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Ghafourian S Mohebi R Sekawi Z Raftari M Neela V Ghafourian E Aboualigalehdari E Rahbar M Sadeghifard N 《Journal of biological regulators and homeostatic agents》2012,26(2):231-236
Carbapenems are the most potent beta-lactam agents with a broad-spectrum activity against Gram-negative and Gram-positive bacteria. They are stable in the presence of penicillinases and cephalosporinases. This study was focused on frequency of metallo beta- lactamase (MBL) among Pesudomonas aeruginosa strains isolated in patients with urinary tract infection, effect of tannin against PA positive strains which produced blaVIM or blaIMP and both of these genes (Species). Detection of MBL was performed by phonotypic and genotypic methods. Tannin extract was tested against P. aeruginosa producing MBL. During the study period, 240 P. aeruginosa isolates were identified. Among them 64 (26.6 percent) isolates were imipenem non-susceptible and confirmed by imipenem/EDTA. Our results revealed that the growth of blaVIM positive P. aeruginosa inhibited at 15 microg/ml concentration. The experiment repeated for blaIMP-positive P. aeruginosa and P. aeruginosa which harbored blaIMP and blaVIM, the results showed 35 microg/ml was the best concentration for inhibition of P. aeruginosa-positive blaIMP and also P. aeruginosa blaIMP and blaVIM. In conclusion, tannin was effective against P. aeruginosa producing blaVIM and blaIMP and both of them so it can be substituted with common antibiotics. The result showed significantly P. aeruginosa-harbored blaIMP was more responsible for imipenem resistance than P. aeruginosa-positive blaVIM. Interestingly, tannin was more effective against MBL-P. aeruginosa in comparison with current antibiotics. 相似文献
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Although CD8+ cytotoxic T lymphocyte (CTL) epitope-based DNA vaccination is valuable experience on vaccine research but many attempts are still continued to achieve acceptable protective response. To study the role of full length antigen in CTL epitope immunization, we evaluated cellular immunity of diverse patterns of complete Herpes simplex virus type 1 (HSV-1) glycoprotein B (gB) and the immunodominant CTL epitope (498–505) DNA injection in C57BL/6 mice. Optimal immune response was observed in the group immunized with the full length of gB in the first injection and CTL epitope in the second and third vaccination as assessed by lymphocyte proliferation assay (MTT), cytokine assay (ELISA) and CTL assay. B cell and spatially CD4+ T cell epitopes in full length protein might be important for appropriate priming of CTL immune response. These findings may have important implication for the improvement of CTL epitope based DNA vaccine against HSV and other pathogens. 相似文献
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Soleimanjahi H Roostaee MH Rasaee MJ Mahboudi F Kazemnejad A Bamdad T Zandi K 《FEMS immunology and medical microbiology》2006,46(1):100-106
Herpes simplex virus produces primary and latent infections with periodic recurrency. The prime-boost immunization strategies were studied using a DNA vaccine carrying the full-length glycoprotein D-1 gene and a baculovirus-derived recombinant glycoprotein D, both expressing herpes simplex virus glycoprotein D-1 protein. Immunization with recombinant DNAs encoding antigenic proteins could induce cellular and humoral responses by providing antigen expression in vivo. Higher immune response, however, occurred when the recombinant proteins followed DNA inoculation. While all groups of the immunized mice and positive control group could resist virus challenge, a higher virus neutralizing antibody level was detected in the animals receiving recombinant protein following DNA vaccination. 相似文献
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Malekzadeh F. Farazmand A. Ghafourian H. Shahamat M. Levin M. Colwell R.R. 《World journal of microbiology & biotechnology》2002,18(4):295-302
Pseudomonas MGF-48, a gram-negative, motile, oxidase-negative, catalase-positive, yellow-pigmented bacterium isolated from electroplating
effluent, was found to accumulate uranium with high efficiency. Uptake of uranium was rapid and the amount increased in direct
proportion to concentration, e.g., from 50 to 200 mg uranium per liter. The largest amount of uranium uptake was 174 mg per
gram dry weight bacterial biomass and was observed to occur in stationary phase during incubation at 30 °C. Uptake was determined
by flow injection analysis. Maximum uranium accumulation occurred at pH 6.5, with 86% of the uranium being taken up within
5 min of incubation. Release of uranium bound to the cells was accomplished by addition of sodium carbonate and EDTA solution
(0.1 M), the cells were reusable, and served as a biosorbent. Cells immobilized in polyacrylamide gel took up 90% of the uranium.
Pseudomonas MGF-48 showed excellent efficiency in biosorbing uranium, by both immobilized and free cells. The results of this study,
compared with those of other reports of uranium accumulation by microorganisms, leads us to conclude that Pseudomonas MGF-48 shows excellent potential for bioremediating uranium-polluted aqueous effluents.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Asadollahi Parisa Pakzad Iraj Sadeghifard Nourkhoda Ghafourian Sobhan Kazemian Hossein Kaviar Vahab Hassan Fattahi Roohollah Kalani Behrooz Sadeghi 《International journal of peptide research and therapeutics》2022,28(1):1-12
International Journal of Peptide Research and Therapeutics - Amino acids are the principal constituent of peptides and proteins. The ever-going expansion beyond non-canonical amino acids is one of... 相似文献
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Fereydoon Malekzadeh Saeid Ghorbanzadeh Mashkani Hossein Ghafourian Mohammad Reza Soudi 《World journal of microbiology & biotechnology》2007,23(7):905-910
An attempt was made to isolate bacterial strains capable of biologically removing tungstate (WO42−). Thirty-eight water samples were collected from various areas of Anzali lagoon, Iran. Initial screening of a total of 100
bacterial isolates at pH 5, resulted in the selection of one isolate with maximum adsorption capacity of 65.4 mg tungstate/g
dry weight. It was tentatively identified as Bacillus sp. according to morphological and biochemical properties and named strain MGG-83. Tungsten concentration was measured spectrophotometrically
using the dithiol method. Higher adsorption capacity was observed in the acidic pH ranging from 1 to 3. At pH 2, the strain
removed 274.4 mg tungstate/g dry weight within 5 min from the solution with 300 mg WO42−/l initial concentration and thereafter adsorption rate decreased remarkably. The applicability of the Freundlich isotherm
for representation of the experimental data was investigated. Using 1 mM sodium azide and 10 mM 2,4−dinitrophenol, it was
shown that only 20% reduction occurred in adsorption and steam sterilization of the bacterial cells resulted in 11% decrease
in tungstate uptake. Temperature variations (20–40°C) had no significant effect on tungstate uptake. Pretreatment with the
cations had no effect in uptake but pretreatment with anions decreased the tungstate uptake as indicated: sulfate > chromate > nitrate > molybdate > selenate > rhenate.
Tungstate was removed from metal-laden biomass after desorption treatments by addition of different desorbing solutions with
the results sodium acetate > EDTA > NaCl > KOH > H2SO4. 相似文献