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1.
Although patients with inflammatory bowel disease (IBD) have reduced bone mass, there is controversy whether there is an increased risk of fracture. This study examines the risk of fracture and its predictors in patients with IBD. In a primary care- based nested case-control study, 231,778 fracture cases and 231,778 age- and sex-matched controls were recruited. A history of IBD was assessed from medical records. The prevalence of IBD was 156 and 282 per 100,000 for Crohn’s disease (CD) and ulcerative colitis (UC), respectively. Patients with IBD had an increased risk of vertebral fracture (odds ratio [OR], 1.72; 95% confidence interval [CI], 1.13-2.61) and hip fracture (OR, 1.59; 95% CI, 1.14-2.23). The risk of hip fracture was greater in patients with CD (OR, 1.86; 95% CI, 1.08-3.21) compared with UC (OR, 1.40; 95% CI, 0.92-2.13). Disease severity, assessed by the number of symptoms, predicted fracture even after adjusting for corticosteroid use (OR, 1.46; 95% CI, 1.04-2.04). Only 13% of patients with IBD who had already sustained a fracture were on any form of antifracture treatment. Patients with IBD have a higher risk of fracture due to both disease activity and use of oral corticosteroids. However, few of these patients are receiving optimal bone-sparing therapy, highlighting the importance of increasing awareness of osteoporosis in those managing these patients.  相似文献   

2.
: Iron overload may be carcinogenic. Patients with hereditary hemochromatosis (HH) are reportedly at a 20-200-fold risk of intrahepatic cancer, but the reported risks for nonhepatobiliary cancers are conflicting. The risk of cancer in heterozygous individuals (estimated allele frequency, 1/10 to 1/20) is unknown. This study aimed to better assess these risks. : We performed a population-based cohort study of 1847 Swedish patients with HH and 5973 of their first-degree relatives using nationwide, population-based health and census registers. We used standardized incidence ratios (SIRs) as relative risk. : With 62 liver cancers and 128 nonhepatobiliary cancers, patients with HH were at a 20-fold risk of liver cancer (SIR, 21; 95% confidence interval [CI], 16-22) but an almost unaltered risk of all other cancers (SIR, 1.2; 95% CI, 1.0-1.4), including nonelevated risks for several gastrointestinal tract cancers. At 10 years of follow-up, the absolute risk of liver cancer was 6% among men and 1.5% among women. With 21 liver cancers and 508 nonhepatobiliary cancers, first-degree relatives were at an unaltered risk of extrahepatic cancer (SIR, 1.0; 95% CI, 0.9-1.1, including unelevated risks for gastrointestinal cancers) but at a modest and historic increased risk of hepatobiliary cancer (SIR, 1.5; 95% CI, 1.0-2.4), the histopathologic spectrum of which differed from the patients. : Patients (particularly men) with HH are at increased risk for hepatocellular cancer, although the magnitude of the risk is lower than previous estimates. Overall cancer risk in first-degree relatives does not seem to be increased.  相似文献   

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: The heparin-binding growth factors fibroblast growth factor (FGF) and hepatocyte growth factor (HGF) are potent mitogens for hepatocellular carcinomas (HCCs). Heparin-binding growth factor signaling is regulated by sulfation of cell-surface heparan sulfate proteoglycans (HSPGs). We hypothesized that hSulf1, a recently described sulfatase, regulates growth signaling in HCCs. :Expression of hSulf1 in human HCC tumors was determined by real-time PCR. Down-regulation of hSulf1 expression was investigated by analyzing loss of heterozygosity (LOH) at the hSulf1 locus and the effect of the DNA methylation inhibitor 5-aza-deoxycytidine on hSulf1 expression. The subcellular location of hSulf1 and sulfation state of cell-surface HSPGs were assessed by immunocytochemistry. FGF and HGF signaling was examined by phospho-specific immunoblot analysis. Cell growth was measured by trypan blue exclusion, and the MTT assay and apoptosis were quantitated by fluorescence microscopy. :hSulf1 expression was decreased in 29% of HCCs and 82% of HCC cell lines. There was LOH at the hSulf1 locus in 42% of HCCs. Treatment with 5-aza-deoxycytidine reactivated hSulf1 expression in hSulf1-negative cell lines. Low hSulf1-expressing cells showed increased sulfation of cell-surface HSPGs, enhanced FGF and HGF-mediated signaling, and increased HCC cell growth. Conversely, forced expression of hSulf1 decreased sulfation of cell-surface HSPGs and abrogated growth signaling. HCC cells with high-level hSulf1 expression were sensitive to staurosporine- or cisplatin-induced apoptosis, whereas low expressing cells were resistant. Transfection of hSulf1 into hSulf1-negative cells restored staurosporine and cisplatin sensitivity. :Down-regulation of hSulf1 contributes to hepatocarcinogenesis by enhancing heparin-binding growth factor signaling and resistance to apoptosis.  相似文献   

5.
The most effective therapy currently available for treatment of chronic hepatitis C virus (HCV) is the combination of peginterferon and ribavirin. This study evaluated the effectiveness of this treatment in patients who were nonresponders to previous interferon-based therapy. The first 604 patients enrolled in the Hepatitis C Antiviral Long-Term Treatment Against Cirrhosis (HALT-C) Trial were evaluated. All were HCV RNA positive, previous nonresponders to interferon, with or without ribavirin, and had bridging fibrosis or cirrhosis on liver biopsy (Ishak fibrosis stage 3-6). Patients were retreated with peginterferon alfa-2a 180 μg/wk plus ribavirin 1000-1200 mg/day. Those with no detectable HCV RNA in serum at week 20 continued treatment for a total of 48 weeks and were then followed for an additional 24 weeks. Thirty-five percent of patients had no detectable HCV RNA in serum at treatment week 20, and 18% achieved sustained virologic response (SVR). Factors associated with an SVR included previous treatment with interferon monotherapy, infection with genotypes 2 or 3, a lower AST:ALT ratio, and absence of cirrhosis. Reducing the dose of ribavirin from ≥80% to ≤60% of the starting dose during the first 20 weeks of treatment was associated with a decline in SVR from 21% to 11% (P ≤ 0.05). In contrast, reducing the dose of peginterferon or reducing ribavirin after week 20, when HCV RNA was already undetectable, did not significantly affect SVR. Selected nonresponders to previous interferon-based therapy can achieve SVR following retreatment with peginterferon alfa-2a and ribavirin.  相似文献   

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An excess of smokers in patients with Crohn's disease (CD) and a paucity of smokers in patients with ulcerative colitis (UC) were reported in many studies. The aim of this study was to examine the association between smoking and inflammatory bowel disease (IBD) in Israel. Two independent studies were performed. Patients with recent IBD in comparison with matched population and outpatient controls and patients with chronic UC and CD were studied. Altogether, 475 subjects were investigated. In both studies, the presence of current smokers was lower in CD (9% and 18%) than in UC (24% and 26%). The proportions of nonsmokers in both studies were similar (UC, 61% and 65%; CD, 67% and 70%) and comparable to those found in their two control groups (57% and 61%; 63% and 68%, respectively) and to the general population of Israel. All differences in smoking habits between patient groups and their controls were not statistically significant, except for the paucity of current smokers in the small group of patients with newly diagnosed CD (P < 0.05). A matched analysis produced similar results. The expected associations between smoking and IBD could not be confirmed. Two hypotheses are considered: (1) the association between smoking and IBD may not be universal, and (2) our findings may be related to the higher genetic predisposition to IBD in Jewish people.  相似文献   

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ABSTRACT:N-rasmutations were examined in DNA samples extracted from the spleen of CBA/Ca mice that developed myeloid leukemia (ML) following exposure to radiations of different qualities. A total of 17 ML cases, i.e. 5 cases of neutron-induced and 12 cases of photon-(3 γ-ray and 9 x-ray) induced ML were included in the study along with 12 DNA samples from the bone marrow cells of control mice. Polymerase chain reaction-single strand conformational polymorphisms (PCR-SSCP) and the direct sequencing of PCR products were used to analyze three regions of theN-rasgene: (i) a 128 base-pair (bp) long portion of exon I (codons 2-37); (ii) a 103 bp long portion of exon II (codons 48-82); and (iii) a 107 bp long portion of exon III (codons 118-150). PCR-SSCP mobility shifts indicated mutations within only exon II of theN-rasgene. Such mutations were more prevalent in samples from mice exposed to fast neutrons. The exact type and location of these mutations were then determined by direct DNA sequencing. Silent point mutations, i.e. base transitions at the third base of codons 57 (GA→GA), 62 (CA→CA), or 70 (CA→CA) were present only in mice that developed ML after exposure to fast neutrons. A base transversion at the third base of codon 61 (CA→CA) was also observed in some ML cases. DNA sequencing demonstrated that ML samples contained normal as well as mutated DNA sequences. The higher frequency ofN-rasmutations in neutron-induced ML suggested that fast neutrons are more effective in inducing genomic instability at theN-rasregion of the genome. More importantly,N-rasmutations are not the initiating event in radiation leukemogenesis. This conclusion was supported by the finding thatN-rasmutations were detected only in mice with an overt leukemic phenotype but not in mice with minimal tissue infiltration of leukemic cells, suggesting that the disease may be present prior to the presence ofN-rasmutations. Alternatively,N-rasmay be present in these mice but a large number of normal spleen cells in these mice interferes with the detection of mutation in a small population of leukemic cells.  相似文献   

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Recent evidence suggests an active role of endothelial cells and inflammatory cells in radiation-induced vascular dysfunction and organ damage. The aim of this study was to characterize the endothelial cell-leukocyte interactions, their molecular mechanisms, and the associated microvascular dysfunction in postcapillary venules exposed to ionizing radiation. Leukocyte rolling, adherence, and emigration and leakage of fluorescein isothiocyanate albumin in rat mesenteric venules were measured in control conditions and at 2, 4, and 6 hours after abdominal irradiation. Some animals were treated with monoclonal antibodies against leukocyte (CD18) or endothelial cell (intercellular adhesion molecule 1, P-selectin) adhesion molecules before radiation and 5 hours thereafter. In comparison with controls, irradiated animals had a marked increase in the number of rolling leukocytes at 2 hours after radiation. In animals studied 6 hours after radiation, a significant increment in the number of adherent and emigrated leukocytes was observed. This was associated with an increased permeability to fluorescein isothiocyanate albumin. Treatment with antibodies against either CD18 or intercellular adhesion molecule 1, but not P-selectin, significantly attenuated leukocyte adherence, emigration, and the increase in permeability induced by radiation. Radiation-induced leukocyte adherence and emigration involves an interaction between CD11/CD18 on leukocytes and intercellular adhesion molecule 1 on vascular endothelium. These interactions are implicated in the early increase in vascular permeability after irradiation.  相似文献   

12.
The initial abnormalities in the renal sodium handling in patients with cirrhosis before developing ascites remain unknown. The aim of this study is to further characterize sodium metabolism and the effects of sodium loading in preascitic cirrhosis. Eight male, preascitic patients with cirrhosis and 6 volunteers had their daily urinary sodium excretion level measured while on a strictly metabolically controlled diet, first consisting of 20 mmol then of 200 mmol sodium per day each for 7 days. Central blood volume, plasma norepinephrine, and atrial natriuretic factor levels were measured during each diet. Preascitic patients with cirrhosis had significantly less daily urinary sodium excretion on both diets. Volume expansion in the patients with cirrhosis was indicated by significantly greater weight gain and higher atrial natriuretic factor levels for each diet. Patients with cirrhosis had central blood volume expansion (1725 ± 54 mL/m2) compared with controls (1495 ± 81 mL/m2; P = 0.03) on a low-sodium diet. This increased significantly in the controls (1864 ± 164 mL/m2; P = 0.04) on a high-sodium diet, associated with suppression of plasma norepinephrine, but not in the patients with cirrhosis (1679 ± 107 mL/m2; P > 0.05). Failure of further central blood volume expansion in the patients with cirrhosis on high-sodium diet in the presence of significant weight gain suggests maldistribution away from the effective arterial blood volume. This study provides further reasons why preascitic patients with cirrhosis might benefit from sodium restriction.  相似文献   

13.
The finding of antibodies against the polymerase of hepatitis B virus in renal dialysis patients before the incubation phase of infection implies underlying virus replication. Hence, the aim of the study was to test for virus during infection. Viremia was assayed in virus-infected and control patients using the polymerase chain reaction and Southern blotting. Six months before the appearance of surface antigen, most patients had detectable core region, but few patients were X region positive. Three months after surface antigen appeared, most carriers had detectable core and X products. Three years after surface antigen appeared, 5 of 8 carriers with persistent hepatitis B e antigen and 1 of 8 carriers with corresponding antibody had these products. Cloning and sequencing showed deletions within the X/precore region of viral DNA. Infection with X region mutants precedes that of wild-type virus, and they reappear after wild-type virus is eliminated in carriers.  相似文献   

14.
It is unclear whether tumor location, size, or the presence of multiple endocrine neoplasia type 1 (MEN-1) alters metastatic rate and survival in patients with pancreatic endocrine tumors. The purpose of this study was to determine the prognostic factors of survival and metastatic rate in patients with Zollinger-Ellison syndrome (ZES). Data were analyzed from 185 consecutive patients with ZES who were followed up prospectively. Liver metastases were present in 24% of patients and correlated with the size of the primary tumor. Duodenal tumors were smaller than pancreatic tumors. Liver metastases occurred more often (P < 0.00001) with pancreatic than duodenal tumors, whereas the metastatic rate to lymph nodes was not different. Survival of patients with liver but not lymph node metastases was shortened. In patients with sporadic ZES, liver metastases were more common during the initial evaluation and survival was decreased compared with patients with MEN-1; however, during follow-up, an equal percentage of patients with and without MEN-1 developed liver metastases. Survival was primarily determined by the presence of liver metastases. The frequency of liver metastases depends on the size and location of the primary tumor and on the presence of MEN-1 at the initial presentation. Metastases to the lymph nodes do not depend on these factors. A benign and malignant form of ZES exists.  相似文献   

15.
The pathogenesis of inherited intestinal cobalamin malabsorption (Gräsbeck-Imerslund disease) remains unknown. The authors studied whether the disease corresponds to a defective expression and/or function of the intrinsic factor-cobalamin receptor in the ileum. Intrinsic factor-cobalamin receptor activity was measured using radioisotope assay and gel-filtration exclusion chromatography in ileal biopsy specimens and urine concentrates from 4 patients with Gräsbeck-Imerslund disease and 5 controls. Receptor activity was 164 ± 13 fmol/mg of protein in control biopsy specimens and <2.6 fmol/mg protein in specimens from patients. The association constant was estimated to be 3.8 ± 0.4 (nmol/L)−1 in controls. A dramatic decrease in receptor activity was also observed in urine concentrate from patients with an association constant of 1.9 and 3.3 (nmol/L)−1. Isoelectrofocusing of the cross-linked intrinsic factor-cobalamin receptor complex showed an isoelectric point at 4.8 in a patient as well as in control samples. It is concluded that Gräsbeck-Imerslund disease is related to decreased intrinsic factor-receptor activity in intestinal mucosa; the receptor assay in urine can be helpful for diagnosis.  相似文献   

16.
Interferon can induce autoantibodies and autoimmune reactions. This study reviewed the clinical, serological, and HLA phenotypical features of patients who developed autoimmune hepatitis during interferon therapy for chronic hepatitis C, analyzing their response to immunosuppressive treatment. The diagnosis of chronic hepatitis C was based on positivity for viral RNA and a liver biopsy specimen obtained before interferon treatment. Sera were tested for autoantibodies by indirect immunofluorescence assay. HLA typing was performed by applying a standard microlymphocytotoxicity method. Of 144 patients with chronic hepatitis C treated with interferon, 7 women deteriorated during treatment; serum transaminase, γ-globulin, and immunoglobulin G levels increased; and serum autoantibodies became positive. Interferon was interrupted, a diagnosis of autoimmune hepatitis was established, and immunosuppressive therapy was initiated. All patients responded to this treatment. The 7 patients had similar HLA typing to those with autoimmune hepatitis, with DR4 in 2 patients (67%) with type 2 autoimmune hepatitis, and with DR3 and DR52 in 2 (50%) and 4 (100%) patients, respectively, with type 1 autoimmune hepatitis; additionally, 5 patients (71%) had DQ2, and 4 (57%) had both DR52 and DQ2. In female patients with chronic hepatitis C, a genetic susceptibility to autoimmune hepatitis may exist, possibly triggered by immunostimulating effects during interferon therapy. Immunosuppressive treatment has been well tolerated and seems to be effective.  相似文献   

17.
Bile duct epithelia contain an abundance of carbonic anhydrase. Antibodies to this enzyme have been described in autoimmune disorders. Serum from patients with immune-mediated liver diseases was studied to determine whether antibodies to carbonic anhydrase II and/or pyruvate dehydrogenase could distinguish autoimmune cholangitis as immunologically distinct from primary biliary cirrhosis. Antibody assays to carbonic anhydrase II (Western blot) and pyruvate dehydrogenase (flow cytometry) were performed on the sera of patients with autoimmune cholangitis (6), primary biliary cirrhosis (12), primary sclerosing cholangitis (12), autoimmune hepatitis (12), and control (Gilbert syndrome; 8). Reactivity to carbonic anhydrase II was detected in 5 of 6 patients with autoimmune cholangitis, 1 of 12 patients with primary biliary cirrhosis, 1 of 12 patients with autoimmune hepatitis, and no other patients. Individuals with autoimmune cholangitis were more likely than the other patients to be reactive to carbonic anhydrase II (P < 0.001). Patients with primary biliary cirrhosis were more reactive to pyruvate dehydrogenase compared with all other groups (P < 0.001). An antibody to human carbonic anhydrase II is frequently detected in the sera of patients with autoimmune cholangitis and is uncommon or not present in other cholangiopathies. These data provide evidence that autoimmune cholangitis and primary biliary cirrhosis represent distinct entities with unique patterns of immunoreactivity.  相似文献   

18.
A prognostic estimation formula of acute liver damage was evaluated by using clinical data and technetium-99m-diethylenetriaminepentaacetic acid-galactosyl-human serum albumin (99mTc-GSA) scintigraphy in order to determine operability for orthotopic liver transplantation (OLT). Forty-six patients hospitalized for acute liver damage were divided into survival (n = 35) and non-survival (n = 11) groups. Univariate and multivariate analyses were used to identify significant factors that affected prognosis. Logistic regression analysis was performed to predict prognosis with effective factors. Ten independent factors with significant differences were identified and further analyzed for significance by logistic regression analysis. Among the 10 factors, age and LHL15/HH15 were identified as having meaningful differences for predicting convalescence. The following formula was developed:
  相似文献   

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Recent studies have suggested that esophageal human papillomavirus infection could be a risk factor for esophageal squamous cell carcinoma. The aim of this study was to evaluate the prevalence of human papillomavirus DNA sequences in the esophagus of French patients with esophageal squamous cell carcinoma. Multiplex polymerase chain reactions with consensus primers directed to the L1 gene or specific primers for human papillomavirus types 6, 11, 16, 18, 31, and 33 directed to E6 gene (40 cycles followed by restriction mapping of the amplified products) were used to determine the presence of human papillomavirus DNA sequences in esophageal squamous cell carcinoma (n = 75), normal adjacent mucosa (n = 49), and metastatic lymphadenopathies (n = 5). As an internal control, a target located in the embryonic myosin heavy-chain gene was used in each reaction. Human papillomavirus DNA sequences could not be detected in any of the tumoral samples, the normal adjacent mucosa, or the metastatic lymphadenopathies. Human papillomavirus seems not to be implicated in esophageal carcinogenesis, at least in French patients, because the viral genomes are not associated with esophageal squamous cell carcinomas.  相似文献   

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