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1.
Food Chem Toxicol ; 156: 112405, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34273428

RESUMO

The unique structure of Mycobacterium tuberculosis cell envelope provides impermeable barrier against environmental stimuli. In the situation that this barrier is disturbed Mycobacteria react at the transcriptional and translational level to redirect metabolic processes and to maintain integrity of the cell. In this work we aimed to explore the early metabolic response of M. tuberculosis to tanshinones, which are active antimycobacterial compounds of Salvia miltiorrhiza Bunge root. The investigation of the expression of sigma factors revealed the significant shifts in the general bacterial regulatory network, whereas LC-MS metabolomics evidenced the changes in the composition of bacterial cell envelope and indicated altered metabolic pathways. Tanshinones acted via the disruption of the cell envelope surface and generation of reactive oxygen species. Bacteria responded with overproduction of inner region of outer membrane, fluctuations in the production of glycerophosphoinositolglycans, as well as changes in the levels of mycobactins, accompanied by enrichment of metabolic pathways related to redox balance and repair of damages caused by tanshinones.

2.
mSystems ; 6(3)2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947802

RESUMO

Mycobacterium tuberculosis developed efficient adaptation mechanisms in response to different environmental conditions. This resulted in the ability to survive in human macrophages and in resistance to numerous antibiotics. To get insight into bacterial responses to potent antimycobacterial natural compounds, we tested how usnic acid, a lichen-derived secondary metabolite, would influence mycobacteria at transcriptomic and metabolomic levels. The analysis of expression of sigma factors revealed a profound impact of usnic acid on one of the primary genetic regulatory systems of M. tuberculosis Combined liquid chromatography-mass spectrometry and nuclear magnetic resonance analyses allowed us to observe the perturbations in metabolic pathways, as well as in lipid composition, which took place within 24 h of exposure. Early bacterial response was related to redox homeostasis, lipid synthesis, and nucleic acid repair. Usnic acid treatment provoked disturbances of redox state in mycobacterial cells and increased production of structural elements of the cell wall and cell membrane. In addition, to increase the number of molecules related to restoration of redox balance, the rearrangements of the cell envelope were the first defense mechanisms observed under usnic acid treatment.IMPORTANCE The evaluation of mechanisms of mycobacterial response to natural products has been barely studied. However, it might be helpful to reveal bacterial adaptation strategies, which are eventually crucial for the discovery of new drug targets and, hence, understanding the resistance mechanisms. This study showed that the first-line mycobacterial defense against usnic acid, a potent antimicrobial agent, is the remodeling of the cell envelope and restoring redox homeostasis. Transcriptomic data correlated with metabolomics analysis. The observed metabolic changes appeared similar to those exerted by antibiotics.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33809199

RESUMO

The coronavirus SARS-CoV-2 responsible for the current human COVID-19 pandemic has shown tropism toward different organs with variable efficiency, eyes included. The purpose of this study has been to investigate the presence of detectable SARS-CoV-2 infection in ocular swabs in patients affected by COVID-19. A consecutive series of 74 COVID-19-positive patients (age 21-89) were enrolled at two Polish COVID-19 hospitals for 4 months and were characterized by PCR for the presence of the SARS-CoV-2 genetic material in nasopharyngeal (NP) and ocular swabs, while their respiratory and ocular symptoms were noted. Almost 50% of them presented with severe/critical respiratory involvement, and some degree of eye disease. No tight correlation was observed between the presence of ocular and respiratory symptoms. Three male patients presenting with severe/critical lung disease tested positive in ocular swab, however with mild/moderate ocular symptoms. In conclusion, our study lends further support to the view that overt ocular infection by the SARS-CoV-2 virus is not such a frequent occurrence.


Assuntos
COVID-19 , Infecções por Coronavirus , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Polônia , SARS-CoV-2 , Adulto Jovem
4.
Sci Rep ; 11(1): 3122, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33542424

RESUMO

Sample pooling strategy was intended to determine the optimal parameters for group testing of pooled specimens for the detection of SARS-CoV-2 and process them without significant loss of test usability. Standard molecular diagnostic laboratory equipment, and commercially available centrifugal filters, RNA isolation kits and SARS Cov2 PCR tests were used. The basic idea was to combine and concentrate several samples to the maximal volume, which can be extracted with the single extraction column. Out of 16 tested pools, 12 were positive with cycle threshold (Ct) values within 0.5 and 3.01 Ct of the original individual specimens. The analysis of 112 specimens determined that 12 pools were positive, followed by identification of 6 positive individual specimens among the 112 tested. This testing was accomplished with the use of 16 extractions/PCR tests, resulting in saving of 96 reactions but adding the 40 centrifugal filters. The present study demonstrated that pool testing could detect even up to a single positive sample with Ct value as high as 34. According to the standard protocols, reagents and equipment, this pooling method can be applied easily in current clinical testing laboratories.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , RNA Viral/isolamento & purificação , Manejo de Espécimes/métodos , Humanos , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Sensibilidade e Especificidade
5.
Biomolecules ; 10(3)2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32111061

RESUMO

The antimycobacterial activity of cinnamaldehyde has already been proven for laboratory strains and for clinical isolates. What is more, cinnamaldehyde was shown to threaten the mycobacterial plasma membrane integrity and to activate the stress response system. Following promising applications of metabolomics in drug discovery and development we aimed to explore the mycobacteria response to cinnamaldehyde within cinnamon essential oil treatment by untargeted liquid chromatography-mass spectrometry. The use of predictive metabolite pathway analysis and description of produced lipids enabled the evaluation of the stress symptoms shown by bacteria. This study suggests that bacteria exposed to cinnamaldehyde could reorganize their outer membrane as a physical barrier against stress factors. They probably lowered cell wall permeability and inner membrane fluidity, and possibly redirected carbon flow to store energy in triacylglycerols. Being a reactive compound, cinnamaldehyde may also contribute to disturbances in bacteria redox homeostasis and detoxification mechanisms.


Assuntos
Acroleína/análogos & derivados , Antituberculosos/farmacologia , Cinnamomum zeylanicum/química , Mycobacterium tuberculosis/efeitos dos fármacos , Óleos Voláteis/farmacologia , Acroleína/química , Acroleína/farmacologia , Antituberculosos/química , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Redes e Vias Metabólicas/efeitos dos fármacos , Metabolômica , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/metabolismo , Óleos Voláteis/química , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia
6.
Future Med Chem ; 11(16): 2193-2203, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31538522

RESUMO

The significant increase in the detection of drug-resistant strains of Mycobacterium tuberculosis caused an urgent need for the discovery new antituberculosis drugs. Development of bioinformatics and computational sciences enabled the progress of new strategies leading to design, discovery and identification of a series of interesting drug candidates. In this short review, we would like to present recently discovered compounds targeting important mycobacterial proteins: DNA topoisomerases and the transcriptional repressor of EthA monooxygenase - EthR.


Assuntos
Antituberculosos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Mycobacterium tuberculosis/efeitos dos fármacos , Proteínas Repressoras/antagonistas & inibidores , Inibidores da Topoisomerase/farmacologia , Tuberculose/tratamento farmacológico , Animais , Antituberculosos/química , Antituberculosos/uso terapêutico , Proteínas de Bactérias/metabolismo , DNA Topoisomerases/metabolismo , Desenvolvimento de Medicamentos , Humanos , Mycobacterium tuberculosis/metabolismo , Proteínas Repressoras/metabolismo , Inibidores da Topoisomerase/química , Inibidores da Topoisomerase/uso terapêutico , Tuberculose/microbiologia
7.
Molecules ; 23(9)2018 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-30231479

RESUMO

The purpose of the study was to evaluate the antimycobacterial activity and the possible action mode of cinnamon bark essential oil and its main constituent-cinnamaldehyde-against the Mycobacterium tuberculosis ATCC 25177 strain. Cinnamaldehyde was proved to be the main bioactive compound responsible for mycobacterial growth inhibition and bactericidal effects. The antimycobacterial activity of cinnamaldehyde was found to be comparable with that of ethambutol, one of the first-line anti-TB antibiotics. The selectivity index determined using cell culture studies in vitro showed a high biological potential of cinnamaldehyde. In M. tuberculosis cells exposed to cinnamaldehyde the cell membrane stress sensing and envelope preserving system are activated. Overexpression of clgR gene indicates a threat to the stability of the cell membrane and suggests a possible mechanism of action. No synergism was detected with the basic set of antibiotics used in tuberculosis treatment: ethambutol, isoniazid, streptomycin, rifampicin, and ciprofloxacin.


Assuntos
Acroleína/análogos & derivados , Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Acroleína/química , Acroleína/farmacologia , Antituberculosos/química , Cromatografia Gasosa-Espectrometria de Massas , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Óleos Voláteis/farmacologia
8.
Molecules ; 23(2)2018 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-29382097

RESUMO

The most commonly used plant source of ß-elemene is Curcuma wenyujin Y. H. Chen & C. Ling (syn. of Curcuma aromatic Salisb.) with its content in supercritical CO2 extract up to 27.83%. However, the other rich source of this compound is Nigella damascena L. essential oil, in which ß-elemene accounts for 47%. In this work, the effective protocol for preparative isolation of ß-elemene from a new source-N. damascena essential oil-using high performance counter-current chromatography HPCCC was elaborated. Furthermore, since sesquiterpens are known as potent antimicrobials, the need for finding new agents designed to combat multi-drug resistant strains was addressed and the purified target compound and the essential oil were tested for its activity against a panel of Gram-positive and Gram-negative bacteria, fungi, and mycobacterial strains. The application of the mixture of petroleum ether, acetonitrile, and acetone in the ratio 2:1.5:0.5 (v/v) in the reversed phase mode yielded ß-elemene with high purity in 70 min. The results obtained for antimicrobial assay clearly indicated that N. damascena essential oil and isolated ß-elemene exert action against Mycobacterium tuberculosis strain H37Ra.


Assuntos
Anti-Infecciosos , Mycobacterium tuberculosis/crescimento & desenvolvimento , Nigella damascena/química , Óleos Voláteis/química , Sesquiterpenos , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana , Sesquiterpenos/química , Sesquiterpenos/farmacologia
9.
Molecules ; 23(1)2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29342972

RESUMO

Background: On account of emergence of multi- and extensively drug-resistant Mycobacterium tuberculosis (Mtb) strains, combinations of drugs with natural compounds were tested to search for antibiotic activity enhancers. In this work we studied terpenes (α-pinene, bisabolol, ß-elemene, (R)-limonene, (S)-limonene, myrcene, sabinene), which are the main constituents of essential oil obtained from Mutellina purpurea L., a plant with described antitubercular activity, to investigate their interactions with antibiotics against reference Mtb strains and multidrug-resistant clinical isolates. Methods: The serial dilution method was used to evaluate the minimal inhibitory concentration (MIC) of tested compounds, while the fractional inhibitory concentration index (FICI) was calculated for characterization of interactions. Moreover, IC50 values of tested compounds were determined using monkey kidney epithelial cell line (GMK). Results: The combinations of all studied terpenes with ethambutol or rifampicin resulted in a synergistic interaction. Bisabolol and (R)-limonene decreased the MIC for rifampicin at least two-fold for all tested strains, however no synergistic action was observed against virulent strains. The tested terpenes showed slight (bisabolol) or no cytotoxic effect against normal eukaryotic cells in vitro. Conclusions: The obtained enhanced activity (FICI < 0.5) of ethambutol and rifampicin against H37Ra strain under the influence of the studied terpenes may be correlated to the capability of essential oil constituents to modify bacterial resistance mechanisms in general. The observed differences in avirulent and virulent bacteria susceptibility to terpenes tested separately and in combinations with antibiotics can be correlated with the differences in the cell wall structure between H37Ra mutant and all virulent strains.


Assuntos
Antituberculosos/farmacologia , Produtos Biológicos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Terpenos/farmacologia , Antituberculosos/química , Produtos Biológicos/química , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/genética , Terpenos/química
10.
Food Chem Toxicol ; 112: 145-149, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29288759

RESUMO

In the past few years, there has been a significant increase in detection of drug resistant strains of Mycobacterium tuberculosis. Search for new antimycobacterial drugs brought natural sources with their chemical diversity in focus. Especially essential oils, produced by plants also for toxic effect, are reservoir of potentially antitubercular compounds. In the present work, we exposed M. tuberculosis H37Ra ATCC 25177 strain to some terpenes commonly occurring in essential oils. Gene expression profiling was used to explore possible influence of these compounds on stress sensing and envelope preserving function. Expression of two genes dprE1 involved in cell wall synthesis and clgR responsible for regulation of cell membrane preservation was investigated. We report that two out of five tested compounds: ß-elemene and R-limonene alter expression of dprE1 and clgR genes. These findings indicate various mechanisms of action of essential oils compounds on M. tuberculosis. Especially the clgR expression seemed to be the perfect marker of stress sensing and envelope preserving systems status.


Assuntos
Oxirredutases do Álcool/genética , Antituberculosos/farmacologia , Proteínas de Bactérias/genética , Cicloexenos/farmacologia , Mycobacterium tuberculosis/genética , Óleos Voláteis/farmacologia , Sesquiterpenos/farmacologia , Terpenos/farmacologia , Biomarcadores/metabolismo , Perfilação da Expressão Gênica , Genes Bacterianos , Limoneno , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Transcrição Genética/efeitos dos fármacos
11.
Oxid Med Cell Longev ; 2017: 8692516, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28642814

RESUMO

The dietary supplements with claimed antioxidant activity constitute a substantial part of the dietary supplement market. In this study, we performed the LC-QTOF-MS analysis and investigated the activity profiles of popular antioxidant dietary supplements from different chemical groups in terms of quality control. The commonly used antioxidant tests and statistical analysis revealed that substantial part of the results was comparable if 1 g sample was considered, but while comparing single and daily doses, significant differences in antioxidant values were noticed in all assays. The best antioxidant activity was obtained in ORAC assay (from 142 to 13814 µM of Trolox equivalents per 1 g of sample), and the strongest correlation occurred between TPC and ORAC. The LC-QTOF-MS analysis revealed that catechins were present in samples having the best antioxidant activity and that dietary supplements showing the weakest activity contained very small amount of any chemical constituents.


Assuntos
Antioxidantes/metabolismo , Catequina/metabolismo , Suplementos Nutricionais/análise , Espectrometria de Massas em Tandem/métodos , Antioxidantes/análise , Humanos , Controle de Qualidade , Espécies Reativas de Oxigênio
12.
Med Princ Pract ; 26(2): 108-112, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27883995

RESUMO

OBJECTIVE: In this study, we aimed to describe the influence of natural terpenes on the antimycobacterial activity of first-line tuberculostatic drugs against isolated Mycobacterium tuberculosis. MATERIALS AND METHODS: The natural terpenes used in this study were R-limonene, S-limonene, myrcene, sabinene, α-pinene, and ß-elemene. The values of the minimum inhibitory concentration (MIC) for these terpenes, as well as for combinations of terpenes with tuberculostatic antibiotics (ethambutol, isoniazid, and rifampicin), were determined using a tube log2 dilution method in the range of 125-0.059 µg/mL. RESULTS: S-limonene had a strong synergistic effect with all tested antibiotics (MIC decreased from 16 to 0.475 µg/mL for ethambutol, from 16 to 0.237 µg/mL for rifampicin, and from 32 to 0.475 µg/mL for isoniazid). Combinations of myrcene, R-limonene, ß-elemene, and sabinene with tuberculostatic antibiotics resulted in a decreased MIC of the antibiotics (from 3.9 to 0.475 µg/mL for ethambutol, from 15 to 0.475 µg/mL for isoniazid, and from 0.475 to 0.237 µg/mL for rifampicin) while combinations of α-pinene with ethambutol and isoniazid resulted in increased MIC values (from 16 to 125 µg/mL for ethambutol, and from 32 to 125 µg/mL for isoniazid). Rifampicin had a synergistic increase in activity with all the tested compounds. CONCLUSIONS: Our study showed that terpenes enhance the activity of tuberculostatic antibiotics.


Assuntos
Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Terpenos/farmacologia , Monoterpenos Acíclicos , Alcenos/farmacologia , Monoterpenos Bicíclicos , Cicloexenos/farmacologia , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Etambutol/farmacologia , Humanos , Isoniazida/farmacologia , Limoneno , Testes de Sensibilidade Microbiana , Monoterpenos/farmacologia , Rifampina/farmacologia , Sesquiterpenos/farmacologia
13.
Nat Prod Commun ; 11(7): 1015-1018, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30452185

RESUMO

The major purpose of this study was to determine the chemical relationships between the essential oils (EO) obtained form 18 mint samples of different species and its cultivrs. GC/MS analysis of all essential oils showed that oxygenated monoterpenoids are the major components of these oils, with the exception of Mentha arvensis 'Banana'. Based on the. chemical composition of the essential oils, the analyzed mints can be divided into five groups. Group I was characterized by the-presence of menthol and menthone, piperitenone oxide is the major constituent of group II, linalool of group III, carvone characterizes group IV, while 3-octanone is the most characteristic compound for group V. A reference strain of biofilm forming Staphylococcus epidermidis ATTC 35984 was tested against the obtained essential oils. Two of them, M suaveolens 'Variegata' and M x piperita 'Almira' exhibited significant bacteriostatic activity. The MIC values of these EOs were 0.25% and 0.5% respectively in comparison with an average MIC of 4% of the other tested mint EOs. Both active EOs are characterized by the presence of piperitenone oxide as the major component.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Mentha/química , Óleos Voláteis/química , Óleos Vegetais/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Staphylococcus epidermidis
14.
Med Princ Pract ; 24(6): 527-32, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26381133

RESUMO

OBJECTIVE: The aim of this study was to evaluate the antimycobacterial activity of the essential oil (EO) of Mutellina purpurea L. and its main constituents against the M. tuberculosis H37Ra strain. MATERIALS AND METHODS: The M. purpurea EO was obtained by hydrodistillation, while its main constituents were purchased. The minimal inhibitory concentration values were determined by the log2 dilution method. Visualization of the effects of the tested substances on M. tuberculosis was performed using a transmission electron microscope (TEM). Mathematical shape descriptors such as area, circularity, aspect ratio and roundness were calculated to describe morphological changes in bacterial cell shape. RESULTS: The EO of M.purpurea and all substances tested in this experiment showed a significant antimycobacterial activity. The most active was α-pinene followed by bisabolol and myrcene (8, 16 and 32 µg/ml, respectively). The EO and limonene exhibited the same antimicrobial activity (64 µg/ml). The TEM images and shape descriptors showed significant changes in the overall tuberculosis cell shape and cytoplasm homogeneity (uniformity and consistency) CONCLUSIONS: In this study, the low molecular weight compounds of mono- and sesquiterpenes penetrated/destabilized the complex mycobacterial cell wall and decreased its viability. There is a need for further experiments to explain the mechanism of action of these small particles.


Assuntos
Antibacterianos/farmacologia , Apiaceae , Forma Celular/efeitos dos fármacos , Citoplasma/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Óleos Voláteis/farmacologia , Antibacterianos/química , Monoterpenos Bicíclicos , Cicloexenos/farmacologia , Relação Dose-Resposta a Droga , Humanos , Limoneno , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Sesquiterpenos Monocíclicos , Monoterpenos/farmacologia , Óleos Voláteis/química , Sesquiterpenos/farmacologia , Terpenos/farmacologia
15.
Postepy Kardiol Interwencyjnej ; 10(4): 317-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25489331

RESUMO

This case demonstrates a rare anomalous of origin of right coronary artery from the left sinus of Valsalva in patients who underwent kidney transplantation complicated by an acute ST elevation myocardial infarction treated with delay angioplasty.

16.
Int J Artif Organs ; 36(2): 105-12, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23280080

RESUMO

OBJECTIVES: This study aims to examine biofilm formed on vascular prostheses by Staphylococcus epidermidis with different ica and aap genetic status, and to evaluate the effect of antibiotic-modified prostheses on bacterial colonization. METHODS: Biofilm formation was determined using fluorescence microscopy imaging. Quantitative analysis was conducted using the biofilm coverage ratio (BCR) calculations. RESULTS: Our investigations prove that the BCR method with fluorescent dye enabled an accurate assessment of biofilm coverage and comparison of the obtained results. The ica+ aap+ strains formed a biofilm on all of the examined vascular prostheses. Uni-Graft(®) modified with covalently immobilized amikacin was effective in preventing bacterial adherence. CONCLUSIONS: Molecular biology techniques combined with phenotype studies give a broad insight into biofilm formation mechanisms. On the other hand, fluorescence microscopy imaging along with BCR calculations are reliable and simple tools to quantitatively estimate biofilm formation, as well as the effectiveness of antimicrobial prosthesis modification.


Assuntos
Proteínas de Bactérias/genética , Biofilmes , Prótese Vascular/microbiologia , Materiais Revestidos Biocompatíveis , Staphylococcus epidermidis/crescimento & desenvolvimento , Staphylococcus epidermidis/genética , Amicacina/farmacologia , Antibacterianos/farmacologia , Aderência Bacteriana , Biofilmes/efeitos dos fármacos , Genótipo , Microscopia de Fluorescência , Óperon , Fenótipo , Desenho de Prótese , Staphylococcus epidermidis/efeitos dos fármacos , Fatores de Tempo
17.
FEMS Microbiol Lett ; 310(2): 97-103, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20722741

RESUMO

The collection of 146 Staphylococcus epidermidis strains isolated from the nasopharynx of lung cancer patients has been studied for the ability of slime secretion and biofilm formation using the Congo red agar (CRA) test and the microtiter plate (MtP) method, respectively. The prevalence of the icaAD and the aap genes was also analyzed. Some isolates (35.6%) were biofilm positive by the MtP method, while 58.9% of isolates exhibited a slime-positive phenotype by the CRA test. The sensitivities of the CRA test evaluated using the MtP method as a gold standard of biofilm production were 73.1%, 97.3% and 13.3% for all the strains screened, ica-positive and ica-negative strains, respectively. The genotype ica(+)aap(+) was correlated with a strong biofilm-producer phenotype. Interestingly, some of the ica(-)aap(-) isolates could also form a biofilm. The correlation between the presence of icaAD genes and the biofilm-positive phenotype by the MtP method as well as slime production by the CRA test was statistically significant (P<0.0001). However, some S. epidermidis strains possess the potential ability of ica-independent biofilm formation; thus, further studies are needed to determine reliable, short-time criteria for an in vitro assessment of biofilm production by staphylococci.


Assuntos
Técnicas Bacteriológicas/métodos , Biofilmes/crescimento & desenvolvimento , Fenótipo , Staphylococcus epidermidis/crescimento & desenvolvimento , Staphylococcus epidermidis/genética , Amidoidrolases/genética , Amidoidrolases/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Genótipo , Humanos , Nasofaringe/microbiologia , Reação em Cadeia da Polimerase
18.
J Cyst Fibros ; 8(3): 186-92, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19250885

RESUMO

BACKGROUND: Respiratory pathogens from CF patients can contaminate inpatient settings, which may be associated with increased risk of patient-to-patient transmission. Few data are available that assess the rate of bacterial contamination of outpatient settings. We determined the frequency of contamination of CF clinics and the effectiveness of alcohol-based disinfectants in reducing hand carriage of bacterial pathogens. METHODS: We conducted a point prevalence survey and before-after trial in outpatient clinics at 7 CF centers. The study examined CF patients with positive respiratory cultures for Pseudomonas, Staphylococcus, Stenotrophomonas or Burkholderia species. Hand carriage and environmental contamination with respiratory pathogens were assessed during clinic visits (Part I) and the effectiveness of hand hygiene performed by CF patients (Part II) was determined using molecular typing of recovered isolates. RESULTS: In Part I (n=97), the contamination rate was 13.6%. Pseudomonas and S. aureus, including methicillin-resistant strains, were cultured from patients' hands (7%), the exam room air (8%), and less commonly, environmental surfaces (1%). In Part II (n=100), the hand carriage rate of pathogens was 13.5% and 4 participants without initial detection of pathogens had hand contamination when recultured at the end of the clinic visit. CONCLUSIONS: Respiratory pathogens from CF patients can contaminate their hands and the clinic environment, but the actual risk of patient-to-patient transmission in the outpatient setting remains difficult to quantify. These findings support several recommendations CF infection control recommendations including hand hygiene for staff and patients, contact precautions for certain pathogens, and disinfecting equipment and surfaces touched by patients and staff.


Assuntos
Instituições de Assistência Ambulatorial/estatística & dados numéricos , Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Infecção Hospitalar/epidemiologia , Fibrose Cística/microbiologia , Contaminação de Equipamentos/estatística & dados numéricos , Transmissão de Doença Infecciosa do Profissional para o Paciente/estatística & dados numéricos , Microbiologia do Ar , Álcoois/uso terapêutico , Burkholderia/isolamento & purificação , Portador Sadio/prevenção & controle , Contagem de Colônia Microbiana , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/transmissão , Estudos Transversais , Contaminação de Equipamentos/prevenção & controle , Mãos/microbiologia , Desinfecção das Mãos/métodos , Humanos , Transmissão de Doença Infecciosa do Profissional para o Paciente/prevenção & controle , New England/epidemiologia , Pseudomonas/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Stenotrophomonas/isolamento & purificação
19.
Biochem J ; 370(Pt 2): 661-9, 2003 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-12443531

RESUMO

From the fruitfly, Drosophila melanogaster, ten members of the cluster of Delta-class glutathione S-transferases (GSTs; formerly denoted as Class I GSTs) and one member of the Epsilon-class cluster (formerly GST-3) have been cloned, expressed in Escherichia coli, and their catalytic properties have been determined. In addition, nine more members of the Epsilon cluster have been identified through bioinformatic analysis but not further characterized. Of the 11 expressed enzymes, seven accepted the lipid peroxidation product 4-hydroxynonenal as substrate, and nine were active in glutathione conjugation of 1-chloro-2,4-dinitrobenzene. Since the enzymically active proteins included the gene products of DmGSTD3 and DmGSTD7 which were previously deemed to be pseudogenes, we investigated them further and determined that both genes are transcribed in Drosophila. Thus our present results indicate that DmGSTD3 and DmGSTD7 are probably functional genes. The existence and multiplicity of insect GSTs capable of conjugating 4-hydroxynonenal, in some cases with catalytic efficiencies approaching those of mammalian GSTs highly specialized for this function, indicates that metabolism of products of lipid peroxidation is a highly conserved biochemical pathway with probable detoxification as well as regulatory functions.


Assuntos
Drosophila melanogaster/enzimologia , Glutationa Transferase/genética , Sequência de Aminoácidos , Animais , Clonagem Molecular , Sequência Conservada , Proteínas de Drosophila , Glutationa Transferase/biossíntese , Glutationa Transferase/química , Dados de Sequência Molecular , Família Multigênica , Filogenia
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