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71.
Sankar VH Arya V Tewari D Gupta UR Pradhan M Agarwal S 《Journal of applied genetics》2006,47(4):391-395
Microcytic hypochromic anemia is a common condition in clinical practice and alpha-thalassemia has to be considered as a differential diagnosis. Molecular diagnosis of alpha-thalassemia is possible by polymerase chain reaction. The aim of this study was to evaluate the frequency of alpha-gene numbers in subjects with microcytosis. In total, 276 subjects with microcytic hypochromic anemia [MCV<80fl; MCH<27pg] were studied. These include 125 with thalassemia trait, 48 with thalassemia major, 26 with sickle-cell thalassemia, 15 with E beta-thalassemia, 40 with iron-deficiency anemia, 8 with another hemolytic anemia, and 14 patients with no definite diagnosis. Genotyping for -alpha3.7 deletion, -alpha4.2 deletion, Hb Constant Spring, and a-triplications was done with polymerase chain reaction. The overall frequency of -alpha3.7 deletion in 276 individuals is 12.7%. The calculated allele frequency for a-thalassemia is 0.09. The subgroup analysis showed that co-inheritance of a-deletion is more frequent with the sickle-cell mutation than in other groups. We were able to diagnose 1/3 of unexplained cases of microcytosis as a-thalassemia carriers. The a-gene mutation is quite common in the Indian subcontinent. Molecular genotyping of a-thalassemia helps to diagnose unexplained microcytosis, and thus prevents unnecessary iron supplementation. 相似文献
72.
Sequence analysis and receptor specificity of the hemagglutinin of a recent influenza H2N2 virus isolated from chicken in North America 总被引:2,自引:0,他引:2
Glaser L Zamarin D Acland HM Spackman E Palese P García-Sastre A Tewari D 《Glycoconjugate journal》2006,23(1-2):93-99
Influenza viruses bind host cells following an interaction between the viral hemagglutinin (HA) protein and host cell sialylated
glycoproteins and glycolipids. Differences in binding affinities of the HAs for different types of sialic acid linkages (α2-3 vs. α2-6) contribute to determining the host range of an influenza virus. The ability of an avian influenza virus HA to bind the
human form of the receptor may be one requirement for an avian virus to propagate in the human population. In this paper,
we describe the characterization of the HA from an H2N2 virus isolated from a Pennsylvania chicken farm in 2004. Sequence
analysis revealed that this HA is a member of the Eurasian clade, and receptor binding studies show that it maintains its
specificity for the avian influenza virus α2-3 linked sialic acid receptor. 相似文献
73.
74.
Priti Dehariya Sunita Kataria K. N. Guruprasad G. P. Pandey 《Acta Physiologiae Plantarum》2012,34(3):1133-1144
The impact of ambient solar UV was studied on the photosynthesis and yield of cotton (Gossypium hirsutum) var. Vikram in a field experiment by excluding either UV-B (<315 nm) or UV-B/A (<400 nm) components of solar spectrum. Cotton
plants were grown in cages covered with polyester filters that could specifically cut off UV-B or UV-B/A part of the solar
spectrum. The control plants were grown under a filter transmissible to UV. Exclusion of UV enhanced plant height, leaf area,
total biomass, and the yield parameters (number and weight of bolls, length of fiber and number of seeds) of cotton. Enhancement
in the vegetative growth and yield of the plants could be related to enhanced rate of photosynthesis in the leaves. Polyphasic
chlorophyll a fluorescence (OJIP) transients from UV excluded plants gave a higher fluorescence yield at I–P phase. Fluorescence
measurements indicated enhanced F
v/F
m ratio and reduction capacity after exclusion of solar UV. Exclusion also enhanced stomatal conductance and intercellular
CO2 concentration and reduced the stomatal resistance. Total soluble proteins were higher after UV exclusion, and in SDS–PAGE
analysis, bands corresponding to smaller subunits (14 kDa) of Rubisco were more intensely stained. Experiments indicated suppressive
action of ambient UV on carbon fixation and yield of cotton plants. Exclusion of solar UV proved to be beneficial in enhancing
the yield of cotton plants. 相似文献
75.
Mohana Kumara P Zuehlke S Priti V Ramesha BT Shweta S Ravikanth G Vasudeva R Santhoshkumar TR Spiteller M Uma Shaanker R 《Antonie van Leeuwenhoek》2012,101(2):323-329
Rohitukine is a chromane alkaloid possessing anti-inflammatory, anti-cancer and immuno-modulatory properties. The compound
was first reported from Amoora rohituka (Meliaceae) and later from Dysoxylum binectariferum (Meliaceae) and Schumanniophyton problematicum (Rubiaceae). Flavopiridol, a semi-synthetic derivative of rohitukine is a potent CDK inhibitor and is currently in Phase
III clinical trials. In this study, the isolation of an endophytic fungus, Fusarium proliferatum (MTCC 9690) from the inner bark tissue of Dysoxylum binectariferum Hook.f (Meliaceae) is reported. The endophytic fungus produces rohitukine when cultured in shake flasks containing potato
dextrose broth. The yield of rohitukine was 186 μg/100 g dry mycelial weight, substantially lower than that produced by the
host tissue. The compound from the fungus was authenticated by comparing the LC–HRMS and LC–HRMS/MS spectra with those of
the reference standard and that produced by the host plant. Methanolic extract of the fungus was cytotoxic against HCT-116
and MCF-7 human cancer cell lines (IC50 = 10 μg/ml for both cancer cell lines). 相似文献
76.
Tewari A Lahmann C Sarkany R Bergemann J Young AR 《Photochemical & photobiological sciences》2012,11(1):216-223
Matrix metalloproteinase 1 (MMP-1) is widely regarded as a biomarker of photoageing. We tested the hypothesis that MMP-1 mRNA expression and erythema share a common action spectrum by comparing the effects of erythemally equivalent doses of UVB, UVA1 and solar simulated radiation (SSR) on acute MMP-1 mRNA expression in whole human skin in vivo. Our results show comparable MMP-1 expression with all three spectra, which supports our hypothesis. The sharing of an action spectrum implies common chromophores, one of which is likely to be DNA. We have previously shown that all spectra that we used readily induce cyclobutane thymine dimers (T<>T) in human epidermis in vivo but we lack quantitative data on damage to dermal DNA. This is important because we do not know if dermal MMP-1 induction occurs via direct damage to the dermis, or indirectly via damage to the epidermis. Our results show that UVB induces about 3 times more T<>T compared with erythemally equivalent doses of UVA1, which is similar to our published epidermal data. This supports previously published work that also implicates an unknown UVA1 chromophore for erythema and MMP-1 induction. However, the distribution of the dermal DNA damage varies considerably with spectrum. In the case of UVB it is primarily in the upper dermis, but with UVA1 it is evenly distributed. Thus, irrespective of chromophores, MMP-1 induction by direct dermal damage by both spectra is possible. The practical conclusions of our data are that the small (<5%) UVB content of solar UVR is likely to be the main cause of photoageing, at least in terms of MMP-1 expression. Furthermore, prevention of erythema by sunscreen use is likely to result in reduced MMP-1 expression. 相似文献
77.
78.
In the present investigation, a microorganism hydrolyzing carboxymethylcellulose (CMC) was isolated and identified as Bacillus subtilis strain LFS3 by 16S rDNA sequence analysis. The carboxymethylcellulase (CMCase) enzyme produced by the B. subtilis strain LFS3 was purified by (NH?)?SO? precipitation, ion exchange and gel filtration chromatography, with an overall recovery of 15 %. Native-PAGE analysis of purified CMCase revealed the molecular weight of enzyme to be about 185 kDa. The activity profile of CMCase enzyme showed the optimum activity at temperature 60 °C and pH 4.0, respectively. The enzyme activity was induced by Na?, Mg2?, NH??, and EDTA, whereas strongly inhibited by Hg2? and Fe3?. The purified enzyme hydrolyzed CMC, filter paper, and xylan, but not p-nitrophenyl β-D-glucopyranoside and cellulose. Kinetic analysis of purified enzyme showed the K(m) value of 2.2 mg/ml. Thus, acidophilic as well as thermophilic nature makes this cellulase a suitable candidate for current mainstream biomass conversion into fuel and other industrial processes. 相似文献
79.
80.
Nunez-Cruz S Yeo WC Rothman J Ojha P Bassiri H Juntilla M Davidson D Veillette A Koretzky GA Nichols KE 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(4):2311-2320
The adaptor molecule SAP (signaling lymphocytic activation molecule-associated protein) plays a critical role during NK T (NKT) cell development in humans and mice. In CD4(+) T cells, SAP interacts with the tyrosine kinase Fyn to deliver signals required for TCR-induced Th2-type cytokine production. To determine whether the SAP-dependent signals controlling NKT cell ontogeny rely on its binding to Fyn, we used the OP9-DL1 system to initiate structure function studies of SAP in murine NKT cell development. In cultures containing wild-type (WT) hematopoietic progenitors, we noted the transient emergence of cells that reacted with the NKT cell-specific agonist alpha-galactosyl ceramide and its analog PBS57. Sap(-/-) cells failed to give rise to NKT cells in vitro; however, their development could be rescued by re-expression of WT SAP. Emergence of NKT cells was also restored by a mutant version of SAP (SAP R78A) that cannot bind to Fyn, but with less efficiency than WT SAP. This finding was accentuated in vivo in Sap(R78A) knock-in mice as well as Sap(R78A) competitive bone marrow chimeras, which retained NKT cells but at significantly reduced numbers compared with controls. Unlike Sap(R78A) CD4(+) T cells, which produce reduced levels of IL-4 following TCR ligation, alpha-galactosyl ceramide-stimulated NKT cells from the livers and spleens of Sap(R78A) mice produced Th2 cytokines and activated NK cells in a manner mimicking WT cells. Thus, SAP appears to use differential signaling mechanisms in NKT cells, with optimal ontogeny requiring Fyn binding, while functional responses occur independently of this interaction. 相似文献