Development of nematode resistance in Arabidopsis by HD-RNAi-mediated silencing of the effector gene Mi-msp2.

Root-knot nematodes (RKNs) are devastating parasites that infect thousands of plants. As RKN infection is facilitated by oesophageal gland effector genes, one such effector gene, Mi-msp2, was selected for a detailed characterization. Based on domain analysis, the Mi-MSP2 protein contains an ShKT domain, which is likely involved in blocking K+ channels and may help in evading the plant defence response. Expression of the Mi-msp2 gene was higher in juveniles (parasitic stage of RKNs) than in eggs and adults. Stable homozygous transgenic Arabidopsis lines expressing Mi-msp2 dsRNA were generated, and the numbers of galls, females and egg masses were reduced by 52-54%, 60-66% and 84-95%, respectively, in two independent RNAi lines compared with control plants. Furthermore, expression analysis revealed a significant reduction in Mi-msp2 mRNA abundance (up to 88%) in female nematodes feeding on transgenic plants expressing dsRNA, and northern blot analysis confirmed expression of the Mi-msp2 siRNA in the transgenic plants. Interestingly, a significant reduction in the reproduction factor was observed (nearly 40-fold). These data suggest that the Mi-msp2 gene can be used as a potential target for RKN management in crops of economic importance.

Physiological, anatomical and transcriptional alterations in a rice mutant leading to enhanced water stress tolerance.

Water stress is one of the most severe constraints to crop productivity. Plants display a variety of physiological and biochemical responses both at the cellular and whole organism level upon sensing water stress. Leaf rolling, stomatal closure, deeper root penetration, higher relative water content (RWC) and better osmotic adjustment are some of the mechanisms that plants employ to overcome water stress. In the current study, we report a mutant, enhanced water stress tolerant1 (ewst1) with enhanced water stress tolerance, identified from the ethyl methanesulfonate-induced mutant population of rice variety Nagina22 by field screening followed by withdrawal of irrigation in pots and hydroponics (PEG 6000). Though ewst1 was morphologically similar to the wild type (WT) for 35 of the 38 morphological descriptors (except chalky endosperm/expression of white core, decorticated grain colour and grain weight), it showed enhanced germination in polyethylene glycol-infused medium. It exhibited increase in maximum root length without any significant changes in its root weight, root volume and total root number on crown when compared with the WT under stress in PVC tube experiment. It also showed better performance for various physiological parameters such as RWC, cell membrane stability and chlorophyll concentration upon water stress in a pot experiment. Root anatomy and stomatal microscopic studies revealed changes in the number of xylem and phloem cells, size of central meta-xylem and number of closed stomata in ewst1. Comparative genome-wide transcriptome analysis identified genes related to exocytosis, secondary metabolites, tryptophan biosynthesis, protein phosphorylation and other signalling pathways to be playing a role in enhanced response to water stress in ewst1. The possible involvement of a candidate gene with respect to the observed morpho-physiological and transcriptional changes and its role in stress tolerance are discussed. The mutant identified and characterized in this study will be useful for further dissection of water stress tolerance in rice.

Consensus statement on diabetes in children.

While T1DM has been traditionally seen as a minor concern in the larger picture of pediatric ailments, new data reveals that the incidence of T1DM has assumed alarming proportions. It has long been clear that while the disease may be diagnosed at an early age, its impact is not isolated to afflicted children. The direct impact of the disease on the patient is debilitating due to the nature of the disease and lack of proper access to treatment in India. But this impact is further compounded by the utter apathy and often times antipathy, which patients withT1DM have to face. Lack of awareness of the issue in all stakeholders, low access to quality healthcare, patient, physician, and system level barriers to the delivery of optimal diabetes care are some of the factors which hinder successful management of T1DM. The first international consensus meet on diabetes in children was convened with the aim of providing a common platform to all the stakeholders in the management of T1DM, to discuss the academic, administrative and healthcare system related issues. The ultimate aim was to articulate the problems faced by children with diabetes in a way that centralized their position and focused on creating modalities of management sensitive to their needs and aspirations. It was conceptualized to raise a strong voice of advocacy for improving the management of T1DM and ensuring that "No child should die of diabetes". The unique clinical presentations of T1DM coupled with ignorance on the part of the medical community and society in general results in outcomes that are far worse than that seen with T2DM. So there is a need to substantially improve training of HCPs at all levels on this neglected aspect of healthcare.

Uptake of HIV testing and HIV positivity among presumptive tuberculosis patients at Puducherry, South India.

SETTING: Puducherry, a district in South India with a low prevalence of human immunodeficiency virus (HIV) infection (<1% among antenatal women). OBJECTIVES: 1) To estimate the proportion of patients with known HIV status who were HIV-positive, 2) to describe the demographic and clinical characteristics of patients with unknown HIV status among presumptive TB patients, and 3) to assess the additional workload at HIV testing centres. DESIGN: In this cross-sectional study, consecutive presumptive TB patients attending microscopy centres for diagnosis during March-May 2013 were asked if they knew their HIV status. Patients with unknown HIV status were offered voluntary counselling and HIV testing. RESULTS: Of 1886 presumptive TB patients, HIV status was ascertained for 842 (44.6%); 28 (3.3%) were HIV-positive. The uptake of HIV testing was significantly higher in younger age groups, males, residents of Puducherry and smear-positive TB patients. The median increase in the number of clients tested for HIV per day per testing centre was 1 (range 0-6). CONCLUSION: The uptake of HIV testing was low. HIV prevalence was higher among presumptive TB patients than in antenatal women, and as high as in TB patients. With minimal increase in workload at HIV testing centres, HIV testing could be implemented using existing resources.

Determining exchange splitting in a magnetic semiconductor by spin-filter tunneling.

A large exchange splitting of the conduction band in ultrathin films of the ferromagnetic semiconductor EuO was determined quantitatively, by using EuO as a tunnel barrier and fitting the current-voltage characteristics and temperature dependence to tunneling theory. This exchange splitting leads to different tunnel barrier heights for spin-up and spin-down electrons and is large enough to produce a near-fully spin-polarized current. Moreover, the magnetic properties of these ultrathin films (<6 nm) show a reduction in Curie temperature with decreasing thickness, in agreement with theoretical calculation [R. Schiller, Phys. Rev. Lett. 86, 3847 (2001)10.1103/Phys. Rev. Lett.86.3847].

Large spin diffusion length in an amorphous organic semiconductor.

We directly measured a spin diffusion length (lambdas) of 13.3 nm in amorphous organic semiconductor (OS) rubrene (C42H28) by spin polarized tunneling. In comparison, no spin-conserved transport has been reported in amorphous Si or Ge. Absence of dangling bond defects can explain the spin transport behavior in amorphous OS. Furthermore, when rubrene barriers were grown on a seed layer, the elastic tunneling characteristics were greatly enhanced. Based on our findings, lambdas in single-crystalline rubrene can be expected to reach even millimeters, showing the potential for organic spintronics development.