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This paper describes the effect of aspect ratio on mixed convection in a horizontal rectangular duct with heated and cooled side walls numerically and experimentally. In the numerical analysis, fluid flow and temperature distributions for Ri=1.61, Pr=6.99, Re=100 and aspect ratio, Ar=0.2-10, were obtained by solving dimensionless governing equations using the SIMPLE procedure. The QUICK scheme was applied to the convective term of these equations. In the experimental analysis, the flow behavior for Ar=0.5-2 was visualized by the dye-injection method. Numerical results showed that the swirl flow was generated along the flow direction, and its pitch length was influenced by Ar. The pitch length was the shortest when Ar=0.5-1, and this tendency was the same in numerical results and experimental results. The heat transfer behavior was also discussed corresponding to the flow, and the heat transfer ratio was highest at Ar=1 in 0.2 ≤ Ar ≤ 10. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.20391 [ABSTRACT FROM AUTHOR]

Although the methylation status of histone H3K27 plays a critical role in CD4 + T cell differentiation and its function, the role of Utx histone H3K27 demethylase in the CD8 + T cell-dependent immune response remains unclear. We therefore generated T cell-specific Utx flox/flox Cd4-Cre Tg ( Utx KO) mice to determine the role of Utx in CD8 + T cells. Wild-type (WT) and Utx KO mice were infected with Listeria monocytogenes expressing OVA to analyze the immune response of Ag-specific CD8 + T cells. There was no significant difference in the number of Ag-specific CD8 + T cells upon primary infection between WT and Utx KO mice. However, Utx deficiency resulted in more Ag-specific CD8 + T cells upon secondary infection. Adoptive transfer of Utx KO CD8 + T cells resulted in a larger number of memory cells in the primary response than in WT. We observed a decreased gene expression of effector-associated transcription factors, including Prdm1 encoding Blimp1, in Utx KO CD8 + T cells. We confirmed that the trimethylation level of histone H3K27 in the Prdm1 gene loci in the Utx KO cells was higher than in the WT cells. The treatment of CD8 + T cells with Utx-cofactor α-ketoglutarate hampered the memory formation, whereas Utx inhibitor GSK-J4 enhanced the memory formation in WT CD8 + T cells. These data suggest that Utx negatively controls the memory formation of Ag-stimulated CD8 + T cells by epigenetically regulating the gene expression. Based on these findings, we identified a critical link between Utx and the differentiation of Ag-stimulated CD8 + T cells., (Copyright © 2019 by The American Association of Immunologists, Inc.)

The antitumor activity of activated CD8+ T cells in the tumor microenvironment seems to be limited due to their being metabolically unfit. This metabolic unfitness is closely associated with T-cell exhaustion and impairment of memory formation, which are barriers to successful antitumor adoptive immunotherapy. We therefore assessed the role of glutamine metabolism in the antitumor activity of CD8 + T cells using a tumor-inoculated mouse model. The adoptive transfer of tumor-specific CD8 + T cells cultured under glutamine-restricted (dGln) conditions or CD8 + T cells treated with specific inhibitors of glutamine metabolism efficiently eliminated tumors and led to better survival of tumor-inoculated mice than with cells cultured under control (Ctrl) conditions. The decreased expression of PD-1 and increased Ki67 positivity among tumor-infiltrating CD8 + T cells cultured under dGln conditions suggested that the inhibition of glutamine metabolism prevents CD8 + T-cell exhaustion in vivo. Furthermore, the transferred CD8 + T cells cultured under dGln conditions expanded more efficiently against secondary OVA stimulation than did CD8 + T cells under Ctrl conditions. We found that the expression of a pro-survival factor and memory T cell-related transcription factors was significantly higher in CD8 + T cells cultured under dGln conditions than in those cultured under Ctrl conditions. Given these findings, our study uncovered an important role of glutamine metabolism in the antitumor activity of CD8 + T cells. The novel adoptive transfer of tumor-specific CD8 + T cells cultured in glutamine-restricted conditions may be a promising approach to improve the efficacy of cell-based adoptive immunotherapy., (© 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Purpose: To investigate the trend in the number of Acanthamoeba keratitis (AK) cases in Japan., Method: A survey was conducted in 48 university hospitals. Patients who were diagnosed with AK from January 2007 to December 2011 were enrolled. The trend in the number of cases and the type of contact lenses (CLs) that patients used were studied., Results: A total of 524 patients was studied. The numbers of AK cases in each year, from 2007 to 2011, were 105, 152, 155, 65, and 47. The number dropped markedly after 2009. The percentage of conventional soft CLs and frequent replacement soft CL users that needed daily care such as rubbing-washing also dropped after 2008., Conclusion: The number of AK cases in Japan has been decreasing in recent years. The cause is uncertain, but one possibility is that information about proper CL care promulgated by ophthalmic societies in recent years is producing results.