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21.
The Protein Journal - As expected, several new variants of Severe Acute Respiratory Syndrome-CoronaVirus-2 (SARS-CoV-2) emerged and have been detected around the world throughout this Coronavirus...  相似文献   
22.
The objective of this study was to investigate the ameliorative property and potential mechanism of resveratrol (RVT) in a dose of 10 mg/kg for 15 consecutive days against liver injury in streptozotocin‐induced diabetic rats. Diabetic rats significantly (P < 0.05) exhibited liver injury manifested by increased aspartylaminotransferase, alanine aminotransferase, and bilirubin; disturbed liver weight to body weight; and confirmed by hematoxylin and eosin staining. Liver from diabetic rats exhibited significant increase in malondialdehyde level and significant decrease in reduced glutathione, glutathione‐S‐transferase, quinone reductase, catalase, and superoxide dismutase. Diabetic rats showed significant disturbance in serum lipid profile. Treatment with RVT significantly (P < 0.05) abrogated diabetes‐induced perturbation in these parameters and liver histology. These data suggest that RVT treatment is associated with promising hepatoprotective effect against diabetes‐induced liver damage via reduction of serum glucose level and oxidative damage and improving serum lipid profile. © 2012 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:384–392, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21432  相似文献   
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Human cancers have multiple alterations in cell signaling pathways that promote resistance to cytotoxic therapy such as X rays. Parthenolide is a sesquiterpene lactone that has been shown to inhibit several pro-survival cell signaling pathways, induce apoptosis, and enhance chemotherapy-induced cell killing. We investigated whether parthenolide would enhance X-ray-induced cell killing in radiation resistant, NF-kappaB-activated CGL1 cells. Treatment with 5 microM parthenolide for 48 to 72 h inhibited constitutive NF-kappaB binding and cell growth, reduced plating efficiency, and induced apoptosis through stabilization of p53 (TP53), induction of the pro-apoptosis protein BAX, and phosphorylation of BID. Parthenolide also enhanced radiation-induced cell killing, increasing the X-ray sensitivity of CGL1 cells by a dose modification factor of 1.6. Flow cytometry revealed that parthenolide reduced the percentage of X-ray-resistant S-phase cells due to induction of p21 waf1/cip1 (CDKN1A) and the onset of G1/S and G2/M blocks, but depletion of radioresistant S-phase cells does not explain the observed X-ray sensitization. Further studies demonstrated that the enhancement of X-ray-induced cell killing by parthenolide is due to inhibition of split-dose repair.  相似文献   
25.
Obesity is a major global public health concern. Immune responses implicated in obesity also control certain infections. We investigated the effects of high‐fat diet‐induced obesity (DIO) on infection with the Lyme disease bacterium Borrelia burgdorferi in mice. DIO was associated with systemic suppression of neutrophil‐ and macrophage‐based innate immune responses. These included bacterial uptake and cytokine production, and systemic, progressive impairment of bacterial clearance, and increased carditis severity. B. burgdorferi‐infected mice fed normal diet also gained weight at the same rate as uninfected mice fed high‐fat diet, toll‐like receptor 4 deficiency rescued bacterial clearance defects, which greater in female than male mice, and killing of an unrelated bacterium (Escherichia coli) by bone marrow‐derived macrophages from obese, B. burgdorferi‐infected mice was also affected. Importantly, innate immune suppression increased with infection duration and depended on cooperative and synergistic interactions between DIO and B. burgdorferi infection. Thus, obesity and B. burgdorferi infection cooperatively and progressively suppressed innate immunity in mice.  相似文献   
26.
Studies have shown that excessive alcohol consumption impacts the intestinal microbiota composition, causing disruption of homeostasis (dysbiosis). However, this observed change is not indicative of the dysbiotic intestinal microbiota function that could result in the production of injurious and toxic products. Thus, knowledge of the effects of alcohol on the intestinal microbiota function and their metabolites is warranted, in order to better understand the role of the intestinal microbiota in alcohol associated organ failure. Here, we report the results of a differential metabolomic analysis comparing volatile organic compounds (VOC) detected in the stool of alcoholics and non-alcoholic healthy controls. We performed the analysis with fecal samples collected after passage as well as with samples collected directly from the sigmoid lumen. Regardless of the approach to fecal collection, we found a stool VOC metabolomic signature in alcoholics that is different from healthy controls. The most notable metabolite alterations in the alcoholic samples include: (1) an elevation in the oxidative stress biomarker tetradecane; (2) a decrease in five fatty alcohols with anti-oxidant property; (3) a decrease in the short chain fatty acids propionate and isobutyrate, important in maintaining intestinal epithelial cell health and barrier integrity; (4) a decrease in alcohol consumption natural suppressant caryophyllene; (5) a decrease in natural product and hepatic steatosis attenuator camphene; and (6) decreased dimethyl disulfide and dimethyl trisulfide, microbial products of decomposition. Our results showed that intestinal microbiota function is altered in alcoholics which might promote alcohol associated pathologies.  相似文献   
27.
Our laboratory has previously developed scaffoldless engineered bone constructs (EBC). Bone marrow stromal cells (BMSC) were harvested from rat femur and cultured in medium that induced osteogenic differentiation. After reaching confluence, the monolayer of cells contracted around two constraint points forming a cylinder. EBCs were placed in small diameter (0.5905 × 0.0625 in.) or large diameter (0.5905 × 0.125 in.) silicone tubing and implanted intramuscularly in the hind limb of a rat. Bone mineral content (BMC) of the EBC was analyzed before implantation and at 1 and 2 mo following implantation and compared to that of native femur bone at different stages of development. Negligible BMC was observed in E-20 femur or EBCs prior to implantation. One-month implantation in both small and large tubing increased BMC in the EBC. BMC of EBC from large tubing was greater than in 14 d rat neonatal femurs, but was 2% and 3% of BMC content in adult bone after 1 and 2 mo of implantation, respectively. Alizarine Red and osteopontin staining of the EBCs before and after implantation confirmed increased bone mineralization in the implanted EBCs. Implanted EBCs also had extensive vascularization. Our data suggest that BMSC can be successfully used for the generation of scaffoldless EBC, and this model can be potentially used for the generation of autologous bone transplants in humans.  相似文献   
28.

Objective

Mortality in heart failure (AHF) remains high, especially during the first days of hospitalization. New prognostic biomarkers may help to optimize treatment. The aim of the study was to determine metabolites that have a high prognostic value.

Methods

We conducted a prospective study on a training cohort of AHF patients (n = 126) admitted in the cardiac intensive care unit and assessed survival at 30 days. Venous plasmas collected at admission were used for 1H NMRbased metabonomics analysis. Differences between plasma metabolite profiles allow determination of discriminating metabolites. A cohort of AHF patients was subsequently constituted (n = 74) to validate the findings.

Results

Lactate and cholesterol were the major discriminating metabolites predicting 30-day mortality. Mortality was increased in patients with high lactate and low total cholesterol concentrations at admission. Accuracies of lactate, cholesterol concentration and lactate to cholesterol (Lact/Chol) ratio to predict 30-day mortality were evaluated using ROC analysis. The Lact/Chol ratio provided the best accuracy with an AUC of 0.82 (P < 0.0001). The acute physiology and chronic health evaluation (APACHE) II scoring system provided an AUC of 0.76 for predicting 30-day mortality. APACHE II score, Cardiogenic shock (CS) state and Lact/Chol ratio ≥ 0.4 (cutoff value with 82% sensitivity and 64% specificity) were significant independent predictors of 30-day mortality with hazard ratios (HR) of 1.11, 4.77 and 3.59, respectively. In CS patients, the HR of 30-day mortality risk for plasma Lact/Chol ratio ≥ 0.4 was 3.26 compared to a Lact/Chol ratio of < 0.4 (P  =  0.018). The predictive power of the Lact/Chol ratio for 30-day mortality outcome was confirmed with the independent validation cohort.

Conclusion

This study identifies the plasma Lact/Chol ratio as a useful objective and simple parameter to evaluate short term prognostic and could be integrated into quantitative guidance for decision making in heart failure care.  相似文献   
29.
The aim of this study was to investigate macrophage reverse cholesterol transport (RCT) in hamster, a CETP-expressing species, fed omega 3 fatty acids (ω3PUFA) supplemented high fat diet (HFD). Three groups of hamsters (n = 6/group) were studied for 20 weeks: 1) control diet: Control, 2) HFD group: HF and 3) HFD group supplemented with ω3PUFA (EPA and DHA): HFω3. In vivo macrophage-to-feces RCT was assessed after an intraperitoneal injection of 3H-cholesterol-labelled hamster primary macrophages.Compared to Control, HF presented significant (p<0.05) increase in body weight, plasma TG (p<0.01) and cholesterol (p<0.001) with an increase in VLDL TG and in VLDL and LDL cholesterol (p<0.001).Compared to HF, HFω3 presented significant decrease in body weight. HFω3 showed less plasma TG (p<0.001) and cholesterol (p<0.001) related to a decrease in VLDL TG and HDL cholesterol respectively and higher LCAT activity (p<0.05) compared to HF. HFω3 showed a higher fecal bile acid excretion (p<0.05) compared to Control and HF groups and higher fecal cholesterol excretion (p<0.05) compared to HF. This increase was related to higher gene expression of ABCG5, ABCA1 and SR-B1 in HFω3 compared to Control and HF groups (<0.05) and in ABCG1 and CYP7A1 compared to HF group (p<0.05). A higher plasma efflux capacity was also measured in HFω3 using 3H- cholesterol labeled Fu5AH cells.In conclusion, EPA and DHA supplementation improved macrophage to feces reverse cholesterol transport in hamster fed HFD. This change was related to the higher cholesterol and fecal bile acids excretion and to the activation of major genes involved in RCT.  相似文献   
30.

Background

Bangladesh is one of the most vulnerable countries to climate change. People are getting educated at different levels on how to deal with potential impacts. One such educational mode was the preparation of a school manual, for high school students on climate change and health protection endorsed by the National Curriculum and Textbook Board, which is based on a 2008 World Health Organization manual. The objective of this study was to test the effectiveness of the manual in increasing the knowledge level of the school children about climate change and health adaptation.

Methods

This cluster randomized intervention trial involved 60 schools throughout Bangladesh, with 3293 secondary school students participating. School upazilas (sub-districts) were randomised into intervention and control groups, and two schools from each upazila were randomly selected. All year seven students from both groups of schools sat for a pre-test of 30 short questions of binary response. A total of 1515 students from 30 intervention schools received the intervention through classroom training based on the school manual and 1778 students of the 30 control schools did not get the manual but a leaflet on climate change and health issues. Six months later, a post-intervention test of the same questionnaire used in the pre-test was performed at both intervention and control schools. The pre and post test scores were analysed along with the demographic data by using random effects model.

Results

None of the various school level and student level variables were significantly different between the control and intervention group. However, the intervention group had a 17.42% (95% CI: 14.45 to 20.38, P = <0.001) higher score in the post-test after adjusting for pre-test score and other covariates in a multi-level linear regression model.

Conclusions

These results suggest that school-based intervention for climate change and health adaptation is effective for increasing the knowledge level of school children on this topic.  相似文献   
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