Reconstructing the demographic history of the Himalayan and adjoining populations

The rugged topography of the Himalayan region has hindered large-scale human migrations, population admixture and assimilation. Such complexity in geographical structure might have facilitated the existence of several small isolated communities in this region. We have genotyped about 850,000 autosomal markers among 35 individuals belonging to the four major populations inhabiting the Himalaya and adjoining regions. In addition, we have genotyped 794 individuals belonging to 16 ethnic groups from the same region, for uniparental (mitochondrial and Y chromosomal DNA) markers. Our results in the light of various statistical analyses suggest a closer link of the Himalayan and adjoining populations to East Asia than their immediate geographical neighbours in South Asia. Allele frequency-based analyses likely support the existence of a specific ancestry component in the Himalayan and adjoining populations. The admixture time estimate suggests a recent westward migration of populations living to the East of the Himalaya. Furthermore, the uniparental marker analysis among the Himalayan and adjoining populations reveal the presence of East, Southeast and South Asian genetic signatures. Interestingly, we observed an antagonistic association of Y chromosomal haplogroups O3 and D clines with the longitudinal distance. Thus, we summarise that studying the Himalayan and adjoining populations is essential for a comprehensive reconstruction of the human evolutionary and ethnolinguistic history of eastern Eurasia

Mechanical and electrical properties of multiwall carbon nanotube/polycarbonate composites for electrostatic discharge and electromagnetic interference shielding applications

Home-made multiwall carbon nanotubes (MWCNTs) were used as a reinforcing conducting filler for a thermoplastic polymer, polycarbonate (PC) and the mechanical and electrical properties of the composites were investigated for electrostatic discharge (ESD) and electromagnetic interference (EMI) shielding applications. A uniformly dispersed MWCNT/PC composite system was fabricated using solvent casting and a combination of solvent casting and compression molding techniques. The effect of MWCNTs on the failure mechanism of the polymer under tensile loading showed a ductile to brittle transition with increasing amount of carbon nanotubes. ESD studies showed that the composite films of 2 and 5 wt% functionalized-MWCNT/PC with respective charge decay times of 1 and 0.6 s show promise as electrostatic dissipative materials. EMI shielding effectiveness of a five-layered system (similar to 2 mm thickness) of as-synthesized-MWCNT/PC composite films at 20 wt% loading reached 43 dB in the X-band (8.2-12.4 GHz). The primary mechanism of shielding was absorption, suggesting possible use as an EMI absorbing material. By using low pressure (contact pressure) compression molding the EMI shielding properties of bulk composites (similar to 2 mm thickness) improved by about 14 dB at 10 wt% MWCNT loading

GAPO syndrome in a child without dermal hyaline deposit

A 5-year-old girl with GAPO syndrome from India lacked PAS-positive hyaline material in the skin biopsy from thigh and scalp. The role of this pathological change, earlier reported by Wajntal et al. [1990] in the pathogenesis of GAPO syndrome, needs to be reexamined

Natural History and Endoscopic Management of Pancreaticopleural Fistula: A Tertiary Care Center Experience

Background Pancreaticopleural fistula (PPF) is a rare complication associated with pancreatitis, caused by disruption of the pancreatic duct, either directly or through rupture of a peripancreatic fluid collection, resulting in leakage of pancreatic juice into the pleural space. It commonly presents as massive, relapsing pleural effusions, often on the left side with high amylase content. Nonspecific chest symptoms often predominate, making it a diagnostic challenge. There is a lack of clarity regarding the management of this rare entity

High strain rate behavior of multi-walled carbon nanotubes-polycarbonate composites

Multi-walled carbon nanotubes-polycarbonate composites (MWCNT-PC) were prepared by a two-step method of solvent casting followed by compression molding and their dynamic impact strength was studied. Split Hopkinson Pressure Bar (SHPB) was deployed as the instrument for impact testing of the composite samples. The impact tests were performed under varying strain rates ranging from 1096 to 4017/s. The present studies report the stress-strain behavior of MWCNT-PC composites under a high strain rate of 2000-2600/s. A comparison of stress at various strains ranging from 5% to 20% was done by varying MWCNT concentration in the range 0.1, 0.5, 1, 2 and 5 wt.% in PC. Stress tolerance of these composites was studied to analyze effectiveness of small amounts of carbon nanotubes (CNTs) for impact/stress absorption in comparison to pure PC samples. It was found that the stress behavior for specific strains varies with concentration of CNTs in polycarbonate. At very low (about 0.1 wt.%) and high concentrations (about 5 wt.%) of carbon nanotubes the stress did not vary much as compared to pure PC for the above mentioned strain range. At concentration levels of 0.5, I and 2 wt.% CNTs, the impact absorption (nearly 105 MPa) increased by 10-20% as compared to pure PC (nearly 90 MPa) depending upon the amount of strain in the samples. The role of functionalized CNTs in impact studies was also studied by using 0.5 wt.% and 2 wt.% functionalized MWCNT. The use of functionalized CNTs was found to result in reduced impact absorption (nearly 95 MPa) as compared to as-synthesized CNTs (nearly 105 MPa). The effect of concentration of CNTs on impact strength of MWCNT-PC composites was analyzed by studying the SEM images of composite samples after impact

The paternal ancestry of Uttarakhand does not imitate the classical caste system of India

Although, there have been rigorous research on the Indian caste system by several disciplines, it is still one of the most controversial socioscientific topic. Previous genetic studies on the subcontinent have supported a classical hierarchal sharing of genetic component by various castes of India. In the present study, we have used high-resolution mtDNA and Y chromosomal markers to characterize the genetic structuring of the Uttarakhand populations in the context of neighboring regions. Furthermore, we have tested whether the genetic structuring of caste populations at different social levels of this region, follow the classical chaturvarna system. Interestingly, we found that this region showed a high level of variation for East Eurasian ancestry in both maternal and paternal lines of descent. Moreover, the intrapopulation comparison showed a high level of heterogeneity, likely because of different caste hierarchy, interpolated on asymmetric admixture of populations inhabiting on both sides of the Himalayas

Practice patterns and outcomes with the use of regorafenib in metastatic colorectal cancer: Results from the Regorafenib in Metastatic colorectal cancer - An Indian exploratory analysis study

Background: Regorafenib is considered a standard of care as third-line therapy in metastatic colorectal cancers (mCRCs). Materials and Methods: The study was based on a computerized clinical data form sent to oncologists across the country for entry of anonymized patient data. The data entry form was conceived and generated by the coordinating center's (Tata Memorial Hospital) gastrointestinal medical oncologists and disseminated through personal contacts at academic conferences as well as through E-mail to various oncologists across India. Results: A total of 19 physicians contributed data resulting in 80 patients receiving regorafenib who were available for the evaluation of practice patterns. The median age was 55 years (range: 24–75). Majority had received oxaliplatin-based (97.5%), irinotecan-based (87.5%), and targeted therapy (65%), previously. Patients were primarily started on reduced doses of regorafenib upfront (160 mg – 28.8%, 120 mg – 58.8%, and 80 mg – 12.5%). The median duration of treatment (treatment duration) with regorafenib was 3.1 months (range: 0.5–18), while the median progression free survival was 3.48 months (range: 2.6–4.3). Forty-five percent of patients required dose modifications due to toxicities, and the most common were (all grades) hand-foot syndrome (68.8%), fatigue (46.3%), mucositis (37.6%), and diarrhea (31.3%). Conclusions: Majority of physicians in this collaborative study from India used a lower dose of regorafenib at the outset in patients with mCRC. Despite a lower dose, there was a significant requirement for dose reduction. Duration of treatment with regorafenib as an efficacy end point in this study is similar to available data from other regions as it is the side effect profile