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51.
Sunil Kumar GB Ganapathi TR Revathi CJ Prasad KS Bapat VA 《Protein expression and purification》2003,32(1):10-17
Hepatitis B virus ' s ' gene coding for surface antigen was cloned into plant transformation vectors pHER100 and pHBs100 with and without endoplasmic reticulum retention signal, respectively. Transformed tobacco cell lines were analyzed for the integration of the transgene by PCR and Southern blot hybridization. Expression levels as determined by ELISA showed maximum expression levels of 2 microg HBsAg gm(-1) fresh weight and 10 ng mL(-1) of spent medium in pHER100 transformed cells. Western blot analysis confirmed the presence of 24 kDa band specific to HBsAg in the transformed cells. HBsAg was expressed both as intracellular and secreted forms in pHER100 transformed cells. The buoyant density in CsCl of HBsAg derived from pHBs100 transformed tobacco cells was determined and found to be 1.095 g mL(-1). HBsAg obtained from transformed tobacco cells is similar to the human serum derived one in buoyant density properties. This is the first report on the secretion of HBsAg particles by plant cells into the cell culture medium. 相似文献
52.
This paper reports the infection of freshwater prawns belonging to the genus Macrobrachium by the isopod parasite Tachaea spongillicola in a freshwater river system of southeastern India. 相似文献
53.
The RET receptor: function in development and dysfunction in congenital malformation 总被引:17,自引:0,他引:17
Germline mutations in the RET proto-oncogene are responsible for two unrelated neural crest disorders: Hirschsprung disease, a congenital absence of the enteric nervous system in the hindgut, and multiple endocrine neoplasia type 2, a dominantly inherited cancer syndrome. Moreover, somatic rearrangements of RET are causally involved in the genesis of papillary thyroid carcinoma. The receptor tyrosine kinase encoded by the RET gene acts as the subunit of a multimolecular complex that binds four distinct ligands and activates a signalling network crucial for neural and kidney development. Over the past few years, a clearer picture of the mode of RET activation and of its multifaceted role during development has started to emerge. These findings, which provide new clues to the molecular mechanisms underlying RET signalling dysfunction in Hirschsprung disease, are summarized in this review. 相似文献
54.
The structure, growth, differentiation and function of crustacean chelipeds are reviewed. In many decapod crustaceans growth
of chelae is isometric with allometry level reaching unity till the puberty moult. Afterwards the same trend continues in
females, while in males there is a marked spurt in the level of allometry accompanied by a sudden increase in the relative
size of chelae. Subsequently they are differentiated morphologically into crusher and cutter making them heterochelous and
sexually dimorphic. Of the two, the major chela is used during agonistic encounters while the minor is used for prey capture
and grooming. Various biotic and abiotic factors exert a negative effect on cheliped growth. The dimorphic growth pattern
of chelae can be adversely affected by factors such as parasitic infection and substrate conditions. Display patterns of chelipeds
have an important role in agonistic and aggressive interactions. Of the five pairs of pereiopods, the chelae are versatile
organs of offence and defence which also make them the most vulnerable for autotomy. Regeneration of the autotomized chelipeds
imposes an additional energy demand called “regeneration load” on the incumbent, altering energy allocation for somatic and/or reproductive processes. Partial withdrawal of chelae leading
to incomplete exuviation is reported for the first time in the laboratory and field inMacrobrachiumspecies. 相似文献
55.
Mezghrani A Courageot J Mani JC Pugniere M Bastiani P Miquelis R 《The Journal of biological chemistry》2000,275(3):1920-1929
Thyroglobulin (TG) is secreted by the thyrocytes into the follicular lumen of the thyroid. After maturation and hormone formation, TG is endocytosed and delivered to lysosomes. Quality control mechanisms may occur during this bidirectional traffic since 1) several molecular chaperones are cosecreted with TG in vivo, and 2) lysosomal targeting of immature TG is thought to be prevented via the interaction, in acidic conditions, between the Ser(789)-Met(1172) TG hormonogenic domain (BD) and an unidentified membrane receptor. We investigated the secretion and cell surface expression of PDI and other chaperones in the FRTL5 thyroid cell line, and then studied the characteristics of the interaction between TG and PDI. We demonstrated that PDI, but also other chaperones such as calnexin and KDEL-containing proteins are exposed at the cell surface. We observed on living cells or membrane preparations that PDI specifically binds TG in acidic conditions, and that only BD is involved in binding. Surface plasmon resonance analysis of TG/PDI interactions indicated: 1) that PDI bound TG but only in acidic conditions, and that it preferentially recognized immature molecules, and 2) BD is involved in binding even if cysteine-rich modules are deleted. The notion that PDI acts as an "escort" for immature TG in acidic post-endoplasmic reticulum compartments is discussed. 相似文献
56.
57.
Rohit Saxena Praveen Vashist Radhika Tandon R. M. Pandey Amit Bhardawaj Vimala Menon Kalaivani Mani 《PloS one》2015,10(2)
PurposeAssess prevalence of myopia and identify associated risk factors in urban school children.MethodsThis was a cross-sectional study screening children for sub-normal vision and refractive errors in Delhi. Vision was tested by trained health workers using ETDRS charts. Risk factor questionnaire was filled for children with vision <6/9.5, wearing spectacles and for a subset (10%) of randomly selected children with normal vision. All children with vision <6/9.5 underwent cycloplegic refraction. The prevalence of myopia <-0.5 diopters was assessed. Association of risk factors and prevalence of myopia was analyzed for children with myopia and randomly selected non myopic children and adjusted odds ratio values for all risk factors were estimated.ResultsA total number of 9884 children were screened with mean age of 11.6 + 2.2 years and 66.8% boys. Prevalence of myopia was 13.1% with only 320 children (24.7%) wearing appropriate spectacles. Mean myopic spherical error was -1.86 + 1.4 diopters. Prevalence of myopia was higher in private schools compared to government schools (p<0.001), in girls vs. boys (p = 0.004) and among older (> 11 years) children (p<0.001). There was a positive association of myopia with studying in private schools vs. government schools (p<0.001), positive family history (p< 0.001) and higher socio-economic status (p = 0.037). Positive association of presence of myopia was observed with children studying/reading > 5 hours per day (p < 0.001), watching television > 2 hours / day (p < 0.001) and with playing computer/video/mobile games (p < 0.001). An inverse association with outdoor activities/playing was observed with children playing > 2 hours in a day.ConclusionMyopia is a major health problem in Indian school children. It is important to identify modifiable risk factors associated with its development and try to develop cost effective intervention strategies. 相似文献
58.
59.
Intensified antineoplastic effect by combining an HDAC‐inhibitor,an mTOR‐inhibitor and low dosed interferon alpha in prostate cancer cells 下载免费PDF全文
Igor Tsaur Lukasz Hudak Jasmina Makarević Eva Juengel Jens Mani Hendrik Borgmann Kilian M. Gust David Schilling Georg Bartsch Karen Nelson Roman A. Blaheta 《Journal of cellular and molecular medicine》2015,19(8):1795-1804
A significant proportion of men diagnosed with prostate cancer (PCa) eventually develop metastatic disease, which progresses to castration resistance, despite initial response to androgen deprivation. As anticancer therapy has become increasingly effective, acquired drug resistance has emerged, limiting efficacy. Combination treatment, utilizing different drug classes, exemplifies a possible strategy to foil resistance development. The effects of the triple application of the histone deacetylase (HDAC) inhibitor valproic acid (VPA), the mammalian target of rapamycin inhibitor everolimus and low dosed interferon alpha (IFNα) on PCa cell growth and dissemination capacity were investigated. For that purpose, the human PCa cell lines, PC‐3, DU‐145 and LNCaP were treated with the combined regimen or separate single agents. Cell growth was investigated by the MTT dye reduction assay. Flow cytometry served to analyse cell cycle progression. Adhesion to vascular endothelium or immobilized collagen, fibronectin and laminin was quantified. Migration and invasion characteristics were determined by the modified Boyden chamber assay. Integrin α and β subtypes were investigated by flow cytometry, western blotting and RT‐PCR. Integrin related signalling, Epidermal Growth Factor Receptor (EGFr), Akt, p70S6kinase and extracellular signal‐regulated kinases (ERK)1/2 activation were also assessed. The triple application of VPA, everolimus and low dosed IFNα blocked tumour cell growth and dissemination significantly better than any agent alone. Antitumour effects were associated with pronounced alteration in the cell cycle machinery, intracellular signalling and integrin expression profile. Combining VPA, everolimus and low dosed IFNα might be a promising option to counteract resistance development and improve outcome in PCa patients. 相似文献
60.
Julie Baby Reeta Subramaniam Mani Swapna Susan Abraham Asha T. Thankappan Prasad Madhavan Pillai Ashwini Manoor Anand Shampur Narayan Madhusudana Jayachandran Ramachandran Sachin Sreekumar 《PLoS neglected tropical diseases》2015,9(7)