Molecular Characterization of Chemosensory Protein (CSP) Genes and the Involvement of AgifCSP5 in the Perception of Host Location in the Aphid Parasitoid Aphidius gifuensis.

Aphidius gifuensis is the dominant parasitic natural enemy of aphids. Elucidating the molecular mechanism of host recognition of A. gifuensis would improve its biological control effect. Chemosensory proteins (CSPs) play a crucial role in insect olfactory systems and are mainly involved in host localization. In this study, a total of nine CSPs of A. gifuensis with complete open reading frames were identified based on antennal transcriptome data. Phylogenetic analysis revealed that AgifCSPs were mainly clustered into three subgroups (AgifCSP1/2/7/8, AgifCSP3/9, and AgifCSP4/5/6). AgifCSP2/5 showed high expression in the antennae of both sexes. Moreover, AgifCSP5 was found to be specifically expressed in the antennae. In addition, fluorescent binding assays revealed that AifCSP5 had greater affinities for 7 of 32 volatile odor molecules from various sources. Molecular docking and site-directed mutagenesis results revealed that the residue at which AgifCSP5 binds to these seven plant volatiles is Tyr75. Behavior tests further confirmed that trans-2-nonenal, one of the seven active volatiles in the ligand binding test, significantly attracted female adults at a relatively low concentration of 10 mg/mL. In conclusion, AgifCSP5 may be involved in locating aphid-infested crops from long distances by detecting and binding trans-2-nonenal. These findings provide a theoretical foundation for further understanding the olfactory recognition mechanisms and indirect aphid localization behavior of A. gifuensis from long distances by first identifying the host plant of aphids.

Characterization and Mechanism Study of a Novel PL7 Family Exolytic Alginate Lyase from Marine Bacteria Vibrio sp. W13.

Alginate lyase can degrade alginate into oligosaccharides through ß-elimination for various biological, biorefinery, and agricultural purposes. Here, we report a novel PL7 family exolytic alginate lyase VwAlg7A from marine bacteria Vibrio sp. W13 and achieve the heterologous expression in E. coli BL21 (DE3). VwAlg7A is 348aa with a calculated molecular weight of 36 kDa, containing an alginate lyase 2 domain. VwAlg7A exhibits specificity towards poly-guluronate. The optimal temperature and pH of VwAlg7A are 30 °C and 7.0, respectively. The activity of VwAlg7A can be significantly inhibited by the Ni2+, Zn2+, and NaCl. The Km and Vmax of VwAlg7A are 36.9 mg/ml and 395.6 µM/min, respectively. The ESI and HPAEC-PAD results indicate that VwAlg7A cleaves the sugar bond in an exolytic mode. Based on the molecular docking and mutagenesis results, we further confirmed that R98, H169, and Y303 are important catalytic residues.

Hyperbranched polymer functionalized flexible perovskite solar cells with mechanical robustness and reduced lead leakage.

Perovskite solar cells (PSCs) are multilayer structures. The interface between electron transport layer and perovskite is the mechanical weakest point in flexible PSCs due to its low fracture energy. Herein, we develop a highly adhesive polyamide-amine-based hyperbranched polymers to reinforce the interface. The interface fracture energy is improved from 1.08 to 2.13 J·m-2 by the hyperbranched polymers with adhesive groups and dynamic hydrogen bond networks. The polymer functionalized perovskite solar cells achieve superior power conversion efficiencies of 25.05% and 23.86% for rigid and flexible devices, respectively. Furthermore, the hyperbranched polymer contains abundant intramolecular cavities that can capture Pb2+. Pb leakage after solar cell damage is effectively suppressed. Our findings provide insights on designing adhesive interface layers towards high-efficiency, mechanical-stable and environment-friendly flexible perovskite solar cells.

[Study of salivary metabonomics in patients with oral squamous cell carcinoma and leukoplakia].

PURPOSE: The objective of this study was to detect and analyze the existence of differential metabolites from saliva of patients with oral squamous cell carcinoma(OSCC) by metabonomics method, and to evaluate its application value on clinical diagnosis or screening of OSCC. METHODS: The collected saliva samples for OSCC patients, oral leukoplakiac(OLK) patients who were pathologically diagnosed and met the inclusion criteria were analyzed using metabonomics methods (GC-TOF-MS). The results were analyzed by principal component analysis and orthogonal partial least squares discriminant analysis using SIMCA software. RESULTS: The metabolic profiles of OSCC, OLK and healthy control group showed significant differences (P<0.05). In total, 15 typical differential metabolites among the three groups were detected. Further study focusing on metabolic pathway revealed imbalance of protein, energy and lipid metabolism between OSCC and OLK patients. Abnormal tricarboxylic acid cycle was detected as well. CONCLUSIONS: Metabonomics methods is feasible for differential metabolites analysis,15 differential metabolites were detected in OSCC,OLK patients and healthy people. These findings will contribute to the early screening of oral squamous cell carcinoma.

Arabidopsis CIB3 regulates photoperiodic flowering in an FKF1-dependent way.

Arabidopsis cryptochrome 2 (CRY2) and FLAVIN-BINDING, KELCH REPEAT, and F-BOX 1 (FKF1) are blue light receptors mediating light regulation of growth and development, such as photoperiodic flowering. CRY2 interacts with a basic helix-loop-helix transcription factor CIB1 in response to blue light to activate the transcription of the flowering integrator gene FLOWERING LOCUS T (FT). CIB1, CIB2, CIB4, and CIB5 function redundantly to promote flowering in a CRY2-dependent way and form various heterodimers to bind to the noncanonical E-box sequence in the FT promoter. However, the function of CIB3 has not been described. We discovered that CIB3 promotes photoperiodic flowering independently of CRY2. Moreover, CIB3 does not interact with CRY2 but interacts with CIB1 and functions synergistically with CIB1 to promote the transcription of the GI gene. FKF1 is required for CIB3 to promote flowering and enhances the CIB1-CIB3 interaction in response to blue light.

Perioperative risk factors predict one-year mortality in patients with acute type-A aortic dissection.

OBJECTIVE: The goal of this study was to analyze perioperative risk factors to predict one- year mortality after operation for acute type A aortic dissection (AAD). METHODS: A total of 121 consecutive patients undergoing Stanford type A AAD surgery in Beijing Anzhen Hospital were enrolled. Preoperative clinical and laboratory data from patients were collected. RESULTS: Multivariable Cox regression analysis showed that significant factors associated with increased one-year mortality were elder age (year) (hazard ratio (HR) 1.0985; 95% confidence interval (CI) 1.0334-1.1677), intraoperative blood transfusion ≥2000 mL (HR 8.8081; 95% CI 2.3319-33.2709), a higher level of serum creatinine (µmol/L) at postoperative one day (HR 1.0122; 95% CI 1.0035-1.0190) and oxygenation index (OI) < 200 (mmHg) at the end of surgery (HR 5.7575; 95% CI 1.1695-28.3458). CONCLUSION: In this study, perioperative risk factors to predict one-year prognosis are age, intraoperative blood transfusion ≥2000 mL, postoperative OI < 200 mmHg and level of postoperative serum creatinine. The results aid in the comprehension of surgical outcomes and assist in the optimization of treatment strategies for those with perioperative risk factors to decrease one-year mortality.

Enhanced coupling through π-stacking in imidazole-based molecular junctions.

We demonstrate that imidazole based π-π stacked dimers form strong and efficient conductance pathways in single-molecule junctions using the scanning-tunneling microscope-break junction (STM-BJ) technique and density functional theory-based calculations. We first characterize an imidazole-gold contact by measuring the conductance of imidazolyl-terminated alkanes (im-N-im, N = 3-6). We show that the conductance of these alkanes decays exponentially with increasing length, indicating that the mechanism for electron transport is through tunneling or super-exchange. We also reveal that π-π stacked dimers can be formed between imidazoles and have better coupling than through-bond tunneling. These experimental results are rationalized by calculations of molecular junction transmission using non-equilibrium Green's function formalism. This study verifies the capability of imidazole as a Au-binding ligand to form stable single- and π-stacked molecule junctions at room temperature.

[Distribution Characteristics and Health Risk Assessment of Thirteen Sulfonamides Antibiotics in a Drinking Water Source in East China].

Trace levels of residual antibiotics in drinking water sources may threaten public health and becomes a serious issue in modern society. Occurrence and distribution of 13 sulfonamides antibiotics in a drinking water source in East China were investigated using solid phase extraction-high performance liquid chromatography-tandem mass spectrometry. The results revealed that all 13 sulfonamides were detected with the total concentrations ranging from 10.5 ng·L-1 to 238.5 ng·L-1. Sulfamethoxazole (SMX) and sulfonamide (SAM) presented the 100% detected frequency, and the maximum concentrations reached 107.0 ng·L-1 and 43.1 ng·L-1, respectively. Sulfonamides contamination levels in the inlet were relatively higher than those in the outlet. The concentration of SMX was substantially unchanged in different positions of drinking water source. Seasonal variation of sulfonamide concentration showed that the concentrations were higher in winter and spring compared with those in summer and autumn. The range of total sulfonamides concentration detected in winter and spring was from 110.8 ng·L-1 to 117.9 ng·L-1, which was 3.6-3.8 times higher than those in summer and autumn. Human health risk characterization of residual sulfonamides in drinking water source was based on the assessment of risk quotients (RQs) for which different life stages were taken into account. The results showed that no sulfonamides had a RQs higher than 1. Trimethoprim (TMP) was the most risky antibiotic to the 0-3 months old infants with RQs reaching 0.001. Although the sulfonamides detected in the drinking water source do not pose any risk to the peoples' health, the implication of long-time exposure and comprehensive risk still deserve attention.

Effects of ellagic acid-rich extract of pomegranates peel on regulation of cholesterol metabolism and its molecular mechanism in hamsters.

The study investigated the effect of pomegranates ellagic acid (PEA) on blood cholesterol and investigated its effects on LXR/RXR/PPAR-ABCA1 nuclear receptors-signaling pathways of cholesterol metabolism on molecular level in hamsters. In this experiment, hamsters were randomly divided into two groups: the first group (NG, n = 9) was always fed the normal diet, whereas the other group (HFG, n = 45) was fed a high fat diet during the first 4 weeks and then fed the normal diet for the last 4 weeks. In HFG, which was divided into five groups (n = 9) during the last 4 weeks, three groups were treated with PEA at 44 mg per kg bw, 88 mg per kg bw and 177 mg per kg bw, one group was treated with simvastatin at 1.77 mg per kg bw, and one was given sterile double-distilled water. The data validated that PEA dose-dependently decreased plasma total cholesterol and triglyceride level accompanied by a greater excretion of fecal bile acid. The result of RT-PCR revealed that PEA up-regulated liver X receptor (LXRα), peroxisome proliferator-activated receptor α (PPARα), peroxisome proliferator-activated receptor γ (PPARγ) and their downstream gene ATP-binding cassette transporter A1 (ABCA1), with no effect on retinoid X receptor (RXRα). PEA promoted cholesterol removal by enhancing fecal bile acid and up-regulation of the two pathways, LXR/PPAR-ABCA1. Moreover, PEA was stronger than simvastatin in some aspects.