NMR studies on truncated sequences of human telomeric DNA: observation of a novel A-tetrad

The structure of the telomeric DNA has been a subject of extensive investigation in recent years due to the realization that it has important functional roles to play in vivo and the observations that truncated telomeric sequences exhibit a great variety of 3D structures in aqueous solutions. In this context, we describe here NMR structural studies on two truncated human telomeric DNA sequences, d-AG3T and d-TAG3T in solutions containing K+ ions. The G3 stretches in both the oligonucleotides were seen to form parallel-stranded quadruplexes. However, the AG3 segment as a whole, had different structural characteristics. The structure of d-AG3T revealed the formation of a novel A-tetrad, which was not seen in d-TAG3T. The A's in the tetrad had syn glycosidic conformation as opposed to the anti conformation of the G's in the G-tetrads. The A-tetrad stacked well over the adjacent G-tetrad and the twist angle at this step was smaller in d-AG3T than in d-TAG3T. These observations are expected to be significant from the point of view of structural diversity and recognition in telomeres

A Rare Case of Situs Inversus with Mesocardia

A ten year old male child having congenital heart disease admitted with recurrent history of respiratory infection. ECHO cardioraphy showed Mesocardia, congenitally corrected TGA, bidirectional VSD and severe pulmonary valve stenosis.On sonographic evaluation showed intra-abdominal mirror imaging of all the solid organs and vessels which was suggestive of a rare presentation of Sinus inverses with Mesocardia. Corrective surgery as pulmonary valve balloon dilation or valvuloplasty and vestricular septal repair has to be done to the child for better morbidity and reducing the mortality risk. This anomaly complicates the diagnosis and management of acute abdominal conditions like appendicitis, diverticulitis and biliary coli

Salinity Tolerance of Forage Range Legumes during Germination and Early Seedling Growth

Salinity is one of the rising problems causing tremendous yield losses in many regions of the world especially in arid and semiarid regions. In India, about 5.95M ha areas were affected by salinity. Five states viz. Haryana, Punjab, Rajasthan, Gujarat and Andhra Pradesh accounts for 48% of the total salt affected soils of the country. Establishment of seedlings at early growth stages of crop plants as one of the most important determinants of high yield is severely affected by soil salinity. Increasing salinity levels significantly decreased germination parameters, shoot and root length, shoot and root fresh and dry weights of some forage sorghum cultivars (Kandil et al., 2012). Therefore, in the present investigation three forage range legumes namely centro, clitoria and siratro were tested for their relative salt tolerance to increasing levels of salinity in those combinations of salts which nearly exist in the natural salt affected soils

Pathways to Achieve National Ambient Air Quality Standards (NAAQS) in India

The rapid economic growth and steep population increase in India’s urban areas, and the lack of policy measures to control pollution in these regions, are causing public health problems, significant environmental degradation, including of air, water, and land, and increased production of greenhouse gases. Together, these undermine the potential for sustainable socio-economic development of the country, and will particularly have severe implications for the poor. A large share of the Indian population is exposed to pollution levels that do not conform to global and national air quality standards. Globally, Indian cities rank poorly in terms of air pollution. Numerous monitoring sites across India report high concentrations of PM2.5, which exceed the benchmark limit (of 40 μg/m³) suggested by the National Ambient Air Quality Standards (NAAQS). It is estimated that in 2015, more than half the Indian population—about 670 million people—were exposed to ambient PM2.5 concentrations that do not comply with India’s NAAQS. Further, less than one per cent enjoyed air quality that met the global World Health Organization (WHO) benchmark limit of 10 μg/m³. About one-quarter of the population lived in areas where the WHO guideline was exceeded by more than nine times. Exposure to air pollution poses a serious health burden in India. Available health impact assessments suggest that several hundred thousand cases of premature deaths annually are attributable to pollution

EMT transcription factors snail and slug directly contribute to cisplatin resistance in ovarian cancer

<p>Abstract</p> <p>Background</p> <p>The epithelial to mesenchymal transition (EMT) is a molecular process through which an epithelial cell undergoes transdifferentiation into a mesenchymal phenotype. The role of EMT in embryogenesis is well-characterized and increasing evidence suggests that elements of the transition may be important in other processes, including metastasis and drug resistance in various different cancers.</p> <p>Methods</p> <p>Agilent 4 × 44 K whole human genome arrays and selected reaction monitoring mass spectrometry were used to investigate mRNA and protein expression in A2780 cisplatin sensitive and resistant cell lines. Invasion and migration were assessed using Boyden chamber assays. Gene knockdown of <it>snail </it>and <it>slug </it>was done using targeted siRNA. Clinical relevance of the EMT pathway was assessed in a cohort of primary ovarian tumours using data from Affymetrix GeneChip Human Genome U133 plus 2.0 arrays.</p> <p>Results</p> <p>Morphological and phenotypic hallmarks of EMT were identified in the chemoresistant cells. Subsequent gene expression profiling revealed upregulation of EMT-related transcription factors including <it>snail, slug, twist2 </it>and <it>zeb2</it>. Proteomic analysis demonstrated up regulation of Snail and Slug as well as the mesenchymal marker Vimentin, and down regulation of E-cadherin, an epithelial marker. By reducing expression of <it>snail </it>and <it>slug</it>, the mesenchymal phenotype was largely reversed and cells were resensitized to cisplatin. Finally, gene expression data from primary tumours mirrored the finding that an EMT-like pathway is activated in resistant tumours relative to sensitive tumours, suggesting that the involvement of this transition may not be limited to <it>in vitro </it>drug effects.</p> <p>Conclusions</p> <p>This work strongly suggests that genes associated with EMT may play a significant role in cisplatin resistance in ovarian cancer, therefore potentially leading to the development of predictive biomarkers of drug response or novel therapeutic strategies for overcoming drug resistance.</p

Grambank reveals the importance of genealogical constraints on linguistic diversity and highlights the impact of language loss

While global patterns of human genetic diversity are increasingly well characterized, the diversity of human languages remains less systematically described. Here we outline the Grambank database. With over 400,000 data points and 2,400 languages, Grambank is the largest comparative grammatical database available. The comprehensiveness of Grambank allows us to quantify the relative effects of genealogical inheritance and geographic proximity on the structural diversity of the world's languages, evaluate constraints on linguistic diversity, and identify the world's most unusual languages. An analysis of the consequences of language loss reveals that the reduction in diversity will be strikingly uneven across the major linguistic regions of the world. Without sustained efforts to document and revitalize endangered languages, our linguistic window into human history, cognition and culture will be seriously fragmented.Genealogy versus geography Constraints on grammar Unusual languages Language loss Conclusio