61 results on '"Carter, ML"'
Search Results
2. A note on the detection of the neurotoxin domoic acid in beach-stranded dosidicus gigas in the southern california bight
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Mazzillo, FFM, Staaf, DJ, Field, JC, Carter, ML, and Ohman, MD
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Fisheries ,Fisheries Sciences - Abstract
The first occurrence of the neurotoxin domoic acid (DA) in Humboldt squid (Dosidicus gigas) during a toxic Pseudo-nitzschia bloom in the Southern California Bight is reported. Bloom levels of cells with in the Pseudo-nitzschia delicatissima group were detected on 6 July 2009 at 4 nearshore collection sites in the Southern California Bight (Scripps Pier, Newport Pier, Goleta Pier and Sterns Wharf). Particulate DA was detected in all of these locations, except for Newport Pier. Stranded Humboldt squid were found south of the Scripps pier 5 days after the toxic bloom was detected. DA was measured using ELISA and low DA concentrations were detected in the stomach or mantle tissue of the stranded specimens. Stomach content analysis indicated that possible DA vectors to Humboldt squid included both pelagic (Pacifc hake, Merluccius products, and Pacific sardine, Sardinops sagax) and nearshore (pile surfperch, Damalichthys vacca, and shiner surfperch, Cymatogaster aggregata) fish species. Although low DA levels were detected in stranded squid specimens, neurological symptoms of DA toxicity were not observed and low DA concentrations alone may not have been the cause of the stranding. Further studies should focus on DA toxic effects in D. gigs to verify whether this pelagic predator can be affected by a toxin frequently detected in pelagic ecosystems influenced by the California Current System.
- Published
- 2011
3. Density driven headland retention in a strong upwelling system: Implications for larval transport
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Roughan, M, Mace, AJ, Largier, JL, Morgan, SG, Fisher, JL, and Carter, ML
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Geophysics ,Oceanography ,Physical Geography and Environmental Geoscience - Published
- 2023
4. Density driven headland retention in a strong upwelling system: Implications for larval transport
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Roughan, M, Mace, AJ, Largier, JL, Morgan, SG, Fisher, JL, and Carter, ML
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Geophysics ,Oceanography ,Physical Geography and Environmental Geoscience ,Physical geography and environmental geoscience - Published
- 2005
5. Environmental and ecological drivers of harmful algal blooms revealed by automated underwater microscopy
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Kenitz, KM, Kenitz, KM, Anderson, CR, Carter, ML, Eggleston, E, Seech, K, Shipe, R, Smith, J, Orenstein, EC, Franks, PJS, Jaffe, JS, Barton, AD, Kenitz, KM, Kenitz, KM, Anderson, CR, Carter, ML, Eggleston, E, Seech, K, Shipe, R, Smith, J, Orenstein, EC, Franks, PJS, Jaffe, JS, and Barton, AD
- Abstract
In recent years, harmful algal blooms (HABs) have increased in their severity and extent in many parts of the world and pose serious threats to local aquaculture, fisheries, and public health. In many cases, the mechanisms triggering and regulating HAB events remain poorly understood. Using underwater microscopy and Residual Neural Network (ResNet-18) to taxonomically classify imaged organisms, we developed a daily abundance record of four potentially harmful algae (Akashiwo sanguinea, Chattonella spp., Dinophysis spp., and Lingulodinium polyedra) and major grazer groups (ciliates, copepod nauplii, and copepods) from August 2017 to November 2020 at Scripps Institution of Oceanography pier, a coastal location in the Southern California Bight. Random Forest algorithms were used to identify the optimal combination of environmental and ecological variables that produced the most accurate abundance predictions for each taxon. We developed models with high prediction accuracy for A. sanguinea ((Formula presented.)), Chattonella spp. ((Formula presented.)), and L. polyedra ((Formula presented.)), whereas models for Dinophysis spp. showed lower prediction accuracy ((Formula presented.)). Offshore nutricline depth and indices describing climate variability, including El Niño Southern Oscillation, Pacific Decadal Oscillation, and North Pacific Gyre Oscillation, that influence regional-scale ocean circulation patterns and environmental conditions, were key predictor variables for these HAB taxa. These metrics of regional-scale processes were generally better predictors of HAB taxa abundances at this coastal location than the in situ environmental measurements. Ciliate abundance was an important predictor of Chattonella and Dinophysis spp., but not of A. sanguinea and L. polyedra. Our findings indicate that combining regional and local environmental factors with microzooplankton populations dynamics can improve real-time HAB abundance forecasts.
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- 2023
6. Density driven headland retention in a strong upwelling system: Implications for larval transport
- Author
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Roughan, M, Roughan, M, Mace, AJ, Largier, JL, Morgan, SG, Fisher, JL, Carter, ML, Roughan, M, Roughan, M, Mace, AJ, Largier, JL, Morgan, SG, Fisher, JL, and Carter, ML
- Published
- 2022
7. Spinal Cord Stimulation in Chronic Pain: A Review of the Evidence
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Carter Ml
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Blinding ,Central nervous system ,Pain ,Electric Stimulation Therapy ,Critical Care and Intensive Care Medicine ,law.invention ,Angina ,03 medical and health sciences ,0302 clinical medicine ,Randomized controlled trial ,law ,Outcome Assessment, Health Care ,medicine ,Humans ,Pain Management ,030212 general & internal medicine ,Randomized Controlled Trials as Topic ,Peripheral Vascular Diseases ,business.industry ,Chronic pain ,Spinal cord ,medicine.disease ,Anesthesiology and Pain Medicine ,medicine.anatomical_structure ,Complex regional pain syndrome ,Spinal Cord ,Anesthesia ,Chronic Disease ,Neuropathic pain ,business ,Low Back Pain ,030217 neurology & neurosurgery - Abstract
This review looks at the evidence for the effectiveness of spinal cord stimulation in various chronic pain states. Spinal cord stimulation can only be effective when appropriate dorsal column fibres in the spinal cord are preserved and able to be stimulated. Spinal cord stimulation has been shown to have little to offer for patients with some diagnoses. Although 50 to 60% of patients with failed back surgery syndrome obtain significant pain relief with this technique, the strength of the evidence available is insufficient to clearly advocate its use in all patients with this condition. Though limited in quantity and quality, better evidence exists for its use in neuropathic pain, complex regional pain syndrome, angina pectoris and critical limb ischaemia. There is a lack of high quality evidence relating to spinal cord stimulation due to difficulties in conducting randomized controlled trials in this area. Serious methodological problems are encountered in blinding, recruitment and assessment in nearly all published trials of spinal cord stimulation. Suggestions regarding appropriate methodologies for trials which would produce better quality evidence are summarized.
- Published
- 2004
8. MN20, a D2 cyclin, is transiently expressed in selected neural populations during embryogenesis
- Author
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Ross, ME, primary, Carter, ML, additional, and Lee, JH, additional
- Published
- 1996
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9. Maternal depressive symptoms in and beyond the perinatal period: Associations with infant and preschooler sleep.
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Carter ML, Paine SJ, Sweeney BM, Taylor JE, and Signal TL
- Abstract
Study Objectives: (1) To describe sleep in infancy and early childhood among children born to mothers with and without clinically significant depressive symptoms, and (2) to explore the relationships between maternal depressive symptoms and sleep patterns and problems during infancy and early childhood., Methods: Secondary analysis of longitudinal data from the Moe Kura: Mother and Child, Sleep and Wellbeing in Aotearoa/New Zealand study. Data was collected in pregnancy (T1), 12 weeks postpartum (T2), and 3 years post-birth (T3). Participants were 262 Māori and 594 non-Māori mother-child dyads. Chi-square and Independent T-tests measured bivariate associations between maternal mood (T1, T2, T3) and child sleep characteristics (T2, T3). Binary logistic regression models examined longitudinal and concurrent associations between maternal depressive symptoms and infant and preschooler sleep. Adjusted models accounted for key socio-demographic variables, as well as infant sleep variables in preschooler models., Results: Bivariate associations were found between prior and concurrent depressive symptomology and many of the infant and preschooler sleep outcomes. In adjusted models, prenatal depressive symptoms remained independently associated with shorter-than-recommended sleep durations in preschoolers. In these models, concurrent depression was also associated with night waking, night LSRSP, and perceived sleep problems at 12 weeks postpartum, and CSHQ-determined and perceived sleep problems at 3 years post birth., Conclusions: Longitudinal and cross-sectional associations were found between maternal depressive symptoms and child sleep. Sleep appears to be one pathway by which maternal depression confers risk for suboptimal child health outcomes. Findings support the need for earlier and better maternal mental health services., (© The Author(s) 2024. Published by Oxford University Press on behalf of Sleep Research Society.)
- Published
- 2024
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10. Editorial: Evolution and genomics of the Mycobacterium tuberculosis complex.
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Guimaraes AMS, Allen AR, and Price-Carter ML
- Abstract
Competing Interests: MP-C was employed by AgResearch Ltd. The remaining 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.
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- 2023
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11. Review of United States laws pertaining to the recovery and analysis of human skeletal remains.
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Carter ML, Newman JL, Seidemann RM, and Reedy EA
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- Forensic Medicine, Humans, Police, Texas, United States, Body Remains, Expert Testimony
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Human skeletal remains (HSR) are routinely excavated from archeological contexts and analyzed by experts in human osteology. Contrarily, HSR in medicolegal contexts are usually recovered by law enforcement officers and examined by pathologists with limited osteological training. To examine legal requirements for expertise, we reviewed laws in the United States regarding the recovery and analysis of HSR from archeological sites, unmarked graves, and medicolegal contexts. Of the 50 states, 19 (38%) have laws stating that an anthropologist with osteological training should be involved in the recovery or analysis of HSR from an archeological context. Fifteen of those 16 states have laws requiring a minimum level of education to be a qualified skeletal analyst. In contrast, only one state, Texas, requires an anthropologist who handles forensic cases to have a doctoral degree. Including Texas, only eight states (16%) have laws that encourage but do not mandate consultation with a forensic anthropologist for medicolegal skeletal cases. Louisiana and Washington have state-funded laboratories, expert forensic anthropologists, and effective protocols for handling forensic cases. Due process and human rights concerns at stake in criminal cases require that those recovering and analyzing modern HSR have an equal or higher level of expertise than those working with archeological remains. Yet, legislators assume that law enforcement and pathologists are adequately trained. Because court standards demand expert testimony based on accepted methodologies and standard levels of competency, forensic anthropologists have a professional responsibility to engage with lawmakers to draft legislation to ensure proper handling of all skeletal cases., (© 2022 American Academy of Forensic Sciences.)
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- 2022
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12. Emotional changes following discrimination induction in gender- and sexuality-diverse adolescents.
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Smith DM, Fox KR, Carter ML, Thoma BC, and Hooley JM
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- Adolescent, Female, Gender Identity, Heterosexuality, Humans, Infant, Newborn, Sexual Behavior, Self-Injurious Behavior psychology, Sexual and Gender Minorities
- Abstract
Sexual and gender minority (SGM)-identifying adolescents are particularly vulnerable to negative psychological outcomes, including engagement in nonsuicidal self-injury (NSSI). However, little is known about why these relationships exist. We used experimental methods to test the psychological mediation framework in an online sample of 328 adolescents who reported female sex at birth and a range of sexual and gender identities. Participants reported on depressive symptoms, self-criticism (both self-report and implicit), NSSI, and discrimination. They also completed a discrimination-based mood induction to test emotional reactivity. At baseline, SGM participants reported higher levels of implicit and self-reported self-criticism, depressive symptoms, discrimination, and higher rates of NSSI compared with cisgender, heterosexual participants (ps < .03). Following the discrimination induction, SGM-identifying participants exhibited larger emotional reactivity compared with cisgender heterosexual participants, as measured by change in negative mood, F(1, 326) = 7.33, p = .01, ηp2 = .02, and state self-criticism, F(1, 326) = 4.67, p = .03, ηp2 = .014, but not implicit affect toward the self. This effect was associated with baseline depressive symptoms, self-criticism, NSSI history, and discrimination. Post hoc analyses revealed that participants who tended to reframe experiences of discrimination as opportunities for growth exhibited attenuated emotional reactivity to the induction; findings remained significant after adjusting for SGM status and event severity (ps < .001). Results indicate that adolescents identifying as SGM may experience elevated psychological distress compared with their cisgender heterosexual peers and that stigma-related stressors may increase emotion dysregulation and maladaptive cognitive styles, paralleling previously proposed psychological mediation models. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
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- 2022
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13. Synthesis and Structure of Oxygen Deficient Lead-Technetium Pyrochlore, the First Example of a Valence V Technetium Oxide.
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Kennedy BJ, Ablott TA, Avdeev M, Carter ML, Losurdo L, Saura-Muzquiz M, Thorogood KJ, Ting J, Wallwork KS, Zhang Z, Zhu H, and Thorogood GJ
- Abstract
The structure of lead-technetium pyrochlore has been refined in space group F d 3 ¯ m with a = 10.36584(2) Å using a combination of synchrotron X-ray and neutron powder diffraction data and confirmed via Electron Diffraction. The oxide is found to be oxygen deficient with a stoichiometry of Pb
2 Tc2 O7-d . Displacive disorder of the Pb cations is evident from the refinements, as has been observed in Bi2 Tc2 O7-d . X-ray absorption spectroscopic measurements at the Tc K-edge demonstrate the valence of the Tc is greater than 4.0 as anticipated from the refined oxygen stoichiometry. Raman spectroscopy confirms the presence of disorder leading us to conclude that this pyrochlore is the first example of a valence V technetium oxide., 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 © 2021 Kennedy, Ablott, Avdeev, Carter, Losurdo, Saura-Muzquiz, Thorogood, Ting, Wallwork, Zhang, Zhu and Thorogood.)- Published
- 2021
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14. Recurrent microbial community types driven by nearshore and seasonal processes in coastal Southern California.
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Wilson JM, Chamberlain EJ, Erazo N, Carter ML, and Bowman JS
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- California, Chlorophyll A, RNA, Ribosomal, 16S genetics, Seasons, Microbiota genetics
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A multitude of concurrent biological and physical processes contribute to microbial community turnover, especially in highly dynamic coastal environments. Characterizing what factors contribute most to shifts in microbial community structure and the specific organisms that correlate with changes in the products of photosynthesis improves our understanding of nearshore microbial ecosystem functions. We conducted high frequency sampling in nearshore Southern California in order to capture sub-weekly microbial community dynamics. Microbial communities were characterized by flow cytometry and 16S rRNA gene sequencing, and placed in the context of physicochemical parameters. Within our time-series, season and nutrient availability corresponded to changes in dominant microbial community members. Concurrent aseasonal drivers with overlapping scales of variability were also apparent when we used network analysis to assess the microbial community as subsets of the whole. Our analyses revealed the microbial community as a mosaic, with overlapping groups of taxa that varied on different timescales and correlated with unique abiotic and biotic factors. Specifically, a subnetwork associated with chlorophyll a exhibited rapid turnover, indicating that ecologically important subsets of the microbial community can change on timescales different than and in response to factors other than those that govern turnover of most members of the assemblage., (© 2021 Society for Applied Microbiology and John Wiley & Sons Ltd.)
- Published
- 2021
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15. Marine algal toxins and their vectors in southern California cetaceans.
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Danil K, Berman M, Frame E, Preti A, Fire SE, Leighfield T, Carretta J, Carter ML, and Lefebvre K
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- Animals, California, Cetacea, Harmful Algal Bloom, Environmental Monitoring, Saxitoxin analysis
- Abstract
Published baseline data on biotoxin exposure in cetaceans is sparse but critical for interpreting mortality events as harmful algal blooms increase in frequency and duration. We present the first synthesis of domoic acid (DA), saxitoxin (STX), okadaic acid (OA), and microcystin detections in the feces and urine of stranded and bycaught southern California cetaceans, over an 18 year period (2001-2018), along with corresponding stomach content data. DA was detected in 13 out of 19 cetacean species, most often in harbor porpoise (Phocoena phocoena) (81.8%, n = 22) and long-beaked common dolphins (Delphinus delphis bairdii) (74%, n = 231). Maximum DA concentrations of 324,000 ng/g in feces and 271, 967 ng/ml in urine were observed in D. d. bairdii. DA was detected more frequently and at higher concentrations in male vs. female D. d. bairdii. Higher fecal DA concentrations in D. d. bairdii were associated with a greater proportion of northern anchovy (Engraulis mordax) in the diet, indicating it may be a primary vector of DA. Fecal DA concentrations for D. d. bairdii off Point Conception were greater than those from animals sampled off Los Angeles and San Diego counties, reflecting greater primary productivity and higher Pseudo-nitzschia spp. abundance in that region and a greater abundance of E. mordax in the diet. STX was detected at low levels (fecal max = 7.5 ng/g, urine max = 17 ng/ml) in 3.6% (n = 165) of individuals from 3 out of 11 species. The occurrence of E. mordax in 100% of the 3 examined stomachs suggests this species could be a primary vector of the detected STX. OA was detected in 2.4% of tested individuals (n = 85) at a maximum fecal concentration of 422.8 ng/g. Microcystin was detected in 14.3% (n = 7) of tested individuals with a maximum liver concentration of 96.8 ppb., (Published by Elsevier B.V.)
- Published
- 2021
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16. Comparative Genomics of Mycobacterium avium Subspecies Paratuberculosis Sheep Strains.
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Mizzi R, Timms VJ, Price-Carter ML, Gautam M, Whittington R, Heuer C, Biggs PJ, and Plain KM
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Mycobacterium avium subspecies paratuberculosis (MAP) is the aetiological agent of Johne's disease (JD), a chronic enteritis that causes major losses to the global livestock industry. Further, it has been associated with human Crohn's disease. Several strains of MAP have been identified, the two major groups being sheep strain MAP, which includes the Type I and Type III sub-lineages, and the cattle strain or Type II MAP lineage, of which bison strains are a sub-grouping. Major genotypic, phenotypic and pathogenic variations have been identified in prior comparisons, but the research has predominately focused on cattle strains of MAP. In countries where the sheep industries are more prevalent, however, such as Australia and New Zealand, ovine JD is a substantial burden. An information gap exists regarding the genomic differences between sheep strain sub-lineages and the relevance of Type I and Type III MAP in terms of epidemiology and/or pathogenicity. We therefore investigated sheep MAP isolates from Australia and New Zealand using whole genome sequencing. For additional context, sheep MAP genome datasets were downloaded from the Sequence Read Archive and GenBank. The final dataset contained 18 Type III and 16 Type I isolates and the K10 cattle strain MAP reference genome. Using a pan-genome approach, an updated global phylogeny for sheep MAP from de novo assemblies was produced. When rooted with the K10 cattle reference strain, two distinct clades representing the lineages were apparent. The Australian and New Zealand isolates formed a distinct sub-clade within the type I lineage, while the European type I isolates formed another less closely related group. Within the type III lineage, isolates appeared more genetically diverse and were from a greater number of continents. Querying of the pan-genome and verification using BLAST analysis revealed lineage-specific variations ( n = 13) including genes responsible for metabolism and stress responses. The genetic differences identified may represent important epidemiological and virulence traits specific to sheep MAP. This knowledge will potentially contribute to improved vaccine development and control measures for these strains., 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 © 2021 Mizzi, Timms, Price-Carter, Gautam, Whittington, Heuer, Biggs and Plain.)
- Published
- 2021
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17. "Identity confusion in complicated grief: A closer look": Correction.
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Bellet BW, LeBlanc NJ, Nizzi MC, Carter ML, van der Does FHS, Peters J, Robinaugh DJ, and McNally RJ
- Abstract
Reports an error in "Identity confusion in complicated grief: A closer look" by Benjamin W. Bellet, Nicole J. LeBlanc, Marie-Christine Nizzi, Mikaela L. Carter, Florentine H. S. van der Does, Jacqueline Peters, Donald J. Robinaugh and Richard J. McNally ( Journal of Abnormal Psychology , 2020[May], Vol 129[4], 397-407). In the original article, the following acknowledgment of funding was missing from the author note: "Donald J. Robinaugh's work on this article was supported by federal funding from the National Institute of Mental Health (Grant 1K23MH113805-01A1; principal investigator: Donald J. Robinaugh)." The online version of this article has been corrected. (The following abstract of the original article appeared in record 2020-23551-001). Complicated grief (CG) is characterized by a wide range of symptoms, including identity confusion or a sense that a part of oneself has died with the decedent. Although identity confusion is a commonly reported feature of CG, little is known about which specific aspects of self-concept are compromised. In the current study, we used qualitative coding methods to investigate which aspects of the sense of self differed between those with and without CG in a sample of 77 bereaved adults. Relative to individuals without CG, those with CG provided fewer descriptors of their self-concept overall (lower self-fluency), provided sets of descriptors that consisted of fewer categories (lower self-diversity), and had lower proportions of self-relevant preferences and activities. However, group differences were not observed for proportions of any other categories of self-concept descriptors, including references to the loss, the past, or distress-related self-statements. Directions for future research and clinical implications are discussed. (PsycInfo Database Record (c) 2020 APA, all rights reserved).
- Published
- 2020
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18. Longitudinal predictors of self-injurious thoughts and behaviors in sexual and gender minority adolescents.
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Smith DM, Wang SB, Carter ML, Fox KR, and Hooley JM
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- Adolescent, Female, Humans, Male, Prospective Studies, Risk Factors, Self-Injurious Behavior psychology, Sexual and Gender Minorities psychology, Suicidal Ideation, Suicide, Attempted psychology
- Abstract
Sexual and gender minority (SGM) populations are at increased risk for several negative psychological outcomes, including self-injury. Although correlates of self-injurious thoughts and behaviors (SITBs) have been identified, it is unclear which factors are prospective predictors of SITB engagement in SGM youth. The current study investigated an online sample of 252 SGM adolescents over a 6-month period. Participants reported attitudes based on SGM identity, depression, self-criticism, body image, family support and family strain, friend NSSI engagement, and experiences of everyday discrimination. Lasso and elastic net regularized logistic regressions were used to examine which baseline variables were associated with SITB engagement at follow-up. Models resulted in excellent predictive accuracy of nonsuicidal self-injury and suicidal ideation (mean Area Under the Receiving Operating Characteristics Curve [AUC] of 0.90 and 0.91), good predictive accuracy for suicide plans (mean AUC = 0.85), and fair predictive accuracy for suicidal behaviors (mean AUC = 0.78). Several variables emerged as prospectively related to SITB risk, with varied associations across different SITBs. Results suggest that minority-specific factors may predict SITBs in SGM adolescents. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
- Published
- 2020
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19. Distribution of dissolved iron and bacteria producing the photoactive siderophore, vibrioferrin, in waters off Southern California and Northern Baja.
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Yarimizu K, Cruz-López R, García-Mendoza E, Edwards M, Carter ML, and Carrano CJ
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- California, Citrates chemistry, Iron chemistry, Marinobacter metabolism, Mexico, Pyrrolidinones chemistry, Siderophores chemistry, Citrates biosynthesis, Iron metabolism, Marinobacter chemistry, Siderophores biosynthesis
- Abstract
Phytoplankton blooms can cause acute effects on marine ecosystems due either to their production of endogenous toxins or to their enormous biomass leading to major impacts on local economies and public health. Despite years of effort, the causes of these Harmful Algal Blooms are still not fully understood. Our hypothesis is that bacteria that produce photoactive siderophores may provide a bioavailable source of iron for phytoplankton which could in turn stimulate algal growth and support bloom dynamics. Here we correlate iron concentrations, phytoplankton cell counts, bacterial cell abundance, and copy numbers for a photoactive siderophore vibrioferrin biosynthesis gene in water samples taken from 2017 cruises in the Gulf of California, and the Pacific Ocean off the coast of northern Baja California as well as during a multiyear sampling at Scripps Pier in San Diego, CA. We find that bacteria producing the photoactive siderophore vibrioferrin, make up a surprisingly high percentage of total bacteria in Pacific/Gulf of California coastal waters (up to 9%). Vibroferrin's unique properties and the widespread prevalence of its bacterial producers suggest that it may contribute significantly to generating bioavailability of iron via photoredox reactions.
- Published
- 2019
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20. Predicting coastal algal blooms in southern California.
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McGowan JA, Deyle ER, Ye H, Carter ML, Perretti CT, Seger KD, de Verneil A, and Sugihara G
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- California, Humans, Phytoplankton growth & development, Plankton growth & development, Ecosystem, Environmental Monitoring methods, Eutrophication, Microalgae growth & development
- Abstract
The irregular appearance of planktonic algae blooms off the coast of southern California has been a source of wonder for over a century. Although large algal blooms can have significant negative impacts on ecosystems and human health, a predictive understanding of these events has eluded science, and many have come to regard them as ultimately random phenomena. However, the highly nonlinear nature of ecological dynamics can give the appearance of randomness and stress traditional methods-such as model fitting or analysis of variance-to the point of breaking. The intractability of this problem from a classical linear standpoint can thus give the impression that algal blooms are fundamentally unpredictable. Here, we use an exceptional time series study of coastal phytoplankton dynamics at La Jolla, CA, with an equation-free modeling approach, to show that these phenomena are not random, but can be understood as nonlinear population dynamics forced by external stochastic drivers (so-called "stochastic chaos"). The combination of this modeling approach with an extensive dataset allows us to not only describe historical behavior and clarify existing hypotheses about the mechanisms, but also make out-of-sample predictions of recent algal blooms at La Jolla that were not included in the model development., (© 2017 by the Ecological Society of America.)
- Published
- 2017
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21. Oxygen isotope ratios in primate bone carbonate reflect amount of leaves and vertical stratification in the diet.
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Carter ML and Bradbury MW
- Subjects
- Animals, Carbonates, Oxygen, Uganda, Carbon Isotopes, Diet, Oxygen Isotopes, Primates
- Abstract
The stable isotopic biogeochemistry of free-ranging primates is a unique tool to assess dietary and ecological adaptions among sympatric populations. The present study tested the hypothesis that oxygen isotopes in the bone carbonate of five primate and four ungulate species that live in Kibale National Park, Uganda, would show minimal variability since the species obtain water from a single water source. Bones were analyzed for stable carbon (δ(13) C) and oxygen (δ(18) O) isotope ratios. Results for apatite δ(13) C are consistent with all species feeding in a closed forest habitat and do not exhibit niche partitioning. δ(18) O values, in contrast, cluster by species and correlate positively with the relative contribution of leaves to the whole diet are likely also modified by vertical niche partitioning between taxa within the forest canopy. These results show that biochemical markers from naturally deceased primate remains can aid our understanding of how living animals exploit available resources. Am. J. Primatol. 78:1086-1097, 2016 © 2015 Wiley Periodicals, Inc., (© 2015 Wiley Periodicals, Inc.)
- Published
- 2016
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22. Evaluation of photo-reactive siderophore producing bacteria before, during and after a bloom of the dinoflagellate Lingulodinium polyedrum.
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Yarimizu K, Polido G, Gärdes A, Carter ML, Hilbern M, and Carrano CJ
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- Dinoflagellida genetics, Genes, Bacterial, Photochemical Processes, Phylogeny, Phytoplankton genetics, Siderophores genetics, Dinoflagellida physiology, Eutrophication, Phytoplankton physiology, Siderophores metabolism
- Abstract
Evidence is increasing for a mutualistic relationship between phytoplankton and heterotrophic marine bacteria. It has been proposed that bacteria producing photoactive iron binding compounds known as siderophores could play an important role in such mutualistic associations by producing bioavailable iron utilizable by phytoplankton and in exchange receive autotrophically derived DOM. In order to understand the potential role photoactive siderophores might be playing in bacterial-algal mutualism or marine biogeochemistry in general, it is important to be able to detect and quantify their presence in various environments. One approach to accomplish that end is to make use of high sensitivity genomics technology (qPCR) to search for siderophore biosynthesis genes related to the production of photoactive siderophores. In this way one can access their "biochemical potential" and utilize this information as a proxy for the presence of these siderophores in the marine environment. In this report we studied the correlation of the presence of bacteria producing one of the three photoactive siderophores relative to total bacterial and dinoflagellate numbers from surface water at the Scripps Pier before, during, and after fall bloom of the dinoflagellate Lingulodinium polyedrum. We believe that these findings will aid us in gauging the importance of photoactive siderophores in the marine environment and in harmful algal bloom dynamics in particular.
- Published
- 2014
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23. PCR-based allelic discrimination for glucose-6-phosphate dehydrogenase (G6PD) deficiency in Ugandan umbilical cord blood.
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Hsu J, Fink D, Langer E, Carter ML, Bengo D, Ndidde S, Slusher T, Ross JA, and Lund TC
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- Alleles, Developing Countries, Female, Gene Frequency, Genotype, Humans, Incidence, Infant, Newborn, Male, Mutation, Missense, Polymorphism, Single Nucleotide, Uganda epidemiology, Fetal Blood enzymology, Genotyping Techniques, Glycogen Storage Disease Type I diagnosis, Neonatal Screening methods, Real-Time Polymerase Chain Reaction methods
- Abstract
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common X-linked disorder in the world. G6PD deficiency puts children at risk for hyperbilirubinemia and kernicterus during the newborn period and an increased risk of severe hemolysis after exposure to many antimalarial medications. A laboratory diagnosis of G6PD deficiency is rare in the developing world due to limited resources. We developed a TaqMan-based allele-specific assay to rapidly determine rates of G6PD deficiency contributing alleles (G202A and A376G) in East Africa. We tested umbilical cord blood from 100 Ugandan newborns and found that the overall allele frequency of G202A was .13 and A376G was .32. The overall incidence of G6PD A- (G202A/A376G) was 6%; all A- variants were males. There was no correlation between G6PD deficiency and umbilical cord blood hemoglobin, white blood count, platelet count, or other hematologic parameters. Allele-specific PCR can serve as a rapid method to determine specific G6PD deficiency allele frequencies in a given population and as a diagnostic tool in a hospital setting in which laboratory resources are present.
- Published
- 2014
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24. A model of glucose-6-phosphate dehydrogenase deficiency in the zebrafish.
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Patrinostro X, Carter ML, Kramer AC, and Lund TC
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- Amino Acid Sequence, Animals, Glucosephosphate Dehydrogenase chemistry, Humans, Models, Animal, Molecular Sequence Data, Reactive Oxygen Species metabolism, Sequence Homology, Amino Acid, Glucosephosphate Dehydrogenase metabolism, Zebrafish metabolism
- Abstract
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common genetic defect and enzymopathy worldwide, affecting approximately 400 million people and causing acute hemolysis in persons exposed to prooxidant compounds such as menthol, naphthalene, antimalarial drugs, and fava beans. Mouse models have not been useful because of a lack of significant response to oxidative challenge. We turned to zebrafish (Danio rerio) embryos, which develop ex utero and are transparent, allowing visualization of hemolysis. We designed morpholinos to zebrafish g6pd that were effective in reducing gene expression as shown by Western blot and G6PD enzyme activity, resulting in a brisk hemolysis and pericardial edema secondary to anemia. Titration of the g6pd knockdown allowed us to generate embryos that displayed no overt phenotype until exposed to the prooxidant compounds 1-naphthol, menthol, or primaquine, after which they developed hemolysis and pericardial edema within 48-72 hours. We were also able to show that g6pd morphants displayed significant levels of increased oxidative stress compared with controls. We anticipate that this will be a useful model of G6PD deficiency to study hemolysis as well as oxidative stress that occurs after exposure to prooxidants, similar to what occurs in G6PD-deficient persons., (Copyright © 2013 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.)
- Published
- 2013
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- View/download PDF
25. Circadian regulation of chloroplast transcription in Chlamydomonas is accompanied by little or no fluctuation in RPOD levels or core RNAP activity.
- Author
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Kawazoe R, Mahan KM, Venghaus BE, Carter ML, and Herrin DL
- Subjects
- Blotting, Western, Chlamydomonas drug effects, Chlamydomonas physiology, Chloroplasts drug effects, Chloroplasts enzymology, Circadian Rhythm drug effects, Cycloheximide pharmacology, DNA-Directed RNA Polymerases isolation & purification, Photoperiod, RNA, Ribosomal, 16S genetics, Chlamydomonas enzymology, Chlamydomonas genetics, Chloroplasts genetics, Circadian Rhythm genetics, DNA-Directed RNA Polymerases metabolism, Sigma Factor metabolism, Transcription, Genetic drug effects
- Abstract
In Chlamydomonas growing under 24 h light-dark cycles, chloroplast transcription is under circadian clock control, and peaks early in the morning. The peak (but not trough) requires ongoing cytoplasmic translation, as it is sensitive to cycloheximide (CH). The chloroplast transcriptional apparatus in Chlamydomonas is simpler than in land plants, with only one type of RNA polymerase (RNAP, bacterial) and apparently only one sigma factor (RPOD). Core RNAP can be assayed in vitro with a non-sigma factor dependent template, and is sensitive to rifampicin. We developed a membrane-based assay for RNAP activity, and used it to determine that core activity is only weakly affected by pre-treating cells with CH. Moreover, core chloroplast RNAP activity was steady during a 24 h light-dark cycle. Levels of the sigma factor (RPOD) were examined using western blots, and found to fluctuate less than 25 % during light-dark cycles. These data indicate that circadian regulation of chloroplast transcription is distinct from regulation by sulfur availability, which involves significant changes in RPOD levels. The implications of this data for hypotheses that purport to explain the circadian control mechanism are discussed.
- Published
- 2012
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- View/download PDF
26. Lobeline attenuates neonatal ethanol-mediated changes in hyperactivity and dopamine transporter function in the prefrontal cortex in rats.
- Author
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Smith AM, Wellmann KA, Lundblad TM, Carter ML, Barron S, and Dwoskin LP
- Subjects
- Animals, Animals, Newborn, Female, Male, Prefrontal Cortex drug effects, Psychomotor Agitation etiology, Psychomotor Agitation prevention & control, Rats, Rats, Sprague-Dawley, Central Nervous System Depressants toxicity, Dopamine Plasma Membrane Transport Proteins metabolism, Ethanol toxicity, Ganglionic Stimulants pharmacology, Lobeline pharmacology, Prefrontal Cortex metabolism
- Abstract
Current therapies for attention deficit hyperactivity disorder (ADHD) have varying efficacy in individuals with fetal alcohol spectrum disorders (FASD), suggesting that alternative therapeutics are needed. Developmental exposure to ethanol produces changes in dopamine (DA) systems, and DA has also been implicated in ADHD pathology. In the current study, lobeline, which interacts with proteins in dopaminergic presynaptic terminals, was evaluated for its ability to attenuate neonatal ethanol-induced locomotor hyperactivity and alterations in dopamine transporter (DAT) function in striatum and prefrontal cortex (PFC). From postnatal days (PND) 1-7, male and female rat pups were intubated twice daily with either 3 g/kg ethanol or milk, or were not intubated (non-intubated control) as a model for "third trimester" ethanol exposure. On PND 21 and 22, pups received acute lobeline (0, 0.3, 1, or 3 mg/kg), and locomotor activity was assessed. On PND 23-25, pups again received an acute injection of lobeline (1 or 3 mg/kg), and DAT kinetic parameters (Km and V(max)) were determined. Results demonstrated that neonatal ethanol produced locomotor hyperactivity on PND 21 that was reversed by lobeline (1 and 3 mg/kg). Although striatal DAT function was not altered by neonatal ethanol or acute lobeline, neonatal ethanol exposure increased the V(max) for DAT in the PFC, suggesting an increase in DAT function in PFC. Lobeline ameliorated this effect on PFC V(max) at the same doses that decreased hyperactivity. Methylphenidate, the gold standard therapeutic for ADHD, was also evaluated for comparison with lobeline. Methylphenidate decreased DAT V(max) and Km in PFC from ethanol-treated pups. Thus, lobeline and methylphenidate differentially altered DAT function following neonatal ethanol exposure. Collectively, these findings provide support that lobeline may be a useful pharmacotherapy for some of the deficits associated with neonatal ethanol exposure., (Copyright © 2011. Published by Elsevier Ltd.)
- Published
- 2012
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27. Behavioral deficits and cellular damage following developmental ethanol exposure in rats are attenuated by CP-101,606, an NMDAR antagonist with unique NR2B specificity.
- Author
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Lewis B, Wellmann KA, Kehrberg AM, Carter ML, Baldwin T, Cohen M, and Barron S
- Subjects
- Animals, Animals, Newborn, Anxiety etiology, Anxiety prevention & control, Behavior, Animal drug effects, Cell Death drug effects, Disease Models, Animal, Female, Fetal Alcohol Spectrum Disorders pathology, Fetal Alcohol Spectrum Disorders physiopathology, Hippocampus pathology, Learning Disabilities etiology, Learning Disabilities prevention & control, Male, Motor Skills Disorders etiology, Motor Skills Disorders prevention & control, Neurons drug effects, Neurons pathology, Random Allocation, Rats, Rats, Sprague-Dawley, Alcoholic Neuropathy prevention & control, Excitatory Amino Acid Antagonists therapeutic use, Fetal Alcohol Spectrum Disorders drug therapy, Hippocampus drug effects, Neuroprotective Agents therapeutic use, Piperidines therapeutic use, Receptors, N-Methyl-D-Aspartate antagonists & inhibitors
- Abstract
NMDAR-mediated excitotoxicity has been implicated in some of the impairments following fetal ethanol exposure. Previous studies suggest that both neuronal cell death and some of the behavioral deficits can be reduced by NMDAR antagonism during withdrawal, including antagonism of a subpopulation of receptors containing NR2B subunits. To further investigate NR2B involvement, we selected a compound, CP-101,606 (CP) which binds selectively to NR2B/2B stoichiometries, for both in vitro and in vivo analyses. For the in vitro study, hippocampal explants were exposed to ethanol for 10 days and then 24 h following removal of ethanol, cellular damage was quantified via propidium iodide fluorescence. In vitro ethanol withdrawal-associated neurotoxicity was prevented by CP (10 and 25 nM). In vivo ethanol exposure was administered on PNDs 1-7 with CP administered 21 h following cessation. Activity (PNDs 20-21), motor skills (PNDs 31-33), and maze navigation (PNDs 43-44) were all susceptible to ethanol insult; treatment with CP (15 mg/kg) rescued these deficits. Our findings show that CP-101,606, a drug that blocks the NR2B/2B receptor, can reduce some of the damaging effects of "3rd trimester" alcohol exposure in our rodent model. Further work is clearly warranted on the neuroprotective potential of this drug in the developing brain., (Copyright © 2011 Elsevier Inc. All rights reserved.)
- Published
- 2012
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28. Structural phase transitions and magnetic order in SrTcO3.
- Author
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Thorogood GJ, Avdeev M, Carter ML, Kennedy BJ, Ting J, and Wallwork KS
- Abstract
The structure of the perovskite SrTcO(3) has been investigated using both synchrotron X-ray and neutron powder diffraction. At room temperature SrTcO(3) is orthorhombic as a consequence of cooperative tilting of the corner sharing TcO(6) octahedra. The tilts are sequentially removed as the sample is heated with the oxide displaying the sequence of structres Pnma→Imma→I4/mcm→Pm ̅3m. Neutron powder diffraction data collected in the temperature range 4-1023 K indicate that SrTcO(3) has G-type antiferromagnetic structure, in which each Tc moment is antiparallel to its six nearest neighbours, below ∼1000 K. The magnetic structure is collinear antiferromagnetic with the technetium moments parallel to c-axis and can be described by the propagation vector k = [0,0,0] and the basis vector (0,0,A(z)). The same magnetic structure is observed in each of the four crystal structures., (This journal is © The Royal Society of Chemistry 2011)
- Published
- 2011
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29. Serum-deprived human multipotent mesenchymal stromal cells (MSCs) are highly angiogenic.
- Author
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Oskowitz A, McFerrin H, Gutschow M, Carter ML, and Pochampally R
- Subjects
- Angiogenesis Inducing Agents pharmacology, Animals, Aorta drug effects, Cell Differentiation, Chick Embryo, Chorioallantoic Membrane blood supply, Chorioallantoic Membrane drug effects, Culture Media, Conditioned metabolism, Culture Media, Serum-Free metabolism, Humans, In Vitro Techniques, Multipotent Stem Cells cytology, Rats, Rats, Wistar, Stromal Cells cytology, Angiogenesis Inducing Agents metabolism, Multipotent Stem Cells metabolism, Neovascularization, Physiologic drug effects, Stromal Cells metabolism
- Abstract
Recent reports have indicated that mesenchymal stromal cells (MSCs) from bone marrow have a potential in vascular remodeling and angiogenesis. Here, we report a unique phenomenon that under serum-deprived conditions MSCs survive and replicate. Secretome analysis of MSCs grown under serum-deprived conditions (SD-MSCs) identified a significant upregulation of prosurvival and angiogenic factors including VEGF-A, ANGPTs, IGF-1, and HGF. An ex vivo rat aortic assay demonstrated longer neovascular sprouts generated from rat aortic rings cultured in SD-MSC-conditioned media compared to neovascular sprouts from aortas grown in MSC-conditioned media. With prolonged serum deprivation, a subpopulation of SD-MSCs began to exhibit an endothelial phenotype. This population expressed endothelial-specific proteins including VEGFR2, Tie2/TEK, PECAM/CD31, and eNOS and also demonstrated the ability to uptake acetylated LDL. SD-MSCs also exhibited enhanced microtubule formation in an in vitro angiogenesis assay. Modified chick chorioallantoic membrane (CAM) angiogenesis assays showed significantly higher angiogenic potential for SD-MSCs compared to MSCs. Analysis of CAMs grown with SD-MSCs identified human-specific CD31-positive cells in vascular structures. We conclude that under the stress of serum deprivation MSCs are highly angiogenic and a population of these cells has the potential to differentiate into endothelial-like cells., (Copyright © 2011 Elsevier B.V. All rights reserved.)
- Published
- 2011
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30. Antiferromagnetism in a technetium oxide. Structure of CaTcO3.
- Author
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Avdeev M, Thorogood GJ, Carter ML, Kennedy BJ, Ting J, Singh DJ, and Wallwork KS
- Abstract
The technetium perovskite CaTcO(3) has been synthesized. Combining synchrotron X-ray and neutron diffraction, we found that CaTcO(3) is an antiferromagnetic with a surprisingly high Neel temperature of ∼800 K. The transition to the magnetic state does not involve a structural change, but there is obvious magnetostriction. Electronic structure calculations confirm the experimental results.
- Published
- 2011
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31. High temperature magnetic ordering in the 4d perovskite SrTcO3.
- Author
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Rodriguez EE, Poineau F, Llobet A, Kennedy BJ, Avdeev M, Thorogood GJ, Carter ML, Seshadri R, Singh DJ, and Cheetham AK
- Abstract
We present evidence for possibly the highest magnetic ordering temperature in any compound without 3d transition elements. Neutron powder diffraction measurements, at both time-of-flight and constant wavelength sources, were performed on two independently prepared SrTcO3 powders. SrTcO3 adopts a distorted perovskite structure with G-type antiferromagnetic ordering and has a moment of 1.87(4)μB per Tc cation at room temperature with an extraordinarily high Néel point close to 750 °C. Electronic structure calculations reveal extensive mixing between the technetium 4d states and oxygen states proximal to the Fermi level. This hybridization leads to a close relationship between magnetic ordering temperature and moment formation in SrTcO3.
- Published
- 2011
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- View/download PDF
32. Stable carbon and nitrogen isotope enrichment in primate tissues.
- Author
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Crowley BE, Carter ML, Karpanty SM, Zihlman AL, Koch PL, and Dominy NJ
- Subjects
- Animals, Apatites chemistry, Body Size, Bone and Bones chemistry, Carbon Isotopes, Collagen chemistry, Female, Hair chemistry, Keratins chemistry, Male, Muscles chemistry, Nitrogen Isotopes, Primates anatomy & histology, Species Specificity, Diet, Primates metabolism
- Abstract
Isotopic studies of wild primates have used a wide range of tissues to infer diet and model the foraging ecologies of extinct species. The use of mismatched tissues for such comparisons can be problematic because differences in amino acid compositions can lead to small isotopic differences between tissues. Additionally, physiological and dietary differences among primate species could lead to variable offsets between apatite carbonate and collagen. To improve our understanding of the isotopic chemistry of primates, we explored the apparent enrichment (ε*) between bone collagen and muscle, collagen and fur or hair keratin, muscle and keratin, and collagen and bone carbonate across the primate order. We found that the mean ε* values of proteinaceous tissues were small (≤1‰), and uncorrelated with body size or phylogenetic relatedness. Additionally, ε* values did not vary by habitat, sex, age, or manner of death. The mean ε* value between bone carbonate and collagen (5.6 ± 1.2‰) was consistent with values reported for omnivorous mammals consuming monoisotopic diets. These primate-specific apparent enrichment values will be a valuable tool for cross-species comparisons. Additionally, they will facilitate dietary comparisons between living and fossil primates.
- Published
- 2010
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33. Proteomic analysis of germinating urediniospores of Phakopsora pachyrhizi, causal agent of Asian soybean rust.
- Author
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Luster DG, McMahon MB, Carter ML, Fortis LL, and Nuñez A
- Subjects
- Amino Acid Sequence, Electrophoresis, Gel, Two-Dimensional methods, Germination, Molecular Sequence Data, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods, Basidiomycota metabolism, Fungal Proteins metabolism, Plant Diseases microbiology, Proteome metabolism, Glycine max microbiology
- Abstract
Phakopsora pachyrhizi is an obligate pathogen that causes Asian soybean rust. Asian soybean rust has an unusually broad host range and infects by direct penetration through the leaf cuticle. In order to understand the early events in the infection process, it is important to identify and characterize proteins in P. pachyrhizi. Germination of the urediniospore is the first stage in the infection process and represents a critical life stage applicable to studies with this obligate pathogen. We have applied a 2-DE and MS approach to identify 117 proteins from the National Center of Biotechnology Information nonredundant protein database and a custom database of Basidiomycota EST sequences. Proteins with roles in primary metabolism, energy transduction, stress, cellular regulation and signaling were identified in this study. This data set is accessible at http://world-2dpage.expasy.org/repository/database=0018.
- Published
- 2010
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34. Skeletal pathology in Pan troglodytes schweinfurthii in Kibale National Park, Uganda.
- Author
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Carter ML, Pontzer H, Wrangham RW, and Peterhans JK
- Subjects
- Age Factors, Animals, Anthropometry, Bone and Bones injuries, Female, Male, Sex Factors, Uganda, Body Size physiology, Bone and Bones pathology, Pan troglodytes anatomy & histology
- Abstract
The ecological pressures shaping chimpanzee anatomy and behavior are the subject of much discussion in primatology and paleoanthropology, yet empirical data on fundamental parameters including body size, morbidity, and mortality are rare for wild chimpanzees. Here, we present skeletal pathology and body size data for 20 (19 crania, 12 postcrania) chimpanzees (Pan troglodytes schweinfurthii) from Kibale National Park, Uganda. We compare these data with other East African populations, especially Gombe National Park. Estimated body size for Kibale chimpanzees was similar to other East African populations and significantly larger than Gombe chimpanzees. The high rates of trauma and other skeletal pathology evident in the Kibale chimpanzee skeletons were similar to those in the Gombe skeletal sample. Much of the major skeletal trauma in the Kibale skeletons was attributable to falls, although other pathologies were noted as well, including apparent injuries from snares, degenerative arthritis, and minor congenital abnormalities., ((c) 2007 Wiley-Liss, Inc.)
- Published
- 2008
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35. Structure, circadian regulation and bioinformatic analysis of the unique sigma factor gene in Chlamydomonas reinhardtii.
- Author
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Carter ML, Smith AC, Kobayashi H, Purton S, and Herrin DL
- Abstract
In higher plants, the transcription of plastid genes is mediated by at least two types of RNA polymerase (RNAP); a plastid-encoded bacterial RNAP in which promoter specificity is conferred by nuclear-encoded sigma factors, and a nuclear-encoded phage-like RNAP. Green algae, however, appear to possess only the bacterial enzyme. Since transcription of much, if not most, of the chloroplast genome in Chlamydomonas reinhardtii is regulated by the circadian clock and the nucleus, we sought to identify sigma factor genes that might be responsible for this regulation. We describe a nuclear gene (RPOD) that is predicted to encode an 80 kDa protein that, in addition to a predicted chloroplast transit peptide at the N-terminus, has the conserved motifs (2.1- 4.2) diagnostic of bacterial sigma-70 factors. We also identified two motifs not previously recognized for sigma factors, adjacent PEST sequences and a leucine zipper, both suggested to be involved in protein-protein interactions. PEST sequences were also found in approximately 40% of sigma factors examined, indicating they may be of general significance. Southern blot hybridization and BLAST searches of the genome and EST databases suggest that RPODmay be the only sigma factor gene in C. reinhardtii. The levels of RPODmRNA increased 2- 3-fold in the mid-to-late dark period of light-dark cycling cells, just prior to, or coincident with, the peak in chloroplast transcription. Also, the dark-period peak in RPOD mRNA persisted in cells shifted to continuous light or continuous dark for at least one cycle, indicating that RPODis under circadian clock control. These results suggest that regulation of RPODexpression contributes to the circadian clock's control of chloroplast transcription.
- Published
- 2004
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36. Perception of sports photographs: a multidimensional scaling analysis.
- Author
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Carter ML, Valenti SS, and Goldberg RF
- Subjects
- Adolescent, Adult, Female, Humans, Male, Perception, Photography standards, Sports
- Abstract
Some sports photographs are remarkable for how animate they appear, whereas others seem particularly static or frozen. To explore the aspects of still photographs that might produce a sense of action, 34 observers viewed all possible pairs of 14 previously published images depicting sports figures in action and were asked to judge their similarity under two conditions, image-focus (how similar are the images) or movement-focus (how similar is the type of movement). A separate group of observers also rated each image on eight scales. Multidimensional scaling analyses suggested that in the image-focus condition, subjects tended to organize their judgments around three general dimensions, e.g., on-ground versus off-ground, while in the movement-focus condition the subjects were more likely to cluster the images along the lines of the particular activity, throwing, running, or jumping. We discuss the problem of movement depiction in sports photographs and make suggestions for research on the effects of facial expressions, muscular strain, and amount of limb extension.
- Published
- 2001
- Full Text
- View/download PDF
37. Cerebellar histogenesis is disturbed in mice lacking cyclin D2.
- Author
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Huard JM, Forster CC, Carter ML, Sicinski P, and Ross ME
- Subjects
- Aging, Animals, Apoptosis, Cell Cycle, Cell Differentiation, Cell Division, Cerebellum pathology, Crosses, Genetic, Cyclin D2, Cyclins deficiency, Cyclins genetics, Embryonic and Fetal Development, Heterozygote, Interneurons cytology, Interneurons pathology, Interneurons physiology, Mice, Mice, Inbred C57BL, Mice, Knockout, Nerve Tissue Proteins deficiency, Nerve Tissue Proteins genetics, Neurons cytology, Neurons pathology, Cerebellum embryology, Cerebellum growth & development, Cyclins physiology, Gene Expression Regulation, Developmental, Nerve Tissue Proteins physiology, Neurons physiology
- Abstract
Formation of brain requires deftly balancing primary genesis of neurons and glia, detection of when sufficient cells of each type have been produced, shutdown of proliferation and removal of excess cells. The region and cell type-specific expression of cell cycle regulatory proteins, such as demonstrated for cyclin D2, may contribute to these processes. If so, regional brain development should be affected by alteration of cyclin expression. To test this hypothesis, the representation of specific cell types was examined in the cerebellum of animals lacking cyclin D2. The loss of this cyclin primarily affected two neuronal populations: granule cell number was reduced and stellate interneurons were nearly absent. Differences between null and wild-type siblings were obvious by the second postnatal week. Decreases in granule cell number arose from both reduction in primary neurogenesis and increase in apoptosis of cells that fail to differentiate. The dearth of stellate cells in the molecular layer indicates that emergence of this subpopulation requires cyclin D2 expression. Surprisingly, Golgi and basket interneurons, thought to originate from the same precursor pool as stellate cells, appear unaffected. These results suggest that cyclin D2 is required in cerebellum not only for proliferation of the granule cell precursors but also for proper differentiation of granule and stellate interneurons.
- Published
- 1999
- Full Text
- View/download PDF
38. Postischemic diazepam is neuroprotective in the gerbil hippocampus.
- Author
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Schwartz RD, Huff RA, Yu X, Carter ML, and Bishop M
- Subjects
- Animals, Body Temperature, Brain Ischemia metabolism, Brain Ischemia pathology, Bridged Bicyclo Compounds metabolism, Cell Survival drug effects, Gerbillinae, Hippocampus pathology, Hippocampus physiopathology, Male, Motor Activity drug effects, Rectum, Brain Ischemia physiopathology, Bridged Bicyclo Compounds, Heterocyclic, Diazepam pharmacology, Hippocampus drug effects
- Abstract
In this study, we address the hypothesis that enhancement of gamma-aminobutyric acid (GABA) neurotransmission following an ischemic episode is neuroprotective in the hippocampus. Mongolian gerbils were subjected to transient forebrain ischemia for 5 min by occlusion of the carotid arteries and then administered diazepam (10 mg/kg i.p.) 30 min or 30 and 90 min following ischemia. Diazepam produced a significant decrease in both rectal and brain temperature (4-6 degrees C) in the sham and ischemic gerbils. 1 day following the onset of reperfusion, diazepam substantially reduced the hyperactivity normally induced by the ischemic episode. 7 days later, neuronal viability in the hippocampus was assessed. The single dose of diazepam completely protected the CA1 pyramidal cells of the hippocampus in 62% of the gerbils and the double dose of diazepam completely protected CA1 pyramidal neurons in 67% of the gerbils. There was a significant correlation between the degree of pyramidal cell degeneration in the CA1 area of the hippocampus measured 7 days following ischemia and the degree of hyperactivity measured 1 day following ischemia. Diazepam also prevented the loss of [35S]t-butylbicyclophosphorothionate ([35S]TBPS) binding to GABA-gated chloride channels in the dendritic fields of the CA1 area of the hippocampus. Our findings support the hypothesis that enhancement of GABA neurotransmission following an ischemic event may offset neuronal excitability and prevent neuronal death in specific brain regions. We conclude that GABA-enhancing drugs, such as diazepam, are attractive candidates as neuroprotective agents following ischemic insults.
- Published
- 1994
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- View/download PDF
39. Non-haematological toxicity limiting the application of sequential high dose chemotherapy in patients with advanced breast cancer.
- Author
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Pittman KB, To LB, Bayly JL, Olweny CL, Abdi EA, Carter ML, Malycha P, Gill PG, Walsh J, and Ward GG
- Subjects
- Adult, Antineoplastic Combined Chemotherapy Protocols administration & dosage, Blood Transfusion, Combined Modality Therapy, Female, Hematopoietic Stem Cell Transplantation, Humans, Middle Aged, Transplantation, Autologous, Antineoplastic Combined Chemotherapy Protocols adverse effects, Bone Marrow Transplantation, Breast Neoplasms drug therapy, Breast Neoplasms surgery
- Abstract
A programme of repeated high dose chemotherapy for advanced breast cancer was developed using (1) cyclophosphamide 4 g/m2 followed by autologous peripheral blood stem cell (PBSC) collection; (2) three cycles of conventional dose chemotherapy; (3) high dose cyclophosphamide, cisplatin, and carmustine with PBSC rescue; and (4) high dose etoposide and melphalan with PBSC rescue. Fifteen eligible patients had advanced poor prognosis breast cancer either at initial diagnosis (one patient) or at relapse (14 patients). During the course of the protocol, there were three treatment related deaths, two patient withdrawals due to debilitating toxicity, five patient withdrawals due to disease progression, and one patient withdrawal due to inadequate collection of PBSC. The remaining four patients did not complete the planned protocol as the programme was terminated because of the unacceptable morbidity and mortality. They were treated with an alternative high dose chemotherapy protocol which was well tolerated. This study highlights the significant problems associated with a complex sequential high dose chemotherapy regimen. Cyclophosphamide mobilized PBSC infused following high dose chemotherapy enables rapid haematological recovery. However the non-haematological toxicity following high dose chemotherapy regimens is often severe and may limit the application of certain sequential high dose chemotherapy combinations in patients with breast cancer.
- Published
- 1992
40. Bacteraemia and insertion of laryngeal mask airways.
- Author
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Stone JM, Karalliedde LD, Carter ML, and Cumerland NS
- Subjects
- Humans, Prospective Studies, Random Allocation, Bacteremia etiology, Larynx, Masks
- Published
- 1992
- Full Text
- View/download PDF
41. Effect of pretreatment with oral pyridostigmine.
- Author
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Carter ML and Karalliedde L
- Subjects
- Drug Interactions, Humans, Military Personnel, Neuromuscular Junction drug effects, Pyridostigmine Bromide pharmacology, Vecuronium Bromide pharmacology
- Published
- 1992
- Full Text
- View/download PDF
42. Carbon localisation of impalpable mammographic abnormalities.
- Author
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Langlois SL and Carter ML
- Subjects
- Biopsy, Breast Neoplasms diagnosis, Breast Neoplasms surgery, Female, Humans, Palpation, Prospective Studies, Breast Neoplasms diagnostic imaging, Carbon, Mammography methods, Stereotaxic Techniques
- Abstract
A prospective study was undertaken to assess the usefulness, safety and cost-effectiveness of stereotactically guided carbon localisation of impalpable breast lesions. Fifty six lesions in 53 patients were localised by this method, some in combination with fine-needle aspiration and hookwire localisation. Some modification of the study was required due to ready acceptance of the technique by surgeons, who preferred carbon to hookwire localisation. The technique was proven to be safe and accurate, and highly acceptable to patients, referring clinicians and radiology staff. It is now the preferred procedure for localising impalpable breast lesions prior to excision biopsy.
- Published
- 1991
- Full Text
- View/download PDF
43. Management of sucking chest wounds.
- Author
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Carter ML
- Subjects
- Drainage instrumentation, Humans, Military Personnel, Occlusive Dressings, Thoracic Injuries therapy, Wounds, Penetrating therapy
- Published
- 1990
44. Rare structural variants of human and murine uroporphyrinogen I synthase.
- Author
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Meisler MH and Carter ML
- Subjects
- Animals, Erythrocytes enzymology, Hot Temperature, Humans, Hydroxymethylbilane Synthase blood, Isoelectric Point, Mice genetics, Protein Denaturation, Species Specificity, Ammonia-Lyases genetics, Hydroxymethylbilane Synthase genetics, Isoenzymes genetics
- Abstract
An isoelectric focusing method for detection of structural variants of the enzyme uroporphyrinogen I synthase [porphobilinogen ammonia-lyase (polymerizing), EC 4.3.1.8] in mammalian tissues has been developed. Mouse and human erythrocytes contain one or two major isozymes of uroporphyrinogen I synthase, respectively. Other tissues contain a set of more acidic isozymes that are encoded by the same structural gene as the erythrocyte isozymes. Mouse populations studied with this method were monomorphic for uroporphyrinogen I synthase, with the exception of one feral mouse population. The pedigree of a human family with a rare structural variant is consistent with autosomal linkage of the structural gene. This system provides a convenient isozyme marker for genetic studies and will facilitate determination of the chromosomal location of the uroporphyrinogen I synthase locus.
- Published
- 1980
- Full Text
- View/download PDF
45. Conservative treatment of breast cancer--where should the booster dose go?
- Author
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Denham JW, Carter ML, and Gill PG
- Subjects
- Breast Neoplasms surgery, Combined Modality Therapy, Female, Humans, Breast Neoplasms radiotherapy, Radiotherapy methods
- Published
- 1988
- Full Text
- View/download PDF
46. Bradycardia after the use of atracurium.
- Author
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Carter ML
- Subjects
- Adult, Aged, Atracurium, Atropine therapeutic use, Female, Humans, Intraoperative Complications drug therapy, Middle Aged, Anesthesia, General adverse effects, Bradycardia chemically induced, Isoquinolines adverse effects, Neuromuscular Blocking Agents adverse effects
- Abstract
Four cases of severe bradycardia developed during surgery in patients given the neuromuscular blocking agent atracurium as part of the anaesthesia. In all cases sinus rhythm was restored by giving intravenous atropine. It is recommended that in all operations in which vagal stimulation is expected patients should be given atropine as part of the premedication or induction sequence and should undergo full electrocardiographic monitoring during surgery.
- Published
- 1983
- Full Text
- View/download PDF
47. Effect of repeated laparoscopic surgery on the bovine estrous cycle.
- Author
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Carter ML, Dierschke DJ, and Hauser ER
- Abstract
The effects of repeated laparoscopic surgery on the length of the bovine estrous cycle, estrus, ovulation and corpus luteum function were determined after one estrous cycle of normal duration (18 to 24 days). Five, Angus x Hereford cows were subjected to laparoscopy on days 5, 13, 18 and 20 (estrus = day 0) of the subsequent cycle. Blood was collected daily during the cycle in which laparoscopy was performed (surgical cycle) and during the next cycle (postsurgical cycle). Lengths of the surgical and postsurgical cycles (22.3 +/- .5 days and 21.5 +/- .6 days, respectively) did not differ (P>.05) from that of the presurgical cycle (21.8 +/- .2 days). Average concentrations (ng/ml) of LH and progesterone in serum were similar during the surgical and postsurgical cycles (1.2 +/- .1, 2.2 +/- .2 vs 1.3 +/- .2 and 2.3 +/- .1). Progesterone concentrations remained above 1 ng/ml for 17 and 16 days during the surgical and postsurgical cycles, respectively. A pre-ovulatory rise in LH, along with estrus and ovulation was confirmed in all animals. Follicular development, characterized by follicular volume, increased progressively from days 5 to 20, with the largest increase occurring between days 13 and 18. These results indicate that laparoscopy, used at the times and frequency specified, does not alter reproductive function of cyclic cows and can provide information on ovarian activity.
- Published
- 1981
- Full Text
- View/download PDF
48. The assessment of thought deficit in psychotic unipolar depression and chronic paranoid schizophrenia.
- Author
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Carter ML
- Subjects
- Adult, Chronic Disease, Cognition Disorders, Depressive Disorder diagnosis, Diagnosis, Differential, Female, Hospitalization, Humans, Male, Psychometrics, Schizophrenia, Paranoid diagnosis, Thinking, Depressive Disorder psychology, Psychological Tests, Schizophrenia, Paranoid psychology
- Abstract
In order to evaluate thought disorder in a nonschizophrenic psychotic group, psychotic depressives were compared with chronic paranoid schizophrenics and normal control subjects on two assessments of thought pathology. The data indicate that: a) psychotic depressives show thought deficits in the same areas as chronic paranoid schizophrenics, and b) idiosyncratic thinking is the single most prominent thought disorder in both psychotic groups. Certain subtypes of thought disorder may be characteristic of psychosis in general rather than of any specific diagnostic category. A psychoticism profile would include idiosyncratic thinking, restricted abstracting ability, linguistic errors, content deficit, intermixing, and loss of goal.
- Published
- 1986
- Full Text
- View/download PDF
49. The selection of cases for wedge excision followed by radiotherapy as the treatment of their primary breast cancer.
- Author
-
Denham JW and Carter ML
- Subjects
- Breast Neoplasms radiotherapy, Cobalt therapeutic use, Combined Modality Therapy, Female, Humans, Postoperative Care, Radioisotope Teletherapy, Radiotherapy adverse effects, Radiotherapy Dosage, Radiotherapy, High-Energy, Breast Neoplasms therapy, Mastectomy methods
- Published
- 1986
- Full Text
- View/download PDF
50. Evidence that physiologic levels of circulating estrogens and neonatal sex-imprinting modify postpubertal hepatic microsomal 3-hydroxy-3-methylglutaryl coenzyme A reductase activity.
- Author
-
Carlson SE, Mitchell AD, Carter ML, and Goldfarb S
- Subjects
- Animals, Animals, Newborn, Body Weight, Castration, Estradiol pharmacology, Estrus, Female, Imprinting, Psychological, Male, Pregnancy, Rats, Sex Factors, Testosterone pharmacology, Estrogens blood, Hydroxymethylglutaryl CoA Reductases metabolism, Microsomes, Liver enzymology, Sexual Maturation
- Abstract
Intact, but sham-operated female rats had 2- to 3-fold higher levels of hepatic 3-hydroxy-3-methylglutaryl CoA reductase activity than their male counterparts (15--21.5 vs. 6.7--8.7 nmol mevalonate/mg protein per h). The activity of the hepatic enzyme declined to about the same relative degree (40--60%) in male and female rats that were gonadectomized after puberty (53 days of age) and killed 5 weeks later. Implantation of silastic capsules containing 17 beta-estradiol increased the level of hepatic 3-hydroxy-3-methylglutaryl CoA reductase to levels found in sham-operated controls. In rats that were gonadectomized in infancy (12 h old) and killed 7--8 weeks later, the level of enzyme activity was not altered in females, but it was increased from 60--240% in males. Consequently, following neonatal gonadectomy, male-female differences in enzyme activity were no longer apparent. Implantation of silastic capsules containing estradiol in neonatally gonadectomized rats resulted in a doubling of enzyme activity in both males and females. Ovariectomy reduced plasma estrogen levels, but implantation of estradiol in gonadectomized males and females increased the hormone level to that found in sham-operated females. Thus, the results strongly suggest a role for physiologic levels of estrogen as a positive effector of 3-hydroxy-3-methylglutaryl CoA reductase activity. Neonatal sex imprinting also appears to modulate the enzyme activity since sex-mediated differences are effaced by gonadectomy in infancy, but not by gonadectomy following puberty.
- Published
- 1980
- Full Text
- View/download PDF
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