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71.
Genotype-phenotype correlation in women with an abnormal phenotype associated with a duplication of the long arm of the X chromosome remains unclear. We report on prenatal diagnosis and follow-up of a girl with an Xq duplication and dysmorphic features. The abnormal phenotype included growth retardation, hypotonia, and nystagmus. In order to improve the resolution of the cytogenetic analysis, we used both conventional and array-based comparative genomic hybridization to perform a global molecular cytogenetic analysis of the genome. These molecular cytogenetic analyses showed a direct duplication Xq21.1 --> q25 without other chromosomal abnormalities. This duplication was originating from the paternal X chromosome. Moreover, a skewed X-inactivation pattern was observed leading to a partial functional disomy of the chromosomal region Xq21.1q25. This report and review of the literature suggest that functional disomy for chromosome X could explain the abnormal phenotype. In prenatal diagnosis, this can have implication for patient management and genetic counseling.  相似文献   
72.
The OPA1 gene, encoding a dynamin-related GTPase that plays a role in mitochondrial biogenesis, is implicated in most cases of autosomal dominant optic atrophy (ADOA). Sixty-nine pathogenic OPA1 mutations have been reported so far. Most of these are truncating mutations located in the GTPase domain coding region (exons 8-16) and at the 3'-end (exons 27-28). We screened 44 patients with typical ADOA using PCR-sequencing. We also tested 20 sporadic cases of bilateral optic atrophy compatible with ADOA. Of the 18 OPA1 mutations found, 14 have never been previously reported. The novel mutations include one nonsense mutation, 3 missense mutations, 6 deletions, one insertion and 3 exon-skipping mutations. Two of these are de novo mutations, which were found in 2 patients with sporadic optic atrophy. The recurrent c.2708_2711delTTAG mutation was found in 2 patients with a severe congenital presentation of the disease. These results suggest that screening for OPA1 gene mutations may be useful for patients with optic atrophy who have no affected relatives, or when the presentation of the disease is atypical as in the case of early onset optic atrophy.  相似文献   
73.
Pulmonary hypertension (PH) produces strain followed by hypertrophy and later dilatation of the right ventricle (RV) and pulmonary artery. The signs and symptoms are nonspecific. There is a need for a noninvasive sensitive way to diagnose PH. The purpose of this study is to evaluate phase abnormalities in radionuclide MUGA studies of patients with referred diagnosis of PH. In a retrospective analysis of 44 patients who had a radionuclide multigated study (MUGA) and contrast ventriculography (CV), 19 had high mean pulmonary pressure (over 20 mmHg) and a high pulmonary vascular resistance index (over 2.0). In 15 patients, a delayed phase segment in the RV corresponding to the pulmonary infundibulum and pulmonary conus was noted The Pulmonary Tongue sign (PT), 12 had PH (True positive) and 3 did not (false positive) on CV. No PT was seen in the remaining 29 patients, only 7 of them had PH (False negative). The sensitivity, specificity and accuracy of the PT sign in detecting PH was 80%, 72% and 77% respectively. The number of patients was too small to calculate the correlation of the grade of PT with the severity of PH. We conclude that The Pulmonary Tongue sign on a MUGA study is clinically useful in detecting PH.This project is supported by research project MLNO13 and funded by research Council, Kuwait University  相似文献   
74.
The excretion, tissue distribution, and binding of [14C]-formaldehyde were studied at different time intervals in male rats following a single intraperitoneal injection of 72 mg CH2O (14.7 Ci)/ kg body weight. Within 30 min, 10% of the total dose was recovered in expired air as14CO2 and by the end of 72 hr, 41% of the administered dose was eliminated through expired air. The total elimination of14CH2O activity in urine and feces in 72 hr was 15%. Erythrocytes retained significant amounts of radioactivity, even at the end of 72 hr. Substantial levels of radioactivity were detected in most tissues one hr after administration, indicating a fast absorption and rapid distribution. Subcellular fractionation of the tissues showed that the highest levels of relative percent binding was in the microsomal fraction, whereas cytosol fractions contained lowest levels of bound radioactivity. DNA, RNA, protein and lipid fractions of liver and spleen tissues showed significantly elevated levels of14C-incorporation as compared to other tissues. Thein vivo incorporation of14C-activity showed an increased association of14CH2O with RNA in all the tissues. The maximum registration of radioactivity in RNA was at 48 hr after administration. Significantly higher amounts of14C-activity were registered in DNA of all tissues. The maximum registration of radiolabel in DNA of most tissues was at 12 hr after the14CH2O administration. The liver DNA showed maximal levels at 3 hr with a second peak at 48 hr.Substantial amounts of bound radioactivity in nucleic acids of all the tissues were observed even 72 hr after dosing. The relationship between macromolecular association and formaldehyde toxicity has been discussed.  相似文献   
75.
Summary A new synthetic tripeptide (p-F-Phe-m-bis-(2-chloroethyl)amino-Phe-Met ethoxy HCl), PTT.119, was demonstrated to have significant cancericidal activity against seven in vitro tumor cell lines of different origins and etiologies and against primary human AMML, ALL, and hairy cell leukemias. Viabilities of each murine tumor and rabbit, marmoset, and human leukemia and lymphoma line were significantly reduced by treatment with 1–50 g PTT.119 in media containing serum. Continuous 24-h exposure or pulse treatment as short as 15 and 30 min with the tripeptide resulted in irreversible damage to the tumor cells. Under identical treatment conditions, freshly isolated human leukemic cells, particularly ALL lymphoblasts, were even more susceptible to PTT.119 than any of the tested tumor cell models.Examination of the parameters of PTT.119 activity revealed that reductions of tumor cell survival were dependent on the concentration of the tripeptide. Prolongation of PTT.119 exposure from 15 min to 24 h increased the rates of tumor cell death but did not proportionally reduce the numbers of surviving cells. Assessment of tumor cell viabilities for 5 consecutive days following pulse exposure to PTT.119 demonstrated increasing reductions in tumor cell survival, which were greatest 5 days after treatment with the tripeptide.The cancericidal activity of PTT.119 was compared with its three parental components either as individual agents or as a mixture. Both the alkylator moiety, m-sarcolysin (m.L.SL) alone or together with p-fluoro-phenylalanine and l-methionine ethoxy HCl, and l-PAM (l-phenylalanine mustard), the p-isomer of m.L.SL, were 1.5- to 3-fold less cytotoxic to L1210 leukemia and MJY-alpha mammary tumor cells than PTT.119. Covalent linkage of the amino acid residues to m.L.SL yielded a molecule with greatly augmented cancericidal activity capable of acting against a broad spectrum of tumor cells.  相似文献   
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BackgroundOrgan transplantation is considered one of the greatest advances of modern science, and it has given many patients a renewed lease on life. The demand for organs far exceeds the supply. Health professionals are fundamental in the process of organ procurement.ObjectiveTo assess the attitude, willingness, and associated factors in organ donation among health professionals of Gondar, Ethiopia.MethodsOur cross-sectional study was conducted among 382 randomly selected health professionals in Gondar using a self-administered questionnaire. Multivariable logistic regression analysis was applied to analyze the data.ResultsAmong health professionals, 79.1% had favorable attitude toward organ donation and 74.6% were willing to donate their organs. After adjusting for covariates, the odds of having a favorable attitude about organ donation were 3.2 and 11.9 times higher in the professions of laboratory technologists and medical doctors, respectively. By keeping all other variables constant, attitude was found to be positively associated with awareness (adjusted odds ratio [aOR] 12.74, 95% confidence interval [CI] 3.71-43.8) and being a member of the Red Cross Association (aOR 5.24, 95% CI 1.46-18.96). Willingness was positively associated with awareness (aOR 6.25, 95% CI 2.0-19.53), a member of the Red Cross Association (aOR 5.09, 95% CI 1.5-17.22), a laboratory technologist (aOR 3.57, 95% CI 1.37-9.29), and a medical doctor (aOR 6.52, 95 % CI 1.93-22.01).ConclusionsThe main findings indicated that the majority of health professionals in Gondar had a favorable attitude toward organ donation and were willing to donate their organs in times of need.  相似文献   
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BackgroundThere has been increasing uptake of minimally invasive pancreatoduodenectomy during the past decade, but it remains a highly specialized procedure as benefits over open pancreatoduodenectomy remain contentious. This study aimed to evaluate current evidence on minimally invasive pancreatoduodenectomy versus open pancreatoduodenectomy in terms of impact of center volume on outcomes.MethodsA systematic review of articles on comparative cohort and registry studies on minimally invasive pancreatoduodenectomy versus open pancreatoduodenectomy published until 31st December 2019 were identified, and meta-analyses were performed. Primary endpoints were International Study Group on Pancreatic Fistula grade B/C postoperative pancreatic fistula and 30-day mortality.ResultsAfter screening 7,390 studies, 43 comparative cohort studies (8,755 patients) with moderate methodological quality and 3 original registry studies (43,735 patients) were included. For the cohort studies, the median annual hospital minimally invasive pancreatoduodenectomy volume was 10. No significant differences were found in grade B/C postoperative pancreatic fistula (odds ratio: 0.98, 95% confidence interval: 0.78–1.23) or 30-day mortality (odds ratio: 1.14, 95% confidence interval: 0.65–2.01) between minimally invasive pancreatoduodenectomy when compared with open. No publication biases were present and meta-regression identified no confounding for grade B/C postoperative pancreatic fistula, center volume or 30-day mortality. Minimally invasive pancreatoduodenectomy was only strongly associated with significantly lower rates of postoperative pulmonary complications and surgical site infection, shorter length of stay, and significantly higher rates of R0 margin resections.ConclusionMinimally invasive pancreatoduodenectomy remains noninferior to open pancreatoduodenectomy for grade B/C postoperative pancreatic fistula but is strongly associated with significantly lower rates of postoperative pulmonary complications and surgical site infection. Minimally invasive pancreatoduodenectomy can be adopted safely with good outcomes irrespective of annual center resection volume.  相似文献   
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