Altered expression of the mismatch repair genes in DF-1 cells infected with the avian leukosis virus subgroup A.

The absence or deficiency of DNA mismatch repair (MMR) activity results in microsatellite instability (MSI) in cancer. The avian leukosis virus (ALV) causes neoplastic disease in chickens. In this study, the status of MMR, MSI, the cell cycle and apoptosis were detected in DF-1 cells after avian leukosis virus subgroup A infection. Flow cytometry analysis results indicated that there was no significant difference in cell apoptosis between the control and infected groups. The percentage of cells in S and G2 phases were increased in the infected group. MSI and mutation of MSH2 and MLH1 gene exons were absent in DF-1 cells after infection. Levels of MSH2 and MLH1 mRNA were dramatically increased in DF-1 cells after infection. These results demonstrated that ALV RAV-1 infection may promote the expression of MSH2 and MLH1 genes rather than resulting in gene mutations. Mismatch repair functions were normal and may be have relationships with the arrest of S phase and G2 phase.

Microsatellite instability in chicken lymphoma induced by gallid herpesvirus 2.

Microsatellite instability (MSI) has been found in a range of human tumors, and little is known of the links between MSI and herpesvirus. In order to investigate the relationship between MSI and Gallid herpesvirus 2 (GaHV-2)-induced lymphoma, fifteen Marek's disease (MD) lymphomas were analyzed through using 46 microsatellite markers, which were amplified by PCR from DNA specimens of lymphoma and normal muscular tissues from the same chicken. PCR products were evaluated by denaturing polyacrylamide gel electrophoresis for MSI analysis. MSI was proved in all lymphomas, at least in one locus. Thirty of the 46 microsatellite markers had microsatellite alterations. These results suggested that GaHV-2-induced lymphoma in chickens is related to MSI, and this is the first report to demonstrate that MSI is associated with the GaHV-2 induced lymphoma in chicken.

Analysis of koi herpesvirus latency in wild common carp and ornamental koi in Oregon, USA.

Koi herpesvirus (KHV) infection is associated with high mortalities in both common carp (Cyprinus carpio carpio) and koi carp (Cyprinus carpio koi) worldwide. Although acute infection has been reported in both domestic and wild common carp, the status of KHV latent infection is largely unknown in wild common carp. To investigate whether KHV latency is present in wild common carp, the distribution of KHV latent infection was investigated in two geographically distinct populations of wild common carp in Oregon, as well as in koi from an Oregon-based commercial supplier. Latent KHV infection was demonstrated in white blood cells from each of these populations. Although KHV isolated from acute infections has two distinct genetic groups, Asian and European, KHV detected in wild carp has not been genetically characterized. DNA sequences from ORF 25 to 26 that are unique between Asian and European were investigated in this study. KHV from captive koi and some wild common carp were found to have ORF-25-26 sequences similar to KHV-J (Asian), while the majority of KHV DNA detected in wild common carp has similarity to KHV-U/-I (European). In addition, DNA sequences from IL-10, and TNFR were sequenced and compared with no differences found, which suggests immune suppressor genes of KHV are conserved between KHV in wild common carp and koi, and is consistent with KHV-U, -I, -J.

[Impact of techniques for gastrointestinal tract reconstruction following gastrectomy on pancreatic ß-cell function in patients with type 2 diabetes mellitus].

OBJECTIVE: To evaluate the impact of different techniques for gastrointestinal tract reconstruction on postoperative pancreatic ß-cell function in patients with type 2 diabetes mellitus (T2DM). METHODS: Twenty-three patients with gastric cancer and T2DM were studied. Techniques for reconstruction included Billroth I (n=13) and bypass procedures(Billroth II n=4 and Roux-en-Y anastomosis n=6). Pancreatic ß-cell function was evaluated by oral glucose tolerance test (OGTT). Serum insulin was measured by electrochemiluminescence immunoassay and blood glucose by glucose oxidase method. HOMA-IR and HOMA-ß were assessed. RESULTS: T2DM remission rate was 90% (9/10) in the bypass group, and 23% (3/13) in Billroth I group (P<0.01). Glycosylated hemoglobin A1c and glycated hemoglobin HbA1 were improved significantly in patients after bypass procedures(P<0.05), but the difference in Billroth I group was not statistically significant (P>0.05). OGTT showed that fasting and post-glucose load plasma glucose at each time point were significantly lower in the bypass group compared to the Billroth I group. At 30 minutes and 60 minutes after glucose load, insulin levels and insulin release index were significantly higher in the bypass group compared to Billroth I( group, as were levels of HOMA-ß and ΔI30/ΔG30 in the bypass group(P<0.05). CONCLUSION: Gastrointestinal bypass following gastrectomy may induce resolution of T2DM and improve ß-cells function.

Resveratrol attenuates renal hypertrophy in early-stage diabetes by activating AMPK.

BACKGROUND: Recent studies suggest the involvement of the adenosine monophosphate-activated serine/threonine protein kinase (AMPK) pathway in the pathogenesis of diabetic nephropathy (DN). Resveratrol, an agent that activates AMPK, may have the potential to protect against the development of DN. This study was designed to investigate the therapeutic effects of resveratrol on renal hypertrophy in early-stage diabetes and the underlying mechanisms. METHOD: Molecular and structural changes involved in the pathogenesis of DN were tested in a rat model of early-stage diabetes. Renal mesangial cells (RMCs) were cultured in media containing different concentrations of glucose with or without resveratrol. Cellular DNA synthesis was assayed by measuring (3)H-thymidine incorporation. The phosphorylation status of AMPK, eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1), and phospho- ribosomal protein S6 (S6) was analyzed by Western blot. RESULTS: Resveratrol reduced plasma creatinine and urinary albumin excretion and attenuated renal hypertrophy without affecting blood glucose levels. Moreover, resveratrol activated AMPK and inhibited phosphorylation of 4E-BP1 and S6 in diabetic rat kidneys. In vitro, resveratrol blocked high glucose-induced dephosphorylation of AMPK and phosphorylation of 4E-BP1 and S6 and strongly inhibited both the DNA synthesis and proliferation of RMCs. CONCLUSION: These findings suggest the possibility that resveratrol exerts antiproliferative, antihypertrophic effects by activating AMPK and reducing 4E-BP1 and S6 phosphorylation, thus suppressing the development and progression of DN.

Palliative gastrectomy and chemotherapy for stage IV gastric cancer.

PURPOSE: To investigate the value of palliative gastrectomy and chemotherapy in a large series of patients with stage IV gastric cancer. METHODS: A total of 389 patients were identified in survival analysis. Among which, 183 cases received palliative gastrectomy (PG) and 206 cases received unresectable operation, 184 cases received palliative chemotherapy (PC) and 205 cases did not receive chemotherapy. The survival advantages of patients, based on treatments modality, were also analyzed in patients with liver metastasis, peritoneal dissemination and lymph node metastasis. RESULTS: The 1-year, 3-year, 5-year survival rate of those patients who were treated with PG + PC were 85.7% (96/112), 32.1% (36/112), and 8.9% (10/112), which were far better than those who were not. For those patients with liver metastasis, peritoneal dissemination, and/or N3 lymph node metastasis, survival advantages were also present if treated with this multimodality approach. CONCLUSION: The survival time and palliative duration were significantly longer in patients after PG than after non-resection operations. Postoperative chemotherapy prolonged the survival time of patients after palliative surgery. PG combined with adjuvant chemotherapy may improve survival in patients with stage IV gastric cancer, even with liver metastasis, peritoneal dissemination, and lymph node metastasis.