Dynamic Changes of Soil Microbial Communities During the Afforestation of Pinus Armandii in a Karst Region of Southwest China.

Clarifying the response of soil microbial communities to vegetation restoration is essential to comprehend biogeochemical processes and ensure the long-term viability of forest development. To assess the variations in soil microbial communities throughout the growth of Pinus armandii plantations in the karst region, we utilized the "space instead of time" approach and selected four P. armandii stands with ages ranging from 10 to 47 years, along with a grassland control. The microbial community structure was determined by conducting Illumina sequencing of the 16 S rRNA gene and the ITS gene, respectively. The results demonstrated that afforestation with P. armandii significantly influenced soil microbial communities, as indicated by notable differences in bacterial and fungal composition and diversity between the plantations and the control. However, soil microbe diversity did not display significant variation across stand ages. Moreover, the bacterial community exhibited higher responsiveness to age gradients compared to the fungal community. Soil physicochemical factors play a critical role in elucidating microbial diversity and community composition variations during restoration processes. TN, AN, TP, AP, SOC, AK, and pH were the most significant influencing factors for the composition of bacterial community, while TC, SOC, pH, and TCa were the most significant influencing factors for the composition of fungal community. Our findings indicate substantial changes in soil bacterial and fungal communities across successive stages of development. Additionally, the changes in dominant bacteria and fungi characteristics across the age gradient were primarily attributed to variations in the prevailing soil conditions and chemical factors.

The complete chloroplast genome of Pseudotsuga sinensis, a China endemic species.

In this study, we collected plant material from Pseudotsuga sinensis in Guizhou, China, and sequenced it. The complete chloroplast genome consisted of 122,243 bp, including a large single-copy (LSC) region, a small single-copy (SSC) region, and two inverted repeat regions like those in P. sinensis var. wilsoniana. The GC content of P. sinensis and P. sinensis var. wilsoniana are 38.7% and 38.8%, respectively. The reconstructed phylogenetic tree reveals that P. sinensis was a sister species to P. sinensis var. wilsoniana. Hence, the availability of the chloroplast genome of P. sinensis will promote further phylogenetic studies of the family Pinaceae.

Surface modification of cerasomes with AuNPs@poly(ionic liquid)s for an enhanced stereo biomimetic membrane electrochemical platform.

A novel liposomal nanocomposite, Au@PIL-cerasome, with biocompatibility and conductivity was fabricated via the self-assembly of cerasomes and gold nanoparticles (AuNPs) stabilized by poly(ionic liquid)s (PILs). The surface charge, morphology and chemical composition of the nanocomposites were characterized by the zeta potential, UV-vis, TEM, SEM and EDS. The nanocomposites exhibited structural stability directly on the surface of solid electrodes, without fusion. Electrochemical impedance experiments demonstrated that the nanocomposites had an enhanced conductivity compared with unmodified cerasomes. Horseradish peroxidase (HRP), as a reporter, was immobilized on the nanocomposites without denaturation or inactivation. The direct electron transfer of HRP was achieved, and the HRP/Au@PIL-cerasome/GCE exhibited an amplified current and improved electrocatalytic activity. Activity towards H2O2 displayed a linear range over 10-70 µM and a detection limit of 3.3 µM. Activity towards NO2- displayed linear ranges over 1-5 mM and 5-1280 mM, and the limit of detection was 0.11 mM. In addition, the electrode was stable and reproducible, with 6% RSD. Such multi-component liposomal nanocomposites with an enhanced electrical performance pave a better way for building novel and straightforward 3D stereo biomimetic electrochemical platforms and even molecular communication systems to investigate information transduction between cells.

Efficacy and Safety of Gefitinib in Patients with Advanced Head and Neck Squamous Cell Carcinoma: A Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Trials on assessing the benefits of EGFR inhibitors in head and neck squamous cell carcinoma (HNSCC) patients have gradually been published. Nevertheless, the benefits of gefitinib in advanced HNSCC are still unknown. METHODS: The Cochrane library, PubMed, and EMBASE databases were systematically searched from the inception dates to 17 July 2017, 18 July 2017, and 19 July 2017, respectively. The keywords "head and neck" and gefitinib were used to retrieve in articles and abstracts. An additional search for recently published randomized trials was performed from July 17, 2017, to April 18, 2018. Then we assessed the risk of bias of the included studies based on the Cochrane "Risk of Bias" tool. Quantitative analysis was carried out to evaluate the overall survival (OS), progression free survival (PFS), overall response rate (ORR), and grade 3-4 adverse effects by Review Manager 5.0.2 and the quality-of-life was analyzed in the included studies. RESULTS: Seven randomized controlled trials and a total number of 1287 patients were involved. There were no significant differences in OS, PFS, or ORR between gefitinib and no gefitinib group (HR 1.07, 95% CI 0.93 to 1.22, and P=0.35; HR 0.84, 95% CI 0.69 to 1.04, and P=0.11; RR 1.04, 95% CI 0.90 to 1.20, and P =0.60, respectively). However, gefitinib alone was equivalent to chemotherapeutics (i.e., methotrexate; methotrexate + fluorouracil) in ORR in patients with recurrent HNSCC, and a trend of improvement in QOL in gefitinib group was showed. Toxicities revealed no differences except for diarrhea and skin toxicity (p=0.0003; p=0.03, respectively). CONCLUSION: For patients with advanced HNSCC, gefitinib cannot prolong the OS and PFS or improve ORR, and odds of skin toxicity and diarrhea increased. However, gefitinib alone is equivalent to methotrexate or methotrexate + fluorouracil and tends to improve QOL for recurrent patients.

Protective effects of notoginsenoside R1 on cerebral ischemia-reperfusion injury in rats.

The objective of this study was to investigate the protective effect of notoginsenoside R1 (NGR1) on cerebral ischemia-reperfusion injury (CIRI) in rats, and its molecular mechanism, to provide new insights into the diagnosis and treatment of CIRI. Sixty Sprague-Dawley rats were randomly divided into four groups including the sham-operation group (Sham), cerebral ischemia-reperfusion model group (CIR), NGR1 treatment group (NGR1), and nimodipine positive control group (NDC) with 15 rats each. Bilateral common carotid arteries occlusion was used to establish the rat CIRI model. The area of cerebral infarction at the end of reperfusion was calculated by triphenyl tetrazolium chloride staining. Apoptosis of hippocampal neurons in each group was detected by Annexin V/propidium iodide double staining. Hippocampal expression of brain-derived neurotrophic factor (BDNF) mRNA, and Bcl-2 and Bax protein at the end of reperfusion were measured by RT-qPCR and western blot analysis, respectively. Data were analyzed by SPSS software analysis to ensure statistical significance. At the end of reperfusion, the area of cerebral infarction in the NGR1 and NDC groups was significantly smaller than that of the CIR group. Apoptosis analysis showed that compared with the CIR group, the apoptosis rate of hippocampal neurons was significantly decreased in the NGR1 and NDC groups. RT-qPCR and western blot analysis showed that at the end of reperfusion, higher levels of BDNF mRNA and the anti-apoptotic factor, Bcl-2, and lower levels of the pro-apoptotic factor, Bax, in the hippocampus were found in the NGR1 and NDC groups compared with the CIR group. The protective effect of NGR1 on CIRI was significantly stronger than that of nimodipine. In conclusion, NGR1 can reduce the area of cerebral infarction, reduce apoptosis of hippocampal neurons, and protect rats from CIRI. Those effects were achieved by activating the expression of BDNF and Bcl-2, and by inhibiting the expression of Bax.

[New Bipyridinium Salt: Synthesis and Application as a Fluorescence Enhancement Probe of Nitrate Ion].

Anions are ubiquitously distributed not only in biological systems but also in environment. Accordingly, anion recognition and sensing have attracted increasing attention due to the important roles anion plays in biological, chemical and environmental fields. Among various anionic species, NO3- is a very important inorganic anions which has a great harm to the environment and human health. At present, methods for the determination of NO3- mainly contained electrochemical method, ion chromatography and ion selective electrode method. Although all methods have their own advantages, but also has the obvious deficiency. Such as, the reproducibility of electrochemical method is not good, and ion chromatography and ion selective electrode method usually require expensive apparatus and lengthy analytical time. As a contrast, fluorescence spectroscopy become a hot research topic in anion recognition and detection because of its high sensitivity and easy operation and other advantages in recent years. New bipyridinium salt L was designed and synthesized using pyrylium as a starting material. The molecular structure was determined by 1H NMR, 13C NMR, and high resolution mass spectrometry. The molecular recognition properties of L have been investigated through fluorescence titration experiments. The results indicate that L has sensitive and selective fluorescent response to NO3- among other different anions. Significant enhancements in the fluorescence intensity of L were observed when various concentrations of NO3- were added, while other competing anions have a quenching effect towards the initial fluorescence of solution. The fluorescence titration spectra shows that the bonding stoichiometry between receptor L and NO3- is 1 : 1 as a supramolecular complexes (1gK = 5 ± 0.02). The chemosensing properties of L were evaluated through quantum chemical calculations and the variable temperature 1H NMR titration. These results suggested that L has strong binding affinity towards NO3- with high selectivity, which may be ascribed to the specific hydrogen bonding between the L and active H atom of the bipyrydinium salts. The interaction between L and NO3- made the complex more planar compared with L giving rise to enhanced fluorescence and specific selectivity towards NO3-.