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771.
Chaitanya Kumar Jha Dhara Patel Narayanan Rajendran Meenu Saraf 《Journal of basic microbiology》2010,50(3):211-217
The extensive and enduring challenges in soil microbiology depend on the development of efficient methods to be acquainted with the types of microbes present in soil, and to determine the functional performance of the overall microbial groups in situ. This study aims to investigate the combined uses of species richness and diversity as well as to estimate the combinatorial effect of species richness and diversity in order to understand their role and distribution in their habitat. To achieve this objective a study was designed targeting the rhizosphere of Jatropha curcas L. which were planted in various soil conditions on five distinctive sites of Gujarat state (India). These sites were constantly monitored and studied for the species richness and evenness (“heterogeneity”). The isolates were checked for their PGPR potentials like Phosphate solubilisation, Siderophore production, Indole acetic acid production, ACC deaminase production, HCN production, EPS production and Ammonia production. The results obtained were used to calculate richness, evenness and diversity indices. Results reveal the total heterogeneity in the site of fertile Jatropha rhizosphere (GS4) as well as sodic soil site (GS5) than other three sites. Absence of equitability under the selected and defined condition was also observed in GS4 and GS5 sites. The combinatorial estimates provide the information on their distribution and roles in the habitat. In particular, such an empirical relationship from a single rhizosphere of a distinctive species Jatropha is useful to test diversity predictions in natural sites, and further it can be applied to either by performing trials over larger spatial and temporal scales or by conducting correlational studies of biodiversity gradients. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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774.
Jobin Jose Kattoor Yashpal Singh Malik Sharad Saurabh Shubhankar Sircar Obli Rajendran Vinodhkumar Durlav Prasad Bora Kuldeep Dhama Souvik Ghosh Krisztian Banyai Nadia Touil Ahmed S. Abdel‐Moneim Anastasia N. Vlasova Nobumichi Kobayashi Raj Kumar Singh 《Transboundary and Emerging Diseases》2019,66(1):47-53
Porcine astroviruses (PAstVs) have extended their distribution globally and have a high prevalence; however, their clinical significance is still under investigation. Thus far, information about their prevalence and diversity in the Indian pig population is unknown. This study is the first report on the prevalence and genetic characterization of PAstVs in diarrhoeic piglets in India. From January 2013 to December 2017, 757 samples were screened using an RT‐PCR assay and PAstV infection was detected in 17.6% (133/757) pigs. Of the 133 positive samples, 79 (59.4%) were positive for PAstV alone, whereas 54 (40.6%) were found to be co‐infected with porcine rotavirus A (PoRVA). Phylogenetic analysis of RdRp/capsid gene region revealed high genetic heterogeneity among PAstV sequences, with a predominance of PAstV lineage 4 and detection of lineage 2. The lineage 4 PAstVs exhibited 61.2%–94.5% sequence similarity at the nucleotide level to other reported sequences, whereas lineage 2 strain shared 66.0%–71.6% sequence identity with cognate sequences of the same lineage. This is the first report on PAstV and circulation of lineages 4 and 2 in India. Further, phylogenetic analysis indicates a multiphyletic origin of PAstV strains and suggests cross‐border circulation of PAstVs with a similar genetic configuration in Asian countries. 相似文献
775.
PURPOSE: To compare the anterior segment parameters in photopic and scotopic conditions using anterior segment optical coherence tomography (AS OCT) in Indian eyes. MATERIALS AND METHODS: One hundred eyes of 100 normal subjects of both sexes, aged 19 to 76 years, underwent anterior segment evaluation by AS OCT (Visante OCT). Central corneal thickness (CCT), central anterior chamber depth (ACD), pupil diameter (PD) and the temporal and nasal peripheral irido-corneal angles were assessed in photopic and scotopic conditions. These anterior segment parameters were stratified for age, sex and refractive error. RESULTS: Mean values of the parameters measured in photopic and scotopic conditions respectively were as follows: ACD (mm) 2.88 +/- 0.32, 2.89 +/- 0.32 (P = 0.10); nasal angle (degrees) 28.80 +/- 5.91, 22.28 +/- 7.50 (P < 0.001); temporal angle (degrees) 29.95 +/- 6.74, 22.82 +/- 8.43 (P < 0.001); pupil diameter (mm) 4.08 +/- 0.91, 4.68 +/- 0.92 (P < 0.001); CCT (microm) 519 +/- 33.88, 519 +/- 33.88. CONCLUSIONS: There was no significant difference in the ACD in photopic and scotopic conditions. While the nasal and temporal angles showed a significant decrease, the pupil diameter showed a significant increase in scotopic conditions. Mean central ACD decreased with age and was shallower in females than in males. It was highest in myopes and lowest in hypermetropes. CCT was not influenced by photopic and scotopic conditions. 相似文献
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777.
Dhira Rani Saha Simanti Datta Santanu Chattopadhyay Rajashree Patra Ronita De Krishnan Rajendran Abhijit Chowdhury Thandavaryan Ramamurthy Asish Kumar Mukhopadhyay 《World journal of gastroenterology : WJG》2009,15(9):1105-1112
AIM: To investigate the changing pattern of different histological parameters occurring in the stomach tissue of Helicobacter pylori (H pylori) infected tribal populations and duodenal ulcer patients among ethnic Bengalis and correlation of the genotypes of H pylori with different histological parameters. METHODS: One hundred and twelve adult individuals were enrolled into this study between 2002 and 2004. Among them, 72 had clinical features of duodenal ulcer (DU) from ethnic Bengali population and 40 were asymptomatic ethnic tribals. Endoscopic gastric biopsy samples were processed for histology, genotyping and rapid urease test. Histologically, haematoxylin and eosin staining was applied to assess the pathomorphological changes and a modified Giemsa staining was used for better detection of Hpylori. For intestinal metaplasia, special stainings, i.e. Alcian blue periodic acid-Schiff and high iron diamine-Alcian blue staining, were performed. PCR was performed on bacterial DNA to characterize the presence or absence of virulence-associated genes, like cagA, and distribution of different alleles of vacA and iceA. RESULTS: Intraglandular neutrophil infiltration, a hallmark of activity of gastritis, was present in 34 (94%) of tribals (TRs) and 42 (84%) of DU individuals infected with H pylori. Lymphoid follicles and aggregates, which are important landmarks in H pylori infection, were positive amongst 15 (41%) of TRs and 20 (40%) of DU subjects. Atrophic changes were observed in 60% and 27.7%, respectively, among DU cases and tribals (P 〉 0.003). Metaplastic changes were detected in low numbers in both groups. Moderate to severe density distribution of Hpylori in the gastric mucosa was 63% among TRs, whereas it was 62% in DU subjects. There were no significant differences in the distribution of virulence-associated genes like cagA, vacA and iceA of H pylori strains carried by these two populations. CONCLUSION: Our study showed almost similar distribution of inflammatory cells among asymptomatic tribals and DU Bengali patients. Interestingly, the tribal population are free from any clinical symptoms despite evidence of active histologic gastritis and infection with Hpylori strains carrying similar virulence markers as of strains isolated from patients with DU. There was an increased cellular response, especially in terms of neutrophil infiltration, but much lower risk of developing atrophy and metaplastic changes among the tribal population. 相似文献
778.
Shukla D Rajendran A Gibbs D Suganthalakshmi B Zhang K Sundaresan P 《American journal of ophthalmology》2007,144(3):419-423
PURPOSE: To describe the unusual clinical manifestations and diagnostic evaluation of X-linked retinoschisis (XLR). DESIGN: Prospective, observational case series. METHODS: Eight patients with subnormal vision seeking treatment at a tertiary eye care center were evaluated clinically by optical coherence tomography (OCT) and electroretinography (ERG) in this prospective, noncomparative case series. Mutational screening was performed for the retinoschisin gene (RS1) by direct deoxyribonucleic acid (DNA) sequencing. The primary outcome measures were the clinical fundus findings and genetic results. RESULTS: The mean patient age was 16.4 years (range, two to 33 years). Family history was positive in seven patients. Four demonstrated atypical fundus findings of XLR bilaterally. Atypical features included macular dragging and distortion (seven eyes, five patients), macular pigmentary changes or scarring (five eyes; three patients), and bilateral exudative detachments (one patient). One patient had macular dragging and pigmentary changes bilaterally. ERG aided diagnosis in five patients: selective B-wave suppression was observed in all. OCT demonstrated typical retinal schitic cavities universally, including the eyes with macular dragging and scarring. Genetic studies confirmed the clinical diagnosis in all patients; two revealed novel mutations. CONCLUSIONS: We identified unusual presentations of XLR with the help of ERG, OCT, family screening, and genetic analysis; OCT seems to be a consistent diagnostic aid across the clinical spectrum of XLR. 相似文献
779.
Thenmozhi V Hiriyan JG Tewari SC Philip Samuel P Paramasivan R Rajendran R Mani TR Tyagi BK 《Japanese journal of infectious diseases》2007,60(5):245-249
The natural occurrence of vertical transmission of dengue viruses in Aedes albopictus (Skuse) mosquitoes was examined in the state of Kerala in southern India. Adults and larvae of Ae. albopictus collected from Kerala were screened for dengue viruses by using enzyme-linked immunosorbent assay with dengue-specific monoclonal antibodies. The possibility of the vertical transmission of dengue virus in Ae. albopictus was further evidenced by the detection of the virus in field-collected adult males as well as females emerged from field-collected larvae. Two pools, one pool from the adult males and one pool from the emerged females derived from field-collected larvae, were collected in the relatively hot months of June and March, respectively, and found to be positive for dengue virus antigen. Dengue serotype 2 virus was isolated from field-collected male adults in Kerala. These findings suggest that dengue virus is maintained in Ae. albopictus mosquitoes during the dry season by vertical transmission in nature. 相似文献
780.
Overexpression of CCS in G93A-SOD1 mice leads to accelerated neurological deficits with severe mitochondrial pathology 总被引:1,自引:0,他引:1
Son M Puttaparthi K Kawamata H Rajendran B Boyer PJ Manfredi G Elliott JL 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(14):6072-6077
Cu, Zn superoxide dismutase (SOD1) has been detected within spinal cord mitochondria of mutant SOD1 transgenic mice, a model of familial ALS. The copper chaperone for SOD1 (CCS) provides SOD1 with copper, facilitates the conversion of immature apo-SOD1 to a mature holoform, and influences in yeast the cytosolic/mitochondrial partitioning of SOD1. To determine how CCS affects G93A-SOD1-induced disease, we generated transgenic mice overexpressing CCS and crossed them to G93A-SOD1 or wild-type SOD1 transgenic mice. Both CCS transgenic mice and CCS/wild-type-SOD1 dual transgenic mice are neurologically normal. In contrast, CCS/G93A-SOD1 dual transgenic mice develop accelerated neurological deficits, with a mean survival of 36 days, compared with 242 days for G93A-SOD1 mice. Immuno-EM and subcellular fractionation studies on the spinal cord show that G93A-SOD1 is enriched within mitochondria in the presence of CCS overexpression. Our results indicate that CCS overexpression in G93A-SOD1 mice produces severe mitochondrial pathology and accelerates disease course. 相似文献