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991.
Bang Wool Eom Keun Won Ryu Byung-Ho Nam Yunjin Park Hyuk-Joon Lee Min Chan Kim Gyu Seok Cho Chan Young Kim Seung Wan Ryu Dong Woo Shin Woo Jin Hyung Jun Ho Lee 《PloS one》2015,10(2)
BackgroundA small number of nomograms have been previously developed to predict the individual survival of patients who undergo curative resection for gastric cancer. However, all were derived from single high-volume centers. The aim of this study was to develop and validate a nomogram for gastric cancer patients using a multicenter database.MethodsWe reviewed the clinicopathological and survival data of 2012 patients who underwent curative resection for gastric cancer between 2001 and 2006 at eight centers. Among these centers, six institutions were randomly assigned to the development set, and the other two centers were assigned to the validation set. Multivariate analysis using the Cox proportional hazard regression model was performed, and discrimination and calibration were evaluated by external validation.ResultsMultivariate analyses revealed that age, tumor size, lymphovascular invasion, depth of invasion, and metastatic lymph nodes were significant prognostic factors for overall survival. In the external validation, the concordance index was 0.831 (95% confidence interval, 0.784–0.878), and Hosmer-Lemeshow chi-square statistic was 3.92 (P = 0.917).ConclusionsWe developed and validated a nomogram to predict 5-year overall survival after curative resection for gastric cancer based on a multicenter database. This nomogram can be broadly applied even in general hospitals and is useful for counseling patients, and scheduling follow-up. 相似文献
992.
Shiho Hayakawa Yasuharu Takaku Jung Shan Hwang Takeo Horiguchi Hiroshi Suga Walter Gehring Kazuho Ikeo Takashi Gojobori 《PloS one》2015,10(3)
The ocelloid is an extraordinary eyespot organelle found only in the dinoflagellate family Warnowiaceae. It contains retina- and lens-like structures called the retinal body and the hyalosome. The ocelloid has been an evolutionary enigma because of its remarkable resemblance to the multicellular camera-type eye. To determine if the ocelloid is functionally photoreceptive, we investigated the warnowiid dinoflagellate Erythropsidinium. Here, we show that the morphology of the retinal body changed depending on different illumination conditions and the hyalosome manifests the refractile nature. Identifying a rhodopsin gene fragment in Erythropsidinium ESTs that is expressed in the retinal body by in situ hybridization, we also show that ocelloids are actually light sensitive photoreceptors. The rhodopsin gene identified is most closely related to bacterial rhodopsins. Taken together, we suggest that the ocelloid is an intracellular camera-type eye, which might be originated from endosymbiotic origin. 相似文献
993.
Non-selective effects, like genetic drift, are an important factor in modern conceptions of evolution, and have been extensively studied for constant population sizes (Kimura, 1955; Otto and Whitlock, 1997). Here, we consider non-selective evolution in the case of growing populations that are of small size and have varying trait compositions (e.g. after a population bottleneck). We find that, in these conditions, populations never fixate to a trait, but tend to a random limit composition, and that the distribution of compositions “freezes” to a steady state. This final state is crucially influenced by the initial conditions. We obtain these findings from a combined theoretical and experimental approach, using multiple mixed subpopulations of two Pseudomonas putida strains in non-selective growth conditions (Matthijs et al, 2009) as model system. The experimental results for the population dynamics match the theoretical predictions based on the Pólya urn model (Eggenberger and Pólya, 1923) for all analyzed parameter regimes. In summary, we show that exponential growth stops genetic drift. This result contrasts with previous theoretical analyses of non-selective evolution (e.g. genetic drift), which investigated how traits spread and eventually take over populations (fixate) (Kimura, 1955; Otto and Whitlock, 1997). Moreover, our work highlights how deeply growth influences non-selective evolution, and how it plays a key role in maintaining genetic variability. Consequently, it is of particular importance in life-cycles models (Melbinger et al, 2010; Cremer et al, 2011; Cremer et al, 2012) of periodically shrinking and expanding populations. 相似文献
994.
Xiaoyun Zhou Linzhi Li Jianhua Xiang Guofu Gao Faxi Xu Ailing Liu Xianwen Zhang Yan Peng Xinbo Chen Xiangyuan Wan 《PloS one》2015,10(1)
Cuticular wax covers aerial organs of plants and functions as the outermost barrier against non-stomatal water loss. We reported here the functional characterization of the Glossy1(GL1)-homologous gene OsGL1-3 in rice using overexpression and RNAi transgenic rice plants. OsGL1-3 gene was ubiquitously expressed at different level in rice plants except root and its expression was up-regulated under ABA and PEG treatments. The transient expression of OsGL1-3–GFP fusion protein indicated that OsGL1-3 is mainly localized in the plasma membrane. Compared to the wild type, overexpression rice plants exhibited stunted growth, more wax crystallization on leaf surface, and significantly increased total cuticular wax load due to the prominent changes of C30–C32 aldehydes and C30 primary alcohols. While the RNAi knockdown mutant of OsGL1-3 exhibited no significant difference in plant height, but less wax crystallization and decreased total cuticular wax accumulation on leaf surface. All these evidences, together with the effects of OsGL1-3 on the expression of some wax synthesis related genes, suggest that OsGL1-3 is involved in cuticular wax biosynthesis. Overexpression of OsGL1-3 decreased chlorophyll leaching and water loss rate whereas increased tolerance to water deficit at both seedling and late-tillering stages, suggesting an important role of OsGL1-3 in drought tolerance. 相似文献
995.
Geon Ha Kim Seun Jeon Kiho Im Hunki Kwon Byung Hwa Lee Ga Young Kim Hana Jeong Noh Eul Han Sang Won Seo Hanna Cho Young Noh Sang Eon Park Hojeong Kim Jung Won Hwang Cindy W. Yoon Hee Jin Kim Byoung Seok Ye Ju Hee Chin Jung-Hyun Kim Mee Kyung Suh Jong Min Lee Sung Tae Kim Mun-Taek Choi Mun Sang Kim Kenneth M Heilman Jee Hyang Jeong Duk L. Na 《PloS one》2015,10(4)
The purpose of this study was to investigate if multi-domain cognitive training, especially robot-assisted training, alters cortical thickness in the brains of elderly participants. A controlled trial was conducted with 85 volunteers without cognitive impairment who were 60 years old or older. Participants were first randomized into two groups. One group consisted of 48 participants who would receive cognitive training and 37 who would not receive training. The cognitive training group was randomly divided into two groups, 24 who received traditional cognitive training and 24 who received robot-assisted cognitive training. The training for both groups consisted of daily 90-min-session, five days a week for a total of 12 weeks. The primary outcome was the changes in cortical thickness. When compared to the control group, both groups who underwent cognitive training demonstrated attenuation of age related cortical thinning in the frontotemporal association cortices. When the robot and the traditional interventions were directly compared, the robot group showed less cortical thinning in the anterior cingulate cortices. Our results suggest that cognitive training can mitigate age-associated structural brain changes in the elderly.
Trial Registration
ClnicalTrials.gov NCT01596205 相似文献996.
Ke Wan Jianxun Zhao Hao Huang Qing Zhang Xi Chen Zhi Zeng Li Zhang Yucheng Chen 《PloS one》2015,10(4)
Aims
High triglycerides (TG) and low high-density lipoprotein cholesterol (HDL-C) are cardiovascular risk factors. A positive correlation between elevated TG/HDL-C ratio and all-cause mortality and cardiovascular events exists in women. However, utility of TG to HDL-C ratio for prediction is unknown among acute coronary syndrome (ACS).Methods
Fasting lipid profiles, detailed demographic data, and clinical data were obtained at baseline from 416 patients with ACS after coronary revascularization. Subjects were stratified into three levels of TG/HDL-C. We constructed multivariate Cox-proportional hazard models for all-cause mortality over a median follow-up of 3 years using log TG to HDL-C ratio as a predictor variable and analyzing traditional cardiovascular risk factors. We constructed a logistic regression model for major adverse cardiovascular events (MACEs) to prove that the TG/HDL-C ratio is a risk factor.Results
The subject’s mean age was 64 ± 11 years; 54.5% were hypertensive, 21.8% diabetic, and 61.0% current or prior smokers. TG/HDL-C ratio ranged from 0.27 to 14.33. During the follow-up period, there were 43 deaths. In multivariate Cox models after adjusting for age, smoking, hypertension, diabetes, and severity of angiographic coronary disease, patients in the highest tertile of ACS had a 5.32-fold increased risk of mortality compared with the lowest tertile. After adjusting for conventional coronary heart disease risk factors by the logistic regression model, the TG/HDL-C ratio was associated with MACEs.Conclusion
The TG to HDL-C ratio is a powerful independent predictor of all-cause mortality and is a risk factor of cardiovascular events. 相似文献997.
Background
Inhibition and eradication of Staphylococcus aureus biofilms with conventional antibiotic is difficult, and the treatment is further complicated by the rise of antibiotic resistance among staphylococci. Consequently, there is a need for novel antimicrobials that can treat biofilm-related infections and decrease antibiotics burden. Natural compounds such as eugenol with anti-microbial properties are attractive agents that could reduce the use of conventional antibiotics. In this study we evaluated the effect of eugenol on MRSA and MSSA biofilms in vitro and bacterial colonization in vivo.Methods and Results
Effect of eugenol on in vitro biofilm and in vivo colonization were studied using microtiter plate assay and otitis media-rat model respectively. The architecture of in vitro biofilms and in vivo colonization of bacteria was viewed with SEM. Real-time RT-PCR was used to study gene expression. Check board method was used to study the synergistic effects of eugenol and carvacrol on established biofilms. Eugenol significantly inhibited biofilms growth of MRSA and MSSA in vitro in a concentration-dependent manner. Eugenol at MIC or 2×MIC effectively eradicated the pre-established biofilms of MRSA and MSSA clinical strains. In vivo, sub-MIC of eugenol significantly decreased 88% S. aureus colonization in rat middle ear. Eugenol was observed to damage the cell-membrane and cause a leakage of the cell contents. At sub-inhibitory concentration, it decreases the expression of biofilm-and enterotoxin-related genes. Eugenol showed a synergistic effect with carvacrol on the eradication of pre-established biofilms.Conclusion/Major Finding
This study demonstrated that eugenol exhibits notable activity against MRSA and MSSA clinical strains biofilms. Eugenol inhibited biofilm formation, disrupted the cell-to-cell connections, detached the existing biofilms, and killed the bacteria in biofilms of both MRSA and MSSA with equal effectiveness. Therefore, eugenol may be used to control or eradicate S. aureus biofilm-related infections. 相似文献998.
Eun Joo Yang Seung Yeol Lee Keewon Kim Se Hee Jung Soong-Nang Jang Soo Jeong Han Wan-Ho Kim Jae-Young Lim 《PloS one》2015,10(6)
The purpose of this study is to assess health-related quality of life in polio survivors (PS) compared with that in the general population in Korea. Polio survivors (n = 120) from outpatient clinics at two hospitals, healthy controls (HC, n = 121) and members of the general population with activity limitations (AL, n = 121) recruited through a proportional-allocation, systematic sampling strategy from the Fourth Korean National Health and Nutrition Examination Survey were surveyed with self-rated health-related quality of life (Euro QoL five-dimensions). The proportion of participants who reported problems in mobility, usual activity, and symptoms of anxiety/depression were higher in the PS group compared with the HC and AL groups. There was no significant difference in the self-care dimension across the groups. Polio-specific questionnaire, pain, depression, fatigue, Modified Barthel Index (K-MBI) and Short Physical Performance Battery (SPPB) were assessed in the PS group. Those with post-poliomyelitis syndrome had greater problems in mobility, usual activity, and depression/anxiety. Polio survivors, especially those with more pain and fatigue symptoms, and those who did not have access to medical services had poorer health-related quality of life. These findings afford useful information for potential intervention improving quality of life in polio survivors. 相似文献
999.
Zhihong Wan Yichen Wu Jing Yi Shaoli You Hongling Liu Zhiqiang Sun Bing Zhu Hong Zang Chen Li Fangfang Liu Dongze Li Yuanli Mao Shaojie Xin 《PloS one》2015,10(1)
Background & Aims
HBV-related acute-on-chronic liver failure (HBV-ACLF) is a severe liver disease which results in a high mortality in China. To early predict the prognosis of the patients may prevent the complications and improve the survival. This study was aimed to develop a new prognostic index to estimate the survival related to HBV-ACLF.Methods
Consecutive patients with HBV-ACLF were included in a prospective observational study. Serum Cystatin C concentrations were measured by using the particle-enhanced immunonephelometry assay. All of the patients were followed for at least 3 months. Cox regression analysis was carried out to identify which factors were predictive of mortality. The area under the receiver operating characteristic curve (AUC) was used to evaluate the efficacy of the variates for early predicting mortality.Results
Seventy-two patients with HBV-ACLF were recruited between January 2012 and January 2013. Thirty patients died (41.7%) during 3-months followed up. Cox multivariate regression analysis identified serum cystatin C (CysC) and total bilirubin (TBil) were independent factors significantly (P < 0.01) associated with survival. Our results further showed that new prognostic index (PI) combining serum CysC with TBil was a good indicator for predicting the mortality of patients with HBV-ACLF. Specifically, the PI had a higher accuracy than the CTP, MELD, or MELD-Na scoring for early prediction short-term survival of HBV-ACLF patients with normal levels of serum creatinine (Cr). The survival rate in low risk group (PI < 3.91) was 94.3%, which was markedly higher than those in the high-risk group (PI ≥ 3.91) (17.4%, P < 0.001).Conclusion
We developed a new prognostic index combining serum CysC with TBil which early predicted the short-term mortality of HBV-ACLF patients. 相似文献1000.
Jaewon Shim Hee Jin Son Yiseul Kim Ki Hwa Kim Jung Tae Kim Hana Moon Min Jung Kim Takumi Misaka Mee-Ra Rhyu 《PloS one》2015,10(4)
Although the five basic taste qualities—sweet, sour, bitter, salty and umami—can be recognized by the respective gustatory system, interactions between these taste qualities are often experienced when food is consumed. Specifically, the umami taste has been investigated in terms of whether it enhances or reduces the other taste modalities. These studies, however, are based on individual perception and not on a molecular level. In this study we investigated umami-sweet taste interactions using umami compounds including monosodium glutamate (MSG), 5’-mononucleotides and glutamyl-dipeptides, glutamate-glutamate (Glu-Glu) and glutamate-aspartic acid (Glu-Asp), in human sweet taste receptor hT1R2/hT1R3-expressing cells. The sensitivity of sucrose to hT1R2/hT1R3 was significantly attenuated by MSG and umami active peptides but not by umami active nucleotides. Inhibition of sweet receptor activation by MSG and glutamyl peptides is obvious when sweet receptors are activated by sweeteners that target the extracellular domain (ECD) of T1R2, such as sucrose and acesulfame K, but not by cyclamate, which interact with the T1R3 transmembrane domain (TMD). Application of umami compounds with lactisole, inhibitory drugs that target T1R3, exerted a more severe inhibitory effect. The inhibition was also observed with F778A sweet receptor mutant, which have the defect in function of T1R3 TMD. These results suggest that umami peptides affect sweet taste receptors and this interaction prevents sweet receptor agonists from binding to the T1R2 ECD in an allosteric manner, not to the T1R3. This is the first report to define the interaction between umami and sweet taste receptors. 相似文献