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81.
Pancreaticobiliary maljunction is a congenital anomaly in which the junction between the pancreatic duct and the common bile duct is located outside the sphincter of Oddi. It is well known that pancreaticobiliary maljunction is frequently associated with carcinoma of thebiliary tract. We report a case of metachronous cancer of the gallbladder and pancreas associated with pancreaticobiliary maljunction and cystic dilatation of common bile duct in a 68-year-old Tunisian woman who underwent a cholecystectomy for acute cholecystitis. The pancreatic tumor was an adenosquamous carcinoma. Pancreaticobiliary maljunction allows for pancreatobiliary or biliopancreatic reflux which may induce biliary tract carcinoma. Few cases of multifocal cancer associated with this anomaly have been reported. The association with pancreatic carcinoma remains rare. Close attention should be given to both the biliary tract system and pancreas during the long-term follow-up of patients with pancreaticobiliary maljunction, especially after they have undergone a choledochojejunostomy.  相似文献   
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Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - The use of ingredients derived from natural sources has gained great attention in the cosmetic field,...  相似文献   
83.
To estimate the susceptibility to enterovirus infection and the frequency of long-term poliovirus excreters in Tunisian patients with primary immunodeficiencies (PIDs), enteroviruses were assessed in stool specimens of 82 patients with humoral, combined, and other PIDs. Isolated viruses were typed and intratyped by standard molecular techniques, and the whole VP1 region of poliovirus isolates was sequenced. Polioviruses were detected in 6 patients; all isolates were vaccine related. Five patients rapidly stopped excretion; one excreted a poliovirus type 1 isolate for several months, and the isolate accumulated up to 14 mutations in the VP1 region. Nonpolio enteroviruses were identified in 6 patients; 4 of them kept excreting the same strain for more than 6 months. The rate of enterovirus infection was 13.4% of the PID patients and 20.7% of those with an IgG defect; it greatly exceeded the rates generally found in Tunisian supposed-immunocompetent individuals (4.1% during the study period; P = 0.001 and P < 0.0001, respectively). Interestingly, patients with combined immunodeficiencies were at a higher risk for enterovirus infection than those with an exclusively B cell defect. A major histocompatibility complex (MHC) class II antigen expression defect was found in 54% of enterovirus-positive patients and in the unique long-term poliovirus excreter. The study results also suggest that substitutive immunoglobulin therapy may help clearance of a poliovirus infection and that most PID patients have the ability to stop poliovirus excretion within a limited period. However, the high susceptibility of these patients to enterovirus infection reinforces the need for enhanced surveillance of these patients until the use of oral poliovirus vaccine (OPV) is stopped.  相似文献   
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Acute chest syndrome is a frequent complication of sickle cell disease. This syndrome is characterized by recent infiltrate on chest X-ray with chest pain or fever or dyspnea. We report the case of a 26-year-old man in whom an acute chest syndrome with fat embolism was the inaugural sign of sickle cell disease. This report illustrates the frequency of potentially serious fat embolism in the acute chest syndrome and the importance of bronchoscopy and bronchoalveolar lavage (fatty macrophages) for determining the etiology of acute chest syndrome.  相似文献   
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OBJECTIVE: Autism is a complex, largely genetic psychiatric disorder. In the majority of cases, the cause of autism is not known, but there is strong evidence for a genetic etiology. To identify candidate genes, the physical mapping of balanced chromosomal aberrations is a powerful strategy, since several genes have been characterized in numerous disorders. In this study, the authors analyzed a balanced reciprocal translocation arising de novo in a subject with autism and mental retardation. METHOD: The authors performed the physical mapping of the balanced 9q23/10q22 translocation by fluorescent in situ hybridization experiments using bacterial artificial chromosome clones covering the areas of interest. RESULTS: Findings revealed that the KCNMA1 gene, which encodes the alpha-subunit of the large conductance Ca(2+)-activated K(+) (BK(Ca)) channel, a synaptic regulator of neuronal excitability, is physically disrupted. Further molecular and functional analyses showed the haploinsufficiency of this gene as well as decreased activity of the coded BK(Ca )channel. This activity can be enhanced in vitro by addition of a BK(Ca )channel opener (BMS-204352). Further mutational analyses on 116 autistic subjects led to the identification of an amino acid substitution located in a highly conserved domain of the protein not found in comparison subjects. CONCLUSIONS: These results suggest a possible association between a functional defect of the BK(Ca) channel and autistic disorder and raise the hypothesis that deficits in synaptic transmission may contribute to the physiopathology of autism and mental deficiency.  相似文献   
89.
Context Although steroid hormones produced by the adrenal gland play critical roles in human physiology, a detailed quantitative analysis of the steroid products has not been reported. The current study uses a single methodology (liquid chromatography–tandem mass spectrometry, LC‐MS/MS) to quantify ten corticosteroids in adrenal vein (AV) samples pre‐ and post‐adrenocorticotropic hormone (ACTH) stimulation. Design/methods Three men and six women with a diagnosis of an adrenal aldosterone‐producing adenoma (APA) were included in the study. Serum was collected from the iliac vein (IV) and the AV contralateral to the diseased adrenal. Samples were collected, before and after administration of ACTH. LC‐MS/MS was then used to quantify serum concentrations of unconjugated corticosteroids and their precursors. Results Prior to ACTH stimulation, the four most abundant steroids in AV were cortisol (90%), cortisone (4%), corticosterone (3%) and 11‐deoxycortisol (0·8%). Post‐ACTH administration, cortisol remained the major adrenal product (79%); however, corticosterone became the second most abundantly produced adrenal steroid (11%) followed by pregnenolone (2·5%) and 17α‐hydroxypregnenolone (2%). ACTH significantly increased the absolute adrenal output of all ten corticosteroids measured (P < 0·05). The four largest post‐ACTH increases were pregnenolone (300‐fold), progesterone (199‐fold), 17α‐hydroxypregnenolone (187‐fold) and deoxycorticosterone (82‐fold). Conclusion Using LC‐MS/MS, we successfully measured 10 corticosteroids in peripheral and AV serum samples under pre‐ and post‐ACTH stimulation. This study demonstrates the primary adrenal steroid products and their response to ACTH.  相似文献   
90.
HCV variants were classified into six genotypes (1–6) subdivided into several subtypes with different geographic distribution worldwide. Previous studies conducted in Tunisia showed that genotype 1 counts for more than 80 % of circulating HCV genotypes and most of the isolates belong to subtype 1b. Genotype 2 comes in the second position, however, few sequences have been analyzed and published. In the present study, 89 isolates from Tunisian patients, typed as genotype 2 by the InnoLIPA commercial probe hybridization test, were sequenced in the NS5B and Core/E1 regions. All the isolates, clustered with the genotype 2 reference sequences, in the NS5B and in the Core/E1 region and the phylogenetic analyses in the two genomic regions were perfectly concordant: subtype 2c was the most frequent (58 out of 89, 65.1 %) and few isolates belonged to subtypes 2k(n = 10), 2i(n = 5), and 2b(n = 1). Fifteen isolates did not match with any of the reference sequences representing the genotype 2 subtypes, identified up-to-date. They divided into 2 separate clusters with high bootstrap values in both genomic regions. This study shows perfect concordance between the NS5B and the Core/E1 region suggesting that any of the two regions can be used for genotyping and that intergenotypic and intragenotypic recombinants are not very frequent, at least for HCV isolates from genotype 2. The present study also shows a predominance of subtype 2c among genotype 2 HCV isolates circulating in Tunisia, the co-circulation of minor subtypes (2k, 2i, and 2b) and proposes the possible existence of two other new subtypes.  相似文献   
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