14 results on '"Longo J"'
Search Results
2. 17-2 - Facteurs associés au retard de diagnostic de la tuberculose pulmonaire à bacilloscopie positive à Bangui, Centrafrique
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Woromogo, S.H., De Dieu Longo, J., Saint Calvaire Diemer, H., and Grezenguet, G.
- Abstract
Un cas de tuberculose pulmonaire bactériologiquement confirmée (TPB+) non traitée, constitue un réservoir pour la transmission de la maladie. Cette étude avait pour objectif d’évaluer le délai et d'identifier les déterminants du retard diagnostic de la TPB+ dans les centres de diagnostic et de traitement de la tuberculose (CDT) à Bangui.
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- 2024
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3. Dietary Restriction Enhances CD8⁺ T Cell Ketolysis to Limit Exhaustion and Boost Anti-Tumor Immunity.
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Oswald BM, DeCamp LM, Longo J, Dahabieh MS, Bunda N, Ma S, Watson MJ, Sheldon RD, Vincent MP, Johnson BK, Ellis AE, Soper-Hopper MT, Isaguirre CN, Shen H, Williams KS, Crawford PA, Kaech S, Jang HJ, Krawczyk CM, and Jones RG
- Abstract
Reducing calorie intake without malnutrition limits tumor progression but the underlying mechanisms are poorly understood. Here we show that dietary restriction (DR) suppresses tumor growth by enhancing CD8
+ T cell-mediated anti-tumor immunity. DR reshapes CD8+ T cell differentiation within the tumor microenvironment (TME), promoting the development of effector T cell subsets while limiting the accumulation of exhausted T (Tex) cells, and synergizes with anti-PD1 immunotherapy to restrict tumor growth. Mechanistically, DR enhances CD8+ T cell metabolic fitness through increased ketone body oxidation (ketolysis), which boosts mitochondrial membrane potential and fuels tricarboxylic acid (TCA) cycle-dependent pathways essential for T cell function. T cells deficient for ketolysis exhibit reduced mitochondrial function, increased exhaustion, and fail to control tumor growth under DR conditions. Our findings reveal a critical role for the immune system in mediating the anti-tumor effects of DR, highlighting nutritional modulation of CD8+ T cell fate in the TME as a critical determinant of anti-tumor immunity.- Published
- 2024
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4. An alternative route for β-hydroxybutyrate metabolism supports fatty acid synthesis in cancer cells.
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Kaluba FC, Rogers TJ, Jeong YJ, Waldhart A, Sokol KH, Lee CJ, Daniels SR, Longo J, Johnson A, Sheldon RD, Jones RG, and Lien EC
- Abstract
Cancer cells are exposed to diverse metabolites in the tumor microenvironment that are used to support the synthesis of nucleotides, amino acids, and lipids needed for rapid cell proliferation
1-3 . Recent work has shown that ketone bodies such as β-hydroxybutyrate (β-OHB), which are elevated in circulation under fasting conditions or low glycemic diets, can serve as an alternative fuel that is metabolized in the mitochondria to provide acetyl-CoA for the tricarboxylic acid (TCA) cycle in some tumors4-7 . Here, we discover a non-canonical route for β-OHB metabolism, in which β-OHB can bypass the TCA cycle to generate cytosolic acetyl-CoA for de novo fatty acid synthesis in cancer cells. We show that β-OHB-derived acetoacetate in the mitochondria can be shunted into the cytosol, where acetoacetyl-CoA synthetase (AACS) and thiolase convert it into acetyl-CoA for fatty acid synthesis. This alternative metabolic routing of β-OHB allows it to avoid oxidation in the mitochondria and net contribute to anabolic biosynthetic processes. In cancer cells, β-OHB is used for fatty acid synthesis to support cell proliferation under lipid-limited conditions in vitro and contributes to tumor growth under lipid-limited conditions induced by a calorie-restricted diet in vivo . Together, these data demonstrate that β-OHB is preferentially used for fatty acid synthesis in cancer cells to support tumor growth., Competing Interests: Competing interests: R.G.J. is a scientific advisor to Servier Pharmaceuticals and is a member of the Scientific Advisory Board of Immunomet Therapeutics. All other authors declare no competing interests.- Published
- 2024
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5. Glucose-dependent glycosphingolipid biosynthesis fuels CD8 + T cell function and tumor control.
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Longo J, DeCamp LM, Oswald BM, Teis R, Reyes-Oliveras A, Dahabieh MS, Ellis AE, Vincent MP, Damico H, Gallik KL, Compton SE, Capan CD, Williams KS, Esquibel CR, Madaj ZB, Lee H, Roy DG, Krawczyk CM, Haab BB, Sheldon RD, and Jones RG
- Abstract
Glucose is essential for T cell proliferation and function, yet its specific metabolic roles in vivo remain poorly defined. Here, we identify glycosphingolipid (GSL) biosynthesis as a key pathway fueled by glucose that enables CD8
+ T cell expansion and cytotoxic function in vivo . Using13 C-based stable isotope tracing, we demonstrate that CD8+ effector T cells use glucose to synthesize uridine diphosphate-glucose (UDP-Glc), a precursor for glycogen, glycan, and GSL biosynthesis. Inhibiting GSL production by targeting the enzymes UGP2 or UGCG impairs CD8+ T cell expansion and cytolytic activity without affecting glucose-dependent energy production. Mechanistically, we show that glucose-dependent GSL biosynthesis is required for plasma membrane lipid raft integrity and aggregation following TCR stimulation. Moreover, UGCG-deficient CD8+ T cells display reduced granzyme expression and tumor control in vivo . Together, our data establish GSL biosynthesis as a critical metabolic fate of glucose-independent of energy production-required for CD8+ T cell responses in vivo ., Competing Interests: DECLARATION OF INTERESTS R.G.J. is a scientific advisor to Servier Pharmaceuticals and is a member of the Scientific Advisory Board of Immunomet Therapeutics.- Published
- 2024
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6. Global Workforce and Access: Demand, Education, Quality.
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Grover S, Court L, Amoo-Mitchual S, Longo J, Rodin D, Scott AA, Lievens Y, Yap ML, Abdel-Wahab M, Lee P, Harsdorf E, Khader J, Jia X, Dosanjh M, Elzawawy A, Ige T, Pomper M, Pistenmaa D, Hardenbergh P, Petereit DG, Sargent M, Cina K, Li B, Anacak Y, Mayo C, Prattipati S, Lasebikan N, Rendle K, O'Brien D, Wendling E, and Coleman CN
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- Humans, Global Health, Developing Countries, Healthcare Disparities, Health Services Needs and Demand, Health Services Accessibility, Radiation Oncology, Neoplasms radiotherapy
- Abstract
There has long existed a substantial disparity in access to radiotherapy globally. This issue has only been exacerbated as the growing disparity of cancer incidence between high-income countries (HIC) and low and middle-income countries (LMICs) widens, with a pronounced increase in cancer cases in LMICs. Even within HICs, iniquities within local communities may lead to a lack of access to care. Due to these trends, it is imperative to find solutions to narrow global disparities. This requires the engagement of a diverse cohort of stakeholders, including working professionals, non-governmental organizations, nonprofits, professional societies, academic and training institutions, and industry. This review brings together a diverse group of experts to highlight critical areas that could help reduce the current global disparities in radiation oncology. Advancements in technology and treatment, such as artificial intelligence, brachytherapy, hypofractionation, and digital networks, in combination with implementation science and novel funding mechanisms, offer means for increasing access to care and education globally. Common themes across sections reveal how utilizing these new innovations and strengthening collaborative efforts among stakeholders can help improve access to care globally while setting the framework for the next generation of innovations., (Copyright © 2024 Elsevier Inc. All rights reserved.)
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- 2024
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7. Sarcopenia is associated with survival in patients awaiting kidney transplant.
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Wendland J, Seth A, Ten Eyck P, Longo J, Binns G, Sanders ML, Hornickel JL, Swee M, Kalil R, and Katz DA
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Background: The relationship of sarcopenia to frailty and other survival determinants in patients waitlisted for kidney transplant is not well characterized. Our goal was to evaluate the relationship of muscle area to functional and frailty metrics and its impact on survival in patients waitlisted for kidney transplant., Methods: Among 303 consecutively listed transplant candidates, 172 had a computed scan within 3 months of frailty and biochemical testing that permitted muscle area evaluation. Third lumbar level psoas muscle indices (total bilateral psoas area/height
2 ) were calculated. Testing included frailty metrics, treadmill and pedometer ability, troponin, and brain natriuretic peptide levels. Associations between muscle area, demographic, biochemical, and frailty measures were analyzed. Log-rank test was used to evaluate waitlist survival on the basis of muscle area, and multivariate Cox proportional hazards modeling was used to evaluate factors independently associated with survival., Results: Demographic factors associated with third lumbar level psoas muscle indices include male sex (P < .001), race (P = .02), age (P = .004), and body mass index (P < .0001). Grip strength, treadmill ability, and Sit-Stands positively correlated with third lumbar level psoas muscle indices (P < .01). Brain natriuretic peptide and Up and Go negatively correlated with third lumbar level psoas muscle indices (P < .01). Survival was significantly associated with third lumbar level psoas muscle indices (P = 0.02). Treadmill ability, Sit-Stands, Up and Go, race and muscle area were most closely associated with waitlist survival on multivariate modeling., Conclusion: Sarcopenia as assessed with muscle area measurements is independently associated with kidney waitlist survival. Functional ability and muscle area may be overlapping, but noncongruent, determinants of waitlist outcomes and may need to be individually assessed to create the most predictive survival model., Competing Interests: Conflict of Interest/Disclosure Dr Katz reports commercial research support for immunosuppression drug trials from Bristol Myers Squibb and participation in the Hansa Biopharma ConfideS imlifidase trial in highly sensitized transplant candidates. Dr Kalil reports a research grant from Eurofins. All other authors declare no potential conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)- Published
- 2024
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8. Statin Concentration in Prostatic Tissue is Subtype- and Dose-dependent.
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Chavarriaga J, Penn LZ, Khurram N, Lajkosz K, Longo J, Chen E, Fleshner N, van der Kwast T, and Hamilton RJ
- Abstract
Objective: To evaluate for the first time, comparative serum and prostate tissue concentrations of lipophilic and hydrophilic statins., Methods: After reviewing all patients who underwent radical prostatectomy between 1993 and 2019, we selected 80 patients taking atorvastatin (lipophilic) or rosuvastatin (hydrophilic) for cholesterol control and with available banked fresh-frozen tissue from the prostatectomy. Primary endpoint was serum and prostate statin concentration measured by HPLC-mass spectrometry analysis. Serum/prostate statin concentrations were compared between patients on atorvastatin and rosuvastatin, and patients receiving high- and low-dose statin, using the Mann-Whitney U test., Results: In total, 39 patients were taking atorvastatin and 41 were taking rosuvastatin. Thirty-eight and 42 were taking high- and low-dose statin, respectively. Statin concentration was measurable in the prostatic tissue of 15 patients (38.4%) taking atorvastatin (33.3% high-dose vs 42.8% low-dose) compared to 22 (53.6%) taking rosuvastatin (55% high-dose vs 52.3% low-dose). Median tissue concentration of rosuvastatin was greater than atorvastatin (3.98 ng/g vs 0.96 ng/g, P <.001). Dose-dependency was observed: median prostate concentration was higher in those taking high-dose versus low-dose statin for both atorvastatin (1.22 ng/g vs 0.79 ng/g, P = .69) and rosuvastatin (5.21 ng/g vs 1.99 ng/g, P <.001)., Conclusion: We have shown, for the first time, that lipophilic and hydrophilic statins can be measured in the prostate of patients with prostate cancer and that the concentrations are dependent on dose. Moreover, rosuvastatin, a hydrophilic statin, achieves a 4-fold higher concentration in the prostate., 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 © 2024 Elsevier Inc. All rights reserved.)
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- 2024
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9. NRF2-dependent regulation of the prostacyclin receptor PTGIR drives CD8 T cell exhaustion.
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Dahabieh MS, DeCamp LM, Oswald BM, Kitchen-Goosen SM, Fu Z, Vos M, Compton SE, Longo J, Williams KS, Ellis AE, Johnson A, Sodiya I, Vincent M, Lee H, Sheldon RD, Krawczyk CM, Yao C, Wu T, and Jones RG
- Abstract
The progressive decline of CD8 T cell effector function-also known as terminal exhaustion-is a major contributor to immune evasion in cancer. Yet, the molecular mechanisms that drive CD8 T cell dysfunction remain poorly understood. Here, we report that the Kelch-like ECH-associated protein 1 (KEAP1)-Nuclear factor erythroid 2-related factor 2 (NRF2) signaling axis, which mediates cellular adaptations to oxidative stress, directly regulates CD8 T cell exhaustion. Transcriptional profiling of dysfunctional CD8 T cells from chronic infection and cancer reveals enrichment of NRF2 activity in terminally exhausted (Tex
term ) CD8 T cells. Increasing NRF2 activity in CD8 T cells (via conditional deletion of KEAP1) promotes increased glutathione production and antioxidant defense yet accelerates the development of terminally exhausted (PD-1+ TIM-3+ ) CD8 T cells in response to chronic infection or tumor challenge. Mechanistically, we identify PTGIR, a receptor for the circulating eicosanoid prostacyclin, as an NRF2-regulated protein that promotes CD8 T cell dysfunction. Silencing PTGIR expression restores the anti-tumor function of KEAP1-deficient T cells. Moreover, lowering PTGIR expression in CD8 T cells both reduces terminal exhaustion and enhances T cell effector responses (i.e. IFN-γ and granzyme production) to chronic infection and cancer. Together, these results establish the KEAP1-NRF2 axis as a metabolic sensor linking oxidative stress to CD8 T cell dysfunction and identify the prostacyclin receptor PTGIR as an NRF2-regulated immune checkpoint that regulates CD8 T cell fate decisions between effector and exhausted states., Competing Interests: Competing interests: RGJ is a scientific advisor for Servier Pharmaceuticals and is a member of the Scientific Advisory Board of Immunomet Therapeutics.- Published
- 2024
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10. 13 C metabolite tracing reveals glutamine and acetate as critical in vivo fuels for CD8 T cells.
- Author
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Ma EH, Dahabieh MS, DeCamp LM, Kaymak I, Kitchen-Goosen SM, Oswald BM, Longo J, Roy DG, Verway MJ, Johnson RM, Samborska B, Duimstra LR, Scullion CA, Steadman M, Vos M, Roddy TP, Krawczyk CM, Williams KS, Sheldon RD, and Jones RG
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- Animals, Mice, Listeriosis metabolism, Listeriosis immunology, Listeriosis microbiology, Listeria monocytogenes, Citric Acid Cycle, Glucose metabolism, Mice, Inbred C57BL, Glutamine metabolism, CD8-Positive T-Lymphocytes metabolism, Acetates metabolism, Carbon Isotopes
- Abstract
Infusion of
13 C-labeled metabolites provides a gold standard for understanding the metabolic processes used by T cells during immune responses in vivo. Through infusion of13 C-labeled metabolites (glucose, glutamine, and acetate) in Listeria monocytogenes -infected mice, we demonstrate that CD8 T effector (Teff) cells use metabolites for specific pathways during specific phases of activation. Highly proliferative early Teff cells in vivo shunt glucose primarily toward nucleotide synthesis and leverage glutamine anaplerosis in the tricarboxylic acid (TCA) cycle to support adenosine triphosphate and de novo pyrimidine synthesis. In addition, early Teff cells rely on glutamic-oxaloacetic transaminase 1 (Got1)-which regulates de novo aspartate synthesis-for effector cell expansion in vivo. CD8 Teff cells change fuel preference over the course of infection, switching from glutamine- to acetate-dependent TCA cycle metabolism late in infection. This study provides insights into the dynamics of Teff metabolism, illuminating distinct pathways of fuel consumption associated with CD8 Teff cell function in vivo.- Published
- 2024
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11. Identifying, Diagnosing, and Grading Malignant Peripheral Nerve Sheath Tumors in Genetically Engineered Mouse Models.
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Jenkins DP, Turner-Ivey B, Fromm Longo J, and Carroll SL
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- Animals, Mice, Neoplasm Grading, Humans, Mice, Transgenic, Disease Models, Animal, Nerve Sheath Neoplasms genetics, Nerve Sheath Neoplasms pathology
- Abstract
Patients with the autosomal dominant tumor susceptibility syndrome neurofibromatosis type 1 (NF1) commonly develop plexiform neurofibromas (PNs) that subsequently transform into highly aggressive malignant peripheral nerve sheath tumors (MPNSTs). Understanding the process by which a PN transforms into an MPNST would be facilitated by the availability of genetically engineered mouse (GEM) models that accurately replicate the PN-MPNST progression seen in humans with NF1. Unfortunately, GEM models with Nf1 ablation do not fully recapitulate this process. This led us to develop P0-GGFβ3 mice, a GEM model in which overexpression of the Schwann cell mitogen neuregulin-1 (NRG1) in Schwann cells results in the development of PNs that progress to become MPNSTs with high frequency. However, to determine whether tumorigenesis and neoplastic progression in P0-GGFβ3 mice accurately model the processes seen in NF1 patients, we had to first prove that the pathology of P0-GGFβ3 peripheral nerve sheath tumors recapitulates the pathology of their human counterparts. Here, we describe the specialized methodologies used to accurately diagnose and grade peripheral nervous system neoplasms in GEM models, using P0-GGFβ3 and P0-GGFβ3;Trp53
+/- mice as an example. We describe the histologic, immunohistochemical, and histochemical methods used to diagnose PNs and MPNSTs, how to distinguish these neoplasms from other tumor types that mimic their pathology, and how to grade these neoplasms. We discuss the establishment of early-passage cultures from GEM MPNSTs, how to characterize these cultures using immunocytochemistry, and how to verify their tumorigenicity by establishing allografts. Collectively, these techniques characterize the pathology of PNs and MPNSTs that arise in GEM models and critically compare the pathology of these murine tumors to their human counterparts.- Published
- 2024
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12. Evaluating possible maternal effect lethality and genetic background effects in Naa10 knockout mice.
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Lyon GJ, Longo J, Garcia A, Inusa F, Marchi E, Shi D, Dörfel M, Arnesen T, Aldabe R, Lyons S, Nashat MA, and Bolton D
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- Animals, Mice, Female, Male, Phenotype, Genetic Background, Maternal Inheritance genetics, Mice, Inbred C57BL, N-Terminal Acetyltransferase A genetics, N-Terminal Acetyltransferase A metabolism, N-Terminal Acetyltransferase E genetics, N-Terminal Acetyltransferase E metabolism, Mice, Knockout
- Abstract
Amino-terminal (Nt-) acetylation (NTA) is a common protein modification, affecting approximately 80% of all human proteins. The human essential X-linked gene, NAA10, encodes for the enzyme NAA10, which is the catalytic subunit in the N-terminal acetyltransferase A (NatA) complex. There is extensive genetic variation in humans with missense, splice-site, and C-terminal frameshift variants in NAA10. In mice, Naa10 is not an essential gene, as there exists a paralogous gene, Naa12, that substantially rescues Naa10 knockout mice from embryonic lethality, whereas double knockouts (Naa10-/Y Naa12-/-) are embryonic lethal. However, the phenotypic variability in the mice is nonetheless quite extensive, including piebaldism, skeletal defects, small size, hydrocephaly, hydronephrosis, and neonatal lethality. Here we replicate these phenotypes with new genetic alleles in mice, but we demonstrate their modulation by genetic background and environmental effects. We cannot replicate a prior report of "maternal effect lethality" for heterozygous Naa10-/X female mice, but we do observe a small amount of embryonic lethality in the Naa10-/y male mice on the inbred genetic background in this different animal facility., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Lyon et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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13. Acod1 expression in cancer cells promotes immune evasion through the generation of inhibitory peptides.
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Schofield JH, Longo J, Sheldon RD, Albano E, Ellis AE, Hawk MA, Murphy S, Duong L, Rahmy S, Lu X, Jones RG, and Schafer ZT
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- Humans, Animals, Cell Line, Tumor, Mice, CD8-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes metabolism, Peptides metabolism, Peptides pharmacology, Neoplasms immunology, Neoplasms pathology, Neoplasms metabolism, Neoplasms drug therapy, Cell Proliferation drug effects, Immune Evasion, Mice, Inbred C57BL, Carboxy-Lyases metabolism
- Abstract
Targeting programmed cell death protein 1 (PD-1) is an important component of many immune checkpoint blockade (ICB) therapeutic approaches. However, ICB is not an efficacious strategy in a variety of cancer types, in part due to immunosuppressive metabolites in the tumor microenvironment. Here, we find that αPD-1-resistant cancer cells produce abundant itaconate (ITA) due to enhanced levels of aconitate decarboxylase (Acod1). Acod1 has an important role in the resistance to αPD-1, as decreasing Acod1 levels in αPD-1-resistant cancer cells can sensitize tumors to αPD-1 therapy. Mechanistically, cancer cells with high Acod1 inhibit the proliferation of naive CD8
+ T cells through the secretion of inhibitory factors. Surprisingly, inhibition of CD8+ T cell proliferation is not dependent on the secretion of ITA but is instead a consequence of the release of small inhibitory peptides. Our study suggests that strategies to counter the activity of Acod1 in cancer cells may sensitize tumors to ICB therapy., Competing Interests: Declaration of interests R.G.J. is a scientific advisor for Agios Pharmaceuticals and Servier Pharmaceuticals and is a member of the scientific advisory board of ImmunoMet Therapeutics., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)- Published
- 2024
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14. The Uncertainty in Family Caregivers of Hospitalized Persons With a Stroke in Saudi Arabia: Unitary Caring Perspective.
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Alselami S, Butcher HK, and Longo J
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- Humans, Saudi Arabia, Uncertainty, Family, Qualitative Research, Caregivers, Stroke therapy
- Abstract
Uncertainty is a universal experience of family caregivers caring for persons with a stroke and affects caregivers' readiness to care for their family members with a stroke. Guided by the unitary caring theory and unitary-caring hermeneutic-phenomenological research method, this study was conducted among 15 family caregivers of persons in the hospital who have survived strokes through in-depth semi-structured interviews. Five essences emerged from the analysis: living in a dark reality; yearning for professional support; enduring a life full of tribulations; attempting resolution; and creating new patterns of living. Each of the 5 essences was interpreted from Smith's unitary caring theory perspective., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2024
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