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961.

The primary aim of our study was to determine the influence of taking chromium plus carnitine on insulin resistance, with a secondary objective of evaluating the influences on lipid profiles and weight loss in overweight subjects with polycystic ovary syndrome (PCOS). In a 12-week randomized, double-blind, placebo-controlled clinical trial, 54 overweight women were randomly assigned to receive either supplements (200 μg/day chromium picolinate plus 1000 mg/day carnitine) or placebo (27/each group). Chromium and carnitine co-supplementation decreased weight (− 3.6 ± 1.8 vs. − 1.0 ± 0.7 kg, P < 0.001), BMI (− 1.3 ± 0.7 vs. − 0.3 ± 0.3 kg/m2, P < 0.001), fasting plasma glucose (FPG) (− 5.1 ± 6.0 vs. − 1.1 ± 4.9 mg/dL, P = 0.01), insulin (− 2.0 ± 1.4 vs. − 0.2 ± 1.2 μIU/mL, P < 0.001), insulin resistance (− 0.5 ± 0.4 vs. − 0.04 ± 0.3, P < 0.001), triglycerides (− 18.0 ± 25.2 vs. + 5.5 ± 14.4 mg/dL, P < 0.001), total (− 17.0 ± 20.3 vs. + 3.6 ± 12.0 mg/dL, P < 0.001), and LDL cholesterol (− 13.3 ± 19.2 vs. + 1.4 ± 13.3 mg/dL, P = 0.002), and elevated insulin sensitivity (+ 0.007 ± 0.005 vs. + 0.002 ± 0.005, P < 0.001). In addition, co-supplementation upregulated peroxisome proliferator-activated receptor gamma (P = 0.02) and low-density lipoprotein receptor expression (P = 0.02). Overall, chromium and carnitine co-supplementation for 12 weeks to overweight women with PCOS had beneficial effects on body weight, glycemic control, lipid profiles except HDL cholesterol levels, and gene expression of PPAR-γ and LDLR. Clinical trial registration number: http://www.irct.ir: IRCT20170513033941N38.

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962.
Complications of chemotherapy, such as appearance of multidrug resistance, have persuaded researchers to consider phage therapy as a new method to combat bacterial infections. In vitro experiments were performed to assess the therapeutic value of genetically modified phages for controlling gastrointestinal Escherichia coli O157:H7 cells in Luria–Bertani (LB) media and contaminated cow milk. We constructed a modified nonreplicating M13-derived phage expressing a lethal catabolite gene activator protein (CAP) that is a Glu181Gln mutant of CAP. The modified phagemid was propagated in the lethal CAP-resistant strain XA3DII. Time–kill assay experiments showed a considerable reduction in the number of surviving bacteria in both LB media and contaminated cow milk. Our further study using other test strains demonstrated that the host range of lethal phage is limited to E. coli strains that produce pili. This study provides a possible strategy for the exploitation of genetically engineered nonlytic phages as bactericidal agents by minimizing the risk of release of progeny phages and endotoxins into the environment. The phage was engineered to remain lethal to its bacterial target, but incapable of replicating therein. Furthermore, the addition of an inducer to express the lethal protein is not required.  相似文献   
963.
Streptomyces parvulus was used as the recipient for plasmid pIJ303 and pIJ211, two conjugative plasmids derived from the self-transmissible plasmid pIJ101. One of the resulting transconjugantS. parvulus strains containing plasmid pIJ303 was used withS. lividans to evaluate the effects of the host strain on the frequency of pIJ303 transfer betweenStreptomyces species. Only 30% ofS. parvulus cells acquired plasmid pIJ303 in crosses in whichS. lividans was the donor, whereas 100% ofS. lividans cells acquired the plasmid whenS. parvulus was the donor. This indicates that the frequency of transfer of the conjugative plasmid was determined by the recipient. The other resulting transconjugantS. parvulus strain containing plasmid pIJ211 was evaluated for its ability to mobilize the nonconjugative plasmid pIJ702 fromS. lividans, on agar and in sterile soil. AfterS. lividans containing pIJ702 was crossed on agar and in sterile soil withS. parvulus containing pIJ211, recombinantS. parvulus colonies carrying pIJ702 and expressing pigments characteristic of both species were recovered, from both agar and soil. Although a large percentage ofS. parvulus transconjugants lost pIJ211 during incubation in soil, the mobilization of pIJ702 fromS. lividans intoS. parvulus still occurred. Plasmid integration into the chromosome of the donor and the transconjugant was evaluated by Southern blot hybridization. Hybridization of plasmid pIJ303, with chromosomal DNA fromS. lividans andS. parvulus transconjugants, using biotinylated DNA, indicated that no integration had occurred. Genetic exchange betweenStreptomyces species also occurred in a liquid medium. The finding of plasmid mobilization in soil is significant. It demonstrates that genetic exchange in the environment can occur between released genetically engineeredStreptomyces species and nativeStreptomyces species that contain conjugative plasmids.Paper of the Idaho Agricultural Experiment Station.  相似文献   
964.
965.
Attention-deficit/hyperactivity disorder (ADHD) is considered to be the most prevalent disorder of childhood and adolescence, and a variety of methods have been used in its diagnosis and treatment. This study was conducted to study the efficacy of play therapy on the symptoms of ADHD in children aged 7–9 years. Using a clinical trial design, we selected 30 study participants among individuals who had been referred to the Ebne-sina hospital, child and adolescent outpatient clinic, Mashhad, Iran, and who had been diagnosed with ADHD by psychiatrists. The 30 study participants were then divided into two groups, experimental and control, based on similar characteristics (Birth order, parents’ educational level, parents’ occupation and average of last year school marks). Pre-tests (the Rutter Parental Questionnaire and the Rutter Children Behaviour Questionnaire for teachers) were performed prior to play therapy, and all patients in both groups had been receiving medication. Following play therapy, post-tests were also conducted for both groups. Eight sessions of sham play therapy has been performed for case group. (Cognitive-behavioural play therapy has not been performed basically.) All results were evaluated using an independent t test and a comparative test. Play therapy appeared to significantly reduce the symptoms of ADHD. The significant differences found between the experimental and control groups indicate that play therapy could be used as an effective treatment method for children with ADHD.  相似文献   
966.
Biodiesel production from microalgae feedstock should be performed after growth and harvesting of the cells, and the most feasible method for harvesting and dewatering of microalgae is flocculation. Flocculation modeling can be used for evaluation and prediction of its performance under different affective parameters. However, the modeling of flocculation in microalgae is not simple and has not performed yet, under all experimental conditions, mostly due to different behaviors of microalgae cells during the process under different flocculation conditions. In the current study, the modeling of microalgae flocculation is studied with different neural network architectures. Microalgae species, Chlorella sp., was flocculated with ferric chloride under different conditions and then the experimental data modeled using artificial neural network. Neural network architectures of multilayer perceptron (MLP) and radial basis function architectures, failed to predict the targets successfully, though, modeling was effective with ensemble architecture of MLP networks. Comparison between the performances of the ensemble and each individual network explains the ability of the ensemble architecture in microalgae flocculation modeling.  相似文献   
967.
Background

Insulin resistance as a major problem is associated with type 2 diabetes mellitus. This study investigated the effect of Eryngium billardierei on insulin-resistance induced HepG2 cells.

Methods and results

MTT method was used to evaluate the viability of HepG2 cells treated with various doses of E. billardierei extract. An insulin-resistance model was established in HepG2 cells. Next, MTT assay and Acridine orange staining were performed to investigate the viability of cells in the vicinity of different concentrations of insulin, pioglitazone, and E. billardierei extract in an insulin-resistance media. The glucose uptake test was performed to select the optimal insulin concentration. Expression levels of IR, G6Pase, and PEPCK genes were assessed by real-time RT-PCR. According to obtained data, E. billardierei at concentrations of 0.5 and 1 mg/mL show no toxicity on cells. Furthermore, based on MTT assay and glucose uptake test 10?5 mol/L insulin was chosen as the model group to induce insulin-resistance in HepG2 cells for gene expression analysis. Finally, 1 mg/mL E. billardierei not only induced no cytotoxicity but also showed an increase in the expression of IR as well as a reduction in G6Pase and PEPCK level compared to the control and model groups.

Conclusions

The obtained data indicated that 1 mg/mL E. billardierei might have an anti-insulin resistance effect on insulin-resistance HepG2 cells in vitro and could be a promising candidate with anti-hyperglycemic properties for diabetes treatments.

Graphical abstract
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968.
Recent comprehensive assessments of RNA-seq technology support its utility in quantifying gene expression in various samples. The next step of rigorously quantifying differences between sample groups, however, still lacks well-defined best practices. Although a number of advanced statistical methods have been developed, several studies demonstrate that their performance depends strongly on the data under analysis, which compromises practical utility in real biomedical studies. As a solution, we propose to use a data-adaptive procedure that selects an optimal statistic capable of maximizing reproducibility of detections. After demonstrating its improved sensitivity and specificity in a controlled spike-in study, the utility of the procedure is confirmed in a real biomedical study by identifying prognostic markers for clear cell renal cell carcinoma (ccRCC). In addition to identifying several genes previously associated with ccRCC prognosis, several potential new biomarkers among genes regulating cell growth, metabolism and solute transport were detected.  相似文献   
969.
Protoplasma - In the current study the role of H2O2 in He–Ne laser-induced effects on seed germination and post-germinative performance of Salvia officinalis seedlings was assessed under both...  相似文献   
970.
Dealing with nude mice, which lack thymus and therefore are sensitive to unsterile conditions, needs special care and laboratory conditions. For preclinical studies, especially tumour imaging purposes, in which therapeutic properties of drugs or therapeutic compounds are not studied, mice with normal immune system can be a favourable alternative if they carry tumours of interest. In the current study, we introduce an optimized protocol for induction of human tumours in BALB/c mice for preclinical studies. Immune system of BALB/c mice was suppressed by administration of cyclosporine A (CsA), ketoconazole and cyclophosphamide. The tumours of MDA-MB-231, A-431 and U-87-MG human cancer cells were induced by subcutaneous injection of the cells to the immunosuppressed mice. Tumour size was calculated weekly. Histopathological and metastatic analyses were performed using haematoxylin and eosin staining. The combination of the three drugs was found to suppress immune system and decrease the numbers of white blood cells, including lymphocytes. At the eighth week, tumours with a dimension of approximately 1400 mm3 developed. Large atypical nuclei with scant cytoplasm were found to exist using histopathological analysis. No metastasis was observed in the tumour-bearing mice. A combination of CsA, ketoconazole and cyclophosphamide can be used to suppress the immune system in BALB/c mice and induce tumours with significant size.  相似文献   
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