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121.
Kiyoshi Migita Toru Arai Naoki Ishizuka Yuka Jiuchi Yasuharu Sasaki Yasumori Izumi Tetsuyuki Kiyokawa Eiichi Suematsu Tomoya Miyamura Hiroshi Tsutani Yojiro Kawabe Ryutaro Matsumura Shunsuke Mori Shiro Ohshima Shigeru Yoshizawa Kenji Kawakami Yasuo Suenaga Hideo Nishimura Toyohiko Sugimoto Hiroaki Iwase Hideyuki Sawada Haruhiro Yamashita Shigeyuki Kuratsu Fumitaka Ogushi Masaharu Kawabata Toshihiro Matsui Hiroshi Furukawa Seiji Bito Shigeto Tohma 《PloS one》2013,8(11)
Background/Aims
The Japanese National Hospital Organization evidence-based medicine (EBM) Study group for Adverse effects of Corticosteroid therapy (J-NHOSAC) is a Japanese hospital-based cohort study investigating the safety of the initial use of glucocorticoids (GCs) in patients with newly diagnosed autoimmune diseases. Using the J-NHOSAC registry, the purpose of this observational study is to analyse the rates, characteristics and associated risk factors of intracellular infections in patients with newly diagnosed autoimmune diseases who were initially treated with GCs.Methodology/Principal Findings
A total 604 patients with newly diagnosed autoimmune diseases treated with GCs were enrolled in this registry between April 2007 and March 2009. Cox proportional-hazards regression was used to determine independent risk factors for serious intracellular infections with covariates including sex, age, co-morbidity, laboratory data, use of immunosuppressants and dose of GCs. Survival was analysed according to the Kaplan-Meier method and was assessed by the log-rank test. There were 127 serious infections, including 43 intracellular infections, during 1105.8 patient-years of follow-up. The 43 serious intracellular infections resulted in 8 deaths. After adjustment for covariates, diabetes (Odds ratio [OR]: 2.5, 95% confidence interval [95% CI] 1.1–5.9), lymphocytopenia (≦1000/μl, OR: 2.5, 95% CI 1.2–5.2) and use of high-dose (≧30 mg/day) GCs (OR: 2.4, 95% CI 1.1–5.3) increased the risk of intracellular infections. Survival curves showed lower intracellular infection-free survival rate in patients with diabetes, lymphocytopaenia and high-dose GCs treatments.Conclusions/Significance
Patients with newly diagnosed autoimmune diseases were at high risk of developing intracellular infection during initial treatment with GCs. Our findings provide background data on the risk of intracellular infections of patients with autoimmune diseases. Clinicians showed remain vigilant for intracellular infections in patients with autoimmune diseases who are treated with GCs. 相似文献122.
Keisuke Kirita Genichiro Ishii Rie Matsuwaki Yuki Matsumura Shigeki Umemura Shingo Matsumoto Kiyotaka Yoh Seiji Niho Koichi Goto Hironobu Ohmatsu Yuichiro Ohe Kanji Nagai Atsushi Ochiai 《PloS one》2013,8(12)
Background
Intralymphatic tumors in the extratumoral area are considered to represent the preceding phase of lymph node metastasis. The aim of this study was to clarify the biological properties of intralymphatic tumors susceptible to the development of lymph node metastasis, with special reference to the expression of cancer initiating/stem cell (CIC/CSC) related markers in cancer cells and the number of infiltrating stromal cells.Material and Methods
Primary lung adenocarcinomas with lymphatic permeation in the extratumoral area were retrospectively examined (n = 107). We examined the expression levels of CIC/CSC related markers including ALDH1, OCT4, NANOG, SOX2 and Caveolin-1 in the intralymphatic cancer cells to evaluate their relationship to lymph node metastasis. Moreover, the number of infiltrating stromal cells expressing CD34, α-smooth muscle actin, and CD204 were also evaluated.Results
Among the intralymphatic tissues, low ALDH1 expression in cancer cells, high SOX2 expression in cancer cells, and a high number of CD204(+) macrophages were independent predictive factors for lymph node metastasis (P = 0.004, P = 0.008, and P = 0.028, respectively). Among these factors, only low ALDH1 expression in cancer cells was significantly correlated with the farther spreading of lymph node metastasis (mediastinal lymph node, pathological N2) (P = 0.046) and the metastatic lymph node ratio (metastatic/resected) (P = 0.028). On the other hand, in the primary tumors, ALDH1 expression in the cancer cells was not associated with lymph node metastasis. Intralymphatic cancer cells expressing low ALDH1 levels exhibited lower E-cadherin expression levels than cancer cells with high levels of ALDH1 expression (P = 0.015).Conclusions
Intralymphatic cancer cells expressing low levels of ALDH1 and infiltrating macrophages expressing CD204 have a critical impact on lymph node metastasis. Our study also highlighted the significance of evaluating the biological properties of intralymphatic tumors for tumor metastasis. 相似文献123.
Osamu Takase Masahiro Yoshikawa Mana Idei Junichi Hirahashi Toshiro Fujita Tsuyoshi Takato Takayuki Isagawa Genta Nagae Hirofumi Suemori Hiroyuki Aburatani Keiichi Hishikawa 《PloS one》2013,8(2)
NF-κB signaling plays an essential role in maintaining the undifferentiated state of embryonic stem (ES) cells. However, opposing roles of NF-κB have been reported in mouse and human ES cells, and the role of NF-κB in human induced pluripotent stem (iPS) cells has not yet been clarified. Here, we report the role of NF-κB signaling in maintaining the undifferentiated state of human iPS cells. Compared with differentiated cells, undifferentiated human iPS cells showed an augmentation of NF-κB activity. During differentiation induced by the removal of feeder cells and FGF2, we observed a reduction in NF-κB activity, the expression of the undifferentiation markers Oct3/4 and Nanog, and the up-regulation of the differentiated markers WT-1 and Pax-2. The specific knockdown of NF-κB signaling using p65 siRNA also reduced the expression of Oct3/4 and Nanog and up-regulated WT-1 and Pax-2 but did not change the ES-like colony formation. Our results show that the augmentation of NF-κB signaling maintains the undifferentiated state of human iPS and suggest the importance of this signaling pathway in maintenance of human iPS cells. 相似文献
124.
Why are product prices in online markets dispersed in spite of very small search costs? To address this question, we construct a unique dataset from a Japanese price comparison site, which records price quotes offered by e-retailers as well as customers’ clicks on products, which occur when they proceed to purchase the product. The novelty of our approach is that we seek to extract useful information on the source of price dispersion from the shape of price distributions rather than focusing merely on the standard deviation or the coefficient of variation of prices, as previous studies have done. We find that the distribution of prices retailers quote for a particular product at a particular point in time (divided by the lowest price) follows an exponential distribution, showing the presence of substantial price dispersion. For example, 20 percent of all retailers quote prices that are more than 50 percent higher than the lowest price. Next, comparing the probability that customers click on a retailer with a particular rank and the probability that retailers post prices at a particular rank, we show that both decline exponentially with price rank and that the exponents associated with the probabilities are quite close. This suggests that the reason why some retailers set prices at a level substantially higher than the lowest price is that they know that some customers will choose them even at that high price. Based on these findings, we hypothesize that price dispersion in online markets stems from heterogeneity in customers’ preferences over retailers; that is, customers choose a set of candidate retailers based on their preferences, which are heterogeneous across customers, and then pick a particular retailer among the candidates based on the price ranking. 相似文献
125.
Toshiaki Yamanaka Takehiko Fukuda Shiho Shirota Yachiyo Sawai Takayuki Murai Nobuya Fujita Hiroshi Hosoi 《PloS one》2013,8(12)
Objectives/Hypothesis
Metabolic syndrome (MetS) is a condition that increases the risk of coronary artery disease and cerebral infarction. We determined the prevalence of MetS in vertigo patients and clinically investigated the association between MetS and vertigo.Study Design
Case-control studyMethods
The subjects were 333 patients, including 107 males and 226 females, who presented with vertigo as a primary symptom. MetS was diagnosed according to the International Diabetes Federation definition, which is based on waist circumference, blood serum levels, and blood pressure.Results
MetS was detected in 53 (15.9%) of 333 vertigo patients, including 24 males (22.4%) and 29 females (12.8%); i.e., the frequency of MetS was significantly higher among the male patients than the female patients. The overall prevalence of MetS (15.9%) among vertigo patients did not differ from that observed among general adults in previous Japanese surveillance studies; however, MetS was significantly more common among the vertigo patients in males than general adult males. The prevalence of MetS was also examined in five types of vertigo, Concomitant MetS was noted in many males with vertebrobasilar insufficiency (VBI) and isolated vertigo of unknown etiology.Conclusion
It was suggested that MetS is involved in the development of vertigo in males. MetS might be a risk factor for vascular vertigo such as VBI in males. The high frequency of MetS among males with vertigo of unknown etiology suggested that the pathogenesis of metabolic syndrome is involved in this type of isolated vertigo. 相似文献126.
Yuki Ito Jose Luis Vela Fumiko Matsumura Hitomi Hoshino Aaron Tyznik Heeseob Lee Enrico Girardi Dirk M. Zajonc Robert Liddington Motohiro Kobayashi Xingfeng Bao Jeanna Bugaytsova Thomas Borén Rongsheng Jin Yinong Zong Peter H. Seeberger Jun Nakayama Mitchell Kronenberg Minoru Fukuda 《PloS one》2013,8(12)
Approximately 10–15% of individuals infected with Helicobacter pylori will develop ulcer disease (gastric or duodenal ulcer), while most people infected with H. pylori will be asymptomatic. The majority of infected individuals remain asymptomatic partly due to the inhibition of synthesis of cholesteryl α-glucosides in H. pylori cell wall by α1,4-GlcNAc-capped mucin O-glycans, which are expressed in the deeper portion of gastric mucosa. However, it has not been determined how cholesteryl α-glucosyltransferase (αCgT), which forms cholesteryl α-glucosides, functions in the pathogenesis of H. pylori infection. Here, we show that the activity of αCgT from H. pylori clinical isolates is highly correlated with the degree of gastric atrophy. We investigated the role of cholesteryl α-glucosides in various aspects of the immune response. Phagocytosis and activation of dendritic cells were observed at similar degrees in the presence of wild-type H. pylori or variants harboring mutant forms of αCgT showing a range of enzymatic activity. However, cholesteryl α-glucosides were recognized by invariant natural killer T (iNKT) cells, eliciting an immune response in vitro and in vivo. Following inoculation of H. pylori harboring highly active αCgT into iNKT cell-deficient (Jα18−/−) or wild-type mice, bacterial recovery significantly increased in Jα18−/− compared to wild-type mice. Moreover, cytokine production characteristic of Th1 and Th2 cells dramatically decreased in Jα18−/− compared to wild-type mice. These findings demonstrate that cholesteryl α-glucosides play critical roles in H. pylori-mediated gastric inflammation and precancerous atrophic gastritis. 相似文献
127.
Thomas Lei Naoko Yamashita Takuya Watanabe Takayuki Kawahara Tomiyasu Miyaura 《Physiologia plantarum》2020,168(1):77-87
Daphne pseudomezereum A. Gray (Dpm) appears to be the only woody species in the north temperate forest that sheds its leaves in the summer while remaining green over winter (i.e. wintergreen leaf habit). Yet, the reason for this odd leaf habit has not been explored. To this end, we examined the microclimatic settings and ecophysiological traits of Dpm and its three native congeners in a field study of eight natural populations. In addition, we conducted a common garden experiment using Dpm plants where potential carbon gain across the seasons was estimated, using actual field microclimate data. Together, these data tested the hypothesis that Dpm retained traits of an open-grown upland ancestor, unable to adapt to the deep summer shade, it survived by becoming summer dormant and wintergreen. Our hypothesis was supported by patterns of leaf ecophysiological traits and carbon gain simulations in Dpm, consistent with the energetic feasibility of a summer dormancy followed by an autumn leaf sprout. We also conclude that carbon deficit driven by low light and high respiration cost is the trigger for the leaf habit of Dpm and assert that its phenological strategy represents a rare but viable alternative strategy for persistence in the temperate understory. 相似文献
128.
129.
Satoshi Komoto Saori Fukuda Takayuki Murata Koki Taniguchi 《Microbiology and immunology》2020,64(6):401-406
A reverse genetics technology is an incredibly useful technique both for a proper understanding of different aspects of virus biology and for the generation of complementary DNA (cDNA)-derived infectious viruses, which can act as safe and effective vaccines and viral vectors. Rotaviruses (RVAs), especially human RVAs (HuRVAs), had been very refractory to this technology until very recently. Here, we describe the historical background of the development of a long-awaited HuRVA reverse genetics system, culminating in the generation of replicative HuRVAs entirely from cloned cDNAs. 相似文献
130.
Yasuda Tetsuya Mishiro Koji Kusunoki Mikio Fujiwara-Tsujii Nao Yasui Hiroe Uechi Nami Fujimura Takako Inokuchi Rika Fujita Kiwamu Kanegae Yasutada Miura Yasushi Kato Ichiro Mitsunaga Takayuki 《Applied Entomology and Zoology》2020,55(2):205-212
Applied Entomology and Zoology - To evaluate the infection risk of Anoplophora malasiaca (Thomson) (Coleoptera: Cerambycidae) in two species of Japanese pine bonsais (Japanese black pine and... 相似文献