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591.
Variation in decision-making about end-of-life care among ethnic groups creates clinical conflicts. In order to understand changes in preferences for end-of-life care among Japanese who immigrate to the United States, we conducted 18 focus groups with 122 participants: 65 English-speaking Japanese Americans, 29 Japanese-speaking Japanese Americans and 28 Japanese living in Japan. Negative feelings toward living in adverse health states and receiving life-sustaining treatment in such states permeated all three groups. Fear of being meiwaku, a physical, psychological or financial caregiving burden on loved ones, was a prominent concern. They preferred to die pokkuri (popping off) before they become end stage or physically frail. All groups preferred group-oriented decision-making with family. Although advance directives were generally accepted, Japanese participants saw written directives as intrusive whereas Japanese Americans viewed them mainly as tools to reduce conflict created by dying person's wishes and a family's kazoku no jo--responsibility to sustain the dying patient. These findings suggest that in the United States Japanese cultural values concerning end-of-life care and decision-making process are largely preserved. 相似文献
592.
Uemura K Li M Tsutsumi T Yamazaki T Kawada T Kamiya A Inagaki M Sunagawa K Sugimachi M 《American journal of physiology. Heart and circulatory physiology》2007,293(4):H2254-H2261
Vagal nerve stimulation has been suggested to ameliorate left ventricular (LV) remodeling in heart failure. However, it is not known whether and to what degree vagal nerve stimulation affects matrix metalloproteinase (MMP) and tissue inhibitor of MMP (TIMP) in myocardium, which are known to play crucial roles in LV remodeling. We therefore investigated the effects of electrical stimulation of efferent vagal nerve on myocardial expression and activation of MMPs and TIMPs in a rabbit model of myocardial ischemia-reperfusion (I/R) injury. Anesthetized rabbits were subjected to 60 min of left coronary artery occlusion and 180 min of reperfusion with (I/R-VS, n = 8) or without vagal nerve stimulation (I/R, n = 7). Rabbits not subjected to coronary occlusion with (VS, n = 7) or without vagal stimulation (sham, n = 7) were used as controls. Total MMP-9 protein increased significantly after left coronary artery occlusion in I/R-VS and I/R to a similar degree compared with VS and sham values. Endogenous active MMP-9 protein level was significantly lower in I/R-VS compared with I/R. TIMP-1 mRNA expression was significantly increased in I/R-VS compared with the I/R, VS, and sham groups. TIMP-1 protein was significantly increased in I/R-VS and VS compared with the I/R and sham groups. Cardiac microdialysis technique demonstrated that topical perfusion of acetylcholine increased dialysate TIMP-1 protein level, which was suppressed by coperfusion of atropine. Immunohistochemistry demonstrated a strong expression of TIMP-1 protein in cardiomyocytes around the dialysis probe used to perfuse acetylcholine. In conclusion, in a rabbit model of myocardial I/R injury, vagal nerve stimulation induced TIMP-1 expression in cardiomyocytes and reduced active MMP-9. 相似文献
593.
Arabidopsis thaliana encodes four Dicer-like (DCL) proteins and five dsRNA-binding (DRB) proteins. We have previously demonstrated that DCL4 specifically
interacts with DRB4 in vitro. Here we describe the interaction between DCL4 and DRB4 in vivo. The phenotype of a mutant with
a defect in DCL4 (dcl4-2) was similar to that of a mutant with a defect in DRB4 (drb4-1): both mutant plants had elongated and downwardly curled rosette leaves and over-accumulated anthocyanin. In immunoprecipitation
experiments with either anti-DCL4 or anti-DRB4 antibody and crude extracts of wild-type Arabidopsis plants, co-immunoprecipitation of DCL4 and DRB4 was detected, indicating that DCL4 interacts with DRB4 in vivo. This interaction
was confirmed by immunoprecipitation experiments using extracts from dcl4-2, drb4-1, or transgenic plants expressing the hemagglutinin-tagged version of DCL4 or DRB4. The results of immunoprecipitation experiments
also suggest that most DCL4 is associated with DRB4, but that some DRB4 is free or associated with other proteins. Reduced
accumulation of the TAS1 and TAS3
trans-acting siRNA (ta-siRNA) and over accumulation of their target mRNAs (At5g18040 and auxin response factors ARF3 and ARF4) were detected in both drb4-1 and dcl4-2 mutants. These results indicate that DRB4, together with DCL4, functions in the ta-siRNA biogenesis.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Yukihiro Nakazawa and Akihiro Hiraguri contributed equally to this work. 相似文献
594.
Kazuhiko Udagawa Yasuo Niki Toshiyuki Kikuchi Yusuke Fukuhara Yuki Takeda Takeshi Miyamoto Morio Matsumoto Masaya Nakamura 《The journal of histochemistry and cytochemistry》2021,69(4):245
Interleukin (IL)-1 plays a key role in carcinogenesis, tumor progression, and metastasis. Although IL-1 may enhance the expansion of CD8+ T-cells, the pathological contribution of IL-1-activated CD8+ T-cells to tumor metastasis remains unclear. This study used a liver metastasis model of the EL4 T-cell lymphoma cells transplanted into human IL (hIL)-1α conditional transgenic (hIL-1α cTg) mice. Overproduction of hIL-1α suppressed both macroscopic and histological liver metastasis of EL4 T-cell lymphoma. The hIL-1α-induced inflammatory state increased the number of CD8+ T-cells both within and around metastatic tumors. Moreover, larger numbers of CD8+ T-cells showed greater infiltration of liver blood vessels in hIL-1α cTg mice than in control wild-type mice. Terminal deoxynucleotidyl transferase dUTP nick-end labeling staining of liver tissue from hIL-1α cTg mice indicated increased apoptosis of cells in the tumor. Localization of apoptosis cells resembled that of CD8+ T-cells. In addition, cytotoxicity assay showed that CD8+ T-cell counts from tumor-bearing hIL-1α cTg mice correlated with cytotoxicity against EL4. In summary, IL-1α suppresses lymphoma metastasis, and IL-1α-activated CD8+ T-cells may play important roles in inhibiting both tumor metastasis and metastatic tumor growth: 相似文献
595.
Keisuke Ikawa Ayaka Satou Mitsuko Fukuhara Shigeru Matsumura Naoyuki Sugiyama Hidemasa Goto 《Cell cycle (Georgetown, Tex.)》2014,13(1):126-137
Endocytic vesicle fusion is inhibited during mitosis, but the molecular pathways that mediate the inhibition remain unclear. Here we uncovered an essential role of Polo-like kinase 1 (Plk1) in this mechanism. Phosphoproteomic analysis revealed that Plk1 phosphorylates the intermediate filament protein vimentin on Ser459, which is dispensable for its filament formation but is necessary for the inhibition of endocytic vesicle fusion in mitosis. Furthermore, this mechanism is required for integrin trafficking toward the cleavage furrow during cytokinesis. Our results thus identify a novel mechanism for fusion inhibition in mitosis and implicate its role in vesicle trafficking after anaphase onset. 相似文献
596.
Akifumi Ohtaka Makoto Uenishi Linda Wulandari Yulintine Liwat Ardianor Sulmin Gumiri Masao Nagasaka Haruo Fukuhara 《Limnology》2014,15(2):191-197
The faunal composition of “interrhizon” invertebrate communities associated with submerged parts of three kinds of macrophytes, Eichhornia crassipes, Gramineae spp. and Polygonum tomentosum, were studied in an oxbow lake, Lake Tundai, with acidic water (pH 3.9–4.4) in the peat swamp area of Central Kalimantan. The pH, turbidity, and chlorophyll-a concentration in the surface waters tended to be higher in macrophyte stands than in open waters near the stands. Thirty-one taxa belonging to three groups of invertebrates, Arachnida, Insecta, especially chironomids, and Isopoda, were found from the root systems, of which insects were the most abundant in every macrophyte stand. The interrhizon invertebrates accounted for 0.16–8.7 g wet wt m?2 among three vegetational stands. The diversity and abundance of interrhizon invertebrates are low in Lake Tundai; this could be due to low pH and/or low productivity in the lake water. 相似文献
597.
Jun Ueda Jolene Caifeng Ho Kian Leong Lee Shojiro Kitajima Henry Yang Wendi Sun Noriko Fukuhara Norazean Zaiden Shing Leng Chan Makoto Tachibana Yoichi Shinkai Hiroyuki Kato Lorenz Poellinger 《Molecular and cellular biology》2014,34(19):3702-3720
Hypoxia promotes stem cell maintenance and tumor progression, but it remains unclear how it regulates long-term adaptation toward these processes. We reveal a striking downregulation of the hypoxia-inducible histone H3 lysine 9 (H3K9) demethylase JMJD1A as a hallmark of clinical human germ cell-derived tumors, such as seminomas, yolk sac tumors, and embryonal carcinomas. Jmjd1a was not essential for stem cell self-renewal but played a crucial role as a tumor suppressor in opposition to the hypoxia-regulated oncogenic H3K9 methyltransferase G9a. Importantly, loss of Jmjd1a resulted in increased tumor growth, whereas loss of G9a produced smaller tumors. Pharmacological inhibition of G9a also resulted in attenuation of tumor growth, offering a novel therapeutic strategy for germ cell-derived tumors. Finally, Jmjd1a and G9a drive mutually opposing expression of the antiangiogenic factor genes Robo4, Igfbp4, Notch4, and Tfpi accompanied by changes in H3K9 methylation status. Thus, we demonstrate a novel mechanistic link whereby hypoxia-regulated epigenetic changes are instrumental for the control of tumor growth through coordinated dysregulation of antiangiogenic gene expression. 相似文献
598.
Syun‐Ichi Urayama Toshiyuki Fukuhara Hiromitsu Moriyama Akio Toh‐E Susumu Kawamoto 《Microbiology and immunology》2014,58(5):294-302
Magnaporthe oryzae chrysovirus 1 strain A (MoCV1‐A) is the causal agent of growth repression and attenuated virulence (hypovirulence) of the rice blast fungus, M. oryzae. We have previously reported that heterologous expression of MoCV1‐A ORF4 in Saccharomyces cerevisiae results in growth defects, a large central vacuole and other cytological changes. In this study, the effects of open reading frame (ORF) 4 expression in Cryptococcus neoformans, a human pathogenic fungus responsible for severe opportunistic infection, were investigated. Cells expressing the ORF4 gene in C. neoformans showed remarkably enlarged vacuoles, nuclear diffusion and a reduced growth rate. In addition, expression of ORF4 apparently suppressed formation of the capsule that surrounds the entire cell wall, which is one of the most important components of expression of virulence. After 5‐fluoroorotic acid treatment of ORF4‐expressing cells to remove the plasmid carrying the ORF4 gene, the resultant plasmid‐free cells recovered normal morphology and growth, indicating that heterologous expression of the MoCV1‐A ORF4 gene induces negative effects in C. neoformans. These data suggest that the ORF4 product is a candidate for a pharmaceutical protein to control disease caused by C. neoformans. 相似文献
599.
Background
Comatose patients with acute intracerebral hemorrhage (ICH) diagnosed as inoperative due to their severe comorbidity will be treated differently between countries. In certain countries including Japan, aggressive medical care may be performed according to the patients'' family requests although the effects on the outcome are obscure. For respiratory distress in comatose patients with inoperative acute ICH, the role of mechanical ventilation on the outcome is unknown. We speculated that the efficacy of a ventilator in such a specific condition is limited and possibly futile.Methods
We retrospectively evaluated the in-hospital mortality and further outcome of 65 comatose patients with inoperative ICH. Among the patients, 56 manifested respiratory distress, and the effect of the ventilator was evaluated by comparing the patients treated with and without the ventilator.Results
The in-hospital mortality was calculated as 80%. A statistically significant parameter affecting the mortality independently was the motor subset on the Glasgow Coma Scale (P = 0.015). Among the patients who manifested respiratory distress, 7.7% of patients treated with a ventilator and 14.0% of patients not treated with a ventilator survived; an outcome is not significantly different. The mean survival duration of patients treated with a ventilator was significantly longer than the mean survival duration of patients not treated with a ventilator (P = 0.021). Among the surviving 13 patients, 7 patients died 5 to 29 months after onset without significant consciousness recovery. Another 6 patients suffered continuous disablement due to prolonged severe consciousness disturbances.Conclusion
The current results indicate that treating comatose patients resulting from inoperative acute ICH may be futile. In particular, treating these patients with a ventilator only has the effect of prolonging unresponsive life, and the treatment may be criticized from the perspective of the appropriate use of public medical resources. 相似文献600.
Periodontal diseases result from inflammation by bacterial infection in plaques, leading to tooth loss. However, regenerative approaches with periodontal tissue regeneration by guided tissue regeneration and enamel matrix derivative are not yet well established. Tissue regeneration requires three factors: cells, scaffold, and growth factors. Dedifferentiated fat cells (DFATs) are pluripotent with the same differentiation capacities as mesenchymal stem cells (MSCs). Access to MSCs is limited, whereas donor cells for DFATs are abundant in adipose tissues and can be non-invasively obtained. Therefore, we tested DFATs as a new source for periodontal tissue regeneration in an experimental periodontal tissue loss model in rats by transplanting DFATs on an atelocollagen scaffold using DFATs isolated from Sprague–Dawley (SD) rats expressing green fluorescent protein (GFP). GFP–DFAT cells were transplanted on the palatal side of the upper left first molar in SD rats and detected by H&E staining, GFP, and proliferating cell nuclear antigen (PCNA) expression. DFAT differentiation was also evaluated in three-dimensional cultures. GFP positive cells were detected in the regenerated tissue by the DFATs/scaffold mixture at 4 weeks after transplantation, and PCNA-positive cells were significantly increased in the periodontal ligament along the new bone in the DFATs/scaffold group more than in the scaffold-only group, suggesting that DFATs differentiate in the same manner as MSCs and regenerate in the defective areas. Consistent with previous reports, DFATs differentiation was slower than that with stem cells. The present study demonstrates that DFATs are pluripotent and an effective new source of cells for periodontal tissue regeneration. 相似文献