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The Croton watershed, which has supplied millions of gallons of water to New Yorkers for 150 years, remains remarkably pure and requires no filtration. However, a battle over the watershed is brewing because the EPA says New York must build a water treatment facility, but many residents would rather rely on well-stewarded soils and streams to keep the water clean.

An easy-to-construct field porometer facilitates rapid field (or laboratory) determination of external capillary water volume held at measured hydrostatic forces (=water potential) in bryophyte colonies. This instrument measures pressure and water volume in the ranges where bryophytes are physiologically active. Construction of the apparatus utilizes materials readily available in many laboratories. Evidence gathered thus far indicates that the filling and emptying curves are characteristic of species, scale, and packing strategy in bryophyte colonies. This instrument makes it possible to test hypotheses relating the differential distributions of bryophytes to clines of water potential and the size of capillary conducting spaces between organs and axes. For the first time, direct field measurement may be taken of the volume of water absorbed and held at hydrostatic pressures characteristic of the external capillary water conducting systems of whole bryophyte colonies.

Congenital adrenal hyperplasia with apparent combined P450C17 and P450C21 deficiency is associated with accumulation of steroid metabolites, indicating impaired activity of 17α-hydroxylase and 21-hydroxylase. However, no mutations have been reported in the CYP17 and CYP21 genes, which encode these P450 enzymes. Affected girls are born with ambiguous genitalia, but their circulating androgens are low, and virilisation does not progress. We aimed to investigate the underlying molecular basis of congenital adrenal hyperplasia with apparent combined P450C17 and P450C21 deficiency in affected children. We did sequence analysis of the human gene encoding P450 oxidoreductase, an enzyme that is important in electron transfer from NADPH to P450C17 and P450C21. We studied two unrelated families with a total of three affected children and 100 healthy controls. Wild-type and mutant P450 oxidoreductase proteins were bacterially expressed, purified, and assayed for cytochrome c reductase activity. We identified four mutations encoding single aminoacid changes in P450 oxidoreductase. All patients were compound heterozygotes, whereas their parents and an unaffected sibling harboured a mutation in only one allele. By contrast, no mutations were noted in the controls. Bacterial expression of recombinant mutant proteins revealed deficient or reduced enzyme activity. Molecular pathogenesis of this form of congenital adrenal hyperplasia is caused by mutations in the gene encoding P450 oxidoreductase. Deficiency of this enzyme could suggest an alternative pathway in human androgen synthesis, present only in fetal life, which explains the combination of antenatal androgen excess and postnatal androgen deficiency. Published online June 14,2004 http://image.thelancet.com/extras/04art4419web.pdf

Background Each year, 5.6 million new syphilis cases are diagnosed globally. Guidelines for people living with HIV (PLWH) in low-income countries (LIC) recommend STI testing for symptomatic persons and those newly diagnosed with HIV; routine STI testing is less clear. Here we provide updated syphilis prevalence and identify co-infection risk factors in PLWH in the African Cohort Study (AFRICOS) to understand these rates as they relate to syndromic treatment. Methods AFRICOS is a study enrolling PLWH and HIV-uninfected individuals in four African countries. Participant study enrollment information was used to determine syphilis prevalence and co-infection risk factors. Inclusion criteria consisted of adults 18 years or older receiving care at a participating clinic as a long-term resident who consented to data and specimen collection. Exclusion criteria consisted of pregnancy and/or imprisonment. Screen-positive syphilis was defined as a reactive rapid plasma regain (RPR) upon study enrollment whereas confirmed syphilis included a reactive RPR followed by reactive treponemal test. Multivariate analyses was performed to determine HIV and syphilis co-infection risk factors. Results Between 2013 and March 1, 2020, 2939 PLWH enrolled and 2818 were included for analysis. Screen-positive and confirmed syphilis prevalence were 5.3% (151/2818) and 3.1% (87/2818), respectively. When the analysis was restricted to PLWH with an RPR titer of greater than, or equal to, 1:8, 11/87 (12.6%) participants were included. No PLWH and confirmed syphilis had documented genital ulcers. In the multivariate model, participants with confirmed syphilis co-infection were more likely to have none or some primary education [aOR 3.29 (1.60, 6.74)] and consume alcohol [aOR 1.87 (1.16, 3.03)] compared to those without syphilis. Antiretroviral therapy (ART) with suppressed viral load (VL) was protective in the unadjusted model but not adjusted multivariate model. Conclusions Our findings show that syphilis rates in sub-Saharan Africa remain elevated where diagnosis remains challenging, and that both lower education level and alcohol consumption are significantly associated with HIV/syphilis co-infection in AFRICOS. Based on our analysis, current STI guidelines targeting testing for African individuals with either new HIV diagnosis or syndromic symptoms may be inadequate, highlighting the need for increased testing and treatment strategies in resource-limited settings.

Background Retention in clinical care is important for people living with HIV (PLWH). Evidence suggests that missed clinic visits are associated with interruptions in antiretroviral therapy (ART), lower CD4 counts, virologic failure, and overlooked coinfections. We identified factors associated with missed routine clinic visits in the African Cohort Study (AFRICOS). Methods In 2013, AFRICOS began enrolling people with and without HIV in Uganda, Kenya, Tanzania, and Nigeria. At enrollment and every 6 months thereafter, sociodemographic questionnaires are administered and clinical outcomes assessed. Missed clinic visits were measured as the self-reported number of clinic visits missed in the past 6 months and dichotomized into none or one or more visits missed. Logistic regression with generalized estimating equations was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between risk factors and missed visits. Results Between January 2013 and March 2020, 2937 PLWH were enrolled, of whom 2807 (95.6%) had initiated ART and 2771 had complete data available for analyses. Compared to PLWH 50+, missed clinic visits were more common among those 18–29 years (aOR 2.33, 95% CI 1.65–3.29), 30–39 years (aOR 1.59, 95% CI 1.19–2.13), and 40–49 years (aOR 1.42, 95% CI 1.07–1.89). As compared to PLWH on ART for < 2 years, those on ART for 4+ years were less likely to have missed clinic visits (aOR 0.72, 95% CI 0.55–0.95). Missed clinic visits were associated with alcohol use (aOR 1.34, 95% CI 1.05–1.70), a history of incarceration (aOR 1.42, 95% CI 1.07–1.88), depression (aOR 1.47, 95% CI 1.13–1.91), and viral non-suppression (aOR 2.50, 95% CI 2.00–3.12). As compared to PLWH who did not miss any ART in the past month, missed clinic visits were more common among those who missed 1–2 days (aOR 2.09, 95% CI 1.65–2.64) and 3+ days of ART (aOR 7.06, 95% CI 5.43–9.19). Conclusions Inconsistent clinic attendance is associated with worsened HIV-related outcomes. Strategies to improve visit adherence are especially needed for young PLWH and those with depression.