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71.
Aruliah Rajasekar Thambidurai Ganesh Babu Sundaram Maruthamuthu Shunmugiah Thevar Karutha Pandian Sidhan Mohanan Narayanan Palaniswamy 《World journal of microbiology & biotechnology》2007,23(8):1065-1074
A facultative anaerobic species Serratia marcescens ACE2 isolated from the corrosion products of a diesel-transporting pipeline in North West India was identified by 16S rDNA
sequence analysis. The role of Serratia marcesens ACE2 on biodegradation of commercial corrosion inhibitor (CCI) and its influence on the corrosion of API 5LX steel has been
enlightened. The degrading strain ACE2 is involved in the process of corrosion of steel API 5LX and also utilizes the inhibitor
as organic source. The quantitative biodegradation efficiency of corrosion inhibitor was 58%, which was calculated by gas
chromatography mass spectrum analysis. The effect of CCI on the growth of bacteria and its corrosion inhibition efficiency
were investigated. Additionally, the role of this bacterium in corrosion of steel has been investigated by powder X-ray diffractometer
(XRD) and scanning electron microscope studies. The presence of high-intensity ferric oxides and manganese oxides noticed
from the XRD indicates that ACE2 enhances the corrosion process in presence of inhibitor as a carbon source. This basic study
will be useful for the development of new approaches for the detection, monitoring and control of microbial corrosion in petroleum
product pipelines. 相似文献
72.
The phylogeny and evolution of host choice in the Hippoboscoidea (Diptera) as reconstructed using four molecular markers 总被引:1,自引:0,他引:1
Hippoboscoidea is a superfamily of Diptera that contains the Glossinidae or tsetse flies, the Hippoboscidae or louse flies, and two families of bat flies, the Streblidae and the Nycteribiidae. We reconstruct the phylogenetic relationships within Hippoboscoidea using maximum parsimony and Bayesian methods based on nucleotide sequences from fragments of four genes: nuclear 28S ribosomal DNA and the CPSase domain of CAD, and mitochondrial 16S rDNA and cytochrome oxidase I. We recover monophyly for most of the presently recognized groups within Hippoboscoidea including the superfamily as a whole, the Hippoboscidae, the Nycteribiidae, the bat flies, and the Pupipara (=Hippoboscidae+Nycteribiidae+Streblidae), as well as several subfamilies within the constituent families. Streblidae appear to be paraphyletic. Our phylogenetic hypothesis is well supported and decisive in that most competing topological hypotheses for the Hippoboscoidea require significantly longer trees. We confirm a single shift from a free-living fly to a blood-feeding ectoparasite of vertebrates and demonstrate that at least two host shifts from mammals to birds have occurred. Wings have been repeatedly lost, but never regained. The hippoboscoid ancestor also evolved adenotrophic viviparity and our cladogram is consistent with a gradual reduction in the motility of the deposited final instar larvae from active burrowing in the soil to true pupiparity where adult females glue the puparium within the confines of bat roosts. 相似文献
73.
Parthasarathy NJ Srikumar R Manikandan S Narayanan GS Devi RS 《Cell biology and toxicology》2007,23(3):177-187
Our previous studies revealed that methanol intoxication significantly altered the non-specific immune functions in albino rats. The present investigation focuses on the effect of methanol on certain specific immune functions of cell mediated immunity such as footpad thickness, leukocyte migration inhibition test (LMI) and antibody levels. In addition, serum interleukins (IL-2, IL-4, TNF-alpha and IFN-gamma), and splenic lymphocyte subsets were measured after an immune challenge. The specific immune function tests were carried out in three different groups of albino rats, which include control, 15 and 30 days methanol intoxication. Our study reports that animal body weight, organ weight ratio, lymphoid cell counts, footpad thickness, antibody titer, IL-2, TNF-alpha, IFN-gamma, Pan T cell, CD4, macrophages, MHC class II molecule expression, and B cell counts were significantly decreased compared to control animals nevertheless, LMI, IL-4, and DNA single strand breakage were increased significantly. Plasma corticosterone level was significantly increased in the 15 days group whereas the 30 days methanol intoxication group showed considerable decrease in corticosterone level compared with control animals. Therefore, our investigation concluded that repeated exposure of methanol profoundly suppressed the cell mediated and humoral immune functions in albino rats. 相似文献
74.
Narayanan Jothikumar Bonnie J. Mull Sara V. Brant Eric S. Loker Jeremy Collinson W. Evan Secor Vincent R. Hill 《Applied and environmental microbiology》2015,81(12):4207-4215
Cercarial dermatitis, also known as swimmer''s itch, is an allergenic skin reaction followed by intense itching caused by schistosome cercariae penetrating human skin. Cercarial dermatitis outbreaks occur globally and are frequently associated with freshwater lakes and are occasionally associated with marine or estuarine waters where birds reside year-round or where migratory birds reside. In this study, a broadly reactive TaqMan assay targeting 18S rRNA gene (ribosomal DNA [rDNA]) sequences that was based on a genetically diverse panel of schistosome isolates representing 13 genera and 20 species (the 18S rDNA TaqMan assay) was developed. A PCR assay was also developed to amplify a 28S rDNA region for subsequent sequencing to identify schistosomes. When applied to surface water samples seeded with Schistosoma mansoni cercariae, the 18S rDNA TaqMan assay enabled detection at a level of 5 S. mansoni cercariae in 100 liters of lake water. The 18S rDNA TaqMan and 28S rDNA PCR sequencing assays were also applied to 100-liter water samples collected from lakes in Nebraska and Wisconsin where there were reported dermatitis outbreaks. Avian schistosome DNA was detected in 11 of 34 lake water samples using the TaqMan assay. Further 28S rDNA sequence analysis of positive samples confirmed the presence of avian schistosome DNA and provided a preliminary identification of the avian schistosomes in 10 of the 11 samples. These data indicate that the broadly schistosome-reactive TaqMan assay can be effective for rapid screening of large-volume water samples for detection of avian schistosomes, thereby facilitating timely response actions to mitigate or prevent dermatitis outbreaks. Additionally, samples positive by the 18S rDNA TaqMan assay can be further assayed using the 28S rDNA sequencing assay to both confirm the presence of schistosomes and contribute to their identification. 相似文献
75.
Network of long-range concerted chemical shift displacements upon ligand binding to human angiogenin
Donald Gagné Chitra Narayanan Nicolas Doucet 《Protein science : a publication of the Protein Society》2015,24(4):525-533
Molecular recognition models of both induced fit and conformational selection rely on coupled networks of flexible residues and/or structural rearrangements to promote protein function. While the atomic details of these motional events still remain elusive, members of the pancreatic ribonuclease superfamily were previously shown to depend on subtle conformational heterogeneity for optimal catalytic function. Human angiogenin, a structural homologue of bovine pancreatic RNase A, induces blood vessel formation and relies on a weak yet functionally mandatory ribonucleolytic activity to promote neovascularization. Here, we use the NMR chemical shift projection analysis (CHESPA) to clarify the mechanism of ligand binding in human angiogenin, further providing information on long-range intramolecular residue networks potentially involved in the function of this enzyme. We identify two main clusters of residue networks displaying correlated linear chemical shift trajectories upon binding of substrate fragments to the purine- and pyrimidine-specific subsites of the catalytic cleft. A large correlated residue network clusters in the region corresponding to the V1 domain, a site generally associated with the angiogenic response and structural stability of the enzyme. Another correlated network (residues 40–42) negatively affects the catalytic activity but also increases the angiogenic activity. 15N-CPMG relaxation dispersion experiments could not reveal the existence of millisecond timescale conformational exchange in this enzyme, a lack of flexibility supported by the very low-binding affinities and catalytic activity of angiogenin. Altogether, the current report potentially highlights the existence of long-range dynamic reorganization of the structure upon distinct subsite binding events in human angiogenin. 相似文献
76.
77.
Mukund A. Prabhu Narayanan Namboodiri Srinivas Prasad BV S.P. Abhilash Anees Thajudeen Kumar V.K. Ajith 《Indian pacing and electrophysiology journal》2015,15(6):286-290
Background
Electrical storm (ES) is a life threatening emergency. There is little data available regarding acute outcome of ES.Aims
The study aimed to analyze the acute outcome of ES, various treatment modalities used, and the factors associated with mortality.Methods
This is a retrospective observational study involving patients admitted with ES at our centre between 1/1/2007 and 31/12/2013.Results
41 patients (mean age 54.61 ± 12.41 years; 86.7% males; mean ejection fraction (EF) 44.51 ± 16.48%) underwent treatment for ES. Hypokalemia (14.63%) and acute coronary syndrome (ACS) (14.63%) were the commonest identifiable triggers. Only 9 (21.95%) patients already had an ICD implanted. Apart from antiarrhythmic drugs (100%), deep sedation (87.8%), mechanical ventilation (24.39%) and neuraxial modulation using left sympathetic cardiac denervation (21.95%) were the common treatment modalities used. Thirty-three (80.49%) patients could be discharged after a mean duration of 14.2 ± 2.31 days. Eight (19.5%) patients died in hospital. The mortality was significantly higher in those with EF < 35% compared to those with a higher EF (8 (42.11% vs 0 (0%), p = 0.03)). There was no significant difference in mortality between those with versus without a structural heart disease (8 (21.1% vs 0 (0%), p = 0.32)). Comparison of mortality an ACS with ES versus ES of other aetiologies (3 (50%) vs 5 (14.29) %, p = 0.076)) showed a trend towards significance.Conclusion
With comprehensive treatment, there is reasonable acute survival rate of ES. Hypokalemia and ACS are the commonest triggers of ES. Patients with low EF and ACS have higher mortality. 相似文献78.
79.
80.
Christopher S Verghis RM Antonisamy B Sowmyanarayanan TV Brahmadathan KN Kang G Cooper BS 《PloS one》2011,6(7):e20604