Restricted Expression of Epstein-Barr Virus Latent Genes in Murine B Cells Derived from Embryonic Stem Cells

Background: Several human malignancies are associated with Epstein-Barr virus (EBV) and more than 95 % of the adult human population carries this virus lifelong. EBV efficiently infects human B cells and persists in this cellular compartment latently. EBV-infected B cells become activated and growth transformed, express a characteristic set of viral latent genes, and acquire the status of proliferating lymphoblastoid cell lines in vitro. Because EBV infects only primate cells, it has not been possible to establish a model of infection in immunocompetent rodents. Such a model would be most desirable in order to study EBV’s pathogenesis and latency in a suitable and amenable host. Methodology/Principal Findings: We stably introduced recombinant EBV genomes into mouse embryonic stem cells and induced their differentiation to B cells in vitro to develop the desired model. In vitro differentiated murine B cells maintained the EBV genomes but expression of viral genes was restricted to the latent membrane proteins (LMPs). In contrast to human B cells, EBV’s nuclear antigens (EBNAs) were not expressed detectably and growth transformed murine B cells did not arise in vitro. Aberrant splicing and premature termination of EBNA mRNAs most likely prevented the expression of EBNA genes required for B-cell transformation. Conclusions/Significance: Our findings indicate that fundamental differences in gene regulation between mouse and ma

Gammaherpesvirus Latency Accentuates EAE Pathogenesis: Relevance to Epstein-Barr Virus and Multiple Sclerosis

Epstein-Barr virus (EBV) has been identified as a putative environmental trigger of multiple sclerosis (MS), yet EBV's role in MS remains elusive. We utilized murine gamma herpesvirus 68 (γHV-68), the murine homolog to EBV, to examine how infection by a virus like EBV could enhance CNS autoimmunity. Mice latently infected with γHV-68 developed more severe EAE including heightened paralysis and mortality. Similar to MS, γHV-68EAE mice developed lesions composed of CD4 and CD8 T cells, macrophages and loss of myelin in the brain and spinal cord. Further, T cells from the CNS of γHV-68 EAE mice were primarily Th1, producing heightened levels of IFN-γ and T-bet accompanied by IL-17 suppression, whereas a Th17 response was observed in uninfected EAE mice. Clearly, γHV-68 latency polarizes the adaptive immune response, directs a heightened CNS pathology following EAE induction reminiscent of human MS and portrays a novel mechanism by which EBV likely influences MS and other autoimmune diseases

The Role of Social Networks in Health

The aim of this paper is to investigate how the social environment, composed also by social networks, influences health and what the role is. There is a reciprocal influence on that relation: as the networks can influence health, the health of a person contributes to networking with special features (may be groups of self‐help from trained individuals with the same health problem). Social networks have health effects, creating social support, access to health resources and social participation on welfare issues. Informal play a fundamental role in social support of people with little or no support systems. We must not, therefore, forget the importance that networks have to offer an effective social support by providing, for example, the needed caregivers, especially in the case of the chronically ill. An overall analysis is appropriate in addition to having a look at sociological type, and also considers epidemiological data. It’s what we do in our text. By integrating sociological aspects with ones purely epidemiological, we attempt to show how social networks have an effective role in the social determinants of health. This paper will try to develop the topic with a multi‐disciplinary approach focusing on the integration of the two disciplines

Morpho-dimensional analysis of the maxillary central incisor clinical crown in cases of congenitally missing upper lateral incisors

Aim: the purpose of this study was to analyse the crown morphology of maxillary central incisors in cases of agenesis of the upper lateral incisors, in order to establish patterns of associations between redu- ced mesio-distal dimensions of anterior teeth and tooth abnormalities in number. Materials and methods: the sample consisted of 31 patients with unilateral and bilateral absence of maxillary lateral in- cisors. Ninety six subjects without any agenesis were included in the control group. Mesio-distal widths of each central incisor crown we- re measured by means of 2 parameters; at the apical third of the crown and at the contact point. A Student’s t test was used to compare the results of each measurement within both group. Results: Significant differences were found in mesio-distal diameters at the contact points but not in the mesio-distal diameter at the apical third of the crown. Conclusions: It could be suggested that in case of cases of agene- sis of the lateral incisors the central incisors show a rectangular sha- pe of the crown instead of the trapezoid shape in subjects without age- nesis. These remarks should be considered before the orthodontic-pro- sthetic treatment is planned. A Olivadoti, T Doldo, M Treccani. Morpho-dimensional analysis of the maxillary central incisor clinical crown in cases of congenitally missing upper lateral incisors. Prog Orthod 2009;10(1):12-19