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1.
Artigo em Inglês | MEDLINE | ID: mdl-31903756

RESUMO

Stimuli-responsive microcapsules, which can release the encapsulated payload under various environmental stimuli, have attracted great interests from food, pharmaceutical, cosmetics and agricultural fields in recent years. However, most reported responsive microcapsules normally have single storage area and thus load/release only one type of payload under one stimulus. In this work, we fabricated a novel kind of multi-compartmental intelligent microcapsule with two storage areas and independently controlled (preprogrammable) releasing behavior under different stimuli via rapid photopolymerization of Pickering emulsions. In our strategy,a temperature-sensitive polymeric (pNIPAM) particles were prepared and loaded with Nile red (NR), which was then employed as Pickering emulsifier to stabilize oil-in-water droplets. The oil was composed of pH-responsive monomers and oil soluble fluorescent green (OG). Upon exposion to photo irradiation, pH-responsive monomers polymerized along the interior of the droplets and converted into microcapsules. With NR in the temperature-sensitive pNIPAM@NR particles and OG in the interior of the microcapsules, the as-prepared microcapsules possess dual-carrier capability with two payloads encapsulated dependently in the two different compartments. In addition, the microcapsules could respond to two different external stimuli (tempertature and pH) and realize the selective and independent release of encapsulated molecules (NR and OG) from the shell and core without any mutual interference. More importantly, the release of NR and OG can be programmed by preprogramming the order of the stimulus responses, the order of which can be altered. Our work develops a simple and effective strategy to fabricate responsive multi-compartment microcapsules with preprogrammable release of different molecules.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31916739

RESUMO

Recently, deep ultraviolet (DUV) detectors based on gallium oxide(Ga2O3)have a promising application in the industrial and aerospace due to their inherently ultra-wide bandgap (4.5-4.9 eV). Most of them are complicated in the process of being prepared, the lattice mismatch with the substrate and the expensive cost have to be taken into consideration. Faced with such problems, the solution-processible nanodots (NDs) with ultra-small size provide a solution. Here, we propose to use γ-Ga2O3 NDs as the DUV sensitive layer to construct a DUV p-i-n type detector with photovoltaic properties (p-Graphene/γ-Ga2O3 NDs/n-SiC). The device exhibits a high photoresponsivity (5.8 mA/W) and detectivity (7.6×1010 Jones) with a 250 nm source illumination under 0 V bias. Moreover, the DUV/UV injection ratio (R250/R360) reaches 103. These results demonstrates a new way to manufact low-cost, high-performance DUV detectors based on γ-Ga2O3.

3.
Medicine (Baltimore) ; 99(1): e18547, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31895793

RESUMO

BACKGROUND: Primary dysmenorrhea (PD) is one of the most common gynecological complaint among menstruating females. Acupuncture has been employed to relieve the pain-based symptoms and to avoid the side effects of conventional medication, especially, moxibustion has confirmed as an effective, convenient, and safe treatment for various types of menstrual pain. The purpose of this study is to systematically assess the effect and safety of moxibustion for treating PD. METHODS AND ANALYSIS: The following databases will be searched from their inception to December 2019: PubMed, Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, Wan-Fang Databases, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, Citation Information by National Institute of Informatics, Chinese Scientific Journal Database. Two reviewers will search these databases, select data and evaluate the quality of studies separately. The methodological quality will be measured by the Cochrane risk of bias tool. The primary outcome is the pain degree evaluation including visual analog scale, numerical visual scale, verbal rating scale, Cox retrospective symptom scale, or any other scale used to evaluate the level of pain. And the response rate involved overall reduction in symptoms. The adverse effects, quality of life will be assessed as secondary outcomes. Risk ratio for dichotomous data and mean differences with a 95% confidence interval for continuous data will be adopted to express the effect and safety of moxibustion for PD. TRIAL REGISTRATION NUMBER: PROSPERO CRD42019130141.

4.
Sci Total Environ ; 699: 134398, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31670038

RESUMO

A polyvinylidene fluoride plate sheet membrane coated 3D TiO2/poly (sodium styrenesulfonate) (PSS) photocatalyst layers were fabricated via dip-coating layer-by-layer (LbL) assembly. Cationic TiO2 and anionic PSS were alternately stacked on the support membrane via electrostatic interactions. The obtained modified membrane with (TiO2/PSS)7 exhibited optimal versatility under ultraviolet light irradiation in both dead-end and membrane reactor, which showed superior Lanasol Blue 3R (LB) removal rate to membrane filtration and biodegradation. The modified membranes (MM) exhibited good performance in terms of photocatalytic activity of foulant degradation and mitigation of membrane fouling in a membrane reactor. The obtained MM with (TiO2/PSS)7 exhibited optimal versatility under ultraviolet light irradiation in both dead-end and membrane reactors and superior Lanasol Blue 3R removal rate in membrane filtration and biodegradation. The MM (TiO2/PSS)7 possessed excellent antifouling properties by using bovine serum albumin (BSA), as evidenced by the extended Derjaguin-Landau-Verwey-Overbeek theory. Additionally, the TiO2/PSS membrane showed good self-cleaning ability, and the foulants on the membrane surface could be degraded using ultraviolet light irradiation.


Assuntos
Membranas Artificiais , Eliminação de Resíduos Líquidos , Incrustação Biológica , Filtração , Polivinil , Titânio , Raios Ultravioleta , Águas Residuárias
5.
Redox Biol ; 28: 101355, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677554

RESUMO

Nuclear prelamin A recognition factor-like (NARFL) is a human protein that participates in cytosolic iron-sulfur (Fe-S) protein biogenesis and cellular defense against oxidative stress. Previous studies of Narfl knockout mice did not reveal well the regulatory mechanisms of embryonic development mediated by Narfl because the homozygous mice die in utero. Here, we investigated the function of narfl in an established zebrafish knockout model by taking advantage of zebrafish external fertilization and ease of embryonic development examination. Our experiments showed that narfl deletion resulted in larvae lethality, subintestinal vessel (SIV) malformation and digestive organ defects in the early stages of embryonic development. Biochemical analyses and western blot revealed increased oxidative stress and upregulated hypoxia-inducible factor-1α (HIF-1α) expression in narfl-/- fish. The use of HIF-1α inhibitor 2-methoxyestradiol (2ME2) for the treatment of mutants partially rescued the SIV sprouting. These results suggest that narfl deletion causes increased oxidative stress and subintestinal vessel malformation, which further influence the development of digestive organs and might contribute to the lethality of the narfl knockout fish.

6.
J Sci Food Agric ; 100(1): 168-176, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31471909

RESUMO

BACKGROUND: Removing excessive naturally occurring fluoride from tea and/or infusions is difficult because the process has low efficiency and causes secondary pollution. In this study, a novel electrodialysis (ED) technology was developed. We examined the effect of crucial parameters (electrolyte concentration, operation voltage, ED duration and initial concentration of the tea infusion) on defluoridation performance using a highly efficient ion-exchange membrane with five-compartment cells. RESULTS: The most effective ED system results were obtained at an electrolyte concentration of 10 g kg-1 and operating voltage of 20 V. Moreover, the fluoride removal capacity (10.70-66.93%) was highly dependent on the ED duration (1-15 min) and initial concentration of the tea infusion (0.5-10 g kg-1 ). The longer the ED duration and the lower the initial concentration, the higher was the defluoridation performance. During ED, limited loss of the main inclusions (total polyphenols, catechins, caffeine and selected ions) was observed. Furthermore, the D201 anion resin-filled ED stack (0.5-5 g) and improvement of concentrate compartment electrolyte (≥5 times the dilute compartment electrolyte) in the ED system enhanced the defluoridation rate significantly. CONCLUSION: ED is a potentially effective method that can be used for defluoridation in the deep processing of tea products. © 2019 Society of Chemical Industry.


Assuntos
Diálise/métodos , Fluoretos/química , Manipulação de Alimentos/métodos , Chá/química , Diálise/instrumentação , Fluoretos/isolamento & purificação , Manipulação de Alimentos/instrumentação
7.
Langmuir ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31885276

RESUMO

Because of the unique optical properties of gold nanomaterials, the preparation of gold nanomaterials with excellent chirality has received extensive attention. In order to develop a simple fabrication method for three-dimensional chiral Au nanostructures with a size of several hundred nanometers, chiral gold nanoparticles were developed to transfer chirality of a peptide to gold nanoparticles. In this study, the controlled synthesis of asymmetric gold nanopolyhedrons was achieved. The asymmetric gold nanopolyhedrons prepared via peptide-directed growth can exhibit strong circular dichroism (∼±50 mdeg) couplets in the visible range (500-600 nm). Also, the morphology of chiral Au nanododecahedrons-peptide particles showed distorted and asymmetric properties. In order to prove that the size and spatial structure of gold nanopolyhedrons have an influence on their chiral optical properties, Au nanotrioctahedron-peptide particles were prepared by using Au nanotrioctahedrons with different morphologies. Au nanotrioctahedron-peptide particles also exhibited circular dichromatic couplets in the visible region.

8.
Hepatol Commun ; 3(12): 1642-1655, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31832572

RESUMO

We have recently shown that loss of ß-catenin prevents the development of cholestatic liver injury and fibrosis after bile duct ligation (BDL) due to loss of the inhibitory farnesoid X receptor (FXR)/ß-catenin complex, which results in decreased hepatic bile acids (BAs) through activation of FXR. To further understand the role of Wnt/ß-catenin signaling in regulating BA metabolism and cholestasis, we performed BDL on mice in which hepatocyte Wnt signaling is deficient but ß-catenin is intact (low-density lipoprotein receptor-related protein [LRP]5/6 knockout [DKO]) as well as mice that have enhanced hepatocyte ß-catenin expression (serine 45 mutated to aspartic acid [S45D] transgenic [TG] mice). Despite decreased biliary injury after BDL, hepatic injury, fibrosis, and inflammation were comparable in DKO and wild-type (WT) mice. Notably, the FXR/ß-catenin complex was maintained in DKO livers after BDL, coincident with significantly elevated hepatic BA levels. Similarly, TG mice did not display accelerated injury or increased mortality despite overexpression of ß-catenin. There was no augmentation of FXR/ß-catenin association in TG livers; this resulted in equivalent hepatic BAs in WT and TG mice after BDL. Finally, we analyzed the effect of BDL on ß-catenin activity and identified an increase in periportal cytoplasmic stabilization and association with T-cell factor 4 that correlated with increased expression of distinct downstream target genes. Conclusion: Localization of ß-catenin and expression of Wnt-regulated genes were altered in liver after BDL; however, neither elimination of Wnt/ß-catenin signaling nor overexpression of ß-catenin in hepatocytes significantly impacted the phenotype or progression of BA-driven cholestatic injury.

9.
Viruses ; 11(12)2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31835357

RESUMO

Seoul virus (SEOV), which causes hemorrhagic fever with renal syndrome (HFRS) in humans, has spread all over the world, especially in mainland China. Understanding basic mechanisms of SEOV evolution is essential to better combat and prevent viral diseases. Here, we examined SEOV prevalence and evolution in the residential area of four districts in Guangzhou city, China. The carriage of SEOV was observed in 33.33% of the sampled rodents, with 35.96% of the sampled Rattus norvegicus and 13.33% of R. tanezumi. Based on the comprehensive analyses of large (L), medium (M), and small (S) segments, our study first demonstrated that the genetic characterization of urban SEOV was shaped by high nucleotide substitution rates, purifying selection, and recombination. Additionally, we detected mutational saturation in the S segment of SEOV, which may lead to the biases of genetic divergence and substitution rates in our study. Importantly, we have filled the gap of SEOV evolution in the urban area. The genetic variation of SEOV may highlight the risk of HFRS, which merits further investigation.

10.
Nanomaterials (Basel) ; 9(12)2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31835756

RESUMO

Lead-free double perovskites have been considered as a potential environmentally friendly photovoltaic material for substituting the hybrid lead halide perovskites due to their high stability and nontoxicity. Here, lead-free double perovskite Cs2AgBiBr6 films are initially fabricated by single-source evaporation deposition under high vacuum condition. X-ray diffraction and scanning electron microscopy characterization show that the high crystallinity, flat, and pinhole-free double perovskite Cs2AgBiBr6 films were obtained after post-annealing at 300 °C for 15 min. By changing the annealing temperature, annealing time, and film thickness, perovskite Cs2AgBiBr6 solar cells with planar heterojunction structure of FTO/TiO2/Cs2AgBiBr6/Spiro-OMeTAD/Ag achieve an encouraging power conversion efficiency of 0.70%. Our preliminary work opens a feasible approach for preparing high-quality double perovskite Cs2AgBiBr6 films wielding considerable potential for photovoltaic application.

11.
Neurochem Int ; : 104643, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31837353

RESUMO

Adult hippocampal neurogenesis plays the pivotal roles in central nervous system diseases. Recently, it has been reported that levetiracetam (LEV), a new antiepileptic drug with novel chemical construction and unique pharmacological properties, suppressed aberrant adult subventricular zone (SGZ) neurogenesis in kainite-induced epileptic mice, while promoted adult SGZ neuroblast differentiation in normal mice. These studies indicate LEV can modulate adult hippocampal neurogenesis, but the exact mechanism remained unknown. Thus, the present study aimed to investigate the effects of subchronic and chronic LEV treatments on neural stem cell by lineage tracing in adult hippocampal dentate gyrus of mice, as well as the potential mechanism related to Wnt/ß-catenin signaling pathway. The data showed that both subchronic and chronic LEV treatments had no effects on body weight, locomotor activity and anxiety-like behavior in mice. Notably, subchronic LEV treatment significantly suppressed the proliferation of intermediate progenitor cell and neuroblast, decreased the number of intermediate progenitor cell and neuroblast, but increased the number of quiescent neural stem cell. On the contrary, chronic LEV treatment promoted the proliferation of neural stem cell, intermediate progenitor cell and neuroblast, increased the number of neural stem cell, intermediate progenitor cell and neuroblast, and promoted differentiation of newborn immature neuron and mature neuron. Furthermore, subchronic LEV treatment decreased the level of Wnt 3a and nuclear ß-Catenin expression, which led to the inhibition on Wnt/ß-catenin signaling pathway. Chronic LEV treatment increased the level of Wnt 3a, cytosolic ß-catenin and nuclear ß-Catenin, decreased the expression of GSK-3ß, p-Tyr216-GSK-3ß and Axin2, resulting in the enhancement of Wnt/ß-catenin signaling pathway. These results demonstrated that LEV significantly suppressed or promoted adult hippocampal neurogenesis in mice by subchronic or chronic treatment possibly through the regulation of Wnt/ß-catenin signaling pathway. Our findings provided the new perspectives of LEV on adult hippocampal neurogenesis underlying its clinical application.

12.
Mol Immunol ; 118: 19-29, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31837507

RESUMO

The role of naturally occurring regulatory T cells (Treg) in the control of the immune tolerance of ANCA-associated vasculitis (AAV) has not been well defined. Therefore, we separate the phenotypically heterogeneous Treg cells into different subsets based on the expression of FOXP3 and CD45RA during AAV pathogenesis. Fifty-four AAV patients (38 patients with renal involvement) and 19 healthy controls (HCs) were enrolled in this study. Levels of CD4+T cell subsets and cytokines were detected by flow cytometry. Treg immunesuppression capacity was measured in co-culture experiments. The diagnostic value for Treg subsets was evaluated by the areas under the receiver operating characteristic curves (AUC). Patients with AAV had lower percentages and numbers of activated Treg cells (aTreg, P = 0.044, P = 0.002), while higher levels of total Treg cells (P = 0.001, P = 0.026) with diminished immunosuppression capacity. The proportions of effector memory T-cell subpopulation (P < 0.001) were increased in AAV patients. Interestingly, the AUC of the aTreg improved significantly the diagnostic potential of AAV. Furthermore, the ratio of Th17/aTreg was significantly increased in active and renal vasculitis patient and positive correlation between Th17/Treg subset ratio and creatinine or BUN. In addition, we found that cytokine IL-2 and IL-4 exhibited a downward while IL-6, IL-10, TNF-α, IFN-γ and IL-17A trend upward in AAV patients. Increase in total Treg levels, along with functional deficiency, and decrease in aTreg cells constitute potential novel biomarkers for AAV. And the ratio of Th17/aTreg might serve as an important tool to recognize and monitor AAV patients with renal involvement and disease remission.

13.
J Orthop Surg Res ; 14(1): 417, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31818330

RESUMO

BACKGROUND: Nursing intervention following discharge is a long-term rehabilitation process that is essential for improving hip joint function and quality of life in affected patients. This study aimed to assess the effect of nursing intervention via WeChat on the rehabilitation of patients after total hip arthroplasty (THA). METHODS: We conducted a retrospective analysis of 232 patients who underwent THA at our hospital from January 2013 to October 2015. Of the 232 patients, 114 received nursing intervention via telephone (Group A), and 118 received nursing intervention via WeChat (Group B). Furthermore, the Harris hip score and Short-Form 36 (SF-36) health survey score were used to evaluate hip joint function and quality of life in patients in the two groups at discharge and 1, 3 and 6 months following discharge. Moreover, the functional independence measure was applied to assess the recovery of joint function in the patients. RESULTS: No significant difference was observed in the Harris hip score and the SF-36 health survey score between the two groups at discharge and 1 month following discharge (p > 0.05). However, the Harris hip score and SF-36 health survey score were lower in group A than in group B at 3 and 6 months following discharge (p < 0.05). Furthermore, no obvious difference was observed in terms of functional independence between the two groups at discharge (p > 0.05). However, more individuals were completely independent in group B than in group A at 1, 3 and 6 months following discharge (p < 0.05). CONCLUSIONS: Nursing intervention via WeChat can improve the effect of rehabilitation after THA and promote the recovery of joint function in patients.

14.
Onco Targets Ther ; 12: 9239-9248, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819473

RESUMO

Background: Ovarian cancer is characterized by high metastatic potential and high mortality. More than 80% of primary ovarian malignancies are epithelial ovarian cancers. There is increasing evidence that Speckle-type POZ protein (SPOP) is highly correlated with the development of various types of cancer. However, the effects of SPOP on epithelial ovarian cancer and the associated molecular mechanisms remain unclear. Materials and methods: We compared SPOP expression between epithelial ovarian cancer tissues and normal ovarian tissues by using immunohistochemical staining. To determine the role of SPOP in epithelial ovarian cancer cells, we overexpressed or knocked down SPOP in the epithelial ovarian cancer cell line OVCAR-3 using lentiviral vectors. Results: Our results from the present study indicated that SPOP expression was significantly downregulated in human epithelial ovarian cancer and was associated with the FIGO stage and the histopathologic grading of the tumor. The overexpression and knockdown experiments revealed that SPOP inhibited proliferation while promoting apoptosis in ovarian cancer cells. Inhibition of SPOP mis-activated the Hedgehog (Hh) signaling pathway, thereby inhibiting apoptosis in ovarian cancer cells. Conclusion: SPOP suppresses proliferation and promotes apoptosis in human ovarian cancer cells by inhibiting the Hh signaling pathway, offering the possibility of new approaches for the treatment of ovarian cancer.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31786739

RESUMO

PROPOSE: Poly (ADP-ribose) polymerase 1 inhibitors were originally investigated as anti-cancer therapeutics with BRCA1/2 genes mutation. Here, we investigate the effectiveness of a novel PARP1 inhibitor fluzoparib, for enhancing the radiation sensitivity of NSCLC cells lacking BRCA1/2 mutation. METHODS: We used MTS assays, western blotting, colony formation assays, immunofluorescence staining, and flow cytometry to evaluate the radiosensitization of NSCLC cells to fluzoparib and explore the underlying mechanisms in vitro. Through BRCA1 and RAD50 genes knockdown, we established dysfunctional homologous recombination (HR) DNA repair pathway models in NSCLC cells. We next investigated the radiosensitization effect of fluzoparib in vivo using human NSCLC xenograft models in mice. The expression of PARP1 and BRCA1 in human NSCLC tumor samples was measured by immunohistochemistry. Furthermore, we sequenced HR-related gene mutations and analyzed their frequencies in advanced NSCLC. RESULTS: In vitro experiments in NSCLC cell lines along with in vivo experiments using an NSCLC xenograft mouse model demonstrated the radiosensitization effect of fluzoparib. The underlying mechanisms involved increased apoptosis, cell-cycle arrest, enhanced irradiation-induced DNA damage, and delayed DNA-damage repair. Immunohistochemical staining showed no correlation between the expression of PARP1 and BRCA1. Moreover, our sequencing results revealed high mutation frequencies for the BRCA1/2, CHEK2, ATR, and RAD50 genes. CONCLUSION: The potential therapeutic value of fluzoparib for increasing the radiation sensitivity of NSCLC is well confirmed. Moreover, our findings of high mutation frequencies among HR genes suggest that PARP1 inhibition may be an effective treatment strategy for advanced non-small cell lung cancer patients.

16.
ChemSusChem ; 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31808618

RESUMO

As a promising approach to produce hydrogen, the efficiency of electrolytic overall water splitting is severely limited by the sluggish kinetics of oxygen evolution reaction (OER) and low activity of electrocatalysts at present. To solve these problems, in addition to developing efficient precious metal catalysts, a more effective strategy is proposed to replace OER by selective methanol oxidation reaction. Nickel-cobalt hydroxides (Ni x Co 1-x (OH) 2 ) nanoarrays are obtained through a facile hydrothermal treatment as bifunctional electrocatalysts for co-electrolysis of methanol-water to simultaneously co-produce H 2 and value-added formate. The electrocatalysts could catalyze methanol selective oxidation (~ 1.32 V) with significantly lower energy consumption (~ 0.2 V less) compared with oxygen evolution. And more importantly, methanol is exclusively transformed to value-added formate with a high Faradaic efficiency (selectivity) close to 100%. Specifically, the cell voltage of only ~ 1.5 V is required to generate a current density of 10 mA cm -2 . Furthermore, the Ni 0.33 Co 0.67 (OH) 2 /NF nanoneedle arrays also present an outstanding stability for overall co-electrolysis.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31855281

RESUMO

EZH2 (Enhancer of zeste homolog 2) regulates epigenetic gene silencing and functions as critical regulators in various tumor progression. Macrophages infiltration promotes cancer development via stimulating tumor cell migration and invasion. However, the effect of EZH2 on macrophages infiltration, cell invasion and migration of lung cancer remains to be investigated. In this study, we found that knockdown of EZH2 inhibited macrophages chemotaxis and decreased chemokine ligand 5 (CCL5). Wound-healing and transwell assays results showed that migration and invasion of lung cancer cells was inhibited by EZH2 deletion. Moreover, EZH2 over-expression increased CCL5 expression. Loss-of functional assay indicated that the promotion ability of EZH2 on macrophages chemotaxis was inhibited by CCL5 knockdown. Mechanistically, the promotion ability of EZH2 on cell migration and invasion of lung cancer was also inhibited by CCL5 knockdown. In vivo subcutaneous xenotransplanted tumor model also revealed that silence of EZH2 suppressed lung cancer metastasis and macrophages infiltration via regulation of CCL5. In conclusion, our findings indicated that EZH2 promoted lung cancer metastasis and macrophages infiltration via up-regulation of CCL5, which might be the underlying mechanism of EZH2-induced lung cancer cell progression. This article is protected by copyright. All rights reserved.

18.
Emerg Microbes Infect ; 8(1): 377-380, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31851878

RESUMO

Highly pathogenic avian influenza (HPAI) is a persistent threat to poultry, wild birds, humans, and other mammals. The continually evolving HPAI H5N6 virus has induced great losses in breeding industries in growing regions around the world. In this study, we confirmed an outbreak of the HPAI H5N6 virus in captive Pavo cristatus in Jiangxi Province, China. The causative agents H5N6 viruses were isolated and designated JS01, JS02, and K10. Animal experiments showed that all three isolates exhibited high pathogenicity to chickens, but they need adaption to effectively infect mice. A phylogenetic analysis showed that all three isolates were clustered in H5 clade 2.3.4.4c. No novel genetic reassortant was found in JS01, JS02, and K10 viruses. It was estimated that JS01, JS02, and K10 H5N6 viruses were direct descendants of the H5N6 virus circulating in South of China. The estimated divergence time from tMRCAs was anywhere between May 2014 to June 2016. Although the number of outbreaks of avian influenza decreased significantly in 2018, the threat from avian influenza to public health remains serious. Enhanced active surveillance is required to monitor the transmission and evolution of H5 influenza viruses.

19.
Mycologia ; : 1-12, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31846602

RESUMO

The genus Magnaporthiopsis of Magnaporthaceae (Magnaporthales, Sordariomycetes, Ascomycota) contains species that are predominantly necrotrophic pathogens, often producing simple hyphopodia and dark, ectotrophic runner hyphae on plant roots and stems during colonization. Fungal isolates from turfgrass roots with dark and ectotrophic runner hyphae were examined and identified based on morphological, biological, and phylogenetic analyses. Maximum likelihood and Bayesian methods were implemented to obtain phylogenetic trees for partial sequences of the 18S nuc rDNA, ITS1-5.8S-ITS2 nuc rDNA internal transcribed spacer, and 28S nuc rDNA regions, and of the minichromosome maintenance complex 7 (MCM7), largest subunit of RNA polymerase II (RPB1), and translation elongation factor 1-alpha (TEF1) genes. Our isolates consistently formed a distinct and highly supported clade within Magnaporthiopsis. These findings were reinforced by common and distinctive biological and morphological characters. Additionally, we conducted pathogenicity evaluations and demonstrated the ability of this fungus to colonize roots of ultradwarf bermudagrass, one of its native hosts, via ectotrophic, dark runner hyphae, causing disease symptoms including root discoloration and reduced root and shoot mass. Altogether, our discoveries enabled recognition and description of a new species, Magnaporthiopsis cynodontis, which has widespread distribution in the United States.

20.
Environ Sci Technol ; 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31880153

RESUMO

Chloromethane (CH3Cl) is an important source of chlorine in the stratosphere, but detailed knowledge of the magnitude of its sources and sinks is missing. Here we measured the stable chlorine isotope fractionation (εCl) associated with the major abiotic and biotic CH3Cl sinks in the environment, namely CH3Cl degradation by hydroxyl (·OH) and chlorine (·Cl) radicals in the troposphere, and by reference bacteria Methylorubrum extorquens CM4 and Leisingera methylohalidivorans MB2 from terrestrial and marine environments, respectively. No chlorine isotope fractionation was detected for reaction of CH3Cl with ·OH and ·Cl radicals, whereas large chlorine isotope fractionation (εCl) of -10.9 ± 0.7‰ (n=3) and -9.4 ± 0.9 (n=3) was found for CH3Cl degradation by M. extorquens CM4 and L. methylohalidivorans MB2, respectively. The large difference in chlorine isotope fractionation observed between tropospheric and bacterial degradation of CH3Cl provides an effective isotopic tool to characterize and distinguish between major abiotic and biotic processes contributing to the CH3Cl sink in the environment. Finally, our findings demonstrate the potential of emerging triple-element isotopic approaches including chlorine to carbon and hydrogen analysis for the assessment of global cycling of organochlorines.

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