Morphology and phylogeny of Cytospora (Cytosporaceae, Diaporthales) species associated with plant cankers in Tibet, China.

During our biodiversity investigations in Tibet, China, typical Cytospora canker symptoms were observed on branches of hosts Myricariapaniculate, Prunuscerasifera and Sibiraeaangustata. Samples were studied, based on morphological features coupled with multigene phylogenetic analyses of ITS, act, rpb2, tef1 and tub2 sequence data, which revealed two new species (Cytosporamyricicolasp. nov. and C.sibiraeicolasp. nov.) and a known species (C.populina). In addition, Cytosporapopulina is newly discovered on the host Prunuscerasifera and in Tibet.

Postsynthetic Modification of Thermo-Treated Metal-Organic Framework for Combined Photothermal/Photodynamic Antibacterial Therapy.

Metal-organic frameworks (MOFs) are emerging porous materials that can serve as carriers of photosensitizers and photothermal agents. Meanwhile, a large number of active sites in MOFs endow them with the characteristics of modification by postsynthetic modification. Herein, a dual-modal PDT/PTT therapeutic agent HMIL-121-acriflavine-tetrakis (4-amoniophenyl) porphyrin (HMIL-ACF-Por), prepared by the postsynthetic modification of the MOF (HMIL-121), was reported for antibacterial applications. The prepared HMIL-ACF-Por enables the generation of abundant reactive oxygen species, including the superoxide anion radical (O2-) and singlet oxygen (1O2), and thermal energy under 808 nm NIR laser irradiation. HMIL-ACF-Por showed good antibacterial ability against Escherichia coli and Staphylococcus aureus in vitro. Meanwhile, HMIL-ACF-Por can effectively inhibit the inflammatory response caused by bacterial infection and accelerate S. aureus-infected wound healing under laser irradiation owing to the synergistic effect of photodynamic therapy (PDT) and photothermal therapy (PTT). These results demonstrate that HMIL-ACF-Por is a promising PDT/PTT therapeutic agent. This work also contributes to offering an effective solution for treating bacterial infections and promotes the application of MOF-based materials in biomedicine.

Simulating the effect of climate change on soil microbial community in an Abies georgei var. smithii forest.

Qinghai-Tibet Plateau is considered a region vulnerable to the effects of climate change. Studying the effects of climate change on the structure and function of soil microbial communities will provide insight into the carbon cycle under climate change. However, to date, changes in the successional dynamics and stability of microbial communities under the combined effects of climate change (warming or cooling) remain unknown, which limits our ability to predict the consequences of future climate change. In this study, in situ soil columns of an Abies georgei var. smithii forest at 4,300 and 3,500 m elevation in the Sygera Mountains were incubated in pairs for 1 year using the PVC tube method to simulate climate warming and cooling, corresponding to a temperature change of ±4.7°C. Illumina HiSeq sequencing was applied to study alterations in soil bacterial and fungal communities of different soil layers. Results showed that warming did not significantly affect the fungal and bacterial diversity of the 0-10 cm soil layer, but the fungal and bacterial diversity of the 20-30 cm soil layer increased significantly after warming. Warming changed the structure of fungal and bacterial communities in all soil layers (0-10 cm, 10-20 cm, and 20-30 cm), and the effect increased with the increase of soil layers. Cooling had almost no significant effect on fungal and bacterial diversity in all soil layers. Cooling changed the structure of fungal communities in all soil layers, but it showed no significant effect on the structure of bacterial communities in all soil layers because fungi are more adapted than bacteria to environments with high soil water content (SWC) and low temperatures. Redundancy analysis (RDA) and hierarchical analysis showed that changes in soil bacterial community structure were primarily related to soil physical and chemical properties, whereas changes in soil fungal community structure primarily affected SWC and soil temperature (Soil Temp). The specialization ratio of fungi and bacteria increased with soil depth, and fungi were significantly higher than bacteria, indicating that climate change has a greater impact on microorganisms in deeper soil layers, and fungi are more sensitive to climate change. Furthermore, a warmer climate could create more ecological niches for microbial species to coexist and increase the strength of microbial interactions, whereas a cooler climate could have the opposite effect. However, we found differences in the intensity of microbial interactions in response to climate change in different soil layers. This study provides new insights to understand and predict future effects of climate change on soil microbes in alpine forest ecosystems.

Estimation of morphological variation in seed traits of Sophora moorcroftiana using digital image analysis.

Sophora moorcroftiana is a leguminous plant endemic to the Qinghai-Tibet Plateau. It has excellent abiotic stress tolerance and is considered an ideal species for local ecological restoration. However, the lack of genetic diversity in the seed traits of S. moorcroftiana hinders its conservation and utilization on the plateau. Therefore, in this study, genotypic variation and phenotypic correlations were estimated for nine seed traits among 15 accessions of S. moorcroftiana over two years, 2014 and 2019, respectively from 15 sample points. All traits evaluated showed significant (P< 0.05) genotypic variation. In 2014, accession mean repeatability was high for seed perimeter, length, width, and thickness, and 100-seed weight. In 2019, mean repeatability for seed perimeter and thickness, and 100-seed weight were high. The estimates of mean repeatability for seed traits across the two years ranged from 0.382 for seed length to 0.781 for seed thickness. Pattern analysis showed that 100-seed weight was significantly positively correlated with traits such as seed perimeter, length, width, and thickness, and identified populations with breeding pool potential. In the biplot, principal components 1 and 2 explained 55.22% and 26.72% of the total variation in seed traits, respectively. These accessions could produce breeding populations for recurrent selection to develop S. moorcroftiana varieties suitable for restoring the fragile ecological environment of the Qinghai-Tibet Plateau.

Molecular epidemiology of hepatitis B virus genotypes and subgenotypes in ethnic minority populations, Yunnan province, China.

The aim of our study was to determine the distribution of hepatitis B virus (HBV) genotypes and subgenotypes in ethnic minorities in Yunnan province to provide evidence supporting the theoretical basis for hepatitis B prevention and control. We obtained serum samples and demographic data from 765 individuals reported by Yunnan province who had either acute or chronic HBV infection and were from one of 20 ethnic minority populations: Achang, Bai, Brown, Tibetan, Dai, Deang, Dulong, Hani, Hui, Jingpo, Lahu, Yi, Lisu Miao, Naxi, Nu, Pumi, Wa, Yao, or Zhuang people. We sequenced the HBV DNA and determined the genotypes and subgenotypes of the isolated HBVs. We mapped the genotype and subgenotype distribution by ethnic minority population and conducted descriptive analyses. There were four genotypes among the 20 ethnic groups: genotype B (21.3% of samples), C (76.6%), D (1.8%) and I (0.3%). The most common subgenotype was C1. There were no genotype differences by gender (P = 0.954) or age (P = 0.274), but there were differences by region (P < 0.001). There were differences in genotype distribution (P < 0.001) and subgenotype distribution (P = 0.011) by ethnic group. Genotype D was most prominent in Tibet and most HBV isolates were C/D recombinant viruses. The only two genotype I virus isolates were in Zhuang people. Susceptibility and geographic patterns may influence HBV prevalence in different ethnic populations, but additional research is needed for such a determination.

Measles vaccination among children in border areas of Yunnan Province, Southwest China.

BACKGROUND: Border areas are at high risk of measles epidemics. This study aimed to evaluate the effectiveness of the implementation of the routine two-dose measles containing vaccine (MCV) program in border counties of Southwest China. METHODS: Data used in the study were derived from a cross-sectional survey among 1,467 children aged 8 to 84 months from five border counties of Yunnan Province, Southwest China in 2016. The participants were recruited using a multistage sampling method. Primary guardians of the children were interviewed to collect information on vaccination history, socio-economic status, and knowledge about immunization. Both coverage and timely coverage for the first (MCV1) and the second (MCV2) dose of MCV were calculated. The Kaplan-Meier method was performed to estimate the cumulative coverage of MCV, and Log-rank tests were adopted to compare the differences across counties and birth cohorts. Univariate and multivariate logistic regression models were used to investigate the predictors of delayed MCV1 vaccination. RESULTS: The coverage for MCV1 and MCV2 were 97.5% and 93.4%, respectively. However, only 63.8% and 84.0% of the children received MCV1 or MCV2 on time. Significant differences in the cumulative coverage were detected across counties and birth cohorts. Results of the multivariate logistic regression analysis indicated that children whose primary guardian knew the schedule of MCV were less likely to receive MCV1 late (OR = 0.63, P<0.01). For the guardians, doctors at vaccination units were the primary and also the most desired source of vaccination information. CONCLUSIONS: Although the coverage for MCV is high in border areas of Southwest China, the timeliness of MCV vaccination seems suboptimal. Tailored information from local health professionals may help to reduce untimely vaccination.

Tirofiban Promotes the Proliferation of Human Umbilical Vein Endothelial Cells In Vitro Via Enhanced Vascular Endothelial Growth Factor Expression.

BACKGROUND: In the design and development of small-caliber artificial blood vessels, endothelialization is a key issue, but it is not well understood at present. Some studies have used vascular endothelial growth factor (VEGF) sustained-release methods to promote endothelial cell proliferation. However, this method is not ideal. This study has used drugs to induce endothelial cells to produce VEGF. This method in turn functions to promote cell proliferation and promote the endothelialization of artificial blood vessels. This study aimed to investigate the effect of the antiplatelet drug tirofiban on endothelial cell proliferation in vitro. METHODS: In this study, human umbilical vein endothelial cells (HUVECs) were used to determine the effect of tirofiban-stimulated cell proliferation. Analysis of cell proliferation, assayed by the Cell Counting Kit-8 assay, showed that the number of cells was increasingly higher than in the absence of tirofiban. It was also observed that heparin enhanced the tirofiban effect. The cell VEGF expression at different time points after tirofiban addition was detected by western blot analysis. RESULTS: The absorbance values of the experimental (1 µg/mL tirofiban) and the control groups (0 tirofiban) were 1.74 (SD, 0.03) and 1.51 (SD, 0.07) (P < .001), respectively, after 4 days of culture under the same conditions. The amount of VEGF produced by HUVECs gradually increased after treatment with tirofiban, reached a peak at 2 hours, and was 1.3-fold greater than the control group (P = .034). Compared with the tirofiban-only group, the absorbance value of the tirofiban and 10 µg/mL of heparin group was significantly increased (P < .001). CONCLUSIONS: Tirofiban promoted the proliferation of HUVECs by promoting the synthesis of VEGF in HUVECs. Heparin enhanced tirofiban activity in promoting HUVEC proliferation.

The complete chloroplast genome of Abies georgei Orr var. smithii, a species endemic to the Qinghai-Tibet Plateau, China.

Abies georgei Orr var. smithii is an evergreen coniferous species of Pinaceae, and is endemic to the Qinghai-Tibet Plateau of China. Considering its vital ecological functions in this unique area, the complete chloroplast (cp) genome was constructed in this study to provide genetic information for its further study of conservation and evolution. The complete cp genome is 121,213 bp in length with GC content of 38.3%, and contains a tetrad structure, including a large single copy region of 76,278 bp, a small single copy of 42,575 bp, and two very short repeats of 1,180 bp for each. Besides, it contains 113 genes in total, including 74 CDSs, 35 tRNAs, and four rRNAs. This genome has been deposited in Genbank under accession number of MT527722.

The complete chloroplast genome sequence of Juniperus saltuaria (Cupressaceae).

In order to supply genetic information of Juniperus saltuaria, we reported the complete chloroplast genome sequence based on high-throughput sequencing data. The whole chloroplast genome was 128,099 bp long with an asymmetric base composition (32.9% A, 16.9% C, 18.1% G and 32.1% T). The genome annotation predicted a total of 116 genes, including 82 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. The neighbor-joining phylogenetic analysis based on 45 complete chloroplast genome sequences showed that J. saltuaria was more closely related to the congeneric J. recurva. The assembled chloroplast genome of J. saltuaria will provide useful genomic data both for the phylogenetic research of Juniperus and the conservation of this species.

Completed plastome sequence of Sophora moorcroftiana, an endemic shrub to the Qinghai-Tibet Plateau, China.

Sophora moorcroftiana, an endemic Fabaceae species occurred in the Qinghai-Tibet plateau, China, has important economic value in local. Its completed plastome sequence is 148,930 bp in size, and comprises a pair of inverted repeat (IR) regions of 23,787 bp each, a large single-copy region of 83,342 bp and a small single-copy region of 18,014 bp. The GC content of the plastome was 30.2%. A total of 124 genes were identified, comprising 80 protein-coding genes, 36 tRNA genes and eight rRNA genes. There are 94 unique genes, with 15 genes duplicated in the IR regions. Phylogenetic tree shows that plastome of S. moorcroftiana is most related to that of S. alopecuroides. This plastome would be helpful for the study of molecular mechanism of photosynthesis, sustainable conservation, genetic improvement of S. moorcroftiana.

Delay-dependent fuzzy static output feedback control for discrete-time fuzzy stochastic systems with distributed time-varying delays.

This paper is concerned with the delay-dependent H(∞) fuzzy static output feedback control scheme for discrete-time Takagi-Sugeno (T-S) fuzzy stochastic systems with distributed time-varying delays. To begin with, the T-S fuzzy stochastic system is transformed to an equivalent switching fuzzy stochastic system. Then, based on novel matrix decoupling technique, improved free-weighting matrix technique and piecewise Lyapunov-Krasovskii function (PLKF), a new delay-dependent H(∞) fuzzy static output feedback controller design approach is first derived for the switching fuzzy stochastic system. Some drawbacks existing in the previous papers such as matrix equalities constraint, coordinate transformation, the same output matrices, diagonal structure constraint on Lyapunov matrices and BMI problem have been eliminated. Since only a set of LMIs is involved, the controller parameters can be solved directly by the Matlab LMI toolbox. Finally, two examples are provided to illustrate the validity of the proposed method.

[Comparative study on acute toxicity and pharmacological effect of huoxiang zhengqi microemulsion and huoxiang zhengqi tincture].

OBJECTIVE: To compare the acute toxicity and the pharmacological effect of Huoxiang Zhengqi microemulsion and Huoxiang Zhengqi tincture. METHOD: The acute toxicities of Huoxiang Zhengqi microemulsion and Huoxiang Zhengqi tincture were observed by the test of maximum dose in mice and the antidiarrheal effects of them were evaluated by ED50 values of the diarrhea index, the serum levels of gastrin and motilin in the mice diarrhea model induced by senna. RESULT: The acute toxicity of Huoxiang Zhengqi tincture was much higher than that of Huoxiang Zhengqi microemulsion and the ED50 values of the two formulations were similar. CONCLUSION: The microemulsion of Huoxiang Zhengqi prescription was much safer than that of tincture, but the antidiarrheal effects of them in diarrhea model induced by senna were similar.

Litchi flavonoids: isolation, identification and biological activity.

The current status of the isolation, identification, biological activity, utilization and development prospects of flavonoids found in litchi fruit pericarp (LFP) tissues is reviewed. LFP tissues account for approximately 15% by weight of the whole fresh fruit and are comprised of significant amount of flavonoids. The major flavonoids in ripe LFP include flavonols and anthocyanins. The major flavanols in the LFP are reported to be procyanidin B4, procyanidin B2 and epicatechin, while cyanindin-3-rutinside, cyanidin-3-glucoside, quercetin-3-rutinosde and quercetin-3-glucoside are identified as the important anthocyanins. Litchi flavanols and anthocyanins exhibit good potential antioxidant activity. The hydroxyl radical and superoxide anion scavenging activities of procyanidin B2 are greater than those of procyanidin B4 and epicatechin, while epicatechin has the highest alpha,alpha-diphenyl-beta-picrylhydrazyl radical (DPPH*) scavenging activity. In addition to the antioxidant activity, LFP extract displays a dose- and time-dependent inhibitory effect on human breast cancer, which could be attributed, in part, to its inhibition of proliferation and induction of apoptosis in cancer cells through upregulation and down-regulation of multiple genes. Furthermore, various anticancer activities are observed for epicatechin, procyanidin B2, procyanidin B4 and the ethyl acetate fraction of LFP tissue extracts. Procyanidin B4 and the ethyl acetate fraction show a stronger inhibitory effect on HELF than MCF-7 proliferation, while epicatechin and procyanidin B2 have lower cytotoxicities towards MCF-7 and HELF than paclitaxel. It is therefore suggested that flavonoids from LFP might be potentially useful components for functional foods and/or anti-breast cancer drugs.