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111.
RpoS, one of the two alternative σ factors in Borrelia burgdorferi, is tightly controlled by multiple regulators and, in turn, determines expression of many critical virulence factors. Here we show that increasing RpoS expression causes cell death. The immediate effect of increasing RpoS expression was to promote bacterial division and as a consequence result in a rapid increase in cell number before causing bacterial death. No DNA fragmentation or degradation was observed during this induced cell death. Cryo-electron microscopy showed induced cells first formed blebs, which were eventually released from dying cells. Apparently blebbing initiated cell disintegration leading to cell death. These findings led us to hypothesize that increasing RpoS expression triggers intracellular programs and/or pathways that cause spirochete death. The potential biological significance of induced cell death may help B. burgdorferi regulate its population to maintain its life cycle in nature. 相似文献
112.
Juan Chen Ye Tian Yixing Liao Shuaishuai Yang Zhuoting Li Chao He Dahong Tu Xinying Sun 《PloS one》2013,8(11)
Objective
To evaluate the effect of an improved salt-restriction spoon on the attitude of salt-restriction, the using rate of salt-restriction-spoon, the actual salt intake, and 24-hour urinary sodium excretion (24HUNa).Design
A community intervention study.Setting
Two villages in Beijing.Participants
403 local adult residents being responsible for home cooking.Intervention
Participants were randomly assigned to the intervention group or the control group. Those in the intervention group were provided with an improved salt-restriction-spoon and health education, and were informed of their actual salt intake and 24HUNa. Not any intervention was given to those in the control group.Main Outcome Measures
The scores on the variables of Health Belief Model, the using rate of salt-restriction-spoon, the actual salt intake, and 24HUNa.Analysis
Covariance analyses, Chi-square tests, Student’s t tests, and repeated measures analyses of variance.Results
After 6 months of intervention, the intervention group felt significantly less objective barriers, and got access to significantly more cues to action as compared to the control group. The using rate and the correctly using rate of salt-restriction-spoon were significantly higher in the intervention group. The daily salt intake decreased by 1.42 g in the intervention group and by 0.28 g in the control group, and repeated measures analysis of variance showed significant change over time (F = 7.044, P<0.001) and significant difference between groups by time (F = 2.589, P = 0.041). The 24HUNa decreased by 34.84 mmol in the intervention group and by 33.65 mmol in the control group, and repeated measures analysis of variance showed significant change over time (F = 14.648, P<0.001) without significant difference between groups by time (F = 0.222, P = 0.870).Conclusions
The intervention effect was acceptable, therefore, the improved salt-restriction-spoon and corresponding health education could be considered as an alternative for salt reduction strategy in China and other countries where salt intake comes mainly from home cooking. 相似文献113.
Yu-Ling Tu Su-Wei Chang Hui-Ju Tsai Li-Chen Chen Wen-I Lee Man-Chin Hua Ju-Hui Cheng Liang-Shiou Ou Kuo-Wei Yeh Jing-Long Huang Tsung-Chieh Yao for the PATCH study group 《PloS one》2013,8(11)
Background
Total serum immunoglobulin (IgE) test is usually performed to aid in the diagnosis of allergic diseases, but its reference values may vary among people of different ethnic backgrounds.Objectives
To establish reference values of total IgE in Asian children and to assess their significance in the diagnosis of atopy and allergic diseases.Study design
1321 Asian children aged 5-18 years in the Prediction of Allergies in Taiwanese CHildren (PATCH) study, a population-based cohort, were evaluated for total and specific IgE by ImmunoCAP and Phadiatop Infant, respectively.Results
Male, atopy, allergic diseases, recent symptoms of upper respiratory infection, and lower FEV1/FVC, were associated with higher total IgE levels in univariate analyses. Multivariate analysis revealed that atopy was the single most important determinant explaining 66.1% of the variability of total IgE levels in this population. The area under the receiver-operator characteristic (ROC) curve of total IgE for diagnosing atopy, asthma, rhinitis, and eczema were 0.92, 0.72, 0.70, and 0.70, respectively. The sensitivity, specificity, and positive and negative predictive values of total IgE at the optimal cutoff of 77.7 kU/L on the ROC curve for diagnosing atopy were 82.3%, 87.1%, 89.5%, and 78.6%, respectively. The corresponding values using the upper 95% CI of total IgE (164.3 kU/L) in non-atopic children were 61.2%, 95.0%, 94.3%, and 64.6%, respectively; whereas a customary cutoff (100 kU/L) provided accuracy between that of the aforementioned two cutoffs. Total IgE at the cutoff of 77.7 kU/L provided modest sensitivity and specificity (49.0%-78.3%) for diagnosing allergic diseases, but had high negative predictive values (84.2%-97.9%).Conclusions
Total serum IgE discriminates Asian children with and without atopy independent of allergic symptoms, with an optimal cutoff of 77.7 kU/L. The study confirms the insufficient diagnostic accuracy of total IgE alone to detect allergic diseases, but low total IgE levels may help exclude allergic diseases. 相似文献114.
Wei-Chien Huang Yi-Ling Hsieh Chao-Ming Hung Pei-Hsuan Chien Yu-Fong Chien Lei-Chin Chen Chih-Yen Tu Chia-Hung Chen Sheng-Chieh Hsu Yueh-Ming Lin Yun-Ju Chen 《PloS one》2013,8(12)
The multikinase inhibitor, sorafenib (Nexavar®, BAY43-9006), which inhibits both the Raf/MEK/ERK pathway and several receptor tyrosine kinases (RTKs), has shown significantly therapeutic benefits in advanced hepatocellular carcinoma (HCC). However, not all HCC patients respond to sorafenib well and new therapeutic strategies to optimize the efficacy of sorafenib are urgently required. Overexpression of breast cancer resistance protein (BCRP/ABCG2) mediates the drug-efflux of several tyrosine kinase inhibitors (TKIs) to attenuate their efficacy. This study aimed to investigate the role of BCRP/ABCG2 in the sensitivity of HCC to sorafenib. Our data showed that BCRP/ABCG2 mediated the efflux of sorafenib. Co-treatment with a BCRP/ABCG2 inhibitor greatly augmented the cytotoxicity of sorafenib in HCC cells. Similar results were also achieved by the competitive inhibitor of BCRP/ABCG2, gefitinib, in combination with sorafenib. These results suggest not only that BCRP/ABCG2 is a potential predictor for the sorafenib sensitivity in HCC, but also that blockage of BCRP/ABCG2 may be a potential strategy to increase the response of HCC cells to sorafenib. 相似文献
115.
116.
117.
Aude Cincotta Thanh Thuy Nguyen Tu Julien L. Colaux Guy Terwagne Sylvie Derenne Pascal Godefroit Robert Carleer Christelle Anquetil Johan Yans 《Palaeontology》2020,63(5):841-863
A panel of geochemical techniques is used here to investigate the taphonomy of fossil feathers preserved in association with the skeleton of the Jurassic theropod Anchiornis huxleyi. Extant feathers were analysed in parallel to test whether the soft tissues morphologically preserved in the fossil also exhibit a high degree of chemical preservation. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) indicate that clays and iron oxide pseudomorphs occur in the surrounding sediment and also reveal the preservation of melanosome-like microbodies in the fossil. Carbon gradient along a depth profile and co-occurrence of carbon and sulphur are shown in the fossil by elastic backscattering (EBS) and particle-induced x-ray emission (PIXE), which are promising techniques for the elemental analysis of fossil soft tissues. The molecular composition of modern and fossil soft tissues was assessed from micro-attenuated total reflectance fourier transform infrared spectroscopy (micro-ATR FTIR), solid-state 13C nuclear magnetic resonance (CP-MAS 13C NMR) and pyrolysis gas chromatography mass spectrometry in the presence of TMAH (TMAH-Py-GC-MS). Results indicate that the proteinaceous material that comprises the modern feathers is not present in the fossil feathers. The fossil feathers and the embedding sediment exhibit a highly aliphatic character. However, substantial differences exist between these samples, revealing that the organic matter of the fossil feathers is, at least partially, derived from original constituents of the feathers. Our results suggest that, despite the morphological preservation of Anchiornis feathers, original proteins, that is keratin, were probably not preserved in the 160-myr-old feathers. 相似文献
118.
Sen Wang Fei Zheng Meijing Zhang Jun Tu Yanping Chen Jianhua Yuan Qingchang Meng 《Phyton》2020,89(4):861-871
Endosperm mutants are critical to the studies on both starch synthesis
and metabolism and genetic improvement of starch quality in maize. In the present study, a novel maize endosperm mutant A0178 of natural variation was used
as the experimental material and identified and then characterized. Through phenotypic identification, genetic analysis, main ingredients measurement and
embryo rescue, development of genetic mapping population from A0178, the
endosperm mutant gene was located. The results showed that the mutant exhibited
extremely low germination ability as attributed to the inhibited embryo development, and amounts of sugars were accumulated in the mutant seeds and more
sugars content was detected at 23 days after pollination (DAP) in A0178 than
B73. Employing genetic linkage analysis, the mutant trait was mapped in the
bin 5.04 on chromosome 5. Sequence analysis showed that two sites of base transversion and insertion presented in the protein coding region and non-coding
region of the mutant brittle-1 (bt1), the adenylate translocator encoding gene
involved in the starch synthesis. The single base insertion in the coding region
cause frameshift mutation, early termination and lose of function of Brittle-1
(BT1). All results suggested that bt1 is a novel allelic gene and the causal gene
of this endosperm mutant, providing insights on the mechanism of endosperm formation in maize. 相似文献
119.
Radiation and Environmental Biophysics - Objective of the present study was to investigate the tolerant radiation dose of nasal mucosa by observing and analyzing patients who received... 相似文献
120.
Wu Po-Ming Lin Chih-Hao Lee Hsueh-Te Shih Hsin-I Huang Chao-Ching Tu Yi-Fang 《Neurochemical research》2020,45(11):2712-2722
Neurochemical Research - Neonatal hypoxic–ischemic encephalopathy is the most common cause of neurological disability in infancy. Superimposed inflammation may further worsen neurological... 相似文献