A quantitative analysis of germ cells and the histone variants in the testes of vitamin A-deficient rats and during subsequent repletion with vitamin A

A quantitative analysis of the different types of germ cells present in the seminiferous tubules of vitamin A-deficient-retinoate maintained rats revealed that the number of pachytene spermatocytes and spermatogonia was greatly reduced in the deficient rats. Spermatids were virtually absent in the deficient tubules which contained mostly spermatogonia and preleptotene spermatocytes along with the Sertoli cells. There was no change in the number of Sertoli cells present in the tubules of deficient rats as compared to that of normal rats. Following supplementation of retinyl acetate to vitamin A-deficient-retinoate maintained rats, there was an immediate thinning of the germinal epithelium resulting from the sloughing off of the damaged spermatocytes which were beyond repair. However, after 12 days of vitamin A supplementation fresh batch of pachytene spermatocytes started appearing while by day 16 round spermatids could be seen. Analysis of the acid soluble proteins from nuclei on different types of Polyacrylamide gel electrophoretic systems has revealed that the levels of the testis specific histone variants Hlt, TH2A and TH2B, synthesized predominantly in the pachytene spermatocytes were greatly reduced in the testes of retinoate maintained rats. Following supplementation of retinyl acetate for either 4 days or 8 days the levels of these histone variants further decreased which correlated with the decrease in the number of pachytene spermatocytes. However, by day 12 of supplementation onwards, their levels started increasing and reached near normal levels by day 24 of vitamin A-supplementation

Developing procedures for assessment of ecological status of Indian River basins in the context of environmental water requirements

River basins / Ecology / Indicators / Environmental flows / Environmental management / Habitats / Biota / Fish / Ecosystems / India / Krishna River Basin / Chauvery River Basin / Narmada River Basin / Periyar River Basin / Ganga River Basin

Experimental investigation of bifurcations in a thermoacoustic engine

In this study, variation in the characteristics of the pressure oscillations in a thermoacoustic engine is explored as the input heat flux is varied. A bifurcation diagram is plotted to study the variation in the qualitative behavior of the acoustic oscillations as the input heat flux changes. At a critical input heat flux (60 Watt), the engine begins to produce acoustic oscillations in its fundamental longitudinal mode. As the input heat flux is increased, incommensurate frequencies appear in the power spectrum. The simultaneous presence of incommensurate frequencies results in quasiperiodic oscillations. On further increase of heat flux, the fundamental mode disappears and second mode oscillations are observed. These bifurcations in the characteristics of the pressure oscillations are the result of nonlinear interaction between multiple modes present in the thermoacoustic engine. Hysteresis in the bifurcation diagram suggests that the bifurcation is subcritical. Further, the qualitative analysis of different dynamic regimes is performed using nonlinear time series analysis. The physical reason for the observed nonlinear behavior is discussed. Suggestions to avert the variations in qualitative behavior of the pressure oscillations in thermoacoustic engines are also provided

Alpha 1 antitrypsin gene: A case-control study in chronic obstructive pulmonary disease

Alpha-1 antitrypsin (AAT) deficiency is an inherited disorder that causes low levels of, or no AAT in the blood. The most common illness in adults with AAT deficiency is lung disease during the third and fourth decades of life. Most commonly, it is associated with chronic obstructive pulmonary disease (COPD). Mutations in the protease inhibitor (PI) gene, located on chromosome 14, are associated with this genetic disorder. The Z protein is due to a single amino acid substitution of 342 glutamine lysine. Although cigarette smoking is the main environmental risk factor, only about 15% of smokers develop clinically significant disease suggesting other influences on disease expression. The study included hospital based age and sex matched 100 cases of COPD and 100 controls without COPD recruited from Christian Medical Centre, Jorhat, Assam. These cases were recruited from February 2009 to December 2009. Subjects were included in the COPD group on the basis of lung function test. DNA extraction was done by DNA extraction kit and amplification for AAT gene was done by site directed mutagenesis polymerase chain reaction (PCR) method as described by Tazellar et al. (1992). We found that smoking was the prior cause of COPD. A1AT deficiency is not prevalent in our population subset but certain other genes could be the attributable factor for COPD.Key words: Alpha 1-antitrypsin, chronic obstructive pulmonary disorder (COPD)

Lung function decline: a cohot study in a population exposed to coal dust

Chronic Obstructive Pulmonary Disease (COPD), is characterized by coughing, shortness of breath, sputum production, rapid breathing, wheezing, and weight loss due to the energy required for labored breathing. COPD includes chronic bronchitis and emphysema chronic bronchitis inflammation of the lining of the bronchial tubes emphysema permanent destruction of the alveoli. Chronic respiratory diseases have a preeminent role in the health conditions of people residing near coalmine areas with implications for morbidity and excess mortality from specific causes. Atmospheric pollution from anthropogenic sources such as coal mining, industrial sources is a serious worldwide concern as it is associated with adverse health effects.The aim of this study was to find a correlation between coal dust and reductions in lung function. An environmental health survey was conducted in and around the surrounding areas of opencast coal mine, Tirap to determine the prevalence of various respiratory symptoms and to assess pulmonary function among the villagers. Although cigarette smoking is the main environmental risk factor, only about 15% of smokers develop clinically significant disease suggesting other influences on disease expression. We screened 412 individuals during surveys at the coal mine site, Assam to find out possible occurrences of COPD and associated environmental risk factors, mainly coal dust exposure. Lung function test was done with a portable spirometer. COPD was diagnosed on the basis ATS guidelines. The subjects were categorized into COPD (Smokers and NonSmokers) and NonCOPD (Smokers and NonSmokers). Air quality was monitored using Respirable Dust Sampler and analyzed for Respirable Suspended Particulate Matter (RSPM), SO2 and NO2.Coal dust exposure was a potential factor in development of COP

Strong decline in female sterilization rates in Norway after the introduction of a new copayment system: a registry based study

<p>Abstract</p> <p>Background</p> <p>January 1, 2002, copayment for outpatient female sterilization in Norwegian public hospitals increased from 33 euros to 750 euros after a revision of the health care system. The aim of the present study was to investigate the effect of the new copayment system on female sterilization epidemiology.</p> <p>Methods</p> <p>We retrieved data on all female sterilizations 1999–2005 (N = 23 1333) from the Norwegian Patient Register, an administrative register to which it is mandatory for all hospitals to report. Sterilizations with diagnostic codes indicative of vaginal delivery, caesarean section, spontaneous abortion, ectopic pregnancy, and termination of pregnancy were analyzed separately. All other sterilizations were defined as "interval sterilization".</p> <p>Results</p> <p>An abrupt fall in female sterilization was observed after the raise in copayment. Age-adjusted incidence rates dropped from 6.3–6.8 per 1000 women in 1999–2001 to 2.2–2.3 per 1000 women during 2002–2005. Interval sterilizations dropped to 25% of the previous level after the rise in copayment while sterilizations in conjunction with caesarean section and postpartum sterilization remained constant.</p> <p>Conclusion</p> <p>For many Norwegian women seeking contraception, sterilization is no longer an available alternative.</p

Mapping the cellular landscape of Atlantic salmon head kidney by single cell and single nucleus transcriptomics

Single-cell transcriptomics is the current gold standard for global gene expression profiling, not only in mammals and model species, but also in non-model fish species. This is a rapidly expanding field, creating a deeper understanding of tissue heterogeneity and the distinct functions of individual cells, making it possible to explore the complexities of immunology and gene expression on a highly resolved level. In this study, we compared two single cell transcriptomic approaches to investigate cellular heterogeneity within the head kidney of healthy farmed Atlantic salmon (Salmo salar). We compared 14,149 cell transcriptomes assayed by single cell RNA-seq (scRNA-seq) with 18,067 nuclei transcriptomes captured by single nucleus RNA-Seq (snRNA-seq). Both approaches detected eight major cell populations in common: granulocytes, heamatopoietic stem cells, erythrocytes, mononuclear phagocytes, thrombocytes, B cells, NK-like cells, and T cells. Four additional cell types, endothelial, epithelial, interrenal, and mesenchymal cells, were detected in the snRNA-seq dataset, but appeared to be lost during preparation of the single cell suspension submitted for scRNA-seq library generation. We identified additional heterogeneity and subpopulations within the B cells, T cells, and endothelial cells, and revealed developmental trajectories of heamatopoietic stem cells into differentiated granulocyte and mononuclear phagocyte populations. Gene expression profiles of B cell subtypes revealed distinct IgM and IgT-skewed resting B cell lineages and provided insights into the regulation of B cell lymphopoiesis. The analysis revealed eleven T cell sub-populations, displaying a level of T cell heterogeneity in salmon head kidney comparable to that observed in mammals, including distinct subsets of cd4/cd8-negative T cells, such as tcrγ positive, progenitor-like, and cytotoxic cells. Although snRNA-seq and scRNA-seq were both useful to resolve cell type-specific expression in the Atlantic salmon head kidney, the snRNA-seq pipeline was overall more robust in identifying several cell types and subpopulations. While scRNA-seq displayed higher levels of ribosomal and mitochondrial genes, snRNA-seq captured more transcription factor genes. However, only scRNA-seq-generated data was useful for cell trajectory inference within the myeloid lineage. In conclusion, this study systematically outlines the relative merits of scRNA-seq and snRNA-seq in Atlantic salmon, enhances understanding of teleost immune cell lineages, and provides a comprehensive list of markers for identifying major cell populations in the head kidney with significant immune relevance.</p

Mapping the cellular landscape of Atlantic salmon head kidney by single cell and single nucleus transcriptomics

The study was funded by grants from the Research Council Norway (ID:302191), the University of Edinburgh's Data Driven Innovation Initiative (Scottish Funding Council Beacon ‘Building Back Better’ Call), and the Biotechnology and Biological Sciences Research Council, including the institutional strategic programme grants BBS/E/D/10002071, BBS/E/RL/230001C, BBS/E/D/20002174, BBS/E/RL/230002B, and the responsive mode grants BB/W005859/1 and BB/W008564/1. NH is supported by a Wellcome Trust Senior Research Fellowship in Clinical Science (ref. 219542/Z/19/Z). UG is supported by the Research Council of Norway (ID:274635).Peer reviewe

Operando Laboratory-Based Multi-Edge X-Ray Absorption Near-Edge Spectroscopy of Solid Catalysts

Laboratory-based X-ray absorption spectroscopy (XAS) and especially X-ray absorption near-edge structure (XANES) offers new opportunities in catalyst characterization and presents not only an alternative, but also a complementary approach to precious beamtime at synchrotron facilities. We successfully designed a laboratory-based setup for performing operando , quasi-simultaneous XANES analysis at multiple K edges, more specifically, operando XANES of mono-, bi-, and trimetallic CO 2 hydrogenation catalysts containing Ni, Fe, and Cu. Detailed operando XANES studies of the multi-element solid catalysts revealed metal-dependent differences in the reducibility and re-oxidation behavior and their influence on the catalytic performance in CO 2 hydrogenation. The applicability of operando laboratory-based XANES at multiple K edges paves the way for advanced multi-element catalyst characterization complementing detailed studies at synchrotron facilities.Peer reviewe