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41.
Tannins (hydrolyzable and condensed) are water-soluble polyphenolic compounds that exert antinutritional effects on ruminants by forming complexes with dietary proteins. They limit nitrogen supply to animals, besides inhibiting the growth and activity of ruminal microflora. However, some gastrointestinal microbes are able to break tannin–protein complexes while preferentially degrading hydrolyzable tannins (HTs). Streptococcus gallolyticus, Lonepinella koalarum and Selenomonas ruminantium are the dominant bacterial species that have the ability to degrade HTs. These tanninolytic microorganisms possess tannin-degrading ability and have developed certain mechanisms to tolerate tannins in feeds. Hence, selection of efficient tanninolytic microbes and transinoculation among animals for long-term benefits become areas of intensive interest. Here, we review the effects of tannins on ruminants, the existence and significance of tannin-degrading microorganisms in diverse groups of animals and the mechanisms that tannin-degrading microorganisms have developed to counter the toxic effects of tannin.  相似文献   
42.
Camptothecin (CPT), a broad spectrum antineoplastic agent, is known to induce oxidative stress and mitochondria are among the main sources of intracellular reactive oxygen species (ROS). We investigated the merit of vitamins E and C supplementation on CPT-induced mitochondrial alterations in vitro. Following treatment of isolated liver mitochondria with CPT, we assessed the mitochondrial membrane permeability transition (MPT), concentration of malondialdehyde, antioxidants and activities of the enzymes of the respiratory chain and Krebs cycle. Our results provide evidence that CPT caused mitochondrial swelling, increased lipid peroxidation and transition of mitochondrial permeability. The CPT lowered the levels of reduced mitochondrial thiols suggesting that thiol oxidation is the mechanism underlying CPT-induced MPT. Identical experiments were also performed after preincubating the mitochondria with vitamins E and C. It was found that vitamins E and C pretreatment inhibited the deleterious effects of CPT and loss of enzyme activity was restored by antioxidant supplementation. Our results suggest that the toxicity of CPT was mediated by an increase in ROS production by mitochondria. However, the addition of vitamins E or C ameliorated the oxidative stress. We propose that an attempt to counteract the deleterious consequences of chemotherapy with nutritional therapies may be a rational approach in superior patient care especially in a disease like cancer.  相似文献   
43.
The objective of this study was to evaluate the impact of urbanization and seasonal changes on the prevalence of antibiotic-resistant bacteria in different aqueous environments. To this end, bacteria were isolated from three different water sources: the River Hooghly in Kolkata, River Kangsabati and groundwater from Kharagpur, West Bengal over three seasons: post-monsoon, winter and summer in 2012–2013. A total of 163 Gram-negative bacteria were isolated from the River Hooghly (n?=?138), River Kangsabati (n?=?13) and groundwater (n?=?12). Antibiotic susceptibility testing was done using 12 antibiotic discs. The percentages of multiple antibiotic-resistant (MAR) bacteria at the three sampling locations were found to be 71.01 % (98/138) for River Hooghly, 15.38 % (2/13) for River Kangsabati and 8.33 % (1/12) for groundwater. Prevalence of MAR bacteria with respect to the three seasons were the following: 73.58 % in post-monsoon, 59.26 % in winter and 53.57 % in summer. Antibiotic resistance index (ARI) was calculated for each location and each season. In general, ARI values for all the River Hooghly samples were >0.2 while those for the River Kangsabati and groundwater in Kharagpur were always <0.2 indicating greater exposure to antibiotics and subsequent resistance in bacteria from the River Hooghly compared to the other two locations. In addition, percentage of MAR and ARI values followed the trend: post-monsoon?>?winter?>?summer. This may be due to the additional terrestrial resistants that get swept along with surface runoff during the monsoons.  相似文献   
44.
Environmental Science and Pollution Research - Coronaviruses are terrifically precise and adapted towards specialized respiratory epithelial cells, observed in organ culture and human volunteers...  相似文献   
45.
Environmental Science and Pollution Research - Prophylactic usage and high persistent nature of several antibiotics have put selective pressure on the native microbial population that led to the...  相似文献   
46.
47.
Objective: The State of Connecticut has a partial motorcycle helmet law, which has been linked to one of the lowest helmet compliance rates in the Northeast. We examine the clinical and financial impact of low motorcycle helmet use in the State of Connecticut.

Methods: A retrospective cohort study comparing the outcomes between helmeted and nonhelmeted motorcycle crash victims over a 12.5-year period, from July 2, 2002, to December 31, 2013. All patients who were admitted to the hospital after a motorcycle crash were included in the study. Patients were stratified into helmeted and nonhelmeted cohorts. Group differences were compared using t-test or Wilcoxon rank test for continuous variables and chi-square test for dichotomous outcomes. Regression models were created to evaluate predictors of helmet use, alcohol and drugs as confounding variables, and factors that influenced hospital costs.

Results: The registry included 986 eligible patients. Of this group, 335 (34%) were helmeted and 651 (66%) were nonhelmeted. Overall, nonhelmeted patients had a worse clinical presentation, with lower Glasgow Coma Scale (GCS; P <.01), higher Injury Severity Score (ISS; P <.01), higher incidence of loss of consciousness (LOC; P <.01), longer intensive care unit (ICU; P <.01) admissions, and higher incidence of head (P <.01) or face injuries (P <.01). Nonhelmeted patients were also twice as more likely to die from their injuries (P =.04, odds ratio [OR] = 1.89, 95% confidence interval [CI], 1.02–3.45). Financially, nonhelmeted patients incurred mean hospital costs of $18,458, whereas helmeted patients incurred $14,970 (P =.18). ISS, GCS, and ICU length of stay were significantly correlated with increased hospital costs (P <.01). Not using a helmet was a significant predictor of mortality (P =.04) after adjusting for alcohol/drug use and age.

Conclusions: Helmet use is associated with lower injury severity and increased survival after a motorcycle crash. These outcomes remained consistent even after controlling for age and alcohol and drug use. The medical and financial impact of Connecticut's partial helmet law should be carefully evaluated to petition for increased education and enforcement of helmet use.  相似文献   

48.
The genotoxic effects of oxidative metabolites of trichloroethylene (TCE), namely chloral hydrate, trichloroacetic acid (TCA), dichloroacetic acid (DCA), and trichloroethanol (TCEOH) were examined in human peripheral blood lymphocytes. In this context, lymphocytes were exposed in vitro to 25, 50, and 100 μg/ml concentrations of these metabolites separately for a period of 48 h and examined for micronucleus (MN) induction through flow cytometer. At 50 μg/ml TCE metabolites, TCA (6.33?±?0.56 %), DCA (5.06?±?0.55), and TCEOH (4.70?±?1.73) induced highly significant (p?<?0.001) frequency of MN in comparison to control (1.03?±?0.40) suggestive of their genotoxic potential. However, exposure of 100 μg/ml of all the metabolites consistently declined the frequencies of MN which in some cases was equable to that of observed at 25 μg/ml. Further, cytotoxicity and cell cycle disturbances were also measured to find out the association of these endpoints with the MN induction. DNA content analysis revealed 3–4-fold elevation of S-phase at all the concentrations tested. Particularly, at 100 μg/ml, treatment elevation of S-phase was significantly (p?<?0.0001) higher as compared to the control. Present findings together with earlier reports indicate that TCE induces genotoxicity through its metabolites. Interaction of these metabolites with DNA, as evident by elevated S-phase, seems to be the major cause of MN induction. However, involvement of spindle disruption cannot be ruled out. This comparative study also suggests that after TCE exposure, the metabolic efficiency of human to generate oxidative metabolites determines the extent of genotoxicity.  相似文献   
49.
The present study describes the treatment of sugar industry waste water and its use as a potential low cost substrate for production of bioplastic by Bacillus subtilis NG05. The B. subtilis NG05 grow at the rate of 0.14 g h?1 L?1 of production media used and accumulate the 50.1 % of poly β-hydroxybutyrate (PHB). The phase contrast microscopy revealed the presence of PHB granules in B. subtilis NG05 which was further confirmed by Fourier transform infrared spectroscopy and 1H-nuclear magnetic resonance. The polymer was further analysed by differential scanning calorimetry. PHB production yield was achieved up to 4.991 g L?1 with Sugar industry waste water as sole nutrient source. Thus the process provided dual benefits of conversion of a waste material into value added product, PHB and waste management.  相似文献   
50.
Worldwide, about 150 000 infants are born with spina bifida yearly, making this condition one of the most common fetal central nervous system anomalies compatible with life. Over the last decade, major changes have been introduced in the prenatal diagnosis and management of spina bifida. In this review, we provide a brief summary of the current management of fetal spina bifida and present essential information that should be provided to expecting parents when their fetus has been diagnosed with spina bifida. This information is focused around common parental questions, as encountered in our typical clinical practice, to facilitate knowledge translation.  相似文献   
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