Cross-Sectional Evaluation of Potential Volatile Organic Compound Exposures Around U.S. Schools

Volatile Organic Compounds (VOCs), characterized by high vapor pressure and low water solubility, exist in gaseous phase at room temperature. Previous studies have suggested exposure to VOCs may be associated with adverse health effects such as asthma exacerbation and in some cases cancer. The major sources of outdoor VOCs include traffic and industrial emissions. Ambient VOCs can react with Nitrogen Oxides (NOx) in the presence of sunlight to form ground level ozone, one of the U.S. Environmental Protection Agency (EPA) Criteria Air Pollutants. This thesis was designed to investigate the potential VOCs exposure among U.S. schoolchildren. Moreover, the influence of various neighborhood factors (urban vs. rural areas, distance from highways, presence/absence of industries) on VOCs concentrations around U.S. Schools was investigated. The findings of this thesis suggest that schools in urban areas, near industries and traffic activity have higher concentrations of VOCs compared to those not possessing such characteristics

Effets du vérapamil et ses dérivés (le D600 et le D888) sur le canal calcique de type R cardiaque et de muscle lisse vasculaire

Les effets du vérapamil et ses dérivés, le D600 et le D888, ont été étudiés sur un nouveau type de canal calcique, le canal calcique de type R, activé par une dépolarisation soutenue ou par l'insuline dans les cellules cardiaques et de muscle lisse vasculaire. Cette étude a été faite à l'aide de techniques de mesure de Ca2+ libre intracellulaire utilisant le Fura-2. Dans les différents types de cellules cardiaques étudiés, soient chez l'embryon de poulet et le fœtus humain, ainsi que chez les cellules de muscle lisse vasculaire (MLV) provenant de l'aorte de lapin, le vérapamil, le D600 et le D888 n'ont eu aucun effet significatif, même en présence d'un bloqueur spécifique du canal calcique de type L, sur la phase soutenue de Ca2+ intracellulaire induite après une dépolarisation soutenue de la membrane cellulaire ou par superfusion continue avec l'insuline. Le vérapamil, ainsi que ses dérivés, n'ont eu aucun effet sur le niveau basal de calcium intracellulaire. Lorsque les cellules cardiaques et de muscle lisse vasculaire étaient prétraitées avec le (-) vérapamil, et non le (+) vérapamil, ce composé a prévenu de façon significative l'activation du canal calcique de type R par la dépolarisation soutenue ou par l'insuline. Ces résultats démontrent que le (-) vérapamil joue un rôle dans la prévention de l'activation du canal R par l'insuline, et suggère que ce composé peut jouer un rôle dans la prévention de l'hypertension associée au diabète insulino-résistant (type II)

Effets du vérapamil et ses dérivés (le D600 et le D888) sur le canal calcique de type R cardiaque et de muscle lisse vasculaire

Les effets du vérapamil et ses dérivés, le D600 et le D888, ont été étudiés sur un nouveau type de canal calcique, le canal calcique de type R, activé par une dépolarisation soutenue ou par l'insuline dans les cellules cardiaques et de muscle lisse vasculaire. Cette étude a été faite à l'aide de techniques de mesure de Ca2+ libre intracellulaire utilisant le Fura-2. Dans les différents types de cellules cardiaques étudiés, soient chez l'embryon de poulet et le fœtus humain, ainsi que chez les cellules de muscle lisse vasculaire (MLV) provenant de l'aorte de lapin, le vérapamil, le D600 et le D888 n'ont eu aucun effet significatif, même en présence d'un bloqueur spécifique du canal calcique de type L, sur la phase soutenue de Ca2+ intracellulaire induite après une dépolarisation soutenue de la membrane cellulaire ou par superfusion continue avec l'insuline. Le vérapamil, ainsi que ses dérivés, n'ont eu aucun effet sur le niveau basal de calcium intracellulaire. Lorsque les cellules cardiaques et de muscle lisse vasculaire étaient prétraitées avec le (-) vérapamil, et non le (+) vérapamil, ce composé a prévenu de façon significative l'activation du canal calcique de type R par la dépolarisation soutenue ou par l'insuline. Ces résultats démontrent que le (-) vérapamil joue un rôle dans la prévention de l'activation du canal R par l'insuline, et suggère que ce composé peut jouer un rôle dans la prévention de l'hypertension associée au diabète insulino-résistant (type II)

Same-day HIV testing with initiation of antiretroviral therapy versus standard care for persons living with HIV: A randomized unblinded trial

Background: Attrition during the period from HIV testing to antiretroviral therapy (ART) initiation is high worldwide. We assessed whether same-day HIV testing and ART initiation improves retention and virologic suppression. Methods and findings We conducted an unblinded, randomized trial of standard ART initiation versus same-day HIV testing and ART initiation among eligible adults ≥18 years old with World Health Organization Stage 1 or 2 disease and CD4 count ≤500 cells/mm3. The study was conducted among outpatients at the Haitian Group for the Study of Kaposi’s Sarcoma and Opportunistic infections (GHESKIO) Clinic in Port-au-Prince, Haiti. Participants were randomly assigned (1:1) to standard ART initiation or same-day HIV testing and ART initiation. The standard group initiated ART 3 weeks after HIV testing, and the same-day group initiated ART on the day of testing. The primary study endpoint was retention in care 12 months after HIV testing with HIV-1 RNA <50 copies/ml. We assessed the impact of treatment arm with a modified intention-to-treat analysis, using multivariable logistic regression controlling for potential confounders. Between August 2013 and October 2015, 762 participants were enrolled; 59 participants transferred to other clinics during the study period, and were excluded as per protocol, leaving 356 in the standard and 347 in the same-day ART groups. In the standard ART group, 156 (44%) participants were retained in care with 12-month HIV-1 RNA <50 copies, and 184 (52%) had <1,000 copies/ml; 20 participants (6%) died. In the same-day ART group, 184 (53%) participants were retained with HIV-1 RNA <50 copies/ml, and 212 (61%) had <1,000 copies/ml; 10 (3%) participants died. The unadjusted risk ratio (RR) of being retained at 12 months with HIV-1 RNA <50 copies/ml was 1.21 (95% CI: 1.04, 1.38; p = 0.015) for the same-day ART group compared to the standard ART group, and the unadjusted RR for being retained with HIV-1 RNA <1,000 copies was 1.18 (95% CI: 1.04, 1.31; p = 0.012). The main limitation of this study is that it was conducted at a single urban clinic, and the generalizability to other settings is uncertain. Conclusions: Same-day HIV testing and ART initiation is feasible and beneficial in this setting, as it improves retention in care with virologic suppression among patients with early clinical HIV disease. Trial registration This study is registered with ClinicalTrials.gov number NCT0190008

Intersectional Impacts of the 2021 Mw 7.2 Nippes, Haiti, Earthquake from Geotechnical and Social Perspectives

The Mw 7.2 Nippes, Haiti, earthquake occurred on 14 August 2021 in Haiti's southwest peninsula and in the midst of significant social, economic, and political crises. A hybrid reconnaissance mission (i.e., combined remote and field investigation) was coordinated to document damage to the built environment after the event. This article evaluates two ground-motion records available in Haiti in the context of the geology of the region and known areas with significant damage, such as Les Cayes. We also present a new map of time-averaged shear-wave velocity values to 30 m depth (VS30) for Les Cayes and Port-au-Prince based on the geostatistical approach of kriging and accounting for region -spe-cific geology proxies and field measurements of VS30. Case studies of ground failure obser-vations, including landslides and liquefaction triggering, are described as well as the intersection of social and engineering observations. Maps depicting this important inter-section are provided to facilitate the assessment of how natural hazards and social con-flicts have influenced the vulnerability of Haiti's population to earthquakes

S-nitrosylation of cysteine 289 of the AT(1) receptor decreases its binding affinity for angiotensin II

1. Nitric oxide (NO) is known to affect the properties of various proteins via the S-nitrosylation of cysteine residues. This study evaluated the direct effects of the NO donor sodium nitroprusside (SNP) on the pharmacological properties of the AT(1) receptor for angiotensin II expressed in HEK-293 cells. 2. SNP dose-dependently decreased the binding affinity of the AT(1) receptor without affecting its total binding capacity. This modulatory effect was reversed within 5 min of removing SNP. 3. The effect of SNP was not modified in the presence of the G protein uncoupling agent GTPγS or the soluble guanylyl cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one. 4. The binding properties of a mutant AT(1) receptor in which all five cysteine residues within the transmembrane domains had been replaced by serine was not affected by SNP. Systematic analysis of mutant AT(1) receptors revealed that cysteine 289 conferred the sensitivity to SNP. 5. These results suggest that NO decreased the binding affinity of the AT(1) receptor by S-nitrosylation of cysteine 289. This modulatory mechanism may be particularly relevant in pathophysiological situations where the beneficial effects of NO oppose the deleterious effects of angiotensin II