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1.
Plants (Basel) ; 11(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36079594

RESUMO

Foeniculum vulgare is used for the treatment of diarrhea in Mexican traditional medicine. Hexane extract showed 94 % inhibition of Giardia duodenalis trophozoites at 300 µg/mL. Therefore, 20 constituents of hexane extract were evaluated to determine their antigiardial activity. Interestingly, six compounds showed good activity toward the parasite. These compounds were (1R,4S) (+)-Camphene (61%), (R)(-)-Carvone (66%), estragole (49%), p-anisaldehyde (67%), 1,3-benzenediol (56%), and trans, trans-2,4-undecadienal (97%). The aldehyde trans, trans-2,4-undecadienal was the most active compound with an IC50 value of 72.11 µg/mL against G. duodenalis trophozoites. This aldehyde was less toxic (IC50 588.8 µg/mL) than positive control metronidazole (IC50 83.5 µg/mL) against Vero cells. The above results could support the use of F. vulgare in Mexican traditional medicine.

2.
Biomed Res Int ; 2014: 714173, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24982905

RESUMO

Commercial culture media present interlot variations in biological activity. We have previously designed a homemade and economic culture medium, PEHPS medium, for the axenic cultivation of Entamoeba histolytica and Trichomonas vaginalis. Trophozoites of amoebae and trichomonads grow well in this medium. Furthermore, the medium is stable for several months when stored frozen or refrigerated. The objective of this work was to modify PEHPS medium to support the in vitro growth of Giardia lamblia. Inocula of 5 × 10(3) trophozoites/mL of G. lamblia were incubated at 36.5°C in modified PEHPS or TYI-S-33 medium. Then, the growths of the three Giardia strains in both media were compared. The logarithmic growth phase lasted 72 h; the mean yield of the strains ranged from 10.06 to 11.43 × 10(5) Giardia trophozoites/mL, and the range of duplication time in the three strains was from 5.67 to 6.06 in modified PEHPS medium. These growth characteristics were not significantly different from those obtained with TYI-S-33 medium. We conclude that modified PEHPS medium might be used for the axenic cultivation of G. lamblia.


Assuntos
Técnicas de Cultura de Células/métodos , Meios de Cultura/farmacologia , Giardia lamblia/crescimento & desenvolvimento , Animais , Bovinos , Giardia lamblia/efeitos dos fármacos , Fatores de Tempo , Trofozoítos/efeitos dos fármacos , Trofozoítos/crescimento & desenvolvimento
3.
Acta Parasitol ; 58(4): 519-26, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24338313

RESUMO

Sexually transmitted diseases are a major cause of acute disease worldwide, and trichomoniasis is the most common and curable disease, generating more than 170 million cases annually worldwide. Trichomonas vaginalis is the causal agent of trichomoniasis and has the ability to destroy in vitro cell monolayers of the vaginal mucosa, where the phospholipases A2 (PLA2) have been reported as potential virulence factors. These enzymes have been partially characterized from the subcellular fraction S30 of pathogenic T. vaginalis strains. The main objective of this study was to purify a phospholipase A2 from T. vaginalis, make a partial characterization, obtain a partial amino acid sequence, and determine its enzymatic participation as hemolytic factor causing lysis of erythrocytes. Trichomonas S30, RF30 and UFF30 sub-fractions from GT-15 strain have the capacity to hydrolyze [2-(14)C-PA]-PC at pH 6.0. Proteins from the UFF30 sub-fraction were separated by affinity chromatography into two eluted fractions with detectable PLA A2 activity. The EDTA-eluted fraction was analyzed by HPLC using on-line HPLC-tandem mass spectrometry and two protein peaks were observed at 8.2 and 13 kDa. Peptide sequences were identified from the proteins present in the eluted EDTA UFF30 fraction; bioinformatic analysis using Protein Link Global Server charged with T. vaginalis protein database suggests that eluted peptides correspond a putative ubiquitin protein in the 8.2 kDa fraction and a phospholipase preserved in the 13 kDa fraction. The EDTA-eluted fraction hydrolyzed [2-(14)C-PA]-PC lyses erythrocytes from Sprague-Dawley in a time and dose-dependent manner. The acidic hemolytic activity decreased by 84% with the addition of 100 µM of Rosenthal's inhibitor.


Assuntos
Fosfolipases A2/isolamento & purificação , Fosfolipases A2/metabolismo , Trichomonas vaginalis/enzimologia , Sequência de Aminoácidos , Animais , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Eritrócitos/efeitos dos fármacos , Hemólise , Concentração de Íons de Hidrogênio , Peso Molecular , Fosfolipases A2/química , Fosfolipases A2/genética , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Trichomonas vaginalis/genética
4.
Medicina (B Aires) ; 69(3): 318-20, 2009.
Artigo em Espanhol | MEDLINE | ID: mdl-19622479

RESUMO

Amebiasis caused by Entamoeba histolytica is a problem of public world health. The most frequent clinical presentation are the dysentery and the amebic liver abscess. Fifty millions of cases and more than 100.000 deaths for this disease are reported annually worldwide. The life cycle of E. histolytica has two phases: trophozoite and cyst. Trophozoites are the causal agent of disease. The effective treatment for the amebiasis includes drugs with serious collateral effects. Ivermectin is a macrolid with activity against endoparasites and ectoparasites causing strongiloidosis, filariasis, oncocercosis, scabiasis and pediculosis. The use of ivermectin has been extended almost worldwide; it is recognized as a safe drug. The main objective of this study was to determine in vitro sensibility of trophozoites of E. histolytica was to the treatment with ivermectin. To determine the sensibility of the parasites to the drug, E. histolytica was cultivated in PEHPS medium. During its logarithmic growth phase the trophozoites were exposed to different concentrations of ivermectin. As controls other antiparasitic drugs were used. For each drug, serial dilutions were prepared, and mixed in culture tubes with parasites (2 x 104 cells/ml). They were incubated for 72 h and then the percentage of growth inhibition was calculated by Probit analysis. Ivermectin showed activity against trophozoites of E. histolytica. The 50% of growth inhibition of ivermectin was 6.40 mg/ml. This dose was higher than for other anti parasitic drugs. Its activity in vivo in animal models remains to be demonstrated.


Assuntos
Antiprotozoários/farmacologia , Entamoeba histolytica/efeitos dos fármacos , Ivermectina/farmacologia , Trofozoítos/efeitos dos fármacos , Relação Dose-Resposta a Droga , Testes de Sensibilidade Parasitária
5.
Medicina (B.Aires) ; 69(3): 318-320, jun. 2009. tab
Artigo em Espanhol | LILACS | ID: lil-633643

RESUMO

La amibiasis producida por Entamoeba histolytica es un problema de salud pública. Las formas clínicas más frecuentes son la disentería y el absceso hepático amibiano. En el mundo se notifican anualmente 50 millones de casos y más de 100 000 muertes por esta enfermedad. El ciclo de vida de E. histolytica tiene dos fases: trofozoíto y quiste. Los trofozoítos son los responsables de producir enfermedad. El tratamiento actual para la amibiasis incluye medicamentos con efectos colaterales serios. La ivermectina es un macrólido con actividad contra endoparásitos y ectoparásitos causantes de strongiloidosis, filariasis, oncocercosis, sarna y pediculosis. Su uso está extendido a casi todo el mundo y se lo reconoce como un medicamento seguro. El objetivo de este trabajo fue determinar la sensiblidad in vitro de trofozoítos de E. histolytica al tratamiento con ivermectina. Para determinar su sensibilidad a la droga, se utilizaron trofozoítos de E. histolytica cultivados en medio PEHPS. Durante su fase de crecimiento logarítmico se expusieron a diferentes concentraciones de ivermectina. Como controles se usaron otras drogas antiparasitarias. Se prepararon diluciones seriadas de cada droga, luego se agregaron a tubos con parásitos (2 x 10(4) células/ml). Se incubó por 72 h y luego se determinó el porcentaje de inhibición de crecimiento calculado por análisis Probit. La ivermectina tiene actividad contra trofozoítos de E. histolytica. La dosis de ivermectina que produjo el 50% de inhibición de crecimiento fue de 6.40 mg/ml. Esta dosis fue mayor a la encontrada con otras drogas antiparasitarias. Falta demostrar su actividad in vivo en modelos animales.


Amebiasis caused by Entamoeba histolytica is a problem of public world health. The most frequent clinical presentation are the dysentery and the amebic liver abscess. Fifty millions of cases and more than 100.000 deaths for this disease are reported annually worldwide. The life cycle of E. histolytica has two phases: trophozoite and cyst. Trophozoites are the causal agent of disease. The effective treatment for the amebiasis includes drugs with serious collateral effects. Ivermectin is a macrolid with activity against endoparasites and ectoparasites causing strongiloidosis, filariasis, oncocercosis, scabiasis and pediculosis. The use of ivermectin has been extended almost worldwide; it is recognized as a safe drug. The main objective of this study was to determine in vitro sensibility of trophozoites of E. histolytica was to the treatment with ivermectin. To determine the sensibility of the parasites to the drug, E. histolytica was cultivated in PEHPS medium. During its logarithmic growth phase the trophozoites were exposed to different concentrations of ivermectin. As controls other antiparasitic drugs were used. For each drug, serial dilutions were prepared, and mixed in culture tubes with parasites (2 x 10(4) cells/ml). They were incubated for 72 h and then the percentage of growth inhibition was calculated by Probit analysis. Ivermectin showed activity against trophozoites of E. histolytica. The 50% of growth inhibition of ivermectin was 6.40 mg/ml. This dose was higher than for other anti parasitic drugs. Its activity in vivo in animal models remains to be demonstrated.


Assuntos
Antiprotozoários/farmacologia , Entamoeba histolytica/efeitos dos fármacos , Ivermectina/farmacologia , Trofozoítos/efeitos dos fármacos , Relação Dose-Resposta a Droga , Testes de Sensibilidade Parasitária
6.
Rev Salud Publica (Bogota) ; 9(1): 76-85, 2007.
Artigo em Espanhol | MEDLINE | ID: mdl-17502965

RESUMO

OBJECTIVE: Acute respiratory diseases occupy the first 5 places in infantile morbidity and mortality around the world, two million children directly dying from such cause annually. Environmental tobacco smoke (ETS) contains toxic and irritating compounds having an injurious effect on health, producing increased risk of morbidity and mortality in non-smoking adults and children. Our main objective was determining the association between ETS and pneumonia in children. MATERIAL AND METHODS: This was an unmatched case and controls hospital-based study. Odds ratio (OR) and 95% confidence interval (CI) were calculated. RESULTS: A total of 285 patients (142 cases and 143 controls) were studied; 47,4 % of the patients were female and average age was 4,5,+2,7. OR for patients being exposed to ETS developing pneumonia was 3,44 (CI: 2,11-5,6). DISCUSSION: Children being exposed to ETS increases the risk of developing pneumonia by more than threefold.


Assuntos
Pneumonia/epidemiologia , Pneumonia/etiologia , Poluição por Fumaça de Tabaco/efeitos adversos , Estudos de Casos e Controles , Pré-Escolar , Feminino , Humanos , Masculino , México
7.
Rev. salud pública ; 9(1): 76-85, ene.-mar. 2007. tab
Artigo em Espanhol | LILACS | ID: lil-450556

RESUMO

Objetivo Las enfermedades respiratorias agudas ocupan en el mundo los primeros 5 lugares en morbilidad y mortalidad infantil, anualmente mueren más de dos millones de niños por esa causa. El humo del tabaco ambiental (HTA) contiene compuestos irritantes y tóxicos nocivos para la salud, que incrementan el riesgo de morbilidad y mortalidad en lactantes, niños y adultos no fumadores. Nuestro principal objetivo fue determinar la asociación entre HTA y la presencia de neumonías en niños. Material y métodos Se realizó un estudio de casos y controles no pareados. Se calcularon las razones de momios (RM) e intervalo de confianza 95 por ciento (IC) para cada variable. Resultados Se analizaron 285 pacientes, 142 casos y 143 controles, 47,4 por ciento femeninos, la edad promedio fue 4,5+2,7 años. La RM para expuestos al HTA fue 3,44, IC 2,1- 5,6. Discusión La exposición a HTA incrementa más de tres veces el riesgo de padecer neumonías en niños.


Objective Acute respiratory diseases occupy the first 5 places in infantile morbidity and mortality around the world, two million children directly dying from such cause annually. Environmental tobacco smoke (ETS) contains toxic and irritating compounds having an injurious effect on health, producing increased risk of morbidity and mortality in non-smoking adults and children. Our main objective was determining the association between ETS and pneumonia in children. Material and methods This was an unmatched case and controls hospital-based study. Odds ratio (OR) and 95 percent confidence interval (CI) were calculated. Results A total of 285 patients (142 cases and 143 controls) were studied; 47,4 percent of the patients were female and average age was 4,5,+2,7. OR for patients being exposed to ETS developing pneumonia was 3,44 (CI: 2,11-5,6). Discussion Children being exposed to ETS increases the risk of developing pneumonia by more than threefold.


Assuntos
Pré-Escolar , Feminino , Humanos , Masculino , Pneumonia/epidemiologia , Pneumonia/etiologia , Poluição por Fumaça de Tabaco/efeitos adversos , Estudos de Casos e Controles , México
8.
Int J Toxicol ; 25(5): 403-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16940012

RESUMO

The aim of this experimental study was to analyze in vitro effects of clofibric acid on vimentin and desmin contents in rat myocardiocytes, which was carried out in primary myocardiocyte cells that were treated only with clofibric acid at 0.1 mM. The measurement of vimentin and desmin were done by Western blotting and densitometry. This study showed that myocardiocytes exposed to clofibric acid exhibit a 26.3% decrease in vimentin and a 42.1% decrease in desmin. Considering the role that these intermediate filaments play in the anchorage and cellular organization of myocardiocytes, the decrease of desmin and vimentin observed in cells treated with clofibric acid may be partially responsible for the adverse effects observed in patients. In conclusion, the alteration of cytoskeletal proteins may be a cause of cardiopathy in patients treated with these compounds.


Assuntos
Anticolesterolemiantes/farmacologia , Ácido Clofíbrico/farmacologia , Desmina/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Vimentina/metabolismo , Animais , Células Cultivadas , Masculino , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Miócitos Cardíacos/metabolismo , Ratos , Ratos Sprague-Dawley
9.
Med Sci Monit ; 9(6): BR225-30, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12824945

RESUMO

BACKGROUND: Sphingomyelinase enzymes are pathogenic factors of several intracellular bacteria species, which have been little studied in Mycobacterium tuberculosis. MATERIAL/METHODS: Cell free extracts from H37Rv and CDC-1551 M. tuberculosis strains were assayed for sphingomyelinase activity by using [N-methyl-14C]-sphingomyelin as substrate. Double-directional thin-layer chromatography was used to separate the substrate and hydrolysis product. Sphingomyelinase activity was analyzed as a function of incubation time, dose, pH and the presence of MgCl2, CaCl2, ZnSO4, HgCl2, MnCl2, CoCl2 and EDTA (1 or 10 mM). RESULTS: Mycobacterial preparations hydrolyzed [14C]-sphingomyelin, in time- and dose-dependent manners, producing [14C]-phosphorylcholine as a unique product. The activity of H37Rv neutral sphingomyelinase at pH 7.5 was 2.15 times higher than that of CDC-1551. This activity was inhibited 21-82% by Ca2+, Hg2+ or Zn2+ and EDTA, and stimulated 40-117% by Mn2+ and Mg2+. In addition, preparations from both strains showed two peaks of sphingomyelinase, one at pH 5.5 and the other at pH 3.0. However, these activities were 4-22 times lower than that observed at pH 7.5 for strain H37Rv. Preparations from H37Rv, but not those of CDC-1551, hydrolyzed sphingomyelin at pH 8-9, with a specific activity similar to that of the neutral CDC-1551 enzyme. CONCLUSIONS: Both strains H37Rv and CDC-1551 of M. tuberculosis have cation-dependent acidic and neutral sphingomyelinase-C enzymes, showing the neutral as the major activity. In addition, H37Rv has an alkaline sphingomyelinase-C. The importance of SMases in M. tuberculosis pathogenesis remains to be elucidated.


Assuntos
Mycobacterium tuberculosis/enzimologia , Esfingomielina Fosfodiesterase/metabolismo , Proteínas de Bactérias/metabolismo , Sistema Livre de Células , Concentração de Íons de Hidrogênio , Cinética , Mycobacterium tuberculosis/patogenicidade , Concentração Osmolar , Virulência
10.
J Parasitol ; 89(1): 105-12, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12659311

RESUMO

Trichomonad total extracts (TTE), or vesicular (P30) and soluble (530) subcellular fractions from 3 pathogenic Trichomonas vaginalis strains (GT-3. GT-13. and GT-15), lysed both human and Sprague-Dawley rat erythrocytes in a time- and dose-dependent manner. The entire hemolytic activity of TTE was located in P30, showing 2 peaks of maximum activity, one at pH 6.0 and another at pH 8.0. in the presence of 1 mM Ca2+. Hemolytic activity on rat erythrocytes was greater at pH 6.0 16.71 +/- 0.33 hemolytic units IHU]/mg/hr to 11.60 +/- 0.24 HU/mg/hr) than at pH 8.0 (3.81 +/- 0.30 HU/mg/hr to 5.75 +/- 0.65 HU/mg/hr). and it was greater than that on human red blood cells at pH 6.0 (2.67 +/- 0.19 HU/mg/hr to 4.08 +/- 0.15 HU/mg/hr) or pH 8.0 (2.24 +/- 0.0 9 HU/mg/hr to 2.81 +/- 0.06 HU/mg/hr). The alkaline and acidic hemolytic activity diminished (60-93% at pH 6.0 and 78-93% at pH 8.0) by the effect of 80 microM Rosenthal's inhibitor, which also inhibited 27-45% and 29-54% trichomonad alkaline and acidic phospholipase A activities, respectively. Vesicles, vacuoles, and hydrogenosomes were rich in P30. Trichomonas vaginalis has a hemolytic PLA, which could be involved in its cytopathogenic mechanism.


Assuntos
Eritrócitos/metabolismo , Hemólise/fisiologia , Fosfolipases A/metabolismo , Trichomonas vaginalis/metabolismo , Animais , Cálcio/metabolismo , Relação Dose-Resposta a Droga , Humanos , Concentração de Íons de Hidrogênio , Fosfolipases A/antagonistas & inibidores , Ratos , Estearatos/farmacologia , Trichomonas vaginalis/enzimologia , Trichomonas vaginalis/patogenicidade , Virulência
11.
Bioorg Med Chem Lett ; 12(23): 3475-8, 2002 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-12419387

RESUMO

Several thiosemicarbazone derivatives of 5-nitrothiophene-2-carboxaldehyde were prepared by the simple process in which N(4)-thiosemicarbazone moiety was replaced by aliphatic, arylic and cyclic amine. Among these thiosemicarbazones compound 11 showed significant antiamoebic activity whereas compound 3 was more active antitrichomonal than the reference drug.


Assuntos
Aldeídos/química , Antiprotozoários/síntese química , Antiprotozoários/farmacologia , Compostos de Sulfidrila/química , Tiossemicarbazonas/química , Tiossemicarbazonas/farmacologia , Aldeídos/farmacologia , Aminas/química , Animais , Entamoeba histolytica/efeitos dos fármacos , Giardia lamblia/efeitos dos fármacos , Concentração Inibidora 50 , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade , Compostos de Sulfidrila/farmacologia , Trichomonas vaginalis/efeitos dos fármacos
12.
Arch. med. res ; 24(2): 183-7, jun. 1993. ilus, tab
Artigo em Inglês | LILACS | ID: lil-177005

RESUMO

Gossypol, a natural racemic mixture with action on NADP- and NAD-oxidoreductases from diverse species, has been proposed as a possible antiamebic medication considering several of its pharmacological properties. In this study it was found that malic enzyme and alcohol dehydrogenase from Entamoeba histolytica are strongly inhibited by (ñ)-gossypol, and both (+)- and (-)- enantiomers. The inhibition was of the noncompetitive type among their respective substrates in all cases. The (ñ)-, (+)-, (-)-gossypol half-maximal inhibitory concentrations (IC 50) for the malic enzyme were 3.71, 13.37 and 1.03 µM, and againts the alcohol dehydrogenase 79.64, 124.43 and 42.56 µM, respectively. Therefore, the (-) enantiomer resulted 3.6 and 13.0 times more potent than the racemic mixture and (+)- gossypol, respectively, to inhibit the malic enzyme, and 1.9 times and 2.9 times more potent than the racemic mixture and (+)-gossypol, respectively, against the alcohol dehydrogenase. Accordingly, one possible mechanism of the antiamebic affect of gossypol could be the inhibition of vital NADP-dependent enzymes as those analyzed in this study


Assuntos
Oxirredutases do Álcool/uso terapêutico , Entamoeba histolytica/patogenicidade , Gossipol/farmacologia , Malato Desidrogenase/biossíntese
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