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1.
Extremophiles ; 20(4): 461-70, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27240672

RESUMO

Endolichenic fungi within 17 lichen species in the area near Ny-Ålesund (Svalbard, High Arctic) were studied by a culture-based method. The 247 fungal isolates were obtained from 2712 lichen thallus segments. The colonization rate of endolichenic fungi ranged from 1.6 to 26.5 %, respectively. These isolates were identified to 40 fungal taxa, including 35 Ascomycota (10 orders), 4 Basidiomycota (3 orders), and 1 unidentified fungus. Thelebolales was the most abundant order, while Sordariales were the most diverse order. The common fungal taxa shared by more than 3 lichen species were Thelebolus microsporus (93 isolates), Coniochaeta hoffmannii (7 isolates), Sarocladium kiliense (33 isolates), Coniochaeta sp. 1 (5 isolates), Coniochaeta sp. 4 (28 isolates), and Coniochaeta sp. 2 (5 isolates). Low Sorenson's similarity coefficients were observed among different lichen species, indicating that host-related factor may shape the endolichenic fungal communities in this region. In addition, no endolichenic fungal taxa were previously found in the Antarctica and Austrian Alps, suggesting endolichenic fungal communities in this region might be also shaped by the Arctic climate. The results demonstrate the existence of specific cultured endolichenic fungal species, which may be suitable objects for further study of their possible functional roles in the lichen thalli.


Assuntos
Líquens/classificação , Microbiota , Regiões Antárticas , Líquens/genética , Líquens/isolamento & purificação
2.
Imeta ; 2(4): e138, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38868215

RESUMO

Lichen genus Endocarpon in biological soil crust form was chosen as a model to investigate the bacterial communities for the first time across four vertically distinct strata. Key bacterial microbiota in lichen thallus were discovered, which were gradually filtered and mainly derived from the crust soil, with clear host selection tendency. The study provided key information to better understand the homeostasis maintenance mechanism of the lichen symbiont and community assembly of desert lichen crust.

3.
Plants (Basel) ; 12(17)2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37687418

RESUMO

Biotic and abiotic factors influence the formation of fungal-algal pairings in lichen symbiosis. However, the specific determinants of these associations, particularly when distantly related fungi are involved, remain poorly understood. In this study, we investigated the impact of different drivers on the association patterns between taxonomically diverse lichenized fungi and their trebouxioid symbiotic partners. We collected 200 samples from four biomes and identified 41 species of lichenized fungi, associating them with 16 species of trebouxioid green algae, of which 62% were previously unreported. The species identity of both the fungal and algal partners had the most significant effect on the outcome of the symbiosis, compared to abiotic factors like climatic variables and geographic distance. Some obviously specific associations were observed in the temperate zone; however, the nestedness value was lower in arid regions than in cold, polar, and temperate regions according to interaction network analysis. Cophylogenetic analyses revealed congruent phylogenies between trebouxioid algae and associated fungi, indicating a tendency to reject random associations. The main evolutionary mechanisms contributing to the observed phylogenetic patterns were "loss" and "failure to diverge" of the algal partners. This study broadens our knowledge of fungal-algal symbiotic patterns in view of Trebouxia-associated fungi.

4.
Int J Ophthalmol ; 16(8): 1326-1336, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37602338

RESUMO

AIM: To assess the efficacy versus the adverse effects of various concentrations of atropine in the prevention of myopia in Asian children. METHODS: Databases (PubMed, EMBASE, the Cochrane Library and Web of science) were comprehensively searched from inception to April 2022. Types of studies included were randomized clinical trials (RCTs). The published languages were limited to English. Two researchers assessed the quality of included studies independently using Cochrane risk of bias tool based on the Cochrane Handbook for Systematic Reviews of Interventions. Funnel plots and Egger's test were used for detection of publication bias. Meta-analyses were conducted using STATA (version 15.0; StataCorp). RESULTS: A total of 15 RCTs involving 2268 patients were included in the study. In the atropine group, spherical equivalent progressed at a significantly lower rate [weighted mean difference (WMD)=0.39, 95% confidence interval (CI): 0.23, 0.54] than in the control group. A WMD of 0.15 mm was associated with less axial elongation (95%CI -0.19, -0.10). Different doses showed statistically significant differences (P<0.05) and an improved effect could result from a higher concentration. Changes in photopic pupil size and mesopic pupil size in atropine group is 0.70 mm (95%CI: 0.33, 1.06) and 0.38 mm (95%CI: 0.22, 0.54) more than the control group. In the present Meta-analysis, no changes in accommodative amplitude (AA) were associated with atropine administration. Atropine administration increased the risk of adverse effects by 1.37 times. CONCLUSION: Concentrations of less than 1% atropine are able to effectively retard diopter and axis growth of myopia in Asian children in a dose-dependent manner. Meanwhile, it caused pupil enlargement, but induced no change in the AA within this range. Further study is required to determine the dosage needed to achieve maximum efficacy and minimal side effects.

5.
Int J Ophthalmol ; 16(7): 1041-1046, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37465512

RESUMO

AIM: To evaluate the difference and the correlation between the concentrations of cytokines in the aqueous humor of eyes with macular edema secondary to diabetic retinopathy (DR) or retinal vein occlusion (RVO). METHODS: This is a retrospective case control study. The aqueous humor samples were collected during intravitreal injection of anti-vascular endothelial growth factor (VEGF) for patients diagnosed with macular edema secondary to DR (DME) or RVO (RVO-ME) at Xijing Hospital from August 2021 to July 2022. Meanwhile, aqueous humor samples during vitrectomy from patients with idiopathic macular hole (IMH) were also collected and served as controls. The aqueous humor concentrations of VEGF, platelet-derived factor (PDGF), interleukin (IL)-6, IL-8, IL-18, tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein 1 (MCP-1) were measured with Human Premixed Multi-Analyte Kit (Luminex). The difference of the aqueous cytokines and the correlation between the two diseases were analyzed. RESULTS: A total of 40 eyes of 38 patients were enrolled in the study, including 13 eyes of 11 DME patients (DME group), 16 eyes of 16 RVO-ME patients (RVO-ME group) and 11 eyes of 11 IMH patients (control group). The VEGF, PDGF, IL-6, IL-8, and MCP-1 levels of the aqueous humor were higher in both DME and RVO-ME groups compared with the control group (all P<0.05), the levels of TNF-α was higher in the DME group than in the control group (P<0.05). The VEGF, IL-6, MCP-1, and TNF-α levels in the aqueous humor were significantly higher in the DR group than those in the RVO group (all P<0.05). Correlation analyses revealed that there were complex positive correlations between IL-6, IL-8, IL-18, MCP-1, and TNF-α levels in the aqueous humor of eyes with two diseases. CONCLUSION: Although ischemic and inflammatory factors are similarly involved in the pathogenesis of DME and RVO-ME, the roles of these factors are more significant or more likely to be activated in DR patients, suggesting different treatment strategies should be considered for the two diseases.

6.
J Fungi (Basel) ; 8(10)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36294559

RESUMO

The lichenized fungal genus Astrothelium is an important element of crustose lichen communities in tropical to subtropical forests. Morphological and molecular phylogenetic approaches to investigate species diversity of Astrothelium (Trypetheliaceae) from Southern China were carried out in this study. Bayesian and maximum-likelihood (ML) analyses were generated based on the combined data set of internal transcribed spacer (ITS), partial regions of the nuclear ribosomal large subunit (LSU), and the largest subunit of RNA polymerase II gene sequences (RPB1). The morphological comparison with the known Astrothelium taxa and molecular phylogeny support five new species: Astrothelium jiangxiense sp. nov., A. luminothallinum sp. nov., A. pseudocrassum sp. nov., A. subeustominspersum sp. nov., and A. subrufescens sp. nov. All these species are described and illustrated in detail.

7.
J Fungi (Basel) ; 8(1)2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-35049942

RESUMO

We employed a molecular phylogenetic approach using five markers (ITS, nuSSU, nuLSU, TEF1-α, and RPB2) to assess potential cryptic speciation in foliicolous members of Strigula s.lat. (Strigulaceae), including the recently segregated genera Phylloporis, Puiggariella, Raciborskiella, Racoplaca, and Serusiauxiella, from tropical areas in Asia, with selected materials from the Neotropics as reference. On the basis of combined molecular and phenotypic datasets, two new species of Racoplaca and 10 new species of Strigula s.str. are described: Racoplaca macrospora sp. nov., R. maculatoides sp. nov., Strigula guangdongensis sp. nov., S. intermedia sp. nov., S. laevis sp. nov., S. microcarpa sp. nov., S. pseudoantillarum sp. nov., S. pseudosubtilissima sp. nov., S. pycnoradians sp. nov., S. sinoconcreta sp. nov., S. stenoloba sp. nov., and S. subtilissimoides sp. nov. In addition, we propose the new combination Phylloporis palmae comb. nov. (≡ =Manaustrum palmae) and we validate the earlier combination Racoplaca melanobapha comb. nov. (≡ Verrucaria melanobapha; Strigula melanobapha). Our data clearly indicate a considerable degree of cryptic diversification in foliicolous representatives of Strigula s.lat., particularly in the presumably widespread taxa Strigula antillarum, S. concreta, S. nitidula, and S. smaragdula. Given that these phylogenetic revisions are thus far limited to few regions, we predict that our findings only represent the proverbial tip of the iceberg in this group of lichenized fungi.

8.
PLoS One ; 14(4): e0215039, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30995267

RESUMO

The Gram-negative bacterium Xanthomonas oryzae pv. oryzicola (Xoc) is the causal agent of rice bacterial leaf streak (BLS), one of the most destructive diseases of rice (Oryza sativa L.) that is the important staple crop. Xoc can invade host leaves via stomata and wounds and its type three secretion system (T3SS) is pivotal to its pathogenic lifestyle. In this study, using a novel dual RNA-seq approach, we examined transcriptomes of rice and Xoc in samples inoculated with wild type Xoc GX01 and its T3SS defective strain (T3SD), to investigate the global transcriptional changes in both organisms. Compared with T3SD strain, rice inoculated with wild type Xoc GX01 resulted in significant expression changes of a series of plant defence related genes, including ones altered in plant signalling pathway, and downregulated in phenylalanine metabolism, flavonoid and momilactone biosynthesis, suggesting repression of plant defence response and reduction in both callose deposition and phytoalexin accumulation. Also, some known transcription activator-like effector (TALE) targets were induced by Xoc GX01, e.g. OsSultr3;6 which contributes to rice susceptibility. Some cell elongation related genes, including several expansin genes, were induced by GX01 too, suggesting that Xoc may exploit this pathway to weaken cell wall strength, beneficial for bacterial infection. On the other hand, compared with wild type, the T3SD strain transcriptome in planta was characterized by downregulation of ATP, protein and polysaccharide synthesis, and upregulation of antioxidation and detoxification related genes, revealing that T3SD strain faced serious starvation and oxidation stresses in planta without a functional T3SS. In addition, comparative global transcript profiles of Xoc in planta and in medium revealed an upregulation of virulence factor synthesis and secretion in planta in favour of bacterial infection. Collectively, this study provides a comprehensive representation of cross talk between the host and bacterial pathogen, revealing insights into the Xoc-rice pathogenic dynamic and reveals novel strategies exploited by this important pathogen to cause disease.


Assuntos
Proteínas de Bactérias/genética , Interações Hospedeiro-Patógeno/genética , Oryza/microbiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Fatores de Virulência/genética , Xanthomonas/genética , Proteínas de Bactérias/metabolismo , Resistência à Doença/genética , Oryza/genética , Proteínas de Plantas/metabolismo , RNA-Seq/métodos , Fatores de Virulência/metabolismo , Xanthomonas/classificação
9.
Oncol Rep ; 39(4): 1948-1956, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29484420

RESUMO

Long non­coding RNAs (lncRNAs) have emerged as critical regulators of tumor progression. However, the function and mechanism of lncRNA NEAT1 in oral squamous cell carcinoma (OSCC) are unclear. In the present study, NEAT1 was significantly upregulated in OSCC cells and tissues. High expression of NEAT1 was correlated with advanced TNM stage and poor survival of patients. Using bioinformatics prediction and experimental analysis, we determined that NEAT1 could negatively regulate the expression of miR­365. The expression of miR­365 was decreased in OSCC tissues and inversely correlated with NEAT1 in tumors. Functionally, knockdown of NEAT1 significantly inhibited cell proliferation and invasion and induced cell cycle arrest at the G0/G1 phase and apoptosis, whereas inhibition of miR­365 abolished the suppressive effect of NEAT1 knockdown on cellular processes. RGS20, a direct target of miR­365, could reverse the tumor suppressive role of miR­365 mimic by enhancing cell viability and motility. Moreover, the protein levels of RGS20, cyclin D1, E­cadherin, N­cadherin and vimentin could be regulated by the NEAT1/miR­365 axis. NEAT1 silencing also inhibited tumor growth in vivo. Collectively, we revealed that the NEAT1/miR­365/RGS20 axis may be a novel mechanism or therapeutic strategy for OSCC treatment.


Assuntos
Carcinoma de Células Escamosas/genética , MicroRNAs/genética , Neoplasias Bucais/genética , Proteínas RGS/genética , RNA Longo não Codificante/genética , Adulto , Idoso , Animais , Apoptose/genética , Carcinoma de Células Escamosas/patologia , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , RNA Longo não Codificante/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
10.
MycoKeys ; (41): 107-118, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30429664

RESUMO

The monotypic lichenised genus Anamylopsora (Baeomycetaceae, Baeomycetales), with its single species A.pulcherrima, is distributed in the arid areas of the Northern Hemisphere, including China. In this paper, we introduce another species new to science, Anamylopsorapruinosa. The new species is characterised by a densely pruinose upper surface, abundantly thick and strong rhizines and terricolous habitat. It is also strongly supported by the phylogenetic and species delimitation analyses based on nrDNA ITS sequences, in which A.pruinosa forms well-supported clade separated from A.pulcherrima.

11.
Sci Rep ; 7(1): 7193, 2017 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-28775314

RESUMO

Endocarpon species are key components of biological soil crusts. Phenotypic and systematic molecular analyses were carried out to identify samples of Endocarpon collected from the southeast edge of the Tengger Desert in China. These morphological and molecular analyses revealed two previously undescribed species that form highly supported independent monophyletic clades within Endocarpon. The new taxa were named Endocarpon deserticola sp. nov. and E. unifoliatum sp. nov. Furthermore, our results indicated that the newly developed protein coding markers adenylate kinase (ADK) and ubiquitin-conjugating enzyme h (UCEH) are useful for assessing species boundaries in phylogenic analyses.


Assuntos
Ascomicetos/classificação , Microbiologia do Solo , Ascomicetos/genética , Ascomicetos/ultraestrutura , China , DNA Espaçador Ribossômico , Genes Fúngicos , Metagenoma , Metagenômica/métodos , Filogenia
12.
Sci Rep ; 5: 14850, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26463847

RESUMO

This study assessed the diversity and distribution of fungal communities associated with seven lichen species in the Ny-Ålesund Region (Svalbard, High Arctic) using Roche 454 pyrosequencing with fungal-specific primers targeting the internal transcribed spacer (ITS) region of the ribosomal rRNA gene. Lichen-associated fungal communities showed high diversity, with a total of 42,259 reads belonging to 370 operational taxonomic units (OTUs) being found. Of these OTUs, 294 belonged to Ascomycota, 54 to Basidiomycota, 2 to Zygomycota, and 20 to unknown fungi. Leotiomycetes, Dothideomycetes, and Eurotiomycetes were the major classes, whereas the dominant orders were Helotiales, Capnodiales, and Chaetothyriales. Interestingly, most fungal OTUs were closely related to fungi from various habitats (e.g., soil, rock, plant tissues) in the Arctic, Antarctic and alpine regions, which suggests that living in association with lichen thalli may be a transient stage of life cycle for these fungi and that long-distance dispersal may be important to the fungi in the Arctic. In addition, host-related factors shaped the lichen-associated fungal communities in this region. Taken together, these results suggest that lichens thalli act as reservoirs of diverse fungi from various niches, which may improve our understanding of fungal evolution and ecology in the Arctic.


Assuntos
Fungos/classificação , Fungos/genética , Variação Genética/genética , Líquens/microbiologia , Consórcios Microbianos/genética , Análise de Sequência de DNA/métodos , Sequência de Bases , Fungos/isolamento & purificação , Dados de Sequência Molecular , Noruega , Especificidade da Espécie
13.
Mycobiology ; 38(3): 176-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23956650

RESUMO

The effect of plant hormones on the growth of lichen-forming fungi (LFF) was evaluated. The use of 2,3,5-triiodobenzoic acid and indole-3-butyric acid resulted in a 99% and 57% increase in dry weight of the lichen-forming fungus Nephromopsis ornata. The results suggest that some plant hormones can be used as inducers or stimulators of LFF growth for large-scale culture.

14.
Mycobiology ; 37(3): 189-96, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23983531

RESUMO

A taxonomic study of Peltigera in South Korea was performed. The phylogenetic analysis based on nr DNA internal transcribed spacer sequences suggests that Peltigera is a well-supported monophyletic group. Important characteristics are the phycobiont type of thallus and the vein type at the lower cortex (wide and flat, or narrow and ridged). The vertical or horizontal arrangement of the apothecia is also important in distinguishing species in this genus. Eleven species of Peltigera were revealed and confirmed, which included one new record, P. elisabethae. A description of each species is presented with morphological, anatomic, and chemical characteristics, and comparisons between similar species are made. A key to the species is also presented.

15.
Mycobiology ; 35(2): 45-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24015068

RESUMO

Lecanora muralis was found on the rock along coastal line during the field trip in Jeju island in 2006. Thallus crustose, placodioid, closely adnate, forming orbicular patches; upper surface grayish green, glossy; central lobes areolate, marginal parts plane, edges thin pruinose; lower surface ecorticate; apothecia sessile, lecanorine type, exciple dense and intact when young, and disc plane, but when mature, exciple laciniate, disc protrudent, yellowish brown to orange, 0.5~1.5 mm in diameter; ascospores ellipsoid, simple, colorless, 12.5~15.0 × 5.0~7.5 µm. Usnic acid and zeorin contained in thallus. This is the first record of this species in South Korea.

16.
Mycobiology ; 35(3): 117-23, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24015081

RESUMO

Seventy-two lichen specimens of Cetrelia collected in South Korea since 2003 were examined by both phenotypic and phylogenetic analyses. The phenotypic analysis was based on morphological and chemical characters, and the phylogenetic analysis was based on nrDNA ITS sequences. The result suggested that the presence and absence of isidia, soredia, lobules and medullar reaction C+ or C- are the important characters in the taxonomy of this genus. Four species of Cetrelia, C. chicitae, C. braunsiana, C. japonica, and C. pseudolivetorum have been identified in this study. Description of each species is presented with morphological and chemical characters. A key to the Cetrelia species is also presented.

17.
Mycobiology ; 35(4): 174-9, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24015093

RESUMO

Three species of Coccocarpia have been reported from Korean Peninsular. However, there was no revisional study on this genus before. After careful examination of the specimens deposited in the Korean Lichen Research Institute (KoLRI) and collected from main mountain areas of Korea, two species of Coccocarpia, C. palmicola and C. erythroxyli, have been revealed to occur and confirmed in South Korea. The presence and absence of isidia and apothecia are the most important characters for the South Korean species. We provide the detailed description and illustration of the available two species. A key to the species is also provided.

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