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Yasser Samman Imran Masood Vijay Vardhan Killampalli Neil Howell E. Kaya Alpar Sunil K. Banerjee 《European Journal of Trauma》2005,31(2):133-137
Background and Purpose:
Management of rib fractures constitutes a major part of the trauma workload of any unit. Rib fractures result in disrupted chest wall mechanics and ventilatory insufficiency. The ability of a lung injury scoring system to predict the degree of respiratory dysfunction after rib fractures was evaluated. 相似文献3.
The authors report two rare cases of 'non-syndromic spontaneous keloids' occuring in siblings. This represents another unexplored area in the field of 'keloid challenge', warranting further research and development. 相似文献
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Effect of nitration on protein tyrosine phosphatase and protein phosphatase activity in neuronal cell membranes of newborn piglets 总被引:2,自引:0,他引:2
Protein tyrosine phosphatase predominantly determines the status of protein tyrosine kinase-dependent phosphorylation of specific proteins and controls the survival and death of neurons. Previous studies have shown that protein tyrosine phosphatase activity is decreased during hypoxia in cortical membranes of the newborn piglet. We have also shown that nitric oxide (NO) free radicals are generated during hypoxia, and may result in modification of protein tyrosine phosphatase via peroxynitrite-mediated modification. The present study tests the hypothesis that the hypoxia-induced decrease in protein tyrosine phosphatase activity is NO-mediated. To test this hypothesis, in vitro experiments were conducted by measuring protein tyrosine phosphatase activity in the presence of an NO donor, sodium nitroprusside (SNP), or peroxynitrite. Since 3-nitrotyrosine is produced as a consequence of peroxynitrite reactions, we have also examined the effect of 3-nitrotyrosine on protein phophatase activity. Cerebral cortical P(2) membranes were prepared from seven normoxic newborn piglets and each sample was divided into three aliquots: a control group, a SNP group (exposed to 200 microM SNP), and a peroxynitrite group (exposed to 100 microM peroxynitrite). Protein tyrosine phosphatase activity was determined spectrophotometrically in the presence or absence of 2 microM bpV(phen), a highly selective inhibitor of protein tyrosine phosphatase. The protein tyrosine phosphatase activity was 198+/-25 nmol/mg protein/h in the normoxic group, 177+/-30 nmol/mg protein/h in the SNP group (p=NS versus normoxic) and 77+/-20 nmol/mg protein/h in the peroxynitrite group (p<0.001 versus normoxic). The results show that peroxynitrite but not SNP exposure results in decreased protein tyrosine phosphatase activity in vitro. Furthermore 3-nitrotyrosine (100 microm), a product of peroxynitrite, decreased the enzyme activity from 926+/-102 to 200+/-77 (p<0.001). We conclude that protein tyrosine phosphatase regulation is mediated by peroxynitrite. We propose that hypoxia-induced NO production leading to peroxynitrite formation is a potential mechanism of protein tyrosine phosphatase inactivation in vivo. The NO-induced decrease in protein tyrosine phosphatase and protein phosphatase activity, leading to Bcl-2 protein phosphorylation and loss of its antiapoptotic activity may be a NO-mediated mechanism of programmed cell death in the hypoxic brain. 相似文献
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G Patil MI Khan DK Patel S Sultana R Prasad I Ahmad 《Environmental toxicology and pharmacology》2012,34(2):436-445
Dolomite is a natural mineral of great industrial importance and used worldwide, thus millions of workers are at risk of occupational exposure. Its toxicity is however, meagerly documented. In the present investigation, a dolomite powder obtained from its milling unit was analyzed by some standard methods namely, optical microscopy, transmission electron microscopy and dynamic light scattering. Results showed that dolomite powder contained particles of different shapes and size both microparticles (MPs) and nanoparticles (NPs), suggesting potential occupational exposure of these particles. An attempt was therefore, made to investigate dolomite toxicity in a particle size-dependent manner in human lung epithelial cells A(549). The comparative toxicity evaluation of MPs and NPs was carried out by assessing their effects on cell viability, membrane damage, glutathione, reactive oxygen species (ROS), lipid peroxidation (LPO), micronucleus (MN) and proinflammatory cytokines, namely tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). These markers of cytotoxicity, genotoxicity and inflammation were assayed in cells exposed to MPs and NPs in a dose-and time-dependent manner. Invariably, their toxic effects were dose-and time-dependent while NPs in general were significantly more toxic. Notably, NPs caused oxidative stress, genotoxicity and inflammatory responses, as seen by significant induction of ROS, LPO, MN, TNF-α, IL-1β and IL-6. Thus, the study tends to suggest that separate health safety standards would be required for micrometer and nanometer scale particles of dolomite. 相似文献
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At our institution, kidney biopsies are performed by an interventional nephrologist with standardized guidelines using real‐time ultrasound. We hypothesized that patient factors could predict post biopsy complications. We did a retrospective review of 100 patients who underwent renal biopsy. Prebiopsy data obtained included demographics, blood pressure, laboratory studies, and kidney size. Biopsy procedure information was also recorded. Complications and post biopsy imaging was noted. A minor complication was defined as one not requiring intervention while a major complication required interventions like readmission or blood transfusion. The average age was 47 years, 41 were men, 51 were black, 30 had diabetes, 42 were obese, and 81 had hypertension. Twenty‐six patients had a complication; 14 minor and 12 major including 1 nephrectomy. Factors predictive of a complication were thrombocytopenia (p = 0.002) and inpatient status (p = 0.04). Drop in hemoglobin at 6 hours was moderately sensitive and specific for a bleeding complication with an ROC of 0.723. Thrombocytopenia and inpatient status are risk factors for complications after renal biopsy. Serum creatinine, obesity, blood pressure, kidney size, needle size, and number of passes were not predictive of a major complication in our study. 相似文献
9.
Imran Amir Rajesh Sharma William A. Bauman Mark A. Korsten 《The journal of spinal cord medicine》2013,36(1):21-23
AbstractThe efficacies of four bowel care regimens (bisacodyl suppositories, glycerin suppositories, mineral oil enemas and docusate sodium mini-enemas) were compared in seven subjects with traumatic spinal cord injury. Efficacy was assessed in terms of colonic transit time, bowel evacuation time and subjective responses to a questionnaire. Both docusate sodium mini-enemas and mineral oil enemas decreased total and left-sided colonic transit time. However, docusate sodium mini-enemas were superior to mineral oil enemas in terms of the decrease in bowel evacuation time and symptom reduction. Results in this small group of subjects suggest that docusate sodium mini-enemas may have advantages in the management of bowel evacuation in individuals with spinal cord injury. (J Spinal Cord Med 1998;21 -24) 相似文献
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