Antimycobacterial and cytotoxicity activities of free and liposome-encapsulated 3-(4'-bromo[1,1'-biphenyl-4-yl)-3-(4-bromo-phenyl)-N,N-dimethyl-2-propen-1-amine

The antimycobacterial activity of 3-(4'-bromo[1,1'-biphenyl-4-yl)-3-(4-bromo-phenyl)-N,N-dimethyl-2-propen-1-amine (BBAP), free or incorporated in preformed liposomes, on extracellular M. tuberculosis H37Rv was 8 and 25 μM (MIC), respectively. Extracellular antimycobacterial activity was not significantly improved by entrapment of BBAP in liposomes, but there was a 6.1-fold reduction of BBAP cytotoxicity on J774 macrophages. Liposomal BBAP or its free form showed IC50 values of 165 and 27 μM, resulting in a selectivity index (SI=IC50/MIC) of 3.4 and 6.6, respectively. Free BBAP in concentrations from 10 to 80 μM were quite effective in eliminating intracellular M. tuberculosis while liposomal formulation was less effective at these concentrations.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Antimycobacterial and cytotoxicity activities of free and liposome-encapsulated 3-(4'-bromo[1,1'-biphenyl-4-yl)-3-(4-bromo-phenyl)-N,N-dimethyl-2-propen-1-amine

The antimycobacterial activity of 3-(4'-bromo[1,1'-biphenyl-4-yl)-3-(4-bromo-phenyl)-N,N-dimethyl-2-propen-1-amine (BBAP), free or incorporated in preformed liposomes, on extracellular M. tuberculosis H37Rv was 8 and 25 μM (MIC), respectively. Extracellular antimycobacterial activity was not significantly improved by entrapment of BBAP in liposomes, but there was a 6.1-fold reduction of BBAP cytotoxicity on J774 macrophages. Liposomal BBAP or its free form showed IC50 values of 165 and 27 μM, resulting in a selectivity index (SI=IC50/MIC) of 3.4 and 6.6, respectively. Free BBAP in concentrations from 10 to 80 μM were quite effective in eliminating intracellular M. tuberculosis while liposomal formulation was less effective at these concentrations334871874CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQSem informaçã

Antimycobacterial and cytotoxicity activities of free and liposome-encapsulated 3-(4'-bromo[1,1'-biphenyl-4-yl)-3-(4-bromo-phenyl)-N,N-dimethyl-2-propen-1-amine

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The antimycobacterial activity of 3-(4'-bromo[1,1'-biphenyl-4-yl)-3-(4-bromo-phenyl)-N,N-dimethyl-2-propen-1-amine (BBAP), free or incorporated in preformed liposomes, on extracellular M. tuberculosis H37Rv was 8 and 25 μM (MIC), respectively. Extracellular antimycobacterial activity was not significantly improved by entrapment of BBAP in liposomes, but there was a 6.1-fold reduction of BBAP cytotoxicity on J774 macrophages. Liposomal BBAP or its free form showed IC50 values of 165 and 27 μM, resulting in a selectivity index (SI=IC50/MIC) of 3.4 and 6.6, respectively. Free BBAP in concentrations from 10 to 80 μM were quite effective in eliminating intracellular M. tuberculosis while liposomal formulation was less effective at these concentrations.334871874Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CNPq_Brasi

Discriminação morfométrica entre Trinomys albispinus (Is. Geoffroy, 1838) e Trinomys minor (Reis & Pessôa, 1995) da Chapada Diamantina, Bahia, Brasil, e o carioótipo de Trinomys albispinus (Rodentia, Echimyidae)

A morphometric discrimination analysis was performed for Trinomys minor (Reis Pessôa, 1995) and Trinomys albispinus (Is. Geoffroy, 1838). The samples used in this study are from localities in the Chapada Diamantina, a vast plateau in central Bahia State, Brazil. A specimen recently obtained near the type-locality of Trinomys minor was allocated to T. albispinus by principal component and discriminant analyses and by qualitative pelage traits. The karyotype of Trinomys albispinus is described on the basis of this specimen as 2n=60, NA=116, with two Nucleolar Organizer Regions (NORs) located in the interstitial region of the long arm of chromosome pair 10. The similarity between this karyotype and that previously published for T. minor is interpreted here as evidence that T. minor and T. albispinus are closely related forms, probably at subspecific level. A pattern of karyological similarity is here documented for other species pairs in the genus in which a close relationship has been revealed by mitochondrial DNA data.Uma análise de discriminação morfométrica foi realizada entre Trinomys albispinus (Is. Geoffroy, 1838) e Trinomys minor (Reis Pessôa, 1995) com base em amostras provenientes da Chapada Diamantina, um vasto platô situado na área central da Bahia. Um espécime recentemente obtido próximo à localidade-tipo de T. minor foi alocado em análises morfométricas multivariadas e em comparações da pelagem à T. albispinus. O cariótipo de Trinomys albispinus é descrito com base neste espécime. Trinomys albispinus apresentou 2n= 60 e NA= 116, e duas regiões organizadoras de nucléolo (RONs) localizadas na região intersticial do braço longo do par cromossômico 10. A similaridade cromossômica entre esse cariótipo e o previamente publicado para T. minor é interpretada aqui como evidência que T. minor e T. albispinus são espécies muito relacionadas, provavelmente em nível subespecífico. Um padrão de similaridade cariotípica é aqui documentado entre outros pares de espécies no gênero onde uma relação filogenética próxima tenha sido revelada por análises de DNA mitocondrial

Schinopsis brasiliensis engl. to combat the biofilm-dependents diseases in vitro

Dental caries and periodontal disease are the most prevalent of the biofilm-dependent diseases. With numerous side effects on the use of chlorhexidine, the search for new safe therapeutic alternatives for microorganisms involved with these diseases increases every day. This study aimed to evaluate the antimicrobial activity and cytotoxicity of extracts made from the bark of Schinopsis brasiliensis Engl. against five oral microorganisms and analyze their phytochemical and thermal degradation profile. The liquid-liquid partition was performed with hexane, chloroform and ethyl acetate. The identification and quantification of the chemical marker was done. Antimicrobial activity was evaluated based on the minimum inhibitory concentration. The cytotoxicity was analyzed based on the hemolysing potential of the samples. The thermal degradation profile was performed by two different methods. Gallic acid was identified as the main compound of the samples and showed the highest amount in the chloroform fraction. All samples were able to inhibit the growth of the microorganisms tested and showed no cytotoxicity. The ethanol extract absorbs less heat than the fractions. All samples exhibited exothermic peak consistent with degradation of gallic acid. Based on the results, the samples used are potential candidates for use in dental formulations for biofilm control924CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQSem informaçã

Synthetic thiosemicarbazones as a new class of Mycobacterium tuberculosis protein tyrosine phosphatase A inhibitors.

Abstract Mycobacterium tuberculosis secretes two protein tyrosine phosphatases as virulence factors, PtpA and PtpB. Inhibition studies of these enzymes have shown significant attenuation of the M. tuberculosis growth in vivo. As PtpA mediates many effects on the regulation of host signaling ensuring the intracellular survival of the bacterium we report, for the first time, thiosemicarbazones as potential novel class of PtpA inhibitors. Several compounds were synthesized and biologically evaluated, revealing interesting results. Enzyme kinetic assays showed that compounds 5, 9 and 18 are non-competitive inhibitors of PtpA, with Ki values ranging from 1.2 to 5.6 µM. Modeling studies clarified the structure-activity relationships observed in vitro and indicated a possible allosteric binding site in PtpA structure. To the best of our knowledge, this is the first disclosure of potent non-competitive inhibitors of PtpA with great potential for future studies and development of analogues

Cytotoxic T cells and mycobacteria

How the immune system kills Mycobacterium tuberculosis is still a puzzle. the classical picture of killing due to phagocytosis by activated macrophages may be only partly correct. Based on recent evidence, we express here the view that cytotoxic T lymphocytes also make an important contribution and suggest that DNA vaccines might be a good way to enhance this. (C) 2001 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.Univ São Paulo, Sch Med Ribeirao Preto, Dept Biochem & Immunol, BR-14049900 Ribeirao Preto, SP, BrazilUniv São Paulo, Sch Pharmaceut Sci Ribeirao Preto, Dept Clin Anal Bromatol & Toxicol, BR-14049 Ribeirao Preto, SP, BrazilUniversidade Federal de São Paulo, Dept Microbiol & Immunol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol & Immunol, São Paulo, BrazilWeb of Scienc