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1.
Artigo em Inglês | MEDLINE | ID: mdl-33881979

RESUMO

The genera Catabacter (family 'Catabacteraceae') and Christensenella (family Christensenellaceae) are close relatives within the phylum Firmicutes. Members of these genera are strictly anaerobic, non-spore-forming and short straight rods with diverse phenotypes. Phylogenetic analysis of 16S rRNA genes suggest that Catabacter splits Christensenella into a polyphyletic clade. In an effort to ensure that family/genus names represent monophyletic clades, we performed a whole-genome based analysis of the genomes available for the cultured representatives of these genera: four species of Christensenella and two strains of Catabacter hongkongensis. A concatenated alignment of 135 shared protein sequences of single-copy core genes present in the included strains indicates that C. hongkongensis is indeed nested within the Christensenella clade. Based on their evolutionary relationship, we propose the transfer of Catabacter hongkongensis to the genus Christensenella as Christensenella hongkongensis comb. nov.


Assuntos
Clostridiales/classificação , Genoma Bacteriano , Filogenia , Técnicas de Tipagem Bacteriana , Bacilos Gram-Positivos/classificação
2.
FEMS Microbiol Lett ; 368(8)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33930123

RESUMO

Equol, which produced from daidzein (one of the principal isoflavones), is recognized to be the most resultful in stimulating an estrogenic and antioxidant response. The daidzein transformation was studied during fermentation of five growth media inoculated with feces from a healthy human, and a daidzein conversion strain was isolated. To enrich the bacterial population involved in daidzein metabolism in a complex mixture, fecal samples were treated with antibiotics. The improved propidium monoazide combined with the quantitative polymerase chain reaction (PMAxx-qPCR) assay showed that the ampicillin treatment of samples did result in a reduction of the total visible bacteria counts by 52.2% compared to the treatment without antibiotics. On this basis, the newly isolated rod-shaped, Gram-positive anaerobic bacterium, named strain Y11 (MN560033), was able to metabolize daidzein to equol under anaerobic conditions, with a conversion ratio (equol ratio: the amount of equol produced/amount of supplemented daizein) of 0.56 over 120 h. The 16S rRNA partial sequence of the strain Y11 exhibited 99.8% identity to that of Slackia equolifaciens strain DZE (NR116295). This study will provide new insights into the biotransformation of equol from daidzein by intestinal microbiota from the strain-level and explore the possibility of probiotic interventions.


Assuntos
Bactérias Anaeróbias/classificação , Equol/metabolismo , Bacilos Gram-Positivos/classificação , Isoflavonas/metabolismo , Bactérias Anaeróbias/isolamento & purificação , Bactérias Anaeróbias/metabolismo , Técnicas de Tipagem Bacteriana , Biotransformação , DNA Bacteriano/genética , Fezes/microbiologia , Bacilos Gram-Positivos/isolamento & purificação , Bacilos Gram-Positivos/metabolismo , Humanos , Intestinos/microbiologia , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
3.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33836615

RESUMO

Gram-positive bacteria assemble a multilayered cell wall that provides tensile strength to the cell. The cell wall is composed of glycan strands cross-linked by nonribosomally synthesized peptide stems. Herein, we modify the peptide stems of the Gram-positive bacterium Bacillus subtilis with noncanonical electrophilic d-amino acids, which when in proximity to adjacent stem peptides form novel covalent 5,3-cross-links. Approximately 20% of canonical cell-wall cross-links can be replaced with synthetic cross-links. While a low level of synthetic cross-link formation does not affect B. subtilis growth and phenotype, at higher levels cell growth is perturbed and bacteria elongate. A comparison of the accumulation of synthetic cross-links over time in Gram-negative and Gram-positive bacteria highlights key differences between them. The ability to perturb cell-wall architecture with synthetic building blocks provides a novel approach to studying the adaptability, elasticity, and porosity of bacterial cell walls.


Assuntos
Parede Celular/química , Bacilos Gram-Positivos/química , Peptidoglicano/química , Aminoácidos/química , Aminoácidos/metabolismo , Bacillus subtilis/química , Bacillus subtilis/citologia , Bacillus subtilis/crescimento & desenvolvimento , Bacillus subtilis/metabolismo , Parede Celular/metabolismo , Bactérias Gram-Negativas/química , Bactérias Gram-Negativas/citologia , Bactérias Gram-Negativas/metabolismo , Bacilos Gram-Positivos/citologia , Bacilos Gram-Positivos/crescimento & desenvolvimento , Bacilos Gram-Positivos/metabolismo , Peptidoglicano/metabolismo , Peptidil Transferases/genética , Peptidil Transferases/metabolismo , Fenótipo
4.
J. venom. anim. toxins incl. trop. dis ; 27: e20200027, 2021. tab, graf
Artigo em Inglês | ID: biblio-1287091

RESUMO

Mycobacterium leprae and Mycobacterium lepromatosis are gram-positive bacterial pathogens and the causative agents of leprosy in humans across the world. The elimination of leprosy cannot be achieved by multidrug therapy alone, and highlights the need for new tools and drugs to prevent the emergence of new resistant strains. Methods In this study, our contribution includes the prediction of vaccine targets and new putative drugs against leprosy, using reverse vaccinology and subtractive genomics. Six strains of Mycobacterium leprae and Mycobacterium lepromatosis (4 and 2 strains, respectively) were used for comparison taking Mycobacterium leprae strain TN as the reference genome. Briefly, we used a combined reverse vaccinology and subtractive genomics approach. Results As a result, we identified 12 common putative antigenic proteins as vaccine targets and three common drug targets against Mycobacterium leprae and Mycobacterium lepromatosis. Furthermore, the docking analysis using 28 natural compounds with three drug targets was done. Conclusions The bis-naphthoquinone compound Diospyrin (CID 308140) obtained from indigenous plant Diospyros spp. showed the most favored binding affinity against predicted drug targets, which can be a candidate therapeutic target in the future against leprosy.(AU)


Assuntos
Bacilos Gram-Positivos/patogenicidade , Vacinologia , Mycobacterium leprae/patogenicidade , Mycobacterium lepraemurium/patogenicidade
5.
Int J Syst Evol Microbiol ; 70(8): 4730-4738, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32697189

RESUMO

An obligately alkaliphilic, anaerobic, proteolytic bacterium was isolated from a sample of Tanatar III soda lake sediment (Altai region, Russia) and designated as strain Z-1701T. Cells of strain Z-1701T were short, straight, motile Gram-stain-positive rods. Growth of Z-1701T obligately depended on the presence of sodium carbonate. Strain Z-1701T could utilize various peptides mixtures, such as beef and yeast extracts, peptone, soytone, trypticase and tryptone, as well as such proteins as albumin, gelatin and sodium caseinate. It was able to grow oligotrophically with 0.02 g l-1 yeast extract as the sole energy and carbon source. Carbohydrates did not support the growth of strain Z-1701T. The main products released during the growth of strain Z-1701T on tryptone were formate, acetate and ammonium. Strain Z-1701T was able to reduce ferrihydrite, Fe(III)-EDTA, anthraquinone-2,6-disulfonate and elemental sulfur, using proteinaceous substrates as electron donors. In all cases the presence of the electron acceptor in the medium stimulated growth. The main cellular fatty acids were iso-C15 : 0, iso-C15 : 0 aldehyde, iso-C15 : 1 ω6, C16 : 0, iso-C17 : 0 aldehyde, C16 : 0 aldehyde and C14 : 0. The DNA G+C content of the isolate was 43.9 mol%. Phylogenetic analysis based on the concatenated alignment of 120 protein-marker sequences revealed that strain Z-1701T falls into a cluster with the genus Tindallia, family Clostridiaceae. 16S rRNA gene sequence identity between strain Z-1701T and Tindallia species were 88.3-89.75 %. On the basis of its phenotypic characteristics and phylogenetic position, the novel isolate is considered to be a representative of a novel genus and species for which the name Isachenkonia alkalipeptolytica gen. nov., sp. nov. is proposed, with Z-1701T (=JCM 32929Т=DSM 109060Т=VKM B-3261Т) as its type strain.


Assuntos
Bactérias Anaeróbias/classificação , Compostos Férricos/metabolismo , Lagos/microbiologia , Filogenia , Bactérias Redutoras de Enxofre/classificação , Álcalis , Bactérias Anaeróbias/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Bacilos Gram-Positivos/classificação , Bacilos Gram-Positivos/isolamento & purificação , Concentração de Íons de Hidrogênio , RNA Ribossômico 16S/genética , Federação Russa , Análise de Sequência de DNA , Enxofre/metabolismo , Bactérias Redutoras de Enxofre/isolamento & purificação
6.
Infectio ; 24(2): 133-137, abr.-jun. 2020. tab, graf
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1114854

RESUMO

Resumen La bacteriemia por Clostridium sordellii es infrecuente y usualmente se origina a partir de infecciones de etiología generalmente ginecológica y puerperal, con una mortalidad de aproximadamente el 70%. Existen pocas herramientas para el diagnóstico rápido y oportuno, siendo así la experiencia de tratamiento para este germen muy limitada en otros escenarios, lo que probablemente sea la causa de su alta mortalidad. Presentamos una paciente con antecedente de masa abdominal expansiva de larga data, con diagnóstico por histopatología e inmunohistoquimica compatibles con tumor del estroma gastrointestinal (GIST por sus siglas en inglés) y estudios de extensión que confirman compromiso metastásico hepático, en quien se documenta bacteriemia por Clostridium sordellii.


Abstract Clostridium sordellii bacteriemia is infrequent and usually comes from infections of gynecological and puerperal etiology, with mortality near 70%. There are few tools for rapid and timely diagnosis. Thus, treatment experience for this pathogen is very limited in other scenarios, which is probably the cause of high mortality rates. We describe a patient with a history of expansive abdominal mass, diagnosed with metastasic Gastrointestinal Stromal Tumor (GIST), with Clostridium sordellii bacteremia.


Assuntos
Humanos , Feminino , Idoso , Bacteriemia , Clostridium sordellii , Tumores do Estroma Gastrointestinal , Bacilos Gram-Positivos , Sepse , Neoplasias
7.
Med. clín (Ed. impr.) ; 154(9): 351-357, mayo 2020. tab
Artigo em Espanhol | IBECS | ID: ibc-193216

RESUMO

Una de las prioridades actuales de la Organización Mundial de la Salud son las bacterias multirresistentes, dado que constituyen un problema en todo el mundo por su rápida diseminación, así como por la dificultad de su tratamiento. Además, se asocian a una alta morbilidad, mortalidad y a unos costes económicos elevados. Hay bacterias multirresistentes tanto grampositivas como gramnegativas, destacando entre ellas Pseudomonas aeruginosa y Acinetobacter baumannii resistentes a las carbapenemas, enterobacterias productoras de carbapenemasas, Staphylococcus aureus resistente a la meticilina y/o con sensibilidad intermedia a la vancomicina y Enterococcus faecium (y menos frecuentemente Enterococcus faecalis) resistente a la vancomicina. En esta revisión se comentarán los nuevos antibióticos que se han incorporado en los últimos años al arsenal terapéutico, así como otros antibióticos prometedores que se encuentran en sus últimas fases de desarrollo


One of the current priorities of the World Health Organization is multidrug-resistant bacteria, because they are a global problem due to their rapid spread and the difficulty of their treatment. In addition, they are associated with high morbidity, mortality and high economic costs. There are multidrug-resistant bacteria, both Gram-positive and Gram-negative, including Pseudomonas aeruginosa and Acinetobacter baumannii resistant to carbapenems, enterobacteria producing carbapenemases, Staphylococcus aureus resistant to methicillin and/or with intermediate sensitivity to vancomycin, and Enterococcus faecium (and less frequently Enterococcus faecalis) resistant to vancomycin. This review will comment on the new antibiotics that have been incorporated into the therapeutic arsenal in recent years, as well as other promising antibiotics that are in their final stages of development


Assuntos
Humanos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Tazobactam/uso terapêutico , Bacilos Gram-Positivos/efeitos dos fármacos
8.
Int J Syst Evol Microbiol ; 70(2): 732-737, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31702538

RESUMO

An obligately anaerobic, Gram-stain-positive and coccus-shaped bacterium, designated strain YH-panp20T, was isolated from pig faeces. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that the isolate belongs to the family Erysipelotrichaceae, and is most closely related to Catenisphaera adipataccumulans KCTC 15517T (93.5 % sequence similarity), followed by Faecalitalea cylindroides KCTC 5815T (92.2 %), Faecalicoccus acidiformans KCTC 15521T (90.2 %) and Holdemanella biformis KCTC 5969T (89.6 %). Average nucleotide identity values between YH-panp20T and its closest relatives were lower than 71 %. The G+C content of the isolate was 38.4 mol%, and its cell-wall peptidoglycan was found to be of A1γ type and contained meso-diaminopimelic acid. The predominant fatty acids were C18 : 1 cis 9, C18 : 0 DMA and C16 : 0. The major end-products of glucose fermentation were lactate, acetate and formate. Therefore, based on the phenotypic, phylogenetic and chemotaxonomic properties, a novel genus and species, Absicoccus porci gen. nov., sp. nov., is proposed for isolate YH-panp20T (=KCTC 15747T=JCM 32769T).


Assuntos
Firmicutes/classificação , Filogenia , Suínos/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Fezes/microbiologia , Fermentação , Firmicutes/isolamento & purificação , Bacilos Gram-Positivos/genética , Peptidoglicano/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA
9.
Artigo em Japonês | MEDLINE | ID: mdl-31856572

RESUMO

Identification of bacteria by using MALDI Biotyper is relevant at the species category if Score Value (SV) is not less than 2.000. However, in practical examination, the analysis by MALDI Biotyper frequently produces the multiple candidate bacterial species with SV ≥2.000. In this study, we analyzed the ratio of multiple results among 10,081 specimens and identified the species of bacteria with high frequency of multiple results. Our analysis indicated that 8,129 strains out of 10,081 strains examined from July 2015 to July 2017, showed multiple identification results with MALDI Biotyper, and that multiple result was obtained in 4.9% of gram positive cocci analysis, 5.8% of gram positive rods, 25.4% of gram negative cocci, 16% of gram negative rod, none of fungus. In particular, MALDI Biotyper analysis of Enterobacter spp. (E. cloacae, E. asburiae, E. kobei, etc.), Acinetobacter spp. (A. baumannii, A. nosocomialis, A. pittii etc.), Neisseria spp. (N. flavescens, N. perflava etc.) had high ratios of multiple results. Our data suggests that genetic homology among bacteria results in multiple results of bacteria identification. The mass spectrometer method is the rapid test for bacteria identification. However, for obtaining higher specificity, it is required to combine with other methods. Furthermore, systematic annotation of bacteria is highly recommended.


Assuntos
Bactérias Gram-Negativas , Cocos Gram-Positivos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Bacilos Gram-Positivos , Reprodutibilidade dos Testes
11.
Ribeirão Preto; s.n; 2018. 15 p. ilus, tab.
Tese em Português | Sec. Est. Saúde SP, SESSP-ACVSES, SESSP-PAPSESSP, Sec. Est. Saúde SP | ID: biblio-996668
12.
Oper Neurosurg (Hagerstown) ; 14(6): 681-685, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28961750

RESUMO

BACKGROUND: Intracavernous aneurysms constitute up to 9% of all intracranial aneurysms and 6% are infectious (IIA). First line therapy is a protracted antibiotic course, yet with failure, surgery and endovascular parent vessel sacrifice have been utilized. Reconstructive endovascular therapies have emerged for aneurysm control and may demonstrate a safer therapeutic alternative. OBJECTIVE: To present an IIA treated with a flow-diverting Pipeline stent (ev3 Neurovascular, Irvine, California). METHODS: A 41-yr-old female presented with visual loss, ophthalmoplegia, and cavernous sinus thrombosis with an associated phlegmon. Transsphenoidal evacuation was performed without complication or bleeding and she continued on medical therapy. Two weeks postoperatively, she developed a worsening right third cranial nerve palsy and MRA demonstrated a 1-cm right IIA, not evident on postoperative MRI. Three days of dual antiplatelet therapy preceded successful pipeline embolization. Angiography demonstrated aneurysm obliteration at 3 mo and her right ophthalmoplegia resolved. RESULTS: A literature review identified 6 reported cases of IIAs treated with stent embolization. Only 1 documented a flow-diverting Silk stent used in a child. All lesions were obliterated at follow-up without neurological sequelae. No complication arose with implantation in the setting of infection, and as few as 3 d of dual antiplatelet therapy was sufficient for preprocedural prophylaxis, although in Vivo antiplatelet activity may be more significant. CONCLUSION: We report the first case of an IIA treated with a flow-diverting pipeline stent. These devices preserve native vasculature and neurological function compared to surgical and endovascular vessel sacrifice strategies. They appear to be safe management options for the treatment of IIAs.


Assuntos
Actinomicose/complicações , Aspergilose/complicações , Doenças das Artérias Carótidas/terapia , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Infecções por Bactérias Gram-Positivas/complicações , Aneurisma Intracraniano/terapia , Stents , Adulto , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/microbiologia , Trombose do Corpo Cavernoso/etiologia , Celulite (Flegmão)/etiologia , Celulite (Flegmão)/microbiologia , Celulite (Flegmão)/cirurgia , Descompressão Cirúrgica , Embolização Terapêutica/instrumentação , Emergências , Procedimentos Endovasculares/instrumentação , Desenho de Equipamento , Feminino , Bacilos Gram-Positivos/isolamento & purificação , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/microbiologia , Angiografia por Ressonância Magnética , Oftalmoplegia/etiologia , Tomografia Computadorizada por Raios X
13.
Rev. ADM ; 74(4): 185-188, jul.-ago. 2017. ilus, graf
Artigo em Espanhol | LILACS | ID: biblio-908020

RESUMO

Introducción: en los procedimientos odontológicos se está expuestoa gran cantidad de microorganismos y las intervenciones clínicas provocan un contacto directo o indirecto con éstos, ya sea a través del instrumental, equipo odontológico contaminado con saliva, sangre, exudados, etcétera. Por esta razón debe tomarse en cuenta el tipo de contaminación de las piezas de mano por ser parte del equipo de uso cotidiano para realizar tratamientos odontológicos. Objetivos generales:Determinar la carga bacteriana en las piezas de alta velocidad antes y después de su uso en diferentes clínicas de la Facultad de Odontologíade la UV Región Veracruz. Metodología: Investigación transversal, descriptiva y observacional. Material y métodos: Se seleccionaron al azar 30 piezas de mano de los estudiantes de la Universidad Veracruzana Facultad de Odontología Región Veracruz, a las cuales se tomó una muestra con un hisopo de algodón antes y después de su uso en la práctica dental. Se realizaron cultivos con las muestras obtenidas que se observaron durante tres días seguidos bajo microscopio para comprobar la presencia de colonias bacterianas. Resultados: De las30 piezas antes de ser utilizadas se detectó Bacillus grampositivos en24 por ciento de las muestras; en 20 por ciento Bacillus gramnegativos, en 6 por ciento Streptobacillus gram-positivos; en 20 por ciento Staphylococcus grampositivos; en 3 por ciento Cocobacillus gramnegativos y en 22 por ciento Actinomyces gramnegativos. El restante 2 por ciento no reveló unidades formadoras de colonias (UFC). En un segundo muestreo, 33 por ciento desarrolló Bacillus grampositivos, 10 por cientoBacillus gramnegativos, 20 por ciento adquirió Sthapylococcus grampositivos, 3 por ciento Sthapylococcus gramnegativo y 34 por ciento no reveló UFC. Conclusión:En el primer muestreo se detectaron microorganismos en 98% de laspiezas de mano, mientras que en el segundo muestreo 66% se contaminócon microorganismos y en 34% no se observó contaminación.


Introduction: dental activity is exposed to a lot of microorganisms,and clinical interventions have a direct or indirect contact with them.Whether through the instruments, dental equipment contaminatedwith saliva, blood, etc; so you should take into account the type ofcontamination of handpieces for being the most widely used equipmentfor dental treatment. General Objectives: Determine the bacterialload in high-speed parts before and after being used in diff erentclinical uses in Dentistry School at UV, Veracruz. Methodology:Cross-sectional, descriptive and observational research. Materialand methods: 30 pieces of students from the Universidad VeracruzanaSchool of Dentistry, Veracruz region, which a sample was takenwith a swab to pieces before and after use in dental practice wererandomly selected. Cultures with samples obtained observedduring three days in a row microscope to determine the presenceof bacterial colonies were made. Results: Of the 30 pieces beforebeing used 24% of Bacillus Gram-positive samples were found; 20%Bacillus Gram-negative, Gram-positive Streptobacillus 6%; 20%Gram-positive Staphylococcus, 3% developed Coccobacillus Gramnegativeand 22% Gram negative Actinomyces. The remaining 2%no colony forming units development (UFC). In a second sampling;33% developed Bacillus Gram-positive, Gram-negative Bacillus10%, 20% obtained Sthapylococcus Gram-positive, Gram-negativeSthapylococcus 3% and 34% did not develop colony forming unit(CFU). Conclusion: In the first sampling 98% of the pieces were microorganism growth, while in the second 66% and the presence ofmicroorganisms obtained 34% no development.


Assuntos
Humanos , Equipamentos Odontológicos de Alta Rotação/microbiologia , Equipamentos Odontológicos de Alta Rotação/normas , Controle de Infecções Dentárias/métodos , Tratamento do Canal Radicular/instrumentação , Faculdades de Odontologia , Estudos Transversais , Meios de Cultura , Contagem de Colônia Microbiana/métodos , Epidemiologia Descritiva , Contaminação de Equipamentos/prevenção & controle , Bacilos e Cocos Aeróbios Gram-Negativos/isolamento & purificação , Bacilos Gram-Positivos/isolamento & purificação , México
14.
Foodborne Pathog Dis ; 14(3): 177-187, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28128639

RESUMO

A study was conducted to evaluate Sensititre® Automated Reading and Incubation System 2x System (ARIS), API® (API), and Bruker MALDI-TOF MS (MALDI) bacterial species identification systems using 132 diverse bacterial isolates from bovine milk samples and bulk tank milk received at the Penn State Animal Diagnostic Laboratory. The results were compared with 16S rRNA gene sequence analysis, which served as the reference method for species identification. The ARIS, API, and MALDI identified 0%, 40%, and 33.4% of species classified as Gram-positive rod isolates belonging to genera Arthrobacter, Bacillus, Brachybacterium, Brevibacterium, and Corynebacterium, respectively. It was observed that 76.5%, 93.9%, and 96.9% of catalase-negative, Gram-positive cocci (n = 33; Aerococcus, Enterococcus, Lactococcus, Streptococcus) were correctly identified to the species level by ARIS, API, and MALDI, respectively, while 33.4%, 84.5%, and 97.7% of catalase-positive, Gram-positive cocci (n = 45; Kocuria, Staphylococcus) were correctly identified to their species by ARIS, API, and MALDI, respectively. A total of 48 isolates (Acinetobacter, Citrobacter, Enterobacter, Escherichia, Klebsiella, Pantoea, Pasteurella, Providencia, Pseduomonas, Serratia) of Gram-negative bacteria were examined, of which 85.4%, 93.7%, and 95.8% of the isolates were correctly identified to the species level by ARIS, API, and MALDI, respectively. In our laboratory, the MALDI had the least costs associated with consumables and reagents compared to ARIS, API, and 16S rRNA identification methods. Identification of bacterial species was accomplished in <2 h using MALDI and 24 h for ARIS, API, and 16S rRNA identification systems.


Assuntos
Bactérias Gram-Negativas/isolamento & purificação , Cocos Gram-Positivos/isolamento & purificação , Bacilos Gram-Positivos/isolamento & purificação , Mastite Bovina/diagnóstico , Leite/microbiologia , Animais , Bovinos , Feminino , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Bactérias Gram-Negativas/classificação , Cocos Gram-Positivos/classificação , Bacilos Gram-Positivos/classificação , Mastite Bovina/microbiologia , RNA Ribossômico 16S/isolamento & purificação , Análise de Sequência de RNA , Especificidade da Espécie , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
15.
Infectio ; 21(1): 9-14, ene.-mar. 2017. tab
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-892696

RESUMO

Resumen Objetivos: Estimar la prevalencia y los factores relacionados con la infección por Clostridium difficile en un hospital de alta complejidad en Cali (Colombia). Métodos: Se realizó un estudio de casos y controles en pacientes que consultaron por diarrea o la desarrollaron durante la hospitalización y que tuvieron un resultado positivo en la prueba de PCR para Clostridium difficile. Durante el 2012 a 2014, se incluyeron 29 casos y 58 controles. Resultados: La prevalencia de Clostridium difficile hospitalaria en la institución fue de 10 por 10.000 pacientes hospitalizados; en 3 casos se identificó la cepa NAP1-027. Los factores relacionados a Clostridium difficile fueron la diabetes mellitus (OR = 7,4; IC 95%: 1,1-47,6; p = 0,035), la leucemia (OR: 4,1; IC 95%: 1,0-16,5; p =0,043) y el consumo de antibióticos por más de 7 días (OR = 7,0; IC 95%: 2,3-21,1; p = 0,001). Conclusión: Se confirmó la asociación entre el uso previo de antibióticos y la infección por Clostridium difficile, de acuerdo con lo reportado en la literatura mundial. Este estudio describe por primera vez en nuestro país la cepa hipervirulenta NAP1/O27 en pacientes hospitalizados.


Abstract Objectives: To estimate the prevalence and factors related to infection by Clostridium difficile in a high complexity hospital in Cali, Colombia. Methods: A case and control study was conducted in patients consulting for diarrhea or diarrhea developed during hospitalisation with a positive CRP test result for Clostridium difficile. During 2012-2014, 29 cases and 58 controls were included. Results: The prevalence of Clostridium difficile in the hospital was 10 per 10.000 hospitalised patients, in 3 cases the NAP1/O27 strain was identified. Factors associatedwith Clostridium difficile were diabetes mellitus (OR = 7.4, IC95%: 1.1-47.6, P=.035), leukaemia (OR: 4.1, IC95%: 1,0-16.5, P=.043) and consumption of antibiotics for more than 7 days (OR = 7.0, IC95%: 2,3-21.1, P=.001). Conclusions: This study confirmed the association of Clostridium difficile infection with the use of previous antibiotics, in accordance with that reported in literature. This study describes for the first time in our country the hypervirulent NAP1/O27 in hospitalised patients.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Clostridioides difficile , Infecções por Clostridium/epidemiologia , Prevalência , Bacilos Gram-Positivos , Colômbia , Assistência Hospitalar , Antibacterianos
16.
Insect Biochem Mol Biol ; 81: 62-71, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28017798

RESUMO

Cqm1 and Aam1 are α-glucosidases (EC 3.2.1.20) expressed in Culex quinquefasciatus and Aedes aegypti larvae midgut, respectively. These orthologs share high sequence similarity but while Cqm1 acts as a receptor for the Binary (Bin) insecticidal toxin from Lysinibacillus sphaericus, Aam1 does not bind the toxin, rendering Ae. aegypti refractory to this bacterium. Aam1 is heavily glycosylated, contrasting to Cqm1, but little is known regarding how glycosylation impacts on its function. This study aimed to compare the N-glycosylation patterns and the catalytic activities of Aam1 and Cqm1. Mutant proteins were generated where predicted Aam1 N-glycosylation sites (N-PGS) were either inserted into Cqm1 or abrogated in Aam1. The mutants validated four N-PGS which were found to localize externally on the Aam1 structure. These Aam1 and Cqm1 mutants maintained their Bin binding properties, confirming that glycosylation has no role in this interaction. The α-glucosidase activity of both proteins was next investigated, with Aam1 having a remarkably higher catalytic efficiency, influenced by changes in glycosylation. Molecular dynamics showed that glycosylated and nonglycosylated Aam1 models displayed distinct patterns that could influence their catalytic activity. Differential N-glycosylation may then be associated with higher catalytic efficiency in Aam1, enhancing the functional diversity of related orthologs.


Assuntos
Aedes/enzimologia , Culex/enzimologia , alfa-Glucosidases/metabolismo , Animais , Glicosilação , Bacilos Gram-Positivos , Simulação de Dinâmica Molecular
17.
J Clin Lab Anal ; 31(5)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27859671

RESUMO

OBJECTIVES: To evaluate the ability of laser flow cytometry to predict cocci/mixed growth in the pre-analytical phase of urine specimens. METHODS: We retrospectively reviewed urine samples from women with uncomplicated urinary tract infections from urologic clinics for study. Urine analyses were performed with laser flow cytometry (UF1000i, Sysmex, Kobe, Japan) and then diagrams were generated (forward scatter vs. fluorescent light scatter). Each specimen (bacteria count >357 BACT/µL) was classified as either cocci bacteria or rods/mixed growth according to the diagrams. Standard urine cultures were performed, and the agreement between cultures and the UF1000i interpretations was analyzed with kappa statistics. RESULTS: Finally, 491 specimens met the criteria for analysis. Among the 376 specimens with single bacteria growth, there were 26 gram-positive cocci (13 Streptococci spp., 7 Staphylococci spp., 6 Enterococci spp.), 1 gram-positive rods (Corynebacterium spp.), and 349 gram-negative rods (273 Escherichia coli, 33 Klebsiella spp., 29 Proteus spp., 6 Citrobacter spp., 4 Enterobacter spp., 3 Pseudomonas spp., and 1 Providencia spp.). There were 115 specimens with two bacteria species or more that were regarded as mixed growth. Agreement of rods or cocci/mixed growth between the laser flow cytometry and urine cultures yielded a kappa value of 0.58. The positive and negative predictive rate of the UF1000i for cocci/mixed growth in voided urine culture was 81.8% and 84.7%, respectively. CONCLUSIONS: Through laser flow cytometry, we can predict growth of cocci/mixed growth in the pre-analytical phase of urine culture, thus avoiding unnecessary urine culture and waiting time.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Coinfecção/microbiologia , Citometria de Fluxo/métodos , Cocos Gram-Positivos/citologia , Bacilos Gram-Positivos/citologia , Infecções Urinárias/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Coinfecção/diagnóstico , Feminino , Cocos Gram-Positivos/isolamento & purificação , Bacilos Gram-Positivos/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Infecções Urinárias/diagnóstico
18.
J Clin Microbiol ; 54(12): 2928-2936, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27629905

RESUMO

Commensal bacteria from the skin and mucosal surfaces are routinely isolated from patient samples and considered contaminants. The majority of these isolates are catalase-positive Gram-positive rods from multiple genera routinely classified as diphtheroids. These organisms can be seen upon Gram staining of clinical specimens or can be isolated as the predominant or pure species in culture, raising a priori suspicion of a possible involvement in infection. With the development and adoption of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), suspicious isolates are now routinely identified to the species level. In this study, we performed a retrospective data review (2012 to 2015) and utilized site-specific laboratory criteria and chart reviews to identify species within the diphtheroid classification representative of true infection versus contamination. Our data set included 762 isolates from 13 genera constituting 41 bacterial species. Only 18% represented true infection, and 82% were deemed contaminants. Clinically significant isolates were identified in anaerobic wounds (18%), aerobic wounds (30%), blood (5.5%), urine (22%), cerebrospinal fluid (24%), ophthalmologic cultures (8%), and sterile sites (20%). Organisms deemed clinically significant included multiple Actinomyces species in wounds, Propionibacterium species in joints and cerebrospinal fluid associated with central nervous system hardware, Corynebacterium kroppenstedtii (100%) in breast, and Corynebacterium striatum in multiple sites. Novel findings include clinically significant urinary tract infections by Actinomyces neuii (21%) and Corynebacterium aurimucosum (21%). Taken together, these findings indicate that species-level identification of diphtheroids isolated with a priori suspicion of infection is essential to accurately determine whether an isolate belongs to a species associated with specific types of infection.


Assuntos
Bacilos Gram-Positivos/classificação , Bacilos Gram-Positivos/isolamento & purificação , Tipagem Molecular/métodos , Membrana Mucosa/microbiologia , Pele/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Bacilos Gram-Positivos/genética , Humanos , RNA Ribossômico 16S/genética , Estudos Retrospectivos , Análise de Sequência de DNA
19.
Diagn Microbiol Infect Dis ; 85(3): 372-376, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27179368

RESUMO

With the advent of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), most Gram-positive rods (GPRs) are readily identified; however, their clinical relevance in blood cultures remains unclear. Herein, we assessed the clinical significance of GPRs isolated from blood and identified in the era of MALDI-TOF MS. A retrospective chart review of patients presenting to the Mayo Clinic, Rochester, MN, from January 1, 2013, to October 13, 2015, was performed. Any episode of a positive blood culture for a GPR was included. We assessed the number of bottles positive for a given isolate, time to positivity of blood cultures, patient age, medical history, interpretation of culture results by the healthcare team and whether infectious diseases consultation was obtained. We also evaluated the susceptibility profiles of a larger collection of GPRs tested in the clinical microbiology laboratory of the Mayo Clinic, Rochester, MN from January 1, 2013, to October 31, 2015. There were a total of 246 GPRs isolated from the blood of 181 patients during the study period. 56% (n = 101) were deemed contaminants by the healthcare team and were not treated; 33% (n = 59) were clinically determined to represent true bacteremia and were treated; and 8% (n = 14) were considered of uncertain significance, with patients prescribed treatment regardless. Patient characteristics associated with an isolate being treated on univariate analysis included younger age (P = 0.02), identification to the species level (P = 0.02), higher number of positive blood culture sets (P < 0.0001), lower time to positivity (P < 0.0001), immunosuppression (P = 0.03), and recommendation made by an infectious disease consultant (P = 0.0005). On multivariable analysis, infectious diseases consultation (P = 0.03), higher number of positive blood culture sets (P = 0.0005) and lower time to positivity (P = 0.03) were associated with an isolate being treated. 100, 83, 48 and 34% of GPRs were susceptible to vancomycin, meropenem, penicillin and ceftriaxone, respectively.


Assuntos
Antibacterianos/farmacologia , Bacteriemia/microbiologia , Sangue/microbiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Bacilos Gram-Positivos/efeitos dos fármacos , Bacilos Gram-Positivos/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Bacteriemia/epidemiologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/epidemiologia , Bacilos Gram-Positivos/química , Humanos , Testes de Sensibilidade Microbiana , Estudos Retrospectivos
20.
Int J Syst Evol Microbiol ; 66(6): 2225-2233, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26961808

RESUMO

A novel Gram-stain-negative, rod-shaped, facultatively anaerobic, oxidase-negative and catalase-positive bacterium, designated 2W32T, was isolated from a marine solar saltern on the coast of Weihai, Shandong Province, China. Strain 2W32T was tolerant to moderate salt conditions. Optimal growth occurred at 33-37 °C (range 20-45 °C) and pH 7.5-8.0 (range pH 7.0-8.5) with 6-10 % (w/v) NaCl (range 2-18 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain 2W32T shared highest similarity with Aliifodinibius sediminis YIM J21T (94.6 %), Aliifodinibius roseus YIM D15T (94.4 %), Fodinibius salinus YIM C003T (93.6 %), Gracilimonas tropica CL-CB462T (88.6 %) and Balneola vulgaris 13IX/A01/164T (86.4 %) and less than 83.0 % similarity with other species of the phylum Bacteroidetes. The isolate and closely related species formed a novel family-level clade in the phylum Bacteroidetes. The polar lipid profile of the novel isolate consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an unidentified aminolipid, an unidentified glycolipid and an unidentified lipid. The dominant cellular fatty acids (>10 %) were iso-C15 : 0, iso-C17 : 1ω9c and summed feature 3 (C16:1ω7c and/or iso-C15 : 0 2-OH) and the sole respiratory quinone was menaquinone 7 (MK-7). The DNA G+C content of strain 2W32T was 47.5 mol %. Comparative analysis of 16S rRNA gene sequences and characterization indicated that strain 2W32T represents a novel species within the genus Aliifodinibius, for which the name Aliifodinibius halophilus sp. nov. is proposed. The type strain is 2W32T (=KCTC 42497T=CICC 23869T). In addition, a novel family, Balneolaceae fam. nov., is proposed to accommodate the genera Fodinibius, Aliifodinibius, Gracilimonas and Balneola.


Assuntos
Bacteroidetes/classificação , Bacilos Gram-Positivos/classificação , Filogenia , Salinidade , Microbiologia da Água , Técnicas de Tipagem Bacteriana , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Bacilos Gram-Positivos/genética , Bacilos Gram-Positivos/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
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