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51.
Lord Wasim Reza Srinath Satyanarayna Donald A. Enarson Ajay M. V. Kumar Karuna Sagili Sujeet Kumar Levi Anand Prabhakar N. M. Devendrappa Ashish Pandey Nevin Wilson Sarabjit Chadha Badri Thapa Kuldeep Singh Sachdeva Mohan P. Kohli 《PloS one》2013,8(10)
Background
Light-emitting diode fluorescence microscopy (LED-FM) has been shown to be more sensitive than conventional bright field microscopy using Ziehl-Neelsen (ZN) stain in detecting sputum smear positive tuberculosis in controlled laboratory conditions. In 2012, Auramine O staining based LED-FM replaced conventional ZN microscopy in 200 designated microscopy centres (DMC) of medical colleges operating in collaboration with India’s Revised National Tuberculosis Control Programme. We aimed to assess the impact of introduction of LED-FM services on sputum smear positive case detection under program conditions.Methods
This was a before and after comparison study. In 15 randomly selected medical college DMCs, all presumptive TB patients who underwent sputum smear examination in the years 2011 (before LED-FM) and 2012 (after LED-FM) were compared. An additional 15 comparable DMCs that implemented conventional ZN sputum smear microscopy were also selected for comparison between 2011 and 2012.Results
The proportion of presumptive TB patients (PTP)found sputum smear positive increased by 30%- from 13.6% (3432/25159) in 2011 to 17.8% (4706/26426) in 2012 (P value <0.01) in the sites that implemented LED-FM microscopy, whereas in DMCs where the ZN staining procedure is followed the proportion of sputum smear positive had remained unchanged (13.0%versus 12.6%;P value0.31).Conclusion
Use of LED-FM significantly increased the proportion of smear positive cases among presumptive TB patients under routine program conditions in high workload laboratories. The study provides operational evidence needed to scale-up the use of LED-FM in similar settings in India and beyond. 相似文献52.
Detection of multiple human papillomavirus (HPV) types in the genital tract is common. Associations among HPV types may impact HPV vaccination modeling and type replacement. The objectives were to determine the distribution of concurrent HPV type infections in cervicovaginal samples and examine type-specific associations. We analyzed HPV genotyping results from 32,245 cervicovaginal specimens collected from women aged 11 to 83 years in the United States from 2001 through 2011. Statistical power was enhanced by combining 6 separate studies. Expected concurrent infection frequencies from a series of permutation models, each with increasing fidelity to the real data, were compared with the observed data. Statistics were computed based on the distributional properties of the randomized data. Concurrent detection occurred more than expected with 0 or ≥3 HPV types and less than expected with 1 and 2 types. Some women bear a disproportionate burden of the HPV type prevalence. Type associations were observed that exceeded multiple hypothesis corrected significance. Multiple HPV types were detected more frequently than expected by chance and associations among particular HPV types were detected. However vaccine-targeted types were not specifically affected, supporting the expectation that current bivalent/quadrivalent HPV vaccination will not result in type replacement with other high-risk types. 相似文献
53.
On the basis of stereo specific information obtained from crystal structures of CDK2, indole and chromene analogues were designed by suitably substituting the pharmacophores on their moiety and docked with target protein for calculating binding affinities. The binding affinities are represented in glide score. (5E)-5-[(1-methyl-1H-indol-3-yl)methylidene]-2,4,6-trioxotetrahydro-2H-pyrimidin-1-ide (I1), (5E)-5-(1H-indol-3-ylmethylidene)-2,4,6-trioxotetrahydro-2H-pyrimidin-1-ide (I2) and 2-amino-4-(4-methyl phenyl)-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile (C9) were selected for synthesis and biological testing based on vital interactions. (5E)-5-(1H-indol-3-ylmethylidene)-2,4,6-trioxotetrahydro-2H-pyrimidin-1-ide(I2) and 2-amino-4-(4-methyl phenyl)-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile (C9) were proved to be active against MCF-7 and HeLa cell lines. 相似文献
54.
Cotton (Gossypium hirsutum L.) is one of the most commercially important fiber crops in the world. Compared with other crops, cotton represents a recalcitrant species for regeneration protocols. The development of efficient and rapid regeneration protocol for elite Indian cotton variety could help improve the quality characteristics and biotic or abiotic stress tolerance. Here we report a novel regeneration protocol in Indian cotton cultivar Narashima. The maximum number of multiple shoots obtained was 16 per explants, performance which has never been achieved in any prior reports. The embryo apex explants were isolated from 2 d old in vitro growing seedlings. Explants were cultured on MS medium containing different plant growth regulator combinations in order to induce multiple shoots. Among the tested combinations, the 2 mg/l of 6-benzylaminopurine (BAP) and 2 mg/l kinetin (KIN) proved to be most suited for achieving the maximum number of multiple shoots. The elongation of multiple shoots was obtained in media supplemented with gibberellic acid (GA3). The regenerated plants were successfully hardened in earthen pots after adequate acclimatization. This method avoids callus tissue, the stage of regeneration which may lead to somaclonal variation. The important feature of the presented method is shortening of regeneration time, as well as the induction of a high number of multiple shoots per explants. The present protocol may provide an efficient and rapid regeneration tool for obtaining more stable transformants from embryo apex explants of Indian cotton cultivar Narashima. 相似文献
55.
To determine the three-dimensional solution structure of the calcium bound S100P protein, the backbone and side chain resonance assignments of the S100P protein have been reported based on triple-resonance experiments using uniformly [13C, 15N]-labeled calcium bound protein. 相似文献
56.
Satish Mohan Gunasekar Palanikumar Asensio Juan A. Agrawal Devendra K. 《Molecular and cellular biochemistry》2020,474(1-2):219-228
Molecular and Cellular Biochemistry - Intracoronary stenting is a common procedure in patients with coronary artery disease (CAD). Stent deployment stretches and denudes the endothelial layer,... 相似文献
57.
Gizem Kalay Joel Atallah Noemie C. Sierra Austin M. Tang Amanda E. Crofton Mohan K. Murugesan Sherri Wykoff-Clary Susan E. Lott 《Evolution; international journal of organic evolution》2020,74(7):1409-1422
Many developmental traits that are critical to the survival of the organism are also robust. These robust traits are resistant to phenotypic change in the face of variation. This presents a challenge to evolution. In this article, we asked whether and how a well-established robust trait, Drosophila segment patterning, changed over the evolutionary history of the genus. We compared segment position scaled to body length at the first-instar larval stage among 12 Drosophila species. We found that relative segment position has changed many times across the phylogeny. Changes were frequent, but primarily small in magnitude. Phylogenetic analysis demonstrated that rates of change in segment position are variable along the Drosophila phylogenetic tree, and that these changes can occur in short evolutionary timescales. Correlation between position shifts of segments decreased as the distance between two segments increased, suggesting local control of segment position. The posterior-most abdominal segment showed the highest magnitude of change on average, had the highest rate of evolution between species, and appeared to be evolving more independently as compared to the rest of the segments. This segment was exceptionally elongated in the cactophilic species in our dataset, raising questions as to whether this change may be adaptive. 相似文献
58.
Harihar Milaganur Mohan Boning Yang Nicole A. Dean Malini Raghavan 《The Journal of biological chemistry》2020,295(49):16754
α1-antitrypsin (AAT) regulates the activity of multiple proteases in the lungs and liver. A mutant of AAT (E342K) called ATZ forms polymers that are present at only low levels in the serum and induce intracellular protein inclusions, causing lung emphysema and liver cirrhosis. An understanding of factors that can reduce the intracellular accumulation of ATZ is of great interest. We now show that calreticulin (CRT), an endoplasmic reticulum (ER) glycoprotein chaperone, promotes the secretory trafficking of ATZ, enhancing the media:cell ratio. This effect is more pronounced for ATZ than with AAT and is only partially dependent on the glycan-binding site of CRT, which is generally relevant to substrate recruitment and folding by CRT. The CRT-related chaperone calnexin does not enhance ATZ secretory trafficking, despite the higher cellular abundance of calnexin-ATZ complexes. CRT deficiency alters the distributions of ATZ-ER chaperone complexes, increasing ATZ-BiP binding and inclusion body formation and reducing ATZ interactions with components required for ER-Golgi trafficking, coincident with reduced levels of the protein transport protein Sec31A in CRT-deficient cells. These findings indicate a novel role for CRT in promoting the secretory trafficking of a protein that forms polymers and large intracellular inclusions. Inefficient secretory trafficking of ATZ in the absence of CRT is coincident with enhanced accumulation of ER-derived ATZ inclusion bodies. Further understanding of the factors that control the secretory trafficking of ATZ and their regulation by CRT could lead to new therapies for lung and liver diseases linked to AAT deficiency. 相似文献
59.
Anbarasi Kothandapani Akshada Sawant Venkata Srinivas Mohan Nimai Dangeti Robert W. Sobol Steve M. Patrick 《Nucleic acids research》2013,41(15):7332-7343
Base excision repair (BER) and mismatch repair (MMR) pathways play an important role in modulating cis-Diamminedichloroplatinum (II) (cisplatin) cytotoxicity. In this article, we identified a novel mechanistic role of both BER and MMR pathways in mediating cellular responses to cisplatin treatment. Cells defective in BER or MMR display a cisplatin-resistant phenotype. Targeting both BER and MMR pathways resulted in no additional resistance to cisplatin, suggesting that BER and MMR play epistatic roles in mediating cisplatin cytotoxicity. Using a DNA Polymerase β (Polβ) variant deficient in polymerase activity (D256A), we demonstrate that MMR acts downstream of BER and is dependent on the polymerase activity of Polβ in mediating cisplatin cytotoxicity. MSH2 preferentially binds a cisplatin interstrand cross-link (ICL) DNA substrate containing a mismatch compared with a cisplatin ICL substrate without a mismatch, suggesting a novel mutagenic role of Polβ in activating MMR in response to cisplatin. Collectively, these results provide the first mechanistic model for BER and MMR functioning within the same pathway to mediate cisplatin sensitivity via non-productive ICL processing. In this model, MMR participation in non-productive cisplatin ICL processing is downstream of BER processing and dependent on Polβ misincorporation at cisplatin ICL sites, which results in persistent cisplatin ICLs and sensitivity to cisplatin. 相似文献
60.
G. Smilin Bell Aseervatham Thilagar Sivasudha Mohan Suganya Angappan Rameshkumar Ramachandran Jeyadevi 《Neurochemical research》2013,38(8):1715-1725
Epilepsy prevails to be a neurological disorder in anticipation of safer drugs with enhanced anticonvulsant efficacy as presently available drugs fails to offer adequate control of epileptic seizures in about one-third of patients. The objective of this study was to evaluate the effect of Trichosanthes tricuspidata methanolic extract (TTME) against epilepsy mediated oxidative stress in pilocarpine induced mice. Intraperitonial administration of pilocarpine (85 mg/kg) induced seizure in mice was assessed by behavior observations, which is significantly (p < 0.05) reduced by TTME (100 and 200 mg/kg; i.p) in a dose dependant manner, similar to diazepam. Seizure was accompanied by significant increase in lipid peroxidation and the hippocampal nitrite content in pilocarpine group when compared with control. Moreover, the antioxidant enzymes superoxide dismutase, catalase and glutathione levels were decreased in pilocarpine administered groups. TTME administration attenuated oxidative damage as evident by decreased lipid oxidative damage and nitrite–nitrate content and restored the level of enzymatic antioxidant defenses in hippocampus. Involvement of free radicals during epilepsy is further confirmed by histopathological analysis which showed the loss of neuronal cells in hippocampus CA1 and CA3 pyramidal region. Our findings strongly support the hypothesis that TTME has anticonvulsant activity accompanied with the strong antioxidant potential plays a crucial role in reducing the oxidative stress produced by seizure. 相似文献