54 results on '"Hunter CD"'
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2. Coping attitudes, sources, and practices among Black and Latino college students.
- Author
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Chiang L, Hunter CD, and Yeh CJ
- Abstract
We investigated 130 Black and Latino college students regarding their concerns, attitudes toward professional counseling, sources of support, and coping activities. We found that the Black and Latino cultural emphasis on interdependence influenced attitudes toward using professional resources such as a counselor. We also found a significant two-way interaction between gender and race for attitudes toward professional counseling: Black males had less favorable attitudes in comparison to Black females, while Latino males had more favorable attitudes than did Latino females. Both Black and Latino college students had favorable attitudes toward informal support networks. Differences between Black and Latino college students were found for reported concerns and coping sources. Implications for counseling theory, practice, and research are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2004
3. Citrullinated and malondialdehyde-acetaldehyde-modified fibrinogen activates macrophages and promotes profibrotic responses in human lung fibroblasts.
- Author
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Aripova N, Duryee MJ, Zhou W, England BR, Hunter CD, Klingemann LE, Aripova N, Nelson AJ, Katafiasz D, Bailey KL, Poole JA, Thiele GM, and Mikuls TR
- Subjects
- Humans, Arthritis, Rheumatoid metabolism, Arthritis, Rheumatoid pathology, Extracellular Matrix metabolism, Macrophage Activation drug effects, Transforming Growth Factor beta metabolism, Lung Diseases, Interstitial metabolism, Lung Diseases, Interstitial pathology, Citrulline metabolism, Citrullination, Signal Transduction, Becaplermin metabolism, Acetaldehyde metabolism, Fibrinogen metabolism, Fibroblasts metabolism, Fibroblasts pathology, Lung metabolism, Lung pathology, Macrophages metabolism, Malondialdehyde metabolism
- Abstract
The objective of this study was to assess fibrinogen (FIB) comodified with citrulline (CIT) and/or malondialdehyde-acetaldehyde (MAA) initiates macrophage-fibroblast interactions, leading to extracellular matrix (ECM) deposition that characterizes rheumatoid arthritis-associated interstitial lung disease (RA-ILD). Macrophages (Mϕ) were stimulated with native-FIB, FIB-CIT, FIB-MAA, or FIB-MAA-CIT. Supernatants (SNs) [Mϕ-SN (U-937-derived) or MϕP-SN (PBMC-derived)] or direct antigens were coincubated with human lung fibroblasts (HLFs). Gene expression was examined using RT-PCR. ECM deposition was quantified using immunohistochemistry and Western blot; cell signaling mechanisms were delineated. Platelet-derived growth factor (PDGF)-BB and TGF-β were measured in macrophage supernatants, and inhibition studies were performed using Su16f and SB431542, respectively. HLF gene expression of CD36 , COL6A3 , MMP-9 , MMP-10 , and MMP-12 was increased following stimulations with Mϕ-SN generated from modified FIB but not from direct antigens. HLF stimulated with MϕP-SN
FIB-MAA-CIT derived from patients with RA-ILD resulted in 4- to 30-fold increases in COL6A3 and MMP12 expression; upregulation was greater in HLFs stimulated with MϕP-SN derived from RA-ILD versus controls. HLF exposure to Mϕ-SNFIB-MAA-CIT increased types I/VI collagen deposition versus all other Mϕ-SN groups and was greater than FIB-MAA-CIT stimulation. PDGF-BB and TGF-β signaling had the highest concentrations identified in Mϕ-SNFIB-MAA-CIT and MϕP-SNFIB-MAA-CIT , particularly from RA-ILD-derived cells. PDGF-BB and TGF-β inhibitors, alone and in combination, significantly reduced HLF-mediated ECM deposition from Mϕ-SN stimulations. These results show that comodified fibrinogen activates macrophages to produce PDGF-BB and TGF-β that promotes an aggressive HLF phenotype characterized by increased ECM deposition. These results suggest that targeting CIT and/or MAA modifications or downstream cellular signals could represent novel approaches to RA-ILD treatment. NEW & NOTEWORTHY This report demonstrates that fibrinogen simultaneously harboring two common posttranslational modifications activates macrophages to secrete platelet-derived growth factor (PDGF)-BB and transforming growth factor (TGF)-β. Resulting cross talk between activated macrophages and human lung fibroblasts leads to marked increases in extracellular matrix deposition. These protein modifications are abundant and colocalize in lung tissues from patients with rheumatoid arthritis-associated interstitial lung disease (RA-ILD), and the results suggest that agents targeting citrullination and/or malondialdehyde-acetaldehyde (MAA) adduct formation could represent novel therapeutic strategies.- Published
- 2025
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4. Racial identity and sense of belonging: Moderators of Black college students' institutional race-related stress and anxious arousal.
- Author
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MacNear KA and Hunter CD
- Subjects
- Humans, Male, Female, Universities, Young Adult, Adult, Surveys and Questionnaires, Adolescent, White, Students psychology, Social Identification, Anxiety psychology, Anxiety ethnology, Black or African American psychology, Stress, Psychological ethnology, Stress, Psychological psychology, Racism psychology
- Abstract
Objectives: Race-related stress due to institutional racism is a pervasive reality for Black college students and contributes to poor mental health outcomes such as anxious arousal symptoms. One framework which may account for this association between chronic stress and anxious arousal symptoms is the reserve capacity model. This study investigated whether racial identity dimensions (racial centrality, public regard, private regard) and sense of belonging to the racial group contribute to this population's reserve capacity and buffer the association between institutional race-related stress and anxious arousal symptoms., Method: A sample of 134 Black college students completed racial identity, sense of belonging, and mental health questionnaires. These data were subjected to multiple regression analysis to assess the main and interactive effects of institutional race-related stress and dimensions of interest as predictors of anxious arousal symptoms., Results: The analysis indicated that higher levels of institutional race-related stress, racial centrality, and public regard were each associated with higher levels of anxious arousal while higher levels of private regard and sense of belonging were associated with lower levels of anxious arousal. Further investigation of interaction effects revealed that high levels of sense of belonging and low levels of public regard, respectively, buffered the association between institutional race-related stress and anxious arousal symptoms., Conclusions: These findings illustrate how certain racial identity dimensions and sense of belonging contribute to the reserve capacity of Black students experiencing institutional race-related stress. Results are further discussed in the context of extant literature on Black racial identity and the university context. (PsycInfo Database Record (c) 2025 APA, all rights reserved).
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- 2025
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5. Detection Strategies for Sialic Acid and Sialoglycoconjugates.
- Author
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Hunter CD and Cairo CW
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- Humans, Sialyltransferases metabolism, Neuraminidase metabolism, Sialic Acids metabolism, Sialic Acids chemistry, Sialic Acids analysis, Animals, Substrate Specificity, Glycoconjugates chemistry, Glycoconjugates metabolism, N-Acetylneuraminic Acid metabolism, N-Acetylneuraminic Acid chemistry
- Abstract
Glycoconjugates are a vast class of biomolecules implicated in biological processes important for human health and disease. The structural complexity of glycoconjugates remains a challenge to deciphering their precise biological roles and for their development as biomarkers and therapeutics. Human glycoconjugates on the outside of the cell are modified with sialic (neuraminic) acid residues at their termini. The enzymes that install sialic acids are sialyltransferases (SiaTs), a family of 20 different isoenzymes. The removal and degradation of sialic acids is mediated by neuraminidase (NEU; sialidase) enzymes, of which there are four isoenzymes. In this review, we discuss chemical and biochemical approaches for the detection and analysis of sialoglycoconjugate (SGC) structures and their enzymatic products. The most common methods include affinity probes and synthetic substrates. Fluorogenic and radiolabelled substrates are also important tools for many applications, including screening for enzyme inhibitors. Strategies that give insight into the native substrate-specificity of enzymes that regulate SGCs (SiaT & NEU) are necessary to improve our understanding of the role of sialic acid metabolism in health and disease., (© 2024 The Author(s). ChemBioChem published by Wiley-VCH GmbH.)
- Published
- 2024
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6. Antibodies to Malondialdehyde-Acetaldehyde Adduct Are Associated With Prevalent and Incident Rheumatoid Arthritis-Associated Interstitial Lung Disease in US Veterans.
- Author
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Aripova N, Thiele GM, Duryee MJ, Hunter CD, Yang Y, Roul P, Ascherman DP, Matson SM, Kunkel G, Cannon GW, Wysham KD, Kerr GS, Monach PA, Baker JF, Poole JA, Mikuls TR, and England BR
- Subjects
- Humans, Male, Middle Aged, Female, Aged, United States epidemiology, Prospective Studies, Incidence, Prevalence, Fibrinogen immunology, Immunoglobulin M immunology, Vimentin immunology, Immunoglobulin A immunology, Immunoglobulin A blood, Immunoglobulin G immunology, Immunoglobulin G blood, Collagen immunology, Serum Albumin immunology, Lung Diseases, Interstitial immunology, Lung Diseases, Interstitial epidemiology, Arthritis, Rheumatoid immunology, Arthritis, Rheumatoid epidemiology, Veterans, Acetaldehyde immunology, Autoantibodies immunology, Autoantibodies blood
- Abstract
Objective: The objective of this study is to determine the associations of protein-specific anti-malondialdehyde-acetaldehyde (MAA) antibodies with prevalent and incident rheumatoid arthritis-interstitial lung disease (RA-ILD)., Methods: Within a multicenter, prospective cohort of US veterans with RA, RA-ILD was validated by medical record review of clinical diagnoses, chest imaging, and pathology. Serum antibodies to MAA-albumin, MAA-collagen, MAA-fibrinogen, and MAA-vimentin (IgA, IgM, and IgG) were measured by a standardized enzyme-linked immunosorbent assay. Associations of anti-MAA antibodies with prevalent and incident RA-ILD were assessed using multivariable regression models adjusting for established RA-ILD risk factors., Results: Among 2,739 participants with RA (88% male, mean age of 64 years), there were 114 with prevalent and 136 with incident RA-ILD (average time to diagnosis: 6.6 years). Higher IgM anti-MAA-collagen (per 1 SD: adjusted odds ratio [aOR] 1.28, 95% confidence interval [CI] 1.02-1.61), IgA anti-MAA-fibrinogen (aOR 1.48, 95% CI 1.14-1.92), and IgA (aOR 1.78, 95% CI 1.34-2.37) and IgG (aOR 1.48, 95% CI 1.14-1.92) anti-MAA-vimentin antibodies were associated with prevalent RA-ILD. In incident analyses, higher IgA (per one SD: adjusted hazards ratio [aHR] 1.40, 95% CI 1.11-1.76) and IgM (aHR 1.29, 95% CI 1.04-1.60) anti-MAA-albumin antibody concentrations were associated with increased ILD risk. Participants with IgA (aHR 2.13, 95% CI 1.16-3.90) or IgM (aHR 1.98, 95% CI 1.08-3.64) anti-MAA-albumin antibody concentrations in the highest quartile had an approximately two-fold increased risk of incident RA-ILD. Across all isotypes, anti-MAA-fibrinogen, anti-MAA-collagen, and anti-MAA-vimentin antibodies were not significantly associated with incident RA-ILD., Conclusion: Protein-specific anti-MAA antibodies to collagen, fibrinogen, and vimentin were associated with prevalent RA-ILD. IgA and IgM anti-MAA-albumin antibodies were associated with a higher risk of incident RA-ILD. These findings suggest that MAA modifications and resultant immune responses may contribute to RA-ILD pathogenesis., (© 2024 The Author(s). Arthritis & Rheumatology published by Wiley Periodicals LLC on behalf of American College of Rheumatology. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)
- Published
- 2024
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7. Serum alarmins and the risk of incident interstitial lung disease in rheumatoid arthritis.
- Author
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Poole JA, England BR, Sayles H, Johnson TM, Duryee MJ, Hunter CD, Baker JF, Kerr GS, Kunkel G, Cannon GW, Sauer BC, Wysham KD, Joseph AM, Wallace BI, Thiele GM, and Mikuls TR
- Subjects
- Humans, Female, Male, Middle Aged, Prospective Studies, Incidence, Aged, Interleukin-17 blood, Thymic Stromal Lymphopoietin, Cross-Sectional Studies, Risk Factors, Biomarkers blood, Arthritis, Rheumatoid blood, Arthritis, Rheumatoid complications, Arthritis, Rheumatoid epidemiology, Lung Diseases, Interstitial blood, Lung Diseases, Interstitial epidemiology, Lung Diseases, Interstitial etiology, Interleukin-33 blood, Cytokines blood, Alarmins blood
- Abstract
Objectives: To quantify associations of serum alarmins with risk of rheumatoid arthritis-associated interstitial lung disease (RA-ILD)., Methods: Using serum collected at enrolment, three alarmins (IL-33, thymic stromal lymphopoietin [TSLP] and IL-25) were measured in a multicentre prospective RA cohort. ILD was classified using systematic medical record review. Cross-sectional associations of log-transformed (IL-33, TSLP) or quartile (IL-25) values with RA-ILD at enrolment (prevalent RA-ILD) were examined using logistic regression, while associations with incident RA-ILD developing after enrolment were examined using Cox proportional hazards. Covariates in multivariate models included age, sex, race, smoking status, RA disease activity score and anti-cyclic citrullinated antibody positivity., Results: Of 2835 study participants, 115 participants (4.1%) had prevalent RA-ILD at baseline and an additional 146 (5.1%) developed incident ILD. There were no associations between serum alarmin concentrations and prevalent ILD in unadjusted or adjusted logistic regression models. In contrast, there was a significant inverse association between IL-33 concentration and the risk of developing incident RA-ILD in unadjusted (hazard ratio [HR] 0.73 per log-fold increase; 95% CI: 0.57, 0.95; P = 0.018) and adjusted (HR 0.77; 95% CI: 0.59, 1.00; P = 0.047) models. No significant associations of TSLP or IL-25 with incident ILD were observed., Conclusion: In this study, we observed a significant inverse association between serum IL-33 concentration and the risk of developing incident RA-ILD, but no associations with prevalent ILD. Additional investigation is required to better understand the mechanisms driving this relationship and how serum alarmin IL-33 assessment might contribute to clinical risk stratification in patients with RA., (© The Author(s) 2023. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2024
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8. Combined repetitive inhalant endotoxin and collagen-induced arthritis drive inflammatory lung disease and arthritis severity in a testosterone-dependent manner.
- Author
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Poole JA, Thiele GM, Ramler E, Nelson AJ, Duryee MJ, Schwab AD, Gleason A, Hunter CD, Gaurav R, Wyatt TA, England BR, and Mikuls TR
- Subjects
- Humans, Male, Female, Animals, Mice, Lipopolysaccharides pharmacology, Endotoxins, Testosterone pharmacology, Mice, Inbred DBA, Autoantigens, Arthritis, Experimental, Arthritis, Rheumatoid, Lung Diseases
- Abstract
Respiratory-related diseases are a leading cause of death in rheumatoid arthritis (RA) and are disproportionately higher in men, which may be attributable to environmental risk factors. Animal studies have demonstrated potentiated autoimmunity, arthritis, and profibrotic/inflammatory lung disease with a combination of airborne exposures and collagen-induced arthritis (CIA). This study aimed to determine whether hormone-dependent differences explained these observations. Arthritis-prone male intact and castrated DBA/1J mice received intranasal inhalation of lipopolysaccharide (LPS) daily for 5 wk and CIA induction. Arthritis scores and serum pentraxin-2 levels were increased in castrated versus intact mice. In contrast, airway cell influx, lung tissue infiltrates, and lung levels of proinflammatory and profibrotic markers (C5a, IL-33, and matrix metalloproteinases) were reduced in castrated versus intact mice. CIA + LPS-induced lung histopathology changes and the expression of lung autoantigens including malondialdehyde acetaldehyde (MAA)- and citrulline (CIT)-modified proteins and vimentin were reduced in castrated animals. There were no differences in serum anti-MAA or anti-CIT protein antibody (ACPA) levels or serum pentraxin levels between groups. Testosterone replacement led to a reversal of several lung inflammatory/profibrotic endpoints noted earlier in castrated male CIA + LPS-treated mice with testosterone supplementation promoting neutrophil influx, MAA expression, and TNF-α, IL-6, and MMP-9. These findings imply that testosterone contributes to lung and arthritis inflammatory responses following CIA + LPS coexposure, but not to systemic autoantibody responses. The CIA + LPS model provides a paradigm for investigations focused on the mechanistic underpinnings for epidemiologic and phenotypic sex differences in RA-related lung disease. NEW & NOTEWORTHY Our study shows that testosterone acts as a key immunomodulatory hormone contributing to critical features of rheumatoid arthritis (RA)-associated lung disease in the setting of airborne endotoxin (lipopolysaccharide; LPS) exposures and concomitant arthritis induction in mice. The exaggerated airway inflammation observed following combined exposures in male mice was accompanied by increases in profibrotic mediators, netosis, and increased expression of lung autoantigens, all relevant to the pathogenesis of lung disease in arthritis.
- Published
- 2024
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9. Association between superwoman schema, depression, and resilience: The mediating role of social isolation and gendered racial centrality.
- Author
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Nelson T, Cardemil EV, Overstreet NM, Hunter CD, and Woods-Giscombé CL
- Subjects
- Humans, Female, Depression psychology, Emotions, Social Isolation, Resilience, Psychological, Mental Disorders
- Abstract
Objectives: We examined dimensions of Superwoman Schema as predictors of both depression and resilience. We also investigated if social isolation and gendered racial centrality mediated these relationships., Method: We used path analysis to investigate the direct and indirect effects of an obligation to display an image of strength, emotional suppression, and resistance to vulnerability on depressive symptoms through social isolation. We also explored the direct and indirect effects of an intense motivation to succeed and an obligation to help others on resilience through gendered racial centrality., Results: Emotional suppression and an obligation to help others were directly associated with depression. Emotional suppression, resistance to vulnerability, and an obligation to help others were indirectly associated with depression through social isolation. In contrast, an obligation to display an image of strength and an intense motivation to succeed was associated with resilience and gendered racial centrality., Conclusion: Findings highlight the unique complexity of Superwoman Schema as suggested within qualitative research. Black women's endorsement of Superwoman Schema may be both adaptive in navigating interlocking systems of oppression and psychologically distressing. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
- Published
- 2024
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10. Citrullinated and malondialdehyde-acetaldehyde modified fibrinogen activates macrophages and promotes an aggressive synovial fibroblast phenotype in patients with rheumatoid arthritis.
- Author
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Aripova N, Duryee MJ, England BR, Hunter CD, Mordeson JE, Ryan EM, Daubach EC, Romberger DJ, Thiele GM, and Mikuls TR
- Subjects
- Humans, Fibrinogen, Vimentin, Becaplermin, Collagen Type II, Leukocytes, Mononuclear, Proto-Oncogene Proteins c-akt, Macrophages, Fibroblasts, Acetaldehyde, Hemostatics, Arthritis, Rheumatoid
- Abstract
Objective: Post-translational protein modifications with malondialdehyde-acetaldehyde (MAA) and citrulline (CIT) are implicated in the pathogenesis of rheumatoid arthritis (RA). Although precise mechanisms have not been elucidated, macrophage-fibroblast interactions have been proposed to play a central role in the development and progression of RA. The purpose of our study was to evaluate the downstream effects of macrophage released soluble mediators, following stimulation with fibrinogen (FIB) modified antigens, on human fibroblast-like synoviocytes (HFLS)., Methods: PMA-treated U-937 monocytes (Mϕ) and macrophage-differentiated peripheral blood mononuclear cells (MP) were stimulated with FIB, FIB-MAA, FIB-CIT, or FIB-MAA-CIT. HFLS-RA cells were stimulated directly with FIB antigens or with supernatants (SN) from macrophages (Mϕ-SN or MP-SN) stimulated with FIB antigens. Genes associated with an aggressive HFLS phenotype, extracellular matrix proteins, and activated signaling pathways were evaluated., Results: HFLS-RA cells treated with Mϕ-SN
FIB-CIT and Mϕ-SNFIB-MAA-CIT demonstrated significant increases in mRNA expression of genes associated with an aggressive phenotype at 24-h as compared to direct stimulation with the same antigens. Similar results were obtained using MP-SN. Cellular morphology was altered and protein expression of vimentin (p<0.0001 vs. Mϕ-SNFIB ) and type II collagen (p<0.0001) were significantly increased in HFLS-RA cells treated with any of the Mϕ-SN generated following stimulation with modified antigens. Phosphorylation of JNK, Erk1/2, and Akt were increased most substantially in HFLS-RA treated with Mϕ-SNFIB-MAA-CIT (p<0.05 vs Mϕ-SNFIB ). These and other data suggested the presence of PDGF-BB in Mϕ-SN. Mϕ-SNFIB-MAA-CIT contained the highest concentration of PDGF-BB (p<0.0001 vs. Mϕ-SNFIB ) followed by Mϕ-SNFIB-CIT then Mϕ-SNFIB-MAA . HFLS-RA cells treated with PDGF-BB showed similar cellular morphology to the Mϕ-SN generated following stimulation with modified FIB, as well as the increased expression of vimentin, type II collagen, and the phosphorylation of JNK, Erk1/2 and Akt signaling molecules., Conclusion: Together, these findings support the hypothesis that in response to MAA-modified and/or citrullinated fibrinogen, macrophages release soluble factors including PDGF-BB that induce fibroblast activation and promote an aggressive fibroblast phenotype. These cellular responses were most robust following macrophage activation with dually modified fibrinogen, compared to single modification alone, providing novel insights into the combined role of multiple post-translational protein modifications in the development of RA., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Aripova, Duryee, England, Hunter, Mordeson, Ryan, Daubach, Romberger, Thiele and Mikuls.)- Published
- 2023
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11. The sweet side of sex as a biological variable.
- Author
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Hunter CD, Morris KM, Derksen T, and Willis LM
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- Female, Humans, Male, Reproducibility of Results, Glycosylation, Lectins metabolism, Carbohydrates, Polysaccharides chemistry
- Abstract
Glycobiology as a field holds enormous potential for understanding human health and disease. However, few glycobiology studies adequately address the issue of sex differences in biology, which severely limits the conclusions that can be drawn. Numerous CAZymes, lectins, and other carbohydrate-associated molecules have the potential to be differentially expressed and regulated with sex, leading to differences in O-GlcNAc, N-glycan branching, fucosylation, sialylation, and proteoglycan structure, among others. Expression of proteins involved in glycosylation is influenced through hormones, miRNA, and gene dosage effects. In this review, we discuss the benefits of incorporating sex-based analysis in glycobiology research and the potential drivers of sex differences. We highlight examples of where incorporation of sex-based analysis has led to insights into glycobiology. Finally, we offer suggestions for how to proceed moving forward, even if the experiments are already complete. Properly incorporating sex based analyses into projects will substantially improve the accuracy and reproducibility of studies as well as accelerate the rate of discovery in the glycosciences., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2023
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12. Circulating Adipokines and Associations With Incident Cardiovascular Disease in Rheumatoid Arthritis.
- Author
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Federico LE, Johnson TM, England BR, Wysham KD, George MD, Sauer B, Hamilton BC, Hunter CD, Duryee MJ, Thiele GM, Mikuls TR, and Baker JF
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- Humans, Adiponectin, Coronary Artery Disease, Leptin, Risk Factors, Adipokines blood, Arthritis, Rheumatoid blood, Arthritis, Rheumatoid diagnosis, Arthritis, Rheumatoid epidemiology, Cardiovascular Diseases blood, Cardiovascular Diseases diagnosis, Cardiovascular Diseases epidemiology
- Abstract
Objective: To assess whether circulating levels of adiponectin, leptin, and fibroblast growth factor 21 (FGF-21) are associated with incident cardiovascular disease (CVD) in rheumatoid arthritis (RA)., Methods: Adipokines were measured using banked enrollment serum from patients with RA and dichotomized above/below the median value. Incident CVD events (coronary artery disease [CAD], stroke, heart failure [HF] hospitalization, venous thromboembolism, CVD-related deaths) were identified using administrative data and the National Death Index. Covariates were derived from medical record, biorepository, and registry databases. Multivariable Cox models were generated to quantify associations between adipokine concentrations and CVD incidence. Five-year incidence rates were predicted., Results: Among 2,598 participants, 639 (25%) had at least 1 CVD event over 19,585 patient-years of follow-up. High adiponectin levels were independently associated with HF hospitalization (hazard ratio [HR] 1.39 [95% confidence interval (95% CI) 1.07-1.79], P = 0.01) and CVD-related death (HR 1.49 [95% CI 1.16-1.92], P = 0.002) but not with other CVD events. High leptin was independently associated with CVD-related death (HR 1.44 [95% CI 1.05-1.97], P = 0.02). High FGF-21 levels were independently associated with lower rates of CAD (HR 0.75 [95% CI 0.58-0.97], P = 0.03). In subgroup analyses, associations between high adiponectin and leptin levels with CVD-related death were driven by strong associations in nonobese patients., Conclusion: Adipokines are associated with HF hospitalization and CVD-related death in patients with RA, with stronger associations in nonobese participants. These findings suggest that adipokines effectively predict clinically important outcomes in RA perhaps through an association with body composition and metabolic health. Further study is needed to determine whether adipokine measures might augment existing tools to identify RA patients at increased risk of CVD., (© 2022 American College of Rheumatology. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)
- Published
- 2023
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13. A novel reactive aldehyde species inhibitor prevents the deleterious effects of ethanol in an animal model of alcoholic liver disease.
- Author
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Duryee MJ, Aripova N, Hunter CD, Ruskamp RJ, Tessin MR, Works DR, Mikuls TR, and Thiele GM
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- Mice, Animals, Aldehydes, Disease Models, Animal, Acetaldehyde, Malondialdehyde, Ethanol, Liver Diseases, Alcoholic drug therapy
- Abstract
Background and Aims: Current treatment strategies for alcoholic liver disease (ALD) are limited by the lack of agents specifically targeting the metabolic breakdown products of ethanol. Reactive aldehyde species (RASP) inhibitors have been developed that have the capability to sequester these aldehyde byproducts, potentially limiting toxicity. The purpose of this study was to determine if the RASP inhibitor ADX-629 could target these metabolic breakdown products in a mouse model of ALD., Methods and Results: A chronic/binge mouse model of ALD was used to determine the efficacy of ADX-629 treatment. Mice were fed an alcohol-containing (5 %) liquid or control diet for 10 days and treated by oral gavage with ADX-629 30 min prior to administering a bolus gavage of 31.5 % ethanol. Test groups included: Control - no ADX, Control + ADX, Ethanol - no ADX and Ethanol + ADX. Compared to ethanol-fed mice receiving sham treatment, ethanol mice treated with ADX-629 demonstrated significant decreases (p < 0.05) in liver acetaldehyde (AA), liver malondialdehyde-acetaldehyde (MAA), circulating anti-MAA antibody, liver/serum triglycerides (p < 0.01) levels, and overall fat accumulation in the liver as determined by Oil Red O and bodipy staining (p < 0.0001). Serum levels of pro-inflammatory cytokines IFN-γ and MCP-1 levels were decreased following ADX-629 treatment (p < 0.01)., Conclusions: These findings demonstrate that the use of this unique RASP inhibitor (ADX-629) is effective in the treatment of ALD. Given the ubiquitous nature of aldehydes in the context of tissue inflammation and damage, ADX-629 and other RASP inhibitors may have additional applications in disease states., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)
- Published
- 2022
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14. Elevations in adipocytokines and mortality in rheumatoid arthritis.
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Baker JF, England BR, George MD, Wysham K, Johnson T, Kunkel G, Sauer B, Hamilton BC, Hunter CD, Duryee MJ, Monach P, Kerr G, Reimold A, Xiao R, Thiele GM, and Mikuls TR
- Subjects
- Adult, Humans, Male, Adiponectin, Cytokines, Inflammation, Leptin, Female, Adipokines blood, Arthritis, Rheumatoid mortality
- Abstract
Objectives: This study assessed whether circulating levels of adiponectin and leptin are associated with higher mortality in patients with RA., Methods: Participants were adults from the Veterans Affairs RA Registry. Adipokines and inflammatory cytokines were measured as part of a multi-analyte panel on banked serum at enrolment. Dates and causes of death were derived from the Corporate Data Warehouse and the National Death Index. Covariates were derived from medical record, biorepository and registry databases. Multivariable Cox proportional hazard models evaluated associations between biomarkers and all-cause and cause-specific mortality., Results: A total of 2583 participants were included. Higher adiponectin levels were associated with older age, male sex, white race, lower BMI, autoantibody seropositivity, radiographic damage, longer disease duration, prednisone use and osteoporosis. Higher adiponectin concentrations were also associated with higher levels of inflammatory cytokines but not higher disease activity at enrolment. Leptin was primarily associated with greater BMI and comorbidity. The highest quartile of adiponectin (vs lowest quartile) was associated with higher all-cause mortality [hazard ratio (HR): 1.46 (95% CI: 1.11, 1.93), P = 0.009] and higher cardiovascular mortality [HR: 1.85 (95% CI: 1.24, 2.75), P = 0.003], after accounting for covariates. Higher leptin levels were also associated with greater all-cause and cancer mortality., Conclusions: Elevations in adipokines are associated with age, BMI, comorbidity and severe disease features in RA and independently predict early death. Associations between adiponectin and inflammatory cytokines support the hypothesis that chronic subclinical inflammation promotes metabolic changes that drive elevations in adipokines and yield adverse health outcomes., (Published by Oxford University Press on behalf of the British Society for Rheumatology 2022. This work is written by US Government employees and is in the public domain in the US.)
- Published
- 2022
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15. The costs of anticipating and perseverating about racism: Mechanisms of the associations between racial discrimination, anxious arousal, and low positive affect.
- Author
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Mekawi Y, Heller W, and Hunter CD
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- Female, Humans, Male, Black or African American psychology, Anxiety, Arousal, Black People, Racism psychology
- Abstract
Although numerous studies have documented an association between racial discrimination and internalizing psychopathology symptoms, there is a lack of empirical work that establishes cognitive and emotional mechanisms through which racial discrimination is associated with specific transdiagnostic mental health outcomes (i.e., anxious arousal and low positive affect) among Black Americans., Objective: The goal of this study was to test a new etiological model of how racial discrimination is associated with anxious arousal and low positive affect. The overarching model posits that racial discrimination will be associated with anxious arousal and low positive affect through prolonged activation of race-related stress processes (i.e., anticipatory race-related fear and race-related rumination), the effects of which are conditioned on attention bias to threat., Method: A total of 326 Black participants (72.4% women) completed the study., Results: For anxious arousal, the indirect effect of racial discrimination through anticipatory race-related fear depended on degree of attention bias, with the effect only reaching statistical significance at mean and relatively higher levels of attention bias to threat. For low positive affect, the indirect effect of racial discrimination through race-related rumination only reached a statistical significance at mean and relatively lower levels of attention bias to threat., Conclusions: Racial discrimination is indirectly associated with anxious arousal and low positive affect through the effects of anticipatory race-related fear and race-related rumination, respectively. Implications for etiology and treatment of anxious arousal and low positive affect are discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
- Published
- 2022
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16. Peptidyl arginine deiminase expression and macrophage polarization following stimulation with citrullinated and malondialdehyde-acetaldehyde modified fibrinogen.
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Aripova N, Duryee MJ, Hunter CD, Ryan EM, Daubach EC, Jones SQ, Bierman MM, Ragland AS, Mitra A, England BR, Romberger DJ, Thiele GM, and Mikuls TR
- Subjects
- Acetaldehyde, Citrulline metabolism, Humans, Hydrolases, Macrophages metabolism, Malondialdehyde, Protein-Arginine Deiminases metabolism, RNA, Messenger, Arthritis, Rheumatoid, Fibrinogen metabolism
- Abstract
Objective: Post-translational modifications of extracellular matrix proteins such as fibrinogen may lead to tolerance loss and have been implicated in rheumatoid arthritis (RA) pathogenesis. The purpose of this study was to determine whether fibrinogen (FIB) modified with citrulline (CIT), malondialdehyde-acetaldehyde (MAA) or both leads to altered macrophage polarization, peptidyl arginine deiminase (PAD) expression, or production of citrullinated proteins., Methods: PMA-treated U-937 cells (M0 cells) were stimulated with MAA, CIT or MAA-CIT modified FIB. Macrophage (M1/M2) phenotypes were evaluated by flow cytometry, RT-PCR, and ELISA. PAD enzyme expression and protein citrullination was evaluated using RT-PCR and Western Blot., Results: Flow cytometry revealed that M0 macrophages stimulated with FIB-MAA-CIT resulted in mixed M1/M2 phenotypes as demonstrated by cell surface expression and mRNA levels of CD14, CD192, CD163, and CD206 (p < 0.001 vs. others), and the release of IL-18, IP-10, CCL22, and IL-13 (p < 0.001 vs. others). While FIB-MAA treated M0 cells demonstrated a mixed M1/M2 phenotype, cytokine and cell surface markers differed from FIB-MAA-CIT. Finally, M0 cells treated with FIB-CIT demonstrated markers and cytokines consistent with only the M1-like phenotype. Exposure of M0 cells to FIB-MAA-CIT (at 48 h) and FIB-MAA (at 24 h) led to increased mRNA expression and protein expression of PAD2 (p < 0.001) with increased protein citrullination., Conclusion: These findings suggest that MAA-modification and citrullination of FIB, in isolation or combination, yield specific effects on macrophage polarization, PAD expression and citrullination that ultimately may induce inflammatory and fibrotic responses associated with RA., (Copyright © 2022 Elsevier B.V. All rights reserved.)
- Published
- 2022
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17. Identification of Immunoglobulin G Autoantibody Against Malondialdehyde-Acetaldehyde Adducts as a Novel Serological Biomarker for Ulcerative Colitis.
- Author
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Duryee MJ, Ahmad R, Eichele DD, Hunter CD, Mitra A, Talmon GA, Singh S, Smith LM, Rosen MJ, Dhawan P, Thiele GM, and Singh AB
- Subjects
- Acetaldehyde, Adult, Autoantibodies, Biomarkers, Child, Humans, Immunoglobulin G, Malondialdehyde, Colitis, Ulcerative, Crohn Disease, Inflammatory Bowel Diseases
- Abstract
Introduction: Inflammatory bowel disease (IBD) is associated with immune responses with oxidative stress wherein high levels of malondialdehyde result in the formation of a highly stable and immunogenic malondialdehyde-acetaldehyde adduct (MAA). Thus, this study evaluated the status of MAA and anti-MAA antibody isotypes in IBD and their potential as novel serological biomarkers for differentiating ulcerative colitis (UC) from Crohn's disease (CD)., Methods: Levels of MAA and anti-MAA antibodies were examined in patients with IBD (171), non-IBD gastrointestinal diseases (77), and controls (83) from 2 independent cohorts using immunohistochemistry and enzyme-linked immunosorbent assay. Receiver operating characteristic curves and Youden cutoff index from logistic regression were used to determine the sensitivity and specificity., Results: The MAA and blood immunoglobulin G (IgG) anti-MAA antibody levels were significantly elevated in IBD compared with non-IBD patients (P = 0.0008) or controls (P = 0.02). Interestingly, patients with UC showed higher levels of IgG anti-MAA (P < 0.0001) than patients with CD including those with colonic CD (P = 0.0067). The odds ratio by logistic regression analysis predicted stronger association of IgG anti-MAA antibody with UC than CD. Subsequent analysis showed that IgG anti-MAA antibody levels could accurately identify (P = 0.0004) UC in the adult cohort with a sensitivity of 75.3% and a specificity of 71.4% and an area under the curve of 0.8072 (0.7121-0.9024). The pediatric cohort also showed an area under the curve of 0.8801 (0.7988-0.9614) and precisely distinguished (P < 0.0001) UC with sensitivity (95.8%) and specificity (72.3%)., Discussion: Circulating IgG anti-MAA antibody levels can serve as a novel, noninvasive, and highly sensitive test to identify patients with UC and possibly differentiate them from patients with CD., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of The American College of Gastroenterology.)
- Published
- 2022
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18. The impact of airborne endotoxin exposure on rheumatoid arthritis-related joint damage, autoantigen expression, autoimmunity, and lung disease.
- Author
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Mikuls TR, Gaurav R, Thiele GM, England BR, Wolfe MG, Shaw BP, Bailey KL, Wyatt TA, Nelson AJ, Duryee MJ, Hunter CD, Wang D, Romberger DJ, Ascherman DP, and Poole JA
- Subjects
- Animals, Arthritis, Experimental diagnosis, Arthritis, Experimental immunology, Arthritis, Experimental pathology, Arthritis, Rheumatoid diagnosis, Arthritis, Rheumatoid immunology, Arthritis, Rheumatoid pathology, Autoantibodies immunology, Autoantigens immunology, Case-Control Studies, Dust, Healthy Volunteers, Humans, Inhalation Exposure adverse effects, Interleukin-33 analysis, Interleukin-33 metabolism, Lung immunology, Lung pathology, Lung Diseases, Interstitial pathology, Male, Mice, Severity of Illness Index, Air Pollutants adverse effects, Arthritis, Experimental complications, Arthritis, Rheumatoid complications, Lipopolysaccharides adverse effects, Lung Diseases, Interstitial immunology
- Abstract
Airborne biohazards are risk factors in the development and severity of rheumatoid arthritis (RA) and RA-associated lung disease, yet the mechanisms explaining this relationship remain unclear. Lipopolysaccharide (LPS, endotoxin) is a ubiquitous inflammatory agent in numerous environmental and occupational air pollutant settings recognized to induce airway inflammation. Combining repetitive LPS inhalation exposures with the collagen induced arthritis (CIA) model, DBA1/J mice were assigned to either: sham (saline injection/saline inhalation), CIA (CIA/saline), LPS (saline/LPS 100 ng inhalation), or CIA + LPS for 5 weeks. Serum anti-citrullinated (CIT) protein antibody (ACPA) and anti-malondialdehyde-acetaldehyde (MAA) antibodies were strikingly potentiated with co-exposure (CIA + LPS). CIT- and MAA-modified lung proteins were increased with co-exposure and co-localized across treatment groups. Inhaled LPS exacerbated arthritis with CIA + LPS > LPS > CIA versus sham. Periarticular bone loss was demonstrated in CIA and CIA + LPS but not in LPS alone. LPS induced airway inflammation and neutrophil infiltrates were reduced with co-exposure (CIA + LPS). Potentially signaling transition to pro-fibrotic processes, there were increased infiltrates of activated CD11c
+ CD11b+ macrophages and transitioning CD11c+ CD11bint monocyte-macrophage populations with CIA + LPS. Moreover, several lung remodeling proteins including fibronectin and matrix metalloproteinases as well as complement C5a were potentiated with CIA + LPS compared to other treatment groups. IL-33 concentrations in lung homogenates were enhanced with CIA + LPS with IL-33 lung staining driven by LPS. IL-33 expression was also significantly increased in lung tissues from patients with RA-associated lung disease (N = 8) versus controls (N = 7). These findings suggest that patients with RA may be more susceptible to developing interstitial lung disease following airborne biohazard exposures enriched in LPS., (Copyright © 2021 Elsevier B.V. All rights reserved.)- Published
- 2021
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19. Performance of a commercially available multiplex platform in the assessment of circulating cytokines and chemokines in patients with rheumatoid arthritis and osteoarthritis.
- Author
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Maloley PM, England BR, Sayles HR, Thiele GM, Duryee MJ, Hunter CD, Payne JB, and Mikuls TR
- Subjects
- Aged, Arthritis, Rheumatoid diagnosis, Biomarkers blood, Female, Humans, Male, Middle Aged, Osteoarthritis diagnosis, Predictive Value of Tests, Reproducibility of Results, Rheumatoid Factor blood, United States, Arthritis, Rheumatoid blood, Chemokines blood, Cytokines blood, Immunoassay, Osteoarthritis blood
- Abstract
Background/objective: Cytokines and chemokines (cytokines) are central to rheumatoid arthritis (RA) pathogenesis, with increasing use of multiplex immunoassays in clinical/research settings. Rheumatoid factor (RF) may interfere with assay outcomes by nonspecifically binding detection analytes. We evaluated the performance of a commercially available multiplex platform, including assessment of the impact of RF depletion., Methods: Forty-five cytokines were tested using Meso Scale Discovery V-PLEX™ and samples from 40 RA and 40 osteoarthritis (OA) patients. Select samples were depleted of RF using a commercial binder. Performance was assessed using intra-assay coefficients of variation (CV), intraclass correlation coefficients (ICC), percent change following RF depletion, and disease discrimination. Values above or below quantification thresholds were imputed., Results: Of the 45 cytokines analyzed, 31 yielded CVs <10%; none demonstrated CVs >30%. ICCs universally exceeded 0.85 with the exception of eight analytes. RF depletion altered cytokine values by <15% for 40 analytes with larger changes (>30%) only seen for one analyte. Twenty-three cytokines differed significantly based on measurement in plasma vs. serum. Three analytes were higher in the serum of RA vs. OA (IL-10, IP-10, TNFα), and none were significantly greater in OA vs. RA. Seventeen analytes required imputation for >50% of the samples tested, primarily related to concentrations below the lower limit of quantification threshold., Conclusion: The results from this commercially available multiplex assay were generally highly reproducible and interference induced by RF only meaningfully impacted the quantification of five of the analytes examined., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
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20. Associations between an expanded autoantibody profile and treatment responses to biologic therapies in patients with rheumatoid arthritis.
- Author
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Petro AD, Dougherty J, England BR, Sayles H, Duryee MJ, Hunter CD, Kremer JM, Pappas DA, Robinson WH, Curtis JR, Thiele GM, and Mikuls TR
- Subjects
- Acetaldehyde immunology, Adult, Aged, Anti-Citrullinated Protein Antibodies blood, Antirheumatic Agents adverse effects, Arthritis, Rheumatoid blood, Arthritis, Rheumatoid diagnosis, Arthritis, Rheumatoid immunology, Biological Products adverse effects, Biomarkers blood, Comparative Effectiveness Research, Drug Substitution, Female, Humans, Male, Malondialdehyde immunology, Middle Aged, Prospective Studies, Registries, Remission Induction, Rheumatoid Factor blood, Treatment Outcome, Tumor Necrosis Factor Inhibitors adverse effects, Antirheumatic Agents therapeutic use, Arthritis, Rheumatoid drug therapy, Autoantibodies blood, Biological Products therapeutic use, Tumor Necrosis Factor Inhibitors therapeutic use
- Abstract
Background: Although biologics represent a major advance in rheumatoid arthritis (RA), many patients fail to achieve adequate responses to these agents. We examined whether combined positivity to three well-characterized autoantibodies predicts treatment response among RA patients initiating biologics., Methods: The study included biologic-naïve patients initiating anti-TNF treatment, biologic-exposed patients switching to rituximab or tocilizumab, and patients (biologic naïve or exposed) initiating abatacept. Rheumatoid factor (RF), anti-cyclic citrullinated peptide (CCP) antibody, and IgG antibodies to malondialdehyde-acetaldehyde (MAA) were measured using banked enrollment serum. The relationship between the number of autoantibodies positive (0-3) and treatment response (absolute improvement in 28-joint Disease Activity Score [DAS28-CRP] or improvement > 1.2) at 6 months was examined using multivariable linear and logistic regression., Results: Of 1,229 patients initiating biologics, 79% were women; 89% were Caucasian. The number of baseline RA-related autoantibodies positive was associated with improved treatment response in a dose-dependent fashion. Compared to patients seronegative for all autoantibodies, adjusting for covariates, those positive for all three were more than twice (OR 2.35; 95% CI 1.57-3.51) as likely to achieve DAS28 improvement > 1.2 units. Associations of autoantibody positivity with biologic treatment response were strongest for anti-CCP antibody, persisted in analyses limited to biologic naïve patients, and did not appear to differ markedly among different agents examined., Conclusion: An expanded autoantibody profile appears to significantly predict RA treatment response to biologic treatment in a dose-dependent fashion. Incorporating these serologic profiles with additional biomarkers or other informative patient characteristics could provide an opportunity to personalize RA management., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2021
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21. Autoantibodies to Malondialdehyde-Acetaldehyde Are Detected Prior to Rheumatoid Arthritis Diagnosis and After Other Disease Specific Autoantibodies.
- Author
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Mikuls TR, Edison J, Meeshaw E, Sayles H, England BR, Duryee MJ, Hunter CD, Kelmenson LB, Kay Moss L, Feser ML, Wagner B, Parish MC, Deane KD, and Thiele GM
- Subjects
- Adult, Anti-Citrullinated Protein Antibodies blood, Arthritis, Rheumatoid blood, Arthritis, Rheumatoid immunology, Case-Control Studies, Female, Humans, Immunoglobulin M immunology, Male, Middle Aged, Rheumatoid Factor blood, Acetaldehyde immunology, Arthritis, Rheumatoid diagnosis, Autoantibodies blood, Malondialdehyde immunology
- Abstract
Objective: To examine serum autoantibodies to malondialdehyde-acetaldehyde (MAA) prior to rheumatoid arthritis (RA) diagnosis., Methods: Concentrations of anti-MAA antibody isotypes, anti-cyclic citrullinated peptide 2 (anti-CCP-2), and IgM rheumatoid factor (IgM-RF) were evaluated before and after RA diagnosis in samples from cases (n = 214) and controls (n = 210). The timing of elevations in autoantibody concentrations relative to RA diagnosis was explored using separate mixed models for each antibody and/or isotype. Associations between prediagnosis autoantibody concentrations in RA patients were examined using mixed effects linear regression models., Results: Concentrations of IgG (log
2 difference 0.34) and IgA (log2 difference 0.43) anti-MAA antibodies in RA patients diverged from controls at 3.0 years and 2.3 years prior to diagnosis, respectively (P < 0.05 for both). There was no evidence of case-control divergence for IgM anti-MAA antibody concentration. Anti-CCP-2 and IgM-RF concentrations diverged between RA patients and controls beginning at 17.6 years and 7.2 years prior to RA diagnosis, respectively. All 3 anti-MAA antibody isotypes (IgA, IgM, and IgG) were significantly associated with anti-CCP-2 antibody and RF concentrations prior to diagnosis (β = 0.22-0.27 for IgM-RF; β = 0.44-0.93 for anti-CCP-2) (P < 0.001)., Conclusion: IgG and IgA anti-MAA autoantibodies are elevated prior to RA diagnosis but appear later in the preclinical course than anti-CCP-2 or RF. These findings suggest that MAA formation and anti-MAA immune responses could play a role in the transition from subclinical autoimmunity to clinically apparent arthritis., (© 2020, American College of Rheumatology.)- Published
- 2020
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22. Human neuraminidases have reduced activity towards modified sialic acids on glycoproteins.
- Author
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Hunter CD, Porter EM, and Cairo CW
- Subjects
- Acetylation, Animals, Cattle, Humans, Neuraminidase chemistry, Substrate Specificity, Mucins chemistry, Mucins metabolism, Neuraminidase metabolism, Sialic Acids metabolism
- Abstract
Multiple levels of diversity in sialic acid presentation can influence the substrate activity of sialosides for glycoside hydrolases. Few reports have investigated the specificity of human neuraminidase (hNEU) activity towards modified sialic acid residues that can occur on glycoproteins. Previously, we evaluated hNEU activity towards 9-O-acetylated sialic acid in glycolipid substrates and found that hNEU generally discriminated against 9-O-acetylated sialic acid over Neu5Ac. Here, we have investigated the substrate specificity of hNEU enzymes for a glycoprotein substrate (bovine submaxillary mucin) containing 9-O-acetylated and Neu5Gc residues. Using this model substrate, we observe a general trend for hNEU tolerance of Neu5Ac > Neu5Gc ≫ Neu5,9Ac
2 , consistent with our previous results with glycolipid substrates. These results expand our understanding of hNEU enzyme specificity and suggest that naturally occurring modifications of sialic acids can play a role in regulating hNEU activity., (Copyright © 2020 Elsevier Ltd. All rights reserved.)- Published
- 2020
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23. From maternal tending to adolescent befriending: The adolescent transition of social support.
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Rodrigues MA, Sanford SR, Rogers MP, Lee KMN, Wilson MA, Amos J, Hunter CD, and Clancy KBH
- Subjects
- Adolescent, Female, Humans, Interpersonal Relations, Object Attachment, Psychology, Adolescent, Depression epidemiology, Friends psychology, Parent-Child Relations, Social Support
- Abstract
Attachment theory holds that parental relationships have lifelong effects on offspring social lives. The tend-and-befriend hypothesis posits that female friendships among humans evolved as part of a primate-wide coping mechanism to mediate stress by relying on social support. Here we bridge developmental and evolutionary frameworks to examine adolescent girls' perception of their reliance on female friendship for social support, how perceptions of parental relationships affect peer relationships, and the extent to which parent and peer relationships buffer depressive symptoms. We predict perceived maternal relationship quality will be positively associated with close female friendships, and maternal relationships, paternal relationships, and female friendship will buffer depressive symptoms. Participants were adolescent girls from a summer science camp (N = 95). Participants filled out demographic information, social network surveys, the Parent-Adolescent Communication Scale, and the Center for Epidemiology Depression Scale. Data was analyzed with Pearson's correlations, t tests, and path analysis. Adolescent girls with few female friends, compared with girls who had more than two very close female friends, experienced more depressive symptoms (t = 3.382, p = .001, D = 0.784). Adolescent girls with few female friends experienced more depressive symptoms compared to girls with two or more very close female friends (t = 3.382, p = .001, D = 0.784). Stronger maternal and paternal relationships were associated with having more female friends (maternal: t = -3.213, p = .003, D = 0.837; paternal: t = -2.432; p = .017). In the path analysis model, only maternal relationship quality significantly predicted female friendship category (β = .33, CR = 2.770, p < .006). Furthermore, participants with two or more very close female friends and higher paternal relationship quality had significantly fewer depressive symptoms (friends; β = -.19, CR = -2.112, p = .035; paternal: β = -.33, CR = -3.220, p < .001), and older participants had more depressive symptoms (β = .17, CR = -1.931, p = .036). These results provide additional support for the tend-and-befriend hypothesis, suggesting that maternal tending sets the stage for close female friendships., (© 2019 Wiley Periodicals, Inc.)
- Published
- 2020
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24. Immunogenic and inflammatory responses to citrullinated proteins are enhanced following modification with malondialdehyde-acetaldehyde adducts.
- Author
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Thiele GM, Duryee MJ, Hunter CD, England BR, Fletcher BS, Daubach EC, Pospisil TP, Klassen LW, and Mikuls TR
- Subjects
- Acetaldehyde chemistry, Adjuvants, Immunologic chemistry, Animals, Anti-Citrullinated Protein Antibodies immunology, Arthritis, Rheumatoid immunology, CHO Cells, Cricetulus, Cytokines metabolism, Humans, Immunogenicity, Vaccine, Inflammation metabolism, Male, Malondialdehyde chemistry, Mice, Inbred DBA, Monocytes metabolism, Receptors, Scavenger metabolism, Serum Albumin, Human chemistry, Serum Albumin, Human immunology, T-Lymphocytes immunology, T-Lymphocytes metabolism, THP-1 Cells, Acetaldehyde immunology, Anti-Citrullinated Protein Antibodies blood, Citrullination immunology, Malondialdehyde immunology
- Abstract
Background/objective: Malondialdehyde-acetaldehyde adducts (MAA) act as potent immune adjuvants and co-localize with citrullinated antigens in tissues effected by rheumatoid arthritis (RA). We sought to examine the role of MAA-adducts in promoting RA-related autoimmunity and inflammation., Methods: DBA/J1 mice were immunized with human serum albumin (HSA), HSA-MAA, citrullinated HSA (HSA-Cit), or HSA-MAA-Cit with subsequent measurement of serum anti-citrullinated protein antibody (ACPA) and anti-Cit T cell responses. Cellular binding of the same antigens was examined using THP-1 monocytes and Chinese Hamster Ovary (CHO) cells transfected with specific scavenger receptors (SRs: TLR4, SR-B2, SREC-1). The effects of these antigens on THP-1 activation were then examined by quantifying plate adherence, pro-inflammatory (TNFα, IL-1β, IL-10) cytokine release, and SR (CD14, SR-B2)/co-stimulatory molecule (CD80, HLA-DR) expression. Comparisons were completed using one-way ANOVA with Tukey's post-hoc test., Results: Mice immunized with co-modified HSA produced significantly higher ACPA concentrations than all other groups whereas T cell responses to citrullinated proteins were highest following immunization with HSA-MAA. Both transfected CHO and THP-1 cells demonstrated significantly higher binding of HSA-MAA-Cit vs. HSA or HSA-Cit. THP-1 cells exposed to HSA-MAA-Cit expressed significantly higher concentrations of TNFα, IL-1β, and IL-10 vs. all other groups. Furthermore, THP-1 cells demonstrated significantly increased plate adherence and higher expression of CD14, SR-B2, and HLA-DR following incubation with HSA-MAA-Cit vs. HSA or HSA-Cit., Conclusion: These studies demonstrate that MAA-adduction of citrullinated antigen greatly enhances immune and cellular responses, potentially acting as a key co-factor in RA pathogenesis., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2020
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25. Surface nano-modification by ion beam-assisted deposition alters the expression of osteogenic genes in osteoblasts.
- Author
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Miralami R, Haider H, Sharp JG, Namavar F, Hartman CW, Garvin KL, Hunter CD, Premaraj T, and Thiele GM
- Subjects
- Apoptosis drug effects, Cell Adhesion drug effects, Cell Differentiation drug effects, Cell Line, Tumor, Cell Proliferation drug effects, Glass chemistry, Humans, Osteoblasts cytology, Osteogenesis drug effects, Surface Properties, Titanium chemistry, Coated Materials, Biocompatible chemistry, Coated Materials, Biocompatible pharmacology, Gene Expression Regulation drug effects, Nanostructures chemistry, Osteoblasts drug effects, Osteoblasts metabolism, Osteogenesis genetics
- Abstract
Biomaterials with enhanced biocompatibility are favored in implant studies to improve the outcomes of total joint replacement surgeries. This study tested the hypothesis that nano-structured surfaces for orthopedic applications, produced by the ion beam-assisted deposition method, would enhance osteointegration by altering the expression of bone-associated genes in osteoblasts. The ion beam-assisted deposition technique was employed to deposit nano-films on glass or titanium substrates. The effects of the ion beam-assisted deposition produced surfaces on the human osteosarcoma cell line SAOS-2 at the molecular level were investigated by assays of adhesion, proliferation, differentiation, and apoptosis on coated surfaces versus uncoated cobalt-chrome, as the control. Ion beam-assisted deposition nano-coatings enhanced bone-associated gene expression at initial cell adhesion, proliferation, and differentiation compared to cobalt-chrome surfaces as assessed by polymerase chain reaction techniques. Increased cell proliferation was observed using a nuclear cell proliferation-associated antigen. Moreover, enhanced cell differentiation was determined by alkaline phosphatase activity, an indicator of bone formation. In addition, programmed cell death assessed by annexin V staining and flow cytometry was lower on nano-surfaces compared to cobalt-chrome surfaces. Overall, the results indicate that nano-coated surfaces produced by the ion beam-assisted deposition technique for use on implants were superior to orthopedic grade cobalt-chrome in supporting bone cell adhesion, proliferation, and differentiation and reducing apoptosis. Thus, surface properties altered by the ion beam-assisted deposition technique should enhance bone formation and increase the biocompatibility of bone cell-associated surfaces.
- Published
- 2019
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26. A quantitative, high-throughput method identifies protein-glycan interactions via mass spectrometry.
- Author
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Kitov PI, Kitova EN, Han L, Li Z, Jung J, Rodrigues E, Hunter CD, Cairo CW, Macauley MS, and Klassen JS
- Subjects
- Ligands, Protein Binding, Substrate Specificity, High-Throughput Screening Assays methods, Polysaccharides metabolism, Proteins metabolism, Spectrometry, Mass, Electrospray Ionization methods
- Abstract
Glycan binding by glycan-binding proteins and processing by carbohydrate-active enzymes is implicated in physiological and pathophysiological processes. Comprehensive mapping of glycan interactions is essential to understanding of glycan-mediated biology and can guide the development of new diagnostics and therapeutics. Here, we introduce the competitive universal proxy receptor assay (CUPRA), which combines electrospray ionization mass spectrometry, competitive binding and heterobifunctional glycan-based ligands to give a quantitative high-throughput method for screening glycan libraries against glycan-binding and glycan-processing proteins. Application of the assay to human (siglec-2), plant ( Sambucus nigra and Maackia amurensis lectins) and bacterial (cholera toxin, and family 51 carbohydrate binding module) proteins allowed for the identification of ligands with affinities ( K
d ) ≤ 1 mM. The assay is unprecedentedly versatile and can be applied to natural libraries and, when implemented in a time-resolved manner, provides a quantitative measure of the activities and substrate specificity of carbohydrate-active enzymes., Competing Interests: Competing interestsThe authors declare no competing interests.- Published
- 2019
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27. Antioxidant properties of citric acid interfere with the uricase-based measurement of circulating uric acid.
- Author
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Ryan EM, Duryee MJ, Hollins A, Dover SK, Pirruccello S, Sayles H, Real KD, Hunter CD, Thiele GM, and Mikuls TR
- Subjects
- Aged, Anticoagulants chemistry, Biomarkers blood, Cohort Studies, Glucose analogs & derivatives, Glucose chemistry, Gout blood, Gout diagnosis, Healthy Volunteers, Humans, Male, Middle Aged, Sodium Citrate chemistry, Antioxidants chemistry, Blood Specimen Collection methods, Citric Acid chemistry, Urate Oxidase chemistry, Uric Acid blood
- Abstract
Background: Circulating uric acid (UA) is an important biomarker, not only in the detection and management of gout, but also in assessing the risk of related comorbidity. The impact of collection methods on clinical UA measurements has been the subject of limited study. After observing significant differences between UA concentrations of blood samples obtained by different collection tubes, we began examining the effects of exogenous tube components on measured UA concentrations. We aimed to: (1) demonstrate the variability in uricase-based UA measurements attributable to different collection methods and (2) identify factors influencing this variability., Methods: Blood samples from human subjects were collected using Serum Separator Tubes (SST tubes), Acid Citrate Dextrose (ACD) tubes, and Sodium Citrate (SC) tubes. Circulating UA concentrations were measured by chemistry analyzers utilizing the uricase method. Absorbance assays were run in order to determine the effects of citric acid, sodium citrate, and dextrose on measured absorbance in the presence of leuco crystal violet dye, hydrogen peroxide, and peroxidase. Statistical analyses-including Student's T tests and ANOVA-were used to compare results., Results: UA concentrations of blood samples collected in ACD tubes were significantly lower than those collected in SST tubes (P < 0.01). Samples collected in SC tubes trended towards lower UA measurements than samples collected in SST tubes, although this difference did not reach statistical significance (P = 0.06). Blood samples spiked with separate concentrations of sodium citrate (3.2 and 22.0 g/L), citric acid (8.0 g/L), and dextrose (24.5 g/L) demonstrated significantly lower UA measurements compared to controls (P < 0.01). Absorbance assays demonstrated that increasing concentrations of citric acid and sodium citrate-in the presence of leuco crystal violet, hydrogen peroxide, and peroxidase-decreased the amount of oxidized dye in the uricase method of UA measurement in a dose-dependent manner (P < 0.01). In contrast, dextrose did not significantly alter the amount of oxidized dye available., Discussion: Our results indicate that citric acid obstructs accurate uricase-based UA measurement, providing falsely low values. Citric acid, a known antioxidant, scavenges hydrogen peroxide, a key intermediate using the uricase method. By scavenging hydrogen peroxide, citric acid decreases the amount of oxidized leuco dye leading to falsely low UA measurements. Therefore, collection tubes, like ACD and SC tubes, which contain concentrations of citric acid or its conjugate base sodium citrate should not be used to measure circulating UA levels when utilizing uricase-based measurement methods., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2019
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28. Novel Antioxidant Properties of Doxycycline.
- Author
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Clemens DL, Duryee MJ, Sarmiento C, Chiou A, McGowan JD, Hunter CD, Schlichte SL, Tian J, Klassen LW, O'Dell JR, Thiele GM, Mikuls TR, Zimmerman MC, and Anderson DR
- Subjects
- Cell-Free System, Doxycycline pharmacology, Free Radical Scavengers pharmacology, HEK293 Cells, Humans, Hydrogen Peroxide chemistry, Hydrogen Peroxide metabolism, Inflammation drug therapy, Inflammation metabolism, Malondialdehyde chemistry, Malondialdehyde metabolism, NF-E2-Related Factor 2 metabolism, Oxidative Stress drug effects, Superoxides chemistry, Superoxides metabolism, Doxycycline chemistry, Free Radical Scavengers chemistry
- Abstract
Doxycycline (DOX), a derivative of tetracycline, is a broad-spectrum antibiotic that exhibits a number of therapeutic activities in addition to its antibacterial properties. For example, DOX has been used in the management of a number of diseases characterized by chronic inflammation. One potential mechanism by which DOX inhibits the progression of these diseases is by reducing oxidative stress, thereby inhibiting subsequent lipid peroxidation and inflammatory responses. Herein, we tested the hypothesis that DOX directly scavenges reactive oxygen species (ROS) and inhibits the formation of redox-mediated malondialdehyde-acetaldehyde (MAA) protein adducts. Using a cell-free system, we demonstrated that DOX scavenged reactive oxygen species (ROS) produced during the formation of MAA-adducts and inhibits the formation of MAA-protein adducts. To determine whether DOX scavenges specific ROS, we examined the ability of DOX to directly scavenge superoxide and hydrogen peroxide. Using electron paramagnetic resonance (EPR) spectroscopy, we found that DOX directly scavenged superoxide, but not hydrogen peroxide. Additionally, we found that DOX inhibits MAA-induced activation of Nrf2, a redox-sensitive transcription factor. Together, these findings demonstrate the under-recognized direct antioxidant property of DOX that may help to explain its therapeutic potential in the treatment of conditions characterized by chronic inflammation and increased oxidative stress.
- Published
- 2018
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29. Molecular dynamics simulations of viral neuraminidase inhibitors with the human neuraminidase enzymes: Insights into isoenzyme selectivity.
- Author
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Richards MR, Guo T, Hunter CD, and Cairo CW
- Subjects
- Amino Acid Sequence, Antiviral Agents chemistry, Antiviral Agents metabolism, Binding Sites, Catalytic Domain, Enzyme Inhibitors metabolism, Humans, Inhibitory Concentration 50, Isoenzymes antagonists & inhibitors, Isoenzymes metabolism, Kinetics, Molecular Dynamics Simulation, Neuraminidase metabolism, Sequence Alignment, Viral Proteins metabolism, Zanamivir chemistry, Zanamivir metabolism, Enzyme Inhibitors chemistry, Neuraminidase antagonists & inhibitors, Viral Proteins antagonists & inhibitors
- Abstract
Inhibitors of viral neuraminidase enzymes have been previously developed as therapeutics. Humans can express multiple forms of neuraminidase enzymes (NEU1, NEU2, NEU3, NEU4) that share a similar active site and enzymatic mechanism with their viral counterparts. Using a panel of purified human neuraminidase enzymes, we tested the inhibitory activity of 2-deoxy-2,3-dehydro-N-acetylneuraminic acid (DANA), zanamivir, oseltamivir, and peramivir against each of the human isoenzymes. We find that, with the exceptions of DANA and zanamivir, these compounds show generally poor activity against the human neuraminidase enzymes. To provide insight into the interactions of viral inhibitors with human neuraminidases, we conducted molecular dynamics simulations using homology models based on coordinates reported for NEU2. Simulations revealed that an organized water is displaced by zanamivir in binding to NEU2 and NEU3 and confirmed the critical importance of engaging the binding pocket of the C7-C9 glycerol sidechain. Our results suggest that compounds designed to target the human neuraminidases should provide more selective tools for interrogating these enzymes. Furthermore, they emphasize a need for additional structural data to enable structure-based drug design in these systems., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
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30. Synthetic Strategies for Modified Glycosphingolipids and Their Design as Probes.
- Author
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Hunter CD, Guo T, Daskhan G, Richards MR, and Cairo CW
- Subjects
- Carbohydrate Conformation, Glycoside Hydrolases chemistry, Glycosphingolipids chemistry, Glycosylation, Glycosyltransferases chemistry, Molecular Probes chemistry, Chemistry Techniques, Synthetic methods, Glycosphingolipids chemical synthesis, Molecular Probes chemical synthesis
- Abstract
The plasma membrane of cells contains a diverse array of lipids that provide important structural and biological features. Glycolipids are typically a minor component of the cell membrane and consist primarily of glycosphingolipids (GSLs). GSLs in vertebrates contain a multifarious assortment of glycan headgroups, which can be important to biological functions based on lipid-lipid and lipid-protein interactions. The design of probes to study these complex targets requires advanced synthetic methodologies. In this Review, we will discuss recent advances in chemical and chemoenzymatic synthesis of GSLs in conjunction with the use of these approaches to design new probes. Examples using either chemical or enzymatic semisynthesis methods starting from isolated GSLs will also be reviewed. Focusing primarily on vertebrate glycolipids, we will highlight examples of radionuclide, fluorophore, photoresponsive, and bioorthogonal tagged GSL probes.
- Published
- 2018
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31. N-Acetyl Cysteine Treatment Restores Early Phase Fracture Healing in Ethanol-Fed Rats.
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Duryee MJ, Dusad A, Hunter CD, Kharbanda KK, Bruenjes JD, Easterling KC, Siebler JC, Thiele GM, and Chakkalakal DA
- Subjects
- Animals, Dose-Response Relationship, Drug, Ethanol administration & dosage, Femur metabolism, Fracture Healing physiology, Inflammation Mediators antagonists & inhibitors, Inflammation Mediators metabolism, Male, Rats, Rats, Wistar, Treatment Outcome, Acetylcysteine pharmacology, Ethanol toxicity, Femur drug effects, Femur injuries, Fracture Healing drug effects
- Abstract
Background: Fracture healing in alcoholics is delayed and often associated with infections resulting in prolonged rehabilitation. It has been reported that binge drinking of alcohol increases oxidative stress and delays fracture healing in rats, which is prevented by treatment with the antioxidant n-acetyl cysteine (NAC). Oxidative stress is a significant factor in pathologies of various organs resulting from chronic alcoholism. Therefore, we hypothesize that treatment with NAC reduces oxidative stress and restores fracture healing in chronic alcoholics., Methods: Rats (10 months old) were pair-fed the Lieber-DeCarli ethanol (EtOH) diet or control diet for 16 weeks. A closed fracture was performed and rats allowed to recover for 72 hours. Rats were divided into 4 groups-control, control + NAC, EtOH, and EtOH + NAC-and injected intraperitoneally with 200 mg/kg of NAC daily for 3 days. Serum and bone fracture callus homogenates were collected and assayed for traditional markers of inflammation, oxidative stress, and bone regeneration., Results: The oxidative stress marker malondialdehyde (MDA) was increased in both serum and bone tissue in EtOH-fed animals compared to controls. NAC treatment significantly (p < 0.01) reduced MDA to near normal levels and dramatically increased the index of antioxidant efficacy (catalase/MDA ratio) (p < 0.01). Inflammatory markers tumor necrosis factor-α, interferon-γ, and interleukin-6 were significantly decreased in serum and callus following NAC treatment. NAC treatment reduced EtOH-induced bone resorption as evidenced by significant decreases in C-telopeptide of type-I-collagen levels (p < 0.05) and band-5 tartrate-resistant acid phosphatase levels in the tissue (p < 0.001)., Conclusions: Oxidative stress and excessive inflammation are involved in the inhibition of fracture healing by EtOH. In this study, early short-term treatment of EtOH-fed animals with the antioxidant NAC reduced oxidative stress and normalized the innate immune response to fracture in the early phase of fracture healing, thereby restoring the normal onset of bone regeneration., (Copyright © 2018 by the Research Society on Alcoholism.)
- Published
- 2018
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32. Human Neuraminidase Isoenzymes Show Variable Activities for 9- O-Acetyl-sialoside Substrates.
- Author
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Hunter CD, Khanna N, Richards MR, Rezaei Darestani R, Zou C, Klassen JS, and Cairo CW
- Subjects
- Acetylation, Humans, Neuraminidase metabolism, Spectrometry, Fluorescence, Spectrometry, Mass, Electrospray Ionization, Substrate Specificity, Isoenzymes metabolism, Neuraminidase chemistry, Sialic Acids metabolism
- Abstract
Recognition of terminal sialic acids is central to many cellular processes, and structural modification of sialic acid can disrupt these interactions. A prominent, naturally occurring, modification of sialic acid is 9- O-acetylation (9- O-Ac). Study of this modification through generation and analysis of 9- O-Ac sialosides is challenging because of the lability of the acetate group. Fundamental questions regarding the role of 9- O-Ac sialic acids remain unanswered, including what effect it may have on recognition and hydrolysis by the human neuraminidase enzymes (hNEU). To investigate the substrate activity of 9- O-acetylated sialic acids (Neu5,9Ac
2 ), we synthesized an acetylated fluorogenic hNEU substrate 2'-(4-methylumbelliferyl)-9- O-acetyl-α-d- N-acetylneuraminic acid. Additionally, we generated a panel of octyl sialyllactosides containing modified sialic acids including variation in linkage, 9- O-acetylation, and C-5 group (Neu5Gc). Relative rates of substrate cleavage by hNEU were determined using fluorescence spectroscopy and electrospray ionization mass spectrometry. We report that 9- O-acetylation had a significant, and differential, impact on sialic acid hydrolysis by hNEU with general substrate tolerance following the trend of Neu5Ac > Neu5Gc ≫ Neu5,9Ac2 for NEU2, NEU3, and NEU4. Both NEU2 and NEU3 had remarkably reduced activity for Neu5,9Ac2 containing substrates. Other isoenzymes appeared to be more tolerant, with NEU4 even showing increased activity on Neu5,9Ac2 substrates with an aryl aglycone. The impact of these minor structural changes to sialic acid on hNEU activity was unexpected, and these results provide evidence of the substantial influence of 9- O-Ac modifications on hNEU enzyme substrate specificity. Furthermore, these findings may implicate hNEU in processes governed by 9- O-acetyltransferases and -esterases.- Published
- 2018
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33. Liver tissue metabolically transformed by alcohol induces immune recognition of liver self-proteins but not in vivo inflammation.
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Duryee MJ, Wiese BM, Bowman JR, Vanlandingham JD, Klassen LW, Thiele GE, Hunter CD, Anderson DR, Mikuls TR, and Thiele GM
- Subjects
- Acetaldehyde metabolism, Adoptive Transfer, Animals, Cell Movement, Cells, Cultured, Disease Models, Animal, Fatty Liver, Alcoholic metabolism, Female, Humans, In Vitro Techniques, Interleukin-6 immunology, Interleukin-6 metabolism, Leukocyte Common Antigens immunology, Leukocyte Common Antigens metabolism, Liver metabolism, Liver Diseases, Alcoholic metabolism, Lymphocyte Activation, Malondialdehyde metabolism, Mice, Inbred C57BL, Phenotype, Spleen immunology, Spleen metabolism, T-Lymphocytes, Cytotoxic metabolism, T-Lymphocytes, Cytotoxic transplantation, Acetaldehyde immunology, Autoimmunity, Fatty Liver, Alcoholic immunology, Liver immunology, Liver Diseases, Alcoholic immunology, Malondialdehyde immunology, T-Lymphocytes, Cytotoxic immunology
- Abstract
Precision-cut liver slices (PCLSs) provide a novel model for studies of alcoholic liver disease (ALD). This is relevant, as in vivo ethanol exposure does not appear to generate significant liver damage in ethanol-fed mice, except in the National Institute on Alcohol Abuse and Alcoholism binge model of ALD. Previous studies have shown that the two metabolites of ethanol consumption, malondialdhyde (MDA) and acetaldehyde (AA), combine to form MDA-AA (MAA) adducts, which have been correlated with the development and progression of ALD. In this study, murine PCLSs were incubated with ethanol and examined for the production of MAA adducts. PCLSs were homogenized, and homogenates were injected into C57BL/6 mice. PCLSs from control-, pair-, and ethanol-fed animals served as targets in in situ cytotoxic assays using primed T cells from mice hyperimmunized with control or ethanol-exposed PCLS homogenates. A CD45.1/CD45.2 passive-transfer model was used to determine whether T cells from the spleens of mice hyperimmunized with PCLS ethanol-exposed homogenates trafficked to the liver. PCLSs incubated with ethanol generated MAA-modified proteins in situ. Cytotoxic (CD8
+ ) T cells from immunized mice killed naïve PCLSs from control- and pair-fed mice in vitro, a response that was blunted in PCLSs from ethanol-fed mice. Furthermore, CD45.1 CD8+ T cells from hyperimmunized mice trafficked to the liver but did not initiate liver damage. This study demonstrates that exposure to liver tissue damaged by ethanol mediates robust immune responses to well-characterized alcohol metabolites and native liver proteins in vitro. Moreover, although these proinflammatory T cells traffic to the liver, these responses appear to be dampened in vivo by locally acting pathways. NEW & NOTEWORTHY This study shows that the metabolites of ethanol and lipid breakdown produce malondialdehyde-acetaldehyde adducts in the precision-cut liver slice model system. Additionally, precision-cut liver slices exposed to ethanol and harboring malondialdehyde-acetaldehyde adducts generate liver-specific antibody and T cell responses in the spleens of naïve mice that could traffic to the liver.- Published
- 2018
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34. Malondialdehyde-Acetaldehyde (MAA) Protein Adducts Are Found Exclusively in the Lungs of Smokers with Alcohol Use Disorders and Are Associated with Systemic Anti-MAA Antibodies.
- Author
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Sapkota M, Burnham EL, DeVasure JM, Sweeter JM, Hunter CD, Duryee MJ, Klassen LW, Kharbanda KK, Sisson JH, Thiele GM, and Wyatt TA
- Subjects
- Acetaldehyde chemistry, Adult, Alcoholism complications, Female, Humans, Male, Malondialdehyde chemistry, Protein Binding, Proteins chemistry, Young Adult, Acetaldehyde metabolism, Alcoholism metabolism, Autoantibodies blood, Lung metabolism, Malondialdehyde metabolism, Proteins metabolism, Smokers, Smoking metabolism
- Abstract
Background: Malondialdehyde (MDA) and acetaldehyde (AA) exist following ethanol metabolism and tobacco pyrolysis. As such, lungs of individuals with alcohol use disorders (AUDs) are a target for the effects of combined alcohol and cigarette smoke metabolites. MDA and AA form a stable protein adduct, malondialdehyde-acetaldehyde (MAA) adduct, known to be immunogenic, profibrotic, and proinflammatory. MAA adduct is the dominant epitope in anti-MAA antibody formation. We hypothesized that MAA-adducted protein forms in lungs of those who both abuse alcohol and smoke cigarettes, and that this would be associated with systemically elevated anti-MAA antibodies., Methods: Four groups were established: AUD subjects who smoked cigarettes (+AUD/+smoke), smokers without AUD (-AUD/+smoke), AUD without smoke (+AUD/-smoke), and non-AUD/nonsmokers (-AUD/-smoke)., Results: We observed a significant increase in MAA adducts in lung cells of +AUD/+smoke versus -AUD/-smoke. No significant increase in MAA adducts was observed in -AUD/+smoke or in +AUD/-smoke compared to -AUD/-smoke. Serum from +AUD/+smoke had significantly increased levels of circulating anti-MAA IgA antibodies. After 1 week of alcohol that MAA-adducted protein is formed in the lungs of those who smoke cigarettes and abuse alcohol, leading to a subsequent increase in serum IgA antibodies., Conclusions: MAA-adducted proteins could play a role in pneumonia and other diseases of the lung in the setting of AUD and smoking., (Copyright © 2017 by the Research Society on Alcoholism.)
- Published
- 2017
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35. Emotional Benefits and Barriers of Psychological Services Scale: Initial construction and validation among African American women.
- Author
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Watson-Singleton NN, Okunoren O, LoParo D, and Hunter CD
- Subjects
- Adolescent, Adult, Counseling methods, Factor Analysis, Statistical, Female, Health Knowledge, Attitudes, Practice, Humans, Middle Aged, Reproducibility of Results, Young Adult, Black or African American psychology, Counseling standards, Emotions physiology, Patient Acceptance of Health Care psychology, Psychological Tests standards
- Abstract
The current study used the Health Belief Model to develop a measure that assessed the emotional benefits and barriers of professional psychological services in an African American women sample. Data from 251 African American women recruited from online organizations from across the United States (n = 164) and a Midwestern university psychology subject pool (n = 87) were used for exploratory factor analysis. Results revealed a 2-factor structure of the Emotional Benefits and Barriers of Psychological Services (EBBPS) Scale: Life Enhancement and Concerns about Distress, respectively. Confirmatory factor analysis was performed with data from 208 African American women who were recruited from a Midwestern university psychology subject pool (n = 81), Mturk (n = 104), and online organizations across the United States (n = 23). Results confirmed the EFA 2-factor model and demonstrated superior fit compared with a unidimensional model as well as a 3 factor model. Both factors exhibited excellent internal consistency. Construct validity was supported given that EBBPS factors were correlated with theoretically related constructs, like psychological help-seeking attitudes, intentions to seek counseling, and cultural identity, as well as uncorrelated with theoretically unrelated constructs, like psychological distress. These findings support the utility and cultural relevance of the EBBPS with African American women. (PsycINFO Database Record, ((c) 2017 APA, all rights reserved).)
- Published
- 2017
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36. Direct antioxidant properties of methotrexate: Inhibition of malondialdehyde-acetaldehyde-protein adduct formation and superoxide scavenging.
- Author
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Zimmerman MC, Clemens DL, Duryee MJ, Sarmiento C, Chiou A, Hunter CD, Tian J, Klassen LW, O'Dell JR, Thiele GM, Mikuls TR, and Anderson DR
- Subjects
- Albumins metabolism, Cell Survival drug effects, HEK293 Cells, Humans, NF-E2-Related Factor 2 metabolism, Protein Binding, Signal Transduction drug effects, Acetaldehyde metabolism, Free Radical Scavengers pharmacology, Malondialdehyde metabolism, Methotrexate pharmacology, Superoxides metabolism
- Abstract
Methotrexate (MTX) is an immunosuppressant commonly used for the treatment of autoimmune diseases. Recent observations have shown that patients treated with MTX also exhibit a reduced risk for the development of cardiovascular disease (CVD). Although MTX reduces systemic inflammation and tissue damage, the mechanisms by which MTX exerts these beneficial effects are not entirely known. We have previously demonstrated that protein adducts formed by the interaction of malondialdehyde (MDA) and acetaldehyde (AA), known as MAA-protein adducts, are present in diseased tissues of individuals with rheumatoid arthritis (RA) or CVD. In previously reported studies, MAA-adducts were shown to be highly immunogenic, supporting the concept that MAA-adducts not only serve as markers of oxidative stress but may have a direct role in the pathogenesis of inflammatory diseases. Because MAA-adducts are commonly detected in diseased tissues and are proposed to mitigate disease progression in both RA and CVD, we tested the hypothesis that MTX inhibits the generation of MAA-protein adducts by scavenging reactive oxygen species. Using a cell free system, we found that MTX reduces MAA-adduct formation by approximately 6-fold, and scavenges free radicals produced during MAA-adduct formation. Further investigation revealed that MTX directly scavenges superoxide, but not hydrogen peroxide. Additionally, using the Nrf2/ARE luciferase reporter cell line, which responds to intracellular redox changes, we observed that MTX inhibits the activation of Nrf2 in cells treated with MDA and AA. These studies define previously unrecognized mechanisms by which MTX can reduce inflammation and subsequent tissue damage, namely, scavenging free radicals, reducing oxidative stress, and inhibiting MAA-adduct formation., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2017
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- View/download PDF
37. The role of minority stress in second-generation Black emerging adult college students' high-risk drinking behaviors.
- Author
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Pittman DM, Cho Kim S, Hunter CD, and Obasi EM
- Subjects
- Acculturation, Adolescent, Adult, Black or African American statistics & numerical data, Female, Humans, Male, Minority Groups statistics & numerical data, Stress, Psychological epidemiology, Students statistics & numerical data, United States, Universities, Young Adult, Black or African American psychology, Alcohol Drinking in College psychology, Minority Groups psychology, Risk-Taking, Stress, Psychological psychology, Students psychology
- Abstract
Objective: This study used a minority stress framework to investigate the relationships between multiple stressors (e.g., general life stress, race related stress, and acculturative stress) and high-risk drinking behaviors in a sample of second-generation Black emerging adult college students across the United States., Method: Participants (n = 148) were recruited from U.S. colleges and universities as part of a large, multiwave cross-sectional study., Results: Findings from this study mirrored those in the extant literature: the positive relationship between race-related stress and high-risk drinking behaviors found in other marginalized groups. However, when all stressors were entered into the model, acculturative stress accounted for significant variance in high-risk drinking behaviors above and beyond general life and race-related stressors in second generation Black emerging adult college students., Conclusion: Findings underscore the need to better understand the influence of acculturative stress on high-risk drinking behaviors among second-generation Black emerging adult college students: an understudied population in both the acculturation and alcohol use literatures. Implications for future research and clinical practice are discussed. (PsycINFO Database Record, ((c) 2017 APA, all rights reserved).)
- Published
- 2017
- Full Text
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38. White fear, dehumanization, and low empathy: Lethal combinations for shooting biases.
- Author
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Mekawi Y, Bresin K, and Hunter CD
- Subjects
- Empathy, Ethnicity psychology, Asia, Eastern ethnology, Female, Humans, Individuality, Male, Minority Groups psychology, Minority Groups statistics & numerical data, Predictive Value of Tests, Racial Groups, Racism psychology, Students, Transgender Persons, United States ethnology, Young Adult, Black or African American psychology, Asian psychology, Dehumanization, Fear psychology, White People psychology
- Abstract
Objectives: A growing number of studies have documented the existence racial shooting biases against Black versus White targets (Correll et al., 2002). Little is known about individual differences that may moderate these biases. The goals of this study were to examine (a) whether White participants' fear of racial/ethnic minorities is associated with racial shooting biases, and (b) whether dehumanization and empathy moderate this effect., Method: Participants (N = 290) completed a dehumanization implicit association test and simulated shooting task, then reported their fear of racial minorities (i.e., White fear) and empathic ability., Results: We found that (a) individuals high in White fear showed a shooting bias, such that they had a lower threshold for shooting Black relative to White and East Asian targets, (b) Dehumanization moderated the White fear and shooting bias relation, such that individuals high in White fear and high in dehumanization had a significantly more liberal shooting threshold for Black versus White targets, and (c) Empathy moderated the White fear and shooting bias relation, such that people who were high in White fear and low in empathic ability had a more liberal shooting threshold for Black versus White targets. In sum, fearing racial/ethnic minorities can have devastating shooting bias outcomes for Black individuals, but this effect is stronger when people also dehumanize Black individuals, and weaker when people have high empathy., Conclusions: These findings contribute to the literature by identifying theory driven moderators that identify both risk and protective factors in predicting racial shooting biases. (PsycINFO Database Record, ((c) 2016 APA, all rights reserved).)
- Published
- 2016
- Full Text
- View/download PDF
39. Anxiety and depression among African American women: The costs of strength and negative attitudes toward psychological help-seeking.
- Author
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Watson NN and Hunter CD
- Subjects
- Adult, Anxiety epidemiology, Depression epidemiology, Female, Help-Seeking Behavior, Humans, Mental Health Services, Middle Aged, Regression Analysis, United States epidemiology, Young Adult, Black or African American psychology, Anxiety ethnology, Depression ethnology, Patient Acceptance of Health Care ethnology
- Abstract
The Strong Black Woman (SBW) race-gender schema prompts African American women to use self-reliance and self-silence as coping strategies in response to stressors. Utilizing the coping strategies associated with the SBW race-gender schema could trigger anxiety and depression symptoms that may intensify when coupled with negative attitudes toward professional psychological help. The present study investigated whether African American women's endorsement of the SBW race-gender schema predicted increased symptoms of anxiety and depression and whether attitudes toward professional psychological help-seeking intensified psychological distress. Data were collected from 95 participants ranging in age from 18 to 65. Hierarchical regression analysis demonstrated significant main effects for the SBW race-gender schema and greater anxiety and depression, respectively. Greater indifference to stigma, 1 dimension of help-seeking attitudes, predicted lower levels of anxiety. African American women's attitudes toward professional help-seeking did not moderate the associations between endorsement of the SBW race-gender schema and anxiety or depression, respectively. Finally, endorsement of the SBW race-gender schema was inversely and significantly associated with 2 facets of help-seeking attitudes: (a) psychological openness and (b) help-seeking propensity. Taken together, these findings provide empirical support for the role of cultural factors, like the SBW race-gender schema, in African American women's experience of psychological distress and potential underutilization of mental health services. Future research directions are discussed. (PsycINFO Database Record, ((c) 2015 APA, all rights reserved).)
- Published
- 2015
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40. Malondialdehyde-acetaldehyde adducts and anti-malondialdehyde-acetaldehyde antibodies in rheumatoid arthritis.
- Author
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Thiele GM, Duryee MJ, Anderson DR, Klassen LW, Mohring SM, Young KA, Benissan-Messan D, Sayles H, Dusad A, Hunter CD, Sokolove J, Robinson WH, O'Dell JR, Nicholas AP, Tuma DJ, and Mikuls TR
- Subjects
- Adult, Aged, Cross Reactions, Enzyme-Linked Immunosorbent Assay, Female, Humans, Immunohistochemistry, Male, Middle Aged, Osteoarthritis immunology, Peptides, Cyclic immunology, Synovial Membrane immunology, Acetaldehyde immunology, Arthritis, Rheumatoid immunology, Autoantibodies blood, Malondialdehyde immunology
- Abstract
Objective: Malondialdehyde-acetaldehyde (MAA) adducts are a product of oxidative stress associated with tolerance loss in several disease states. This study was undertaken to investigate the presence of MAA adducts and circulating anti-MAA antibodies in patients with rheumatoid arthritis (RA)., Methods: Synovial tissue from patients with RA and patients with osteoarthritis (OA) were examined for the presence of MAA-modified and citrullinated proteins. Anti-MAA antibody isotypes were measured in RA patients (n = 1,720) and healthy controls (n = 80) by enzyme-linked immunosorbent assay. Antigen-specific anti-citrullinated protein antibodies (ACPAs) were measured in RA patients using a multiplex antigen array. Anti-MAA isotype concentrations were compared in a subset of RA patients (n = 80) and matched healthy controls (n = 80). Associations of anti-MAA antibody isotypes with disease characteristics, including ACPA positivity, were examined in all RA patients., Results: Expression of MAA adducts was increased in RA synovial tissue compared to OA synovial tissue, and colocalization with citrullinated proteins was found. Increased levels of anti-MAA antibody isotypes were observed in RA patients compared to controls (P < 0.001). Among RA patients, anti-MAA antibody isotypes were associated with seropositivity for ACPAs and rheumatoid factor (P < 0.001) in addition to select measures of disease activity. Higher anti-MAA antibody concentrations were associated with a greater number of positive antigen-specific ACPA analytes (expressed at high titer) (P < 0.001) and a higher ACPA score (P < 0.001), independent of other covariates., Conclusion: MAA adduct formation is increased in RA and appears to result in robust antibody responses that are strongly associated with ACPAs. These results support speculation that MAA formation may be a cofactor that drives tolerance loss, resulting in the autoimmune responses characteristic of RA., (Copyright © 2015 by the American College of Rheumatology.)
- Published
- 2015
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41. Unique antibody responses to malondialdehyde-acetaldehyde (MAA)-protein adducts predict coronary artery disease.
- Author
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Anderson DR, Duryee MJ, Shurmur SW, Um JY, Bussey WD, Hunter CD, Garvin RP, Sayles HR, Mikuls TR, Klassen LW, and Thiele GM
- Subjects
- Aged, Biomarkers blood, Case-Control Studies, Coronary Artery Disease blood, Coronary Artery Disease diagnosis, Female, Humans, Male, Middle Aged, Plaque, Atherosclerotic blood, Plaque, Atherosclerotic immunology, Acetaldehyde immunology, Autoantibodies blood, Coronary Artery Disease immunology, Lipoproteins, LDL immunology, Malondialdehyde immunology
- Abstract
Malondialdehyde-acetaldehyde adducts (MAA) have been implicated in atherosclerosis. The purpose of this study was to investigate the role of MAA in atherosclerotic disease. Serum samples from controls (n = 82) and patients with; non-obstructive coronary artery disease (CAD), (n = 40), acute myocardial infarction (AMI) (n = 42), or coronary artery bypass graft (CABG) surgery due to obstructive multi-vessel CAD (n = 72), were collected and tested for antibody isotypes to MAA-modifed human serum albumin (MAA-HSA). CAD patients had elevated relative levels of IgG and IgA anti-MAA, compared to control patients (p<0.001). AMI patients had a significantly increased relative levels of circulating IgG anti-MAA-HSA antibodies as compared to stable angina (p<0.03) or CABG patients (p<0.003). CABG patients had significantly increased relative levels of circulating IgA anti-MAA-HSA antibodies as compared to non-obstructive CAD (p<0.001) and AMI patients (p<0.001). Additionally, MAA-modified proteins were detected in the tissue of human AMI lesions. In conclusion, the IgM, IgG and IgA anti-MAA-HSA antibody isotypes are differentially and significantly associated with non-obstructive CAD, AMI, or obstructive multi-vessel CAD and may serve as biomarkers of atherosclerotic disease.
- Published
- 2014
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42. Rules of engagement: predictors of Black Caribbean immigrants' engagement with African American culture.
- Author
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Joseph N, Watson NN, Wang Z, Case AD, and Hunter CD
- Subjects
- Adolescent, Adult, Black or African American psychology, Black or African American statistics & numerical data, Black People statistics & numerical data, Caribbean Region ethnology, Emigrants and Immigrants statistics & numerical data, Female, Humans, Male, Middle Aged, Racial Groups, Social Environment, Stress, Psychological psychology, United States, Young Adult, Acculturation, Black People ethnology, Black People psychology, Culture, Emigrants and Immigrants psychology
- Abstract
The cultural context in the United States is racialized and influences Black Caribbean immigrants' acculturation processes, but what role it plays in Black Caribbean immigrants' acculturation into specific facets of American society (e.g., African American culture) has been understudied in the field of psychology. The present study extends research on Black Caribbean immigrants' acculturative process by assessing how this group's experience of the racial context (racial public regard, ethnic public regard, and cultural race-related stress) influences its engagement in African American culture (i.e., adoption of values and behavioral involvement). Data were collected from 93 Black participants of Caribbean descent, ranging in age from 13 to 45 and analyzed using a stepwise hierarchical regression. The findings highlighted that when Black Caribbean-descended participants perceived that the public held a favorable view of their racial group they were more likely to engage in African American culture. In contrast, when participants perceived that the public held a favorable view of their ethnic group (e.g., Haitian) they were less likely to engage in African American culture. Furthermore, among participants experiencing low levels of cultural race-related stress, the associations between racial public regard and engagement with African American culture were amplified. However, for participants experiencing high cultural race-related stress, their engagement in African American culture did not change as a function of racial public regard. These findings may suggest that, for Black Caribbean immigrants, the experience of the racial context influences strategies that serve to preserve or bolster their overall social status and psychological well-being in the United States., (PsycINFO Database Record (c) 2013 APA, all rights reserved.)
- Published
- 2013
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43. Counterspaces: a unit of analysis for understanding the role of settings in marginalized individuals' adaptive responses to oppression.
- Author
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Case AD and Hunter CD
- Subjects
- Coercion, Female, Humans, Male, Personal Satisfaction, Self Concept, Adaptation, Psychological, Social Marginalization psychology
- Abstract
Research and theory on the intervening variables that enable individuals who experience marginalization and oppression to achieve well-being have historically relied on an individual level of analysis. Yet, there is a growing body of literature that highlights the roles that contexts play in facilitating processes that result in wellness among marginalized individuals. This paper proposes a conceptual framework that highlights a specific type of setting, referred to as "counterspaces," which promotes the psychological well-being of individuals who experience oppression. Counterspaces are theorized to enhance well-being by challenging deficit-oriented societal narratives concerning marginalized individuals' identities. The conceptual frame proposed here suggests that "challenging" can occur through at least three processes: (1) narrative identity work, (2) acts of resistance, and (3) direct relational transactions. This paper articulates each of these challenging processes. Additionally, the utility of using the Counterspaces framework for thinking critically about and investigating how settings-and the transactional processes that unfold within them-are associated with the promotion of psychological wellness for various marginalized populations is discussed.
- Published
- 2012
- Full Text
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44. Citrullinated mouse collagen administered to DBA/1J mice in the absence of adjuvant initiates arthritis.
- Author
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Thiele GM, Duryee MJ, Dusad A, Hunter CD, Lacy JP, Anderson DR, Wang D, O'Dell JR, Mikuls TR, and Klassen LW
- Subjects
- Animals, Antibodies immunology, Arthritis, Experimental immunology, Autoantigens chemistry, Citrulline chemistry, Collagen Type II chemistry, Disease Models, Animal, Freund's Adjuvant administration & dosage, Humans, Immunity, Male, Mice, Mice, Inbred DBA, Peptide Fragments chemistry, Peptide Fragments immunology, Arthritis, Experimental chemically induced, Arthritis, Rheumatoid immunology, Autoantigens administration & dosage, Collagen Type II administration & dosage, T-Lymphocytes immunology
- Abstract
Introduction: Citrullinated self-proteins are thought to be involved in the onset/progression of rheumatoid arthritis (RA). Numerous studies have been performed to look for the self-antigen that becomes citrullinated and induces RA. Importantly, these studies have been performed using citrullinated self-antigens injected into an animal model in the presence of a strong adjuvant in order to derive the response. However, to date no studies have been performed to determine if these phenotypes can be induced in the absence of an adjuvant., Methods: To investigate this possibility, mice were immunized with citrullinated or non-citrullinated mouse Type II collagen (Cit-Col or Col) in the presence or absence of Freund's Complete Adjuvant (FCA)., Results: An autoimmune-like RA response was observed in mice immunized with Cit-Col in the absence of FCA; by the increase in caliper score, visual observation, and micro-CT analysis of bone erosions. Antibody and T-cell responses were increased in the Cit-Col injected mice to Cit-Col as well as antibody to Anti-Citrullinated Peptide Antigens (ACPA) as determined by a commercially available test kit., Conclusions: Therefore, the use of citrullinated mouse collagen induces an autoimmune-like RA in the absence of an adjuvant. These data also suggest that citrullinate self-proteins may be potential molecular adjuvants that assist in driving an inflammatory response, that increases the production of PAD in joint tissue, resulting in the citrullination of other self-proteins to exacerbate the disease., (Copyright © 2012 Elsevier B.V. All rights reserved.)
- Published
- 2012
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45. Malondialdehyde-acetaldehyde adduct is the dominant epitope after MDA modification of proteins in atherosclerosis.
- Author
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Duryee MJ, Klassen LW, Schaffert CS, Tuma DJ, Hunter CD, Garvin RP, Anderson DR, and Thiele GM
- Subjects
- Acetaldehyde metabolism, Animals, Aorta immunology, Dihydropyridines immunology, Epitopes immunology, Male, Malondialdehyde immunology, Malondialdehyde metabolism, Mice, Mice, Inbred BALB C, Proteins chemistry, Rats, Rats, Sprague-Dawley, Atherosclerosis immunology, Dihydropyridines pharmacology, Malondialdehyde pharmacology
- Abstract
Antibodies to malondialdehyde (MDA)-modified macromolecules (adducts) have been detected in the serum of patients with atherosclerosis and correlate with the progression of this disease. However, the epitope and its formation have not been characterized. Studies have shown that excess MDA can be degraded to acetaldehyde, which combines with proteins to from a stable dihydropyridine adduct. To investigate, mice were immunized with MDA adducts in the absence of adjuvant and showed an increase in antibodies to MDA adducts and the carrier protein as the concentration of MDA was increased. In fact, a number of the commercially available antibodies to MDA-modified proteins were able to be inhibited by a chemical analogue, hexyl-MAA. Also, MDA-MAA adducts were detected in the serum and aortic tissue of JCR diabetic/atherosclerotic rats. These studies determined that commercially available antibodies to MDA predominantly react with the MAA adduct and are present in the JCR model of atherosclerosis in both the serum and the aortic tissue. Therefore, the immune response to MDA-modified proteins is most probably to the dihydropyridine structure (predominant epitope in MAA), which suggests that MAA adducts may play a role in the development and/or progression of atherosclerosis., (Copyright © 2010 Elsevier Inc. All rights reserved.)
- Published
- 2010
- Full Text
- View/download PDF
46. Alcohol metabolites and lipopolysaccharide: roles in the development and/or progression of alcoholic liver disease.
- Author
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Schaffert CS, Duryee MJ, Hunter CD, Hamilton BC 3rd, DeVeney AL, Huerter MM, Klassen LW, and Thiele GM
- Subjects
- Animals, Anti-Inflammatory Agents therapeutic use, Curcumin therapeutic use, Disease Progression, Ethanol pharmacology, Ethanol toxicity, Hepatocytes drug effects, Hepatocytes metabolism, Humans, Lipopolysaccharides metabolism, Liver drug effects, Liver metabolism, Liver Diseases, Alcoholic metabolism, Liver Diseases, Alcoholic physiopathology, Mice, Models, Animal, Ethanol metabolism, Lipopolysaccharides pharmacology, Liver Diseases, Alcoholic pathology
- Abstract
The onset of alcoholic liver disease (ALD) is initiated by different cell types in the liver and a number of different factors including: products derived from ethanol-induced inflammation, ethanol metabolites, and the indirect reactions from those metabolites. Ethanol oxidation results in the production of metabolites that have been shown to bind and form protein adducts, and to increase inflammatory, fibrotic and cirrhotic responses. Lipopolysaccharide (LPS) has many deleterious effects and plays a significant role in a number of disease processes by increasing inflammatory cytokine release. In ALD, LPS is thought to be derived from a breakdown in the intestinal wall enabling LPS from resident gut bacterial cell walls to leak into the blood stream. The ability of adducts and LPS to independently stimulate the various cells of the liver provides for a two-hit mechanism by which various biological responses are induced and result in liver injury. Therefore, the purpose of this article is to evaluate the effects of a two-hit combination of ethanol metabolites and LPS on the cells of the liver to increase inflammation and fibrosis, and play a role in the development and/or progression of ALD.
- Published
- 2009
- Full Text
- View/download PDF
47. An in vitro method of alcoholic liver injury using precision-cut liver slices from rats.
- Author
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Klassen LW, Thiele GM, Duryee MJ, Schaffert CS, DeVeney AL, Hunter CD, Olinga P, and Tuma DJ
- Subjects
- Adenosine Triphosphate metabolism, Alcohol Dehydrogenase metabolism, Animals, Cell Survival drug effects, Cytochrome P-450 CYP2E1 metabolism, In Vitro Techniques, Male, Oxidation-Reduction, Rats, Wistar, Triglycerides metabolism, Disease Models, Animal, Ethanol toxicity, Liver drug effects, Liver enzymology, Liver pathology, Liver Diseases, Alcoholic enzymology, Liver Diseases, Alcoholic etiology, Liver Diseases, Alcoholic pathology, Rats
- Abstract
Alcohol abuse results in liver injury, but investigations into the mechanism(s) for this injury have been hampered by the lack of appropriate in vitro culture models in which to conduct in depth and specific studies. In order to overcome these shortcomings, we have developed the use of precision-cut liver slices (PCLS) as an in vitro culture model in which to investigate how ethanol causes alcohol-induced liver injury. In these studies, it was shown that the PCLS retained excellent viability as determined by lactate dehydrogenase and adenosine triphosphate (ATP) levels over a 96-h period of incubation. More importantly, the major enzymes of ethanol detoxification; alcohol dehydrogenase, aldehyde dehydrogenase, and cytochrome P4502E1, remained active and PCLS readily metabolized ethanol and produced acetaldehyde. Within 24 h and continuing up to 96h the PCLS developed fatty livers and demonstrated an increase in the redox state. These PCLS secreted albumin, and albumin secretion was decreased by ethanol treatment. All of these impairments were reversed following the addition of 4-methylpyrazole, which is an inhibitor of ethanol metabolism. Therefore, this model system appears to mimic the ethanol-induced changes in the liver that have been previously reported in human and animal studies, and may be a useful model for the study of alcoholic liver disease.
- Published
- 2008
- Full Text
- View/download PDF
48. Scavenger receptors on sinusoidal liver endothelial cells are involved in the uptake of aldehyde-modified proteins.
- Author
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Duryee MJ, Freeman TL, Willis MS, Hunter CD, Hamilton BC 3rd, Suzuki H, Tuma DJ, Klassen LW, and Thiele GM
- Subjects
- Animals, Ethanol pharmacology, Male, Mice, Mice, Inbred ICR, Mice, Knockout, Rats, Rats, Wistar, Reverse Transcriptase Polymerase Chain Reaction, Serum Albumin, Bovine metabolism, Aldehydes metabolism, Endothelial Cells metabolism, Liver metabolism, Proteins metabolism
- Abstract
Scavenger receptors on sinusoidal liver endothelial cells (SECs) eliminate potentially harmful modified proteins circulating through the liver. It was shown recently that aldehyde-modified proteins bind to scavenger receptors and are associated with the development/progression of alcoholic liver diseases. For these studies, rat livers were perfused in situ with 125I-formaldehyde-bovine serum albumin (f-Alb) or 125I-malondialdehyde-acetaldehyde-bovine serum albumin (MAA-Alb) in the presence of known scavenger receptor ligands as inhibitors. Reverse transcription-polymerase chain reaction (RT-PCR) analysis and scavenger receptor Type A (SRA) knock-out mice were used to assess the role of these receptors in mediating immune responses. The degradation of 125I-f-Alb or 125I-MAA-Alb in whole livers and isolated SECs can be inhibited by known scavenger receptor ligands, including f-Alb, maleylated bovine albumin, and fucoidan. 125I-f-Alb could not be completely inhibited by MAA-Alb. In contrast, 125I-MAA-Alb was only partially inhibited with advanced glycosylated endproduct albumin. RT-PCR data show the presence of a number of scavenger receptors on SECs that may be responsible for the binding of MAA-modified proteins. SRA seems to be one of these receptors involved in the effects mediated by MAA-modified proteins. In a study using SRA knockout mice, it was shown that a decreased antibody response to MAA-Alb resulted. By RT-PCR, CD36, LOX-1, and SR-AI are the scavenger receptors most likely involved in the degradation of MAA-Alb.
- Published
- 2005
- Full Text
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49. Cognitive effects of life stress and learned helplessness.
- Author
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Yee PL, Edmondson B, Santoro KE, Begg AE, and Hunter CD
- Abstract
Abstract Stressful life events and learned helplessness attributional styles have been shown to impact a variety of personal outcomes. This study examined how these factors influence two classes of cognitive behaviors: the occurrence of intrusive thoughts and performance in memory and verbal-spatial reasoning tasks. Negative life change and attributions for negative events predicted different types of cognitive responses. Individuals reporting higher levels of life stress were more likely to experience distracting thoughts that were unrelated to the current task, whereas individuals with learned helplessness attributional styles tended to have more worrisome thoughts about their task performance. In general, individuals reporting high levels of negative life stress tended to perform more poorly in tasks, whereas individuals with learned helplessness attributional styles tended to perform better than those who did not share this explanatory style. These results suggest that life stress and attributional style have important influecnes on cognitive processes, and that a learned helplessness attributional style can have beneficial effects on behavior in some situations.
- Published
- 1996
- Full Text
- View/download PDF
50. A bibliography of writings concerning the Big Horn Medicine Wheel, Big Horn National Forest.
- Author
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Hunter CD
- Subjects
- History, Ancient, History, Early Modern 1451-1600, History, Medieval, History, Modern 1601-, United States, Medicine, Traditional history, Symbolism
- Published
- 1985
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