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Human carbonyl reductase (CBR) activity accounts for a significant fraction of the metabolism of endogenous and xenobiotic carbonyl compounds. It is possible that genetic polymorphisms in CBR1 and CBR3 are key for the wide interindividual variability in the disposition of CBR drug substrates. We pinpointed a single nucleotide polymorphism in CBR3 (CBR3 V244M) that encodes for a V244 to M244 change. Blacks showed a higher frequency of the M244 allele (q = 0.51, n = 49) than did whites (q = 0.31, n = 70; p = 0.003). In addition, DNA variation panels from 10 ethnic groups presented a wide range of CBR3 V244M genotype distributions. Kinetic experiments with the recombinant CBR3 protein variants and menadione revealed that CBR3 M244 has significantly higher V(max) than does CBR3 V244 (V(max) CBR3 M244 = 40.6 +/- 1.3 micromol/min x mg versus V(max) CBR3 V244 = 19.6 +/- 2.0 micromol/min x mg, p = 0.002). In contrast, both isoforms presented similar K(m) values (K(m) CBR3 M244 = 22.9 +/- 2.9 microM versus K(m) CBR3 V244 = 24.6 +/- 3.2 microM, p = 0.43). Assays with NADP(H) demonstrated a higher V(maxNADP(H)) (1.6-fold) and increased catalytic efficiency (V(maxNADP(H))/K(mNADP(H))) for CBR3 M244 compared with CBR3 V244 (p = 0.013). Comparative three-dimensional analyses based on the structure of the homologous porcine carbonyl reductase suggested that the V244M substitution is positioned in a region critical for interactions with the NADP(H) cofactor. These studies demonstrate that the common CBR3 V244M polymorphism encodes for CBR3 isoforms with distinctive enzymatic properties.  相似文献   
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We report the positive identification of several members of the guerrillas led by Ernesto “Che” Guevara on the 1960 s in Bolivia by means of DNA fingerprinting. Successful DNA typing of both short tandem repeat loci and the hypervariable region of the human mitochondrial DNA was achieved after extracting total DNA from bones obtained from two burial sites. Given the size of the Cuban database for the STR allele frequencies, a conservative approach was followed to estimate the statistical significance of the genetic evidence. The estimated probabilities of paternity for the two cases in which the paternity logic was applied were higher than 99%. One case was analyzed using mitochondrial DNA and could not be excluded from the identity proposed by the forensic anthropology team. A fourth case was identified by exclusion, on the basis of the positive identification of the other remains, the historical and other anthropological evidence. Received: 19 January 1999 / Received in revised form: 15 April 1999  相似文献   
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Study Objective

To describe the potential role of intraoperative ultrasound (IOUS) in the detection and localization of recurrent disease in gynecologic cancer patients during minimally invasive surgery (MIS).

Design

A prospective cohort study (Canadian Task Force classification II-1).

Setting

A university hospital.

Patients

Fifty-one gynecologic cancer patients with isolated recurrent disease.

Interventions

IOUS during secondary cytoreductive surgery (SCS) by MIS.

Measurements and Main Results

From November 2015 to February 2017 51 gynecologic cancer patients with isolated recurrent disease and candidates for SCS were treated by MIS. Recurrent tumor was preoperatively assessed at clinical examination, transvaginal and transabdominal sonography, and radiologic evaluation in all women. Twelve of 51 women (23.5%) needed IOUS. Type of disease was ovarian in 5 women (42%), endometrial in 4 (33%), cervical in 1 (8%), vaginal cancer in 1 (8%), and uterine sarcoma in 1 (8%). Recurrence was localized deep in the pelvis in 7 cases (58%), lymph nodes in 3 (25%), and extraperitoneal in 2 cases (17%). Recurrence was dimmed in the surgical field, due to either presence of adherences, deep anatomic position, small size, and/or lack of tactile feeling. IOUS was able to identify the lesions in all women, allowing MIS (83% laparoscopy and 17% robotic) complete cytoreduction, with no conversion to laparotomy. Median operative time was 150 minutes (range, 77–280). No intraoperative/postoperative complications occurred. Histologic examination confirmed the presence of recurrence in 11 of 12 cases (92%), whereas the remaining case showed inflammatory tissue. With a median follow-up time of 15 months (range, 6–19), all patients except 2 were still alive.

Conclusions

About 1 of 4 patients (25%) with single gynecologic cancer recurrence needs IOUS to benefit from MIS for complete secondary cytoreduction.  相似文献   
88.
Journal of Assisted Reproduction and Genetics - To study whether a new combination of different warming kits is clinically effective for vitrified human blastocysts. This is a longitudinal cohort...  相似文献   
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BackgroundMany esophageal pathologies are clinically treated by resection and reconstruction of the esophagus. Surgical esophagectomy remains a morbid procedure and despite minimally invasive advances, has changed little in decades. Novel approaches to esophageal segmental resection and reconstruction are an unmet need.MethodsCircumferential thoracic esophageal transection was performed in both male and female pigs and the defects reconstructed using 5 or 10 cm polyurethane (PU) tubular grafts and stented. A subset were treated with stent only. Animals were survived to 14, 30, 60, and 399 days. Tissues were evaluated histologically, and via non-invasive serial endoscopy and contrast swallowing studies in long-term animals.ResultsLuminal patency was achieved in all animals with no clinical evidence of leak. In short-term animals, there was healing noted in all cases with a variably sized region of ulceration remaining at the most central part of the repaired tube (between the proximal and distal anastomosis). In four long-term animals following stent removal, two resumed normal diet and thrived, while two animals were euthanized prior to the proposed endpoint because of stricture formation and inability to tolerate a normal diet. Re-epithelialization was observed in all groups, and more complete over time.ConclusionsThe PU scaffold provides a matrix across which formation of new tissue can occur. The mechanisms through which this happens remain unclear, but likely a combination of fibrosis and tissue contraction, in conjunction with new tissue formation.  相似文献   
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