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111.
Moutaouakkil A Zeroual Y Zohra Dzayri F Talbi M Lee K Blaghen M 《Archives of biochemistry and biophysics》2003,413(1):139-146
Azoreductase, an enzyme catalyzing the reductive cleavage of the azo bond of methyl red (MR) and related dyes, was purified to electrophoretic homogeneity from Enterobacter agglomerans. This bacterial strain, isolated from dye-contaminated sludge, has a higher ability to grow, under aerobic conditions, on culture medium containing 100mg/L of MR. The enzyme was purified approximately 90-fold with 20% yield by ammonium sulfate precipitation, followed by three steps of column chromatography (gel-filtration, anion-exchange, and dye-affinity). The purified enzyme is a monomer with a molecular weight of 28,000 Da. The maximal azoreductase activity was observed at pH 7.0 and at 35 degrees C. This activity was NADH dependent. The K(m) values for both NADH and MR were 58.9 and 29.4 microM, respectively. The maximal velocity (V(max)) was 9.2 micromol of NADH min(-1)mg(-1). The purified enzyme is inhibited by several metal ions including Fe(2+) and Cd(2+). 相似文献
112.
Shabnam Asfaram Saeed Hosseini Teshnizi Mahdi Fakhar Elham Sadat Banimostafavi Masoud Soosaraei 《Parasitology international》2018,67(5):575-583
Visualization of amastigotes in lymph nodes, bone marrow, and other tissues samples remains the gold standard method for the diagnosis of visceral leishmaniasis (VL) in humans. This gold standard diagnostic method uses a technically challenging microscopy procedure that is often not accessible in many places in the world where VL is endemic. Here, we report the current systematic review and meta-analysis to evaluate whether urine is a reliable clinical sample for diagnosis of human VL. Data were extracted from ten available databases during the period from 2002 to 2017. Overall, 29 articles fulfilled the inclusion criteria and were used for data extraction in this systematic review. Most studies (72.4%) using urine specimens were reported from five countries: India 6 (20.7%), Iran 5 (17.2%), Bangladesh 4 (13.8%), Japan 3 (10.3%) and Spain 3 (10.3%), respectively. The most common diagnostic tests performed on urine were Katex (62.1%), ELISA (24.1%), and the rK39 (17.2%) assays. In meta-analysis the sensitivity and specificity of the three most commonly used diagnostic assays were rK39 (97%; CI: 91–99; 98%;76–100), ELISA (91%; 82–95; 99%; CI: 94–100), and Katex (83%; 73–90; 98%; 98–100), suggesting that the rK39 assay provided the highest sensitivity and the ELISA assay provided the highest specificity for diagnosis of VL from urine samples. Our findings suggest that urine is a valuable clinical sample for the diagnosis of human VL, particularly in areas where the gold standard test for VL is not available. 相似文献
113.
Al-Majali AM Asem EK Lamar CH Robinson JP Freeman MJ Saeed AM 《FEMS immunology and medical microbiology》2000,28(2):97-104
Enterotoxigenic Escherichia coli (ETEC) induces severe diarrhea in newborn calves through the elaboration of heat-stable enterotoxin (STa). We investigated the distribution and characteristics of the STa-specific receptors on enterocytes and brush border membrane vesicles (BBMVs) prepared from anterior jejunum, posterior jejunum, ileum and colon of newborn calves. We found that density of the receptors and their affinity to STa were higher on enterocytes and BBMVs that were derived from the ileum than enterocytes and BBMVs prepared from other segments of the calf intestine. This study suggests that, in newborn calves, the ileum is the major part of the intestinal tract that is affected in the course of secretory diarrhea caused by STa-producing ETEC strains. 相似文献
114.
Hasan Moradian Ali K. Esmailizadeh Saeed S. Sohrabi Ehsan Nasirifar Nahid Askari Mohammad Reza Mohammadabadi Amin Baghizadeh 《Molecular biology reports》2014,41(7):4455-4462
The purpose of this study was to identify genomic regions, quantitative trait loci (QTL), affecting carcass traits on chromosome 1 in an F2 population of Japanese quail. For this purpose, two white and wild strains of Japanese quail (16 birds) were crossed reciprocally and F1 generation (34 birds) was created. The F2 generation was produced by intercrossing of the F1 birds. Phenotypic data including carcass weight, internal organs and carcass parts were collected on F2 animals (422 birds). The total mapping population (472 birds) was genotyped for 8 microsatellite markers on chromosome 1. QTL analysis was performed with interval mapping method applying the line-cross model. Significant QTL were identified for breast weight at 0 (P < 0.01), 172 (P < 0.05) and 206 (P < 0.01), carcass weight at 91 (P < 0.05), carcass fatness at 0 (P < 0.01), pre-stomach weight at 206 (P < 0.01) and uropygial weight gland at 197 (P < 0.01) cM on chromosome 1. There was also evidence for imprinted QTL affecting breast weight (P < 0.01) on chromosome 1. The proportion of the F2 phenotypic variation explained by the significant additive, dominance and imprinted QTL effects ranged from 1.0 to 7.3 %, 1.2 to 3.3 % and 1.4 to 2.2 %, respectively. 相似文献
115.
Volatile Oils from the Aerial Parts of Eremophila maculata and Their Antimicrobial Activity 下载免费PDF全文
Fadia S. Youssef Razan Hamoud Mohamed L. Ashour Abdel Nasser Singab Michael Wink 《化学与生物多样性》2014,11(5):831-841
The essential oils isolated from the fresh flowers, fresh leaves, and both fresh and air‐dried stems of Eremophila maculata (Scrophulariaceae) were characterized by GC‐FID and GC/MS analyses. Sabinene was the major component in most of the oils, followed by limonene, α‐pinene, benzaldehyde, (Z)‐β‐ocimene, and spathulenol. The leaf and flower essential oils showed antibacterial and antifungal activity against five Gram‐positive and four Gram‐negative bacterial strains, multi‐resistant clinical isolates from patients, i.e., methicillin‐resistant Staphylococcus aureus (MRSA), as well as two yeasts. Minimum inhibitory concentrations (MICs) and minimum microbicidal concentrations (MMCs) were between 0.25 and 4 mg/ml. 相似文献
116.
Maltodextrins as Chiral Selectors in CE: Molecular Structure Effect of Basic Chiral Compounds on the Enantioseparation 下载免费PDF全文
Prediction of chiral separation for a compound using a chiral selector is an interesting and debatable work. For this purpose, in this study 23 chiral basic drugs with different chemical structures were selected as model solutes and the influence of their chemical structures on the enantioseparation in the presence of maltodextrin (MD) as chiral selector was investigated. For chiral separation, a 100‐mM phosphate buffer solution (pH 3.0) containing 10% (w/v) MD with dextrose equivalent (DE) of 4‐7 as chiral selector at the temperature of 25°C and voltage of 20 kV was used. Under this condition, baseline separation was achieved for nine chiral compounds and partial separation was obtained for another six chiral compounds while no enantioseparation was obtained for the remaining eight compounds. The results showed that the existence of at least two aromatic rings or cycloalkanes and an oxygen or nitrogen atom or –CN group directly bonded to the chiral center are necessary for baseline separation. With the obtained results in this study, chiral separation of a chiral compound can be estimated with MD‐modified capillary electrophoresis before analysis. This prediction will minimize the number of preliminary experiments required to resolve enantiomers and will save time and cost. Chirality 26:620–628, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
117.
The genus Sathrophyllia Stål, 1874 from Pakistan is reviewed with four species recorded. The diagnostic characters are given and two new species Sathrophyllia
saeedi
sp. n. and Sathrophyllia
irshadi
sp. n. are described. In addition to that Sathrophyllia
nr.
rugosa (Linnaeus, 1758) and Sathrophyllia
femorata (Fabricius, 1787) are re-described. Further information on the distribution and ecology of the species is given and a key to studied species of Sathrophyllia is presented. Sathrophyllia
femorata (Fabricius, 1787) and Sathrophyllia
rugosa (Linnaeus, 1758) are recorded from Rawalakot (KPK) and Tharparker (Sindh), Pakistan for first the time. 相似文献
118.
M.A. Sandhu A.A. Saeed M.S. Khilji R.H. Pasha N. Mukhtar M.S. Anjum 《European journal of histochemistry : EJH》2014,58(1)
To evaluate the subpopulation of corticotrophs in developing buffalo (Bubalus bubalis) fetus, pituitary glands were recovered (n=6 per group) from late first, second and third gestational female buffalo dams. The corticotrophs were identified by using specific antibodies against proopiomelanocortin (POMC) and adrenocorticotrophic hormone (ACTH) through immunohistochemistry. There was a significant (P≤0.05) increase of immunoreactive (ir) ir-ACTH cells during late 2nd trimester while, ir-POMC cells were more (P≤0.05) at late 3rd trimester of gestation as compared to other age groups. The quantity of co-localized cells for POMC and ACTH was significantly (P≤0.05) greater at the end of 1st gestation rather than 2nd and 3rd gestational fetal adenohypophyseal cells. This study is the first to demonstrate co-localization of POMC+ACTH and the affect of gestational age on the expression of these cells in buffalo fetus adenohypophysis.Key words: buffalo, corticotrophs, fetus, pituitary gland, immunohistochemistry 相似文献
119.
Youssef K Mack JJ Iruela-Arispe ML Bouchard LS 《Biotechnology and bioengineering》2012,109(7):1844-1854
Shear stress is an important physical factor that regulates proliferation, migration, and morphogenesis. In particular, the homeostasis of blood vessels is dependent on shear stress. To mimic this process ex vivo, efforts have been made to seed scaffolds with vascular and other cell types in the presence of growth factors and under pulsatile flow conditions. However, the resulting bioreactors lack information on shear stress and flow distributions within the scaffold. Consequently, it is difficult to interpret the effects of shear stress on cell function. Such knowledge would enable researchers to improve upon cell culture protocols. Recent work has focused on optimizing the microstructural parameters of the scaffold to fine tune the shear stress. In this study, we have adopted a different approach whereby flows are redirected throughout the bioreactor along channels patterned in the porous scaffold to yield shear stress distributions that are optimized for uniformity centered on a target value. A topology optimization algorithm coupled to computational fluid dynamics simulations was devised to this end. The channel topology in the porous scaffold was varied using a combination of genetic algorithm and fuzzy logic. The method is validated by experiments using magnetic resonance imaging readouts of the flow field. 相似文献
120.
This study was undertaken to investigate the hematological and biochemical changes in experimentally infected goats with Besnoitia caprae from the time of infection till 360 days post-infection (PI). Six male goats were inoculated subcutaneously with 13 × 10(7) bradyzoites of B. caprae, and blood samples were collected from the jugular vein. The total erythrocyte and total leukocyte counts, hematocrit value, and differential leukocyte counts were determined. Serum biochemical analysis, including the total protein, albumin, total globulin, cholesterol, triglyceride, chloride, testosterone, calcium (Ca(2+)), inorganic phosphorus, sodium (Na(+)), potassium (K(+)), iron (Fe(2+)), glucose, serum amyloid A (SAA), haptoglobin (Hp), fibrinogen, ceruloplasmin, aspartate aminotransferase, alanine aminotransferase, creatine kinase, lactate dehydrogenase, and alkaline phosphatase, was undertaken. Skin biopsy from the limbs were collected at weekly intervals and histologically examined for Besnoitia cysts. Cysts were present in the skin biopsies of the leg of the infected goats from day 28 PI. There were variations in hematological analyses, but no significant difference was seen. From day 30 to 360 PI, results showed that SAA, Hp, fibrinogen, and ceruloplasmin concentrations increased, whereas testosterone concentrations decreased. Infected goats exhibited decrease of albumin and increase of serum total protein and globulin concentrations. By contrast, there were no significant differences in the remained analyses concentrations. 相似文献