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Microbes strongly affect invasive plant growth. However, how phyllosphere and rhizosphere soil microbes distinctively affect seedling mortality and growth of invaders across ontogeny under varying soil nutrient levels remains unclear. In this study, we used the invader Ageratina adenophora to evaluate these effects. We found that higher proportions of potential pathogens were detected in core microbial taxa in leaf litter than rhizosphere soil and thus leaf inoculation had more adverse effects on seed germination and seedling survival than soil inoculation. Microbial inoculation at different growth stages altered the microbial community and functions of seedlings, and earlier inoculation had a more adverse effect on seedling survival and growth. The soil nutrient level did not affect microbe-mediated seedling growth and the relative abundance of the microbial community and functions involved in seedling growth. The effects of some microbial genera on seedling survival are distinct from those on growth. Moreover, the A. adenophora seedling-killing effects of fungal strains isolated from dead seedlings by non-sterile leaf inoculation exhibited significant phylogenetic signals, by which strains of Allophoma and Alternaria generally caused high seedling mortality. Our study stresses the essential role of A. adenophora litter microbes in population establishment by regulating seedling density and growth.
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Ageratina , Folhas de Planta , Rizosfera , Plântula , Microbiologia do Solo , Ageratina/microbiologia , Plântula/microbiologia , Plântula/crescimento & desenvolvimento , Folhas de Planta/microbiologia , Folhas de Planta/crescimento & desenvolvimento , Microbiota , Espécies Introduzidas , GerminaçãoRESUMO
Climate change, microbial endophytes, and local plants can affect the establishment and expansion of invasive species, yet no study has been performed to assess these interactions. Using a growth chamber, we integrated the belowground (rhizosphere soils) and aboveground (mixture of mature leaf and leaf litter) microbiota into an experimental framework to evaluate the impacts of four native plants acting as microbial inoculation sources on endophyte assembly and growth of the invasive plant Ageratina adenophora in response to drought stress and temperature change. We found that fungal and bacterial enrichment in the leaves and roots of A. adenophora exhibited distinct patterns in response to climatic factors. Many fungi were enriched in roots in response to high temperature and drought stress; in contrast, many bacteria were enriched in leaves in response to low temperature and drought stress. Inoculation of microbiota from phylogenetically close native plant species (i.e., Asteraceae Artemisia atrovirens) causes the recipient plant A. adenophora (Asteraceae) to enrich dominant microbial species from inoculation sources, which commonly results in a lower dissimilar endophytic microbiota and thus produces more negative growth effects when compared to non-Asteraceae inoculations. Drought, microbial inoculation source, and temperature directly impacted the growth of A. adenophora. Both drought and inoculation also indirectly impacted the growth of A. adenophora by changing the root endophytic fungal assembly. Our data indicate that native plant identity can greatly impact the endophyte assembly and host growth of invasive plants, which is regulated by drought and temperature.IMPORTANCEThere has been increasing interest in the interactions between global changes and plant invasions; however, it remains to quantify the role of microbial endophytes in plant invasion with a consideration of their variation in the root vs leaf of hosts, as well as the linkages between microbial inoculations, such as native plant species, and climatic factors, such as temperature and drought. Our study found that local plants acting as microbial inoculants can impact fungal and bacterial enrichment in the leaves and roots of the invasive plant Ageratina adenophora and thus produce distinct growth effects in response to climatic factors; endophyte-mediated invasion of A. adenophora is expected to operate more effectively under favorable moisture. Our study is important for understanding the interactions between climate change, microbial endophytes, and local plant identity in the establishment and expansion of invasive species.
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Ageratina , Asteraceae , Endófitos/fisiologia , Plantas/microbiologia , Ageratina/fisiologia , Espécies Introduzidas , Bactérias , Raízes de Plantas/microbiologia , Microbiologia do SoloRESUMO
To understand the disease-mediated invasion of exotic plants and the potential risk of disease transmission in local ecosystems, it is necessary to characterize population genetic structure and spatio-temporal dynamics of fungal community associated with both invasive and co-occurring plants. In this study, multiple genes were used to characterize the genetic diversity of 165 strains of Colletotrichum gloeosporioides species complex (CGSC) isolated from healthy leaves and symptomatic leaves of invasive plant Ageratina adenophora, as well as symptomatic leaves of its neighbor plants from eleven geographic sites in China. The data showed that these CGSC strains had a high genetic diversity in each geographic site (all Hd > 0.67 and Pi > 0.01). Haplotype diversity and nucleotide diversity varied greatly in individual gene locus: gs had the highest haplotype diversity (Hd = 0.8972), gapdh had the highest nucleotide diversity (Pi = 0.0705), and ITS had the lowest nucleotide diversity (Pi = 0.0074). Haplotypes were not clustered by geographic site, invasive age, or isolation source. AMOVA revealed that the genetic variation was mainly from within-populations, regardless of geographic or isolation origin. Both AMOVA and neutrality tests indicated these CGSC strains occurred gene exchange among geographic populations but did not experience population expansion along with A. adenophora invasion progress. Our data indicated that A. adenophora primarily accumulated these CGSC fungi in the introduced range, suggesting a high frequency of CGSC transmission between A. adenophora and co-occurring neighbor plants. This study is valuable for understanding the disease-mediated plant invasion and the potential risk of disease transmission driven by exotic plants in local ecosystems.
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Ageratina , Colletotrichum , Ageratina/genética , Ageratina/microbiologia , Espécies Introduzidas , Ecossistema , Colletotrichum/genéticaRESUMO
During an investigation of the fungal pathogens associated with the invasive weed Ageratina adenophora from China, some interesting isolates were obtained from healthy leaf, leaf spot, and roots of this weed. Among them, a novel genus Mesophoma, containing two novel species M. speciosa and M. ageratinae, was found. Phylogenetic analysis of the combined, the internal transcribed spacer (ITS), large nuclear subunit ribosomal DNA (LSU), the RNA polymerase II second largest subunit (rpb2), and the partial ß-tubulin (tub2) sequences, showed that M. speciosa and M. ageratinae formed a distinct clade far from all genera previously described in the family Didymellaceae. Combined distinctive morphological characters, including smaller and aseptate conidia when comparing with nearby genera Stagonosporopsis, Boeremia, and Heterphoma, allowed us to describe them as novel species belonging to a novel genus Mesophoma. The full descriptions, illustrations, and a phylogenetic tree showing the position of both M. speciosa and M. ageratinae are provided in this paper. Moreover, the potential for two strains belonging to these two species to be developed into a biocontrol for the spread of the invasive weed Ag. adenophora is also discussed.
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Ascomicetos , Filogenia , DNA Fúngico/genética , DNA Ribossômico/genética , Ascomicetos/genética , ChinaRESUMO
Many wild ornamental plant species have been introduced to improve the landscape of cities; however, until now, no study has been performed to explore the composition and function of foliar endophytes associated with cultivated rare plants in cities after their introduction. In this study, we collected the leaves of the healthy ornamental plant Lirianthe delavayi from wild and artificially cultivated habitats in Yunnan and compared their diversity, species composition, and functional predictions of their foliar endophytic fungal community based on high-throughput sequencing technology. In total, 3125 ASVs of fungi were obtained. The alpha diversity indices of wild L. delavayi populations are similar to those of cultivated samples; however, the species compositions of endophytic fungal ASVs were significantly varied in the two habitats. The dominant phylum is Ascomycota, accounting for more than 90% of foliar endophytes in both populations; relatively, artificial cultivation trends to increase the frequency of common phytopathogens of L. delavayi, such as Alternaria, Erysiphe. The relative abundance of 55 functional predictions is different between wild and cultivated L. delavayi leaves (p < 0.05); in particular, chromosome, purine metabolism, and peptidases are significantly increased in wild samples, while flagellar assembly, bacterial chemotaxis, and fatty acid metabolism are significantly enhanced in cultivated samples. Our results indicated that artificial cultivation can greatly change the foliar endophytic fungal community of L. delavayi, which is valuable for understanding the influence of the domestication process on the foliar fungal community associated with rare ornamental plants in urban environments.
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Cordyceps cicadae is an entomogenous fungus with important uses in traditional Chinese medicine. However, its wild resources have not met consumers' demand due to excessive harvesting practices. Artificial cultivation is therefore an important alternative, but research on cultivating C. cicadae in natural habitats has not been reported. In this study, we aimed to explore the viability of cultivating C. cicadae in a natural habitat, in the soil of Pinus massoniana forest. We assessed and compared the yield, metabolite contents and bacterial community composition of C. cicadae grown in the Antheraea pernyi pupae at different growth stages, and under different cultivation conditions, in the soil of a natural habitat and in sterile glass bottles. Our results showed that cultivating C. cicadae in a natural habitat is feasible, with up to 95% of pupae producing C. cicadae fruiting bodies. The content of nitrogen compounds (amino acids) in C. cicadae cultivated in a natural habitat was significantly higher than in glass bottles, while the yield and carbon compound (mannitol and polysaccharide) and nucleoside (cordycepin and adenosine) contents were lower. Different bacterial genera were enriched in C. cicadae at different growth stages and cultivation environments, and these bacterial genera were closely related to metabolites contents during growth. This study demonstrated the viability of a novel cultivation method of C. cicadae, which could be used as an alternative to wild stocks of this fungus. These findings provided new insights into the growth mechanism of C. cicadae and its interaction with soil microorganisms.
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INTRODUCTION: Bacterial vaginosis (BV) is a highly prevalent vaginal polymicrobial disorder commonly encountered in women of childbearing age. Therapy with only recommended antibiotics results in low cure rates and unacceptably high recurrence rates. The use of probiotics as a complementary approach for use with antibiotics for the treatment of BV remains unclear. This review aims to assess the efficacy of lactobacilli administered intravaginally in conjunction with antibiotics for the treatment of BV. METHODS AND ANALYSIS: The Cochrane Central Register of Controlled Trials in The Cochrane Library, Cochrane Library of Systematic Reviews, Medline/PubMed and Embase will be used to search for articles from database inception to November 2016. Randomised controlled clinical trials using lactobacilli administered intravaginally in conjunction with antibiotics to treat BV will be included. Primary outcome will be the BV cure rate. The recurrence rate will be examined as secondary outcome. Two reviewers will independently select trials and extract data from the original publications. The risk of bias will be assessed according to the Cochrane Risk of Bias tool. We will perform data synthesis using the Review Manager (RevMan) software V.5.2.3. To assess heterogeneity, we will compute the I2 statistic. ETHICS AND DISSEMINATION: This study will be a review of published data and it is not necessary to obtain ethical approval. Findings of this systematic review will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: International Prospective Register of Systematic Reviews 2014: CRD42014015079.
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Antibacterianos/uso terapêutico , Probióticos/administração & dosagem , Projetos de Pesquisa , Vaginose Bacteriana/terapia , Administração Intravaginal , Terapia Combinada , Feminino , Humanos , Lactobacillus , Revisões Sistemáticas como AssuntoRESUMO
The study was conducted to investigate the changes of intestinal microbiota composition and innate immunity with different dietary dosages of aspartate (Asp) supplementation. Thirty-six female ICR mice were divided randomly to four groups and thereafter fed the basal diets (controls) or those supplemented with additional 0.5, 1.0 and 2.0% aspartate. After 2 week feeding, microbial composition in ileum and feces, gene expression of pro-inflammatory cytokine, and innate immune factors in ileum were determined. The ratio of Firmicutes: Bacteroidetes in ileum and feces decreased in 0.5 and 1.0% Asp-supplemented groups, whereas this ratio increased in feces in 2.0% Asp-supplemented group. Meanwhile, the gene expression of IL-17 and IFN-γ in ileum decreased in 1.0% Asp-supplemented group; the gene expression in ileum of Muc2 decreased in 0.5 and 1.0% Asp-supplemented groups. Dietary supplementation with 2.0% Asp enhanced the expression of pIgR and Crp1 as compared to the other three groups. The results indicated that dietary 1.0% Asp supplementation lowers the ratio of Firmicutes:Bacteroidetes, which affects the innate immunity by decreasing the gene expression of IL-17, IFN-γ, and Muc2 in ileum.
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Ácido Aspártico/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Íleo/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Animais , Ácido Aspártico/administração & dosagem , Suplementos Nutricionais , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Íleo/imunologia , Íleo/microbiologia , Interferon gama/genética , Interleucina-17/genética , Camundongos , Camundongos Endogâmicos ICR , Mucina-2/genética , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genéticaRESUMO
Patients suffering from cardiovascular diseases (CVDs) experience a low quality of life and increase pressure on healthcare systems both nationally and globally. DNA methylation, which refers to the pathway by which DNA methyltransferase facilitates the addition of a methyl group to DNA, is of critical importance in this respect primarily because the epigenetic modification is implicated in a range of serious conditions including atherosclerosis, CVDs, and cancer. Research findings indicate that the number of epigenetic alterations can be elicited (both in utero and in adults) through the administration of certain nutritional supplements, including folic acid and methionine; this is partly attributable to the effect employed by methyl-containing nutrients in DNA methylation. Thus, for the purpose of illuminating viable therapeutic measures and preventive strategies for CVDs, research should continue to explore the intricate associations that exist between epigenetic regulation and CVD pathogenesis. This review centers on an exposition of the mechanism by which DNA methylation takes place, the impact it has on a range of conditions, and the potential clinical value of nutrition, driven mainly by the observation that nutritional supplements such as folic acid can affect DNA methylation.
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Doenças Cardiovasculares/genética , Doenças Cardiovasculares/patologia , Metilação de DNA , Suplementos Nutricionais , Ácido Fólico/farmacologia , Animais , Epigênese Genética , Humanos , Estado NutricionalRESUMO
Human papillomavirus (HPV) is associated with several disorders of the genital tract, skin, and oropharynx. This study investigated the prevalence of infection by 37 HPV genotypes among women of the Beijing area in China. Cervical specimens from 1,082 patients and 165 healthy controls were tested for HPV genotypes using a chip hybridization assay. Based on the local pathology, patients were divided into cervicitis and cervical lesion groups. Overall HPV infection rates were 30.5% for the cervicitis group and 78.4% for the cervical lesion group; whereas infection rates for high-risk HPV types (i.e., those associated with cervical cancers) were 24.0% and 73.4%, respectively. The most common HPV genotypes were HPV 52, 16, 81, 58, and 18 in healthy controls, HPV 52, 61, 55, 16, and 53 in those with cervicitis, HPV 52, 16, 33, 39, and 58 in cervical intraepithelial neoplasia grade 1, HPV 16, 58, 31, 52, and 33 in cervical intraepithelial neoplasia grade 2 or grade 3, and HPV 16, 33, 18, 52, and 58 in cervical cancer. Established high-risk HPV showed two peaks, in patients aged 30-34 and 55-79 years. In Beijing, HPV 16, 52, 58, and 33 are the most prevalent HPV types in women with cervical lesions, which should affect development of a cervical cancer vaccination for local use.
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Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/virologia , Adolescente , Adulto , Idoso , Colo do Útero/patologia , Colo do Útero/virologia , China/epidemiologia , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Papillomaviridae/genética , Infecções por Papillomavirus/patologia , Prevalência , Neoplasias do Colo do Útero/patologia , Adulto JovemRESUMO
BACKGROUND: Serine proteases such as mast cell tryptase and certain allergens are important in the pathogenesis of allergic inflammation of asthma. OBJECTIVE: We sought to investigate the effects of serine protease inhibitors nafamostat mesilate (FUT), gabexate mesilate (FOY), and ulinastatin (UTI) on airway inflammation in a mouse model of allergic asthma. METHODS: BALB/c mice were sensitized to Dermatophagoides pteronyssinus (Der p) and intratracheally challenged with Der p (0.5 mg/mL). Therapeutic doses of FUT (0.0625 mg/kg), FOY (20 mg/kg), and UTI (10,000 U/kg) were intra-peritoneally injected into 3 corresponding sensitized mice during the sensitization phase (protocol 1) or 24 hours after allergen challenge (protocol 2). RESULTS: Both FUT-treated and FOY-treated sensitized mice had reduced mast cells activation, airway hyperresponsiveness, attenuated eosinophils infiltrations, and decreased Der p-induced IL-4 and TNF-alpha, but increased IL-12 cytokine production in bronchoalveolar lavage fluid compared with nontreated mice. Furthermore, FUT treatment downregulated the expression of IL-1beta, TNF-alpha, IL-6, eotaxin, inducible NO synthase, CD86, and nuclear factor-kappaB activation, but enhanced the expression of IL-12 and IL-10 in Der p-stimulated alveolar macrophages. UTI-treated mice have no significant change of the aforementioned measurements compared with nontreated sensitized mice. CONCLUSION: Nafamostat mesilate and FOY exerting the therapeutic effect in allergen-induced airway inflammation was a result not only of their inhibitory action in the early phase of mast cells activation but also of immunoregulatory function in the late phase of allergic inflammation. Such properties of FUT and FOY might be a potential therapeutic approach for asthma. CLINICAL IMPLICATIONS: The clinical used of serine protease inhibitors FUT and FOY may also have implications for treating airway inflammation of asthma.