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1.
Tuberculosis (Edinb) ; 131: 102123, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34555658

RESUMO

BACKGROUND: Macrophages play an important role in the host immune response against mycobacterial infection, and this process is regulated by various factors, including circular RNAs (circRNAs). We intended to explore the role of circ_0001490 in tuberculosis (TB) using Mycobacterium tuberculosis (M.tb)-infected THP-1 macrophages. METHODS: Real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot assay were conducted to measure RNA and protein expression, respectively. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was conducted to analyze the viability of THP-1 macrophages. Flow cytometry was performed to analyze the apoptosis rate of THP-1 macrophages. Enzyme-linked immunosorbent assay (ELISA) was conducted to assess the release of inflammatory cytokines. Colony-forming unit (CFU) assay was conducted to analyze the survival of M.tb in THP-1 macrophages. Intermolecular target interaction was verified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. RESULTS: Circ_0001490 expression was down-regulated in the serum samples of TB patients and M.tb-infected THP-1 macrophages. Circ_0001490 overexpression suppressed M.tb survival and promoted the viability and inflammatory response of THP-1 macrophages. Circ_0001490 interacted with microRNA-579-3p (miR-579-3p), and circ_0001490 overexpression-induced protective effects in M.tb-infected THP-1 macrophages were largely overturned by the overexpression of miR-579-3p. miR-579-3p interacted with the 3' untranslated region (3'UTR) of follistatin-like protein 1 (FSTL1). FSTL1 silencing largely overturned miR-579-3p knockdown-induced effects in M.tb-infected THP-1 macrophages. Circ_0001490 acted as miR-579-3p sponge to up-regulate FSTL1 in THP-1 macrophages. CONCLUSION: In conclusion, our results demonstrated that circ_0001490 suppressed M.tb survival and promoted the viability and inflammatory response of M.tb-infected THP-1 macrophages partly by regulating miR-579-3p/FSTL1 axis.


Assuntos
Proteínas Relacionadas à Folistatina , Macrófagos , MicroRNAs , Mycobacterium , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Apoptose , Proteínas Relacionadas à Folistatina/imunologia , Inflamação , Macrófagos/imunologia , Macrófagos/microbiologia , MicroRNAs/imunologia , Mycobacterium/crescimento & desenvolvimento , Mycobacterium/metabolismo , Tuberculose , Células THP-1
2.
Genes (Basel) ; 12(4)2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33918798

RESUMO

The mycobacterial nonhomologous end-joining pathway (NHEJ) involved in double-strand break (DSB) repair consists of the multifunctional ATP-dependent ligase LigD and the DNA bridging protein Ku. The other ATP-dependent ligases LigC and AEP-primase PrimC are considered as backup in this process. The engagement of LigD, LigC, and PrimC in the base excision repair (BER) process in mycobacteria has also been postulated. Here, we evaluated the sensitivity of Mycolicibacterium smegmatis mutants defective in the synthesis of Ku, Ku-LigD, and LigC1-LigC2-PrimC, as well as mutants deprived of all these proteins to oxidative and nitrosative stresses, with the most prominent effect observed in mutants defective in the synthesis of Ku protein. Mutants defective in the synthesis of LigD or PrimC/LigC presented a lower frequency of spontaneous mutations than the wild-type strain or the strain defective in the synthesis of Ku protein. As identified by whole-genome sequencing, the most frequent substitutions in all investigated strains were T→G and A→C. Double substitutions, as well as insertions of T or CG, were exclusively identified in the strains carrying functional Ku and LigD proteins. On the other hand, the inactivation of Ku/LigD increased the efficiency of the deletion of G in the mutant strain.


Assuntos
Trifosfato de Adenosina/metabolismo , Proteínas de Bactérias/metabolismo , DNA Primase/metabolismo , Ligases/metabolismo , Taxa de Mutação , Mycobacterium/genética , Estresse Oxidativo , Proteínas de Bactérias/genética , DNA Primase/genética , Ligases/genética , Mycobacterium/crescimento & desenvolvimento , Mycobacterium/metabolismo
3.
Chembiochem ; 22(8): 1424-1429, 2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33347676

RESUMO

Synthetic channels with high ion selectivity are attractive drug targets for diseases involving ion dysregulation. Achieving selective transport of divalent ions is highly challenging due their high hydration energies. A small tripeptide amphiphilic scaffold installed with a pybox ligand selectively transports CuII ions across membranes. The peptide forms stable dimeric pores in the membrane and transports ions by a Cu2+ /H+ antiport mechanism. The ligand-induced excellent CuII selectivity as well as high membrane permeability of the peptide is exploited to promote cancer cell death. The peptide's ability to restrict mycobacterial growth serves as seeds to evolve antibacterial strategies centred on selectively modulating ion homeostasis in pathogens. This simple peptide can potentially function as a universal, yet versatile, scaffold wherein the ion selectivity can be precisely controlled by modifying the ligand at the C terminus.


Assuntos
Cobre/metabolismo , Canais Iônicos/antagonistas & inibidores , Mycobacterium/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Oligopeptídeos/farmacologia , Morte Celular/efeitos dos fármacos , Cobre/química , Humanos , Canais Iônicos/metabolismo , Ligantes , Estrutura Molecular , Mycobacterium/crescimento & desenvolvimento , Neoplasias/metabolismo , Neoplasias/patologia , Oligopeptídeos/química
4.
Sci Rep ; 9(1): 16759, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727946

RESUMO

The dynamic interaction of the N- and C-terminal domains of mycobacterial F-ATP synthase subunit ε is proposed to contribute to efficient coupling of H+-translocation and ATP synthesis. Here, we investigate crosstalk between both subunit ε domains by introducing chromosomal atpC missense mutations in the C-terminal helix 2 of ε predicted to disrupt inter domain and subunit ε-α crosstalk and therefore coupling. The ε mutant εR105A,R111A,R113A,R115A (ε4A) showed decreased intracellular ATP, slower growth rates and lower molar growth yields on non-fermentable carbon sources. Cellular respiration and metabolism were all accelerated in the mutant strain indicative of dysregulated oxidative phosphorylation. The ε4A mutant exhibited an altered colony morphology and was hypersusceptible to cell wall-acting antimicrobials suggesting defective cell wall biosynthesis. In silico screening identified a novel mycobacterial F-ATP synthase inhibitor disrupting ε's coupling activity demonstrating the potential to advance this regulation as a new area for mycobacterial F-ATP synthase inhibitor development.


Assuntos
Trifosfato de Adenosina/metabolismo , Mutação , Mycobacterium/crescimento & desenvolvimento , ATPases Translocadoras de Prótons/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Parede Celular , Simulação por Computador , Metabolismo Energético , Modelos Moleculares , Mycobacterium/enzimologia , Mycobacterium/genética , Conformação Proteica , Estrutura Secundária de Proteína , ATPases Translocadoras de Prótons/química , ATPases Translocadoras de Prótons/genética
5.
Int. j. odontostomatol. (Print) ; 13(3): 357-362, set. 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1012436

RESUMO

ABSTRACT: The contamination of the dental units' waterlines is a reality, which can develop individual and collective disorders. The aim of this study was to evaluate the prevalence and resistance profile of bacteria on the internal surfaces of waterlines in a dental clinic from a Dentistry school of a Brazilian university. The design was an exploratory, descriptive study with quantitative and qualitative approach. Samples (n=4) were collected for analysis at different points: the portion closest to the water reservoir of the chair, and the portion closest to the triple syringe. After collection the samples were cultured in BHI medium in an oven for 24-48 h at 37 °C. For the quantitative analysis 1 ml of each sample was used for serial dilution up to the dilution value seven. The colonies were counted after pour plate and the results expressed in UFC/cm2. The qualitative analysis was initiated with the cultivation of Agar Blood, EMB-Levine and Cetrimide Agar for 24 h, and the identification of bacteria was performed by microscopic analyses. The resistance profile was verified by classical antibiogram. The internal surfaces of unit waterlines units exhibited a mean of 2.44 x 109 CFU / cm2. Bacillus subtilis and Pseudomonas aeruginosa were identified. The resistance profile of Pseudomonas aeruginosa indicated sensitivity to all tested antibiotics. A large number of microorganisms was quantified from biofilm accumulated in the dental units' waterlines. However, they were not resistant to classic antibiogram. Better management and application of decontamination protocols for waterlines need to be applied since opportunistic infections may be associated with Pseudomonas aeruginosa.


RESUMEN: La contaminación de líneas de agua en las unidades dentarias es una realidad, generando enfermedades individuales y colectivas. El objetivo de este estudio fue evaluar la prevalencia y resistencia de las bacterias en las zonas internas de las líneas de agua de la Facultad de Odontología de una universidad brasileña. El diseño del estudio fue exploratorio, descriptivo con enfoques cuantitativos y cualitativos. Las muestras para análisis (n=4) fueron selecionadas de distintos lugares: el punto más cercano al sistema de agua del sillón odontológico y el punto más cercano a la jeringa tríplice. Las muestras obtenidas fueron cultivadas en un médio BHI por 24-48 h, en un horno a 37 ºC. Para el análisis cuantitativo, se utilizó 1 ml de cada muestra para dilución hasta el valor siete. Las colonias fueran contadas y los resultados fueron expresados en UFC/cm2. El análisis cualitativo fue iniciado con el cultivo de Agar Sangre, EBM-Levine y Agar Cetrimide por 24 h y la identificación de la bacteria fue realizada por análisis microscópicos. El perfil de resistencia fue verificado por el antibiograma clásico. Las zonas internas de las unidades de líneas de agua mostraron un promédio de 2,44 x 109 UFC/cm2. Bacillus subtilis y Pseudomonas aeruginosa fueron encontrados. El perfil de resistencia de Pseudomonas aeruginosa indicó sensibilidad a todos los antibióticos testados. Un gran número de microorganismos fue cuantificado desde la biopelícula acumulada en las líneas de agua de unidades dentales. Sin embargo, no resistieron al antibiograma clásico. Se requiere una mejor gestión y aplicación de protocolos de decontaminación en las líneas de agua debido a que las infecciones oportunistas puedan estar asociadas a Pseudomonas aeruginosa.


Assuntos
Humanos , Água/efeitos adversos , Biofilmes , Controle de Infecções Dentárias/métodos , Microbiologia da Água , Brasil , Contagem de Colônia Microbiana , Contaminação de Equipamentos/prevenção & controle , Estudos Prospectivos , Equipamentos Odontológicos/microbiologia , Mycobacterium/crescimento & desenvolvimento
6.
J Ethnopharmacol ; 244: 112095, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31325601

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Zingiber officinale (ginger) is a perennial herbaceous plant native in tropical Asia and generally cultivated in most American tropical countries with widespread use in popular medicine. Ginger essential oil (GEO) has been reported to exhibit several biological activities, such as antimicrobial. AIMS OF THE STUDY: The aim of this study was to determine the composition and the property of GEO and related fractions against Mtb and NTM, as well as their cytotoxicity. METHODS AND MATERIALS: GEO was obtained by hydrodistillation and fractionation was performed. Chemical characterization of GEO and fractions were carried out by gas chromatography/mass spectrometry. The antimycobacterial activity was evaluated by resazurin microtiter assay plate and broth microdilution method for Mtb and NTM, respectively. The cytotoxicity in Vero cells was assessed by MTT colorimetric assay. RESULTS: The analyses showed 63 compounds in the GEO sample, characterized by a high number of monoterpenes and sesquiterpenes. GEO fractionation rendered 11 fractions (FR1 to FR11). GEO and fractions minimum inhibitory concentration ranged from 31.25 to >250 µg/mL against Mtb and from 15.6 to >250 µg/mL against NTM. GEO showed better activity against NTM, M. chelonae, and M. abscessus sub. massiliense, than the semi-pure fractions. One fraction (FR5), containing γ-eudesmol as the main compound, was the most active against Mtb and NTM. The GEO and semi-pure fractions cytotoxicity assay showed CC50 63.3 µg/mL, and 36.3-312.5 µg/mL, respectively. CONCLUSIONS: In general, GEO showed a mix of monoterpenes and sesquiterpenes and a better antimycobacterial activity than the semi-pure fractions. Cytotoxic effects of GEO and its fractions should be better investigated.


Assuntos
Antibacterianos/farmacologia , Mycobacterium/efeitos dos fármacos , Óleos Voláteis/farmacologia , Zingiber officinale , Animais , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Monoterpenos/farmacologia , Mycobacterium/crescimento & desenvolvimento , Rizoma , Sesquiterpenos/farmacologia , Células Vero
7.
Int J Mol Sci ; 20(5)2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30818787

RESUMO

In dealing with Mycobacterium tuberculosis, the causative agent of the deadliest human disease-tuberculosis (TB)-utilization of cholesterol as a carbon source indicates the possibility of using cholesterol catabolic genes/proteins as novel drug targets. However, studies on cholesterol catabolism in mycobacterial species are scarce, and the number of mycobacterial species utilizing cholesterol as a carbon source is unknown. The availability of a large number of mycobacterial species' genomic data affords an opportunity to explore and predict mycobacterial species' ability to utilize cholesterol employing in silico methods. In this study, comprehensive comparative analysis of cholesterol catabolic genes/proteins in 93 mycobacterial species was achieved by deducing a comprehensive cholesterol catabolic pathway, developing a software tool for extracting homologous protein data and using protein structure and functional data. Based on the presence of cholesterol catabolic homologous proteins proven or predicted to be either essential or specifically required for the growth of M. tuberculosis H37Rv on cholesterol, we predict that among 93 mycobacterial species, 51 species will be able to utilize cholesterol as a carbon source. This study's predictions need further experimental validation and the results should be taken as a source of information on cholesterol catabolism and genes/proteins involved in this process among mycobacterial species.


Assuntos
Proteínas de Bactérias/genética , Colesterol/metabolismo , Genes Bacterianos , Mycobacterium/genética , Animais , Proteínas de Bactérias/metabolismo , Colesterol/química , Genes Essenciais , Macrófagos/metabolismo , Macrófagos/microbiologia , Redes e Vias Metabólicas , Camundongos , Viabilidade Microbiana/genética , Mycobacterium/crescimento & desenvolvimento , Infecções por Mycobacterium/genética , Infecções por Mycobacterium/microbiologia , Especificidade da Espécie
8.
Benef Microbes ; 10(3): 315-328, 2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-30773930

RESUMO

Bacteriocins are bacterially-produced antimicrobial peptides that have killing activity principally against other relatively closely-related bacteria. Some bacteriocins of the lactic acid bacteria (LAB) have for many years been extensively applied in food biopreservation. However, especially during the last decade, a number of reports have appeared about unanticipated extensions to the generally rather narrow anti-bacterial activity spectrum of some of the LAB bacteriocins and novel applications have been proposed for bacteriocins ranging from controlling the growth of an increasingly-heterogeneous variety of pathogens, including Gram-negative multidrug resistant bacteria, viruses, yeasts, and in particular, difficult to control Mycobacterium spp., to their potential application as anticancer agents. How best can we assess this now rapidly-accumulating stream of reports on potential future applications of bacteriocins? Where is the line between realistic, science-based proposals and highly-speculative fiction and what are the 'critical points' that might help us to draw this line? In this review, we have attempted to analyse a selection of the presently-available data concerning relatively 'unorthodox' (i.e. beyond food preservation) applications of bacteriocins, and, by utilising our set of 'critical points', we endeavour to identify essential or/and missing information that appear crucial for success of the proposed applications.


Assuntos
Bacteriocinas/farmacologia , Lactobacillales/química , Antibacterianos , Antifúngicos , Antineoplásicos , Antivirais , Bacteriocinas/biossíntese , Conservantes de Alimentos , Mycobacterium/efeitos dos fármacos , Mycobacterium/crescimento & desenvolvimento , Nisina/farmacologia , Percepção de Quorum
9.
Sci Rep ; 9(1): 805, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30692563

RESUMO

In this study, complex structured soluble lignin wastewater was treated by electro-microbial system (EMS) using different direct current (DC) application modes (CR (continuous ON), IR12h (12 h-ON/12 h-OFF) and IR2h (2 h-ON/2 h-OFF)), and physiological characteristics and microbial communities were investigated. Results showed that CR, IR12h and IR2h had higher lignin removals, which were almost two times that of the control reactor (R0', no current), and IR2h performed best and stably. Furthermore, IR2h exhibited the lowest ohmic resistance (Rs) of electrode biofilms, which could be explained by its higher abundance of electroactive bacteria. In the activated sludge of EMS, the concentration of dehydrogenase activity (DHA) and electronic transport system (ETS) in IR2h were the highest (1.48 and 1.28 times of R0'), which contributed to its high content of adenosine triphosphate (ATP). The viability of activated sludge was not affected by different DC application modes. Phospholipid fatty acids (PLFA) analysis indicated that IR2h had the maximum content of C15:1 anteiso A, C16:0 and C18:0; CR increased the content of C15:0 anteiso and decreased the content of saturated fatty acids. Genus-level results revealed that lignin-degrading bacteria, Pseudoxanthomonas and Mycobacterium, could be enriched in IR2h and CR, respectively.


Assuntos
Reatores Biológicos/microbiologia , Lignina/análise , Esgotos/microbiologia , Águas Residuárias/análise , Biofilmes , Condutividade Elétrica , Técnicas Eletroquímicas , Microbiota , Mycobacterium/crescimento & desenvolvimento , Mycobacterium/metabolismo , Purificação da Água , Xanthomonadaceae/crescimento & desenvolvimento , Xanthomonadaceae/metabolismo
10.
Toxins (Basel) ; 10(6)2018 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-29848960

RESUMO

Mycobacterium massiliense is a rapid growing, multidrug-resistant, non-tuberculous mycobacteria that is responsible for a wide spectrum of skin and soft tissue infections, as well as other organs, such as the lungs. Antimicrobial peptides had been described as broad-spectrum antimicrobial, chemotactic, and immunomodulator molecules. In this study we evaluated an antimicrobial peptide derived from scorpion Tityus obscurus as an anti-mycobacterial agent in vitro and in vivo. Bioinformatics analyses demonstrated that the peptide ToAP2 have a conserved region similar to several membrane proteins, as well as mouse cathelicidin. ToAP2 inhibited the growth of four M. massiliense strains (GO01, GO06, GO08, and CRM0020) at a minimal bactericidal concentration (MBC) of 200 µM. MBC concentration used to treat infected macrophages was able to inhibit 50% of the bacterial growth of all strains. ToAP2 treatment of infected mice with bacilli reduced the bacterial load in the liver, lung, and spleen, similarly to clarithromycin levels (90%). ToAP2 alone recruited monocytes (F4/80low Gr1), neutrophils (F4/80- Gr1), and eosinophils (F4/80+ Gr1+). ToAP2, together with M. massiliense infection, was able to increase F4/80low and reduce the percentage of F4/80high macrophages when compared with infected and untreated mice. ToAP2 has in vitro anti-microbial activity that is improved in vivo due to chemotactic activity.


Assuntos
Antibacterianos/toxicidade , Peptídeos Catiônicos Antimicrobianos/toxicidade , Mycobacterium/efeitos dos fármacos , Escorpiões , Animais , Antibacterianos/uso terapêutico , Leucócitos/efeitos dos fármacos , Leucócitos/imunologia , Fígado/efeitos dos fármacos , Fígado/microbiologia , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Macrófagos/microbiologia , Camundongos Endogâmicos BALB C , Camundongos Knockout , Mycobacterium/crescimento & desenvolvimento , Infecções por Mycobacterium/tratamento farmacológico , Infecções por Mycobacterium/microbiologia , Baço/efeitos dos fármacos , Baço/microbiologia
11.
Trop Med Int Health ; 23(4): 367-374, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29446860

RESUMO

OBJECTIVES: Diagnosis of tuberculous meningitis (TM) is a challenge in countries with a high burden of the disease and constrained resources and clinical prediction rules (CPRs) could be of assistance. We aimed at developing a CPR for diagnosis of TM in a Latin American setting with high tuberculosis incidence and a concentrated HIV epidemic. METHODS: We enrolled adult patients with clinical suspicion of TM attending two hospitals in Lima, Peru. We obtained information on potential anamnestic, clinical and laboratory predictive findings that are easy to collect and promptly available. We independently diagnosed TM according to a composite reference standard that included a series of microbiological tests. We performed bivariate analysis and constructed a logistic regression model to select the predictive findings associated with TM. With the selected predictors included in the model, we developed a score-based CPR. We assessed its internal validity and diagnostic performance. RESULTS: Of 155 analysed patients, 59 (38%) had TM. The CPR we derived includes three predictors: cough for 14 days or more, 10-500 cells in CSF and adenosine deaminase ≥ 6 U/l in CSF. It classifies patients into high-, moderate- or low-score groups and has an overall area under the ROC curve of 0.87. 59% of patients were assigned to either the high- or the low-score group, permitting prompt decision-making. In patients in the high-score group, it attains a positive likelihood ratio for TM of 10.6 and in patients with low scores, a negative likelihood ratio of 0.10. Bootstrap analysis indicated high internal validity. CONCLUSION: This CPR could support decision-making in patients with clinical suspicion of TM. External validation and further assessment of its clinical impact are necessary before application in other settings.


Assuntos
Tomada de Decisão Clínica , Técnicas de Apoio para a Decisão , Tuberculose Meníngea/diagnóstico , Adenosina Desaminase/líquido cefalorraquidiano , Adulto , Área Sob a Curva , Cidades , Tosse/diagnóstico , Tosse/etiologia , Tomada de Decisões , Feminino , Infecções por HIV , Hospitais , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Mycobacterium/crescimento & desenvolvimento , Peru , Curva ROC , Tuberculose Meníngea/líquido cefalorraquidiano , Tuberculose Meníngea/complicações , Tuberculose Meníngea/microbiologia
12.
Antonie Van Leeuwenhoek ; 111(7): 1209-1223, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29404824

RESUMO

The taxonomic positions of two fast growing mycobacteria (CECT 8778T and CECT 8779T) were established using a polyphasic approach. The strains were shown to have chemotaxonomic, cultural and morphological properties consistent with their classification in the genus Mycobacterium. Multi-locus sequence analyses (MLSA) show that strain CECT 8778T forms a well-supported clade together with the type strains of Mycobacterium aurum, Mycobacterium austroafricanum and Mycobacterium vanbaalenii while strain CECT 8779T presents as a distinct branch that is well separated from its near phylogenetic neighbours; it is also apparent from the MLSA genetic distances that these strains are most closely related to the type strains of Mycobacterium mageritense and M. vanbaalenii, respectively. Digital DNA:DNA hybridization and average nucleotide identity values between each of the strains and its close phylogenetic neighbour are below the 70 and 96% threshold values for definition of prokaryotic species; these results are underpinned by corresponding phenotypic data. Based upon the consensus of the phenotypic and phylogenetic analyses, it can be concluded that the two strains represent novel species within the genus Mycobacterium for which the following names are proposed: Mycobacterium neglectum sp. nov., with the type strain CECT 8778T (BN 3150T = DSM 44756T) and Mycobacterium palauense sp. nov., with the type strain CECT 8779T (= DSM 44914T).


Assuntos
Mycobacterium/classificação , Mycobacterium/isolamento & purificação , DNA Bacteriano/genética , Tipagem de Sequências Multilocus , Mycobacterium/genética , Mycobacterium/crescimento & desenvolvimento , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética
13.
Curr Issues Mol Biol ; 25: 169-198, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28875944

RESUMO

Mycobacteria are intracellular pathogens that have macrophages as their main host cells. However, macrophages are also the primary line of defense against invading microorganisms. To survive in the intracellular compartment, virulent mycobacteria have developed several strategies to modulate the activation and the effector functions of macrophages. Despite this, antigen-specific T cells develop during infection. While T cell responses are critical for protection they can also contribute to the success of mycobacteria as human pathogens, as immunopathology associated with these responses facilitates transmission. Here, we provide a brief overview of different immune-evasion strategies of mycobacteria and their impact on the protective immune response. This understanding will further our knowledge in host-pathogen interactions and may provide critical insights for the development of novel host-specific therapies.


Assuntos
Células Dendríticas/imunologia , Evasão da Resposta Imune , Macrófagos/imunologia , Mycobacterium tuberculosis/imunologia , Mycobacterium/imunologia , Linfócitos T/imunologia , Imunidade Adaptativa , Animais , Citocinas/genética , Citocinas/imunologia , Células Dendríticas/microbiologia , Regulação da Expressão Gênica , Humanos , Imunidade Inata , Macrófagos/microbiologia , Mycobacterium/crescimento & desenvolvimento , Mycobacterium/patogenicidade , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/patogenicidade , Proteínas NLR/genética , Proteínas NLR/imunologia , Fagossomos/imunologia , Transdução de Sinais , Linfócitos T/microbiologia , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia
14.
Einstein (Säo Paulo) ; 16(2): eAO4214, 2018. tab
Artigo em Inglês | LILACS | ID: biblio-953150

RESUMO

ABSTRACT Objective To compare the performance of the Ogawa-Kudoh method with the modified Petroff technique in diagnosis of pulmonary tuberculosis. Methods A total of 205 sputum samples from 166 patients with clinical suspicion or under pulmonary tuberculosis follow-up, seen at a public tertiary care hospital, from July 2014 to July 2016 were used. All samples were simultaneously processed using the Ogawa-Kudoh and modified Petroff decontamination methods, according to the recommendations of the Ministry of Health. In the statistical analysis, the McNemar test and the Kappa index were used, respectively, to compare proportions and verify agreement between data. Results The Ogawa-Kudoh and modified Petroff methods were efficient in mycobacteria detection, with no significant differences in results (p=0.549) and contamination rate of the cultures (p=0.065). The agreement between techniques was considered excellent (Kappa index of 0.877) and Ogawa-Kudoh, as compared to the modified Petroff technique, showed sensitivity of 90.4%, specificity of 96.6%, positive predictive value of 94.3% and negative predictive value of 94.2%. Conclusion The Ogawa-Kudoh technique proved to be sufficiently sensitive and specific for diagnosis of pulmonary tuberculosis, and, therefore, suitable for routine laboratory application. Since it is simple, low-cost and has less technical requirements for biosafety and professional training, Ogawa-Kudoh is an alternative for managers and healthcare professionals to promote the expansion of bacteriological diagnostic coverage of pulmonary tuberculosis.


RESUMO Objetivo Comparar o desempenho do método de Ogawa-Kudoh ao de Petroff modificado no diagnóstico da tuberculose pulmonar. Métodos Utilizaram-se 205 amostras de escarro de 166 pacientes com suspeita clínica ou controle de tuberculose pulmonar atendidos em um hospital público terciário, entre os meses de julho de 2014 a julho de 2016. Todas as amostras foram processadas simultaneamente pelos métodos de descontaminação Ogawa-Kudoh e Petroff modificado, seguindo as recomendações do Ministério da Saúde. Na análise estatística, foi empregado o teste de McNemar, para comparação de proporções, e o índice Kappa, para verificar o grau de concordância entre os dados. Resultados Os métodos Ogawa-Kudoh e Petroff modificado mostraram-se eficientes na detecção de micobactérias, não sendo verificadas discordâncias significativas tanto nas comparações de pares de resultados (p=0,549), como na taxa de contaminação das culturas (p=0,065). O grau de concordância das técnicas foi considerado excelente (índice Kappa de 0,877), e o Ogawa-Kudoh, em relação ao Petroff modificado, apresentou 90,4% de sensibilidade, 96,6% de especificidade, 94,3% de valor preditivo positivo e 94,2% de valor preditivo negativo. Conclusão O método de Ogawa-Kudoh revelou-se suficientemente sensível e específico para o diagnóstico da tuberculose pulmonar e, portanto, adequado para a aplicação na rotina laboratorial. Por ser mais simples, de baixo custo e com menores exigências técnicas de biossegurança e capacitação profissional, o Ogawa-Kudoh apresenta-se como alternativa para gestores e profissionais da área promoverem a ampliação da cobertura diagnóstica bacteriológica da tuberculose pulmonar.


Assuntos
Humanos , Escarro/microbiologia , Tuberculose Pulmonar/diagnóstico , Técnicas Bacteriológicas/métodos , Mycobacterium/isolamento & purificação , Brasil , Meios de Cultura , Mycobacterium/crescimento & desenvolvimento
15.
Einstein (Säo Paulo) ; 16(2): eAO4150, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-953151

RESUMO

ABSTRACT Objective To evaluate the incidence of variant hemoglobins in different health regions. Methods A descriptive, observational, and cross-sectional study with a quantitative approach based on secondary data in the internal records of the neonatal screening service - Laboratório Central de Saúde Pública do Estado do Piauí (PI, Brazil). The variables related to sex, ethnicity and positive diagnosis for variant hemoglobins were analyzed, with further population distribution of hemoglobinopathies among the macroregions of the state. Results A total of 69,180 samples of newborns were analyzed, and 3,747 were diagnosed as hemoglobinopathies, from February 1st, 2014 and December 31st, 2015. Sickle cell trait was the most frequent (4.1%), followed by hemoglobinopathy C in 0.9%; homozygous hemoglobin S cases 0.1% stood out and there were no cases of hemoglobinopathy D in the state. It is also worth noting that the highest frequencies of hemoglobin alterations in Piauí were in males (49.8%) and of parda skin color (38.5%). The region of Piauí presenting the highest incidence of heteroygous variant hemoglobins was Tabuleiros do Alto Parnaíba and Vale do Sambito, due to importance of the region's population Entre Rios. Conclusion Neonatal screening programs are important for screening, orientations regarding health actions and monitoring of families with hemoglobinopathies, in order to reduce morbidity and mortality rates.


RESUMO Objetivo Avaliar a incidência de hemoglobinas variantes em diferentes regiões de saúde. Métodos Estudo descritivo, observacional e transversal com abordagem quantitativa baseada em dados secundários presentes nos registros internos do serviço de triagem neonatal do Laboratório Central de Saúde Pública do Estado do Piauí (PI, Brasil). Foram analisadas as variáveis referentes a sexo, etnia e diagnóstico positivo para hemoglobinas variantes, com posterior distribuição populacional das hemoglobinopatias entre as macrorregiões do Estado. Resultados Foram analisadas 69.180 amostras de recém-nascidos, e 3.747 diagnosticados com hemoglobinopatias, entre 1° de fevereiro de 2014 e 31 de dezembro de 2015. Constatou-se maior ocorrência do traço falciforme em 4,1% da amostra e da hemoglobinopatia C em 0,9%, com destaque para os casos de hemoglobina S em homozigose (0,1%) e ausência de hemoglobinopatia D no Estado. Destacou-se, ainda, o fato de as maiores frequências de alteração hemoglobínica do Piauí estarem presentes em recém-nascidos do sexo masculino (49,8%) e de etnia parda (38,5%). As regiões do Piauí que apresentaram as maiores incidências de hemoglobinas variantes em heterozigose foram Tabuleiros do Alto Parnaíba e Vale do Sambito, devendo-se ressaltar a relevância populacional da região Entre Rios. Conclusão Os programas de triagem neonatal são importantes para rastreamento, orientação de ações de saúde e acompanhamento de famílias acometidas com hemoglobinopatias, a fim de diminuir a morbimortalidade provocada por estas patologias.


Assuntos
Humanos , Escarro/microbiologia , Tuberculose Pulmonar/diagnóstico , Técnicas Bacteriológicas/métodos , Mycobacterium/isolamento & purificação , Brasil , Meios de Cultura , Mycobacterium/crescimento & desenvolvimento
16.
Tuberculosis (Edinb) ; 107: 80-87, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29050776

RESUMO

In vitro analysis of mycobacterial pathogenicity or host susceptibility has traditionally relied on the infection of macrophages, the target cell of mycobacteria, despite difficulties reproducing their antimycobacterial activity. We have employed alternative models, namely whole blood and leukocytes in plasma, from QuantiFERON negative individuals, and performed infections with the pathogenic M. tuberculosis, the less pathogenic M. avium, M. kansasii and M. chelonae and the occasionally pathogenic M. gordonae and M. bovis. The anticoagulant used in blood extraction, heparin or EDTA, had a major influence in the outcome of the infection. Thus, while in the heparinized models a similar number of bacteria were enumerated in the inoculum and after seven days, in the presence of EDTA a killing effect was observed, despite the inhibitory effect of EDTA on cellular functions like the production of cytokines or reactive oxygen species (ROS). A special case was the rapidly growing mycobacteria M. chelonae, that multiplied in heparinized models but was eliminated in models with EDTA. We verified that EDTA is not responsible for the bactericidal effect, but acts as a bacteriostatic agent. Further work will determine whether blood derived models are a better alternative to the classical macrophage.


Assuntos
Atividade Bactericida do Sangue , Leucócitos/microbiologia , Mycobacterium/crescimento & desenvolvimento , Anticoagulantes/farmacologia , Atividade Bactericida do Sangue/efeitos dos fármacos , Coleta de Amostras Sanguíneas/métodos , Quelantes/farmacologia , Citocinas/sangue , Ácido Edético/farmacologia , Heparina/farmacologia , Interações Hospedeiro-Patógeno , Humanos , Leucócitos/imunologia , Leucócitos/metabolismo , Macrófagos/microbiologia , Viabilidade Microbiana , Mycobacterium/classificação , Mycobacterium/efeitos dos fármacos , Mycobacterium/imunologia , Espécies Reativas de Oxigênio/sangue , Fatores de Tempo
17.
Int J Mycobacteriol ; 6(2): 191-192, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28559524

RESUMO

Causes of lytic bone lesions include benign, malignant, and infectious processes. Lytic lesions due to tuberculosis (TB) may closely mimic those due to tumors such as bone cyst, osteoblastoma, osteosarcoma, and metastatic bone disease radiologically. Histopathology and culture help in definitive diagnosis and prompt management. We describe an immunocompetent patient with isolated lytic bone lesion in the distal part of ulna due to TB to make the readers aware of such unusual presentations of TB.


Assuntos
Osteólise/microbiologia , Tuberculose/microbiologia , Adulto , Feminino , Humanos , Mycobacterium/genética , Mycobacterium/crescimento & desenvolvimento , Mycobacterium/isolamento & purificação , Osteólise/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Tuberculose/diagnóstico por imagem
18.
Infect Control Hosp Epidemiol ; 38(6): 705-711, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28473009

RESUMO

OBJECTIVE Heater-cooler units (HCUs) have been shown to be a source of Mycobacterium chimaera infections. For the past year, weekly water samples have been taken from HCUs used at University Hospitals Birmingham (UHB) NHS Foundation Trust. We report the microbial contamination of the HCUs over a year detailing the decontamination regimes applied at UHB to reduce the microbial load. DESIGN Observational study SETTING UHB is a tertiary referral teaching hospital in Birmingham, United Kingdom, that provides clinical services to nearly 1 million patients every year. The UHB Cardiac department is one of the largest in the United Kingdom and provides treatment for adult patients with a wide range of cardiac diseases. METHODS Water samples taken from HCUs used at UHB for cardiopulmonary bypass surgery were sampled over a year to determine the number of microorganisms by membrane filtration. Various decontamination processes were employed throughout the year. RESULTS Varying total viable counts containing a wide variety of microorganisms were obtained from water inside the HCUs. No M. chimaera were isolated after replacement of the HCU internal tubing. Stringent decontamination regimes resulted in degradation of the HCUs and increased TVCs after several months. CONCLUSION More work is required to ensure effective decontamination processes to reduce the microbial load within the HCUs. Our studies indicate that weekly water sampling for TVC will be required indefinitely to monitor the water quality in these units as well as regular replacement of the tubing to control the build-up of biofilm. Infect Control Hosp Epidemiol 2017;38:705-711.


Assuntos
Ar Condicionado/instrumentação , Descontaminação/métodos , Desinfetantes , Calefação/instrumentação , Mycobacterium/crescimento & desenvolvimento , Microbiologia da Água , Carga Bacteriana , Contaminação de Equipamentos , Hospitais de Ensino , Peróxido de Hidrogênio , Ácido Peracético , Hipoclorito de Sódio , Centros de Atenção Terciária
19.
Sci Rep ; 7(1): 982, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-28428627

RESUMO

Chronic administration of glucocorticoids has been shown to render individuals highly susceptible to mycobacterial infection and lead to reactivation of latent bacilli. However, the effect of glucocorticoids on innate anti-mycobacterial defense, especially in macrophages remains largely unknown. Here, we found that glucocorticoids inhibited the innate immune response, antimicrobial nitric oxide production and autophagy in mycobacteria-challenged macrophages. Meanwhile, maturation and acidification of mycobacterial phagosomes were attenuated in RAW264.7 cells after glucocorticoids treatment. Consequently, we observed a glucocorticoid-induced increase in the survival of intracellular mycobacteria in both primary macrophages and cell lines. Glucocorticoids treatment decreased the activation of TBK1 kinase, which promotes the maturation of autophagosomes. Inhibition of TBK1 also decreased the production of nitric oxide. Furthermore, several autophagy-related genes were down-regulated, while activation of the Akt/mTOR signaling pathway was increased after glucocorticoids treatment, which may account for autophagy inhibition during mycobacterial infection. Restoration of autophagy with the agonist rapamycin abolished glucocorticoid-mediated enhancement of mycobacterial survival, suggesting that glucocorticoids blocked anti-mycobacterial defense via autophagy inhibition. Collectively, this study demonstrates that glucocorticoids impair innate antimicrobial autophagy and promote mycobacterial survival in macrophages, which is a novel mechanism for glucocorticoid-mediated immunosuppression. Our findings may provide important clues for tuberculosis prevention.


Assuntos
Autofagia/efeitos dos fármacos , Glucocorticoides/farmacologia , Macrófagos/citologia , Mycobacterium/crescimento & desenvolvimento , Óxido Nítrico/metabolismo , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/microbiologia , Células Cultivadas , Humanos , Imunidade Inata/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/microbiologia , Camundongos , Viabilidade Microbiana , Mycobacterium/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos
20.
Rev. ADM ; 74(1): 6-10, ene.-feb. 2017. tab
Artigo em Espanhol | LILACS | ID: biblio-869346

RESUMO

Las medidas de bioseguridad están predestinadas a reducir el riesgo de transmisión de microorganismos a partir de fuentes de infección reconocidas o no reconocidas en clínicas dentales vinculadas con lacontaminación de los materiales, aparatos y/o instrumentos. Un microorganismo reemergente es el Mycobacterium abscessus, que es unabacteria ambiental que puede ocasionar problemas de salud muy serios, por lo que debe ser controlada y prevenida su transmisión.


Biosafety measures are designed to reduce the risk of transmission ofmicroorganisms from recognized or unrecognized sources of infectionin dental procedures associated with the contamination of materials,apparatus, and/or instruments. One reemerging microorganism isMycobacterium abscessus, which is an environmental bacterium thatcan cause serious health problems and therefore needs to be controlledand prevented.


Assuntos
Humanos , Consultórios Odontológicos/normas , Controle de Infecções Dentárias/métodos , Infecções por Mycobacterium/classificação , Infecções por Mycobacterium/prevenção & controle , Infecções por Mycobacterium/transmissão , Desinfecção/métodos , Monitoramento Ambiental , Infecções Oportunistas Relacionadas com a AIDS/classificação , Infecções Oportunistas Relacionadas com a AIDS/transmissão , Mycobacterium/crescimento & desenvolvimento , Contagem de Colônia Microbiana/métodos
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