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991.
The nutritional quality of host plants is an important determinant of fitness in insect herbivores. However, it remains an open question whether the ingestion of a particular plant will have the same effects on an herbivore under differing thermal conditions. We measured the performance of the generalist‐feeding caterpillars of Hyphantria cunea Drury (Lepidoptera: Arctiidae) raised on one of five natural host plants to determine their nutritional quality: Platanus occidentalis L. (Platanaceae), Sophora japonica (L.) Schott (Fabaceae), Prunus × yedoensis Matsum. (Rosaceae), Cornus kousa Hance (Cornaceae), or Betula platyphylla Sukaczev (Betulaceae). Caterpillars performed well on P. occidentalis, S. japonica, and P. × yedoensis, but poorly on C. kousa and B. platyphylla. The nutritional phenotype of caterpillars varied among host–plant groups, with the proportion of lipid‐free body mass to lipid content being higher for caterpillars raised on P. occidentalis and S. japonica (3.8–4.2:1) than for caterpillars raised on P. × yedoensis (1.6–2.1:1). A multi‐factorial experimental design was employed to investigate the interactive effects of host–plant quality and temperature on the performance of H. cunea caterpillars raised on either P. occidentalis or P. × yedoensis at three rearing temperatures (20, 25, or 30 °C). Caterpillars raised on P. occidentalis displayed a monotonic decrease in development time with increasing temperature, but the development time of those on P. × yedoensis decreased rapidly as temperature rose from 20 to 25 °C and then stayed unchanged despite further increase in temperature. The rate at which body size increased with decreasing temperature was much steeper for caterpillars raised on P. occidentalis than for those on P. × yedoensis. Collectively, these results indicate that host plant can alter the thermal reaction norms for the key life‐history traits of herbivores. This study has implications for understanding the impacts of climate change on herbivore–plant interactions.  相似文献   
992.
Cationic membrane-proximal amino acids determine the topology of membrane proteins by interacting with anionic lipids that are restricted to the intracellular membrane leaflet. This mechanism implies that anionic lipids interfere with electrostatic interactions of membrane proteins. The integrin αIIbβ3 transmembrane (TM) complex is stabilized by a membrane-proximal αIIb(Arg995)-β3(Asp723) interaction; here, we examine the influence of anionic lipids on this complex. Anionic lipids compete for αIIb(Arg995) contacts with β3(Asp723) but paradoxically do not diminish the contribution of αIIb(Arg995)-β3(Asp723) to TM complex stability. Overall, anionic lipids in annular positions stabilize the αIIbβ3 TM complex by up to 0.50 ± 0.02 kcal/mol relative to zwitterionic lipids in a headgroup structure-dependent manner. Comparatively, integrin receptor activation requires TM complex destabilization of 1.5 ± 0.2 kcal/mol, revealing a sizeable influence of lipid composition on TM complex stability. We implicate changes in lipid headgroup accessibility to small molecules (physical membrane characteristics) and specific but dynamic protein-lipid contacts in this TM helix-helix stabilization. Thus, anionic lipids in ubiquitous annular positions can benefit the stability of membrane proteins while leaving membrane-proximal electrostatic interactions intact.  相似文献   
993.

Background

There is sparse evidence that demonstrates the association between macro-environmental processes and drug-related HIV epidemics. The present study explores the relationship between economic, socio-economic, policy and structural indicators, and increases in reported HIV infections among people who inject drugs (PWID) in the European Economic Area (EEA).

Methods

We used panel data (2003–2012) for 30 EEA countries. Statistical analyses included logistic regression models. The dependent variable was taking value 1 if there was an outbreak (significant increase in the national rate of HIV diagnoses in PWID) and 0 otherwise. Explanatory variables included the growth rate of Gross Domestic Product (GDP), the share of the population that is at risk for poverty, the unemployment rate, the Eurostat S80/S20 ratio, the Gini coefficient, the per capita government expenditure on health and social protection, and variables on drug control policy and drug-using population sizes. Lags of one to three years were investigated.

Findings

In multivariable analyses, using two-year lagged values, we found that a 1% increase of GDP was associated with approximately 30% reduction in the odds of an HIV outbreak. In GDP-adjusted analyses with three-year lagged values, the effect of the national income inequality on the likelihood of an HIV outbreak was significant [S80/S20 Odds Ratio (OR) = 3.89; 95% Confidence Interval (CI): 1.15 to 13.13]. Generally, the multivariable analyses produced similar results across three time lags tested.

Interpretation

Given the limitations of ecological research, we found that declining economic growth and increasing national income inequality were associated with an elevated probability of a large increase in the number of HIV diagnoses among PWID in EEA countries during the last decade. HIV prevention may be more effective if developed within national and European-level policy contexts that promote income equality, especially among vulnerable groups.  相似文献   
994.

Background

The effectiveness of the 2011–2012 seasonal influenza vaccine was evaluated in adult Korean populations with regard to how well it could prevent laboratory-confirmed influenza and influenza-related complications.

Materials and Methods

A retrospective case-control and retrospective cohort study was conducted among patients who visited four selected hospitals from September 2011 to May 2012. The analysis included 1,130 laboratory-confirmed influenza patients. For each influenza case, one control patient was chosen at a ratio of 1:1. A control was defined as an age group-matched patient who visited the same hospital with influenza-like illness within 48 hours of symptom onset but for whom laboratory tests were negative for influenza. Age group and visit date were matched between the cases and controls. Vaccine effectiveness (VE) was defined as [100 × (1-odds ratio for influenza in vaccinated versus non-vaccinated persons)]. The patients with laboratory-confirmed influenza were followed for at least one month through reviewing the medical records and conducting a telephone interview.

Results

The VE of the 2011–2012 seasonal influenza vaccine was 3.8% [95% confidence interval (CI), -16.5% to 20.6%] for preventing laboratory-confirmed influenza, -16.1% (95% CI, -48.3 to 9.1) for influenza A and 26.2% (95% CI, -2.6 to 46.2) for influenza B. The age-specific adjusted VE was 0.3% (95% CI, -29.4 to 23.1) among participants aged 19 to 49 years, 11.9% (95% CI, -34.3 to 42.2) among those aged 50 to 64 years and -3.9% (-60.1 to 32.5) among those aged ≥65 years. The adjusted VE for preventing any influenza-related complications was -10.7% (95% CI, -41.1% to 42.2%).

Conclusions

The 2011–2012 seasonal influenza vaccine was not effective in preventing laboratory-confirmed influenza or influenza-related complications in adult Korean populations.  相似文献   
995.

Objectives

Complicated intra-abdominal infection (cIAI) is infection that extends beyond the hollow viscus of origin into the peritoneal space, and is associated with either abscess formation or peritonitis. There are few studies that have assessed the actual costs and outcomes associated with failure of initial antibiotic therapy for cIAI. The aims of this study were to evaluate risk factors and impact on costs and outcomes of failure of initial antibiotic therapy for community-onset cIAI.

Methods

A retrospective study was performed at eleven tertiary-care hospitals. Hospitalized adults with community-onset cIAI who underwent an appropriate source control procedure between August 2008 and September 2011 were included. Failure of initial antibiotic therapy was defined as a change of antibiotics due to a lack of improvement of the clinical symptoms and signs associated with cIAI in the first week.

Results

A total of 514 patients hospitalized for community-onset cIAI were included in the analysis. The mean age of the patients was 53.3 ± 17.6 years, 72 patients (14%) had health care-associated infection, and 48 (9%) experienced failure of initial antibiotic therapy. Failure of initial antibiotic therapy was associated with increased costs and morbidity. After adjustment for covariates, patients with unsuccessful initial therapy received an additional 2.9 days of parenteral antibiotic therapy, were hospitalized for an additional 5.3 days, and incurred $3,287 in additional inpatient charges. Independent risk factors for failure of initial antibiotic therapy were health care-associated infection, solid cancer, and APACHE II ≥13.

Conclusions

To improve outcomes and costs in patients with community-onset cIAI, rapid assessment of health care-associated risk factors and severity of disease, selection of an appropriate antibiotic regimen accordingly, and early infection source control should be performed.  相似文献   
996.
997.
BackgroundSelf-agency (SA) is a person’s feeling that his action was generated by himself. The neural substrates of SA have been investigated in many neuroimaging studies, but the functional connectivity of identified regions has rarely been investigated. The goal of this study is to investigate the neural network related to SA.MethodsSA of hand movements was modulated with virtual reality. We examined the cortical network relating to SA modulation with electroencephalography (EEG) power spectrum and phase coherence of alpha, beta, and gamma frequency bands in 16 right-handed, healthy volunteers.ResultsIn the alpha band, significant relative power changes and phase coherence of alpha band were associated with SA modulation. The relative power decrease over the central, bilateral parietal, and right temporal regions (C4, Pz, P3, P4, T6) became larger as participants more effectively controlled the virtual hand movements. The phase coherence of the alpha band within frontal areas (F7-FP2, F7-Fz) was directly related to changes in SA. The functional connectivity was lower as the participants felt that they could control their virtual hand. In the other frequency bands, significant phase coherences were observed in the frontal (or central) to parietal, temporal, and occipital regions during SA modulation (Fz-O1, F3-O1, Cz-O1, C3-T4L in beta band; FP1-T6, FP1-O2, F7-T4L, F8-Cz in gamma band).ConclusionsOur study suggests that alpha band activity may be the main neural oscillation of SA, which suggests that the neural network within the anterior frontal area may be important in the generation of SA.  相似文献   
998.

Objective

To investigate the difference between preoperative radiologic tumor volume (RTV) and postoperative pathologic tumor volume (PTV) in patients who received nephrectomy for renal cell carcinoma (RCC).

Materials and Methods

We reviewed 482 patients who underwent preoperative computed tomography (CT) within 4 weeks before radical or partial nephrectomy for renal cell carcinoma. RTV measured by a three dimensional rendering program was compared with PTV (π/6ⅹheightⅹlengthⅹwidth) measured in surgical specimen according to pathologic tumor size and histologic subtype. Correlation of the inter-quartile range (IQR) of the RTV and Fuhrman nuclear grade was also investigated.

Results

There was a significant positive linear correlation between RTV and PTV (p<0.001, r = 0.911), and the mean RTV and mean PTV were not significantly different (79.0 vs 76.9cm3, p = 0.393). For pathologic tumor size (PTS) <4cm, the mean RTV was larger than the mean PTV (10.9 vs 7.1cm3, p<0.001). For a PTS of 4-7cm, the mean RTV was larger than the mean PTV (56.0 vs 44.7cm3, p<0.001). However, for a PTS ≥7cm, there was no statistical difference between RTV and PTV (p>0.05). Among patients with clear cell RCC, the mean RTV was significantly larger than the mean PTV (p = 0.042), not for non-clear cell group (p = 0.055). As the quartile of the RTV increased, the Fuhrman grade also increased (p<0.001).

Conclusions

RTV was correlated with PTV and pathologic grade. RTV was larger than the PTV for a tumor size 7 cm or less or in clear cell RCC. RTV may be useful to measure tumor burden preoperatively.  相似文献   
999.
Development of natural killer cells from hematopoietic stem cells   总被引:1,自引:0,他引:1  
  相似文献   
1000.
Protein phosphorylation is one of the major mechanisms by which eukaryotic cells transduce extracellular signals into intracellular responses. Calcium/calmodulin (Ca(2+)/CaM)-dependent protein phosphorylation has been implicated in various cellular processes, yet little is known about Ca(2+)/CaM-dependent protein kinases (CaMKs) in plants. From an Arabidopsis expression library screen using a horseradish peroxidase-conjugated soybean calmodulin isoform (SCaM-1) as a probe, we isolated a full-length cDNA clone that encodes AtCK (Arabidopsis thaliana calcium/calmodulin-dependent protein kinase). The predicted structure of AtCK contains a serine/threonine protein kinase catalytic domain followed by a putative calmodulin-binding domain and a putative Ca(2+)-binding domain. Recombinant AtCK was expressed in E. coli and bound to calmodulin in a Ca(2+)-dependent manner. The ability of CaM to bind to AtCK was confirmed by gel mobility shift and competition assays. AtCK exhibited its highest levels of autophosphorylation in the presence of 3 mM Mn(2+). The phosphorylation of myelin basic protein (MBP) by AtCK was enhanced when AtCK was under the control of calcium-bound CaM, as previously observed for other Ca(2+)/CaM-dependent protein kinases. In contrast to maize and tobacco CCaMKs (calcium and Ca(2+)/CaM-dependent protein kinase), increasing the concentration of calmodulin to more than 3 microgram suppressed the phosphorylation activity of AtCK. Taken together our results indicate that AtCK is a novel Arabidopsis Ca(2+)/CaM-dependent protein kinase which is presumably involved in CaM-mediated signaling.  相似文献   
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