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41.
42.
AIM:
This study was aimed to evaluate the 5, 10-methylenetetrahydrofolate reductase (MTHFR) C677T mutation in eastern Uttar Pradesh population.MATERIALS AND METHODS:
Polymerase chain reaction (PCR) using specific primers followed by amplicon digestion by Hinf I restriction enzyme was used for MTHFR C677T polymorphism analysis. Total 250 subjects were analyzed.RESULTS:
The CC genotype was found in 192 subjects, followed by CT in 56 subjects and TT in 2 subject. Genotype frequencies of CC, CT and TT were 0.768, 0.224 and 0.008, respectively. The frequency of C allele was found to be 0.88 and that of T allele was 0.12.CONCLUSION:
It is evident from the results of the present study that the percentage of homozygous genotype (CC) is highest in the target population. 相似文献43.
Song M Basu VP Hanson MN Roques BP Bambara RA 《The Journal of biological chemistry》2008,283(6):3141-3150
Human immunodeficiency virus type 1 minus strand transfer was measured using a genomic donor-acceptor template system in vitro. Donor RNA D199, having the minimum region required for minus strong stop DNA synthesis, was previously shown to transfer with 35% efficiency to an acceptor RNA representing the 3' repeat region. Donor D520, having an additional 321-nucleotide segment extending into gag, transferred at 75% efficiency. In this study each transfer step was analyzed to account for the difference. Measurement of terminal transfer indicated that the 3' terminus of the cDNA generated using D520 is more accessible for transfer than that of D199. Nevertheless, acceptor competition experiments demonstrated that D520 has a greater preference for invasion-driven versus terminal transfer than D199. Competition mapping showed that the base of the transactivation response element is the primary invasion site for D520, important for efficient acceptor invasion. Acceptors complementary to the invasion and terminal transfer sites, but not the region between, allowed assessment of the significance of hybrid propagation by branch migration. These bipartite acceptors showed that with D520, invasion raises the local concentration of the acceptor for efficient terminal transfer by a proximity effect. However, with D199, invasion is relatively inefficient, and the cDNA 3' terminus is not very accessible. For most transfers that occurred, the acceptor accessed the cDNA 3' end by branch migration. Results suggest that both proximity and branch migration mechanisms contribute to transfers, with the proportion determined by donor-cDNA structure. D520 transfers better because it has greater accessibility for both invasion and terminus transfer. 相似文献
44.
Japanese encephalitis (JE) remains the most important cause of acute viral encephalitis and continues to spread to hitherto
unaffected regions like Indonesia, Pakistan and Australia. Approximately 60% of the world population inhabits JE endemic areas.
Despite its restricted range mostly in the developing countries, a high annual incidence of 50,000 cases and about 10,000
deaths has been reported. Disease can be fatal in 25% cases. Magnitude of the problem is even more alarming since the survivors
are left with serious long-term neuropsychiatric sequelae. Almost every two years, epidemics of JE occur in Indian subcontinent
with a high mortality. JE virus infection results in different disease manifestations in host from mild subclinical febrile
illness to clinical infections leading to encephalitis. No antiviral treatment is so far available for JE. The prevention
of JE can be achieved by controlling the vector or by immunization regime. The vector control in the rural areas, which are
the worst affected ones, is practically almost impossible. Three vaccines that have been implicated against JE include inactivated
mouse brain derived, inactivated cell culture derived and cell culture derived live attenuated JE vaccine. But each has its
own limitation. Currently, attempts to synthesize recombinant DNA vaccine are being made. New therapeutics are on the way
of development like use of minocycline, short interfering RNA, arctigenin, rosmarinic acid, DNAzymes etc. However, the immune
mechanisms that lead to JE are complex and need to be elucidated further for the development of therapeutics as well as safe
and efficacious JE vaccines. 相似文献
45.
Microwave-accelerated methylation of starch 总被引:1,自引:0,他引:1
A novel microwave-accelerated method for methylating soluble starch is described. Soluble starch could be fully methylated in 72% yield within 4.66 min using iodomethane and 30% potassium hydroxide under microwave irradiation. The completely methylated starch thus obtained was hydrolyzed with 60% HCO(2)H for 1.5 min under 80% MW power, followed by 0.05 M H(2)SO(4) for 2.0 min under 100% MW power. The partially methylated monosaccharides were separated by preparative paper chromatography and identified by their melting points and optical rotations. 相似文献
46.
Protective immunity against intracellular pathogen Mycobacterium leprae is dependent on the activation of T cells. Repeated stimulation of T cells by M. leprae antigens MLCwA (M. leprae total cell wall antigen) and ManLAM (mannose-capped lipoarabinomannan), may lead to apoptosis in leprosy patients. In the
present study, inhibition of the Fas-induced apoptosis of peripheral blood mononuclear cells of leprosy patients was investigated
using above M. leprae antigen(s), in combination with immunomodulators murabutide (MB) and a Trat peptide in particulate form (liposome). Incubation
of the cells with antigen containing the two immunomodulators in particulate form (liposomes) led to decrease in percentage
of propidium iodide positive cells and T cells expressing Fas–FasL as well as decreased caspase-8/-3 activities in lepromatous
patients, thereby inhibiting apoptosis, while converse was true upon stimulation with soluble antigen. Concurrently, there
was an upregulation of antiapoptotic protein Bcl-xL in lepromatous patients, leading to the inhibition of apoptosis. It was also observed that same formulation upregulated the
expression of CD40 on B cells and monocytes-macrophages and CD40L on T cells of lepromatous leprosy patients. The same liposomal
formulation significantly increased the expression of CD1b and CD1d on monocytes-macrophages as well as percentage of NKT
cells secreting IFN-γ in lepromatous leprosy patients. Thus, the liposomal formulation of antigen with the immunomodulators
in vitro promoted the activation of CD40:CD40L pathways and NKT cell function involved in providing cell-mediated immunity
to these patients. The same formulation also caused reversal of T cell anergy by inhibiting apoptosis through decreased expression
of death receptors (Fas–FasL) and caspase activities (3 and 8) and increased expression of antiapoptotic protein Bcl-xL in these patients. 相似文献
47.
Shuklangi A. Kulkarni Vandana Ghormade Girish Kulkarni Manisha Kapoor Santosh B. Chavan Armugam Rajendran 《Biocontrol Science and Technology》2008,18(8):809-828
Metarhizium isolates from soil (53) and insect hosts (10) were evaluated for extracellular production of cuticle degrading enzyme (CDE) activities such as chitinase, chitin deacetylase (CDA), chitosanase, protease and lipase. Regression analysis demonstrated the relation of CDE activities with Helicoverpa armigera mortality. On basis of this relation, ten isolates were selected for further evaluation. Subsequently, based on LT50 of the 10 isolates towards H. armigera, five isolates were selected. Out of these five isolates, three were selected on the basis of higher conidia production (60–75 g/kg rice), faster sedimentation time (ST50) (2.3–2.65 h in 0.1% (w/v) Tween 80) and lower LC50 (1.4–5.7×103 conidia/mL) against H. armigera. Finally, three Metarhizium isolates were selected for the molecular fingerprinting using ITS sequencing and RAPD patterning. All three isolates, M34412, M34311 and M81123, showed comparable RAPD patterns with a 935G primer. These were further evaluated for their field performance against H. armigera in a chickpea crop. The percent efficacies with the three Metarhizium isolates were from 65 to 72%, which was comparable to the chemical insecticide, endosulfan (74%). 相似文献
48.
Dwivedi AP Kumar S Varshney V Singh AB Srivastava AK Sahu DP 《Bioorganic & medicinal chemistry letters》2008,18(7):2301-2305
A series of novel N-acyl-2-arylethylamines and N-acyl-3-coumarylamines were synthesized and evaluated for their antihyperglycemic activity. Compounds 3g and 6d exhibited lowering of postprandial plasma glucose by 30.7%, 23.3% in SLM and 25.6%, 25.4% in STZ models respectively which is significant compared to metformin and glybenclamide. Other compounds exhibited moderate to good activity ranging from 19.5% to 32.8% in SLM and 3.26% to 25.4% in STZ models. 相似文献
49.
Hirani V Yarovoy A Kozeska A Magnusson RP Lasker JM 《Archives of biochemistry and biophysics》2008,478(1):59-68
P450 enzymes comprising the human CYP4F gene subfamily are catalysts of eicosanoid (e.g., 20-HETE and leukotriene B4) formation and degradation, although the role that individual CYP4F proteins play in these metabolic processes is not well defined. Thus, we developed antibodies to assess the tissue-specific expression and function of CYP4F2, one of four CYP4F P450s found in human liver and kidney. Peptide antibodies elicited in rabbits to CYP4F2 amino acid residues 61-74 (WGHQGMVNPTEEG) and 65-77 (GMVNPTEEGMRVL) recognized on immunoblots only CYP4F2 and not CYP4F3b, CYP4F11 or CYP4F12. Immunoquantitation with anti-CYP4F2 peptide IgG showed highly variable CYP4F2 expression in liver (16.4+/-18.6pmol/mg microsomal protein; n=29) and kidney cortex (3.9+/-3.8 pmol/mg; n=10), with two subjects lacking the hepatic or renal enzyme entirely. CYP4F2 content in liver microsomes was significantly correlated (r> or =0.63; p<0.05) with leukotriene B4 and arachidonate omega-hydroxylase activities, which are both CYP4F2-catalyzed. Our study provides the first example of a peptide antibody that recognizes a single CYP4F P450 expressed in human liver and kidney, namely CYP4F2. Immunoquantitation and correlation analyses performed with this antibody suggest that CYP4F2 functions as a predominant LTB4 and arachidonate omega-hydroxylase in human liver. 相似文献
50.
Biotin synthesis in Escherichia coli requires the functions of the bioH and bioC genes to synthesize the precursor pimelate moiety by use of a modified fatty acid biosynthesis pathway. However, it was previously noted that bioH has been replaced with bioG or bioK within the biotin synthetic gene clusters of other bacteria. We report that each of four BioG proteins from diverse bacteria and two cyanobacterial BioK proteins functionally replace E. coli BioH in vivo. Moreover, purified BioG proteins have esterase activity against pimeloyl-ACP methyl ester, the physiological substrate of BioH. Two of the BioG proteins block biotin synthesis when highly expressed and these toxic proteins were shown to have more promiscuous substrate specificities than the non-toxic BioG proteins. A postulated BioG-BioC fusion protein was shown to functionally replace both the BioH and BioC functions of E. coli. Although the BioH, BioG and BioK esterases catalyze a common reaction, the proteins are evolutionarily distinct. 相似文献