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The grinding of a whole tooth specimen has been considered the conventional method to extract genomic deoxyribonucleic acid (DNA) in forensic science. However, we have tried the less destructive reverse root canal filing (RRCF) method without disturbing the morphology of the tooth to achieve competent amplifiable DNA. A total of 27 pairs of bilateral intact extracted teeth from the same subject were used in three different simulated environmental conditions for the respective RRCF and conventional methods: (a) soil burial for six months, (b) incineration at 200º C for four minutes, and (c) immersion in water for two months. Qualitative agarose gel electrophoresis assessment and downstream amplification were performed. The results showed significantly higher mean DNA concentration for the RRCF method in all three environmental conditions (p value = 0.008) in comparison to the conventional method. However, comparable qualitative results were found in both methods for the mean DNA concentration for incinerated (159.49 ng/ml), soil (119.52 ng/ml), and water (108.60 ng/ml) samples. It was concluded that the RRCF method is better quantitively (ng/ml) and comparable in terms of quality with respect to the conventional method, with the added advantage of preservation of the tooth morphology.  相似文献   
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Hereditary angioedema type III (HAEIII) is a rare inherited swelling disorder that is associated with point mutations in the gene encoding the plasma protease factor XII (FXII). Here, we demonstrate that HAEIII-associated mutant FXII, derived either from HAEIII patients or recombinantly produced, is defective in mucin-type Thr309-linked glycosylation. Loss of glycosylation led to increased contact-mediated autoactivation of zymogen FXII, resulting in excessive activation of the bradykinin-forming kallikrein-kinin pathway. In contrast, both FXII-driven coagulation and the ability of C1-esterase inhibitor to bind and inhibit activated FXII were not affected by the mutation. Intravital laser-scanning microscopy revealed that, compared with control animals, both F12–/– mice reconstituted with recombinant mutant forms of FXII and humanized HAEIII mouse models with inducible liver-specific expression of Thr309Lys-mutated FXII exhibited increased contact-driven microvascular leakage. An FXII-neutralizing antibody abolished bradykinin generation in HAEIII patient plasma and blunted edema in HAEIII mice. Together, the results of this study characterize the mechanism of HAEIII and establish FXII inhibition as a potential therapeutic strategy to interfere with excessive vascular leakage in HAEIII and potentially alleviate edema due to other causes.  相似文献   
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Background  Postoperative ileus is a common condition after abdominal surgery. Many prokinetic drugs have been evaluated including osmotic laxatives. The data on colon-stimulating laxatives are scarce. This prospective, randomized, double-blind trial investigates the effect of the colon-stimulating laxative bisacodyl on postoperative ileus in elective colorectal resections. Materials and methods  Between November 2004 and February 2007, 200 consecutive patients were randomly assigned to receive either bisacodyl or placebo. Primary endpoint was time to gastrointestinal recovery (mean time to first flatus passed, first defecation, and first solid food tolerated; GI-3). Secondary endpoints were incidence and duration of nasogastric tube reinsertion, incidence of vomiting, length of hospital stay, and visual analogue scores for pain, cramps, and nausea. Results  One hundred sixty-nine patients were analyzed, and 31 patients discontinued the study. Groups were comparable in baseline demographics. Time to GI-3 was significantly shorter in the bisacodyl group (3.0 versus 3.7 days, P = 0.007). Of the single parameters defining GI-3, there was a 1-day difference in time to defecation in favor to the bisacodyl group (3.0 versus 4.0 days, P = 0.001), whereas no significant difference in time to first flatus or tolerance of solid food was seen. No significant difference in the secondary endpoints was seen. Morbidity and mortality did not differ between groups. Conclusion  Bisacodyl accelerated gastrointestinal recovery and might be considered as part of multimodal recovery programs after colorectal surgery.  相似文献   
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