Satellite-Detected Contrasting Responses of Canopy Structure and Leaf Physiology to Drought

Disentangling drought impacts on plant photosynthesis is crucial for projecting future terrestrial carbon dynamics. We examined the separate responses of canopy structure and leaf physiology to an extreme summer drought that occurred in 2011 over Southwest China, where the weather was humid and radiation was the main growth-limiting factor. Canopy structure and leaf physiology were, respectively, represented by near-infrared reflectance of vegetation (NIRv) derived from MODIS data and leaf scale fluorescence yield (Φf) derived from both continuous SIF (CSIF) and global OCO-2 SIF (GOSIF). We detected contrasting responses of canopy structure and leaf physiology to drought with a 14.0% increase in NIRv, compared with 12.6 or 19.3% decreases in Φf from CSIF and GOSIF, respectively. The increase in structure resulted in a slight carbon change, due to water deficit-induced physiological constraints. The net ecosystem effect was a 7.5% (CSIF), 1.2% (GOSIF), and-2.96% (EC-LUE GPP) change in photosynthesis. Our study improves understanding of complex vegetation responses of plant photosynthesis to drought and may contribute to the reconciliation of contrasting observed directions in plant responses to drought in cloudy regions via remote sensing

Relationship Between Stressful Life Events and Sleep Quality: Rumination as a Mediator and Resilience as a Moderator

Purpose: The aim of this study was to investigate the relationship between stressful life events and sleep quality and to probe the role of rumination and resilience in the relationship.Method: The Adolescent Self-Rating Life Events Checklist, Ruminative Responses Scale, Connor–Davidson Resilience Scale, and Pittsburgh Sleep Quality Index were used among 1,065 college students. Statistical Product and Service Solutions (SPSS) 20.0 and the SPSS macro Process, which were specifically developed for assessing complex models including both mediators and moderators, were used to analyze the data.Results: High scores of stressful life events predicted worse sleep quality. Rumination partially mediated the relations between stressful life events and sleep quality. Resilience moderated the direct and indirect paths leading from stressful life events to sleep quality.Conclusions: The results demonstrate that stressful life events can directly affect the sleep quality of college students and indirectly through rumination. Additionally, increasing psychological resilience could decrease both the direct effect and the indirect effect of stressful life events affecting sleep quality. The results of this study may contribute to a better understanding of the effects, as well as the paths and conditions, of stressful life events on sleep quality in college students. Moreover, these findings can provide constructive suggestions for improving college students’ sleep quality

Control of neutrophil influx during peritonitis by transcriptional cross‐regulation of chemokine CXCL1 by IL‐17 and IFN‐γ

Neutrophil infiltration is a hallmark of peritoneal inflammation, but mechanisms regulating neutrophil recruitment in patients with peritoneal dialysis (PD)-related peritonitis are not fully defined. We examined 104 samples of PD effluent collected during acute peritonitis for correspondence between a broad range of soluble parameters and neutrophil counts. We observed an association between peritoneal IL-17 and neutrophil levels. This relationship was evident in effluent samples with low but not high IFN-γ levels, suggesting a differential effect of IFN-γ concentration on neutrophil infiltration. Surprisingly, there was no association of neutrophil numbers with the level of CXCL1, a key IL-17-induced neutrophil chemoattractant. We investigated therefore the production of CXCL1 by human peritoneal mesothelial cells (HPMCs) under in vitro conditions mimicking clinical peritonitis. Stimulation of HPMCs with IL-17 increased CXCL1 production through induction of transcription factor SP1 and activation of the SP1-binding region of the CXCL1 promoter. These effects were amplified by TNFα. In contrast, IFN-γ dose-dependently suppressed IL-17-induced SP1 activation and CXCL1 production through a transcriptional mechanism involving STAT1. The SP1-mediated induction of CXCL1 was also observed in HPMCs exposed to PD effluent collected during peritonitis and containing IL-17 and TNFα, but not IFN-γ. Supplementation of the effluent with IFN-γ led to a dose-dependent activation of STAT1 and a resultant inhibition of SP1-induced CXCL1 expression. Transmesothelial migration of neutrophils in vitro increased upon stimulation of HPMCs with IL-17 and was reduced by IFN-γ. In addition, HPMCs were capable of binding CXCL1 at their apical cell surface. These observations indicate that changes in relative peritoneal concentrations of IL-17 and IFN-γ can differently engage SP1–STAT1, impacting on mesothelial cell transcription of CXCL1, whose release and binding to HPMC surface may determine optimal neutrophil recruitment and retention during peritonitis

Functional analysis of the C-reactive protein (CRP) gene -717A>G polymorphism associated with coronary heart disease

<p>Abstract</p> <p>Background</p> <p>Atherosclerosis underlies the major pathophysiological mechanisms of coronary heart disease (CHD), and inflammation contributes to all phases of atherosclerosis. C-reactive protein (CRP), a sensitive, but nonspecific marker of inflammation has been shown to play proatherogenic roles in the process of atherosclerosis. Our previous report showed that rs2794521 (-717A>G), located in the promoter of the CRP gene, was independently associated with CHD in Chinese subjects. In the present study, we tried to investigate the biological significance of this genetic variation <it>in vitro</it>.</p> <p>Methods</p> <p>The influence of G to A substitution at the site of rs2794521 on the transcriptional activity of the promoter of the CRP gene was assessed by luciferase reporter assay, and protein binding to the site of rs2794521 was detected by EMSA assay.</p> <p>Results</p> <p>The G to A exchange at the site of rs2794521 resulted in an increased transcriptional activity of the promoter of CRP gene, and glucocorticoid receptor (GR) protein factor bound drastically differently to the A and G alleles at the site of rs2794521.</p> <p>Conclusion</p> <p>These results provided functional evidence supporting the association of the SNP rs2794521 of the CRP gene with CHD probably through regulating the expression level of CRP by different variations of rs2794521.</p

A Novel Docetaxel-Loaded Poly (ε-Caprolactone)/Pluronic F68 Nanoparticle Overcoming Multidrug Resistance for Breast Cancer Treatment

Multidrug resistance (MDR) in tumor cells is a significant obstacle to the success of chemotherapy in many cancers. The purpose of this research is to test the possibility of docetaxel-loaded poly (ε-caprolactone)/Pluronic F68 (PCL/Pluronic F68) nanoparticles to overcome MDR in docetaxel-resistance human breast cancer cell line. Docetaxel-loaded nanoparticles were prepared by modified solvent displacement method using commercial PCL and self-synthesized PCL/Pluronic F68, respectively. PCL/Pluronic F68 nanoparticles were found to be of spherical shape with a rough and porous surface. The nanoparticles had an average size of around 200 nm with a narrow size distribution. The in vitro drug release profile of both nanoparticle formulations showed a biphasic release pattern. There was an increased level of uptake of PCL/Pluronic F68 nanoparticles in docetaxel-resistance human breast cancer cell line, MCF-7 TAX30, when compared with PCL nanoparticles. The cytotoxicity of PCL nanoparticles was higher than commercial Taxotere®in the MCF-7 TAX30 cell culture, but the differences were not significant (p > 0.05). However, the PCL/Pluronic F68 nanoparticles achieved significantly higher level of cytotoxicity than both of PCL nanoparticles and Taxotere®(p < 0.05), indicating docetaxel-loaded PCL/Pluronic F68 nanoparticles could overcome multidrug resistance in human breast cancer cells and therefore have considerable potential for treatment of breast cancer

Advances in Catalytic C–F Bond Activation and Transformation of Aromatic Fluorides

The activation and transformation of C–F bonds in fluoro-aromatics is a highly desirable process in organic chemistry. It provides synthetic methods/protocols for the generation of organic compounds possessing single or multiple C–F bonds, and effective catalytic systems for further study of the activation mode of inert chemical bonds. Due to the high polarity of the C–F bond and it having the highest bond energy in organics, C–F activation often faces considerable academic challenges. In this mini-review, the important research achievements in the activation and transformation of aromatic C–F bond, catalyzed by transition metal and metal-free systems, are presented

The hypertension risk variant Rs820430 functions as an enhancer of SLC4A7

BACKGROUND The large-scale meta-analysis of genome-wide association study (GWAS) recently identified a genomic locus where the genetic variant at rs820430 was strongly associated with hypertension in Chinese Han population, with its T allele conferred increased risks. However, the biological and disease-relevant mechanisms for this association remain elusive. METHODS A group of 275 participants from rural district of Shandong Province were enrolled, rs820430 was genotyped using genomic DNA with the fluorogenic 5'-nuclease TaqMan allelic discrimination assay system (Applied Biosystems, CA). In vitro experiments were performed in this study, such as luciferase reporter assays, gel mobility shift assays (electrophoretic mobility shift assay), and chromatin immunoprecipitation. RESULTS We found the risk T allele of rs820430 was associated with higher SLC4A7 mRNA level in cohort population. Furthermore, we characterized a cis-regulatory mechanism that the T allele of rs820430 distinctively increased c-Fos transcription factor binding, by which leading to increased SLC4A7 expression. CONCLUSIONS The present study indicated that the disease-associated T allele of a new hypertension risk variant rs820430 linked increased hypertension risk through higher SLC4A7 expression, and rs820430 functioned as an enhancer of SLC4A7 transcription by allele distinctively increased c-Fos transcription factor binding

PNP-Ligated Rare-Earth Metal Catalysts for Efficient Polymerization of Isoprene

The tridentate PNP ligand-supported rare-earth metal complexes, i.e., bis[o-diphenylphosphinophenyl]amido-Re-bis[o-dimethylaminobenzyl], [(Ph2P-o-C6H4)2N]Re[(CH2-o-Me2N(C6H4))2]: (Re = Y, 1; Nd, 2; Gd, 3) were applied to isoprene polymerization. When activated with borate activator ([PhMe2NH][B(C6F5)4] (NH-BARF), catalysts 1 and 3 exhibited excellent catalytic efficiency in aromatic media, produced very-high to ultrahigh molecular weight (Mw over 130 × 104 g/moL) polyisoprene rubber (PIR), and the obtained PIR contained over 98% cis-1,4 head-to-tail repeating unites. In most cases, the borate-activated polymerization reaction proceeded in a quasi-living pattern (PDI = 1.2–1.5) under controlled monomer conversion; whereas, activated with the commercially available modified methylaluminoxane (MMAO3A) in aliphatic hydrocarbon media, complexes 1, 2 and 3 all showed high catalytic efficiency, produced high molecular weight PIR with narrow molecular weight distribution (PDI ≤ 2.0) and high cis-1,4 head-to tail repeating unites in the range of 91–95%. Thus, the catalyst systems that consisted of 1, 2 and 3/MMAO3A, are closely relevant to the current industrial polybutadiene rubber (PBR) and PIR production processes

Comparison of Multiple Radiomics Models for Identifying Histological Grade of Pancreatic Ductal Adenocarcinoma Preoperatively Based on Multiphasic Contrast-Enhanced Computed Tomography: A Two-Center Study in Southwest China

Background: We designed and validated the value of multiple radiomics models for diagnosing histological grade of pancreatic ductal adenocarcinoma (PDAC), holding a promise of assisting in precision medicine and providing clinical therapeutic strategies. Methods: 198 PDAC patients receiving surgical resection and pathological confirmation were enrolled and classified as 117 low-grade PDAC and 81 high-grade PDAC group. An external validation group was used to assess models’ performance. Available radiomics features were selected using GBDT algorithm on the basis of the arterial and venous phases, respectively. Five different machine learning models were built including k-nearest neighbour, logistic regression, naive bayes model, support vector machine, and random forest using ten times tenfold cross-validation. Multivariable logistic regression analysis was applied to establish clinical model and combined model. The models’ performance was assessed according to its predictive performance, calibration curves, and decision curves. A nomogram was established for visualization. Survival analysis was conducted for stratifying the overall survival prior to treatment. Results: In the training group, the RF model demonstrated the optimal predictive ability and robustness with an AUC of 0.943; the SVM model achieved the secondary performance, followed by Bayes model. In the external validation group, these three models (Bayes, RF, SVM) also achieved the top three predictive ability. A clinical model was built by selected clinical features with an AUC of 0.728, and combined model was established by an RF model and a clinical model with an AUC of 0.961. The log-rank test revealed that the low-grade group survived longer than the high-grade group. Conclusions: The multiphasic CECT radiomics models offered an accurate and noninvasive perspective to differentiate histological grade in PDAC and advantages of machine learning models including RF, SVM and Bayes were more remarkable