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991.
S Abbasalizadeh G Salehi Jouzani M Motamedi Juibari R Azarbaijani L Parsa Yeganeh M Ahmad Raji M Mardi GH Salekdeh 《Journal of bacteriology》2012,194(16):4431
Ureibacillus thermosphaericus strain Thermo-BF is an aerobic, thermophilic bacillus which has been characterized to biosynthesize gold nanoparticles. Here we present the draft genome sequence of Ureibacillus thermosphaericus strain Thermo-BF which consists of a 2,864,162-bp chromosome. This is the first report of a shotgun sequenced draft genome of a species in the Ureibacillus genus. 相似文献
992.
Nalini Kumar Vudattu Sharon Kuhlmann-Berenzon Mohsen Khademi Vicki Seyfert Thomas Olsson Markus J. Maeurer 《PloS one》2009,4(8)
Background
High content immune profiling in peripheral blood may reflect immune aberrations associated with inflammation in multiple sclerosis (MS) and other autoimmune diseases affecting the central nervous system.Methods and Findings
Peripheral blood mononuclear cells from 46 patients with multiple sclerosis (MS), 9 patients diagnosed with relapsing remitting MS (RRMS), 13 with secondary progressive multiple sclerosis (SPMS), 9 with other neurological diseases (OND) and well as 15 healthy donors (HD) were analyzed by 12 color flow cytometry (TCRαβ, TCRγδ, CD4, CD8α, CD8β, CD45RA, CCR7, CD27, CD28, CD107a, CD127, CD14) in a cross-sectional study to identify variables significantly different between controls (HD) and patients (OND, RRMS, SPMS). We analyzed 187 individual immune cell subsets (percentages) and the density of the IL-7 receptor alpha chain (CD127) on 59 individual immune phenotypes using a monoclonal anti-IL-7R antibody (clone R34.34) coupled to a single APC molecule in combination with an APC-bead array. A non-parametric analysis of variance (Kruskal-Wallis test) was conducted in order to test for differences among the groups in each of the variables. To correct for the multiplicity problem, the FDR correction was applied on the p-values. We identified 19 variables for immune cell subsets (percentages) which allowed to segregate healthy individuals and individuals with CNS disorders. We did not observe differences in the relative percentage of IL-7R-positive immune cells in PBMCs. In contrast, we identified significant differences in IL-7 density, measured on a single cell level, in 2/59 variables: increased numbers of CD127 molecules on TCRαβ+CD4+CD25 (intermed) T-cells and on TCRαβ+CD4+CD25−CD107a+ T-cells (mean: 28376 Il-7R binding sites on cells from HD, 48515 in patients with RRMS, 38195 in patients with SPMS and 33692 IL-7 receptor binding sites on cells from patients with OND).Conclusion
These data show that immunophenotyping represents a powerful tool to differentiate healthy individuals from individuals suffering from neurological diseases and that the number of IL-7 receptor molecules on differentiated TCRαβ+CD4+CD25−CD107a+ T-cells, but not the percentage of IL-7R-positive cells, segregates healthy individuals from patients with neurological disorders. 相似文献993.
Ismael León-Rivera Gumersindo Mirón-López Samuel Estrada-Soto Francisco Aguirre-Crespo María del Carmen Gutiérrez Gloria María Molina-Salinas Gerardo Hurtado Gabriel Navarrete-Vázquez Elizur Montiel 《Bioorganic & medicinal chemistry letters》2009,19(16):4652-4656
Tyrianthins A (1) and B (2), two new partially acylated glycolipid ester-type heterodimers were isolated from Ipomoea tyrianthina. Scammonic acid A was determined as the glycosidic acid in both monomeric units. Tyrianthin A (1) (IC50 0.24 ± 0.09 μM and Emax 81.80 ± 0.98%), and tyrianthin B (2) (IC50 0.14 ± 0.08 μM and Emax 87.68 ± 0.72%) showed significant in vitro relaxant effect on aortic rat rings, in endothelium- and concentration-dependent manners. Also, these compounds were able to increase the release of GABA and glutamic acid in brain cortex, and displayed weak antimycobacterial activity. 相似文献
994.
Marjan Sabbaghian Azadeh Ebrahim-Habibi Mohsen Nemat-Gorgani 《International journal of biological macromolecules》2009,44(2):156-162
Protein aggregation is of crucial importance in a wide variety of situations. High temperatures, combined with other denaturing conditions, have been used very extensively to decipher some of the fundamentals related to formation of amorphous and fibrillar protein aggregates. The present study reports on the dependency of thermal aggregation of bovine liver glutamate dehydrogenase (GDH), a well-characterized allosteric enzyme, on its conformational state. The initial phases of thermal aggregation of this protein was followed in the presence of a number of well-known allosteric ligands. Positive effectors were found to decrease the rate and extent of aggregation in a concentration dependent manner, while negative effectors did the reverse. ADP, one of the most characterized GDH activators was found to stabilize a specific protein conformation resulting in loss of propensity to aggregate. The importance of this observation related to control of protein–protein interactions leading to protein aggregation is discussed. 相似文献
995.
S. Farooq I. Hussain M.A. Mir M.A. Bhat S.A. Wani 《Letters in applied microbiology》2009,48(6):692-697
Aims: To study the prevalence and characterize atypical enteropathogenic Escherichia coli (EPEC) and Shiga toxin producing E. coli (STEC) in avian species in India. Methods and Results: Two hundred and twelve faecal samples collected from 62 chickens, 50 ducks and 100 pigeons were investigated for the presence of stx1, stx2, eae and ehxA virulence genes by multiplex PCR. In all, 42 E. coli isolates (25 chicken, 2 duck and 15 pigeon) possessed at least one virulence gene. Out of these, nine (4·24%) isolates were STEC and 33 (15·56%) were EPEC. All isolates from duck and chicken were EPEC while among 15 pigeon isolates nine (60%) were STEC and six (40%) were EPEC. Among the STEC isolates four each carried stx1 or stx2 and one possessed both stx1 and stx2. Subtype analysis of stx revealed the presence of stx2f in four STEC isolates. None of the STEC isolates carried stx1c, stx2c, stx2d or stx2e. Isolates carrying stx2f demonstrated vero cell toxicity. One each belonged to serogroup O17 and O78, while one was rough and the other untypeable. All EPEC isolates were atypical as they lacked bfpA. This appears to be the first report of detection of stx2f from India. Conclusions: The study established the presence of stx1 and stx2f containing E. coli in pigeons and atypical EPEC in poultry in India. Pigeons might serve as vectors for transmission of STEC to environment and humans. Significance and Impact of the Study: Taking into account the close contact between fanciers and pigeons, these findings warrant a more critical appraisal of these zoonotic pathogens in pigeons and humans. 相似文献
996.
Immune deficits account for the high frequency of life threatening bacterial, viral, and fungal opportunistic infections seen
in allogeneic HSCT recipients. Despite advances in infectious disease management, the integrity of host defenses remains the
mainstay of defense. The intensity of the preparative regimen, degree of HLA matching, source of stem cells (marrow, blood,
or cord), extent of T-cell depletion, and immunosuppressive therapy are some of the factors that impact the kinetics, characteristics,
and quality of immune reconstitution. Graft-versus-host disease and its prophylaxis or treatment produce a host environment
that is particularly vulnerable to infections. Mucosal disruption and prolonged severe neutropenia usually confine their impact
to the early course of transplant. After initial engraftment, HSCT recipients remain at great risk for opportunistic infections
and this is related to prolonged and severe T-lymphocyte dysfunction of a complex multifactorial nature. B cell dysfunction
is less problematic clinically, but includes deficiencies of immunoglobulin subclasses and impaired ability to mount a vaccine
response. Advances in understanding of these immune deficits have resulted in successful strategies including revaccination,
growth factors, thymic protection, and adoptive cellular therapy with antigen-specific cells. 相似文献
997.
Mohammad H. Sekhavati Mohsen Danesh Mesgaran Tahereh Mohammadabadi Adham Fani Maleki 《Mycological Research》2009,113(10):1146-1153
This paper describes the use of a quantitative competitive polymerase chain reaction (QC-PCR) assay; using PCR primers to the rRNA locus of rumen fungi and a standard-control DNA including design and validation. In order to test the efficiency of this method for quantifying anaerobic rumen fungi, it has been attempted to evaluate this method in in vitro conditions by comparing with an assay based on measuring cell wall chitin. The changes in fungal growth have been studied when they are grown in in vitro on either untreated (US) or sodium hydroxide treated wheat straw (TS). Results showed that rumen fungi growth was significantly higher in treated samples compared with untreated during the 12 d incubation (P < 0.05) and plotting the chitin assay's results against the competitive PCR's showed high positive correlation (R2 ≥ 0.87). The low mean values of the coefficients of variance in repeatability in the QC-PCR method against the chitin assay demonstrated more reliability of this new approach. And finally, the efficiency of this method was investigated in in vivo conditions. Samples of rumen fluid were collected from four fistulated Holstein steers which were fed four different diets (basal diet, high starch, high sucrose and starch plus sucrose) in rotation. The results of QC-PCR showed that addition of these non-structural carbohydrates to the basal diets caused a significant decrease in rumen anaerobic fungi biomass. The QC-PCR method appears to be a reliable and can be used for rumen samples. 相似文献
998.
Mohsen Mohamed Selim Asker Mohamed Fawzy Ramadan Samir Khalf Abd El-Aal Ebtsam Mokhtar Mohamed El-Kady 《World journal of microbiology & biotechnology》2009,25(5):789-794
Trehalose synthase (TSII) from Corynebacterium nitrilophilus NRC was successively purified by ammonium sulphate precipitation, ion exchange chromatography on DEAE-cellulose and gel filtration
chromatography on Sephadex G-100 columns. The specific activity of the trehalose synthase was increased ~200-fold, from 0.14
U mg−1 protein to 28.3 U mg−1 protein. TSII was found to be a monomeric protein with a molecular weight of 67–69 kDa. Characterization of the enzyme exhibited
optimum pH and temperature were 7.5 and 35°C, respectively. The purified enzyme was stable from pH 6.6 to 7.8 and able to
prolong its thermal stability up to 35°C. The enzyme activity was inhibited strongly by Zn2+, Hg2+ and Cu2+ and moderately by Ba2+, Fe2+, Pb2+ and Ni2+. Other metal ions Ca2+, Mg2+, Co2+, Mn2+ and EDTA had almost no effect. 相似文献
999.
Muhammad Hamayun Sumera Afzal Khan Mir Ajab Khan Abdul Latif Khan Sang-Mo Kang Sang-Kuk Kim Gil-Jae Joo In-Jung Lee 《World journal of microbiology & biotechnology》2009,25(10):1785-1792
Fungal endophytes produce a variety of favorable metabolites for plant growth and survival, but there is limited information
on their gibberellin (GA) production capacity. In the current study, we isolated eight endophytic fungi from the roots of
a drought stressed soybean cultivar Hwangkeumkong, and screened them on waito-c rice for plant growth promotion. Seven fungal
isolates promoted plant growth, while one inhibited it. The culture filtrate (CF) of fungal isolate HK-5-2 provided the best
results for growth promotion and was thus bioassayed on soybean. HK-5-2 CF enhanced plant length, plant fresh and dry weight
and endogenous bioactive GA1 and GA4 contents of soybean as compared to control. The GA analysis of HK-5-2 CF showed the presence of bioactive GA3 (8.38 ng/ml), GA4 (2.16 ng/ml) and GA7 (1.56 ng/ml) in conjunction with physiologically inactive GA5, GA19 and GA24. Gibberella fujikuroi was used as positive control during this experiment. The fungal isolate HK-5-2 was identified as a new strain of Aspergillus fumigatus through molecular and phylogenetic analysis of 18S and 28S rDNA sequences. 相似文献
1000.
Ali Manafi Jamshid Kohanteb Davood Mehrabani Aziz Japoni Masoud Amini Mohsen Naghmachi Ahmad Hosseinzadeh Zaghi Nazanin Khalili 《BMC microbiology》2009,9(1):23-5