Astrocytic growth through the autocrine/paracrine production of IL-1ß in the early infectious phase of fowl glioma-inducing virus.

Fowl glioma is characterized morphologically by multiple nodular astrocytic growth with disseminated non-suppurative encephalitis. The disease is caused by fowl glioma-inducing virus (FGV) and its variants, belonging to subgroup A of avian leukosis virus (ALV-A). Fifty-seven FGV variants have so far been isolated from Japanese fowls and these variants have a variable degree of glioma inducibility. However, how these ALVs induce glioma with different degrees and frequencies has not been fully elucidated. In this study, we investigated the relationship between intracerebral viral replication and astrocytic growth in the early infectious phase. Replication abilities of two ALV strains, Sp-53 (a FGV variant) and ALV-based replication-competent vector RCAS(A) without glioma inducibility, were compared in the brains of C/O specific pathogen free chickens at 35 days of age. Sp-53 replicated faster than RCAS(A), and the histological score and the level of interleukin (IL)-1ß in brains increased depending on the level of intracerebral viral RNA. Up-regulation of IL-1ß was also demonstrated in primary cultured astrocytes. These results suggest that the astrocytic growth in this phase is enhanced through the autocrine/paracrine production of IL-1ß in the FGV-infected astrocytes.

Caregiver-reported dementia as a predictor of oral health among patients receiving home-visit dental treatment: A retrospective cohort study.

OBJECTIVE: To assess caregiver-reported dementia as a risk factor for retained roots, an indicator of poor oral hygiene, among patients receiving home-visit dental treatment in Japan. METHODS: The medical records of 231 dentate patients who received home-visit dental treatment (covered by public medical insurance) for more than 2 years were retrospectively analyzed. The number of teeth and retained roots at the initial and final examinations were obtained from the dental charts, and the "change in the number of retained roots from initial to final examination" was determined. The presence or absence of caregiver-reported dementia, diabetes, and osteoporosis, as well as the level of long-term care needed, were used as indicators of general health condition at the initial interview. Multiple regression analyses were conducted in five models that tested the association of independent variables (age, gender, observation period, general health, presence or absence of caregiver-reported dementia at the initial interview) with changes in the number of retained roots. RESULTS: In all models, the presence of caregiver-reported dementia at the initial interview was significantly associated with the change in the number of retained roots (p < .05). The adjusted coefficient of determination (R2 ) of model 5, which included all the predetermined independent factors, was .168. CONCLUSIONS: Caregiver-reported dementia may be a risk factor for an increase in the number of retained roots among patients who receive home-visit dental treatment and may serve as an indicator of the need for regular and proactive oral hygiene management.

Cardiac pathology and molecular epidemiology by avian leukosis viruses in Japan.

Epidemiological studies suggest that retroviruses, including human immunodeficiency virus type 1, are associated with cardiomyopathy and myocarditis, but a causal relationship remains to be established. We encountered unusual cardiomyocyte hypertrophy and mitosis in Japanese native fowls infected with subgroup A of the avian leukosis viruses (ALVs-A), which belong to the genus Alpharetrovirus of the family Retroviridae and mainly induce lymphoid neoplasm in chickens. The affected hearts were evaluated by histopathology and immunohistochemistry, viral isolation, viral genome sequencing and experimental infection. There was non-suppurative myocarditis in eighteen fowls and seven of them had abnormal cardiomyocytes, which were distributed predominantly in the left ventricular wall and showed hypertrophic cytoplasm and atypical large nuclei. Nuclear chains and mitosis were frequently noted in these cardiomyocytes and immunohistochemistry for proliferating cell nuclear antigen supported the enhancement of mitotic activity. ALVs were isolated from all affected cases and phylogenic analysis of envSU genes showed that the isolates were mainly classified into two different clusters, suggesting viral genome diversity. In ovo experimental infection with two of the isolates was demonstrated to cause myocarditis and cardiomyocyte hypertrophy similar to those in the naturally occurring lesions and cardiac hamartoma (rhabdomyoma) in a shorter period of time (at 70 days of age) than expected. These results indicate that ALVs cause myocarditis as well as cardiomyocyte abnormality in chickens, implying a pathogenetic mechanism different from insertional mutagenesis and the existence of retrovirus-induced heart disorder.