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141.
142.
The present study aimed to predict differential enrichment of pathways and compounds in the rhizosphere microbiomes of the two wild plants (Abutilon fruticosum and Nitrosalsola vermiculata) and to predict functional shifts in microbiomes due to water. Amplicon sequencing of 16S rRNA region V3–V4 was done and gene-based microbial compositions were enrolled in PICRUSt to predict enriched pathways and compounds. The results indicated that “ABC transporters” and “Quorum sensing” pathways are among the highest enriched pathways in rhizosphere microbiomes of the two wild plants compared with those of the bulk soil microbiomes. The highest enriched compounds in soil microbiomes of the two wild plants included five proteins and three enzymes participating in one or more KEGG pathways. Six of these eight compounds showed higher predicted enrichment in rhizosphere soil microbiomes, while only one, namely phosphate transport system substrate-binding protein, showed higher enrichment in the surrounding bulk soil microbiomes. In terms of differentially enriched compounds due to watering, only the dual-specific aspartyl-tRNA (Asn)/glutamyl-tRNA (Gln) amidotransferase subunit A showed higher enrichment in rhizosphere soil of the two wild plants after 24 h of watering. Two of the highly enriched compounds namely branched-chain amino acid transport system ATP-binding protein and branched-chain amino acid transport system substrate-binding protein, are encoded by genes stimulated by the plant’s GABA that participates in conferring biotic and abiotic stresses in plants and improves the plant’s growth performance. The 3-Oxoacyl-[ACP] reductase, a member of the short-chain alcohol dehydrogenase/ reductase (SDR) superfamily, participates in fatty acids elongation cycles and contributes to plant-microbe symbiotic relationships, while enoyl-CoA hydratase has a reverse action as it participates in “Fatty acid degradation” pathway. The methyl-accepting chemotaxis protein is an environmental signal that sense “Bacterial chemotaxis” pathway to help establishing symbiosis with plant roots by recruiting/colonizing of microbial partners (symbionts) to plant rhizosphere. This information justifies the high enrichment of compounds in plant rhizosphere. The dual-specific aspartyl-tRNA (Asn)/glutamyl-tRNA (Gln) amidotransferase subunit A contributes to the plant ability to respond to watering as it participates in attaching the correct amino acid during translation to its cognate tRNA species, while hydrolyzing incorrectly attached amino acid. These two actions reduce the influence of oxidative stress in generating misfolded proteins and in reducing fidelity of translation.  相似文献   
143.
Toxoplasmosis is considered as an important risk factor for bad obstetric history (BOH) and one of the major causes of congenitally acquired infections. The present study aimed to estimate the seropositivity of T. gondii infection and associated risk factors among the attendees of high risk pregnancy and low risk antenatal care clinic of Minia Maternity and Pediatric University Hospital, Minia, Egypt. The study was carried out from April 2013 to April 2014 through 2 phases, the first phase was case-control study, and the second phase was follow-up with intervention. A total of 120 high risk pregnant and 120 normal pregnant females were submitted to clinical examinations, serological screening for anti-Toxoplasma IgM and IgG antibodies by ELISA, and an interview questionnaire. Seropositive cases were subjected to spiramycin course treatment. The results showed that the seroprevalence of toxoplasmosis in high-risk pregnancy group was 50.8%, which was significantly different from that of normal pregnancy group (P<0.05). Analysis of seropositive women in relation to BOH showed that abortion was the commonest form of the pregnancy wastage (56.5%). The high prevalence of T. gondii seropositive cases was observed in the age group of 21-30 years. Post-delivery adverse outcome was observed in 80.3% of high-risk pregnancy group compared to 20% of normal pregnancy group. There was a statistically significant relationship between seropositivity and living in rural area, low socioeconomic level, and undercooked meat consumption (P<0.05). Serological screening for anti-Toxoplasma antibodies should be routine tests especially among high-risk pregnant women.  相似文献   
144.
Apoptosis is the primary mechanism through which most chemotherapeutic agents induce tumor cell death. The purpose of this study was to monitor the expression of pro- and anti-apoptotic proteins CD(95) , Bcl-2, as well as copper and zinc levels in the peripheral blood of children with acute lymphocytic leukemia (ALL) prior to and 6 months after the beginning of chemotherapy. Blood parameters and bone marrow blast count were also assessed. Twenty of 26 patients who received treatment showed amelioration in apoptotic response, which is reflected in the elevation of CD(95) , whereas Bcl-2 protein was significantly lowered. In these patients, the elevated serum copper level was not significantly affected whereas the low serum zinc level was significantly raised. Improvement in blood parameters and bone marrow blast count were also achieved. Taken together, the data suggested that assessment of apoptosis signaling molecules might have a predictive impact on treatment outcome.  相似文献   
145.
This work has been carried out to investigate the effect of Schistosoma mansoni infection on mice livers after treatment with the ethanolic extract of Citrus reticulata root or the oleo-resin extract from Myrrh of Commiphora molmol tree (Mirazid), as a new antishistosomal drug. Marker enzymes for different cell organelles were measured; succinate dehydrogenase (SDH); lactate dehydrogenase (LDH) and its isoenzymes; glucose-6-phosphatase (G-6-Pase); acid phosphatase (AP) and 5'- nucleotidase. Liver function enzymes; aspartate aminotransferase (AST); alanine aminotransferase (ALT), and alkaline phosphatase (ALP) were also estimated. Parasitological studies through ova count and worm burden will also be taken into consideration. The results showed a marked reduction in SDH, LDH, AST, and ALT enzyme activities and a significant increase in G-6-Pase, AP, 5'- nucleotidase, and ALP after S. mansoni infection. A noticeable alteration in LDH subunits were also noticed. Treatment with C. reticulata or Mirazid improved all the previous enzyme activities with a noticeable reduction in ova count and worm burden.  相似文献   
146.
Glucose is the preferred carbon and energy source in prokaryotes, unicellular eukaryotes, and metazoans. However, excess of glucose has been associated with several diseases, including diabetes and the less understood process of aging. On the contrary, limiting glucose (i.e., calorie restriction) slows aging and age-related diseases in most species. Understanding the mechanism by which glucose limits life span is therefore important for any attempt to control aging and age-related diseases. Here, we use the yeast Schizosaccharomyces pombe as a model to study the regulation of chronological life span by glucose. Growth of S. pombe at a reduced concentration of glucose increased life span and oxidative stress resistance as reported before for many other organisms. Surprisingly, loss of the Git3 glucose receptor, a G protein-coupled receptor, also increased life span in conditions where glucose consumption was not affected. These results suggest a role for glucose-signaling pathways in life span regulation. In agreement, constitutive activation of the Gα subunit acting downstream of Git3 accelerated aging in S. pombe and inhibited the effects of calorie restriction. A similar pro-aging effect of glucose was documented in mutants of hexokinase, which cannot metabolize glucose and, therefore, are exposed to constitutive glucose signaling. The pro-aging effect of glucose signaling on life span correlated with an increase in reactive oxygen species and a decrease in oxidative stress resistance and respiration rate. Likewise, the anti-aging effect of both calorie restriction and the Δgit3 mutation was accompanied by increased respiration and lower reactive oxygen species production. Altogether, our data suggest an important role for glucose signaling through the Git3/PKA pathway to regulate S. pombe life span.  相似文献   
147.
Focus on the development of botanical insecticides such as polyphenols may represent an alternative method to chemical control. In the present study, total glutathione concentration and its related antioxidant enzymes in foregut, midgut, hindgut and fat body homogenates of the desert locust Schistocerca gregaria are examined. Glutathione S‐transferase (GST) activity exhibits a significantly higher value in fat bodies compared with other tissues. A simple and reproducible procedure for the purification of S. gregaria fat body GST is established and the purified enzyme is shown to be homogenous. The purified GST displays a typical Michaelis behaviour with respect to its substrates. Characterization of the GST, including optimum pH, substrate specificity and inhibitor effects, is carried out. The ability of some flavonoids to inhibit S. gregaria fat body GST activity is examined. High‐performance liquid chromatography analysis indicates that the major components in Glycyrrhiza glabra roots are 18α‐glycyrrhetinic acid, quercetin and rutin, and the major components in Hibiscus sabdariffa calyx are cyanidin 3‐O‐glucoside chloride and delphinidin. Quercetin and delphinidin chloride exhibit strong GST inhibition and the inhibition type is determined for both. Rutin shows a smaller inhibitory effect, whereas 18α‐glycyrrhetinic acid and cyanidin have no effect. Inhibition of S. gregaria fat body GST activity would be expected to prevent, or at least delay, the development of resistance to chemical pesticides. Among the examined levels of the antioxidant enzymes, total glutathione concentration and its related enzymes in foregut, midgut, hindgut and fat body crude homogenates of S. gregaria GST activity exhibit a significantly higher value in fat bodies compared with other tissues. Some flavonoids that are detected in H. sabdariffa calyx and G. glabra root extracts are the most effective inhibitors of the purified S. gregaria fat body GST activity. Inhibition of S. gregaria fat body GST activity by quercetin and delphinidin (major compounds detected by HPLC) would be expected to prevent, or at least delay, the development of resistance to chemical pesticides.  相似文献   
148.
Strains of Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Enterococcus faecalis, and Klebsiella pneumoniae, mostly from complicated urinary tract infections, showed reduced adherence to silver-treated silicone or latex catheters as compared with latex or silicone catheters. The relative degrees of cell adherence to catheters at 2 h or 18 h, as indicated by radiolabeled cell assays, were in general agreement with growth rate-reduction assays and scanning-electron-microscopy data. For strains of E. coli, the correlation between cell hydrophobicity and degree of adherence to catheters was not significant. Antibiotic resistance (tetracycline, sulfathiazine, neomycin, kanamycin) and silver resistance were not associated. The radiolabel adherence procedure provided a quantitative method for evaluating the relative antimicrobial efficacy of silver-treated catheters.  相似文献   
149.
150.
This study investigated the application of Potamogeton pectinatus for Ni(II)-ions biosorption from aqueous solutions. FTIR spectra showed that the functional groups of –OH, C–H, –C = O, and –COO– could form an organometallic complex with Ni(II)-ions on the biomaterial surface. SEM/EDX analysis indicated that the voids on the biosorbent surface were blocked due to Ni(II)-ions uptake via an ion exchange mechanism. For Ni(II)-ions of 50 mg/L, the adsorption efficiency recorded 63.4% at pH: 5, biosorbent dosage: 10 g/L, and particle-diameter: 0.125–0.25 mm within 180 minutes. A quadratic model depicted that the plot of removal efficiency against pH or contact time caused quadratic-linear concave up curves, whereas the curve of initial Ni(II)-ions was quadratic-linear convex down. Artificial neural network with a structure of 5 – 6 – 1 was able to predict the adsorption efficiency (R2: 0.967). The relative importance of inputs was: initial Ni(II)-ions > pH > contact time > biosorbent dosage > particle-size. Freundlich isotherm described well the adsorption mechanism (R2: 0.974), which indicated a multilayer adsorption onto energetically heterogeneous surfaces. The net cost of using P. pectinatus for the removal of Ni(II)-ions (4.25 ± 1.26 mg/L) from real industrial effluents within 30 minutes was 3.4 $USD/m3.  相似文献   
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