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71.

Background

In this study, a hybrid treatment system (Fluidized Bed positioned in a biological reactor of an Activated Sludge process) was used to treat saline domestic wastewater. The performance of the mentioned hybrid system was compared with the conventional activated sludge. A pilot study was conducted, and Chemical Oxygen Demand (COD), Electrical Conductivity (EC), Total Dissolved Solids (TDS) and pH were measured to investigate treatment efficiency. Three saline wastewater samples with salt concentrations of 0.5, 1, and 1.5 % and detention times of 2, 4 and 6 h were loaded into both rectors of hybrid system and activated sludge.

Results

The results showed that Chemical Oxygen Demand (COD) removals at salt concentrations of 0.5, 1, 1.5 % were equal to 80, 71, 48.5 for the hybrid system and 62, 47.7, 26.5 for the activated sludge system respectively. Likewise, similar results obtained for other contamination indices indicating the superiority of the hybrid system in comparison to activated sludge system. Moreover, another advantage of the hybrid system was that the activated sludge needed sludge returning while sludge returning was not required in the hybrid system. In addition, by loading fixed rate of air into both systems, dissolved oxygen concentration in the hybrid reactor is higher than the conventional reactor.

Conclusions

Therefore, the hybrid system had a significantly higher efficiency than conventional reactor to treat saline domestic wastewater.
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72.
73.

Background

The objective of this trial was to determine the effectiveness of 1.0% C31G (SAVVY) in preventing male-to-female vaginal transmission of HIV infection among women at high risk.

Methodology/Principal Findings

This was a Phase 3, double-blind, randomized, placebo-controlled trial. Participants made up to 12 monthly follow-up visits for HIV testing, adverse event reporting, and study product supply. The study was conducted between September 2004 and December 2006 in Lagos and Ibadan, Nigeria, where we enrolled 2153 HIV-negative women at high risk of HIV infection. Participants were randomized 1∶1 to SAVVY or placebo. The effectiveness endpoint was incidence of HIV infection as indicated by detection of HIV antibodies in oral mucosal transudate (rapid test) or blood (ELISA), and confirmed by Western blot or PCR testing. We observed 33 seroconversions (21 in the SAVVY group, 12 in the placebo group). The Kaplan-Meier estimates of the cumulative probability of HIV infection at 12 months were 0.028 in the SAVVY group and 0.015 in the placebo group (2-sided p-value for the log-rank test of treatment effect 0.121). The point estimate of the hazard ratio was 1.7 for SAVVY versus placebo (95% confidence interval 0.9, 3.5). Because of lower-than-expected HIV incidence, we did not observe the required number of HIV infections (66) for adequate power to detect an effect of SAVVY. Follow-up frequencies of adverse events, reproductive tract adverse events, abnormal pelvic examination findings, chlamydial infections and vaginal infections were similar in the study arms. No serious adverse event was attributable to SAVVY use.

Conclusions/Significance

SAVVY did not reduce the incidence of HIV infection. Although the hazard ratio was higher in the SAVVY than the placebo group, we cannot conclude that there was a harmful treatment effect of SAVVY.

Trial Registration

ClinicalTrials.gov NCT00130078  相似文献   
74.
The antineoplastic effects of 5-hydroxytryptamine (5-HT) receptor antagonists have been shown in previous studies. However, the exact underlying mechanisms mediating these antineoplastic effects are unclear. In the present study, we assessed the antineoplastic effects of tropisetron, a 5-HT receptor antagonist, in an experimental model of lung cancer in BALB/c mouse. Lewis lung carcinoma cell line was used to induce lung cancer. Mice were divided into four groups (n = 6) as follows: tumor-bearing mice + tropisetron (5 mg/kg intraperitoneally [IP]), tumor-bearing mice + tropisetron (10 mg/kg IP), tumor-bearing mice + saline, healthy mice + tropisetron (10 mg/kg). Tumor burden, interferon-γ (IFN-γ), interleukin (IL)-4, pathological response, Ki-67, and E-cadherin were assessed using enzyme-linked immunosorbent assay, and real-time polymerase chain reaction. Comet assay was used to assess DNA toxicity. Tropisetrone-treated animals (either 5 or 10 mg/kg) showed significantly lower tumor sizes at the day 24th after tumor induction. Tropisetron received animals also showed significantly higher levels of IFN-γ, E-cadherin, pathologic response, and necrotic cells compared to the saline-treated counterparts. In addition, the levels of IL-4, and Ki-67 were significantly lower in tropisetrone treated mice in comparison with control. Furthermore, tropisteron coadministration signifcantly reduced H2O2-induced DNA toxicity while treatment with tropisteron alone showed no adverse effect on DNA. Tropisetrone can be used as a potential antineoplastic drug in lung cancer. This agent can promote its antineoplastic effects in part through modulating inflammatory and proliferating markers.  相似文献   
75.
Background:Current cancer treatments include surgery, radiotherapy, chemotherapy, and immunotherapy. Despite these treatments, a main issue in cancer treatment is early detection. microRNAs (miRNAs) can be used as markers to diagnose and treat cancers. This study investigated the effect of radiotherapy on miR-374 expression, and APC and GSK-3β, two of its target genes, in the WNT pathway, in peripheral blood samples from radiotherapy-treated colorectal cancer (CRC) patients. Methods:Peripheral blood was collected from 25 patients before and after radiotherapy. RNA was extracted from the blood and cDNA synthesized. miR-374, APC, and GSK-3β expression was determined by real-time polymerase chain reaction (RT-PCR) and the amplicons were sequenced. Finally, the data were statistically evaluated.Results:Quantitative RT-PCR revealed significant down-regulation of miR-374 (0.63-fold) and up-regulation of APC (1.12-fold) and GSK-3β (1.22-fold) in CRC patients after five weeks of radiotherapy. Sequencing of PCR-produced amplicons confirmed the conservation of mature and precursor sequences encoding miR-374. miR-374 expression changed with time after radiotherapy treatment and related tumor grading. Increased age and tumor grade positively correlated with decreased miR-374 expression.Conclusion:miR-374 expression, and that of its two target genes, APC and GSK-3β, changed after radiotherapy. These genes can likely be used as diagnostic radiotherapy markers in CRC.Key Words: Biomarker, Colorectal cancer, Mir-374, Radiotherapy  相似文献   
76.
Genetic parameters for growth, mortality and reproductive performances of Markhoz goats were estimated from data collected during 1993–2010 at Markhoz goat Performance Testing Station in Sanandaj, Iran. For kid performance traits 3763 records were available for birth weight (BW), 2931 for weaning weight (WW), average daily gain (ADG) and Kleiber ratio (KR) (approximated as ADW/WW0.75) and 3032 for pre-weaning mortality (PWM). For doe reproductive performance traits there were 2920 records available for litter size at birth (LSB), litter size at weaning (LSW), total litter weight at birth (TLWB) and litter mean weight per kid born (LMWKB), and 2182 for total litter weight at weaned (TLWW) and litter mean weight per kid weaned (LMWKW). Genetic parameters were estimated with univariate and bivariate models using restricted maximum likelihood (REML) procedures. Random effects were explored by fitting additive direct genetic effects, maternal additive genetic effects, maternal permanent environmental effects, the covariance between direct and maternal genetic effects, and common litter effects in different models for pre-weaning traits of kids. Also, in addition to an animal model, sire and threshold models, using a logit link function, were used for analyses of PWM. Models for LSB, LSW, TLWB, TLWW, LMWKB, and LMWKW included direct additive genetic effects, permanent environmental effects due to the animal as well as service sire effects. Estimated direct heritabilities were moderate for pre-weaning traits (0.22 for BW, 0.16 for WW, 0.21 for ADG, and 0.27 for KR and 0.29 for PWM), and low for reproduction traits (0.01 for LSB, 0.01 for LSW, 0.02 for TLWB, 0.03 for TLWW, 0.07 for LMWKB, and 0.06 for LMWKW). The estimates for the maternal additive genetic variance ratios were lower than direct heritability for BW (0.07) and KR (0.04). The estimate for the maternal permanent environmental variance ratios (c2) varied from 0.01 for KR to 0.07 for WW and ADG. The magnitude of common litter variance ratios (l2) was more substantial for BW (0.46) than the PWM (0.19) and KR (0.16). The estimate for the permanent environmental variance due to the animal (c2) ranged from 0.03 for LMWKB to 0.07 for TLWB and LMWKW, whereas service sire effects (s2) ranged from 0.02 to 0.04. The correlation between direct and maternal genetic effects were negative and high for BW (?0.51) and KR (?0.62). The genetic correlations between pre-weaning growth traits were positive and moderate to strong, as were genetic correlations between reproductive traits. Between BW and PWM the correlation was ?0.35. Phenotypic and environmental correlations for all traits were generally lower than genetic correlations.  相似文献   
77.
In the current article, a combination of the differential transform method (DTM) and Padé approximation method are implemented to solve a system of nonlinear differential equations modelling the flow of a Newtonian magnetic lubricant squeeze film with magnetic induction effects incorporated. Solutions for the transformed radial and tangential momentum as well as solutions for the radial and tangential induced magnetic field conservation equations are determined. The DTM-Padé combined method is observed to demonstrate excellent convergence, stability and versatility in simulating the magnetic squeeze film problem. The effects of involved parameters, i.e. squeeze Reynolds number (N 1), dimensionless axial magnetic force strength parameter (N 2), dimensionless tangential magnetic force strength parameter (N 3), and magnetic Reynolds number (Re m) are illustrated graphically and discussed in detail. Applications of the study include automotive magneto-rheological shock absorbers, novel aircraft landing gear systems and biological prosthetics.  相似文献   
78.
Effects of vitamin E and selenium supplementation on aldehyde oxidase (AO) and xanthine oxidase (XO) activities and antioxidant status in liver, kidney, and heart of streptozotocin (STZ)-induced diabetic rats were examined. AO and XO activities increased significantly after induction of diabetes in rats. Following oral vitamin E (300 mg/kg) and sodium selenite (0.5 mg/kg) intake once a day for 4 weeks, XO activity decreased significantly. AO activity decreased significantly in liver, but remained unchanged in kidney and heart of vitamin E- and selenium-treated rats compared to the diabetic rats. Total antioxidants status, paraoxonase-1 (PON1) and erythrocyte superoxide dismutase activities significantly decreased in the diabetic rats compared to the controls, while a higher fasting plasma glucose level was observed in the diabetic animals. The glutathione peroxidase activity remained statistically unchanged. Malondialdehyde and oxidized low-density lipoprotein levels were higher in the diabetic animals; however, these values were significantly reduced following vitamin E and selenium supplementation. In summary, both AO and XO activities increase in STZ-induced diabetic rats, and vitamin E and selenium supplementation can reduce these activities. The results also indicate that administration of vitamin E and selenium has hypolipidemic, hypoglycemic, and antioxidative effects. It decreases tissue damages in diabetic rats, too.  相似文献   
79.
Autonomic dysfunction is frequent in patients with fibromyalgia (FM). Heart rate variability analyses have demonstrated signs of ongoing sympathetic hyperactivity. Catecholamines are sympathetic neurotransmitters. Catechol-O-methyltransferase (COMT), an enzyme, is the major catecholamine-clearing pathway. There are several single-nucleotide polymorphisms (SNPs) in the COMT gene associated with the different catecholamine-clearing abilities of the COMT enzyme. These SNPs are in linkage disequilibrium and segregate as 'haplotypes'. Healthy females with a particular COMT gene haplotype (ACCG) producing a defective enzyme are more sensitive to painful stimuli. The objective of our study was to define whether women with FM, from two different countries (Mexico and Spain), have the COMT gene haplotypes that have been previously associated with greater sensitivity to pain. All the individuals in the study were female. Fifty-seven Mexican patients and 78 Spanish patients were compared with their respective healthy control groups. All participants filled out the Fibromyalgia Impact Questionnaire (FIQ). Six COMT SNPs (rs2097903, rs6269, rs4633, rs4818, rs4680, and rs165599) were genotyped from peripheral blood DNA. In Spanish patients, there was a significant association between three SNPs (rs6269, rs4818, and rs4680) and the presence of FM when compared with healthy controls. Moreover, in Spanish patients with the 'high pain sensitivity' haplotype (ACCG), the disease, as assessed by the FIQ, was more severe. By contrast, Mexican patients displayed only a weak association between rs6269 and rs165599, and some FIQ subscales. In our group of Spanish patients, there was an association between FM and the COMT haplotype previously associated with high pain sensitivity. This association was not observed in Mexican patients. Studies with a larger sample size are needed in order to verify or amend these preliminary results.  相似文献   
80.

Introduction

Esophageal intramural pseudodiverticulosis is a rare condition characterized by the dilatation of the submucosal glands.

Case presentation

We present a case of esophageal intramural pseudodiverticulosis in a 72-year-old Caucasian man who presented with dysphagia and with a background history of alcohol abuse. An upper gastrointestinal endoscopy of our patient showed an esophageal stricture with abnormal mucosal appearances, but no malignant cells were seen at biopsy. Appearances on a barium esophagram were pathognomonic for esophageal intramural pseudodiverticulosis.

Conclusion

We demonstrate the enduring usefulness of barium esophagography in the characterization of abnormal mucosal appearances at endoscopy.  相似文献   
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