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51.
BackgroundTo evaluate the association between various components of body composition and overall survival of patients treated with targeted therapies for advanced renal cell carcinoma.MethodsThis retrospective study included 124 Chinese patients with advanced renal cell carcinoma who had been treated with targeted therapy from 2008 to 2012 at Fudan University Cancer Center. The L3 plane from a computed tomography scan was analyzed. Area and density were recorded as quantitative and quality measures. Univariate and multivariate Cox proportion hazard regression models were constructed to calculate the crude and adjusted hazard ratio (HR) of various components of body composition for overall survival. X-tile software was used to search for optimal cutoffs for male and female patients and the concordance index evaluated incremental changes in prognostication.ResultsAfter adjusting for age, sex and Heng risk stratification, only visceral adipose tissue index (HR 0.981, p = 0.002) and subcutaneous adipose tissue index (HR 0.987, p = 0.048) were independently associated with overall survival. Visceral adipose tissue remained a significant prognostic factor (HR 0.997, p = 0.005) when the influence of body mass index was included. Using defined cutoffs, patients with low VAT had double the death rate (p = 0.007). Visceral adipose tissue also added significant benefit to Heng risk stratification. Further exploratory analysis revealed that visceral adipose tissue may be an indicator of nutritional status in patients with advanced renal cell carcinoma.ConclusionRadiologic measurement of VAT is an independent prognostic factor for Asian patients treated with targeted therapy for advanced renal cell carcinoma.  相似文献   
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Gene Set Context Analysis (GSCA) is an open source software package to help researchers use massive amounts of publicly available gene expression data (PED) to make discoveries. Users can interactively visualize and explore gene and gene set activities in 25,000+ consistently normalized human and mouse gene expression samples representing diverse biological contexts (e.g. different cells, tissues and disease types, etc.). By providing one or multiple genes or gene sets as input and specifying a gene set activity pattern of interest, users can query the expression compendium to systematically identify biological contexts associated with the specified gene set activity pattern. In this way, researchers with new gene sets from their own experiments may discover previously unknown contexts of gene set functions and hence increase the value of their experiments. GSCA has a graphical user interface (GUI). The GUI makes the analysis convenient and customizable. Analysis results can be conveniently exported as publication quality figures and tables. GSCA is available at https://github.com/zji90/GSCA. This software significantly lowers the bar for biomedical investigators to use PED in their daily research for generating and screening hypotheses, which was previously difficult because of the complexity, heterogeneity and size of the data.  相似文献   
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Colice, Gene L., Nicholas Hill, Yan-Jie Lee, Hongkai Du,James Klinger, James C. Leiter, and Lo-Chang Ou. Exaggerated pulmonary hypertension with monocrotaline in rats susceptible tochronic mountain sickness. J. Appl.Physiol. 83(1): 25-31, 1997.Hilltop (H) strainSprague-Dawley rats are more susceptible to chronic mountain sicknessthan are the Madison (M) strain rats. It is unclear what role pulmonaryvascular remodeling, polycythemia, and hypoxia-induced vasoconstrictionplay in mediating the more severe pulmonary hypertension that developsin the H rats during chronic hypoxia. It is also unclear whether theincreased sensitivity of the H rats to chronic mountain sickness isspecific for a hypoxia effect or, instead, reflects a generalpropensity toward the development of pulmonary hypertension.Monocrotaline (MCT) causes pulmonary vascular remodeling and pulmonaryhypertension. We hypothesized that the difference in the pulmonaryvascular response to chronic hypoxia between H and M rats reflects anincreased sensitivity of the H rats to any pulmonary hypertensivestimuli. Consequently, we expected the two strains to also differ intheir susceptibility to MCT-induced pulmonary hypertension. Pulmonaryarterial pressures in conscious H and M rats were measured 3 wk after asingle dose of MCT, exposure to a simulated high altitude of 18,000 ft(barometric pressure = 380 mmHg), and administration of a single doseof saline as a placebo. The H rats had significantlyhigher pulmonary arterial pressures and right ventricular weights afterMCT and chronic hypoxia than did the M rats. The H rats also had morepulmonary vascular remodeling, i.e., greater wall thickness as apercentage of vessel diameter, after MCT and chronic hypoxia than didthe M rats. The H rats had significantly lower arterialPO2 than did the M rats after MCT,but the degree of hypoxemia was mild [arterialPO2 of 72.5 ± 0.8 (SE) Torr for Hrats vs. 77.4 ± 0.8 Torr for M rats after MCT]. The H ratshad lower arterial PCO2 and largerminute ventilation values than did the M rats after MCT. Theseventilatory differences suggest that MCT caused more severe pulmonaryvascular damage in the H rats than in the M rats. These data supportthe hypothesis that the H rats have a general propensity to developpulmonary hypertension and suggest that differences in pulmonaryvascular remodeling account for the increased susceptibility of H rats,compared with M rats, to both MCT and chronic hypoxia-induced pulmonaryhypertension.

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功能性状对环境变化敏感,在生物多样性与生态系统功能关系的研究中扮演关键角色;基于生物性状的功能多样性与生态系统过程密切相关,是了解生态系统和群落功能的关键所在。基于新薛河底栖动物3个季度的调查数据,对功能性状和功能多样性时空动态及其对环境梯度的响应进行了研究。研究结果表明10个功能性状的等级性状间均存在显著差异。空间格局上,33个等级性状中有21个在河段间差异显著,涉及10个功能性状中的9个;而在时间序列上,仅有12个等级性状于各季节间差异显著,涉及10个功能性状中的6个。功能多样性于各河段间差异显著,表现为D≥E、A≥CB;而于各季节间整体表现为差异不显著;底栖动物各功能性状之间存在一定的权衡关系;水文条件是影响研究区域底栖动物功能多样性的主要因素;功能性状及功能多样性对河流生境质量具有较好的响应性。  相似文献   
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During 2018-2019, a severe human adenovirus (HAdV) infection outbreak occurred in southern China. Here, we screened 18 respiratory pathogens in 1704 children (≤ 14 years old) hospitalized with acute respiratory illness in Guangzhou, China, in 2019. In total, 151 patients had positive HAdV test results; 34.4% (52/151) of them exhibited severe illness. HAdV infection occurred throughout the year, with a peak in summer. The median patient age was 3.0 (interquartile range:1.1-5.0) years. Patients with severe HAdV infection exhibited increases in 12 clinical indexes (P ≤ 0.019) and decreases in four indexes (P ≤ 0.007), compared with patients exhibiting nonsevere infection. No significant differences were found in age or sex distribution according to HAdV infection severity (P > 0.05); however, the distributions of comorbid disease and HAdV co-infection differed according to HAdV infection severity (P < 0.05). The main epidemic types were HAdV-3 (47.0%, 71/151) and HAdV-7 (46.4%, 70/151). However, the severe illness rate was significantly higher in patients with HAdV-7 (51.4%) than in patients with HAdV-3 (19.7%) and other types of HAdV (20%) (P < 0.001). Sequencing analysis of genomes/capsid genes of 13 HAdV-7 isolates revealed high similarity to previous Chinese isolates. A representative HAdV-7 isolate exhibited a similar proliferation curve to the curve described for the epidemic HAdV-3 strain Guangzhou01 (accession no. DQ099432) (P > 0.05); the HAdV-7 isolate exhibited stronger virulence and infectivity, compared with HAdV-3 (P < 0.001). Overall, comorbid disease, HAdV co-infection, and high virulence and infectivity of HAdV-7 were critical risk factors for severe HAdV infection; these data can facilitate treatment, control, and prevention of HAdV infection.  相似文献   
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Japonica/geng and indica/xian are two major rice (Oryza sativa) subspecies with multiple divergent traits, but how these traits are related and interact within each subspecies remains elusive. Brassinosteroids (BRs) are a class of steroid phytohormones that modulate many important agronomic traits in rice. Here, using different physiological assays, we revealed that japonica rice exhibits an overall lower BR sensitivity than indica. Extensive screening of BR signaling genes led to the identification of a set of genes distributed throughout the primary BR signaling pathway with divergent polymorphisms. Among these, we demonstrate that the C38/T variant in BR Signaling Kinase2 (OsBSK2), causing the amino acid change P13L, plays a central role in mediating differential BR signaling in japonica and indica rice. OsBSK2L13 in indica plays a greater role in BR signaling than OsBSK2P13 in japonica by affecting the auto-binding and protein accumulation of OsBSK2. Finally, we determined that OsBSK2 is involved in a number of divergent traits in japonica relative to indica rice, including grain shape, tiller number, cold adaptation, and nitrogen-use efficiency. Our study suggests that the natural variation in OsBSK2 plays a key role in the divergence of BR signaling, which underlies multiple divergent traits between japonica and indica.  相似文献   
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Botryosphaeria dothidea is a severe causal agent of die-back and cankers of many woody plants and causes great losses in many regions. The pathogenic mechanism of this pathogen has not been well explored due to lack of mutants and genetic information. In this study, we developed an Agrobacterium tumefaciens-mediated transformation (ATMT) protocol for B. dothidea protoplasts using vector pBHt2 containing the hph gene as a selection marker under the control of trp C promoter. Using this protocol we successfully generated the B. dothidea transformants with efficiency about 23 transformants per 105 protoplasts. This is the first report of genetic transformation of B. dothidea via ATMT and this protocol provides an effective tool for B. dothidea genome manipulation, gene identification and functional analysis.  相似文献   
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