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排序方式: 共有490条查询结果,搜索用时 15 毫秒
1.
M S Jawahar S Sivasubramanian V K Vijayan C V Ramakrishnan C N Paramasivan V Selvakumar S Paul S P Tripathy R Prabhakar 《BMJ (Clinical research ed.)》1990,301(6748):359-362
OBJECTIVE--To assess the efficacy of a short course chemotherapy regimen for treating tuberculosis of the lymph nodes in children. DESIGN--Open, collaborative, outpatient clinical trial. SETTING--Outpatient department of the Tuberculosis Research Centre, paediatric surgery departments of the Institute of Child Health and Hospital for Children and the Government Stanley Hospital, Madras, South India. PATIENTS--Children aged 1-12 years with extensive, multiple site, superficial tuberculous lymphadenitis confirmed by biopsy (histopathology or culture). INTERVENTIONS--Patients were treated with a fully supervised intermittent chemotherapy regimen consisting of streptomycin, rifampicin, isoniazid, and pyrazinamide three times a week for two months followed by streptomycin and isoniazid twice a week for four months on an outpatient basis. Surgery was limited to biopsy of nodes for diagnosis and assessment. MAIN OUTCOME MEASURES--Response to chemotherapy was assessed by regression of lymph nodes and healing of sinuses and abscesses during treatment and follow up. Compliance with treatment and frequency of adverse reactions were also estimated. RESULTS--197 Patients were admitted to the study and 168 into the analysis. The regimen was well tolerated and compliance was good with 101 (60%) patients receiving the prescribed chemotherapy within 15 days of the stipulated period of six months. Those whose chemotherapy extended beyond that period received the same total number of doses. Clinical response was favourable in most patients at the end of treatment. Sinuses and abscesses healed rapidly. Residual lymphadenopathy (exceeding 10 mm diameter) was present in 50 (30%) patients at the end of treatment; these nodes were biopsied. Fresh nodes, increase in size of nodes, and sinuses and abscesses occurred both during treatment and follow up. After 36 months of follow up after treatment only 5 (3%) patients required retreatment for tuberculosis. CONCLUSION--Tuberculous lymphadenitis in children can be successfully treated with a short course chemotherapy regimen of six months. 相似文献
2.
The metabolism of pregnenolone in subcellular fractions of the testes of the macaque (Macaca fascicularis) has been studied using capillary gas chromatography to characterize and quantify the metabolites, after their conversion into the O-methyloxime and/or trimethylsilyl ether derivatives. The microsomal incubations yielded the greatest quantities of metabolites, with lesser amounts in the mitochondrial fraction. The cytosolic fraction contained no significant quantity of metabolites after incubation, except for 5alpha-androst-16-en-3 beta-ol. This, and other odorous androst-16-enes, found in the microsomal fraction, are of particular interest in the context of animal communication because of their possible pheromonal role. Pregnenolone was converted into androst-5-ene-3 beta,17 beta-diol, androst-4-ene-3,17-dione and testosterone, suggesting that both classical pathways for testosterone synthesis were operating. Testosterone was further converted into 5 alpha-reduced androstanediols, especially in the microsomal fraction. 相似文献
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4.
A bacterial invasin induces macrophage apoptosis by binding directly to ICE. 总被引:42,自引:1,他引:41
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Shigella, the etiological agent of dysentery, kills macrophages by inducing apoptosis. Deletion mutants in the invasion invasion plasmid antigen B (ipaB) of Shigella flexneri are not cytotoxic. Here, we localized IpaB to the cytoplasm of macrophages infected with S. flexneri. Purified IpaB induced apoptosis when microinjected into macrophages, indicating that IpaB is sufficient to induce apoptosis. Using a GST-IpaB fusion protein as a ligand in affinity purification, we isolated four IpaB binding proteins from macrophages which were identified as the precursor and the mature polypeptides of interleukin-1beta converting enzyme (ICE) or a highly homologous protease. We found that IpaB binds directly to ICE and this enzyme is activated during S. flexneri infection. Furthermore, specific inhibitors of ICE prevented Shigella-induced apoptosis. 相似文献
5.
The polyamines stimulated tyrosine hydroxylase in whole homogenates of bovine caudate nuclei approximately 2 fold. TheV
max forl-tyrosine increased by 2.3 fold while theK
m
s forl-tyrosine and for the cofactor (DMPH4) were unchanged.l-Aromatic amino acid decarboxylase from whole rat brain homogenate was stimulated by about 40% in the presence of polyamines. These findings suggest that increased polyamine levels associated with increased cellular synthetic activity can modify the synthesis of neurotransmitters. 相似文献
6.
Abstract— It has been reported that myelin basic protein (MBP) forms a specific complex with S-100 protein in the presence of either Ca2+ or Mn2+, as detected by Immunoelectrophoresis. We have now studied the binding of Ca2+ and Mn2+ to these two proteins. We find that MBP binds 1 mol of Mn2+/mol of protein, and this binding produces an increment in its fluorescence, indicating a conformational change. Ca2+ does not bind to MBP nor does it affect the fluorescence of MBP. S-100 protein, as has been reported, binds about 10 mol of Ca2+/mol and this binding produces a conformational change. S-100 protein also has 25 binding sites for Mn2+, but this binding does not alter fluorescence and does not appear to affect conformation. Competitive binding experiments demonstrate that the binding sites of S-100 protein for Ca2+ and Mn2+ are independent. The alteration of electrophoretic migration in gels of S-100 protein produced by Ca2+ and of MBP produced by Mn2+ are in accord with the observations based on fluorescence. Mn2+ does not affect the electrophoretic mobility of S-100. These results indicate that the formation of the complex between MBP and S-100 protein in the presence of either Ca2+ or Mn2+ is due to the conformational change induced by these ions in S-100 protein, MBP, or both. 相似文献
7.
Kanjoormana Aryan Manu Muthu K. Shanmugam Tina H. Ong Aruljothi Subramaniam Kodappully Sivaraman Siveen Ekambaram Perumal Ramar Perumal Samy Pradeep Bist Lina H. K. Lim Alan Prem Kumar Kam M. Hui Gautam Sethi 《PloS one》2013,8(3)
Accumulating evidence(s) indicate that CXCL12-CXCR4 signaling cascade plays an important role in the process of invasion and metastasis that accounts for more than 80% of deaths in hepatocellular carcinoma (HCC) patients. Thus, identification of novel agents that can downregulate CXCR4 expression and its associated functions have a great potential in the treatment of metastatic HCC. In the present report, we investigated an anthraquinone derivative, emodin for its ability to affect CXCR4 expression as well as function in HCC cells. We observed that emodin downregulated the expression of CXCR4 in a dose-and time-dependent manner in HCC cells. Treatment with pharmacological proteasome and lysosomal inhibitors did not have substantial effect on emodin-induced decrease in CXCR4 expression. When investigated for the molecular mechanism(s), it was observed that the suppression of CXCR4 expression was due to downregulation of mRNA expression, inhibition of NF-κB activation, and abrogation of chromatin immunoprecipitation activity. Inhibition of CXCR4 expression by emodin further correlated with the suppression of CXCL12-induced migration and invasion in HCC cell lines. In addition, emodin treatment significantly suppressed metastasis to the lungs in an orthotopic HCC mice model and CXCR4 expression in tumor tissues. Overall, our results show that emodin exerts its anti-metastatic effect through the downregulation of CXCR4 expression and thus has the potential for the treatment of HCC. 相似文献
8.
Kaliappan Gopal Perumal Nagarajan Jose Jedy Avinash T. Raj S. Kalai Gnanaselvi Parveen Jahan Yogendra Sharma Esaki M. Shankar Jerald M. Kumar 《PloS one》2013,8(6)
Abdominal aortic aneurysm (AAA) is a common chronic degenerative disease characterized by progressive aortic dilation and rupture. The mechanisms underlying the role of α-tocopherol and β-carotene on AAA have not been comprehensively assessed. We investigated if α-tocopherol and β-carotene supplementation could attenuate AAA, and studied the underlying mechanisms utilized by the antioxidants to alleviate AAA. Four-months-old Apoe−/− mice were used in the induction of aneurysm by infusion of angiotensin II (Ang II), and were orally administered with α-tocopherol and β-carotene enriched diet for 60 days. Significant increase of LDL, cholesterol, triglycerides and circulating inflammatory cells was observed in the Ang II-treated animals, and gene expression studies showed that ICAM-1, VCAM-1, MCP-1, M-CSF, MMP-2, MMP-9 and MMP-12 were upregulated in the aorta of aneurysm-induced mice. Extensive plaques, aneurysm and diffusion of inflammatory cells into the tunica intima were also noticed. The size of aorta was significantly (P = 0.0002) increased (2.24±0.20 mm) in the aneurysm-induced animals as compared to control mice (1.17±0.06 mm). Interestingly, β-carotene dramatically controlled the diffusion of macrophages into the aortic tunica intima, and circulation. It also dissolved the formation of atheromatous plaque. Further, β-carotene significantly decreased the aortic diameter (1.33±0.12 mm) in the aneurysm-induced mice (β-carotene, P = 0.0002). It also downregulated ICAM-1, VCAM-1, MCP-1, M-CSF, MMP-2, MMP-9, MMP-12, PPAR-α and PPAR-γ following treatment. Hence, dietary supplementation of β-carotene may have a protective function against Ang II-induced AAA by ameliorating macrophage recruitment in Apoe−/− mice. 相似文献
9.
Jesu Arockiaraj Annie J. Gnanam Rajesh Palanisamy Venkatesh Kumaresan Prasanth Bhatt Muthukumaresan Kuppusamy Thirumalai Arpita Roy Mukesh Pasupuleti Marimuthu Kasi Akila Sathyamoorthi Abirami Arasu 《Biochimie》2013
In this study, we report the bioinformatics characterization, gene expression, transglutaminase activity and coagulation assays of transglutaminase (TGase) of freshwater prawn Macrobrachium rosenbergii identified from the constructed cDNA library by GS FLX™ technology. Even though, TGase have sequence similarity, they differ extensively in their substrate specificity and are thought to play an important in variety of functions such as development, tissue differentiation and immune responses etc. Gene expression studies show that MrTGase is widely distributed in the tissues such as heart, muscle, intestine, brain, etc., but higher amounts are found in hemocyte. Results of TGase mRNA relative expression in hemocyte, before and after infected with white spot syndrome baculovirus (WSBV) and Vibrio harveyi show that the gene expression initially increases up to 24 h and then it falls down. Coagulation assay results showed that the endogenous TGase is involved in the rapid assembly of a specific, plasma clotting protein. Structural studies show that MrTGase contains a typical TGc domain between 323 and 424, and two putative integrin-binding motifs at Arg180–Gly181–Asp182 and Arg269–Gly270–Asp271. The predicted 3D model of MrTGase contains 47.04% coils (366 amino acid residues), 26.74% extended strand (208 residues), 21.72% α-helix (169 residues) and 4.5% beta turns (35 residues). BLASTp analysis of MrTGase exhibited high sequence similarities with other crustacean TGase, with the highest observed in white shrimp (77.1%). Moreover, the phylogenetic analysis also showed that MrTGase clustered with the other members of crustacean TGase. Overall, these results suggested that MrTGase is a major and functional TGase of M. rosenbergii for haemolymph coagulation and also in spread of infection. 相似文献
10.
J. Asnet Mary R. Paramasivan B.K. Tyagi M. Surender 《Journal of biomolecular structure & dynamics》2013,31(10):1077-1085
Chikungunya fever is one of the reemerging vector-borne diseases. It has become a major global health problem especially in the developing countries. There are no vaccines or specific antiviral drugs available to date. This study reports small molecule inhibitors of envelope glycoprotein 2 (E2 glycoprotein) which are predicted based on Chikungunya virus–host interactions. E2 glycoprotein of Chikungunya virus interacts at 216 residue of the host receptor protein which plays a vital role in initiating infection. Understanding the structural aspects of E2 glycoprotein is crucial to develop specific inhibitors to prevent the virus binding from host receptors. In silico method was adopted to predict the sequence motifs of envelope protein, as the method like yeast two hybrid system is laborious, time consuming, and costly. The E2 glycoprotein structure of the Indian isolate was modeled using two templates (2XFC and 3JOC) and then validated. The class III PDZ domain binding motif was found to be identified at 213–216 amino acids. The corresponding peptide structures which recognize the PDZ domain binding motif were identified by the literature search and were used for generating five point pharmacophore model (ADDDR) containing acceptor, donor and aromatic ring features. Databases such as Asinex, TosLab and Maybridge were searched for the matches for the predicted pharmacophore model. Two compounds were identified as lead molecules as their glide score is?>?5?kcal/mol. Since the pharmacophore model is developed based on Chikungunya virus–host interaction, it can be used for designing promising antiviral lead compounds for the treatment of Chikungunya fever.An animated Interactive 3D Complement (I3DC) is available in Proteopedia at http://proteopedia.org/w/Journal:JBSD:21 相似文献