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71.
72.
Cryptogenic cirrhosis (CC) is diagnosed in 5-30% of cirrhotic patients overall and 7% of patients who undergo liver transplantation for cirrhosis. In our series of patients transplanted for CC, pre-transplant clinical and histological data and the post-transplant course were reexamined in an attempt to identify the aetiology. Among the 881 patients transplanted in our centre between 1987 and 2000, 28 patients with a median age of 46 yr (range: 18-69) at transplantation were initially classified as having CC. Two patients were excluded because of intense ischaemic lesions caused by chemoembolization prevented histological analysis of the native liver (n = 1) and because of cryptic HBV infection (n = 1). Among the remaining 26 patients, four groups were individualized: (i) patients with chronic inflammatory liver disease with autoimmune features (n = 14, 54%); (ii) patients with features suggestive of non-alcoholic fatty liver disease (n = 3, 11.5%); (iii); patients with incomplete septal cirrhosis (ISC) and vascular liver disease (n = 3), and (iv) patients with unresolved CC (n = 6, 23%). In the autoimmune liver disease group, the median International Autoimmune Hepatitis score was 12.5 (range: 11-19) after reevaluation and review of the post-transplantation course was helpful to confirm the diagnosis with the occurrence of active graft hepatitis in nine patients, with autoantibodies in five patients. The vascular group was characterized by lesions of obliterative portal venopathy and ISC in all native livers. Diagnosis of NAFLD was based on the clinical background of obesity and/or type 2 diabetes and the presence of steatosis or steatohepatitis in native livers and graft biopsies. A definite aetiological diagnosis can be achieved in the majority of patients initially diagnosed with CC. Autoimmune liver disease emerged as the main aetiology (14 of 26 patients, 54%) and frequently recurred on the grafted liver (nine cases). In all cases a precise diagnosis is obviously of practical interest for better management of post-transplant survey and treatment.  相似文献   
73.
The aim of the present study was to evaluate the relation between iron status and cancer in a population of middle-aged adults living in France where iron supplementation and iron-fortified foods are rarely used. The SU.VI.MAX study is a randomized, double-blind, placebo-controlled primary prevention trial evaluating the effect of antioxidant supplementation on chronic diseases in women aged 35-60 and men aged 45-60 y. At baseline, concentrations of hemoglobin, serum transferrin and serum ferritin were measured in 10,197 subjects. Data on dietary intake were estimated from six 24-h dietary records completed during the first 2 study years and available for 5287 subjects. All cancer cases that occurred during the 7.5-y follow-up were validated. In men, baseline serum transferrin and serum ferritin concentrations did not differ between subjects with cancers (n = 467) and those without. In women, serum ferritin was higher (P < 0.0001) and serum transferrin tended to be lower (P < 0.08) in cancer cases. Iron status was not related to cancer risk in men, but women with serum ferritin concentrations > 160 microg/L had an increased risk of cancer (odds ratio = 1.88, 95% CI: 1.05,3.35). No relation was found between dietary iron intake and risk of all cancer sites combined for either men or women. Our results suggest that iron status is not a predictor of cancer risk in men, whereas a serum ferritin concentration > 160 microg/L may be associated with an increase in cancer risk in women.  相似文献   
74.
Therapeutic roles of peroxisome proliferator-activated receptor agonists   总被引:28,自引:0,他引:28  
Staels B  Fruchart JC 《Diabetes》2005,54(8):2460-2470
Peroxisome proliferator-activated receptors (PPARs) play key roles in the regulation of energy homeostasis and inflammation, and agonists of PPARalpha and -gamma are currently used therapeutically. Fibrates, first used in the 1970s for their lipid-modifying properties, were later shown to activate PPARalpha. These agents lower plasma triglycerides and VLDL particles and increase HDL cholesterol, effects that are associated with cardiovascular benefit. Thiazolidinediones, acting via PPARgamma, influence free fatty acid flux and thus reduce insulin resistance and blood glucose levels. PPARgamma agonists are therefore used to treat type 2 diabetes. PPARalpha and -gamma agonists also affect inflammation, vascular function, and vascular remodeling. As knowledge of the pleiotropic effects of these agents advances, further potential indications are being revealed, including roles in the management of cardiovascular disease (CVD) and the metabolic syndrome. Dual PPARalpha/gamma agonists (currently in development) look set to combine the properties of thiazolidinediones and fibrates, and they hold considerable promise for improving the management of type 2 diabetes and providing an effective therapeutic option for treating the multifactorial components of CVD and the metabolic syndrome. The functions of a third PPAR isoform, PPARdelta, and its potential as a therapeutic target are currently under investigation.  相似文献   
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Alzheimer's disease (AD) is the most common cause of dementia. It is characterized by beta-amyloid (A beta) plaques, neurofibrillary tangles and the degeneration of specifically vulnerable brain neurons. We observed high expression of the cholesterol 25-hydroxylase (CH25H) gene in specifically vulnerable brain regions of AD patients. CH25H maps to a region within 10q23 that has been previously linked to sporadic AD. Sequencing of the 5' region of CH25H revealed three common haplotypes, CH25Hchi2, CH25Hchi3 and CH25Hchi4; CSF levels of the cholesterol precursor lathosterol were higher in carriers of the CH25Hchi4 haplotype. In 1,282 patients with AD and 1,312 healthy control subjects from five independent populations, a common variation in the vicinity of CH25H was significantly associated with the risk for sporadic AD (p = 0.006). Quantitative neuropathology of brains from elderly non-demented subjects showed brain A beta deposits in carriers of CH25Hchi4 and CH25Hchi3 haplotypes, whereas no A beta deposits were present in CH25Hchi2 carriers. Together, these results are compatible with a role of CH25Hchi4 as a putative susceptibility factor for sporadic AD; they may explain part of the linkage of chromosome 10 markers with sporadic AD, and they suggest the possibility that CH25H polymorphisms are associated with different rates of brain A beta deposition.  相似文献   
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Congenital erythropoietic porphyria (CEP; Günther disease; OMIM 263700) is a rare autosomal recessive disorder caused by a deficiency of uroporphyrinogen III synthase (UROS). The deficiency of this enzyme is associated with lifelong overproduction of series I porphyrins which circulate and are deposited in many tissues, causing light-sensitisation and severe damage to skin beginning in childhood. Blistering and scarring of exposed areas may lead to mutilating deformities. We describe two cases: a 4-year-old boy and his first cousin who were cured of CEP by matched unrelated donor bone marrow transplants. Both are alive and disease-free 3 and 2 years post-transplant, respectively. Cutaneous lesions improved dramatically. The correction of the enzyme deficiency was confirmed by measuring erythrocyte UROS activity and urinary porphyrin excretion. Chimerism was complete for both children. Both patients were homoallelic for a novel mutation of the UROS gene, the missense mutation A69T. Conclusion:Considering the severity of the disease, if HLA-matched sibling donor is not available, haematopoietic stem cell transplantation using a matched unrelated donor should be strongly considered for treating congenital erythropoietic porphyria since this is currently the only known curative therapy.  相似文献   
80.
Chondrocalcinosis, chronic pseudo-osteoarthritis arthropathy, and osteoporosis are classic osteoarticular complications of hemochromatosis (HC). Within HC, femoral head aseptic osteonecrosis (FHAO) is not notified in textbooks. We describe 3 cases of FHAO occurring in this setting in 3 patients homozygous for the C282Y mutation on HFE gene who had no other risk factors for FHAO. FHAO was diagnosed 9 years before (Case 1), concomitantly with (Case 3), or 9 years after HC (Case 2). In one case, FHAO occurred although phlebotomies were regularly carried out. There are scarce data available in the literature on HC and FHAO. Our observations suggest FHAO may be an indicator for HC, and iron balance should be determined before considering FHAO as idiopathic. Thus phlebotomy may not be protective against the occurrence of FHAO. Studies are needed to determine the prevalence of HC in consecutive patients with FHAO.  相似文献   
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