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81.
A second group of hepatitis C viruses   总被引:7,自引:0,他引:7  
cDNA clone 11–7 was isolated by immunoscreening a cDNA library that was prepared from a pooled plasma of non-A non-B hepatitis (NANBH) patients using expression vector gt 11. This cDNA corresponds to known nucleotide positions 3983–4745 of the genome of hepatitis C virus (HCV). This clone was used as a probe for screening the HCV-related cDNAs in a cDNA library similarly prepared by using gt 10. As a result, six more cDNA clones were isolated and analyzed for their nucleotide sequences. The results strongly suggested that there are at least two groups of HCV, group I and group II. According to our classification, the prototype HCV and clone 11–7 belong to group I HCV, and their nucleotide and deduced amino acid sequences were diverged from those of group II HCV. Genetic variation observed in the nucleotide and the amino acid sequences between the two groups resembles that in the NS3 region of the genome between Japanese encephalitis virus and West Nile fever virus. Polypeptides produced inEscherichia coli carrying a clone 11–7 or a group II cDNA clone E reacted with antibodies in the blood of 12 or 4 out of 14 individual chronic NANBH patients, respectively. Our data clearly indicate the existence of a second group of HCV.  相似文献   
82.
Citrin is a mitochondrial aspartate glutamate carrier primarily expressed in the liver, heart, and kidney. We found that adult-onset type II citrullinemia is caused by mutations in the SLC25A13 gene that encodes for citrin. In this report, we describe the frequency of SLC25A13 mutations, the roles of citrin as a member of the urea cycle and as a member of the malate-aspartate shuttle, the relationship between its functions and symptoms of citrin deficiency, and therapeutic issues.  相似文献   
83.
84.
AIMS: To investigate the presence of iron in biopsy and resection specimens from the stomach of patients with hepatic cirrhosis of various aetiologies. METHODS: Among 753 patients who had been admitted to the hospital with liver cirrhosis from 1984 to 2002, and 723 patients who underwent liver biopsy or liver resection from 1990 to 2003, 426 patients with concomitant gastric biopsy or gastrectomy were selected for study. Formalin fixed, paraffin wax embedded tissues of the stomach and the liver (when available) were retrieved from the pathology files of Kariya General Hospital, Japan. Haematoxylin and eosin staining and Perls' stain were performed for all the available tissues and haemosiderin and its localisation were examined. RESULTS: In total, 78 patients-72 of those with cirrhosis (26%) and six without cirrhosis (4%)-showed accumulation of haemosiderin. Regardless of aetiology, patients with clinical varices showed more frequent haemosiderin accumulation (40%) than patients without varices (19%). For patients with cirrhosis, there were no significant differences in the positive rate between those with (28%) or without (23%) hepatocellular carcinoma. CONCLUSION: The significant increase in haemosiderin deposition in the gastric glands of patients with cirrhosis suggests that the assessment of iron deposition in gastric biopsy specimens may have predictive value in controlling patients with cirrhosis.  相似文献   
85.
Complement activation products are major components of the inflammatory response induced by cardiac surgery and cardiopulmonary bypass which contribute to postoperative organ dysfunction, fluid accumulation, and morbidity. Activation of the complement system occurs during extracorporeal circulation, during reperfusion of ischemic tissue, and after the formation of heparin-protamine complexes. In this study we examine the efficacy of Compstatin, a recently discovered peptide inhibitor of complement, in preventing heparin/protamine-induced complement activation in baboons. The study was performed in baboons because Compstatin binds to baboon C3 and is resistant to proteolytic cleavage in baboon blood (similar to humans); Compstatin inhibits only the activation of primates' complement system. After testing various doses and administration regimens, Compstatin produced complete inhibition at a total dose of 21 mg/kg when given as a combination of bolus injection and infusion. Compstatin completely inhibited in vivo heparin/protamine-induced complement activation without adverse effects on heart rate or systemic arterial, central venous, and pulmonary arterial pressures. This study indicates that Compstatin is a safe and effective complement inhibitor that has the potential to prevent complement activation during and after clinical cardiac surgery. Furthermore, Compstatin can serve as the prototype for designing an orally administrated drug.  相似文献   
86.
Polymerase chain reaction (PCR) is a technique to amplify only a specific segment of DNA without using a plasmid or a phage vector. It is a powerful tool for genetic analysis of various diseases including inherited and viral diseases, and is now being applied to clinical diagnosis. Here, presented are several methods using PCR mainly for diagnosis of hemoglobinopathy which we have been engaged in. Some other diseases are also included.  相似文献   
87.
We describe a five-month-old male infant with Coffin-Siris syndrome, the so-called Dandy-Walker variant (hypoplasia of the cerebellar vermis with cystic dilatation of the fourth ventricle, but without enlargement of the posterior fossa), and partial agenesis of the corpus callosum. Dandy-Walker malformation and mega cisterna magna, but not Dandy-Walker variant, have been reported in Coffin-Siris syndrome. The presence of Dandy-Walker variant in the infant we described confirms that the full continuum of the Dandy-Walker complex can occur in Coffin-Siris syndrome. The yet unidentified gene(s) for the syndrome may be related to the development of the hindbrain.  相似文献   
88.
89.
Summary Marek's disease virus (MDV)-infected chickens show thymic atrophy during the acute phase of infection. We examined whether the thymic atrophy by MDV-infection was mediated by apoptosis. Apoptosis-specific DNA ladderings were clearly observed in thymocytes one week after MDV-infection. Histological and flow cytometry studies revealed that immature CD4+CD8+ thymocytes underwent apototic cell death. In addition, the expression level of CD8 molecules on both CD4CD8+ and CD4+CD8+ thymocyte populations was down-regulated in the infected chickens. These thymic changes might be involved in the pathogenesis of Marek's disease.  相似文献   
90.
A patient homozygous for the SCA6 gene with retinitis pigmentosa   总被引:1,自引:0,他引:1  
The present authors studied a 55-year-old-patient homozygous for the SCA6 gene who experienced frequent attacks of positional vertigo at 37 years of age with subsequent staggering gait and night blindness. Retinitis pigmentosa (RP), as well as cerebellar ataxia and vertical antidirectional nystagmus, were detected. The subject's parents were first cousins, and two of his three male cousins, whose parents were also first cousins, had RP without ataxia or nystagmus. The numbers of CAG repeats in the expanded alleles of the SCA6 gene found by molecular analysis were 21 and 21. The genetic results were negative for SCA1, SCA2, SCA3, SCA7 and dentatorubral pallidoluysian atrophy. The retinal degeneration in this patient is most likely to be secondary to a genetic disorder of autosomal or X-linked recessive inheritance rather than SCA6. Other reported cases of patients homozygous for the SCA6 gene are also reviewed.  相似文献   
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