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Seasonal variations in nitrogen (N2 ) fixation and denitrification rates were estimated in the sediment of Sundarban mangrove ecosystem, India. The mean rate of microbial N2 fixation (16.53 ηmol N fixed/hr/g dry wt of sediment) was relatively higher than the mean rate of denitrification (14.72 ηmol N2O-N /hr/dry wt of sediment) in the mangrove sediment throughout the study, suggesting satisfactory fertility of this ecoregion in terms of sediment nitrogen. Sediment from the deeper parts of this ecosystem showed higher N2 fixation rate (18.23 ηmol N fixed/hr/g dry wt of sediment) than the surface sediment (10.17 ηmol N fixed/hr/g dry wt of sediment). Similar trend was observed for the denitrification rate in all the seasons. The ratio of N2 fixation to denitrification rate showed an increasing trend with depth. The results depicted that under higher anoxic condition bacteria would prefer N2 fixation over denitrification and would ultimately enhance the nitrogen storage capacity of this mangrove ecosystem. Although population of free living N2 fixing bacteria decreased with increase in depth, the rate of N2 fixation showed a reverse trend, during the study period. These results suggested that anoxic condition and low level of nitratenitrogen content could stimulate the enzyme activity responsible for N2 fixation in this particular ecosystem. [ABSTRACT FROM AUTHOR]

Background: The ethnic diversity of India provides a unique opportunity to study the history of the origin of mutations of genetic disorders. Spinocerebellar ataxia type 27B (SCA27B), a recently identified dominantly inherited cerebellar disorder is caused by GAA-repeat expansions in intron 1 of Fibroblast Growth Factor 14 (FGF14). Predominantly reported in the European population, we aimed to screen this mutation and study the founder haplotype of SCA27B in Indian ataxia patients., Methods: We have undertaken screening of GAA repeats in a large Indian cohort of ~ 1400 uncharacterised ataxia patients and kindreds and long-read sequencing-based GAA repeat length assessment. High throughput genotyping-based haplotype analysis was also performed. We utilized ~ 1000 Indian genomes to study the GAA at-risk expansion alleles., Findings: We report a high frequency of 1.83% (n = 23) of SCA27B in the uncharacterized Indian ataxia cohort. We observed several biallelic GAA expansion mutations (n = 5) with younger disease onset. We observed a risk haplotype (AATCCGTGG) flanking the FGF14-GAA locus over a 74 kb region in linkage disequilibrium. We further studied the frequency of this risk haplotype across diverse geographical population groups. The highest prevalence of the risk haplotype was observed in the European population (29.9%) followed by Indians (21.5%). The observed risk haplotype has existed through ~ 1100 generations (~ 22,000 years), assuming a correlated genealogy., Interpretation: This study provides valuable insights into SCA27B and its Upper Paleolithic origin in the Indian subcontinent. The high occurrence of biallelic expansion is probably relevant to the endogamous nature of the Indian population., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Protein Z (PZ), a cofactor for PZ-dependent protease inhibitor, is known to play an important role in inhibiting the coagulation cascade. The aim of the study was to investigate whether PZ G79A polymorphism is a risk factor for puerperal cerebral venous thrombosis (CVT). A total of 71 patients with puerperal CVT and 98 healthy controls were genotyped for PZ 79GA polymorphism by polymerase chain reaction-restriction fragment length polymorphism method. In patients, the genotype distribution for GG, GA, and AA genotypes was 22.5%, 43.7%, and 33.8%, and in controls, 25.5%, 40.8%, and 33.7%, respectively. The risk associated with carrying the mutant genotype (GA and AA) versus the wild GG genotype was found to be 1.11 (95% confidence interval: 0.52-2.35; P = .909). There was no significant difference in the clinical features of the patients with and without the polymorphism. We therefore conclude that PZ G79A polymorphism is not a risk factor for puerperal CVT in Indian women., (© The Author(s) 2014.)

It is unclear whether the somatic JAK2V617F mutation, a marker for chronic myeloproliferative disorders (MPDs), is associated with cerebral venous thrombosis (CVT) in the absence of MPD. Our aim was to determine the prevalence and association of the JAK2V617F mutation among patients with CVT and without overt MPD. We investigated 372 CVT patients without features suggestive of MPD and 383 age- and gender-matched healthy controls, for the JAK2V617F mutation. Genotyping was done by polymerase chain reaction and restriction fragment length polymorphism. The heterozygous JAK2V617F mutation was present in 22 of 372 patients (5.9%) and 2 of 383 controls (0.5%). Logistic regression analysis showed this mutation to be an independent predictor of CVT after adjusting for the conventional risk factors (adjusted odds ratio: 5.47, 95% CI: 1.06-28.27, p=0.04). The mutation was more prevalent in men (p=0.005). Patients with JAK2V617F mutation were older (p=0.036), and had higher mean hemoglobin level (p<0.0001) than those without the mutation. Smokers with the mutation had 9.45-fold increased risk of CVT compared to non-smokers without the mutation (OR: 9.45, 95% CI: 1.17-76.02, p<0.0001). We conclude that the JAK2V617F mutation could contribute to increased risk of CVT in Indians. Larger studies in other ethnic populations are warranted before considering the inclusion of the JAK2V617F gene polymorphism into the routine diagnostic workup of CVT., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The muscles of some important marine fishes collected in and around Hooghly estuarine coastal areas were analyzed for the heavy metals Cu, Zn, Ni, Cd, Cr and Pb. The concentration range of Cu (16.22-47.97 ppm), Pb (12.40-19.96 ppm) and Zn (12.13-44.74 ppm) were recorded comparatively higher and were similar to that found in contaminated areas. On the other hand the ranges of Ni (2.20-3.69 ppm), Cr (0-3.89 ppm) and Cd (0.62-1.20 ppm) were almost equal to those carried out over a wide range of geographical areas. The degree of bioaccumulations was metal-specific as well as species-specific in nature. The toxic groups of metals (Pb and Cd) showed higher variability than the essential metals (Cu, Zn and Ni). The calculated intake value of metals (week⁻¹ kg⁻¹ body wt) varied from 14.88 to 27.60 of Pb, 0.87 to 1.68 of Cd, 0.0 to 5.45 of Cr, 22.70 to 137.16 of Cu, 3.08 to 5.17 of Ni and 16.98 to 62.60 of Zn through human consumption of these fishes and were compared with those of standard Provisional Tolerable Weekly Intake value (PTWI) per kg body weight as stipulated by WHO. The PTWI(Cal) values of Pb in some of the fishes recorded marginally excess values and may indicate a health risk through consumption of successive 7 days in a week.

Objectives: Tandem mass spectrometry is a major technological advance in the screening for inborn errors of metabolism. It has the advantage of sensitive and simultaneous multiple disease screening with minimal sample requirement. The diseases detected include aminoacidemias, fatty acid oxidation disorders, and organic acidemias., Design and Methods: Using automated electrospray tandem mass spectrometry we screened 3550, clinically selected, symptomatic children for inborn errors of metabolism by analyzing amino acids and acylcarnitines in dried blood filter-paper samples., Results: Among these, 113 (3.2%) children were identified with a metabolic disorder: 61 (54%) patients had amino acid disorders, 47 (41.6%) had organic acidemias, and 5 (4.4%) children had disorders of fatty acid oxidation. The diagnoses were further confirmed through clinical symptoms, and other biochemical studies., Conclusions: These results show that inherited metabolic disorders are not rare in India, a rapidly developing country with a high birth rate and relatively frequent occurrence of consanguineous marriages., (Copyright 2009 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

An aprotinin sensitive serine protease was identified in the culture supernatant of the Indian strain of Leishmania donovani (MHOM/IN/1983/AG83). The protease was subsequently purified and characterized. The apparent molecular mass of the enzyme was 115 kDa in SDS-PAGE under non-reducing condition, while on reduction it showed a 56 kDa protein band indicating that the protease is a dimeric protein. The purified enzyme was optimally active at the pH and temperature of 7.5 and 28 degrees C, respectively. Assays of thermal stability indicated that the enzyme preserved 59% of activity even after pretreatment at 42 degrees C for 1 h. The purified protease was not glycosylated and its isoelectric pI was 5.0. N-alpha-p-tosyl-L-arginine methylester (TAME) appeared to be relatively better substrate among the commonly used synthetic substrates. The enzyme was inhibited by Ca(2+) and Mn(2+), but activated by Zn(2+). The protease could play important role(s) in the pathogenesis of visceral leishmaniasis or kala-azar.

Monthly variation of CO2 fugacity (fCO2) in surface water and related atmospheric exchanges were measured in the Hooghly estuary which is one of the most important estuaries, since it is fed by one of the world's largest rivers, the Ganges with a flow of 15,646 m3 s-1 (1.6% of the world's combined river flow). Carbon dioxide fluxes averaged over the entire estuary are in the range of -2.78 to 84.4 mmol m-2 d-1. This estuary acts as a sink for CO2 during monsoon months and seasonal variation of its flux is controlled by dilution of seawater by river water. Since the solubility of CO2 and the disassociation of carbonic acid in estuarine water are controlled by temperature and salinity, the observed variations of CO2 fluxes are compared with those predicted from seasonal changes in temperature, salinity and the ratio of gross primary production to community respiration using empirical equations with an explained variability of 55%.