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71.
Alphaviruses, such as chikungunya virus and Ross River virus (RRV), are associated with outbreaks of infectious rheumatic disease in humans worldwide. Using an established mouse model of disease that mimics RRV disease in humans, we showed that macrophage-derived factors are critical in the development of striated muscle and joint tissue damage. Histologic analyses of muscle and ankle joint tissues demonstrated a substantial reduction in inflammatory infiltrates in infected mice depleted of macrophages (i.e., "macrophage-depleted mice"). Levels of the proinflammatory factors tumor necrosis factor-alpha, interferon-gamma, and macrophage chemoattractant protein-1 were also dramatically reduced in tissue samples obtained from infected macrophage-depleted mice, compared with samples obtained from infected mice without macrophage depletion. These factors were also detected in the synovial fluid of patients with RRV-induced polyarthritis. Neutralization of these factors reduced the severity of disease in mice, whereas blocking nuclear factor kappaB by treatment with sulfasalazine ameliorated RRV inflammatory disease and tissue damage. To our knowledge, these findings are the first to demonstrate that macrophage-derived products play important roles in the development of arthritis and myositis triggered by alphavirus infection.  相似文献   
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BACKGROUND: Acute pancreatitis has occasionally been associated with Crohn's disease (CD), but whether a causal association exists remains unclear. We sought to determine the frequency of etiologies in a consecutive series of patients with CD with acute pancreatitis. METHODS: A centralized diagnostic index was used to identify all patients with CD with acute pancreatitis that were evaluated at Mayo Clinic Rochester between 1976 and 2001. Both diagnoses were made or confirmed at our institution. Records were abstracted for demographics, presenting symptoms, diagnostic tests, risk factors of pancreatitis, treatment, and follow-up. RESULTS: Forty-eight patients with CD with pancreatitis were identified. The median age at diagnosis of acute pancreatitis was 47 years (range, 31-91 yr). Forty-six (96%) met biochemical criteria for acute pancreatitis. The most sensitive radiographic tests were abdominal computed tomography (70%) and abdominal ultrasound (46%). The etiology of pancreatitis was considered to be gallstones (21%), significant alcohol intake (15%), use of purine analogs (13%), duodenal Crohn's involvement (12%), postendoscopic retrograde cholangiopancreatography complications (10%), postoperative complications (12%), use of other medications (4%) and idiopathic (8%). The median length of hospitalization was 7 days (range, 0-40 d). Ten patients (21%) had recurrence of acute pancreatitis. Three patients (6%) were subsequently diagnosed with pancreatic cancer. CONCLUSIONS: A definite etiology could be identified in most patients with CD with acute pancreatitis. Gallstones and alcohol accounted for more than one third of cases, whereas CD, either because of duodenal involvement or medications used for its treatment, accounted for more than one quarter of the cases. A small proportion of patients remained idiopathic.  相似文献   
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Detection of abnormally elevated levels of molecules in patients with oral cancer may be useful in early diagnosis. These markers can be included in current Histopathology grading and in TNM staging systems of Oral Squamous Cell Carcinoma (OSCC) to make it more efficient. Several pro-angiogenic molecules have been assessed for the same reason. Endothelin-1 (ET-1) is a vasoactive peptide associated with the development and spread of many solid tumors, including Squamous Cell Carcinoma (SCC), but its utility in OSCC has not been confirmed.

Objective

This study aims to evaluate the role of the serum big ET-1 as a biomarker of OSCC, by correlating it with the clinical staging and the histopathological grading.

Material and Methods

Serum levels of big ET-1 measured by the sandwich Enzyme-Linked Immunosorbent Assay (ELISA) in 40 OSCC cases were compared with the levels from the control group using independent t-test. Clinical stages and histopathological grades of OSCC cases were compared in relation to their mean levels of serum big ET-1, one using the Analysis of Variance (ANOVA) test and the other the independent t-test, respectively. The significance of the mean difference between the groups was evaluated by Tukey’s multiple comparison test. All statistical analyses were performed on GraphPad statistical software version 5.0.

Results

By comparing the mean of the big ET-1 concentrations of cases and controls, the independent t-test revealed significant higher big ET-1 concentration of OSCC cases when compared to controls (p<0.0001). Tukey’s multiple comparison test also revealed statistically significant difference among all OSCC stages in relation to the mean levels of serum big ET-1. However, the mean of the big ET-1 concentrations of cases of grade I and of grade II did not differ statistically (p=0.729).

Conclusion

Serum big ET-1 levels may be useful as a diagnostic tool in OSCC and as an adjunct to OSCC staging. However, its use as a prognostic marker warrants larger prospective studies.  相似文献   
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This study investigates a case in a type I diabetic animal model, using nonobese diabetic mice, affected with hypoglycaemia and liver necrosis with other symptomatic complications. This particular animal was markedly different from other animals in the colony, and the investigations we carried out diagnosed various conditions such as growth retardation, frank diabetes, hypoinsulinaemia, hypoglycaemia and multiple foci liver necrosis with nucleomegaly. From the differential diagnosis, we hypothesize that this abnormality might be due to carbohydrate metabolic deficiency giving rise to diabetes and liver necrosis. We postulate that in these conditions, the liver controls the pancreas and that the liver should be the key target organ to control diabetes coupled with hypoglycaemia. Further investigations into the relationship between the carbohydrate metabolism, liver failure and overt diabetes in nonobese diabetic (NOD) animal models might have relevance to human disease.  相似文献   
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