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91.
P Bhatt S. K. Shukla M Mahendran K Dhama M. M. Chawak J. M. Kataria 《Transboundary and Emerging Diseases》2011,58(5):458-460
Globally, the chicken infectious anaemia virus (CIAV) has gained much importance as an immunosuppressive and economically important emerging pathogen of poultry. In recent years, the virus has been detected and isolated from poultry flocks of India. The present study reports the first sero‐epidemiological investigation of the presence of CIAV infection in poultry flocks of the country. A total of 404 serum samples were collected from chicken flocks of eleven poultry farms, which contain a total of 0.34 million birds from four Northern states, suspected of having chicken infectious anaemia (CIA). Screening of the sera samples using a commercially available enzyme‐linked immunosorbent assay (ELISA) kit revealed 351 serum samples (86.88%) to be positive for CIAV antibodies. A high CIAV prevalence rate recorded in the present investigation, along with earlier virus detection reports, indicates the widespread distribution of the virus and that CIAV should be considered an economically important poultry pathogen affecting poultry industry of India. Extensive nationwide epidemiological studies are suggested for revealing the economic impact of CIA and to initiate further research along with devising and adapting suitable prevention and control strategies especially the use of suitable vaccines for safeguarding poultry health and production in the country. 相似文献
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94.
Farnaz Shapouri Tara Mahendran Mirudhubashini Govindarajan Philip Xie Olena Kocur Gianpiero D. Palermo Hassan W. Bakos Aisling Ahlstrm Gunilla Caisander Bo Xu Shun Bai Sarah Lambourne R. John Aitken 《Journal of assisted reproduction and genetics》2023,40(1):83
PurposeDeveloping optimized techniques for the isolation of human spermatozoa possessing low levels of DNA damage is an important objective for the ART industry. The purpose of this study was to compare a novel electrophoretic system (Felix™) of sperm isolation with a conventional method involving density gradient centrifugation (DGC).MethodsFive international ART Centres in Australia, India, Sweden, the USA, and China have collaborated in order to compare the quality of the sperm populations isolated by Felix™ and DGC in terms of processing time, sperm concentration, motility, vitality, and DNA integrity as assessed by 3 methods: SCSA, Halo, and TUNEL.ResultsAcross all centers, 112 comparisons were performed. Although significant differences were noted between centers in terms of the quality of the semen samples subjected for analysis, overall, both methods were equally capable of isolating populations of spermatozoa exhibiting high levels of vitality and progressive motility. The absolute numbers of spermatozoa recovered were significantly (p < 0.001) lower with the Felix™ device although sperm quality was higher with 4/5 centers reporting a significant improvement in DNA integrity relative to DGC (p < 0.01–p < 0.001). In practical terms, the Felix™ device featured a standardized 6 min preparation time whereas clinical DGC protocols varied from center to center but generally took around 40 min to complete.ConclusionsThe Felix™ device is a positive technical development capable of isolating suspensions of highly motile spermatozoa exhibiting low levels of DNA damage in a fraction of the time taken by conventional procedures such as DGC. 相似文献
95.
Expression of the common acute lymphoblastic leukaemia antigen (CALLA) in the human breast 总被引:3,自引:0,他引:3
R Mahendran R McIlhinney M O'Hare P Monaghan B Gusterson 《Molecular and cellular probes》1989,3(1):39-44
A biochemical and immunohistological study has been carried out to characterize the antigen in human breast reacting with antibodies to the common acute lymphoblastic leukaemia antigen (CALLA). Four different monoclonal antibodies to the CALLA antigen all stain the membrane of adult human myoepithelial cells. Surface labelling studies of freshly prepared human breast cells demonstrate that the anti-CALLA antibody, J5, immunoprecipitates a 100 kDa protein that co-electrophoreses with the CALLA antigen identified in the leukaemia cell line NALM-6. These results indicate that the CALLA antigen is expressed on myoepithelial cells and that the staining is not due to reactivity with a shared epitope on an unrelated molecule. 相似文献
96.
Succinylcholine-induced hyperkalemia has been reported to occur in many neurological disorders including subarachnoid hemorrhage. The purpose of this study was to compare the effect of succinylcholine on serum potassium levels in patients with ruptured cerebral aneurysms undergoing either early (less than or equal to 4 days; n = 14) or delayed (5-16 days; n = 20) surgery. Thirty-four patients were classified according to the number of days from subarachnoid hemorrhage to surgery. Arterial serum potassium levels were measured after induction of anesthesia but before succinylcholine, and 1, 5, and 10 min after the administration of succinylcholine. The electrocardiogram was continuously monitored. The mean ( +/- SD) increase in serum potassium level of 0.4 +/- 0.2 mmol/L occurred at 10 min but was not statistically significant, nor was there any statistically significant difference in serum potassium levels related to time between subarachnoid hemorrhage and administration of succinylcholine. We found no evidence of succinylcholine-induced hyperkalemia in patients undergoing either early or delayed cerebral aneurysm surgery. 相似文献
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98.
The signalling pathway for BCG-induced interleukin-6 production in human bladder cancer cells 总被引:1,自引:0,他引:1
Intravesical bacillus Calmette-Guerin (BCG) is currently the therapy of choice for superficial bladder cancer with a 60-70% response rate. Induction of cytokine production (e.g. IL-6, etc.) by BCG has been found in patient's urine in vivo as well as bladder cancer cell lines. However, the signalling mechanisms are still unclear. In this study, we investigated the effect of BCG on cAMP production and its role in regulating interleukin-6 expression in the human bladder cancer cell line, MGH. After 1 hr exposure to BCG, IL-6 gene expression in MGH cells increased by 2.5-3-fold and cAMP production increased by 8-10-fold in a time- and dose-dependent manner. BCG-induced cAMP production was inhibited by both antifibronectin antibody and an adenylate cyclase inhibitor, SQ22536 in a dose-dependent way. In the presence of SQ22536, IL-6 expression in MGH cells was also greatly reduced. Furthermore, cAMP-dependent kinase inhibitors H7 and HA1004 also inhibited BCG-induced IL-6 expression in MGH, with HA1004 being much less effective than H7. Thus, BCG induces cAMP production and may regulate interleukin-6 expression partially via a cAMP-dependent pathway in human bladder cancer cells. 相似文献
99.
Many cancers express an array of chemokines which have the capacity to modulate the nature and function of intratumoural leukocyte infiltrates. In malignant mesothelioma (MM) neither the chemokine signalling networks nor their regulation have been investigated despite the prominence of leucocytic infiltrates in both clinical and experimental tumours. In this study, we examined constitutive and cytokine-regulated expression of CC and CXC chemokine genes in mesothelioma and mesothelial cell cultures derived from two different mouse strains (BALB/C and CBA/CaH). In mouse MM and mesothelial cells MCP-1/JE, GRO-α/KC and RANTES were expressed whereas MIP-1α and MIP-2 were infrequently expressed. Comparison of basal chemokine expression showed that GRO-α/KC mRNA was overexpressed in the malignant cells whereas MCP-1 gene expression and release was downregulated. Treatment of mesothelioma cells with IL-4, IFN-γ or TNF-α revealed that chemokine genes could be more responsive to cytokines in the malignant compared to their mesothelial cells. TNF-α was consistently the most potent positive regulator of both CC and CXC chemokine expression and MCP-1 release. The present study for the first time provides a mechanistic insight into the differential regulation of chemokine expression in malignant mesothelioma cells and has implications for mesothelial chemokine signalling in mouse models. 相似文献
100.
Instillation of Bacillus Calmette Guerin (BCG) into the bladder is the standard treatment for superficial bladder cancer. It leads to a local inflammatory response due to the release of cytokines and influx of immune cells to the tumor site. Although the presence of an intact immune system is an essential criterion for successful therapy, attachment of the bacteria to the bladder urothelial is just as important. The purpose of our study is to determine the role of bacterial internalization by epithelial cells. Transfection of the alpha5 integrin gene into the BCG unresponsive bladder cancer cell line, RT4, caused an increase in bacterial uptake and also increased cell death. Treatment of cells with cycloheximide did not prevent bacterial internalization but blocked its cytotoxic effect suggesting that unlike cell death, the process of bacterial internalization does not require new protein synthesis. Our data also show that the bacteria secretory products can prevent its own internalization. The extract prepared from lyophilized BCG altered the phosphorylation status of the focal adhesion kinase which is responsible for cellular endocytosis. Therefore, bacterial phosphatases may be present in the bacterial extract. Their activity may inhibit BCG internalization. Thus washing the reconstituted bacteria to remove the enzymes before instillation into the bladder might improve the therapeutic outcome of intravesical BCG therapy. 相似文献