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Gene conversion is a likely cause of mutation in PKD1   总被引:3,自引:0,他引:3  
Approximately 70% of the gene responsible for the most common form of autosomal dominant polycystic kidney disease ( PKD1 ) is replicated in several highly homologous copies located more proximally on chromosome 16. We recently have described a novel technique for mutation detection in the duplicated region of PKD1 that circumvents the difficulties posed by these homologs. We have used this method to identify two patients with a nearly identical cluster of base pair substitutions in exon 23. Since pseudogenes are known to be reservoirs for mutation via gene conversion events for a number of other diseases, we decided to test whether these sequence differences in PKD1 could have arisen as a result of this mechanism. Using changes in restriction digest patterns, we were able to show that these sequence substitutions are also present in N23HA, a rodent-human somatic cell hybrid that contains only the PKD1 homologs. Moreover, these changes were also detected in total DNA from several affected and unaffected individuals that did not harbor this mutation in their PKD1 gene copy. This is the first example of gene conversion in PKD1 , and our findings highlight the importance of using gene-specific reagents in defining PKD1 mutations.   相似文献   
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Brain injury in amateur soccer players   总被引:1,自引:0,他引:1  
Grote C  Donders J 《JAMA》2000,283(7):882-883
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ObjectiveTo compare efficacy and tolerability between different regimens of rifaximin vaginal tablets and a placebo for treatment of bacterial vaginosis.MethodsIn a prospective study carried out at 13 sites in 3 European countries between August 2009 and October 2010, White, non-pregnant, premenopausal women with bacterial vaginosis were randomly assigned to receive rifaximin at 100 mg for 5 days (100 mg/5 days), 25 mg/5 days, or 100 mg/2 days, or placebo. Women were assessed at 7–10 and 28–35 days. Diagnosis and cure were based on Amsel criteria and Nugent score. Fisher exact test was used to compare cure rates.ResultsAmong 114 women recruited, 103 were evaluable for drug efficacy. Therapeutic cure rate at first follow-up was higher in the rifaximin 25 mg/5 days (48%, P = 0.04), 100 mg/2 days (36.0%), and 100 mg/5 days (25.9%) groups than in the placebo group (19.0%). At second follow-up, therapeutic cure rate was 28.0%, 14.8%, and 4.0% in the respective groups versus 7.7% in the placebo group. No difference in adverse events was observed.ConclusionRifaximin at 25 mg/5 days showed better therapeutic cure rates and maintenance of therapeutic cure after 1 month versus placebo. All treatment regimens were well tolerated.EudraCT number: 2009-011826-32.  相似文献   
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The aim of this study is the evaluation of a simple surgical widening plasty of the posterior vestibulum for central introital dyspareunia. This study takes place in gynecological infectious diseases clinic in secondary and tertiary care centers. The subjects are one hundred forty-five consecutive patients with introital pain during or when attempting sexual intercourse. One-digit examination of the posterior hymenal rim of the vulva elicits the specific pain and clinical examination reveals nothing abnormal or only focal redness on the central posterior vestibulum. This condition should be clearly differentiated from the focal-provoked vestibulodynia, although mixed forms are frequent. A questionnaire was composed to assess the level of pain experienced during intercourse and of satisfaction of their sexual life in general at 1 to 3?years after the intervention. After a mean of 3?years, 90% of the patients were very satisfied with the improvement of the sexual health due to the intervention. Eighty percent had less pain during intercourse. The proportion of patients forced to interrupt sexual intercourse because of pain dropped from 64% to 26% (p?<?0.0001). The number of women only having infrequent intercourse (once a month or less) decreased more than fourfold and the mean number of occasions that sexual intercourse took place increased by 27% after the intervention. Simple surgical widening plasty of the posterior vestibulum without excision of tissue led to a significant improvement of the sex life of at least 80% of a group of women with primary and secondary central introital dyspareunia of any cause. Correct and specific diagnosis is crucial prior to any intervention.  相似文献   
7.
BACKGROUND & AIMS: Shwachman syndrome is an inherited condition with multisystemic abnormalities, including exocrine pancreatic dysfunction. The aim of this study was to evaluate the occurrence and progression of features in a large cohort of patients. METHODS: Clinical records of 25 patients with Shwachman syndrome were reviewed. RESULTS: Mean birth weight (2.92 +/- 0.51 kg) was at the 25th percentile. However, by 6 months of age, mean heights and weights were less than the 5th percentile. After 6 months of age, growth velocity was normal. Severe fat maldigestion due to pancreatic insufficiency was present in early life (fecal fat, 26% +/- 17% of fat intake; age, < 2 years). Serial assessment of exocrine pancreatic function showed persistent deficits of enzyme secretion, but 45% of patients showed moderate age-related improvements leading to pancreatic sufficiency. Neutropenia was the most common hematologic abnormality (88%), but leukopenia, thrombocytopenia, and anemia were also frequently encountered. Patients with hypoplasia of all three bone marrow cellular lines (n = 11) had the worst prognosis; 5 patients died, 2 of sepsis and 3 of acute myelogenous leukemia. Other findings included hepatomegaly and/or abnormal liver function test results and skeletal abnormalities. CONCLUSIONS: A wide and varied spectrum of phenotypic abnormalities among patients with Shwachman syndrome is described. Pancreatic acinar dysfunction is an invariable abnormality. Patients with severe bone marrow involvement may have a guarded prognosis. (Gastroenterology 1996 Dec;111(6):1593-602)  相似文献   
8.
Vezza  R; Roberti  R; Nenci  GG; Gresele  P 《Blood》1993,82(9):2704-2713
Prostaglandin E2 (PGE2) is produced by activated platelets and by several other cells, including capillary endothelial cells. PGE2 exerts a dual effect on platelet aggregation: inhibitory, at high, supraphysiologic concentrations, and potentiating, at low concentrations. No information exists on the biochemical mechanisms through which PGE2 exerts its proaggregatory effect on human platelets. We have evaluated the activity of PGE2 on human platelets and have analyzed the second messenger pathways involved. PGE2 (5 to 500 nmol/L) significantly enhanced aggregation induced by subthreshold concentrations of U46619, thrombin, adenosine diphosphate (ADP), and phorbol 12-myristate 13-acetate (PMA) without simultaneously increasing calcium transients. At a high concentration (50 mumol/L), PGE2 inhibited both aggregation and calcium movements. PGE2 (5 to 500 nmol/L) significantly enhanced secretion of beta-thromboglobulin (beta TG) and adenosine triphosphate from U46619- and ADP-stimulated platelets, but it did not affect platelet shape change. PGE2 also increased the binding of radiolabeled fibrinogen to the platelet surface and increased the phosphorylation of the 47-kD protein in 32P- labeled platelets stimulated with subthreshold doses of U46619. Finally, the amplification of U46619-induced aggregation by PGE2 (500 nmol/L) was abolished by four different protein kinase C (PKC) inhibitors (calphostin C, staurosporine, H7, and TMB8). Our results suggest that PGE2 exerts its facilitating activity on agonist-induced platelet activation by priming PKC to activation by other agonists. PGE2 potentiates platelet activation at concentrations produced by activated platelets and may thus be of pathophysiologic relevance.  相似文献   
9.
Ball  ED; Mills  LE; Coughlin  CT; Beck  JR; Cornwell  GG d 《Blood》1986,68(6):1311-1315
Second or third chemotherapy-induced remissions in acute myelogenous leukemia (AML) are limited by early relapse of the leukemia. We developed monoclonal antibodies (MoAbs) that are cytotoxic to myeloid leukemia cells to treat bone marrow from these patients ex vivo for autologous transplantation. In this pilot study, bone marrow was harvested from ten patients with AML in remission, treated with one or two complement-fixing MoAbs, PM-81 and AML-2-23, which react with myeloid differentiation antigens, incubated with rabbit complement, and cryopreserved. These MoAbs were chosen because they have broad reactivity with AML cells but not with pluripotent progenitor cells. At the time of transplant, 6 patients were in second complete remission, 1 each was in third complete or partial remission, and 2 were in early first relapse. The patients were treated with cyclophosphamide (60 mg/kg a day for 2 days) and total body irradiation (200 cGy twice a day for 3 days) and given infusions of MoAb-treated bone marrow. Full bone marrow reconstitution was observed in eight patients; two patients did not recover platelets. Seven of the ten patients are surviving and disease-free at 21.0, 15.0, 13.0, 10.0, 6.0, 3.0, and 2.0 months posttransplant. Treating bone marrow with MoAbs to myeloid differentiation antigens does not interfere with pluripotential stem cell engraftment. Longer follow-up and a controlled study are necessary to prove that the apparent efficacy of this therapeutic approach in some patients is attributable to MoAb-mediated killing of leukemia cells.  相似文献   
10.
The healthy vaginal microbiota is generally dominated by lactobacilli that confer antimicrobial protection and play a crucial role in health. Bacterial vaginosis (BV) is the most prevalent lower genital tract infection in women in reproductive age and is characterized by a shift in the relative abundances of Lactobacillus spp. to a greater abundance of strictly anaerobic bacteria. In this study, we designed a new phylogenetic microarray-based tool (VaginArray) that includes 17 probe sets specific for the most representative bacterial groups of the human vaginal ecosystem. This tool was implemented using the ligase detection reaction-universal array (LDR-UA) approach. The entire probe set properly recognized the specific targets and showed an overall sensitivity of 6 to 12 ng per probe. The VaginArray was applied to assess the efficacy of rifaximin vaginal tablets for the treatment of BV, analyzing the vaginal bacterial communities of 22 BV-affected women treated with rifaximin vaginal tablets at a dosage of 25 mg/day for 5 days. Our results showed the ability of rifaximin to reduce the growth of various BV-related bacteria (Atopobium vaginae, Prevotella, Megasphaera, Mobiluncus, and Sneathia spp.), with the highest antibiotic susceptibility for A. vaginae and Sneathia spp. Moreover, we observed an increase of Lactobacillus crispatus levels in the subset of women who maintained remission after 1 month of therapy, opening new perspectives for the treatment of BV.  相似文献   
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