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Background Estimates of the relative contribution of different pathogens to all-cause diarrhoea mortality are needed to inform global diarrhoea burden models and prioritize interventions. We aimed to investigate and estimate heterogeneity in the case fatality risk (CFR) of different diarrhoeal pathogens. Methods We conducted a systematic review and meta-analysis of studies that reported cases and deaths for 15 enteric pathogens published between 1990 and 2019. The primary outcome was the pathogen-specific CFR stratified by age group, country-specific under-5 mortality rate, setting, study year and rotavirus vaccine introduction status. We developed fixed-effects and multilevel mixed-effects logistic regression models to estimate the pooled CFR overall and for each pathogen, controlling for potential predictors of heterogeneity. Results A total of 416 studies met review criteria and were included in the analysis. The overall crude CFR for all pathogens was 0.65%, but there was considerable heterogeneity between and within studies. The overall CFR estimated from a random-effects model was 0.04% (95% CI: 0.026%–0.062%), whereas the pathogen-specific CFR estimates ranged from 0% to 2.7%. When pathogens were included as predictors of the CFR in the overall model, the highest and lowest odds ratios were found for enteropathogenic Escherichia coli (EPEC) [odds ratio (OR) = 3.0, 95% CI: 1.28–7.07] and rotavirus (OR = 0.23, 95% CI: 0.13–0.39), respectively. Conclusion We provide comprehensive estimates of the CFR across different diarrhoeal pathogens and highlight pathogens for which more studies are needed. The results motivate the need for diarrhoeal interventions and could help prioritize pathogens for vaccine development.

Background An aim of this study is to introduce a practitioner-friendly behavior model. Few theories of health behavior explicitly take the effect of social norms on behavior into account. Generally, theories that do take social norms into account assume that the effect of social norms on behavior operates through motivation. We use the Fogg Behavior Model (FBM), a behavior model that is new to public health, to explore whether social norms are associated with modern contraceptive use among Nigerian women, and whether they affect behavior through motivation or through ability. In other words, do social norms that discourage contraception lower women’s motivation to use contraception or do they lower women’s ability to use contraception. Methods This study uses data from a cross-sectional household survey of Nigerian women, ages 14–24. The survey collected data on socio-economic and demographic characteristics of women, whether they were sexually experienced, and whether they used contraception. Modern contraceptive use was the outcome of interest for the study. The survey also collected data on social norms around premarital sex and contraceptive use. Multivariate logistic regression was used for the analysis. Results After adjusting for a range of socio-economic and demographic variables, we found that social norms that discourage contraception had a statistically significant negative association with contraceptive use (aOR = 0.90, p Conclusion These findings suggest that social norms may affect contraceptive use in Nigeria through ability rather than motivation. In terms of programmatic implications, these finding suggest that public health interventions may be able to counter the negative effects of social norms that discourage contraceptive use by increasing women’s ability to practice contraception.

Background: Asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) represents the confluence of bronchial airway hyperreactivity and chronic airflow limitation and has been described as leading to worse lung function and quality of life than found with either singular disease process. Objective: We aimed to describe the prevalence and risk factors for ACO among adults across 6 low- and middle-income countries (LMICs). Methods: We compiled cross-sectional data for 11,923 participants aged 35 to 92 years from 4 population-based studies in 12 settings. We defined COPD as postbronchodilator FEV 1 /forced vital capacity ratio below the lower limit of normal, asthma as wheeze or medication use in 12 months or self-reported physician diagnosis, and ACO as having both. Results: The prevalence of ACO was 3.8% (0% in rural Puno, Peru, to 7.8% in Matlab, Bangladesh). The odds of having ACO were higher with household exposure to biomass fuel smoke (odds ratio [OR], 1.48; 95% CI, 0.98-2.23), smoking tobacco (OR, 1.28 per 10 pack-years; 95% CI, 1.22-1.34), and having primary or less education (OR, 1.35; 95% CI, 1.07-1.70) as compared to nonobstructed nonasthma individuals. ACO was associated with severe obstruction (FEV 1 %

Additional file 1. Supplementary information.

Background Non-communicable diseases (NCDs) are an increasing global concern, with morbidity and mortality largely occurring in low- and middle-income settings. We established the prospective Rural Uganda Non-Communicable Disease (RUNCD) cohort to longitudinally characterize the NCD prevalence, progression, and complications in rural Africa. Methods We conducted a population-based census for NCD research. We systematically enrolled adults in each household among three sub-counties of the larger Nakaseke Health district and collected baseline demographic, health status, and self-reported chronic disease information. We present our data on self-reported chronic disease, as stratified by age, sex, educational attainment, and sub-county. Results A total of 16,694 adults were surveyed with 10,563 (63%) respondents enrolled in the self-reported study. Average age was 37.8 years (SD = 16.5) and 45% (7481) were male. Among self-reported diseases, hypertension (HTN) was most prevalent (6.3%). 1.1% of participants reported a diagnosis of diabetes, 1.1% asthma, 0.7% COPD, and 0.4% kidney disease. 2.4% of the population described more than one NCD. Self-reported HTN was significantly higher in the peri-urban subcounty than in the other two rural sub-counties (p Conclusions The RUNCD will establish one of the largest NCD patient cohorts in rural Africa. First analysis highlights the feasibility of systematically enrolling large numbers of adults living in a rural Ugandan district. In addition, our study demonstrates low levels of self-reported NCDs compared to the nation-wide established levels, emphasizing the need to better educate, characterize, and care for the majority of rural communities.

Background: Few theories of health behavior explicitly take the effect of social norms on behavior into account. The ones that do assume that the effect of norms on behavior operates through motivation. We use a behavior model that is new to public health to test whether norms affect behavior through motivation or ability. Methods: This study uses data from a household survey of Nigerian women, ages 14-24. The survey collected data on socio-economic and demographic characteristics of women, whether they were sexually experienced, and whether they used contraception. The survey also collected data on descriptive and injunctive norms around premarital sex and contraceptive use. Multivariate logistic regression was used to test whether the effect of unfavorable social norms on modern contraceptive use operates through motivation or ability. Results: The data was used to construct variables measuring unfavorable social norms, motivation, ability, and modern contraceptive use. After adjusting for a range of socio-economic and demographic variables, we found that unfavorable social norms had a statistically significant negative effect on contraceptive use. The analysis suggests that the effect of unfavorable social norms on contraceptive use operates through ability.Conclusion: This study sheds light on the pathway through which social norms affect contraceptive use. The findings suggest that public health interventions may be able to counter the negative effects of unfavorable social norms on modern contraceptive use by increasing women’s ability to practice contraception. These findings have important implications for the design of interventions that aim to increase contraceptive use among young women in Nigeria. The study also demonstrates the utility of the FBM, a practitioner-friendly, behavior change model, in examining the relationship between norms and behavior.

BackgroundWhile head circumference (HC) has been related to intracranial volume and brain size, its association with cognitive function remains unclear. We sought to understand the relationship among various biological and socioeconomic risk factors, HC and cognitive development.MethodsWe analysed data across resource-poor settings in Bangladesh, India, Nepal, Peru, South Africa and Tanzania from the Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development longitudinal birth cohort study. Participating children were enrolled and followed up between 2009 and 2014. A final sample of 1210 children aged 0–24 months were included in the analyses. The main outcomes were HC for age Z-score and cognitive, gross motor and language scores from Bayley Scales of Infant Development-III tests. Length, weight and HC were measured monthly, and cognitive tests were administered at 6, 15 and 24 months of age. To disentangle the associations between risk factors and HC from linear growth and to distinguish the direct and indirect effects of these risk factors on cognitive function, we conducted mediation analysis using longitudinal models to account for all data measured during follow-up.ResultsAverage HC-for-age Z-score (HCAZ) was −0.54 (95% CI −0.47 to −0.62) near birth and −1.01 (95% CI −0.94 to −1.08) at 24 months. Children with higher enrolment weight (pConclusionsThe main risk factors associated with HC are similar to those associated with body length, and HC is not related to cognitive function.

OBJECTIVES: To determine the association between mean airway pressure and 90-day mortality in patients with acute respiratory failure requiring mechanical ventilation and to compare the predictive ability of mean airway pressure compared with inspiratory plateau pressure and driving pressure. DESIGN: Prospective observational cohort. SETTING: Five ICUs in Lima, Peru. SUBJECTS: Adults requiring invasive mechanical ventilation via endotracheal tube for acute respiratory failure. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of potentially eligible participants (n = 1,500), 65 (4%) were missing baseline mean airway pressure, while 352 (23.5%) were missing baseline plateau pressure and driving pressure. Ultimately, 1,429 participants were included in the analysis with an average age of 59 ± 19 years, 45% female, and a mean Pao(2)/Fio(2) ratio of 248 ± 147 mm Hg at baseline. Overall, 90-day mortality was 50.4%. Median baseline mean airway pressure was 13 cm H(2)O (interquartile range, 10–16 cm H(2)O) in participants who died compared to a median mean airway pressure of 12 cm H(2)O (interquartile range, 10–14 cm H(2)O) in participants who survived greater than 90 days (p < 0.001). Mean airway pressure was independently associated with 90-day mortality (odds ratio, 1.38 for difference comparing the 75th to the 25th percentile for mean airway pressure; 95% CI, 1.10–1.74) after adjusting for age, sex, baseline Acute Physiology and Chronic Health Evaluation III, baseline Pao(2)/Fio(2) (modeled with restricted cubic spline), baseline positive end-expiratory pressure, baseline tidal volume, and hospital site. In predicting 90-day mortality, baseline mean airway pressure demonstrated similar discriminative ability (adjusted area under the curve = 0.69) and calibration characteristics as baseline plateau pressure and driving pressure. CONCLUSIONS: In a multicenter prospective cohort, baseline mean airway pressure was independently associated with 90-day mortality in mechanically ventilated participants and predicts mortality similarly to plateau pressure and driving pressure. Because mean airway pressure is readily available on all mechanically ventilated patients and all ventilator modes, it is a potentially more useful predictor of mortality in acute respiratory failure.

To determine the prevalence of chronic respiratory diseases in urban and rural Uganda and to identify risk factors for these diseases.The population-based, cross-sectional study included adults aged 35 years or older. All participants were evaluated by spirometry according to standard guidelines and completed questionnaires on respiratory symptoms, functional status and demographic characteristics. The presence of four chronic respiratory conditions was monitored: chronic obstructive pulmonary disease (COPD), asthma, chronic bronchitis and a restrictive spirometry pattern.In total, 1502 participants (average age: 46.9 years) had acceptable, reproducible spirometry results: 837 (56%) in rural Nakaseke and 665 (44%) in urban Kampala. Overall, 46.5% (698/1502) were male. The age-adjusted prevalence of any chronic respiratory condition was 20.2%. The age-adjusted prevalence of COPD was significantly greater in rural than urban participants (6.1 versus 1.5%, respectively;The prevalence of chronic respiratory disease was high in both rural and urban Uganda. Place of residence was the most important risk factor for COPD and asthma.Déterminer la prévalence de maladies respiratoires chroniques en zones urbaines et rurales en Ouganda et identifier les facteurs de risque associés à ces maladies.L'étude de prévalence basée sur une population incluait des adultes âgés de 35 ans ou plus. Tous les participants ont été soumis à un test de spirométrie conformément aux directives standards et ont rempli un questionnaire sur leurs symptômes respiratoires, leur état fonctionnel et leurs caractéristiques démographiques. La présence de quatre maladies respiratoires chroniques a été contrôlée: bronchopneumopathie chronique obstructive, asthme, bronchite chronique et modèle de spirométrie restrictive.Au total, 1502 individus (âge moyen: 46,9 ans) ont obtenu des résultats de spirométrie acceptables, reproductibles: 837 (56%) à Nakaseke, en zone rurale, et 665 (44%) à Kampala, en zone urbaine. Dans l'ensemble, 46,5% (698/1502) étaient des hommes. La prévalence ajustée selon l'âge de toutes les maladies respiratoires chroniques était de 20,2%. La prévalence ajustée selon l'âge de la bronchopneumopathie chronique obstructive était considérablement plus élevée chez les participants ruraux que chez les participants urbains (6,1 contre 1,5%, respectivement;La prévalence de maladies respiratoires chroniques était élevée à la fois en zone rurale et en zone urbaine en Ouganda. Le lieu de résidence était le facteur de risque le plus important pour la bronchopneumopathie chronique obstructive et l'asthme.Determinar la prevalencia de las enfermedades respiratorias crónicas en las zonas urbanas y rurales de Uganda e identificar los factores de riesgo de estas.El estudio transversal basado en la población incluyó adultos de 35 años o más. Todos los participantes se evaluaron por espirometría de acuerdo con las directrices estándar y completaron cuestionarios sobre los síntomas respiratorios, el estado funcional y las características demográficas. Se monitorizó la presencia de cuatro afecciones respiratorias crónicas: enfermedad pulmonar obstructiva crónica (EPOC), asma, bronquitis crónica y un patrón de espirometría restrictivo.En total, 1502 participantes (edad media: 46,9 años) tuvieron unos resultados de espirometría aceptables y reproducibles: 837 (56 %) en la zona rural de Nakaseke y 665 (44 %) en la zona urbana de Kampala. En total, el 46,5 % (698/1502) eran hombres. La prevalencia ajustada por edad de cualquier afección respiratoria crónica fue de 20,2 %. La prevalencia de la EPOC ajustada por edad fue significativamente mayor en los participantes rurales que en los urbanos (6,1 frente a 1,5 %, respectivamente; p0,001), mientras que el asma fue significativamente más frecuente en los participantes urbanos: 9,7 % frente a 4,4 % en los participantes rurales (p0,001). La prevalencia ajustada por edad de la bronquitis crónica fue similar en los participantes rurales y urbanos (3,5 % frente a 2,2 %, respectivamente; p = 0,62), al igual que la de un patrón espirométrico restrictivo (10,9 % frente a 9,4 %; p = 0,82). Para la EPOC, el riesgo atribuible a la población fue del 51,5 % para la residencia rural, del 19,5 % para el tabaco, del 16,0 % para un índice de masa corporal inferior a 18,5 kg/mLa prevalencia de las enfermedades respiratorias crónicas era alta tanto en las zonas rurales como en las urbanas de Uganda. El lugar de residencia fue el factor de riesgo más importante para la EPOC y el asma.تحديد مدى انتشار أمراض الجهاز التنفسي المزمنة في المناطق الحضرية والريفية في أوغندا، وتحديد عوامل الخطر لهذه الأمراض.دراسة لقطاعات سكانية متعددة شملت الكبار ممن يبلغون 35 عاماً أو أكبر. تم تقييم جميع المشاركين عن طريق قياس التنفس وفقا للمبادئ التوجيهية القياسية والاستبيانات المكتملة على أعراض الجهاز التنفسي، والحالة الوظيفية، والخصائص الديموغرافية. تم رصد وجود أربع حالات تنفسية مزمنة: مرض الانسداد الرئوي المزمن (COPD)، والربو، والتهاب الشعب الهوائية المزمن، ونمط قياس التنفس المقيد.إجمالاً، كان لدى 1502 مشاركًا (متوسط العمر: 46.9 عامًا) نتائج قياس تنفس مقبولة ومتكررة: 837 (56٪) في منطقة ناكاسيكي الريفية و665 (44٪) في كامبالا الحضرية. وعموما، كان 46.5٪ (698/1502) من الذكور. كان معدل انتشار أي حالة تنفسية مزمنة ذات صلة بالعمر هو 20.2٪. كان معدل انتشار مرض الانسداد الرئوي المزمن ذي الصلة بالعمر أكبر بكثير في المشاركين من المناطق الريفية عنه في المناطق الحضرية (6.1٪ مقابل 1.5٪، على التوالي؛ نسبة الاحتمال0.001)، في حين أن الربو كان أكثر شيوعاً بشكل كبير في المشاركين من المناطق الحضرية: 9.7٪ مقابل 4.4٪ في المشاركين من المناطق الريفية (نسبة الاحتمال0.001). كان معدل انتشار التهاب الشعب الهوائية المزمن ذي الصلة بالعمر مشابهاً في المشاركين من المناطق الريفية والمناطق الحضرية (3.5٪ مقابل 2.2٪، على التوالي؛ نسبة الاحتمال = 0.62)، وكذلك كان الحال في نمط قياس التنفس المقيد (10.9٪ مقابل 9.4٪؛ نسبة الاحتمال = 0.82). بالنسبة لمرض الانسداد الرئوي المزمن، كان الخطر المنسوب للسكان هو 51.5٪ للإقامة في مناطق ريفية، و19.5٪ لتدخين التبغ، و16.0٪ لمؤشر كتلة الجسم الأكبر من 18.5 كجم/م2، و13.0٪ لوجود تاريخ سابق لعلاج السل الرئوي.كان معدل انتشار الأمراض التنفسية المزمنة مرتفعاً في كل المناطق الريفية والحضرية بأوغندا. كان مكان الإقامة أهم عامل خطر لمرض الانسداد الرئوي المزمن والربو.旨在确定乌干达城乡地区的慢性呼吸道疾病患病率，并确定这些疾病的危险因素。.这项基于人口的横断面研究包括年龄在 35 岁或以上的成年人。所有男性均按照标准指南进行肺活量测定，并完成了调查问卷上有关呼吸症状、功能状态和人口学特征的相关问题。监测四种慢性呼吸系统疾病：慢性阻塞性肺病 (COPD)、哮喘、慢性支气管炎和限制性通气功能障碍的患病情况。.共有 1502 名参与者（平均年龄：46.9 岁）有可接受和可重复的肺活量测定结果：837 名 (56%) 来自 Nakaseke 农村地区，665 名 (44%) 来自坎帕拉城区。总体上，46.5% (698/1502) 为男性。所有的慢性呼吸系统疾病的年龄标化患病率为 20.2%。农村参与者的慢性阻塞性肺病年龄标化患病率明显高于城市参与者（分别为 6.1% 和 1.5%；乌干达城乡地区的慢性呼吸道疾病患病率均很高。居住地是慢性阻塞性肺病和哮喘的首要危险因素。.Определить распространенность хронических респираторных заболеваний в сельских и городских районах Уганды и выявить факторы риска для этих заболеваний.Проводилось популяционное перекрестное исследование среди взрослого населения в возрасте от 35 лет. Все участники оценивались посредством спирометрии в соответствии со стандартными рекомендациями. Они заполняли анкеты о респираторных симптомах, своем функциональном состоянии и указывали демографические характеристики. Отслеживалось наличие четырех хронических респираторных заболеваний: хронической обструктивной болезни легких (ХОБЛ), астмы, хронического бронхита и рестриктивных нарушений.Всего было обследовано 1502 участника (средний возраст составил 46,9 года), которые продемонстрировали приемлемые и воспроизводимые результаты спирометрии: 837 (56%) в сельском районе Накасеке и 665 (44%) в городском районе Кампала. Из них 46,5% (698 из 1502 человек) составляли мужчины. Распространенность любого из исследуемых хронических респираторных заболеваний с учетом поправки на возраст составила 20,2%. Распространенность ХОБЛ с учетом поправки на возраст была значительно выше в сельской местности, чем среди участников-горожан (6,1 и 1,5% соответственно,Распространенность хронических респираторных заболеваний и в сельской и в городской местности Уганды оказалась высокой. Наиболее существенным фактором риска для ХОБЛ и астмы оказалось место проживания.

CONTEXT: Observational studies investigating household air pollution (HAP) exposure to biomass fuel smoke as a risk factor for pulmonary tuberculosis have reported inconsistent results. OBJECTIVE: To evaluate the association between HAP exposure and the prevalence of self-reported previous pulmonary tuberculosis. DESIGN: We analyzed pooled data including 12,592 individuals from five population-based studies conducted in Latin America, East Africa, and Southeast Asia from 2010 to 2015. We used multivariable logistic regression to model the association between HAP exposure and self-reported previous pulmonary tuberculosis adjusted for age, sex, tobacco smoking, body mass index, secondary education, site and country of residence. RESULTS: Mean age was 54.6 years (range of mean age across settings 43.8 – 59.6 years) and 48.6% were women (range of % women 38.3% – 54.5%). The proportion of participants reporting HAP exposure was 38.8% (range in % HAP exposure 0.48% – 99.4%). Prevalence of previous pulmonary tuberculosis was 2.7% (range of prevalence 0.6% – 6.9%). While participants with previous pulmonary tuberculosis had a lower pre-bronchodilator FEV(1) (mean -0.7 SDs, 95% CI -0.92 to -0.57), FVC (-0.52 SDs, 95% CI -0.69 to -0.33) and FEV(1)/FVC (-0.59 SDs, 95% CI -0.76 to-0.43) as compared to those who did not, we did not find an association between HAP exposure and previous pulmonary tuberculosis (adjusted odds ratio=0.86; 95% CI 0.56 – 1.32). CONCLUSIONS: There was no association between HAP exposure and self-reported previous pulmonary tuberculosis in five population-based studies conducted worldwide.

Purpose The purpose of this study was to identify potential therapeutic strategies to slow down or prevent the expression of early-onset epithelial to mesenchymal transition (EMT) marker proteins (fibronectin and alpha smooth muscle actin, α-SMA) without sacrificing the synthesis and accumulation of the prosurvival protein vascular endothelial growth factor (VEGF) in cultured virally transformed human lens epithelial (HLE) cells. Methods HLE-B3 cells, maintained in a continuous hypoxic environment (1% oxygen), were treated with SB216763, a specific inhibitor of glycogen synthase kinase-3β (GSK-3β) catalytic activity. Western blot analysis was employed to detect the cytoplasmic and nuclear levels of β-catenin, as well as the total lysate content of fibronectin and α-SMA. Enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of VEGF in cell culture medium. A hypoxia-inducible factor-1α (HIF-1α) translation inhibitor and an HIF-2α translation inhibitor were independently employed to evaluate the effect of hypoxia inducible factor inhibition on EMT marker protein and VEGF expression. XAV932 was used to assess the suppression of nuclear β-catenin and its downstream effect on EMT marker proteins and VEGF expression. Results SB216763-treated HLE-B3 cells caused marked inhibition of GSK-3β activity prompting a significant increase in the translocation of cytoplasmic β-catenin to the nucleus. The enhancement of nuclear β-catenin looked as if it positively correlated with a significant increase in the basal expression of VEGF as well as increased expression of fibronectin and α-SMA. In conjunction with SB216763, coadministration of an HIF-1α translation inhibitor, but not an HIF-2α translation inhibitor, markedly suppressed the expression of fibronectin and α-SMA without affecting VEGF levels. Treatment with XAV932 significantly reduced the level of nuclear β-catenin, but the levels of neither the EMT marker proteins nor VEGF were changed. Conclusions Recently, we reported that nuclear β-catenin, but not HIF-2α, regulates the expression of fibronectin and α-SMA in atmospheric oxygen. In marked contrast, data from the hypoxic condition clearly establish that nuclear β-catenin plays little apparent role in the expression of EMT marker proteins. Instead, the loss of HIF-1α (but not HIF-2α) decreases the expression of the EMT marker proteins without sacrificing the levels of the prosurvival protein VEGF. These findings support the development of a potentially relevant therapeutic strategy to undermine the progression of normal cells to the mesenchymal phenotype in the naturally hypoxic lens without subverting cell viability.

Purpose Loss of integrity of either the inner or outer mitochondrial membrane results in the dissipation of the mitochondrial electrochemical gradient that leads to mitochondrial membrane permeability transition (mMPT). This study emphasizes the role of glycogen synthase kinase 3beta (GSK-3β) in maintaining mitochondrial membrane potential, thus preventing mitochondrial depolarization (hereafter termed mitoprotection). Using 3-(2,4-dichlorophenyl)-4-(1-methyl-1H-indol-3-yl)-1H-pyrrole-2,5-dione (SB216763), an inhibitor of GSK-3β, and drawing a distinction between it and 1,4-diamino-2,3-dicyano-1,4-bis[2-aminophenylthio] butadiene (UO126), an inhibitor of extracellular-signal-regulated kinase (ERK) phosphorylation, the means by which GSK-3β influences mitoprotection in cultured human lens epithelial (HLE-B3) cells and normal, secondary cultures of bovine lens epithelial cells, maintained in atmospheric oxygen, was investigated. Methods Virally transfected human lens epithelial cells (HLE-B3) and normal cultures of bovine lens epithelial cells were exposed to acute hypoxic conditions (about 1% O2) followed by exposure to atmospheric oxygen (about 21% O2). Specific antisera and western blot analysis was used to examine the state of phosphorylation of ERK and GSK-3β, as well as the phosphorylation of a downstream substrate of GSK-3β, glycogen synthase (GS, useful in monitoring GSK-3β activity). The potentiometric dye, 1H-benzimidazolium-5,6-dichloro-2-[3-(5,6-dichloro-1,3-diethyl-1,3-dihydro-2H-benzimidazol-2-ylidene)-1-propenyl]-1,3-diethyl-iodide (JC-1), was used to monitor mitochondrial depolarization upon exposure of inhibitor treatment relative to the control cells (mock inhibition) in atmospheric oxygen. Caspase-3 activation was scrutinized to determine whether mitochondrial depolarization inevitably leads to apoptosis. Results Treatment of HLE-B3 cells with SB216763 (12 µM) inactivated GSK-3β activity as verified by the enzyme’s inability to phosphorylate its substrate, GS. SB216763-treated cells were not depolarized relative to the control cells as demonstrated with JC-1 fluorescent dye analysis. The HLE-B3 cells treated with UO126, which similarly blocked phosphorylation of GS, were nevertheless prone to mMPT relative to the control cells. Western blot analysis determined that Bcl-2-associated X (BAX) levels were unchanged for SB216763-treated or UO126-treated HLE-B3 cells when compared to their respective control cells. However, unlike the SB216763-treated cells, the UO126-treated cells showed a marked absence of Bcl-2, as well as phosphorylated Bcl-2 relative to the controls. UO126 treatment of bovine lens epithelial cells showed similar results with pBcl-2 levels, while the Bcl-2 content appeared unchanged relative to the control cells. HLE-B3 and normal bovine lens cell cultures showed susceptibility to mMPT associated with the loss of pBcl-2 by UO126 treatment. Conclusions Mitochondrial depolarization may occur by one of two key occurrences: interruption of the electrochemical gradient across the inner mitochondrial membrane resulting in mMPT or by disruption of the integrity of the inner or outer mitochondrial membrane. The latter scenario is generally tightly regulated by members of the Bcl-2 family of proteins. Inhibition of GSK-3β activity by SB216763 blocks mMPT by preventing the opening of the mitochondrial permeability transition pore. UO126, likewise, inhibits GSK-3β activity, but unlike SB216763, inhibition of ERK phosphorylation induces the loss of intracellular pBcl-2 levels under conditions where intracellular BAX levels remain constant. These results suggest that the lenticular mitoprotection normally afforded by the inactivation of GSK-3β activity may, however, be bypassed by a loss of pBcl-2, an anti-apoptotic member of the Bcl-2 family. Bcl-2 prevents the translocation of BAX to the mitochondrial outer membrane inhibiting depolarization by disrupting the normal electrochemical gradient leading to mMPT.

Purpose The prosurvival signaling cascades that mediate the unique ability of human lens epithelial cells to survive in their naturally hypoxic environment are not well defined. Hypoxia induces the synthesis of the hypoxia inducible factor HIF-1α that in turn, plays a crucial role in modulating a downstream survival scheme, where vascular endothelial growth factor (VEGF) also plays a major role. To date, no published reports in the lens literature attest to the expression and functionality of HIF-2α and the role it might play in regulating VEGF expression. The aim of this study was to identify the functional expression of the hypoxia inducible factors HIF-1α and HIF-2α and establish their role in regulating VEGF expression. Furthermore, we demonstrate a link between sustained VEGF expression and the ability of the hypoxic human lens epithelial cell to thrive in low oxygen conditions and resist mitochondrial membrane permeability transition (also referred to as lenticular cytoprotection). Methods Hypoxia inducible factor translation inhibitors were used to demonstrate the role of HIF-1α and HIF-2α and the simultaneous expression of both hypoxic inducible factors to determine their role in regulating VEGF expression. Axitinib, which inhibits lenticular cell autophosphorylation of its VEGF receptor, was employed to demonstrate a role for the VEGF–VEGFR2 receptor complex in regulating Bcl-2 expression. Specific antisera and western blot analysis were used to detect the protein levels of HIF-1α and HIF-2α, as well as the proapoptotic protein, BAX and the prosurvival protein, Bcl-2. VEGF levels were analyzed with enzyme-linked immunosorbent assay (ELISA). The potentiometric dye, 5,5′,6,6′-tetrachloro1,1′,3,3′-tetraethyl-benzimidazolylcarbocyanine iodide, was used to determine the effect of the inhibitors on mitochondrial membrane permeability transition. Results Cultured human lens epithelial cells (HLE-B3) maintained under hypoxic condition (1% oxygen) displayed consistent accumulation of VEGF throughout the 72 h incubation period. Using hypoxia inducible factor translation inhibitors targeting HIF-1α or HIF-2α, the specific inhibition of each protein did not diminish VEGF synthesis. The combined inhibition of HIF-1α and HIF-2α expression, using a double hypoxia inducible factor translation inhibitor, markedly decreased the level of VEGF. The inhibition of VEGF synthesis was associated with a profound deficiency in the level of the prosurvival protein, Bcl-2. Axitinib also prevented the VEGF-mediated expression of Bcl-2. The loss of VEGF coupled with the decrease in intracellular Bcl-2 correlated with marked mitochondrial depolarization, an early predictor of cellular apoptosis. Conclusions Our data support a model in which the sustained synthesis of VEGF in human lens epithelial cells, maintained under hypoxic condition, is regulated by a compensatory inter-relationship between HIF-1α and HIF-2α. VEGF acts as a prosurvival factor in hypoxic lens epithelial cells by maintaining consistent expression of the prosurvival protein Bcl-2, which likely prevents the translocation of cytosolic BAX to the outer mitochondrial membrane, thus preventing the initiation of mitochondrial depolarization.

Tobacco smoking is a major risk factor for chronic disease. A previous study found that self-reported (SR) tobacco smoking was low in a low-resource area of Lima, Peru. We compared SR smoking with levels of urine cotinine (UC) to validate the reported prevalence. Data were obtained via survey in population-based samples of urban Lima and peri-urban Tumbes, Peru. SR smoking was compared to UC taken from the same participants after the survey. SR status was characterized as non- versus current (includes occasional and daily (≥1 cig/day)) smoking. UC of ≥100 ng/mL indicates daily smoking. Our sample (N=382) included 13.61% current and 4.71% daily smokers by SR. Daily smokers were mean 53.7 years old and 61.1% male. SR overstated current smoking prevalence by UC in our sample (8.90% difference [4.86-12.94]) and validated daily smoking (0.03% difference [-3.01-3.01]). Mean UC among current smokers was 111.21 (med=0); among daily it was 277.97 (med=148.20). In age and sex-adjusted multiple logistic regression, current (OR=15.12 [5.03-45.50]) and daily smoking (OR=56.09 [16.81-187.10]) were associated with UC>100 ng/mL, however the c-statistic for daily was higher (0.878 vs. 0.824). Further, the Kappa statistic between SR smoking and high UC was higher for daily smoking (0.534) than current (0.293), indicating better agreement. Daily smoking proved a more valid and relevant indicator than current smoking for epidemiological studies. Additionally, UC validated SR estimates of low smoking in a population-based sample in Peru. This evidence supports the implementation of programs for primary prevention of smoking in the region.

BACKGROUND: Allergic diseases are increasing in sub-Saharan Africa but few studies have characterized the burden among adults. OBJECTIVE: We conducted a study to evaluate the prevalence and risk factors of allergic disorders in urban and rural Uganda. METHODS: We present a cross-sectional analysis of enrollment data from a population-based cohort study of adults aged ≥35 years in urban and rural, Uganda. Sociodemographic and both lifetime and 12-month respiratory symptoms data were collected and spirometry was conducted following standard guidelines. RESULTS: In 1,308 adults, median age 43.8 years and 52.3% female, we found an age-adjusted prevalence of 6.8% for asthma (9.8% urban, 4.3% rural; p