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1.
Braz. j. biol ; 82: e236297, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1153472

RESUMO

Abstract Plectranthus barbatus Andrews (Lamiaceae) is widely distributed in the world and has a range of popular therapeutic indications. This work aimed to evaluate the phytochemical characterization of two leaf extracts of P. barbatus, and their antimicrobial, antineoplastic and immunomodulatory potential. After collection, herborization and obtainment of the P. barbatus aqueous extract (PBA) and acetone:water 7:3 P. barbatus organic extract (PBO), the phytochemical characterization was performed by high-performance liquid chromatography (HPLC). The antimicrobial activity was performed to determine the minimum inhibitory concentration (MIC) against eight bacterial strains using the microdilution test and the fungus Trichophyton rubrum by disc diffusion assay and microdilution test. Cytotoxicity was assessed by MTT and trypan blue methods in normal peripheral blood mononuclear cells (PBMCs) at concentrations ranged between 0.1 to 100 µg.mL-1 and in neoplastic cell lines Toledo, K562, DU-145 and PANC-1 at 1, 10 and 100 µg.mL-1 . Immunomodulatory activity, was evaluated by sandwich ELISA of proinflammatory cytokines at BALB/c mice splenocytes cultures supernatant. Both extracts presented flavonoids, cinnamic derivatives, steroids and ellagic acid. PBO showed bacteriostatic activity against Acinetobacter baumannii (MIC = 250 µg.mL-1) clinical isolate and PBA fungistatic activity against Trichophyton rubrum (MIC = 800 µg.mL-1). The extracts did not exhibit toxicity to PBMCs and neoplastic cells (IC50 > 100 µg.mL-1). Additionally, PBO at 100 µg.mL-1 significantly inhibited IFN-γ and IL-17A cytokines (p = 0.03). Plectranthus barbatus is a potential candidate for therapeutic use due to its low toxicity in healthy human cells and exhibits biological activities of medical interest as bacteriostatic, fungistatic and immunomodulatory.


Resumo Plectranthus barbatus Andrews (Lamiaceae) é amplamente distribuída no mundo e com uma série de indicações terapêuticas populares. Este trabalho teve como objetivo avaliar a caracterização fitoquímica de dois extratos da folha de P. barbatus e seu potencial antimicrobiano, antineoplásico e imunomodulador. Após coleta, herborização e obtenção do extrato aquoso (PBA) e acetona: água 7: 3 (orgânico) (PBO) de P. barbatus, a caracterização fitoquímica foi realizada por cromatografia líquida de alta eficiência (CLAE). A atividade antimicrobiana foi realizada para determinar a concentração inibitória mínima (CIM) contra oito cepas bacterianas usando o teste de microdiluição e o fungo Trichophyton rubrum por ensaio de difusão em disco e teste de microdiluição. A citotoxicidade foi avaliada por métodos MTT e azul de tripan em células normais mononucleares do sangue periférico (CMSP) em concentrações variadas entre 0,1 a 100 µg.mL-1 e nas linhagens celulares neoplásicas Toledo, K562, DU-145 e PANC-1 em 1, 10 e 100 µg.mL-1 . A atividade imunomoduladora foi avaliada por ELISA sanduíche de citocinas pró-inflamatórias em sobrenadante de culturas de esplenócitos de camundongos BALB/c. Ambos os extratos apresentaram flavonoides, derivados cinâmicos, esteróides e ácido elágico. O PBO mostrou atividade bacteriostática contra Acinetobacter baumannii (CIM = 250 µg.mL-1) e atividade fungistática do PBA contra Trichophyton rubrum (CIM = 800 µg.mL-1). Os extratos não apresentaram toxicidade para CMSP e células neoplásicas (IC50 > 100 µg.mL-1). Além disso, o PBO a 100 µg.mL-1 inibiu significativamente as citocinas IFN-γ e IL-17A (p = 0,03). Plectranthus barbatus é um candidato potencial para uso terapêutico devido à sua baixa toxicidade em células humanas saudáveis ​​e exibe atividade de interesse médico como bacteriostática, fungistática e imunomoduladora.

2.
Braz J Biol ; 82: e236297, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33787716

RESUMO

Plectranthus barbatus Andrews (Lamiaceae) is widely distributed in the world and has a range of popular therapeutic indications. This work aimed to evaluate the phytochemical characterization of two leaf extracts of P. barbatus, and their antimicrobial, antineoplastic and immunomodulatory potential. After collection, herborization and obtainment of the P. barbatus aqueous extract (PBA) and acetone:water 7:3 P. barbatus organic extract (PBO), the phytochemical characterization was performed by high-performance liquid chromatography (HPLC). The antimicrobial activity was performed to determine the minimum inhibitory concentration (MIC) against eight bacterial strains using the microdilution test and the fungus Trichophyton rubrum by disc diffusion assay and microdilution test. Cytotoxicity was assessed by MTT and trypan blue methods in normal peripheral blood mononuclear cells (PBMCs) at concentrations ranged between 0.1 to 100 µg.mL-1 and in neoplastic cell lines Toledo, K562, DU-145 and PANC-1 at 1, 10 and 100 µg.mL-1 . Immunomodulatory activity, was evaluated by sandwich ELISA of proinflammatory cytokines at BALB/c mice splenocytes cultures supernatant. Both extracts presented flavonoids, cinnamic derivatives, steroids and ellagic acid. PBO showed bacteriostatic activity against Acinetobacter baumannii (MIC = 250 µg.mL-1) clinical isolate and PBA fungistatic activity against Trichophyton rubrum (MIC = 800 µg.mL-1). The extracts did not exhibit toxicity to PBMCs and neoplastic cells (IC50 > 100 µg.mL-1). Additionally, PBO at 100 µg.mL-1 significantly inhibited IFN-γ and IL-17A cytokines (p = 0.03). Plectranthus barbatus is a potential candidate for therapeutic use due to its low toxicity in healthy human cells and exhibits biological activities of medical interest as bacteriostatic, fungistatic and immunomodulatory.


Assuntos
Plectranthus , Animais , Arthrodermataceae , Leucócitos Mononucleares , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia
3.
J Appl Microbiol ; 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32767796

RESUMO

AIM: The aim of the present study was to examine the vaccine immune response in ewes supplemented with Bacillus toyonensis BCT-7112T during a period of 5-day supplementation before vaccination against a recombinant Clostridium perfringens epsilon toxin (rETX). METHODS AND RESULTS: Ewes were vaccinated with 200 µg of rETX adjuvanted with 10% aluminium hydroxide. The treat group was orally supplemented with B. toyonensis BCT-7112T (3 × 108 viable spores) for 5 days prior to the first and second vaccination. Ewes supplemented with B. toyonensis BCT-7112T showed higher neutralizing antibody titres than the non-supplemented ewes (P < 0·05), with an increase in serum levels for total IgG anti-rETX by 3·2-fold (P < 0·0001), and for both IgG isotypes IgG1 and IgG2 by 2·1-fold and 2·3-fold (P < 0·01), respectively, compared with the control group. The peripheral blood mononuclear cells of ewes in the supplemented group had a higher (P < 0·05) cytokine mRNA transcription levels for IL-2 (6·4-fold increase), IFN-γ (2·9-fold increase) and transcription factor Bcl6 (2·3-fold increase) compared with the control group. CONCLUSION: We conclude that a 5 days of supplementation with B. toyonensis BCT-7112T prior vaccination is sufficient to significantly improve the humoral immune response of ewes against C. perfringens recombinant ETX vaccine. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings open a new perspective in the utilization of B. toyonensis BCT-7112T as an immunomodulator since a 5 days period of probiotic supplementation is sufficient to improve the vaccine immune response.

4.
Arq. bras. med. vet. zootec. (Online) ; 70(6): 1807-1813, nov.-dez. 2018. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-970491

RESUMO

This study determined the distribution of stx1 and stx2 genes in Escherichia coli isolated from dairy herds with regard to animal age, season, and farm production-scale, and analyzed the phylogenetic distribution of the groups A, B1, B2, and D of 276 isolates of bovine feces Shiga toxin-producing E. coli (STEC). The stx1 profile was the most common, detected in 20.4% (202/990) of the isolates, followed by stx2 (4.54%, 45/990) and stx1+stx2 (2.92%, 29/990). The stx1 gene was detected more frequently in calves than in adult animals. In the dry season (winter), the presence of stx1+stx2 profile in cattle feces was higher than in the rainy season (summer), while no significant changes were observed between seasons for the stx1 and stx2 profiles. The most predominant phylogenetic groups in adult animals were B1, A, and D, while groups A and B1 prevailed in calves. Our data highlight the importance of identifying STEC reservoirs, since 7.5% of the tested isolates were positive for stx2, the main profile responsible for the hemolytic-uremic syndrome (HUS). Moreover, these microorganisms are adapted to survive even in hostile environments and can contaminate the food production chain, posing a significant risk to consumers of animal products.(AU)


Esse estudo determinou a distribuição dos genes stx1 e stx2 em Escherichia coli isolados de rebanhos leiteiros em relação a idade, estação e produção, e analisaram a distribuição filogenética dos grupos A, B1, B2 e D de 276 E. coli produtoras de toxina Shiga (STEC). O perfil stx1 foi mais comum, detectado em 20,4% (202/990) dos isolados, seguido de stx2 (4,54%, 45/990) e stx1+stx2 (2,92%, 29/990). O gene stx1 foi detectado mais frequentemente em bezerros que animais adultos. No período de seca (inverno), a presença do perfil stx1+stx2 nas fezes dos bovinos foi mais prevalente que no período chuvoso (verão), apesar de não haver diferença significativa entre estações para os perfis stx1 e stx2. Os grupos filogenéticos mais predominantes em animais adultos foram B1, A e D, enquanto grupos A e B2 prevaleceram em bezerros. Nossos dados enfatizam a importância de se detectar reservatórios de STEC já que 7,5% dos isolados testados foram positivos para stx2, o perfil mais prevalente em casos de síndrome hemolítica-urêmica. Ademais, esses microorganismos são adaptados à sobreviver em ambientes hostis e contaminam a cadeia alimentar, levando a risco significativo para consumidores de alimentos de origem animal.(AU)


Assuntos
Animais , Bovinos , Bovinos/genética , Toxina Shiga I/genética , Toxina Shiga II/genética , Escherichia coli/isolamento & purificação , Escherichia coli/genética
5.
Arq. bras. med. vet. zootec. (Online) ; 69(5): 1351-1356, set.-out. 2017. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-879374

RESUMO

The strangles is an infectious disease that affects horses from all ages and causes important economic losses in the equine-related business. The aim of this work was to evaluate the immunogenicity of the recombinant M protein from Streptococcus equi (rSeM) co-administered with the recombinant heat-labile enterotoxin B subunit from Escherichia coli (rLTB) in mice and horses. A total of 72 female Balb-c mice were divided into eight groups and 18 horses were divided into six groups. The animals were inoculated by intramuscular (IM) or intranasal (IN) routes with different treatments of rSeM, rLTB and/or Al(OH)3. The results obtained in both species, independent of administration routes, demonstrated that rSeM + rLTB had higher levels of specific serum immunoglobulins, however, in mucosal immunity the increase was not identified. Thus, the use of rSeM as vaccine antigen and rLTB as adjuvant can be a potential tool in the control of equine strangles.(AU)


Assuntos
Animais , Camundongos , Enterotoxinas/administração & dosagem , Cavalos/imunologia , Streptococcus equi , Proteínas da Matriz Viral
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