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991.
Background and Objectives  Dickkopf-1 (DKK1) is the inhibitor of the canonical Wnt signaling pathway, however it is highly transactivated in various cancers, suggesting the presence of unknown mechanism. Its implication in human esophageal squamous cell carcinoma (ESCC) has not been sufficiently investigated. Patients and Methods  We evaluated DKK1 protein expression in resected specimens from 170 patients with ESCC by immunohistochemistry. Tumors were categorized as positive or negative for DKK1. The relationships between DKK1 expression in ESCC and various clinicopathological parameters and prognosis (disease-free survival; DFS) were analyzed separately. Results  Immunohistochemically, 72 (42.4%) tumors were DKK1 positive while no significant staining was observed in the normal squamous epithelium except for few basal cells. There was no significant relationship between DKK1 expression in ESCC and any of the clinicopathological parameters tested in this study. Patients with DKK1-positive tumors had poorer DFS than those with negative ESCC (5-year DFS; 31.5% versus 53.6%, P = 0.0062). Univariate analysis showed a significant relationship between pT [hazard ratio (HR) = 2.944, 95% confidence interval (CI) = 1.713–5.059, P < 0.0001], number of pN (HR = 2.836, 95% CI = 1.866–4.309, P < 0.0001), lymphatic invasion (HR = 2.892, 95% CI = 1.336–6.262, P = 0.0070), and DKK1 expression (HR = 1.763, 95% CI = 1.167–2.663, P = 0.0071) and DFS. Multivariate analysis including the above four parameters identified pT (HR = 2.053, 95% CI = 1.157–3.645, P = 0.0140), pN number (HR = 2.107, 95% CI = 1.362–3.260, P = 0.0008), and DKK1 expression (HR = 1.813, 95% CI = 1.195–2.751, P = 0.0052) as independent and significant prognostic factors for DFS. Conclusion  Our data suggest the usefulness of DKK1 as a novel predictor of poor prognosis of patients with ESCC after curative resection and also as a therapeutic target for future tailored therapies against ESCC.  相似文献   
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AIM To investigate the effects of ursodeoxycholic acid (UDCA) on chenodeoxycholic acid (CDCA)-induced liver injury in hamsters, and to elucidate a correlation between liver injury and bile acid profiles in the liver.METHODS Liver injury was induced in hamsters by administration of 0.5% (w/w) CDCA in their feed for 7 d.UDCA (50 mg/kg and 150 mg/kg) was administered for the last 3 d of the experiment.RESULTS At the end of the experiment, serum alanine aminotransferase (ALT) increased more than 10 times and the presence of liver injury was confirmed histologically. Marked increase in bile acids was observed in the liver. The amount of total bile acids increased approximately three-fold and was accompanied by the increase in hydrophobic bile acids, CDCA and lithocholic acid (LCA). UDCA (50 mg/kg and 150 mg/kg) improved liver histology, with a significant decrease (679.3 ±77.5 U/L vs 333.6 ± 50.4 U/L and 254.3 ± 35.5 U/L, respectively, P < 0.01) in serum ALT level. UDCA decreased the concentrations of the hydrophobic bile acids, and as a result, a decrease in the total bile acid level in the liver was achieved.CONCLUSION The results show that UDCA improves oral CDCA-induced liver damage in hamsters. The protective effects of UDCA appear to result from a decrease in the concentration of hydrophobic bile acids, CDCA and LCA, which accumulate and show the cytotoxicity in the liver.  相似文献   
995.
Basaloid squamous cell carcinoma (BSC) of the esophagus is a rare malignant disease. We report here a patient with recurrent esophageal BSC, who was successfully treated by systemic chemotherapy containing 5-fluorouracil (5-FU) and cisplatin (CDDP). A 57-year-old woman was diagnosed as having SCluamous cell carcinoma of the esophagus upon endoscopic examination. Curative esophagectomy with lymph node dissection was performed under the thoracoscope. The pathological diagnosis of the surgical specimen was BSC. Five months after operation, the patient was diagnosed as having a recurrence of the BSC with metastases to the liver and spleen, and a right paraclavicular lymph node. She was given systemic chemotherapy consisting of continuous infusion of 800 mg/d of 5-FU and 3 h infusion of 20 mg/d of CDDP for 5 consecutive days every 4 wk. The metastatic lesions in the spleen and right paraclavicular lymph node disappeared, and the liver metastasis was apparently reduced in size after 2 courses of chemotherapy. The tumor regression was seen over 6 courses, with progression afterwards. Although subsequent treatment with CPT-11 and CDDP was not effective, docetaxel and vinorelbine temporarily controlled the tumor growth for 2 mo. 5-FU and CDDP combination may be useful for the patients with advanced BSC.  相似文献   
996.
This report presents a case of hemorrhagic shock and encephalopathy syndrome. In the acute stage, brain magnetic resonance imaging demonstrated symmetrical hyperintensity on diffusion-weighted images and hypointensity on the apparent diffusion coefficient maps in the subcortical white matter. Whereas the abnormal diffusion-weighted imaging signals of the white matter resolved in the subacute stage, the adjacent gray matter became hyperintense on diffusion-weighted images and hypointense on apparent diffusion coefficient maps. The evolution of diffusion-weighted imaging signals is thus considered to be one of the early findings in hemorrhagic shock and encephalopathy syndrome.  相似文献   
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Diffuse alveolar damage is the histopathologic hallmark of acute respiratory distress syndrome (ARDS). A significant proportion of ARDS survivors have residual pulmonary fibrosis and compromised pulmonary function. On the other hand, heat shock protein 47 (HSP47) is a collagen-binding stress protein that is assumed to act as a collagen-specific molecular chaperone during the biosynthesis and secretion of procollagen in living cells. The synthesis of HSP47 has been reported to correlate with that of collagen in several cell lines. We examined the expression of HSP47 mRNA and protein during the progression of lipopolysaccharide (LPS)-induced ARDS in rat lung. Male Wistar rats were randomly divided into two groups: a control group with instillation of 0.9% NaCl solution alone, and a LPS group with instillation of LPS dissolved in 0.9% NaCl solution (10 mg/kg). Histologic changes thereafter appeared in the LPS-treated rats. Northern blot analysis revealed the expression of HSP47 mRNA to be markedly induced during the progression of lung damage in parallel with type I and type III collagen mRNA. These results suggest that the upregulation of HSP47 and collagen may play an important role in the fibrotic process of LPS-induced ARDS lung.  相似文献   
1000.
Ogino S  Kawasaki T  Kirkner GJ  Suemoto Y  Meyerhardt JA  Fuchs CS 《Gut》2007,56(11):1564-1571

Background

The CpG island methylator phenotype (CIMP or CIMP‐high) with widespread promoter methylation is a distinct epigenetic phenotype in colorectal cancer. In contrast, a phenotype with less widespread promoter methylation (CIMP‐low) has not been well characterised. O‐6‐methylguanine‐DNA methyltransferase (MGMT) promoter methylation and silencing have been associated with G>A mutations and microsatellite instability‐low (MSI‐low).

Aim

To examine molecular correlates with MGMT methylation/silencing in colorectal cancer.

Methods

Utilising MethyLight technology, we quantified DNA methylation in MGMT and eight other markers (a CIMP‐diagnostic panel; CACNA1G, CDKN2A (p16), CRABP1, IGF2, MLH1, NEUROG1, RUNX3 and SOCS1) in 920 population‐based colorectal cancers.

Results

Tumours with both MGMT methylation and loss were correlated positively with MSI‐low (p = 0.02), CIMP‐high (⩾6/8 methylated CIMP markers, p = 0.005), CIMP‐low (1/8–5/8 methylated CIMP markers, p = 0.002, compared to CIMP‐0 with 0/8 methylated markers), KRAS G>A mutation (p = 0.02), and inversely with 18q loss of heterozygosity (p = 0.0002). Tumours were classified into nine MSI/CIMP subtypes. Among the CIMP‐low group, tumours with both MGMT methylation and loss were far more frequent in MSI‐low tumours (67%, 12/18) than MSI‐high tumours (5.6%, 1/18; p = 0.0003) and microsatellite stable (MSS) tumours (33%, 52/160; p = 0.008). However, no such relationship was observed among the CIMP‐high or CIMP‐0 groups.

Conclusion

The relationship between MGMT methylation/silencing and MSI‐low is limited to only CIMP‐low tumours, supporting the suggestion that CIMP‐low in colorectal cancer may be a different molecular phenotype from CIMP‐high and CIMP‐0. Our data support a molecular difference between MSI‐low and MSS in colorectal cancer, and a possible link between CIMP‐low, MSI‐low, MGMT methylation/loss and KRAS mutation.  相似文献   
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