Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 134
Filtrar
Más filtros

Base de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
PhytoKeys ; 246: 251-263, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39301118

RESUMEN

Xantolisweimingii sp. nov. (Sapotaceae) is described and illustrated from Yunnan, southwest China. The new species is morphologically most similar to X.tomentosa (Roxb.) Raf., but differs from the latter in the ovate or obovate leaves, entirely glabrous corollas, lanceolate, ca. 5 mm long staminodes, fringed at the base. We provided a distribution map and a preliminary conservation assessment for the new species. Additionally, an updated dichotomous key to all known species of Xantolis is presented.

2.
Carbohydr Polym ; 345: 122577, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39227109

RESUMEN

This study was to investigate the antibacterial effects and metabolites derived from bifidobacterial fermentation of an exopolysaccharide EPS-LM produced by a medicinal fungus Cordyceps sinensis, Cs-HK1. EPS-LM was a partially purified polysaccharide fraction which was mainly composed of Man, Glc and Gal at 7.31:12.95:1.00 mol ratio with a maximum molecular weight of 360 kDa. After fermentation of EPS-LM in two bifidobacterial cultures, B. breve and B. longum, the culture digesta showed significant antibacterial activities, inhibiting the proliferation and biofilm formation of Escherichia coli. Based on untargeted metabolomic profiling of the digesta, the levels of short chain fatty acids, carboxylic acids, benzenoids and their derivatives were all increased significantly (p < 0.01), which probably contributed to the enhanced antibacterial activity by EPS-LM. Since EPS-LM was only slightly consumed for the bifidobacterial growth, it mainly stimulated the biosynthesis of bioactive metabolites in the bifidobacterial cells. The results also suggested that EPS-LM polysaccharide may have a regulatory function on the bifidobacterial metabolism leading to production of antibacterial metabolites, which may be of significance for further exploration.


Asunto(s)
Antibacterianos , Cordyceps , Escherichia coli , Fermentación , Polisacáridos Bacterianos , Antibacterianos/farmacología , Antibacterianos/química , Cordyceps/metabolismo , Cordyceps/química , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Polisacáridos Bacterianos/farmacología , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/metabolismo , Biopelículas/efectos de los fármacos , Polisacáridos Fúngicos/farmacología , Polisacáridos Fúngicos/química , Pruebas de Sensibilidad Microbiana
3.
Carbohydr Polym ; 343: 122478, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39174101

RESUMEN

Lentinula edodes (Shiitake) is an important edible mushroom and polysaccharides are its major constituents with proven health benefits. The study was to investigate the gut bacterial fermentation and subsequent effects on gut barrier function of a glucan-rich polysaccharide, LePS40 precipitated from the mushroom water extract with 40 % (v/v) ethanol. LePS40 consisted of a ß-(1→3)-glucan main chain with substitution in the C-6 position with side chains mainly composed of (1 → 6)-linked ß-Glcp residues, (1 → 6)-linked α-Galp residues and terminal residues of ß-Glcp. LePS40 was found highly resistant to digestive enzymes and gastric acid in simulated human gastrointestinal tract, but highly fermentable during in vitro human fecal fermentation. The fecal fermentation degradation of LePS40 appeared to selectively break the glucoside linkage in view of the dramatic decrease in the glucose molar ratio (12.68 to 1.07). Compared with the prebiotic reference FOS, LePS40 led to much higher levels of butyric, and propionic acid and a lower level of acetic acid. Moreover, LePS40 enhanced the abundance of some beneficial bacterial populations, but decreased the bacteria possibly linked with fatty-liver disease and colorectal cancer. Furthermore, the fecal fermentation products of LePS40 showed a potential protective effect on intestinal barrier function against inflammatory damage in Caco-2/Raw264.7 co-culture model. These findings suggest the potential of LePS40 for improvement of gut health through modulation of gut microbiota.


Asunto(s)
Fermentación , Microbioma Gastrointestinal , Hongos Shiitake , Hongos Shiitake/química , Hongos Shiitake/metabolismo , Humanos , Microbioma Gastrointestinal/efectos de los fármacos , Células CACO-2 , Animales , Heces/microbiología , Polisacáridos/farmacología , Polisacáridos/química , Polisacáridos/metabolismo , Digestión/efectos de los fármacos , Peso Molecular , Ratones , Mucosa Intestinal/metabolismo , Prebióticos
4.
Int J Biol Macromol ; 278(Pt 1): 134611, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39127278

RESUMEN

Deep eutectic solvent (DES) has been recognized as a promising plasticizer for the preparation of biodegradable food packaging films. In addition, DES-plasticized chitosan (CS) films could also serve as a favorable carrier for loading active components. In this work, a ternary composite film was fabricated by plasticizing chitosan with DES and the active ingredient proanthocyanidin (PA) was used as a cross-linking agent. The incorporation of PAs significantly enhanced the toughness, elasticity, and hydrophobicity of the ternary CS-DES-PA composite films. It achieved antioxidant and bacteriostatic functions. In particular, the ternary CS-DES-PA composite films had a thickness of 0.16 ± 0.01 µm, a tensile strength of 2.63 ± 0.48 MPa, and an elongation about 73.22 %. They also have improved water resistance, UV blocking, with a high-water contact angle of 88.4° and a low water swelling of 5 % on the surface of the film. Meanwhile, the PAs in the film could slow down the browning of litchi fruits. This ternary blended film (CS-DES-PA) achieves better compatibility of the active ingredient in the film-forming substrate. It also provides a green and biodegradable packaging material for food packaging.


Asunto(s)
Quitosano , Embalaje de Alimentos , Proantocianidinas , Quitosano/química , Proantocianidinas/química , Embalaje de Alimentos/métodos , Disolventes Eutécticos Profundos/química , Antioxidantes/química , Antioxidantes/farmacología , Fenómenos Químicos , Interacciones Hidrofóbicas e Hidrofílicas , Resistencia a la Tracción , Antibacterianos/química , Antibacterianos/farmacología , Agua/química
5.
Mol Phylogenet Evol ; 196: 108084, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38688440

RESUMEN

The tribe Collabieae (Epidendroideae, Orchidaceae) comprises approximately 500 species. Generic delimitation within Collabieae are confusing and phylogenetic interrelationships within the Collabieae have not been well resolved. Plastid genomes and nuclear internal transcribed spacer (ITS) sequences were used to estimate the phylogenetic relationships, ancestral ranges, and diversification rates of Collabieae. The results showed that Collabieae was subdivided into nine clades with high support. We proposed to combine Ancistrochilus and Pachystoma into Spathoglottis, merge Collabium and Chrysoglossum into Diglyphosa, and separate Pilophyllum and Hancockia as distinctive genera. The diversification of the nine clades of Collabieae might be associated with the uplift of the Himalayas during the Late Oligocene/Early Miocene. The enhanced East Asian summer monsoon in the Late Miocene may have promoted the rapid diversification of Collabieae at a sustained high diversification rate. The increased size of terrestrial pseudobulbs may be one of the drivers of Collabieae diversification. Our results suggest that the establishment and development of evergreen broadleaved forests facilitated the diversification of Collabieae.


Asunto(s)
Orchidaceae , Filogenia , Orchidaceae/genética , Orchidaceae/clasificación , Bosques , Genoma de Plastidios/genética , Filogeografía , ADN Espaciador Ribosómico/genética , Análisis de Secuencia de ADN , Asia , ADN de Plantas/genética
6.
Pathogens ; 13(1)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38251358

RESUMEN

Pathogen discovery plays a crucial role in the fields of infectious diseases, clinical microbiology, and public health. During the past four years, the global response to the COVID-19 pandemic highlighted the importance of early and accurate identification of novel pathogens for effective management and prevention of outbreaks. The post-COVID era has ushered in a new phase of infectious disease research, marked by accelerated advancements in pathogen discovery. This review encapsulates the recent innovations and paradigm shifts that have reshaped the landscape of pathogen discovery in response to the COVID-19 pandemic. Primarily, we summarize the latest technology innovations, applications, and causation proving strategies that enable rapid and accurate pathogen discovery for both acute and historical infections. We also explored the significance and the latest trends and approaches being employed for effective implementation of pathogen discovery from various clinical and environmental samples. Furthermore, we emphasize the collaborative nature of the pandemic response, which has led to the establishment of global networks for pathogen discovery.

7.
World J Clin Cases ; 11(35): 8357-8363, 2023 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-38130621

RESUMEN

BACKGROUND: Ischemic gastritis is a clinically rare disease with high mortality that infrequently reported in the medical literature and under-recognized clinically and histopathologically. Early diagnosis and treatment can only be achieved through upper gastrointestinal endoscopy after symptoms appear. CASE SUMMARY: A 68-year-old woman with a history of intracranial aneurysm developed dizziness, chest tightness and unconsciousness for 2 d. Computed tomography angiography showed diffuse coronary atherosclerosis, moderate to severe stenosis in the proximal end of the left anterior descending branch, multiple calcified plaques in the proximal end of the circumflex branch and right coronary artery, and mild to moderate stenosis. The patient also developed diffuse atherosclerosis in the splenic and mesenteric arteries, with mild lumen stenosis and atherosclerosis in the abdominal aorta and its branches. Endoscopy showed submucosal congestion and damage of the entire gastric mucosa, of which the fundus and body of the stomach were most seriously affected. The mucosa was swollen, with a deep purple color, surface erosion and dark red oozing blood. Pathological examination showed bleeding and necrosis of the gastric mucosa, with residual contours of the gastric glands, consistent with ischemic gastritis. CONCLUSION: Ischemic gastritis is a rare disease that may be difficult to diagnose as its symptoms may be similar to those of other gastrointestinal diseases. Diagnosis is usually based on endoscopic and pathological examinations, which show insufficient blood supply to the gastric mucosa leading to mucosal damage and necrosis.

8.
Virus Genes ; 59(5): 786-789, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37530925

RESUMEN

Northern pintail (Anas acuta) is a migratory waterfowl that can transmit various viruses. The genome sequence of a Sobemovirus was determined using metagenomic sequencing from the feces of northern pintail (Anas acuta) in Xinjiang, northwest China. The virus possesses a linear RNA molecule of 4177 bp and is most closely related to isolates SoMV-WA (GenBank accession no. HM163159.1) and ATCC PV-109 (GenBank accession no. GQ845002.2), with a nucleotide identity of 86.7%. The virus encodes four open reading frames (ORF) coding for four proteins, and phylogenetic analysis of capsid protein and RNA-dependent RNA polymerase (RdRp) showed that the strain was clustered into the species Sowbane Mosaic Virus (SoMV). The amino acid sequence identity of capsid protein was 89.6-90.9% to other isolates of SoMV, but 17.6-31.4% similar to other strains in the genus Sobemovirus, indicating a strain of Sowbane Mosaic Virus. This is the first report of SoMV in the feces of wild birds and in China, and it suggested that northern pintail likely plays an alternative role in the transmission of SoMV.


Asunto(s)
Proteínas de la Cápside , Virus ARN , Animales , Proteínas de la Cápside/genética , Filogenia , Patos , Virus ARN/genética , Heces , Genoma Viral/genética , Sistemas de Lectura Abierta
9.
PLoS One ; 18(6): e0286865, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37289817

RESUMEN

OBJECTIVE: To examine multiple genotypes of Ophiocordyceps sinensis in a semi-quantitative manner in the stromal fertile portion (SFP) densely covered with numerous ascocarps and ascospores of natural Cordyceps sinensis and to outline the dynamic alterations of the coexisting O. sinensis genotypes in different developmental phases. METHODS: Mature Cordyceps sinensis specimens were harvested and continuously cultivated in our laboratory (altitude 2,254 m). The SFPs (with ascocarps) and fully and semi-ejected ascospores were collected for histological and molecular examinations. Biochip-based single nucleotide polymorphism (SNP) MALDI-TOF mass spectrometry (MS) was used to genotype multiple O. sinensis mutants in the SFPs and ascospores. RESULTS: Microscopic analysis revealed distinct morphologies of the SFPs (with ascocarps) before and after ascospore ejection and SFP of developmental failure, which, along with the fully and semi-ejected ascospores, were subjected to SNP MS genotyping analysis. Mass spectra showed the coexistence of GC- and AT-biased genotypes of O. sinensis that were genetically and phylogenetically distinct in the SFPs before and after ejection and of developmental failure and in fully and semi-ejected ascospores. The intensity ratios of MS peaks were dynamically altered in the SFPs and the fully and semi-ejected ascospores. Mass spectra also showed transversion mutation alleles of unknown upstream and downstream sequences with altered intensities in the SFPs and ascospores. Genotype #5 of AT-biased Cluster-A maintained a high intensity in all SFPs and ascospores. An MS peak with a high intensity containing AT-biased Genotypes #6 and #15 in pre-ejection SFPs was significantly attenuated after ascospore ejection. The abundance of Genotypes #5‒6 and #16 of AT-biased Cluster-A was differentially altered in the fully and semi-ejected ascospores that were collected from the same Cordyceps sinensis specimens. CONCLUSION: Multiple O. sinensis genotypes coexisted in different combinations with altered abundances in the SFPs prior to and after ejection, the SFP of developmental failure, and the two types of ascospores of Cordyceps sinensis, demonstrating their genomic independence. Metagenomic fungal members present in different combinations and with dynamic alterations play symbiotic roles in different compartments of natural Cordyceps sinensis.


Asunto(s)
Cordyceps , Cordyceps/genética , Polimorfismo de Nucleótido Simple , Espectrometría de Masas , Esporas Fúngicas/genética , Genotipo
10.
J Hazard Mater ; 445: 130570, 2023 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-37055976

RESUMEN

This study investigated the behavior of veterinary antibiotics (VAs) in a small farm ecosystem. Manure and environmental samples were collected around a large pig farm in northeast China. Thirty-four VAs in six categories were analyzed. Then, a multimedia fugacity model was used to estimate the fates of VAs in the environment. The results showed that VAs were prevalent in manure, soil, water, and sediment, but not in crops. Compared with fresh manure, VA levels were significantly lower in surface manure piles left in the open air for 3-6 months. The main VAs, tetracyclines and quinolones, decreased by 427.12 and 158.45 µg/kg, respectively. VAs from manure piles were transported to the surroundings and migrated vertically into deep soil. The concentrations of ∑VAs detected in agricultural soils were 0.03-4.60 µg/kg; > 94% of the mass inventory of the VAs was retained in soil organic matter (SOM), suggesting that SOM is the main reservoir for antibiotics in soil. Risk assessment and model analysis indicated that the negative impact of mixed antibiotics at low concentrations in farmland on crops may be mediated by indirect effects, rather than direct effects. Our findings highlight the environmental fates and risks of antibiotics from livestock farms.


Asunto(s)
Antibacterianos , Monitoreo del Ambiente , Contaminantes del Suelo , Drogas Veterinarias , Animales , Antibacterianos/análisis , China , Productos Agrícolas , Ecosistema , Monitoreo del Ambiente/métodos , Granjas , Estiércol/análisis , Suelo , Contaminantes del Suelo/análisis , Porcinos , Drogas Veterinarias/análisis
11.
Ying Yong Sheng Tai Xue Bao ; 34(3): 835-845, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37087668

RESUMEN

With the continuous decline of global biodiversity, biodiversity conservation has attracted more and more attention from the international society. In order to slow down the trend of biodiversity decline, it is particularly important to identify key areas for biodiversity conservation. However, most of current methods for identifying important areas have different assessment criteria and focus on different biological assemblages (species or communities) and ecosystem types. Key biodiversity areas (KBAs) are sites that contribute significantly to global biodiversity persistence. Unlike traditional research and identification methods, KBAs identification is based on a unified global standard to explore habitats that are critical to endangered plants and animals in terrestrial, freshwater, and marine ecosystems. Based on the theoretical and technical framework of KBAs, we summarized the system of identification criteria and assessment parameters for KBAs. The five high-level criteria are separated into eleven sub-level criteria. Among the eleven evaluation parameters, there is one evaluation parameter for the ecosystem level, eight evaluation parameters for the species level, one evaluation parameter for the gene level, and one comprehensive evaluation parameter. In addition, we analyzed the application of KBAs identification in biodiversity research and conservation combined with relevant domestic and foreign research cases. Furthermore, we discussed the future development direction and application prospect of KBAs identification method in China. This method could provide a new perspective for the formulation of ecological protection policies and the planning of naturally protected areas in China.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Animales , Conservación de los Recursos Naturales/métodos , Biodiversidad , Agua Dulce , China
12.
Int J Biol Macromol ; 237: 124216, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36990414

RESUMEN

A hyphenated process, autoclaving followed by ultrasonication (AU), was evaluated for efficient extraction of polysaccharides (PS) from Lentinula edodes (Shiitake) mushroom. The PS yield (w/w) was 8.44 % from hot-water extraction (HWE), 11.01 % by autoclaving extraction (AE), and 16.3 % by AUE. The AUE water extract was subject to fractional precipitation in four-steps with increasing ethanol concentration of 40 %, 50 %, 70 % and 80 % (v/v), yielding four PS fractions in descending molecular weight (MW), PS40 > PS50 > PS70 > PS80. All the four PS fractions were composed of four monosaccharide residues, mannose (Man), glucose (Glc) and galactose (Gal) but in different mole ratios. The PS40 fraction with the highest average MW (4.98 × 106) was the most abundant fraction, accounting for 64.4 % of the total PS mass and also had the highest glucose molar ratio (~80 %). PS40 also most significantly enhanced the NO, and ROS generation and phagocytic activity in RAW 264.7 cells. The results proved that AUE followed by fractional ethanol precipitation is an efficient strategy with reduced solvent expenditure for isolation of the major immunostimulatory PS from L. edodes mushroom.


Asunto(s)
Hongos Shiitake , Humanos , Hongos Shiitake/química , Precipitación Fraccionada , Polisacáridos/química , Agua , Glucosa , Etanol
13.
PLoS One ; 18(3): e0270776, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36893131

RESUMEN

OBJECTIVE: To examine the differential occurrence of Ophiocordyceps sinensis genotypes in the stroma, stromal fertile portion (SFP) densely covered with numerous ascocarps, and ascospores of natural Cordyceps sinensis. METHODS: Immature and mature C. sinensis specimens were harvested. Mature C. sinensis specimens were continuously cultivated in our laboratory (altitude 2,200 m). The SFPs (with ascocarps) and ascospores of C. sinensis were collected for microscopic and molecular analyses using species-/genotype-specific primers. Sequences of mutant genotypes of O. sinensis were aligned with that of Genotype #1 Hirsutella sinensis and compared phylogenetically using a Bayesian majority-rule method. RESULTS: Fully and semiejected ascospores were collected from the same specimens. The semiejected ascospores tightly adhered to the surface of the asci as observed by the naked eye and under optical and confocal microscopies. The multicellular heterokaryotic ascospores showed uneven staining of nuclei. The immature and mature stromata, SFPs (with ascocarps) and ascospores were found to differentially contain several GC- and AT-biased genotypes of O. sinensis, Samsoniella hepiali, and an AB067719-type fungus. The genotypes within AT-biased Cluster-A in the Bayesian tree occurred in all compartments of C. sinensis, but those within AT-biased Cluster-B were present in immature and mature stromata and SPFs but absent in the ascospores. Genotype #13 of O. sinensis was present in semi-ejected ascospores and Genotype #14 in fully ejected ascospores. GC-biased Genotypes #13-14 featured large DNA segment substitutions and genetic material recombination between the genomes of the parental fungi (H. sinensis and the AB067719-type fungus). These ascosporic offspring genotypes combined with varying abundances of S. hepiali in the 2 types of ascospores participated in the control of the development, maturation and ejection of the ascospores. CONCLUSION: Multiple genotypes of O. sinensis coexist differentially in the stromata, SFPs and 2 types of C. sinensis ascospores, along with S. hepiali and the AB067719-type fungus. The fungal components in different combinations and their dynamic alterations in the compartments of C. sinensis during maturation play symbiotic roles in the lifecycle of natural C. sinensis.


Asunto(s)
Cordyceps , Cordyceps/genética , Teorema de Bayes , ADN , Cartilla de ADN/genética , Genotipo
14.
Int J Biol Macromol ; 226: 423-433, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36473526

RESUMEN

Hypocrellins are fungal perylenequinones (PQs) from Shiraia fruiting bodies and potential photosensitizers for cancer photodynamic therapy. Shiraia fruiting bodies harbor diverse bacterial communities dominated by Pseudomonas. The present study was to characterize the exopolysaccharide (EPS) of P. fulva SB1 which acted as an elicitor to stimulate the PQ accumulation of the host Shiraia. A bacterial EPS named EPS-1 was purified from the culture broth of P. fulva SB1, which consisted of mannose (Man) and glucose (Glc) with an average molecular weight of 9.213 × 104 Da. EPS-1 had (1 â†’ 2)-linked α-mannopyranose (Manp) backbone and side chains of α-D-Manp-(1→ and α-D-Manp-(1 â†’ 6)-ß-D-Glcp-(1 â†’ 6)-α-D-Manp(1 â†’ group attached to the O-6 positions of (1 â†’ 2)-α-D-Manp. EPS-1 at 30 mg/L stimulated both intracellular and extracellular hypocrellin A (HA) by about 3-fold of the control group. The EPS-1 treatment up-regulated the expression of key genes for HA biosynthesis. The elicitation of HA biosynthesis by EPS-1 was strongly dependent on the induced reactive oxygen species (ROS) generation. The results may provide new insights on the role of bacterial EPS in bacterium-fungus interactions and effective elicitation strategy for hypocrellin production in mycelial cultures.


Asunto(s)
Ascomicetos , Perileno , Fotoquimioterapia , Humanos , Quinonas/farmacología , Quinonas/metabolismo , Fenol/metabolismo , Perileno/farmacología , Perileno/metabolismo , Ascomicetos/genética
15.
F1000Res ; 11: 180, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36111216

RESUMEN

BACKGROUND: As Malaysia struggles with the battle to retain talented workers, the retention of persons with disabilities (PWDs) remains a major challenge in innovation management. Malaysia currently has the lowest retention of PWDs in innovation management in The Association of Southeast Asian Nations (ASEAN). The purpose of this study is to develop a unique framework to enhance the inclusion of PWDs in Malaysia.  Methods: A questionnaire was distributed to 200 PWDs in the central region of Malaysia.   Results: Based on the results of this research, four crucial variables (salary, compensation, career advancement and reward management) contributed to the lack of involvement in innovation management among PWDs in Malaysia.  Conclusions: This study only focuses on 200 PWDs in Malaysia. Despite the fact that PWDs' involvement in innovation management is the lowest, there is a lack of research initiative and practitioner commitment to address this issue. Serving as preliminary research in Malaysia, this study develops a unique framework to fill the gap.


Asunto(s)
Personas con Discapacidad , Humanos , Malasia , Encuestas y Cuestionarios
16.
Materials (Basel) ; 15(16)2022 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-36013754

RESUMEN

Natural polysaccharides are attractive and promising biomacromolecules for the green synthesis of silver nanoparticles (Ag NPs) with a broad spectrum of useful functions. This study aims to evaluate the synthetic conditions and physical properties of Ag NPs using three fractions of exopolysaccharide (EPS), namely EPS-1, EPS-2, and EPS-3, produced by a medicinal fungus known as Cs-HK1, with variations in their chemical composition and molecular weight. Each of the EPS fractions had a unique set of optimal synthetic conditions (reaction time course, temperature, and reagent concentration), resulting in a specific range of Ag NP size distributions. The Ag NPs synthesized with the EPS-1 fraction had the smallest particle size (~160 nm) and the most significant antibacterial activities against Escherichia coli (Gram-) and Staphylococcus aureus (Gram+), with a minimal inhibitory concentration (MIC) of 0.2 mg/mL on E. coli and 0.075 mg/mL on S. aureus. The results proved the success of the scheme of this green synthesis scheme with all three EPS fractions and the potential antibacterial application of EPS-coated Ag NPs.

17.
Front Vet Sci ; 9: 846634, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35812856

RESUMEN

Visna/Maedi virus (VMV) is a neglected pathogen that damages sheep and goats' nervous and respiratory systems. The virus was discovered 80 years ago and has been endemic in China for nearly four decades; nevertheless, there is little information regarding Chinese isolates' genotypes and genomic characteristics. In this study, the proviral DNA of strains isolated in 1985 and 1994 were extracted, and the proviral DNA was subjected to Illumina sequencing combined with Sanger sequencing of poor coverage regions. The results showed that the two isolates were clustered with genotype A2 and shared 78.3%-89.1% similarity to reference VMV genome sequences, with the highest similarity (88.7%-89.1%) to the USA strain USMARC-200212120-r (accession no. MT993908.1) and lowest similarity (78.3%-78.5%) to the Italian strain SRLV009 (accession no. MG554409.1). A maximum-likelihood tree showed that the Chinese VMV strains and the USA strain 1150 (accession no. MH916859.1) comprise a monophyletic group with a short tree branch. Our data filled the gap in genomic analysis and viral evolution in Chinese VMV strains, and would be benefit China's source-tracing and eradication program development in China.

18.
Sci Total Environ ; 834: 155361, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35460793

RESUMEN

Organophosphate esters (OPEs) in the environment have been the focus of increasing attention due to their ubiquity and potential toxicity. However, there is little information on the occurrence and characteristics of OPEs in rural areas, especially those with cold year-round temperatures and frozen soil in winter. In this study, environmental samples were collected, in summer and winter, from villages and towns in Northeast China differing in the types and intensities of their anthropogenic activities. The samples were analyzed for 12 OPEs. The results showed the widespread presence of alkyl-OPEs, Cl-OPEs, and aryl-OPEs in the water, soil, snow, and ice of the study sites. In summer, tris(1-chloro-2-propyl) phosphate (TCPP) and tris(2-chloroethyl) phosphate (TCEP) were the primary compounds in water and soil, respectively. The ∑12OPE concentration in three villages varied from 46.26 to 257.37 ng/L in water, and from 6.62 to 19.46 ng/g in soils. The ∑12OPE concentrations in water were lower in winter than summer, but conversely, ∑12OPE concentrations in frozen soils in winter were higher than those in soils in summer. In winter, there was a shift in the predominant OPEs in water and frozen soils, with dominance of TCEP and complex compounds, respectively. Obvious seasonal characteristics of the potential sources and ecological risks of OPEs in these areas were also determined, with more complex sources of OPEs seen in summer than winter. In summer, only 2-ethylhexyl diphenyl phosphate (EHDPP) in water posed a potential risk, while in summer and, especially, in winter, EHDPP and tris(2-ethylhexyl) phosphate posed potential risks in soils. The high ∑12OPE concentration in snow (56.77 ng/L) implied that wet deposition can amplify OPEs in other environmental compartments. This is the first systematic report on OPEs in a cold rural area. Our findings highlight the need for seasonal monitoring of OPEs in similar areas.


Asunto(s)
Retardadores de Llama , China , Monitoreo del Ambiente/métodos , Ésteres , Retardadores de Llama/análisis , Organofosfatos , Fosfatos , Estaciones del Año , Suelo , Agua
19.
One Health ; 14: 100376, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35252529

RESUMEN

Hepatitis E virus (HEV) causes infections in humans and animals. HEV have been identified in pig farms, markets and swine workers, but studies with parallel observations along the poultry and pork supply chains remains limited. This study aimed to characterize HEV infection risks in workers along the meat supply chain. Two rounds of cross-sectional surveys were performed among swine and poultry workers in pig and poultry farms, slaughterhouses, wholesale and retail live poultry markets, live pig markets and pork markets. Human sera from the workers and the general population were collected and tested for HEV specific IgM/IgG antibodies by commercial indirect-ELISA test kits. Risk factors of HEV seropositivity associated with different occupational settings were identified using logistic regression. 47.0% (156/332) of the swine workers and 40.2% (119/296) of the poultry workers were seropositive, compared to 26.1% (35/134) in the general population. Multivariable analysis showed that human HEV infection risk increased along the pork supply chain, with the highest risk at pig slaughterhouses (adjusted OR = 3.19, 95% CI = 1.49-6.88) and pork markets (adjusted OR = 2.02, 95% CI = 1.04-3.97), but no significant higher risk was observed among poultry workers. Swine occupational exposure is associated with HEV infection, especially in workers in pig slaughterhouses and pork markets. Strengthening control measures in these settings is important for HEV control and long term HEV elimination.

20.
PhytoKeys ; 206: 75-86, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36761271

RESUMEN

Breyniahiemalis Huan C. Wang & Feng Yang (Phyllanthaceae), of sect. Cryptogynium (Müll.Arg.) Welzen & Pruesapan in subg. Breynia, is described from Yunnan, south-west China. It is known from only a single locality in the valley of the Yuanjiang River, and usually occurs in the understory of the savanna vegetation. It is characterized by its broadly elliptic to orbicular leaf blades, shallowly plate-like calyces of the staminate flowers, ovaries with clearly erose rim and urceolate capsules. Morphological comparisons with similar species are also presented.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA