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Hepatitis C is an oncogenic virus although the mechanisms responsible for this behavior are not clear. We studied the effects of hepatitis C virus (HCV) core protein expression on Telomerase, an enzyme closely associated with cellular immortalization and neoplasia. The aim of this study was to investigate the effects of HCV core protein on the regulation of Telomerase activity in human hepatoma cells. Regulation and expression of human Telomerase reverse transcriptase (TERT) was compared in Huh7 cells stably transfected with HCV core protein or cells expressing vector alone. Telomerase activity was measured using Quantitative Telomerase Detection (QTD) and telomere length was measured by fluorescence in situ hybridization (FISH). Transient transfection and luciferase assay were used to evaluate TERT promoter activity. Telomerase activity was increased twofold in Huh7 cells expressing HCV core protein compared to controls ( P < 0.01). This was accompanied by a 1.4-fold increase of TERT mRNA and 1.9-fold increase in TERT protein ( P < 0.01 in either case). Cellular fractionation and immunocytochemical studies showed increased localization of TERT in the nucleus of core-expressing cells as compared to controls. FISH assay confirmed that telomeres of HCV core-expressing Huh7 cells were relatively longer than those of control cells (0.22 + 0.05 vs. 0.12 + 0.03, P < 0.01). TERT promoter activity was enhanced about 30% in HCV core-expressing Huh7 cells compared to control cells ( P < 0.02). HCV core protein is associated with increased Telomerase activity in hepatoma cells. These findings suggest that enhancement of Telomerase activity by HCV core protein may contribute to the oncogenicity of HCV. J. Med. Virol. 82:239-248, 2010. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

This article examines the effects of sex on managerial value systems in the U.S. It ponders over the relationship between two areas of interest and importance to organizations, similarities and differences between male and female managers, and the value systems of managers. These issues are of interest because increasing numbers of women are entering managerial ranks. Research on sex-role stereotypes suggests that "masculine" characteristics such as dominance, ambition, and independence have typically been associated with men, and "feminine" characteristics such as nurturance, sub-missiveness, and sensitivity to the needs of others with women. If similar stereotypes were to apply to managerial values, female managers could be expected, for example, to place greater importance on socially-oriented goals such as employee morale and community relations and to place less importance on production-oriented goals such as efficiency and high profits than would male managers. Consequently, if previous assertions about the impact of personal value systems were accurate, one could anticipate a gradual shift in the major concerns and decision-making orientation of organizations as more women assumed managerial positions, particularly at upper levels.

Discusses ways on how executives should manage conflicts in the workplace. Percentage of time devoted by a manager in dealing with conflict; Positive and negative outcomes of conflict; Elements in every conflict; Reasons for developing difference between conflicting parties; Five conflict handling modes.

Monoclonal or affinity-purified antibodies specific to Novikoff hepatoma cytokeratin p39 were employed to study the origin and fate of p39-containing cell types during hepatocarcinogenesis induced with N,N-dimethyl-p(m-tolylazo)aniline. Frozen sections were obtained from the livers of animals autopsied temporally during carcinogen feeding and were assayed immunohistochemically. In normal, untreated liver or in liver from animals fed the hepatotoxin alpha-naphthylisothiocyanate, the localization of p39 was restricted to bile duct epithelial cells while hepatocytes were non-reactive. However, during carcinogen treatment we observed a sequential appearance of immunoreactive cells which were similar morphologically to the classical ‘oval’ cells of hepatocarcinogenesis; eventually these cell types were enriched around the preneoplastic hepatocyte nodules. Occasional transformed hepatocytes within the nodules exhibited strong immunoreactivity. In the later stages of hepatocarcinogenesis, these antibodies stained the epithelial cells in areas of severe adenosis as well as the neoplastic epithelial cells of cholangiomas and some, but not all, hepatocellular carcinomas. Our results document the presence of p39 in the ‘oval’ cells of hepatocarcinogenesis and indicate that some populations of transformed hepatocytes exhibit this cytokeratin after transformation. [ABSTRACT FROM PUBLISHER]

Chromosomal proteins from rat liver have been assessed immunologically for changes in specific cytokeratins or primary tumor nonhistone proteins during treatment with an azo dye hepatocarcinogen (3′-methyl-4-dimethylaminoazobenzene), (3′-Me-DAB) or the hepatotoxin a-naphthyl-iso-thiocyanate (α-NIT). Fisher rats were fed laboratory diets supplemented with either agent and sacrificed sequentially at various intervals. Chromosomal proteins from these livers were electro-phoresed in the presence of sodium dodecyl sulfate, transferred to nitrocellulose sheets and reacted with rabbit antisera to Novikoff hepatoma cytokeratin or 3′-Me-DAB induced primary hepatoma dehistonized chroma tin. Livers from carcinogen-fed animals exhibited distinct, sequential changes in antigenic nonhistone proteins until the immunological specificity characteristic of the hepatoma was achieved concomitant with the induction of neoplasia. No antigenic changes were observed to occur in hepatotoxin-fed animals. The rat carcinoma-specific cytokeratin antigens p39 and p49 in Novikoff hepatoma were observed to appear as early as three weeks after the start of carcinogen feeding and were present maximally in 23 week livers with carcinoma. These cytokeratins were not detected in α-NIT-fed animals. Our results support the concept that the carcinogenic process can be related to temporal changes in the expression of cell-specific cytokeratins in addition to nonhistone chromosomal proteins. Furthermore, these data suggest the expression of these antigenic species to not be the direct result of changes in liver structure and cellular composition associated with carcinogen toxicity; rather, neoplastic transformation is apparently required. [ABSTRACT FROM PUBLISHER]

Details the critical stages in the growth of a corporation. Gaining of stability; Gaining of reputation; Development of pride; Achievement of uniqueness and adaptability; Contribution to society.

The techniques described in this article would transform observers attending a presentation on group dynamics into learning participants. The resistances of the audience to learning about self-and in public-are met with nine strategies or "Guidelines for Audience Involvement" devised by the behavioral scientist authors. In the language of the legitimate stage, observers fill participant roles under a competent director who bars the critics and utilizes a good script and a large cast. [ABSTRACT FROM PUBLISHER]

This article describes the way in which one university, the University of California, undertook a program of education for the two major political parties and established an on-going relationship with them. This program aims to deal to with political issues and political processes during the coming presidential election year. The chairmen of the Democratic and Republican State Central Committees were asked to nominate leaders to discuss a possible educational program with political party leaders and workers. Interviews were conducted with leaders from both parties were interviewed. Factors that facilitated the development of the activities, reduced resistance and helped to develop effective working relationships among the three organizations are discussed.

This article poses some questions and gives some reflections of four participants in the training programs designed to maximize the utilization of the experiences of the leaders in conjunction with the specialized skills of the social scientist. It addresses the issue of whether this method can contribute to the education of political leaders, what modifications of training theory and practice have been necessary. and what has been the overall effect of the training programs for political leaders. It discusses the major obstacles to the application of social science to practical politics and identifies research or other inquiry needed to further the improve the programs.