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We studied the correlation between dexamethasone (Dex) induced growth effects and modulation of epidermal growth factor receptor (EGFR) expression in OVCA 433 ovarian cancer cells. These cells express specific high and low affinity 125I-EGF binding sites and are growth stimulated by EGF. Dex exhibits mitoinhibitory effects by recruiting OVCA 433 cells in the G0-G1 phase of the cycle, but increases the number of both the high and the low affinity EGFR in a dose dependent manner. The maximal EGFR expression increase occurs after 24 h of Dex treatment consistently with Northern blot studies. The mitogenic activity of EGF in OVCA 433 cells is not affected by the presence of Dex. Moreover Dex growth inhibition occurs in JA1 cells, an ovarian cancer cell line which expresses unfunctional EGFR and which is unresponsive to EGF. Our results indicate that the Dex induced growth effects occur independently of EGFR expression.  相似文献   
23.
We have previously described the isolation of primitive, slow-proliferating progenitors from normal, circulating CD34+ cells by using the fluorescent dye 5-6-carboxyfluorescein diacetate succinimidyl ester (CFDA-SE). CFDA-SE(bright) (primitive) and CFDA-SE(dim) (differentiating) cells were isolated following cytokine stimulation on the basis of their different proliferation rates. In the present work we analysed the expression levels of a number of proteins involved with differentiation, proliferation and survival/apoptosis in CFDA-SE(bright)/CD34+/slow-proliferating cells that were previously defined as progenitors capable of differentiating into different lineages. The aim of this work was to gain a better understanding of our model system in order to define some of the important parameters that regulate differentiation in haematopoietic progenitors. GATA-1 and PU.1 RNA levels were similar in freshly isolated (d 0) CD34+ and in CFDA-SE(bright) (bright) cells, whereas they increased in CFDA-SE(dim) (dim) cells. Accordingly, Nm23 was expressed at higher levels in bright cells. Moreover, bright cells had higher p21WAF1/CIP1, p27KIP1 and p16Ink4 protein levels than dim cells. Consistently, Cdc2 and Cdk2 kinase activity was much higher in the dim than in the slower proliferating bright cells. C-myc and p53 levels were higher in bright cells than in d 0 CD34+ and dim cells, and so was Bcl-xL, which followed the trend we have previously described for Bcl-2. Thus, bright cells, despite having a higher proliferation rate than the starting d 0 CD34+ population, have strikingly elevated levels of cyclin-dependent kinase inhibitors, which are likely to also act as inhibitors of differentiation.  相似文献   
24.
Analyzing the evolutionary pattern of the influenza A(H1N1)pdm09 strain in different regions is important for understanding its diversification. We therefore conducted this study to elucidate the genetic variability and molecular evolution of the influenza A(H1N1)pdm09 strains that circulated during the 2009–2010 and 2010–2011 influenza seasons in Sendai, Japan. Nasopharyngeal swab specimens were collected from patients with influenza-like illnesses who visited outpatient clinics in Sendai City, Japan, from September 2009 to April 2011. A total of 75 isolates were selected from September 2009 to April 2011 to analyze the genetic changes in the entire hemagglutinin 1 (HA1) segment of the HA gene and the neuraminidase (NA) gene based on sequence analysis. Bayesian coalescent Markov chain Monte Carlo analyses of HA1 and NA gene sequences were performed for further analysis. High sequence identities were observed for HA1 and NA in influenza A(H1N1)pdm09, displaying 99.06 and 99.33 % nucleotide identities, respectively, with the A(H1N1)pdm09 vaccine strain A/California/07/2009. The substitution rates of nucleotides for HA1 in the 2009–2010 and 2010–2011 were 1.5 × 10?3 and 1.6 × 10?3 substitutions per site per year, respectively. Phylogenetic tree analysis demonstrated that Sendai isolates were clustered into global clade 7, which is characterized by an S203T mutation in the HA1 gene. Moreover, two distinct circulation clusters were present in the 2010–2011 season. Mutations were present in antigenic or receptor-binding domains of the HA1 segment, including A141V, S143G, S183P, S185T, and S203T. The Bayesian skyline plot model illustrated a steady rate for the maintenance of genetic diversity, followed by a slight increase in the later part of the 2010–2011 season. Selection analysis revealed that the HA1 (position 197) and NA (position 46) sites were under positive selection; however, no known mutation conferring resistance to NA inhibitors such as H275Y was observed. The effect on control of the influenza A(H1N1)pdm09 virus, including vaccine strain selection, requires continuous monitoring of the strain by genetic surveillance.  相似文献   
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The A, B, C and DR locus specificities of the human leukocyte antigens system (HLA) were determined in 45 delta-positive and 44 delta-negative Italian patients, all with HBsAg-positive chronic active liver disease; controls were 526 healthy Italian blood donors matched for age, sex and geographical origin. HLA-A, B, C gene frequencies were not significantly changed. In delta-positive patients, the frequencies of the DR locus specificities were: DR2, 37.8%; DR3, 20%; DR4, 11.1%. In the delta-negative patients, the frequencies were: DR2, 13.6%; DR3, 36.4%; DR4, 0%. Control frequencies were: DR2, 19.4%; DR3, 17.1%; DR4, 18.5%. The corrected p values of the differences between controls and delta-positive patients were: DR2, pc = 0.046; DR3, pc = NS (not significant); DR4, pc = NS. The corrected p values of the differences between controls and delta-negative patients were: DR2, pc = NS; DR3, pc = 0.03; DR4, pc = 0.002. These findings show that: (a) DR3, a genetic marker of autoimmunity, might assist the establishment of chronic HBsAg liver disease in the absence of delta superinfection; (b) DR2 is linked with failure to clear the delta agent, and (c) DR4 may protect from virus B persistence. Identification of adventitious factors such as delta may help uncover a subgroup of HBsAg carriers who are genetically predisposed to develop chronic liver disease.  相似文献   
27.
Hepatitis C virus (HCV) vaccines may be able to increase viral clearance in combination with antiviral therapy. We analysed viral dynamics and HCV‐specific immune response during retreatment for experienced patients in a phase Ib study with E1E2MF59 vaccine. Seventy‐eight genotype 1a/1b patients [relapsers (30), partial responders (16) and nonresponders (32) to interferon‐(IFN)/ribavirin‐(RBV)] were randomly assigned to vaccine (V:23), Peg‐IFNα2a‐180‐ug/qw and ribavirin 1000–1200‐mg/qd for 48 weeks (P/R:25), or their combination (P/R + V:30). Vaccine (100 μg/0.5 mL) was administered intramuscularly at week 0‐4‐8‐12‐24‐28‐32‐36. Neutralizing of binding (NOB) antibodies and lymphocyte proliferation assay (LPA) for E1E2‐specific‐CD4 + T cells were performed at week 0‐12‐16‐48. Viral kinetics were analysed up to week 16. The vaccine was safe, and a sustained virological response (SVR) was achieved in 4 P/R + V and 2 P/R patients. Higher SVR rates were observed in prior relapsers (P/R + V = 27.3%; P/R = 12.5%). Higher NOB titres and LPA indexes were found at week 12 and 16 in P/R + V as compared to P/R patients (P = 0.023 and 0.025, P = 0.019 and <0.001, respectively). Among the 22 patients with the strongest direct antiviral effects of IFN (ε ≥ 0.800), those treated with P/R + V (10) reached lower HCV‐RNA levels (P = 0.026) at week 16. HCV E1E2MF59 vaccine in combination with Peg‐IFNα2a + RBV was safe and elicited E1E2 neutralizing antibodies and specific CD4 + T cell proliferation. Upon early response to IFN, vaccinations were associated with an enhanced second phase viral load decline. These results prompt phase II trials in combination with new antiviral therapies.  相似文献   
28.
We report the identification of a mutation in the solute carrier family 5 member 2 (SLC5A2) gene, which encodes sodium–glucose cotransporter 2, in a family with familial renal glucosuria. The proband was a 26‐year‐old Japanese man referred to the diabetes division with repeated glucosuria without hyperglycemia. His mother, uncle and grandfather also had a history of glucosuria. A heterozygous missense mutation (c.303T>A:p.N101K) in SLC5A2 was identified in the patient and his mother, but not in 200 chromosomes from 100 healthy and unrelated individuals, or in 3,408 Japanese individuals in the Tohoku Medical Megabank. Furthermore, bioinformatics software predicted that this lesion would be pathogenic. We infer that the mutation led to clinically relevant sodium–glucose cotransporter 2 dysfunction. The patient showed no symptoms of hypoglycemia, but continuous glucose monitoring confirmed asymptomatic hypoglycemia.  相似文献   
29.
Single nucleotide polymorphisms (SNPs) near the interleukin 28B (IL28B) region are the strongest baseline predictors of a sustained virologic response (SVR) to peg-interferon (PegIFN) and ribavirin (Rbv) in patients with hepatitis C virus (HCV) genotype 1 infection. Whether this holds true for HCV-4 patients too is unknown. The aim was to investigate the predictive power of the rs12979860 IL28B SNP for a response to Peg-IFN and Rbv in HCV-4 patients. All HCV-4 patients consecutively treated between September 2004 and June 2010 with PegIFN and Rbv at two liver centers at the Maggiore Hospital Milan (Italy) underwent TaqMan SNP Genotyping assays for testing rs12979860 genotype. Of 112 treated patients (98 males, 75 of Egyptian descent, 26 with cirrhosis) 103 were included in the final analysis; five discontinued treatment for nonvirologic reasons and four did not consent to genetic testing. Twenty-four (23%) were genotype CC, 65 (63%) CT, and 14 (14%) TT. Overall, 50 (49%) achieved an SVR: 21 (88%) CC patients versus 29 (37%) CT/TT (P < 0.0001). CC patients more often had a rapid virologic response (RVR) than CT/TT patients (12, 50% versus 23, 29%; P = 0.08), while also showing lower relapse rates (0% [0/21] versus 36% [16/45] P = 0.0013). In non-RVR patients, SVR rates were higher in CC than CT/TT patients (9 [75%] versus 13 [23%] P = 0.001). By logistic regression, the IL28B rs12979860 CC genotype was an independent predictor of SVR with an odds ratio of 8.0 (95% confidence interval 2.00-32.01; P = 0.003). CONCLUSION: The IL28B rs12979860 SNP may have an added value in the treatment algorithm of HCV-4 patients because it is the strongest predictor of an SVR to PegIFN/Rbv therapy.  相似文献   
30.
Standard of care for patients with chronic hepatitis C is pegylated interferon (pegIFN) combined with ribavirin (Rbv). It results in persistent viral eradication and prevents the progression of liver disease and the associated complications in about 50% of treated patients. Currently, two PegIFNs are available that differ significantly in terms of pharmacokinetic and pharmacodynamic profiles as a consequence of different pegylation chemistries. While the registration trials of the two therapeutic regimens demonstrated the superiority of each PegIFN vs the native IFN α2b, the superiority of one regimen over the other in terms of treatment efficacy remains unknown. Retrospective cohort studies and randomized prospective head-to-head trials have attempted to resolve the considerable controversy over this issue and support evidence-based treatment decisions.  相似文献   
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