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1.
Biomed Mater ; 19(3)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38626779

RESUMEN

It is well-established that multi-scale porous scaffolds can guide axonal growth and facilitate functional restoration after spinal cord injury (SCI). In this study, we developed a novel mussel shell-inspired conductive scaffold for SCI repair with ease of production, multi-scale porous structure, high flexibility, and excellent biocompatibility. By utilizing the reducing properties of polydopamine, non-conductive graphene oxide (GO) was converted into conductive reduced graphene oxide (rGO) and crosslinkedin situwithin the mussel shells.In vitroexperiments confirmed that this multi-scale porous Shell@PDA-GO could serve as structural cues for enhancing cell adhesion, differentiation, and maturation, as well as promoting the electrophysiological development of hippocampal neurons. After transplantation at the injury sites, the Shell@PDA-GO provided a pro-regenerative microenvironment, promoting endogenous neurogenesis, triggering neovascularization, and relieving glial fibrosis formation. Interestingly, the Shell@PDA-GO could induce the release of endogenous growth factors (NGF and NT-3), resulting in the complete regeneration of nerve fibers at 12 weeks. This work provides a feasible strategy for the exploration of conductive multi-scale patterned scaffold to repair SCI.


Asunto(s)
Materiales Biocompatibles , Bivalvos , Grafito , Regeneración Nerviosa , Polímeros , Traumatismos de la Médula Espinal , Andamios del Tejido , Animales , Traumatismos de la Médula Espinal/terapia , Andamios del Tejido/química , Porosidad , Grafito/química , Polímeros/química , Materiales Biocompatibles/química , Indoles/química , Exoesqueleto/química , Diferenciación Celular , Conductividad Eléctrica , Neuronas , Ratas , Ratas Sprague-Dawley , Adhesión Celular , Neurogénesis , Ingeniería de Tejidos/métodos , Factor de Crecimiento Nervioso/metabolismo , Factor de Crecimiento Nervioso/química , Hipocampo
2.
Plant Dis ; 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38568844

RESUMEN

Tobacco (Nicotiana tabacum L.) belongs to the family Solanaceae, an economically significant crop (Zhou et al. 2023). Twelve samples with leaf spots were collected in Keti Village, Changshun County, Zunyi City, Guizhou province, China in 2022. Twenty-five percent of the samples had dry lesions near the leaf tip which resulted leaf tip blight after development. Fungi were isolated by a previous method (Wei et al. 2022). Six Alternaria strains were obtained and preserved in the Fungal Herbarium of Yangtze University (YZU), Jingzhou, Hubei, China. Among them, one strain YZU 221477 showed distinct cultural characteristics out of five A. alternata strains, which was again determined by growing on potato dextrose agar (PDA) at 25°C for 7 days in dark to evaluate. The colonies (60 mm in diameter) were white cottony in the center surrounded by vinaceous purple. To examine the morphology, mycelia were inoculated onto potato carrot agar (PCA) at 22°C, following an 8 h light/16 h dark photoperiod (Simmons 2007). Conidia were obclavate or ovoid, normally 3-5 conidial units per chain, 20-38 × 10-16.5 µm, 3 to 5 transverse septa, beakless or a short beak (4-30 µm). The observation results were consistent with those of A. gossypina (Zhang 2003). Total genomic DNA was extracted using the CTAB method and seven gene regions including internal transcribed spacer of rDNA (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), translation elongation factor 1 alpha (TEF1), RNA polymerase second largest subunit (RPB2), Alternaria major allergen gene (Alt a 1), endopolygalacturonase (EndoPG) and an anonymous gene region (OPA10-2) were amplified with ITS5/ITS4, gpd1/gpd2, EF1-728F/EF1-986R, RPB2-5F/RPB2-7cR, Alt-for/Alt-rev, PG3/PG2b and OPA10-2L/OPA10-2R primers, respectively. All sequences were deposited in GenBank (ITS: OR710806; GAPDH: PP057862; TEF1: PP158601; RPB2: PP057863; Alt a 1: PP057865; EndoPG: PP057861; OPA10-2: PP057864). Combining with relevant sequences retrieved from the NCBI database were used for the phylogenetic analysis. Maximum Likelihood (ML) tree was constructed with RAxML v.7.2.8 employing GTRCAT model using 1000 bootstrap (BS) replicates to assess statistical support. The results indicated that the present strain grouped with A. gossypina (type strain of CBS 104.32) supported with 73% bootstrap values, also having a support of 0.83 Bayesian posterior probabilities values. Based on morphology and molecular evidence, the strain YZU 221477 is identified as Alternaria gossypina. Pathogenicity was examined to fulfill Koch's postulates. Mycelial plugs (6 mm diameter) of the present strain and A. alternata cultivated on PDA were taken from the margin and inoculated onto viable tobacco leaves (Cultivar: Yunyan 87, n=3) growing forty days, while controls were inoculated with sterile PDA. The assay was conducted three times. The plants were maintained at 25°C with humidity levels over 85% in a greenhouse. Leaves were evaluated after 7 days, necrotic spots encircled by yellow halos were on both inoculums, except controls. Pathogen re-isolation confirmed that it was the same as inoculated fungus based on morphology. A. gossypina was firstly found on cotton (Hopkins 1931), late reported to induce disease on Minneola, Nopalea, Hibiscus, Citrus, Solanum and Ageratina. To our knowledge, this is the first report of A. gossypina causing tobacco leaf tip blight in China, and it also provides a basis for controlling of tobacco leaf tip blight.

3.
Front Oncol ; 13: 1274048, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37876967

RESUMEN

With the development of immunotherapy, the process of tumor treatment is also moving forward. Polysaccharides are biological response modifiers widely found in plants, animals, fungi, and algae and are mainly composed of monosaccharides covalently linked by glycosidic bonds. For a long time, polysaccharides have been widely used clinically to enhance the body's immunity. However, their mechanisms of action in tumor immunotherapy have not been thoroughly explored. Dendritic cells (DCs) are a heterogeneous population of antigen presenting cells (APCs) that play a crucial role in the regulation and maintenance of the immune response. There is growing evidence that polysaccharides can enhance the essential functions of DCs to intervene the immune response. This paper describes the research progress on the anti-tumor immune effects of natural polysaccharides on DCs. These studies show that polysaccharides can act on pattern recognition receptors (PRRs) on the surface of DCs and activate phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT), mitogen-activated protein kinase (MAPK), nuclear factor-κB (NF-κB), Dectin-1/Syk, and other signalling pathways, thereby promoting the main functions of DCs such as maturation, metabolism, antigen uptake and presentation, and activation of T cells, and then play an anti-tumor role. In addition, the application of polysaccharides as adjuvants for DC vaccines, in combination with adoptive immunotherapy and immune checkpoint inhibitors (ICIs), as well as their co-assembly with nanoparticles (NPs) into nano drug delivery systems is also introduced. These results reveal the biological effects of polysaccharides, provide a new perspective for the anti-tumor immunopharmacological research of natural polysaccharides, and provide helpful information for guiding polysaccharides as complementary medicines in cancer immunotherapy.

4.
World J Clin Cases ; 11(27): 6455-6475, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37900219

RESUMEN

BACKGROUND: Radical resection offers the only hope for the long-term survival of patients with gallbladder carcinoma (GBC) above the T1b stage. However, whether it should be performed under laparoscopy for GBC is still controversial. AIM: To compare laparoscopic radical resection (LRR) with traditional open radical resection (ORR) in managing GBC. METHODS: A comprehensive search of online databases, including Medline (PubMed), Cochrane Library, and Web of Science, was conducted to identify comparative studies involving LRR and ORR in GBCs till March 2023. A meta-analysis was subsequently performed. RESULTS: A total of 18 retrospective studies were identified. In the long-term prognosis, the LRR group was comparable with the ORR group in terms of overall survival and tumor-free survival (TFS). LRR showed superiority in terms of TFS in the T2/tumor-node-metastasis (TNM) Ⅱ stage subgroup vs the ORR group (P = 0.04). In the short-term prognosis, the LRR group had superiority over the ORR group in the postoperative length of stay (POLS) (P < 0.001). The sensitivity analysis showed that all pooled results were robust. CONCLUSION: The meta-analysis results show that LRR is not inferior to ORR in all measured outcomes and is even superior in the TFS of patients with stage T2/TNM Ⅱ disease and POLS. Surgeons with sufficient laparoscopic experience can perform LRR as an alternative surgical strategy to ORR.

5.
Front Plant Sci ; 14: 1199956, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37828924

RESUMEN

Epicoccum latusicollum is a fungus that causes a severe foliar disease on flue-cured tobacco in southwest China, resulting in significant losses in tobacco yield and quality. To better understand the organism, researchers investigated its optimal growth conditions and metabolic versatility using a combination of traditional methods and the Biolog Phenotype MicroArray technique. The study found that E. latusicollum exhibited impressive metabolic versatility, being able to metabolize a majority of carbon, nitrogen, sulfur, and phosphorus sources tested, as well as adapt to different environmental conditions, including broad pH ranges and various osmolytes. The optimal medium for mycelial growth was alkyl ester agar medium, while oatmeal agar medium was optimal for sporulation, and the optimum temperature for mycelial growth was 25°C. The lethal temperature was 40°C. The study also identified arbutin and amygdalin as optimal carbon sources and Ala-Asp and Ala-Glu as optimal nitrogen sources for E. latusicollum. Furthermore, the genome of E. latusicollum strain T41 was sequenced using Illumina HiSeq and Pacific Biosciences technologies, with 10,821 genes predicted using Nonredundant, Gene Ontology, Clusters of Orthologous Groups, Kyoto Encyclopedia of Genes and Genomes, and SWISS-PROT databases. Analysis of the metabolic functions of phyllosphere microorganisms on diseased tobacco leaves affected by E. latusicollum using the Biolog Eco microplate revealed an inability to efficiently metabolize a total of 29 carbon sources, with only tween 40 showing some metabolizing ability. The study provides new insights into the structure and function of phyllosphere microbiota and highlights important challenges for future research, as well as a theoretical basis for the integrated control and breeding for disease resistance of tobacco Epicoccus leaf spot. This information can be useful in developing new strategies for disease control and management, as well as enhancing crop productivity and quality.

6.
ACS Nano ; 17(20): 20246-20261, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37782701

RESUMEN

Restoring damaged myocardial tissue with therapeutic exogenous cells still has some limitations, such as immunological rejection, immature cardiac properties, risk of tumorigenicity, and a low cell survival rate in the ischemic myocardium microenvironment. Activating the endogenous stem cells with functional biomaterials might overcome these limitations. Research has highlighted the multiple differentiation potential of epicardial cells via epithelial-mesenchymal transition (EMT) in both heart development and cardiac regeneration. In our previous research, a carboxylic gelatin-methacrylate (carbox-GelMA) nanoparticle (NP) was fabricated to carry ammonium persulfate (APS), and APS-loaded carbox-GelMA NPs (NPs/APS) could drive the EMT of MCF-7 cells in vitro and promote cancer cell migration and invasion in vivo. The present study explored the roles of functional NPs/APS in the EMT of Wilms' tumor 1-positive (WT1+) epicardial cells and in the repair of myocardial infarction (MI). The WT1+ epicardial cells transformed into endothelial-like cells after being treated with NPs/APS in vitro, and the cardiac functions were improved significantly after injecting NPs/APS into the infarcted hearts in vivo. Furthermore, simultaneous activation of both autophagy and the mTOR pathway was confirmed during the NPs/APS-induced EMT process in WT1+ epicardial cells. Together, this study highlights the function of NPs/APS in the repair of MI.


Asunto(s)
Infarto del Miocardio , Nanopartículas , Humanos , Transición Epitelial-Mesenquimal , Gelatina , Metacrilatos , Infarto del Miocardio/patología , Serina-Treonina Quinasas TOR , Autofagia
7.
BMC Pregnancy Childbirth ; 23(1): 604, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37612626

RESUMEN

BACKGROUD: To investigate the effect of Luteinizing hormone (LH) level changes on the outcomes of controlled ovarian hyperstimulation (COH) and embryo transfer (ET) in gonadotropin-releasing hormone antagonist (GnRH-ant) protocol. METHODS: A total of 721 patients undergoing GnRH-ant protocol COH for the first IVF/ICSI cycles were retrospectively analyzed. COH process were divided into 2 stages, before (stage 1) and after (stage 2) the GnRH-ant initiation, and each with 5 groups basing on LH levels: LH decreased more than 50% (groups A1, A2), decreased 25-50% (groups B1, B2), change less than 25% (groups C1, C2), increased 25-50% (groups D1, D2), and increased more than 50% (groups E1, E2). RESULTS: There were no significant differences among groups of stage1 regarding COH and ET outcomes. For stage 2, the more obvious the decrease of LH level, the more the number of oocytes retrieved, mature oocytes, fertilized oocytes, embryos cleavaged and the numbers of embryo available (P < 0.05), but without significant differences regarding ET outcomes. We also found the freeze-all rate in Group A2 was higher (P < 0.001). CONCLUSION: LH level changes before GnRH-ant addition were not related to COH and ET outcomes. LH level changes after the addition of GnRH-ant were related to the outcome of COH, and no significant differences were found relating to ET outcomes.


Asunto(s)
Hormona Luteinizante , Oocitos , Humanos , Estudios Retrospectivos , Transferencia de Embrión , Antagonistas de Hormonas/uso terapéutico , Hormona Liberadora de Gonadotropina
8.
Plant Dis ; 2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37415353

RESUMEN

Macleaya cordata is a perennial herb that belongs to the Papaveraceae and is typically prescribed as a traditional antibacterial medicine in China (Kosina et al. 2010). The extract from M. cordata has been widely used in the manufacturing of natural growth promoters as an alternative to antibiotic growth promoters in the livestock industry (Liu et al. 2017), and the products are marketed in 70 countries such as Germany, China, etc (Ikezawa et al. 2009). During the summer of 2019, symptoms of leaf spot were observed on M. cordata (cv. HNXN-001) in two commercial fields (approximately 1, 300 m2 and 2, 100 m2) of Xinning county, Shaoyang City, Hunan Province, China, where approximately 2 to 3% of the plants were affected. The initial symptoms were irregular black and brown spots on the leaves. The lesions expanded and coalesced, eventually leading to leaf blight. Six symptomatic basal leaf sections from six plants from two fields were surface disinfested in 0.5% NaClO for 1 min, then 75% ethanol for 20 s, rinsed in sterile water three times, air dried, and placed onto potato dextrose agar (PDA), one dish for samples from a single leaf. Plates were incubated at 26°C in darkness. Nine strains with similar morphological characters were isolated, and one representative isolate ( BLH-YB-08) was used for morphological and molecular characterization. The colonies on PDA were grayish-green with white round margins. Conidia were typically obclavate to obpyriform, brown to dark brown, and 12.0 to 35.0 × 6.0 to 15.0 µm, and with 1 to 5 transverse septa and 0 to 2 longitudinal septa (n=50). Isolates were identified as Alternaria sp. on the basis of mycelial characteristics, color, and conidial morphology. To confirm identity of the pathogen, DNA was extracted from isolate BLH-YB-08 with the DNAsecure Plant Kit (TIANGEN, Biotech, China). The glyceraldehyde-3-phosphate dehydrogenase (GAPDH), RNA polymerase II second largest subunit (RPB2), actin (ACT), 28S nrDNA (LSU), 18S nuclear ribosomal DNA (SSU), histone 3 (HIS3), internal transcribed spacer (ITS) region of ribosomal DNA, and translation elongation factor 1-α (TEF) genes ( Berbee et al. 1999; Carbone and Kohn. 1999; Glass and Donaldson. 1995; White et al. 1990.) were amplified and sequenced. Sequences were deposited into the GenBank database. They were 100% sequence identity of GAPDH (OQ224996) with A. alternata strain AA2-8 (MH65578; 578/578bp), 100% sequence identity of RPB2 (OQ190460) with A. alternata strain SAX-WN-30-2 ( MK605877; 933/933bp), 100% sequence identity of ACT (OQ923292) with A. alternata strain FCBP0352 (OL830257; 939/939 bp), 100% sequence identity of LSU (OQ891167) with A. alternata XL14 (MG839509 ; 908/908 bp), 100% sequence identity of SSU (OQ139544) with A. alternata strain BJ19.4.1(OM736063; 1,067/1,067 bp), 100% sequence identity of HIS3 (MT454856) with A. alternata YJ-CYC-HC2 (OQ116440 ; 442/442 bp), 100% sequence identity of ITS (MT212225) with A. alternata CS-1-3 (OQ947366; 543/543bp), and 100% sequence identity of TEF (OQ190461) with A. alternata strain YZU 221185 (OQ512730; 252/252 bp). To test pathogenicity, the isolate BLH-YB-08 was cultured on PDA for 7 days to prepare conidial suspensions and the spore concentration adjusted to a final concentration of 1×106 spores/ml. The leaves of five potted 45-day-old M. cordata (cv. HNXN-001) plants were sprayed with conidial suspensions, and five control potted plants were wiped with 75% alcohol and washed five times with sterile distilled water. They were then sprayed with sterile distilled water. Plants were placed in a greenhouse at 25 to 30°C with 90% relative humidity. Pathogenicity tests were conducted twice. Fifteen days after inoculation, lesions were found on inoculated leaves, and the symptoms were the same as those in the field, whereas the controls were healthy. A fungus was consistently isolated from the inoculated leaves and identified as A. alternata by DNA sequencing of the GAPDH, ITS, and HIS3 genes, fulfilling Koch's postulates. To our knowledge, this is the first report of leaf spot on M. cordata caused by A. alternata in China. Understanding its etiology may help to control this fungal pathogen, thus reducing economic losses. Funding: Hunan Provincial Natural Science Foundation General Project (2023JJ30341) Hunan Provincial Natural Science Foundation Youth Fund (2023JJ40367) Seed Industry Innovation Project of Hunan Provincial Science and Technology Department Special project for the construction of Chinese herbal medicine industry technology system in Hunan Province "Xiangjiuwei" Industrial Cluster Project of the Ministry of Agriculture and Rural Affairs.

9.
Research (Wash D C) ; 6: 0161, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37303598

RESUMEN

The biomimetic construction of a microstructural-mechanical-electrical anisotropic microenvironment adaptive to the native cardiac tissue is essential to repair myocardial infarction (MI). Inspired by the 3D anisotropic characteristic of the natural fish swim bladder (FSB), a novel flexible, anisotropic, and conductive hydrogel was developed for tissue-specific adaptation to the anisotropic structural, conductive, and mechanical features of the native cardiac extracellular matrix. The results revealed that the originally stiff, homogeneous FSB film was tailored to a highly flexible anisotropic hydrogel, enabling its potential as a functional engineered cardiac patch (ECP). In vitro and in vivo experiments demonstrated the enhanced electrophysiological activity, maturation, elongation, and orientation of cardiomyocytes (CMs), and marked MI repair performance with reduced CM apoptosis and myocardial fibrosis, thereby promoting cell retention, myogenesis, and vascularization, as well as improving electrical integration. Our findings offer a potential strategy for functional ECP and provides a novel strategy to bionically simulate the complex cardiac repair environment.

10.
Biomater Sci ; 11(9): 3227-3240, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-36935633

RESUMEN

Injectable self-healing hydrogel dressings with excellent elasticity and multifunctional repair effects have been in high demand in wound healing applications, while maintaining stable elasticity in injectable multifunctional hydrogel dressings is still a challenge. Based on carboxymethyl chitosan (CMCS), curcumin-gelatin nanoparticles (CG NPs), and sodium alginate oxide (OSA), we developed a double-crosslinking injectable elastic self-healing hydrogel without any chemical cross-linking agent as a multifunctional wound healing dressing. CG NPs were more stable than pure curcumin (Cur) nanoparticles and could regulate the cross-linking of injectable hydrogels for high elasticity and rapid self-healing. We found that the CG NPs endowed the injectable hydrogel with good anti-inflammatory, antibacterial, and reactive oxygen scavenging activities and could significantly shorten the wound healing time in infected full-thickness skin defect rats by promoting the polarization of M2-type macrophages, reducing oxidative damage, accelerating collagen deposition, enhancing granulation formation, and elevating angiogenesis. Taken together, the tunable elastic injectable hydrogel dressing exhibited a long-term service life with sustained repair function and can be taken as an optimal candidate for bacteria-infected wound healing.


Asunto(s)
Quitosano , Curcumina , Nanopartículas , Ratas , Animales , Hidrogeles/farmacología , Cicatrización de Heridas , Gelatina/farmacología , Curcumina/farmacología , Curcumina/uso terapéutico , Vendajes , Antibacterianos/farmacología , Quitosano/farmacología
11.
J Am Chem Soc ; 145(13): 7301-7312, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36940192

RESUMEN

Catalyst design has traditionally focused on rigid structural elements to prevent conformational flexibility. Ishihara's elegant design of conformationally flexible C2-symmetric iodoarenes, a new class of privileged organocatalysts, for the catalytic asymmetric dearomatization (CADA) of naphthols is a notable exception. Despite the widespread use of the Ishihara catalysts for CADAs, the reaction mechanism remains the subject of debate, and the mode of asymmetric induction has not been well established. Here, we report an in-depth computational investigation of three possible mechanisms in the literature. Our results, however, reveal that this reaction is best rationalized by a fourth mechanism called "proton-transfer-coupled-dearomatization (PTCD)", which is predicted to be strongly favored over other competing pathways. The PTCD mechanism is consistent with a control experiment and further validated by applying it to rationalize the enantioselectivities. Oxidation of the flexible I(I) catalyst to catalytic active I(III) species induces a defined C2-symmetric helical chiral environment with a delicate balance between flexibility and rigidity. A match/mismatch effect between the active catalyst and the substrate's helical shape in the dearomatization transition states was observed. The helical shape match allows the active catalyst to adapt its conformation to maximize attractive noncovalent interactions, including I(III)···O halogen bond, N-H···O hydrogen bond, and π···π stacking, to stabilize the favored transition state. A stereochemical model capable of rationalizing the effect of catalyst structural variation on the enantioselectivities is developed. The present study enriches our understanding of how flexible catalysts achieve high stereoinduction and may serve as an inspiration for the future exploration of conformational flexibility for new catalyst designs.

12.
Adv Mater ; 35(9): e2209497, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36527726

RESUMEN

It is challenging to balance high biocompability with good mechanical-electrical sensing performance, especially when triggering inflammatory stress response after in vivo implantation. Herein, a bioinspired wrinkle-reinforced adaptive nanoclay-interlocked soft strain-sensor based on a highly stretchable and elastic ionic-conductive hydrogel is reported. This novel nanoclay-composite hydrogel exhibits excellent tensile properties and high sensing capacity with steady and reliable sensing performance due to the structural-mechanical-electrical integrity of the nanoclay crosslinked and nano-reinforced interpenetrating network. The incorporation of amphiphilic ions provides the hydrogel with significant protein resistance, reducing its non-specific adsorption to proteins upon implantation, improving its biosafety as an implanted device, and maintaining the authenticity of the sensing results. Based on the revealed sensing enhanced mechanism based on hierarchical ordered structures as a proof-of-concept application, this hydrogel sensor is demonstrated to be able to accurately localize the region where myocardial infarction occurs and may become a novel strategy for real-time monitoring of pathological changes in heart disease.


Asunto(s)
Hidrogeles , Infarto del Miocardio , Humanos , Hidrogeles/química , Infarto del Miocardio/patología , Conductividad Eléctrica
13.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-981376

RESUMEN

In Zherong county, Fujian province, the black spot of Pseudostellaria heterophylla often breaks out in the rainy season from April to June every year. As one of the main leaf diseases of P. heterophylla, black spot seriously affects the yield and quality of the medicinal material. To identify and characterize the pathogens causing black spot, we isolated the pathogens, identified them as a species of Alternaria according to Koch's postulates, and then tested their pathogenicity and biological characteristics. The results showed that the pathogens causing P. heterophylla black spot were A. gaisen, as evidenced by the similar colony morphology, spore characteristics, sporulation phenotype, and the same clade with A. gaisen on the phylogenetic tree(the maximum likelihood support rate of 100% and the Bayesian posterior probability of 1.00) built based on the tandem sequences of ITS, tef1, gapdh, endoPG, Alta1, OPA10-2, and KOG1077. The optimum conditions for mycelial growth of the pathogen were 25 ℃, pH 5-8, and 24 h dark culture. The lethal conditions for mycelia and spores were both treatment at 50 ℃ for 10 min. We reported for the first time the A. gaisen-caused black spot of P. heterophylla. The results could provide a theoretical basis for the diagnosis and control of P. heterophylla leaf spot diseases.


Asunto(s)
Teorema de Bayes , Filogenia , Caryophyllaceae , Alternaria , Micelio
14.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-970500

RESUMEN

Violet root rot is one of the main root diseases in the production process of Pseudostellaria heterophylla. To clarify the pathogenic species that cause the violet root rot of P. heterophylla in Fujian province, the roots and the sclerotia with violet root rot symptoms were collected from the main producing areas of P. heterophylla(Fujian province) from 2017 to 2021, and the pathogens were isolated by tissue separation method and identified by morphology and multi-gene phylogenetic analysis. Additionally, the biological characteristics of the pathogens were studied and the fungicides were determined. The results showed that 78 strains of violet root rot were isolated from the collected root samples, which belonged to one type after preliminary morphological identification. Two represen-tative strains were selected from the pathogens for multi-gene phylogenetic analysis, and they were clustered with Helicobasidium mompa together. The suitable culture conditions for the mycelium were OA medium, 25 ℃, pH 6, and ammonium oxalate as the nitrogen source. The lethal temperature of the mycelium was 50 ℃ for 10 minutes. Moreover, 99.1% propiconazole and 98.7% azoxystrobin had the optimal bacteriostatic effect, and the concentrations with the 50% bacteriostatic rate were 16.85 and 12.24 μg·mL~(-1), respectively. On the basis of the above results, the pathogen causing violet root rot of P. heterophylla in Fujian province was H. mompa. The medium type, growth temperature, pH value, nitrogen source, etc. had significant effect on the growth of mycelium.


Asunto(s)
Raíces de Plantas , Filogenia , Temperatura , Caryophyllaceae , Nitrógeno
15.
Chinese Journal of Stomatology ; (12): 398-403, 2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-986085

RESUMEN

Compared with traditional prosthodontic methods, digital prosthodontic technology greatly simplifies the treatment process of patients and improves the accuracy of prosthesis. The fully digital workflow is becoming an important direction of the development of fixed prosthodontics. It can not only effectively improve the efficiency, accuracy and predictability of prosthodontics, but also help the cooperation between multiple disciplines to ensure the systematic treatment. This article systematically discusses the concept process, key technology, material progress and application of completely digital prosthodontic process, as well as the remaining problems, in order to provide reference for its clinical application.

16.
Front Microbiol ; 13: 1068158, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36466663

RESUMEN

In recent years, STROBY (50% Kresoxim-methyl) has been widely used to control tobacco brown spot in Guizhou Province, China. As a broad-spectrum fungicide, STROBY targets not only phytopathogens, but also affects many other microorganisms including those pathogenic, beneficial, or neutral to the plant hosts. To understand the effects of STROBY on the phyllosphere microbial communities of tobacco leaves during the development of tobacco brown spot, the fungal and bacterial communities of symptomatic and asymptomatic leaves at four time points, before spraying (August 29) and after spraying (September 3, 8, and 13), were investigated using the Illumina high-throughput sequencing. The results showed that STROBY had significant effects on the phyllosphere microbial communities of tobacco leaves. Microbial communities in asymptomatic leaves were more greatly affected than their counterparts in symptomatic leaves, and fungal communities were more sensitive than bacterial communities. Throughout the experiment, the most common genera in symptomatic leaves were Alternaria, Pseudomonas, Pantoea, and Sphingomonas, and in asymptomatic leaves, these were Golubevia and Pantoea. After spraying, the alpha diversity of fungal communities increased in symptomatic leaves and decreased in asymptomatic leaves, while the alpha diversity of bacteria increased in both types of leaves. Beta diversity showed that in asymptomatic leaves, the fungal communities in the first stage was significantly different from the remaining three stages. In contrast, the fungal communities in symptomatic leaves and the bacterial communities in all leaves did not fluctuate significantly during the four stages. Before spraying (August 29), the dominant functions of the fungal community were animal pathogen, endophyte, plant pathogen, and wood saprotroph. Whereas after spraying (September 3, 8, and 13), the proportion of the above fungal functions decreased and the unassigned functions increased, especially in asymptomatic leaves. This study describes the effects of STROBY application and tobacco brown spot presence in shaping the leaf phyllosphere microbial communities, and provides insights into the microbial community effects on tobacco leaves of a strobilurin fungicide.

17.
Fa Yi Xue Za Zhi ; 38(4): 486-489, 2022 Aug 25.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-36426692

RESUMEN

OBJECTIVES: To analyze the characteristics of thoracic aorta injury in road traffic accidents, to provide data reference for forensic identification. METHODS: The data of 27 traffic accident death cases with thoracic aorta injury were analyzed according to relevant parameters including sex, age, mode of transportation, and thoracic aorta injury. RESULTS: Aortic injury in traffic accidents was significantly more in males than females, and 74.1% cases were in the age range of 31-70 years. The most common mode of transportation was the motorcycle, followed by electric bike, most of which crashed with trucks. Most cases were accompanied by rib fractures and lung injuries. Thoracic aorta injury was the most common in ascending aorta, followed by aortic arch and thoracic aorta. Ascending aorta injury was most likely to occur in the range of 0-<1.6 cm from the aortic valve, while it was rare over 2.6 cm. Taking the aortic valve as the reference, the most common locations of injury were the anterior semilunar valve, followed by the right posterior semilunar valve and the left posterior semilunar valve. Thoracic aortic rupture occurred in 63.0% cases, and intima and media lacerations only occurred in 37.0% cases. A few deceased had aortic diseases. CONCLUSIONS: The proximal part of the ascending aorta is prone to be injured because of the large external force of traffic accidents. The medical examiner should carefully examine the aortic injury in traffic accident deaths, and evaluate the relationship between the injury and the disease according to the condition and degree of aortic injury.


Asunto(s)
Rotura de la Aorta , Fracturas de las Costillas , Traumatismos Torácicos , Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Aorta Torácica/lesiones , Accidentes de Tránsito , Rotura de la Aorta/etiología
18.
Eur J Pharm Biopharm ; 180: 212-223, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36265828

RESUMEN

Amplification of intracellular oxidative stress has been found to be an effective strategy to induce cancer cell death. Herein, the effect of a disulfide, 2,2'-dithiobis(5-aminopyridine) (BAPS), is revealed on depleting glutathione (GSH) circularly and generating superoxide anion (O2•-) spontaneously to manipulate intracellular redox homeostasis. Thus, BAPS is able to work as an oxidative stress amplifier in cancer cells with high GSH concentrations and kill them efficiently. Moreover, leveraging a new class of water-soluble fluoropolymers poly(N-(2-((2,2,2-trifluoroethyl)sulfonyl)ethyl)acrylamide) (PFSNM), BAPS, together with oxygen, can be effectively delivered into hypoxic tumor cells through circulation and significantly inhibit the tumor growth. Therefore, BAPS-loaded PFSNM is an oxidative regulation nanosystem with remarkable therapeutic efficacy for chemodynamic therapy.


Asunto(s)
Disulfuros , Neoplasias , Humanos , Nanogeles , Glutatión/metabolismo , Estrés Oxidativo , Neoplasias/tratamiento farmacológico , Línea Celular Tumoral
19.
Front Microbiol ; 13: 920109, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35966692

RESUMEN

Phyllospheric microbial composition of tobacco (Nicotiana tabacum L.) is contingent upon certain factors, such as the growth stage of the plant, leaf position, and cultivar and its geographical location, which influence, either directly or indirectly, the growth, overall health, and production of the tobacco plant. To better understand the spatiotemporal variation of the community and the divergence of phyllospheric microflora, procured from healthy and diseased tobacco leaves infected by Alternaria alternata, the current study employed microbe culturing, high-throughput technique, and BIOLOG ECO. Microbe culturing resulted in the isolation of 153 culturable fungal isolates belonging to 33 genera and 99 bacterial isolates belonging to 15 genera. High-throughput sequencing revealed that the phyllosphere of tobacco was dominantly colonized by Ascomycota and Proteobacteria, whereas, the most abundant fungal and bacterial genera were Alternaria and Pseudomonas. The relative abundance of Alternaria increased in the upper and middle healthy groups from the first collection time to the third, whereas, the relative abundance of Pseudomonas, Sphingomonas, and Methylobacterium from the same positions increased during gradual leaf aging. Non-metric multi-dimensional scaling (NMDs) showed clustering of fungal communities in healthy samples, while bacterial communities of all diseased and healthy groups were found scattered. FUNGuild analysis, from the first collection stage to the third one in both groups, indicated an increase in the relative abundance of Pathotroph-Saprotroph, Pathotroph-Saprotroph-Symbiotroph, and Pathotroph-Symbiotroph. Inclusive of all samples, as per the PICRUSt analysis, the predominant pathway was metabolism function accounting for 50.03%. The average values of omnilog units (OUs) showed relatively higher utilization rates of carbon sources by the microbial flora of healthy leaves. According to the analysis of genus abundances, leaf growth and leaf position were the important drivers of change in structuring the microbial communities. The current findings revealed the complex ecological dynamics that occur in the phyllospheric microbial communities over the course of a spatiotemporal varying environment with the development of tobacco brown spots, highlighting the importance of community succession.

20.
Front Microbiol ; 13: 843389, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35572673

RESUMEN

In the tobacco phyllosphere, some of the microbes may have detrimental effects on plant health, while many may be neutral or even beneficial. Some cannot be cultivated, so culture-independent methods are needed to explore microbial diversity. In this study, both metagenetic analysis and traditional culture-dependent methods were used on asymptomatic healthy leaves and symptomatic diseased leaves of tobacco plants. In the culture-independent analysis, asymptomatic leaves had higher microbial diversity and richness than symptomatic leaves. Both asymptomatic and symptomatic leaves contained several potentially pathogenic bacterial and fungal genera. The putative bacterial pathogens, such as species of Pseudomonas, Pantoea, or Ralstonia, and putative fungal pathogens, such as species of Phoma, Cladosporium, Alternaria, Fusarium, Corynespora, and Epicoccum, had a higher relative abundance in symptomatic leaves than asymptomatic leaves. FUNGuild analysis indicated that the foliar fungal community also included endophytes, saprotrophs, epiphytes, parasites, and endosymbionts. PICRUSt analysis showed that the dominant functions of the bacterial community in a symptomatic leaf were cellular processes and environmental information processing. In the other five foliar samples, the dominant functions of the bacterial community were genetic information processing, metabolism, and organismal systems. In the traditional culture-dependent method, 47 fungal strains were isolated from 60 symptomatic tobacco leaf fragments bearing leaf spots. Among them, 21 strains of Colletotrichum (29%), Xylariaceae (14%), Corynespora (14%), Pestalotiopsis (10%), Alternaria (10%), Epicoccum (10%), Byssosphaeria (5%), Phoma (5%), and Diaporthe (5%) all fulfilled Koch's postulates and were found to cause disease on detached tobacco leaves in artificial inoculation tests. Symptoms on detached leaves caused by three strains of Corynespora cassiicola in artificial inoculation tests were similar to the original disease symptoms in the tobacco field. This study showed that the combined application of culture-dependent and independent methods could give comprehensive insights into microbial composition that each method alone did not reveal.

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