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91.

Purpose

Recent evidence has shown that altered patterns of microRNA (miRNA) expression correlate with various human cancers. We investigated the clinical significance of miR-10b and its involvement in chemotherapeutic resistance to 5-fluorouracil (5-FU), which is a key component of common chemotherapy regimens in colorectal cancer.

Methods

Quantitative RT-PCR was used to evaluate the clinicopathologic significance of miR-10b expression in 88 colorectal cancer cases. We also investigated the chemotherapeutic sensitivity to 5-FU in miR-10b-overexpressing colorectal cancer cells. To explore the mechanism of chemoresistance in miR-10b transfected cells, we examined whether miR-10b inhibits the pro-apoptotic BH3-only Bcl-2 family member BIM(BCL2L11), a key mediator of chemotherapy-induced cell death.

Results

High level miR-10b expression was found to be significantly associated with high incidence of lymphatic invasion (P?=?0.0257) and poor prognosis (P?=?0.0057). Multivariate analysis indicated that high miR-10b expression is an independent prognostic factor for survival. In vitro studies revealed that miR-10b directly inhibits pro-apoptotic BIM, and the overexpression of miR-10b confers chemoresistance in colorectal cancer cells to 5-FU.

Conclusions

MiR-10b is a novel prognostic marker in colorectal cancer. Moreover, the expression of miR-10b is a potential indicator of chemosensitivity to the common 5-FU-based chemotherapy regimen.  相似文献   
92.

Background  

Intrahepatic cholangiocarcinoma (ICC) is categorized as peripheral ICC (PICC) or hilar ICC (HICC). The aims of this study are to clarify clinicopathological differences between PICC and HICC and to determine useful prognostic factors for patients with ICC following aggressive surgical resection.  相似文献   
93.
BACKGROUND: Mesangial cell proliferation and phenotypic alteration occur in an early phase of glomerular injury and precede increased extracellular matrix accumulation. A critical growth factor responsible for mesangial proliferation is platelet-derived growth factor (PDGF), which has proved to be a potent mitogen. METHODS: We generated a chimeric cDNA encoding an extracellular domain of the beta-PDGF receptor fused with IgG-Fc, termed PDGFR/Fc, and examined the feasibility of gene therapy targeting PDGF using PDGFR/Fc. RESULTS: Chimeric PDGFR/Fc molecule completely inhibited the tyrosine phosphorylation of beta-PDGF receptors and cellular proliferation induced by PDGF in vitro. We then introduced the PDGFR/Fc expression vector into the muscle of anti-Thy-1 model of glomerulonephritic rats by electroporation. The plasma concentration of chimeric PDGFR/Fc levels was 244.4 +/- 89.8 ng/mL four days after transfection. On day 5, PDGFR/Fc gene transfer significantly reduced the number of PCNA-positive cells and glomerular cell numbers by 59.6 and 23.2%, respectively. Northern blot analysis demonstrated that glomerular mRNA levels of alpha-smooth muscle action, transforming growth factor-beta 1, and type I collagen were also suppressed on days 5 and 7 by the PDGFR/Fc transfection. There was a significant reduction in the matrix score of the transfected nephritic rats (2.91 +/- 0.75 and 2.06 +/- 0.95; disease control group vs. treated group, P < 0.001). CONCLUSION: These results suggest that gene therapy by the manipulation of PDGF action using electroporation-mediated PDGFR/Fc gene transfer to the skeletal muscle might be a useful treatment for mesangioproliferative glomerulonephritis.  相似文献   
94.
This is a case report of the successful surgical treatment of acute dissecting aneurysm of the ascending aorta. The patient was a 65-year-old female, who admitted to the hospital 3 hours after the onset of severe back pain. Enhanced CT of the chest and abdomen revealed acute dissection of the ascending aorta from its origin to the bilateral common iliac arteries. Thirteen hours initiation of the symptoms, operation was carried out using pump-oxygenator with hypothermia. Transverse incision of the ascending aorta revealed acute dissection in anterior aspect extending to two third of the circumference. The proximal small intimal tear was found 3 mm apart from the right coronary artery ostium. Upon closure of the tear resulting in obliteration of the right coronary artery, it required bypass procedure between the right coronary artery and the innominate artery using the saphenous vein graft. The aortic incision was directly closed using Dacron felt bolsters. Postoperative studies revealed disappearance of the proximal aortic dissection, patency of the bypass graft and existence of distal aortic dissection. Patient is in active life 6 months after operation.  相似文献   
95.
B-cell lymphoma associated with haemophagocytic syndrome (HPS) is extremely rare in Western countries but has recently been increasingly reported in Asian countries. We describe seven patients with B-cell lymphoma associated with HPS, six males and one female, age range 41-82 years (median 63 years). All patients had fever and splenomegaly, and six of the seven patients had hepatomegaly with no associated lymphadenopathy. The bone marrow showed haemophagocytosis and an infiltration of lymphoma cells. All patients showed increased levels of lactate dehydrogenase, C-reactive protein, ferritin and soluble interleukin-2 receptor. Lymphoma cells were positive for CD19. CD20 and surface immunoglobulin in all patients examined, and positive for CD5 in four of seven patients. Cytogenetic analyses of bone marrow cells showed a complex structural abnormality including chromosome 14q32 in two patients, 19q13 in three patients and deletion of the terminal part of 8p21 in six patients. The prognosis was poor; only two of the seven patients have survived in complete remission with a median survival of 11 months. These data suggested that B-cell lymphoma associated with HPS might constitute a distinct biological and clinical disease entity. Abnormality of chromosome 19q13 and loss of 8p21 might be involved in the pathogenesis of this disease.  相似文献   
96.
Metastatic involvement of the musculoskeletal system is one of the most significant clinical issues facing orthopaedic oncologists. The number of patients with metastasis to the skeletal system from a carcinoma is 15 times greater than the number of patients with primary bone tumours of all types. However, progression patterns like disseminated carcinomatosis of bone marrow are comparatively rare. The pathophysiology for disseminated carcinomatosis of bone marrow, with a prognosis reported to be very poor, is still unknown. We describe a patient who had no symptoms with hyperphosphatasia. Bone scintigraphy showed a so-called super bone scan and a needle biopsy from the ileum showed adenocarcinoma cells. Additional endoscopic investigation was performed and signet cell gastric cancer was found. From the bone scan and biopsy, we established the diagnosis of disseminated carcinomatosis of the bone marrow. From the experience of this case, we believe that intensive stomach investigation should be considered in cases with hyperphosphatasia, even when the patient has no symptoms.  相似文献   
97.
We report a case of pulmonary arteriovenous fistula with multiple hepatic arterioportal shunts. A 23-year-old man was admitted for evaluation of a nodular shadow in the right lower lung field. Chest CT showed a homogeneous and well-defined nodular shadow in the right S7. 3-dimensional CT revealed an arteriovenous fistula composed of a feeding artery and a draining vein in the right S7. Abdominal enhanced CT revealed a diffusely heterogeneous pattern in the liver parenchyma and the portal vein staining diffusely at the late arterial phase. We diagnosed pulmonary arteriovenous fistula associated with multiple hepatic arterioportal shunts. Pulmonary arteriovenous fistula is often associated with hereditary hemorrhagic telangiectasia (HHT). This case did not meet the criteria for HHT at this time. However, we could not exclude the possibility of HHT because clinical manifestations of HHT become apparent after 40 years old among 10% of patients. The natural history and treatment of HHT are not clear. We concluded that we should be careful to detect possible manifestations as HHT when we diagnose and follow up patients with pulmonary arteriovenous fistula.  相似文献   
98.
Brain natriuretic peptide (BNP) is a powerful neurohormonal marker of left ventricular function and prognosis. Amiodarone either has no effect or improves the haemodynamics in patients with left ventricular dysfunction, but its effect on BNP is unknown. This study evaluated the effect of amiodarone on plasma BNP level in patients with heart failure and ventricular tachyarrhythmia.Plasma BNP level was studied in 46 patients with heart failure ventricular tachyarrhythmia, before (baseline) and at week 2 and months 1, 3 and 6 of amiodarone treatment. In addition, 21 patients with heart failure and ventricular tachyarrhythmia, who received an implantable cardioverter defibrillator, but not amiodarone, were studied on the same schedule. All patients had previously received potent vasodilator and beta-blocker therapy. Echocardiography and Holter monitoring were also performed.Amiodarone significantly decreased plasma BNP levels at week 2 to month 6 during therapy. Heart rates and frequencies of premature ventricular complexes were markedly reduced by amiodarone. Echocardiographic findings did not show a change in left ventricular end-diastolic dimensions, despite a slight increase in fraction shortening at month 6 during amiodarone therapy. The above parameters showed no change in patients without amiodarone. The effect of heart rate, premature ventricular complexes, fraction shortening, serum creatinine or thyroid stimulating hormone level was not significantly associated with decrease in BNP level during amiodarone therapy by a multivariate analysis. Among amiodarone-treated patients, mortality was higher in 24 with BNP levels 100 pg/ml at month 6 than in 22 with BNP levels <100 pg/ml during a mean follow-up period of 31 months.Amiodarone appears to have a decreasing effect on plasma BNP level, as well as an antiarrhythmic effect, in patients with heart failure and ventricular tachyarrhythmia.  相似文献   
99.
Prognostic factors for chronic active Epstein-Barr virus infection   总被引:11,自引:0,他引:11  
Chronic active Epstein-Barr virus infection (CAEBV) is a high-mortality and high-morbidity disease. To clarify the prognostic factors, a national survey was performed in Japan, and data for 82 patients who met the criteria for CAEBV were analyzed. Of these 82 patients, 47 were alive and 35 had already died. Multivariate analysis revealed that thromobocytopenia and age at disease onset were correlated with mortality. The probability of 5-year survival was 0.45 for older patients (onset age, > or = 8 years), 0.94 for younger patients (P<.001), 0.38 for patients with thrombocytopenia (platelet count < 12 x 10(4) platelets/microL at diagnosis), and 0.76 for patients without thrombocytopenia (P=.01). Furthermore, patients with T cell infection by EBV had shorter survival times than patients with natural killer cell infection (probability of 5-year survival, 0.59 vs. 0.87; P<.009). Patients with CAEBV with late onset of disease, thrombocytopenia, and T cell infection had significantly poorer outcomes.  相似文献   
100.
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