Changes in Sexual Risk Behavior in the Mombasa Cohort: 1993–2007

The Mombasa Cohort is an open cohort study following HIV-seronegative women reporting transactional sex. Established in 1993, the cohort provides regular HIV counseling and testing at monthly visits. Over time, HIV acquisition risk has declined steadily in this cohort. To evaluate whether this decline may reflect changes in sexual risk behavior, we investigated trends in condom use and partner numbers among women who participated in the Mombasa Cohort between 1993 and 2007. Multinomial logistic regression and generalized estimating equations were used to evaluate the association of calendar time and follow-up time with key risk behaviors, after adjustment for potential confounding factors. At enrollment visits by 1,844 women, the adjusted probability of never using condoms decreased over time, from 34.2% to 18.9%. Over 23,911 follow-up visits, the adjusted probabilities of reporting >2 partners decreased from 9.9% to 4.9% and inconsistent condom use decreased from 7.9% to 5.3% after ≥12 cohort visits. Important predictors of risk behavior were work venue, charging low fees for sex, and substance abuse. Women with a later sexual debut had less risky behavior. Although sexual risk has declined among women participating in the Mombasa Cohort, HIV acquisition continues to occur and interventions to promote and reinforce safer sex are clearly needed.     

Genomics and molecular breeding in lesser explored pulse crops: Current trends and future opportunities

Pulses are multipurpose crops for providing income, employment and food security in the underprivileged regions, notably the FAO-defined low-income food-deficit countries. Owing to their intrinsic ability to endure environmental adversities and the least input/management requirements, these crops remain central to subsistence farming. Given their pivotal role in rain-fed agriculture, substantial research has been invested to boost the productivity of these pulse crops. To this end, genomic tools and technologies have appeared as the compelling supplement to the conventional breeding. However, the progress in minor pulse crops including dry beans (Vigna spp.), lupins, lablab, lathyrus and vetches has remained unsatisfactory, hence these crops are often labeled as low profile or lesser researched. Nevertheless, recent scientific and technological breakthroughs particularly the next generation sequencing (NGS) are radically transforming the scenario of genomics and molecular breeding in these minor crops. NGS techniques have allowed de novo assembly of whole genomes in these orphan crops. Moreover, the availability of a reference genome sequence would promote re-sequencing of diverse genotypes to unlock allelic diversity at a genome-wide scale. In parallel, NGS has offered high-resolution genetic maps or more precisely, a robust genetic framework to implement whole-genome strategies for crop improvement. As has already been demonstrated in lupin, sequencing-based genotyping of the representative sample provided access to a number of functionally-relevant markers that could be deployed straight away in crop breeding programs. This article attempts to outline the recent progress made in genomics of these lesser explored pulse crops, and examines the prospects of genomics assisted integrated breeding to enhance and stabilize crop yields.     

PSPDB: Plant Stress Protein Database

Plants produce various proteins to overcome biotic and abiotic stresses. Current plant stress databases report plant genes without protein annotations specific to these stresses. To date, according to our findings, a unique plant stress protein database for both biotic and abiotic stresses is not available explicitly for plant biologists that describe linking out to other related databases. This need initiated us to formulate a distinctive database that includes important resources for stress-based factors. We developed the Plant Stress Protein Database (PSPDB), a web-accessible resource that covers 2,064 manually curated plant stress proteins from a wide array of 134 plant species with 30 different types of biotic and abiotic stresses. Functional and experimental validation of proteins associated with biotic and abiotic stresses has been employed as the sole criterion for inclusion in the database. The database is available at http://www.bioclues.org/pspdb/.     

Effect of potassium chloride and calcium chloride induced stress on in vitro cultures of Bacopa monnieri (L.) Pennell and accumulation of medicinally important bacoside A

Growth, osmotic adjustment, antioxidant enzyme defense and principle medicinal component bacoside A was studied in in vitro raised shoots of Bacopa monnieri under different concentrations of KCl and CaCl₂ (0, 50, 100, 150 or 200 mM). Significant reduction was observed in shoot number per culture; shoot length, fresh weight, dry weight and tissue water content (TWC) when shoots were exposed to increasing KCl and CaCl₂ concentrations (50–200 mM) as compared to control. Minimum damage to the membrane as assessed by malondialdehyde (MDA) content was noticed in control in contrast to sharp increase in KCl and CaCl₂ stressed shoots. Higher amounts of free proline, glycine betaine and total soluble sugars (TSS) accumulated in KCl and CaCl₂ exposed shoots compared to the controls. Among different concentrations of KCl and CaCl₂, increasing concentration of CaCl₂ showed more increase in osmolyte accumulation. Na⁺ content decreased with increasing concentrations of KCl and CaCl₂. Accumulation of K⁺ increased significantly in KCl (50–100 mM) stressed shoots as compared to control, while it decreased in CaCl₂ treated shoots indicating that it prevents the uptake of K⁺ ions. Ca²⁺ accumulation significantly increased with increasing concentrations of CaCl₂ up to 150 mM but decreased at higher concentrations. Shoots treated with KCl and CaCl₂ (0–100 mM) showed higher antioxidant enzyme (SOD, CAT, APX and GPX) activities but KCl suppressed the activities at higher concentrations. Accumulation of bacoside A was enhanced with an increase in KCl and CaCl₂ concentration up to 100 mM. It appears from the data that accumulation of osmolytes, and elevated activities of antioxidant enzymes play an important role in osmotic adjustment in shoot cultures of Bacopa and the two salts tested have a positive effect on bacoside accumulation.