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1.
Nat Commun ; 11(1): 4018, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32782301

RESUMO

The gut microbiome is an ecosystem that involves complex interactions. Currently, our knowledge about the role of the gut microbiome in health and disease relies mainly on differential microbial abundance, and little is known about the role of microbial interactions in the context of human disease. Here, we construct and compare microbial co-abundance networks using 2,379 metagenomes from four human cohorts: an inflammatory bowel disease (IBD) cohort, an obese cohort and two population-based cohorts. We find that the strengths of 38.6% of species co-abundances and 64.3% of pathway co-abundances vary significantly between cohorts, with 113 species and 1,050 pathway co-abundances showing IBD-specific effects and 281 pathway co-abundances showing obesity-specific effects. We can also replicate these IBD microbial co-abundances in longitudinal data from the IBD cohort of the integrative human microbiome (iHMP-IBD) project. Our study identifies several key species and pathways in IBD and obesity and provides evidence that altered microbial abundances in disease can influence their co-abundance relationship, which expands our current knowledge regarding microbial dysbiosis in disease.


Assuntos
Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais/microbiologia , Consórcios Microbianos , Obesidade/microbiologia , Adulto , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Bactérias/metabolismo , Estudos de Coortes , Disbiose/metabolismo , Disbiose/microbiologia , Feminino , Microbioma Gastrointestinal/genética , Especificidade de Hospedeiro , Humanos , Doenças Inflamatórias Intestinais/metabolismo , Masculino , Redes e Vias Metabólicas , Pessoa de Meia-Idade , Obesidade/metabolismo
2.
PLoS One ; 15(7): e0235740, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32678859

RESUMO

This study evaluated the larvicidal activity of Origanum majorana Linnaeus essential oil, identified the chemical composition, evaluated the antimicrobial, cytotoxic and antioxidant potential. The larvicidal activity was evaluated against larvae of the third stage of Aedes aegypti Linaeus, whereas the chemical composition was identified by gas chromatography coupled to mass spectrometer, the antimicrobial activity was carried out against the bacteria Pseudomonas aeruginosa, Escherichia coli and Staphylococcus auereus, the antioxidant activity was evaluated from of 2.2-diphenyl-1-picryl-hydrazila sequestration and Artemia salina Leach cytotoxicity. Regarding to the results, the larvicidal activity showed that O. majorana L. essential oil caused high mortality in A. aegypti L. larvae. In the chromatographic analysis, the main component found in O. majorana L. essential oil was pulegone (57.05%), followed by the other components verbenone (16.92%), trans-p-menthan-2-one (8.57%), iso-menthone (5.58%), piperitone (2.83%), 3-octanol (2.35%) and isopulegol (1.47%). The antimicrobial activity showed that E. coli and P. aeruginosa bacteria were more sensitive to oil than S. aureus, which was resistant at all concentrations. Essential oil did not present antioxidant activity, but it has high cytotoxic activity against A. salina L.


Assuntos
Aedes/efeitos dos fármacos , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Óleos Voláteis/farmacologia , Origanum/química , Animais , Antibacterianos/química , Antioxidantes/farmacologia , Bactérias/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Folhas de Planta/química , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
3.
Nature ; 583(7816): 453-458, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32669693

RESUMO

Manganese is one of the most abundant elements on Earth. The oxidation of manganese has long been theorized1-yet has not been demonstrated2-4-to fuel the growth of chemolithoautotrophic microorganisms. Here we refine an enrichment culture that exhibits exponential growth dependent on Mn(II) oxidation to a co-culture of two microbial species. Oxidation required viable bacteria at permissive temperatures, which resulted in the generation of small nodules of manganese oxide with which the cells associated. The majority member of the culture-which we designate 'Candidatus Manganitrophus noduliformans'-is affiliated to the phylum Nitrospirae (also known as Nitrospirota), but is distantly related to known species of Nitrospira and Leptospirillum. We isolated the minority member, a betaproteobacterium that does not oxidize Mn(II) alone, and designate it Ramlibacter lithotrophicus. Stable-isotope probing revealed 13CO2 fixation into cellular biomass that was dependent upon Mn(II) oxidation. Transcriptomic analysis revealed candidate pathways for coupling extracellular manganese oxidation to aerobic energy conservation and autotrophic CO2 fixation. These findings expand the known diversity of inorganic metabolisms that support life, and complete a biogeochemical energy cycle for manganese5,6 that may interface with other major global elemental cycles.


Assuntos
Bactérias/metabolismo , Crescimento Quimioautotrófico , Manganês/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Ciclo do Carbono , Dióxido de Carbono/metabolismo , Técnicas de Cocultura , Perfilação da Expressão Gênica , Isótopos , Manganês/química , Compostos de Manganês/química , Compostos de Manganês/metabolismo , Oxirredução , Óxidos/química , Óxidos/metabolismo , Filogenia
4.
Proc Natl Acad Sci U S A ; 117(32): 19446-19454, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32723829

RESUMO

Antimicrobial peptides are important candidates for developing new classes of antibiotics because of their potency against antibiotic-resistant pathogens. Current research focuses on topical applications and it is unclear how to design peptides with systemic efficacy. To address this problem, we designed two potent peptides by combining database-guided discovery with structure-based design. When bound to membranes, these two short peptides with an identical amino acid composition can adopt two distinct amphipathic structures: A classic horizontal helix (horine) and a novel vertical spiral structure (verine). Their horizontal and vertical orientations on membranes were determined by solid-state 15N NMR data. While horine was potent primarily against gram-positive pathogens, verine showed broad-spectrum antimicrobial activity. Both peptides protected greater than 80% mice from infection-caused deaths. Moreover, horine and verine also displayed significant systemic efficacy in different murine models comparable to conventional antibiotics. In addition, they could eliminate resistant pathogens and preformed biofilms. Significantly, the peptides showed no nephrotoxicity to mice after intraperitoneal or intravenous administration for 1 wk. Our study underscores the significance of horine and verine in fighting drug-resistant pathogens.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Sequência de Aminoácidos , Animais , Antibacterianos/metabolismo , Antibacterianos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Infecções Bacterianas/tratamento farmacológico , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Membrana Celular/metabolismo , Bases de Dados de Proteínas , Desenho de Fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Resultado do Tratamento
5.
Food Chem ; 332: 127417, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32629332

RESUMO

The use of UHPH sterilization in the absence of SO2 has been used to eliminate wild microorganisms and inactivate oxidative enzymes. A white must of the Muscat of Alexandria grape variety was continuously processed by UHPH at 300 MPa (inlet temperature: 23-25 °C). The initial microbial load of the settled must was 4-log CFU/mL for both yeast and moulds, and slightly lower for bacteria. After UHPH processing, no microorganisms were detected in 1 mL. UHPH musts remain without fermentative activity for more than 60 days. Concentrations of the thermal markers indicated the absence of thermal damage in the UHPH-treated musts, since 5-hydroxymethylfurfural was not detected. In addition, the must treated by UHPH keeps terpene concentrations similar to those of the untreated controls. A strong inactivation of the oxidative enzymes was observed, with no browning at room temperature for more than 3 days. The antioxidant value of the UHPH-treated must was 156% higher than the control.


Assuntos
Bactérias/crescimento & desenvolvimento , Microbiologia de Alimentos/métodos , Fungos/crescimento & desenvolvimento , Esterilização/métodos , Vinho/análise , Bactérias/enzimologia , Bactérias/metabolismo , Fermentação , Manipulação de Alimentos , Fungos/enzimologia , Fungos/genética , Fungos/metabolismo , Humanos , Dióxido de Enxofre/análise , Paladar , Temperatura , Vitis/química
6.
J Infect Public Health ; 13(10): 1397-1404, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32712106

RESUMO

Secondary bacterial infections are commonly associated with prior or concomitant respiratory viral infections. Viral infections damage respiratory airways and simultaneously defects both innate and acquired immune response that provides a favorable environment for bacterial growth, adherence, and facilitates invasion into healthy sites of the respiratory tract. Understanding the molecular mechanism of viral-induced secondary bacterial infections will provide us a chance to develop novel and effective therapeutic approaches for disease prevention. The present study describes details about the secondary bacterial infection during viral infections and their immunological changes.The outcome of discussion avails an opportunity to understand possible secondary bacterial infections associated with novel SARS-CoV-2, presently causing pandemic outbreak COVID-19.


Assuntos
Infecções Bacterianas/imunologia , Infecções Bacterianas/virologia , Infecções por Coronavirus/imunologia , Influenza Humana/imunologia , Pneumonia Viral/imunologia , Imunidade Adaptativa , Bactérias/crescimento & desenvolvimento , Aderência Bacteriana , Betacoronavirus , Infecções por Coronavirus/complicações , Humanos , Tolerância Imunológica , Imunidade Inata , Inflamação/complicações , Influenza Humana/complicações , Interações Microbianas , Pandemias , Gravidade do Paciente , Pneumonia Viral/complicações
7.
PLoS One ; 15(7): e0235508, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614917

RESUMO

This study examined the influence of bioaugmentation on metal concentrations (aluminum, cadmium, chromium, cobalt, copper, iron, lead, manganese, molybdenum, nickel and zinc) in anaerobically digested sewage sludge. To improve the digestion efficiency, bioaugmentation with a mixture of wild-living Archaea and Bacteria (MAB) from Yellowstone National Park, USA, was used. The total concentration of all metals was higher in the digestate than in the feedstock. During anaerobic digestion, the percent increase in the concentration of most of metals was slightly higher in the bioaugmented runs than in the un-augmented runs, but these differences were not statistically significant. However, the percent increase in cadmium and cobalt concentration was significantly higher in the bioaugmented runs than in the un-augmented runs. At MAB doses of 9 and 13% v/v, cadmium concentration in the digestate was 211 and 308% higher than in the feedstock, respectively, and cobalt concentration was 138 and 165%, respectively. Bioaugmentation increased over 4 times the percentage of Pseudomonas sp. in the biomass that are able to efficiently accumulate metals by both extracellular adsorption and intracellular uptake. Biogas production was not affected by the increased metal concentrations. In conclusion, bioaugmentation increased the concentration of metals in dry sludge, which means that it could potentially have negative effects on the environment.


Assuntos
Metais/metabolismo , Esgotos/química , Adsorção , Anaerobiose , Archaea/genética , Archaea/crescimento & desenvolvimento , Archaea/metabolismo , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Biomassa , Cádmio/análise , Cádmio/metabolismo , Cobalto/análise , Cobalto/metabolismo , Metais/química , Pseudomonas/genética , Pseudomonas/crescimento & desenvolvimento , Pseudomonas/metabolismo , Esgotos/microbiologia , Eliminação de Resíduos Líquidos
8.
Int J Food Microbiol ; 331: 108697, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-32563133

RESUMO

This research investigated the use of high-pressure processing (HPP) for inactivating vegetative pathogens and spoilage microbiota in fresh unfiltered coconut water (Cocos nucifera L) from nuts obtained from Florida and frozen CW from Brazil with pH >5.0 and storage at 4 °C. Additionally, CW was evaluated to determine if it supported the growth and toxin production of Clostridium botulinum with or without the use of HPP when stored at refrigeration temperatures. Samples of fresh unfiltered CW were inoculated to 5.5 to 6.5 logs/mL with multiple strain cocktails of E. coli O157:H7, Salmonella spp. and Listeria monocytogenes and HPP at 593 MPa for 3 min at 4 °C. HPP and inoculated non-HPP controls were stored at 4 °C for 54 and 75 days for Florida CW and Brazil CW, respectively. Results of analyses showed HPP samples with <1 CFU/mL and no detection (negative/25 mL) with enrichment procedures for the 3 inoculated pathogens for all analyses. The non-HPP control samples did not show growth of the pathogens but a gradual decrease in levels to ca. 3-Logs/mL by day 54 in the fresh Florida CW and similarly in frozen Brazil CW by Day 75. Microbial spoilage of uninoculated samples was evaluated for normal spoilage microbiota through 120 days storage at 4 °C. Microbial counts remained at ca. 2-logs with no detectable signs of spoilage for HPP samples through 120 d. The non-HPP control samples spoiled within 2 weeks of storage at 4 °C with gas production, cloudiness, and off-odors. To evaluate if CW supports the growth and toxin production of C. botulinum, samples of unfiltered and filtered (0.2 µm) CW were inoculated with either proteolytic or non-proteolytic C. botulinum spores at 2 log CFU/mL that were processed at 593 MPa for 3 min and stored at 4 °C and 10 °C for 45 days. Inoculated positive and non-inoculated negative controls were prepared and stored as the HPP treated and non-HPP samples. No growth of C. botulinum or toxin production was detected in either the unfiltered or filtered CW regardless if products were HPP treated or not. All inoculated samples with C. botulinum spores were enriched at Day-45 in PYGS media to determine the viability of the inoculated spores at the end of shelf-life and screened for C. botulinum toxins. In all samples, C. botulinum toxin Types A, B and E were detected indicating spores were viable throughout the storage. Type F toxin was not detected possibly due to inherent conditions in the samples that may affected toxin screening.


Assuntos
Fenômenos Fisiológicos Bacterianos , Cocos/microbiologia , Manipulação de Alimentos/métodos , Microbiologia de Alimentos/métodos , Sucos de Frutas e Vegetais/microbiologia , Alimentos Crus/microbiologia , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Brasil , Contagem de Colônia Microbiana , Temperatura
9.
Artigo em Inglês | MEDLINE | ID: mdl-32575528

RESUMO

Background: The aim of the present study is to investigate the role of the colonization of suture thread to identify patients at risk of developing a surgical site infection (SSI) after clean surgical procedures. Methods: Patients who underwent elective clean surgery procedures at the Surgery Unit of the AOU-University of Campania Luigi Vanvitelli in a 21-month period were prospectively enrolled. For each patient, a synthetic absorbable thread in Lactomer 9-1 was inserted into the surgical site at the end of surgery and microbiologically evaluated after 48 h. Antibiotic prophylaxis was chosen according to international guidelines. Results: A total of 238 patients were enrolled; 208 (87.4%) of them were subjected to clean procedures without the placement of prosthesis, and 30 (12.6%) with prosthesis. Of the 238 patients, 117 (49.2%) underwent an antimicrobial prophylaxis. Overall, 79 (33.2%) patients showed a bacterial colonization of the thread: among the 208 without the implantation of prosthesis, 19 (21.8%) of the 87 with antibiotic prophylaxis and in 58 (47.9%) of the 121 without it; among the 30 patients with the implantation of prosthesis, only two patients showed a colonized thread. The patients with antibiotic prophylaxis developed a colonization of the thread less frequently than those without it (17.9% vs. 47.9%, p < 0.001). SSI was observed in six (2.5%) patients, all of them showing a colonized thread (7.6% vs. 0%, p < 0.001). The bacteria identified in colonized threads were the same as those found in SSIs. Conclusions: Our study presents a new method that is able to precociously assess patients who have undergone clean procedures who may develop SSI, and identify the microorganism involved.


Assuntos
Antibacterianos , Antibioticoprofilaxia , Bactérias , Infecção da Ferida Cirúrgica , Suturas , Adulto , Idoso , Idoso de 80 Anos ou mais , Bactérias/crescimento & desenvolvimento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Infecção da Ferida Cirúrgica/microbiologia , Suturas/microbiologia , Adulto Jovem
10.
Ecotoxicol Environ Saf ; 201: 110752, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32474208

RESUMO

Plant is an important part of constructed wetland (CW), while, its potential effect on nitrogen cycling is complicated. Herein, integrated vertical-flow constructed wetland (IVCW) in pilot-scale planted with Arundo donax (Planted System, PS) was constructed to treat swine wastewater. The removal performance of nitrogen in PS, effects of plant on the microbial community structure and nitrogen related function genes were revealed. Results showed that, Arundo donax planting enhanced the removal rate of TN, compared to unplanted IVCWs, the absolute abundance of Pseudomonas, Acinetobacter and Bacillus in PS was significantly increased, as well as the absolute abundance of functional gene (amoA, nxrA, nirK, nirS and nosZ). The denitrification process was mainly occurred in down-flow cell of PS with significantly higher abundant of nirK and nosZ (P < 0.05). These findings suggested that Arundo donax planting in IVCWs with zeolite as substrate promoted the growth of denitrifying microorganisms under higher pollutant load. In addition, the increased abundant of nosZ and the ratio of nosZ/∑nir indicating a lower genetic potential for N2O release. Our research provides new insight into the potential application of plant on the purification of swine wastewater.


Assuntos
Desnitrificação , Poaceae/metabolismo , Águas Residuárias/química , Purificação da Água/métodos , Áreas Alagadas , Animais , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Desnitrificação/genética , Nitrogênio/análise , Nitrogênio/isolamento & purificação , Nitrogênio/metabolismo , Suínos , Águas Residuárias/microbiologia , Zeolitas/metabolismo
11.
Ecotoxicol Environ Saf ; 201: 110739, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32505047

RESUMO

In the study, antibiotic resistance genes (ARGs) were examined in wastewater and sludge samples to explore the effect of cephalexin (CFX) on the spreading and removal of ARGs in the Expanded Granular Sludge Bed (EGSB) reactor treating antibiotics wastewater. The result showed that the addition of CFX in the wastewater affected the removal amount of ß-lactam ARGs and other types ARGs. Besides, the addition of CFX in the wastewater had no obviously effect on total concentration of targeted ARGs in the sludge, but it was related to the accumulation of some typical ARGs. Based on gene cassette array libraries analysis, the diversity of gene cassettes carried by intI1 gene was increased by the addition of CFX in the wastewater. Furthermore, the co-occurrence patterns between ARGs and bacterial genus were also investigated. The results showed the CFX in the wastewater not only affected the number of potential host bacteria of ARGs, but also changed the types of potential host bacteria of ARGs. The correlation analysis of ARG in influent, effluent and sludge showed that, for blaCTX-M, sul2, qnrS and AmpC genes, their removal amount in EGSB reactor treating antibiotic wastewater system might be enhanced by reducing their concentration in the sludge.


Assuntos
Antibacterianos/farmacologia , Cefalexina/farmacologia , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/microbiologia , Antibacterianos/análise , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Cefalexina/análise , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos/efeitos dos fármacos , Esgotos/química , Esgotos/microbiologia , Águas Residuárias/química
12.
Nat Commun ; 11(1): 2719, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483195

RESUMO

National networks of laboratory-based surveillance of antimicrobial resistance (AMR) monitor resistance trends and disseminate these data to AMR stakeholders. Whole-genome sequencing (WGS) can support surveillance by pinpointing resistance mechanisms and uncovering transmission patterns. However, genomic surveillance is rare in low- and middle-income countries. Here, we implement WGS within the established Antimicrobial Resistance Surveillance Program of the Philippines via a binational collaboration. In parallel, we characterize bacterial populations of key bug-drug combinations via a retrospective sequencing survey. By linking the resistance phenotypes to genomic data, we reveal the interplay of genetic lineages (strains), AMR mechanisms, and AMR vehicles underlying the expansion of specific resistance phenotypes that coincide with the growing carbapenem resistance rates observed since 2010. Our results enhance our understanding of the drivers of carbapenem resistance in the Philippines, while also serving as the genetic background to contextualize ongoing local prospective surveillance.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Genoma Bacteriano/genética , Genômica/métodos , Sequenciamento Completo do Genoma/métodos , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Infecções Bacterianas/prevenção & controle , Humanos , Testes de Sensibilidade Microbiana/métodos , Filipinas/epidemiologia , Inquéritos e Questionários
13.
J Med Microbiol ; 69(7): 944-948, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32490795

RESUMO

Introduction. Polymicrobial infections including yeasts and bacteria are not rare and patients with polymicrobial bloodstream infection have higher early and overall case fatality rates. The diagnosis of invasive fungal and bacterial infections is mainly based on blood culture.Aim. The aim was to reveal the effect of concomitant bacteraemia on the detection of fungi from blood cultures in the presence of polymicrobial bloodstream infections involving Candida and non-Candida fungi and to show the superiority of blood culture bottles including selective fungal media in such situations.Methodology. Twenty-four polymicrobial bloodstream infection models - involving one fungus and one bacterium - were constituted by using clinical blood culture isolates (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Candida glabrata, Fusarium solani and Trichosporon asahii). The Plus Aerobic/F (PAF) and Mycosis IC/F (MICF) culture bottles were used with the BACTEC 9240 device. After a bottle signalled positive, direct microscopic examination and subcultures on agar plates were performed.Results. All of fungi that were inoculated alone and in combination were detected by both direct microscopic examination and subcultures on agar plates from MICF bottles, whereas direct microscopic examination only revealed the bacterial agents from PAF bottles including combinations. Furthermore, fungal growth was hidden by bacterial growth on blood agar subcultures from PAF bottles including combinations of F. solani, C. glabrata or T. asahii with bacteria.Conclusion. Blood culture bottles including selective fungal media that can allow selective growth of fungi and earlier detection of some species should be preferred in addition to non-selective blood culture bottles, especially in specific patient populations. Further, the use of selective agar plates such as inhibitory mould agar may contribute to the solution of this problem in clinical laboratories.


Assuntos
Bacteriemia/diagnóstico , Hemocultura/métodos , Bacteriemia/sangue , Bacteriemia/microbiologia , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Infecções Bacterianas/sangue , Infecções Bacterianas/diagnóstico , Candida/isolamento & purificação , Candidemia/sangue , Candidemia/diagnóstico , Candidemia/microbiologia , Meios de Cultura , Fungos/crescimento & desenvolvimento , Fungos/isolamento & purificação , Humanos , Técnicas Microbiológicas/métodos , Micoses/sangue , Micoses/diagnóstico
14.
Ecotoxicol Environ Saf ; 201: 110847, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32554203

RESUMO

Bauxite residues (BR), commonly named red muds, are the saline-sodic waste produced during the extraction of alumina from bauxite. In this study, four kinds of BR were mixed at increasing concentrations with two soils in a mesososm experiment. Unamended BR from Provence (PRO) and Guinea (GUI) bauxite were selected, and Modified Bauxite Residues from PRO and GUI (MBR-PRO and MBR-GUI) were obtained by gypsum application and repeated leaching, in order to reduce their pH, electrical conductivity (EC) and exchangeable sodium percentage (ESP). Several indicators of microbial community functions and structure (growth of culturable bacteria; enzymatic activities; C-sourced substrates degradation (Biolog®); bacteria and fungi PCR-RFLP fingerprints) were measured after 35 days of incubation. Results showed that PRO residue had stronger negative effects than GUI on all the tested indicators. Residues modified by gypsum addition (MBR-PRO, MBR-GUI) were equally or sometimes less harmful compared to unamended residues. Microbial activities (bacterial growth and enzyme activities) were more inhibited than the diversity of microbial functions (Biolog®), and the structure of bacterial and fungal communities was not affected by increasing concentrations of bauxite residues. EC and ESP were the main factors explaining the inhibition of microbial activities, although the origin of bauxite residue is of great importance too.


Assuntos
Óxido de Alumínio/toxicidade , Sulfato de Cálcio/toxicidade , Microbiota/efeitos dos fármacos , Microbiologia do Solo , Poluentes do Solo/toxicidade , Solo/química , Óxido de Alumínio/análise , Óxido de Alumínio/química , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Sulfato de Cálcio/análise , Sulfato de Cálcio/química , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Poluentes do Solo/análise , Poluentes do Solo/química
16.
Stroke ; 51(6): 1844-1854, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32404038

RESUMO

Background and Purpose- Commensal gut bacteria have a profound impact on stroke pathophysiology. Here, we investigated whether modification of the microbiota influences acute and long-term outcome in mice subjected to stroke. Methods- C57BL/6 male mice received a cocktail of antibiotics or single antibiotic. After 4 weeks, fecal bacterial density of the 16S rRNA gene was quantitated by qPCR, and phylogenetic classification was obtained by 16S rRNA gene sequencing. Infarct volume and hemispheric volume loss were measured 3 days and 5 weeks after middle cerebral artery occlusion, respectively. Neurological deficits were tested by the Tape Test and the open field test. Results- Mice treated with a cocktail of antibiotics displayed a significant reduction of the infarct volume in the acute phase of stroke. The neuroprotective effect was abolished in mice recolonized with a wild-type microbiota. Single antibiotic treatment with either ampicillin or vancomycin, but not neomycin, was sufficient to reduce the infarct volume and improved motorsensory function 3 days after stroke. This neuroprotective effect was correlated with a specific microbial population rather than the total bacterial density. In particular, random forest analysis trained for the severity of the brain damage revealed that Bacteroidetes S24.7 and the enzymatic pathway for aromatic metabolism discriminate between large versus small infarct size. Additionally, the microbiota signature in the ampicillin-treated mice was associated with a reduced gut inflammation, long-term favorable outcome shown by an amelioration of the stereotypic behavior, and a reduction of brain tissue loss in comparison to control and was predictive of a regulation of short-chain fatty acids and tryptophan pathways. Conclusions- The findings highlight the importance of the intestinal microbiota in short- and long-term outcomes of ischemic stroke and raises the possibility that targeted modification of the microbiome associated with specific microbial enzymatic pathways may provide a preventive strategy in patients at high risk for stroke. Visual Overview- An online visual overview is available for this article.


Assuntos
Bactérias/crescimento & desenvolvimento , Isquemia Encefálica , Microbioma Gastrointestinal , Doença Aguda , Animais , Bactérias/classificação , Bactérias/genética , Isquemia Encefálica/microbiologia , Isquemia Encefálica/prevenção & controle , Masculino , Camundongos , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Acidente Vascular Cerebral/microbiologia , Acidente Vascular Cerebral/prevenção & controle
17.
Klin Lab Diagn ; 65(6): 375-381, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32459897

RESUMO

When diagnosing bloodstream infection (BI) the culture medium is the basis for growth of microorganisms and obtaining the blood culture. Pancreatic digest from fish meal is the basis of all culture media in Russia. In European countries brain-heart media (BHM) are used for detecting microorganisms in blood. In Russia BHM is not produced. The aim is to work out the formulation and the way of the BHM (broth and agar) preparation in order to improve the efficiency of obtaining blood culture. There were defined the physical and chemical indices and biological parameters of the BHM. The microbiological control of the BHM was carried out by diagnostic study of cardiological patients' blood. On the basis of the developed technique of the brain-heart extraction (BHE) preparation there was created the liquid and agar BHM (LBHM, BHA). The LBHM was poured into bottles which then were filled with the inert gas. The bottles were closed with rubber stoppers and rolled in metal caps became a closed system. Microbiological qualities of LBHM were tested on 260 blood samples and thioglycollate medium (TGM) and LBHM. Aerobic microorganisms grew in LBHM 2,4 times more often than in TGM. The microaerophilic microbes grew in LBHM 3,2 times more often than in TGM. Anaerobic microbes did not show any growth in TGM, (p<0,001). Monomicrobes hemocultures were obtained in LBHM 13,4 times more often than in glucose broth and 2,3 times more often than in TGM, (p<0,001). Polymicrobes hemocultures were obtained in LBHM more often than in TGM (7,3% and 1,7%, respectively). The quality of brain-heart agar (BHA) was tested on 300 blood samples in 5% blood meat-pepton agar (MPA) and BHA in aerobic and anaerobic conditions for both the media. Aerobic microorganisms grew in BHA 2 times more often than in MPA. The microaerophilic microbes grew in BHA 3,6 times more often than in MPA. In anaerobic condition in BHA aerobic microorganisms grew 2 times more often than in MPA and the microaerophilic microbes grew 2,5 times more often than in MPA, (p<0,001). Anaerobic microbes did not grow in MPA. When diagnosing bloodstream infection the BHM (liquid and agar) are able to create the optimal conditions for the increase of the wide range pathogen growth.


Assuntos
Bactérias/isolamento & purificação , Hemocultura , Meios de Cultura , Ágar , Bactérias/crescimento & desenvolvimento , Encéfalo , Coração , Humanos , Federação Russa
18.
Clin Sci (Lond) ; 134(10): 1107-1125, 2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32400877

RESUMO

There is little information on mucins versus potential regulatory factors in the peripheral airway lumen of long-term smokers with (LTS+) and without (LTS-) chronic obstructive pulmonary disease (COPD). We explored these matters in bronchoalveolar lavage (BAL) samples from two study materials, both including LTS+ and LTS- with a very similar historic exposure to tobacco smoke, and healthy non-smokers (HNSs; n=4-20/group). Utilizing slot blot and immunodetection of processed (filtered and centrifuged), as well as unprocessed BAL samples from one of the materials, we compared the quantity and fraction of large complexes of mucins. All LTS displayed an enhanced (median) level of MUC5AC compared with HNS. LTS- displayed a higher level of large MUC5AC complexes than HNS while LTS+ displayed a similar trend. In all LTS, total MUC5AC correlated with blood leukocytes, BAL neutrophil elastase and net gelatinase activity. Large mucin complexes accounted for most MUC5B, without clear group differences. In all LTS, total MUC5B correlated with total MUC5AC and local bacteria. In the same groups, large MUC5B complexes correlated with serum cotinine. MUC1 was increased and correlated with BAL leukocytes in all LTS whereas MUC2 was very low and without clear group differences. Thus, the main part of MUC5AC and MUC5B is present as large complexes in the peripheral airway lumen and historic as well as current exposure to tobacco smoke emerge as potential regulatory factors, regardless of COPD per se. Bacteria, leukocytes and proteinases also constitute potential regulatory factors, of interest for future therapeutic strategies.


Assuntos
Pulmão/metabolismo , Mucina-5AC/metabolismo , Mucina-1/metabolismo , Complexos Multiproteicos/metabolismo , Fumantes , Fumar/metabolismo , Bactérias/crescimento & desenvolvimento , Lavagem Broncoalveolar , Difusão , Feminino , Gases/metabolismo , Humanos , Pulmão/microbiologia , Masculino , Viabilidade Microbiana , Mucina-2/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Fatores de Tempo
19.
Phys Rev Lett ; 124(17): 174501, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32412279

RESUMO

Very lean hydrogen flames were thought to quench in narrow confined geometries. We show for the first time how flames with very low fuel concentration undergo an unprecedented propagation in narrow gaps: H_{2}-air flames can survive very adverse conditions by breaking the reaction front into isolated flame cells that travel steadily in straight lines or split to perform a fractal-like propagation that resembles the pathway of starving fungi or bacteria. The combined effect of hydrogen mass diffusivity and intense heat losses act as the two main mechanisms that explain the experimental observations.


Assuntos
Hidrogênio/química , Modelos Teóricos , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Fogo , Fungos/crescimento & desenvolvimento , Fungos/metabolismo , Modelos Biológicos , Modelos Químicos
20.
Nat Commun ; 11(1): 2382, 2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32404869

RESUMO

Soil micro-organisms drive the global carbon and nutrient cycles that underlie essential ecosystem functions. Yet, we are only beginning to grasp the drivers of terrestrial microbial diversity and biogeography, which presents a substantial barrier to understanding community dynamics and ecosystem functioning. This is especially true for soil protists, which despite their functional significance have received comparatively less interest than their bacterial counterparts. Here, we investigate the diversification of Pinnularia borealis, a rare biosphere soil diatom species complex, using a global sampling of >800 strains. We document unprecedented high levels of species-diversity, reflecting a global radiation since the Eocene/Oligocene global cooling. Our analyses suggest diversification was largely driven by colonization of novel geographic areas and subsequent evolution in isolation. These results illuminate our understanding of how protist diversity, biogeographical patterns, and members of the rare biosphere are generated, and suggest allopatric speciation to be a powerful mechanism for diversification of micro-organisms.


Assuntos
Biodiversidade , Diatomáceas/crescimento & desenvolvimento , Ecossistema , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Diatomáceas/classificação , Diatomáceas/genética , Evolução Molecular , Geografia , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie
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