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1.
Fungal Biol ; 122(11): 1077-1097, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30342624

RESUMO

Cortinarius magellanicus Speg. is an edible, ectomycorrhizal fungus, widely distributed in Argentina, Chile and New Zealand. However, earlier studies already indicated that the epithet 'magellanicus' might have been applied in a wide sense, thus circumscribing several species. A neotype was designated by Moser and Horak (1975) due Spegazzini's type was lost. Argentinian Nothofagaceae forests' samples, from autumn of 2017, morphologically recognized as C. magellanicus were used for a phylogenetic analysis, including sequences from type material and closely related species. Our results showed that C. magellanicus represents a complex of species, with at least three phylogenetic lineages, each with strong regionalism and distinct host associations. Cortinarius magellanicus s. str. is restricted to Patagonia of Argentina and Chile. The misidentified reports from New Zealand and Australia represent distinct and different lineages. In the present contribution, the re-description of C. magellanicus is based on neotype material and two new species are proposed. Cortinarius vitreopileatus var. similissimus is described as variety from New Zealand resembling C. magellanicus, however without close phylogenetic relationship to it. The taxonomic delimitation for C. magellanicus species complex is of high relevance due to the abundance of these fungi and their ectomycorrhizal role in Nothofagaceae forests in Gondwanian region.


Assuntos
Cortinarius/isolamento & purificação , Magnoliopsida/microbiologia , Micorrizas/isolamento & purificação , Argentina , Austrália , Chile , Cortinarius/classificação , Cortinarius/genética , Cortinarius/crescimento & desenvolvimento , Ecossistema , Florestas , Micorrizas/classificação , Micorrizas/genética , Micorrizas/crescimento & desenvolvimento , Nova Zelândia , Filogenia , Esporos Fúngicos/classificação , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/isolamento & purificação
2.
Nat Prod Res ; 32(11): 1361-1364, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28669240

RESUMO

Due to the increasing emergence of resistance of bacterial pathogens to current antibiotics, we have examined the marine fungi present in sea sediments obtained 200 m offshore to discover new antibacterial compounds active against multidrug-resistant bacteria. One strain, identified as Emericellopsis minima, was isolated from sediments of Talcahuano Bay (Chile). From the liquid culture of E. minima, we isolated Emerimicin IV, a unique fungal peptaibol that exhibited antibacterial activity. The structure of this compound was assigned by interpretation of 1H NMR and HR-LCMS data. Emerimicin IV showed bacteriostatic activity against clinical isolates of methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecalis with MIC values ranging between 100 and 12.5 µg/mL.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Peptaibols/química , Peptaibols/farmacologia , Antibacterianos/química , Ascomicetos/química , Baías , Chile , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Sedimentos Geológicos/microbiologia , Humanos , Espectroscopia de Ressonância Magnética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Vancomicina/farmacologia
3.
Psychiatr Genet ; 20(1): 25-30, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20010449

RESUMO

BACKGROUND: Disturbances in central serotonin function have been implicated in impulsive and aggressive behavior. A deletion/insertion polymorphism within the 5-HT transporter promoter gene (5-HTTLPR) is thought to be associated with disturbed impulse control, anxiety, and depression. The serotonin transporter (5-HTT) is the primary action site for selective serotonin reuptake inhibitors (SSRIs). Several studies of major depression have shown that the l allele of 5-HTTLPR is associated with better SSRI antidepressant effects than the s allele. METHODS: This study investigates the association between response of impulsivity to treatment with fluoxetine and 5-HTTLPR polymorphism in 49 personality disordered patients. Additionally, we studied TPH1, 5HT1B and 5HT2C receptor polymorphisms as predictors of response in this population. RESULTS: Results reveal that patients with the l/l genotype of 5-HTTLPR had a significantly better response to fluoxetine when compared to s allele carriers, as evaluated on the basis of total (P<0.05) and Aggression subscale (P<0.01) Overt Aggression Scale Modified-score percentage change. There were no significant associations between fluoxetine response and TPH1 (A218C) (-6525 A>G) (-5806 G>T), HTR1B (G861C) and HTR2C (G68C) genotype groups. CONCLUSION: This is the first study assessing the association between these polymorphisms and anti-impulsive response to fluoxetine in personality disorder. As the s genotype is associated with a poorer selective serotonin reuptake inhibitors response in major depression, bulimia nervosa and borderline personality disorder, it could represent a common biological background for SSRI response.


Assuntos
Agressão , Fluoxetina/uso terapêutico , Comportamento Impulsivo/genética , Transtornos da Personalidade/genética , Polimorfismo Genético/genética , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Adolescente , Adulto , Idoso , Agressão/efeitos dos fármacos , Agressão/fisiologia , Alelos , Feminino , Genótipo , Humanos , Comportamento Impulsivo/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Transtornos da Personalidade/tratamento farmacológico , Escalas de Graduação Psiquiátrica , Adulto Jovem
4.
Microb Biotechnol ; 2(6): 613-24, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21255296

RESUMO

The bioleaching of metal sulfide has developed into a very important industrial process and understanding the microbial dynamic is key to advancing commercial bioleaching operations. Here we report the first quantitative description of the dynamic of active communities in an industrial bioleaching heap. Acidithiobacillus ferrooxidans was the most abundant during the first part of the leaching cycle, while the abundance of Leptospirillum ferriphilum and Ferroplasma acidiphilum increased with age of the heap. Acidithiobacillus thiooxidans kept constant throughout the leaching cycle, and Firmicutes group showed a low and a patchy distribution in the heap. The Acidiphilium-like bacteria reached their highest abundance corresponding to the amount of autotrophs. The active microorganisms in the leaching system were determined using two RNA-based sensitive techniques. In most cases, the 16S rRNA copy numbers of At. ferrooxidans, L. ferriphilum, At. thiooxidans and F. acidiphilum, was concomitant with the DNA copy numbers, whereas Acidiphilium-like bacteria and some Firmicutes members did not show a clear correlation between 16S rRNA accumulation and DNA copy numbers. However, the prokaryotic acidophile microarray (PAM) analysis showed active members of Alphaproteobacteria in all samples and of Sulfobacillus genus in older ones. Also, new active groups such as Actinobacteria and Acidobacterium genus were detected by PAM. The results suggest that changes during the leaching cycle in chemical and physical conditions, such as pH and Fe(3+)/Fe(2+) ion rate, are primary factors shaping the microbial dynamic in the heap.


Assuntos
Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Biodiversidade , Cobre/metabolismo , Microbiologia do Solo , Sulfetos/metabolismo , Bactérias/genética , Bactérias/metabolismo , Análise em Microsséries , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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