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WT1 mutations have been considered a rare cause of nephrotic syndrome but recent reports challenge this assumption. Exclusion of inherited forms is a basic point in any therapeutic strategy to nephrotic syndrome since they do not respond to drugs. We screened for WT1 mutations in 200 patients with nephrotic syndrome: 114 with steroid resistance (SRNS) and 86 with steroid dependence (SDNS) for whom other inherited forms of nephrotic syndrome (NPHS2, CD2AP) had been previously excluded. Three girls out of 32 of the group with steroid resistance under 18 years presented classical WT1 splice mutations (IVS9+5G>A, IVS9+4C>T) of Frasier syndrome. Another one presented a mutation coding for an amino acid change (D396N) at exon 9 that is typical of Denys-Drash syndrome. All presented resistance to drugs and developed end stage renal failure within 15 years. Two girls of the Frasier group presented a 46 XY karyotype with streak gonads while one was XX and had normal gonad morphology. In the two cases with IVS9+5G>A renal pathology was characterized by capillary wall thickening with deposition of IgG and C3 in one that was interpreted as a membrane pathology. Foam cells were diffuse in tubule-interstitial areas. In conclusion, WT1 splice mutations are not rare in females under 18 years with SRNS. This occurs in absence of a clear renal pathology picture and frequently in absence of phenotype change typical of Frasier syndrome. In adults and children with SDNS, screening analysis is of no clinical value. WT1 hot spot mutation analysis should be routinely done in children with SRNS; if the molecular screening anticipates any further therapeutic approach it may modify the long term therapeutic strategy.Filippo Aucella and Luigi Bisceglia contributed equally to the work.  相似文献   
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The Authors report their experience with the surgical treatment of incisional hernias over the period from July 2000 to June 2004 in the Division of General Surgery of the Department of Surgical Sciences of the University of Foggia where 22 patients were operated on. Nine of them had an incisional hernia of considerable size, while in the other 13 patients the hernia was less voluminous. The authors emphasise the essential role of synthetic prostheses (polypropylene) which now replace and supersede the reabsorbable ones which have fallen into disuse due to the lack of guarantees regarding their strength over lengthy periods. An interdisciplinary approach is now mandatory for a pathology which requires the contribution of many different healthcare operatives such as cardiologists, respiratory physiopathologists, physiokinesitherapists, endocrinologists and resuscitators who all share in the work of the surgeon who represents the last link in the chain and has the technical task of resolving the basic pathology. The technique adopted for the larger incisional hernias was a Ramirez abdominoplasty, the first step of which consists in a very meticulous separation of the different structures of the abdominal wall followed by synthesis of the different anatomical layers with the application of polypropylene meshes. Our results in terms of intra- and postoperative mortality, complicating diseases and hospitalisation are compared with those reported in other studies using the Rives technique.  相似文献   
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Dependable methods were developed for preimplantation sexing of human IVF embryos, for use in clinical settings where prospective parents are at high risk for transmission of X-linked diseases. Using single cultured cells and blastomeres from human embryos as model systems, a multiplex protocol was developed for rapid analysis via nested polymerase chain reaction (PCR). Reliability was enhanced by co-amplification of conserved amelogenin gene segments from both X and Y chromosomes, as well as Y-linked DYZ1 repetitive elements. Each cell was manually isolated and individually washed to avoid potential contaminants. Multiplex amplification allowed recognition of spurious amplification failures specific to particular amelogenin single-copy targets. The X-linked internal control and multiple Y-linked markers allowed recognition and exclusion of most aberrant samples, thus averting potential misdiagnosis. The optimized single-cell protocol reduced experimental sexing errors to < 2% (1/60), but also revealed potential pitfalls of single-cell analysis. With human triploid embryos, separate sampling of individual blastomeres provided concordant female or male signals. Slight modification adapted the procedure for diagnosis of biopsy material from blastocyst stage embryos, allowing separate analysis of multiple tubes containing multiple cells for improved reliability.  相似文献   
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Cell-cycle deregulation is an early event of hepatocarcinogenesis. We evaluated the role of changes in activity of nuclear factor kappaB (NF-kappaB) and some related pathways in this alteration, and the interference of N-(4-hydroxyphenyl)retinamide (HPR), a retinoid chemopreventive for various cancer types, with these molecular mechanisms and the evolution of preneoplastic liver to cancer. Male F344 rats, initiated according to the 'resistant hepatocyte' model of liver carcinogenesis, received weekly 840 nmol of liposomal HPR (SL-HPR)/100 g body wt or empty liposomes, between 5 and 25 weeks after initiation. Inhibition of DNA synthesis and induction of apoptosis occurred in pre-cancerous lesions, 7-147 days after starting SL-HPR, and a decrease in carcinoma incidence and multiplicity was observed 25 weeks after arresting treatment. An increase in NF-kappaB expression and binding activity, and under-expression of the inhibitor kappaB-alpha (IkappaB-alpha) were found in preneoplastic liver and neoplastic nodules, 5 and 25 weeks after initiation, respectively. These lesions also showed low expression of Mat1A and low activity of methionine adenosyltransferase I/III, whose reaction product, S-adenosyl-l-methionine, enhances IkappaB-alpha expression. SL-HPR prevented these changes and induced a decrease in expression of iNos, c-myc, cyclin D1 and Vegf-A genes, that were over-expressed in preneoplastic liver and nodules, and a decrease in Bcl-2/Bax, Bcl-2/Bad and Bcl-xL/Bax mRNA ratios with respect to the lesions of control rats. Liposomes alone did not influence the parameters tested. These results indicate that signal transduction pathways controlled by NF-kappaB, nitric oxide and S-adenosyl-l-methionine are deregulated in pre-cancerous lesions. Recovery from these alterations by SL-HPR is associated with chemoprevention of hepatocarcinogenesis. Overall, these studies elucidate some molecular changes, in early stages of hepatocarcinogenesis, and underline their pathogenetic role. Moreover, they demonstrate a partially new mechanism of HPR chemopreventive effect and indicate the potential clinical relevance of this compound for prevention of hepatocellular carcinoma.  相似文献   
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Botulism is a rare neuroparalytic disease caused by a potent neurotoxin produced by Clostridium botulinum. There are different clinical types of botulism. Early diagnosis of the condition is essential for effective treatment. We report a case of food-borne botulism in identical twins characterized by severe initial oral involvement and a review of the literature about the condition.  相似文献   
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