ABSTRACT
Trichophyton rubrum is a dermatophyte, which can cause infections in human skin, hair and nail. Pothomorphe umbellata (L.) Miq. (Piperaceae) is a native Brazilian plant, in which phytochemical studies have demonstrated the presence of steroids, 4-nerolidylcatechol, sesquiterpenes and essential oils. The objective of this study was to analyze the in vitro activity of extracts and fractions of P. umbellata on resistant strains of T. rubrum. The microdilution plate method was utilized to test Tr1, H6 and ΔTruMDR2 strains of T. rubrum; ΔTruMDR2 strain was obtained from H6 by TruMDR2 gene rupture, which is involved in multiple drugs resistance. The highest antifungal activity to all strains was observed for dichloromethane and hexane fractions of the 70% ethanolic extract which showed minimal inhibitory concentration (MIC) and minimal fungicide concentration (MFC) of 78.13 µg/mL. This antifungal activity was also obtained by 70% ethanolic extract, which presented MIC and MFC of 78.13 µg/mL to ΔTruMDR2, whereas the MIC values for Tr1 and H6 were 78.13 and 156.25 µg/mL, respectively. Our results suggest the potential for future development of new antifungal drugs from P. umbellata, especially to strains presenting multiple resistance.
Subject(s)
Antifungal Agents/pharmacology , Piperaceae/chemistry , Plant Extracts/pharmacology , Trichophyton/drug effects , Antifungal Agents/isolation & purification , Brazil , Colony Count, Microbial , Drug Evaluation, Preclinical , Drug Resistance, Multiple, Fungal/genetics , Ethanol , Gas Chromatography-Mass Spectrometry , Gene Deletion , Genes, Fungal , Hexanes , Methylene Chloride , Microbial Sensitivity Tests , Plant Extracts/isolation & purification , Solvents , Trichophyton/geneticsABSTRACT
The present study aimed to analyze the genetic similarity between genomic profiles of thirteen Klebsiella oxytoca and seven Klebsiella pneumoniae samples isolated from two different collections carried out in different places of dental offices. Random amplified polymorphic DNA (RAPD) technique and similarity coefficients (calculated by Sorensen-Dice and simple matching) were applied to determine their genetic profile of randomic DNA sequences. The majority of the isolates of K. pneumoniae and K. oxytoca presented similar coefficient values (¡Ý 0.80). Thus, it was possible to identify that strain dissemination occurred mainly via the hands of the surgeon-dentists and, finally, to determine the genetic similarity of the strains from dental office environments.(AU)
Subject(s)
Animals , Klebsiella oxytoca , Genetic Profile , Klebsiella pneumoniae , Dental OfficesABSTRACT
O emprego de animais de laboratório em conjunto com estudos realizados em humanos fornece uma base para a compreensão de vários processos fisiológicos e patológicos importantes. Além disso, os resultados de estudos experimentais possibilitam uma melhor compreensão e segurança para o desenvolvimento de técnicas cirúrgicas na clínica médica. Por se tratar de material biológico vivo, devemos garantir sua integridade física levando-se em consideração as contaminações microbiológicas, a genética, a nutrição ea correta manipulação, a fim de se evitar que ocorram conclusões inválidas nos experimentos ou que se aumente desnecessariamente o número de animais utilizados. Em paralelo às preocupações e legislações sobre o uso de animais de laboratório, desenvolveu-se também a preocupação com o bem estar e a segurança das pessoas que manuseiam os animais de laboratório, uma vez que estas correm riscos de adquirirem doenças ocupacionais pela presença de contaminações zoonóticas ou por desenvolvimento de alergias. A prevenção requer a aplicação de modernos avanços tecnológicos no desenho do biotério e nas rotinas de trabalho. Infelizmente poucos estabelecimentos do país apresentam recursos humanos com formação apropriada e infra-estrutura básica de pesquisa que inclua os centros de criação de animais de laboratório, equivalentes àqueles existentes nos Estados Unidos e Europa.
Subject(s)
Humans , /legislation & jurisprudence , /prevention & control , Laboratory Personnel/ethics , Laboratory Personnel/legislation & jurisprudence , Animals, LaboratoryABSTRACT
O presente estudo teve por objetivo avaliar a classe de metabólitos secundários responsável pela atividade antioxidante e antimicrobiana de extratos da casca de Stryphnodendron adstringens (Mart.) Coville(Leguminosae-Mimosoidae), planta amplamente utilizada medicinalmente pela população. Foram obtidos extratos da casca utilizando etanol 50%, etanol 70%, acetona:água (7:3, v/v) e clorofórmio. A bioprospecção da atividade antioxidante foi realizada por meio de cromatografia em camada delgada revelada com 2,2-difenil-1-picrilhidrazila (DPPH) e a capacidade de sequestro de radicais livres utilizando DPPH foi quantificada por espectrofotometria. A bioprospecção da atividade antibacteriana foi realizada por meio de difusão em ágar e bioautografia. A cromatografia revelada com DPPH revelou atividade antioxidante na região onde foram identificadas as manchas referentes aos derivados de taninos e o extrato clorofórmico foi o que apresentou menor capacidade de sequestro de radicais livres. A atividade antimicrobiana foi comprovada para os extratos polares pela formação de halos de inibição de crescimento bacteriano e abioautografia revelou atividade na região onde foram identificadas as manchas de derivados tânicos. Assim, foi determinado que extratos da casca de S. adstringens apresentaram atividades antioxidante e antimicrobiana devido aos metabólitos secundários derivados da classe de taninos, que são os principais constituintes desta droga vegetal, de acordo com a literatura.
Subject(s)
Antioxidants , Fabaceae , Phytotherapy , TanninsABSTRACT
The aim of this research was to evaluate the susceptibility profile of Pseudomonas spp. and the prevalence of bacterial samples isolated from horizontal surfaces surrounding wash-basins used by dentists in several adjoined consulting-rooms, at points next to and at a distance from the basin, before and after surgical procedures. Our results showed a high percentage of Gram-positive cocci and Gram-negative bacilli; 34.66% were Staphylococcus spp. and 30.12% were non-fermentative Gram-negative bacilli among which Pseudomonas spp. (40.90%) was the commonest genus. Analysis of the susceptibility profile of Pseudomonas spp. isolates by determining the minimal inhibitory concentration (MIC) of 14 antibiotics showed a great variation among the strains and high rates of resistance to cefazolin, ceftazidime and aztreonan. Of the 14 antibiotics tested, 59.03% were found to be active against all the environmental isolates. Strains were resistant to aztreonan (62.82%), while susceptibility to third generation cephalosporins was variable
Subject(s)
Gram-Negative Bacteria , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria , Gram-Positive Bacteria/isolation & purification , Dental Offices , Pseudomonas Infections/epidemiology , Pseudomonas aeruginosaABSTRACT
Crude extracts and fractions from aerial parts of Physalis angulata have been bioassayed for antimycobacterial activity. Fraction A1-29-12 containing physalins B, F and D exhibited a minimum inhibitory concentration value (MIC) against Mycobacterium tuberculosis H(37)Rv strain of 32 microg/mL. Purified physalin B and physalin D were also tested showing MIC values against Mycobacterium tuberculosis H(37)Rv strain of > 128 microg/mL and 32 microg/mL respectively, suggesting that physalin D plays a relevant role in the antimycobacterial activity displayed. Structural elucidation of both physalins D and B was based on detailed (13)C and (1)H NMR spectral analysis with the aid of 2D-correlation spectroscopy ((1)H-(1)H, COSY, HSQC and HMBC). The assignment of the (13)C chemical shift for physalin D is reported here for the first time.