Inducible viral receptor, A possible concept to induce viral protection in primitive immune animals

A pseudolysogen (PL) is derived from the lysogenic Vibrio harveyi (VH) which is infected with the VHS1 (Vibrio harveyi Siphoviridae-like 1) bacteriophage. The lysogenic Vibrio harveyi undergoes an unequivalent division of the extra-chromosomal VHS1 phage genome and its VH host chromosome and produces a true lysogen (TL) and pseudolysogen (PL). The PL is tolerant to super-infection of VHS1, as is of the true lysogen (TL), but the PL does not contain the VHS1 phage genome while the TL does. However, the PL can become susceptible to VHS1 phage infection if the physiological state of the PL is changed. It is postulated that this is due to a phage receptor molecule which can be inducible to an on-and-off regulation influence by an alternating condition of the bacterial host cell. This characteristic of the PL leads to speculate that this phenomenon can also occur in high organisms with low immunity such as shrimp. This article proposes a hypothesis that the viral receptor molecule on the target cell can play a crucial role in which the invertebrate aquaculture animals can become tolerant to viral infection. A possible mechanism may be that the target cell disrupts the viral receptor molecule to prevent super infection. This concept can explain a mechanism for the prevention of viral infection in invertebrate animals which do not have acquired immunity in response to pathogens. It can guide us to develop a mechanism of immunity to viral infection in low-evolved-immune animals. Also, it can be an additional mechanism that exists in high immune organism, as in human for the prevention of viral infectio

Corporate social responsibility: an empirical investigation of U.S. organizations

Organizations that believe they should give something back to the society have embraced the concept of corporate social responsibility (CSR). Although the theoretical underpinnings of CSR have been frequently debated, empirical studies often involve only limited aspects, implying that theory may not be congruent with actual practices and may impede understanding and further development of CSR. The authors investigate actual CSR practices related to five different stakeholder groups, develop an instrument to measure those CSR practices, and apply it to a survey of 401 U.S. organizations. Four different clusters of organizations emerge, depending on the CSR practice focus. The distinctive features of each cluster relate to organizational demographics, perceived influence of stakeholders, managers perceptions of the influence of CSR on performance, and organizational performance

Financial and corporate social performance in the UK listed firms: the relevance of non-linearity and lag effects

Using environmental, social and governance scores compiled by Reuters Datastream for each company’s corporate social performance (CSP), we examine the relationship between CSP and corporate financial performance (CFP) of 314 UK listed companies over the period 2002–2015. We further evaluate the relationship between prior and subsequent CFP and prior and subsequent CSP. Based on the system-GMM estimation method, we provide direct evidence that suggests that while CFP and CSP can be linked linearly; however, when we examine the impact of CSP on CFP, the association is more non-linear (cubic) than linear. Our results suggest that firms periodically adjust their level of commitment to society, in order to meet their target CSP. The primary contributions of this paper are testing (1) the non-monotonous relationship between CSP and CFP, (2) the lagged relationship between the two and the optimality of CSP levels, and (3) the presence of a virtuous circle. Our results further suggest that CSP contributes to CFP better during post-crisis years. Our findings are robust to year-on-year changes in CFP and CSP, financial versus non-financial firms, and the intensity of corporate social responsibility (CSR) engagement across industries

Environmental Perception, Organizational Design and Organizational Performance: A Comparative Study

Peter A. Stanwick is an Assistant Professor of Management at Auburn University. Larry P. Pleshko is an Assistant Professor of Marketing in the Andreas School of Business at Barry University

HIV-1 replication is controlled at the level of T cell activation and proviral integration.

During progression of the Acquired Immune Deficiency Syndrome (AIDS), the human immunodeficiency virus type 1 (HIV-1) is harbored in CD4+ T cells, which act as the primary reservoir for the virus. In vitro, HIV-1 requires activated T cells for a productive infection; however, in vivo, the number of circulating T cells in the activated state that are potential targets for HIV-1 infection is low. We have investigated the ability of HIV-1 to infect resting T cells, and the consequences of such an infection. T cell activation was not required for HIV-1 infection; however, viral DNA was unable to integrate in resting T cells and was maintained extrachromosomally. Subsequent T cell activation allowed integration of extrachromosomal forms and led to a productive viral life cycle. Extrachromosomal forms of viral DNA were found to persist for several weeks after infection of resting T cells and, following T cell activation, these forms maintained their ability to integrate and act as a template for infectious virus. Several lines of evidence, including temporal analysis of HIV-1 replication and analysis of an HIV-1 integrase deletion mutant, indicated that extra-chromosomal HIV-1 DNA genomes were transcriptionally active. These results are compatible with a model whereby HIV-1 can persist in a non-productive extra-chromosomal state in resting T cells until subsequent antigen-induced or mitogen-induced T cell activation, virus integration and release. Thus agents that induce T cell activation may control the rate of HIV-1 replication and spread during AIDS progression

Active nuclear import of human immunodeficiency virus type 1 preintegration complexes.

After cell infection by the human immunodeficiency virus type 1 (HIV-1), nascent viral DNA in the form of a high molecular weight nucleoprotein preintegration complex must be transported to the nucleus of the host cell prior to integration of viral DNA with the host genome. The mechanism used by retroviruses for nuclear targeting of preintegration complexes and dependence on cell division has not been established. Our studies show that, after infection, the preintegration complex of HIV-1 was rapidly transported to the nucleus of the host cell by a process that required ATP but was independent of cell division. Functional HIV-1 integrase, an essential component of the preintegration complex, was not required for nuclear import of these complexes. The ability of HIV-1 to use host cell active transport processes for nuclear import of the viral preintegration complex obviates the requirement for host cell division in establishment of the integrated provirus. These findings are pertinent to our understanding of early events in the life cycle of HIV-1 and to the mode of HIV-1 replication in terminally differentiated nondividing cells such as macrophages (monocytes, tissue macrophages, follicular dendritic cells, and microglial cells)