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991.
Genetic hemochromatosis is an autosomal recessive disorder characterized by iron overload and a variety of clinical manifestations such as liver cirrhosis and arthropathy. It is the most common genetic disease of northern European populations. The principal gene responsible for hereditary hemochromatosis, designated HFE, is located on chromosome 6 in the HLA region. The single point mutation 845A, changing cysteine at position 282 to tyrosine (C282Y), in this gene has been identified as the main genetic basis of hereditary hemochromatosis. Two other mutations, 187G, a histidine to aspartate at amino acid 63 (H63D), and 193T, a serine to cysteine at amino acid 65 (S65C), appear to be associated with milder forms of hereditary hemochromatosis. There is a high prevalence of the C282Y mutation in northern European populations, whereas in those of the Mediterranean basin the prevalence seems low and almost absent in Far East countries. This mutation seems usually to occur on the ancestral haplotype 7.1. Accordingly, a Celtic origin of this mutation has been suggested. The aim of this study was to determine the frequency of HFE gene mutations in five geographic regions in Italy. Samples were tested for C282Y, H63D, and S65C mutations of the HFE gene according to methods of each laboratory and the results were standardized with the exchange of typed samples between the different laboratories. In addition, C282Y-positive DNA samples were typed for D6S105 allele 8 and HLA-A3 by ARMS-PCR. We have found that the allele frequency of the C282Y mutation decreases from northeast Italy (Friuli, 6%) to northwest Italy (Piedmont, 4.8%) and to central Italy (Emilia-Romagna, 1.7%). However, this mutation is lacking in the two regions of the Mediterranean basin's center (Sicily and Sardinia). Accordingly, a significant difference in the frequency of the mutation was observed between these Italian regions (P = 0.07 x 10(-3)). In contrast, no difference was observed in allele frequency of H63D in the five Italian regions. Finally, as regards the S65C mutation a very low frequency was observed in Friuli, Emilia-Romagna, and Sardinia, whereas in Sicily and Piedmont we have not found this mutation. In conclusion, these data are consistent with the hypothesis that the C282Y mutation occurred in Caucasian populations of Celtic origin, whereas the H63D mutation is more ancient as demonstrated by the ubiquitous distribution.  相似文献   
992.
Summary The authors report data obtained from a 3-year study of CSII and humanized insulin (semi-synthetic human insulin) administered to 18 insulin-dependent subjects in the outpatient clinic. The aim of this study was to evaluate the validity of insulin pumps in long-term treatment. Metabolic parameters were significantly improved (p<0.001) in the first month and remained so with only slight alterations throughout treatment. The authors underline some metabolic problems (ketosis) caused by malfunctioning of the insulin pumps, by the difficulties with the infusion sytem or by nodular skin lesions at the infusion site. Only these lesions called for treatment to be discontinued in 4 patients. The highest incidence of nodular skin lesions was seen after one year’s uninterrupted treatment and they seem connected to the duration of treatment rather than to the patients’ negligence (inadequate hygiene, delayed needle substitution). The authors conclude that CSII treatment is valid over short-term periods, whereas it presents drawbacks over long-term administration.  相似文献   
993.
In both animal and human studies, ethanol seems to modulate host immune function. In a variety of animal studies, ethanol has been shown to decrease lymphocyte function and number. In human studies of patients with alcoholic hepatitis, these abnormalities were also seen with specific correlation with protein malnutrition. Hepatic pathological lesions were also correlated with lymphocyte subset infiltration. However, peripheral blood lymphocytes did not correlate consistently with hepatic histopathology.  相似文献   
994.
BACKGROUND AND OBJECTIVES: Cardiac resynchronization via left ventricular or biventricular pacing is an option for selected patients with ventricular systolic dysfunction and widened QRS complex. Stimulation through a coronary vein is the technique of choice for left ventricular pacing, but this approach results in a failure rate of approximately 8%. We describe our initial experience with minimally invasive surgical implantation of left ventricular epicardial leads using video-assisted thoracoscopy. PATIENTS AND METHOD: A total of 14 patients with congestive heart failure, NYHA functional class 3.2 (0.6) and mean ejection fraction 22.9 (6.8)% were included in this study. Left bundle branch block, QRS complex >140 ms and abnormal septal motion were observed in all cases. Epicardial leads were implanted on the left ventricular free wall under general anesthesia using video-assisted thoracoscopic surgery. RESULTS: Lead implantation was successful in 13 patients. Conversion to a small thoracotomy was necessary in one patient. All patients were extubated in the operating room. None of the patients died during their hospital stay. Follow-up showed reversal of ventricular asynchrony and significant improvement in ejection fraction and functional class. CONCLUSIONS: Minimally invasive surgery for ventricular resynchronization using video-assisted thoracoscopy in selected patients is a safe procedure that makes it possible to choose the best site for lead implantation and provides adequate short- and medium-term stimulation.  相似文献   
995.
The aim of our study was to investigate whether haemophilia A patients with inversion of intron 22 are at high risk for non-inhibitory anti-FVIII antibodies development detected by ELISA. It is known that patients with severe forms of haemophilia A are more likely to develop anti-FVIII antibodies. The incidence of inhibitory anti-FVIII antibodies in patients with factor VIII gene inversion has been extensively evaluated, but if this defect has to be considered a predisposing factor is still debatable. Non-inhibitory anti-FVIII antibodies are attracting interest, due to the potential influence on FVIII half-life. Our data show that FVIII gene inversion was a major predisposing factor for anti-FVIII antibodies development.  相似文献   
996.
997.
Central nervous system (CSN) involvement in schistosomiasis is an ectopic manifestation with a large variety of clinical forms, including pseudotumoral, which occurs in isolated cases and is rare. Three patients with epidemiological indications of this pathology were examined; the clinical picture included lower-back pain irradiating to lower limbs, associated with progressive flaccid paraparesis and sphincterial disturbances in cases in which the spinal chord was involved; while in cases with encephalitic impairment, headache, dizziness and cerebellar syndrome, characterized by dysarthria and right-side dysgraphia, were present. Magnetic resonance imaging (MRI) showed a growing process in all cases; cerebrospinal fluid (CSF) characteristics and biological markers were compatible with neuroschistosomiasis (NS). Biopsy of the lesions confirmed this diagnosis in one case. After specific treatment with schistosomicides and corticosteroids, clinical, radiological and laboratorial improvement was observed.  相似文献   
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