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Sok, S.

Publications and source records attributed to Sok, S..

3 recordsLinked to original sources

OPA1-dependent mitochondrial remodeling coordinates TCR signaling and metabolic adaptation during iNKT cell differentiation

Invariant natural killer T (iNKT) cells require mitochondrial metabolism for terminal effector development. We found iNKT cells express elevated levels of proteins regulating mitochondrial membrane dynamics, and identified Opa1, but not Drp1, as selectively required for iNKT cell differentiation. OPA1 deficiency disrupted mitochondrial cristae organization, reduced mitochondrial membrane potential, increased mitochondrial mass, and altered calcium homeostasis in iNKT cells. Bulk and single-cell transcriptomic analyses revealed impaired TCR-responsive gene expression, activation of mitochondrial stress adaptation and integrated stress response, enhanced glycolysis, and retention of immature differentiation features. SCENITH analysis demonstrated increased glycolytic dependence; LDHA became required in Opa1-deficient iNKT cells while dispensable for normal iNKT development, indicating compensatory glycolytic adaptation. EGTA in thymic organ culture partially restored NKT1 marker expression in Opa1-deficient cells. Co-deletion of Drp1 improved mitochondrial morphology, TCR signaling, stress and metabolic adaptation, and partially rescued iNKT cell differentiation, demonstrating that balanced mitochondrial dynamics coordinate mitochondrial function and terminal effector development.

immunology↗

Health behaviors among male and female university students in Cambodia: a cross-sectional survey

BackgroundStudents go through a transition when they enter university, which involves major individual and contextual changes in every domain of life that may lead to several behavioral and health problems. This paper describes a wide range of health behaviors among male and female university students in Cambodia.\n\nMethodsA cross-sectional survey was conducted in 2015 among students randomly selected from the Royal University of Phnom Penh and University of Battambang. Health-related behaviors in different domains were collected using a structured questionnaire. Chi-square test, Fishers exact test, or independent Students t-test was used as appropriate to describe and compare the variables among male and female students.\n\nResultsThis study included 1359 students, of whom 50.8% were male, and the mean age was 21.3 years (SD= 2.3). Of the total, 79.5% reported not having any vigorous-intensity activities, 25.9% not having moderate-intensity activities, and 33.5% not having walked continuously for 10 minutes during the past seven days. The prevalence of substance use was low with 38.3% currently drinking alcohol, 1.1% smoking tobacco, and 0.4% using an illicit drug during the past 12 months. About one in ten (10.6%) reported having sexual intercourse, with a mean number of partners of 2.1 (SD= 2.4) during the past 12 months, and 42.4% not using a condom in the last intercourse. Only 7.1% reported having been diagnosed with a sexually transmitted infection in the past 12 months; of whom, 60% sought for treatment. About one-third (33.6%) reported eating fast food once or twice, and 5.3% having it three times or more over the last week. More than half (55.6%) had one to two servings of fruits and vegetables daily, and 9.9% did not eat any fruits and vegetables over the last week.\n\nConclusionsWe found that the prevalence of sexual risk behaviors and substance use was plausibly low among university students in this study. However, the rates of inactive lifestyle and unhealthy food consumption were concerning. Public policy and universities should promote healthy behaviors among the students. The interventions may take advantage of and expend upon the good health behaviors and consider gender differences.

scientific communication and education↗

Acceptability of active case finding with a seed-and-recruit model to improve tuberculosis case detection and linkage to treatment in Cambodia: a qualitative study

BackgroundWith support of the national tuberculosis (TB) program, KHANA has implemented an innovative approach using a seed-and-recruit model to actively find TB cases in the community. The intervention engaged community members including TB survivors to recruit people with TB symptoms in a snowball approach for screening and linkage to treatment. This study aims to explore the acceptability of active case finding with the seed-and-recruit model in detecting new TB cases and determine the characteristics of successful seeds.\n\nMethodsThis qualitative study was conducted in four provinces (Banteay Meanchey, Kampong Chhnang, Siem Reap, and Takeo) in Cambodia in 2017. Fifty six in-depth interviews and ten focus group discussions were conducted to gain insights into the acceptability, strengths, and challenges in implementing the model. Transcripts were coded and content analyses were performed.\n\nResultsThe seed-and-recruit active case finding model was generally well-received by the study participants. They saw the benefits of engaging TB survivors and utilize their social network to find new TB cases in the community. The social embeddedness of the model within the local community was one of the major strengths. The success of the model also hinges on the integration with existing health facilities. Having extensive social network, being motivated, and having good knowledge about TB were important characteristics of successful seeds. Study participants reported challenges in motivating the recruits for screening, logistic capacities, and high workload during implementation. However, there was a general consensus that the model ought to be expanded.\n\nConclusionsThese findings indicate that the seed-and-recruit model should be fine-tuned and scaled up as part of the national TB Program to increase TB new case detection in Cambodia. Further studies are needed to more comprehensively evaluate the impacts and cost-effectiveness of the model in Cambodia as well as in other resource-limited settings.

epidemiology↗