Pneumonia incidence and oral health management by dental hygienists in long-term care facilities: A 1-year prospective multicentre cohort study.

OBJECTIVE: To investigate the association between oral health management (OHM) by dental hygienists and the occurrence of pneumonia, and determine the effectiveness of OHM in pneumonia prevention. BACKGROUND: In long-term care facilities in Japan, the need for professional OHM is increasing with an increase in the number of severely debilitated residents. MATERIALS AND METHODS: A 1-year prospective multicentre cohort study was conducted using data from 504 residents (63 men; mean age: 87.4 ± 7.8 years) in Japanese long-term care facilities. Basic information, medical history, willingness to engage in oral hygiene behaviour, need for OHM and oral conditions were investigated at baseline. In addition, information on the occurrence of pneumonia was collected using a follow-up survey after one year. A Poisson regression analysis with robust standard errors was conducted, with pneumonia as the dependent variable, and factors associated with OHM and pneumonia occurrence as explanatory variables. RESULTS: Overall, 349 (69.2%) residents required OHM by dental hygienists during that year of follow-up. Of those, 238 (68.2%) were provided with OHM, and 18 (7.5%) developed pneumonia. Among the 111 patients (31.8%) who were not provided with OHM, 21 (18.9%) developed pneumonia. The OHM group had lower pneumonia rates than the non-OHM group (prevalence rate ratio: 0.374; 95% CI: 0.210-0.665). CONCLUSION: Oral health management by dental hygienists was associated with a lower incidence of pneumonia among residents of long-term care facilities, underlining the importance of professional OHM for such individuals. It is recommended that OHM be practised routinely in long-term care facilities.

Differential requirements of cellular and humoral immune responses for Fv2-associated resistance to erythroleukemia and for regulation of retrovirus-induced myeloid leukemia development.

To assess the possible contribution of host immune responses to the exertion of Fv2-associated resistance to Friend virus (FV)-induced disease development, we inoculated C57BL/6 (B6) mice that lacked various subsets of lymphocytes with FV containing no lactate dehydrogenase-elevating virus. Fv2(r) B6 mice lacking CD4(+) T cells developed early polycythemia and fatal erythroleukemia, while B6 mice lacking CD8(+) T cells remained resistant. Erythroid progenitor cells infected with spleen focus-forming virus (SFFV) were eliminated, and no polycythemia was observed in B cell-deficient B6 mice, but they later developed myeloid leukemia associated with oligoclonal integration of ecotropic Friend murine leukemia virus. Additional depletion of natural killer and/or CD8(+) T cells from B cell-deficient B6 mice resulted in the expansion of SFFV proviruses and the development of polycythemia, indicating that SFFV-infected erythroid cells are not only restricted in their growth but are actively eliminated in Fv2(r) mice through cellular immune responses.

Comparing the effects of different individualized music interventions for elderly individuals with severe dementia.

BACKGROUND: Individuals with dementia often experience poor quality of life (QOL) due to behavioral and psychological symptoms of dementia (BPSD). Music therapy can reduce BPSD, but most studies have focused on patients with mild to moderate dementia. We hypothesized that music intervention would have beneficial effects compared with a no-music control condition, and that interactive music intervention would have stronger effects than passive music intervention. METHODS: Thirty-nine individuals with severe Alzheimer's disease were randomly and blindly assigned to two music intervention groups (passive or interactive) and a no-music Control group. Music intervention involved individualized music. Short-term effects were evaluated via emotional response and stress levels measured with the autonomic nerve index and the Faces Scale. Long-term effects were evaluated by BPSD changes using the Behavioral Pathology in Alzheimer's Disease (BEHAVE-AD) Rating Scale. RESULTS: Passive and interactive music interventions caused short-term parasympathetic dominance. Interactive intervention caused the greatest improvement in emotional state. Greater long-term reduction in BPSD was observed following interactive intervention, compared with passive music intervention and a no-music control condition. CONCLUSION: Music intervention can reduce stress in individuals with severe dementia, with interactive interventions exhibiting the strongest beneficial effects. Since interactive music intervention can restore residual cognitive and emotional function, this approach may be useful for aiding severe dementia patients' relationships with others and improving QOL. The registration number of the trial and the name of the trial registry are UMIN000008801 and "Examination of Effective Nursing Intervention for Music Therapy for Severe Dementia Elderly Person" respectively.

Premature terminal exhaustion of Friend virus-specific effector CD8+ T cells by rapid induction of multiple inhibitory receptors.

During chronic viral infection, persistent exposure to viral Ags leads to the overexpression of multiple inhibitory cell-surface receptors that cause CD8(+) T cell exhaustion. The severity of exhaustion correlates directly with the level of infection and the number and intensity of inhibitory receptors expressed, and it correlates inversely with the ability to respond to the blockade of inhibitory pathways. Friend virus (FV) is a murine retrovirus complex that induces acute high-level viremia, followed by persistent infection and leukemia development, when inoculated into immunocompetent adult mice. In this article, we provide conclusive evidence that FV infection results in the generation of virus-specific effector CD8(+) T cells that are terminally exhausted. Acute FV-induced disease is characterized by a rapid increase in the number of virus-infected erythroblasts, leading to massive splenomegaly. Most of the expanded erythroblasts strongly express programmed death ligand-1 and MHC class I, thereby creating a highly tolerogenic environment. Consequently, FV-specific effector CD8(+) T cells uniformly express multiple inhibitory receptors, such as programmed cell death 1 (PD-1), T cell Ig domain and mucin domain 3 (Tim-3), lymphocyte activation gene-3, and CTLA-4, rapidly become nonresponsive to restimulation and are no longer reinvigorated by combined in vivo blockade of PD-1 and Tim-3 during the memory phase. However, combined blockade of PD-1 and Tim-3 during the priming/differentiation phase rescued FV-specific CD8(+) T cells from becoming terminally exhausted, resulting in improved CD8(+) T cell functionality and virus control. These results highlight FV's unique ability to evade virus-specific CD8(+) T cell responses and the importance of an early prophylactic approach for preventing terminal exhaustion of CD8(+) T cells.

Mouse APOBEC3 restricts friend leukemia virus infection and pathogenesis in vivo.

Several members of the apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like complex 3 (APOBEC3) family in primates act as potent inhibitors of retroviral replication. However, lentiviruses have evolved mechanisms to specifically evade host APOBEC3. Likewise, murine leukemia viruses (MuLV) exclude mouse APOBEC3 from the virions and cleave virion-incorporated APOBEC3. Although the betaretrovirus mouse mammary tumor virus has been shown to be susceptible to mouse APOBEC3, it is not known if APOBEC3 has a physiological role in restricting more widely distributed and long-coevolved mouse gammaretroviruses. The pathogenicity of Friend MuLV (F-MuLV) is influenced by several host genes: some directly restrict the cell entry or integration of the virus, while others influence the host immune responses. Among the latter, the Rfv3 gene has been mapped to chromosome 15 in the vicinity of the APOBEC3 locus. Here we have shown that polymorphisms at the mouse APOBEC3 locus indeed influence F-MuLV replication and pathogenesis: the APOBEC3 alleles of F-MuLV-resistant C57BL/6 and -susceptible BALB/c mice differ in their sequences and expression levels in the hematopoietic tissues and in their abilities to restrict F-MuLV replication both in vitro and in vivo. Furthermore, upon infection with the pathogenic Friend virus complex, (BALB/c x C57BL/6)F(1) mice displayed an exacerbated erythroid cell proliferation when the mice carried a targeted disruption of the C57BL/6-derived APOBEC3 allele. These results indicate, for the first time, that mouse APOBEC3 is a physiologically functioning restriction factor to mouse gammaretroviruses.

Reversible heterolysis of H2 mediated by an M-S(thiolate) bond (M = Ir, Rh): a mechanistic implication for [NiFe] hydrogenase.

Facile H2 heterolysis was found to be mediated by coordinatively unsaturated Cp*Ir and Cp*Rh thiolate complexes. The reaction of iridium complex is reversible, and the formation of an intermediary Ir-H/thiol complex was detected. The reversible conversion between thiolate complex+H2 and hydride complex+thiol provides an intriguing functional model of [NiFe] hydrogenase.