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991.
992.
Toshinobu Nishimura Shin Kaneko Ai Kawana-Tachikawa Yoko Tajima Haruo Goto Dayong Zhu Kaori Nakayama-Hosoya Shoichi Iriguchi Yasushi Uemura Takafumi Shimizu Naoya Takayama Daisuke Yamada Ken Nishimura Manami Ohtaka Nobukazu Watanabe Satoshi Takahashi Aikichi Iwamoto Haruhiko Koseki Hiromitsu Nakauchi 《Cell Stem Cell》2013,12(1):114-126
Highlights? Reprogramming of antigen-specific T cells to generate iPSCs (T-iPSCs) ? Redifferentiation of CD8+ T cells, with original antigen specificity, from T-iPSCs ? Newly differentiated T cells show high proliferation and elongated telomeres ? T cell antigen-specific cytotoxicity is maintained 相似文献
993.
Yilong Ai Siyuan Wu Hai Gao Haigang Wei Zhe Tang Xia Li Chen Zou 《Journal of cellular and molecular medicine》2021,25(23):10857-10868
Immunotherapy has been identified a promising treatment of cancers, including Oral squamous cell carcinoma (OSCC). CRNDE is highly overexpressed in various cancers. Many lncRNAs have been reported in CD8 T lymphocytes. Little is investigated about their effects in the functions of CD8 + T cells in OSCC. Currently, the influence of lncRNA CRNDE on the function of CD8 + T cells in OSCC progression was investigated. Here, CRNDE was obviously elevated and negatively correlated with IFN-γ production in tumour-infiltrating CD8 + T cells isolated from OSCC patients. CRNDE can exhibit a crucial role in activating CD8 + T-cell exhaustion. Mechanistically, CRNDE specifically sponged miR-545-5p to induce T-cell immunoglobulin and mucin domain-3 (TIM-3), thus contributing to CD8 + T-cell exhaustion. The function of miR-545-5p on T-cell function remains poorly known. TIM-3 is a significant immune checkpoint, and it inhibits cancer immunity. TIM-3 can demonstrate an important role in CD8 + T-cell exhaustion. In summary, loss of CRNDE could induce miR-545-5p and inhibit TIM3 expression, thus significantly activated the anti-tumour effect of CD8 + T cells. 相似文献
994.
Ai Guo Kai Li Hong-Chuan Tian Zhen Fan Qiu-Nan Chen Yun-Fei Yang Jing Yu Yong-Xin Wu Qian Xiao 《Journal of cellular and molecular medicine》2021,25(7):3585-3600
Obesity is associated with biological dysfunction in skeletal muscle. As a condition of obesity accompanied by muscle mass loss and physical dysfunction, sarcopenic obesity (SO) has become a novel public health problem. Human fibroblast growth factor 19 (FGF19) plays a therapeutic role in metabolic diseases. However, the protective effects of FGF19 on skeletal muscle in obesity and SO are still not completely understood. Our results showed that FGF19 administration improved muscle loss and grip strength in young and aged mice fed a high-fat diet (HFD). Increases in muscle atrophy markers (FOXO-3, Atrogin-1, MuRF-1) were abrogated by FGF19 in palmitic acid (PA)-treated C2C12 myotubes and in the skeletal muscle of HFD-fed mice. FGF19 not only reduced HFD-induced body weight gain, excessive lipid accumulation and hyperlipidaemia but also promoted energy expenditure (PGC-1α, UCP-1, PPAR-γ) in brown adipose tissue (BAT). FGF19 treatment restored PA- and HFD-induced hyperglycaemia, impaired glucose tolerance and insulin resistance (IRS-1, GLUT-4) and mitigated the PA- and HFD-induced decrease in FNDC-5/irisin expression. However, these beneficial effects of FGF19 on skeletal muscle were abolished by inhibiting AMPK, SIRT-1 and PGC-1α expression. Taken together, this study suggests that FGF19 protects skeletal muscle against obesity-induced muscle atrophy, metabolic derangement and abnormal irisin secretion partially through the AMPK/SIRT-1/PGC-α signalling pathway, which might be a potential therapeutic target for obesity and SO. 相似文献
995.
Yusuke Ohsaki Hitoshi Shirakawa Akihito Miura Puspo E. Giriwono Shoko Sato Ai Ohashi Maiko Iribe Tomoko Goto Michio Komai 《The Journal of nutritional biochemistry》2010,21(11):1120-1126
Vitamin K is essential for blood coagulation and bone metabolism in mammals. This vitamin functions as a cofactor in the posttranslational synthesis of γ-carboxyglutamic acid (Gla) from glutamic acid residues. However, other functions of vitamin K have been reported recently. We previously found that vitamin K suppresses the inflammatory reaction induced by lipopolysaccharide (LPS) in rats and human macrophage-like THP-1 cells. In this study, we further investigated the mechanism underlying the anti-inflammatory effect of vitamin K by using cultures of LPS-treated human- and mouse-derived cells. All the vitamin K analogues analyzed in our study exhibited varied levels of anti-inflammatory activity. The isoprenyl side chain structures, except geranylgeraniol, of these analogues did not show such activity; warfarin did not interfere with this activity. The results of our study suggest that the 2-methyl-1,4-naphtoquinone ring structure contributes to express the anti-inflammatory activity, which is independent of the Gla formation activity of vitamin K. Furthermore, menaquinone-4, a form of vitamin K2, reduced the activation of nuclear factor κB (NFκB) and inhibited the phosphorylation of IKKα/β after treatment of cells with LPS. These results clearly show that the anti-inflammatory activity of vitamin K is mediated via the inactivation of the NFκB signaling pathway. 相似文献
996.
Ai Koyanagi Noe Garin Beatriz Olaya Jose Luis Ayuso-Mateos Somnath Chatterji Matilde Leonardi Seppo Koskinen Beata Tobiasz-Adamczyk Josep Maria Haro 《PloS one》2014,9(12)
BackgroundData on the association between chronic conditions or the number of chronic conditions and sleep problems in low- or middle-income countries is scarce, and global comparisons of these associations with high-income countries have not been conducted.MethodsData on 42116 individuals 50 years and older from nationally-representative samples of the Collaborative Research on Ageing in Europe (Finland, Poland, Spain) and the World Health Organization''s Study on Global Ageing and Adult Health (China, Ghana, India, Mexico, Russia, South Africa) conducted between 2011–2012 and 2007–2010 respectively were analyzed.ResultsThe association between nine chronic conditions (angina, arthritis, asthma, chronic lung disease, depression, diabetes, hypertension, obesity, and stroke) and self-reported severe/extreme sleep problems in the past 30 days was estimated by logistic regression with multiple variables. The age-adjusted prevalence of sleep problems ranged from 2.8% (China) to 17.0% (Poland). After adjustment for confounders, angina (OR 1.75–2.78), arthritis (OR 1.39–2.46), and depression (OR 1.75–5.12) were significantly associated with sleep problems in the majority or all of the countries. Sleep problems were also significantly associated with: asthma in Finland, Spain, and India; chronic lung disease in Poland, Spain, Ghana, and South Africa; diabetes in India; and stroke in China, Ghana, and India. A linear dose-dependent relationship between the number of chronic conditions and sleep problems was observed in all countries. Compared to no chronic conditions, the OR (95%CI) for 1,2,3, and≥4 chronic conditions was 1.41 (1.09–1.82), 2.55 (1.99–3.27), 3.22 (2.52–4.11), and 7.62 (5.88–9.87) respectively in the overall sample.ConclusionsIdentifying co-existing sleep problems among patients with chronic conditions and treating them simultaneously may lead to better treatment outcome. Clinicians should be aware of the high risk for sleep problems among patients with multimorbidity. Future studies are needed to elucidate the best treatment options for comorbid sleep problems especially in developing country settings. 相似文献
997.
Seema Untawale Andrew O. Odegaard Woon-Puay Koh Ai Zhen Jin Jian-Min Yuan Kristin E. Anderson 《PloS one》2014,9(1)
Few studies have examined the association between body mass index (BMI: kg/m2) and pancreatic cancer risk in Asian populations. We examined this relationship in 51,251 Chinese men and women aged 45–74 who enrolled between 1993 and 1998 in the population based, prospective Singapore Chinese Health Study. Data were collected through in-person interviews. By December 31, 2011, 194 cohort participants had developed pancreatic cancer. A Cox proportional hazards model was used to estimate hazard ratios (HR) and their 95% confidence intervals (95% CI). We hypothesized the association between BMI and pancreatic cancer risk may vary by smoking status (ever v. never) and there was evidence for this as the interaction between BMI and smoking status was significant (p = 0.018). Among ever smokers, being classified as underweight (BMI <18.5 kg/m2), was associated with a significantly elevated risk of pancreatic cancer relative to smokers with a BMI of 21.5–24.4 kg/m2 (HR = 1.99, 95% CI = 1.03–3.84). This association was strengthened after exclusion of the first three years of follow-up time. Among never smokers, there was no association between BMI and pancreatic cancer risk. However, after excluding pancreatic cancer cases and person-years in the first three years of follow-up, never smokers with a BMI ≥ 27.5 kg/m2 showed a suggestive increased risk of pancreatic cancer relative to never smokers with a BMI of 21.5–24.4 kg/m2 (HR = 1.75, 95% CI = 0.93–3.3). In conclusion, Singaporean Chinese who were underweight with a history of smoking had an increased risk of developing pancreatic cancer, whereas there was no significant association between BMI and pancreatic cancer in never smokers. 相似文献
998.
Background
Gap junctions (GJs) are the principal membrane structures that conduct electrical impulses between cardiac myocytes while interstitial collagen (IC) can physically separate adjacent myocytes and limit cell-cell communication. Emerging evidence suggests that both GJ and interstitial structural remodeling are linked to cardiac arrhythmia development. However, automated quantitative identification of GJ distribution and IC deposition from microscopic histological images has proven to be challenging. Such quantification is required to improve the understanding of functional consequences of GJ and structural remodeling in cardiac electrophysiology studies.Methods and Results
Separate approaches were employed for GJ and IC identification in images from histologically stained tissue sections obtained from rabbit and human atria. For GJ identification, we recognized N-Cadherin (N-Cad) as part of the gap junction connexin 43 (Cx43) molecular complex. Because N-Cad anchors Cx43 on intercalated discs (ID) to form functional GJ channels on cell membranes, we computationally dilated N-Cad pixels to create N-Cad units that covered all ID-associated Cx43 pixels on Cx43/N-Cad double immunostained confocal images. This approach allowed segmentation between ID-associated and non-ID-associated Cx43. Additionally, use of N-Cad as a unique internal reference with Z-stack layer-by-layer confocal images potentially limits sample processing related artifacts in Cx43 quantification. For IC quantification, color map thresholding of Masson''s Trichrome blue stained sections allowed straightforward and automated segmentation of collagen from non-collagen pixels. Our results strongly demonstrate that the two novel image-processing approaches can minimize potential overestimation or underestimation of gap junction and structural remodeling in healthy and pathological hearts. The results of using the two novel methods will significantly improve our understanding of the molecular and structural remodeling associated functional changes in cardiac arrhythmia development in aged and diseased hearts. 相似文献999.
1000.
Takuji Kawamura Shigeru Miyagawa Satsuki Fukushima Akira Yoshida Noriyuki Kashiyama Ai Kawamura Emiko Ito Atsuhiro Saito Akira Maeda Hiroshi Eguchi Koichi Toda Jong-Kook Lee Shuji Miyagawa Yoshiki Sawa 《PloS one》2014,9(10)
Cell surface glycans vary widely, depending on cell properties. We hypothesized that glycan expression on induced pluripotent stem cells (iPSCs) might change during cardiomyogenic differentiation toward the myocardial phenotype. N-glycans were isolated from iPSCs, iPSC-derived cardiomyocytes (iPSC-CM), and original C57BL/6 mouse myocardium (Heart). Their structures were analyzed by a mapping technique based on HPLC elution times and MALDI-TOF/MS spectra. Sixty-eight different N-glycans were isolated; the structures of 60 of these N-glycans were identified. The quantity of high-mannose type (immature) N-glycans on the iPSCs decreased with cardiomyogenic differentiation, but did not reach the low levels observed in the heart. We observed a similar reduction in neutral N-glycans and an increase in fucosylated or sialyl N-glycans. Some structural differences were detected between iPSC-CM and Heart. No N-glycolyl neuraminic acid (NeuGc) structures were detected in iPSC-CM, whereas the heart contained numerous NeuGc structures, corresponding to the expression of cytidine monophosphate-N-acetylneuraminic acid hydroxylase. Furthermore, several glycans containing Galα1-6 Gal, rarely identified in the other cells, were detected in the iPSC-CM. The expression of N-glycan on murine iPSCs changed toward the myocardial phenotype during cardiomyogenic differentiation, leaving the structural differences of NeuGc content or Galα1-6 Gal structures. Further studies will be warranted to reveal the meaning of the difference of N-glycans between the iPSC-CM and the myocardium. 相似文献