741 research outputs found
Amelioration of bleomycin-induced lung fibrosis in hamsters by dietary supplementation with taurine and niacin: biochemical mechanisms.
Interstitial pulmonary fibrosis induced by intratracheal instillation of bleomycin (BL) involves an excess production of reactive oxygen species, unavailability of adequate levels of NAD and ATP to repair the injured pulmonary epithelium, and an overexuberant lung collagen reactivity followed by deposition of highly cross-linked mature collagen fibrils resistant to enzymatic degradation. In the present study, we have demonstrated that dietary supplementation with taurine and niacin offered almost complete protection against the lung fibrosis in a multidose BL hamster model. The mechanisms for the protective effect of taurine and niacin are multifaceted. These include the ability of taurine to scavenge HOCl and stabilize the biomembrane; niacin's ability to replenish the BL-induced depletion of NAD and ATP; and the combined effect of taurine and niacin to suppress all aspects of BL-induced increases in the lung collagen reactivity, a hallmark of interstitial pulmonary fibrosis. It was concluded from the data presented at this Conference that the combined treatment with taurine and niacin, which offers a multipronged approach, will have great therapeutic potential in the intervention of the development of chemically induced interstitial lung fibrosis in animals and humans
Control of intestinal stem cell function and proliferation by mitochondrial pyruvate metabolism.
Most differentiated cells convert glucose to pyruvate in the cytosol through glycolysis, followed by pyruvate oxidation in the mitochondria. These processes are linked by the mitochondrial pyruvate carrier (MPC), which is required for efficient mitochondrial pyruvate uptake. In contrast, proliferative cells, including many cancer and stem cells, perform glycolysis robustly but limit fractional mitochondrial pyruvate oxidation. We sought to understand the role this transition from glycolysis to pyruvate oxidation plays in stem cell maintenance and differentiation. Loss of the MPC in Lgr5-EGFP-positive stem cells, or treatment of intestinal organoids with an MPC inhibitor, increases proliferation and expands the stem cell compartment. Similarly, genetic deletion of the MPC in Drosophila intestinal stem cells also increases proliferation, whereas MPC overexpression suppresses stem cell proliferation. These data demonstrate that limiting mitochondrial pyruvate metabolism is necessary and sufficient to maintain the proliferation of intestinal stem cells
Brain MRI and biological diagnosis in five Tunisians MLD patients
Metachromatic leukodystrophy (MLD) is a recessive autosomal disease which is characterized by an accumulation of sulfatides in the central and peripheral nervous system. It is due to the enzyme deficiency of the sulfatide sulfatase i.e. arylsulfatase A (ASA). we studied 5/200 cases of MLD and clearly distinguished three clinical forms. One of them presented the juvenile form; two presented the late infantile form; and two other presented the adult form. The Magnetic Resonance Imaging (MRI) of these patients showed a diffuse, bilateral and symmetrical demyelination. The biochemical diagnosis of MLD patients evidencing the low activity of ASA and sulfatide accumulation
Haloalkaliphilic spore-forming sulfidogens from soda lake sediments and description of Desulfitispora alkaliphila gen. nov., sp. nov.
An anaerobic enrichment with pyruvate as electron donor and thiosulfate at pH 10 and 0.6 M Na+ inoculated with pasteurized soda lake sediments resulted in a sulfidogenic coculture of two morphotypes of obligately anaerobic haloalkaliphilic endospore-forming clostridia, which were further isolated in pure culture. Strain AHT16 was a thin long rod able to ferment sugars and pyruvate and to respire H2, formate and pyruvate using thiosulfate and fumarate as electron acceptors and growing optimally at pH 9.5. Thiosulfate was reduced incompletely to sulfide and sulfite. The strain was closely related (99% sequence similarity) to a peptolytic alkaliphilic clostridium Natronincola peptidovorans. Strain AHT17 was a short rod with a restricted respiratory metabolism, growing with pyruvate and lactate as electron donor and sulfite, thiosulfate and elemental sulfur as electron acceptors with a pH optimum 9.5. Thiosulfate was reduced completely via sulfite to sulfide. The ability of AHT17 to use sulfite explained the stability of the original coculture of the two clostridia—one member forming sulfite from thiosulfate and another consuming it. Strain AHT17 formed an independent deep phylogenetic lineage within the Clostridiales and is proposed as a new genus and species Desulfitisporum alkaliphilum gen. nov., sp. nov. (=DSM 22410T = UNIQEM U794T)
Clinical quality measures for intraoperative and perioperative management in carpal tunnel surgery
Aerosolized Delivery of Antifungal Agents
Pulmonary infections caused by Aspergillus species are associated with significant morbidity and mortality in immunocompromised patients. Although the treatment of pulmonary fungal infections requires the use of systemic agents, aerosolized delivery is an attractive option in prevention because the drug can concentrate locally at the site of infection with minimal systemic exposure. Current clinical evidence for the use of aerosolized delivery in preventing fungal infections is limited to amphotericin B products, although itraconazole, voriconazole, and caspofungin are under investigation. Based on conflicting results from clinical trials that evaluated various amphotericin B formulations, the routine use of aerosolized delivery cannot be recommended. Further research with well-designed clinical trials is necessary to elucidate the therapeutic role and risks associated with aerosolized delivery of antifungal agents. This article provides an overview of aerosolized delivery systems, the intrapulmonary pharmacokinetic properties of aerosolized antifungal agents, and key findings from clinical studies
Modulation of Brain β-Endorphin Concentration by the Specific Part of the Y Chromosome in Mice
International audienceBackground: Several studies in animal models suggest a possible effect of the specific part of the Y-chromosome (Y NPAR) on brain opioid, and more specifically on brain b-endorphin (BE). In humans, male prevalence is found in autistic disorder in which observation of abnormal peripheral or central BE levels are also reported. This suggests gender differences in BE associated with genetic factors and more precisely with Y NPAR. Methodology/Principal Findings: Brain BE levels and plasma testosterone concentrations were measured in two highly inbred strains of mice, NZB/BlNJ (N) and CBA/HGnc (H), and their consomic strains for the Y NPAR. An indirect effect of the Y NPAR on brain BE level via plasma testosterone was also tested by studying the correlation between brain BE concentration and plasma testosterone concentration in eleven highly inbred strains. There was a significant and major effect (P,0.0001) of the Y NPAR in interaction with the genetic background on brain BE levels. Effect size calculated using Cohen's procedure was large (56% of the total variance). The variations of BE levels were not correlated with plasma testosterone which was also dependent of the Y NPAR. Conclusions/Significance: The contribution of Y NPAR on brain BE concentration in interaction with the genetic background is the first demonstration of Y-chromosome mediated control of brain opioid. Given that none of the genes encompassed by the Y NPAR encodes for BE or its precursor, our results suggest a contribution of the sex-determining region (Sry, carried by Y NPAR) to brain BE concentration. Indeed, the transcription of the Melanocortin 2 receptor gene (Mc2R gene, identified as the proopiomelanocortin receptor gene) depends on the presence of Sry and BE is derived directly from proopiomelanocortin. The results shed light on the sex dependent differences in brain functioning and the role of Sry in the BE system might be related to the higher frequency of autistic disorder in males
Evaluation of effectiveness of class-based nutrition intervention on changes in soft drink and milk consumption among young adults
<p>Abstract</p> <p>Background</p> <p>During last few decades, soft drink consumption has steadily increased while milk intake has decreased. Excess consumption of soft drinks and low milk intake may pose risks of several diseases such as dental caries, obesity, and osteoporosis. Although beverage consumption habits form during young adulthood, which has a strong impact on beverage choices in later life, nutrition education programs on beverages are scarce in this population. The purpose of this investigation was 1) to assess soft drink and milk consumption and 2) to evaluate the effectiveness of 15-week class-based nutrition intervention in changing beverage choices among college students.</p> <p>Methods</p> <p>A total of 80 college students aged 18 to 24 years who were enrolled in basic nutrition class participated in the study. Three-day dietary records were collected, verified, and analyzed before and after the intervention. Class lectures focused on healthful dietary choices related to prevention of chronic diseases and were combined with interactive hands on activities and dietary feedback.</p> <p>Results</p> <p>Class-based nutrition intervention combining traditional lecture and interactive activities was successful in decreasing soft drink consumption. Total milk consumption, specifically fat free milk, increased in females and male students changed milk choice favoring skim milk over low fat milk. (1% and 2%).</p> <p>Conclusion</p> <p>Class-based nutrition education focusing on prevention of chronic diseases can be an effective strategy in improving both male and female college students' beverage choices. Using this type of intervention in a general nutrition course may be an effective approach to motivate changes in eating behaviors in a college setting.</p
Natural Terpenes Prevent Mitochondrial Dysfunction, Oxidative Stress and Release of Apoptotic Proteins during Nimesulide-Hepatotoxicity in Rats
Nimesulide, an anti-inflammatory and analgesic drug, is reported to cause severe hepatotoxicity. In this study, molecular mechanisms involved in deranged oxidant-antioxidant homeostasis and mitochondrial dysfunction during nimesulide-induced hepatotoxicity and its attenuation by plant derived terpenes, camphene and geraniol has been explored in male Sprague-Dawley rats. Hepatotoxicity due to nimesulide (80 mg/kg BW) was evident from elevated SGPT, SGOT, bilirubin and histo-pathological changes. Antioxidants and key redox enzymes (iNOS, mtNOS, Cu/Zn-SOD, Mn-SOD, GPx and GR) were altered significantly as assessed by their mRNA expression, Immunoblot analysis and enzyme activities. Redox imbalance along with oxidative stress was evident from decreased NAD(P)H and GSH (56% and 74% respectively; P<0.001), increased superoxide and secondary ROS/RNS generation along with oxidative damage to cellular macromolecules. Nimesulide reduced mitochondrial activity, depolarized mitochondria and caused membrane permeability transition (MPT) followed by release of apoptotic proteins (AIF; apoptosis inducing factor, EndoG; endonuclease G, and Cyto c; cytochrome c). It also significantly activated caspase-9 and caspase-3 and increased oxidative DNA damage (level of 8-Oxoguanine glycosylase; P<0.05). A combination of camphene and geraniol (CG; 1∶1), when pre-administered in rats (10 mg/kg BW), accorded protection against nimesulide hepatotoxicity in vivo, as evident from normalized serum biomarkers and histopathology. mRNA expression and activity of key antioxidant and redox enzymes along with oxidative stress were also normalized due to CG pre-treatment. Downstream effects like decreased mitochondrial swelling, inhibition in release of apoptotic proteins, prevention of mitochondrial depolarization along with reduction in oxidized NAD(P)H and increased mitochondrial electron flow further supported protective action of selected terpenes against nimesulide toxicity. Therefore CG, a combination of natural terpenes prevented nimesulide induced cellular damage and ensuing hepatotoxicity
Interaction of cimetidine with P450 in a mouse model of hepatocarcinogenesis initiation
Many drugs and xenobiotics are lipophilic and they should be transformed into more polar water soluble compounds to be excreted. Cimetidine inhibits cytochrome P450. The aim of this study was to investigate the preventive and/or reversal action of cimetidine on cytochrome P450 induction and other metabolic alterations provoked by the carcinogen p-dimethylaminoazobenzene. A group of male CF1 mice received a standard laboratory diet and another group was placed on dietary p-dimethylaminoazobenzene (0.5% w w−1). After 40 days of treatment, animals of both groups received p-dimethylaminoazobenzene and two weekly doses of cimetidine (120 mg kg−1, i.p.) during a following period of 35 days. Cimetidine prevented and reversed δ-aminolevulinate synthetase induction and cytochrome P450 enhancement provoked by p-dimethylaminoazobenzene. However, cimetidine did not restore haem oxygenase activity decreased by p-dimethylaminoazobenzene. Enhancement in glutathione S-transferase activity provoked by p-dimethylaminoazobenzene, persisted in those animals then treated with cimetidine. This drug did not modify either increased lipid peroxidation or diminution of the natural antioxidant defence system (inferred by catalase activity) induced by p-dimethylaminoazobenzene. In conclusion, although cimetidine treatment partially prevented and reversed cytochrome P450 induction, and alteration on haem metabolism provoked by p-dimethylaminoazobenzene AB, it did not reverse liver damage or lipid peroxidation. These results further support our hypothesis on the necessary existence of a multiple biochemical pathway disturbance for the onset of hepatocarcinogenesis initiation
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