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1.
Arq. bras. med. vet. zootec. (Online) ; 73(3): 598-604, May-June 2021. tab
Article in English | LILACS, VETINDEX | ID: biblio-1278360

ABSTRACT

The objective of the study was to evaluate the antiparasitic resistance against horse nematodes in the South of Rio Grande do Sul, Brazil. The results concerning the tests of anthelmintic efficacy on horses, stored in the database of the Parasitic Diseases Study Group (GEEP) - Veterinary Faculty, at the Federal University of Pelotas (UFPel), were carried out in the laboratory from 2018 to 2019. Stool samples were received from farms with breeding of adult female and male Criollo horses naturally infected, located in municipalities in the country's southern region. The antiparasitic agents tested were Triclorfon + Fenbendazole, Closantel + Albendazole, Ivermectin + Praziquantel, Fenbendazole, Ivermectin, Doramectin, Mebendazole and Moxidectin. Techniques such as Gordon and Whitlock, Coproculture and Fecal Egg Count Reduction Test were performed. Of all the antiparasitic drugs tested, it was observed that only treatments with Ivermectin 2% showed desired values. The observed results indicate that resistance to macrocyclic lactones is usual in equine parasites in this Brazilian region, despite the results with isolated Ivermectin.(AU)


O objetivo deste estudo é avaliar a resistência antiparasitária contra nematodeos de equinos no sul do Rio Grande do Sul, Brasil. Os resultados referentes aos testes de eficácia anti-helmíntica em cavalos, armazenados no banco de dados do Grupo de Estudos de Doenças Parasitárias (GEEP) - Faculdade de Veterinária, da Universidade Federal de Pelotas (UFPel), foram realizados em laboratório, no período de 2018 a 2019. Amostras de fezes foram recebidas de fazendas com criação de cavalos Crioulos adultos fêmeas e machos naturalmente infectados, localizadas em municípios da região Sul do país. Os agentes antiparasitários testados foram triclorfon + fenbendazol, closantel + ivermectina + praziquantel, fenbendazol, ivermectina, doramectina, mebendazol e moxidectina. Técnicas como Gordon e Whitlock, coprocultura e teste de redução da contagem de ovos fecais foram realizadas. De todos os antiparasitários testados, observou-se que apenas os tratamentos com ivermectina 2% apresentaram os valores desejados. Os resultados indicam que a resistência às lactonas macrocíclicas é comum em parasitas equinos nessa região brasileira, apesar dos resultados com ivermectina isolada.(AU)


Subject(s)
Animals , Drug Resistance, Multiple , Macrolides/analysis , Horses/parasitology , Anthelmintics/analysis , Parasite Egg Count/veterinary , Brazil , Parasitic Sensitivity Tests/veterinary , Antiparasitic Agents/analysis
2.
Mem. Inst. Oswaldo Cruz ; 115: e190348, 2020. tab, graf
Article in English | LILACS | ID: biblio-1091246

ABSTRACT

BACKGROUND It was previously demonstrated that CMC-20, a nitazoxanide and N-methyl-1H-benzimidazole hybrid molecule, had higher in vitro activity against Giardia intestinalis WB strain than metronidazole and albendazole and similar to nitazoxanide. OBJETIVES To evaluate the in vitro activity of CMC-20 against G. intestinalis strains with different susceptibility/resistance to albendazole and nitazoxanide and evaluate its effect on the distribution of parasite cytoskeletal proteins and its in vivo giardicidal activity. METHODS CMC-20 activity was tested against two isolates from patients with chronic and acute giardiasis, an experimentally induced albendazole resistant strain and a nitazoxanide resistant clinical isolate. CMC-20 effect on the distribution of parasite cytoskeletal proteins was analysed by indirect immunofluorescence and its activity was evaluated in a murine model of giardiasis. FINDINGS CMC-20 showed broad activity against susceptible and resistant strains to albendazole and nitaxozanide. It affected the parasite microtubule reservoir and triggered the parasite encystation. In this process, alpha-7.2 giardin co-localised with CWP-1 protein. CMC-20 reduced the infection time and cyst load in feces of G. muris infected mice similar to albendazole. MAIN CONCLUSIONS The in vitro and in vivo giardicidal activity of CMC-20 suggests its potential use in the treatment of giardiasis.


Subject(s)
Humans , Animals , Mice , Thiazoles/pharmacology , Albendazole/pharmacology , Giardia lamblia/drug effects , Cytoskeletal Proteins/drug effects , Antiprotozoal Agents/pharmacology , Thiazoles/chemistry , Time Factors , Albendazole/chemistry , Fluorescent Antibody Technique, Indirect , Parasitic Sensitivity Tests , Antiprotozoal Agents/chemistry
3.
Mem. Inst. Oswaldo Cruz ; 115: e190348, 2020. tab, graf
Article in English | LILACS | ID: biblio-1056773

ABSTRACT

BACKGROUND It was previously demonstrated that CMC-20, a nitazoxanide and N-methyl-1H-benzimidazole hybrid molecule, had higher in vitro activity against Giardia intestinalis WB strain than metronidazole and albendazole and similar to nitazoxanide. OBJETIVES To evaluate the in vitro activity of CMC-20 against G. intestinalis strains with different susceptibility/resistance to albendazole and nitazoxanide and evaluate its effect on the distribution of parasite cytoskeletal proteins and its in vivo giardicidal activity. METHODS CMC-20 activity was tested against two isolates from patients with chronic and acute giardiasis, an experimentally induced albendazole resistant strain and a nitazoxanide resistant clinical isolate. CMC-20 effect on the distribution of parasite cytoskeletal proteins was analysed by indirect immunofluorescence and its activity was evaluated in a murine model of giardiasis. FINDINGS CMC-20 showed broad activity against susceptible and resistant strains to albendazole and nitaxozanide. It affected the parasite microtubule reservoir and triggered the parasite encystation. In this process, alpha-7.2 giardin co-localised with CWP-1 protein. CMC-20 reduced the infection time and cyst load in feces of G. muris infected mice similar to albendazole. MAIN CONCLUSIONS The in vitro and in vivo giardicidal activity of CMC-20 suggests its potential use in the treatment of giardiasis.


Subject(s)
Humans , Animals , Mice , Thiazoles/pharmacology , Albendazole/pharmacology , Giardia lamblia/drug effects , Cytoskeletal Proteins/drug effects , Antiprotozoal Agents/pharmacology , Thiazoles/chemistry , Time Factors , Albendazole/chemistry , Fluorescent Antibody Technique, Indirect , Parasitic Sensitivity Tests , Antiprotozoal Agents/chemistry
4.
Rev. bras. parasitol. vet ; 29(1): e013119, 2020. tab, graf
Article in English | LILACS | ID: biblio-1058018

ABSTRACT

Abstract The objective of this study was to evaluate the efficacy of carvacryl acetate (CVA) and nanoencapsulated CVA (nCVA) on gastrointestinal nematodes of sheep. The CVA was nanoencapsulated with chitosan/gum arabic and the efficacy of nanoencapsulation (EE), yield, zeta potential, nanoparticle morphology and release kinetics at pH 3 and 8 were analyzed. Acute and subchronic toxicity were evaluated in rodents and reduction of egg counts in the faeces (FECRT) of sheep. The sheep were divided into four groups (n = 10): G1, 250 mg/kg CVA; G2, 250 mg/kg nCVA; G3, polymer matrix and G4: 2.5 mg/kg monepantel. EE and nCVA yield were 65% and 57%, respectively. The morphology of the nanoparticles was spherical, size (810.6±286.7 nm), zeta potential in pH 3.2 (+18.3 mV) and the 50% release of CVA at pHs 3 and 8 occurred at 200 and 10 h, respectively. nCVA showed LD50 of 2,609 mg/kg. CVA, nCVA and monepantel reduced the number of eggs per gram of faeces (epg) by 57.7%, 51.1% and 97.7%, respectively. The epg of sheep treated with CVA and nCVA did not differ from the negative control (P>0.05). Nanoencapsulation reduced the toxicity of CVA; however, nCVA and CVA presented similar results in the FECRT.


Resumo O objetivo deste trabalho foi avaliar a eficácia do acetato de carvacrila (ACV) e do ACV nanoencapsulado (nACV) sobre nematóides gastrintestinais de ovinos. O ACV foi nanoencapsulado com quitosana/goma arábica e foi analisada a eficácia de nanoencapsulamento (EE), o rendimento, potencial zeta, morfologia das nanopartículas e cinética de liberação em pH 3 e 8. Foram avaliadas as toxicidades aguda e subcrônica em roedores e a redução da contagem de ovos nas fezes (RCOF) de ovinos. Os ovinos foram divididos em quatro grupos (n = 10): G1, 250 mg/kg ACV; G2, 250 mg/kg de nACV; G3, matriz polimérica e G4: 2,5 mg/kg de monepantel. A EE e o rendimento de nACV foram de 65% e 57%, respectivamente. A morfologia das nanopartículas foi esférica, tamanho (810,6±286,7 nm), potencial zeta no pH 3,2 (+18,3 mV) e a liberação de 50% de CVA nos pHs 3 e 8 ocorreu às 200 e 10 h, respectivamente. nACV apresentou DL50 de 2.609 mg/kg. ACV, nACV e o monepantel reduziram a contagem de ovos por grama de fezes (opg) em 57,7%, 51,1% e 97,7%, respectivamente. A contagem de opg de ovelhas tratadas com ACV e nCVA não diferiu do controle negativo (P>0,05). O nanoencapsulamento reduziu a toxicidade do AVC; no entanto, nACV e ACV apresentaram resultados semelhantes na RCOF.


Subject(s)
Animals , Female , Sheep Diseases/drug therapy , Monoterpenes/administration & dosage , Gastrointestinal Tract/parasitology , Nanocapsules/administration & dosage , Anthelmintics/administration & dosage , Nematoda/drug effects , Nematode Infections/drug therapy , Parasite Egg Count , Rodentia , Sheep Diseases/parasitology , Sheep , Toxicity Tests , Parasitic Sensitivity Tests , Monoterpenes/toxicity , Nanocapsules/toxicity , Feces/parasitology , Real-Time Polymerase Chain Reaction , Anthelmintics/toxicity , Mice , Nematoda/isolation & purification , Nematoda/classification , Nematode Infections/parasitology
5.
Rev. bras. parasitol. vet ; 28(4): 700-707, Oct.-Dec. 2019. tab, graf
Article in English | LILACS | ID: biblio-1057997

ABSTRACT

Abstract The aim here is to present data on the efficacy of anthelmintics in sheep flocks in Rio de Janeiro, Brazil, and to discuss the interpretation of the fecal egg count reduction test (FECRT) for each nematode genus. Fecal eggs counts and pre- and post-treatment coprocultures were performed, the former to evaluate the efficacy of and the latter to determine the overall parasite prevalence. An additional efficacy test was performed at Farm # 1 a year after the initial test. Severe anthelmintic resistance was found for the flocks, with no FECRT sensitivity at any of the 22 farms evaluated. However, an analysis of the infective larvae showed that some drugs were effective against certain parasitic genera; i.e., levamisole was more effective against Haemonchus spp. and moxidectin against Trichostrongylus spp. In the additional FECRT performed at Farm # 1, moxidectin and nitroxynil were ineffective separately, but when applied in combination they were highly effective due to their efficacy against Haemonchus (nitroxynil) and Trichostrongylus (moxidectin), respectively. The use of the FECRT targeting the parasitic nematode species prevalent on farms may make it possible to choose more effective anthelmintics.


Resumo O objetivo deste trabalho foi apresentar dados sobre a eficácia de anti-helmínticos em rebanhos ovinos no Rio de Janeiro, Brasil, e discutir a interpretação do teste de redução da contagem de ovos nas fezes (TRCOF) para cada gênero de nematoide. A contagem de ovos fecais (OPG) e coprocultura pré e pós-tratamento foram realizadas para avaliar a eficácia e a prevalência geral do parasito, respectivamente. Um teste de eficácia adicional foi realizado na Fazenda # 1 após um ano do teste inicial. Resistência anti-helmíntica grave foi encontrada, não havendo sensibilidade no TRCOF em nenhuma das 22 fazendas avaliadas. No entanto, na análise das larvas infectantes observou-se que algumas drogas foram eficazes contra certos gêneros parasitários; por exemplo, o levamisol foi mais eficaz contra Haemonchus spp. e a moxidectina contra Trichostrongylus spp. No TRCOF adicional realizado na Fazenda 1, a moxidectina e o nitroxinil foram ineficazes separadamente, mas quando aplicados em combinação, foram altamente eficazes devido à sua eficácia contra Haemonchus spp. (nitroxinil) e Trichostrongylus spp. (moxidectina), respectivamente. O TRCOF visando às espécies de nematoides parasitas prevalentes nas fazendas pode possibilitar a escolha de anti-helmínticos mais eficazes.


Subject(s)
Animals , Parasite Egg Count , Sheep Diseases/parasitology , Feces/parasitology , Anthelmintics/therapeutic use , Nematoda/drug effects , Drug Resistance , Sheep , Parasitic Sensitivity Tests , Anthelmintics/pharmacology , Nematoda/isolation & purification , Nematoda/classification
6.
Rev. bras. parasitol. vet ; 28(4): 807-811, Oct.-Dec. 2019. tab
Article in English | LILACS | ID: biblio-1057983

ABSTRACT

Abstract Gastrointestinal Nematode Infection (GIN) are the main constraint to the production of small ruminants. Studies of medicinal plants have been an important alternative in the effort to control these parasites. Therefore, the purpose of this study was to evaluate the in vitro ovicidal and larvicidal activity of essential oil of Rosmarinus officinalis. The oil was extracted, analyzed by gas chromatography and tested on GIN eggs and larvae in six concentrations, 227.5mg/mL, 113.7mg/mL, 56.8mg/mL, 28.4mg/mL, 14.2mg/mL and 7.1mg/mL. To determine the ovicidal activity, GIN eggs were recovered from sheep feces and incubated for 48h with different concentrations of the oil. For the evaluation of larval migration, third-stage larvae (L3) were obtained by fecal culture, and associated with the essential oil for 24h at the same concentrations, after which they were left for another 24 hours on microsieves, followed by the count of migrating and non-migrating larvae. The assays of R. officinalis oil showed a significant (p<0.05) 97.4% to 100% inhibition of egg hatching and a significant (p<0.05) 20% to 74% inhibition of larval migration. The main constituent revealed by gas chromatography was Eucalyptol. The results indicate that R. officinalis essential oil has ovicidal and larvicidal activity on sheep GINs.


Resumo As infecções por nematódeos gastrintestinais (ING) constituem a maior limitação à produção de pequenos ruminantes. Na busca do controle desses parasitos, estudos com plantas medicinais têm sido uma importante alternativa. Visto isto, o estudo desenvolvido teve como objetivo avaliar a ação ovicida e larvicida in vitro do óleo essencial de Rosmarinus officinalis. O óleo foi extraído, analisado por cromatografia gasosa e testado sobre ovos e larvas de ING em seis concentrações, 227,5mg/mL; 113,7mg/mL; 56,8mg/mL; 28,4mg/mL; 14,2mg/mL; 7,1mg/mL. Para determinar a ação ovicida, ovos de ING foram recuperados de fezes de ovinos e incubados por 48h com as diferentes concentrações do óleo. Na avaliação da migração das larvas, as larvas de terceiro estágio (L3) foram obtidas por coprocultura, e associadas ao óleo essencial por 24h nas mesmas concentrações, permanecendo por mais 24h em microtamises, seguindo-se a contagem de larvas que migraram e que não migraram. Os testes in vitro com o óleo de R. officinalis mostraram o nível de significância (p<0.05) 97,4% a 100% na inibição da eclodibilidade e 20% a 74% na inibição da migração das larvas. Na análise por cromatografia gasosa o constituinte majoritário foi o eucaliptol. Os resultados apresentados mostram que o óleo essencial de R. officinalis possui ação ovicida e larvicida sobre ING de ovinos.


Subject(s)
Animals , Ovum/drug effects , Oils, Volatile/pharmacology , Sheep/parasitology , Plant Extracts/pharmacology , Rosmarinus/chemistry , Larva/drug effects , Nematoda/drug effects , Oils, Volatile/isolation & purification , Chromatography, Gas , Parasitic Sensitivity Tests , Dose-Response Relationship, Drug , Nematoda/isolation & purification
7.
Rev. bras. parasitol. vet ; 28(4): 644-651, Oct.-Dec. 2019. tab, graf
Article in English | LILACS | ID: biblio-1057972

ABSTRACT

Abstract This study aimed to evaluate the anthelmintic activity of Eucalyptus citriodora essential oil and citronellal on sheep gastrointestinal nematodes. Essential oil composition was determined by gas chromatography mass spectrometry. The substances were evaluated in vitro using adult worm motility test (AWMT) and transmission electron microscopy (TEM). The acute toxicity test in mice and the fecal egg count reduction test (FECRT) in sheep were performed. Citronellal was confirmed as the essential oil major constituent (63.9%). According to the AWMT, 2 mg/mL of essential oil and citronellal completely inhibited Haemonchus contortus motility at 6 h post exposure. H. contortus exposed to essential oil and citronellal exhibited internal ultrastructural modifications. The lethal dose 50 values in mice were 5,000 and 2,609 mg/kg for essential oil and citronellal, respectively. E. citriodora essential oil reduced sheep epg at 14 days post treatment by 69.5% (P<0.05). No significant differences were observed in epg between the citronellal and negative control groups (P>0.05). The interaction between citronellal and other constituents in the essential oil may be relevant for its in vivo anthelmintic activity. Thus, E. citriodora essential oil and citronellal pharmacokinetic studies may help elucidate the anthelmintic activity of these compounds.


Resumo Este trabalho objetivou avaliar a atividade anti-helmíntica do óleo essencial de Eucalyptus citriodora e citronelal sobre nematoides gastrintestinais de ovinos. A composição do óleo essencial foi determinada por cromatografia gasosa acoplada à espectrometria de massas. As substâncias foram avaliadas in vitro utilizando-se teste de motilidade de vermes adultos (AWMT) e microscopia eletrônica de transmissão (TEM). Teste de toxicidade aguda em camundongos e teste de redução da contagem de ovos fecais (FECRT) em ovinos foram realizados. Citronelal foi confirmado como componente majoritário do óleo essencial (63,9%). No AWMT, 2 mg/mL de óleo essencial e citronelal inibiram completamente a motilidade de H. contortus 6 h pós-exposição. H. contortus expostos ao óleo essencial e citronelal exibiram modificações ultraestruturais internas. Os valores da dose letal 50 em camundongos foram 5.000 e 2.609 mg/kg para óleo essencial e citronelal, respectivamente. Óleo essencial de E. citriodora reduziu opg de ovinos 14 dias pós-tratamento em 69,5% (P<0,05). Não houve diferença significativa de opg entre grupo controle negativo e citronelal (P>0,05). A interação entre citronelal e outros constituintes do óleo essencial pode ser relevante na atividade anti-helmíntica in vivo. Portanto, avaliação farmacocinética do óleo essencial de E. citriodora e citronelal pode auxiliar a elucidar a atividade anti-helmíntica desses compostos.


Subject(s)
Animals , Female , Mice , Sheep Diseases/parasitology , Oils, Volatile/pharmacology , Sheep/parasitology , Eucalyptus/chemistry , Haemonchiasis/veterinary , Haemonchus/drug effects , Anthelmintics/pharmacology , Parasite Egg Count , Oils, Volatile/isolation & purification , Parasitic Sensitivity Tests , Microscopy, Electron, Transmission , Haemonchiasis/parasitology , Haemonchus/isolation & purification , Haemonchus/ultrastructure , Gas Chromatography-Mass Spectrometry
8.
Bol. latinoam. Caribe plantas med. aromát ; 18(6): 533-543, nov. 2019. tab
Article in English | LILACS | ID: biblio-1100255

ABSTRACT

The livestock sector is continuously facing problems in controlling parasitic diseases especially Haemonchosis due to emergence of anthelminthic resistance and failure in vaccination control programmes. Therefore, to increase milk and meat production and emerging demand of meat free from drug residues development of new alternative approaches are appealing for prevention and control of Haemonchosis in small ruminants. Among alternatives, plants driven essentials oils have shown promising results in control of Haemonchus contortus infection at various concentrations by different assays including egg hatch assay, larval development assay, larval exsheathment assay and adult motility assay. Essential oils are complex mixtures of various impulsive or volatile compounds which have potential to control Haemonchosis. The current study reviews the therapeutic effects of essential oils of plants against Haemonchus contortus and to be used them against Haemonchus contortus for future perspectives.


El sector ganadero enfrenta continuamente problemas para controlar las enfermedades parasitarias, especialmente la hemoncosis, debido a la aparición de resistencia antihelmíntica y al fracaso en los programas de control de vacunación. Por lo tanto, para aumentar la producción de leche y carne, y la demanda emergente de carne libre de residuos de medicamentos, el desarrollo de nuevos enfoques alternativos es atractivo para la prevención y el control de la hemoncosis en pequeños rumiantes. Entre las alternativas, los aceites esenciales producidos por las plantas han mostrado resultados prometedores en el control de la infección por Haemonchus contortus a diversas concentraciones mediante diferentes ensayos, incluido el análisis de eclosión de huevos, el desarrollo de larvas, el análisis de vaciado de larvas y el ensayo de motilidad en adultos. Los aceites esenciales son mezclas complejas de varios compuestos impulsivos o volátiles que tienen potencial para controlar la hemonchosis. Este estudio revisa los efectos terapéuticos de los aceites esenciales de las plantas contra Haemonchus contortus y evalúa sus perspectivas futuras como agentes para combatir las enfermedades causadas por este parásito.


Subject(s)
Animals , Plants/chemistry , Ruminants/parasitology , Oils, Volatile/pharmacology , Plant Extracts/pharmacology , Haemonchus/drug effects , Anthelmintics/pharmacology , Oils, Volatile/isolation & purification , Parasitic Sensitivity Tests , Haemonchiasis/drug therapy , Anthelmintics/isolation & purification
9.
Rev. bras. parasitol. vet ; 28(2): 210-214, Apr.-June 2019. tab
Article in English | LILACS | ID: biblio-1013748

ABSTRACT

Abstract Cystic echinococcosis (CE) are commonly found in the liver and lungs of affected hosts. The treatment approach is usually surgical, or giving drugs in conjunction before surgery to kill protoscolices, to avoid anaphylactic shock from leakage of hydatid fluid into the peritoneum and to decrease opportunities for recurrences. The present study was to evaluate the in vitro scolicidal efficacy of hydroalcoholic extract of Punica granatum peel and Nigella sativa, on the protoscolices of CE that collected from the lungs of infected camels. Different concentrations of extracts with different exposure times were used and a viability assay was applied to measure the scolicidal effect. N. sativa showed its highest scolicidal efficacy at 100 mg/mL and 10 mg/mL concentrations after 30 and 60 min. P. granatum peel extract showed its maximum scolicidal efficacy at 100 mg/mL concentration after 120 min. All experiments of the current study revealed that the extracts of both N. sativa and P. granatum had a scolicidal effects on the protoscolices of camel hydatid cysts. It could be concluded that N. sativa extract is more potent than P. granatum peel extract regarding scolicidal effect, but the efficacies of both extracts were of moderate significant correlation to exposure time and concentrations.


Resumo Os cistos hidáticos (equinococose cística, CE) são comumente encontrados no fígado e nos pulmões dos hospedeiros afetados. A abordagem do tratamento geralmente é cirúrgica, e algumas drogas são administradas em conjunto antes da cirurgia para matar protoscólices e evitar choque anafilático devido ao vazamento de fluido hidático no peritônio e diminuir as oportunidades de recorrência. O presente estudo foi avaliar a eficácia in-vitro do extrato hidroalcoólico de casca de Punica granatum e Nigella sativa, sobre os protoescólices de cistos hidáticos, que foram coletados dos pulmões de camelos infectados. Concentrações dos extratos com diferentes tempos de exposição foram utilizados e um ensaio de viabilidade foi aplicado para medir o efeito escolicida. A N. sativa apresentou sua maior eficácia escolicida nas concentrações de 100 mg/mL e 10 mg/mL após 30 e 60 min. O extrato de casca de P. granatum mostrou sua máxima eficácia escolicida na concentração de 100 mg/mL após 120 min. Todos os experimentos do presente estudo revelaram que os extratos de N. sativa e P. granatum tiveram efeito escolicida dependente da dose e do tempo nos protoescólices dos cistos hidáticos de camelo. Pode-se concluir que o extrato de N. sativa é mais potente que o extrato de casca de P. granatum em relação ao efeito escolicida, mas a eficácia de ambos os extratos foi de correlação significativa moderada com o tempo de exposição e as concentrações.


Subject(s)
Animals , Plant Extracts/pharmacology , Nigella sativa/chemistry , Lythraceae/chemistry , Echinococcus/drug effects , Camelus/parasitology , Parasitic Sensitivity Tests , Echinococcosis/parasitology , Echinococcus/isolation & purification
10.
Rev. bras. parasitol. vet ; 27(4): 423-429, Oct.-Dec. 2018. tab, graf
Article in English | LILACS | ID: biblio-977935

ABSTRACT

Abstract This study aimed to evaluate the occurrence of nematode resistance to anthelmintics on sheep herds from the semi-arid region of Paraíba, Northeastern Brazil. Fecal Egg Count Reduction Test (FECRT) was carried out on 20 properties. In each herd, 30 animals were divided into five groups containing six animals each: group I, treated with albendazole 10%, 4 mg/kg; group II, ivermectin 0.08%, 0.2 mg/kg; group III, closantel 10%, 10 mg/kg; group IV, levamisole hydrochloride 5%, 5 mg/kg; and group V, monepantel 2.5%, 2.5 mg/kg. All treatments were administered orally as a single dose. Fecal samples were collected on days zero and 10 after treatment, to perform FECRT and coprocultures. Multiresistance was observed in all the properties; 95% had high resistance to albendazole, 85% to ivermectin, 80% to closantel, 40% to levamisole, and 45% to monepantel. On property 15, where monepantel was ineffective, a second FECRT for this anthelmintic was carried out 4 months after the first, resulting in 75% efficacy. Immediately after the FECRT result, two ewes were euthanized and necropsied, and Haemonchus contortus, Trichostrongylus axei, Trichostrongylus colubriformis, Oesophagostomum columbianum, and Trichuris ovis were recovered. It was concluded that the resistance of sheep gastrointestinal nematodes to antthelmintic, including monepantel, is high.


Resumo O objetivo deste estudo foi avaliar a ocorrência de resistência de nematódeos a anti-helmínticos em rebanhos ovinos do semiárido da Paraíba, Nordeste do Brasil. Testes de Redução na Contagem de Ovos Fecais (TRCOF) foram conduzidos em 20 propriedades. Em cada rebanho, 30 animais foram selecionados e foram divididos em cinco grupos contendo seis animais cada: grupo I, tratado com albendazol 10%, 10 mg/kg; grupo II, ivermectina 0,08%, 0,2 mg/kg; grupo III, closantel 10%, 10 mg/kg; grupo IV, cloridrato de levamisol 5%, 5 mg/kg; grupo V, monepantel 2,5%, 2,5 mg/kg. Todos os tratamentos foram administrados via oral, em dose única. Amostras fecais foram coletadas nos dias zero e 10 após os tratamentos, para a realização do TRCOF e coproculturas. Multirresistência foi observada em todas as propriedades; 95% dos rebanhos obtiveram alta resistência ao albendazole, 85% a ivermectina, 80% ao closantel, 40% ao levamisole, e 45% a monepantel. Na propriedade 15, onde o monepantel foi ineficaz, um segundo TRCOF foi conduzido para este fármaco 4 meses após o primeiro, resultando em 75% de eficácia. Imediatamente após o resultado do TRCOF, duas ovelhas foram eutanaziadas e necropsiadas, e Haemonchus contortus, Trichostrongylus axei, Trichostrongylus colubriformis, Oesophagostomum columbianum, e Trichuris ovis foram recuperados. Concluiu-se que a resistência dos nematódeos gastrintestinais de ovinos aos anti-helmínticos, incluindo o monepantel, é alta.


Subject(s)
Animals , Male , Female , Sheep Diseases/parasitology , Nematoda/drug effects , Nematode Infections/veterinary , Antinematodal Agents/pharmacology , Sheep , Drug Resistance, Multiple , Parasitic Sensitivity Tests , Feces/parasitology , Nematoda/isolation & purification , Nematode Infections/parasitology
11.
Rev. bras. parasitol. vet ; 27(4): 473-480, Oct.-Dec. 2018. tab, graf
Article in English | LILACS | ID: biblio-977930

ABSTRACT

Abstract Haemonchus contortus is a gastrointestinal nematode that is responsible for high mortality rates in ruminant herds. The resistance of nematodes to synthetic anthelmintics is widespread and requires a continuous search for new bioactive molecules, such as proteins. The objective of this study was to evaluate the anthelmintic potential of a protease purified from the latex of Ficus benjamina against H. contortus . Fresh latex was collected from plants via small incisions in the green stems, the rubber was removed by centrifugation, and the latex protein extract (LPE) was obtained. After LPE fractionation with ammonium sulfate and chromatography of the fraction containing the highest proteolytic activity on CM-cellulose, a cysteine protease (FbP) was purified. FbP has a molecular mass of approximately 23.97 kDa, and its proteolytic activity was stable between pH 6.0 and pH 10 and over a broad temperature range, with optimum activity at 60 °C. FbP inhibited both the development and exsheathment of H. contortus larvae, with 50% effective concentrations of 0.26 and 0.79 mg/mL, respectively. We conclude that this cysteine protease from F. benjamina latex with anthelmintic activity against H. contortus could be a promising alternative for the development of products for use in parasite control programmes.


Resumo Haemonchus contortus é um nematoide gastrintestinal, responsável por altas taxas de mortalidade em rebanhos de pequenos ruminantes. A resistência dos nematoides aos anti-helmínticos sintéticos está generalizada e requer uma busca contínua por novos compostos bioativos, como as proteínas. O objetivo deste trabalho foi avaliar o potencial anti-helmíntico da protease purificada do látex de Ficus benjamina contra H. contortus . O látex fresco foi coletado das plantas por pequenas incisões nas hastes verdes e o extrato proteico de látex (EPL) foi obtido. Após o fracionamento do EPL com sulfato de amônio e cromatografia da fração contendo a maior atividade proteolítica da CM-Celulose, uma protease cisteínica (FbP) foi purificada. A FbP tem massa molecular de cerca de 23,97 kDa, a atividade proteolítica foi estável entre pH 6,0 e pH 10 e ao longo de uma ampla faixa de temperatura, com atividade ótima a 60 °C. A FbP inibiu tanto o desenvolvimento quanto o desembainhamento das larvas de H. contortus, com 50% de inibição nas concentrações de 0,26 e 0,79 mg/mL, respectivamente. Concluímos que esta protease cisteínica do látex de F. benjamina, com ação anti-helmíntica contra H. contortus, pode ser uma alternativa promissora para o desenvolvimento de produtos a serem utilizados em programas de controle de parasitos.


Subject(s)
Animals , Plant Extracts/pharmacology , Ficus/chemistry , Cysteine Proteases/pharmacology , Haemonchus/drug effects , Latex/chemistry , Anthelmintics/pharmacology , Sheep/parasitology , Parasitic Sensitivity Tests , Electrophoresis, Polyacrylamide Gel , Cysteine Proteases/isolation & purification
12.
Rev. Soc. Bras. Med. Trop ; 51(6): 849-853, Nov.-Dec. 2018. tab, graf
Article in English | LILACS | ID: biblio-1041494

ABSTRACT

Abstract INTRODUCTION Leishmaniasis, Chagas disease, and malaria cause morbidity globally. The drugs currently used for treatment have limitations. Activity of cinnamic acid analogs against Leishmania spp., Trypanosoma cruzi, and Plasmodium falciparum was evaluated in the interest of identifying new antiprotozoal compounds. METHODS In vitro effects of analogs against L. braziliensis, L. infantum chagasi, T. cruzi, and P. falciparum, and hemolytic and cytotoxic activities on NCTC 929 were determined. RESULTS Three analogs showed leishmanicidal and tripanocidal activity. No antiplasmodial, hemolytic, or cytotoxic activity was observed. CONCLUSIONS Antiprotozoal activity of analogs against L. infantum braziliensis, L. infantum chagasi, and T. cruzi was demonstrated.


Subject(s)
Plasmodium falciparum/drug effects , Trypanosoma cruzi/drug effects , Cinnamates/pharmacology , Leishmania/drug effects , Antiprotozoal Agents/pharmacology , Cinnamates/chemistry , Parasitic Sensitivity Tests , Antiprotozoal Agents/chemistry
13.
An. acad. bras. ciênc ; 90(1): 479-483, Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-886924

ABSTRACT

ABSTRACT Giardia duodenalis is a worldwide intestinal parasite and is one of the most frequent protozoa species infecting dogs and cats. This study aimed to modify the methodology of Alere GIARDIA Ag TEST KIT for its use in frozen fecal sediments with different storage times in a freezer (-20°C), thus expanding the range of use of this methodology. One hundred fecal sediments from dogs (n=50) and cats (n=50) previously examined by optical microscopy for Giardia cysts were selected for this study. The agreement between the modified immunochromatography and microscopy results was calculated by Kappa coefficient. To evaluate the performance of the modified immunochromatography assay on samples with different storage time, the fecal sediments were divided into three groups according to the time of storage in a freezer: (a) ≤ 1 year (n=37); (b) > 1 year and ≤ 3 years (n=39); (c) > 10 years (max. 13 years) (n=24). The results obtained by the modified immunochromatography assay demonstrates a higher sensitivity of this technique when compared with microscopy, regardless of the frozen storage time. These results allow for the use of this methodology in a greater scope of analysis, especially in frozen fecal sediment triage in sample collections, enabling epidemiological and comparative analysis along different decades.


Subject(s)
Animals , Cats , Dogs , Chromatography, Affinity/veterinary , Giardia lamblia/isolation & purification , Feces/parasitology , Time Factors , Chromatography, Affinity/methods , Parasitic Sensitivity Tests/methods , Parasitic Sensitivity Tests/veterinary , Freezing , Microscopy/methods , Microscopy/veterinary
14.
Rev. Soc. Bras. Med. Trop ; 51(1): 52-56, Jan.-Feb. 2018. graf
Article in English | SES-SP, LILACS, SES-SP, SESSP-IDPCPROD, SES-SP | ID: biblio-897053

ABSTRACT

Abstract INTRODUCTION: Approximately seven to eight million people worldwide have Chagas disease. In Brazil, benznidazole is the most commonly used active drug against Trypanosoma cruzi; however, its efficacy is limited, and side effects are frequent. Recent studies suggest that amiodarone may be beneficial in the treatment of this disease, by exerting anti-T. cruzi action. This study evaluated changes in T. cruzi cell count in in vitro cultures subjected to different doses of benznidazole, amiodarone, and their combination. METHODS: T. cruzi (Y strain) cultures containing approximately 100,000 cells were treated with either 100mg, 50mg, 25mg, 12.5mg, or 10mg of benznidazole, amiodarone, or their combination. On the 4th day, cell count was compared to the baseline data. RESULTS: On the 4th day, no parasites were observed in any of the treated cultures. CONCLUSIONS: Benznidazole and amiodarone were equally effective in eliminating T. cruzi in culture. The combination of the two drugs was also equally effective, but our data cannot demonstrate synergism, as similar results were obtained when the drugs were tested individually or in combination. It is suggested that this study be repeated with other T. cruzi strains to determine whether similar results can be obtained again.


Subject(s)
Animals , Trypanocidal Agents/pharmacology , Trypanosoma cruzi/drug effects , Parasitic Sensitivity Tests , Amiodarone/pharmacology , Nitroimidazoles/pharmacology , Trypanocidal Agents/administration & dosage , Dose-Response Relationship, Drug , Drug Combinations , Amiodarone/administration & dosage , Mice , Nitroimidazoles/administration & dosage
15.
Mem. Inst. Oswaldo Cruz ; 113(2): 119-125, Feb. 2018. tab, graf
Article in English | LILACS | ID: biblio-894893

ABSTRACT

BACKGROUND Treatment-refractory visceral leishmaniasis (VL) has become an important problem in many countries. OBJECTIVES We evaluated the antimony-resistance mechanisms of Leishmania infantum isolated from VL patients refractory or responsive to treatment with pentavalent antimony. METHODS Strains isolated from antimony-refractory patients (in vitro antimony-resistant isolates) and antimony-responsive patients (in vitro antimony-sensitive isolates) were examined. Morphological changes were evaluated by transmission electron microscopy after trivalent antimony exposure. P-glycoprotein (P-gp) efflux pump activity was evaluated using the pump-specific inhibitor verapamil hydrochloride, and the role of thiol in trivalent antimony resistance was investigated using the enzymatic inhibitor L-buthionine sulfoximine. FINDINGS Antimony treatment induced fewer alterations in the cellular structure of L. infantum resistant isolates than in that of sensitive isolates. P-gp efflux activity was not involved in antimony resistance in these isolates. Importantly, the resistant isolates contained higher levels of thiol compared to the sensitive isolates, and inhibition of thiol synthesis in the resistant isolates recovered their sensitivity to trivalent antimony treatment, and enhanced the production of reactive oxygen species in promastigotes exposed to the drug. MAIN CONCLUSIONS Our results demonstrate that isolates from patients with antimony-refractory VL exhibited higher thiol levels than antimony-sensitive isolates. This indicates that redox metabolism plays an important role in the antimony-resistance of New World VL isolates.


Subject(s)
Drug Resistance , Leishmaniasis, Visceral/parasitology , Antimony/pharmacology , Buthionine Sulfoximine , Parasitic Sensitivity Tests , Enzyme Inhibitors
16.
Mem. Inst. Oswaldo Cruz ; 113(8): e170452, 2018. tab, graf
Article in English | LILACS | ID: biblio-955116

ABSTRACT

BACKGROUND Malaria is responsible for 429,000 deaths per year worldwide, and more than 200 million cases were reported in 2015. Increasing parasite resistance has imposed restrictions to the currently available antimalarial drugs. Thus, the search for new, effective and safe antimalarial drugs is crucial. Heterocyclic compounds, such as dihydropyrimidinones (DHPM), synthesised via the Biginelli multicomponent reaction, as well as bicyclic compounds synthesised from DHPMs, have emerged as potential antimalarial candidates in the last few years. METHODS Thirty compounds were synthesised employing the Biginelli multicomponent reaction and subsequent one-pot substitution/cyclisation protocol; the compounds were then evaluated in vitro against chloroquine-resistant Plasmodium falciparum parasites (W2 strain). Drug cytotoxicity in baseline kidney African Green Monkey cells (BGM) was also evaluated. The most active in vitro compounds were evaluated against P. berghei parasites in mice. Additionally, we performed an in silico target fishing approach with the most active compounds, aiming to shed some light into the mechanism at a molecular level. RESULTS The synthetic route chosen was effective, leading to products with high purity and yields ranging from 10-84%. Three out of the 30 compounds tested were identified as active against the parasite and presented low toxicity. The in silico study suggested that among all the molecular targets identified by our target fishing approach, Protein Kinase 3 (PK5) and Glycogen Synthase Kinase 3β (GSK-3β) are the most likely molecular targets for the synthesised compounds. CONCLUSIONS We were able to easily obtain a collection of heterocyclic compounds with in vitro anti-P. falciparum activity that can be used as scaffolds for the design and development of new antiplasmodial drugs.


Subject(s)
Drug Design , Parasitic Sensitivity Tests , Antimalarials/chemical synthesis , Antimalarials/pharmacology , Pyrimidinones , Pyrroles
17.
Mem. Inst. Oswaldo Cruz ; 113(12): e180377, 2018. graf
Article in English | LILACS | ID: biblio-1040587

ABSTRACT

Ascorbate peroxidase (APX) is a redox enzyme of the trypanothione pathway that converts hydrogen peroxide (H2O2) into water molecules. In the present study, the APX gene was overexpressed in Leishmania braziliensis to investigate its contribution to the trivalent antimony (SbIII)-resistance phenotype. Western blot results demonstrated that APX-overexpressing parasites had higher APX protein levels in comparison with the wild-type line (LbWTS). APX-overexpressing clones showed an 8-fold increase in the antimony-resistance index over the parental line. In addition, our results indicated that these clones were approximately 1.8-fold more tolerant to H2O2 than the LbWTS line, suggesting that the APX enzyme plays an important role in the defence against oxidative stress. Susceptibility tests revealed that APX-overexpressing L. braziliensis lines were more resistant to isoniazid, an antibacterial agent that interacts with APX. Interestingly, this compound enhanced the anti-leishmanial SbIII effect, indicating that this combination represents a good strategy for leishmaniasis chemotherapy. Our data demonstrate that APX enzyme is involved in the development of L. braziliensis antimony-resistance phenotype and may be an attractive therapeutic target in the design of new strategies for leishmaniasis treatment.


Subject(s)
Leishmania braziliensis/drug effects , Leishmania braziliensis/enzymology , Ascorbate Peroxidases/metabolism , Antimony/pharmacology , Antiprotozoal Agents/pharmacology , Phenotype , Drug Resistance , Gene Expression Regulation, Enzymologic , Protozoan Proteins/metabolism , Blotting, Western , Oxidative Stress , Parasitic Sensitivity Tests
18.
An. acad. bras. ciênc ; 89(4): 3005-3013, Oct.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-886853

ABSTRACT

ABSTRACT Leishmaniasis and trypanosomiasis are globally widespread parasitic diseases which have been responsible for high mortality rates. Since drugs available for their treatment are highly hepatotoxic, nephrotoxic and cardiotoxic, adherence to therapy has been affected. Thus, the search for new, more effective and safer drugs for the treatment of these diseases is necessary. Natural products have stood out as an alternative to searching for new bioactive molecules with therapeutic potential. In this study, the chemical composition and antiparasitic activity of the essential oil from Protium ovatum leaves against trypomastigote forms of Trypanosoma cruzi and the promastigote forms of Leishmania amazonensis were evaluated. The essential oil was promising against trypomastigote forms of T. cruzi (IC50= 28.55 μg.mL-1) and L. amazonensis promastigotes (IC50 = 2.28 μg.mL-1). Eighteen chemical constituents were identified by Gas Chromatography coupled to Mass Spectrometry (GC-MS) in the essential oil, whose major constituents were spathulenol (17.6 %), caryophyllene oxide (16.4 %), β-caryophyllene (14.0 %) and myrcene (8.4 %). In addition, the essential oil from P. ovatum leaves had moderate cytotoxicity against LLCMK2 adherent epithelial cell at the concentration range under analysis (CC50 = 150.9 μg.mL-1). It should be highlighted that this is the first report of the chemical composition and anti-Trypanosoma cruzi and anti-Leishmania amazonensis activities of the essential oil from Protium ovatum leaves.


Subject(s)
Trypanocidal Agents/pharmacology , Trypanosoma cruzi/drug effects , Leishmania braziliensis/drug effects , Oils, Volatile/pharmacology , Burseraceae/chemistry , Trypanocidal Agents/isolation & purification , Inhibitory Concentration 50 , Parasitic Sensitivity Tests , Gas Chromatography-Mass Spectrometry
19.
Rev. Soc. Bras. Med. Trop ; 50(1): 126-129, Jan.-Feb. 2017. tab
Article in English | LILACS | ID: biblio-1041397

ABSTRACT

Abstract: INTRODUCTION: The activity of garlic oil extract against Schistosoma japonicum cercariae was evaluated. METHODS: The in vitro and in vivo cercaricidal activities against S. japonicum larvae were determined. RESULTS: Exposure to ≥ 10-6 (v/v) garlic emulsions for 30 min led to 100% cercariae mortality; pre-exposure treatment with ≥ 10-4 (v/v) garlic emulsions showed 100% preventive efficacy against S. japonicum infection, while pre-treatment with 10-5 and 10-6 (v/v) emulsions achieved 20%-40% preventive efficacy and 35.2%-63.6% worm burden reduction. CONCLUSIONS: Garlic oil extract has activity against S. japonicum larvae and a promising preventive efficacy against S. japonicum infection.


Subject(s)
Animals , Female , Schistosoma japonicum/drug effects , Plant Extracts/pharmacology , Cercaria/drug effects , Garlic/chemistry , Time Factors , Parasitic Sensitivity Tests , Mice
20.
Rev. Soc. Bras. Med. Trop ; 50(1): 52-60, Jan.-Feb. 2017. tab, graf
Article in English | LILACS | ID: biblio-842826

ABSTRACT

ABSTRACT INTRODUCTION: Cutaneous leishmaniasis (CL) is a tropical disease that affects millions of individuals worldwide. The current drugs for CL may be effective but have serious side effects; hence, alternatives are urgently needed. Although plant-derived materials are used for the treatment of various diseases in 80% of the global population, the validation of these products is essential. Gelatin capsules containing dried Artemisia annua leaf powder were recently developed as a new herbal formulation (totum) for the oral treatment of malaria and other parasitic diseases. Here, we aimed to determine the usefulness of A. annua gel capsules in CL. METHODS: The antileishmanial activity and cytotoxicity of A. annua L. capsules was determined via in vitro and in vivo studies. Moreover, a preliminary evaluation of its therapeutic potential as antileishmanial treatment in humans was conducted in 2 patients with uncomplicated CL. RESULTS: Artemisia annua capsules showed moderate in vitro activity in amastigotes of Leishmania (Viannia) panamensis; no cytotoxicity in U-937 macrophages or genotoxicity in human lymphocytes was observed. Five of 6 (83.3%) hamsters treated with A. annua capsules (500mg/kg/day) for 30 days were cured, and the 2 examined patients were cured 45 days after initiation of treatment with 30g of A. annua capsules, without any adverse reactions. Both patients remained disease-free 26 and 24 months after treatment completion. CONCLUSION: Capsules of A. annua L. represent an effective treatment for uncomplicated CL, although further randomized controlled trials are needed to validate its efficacy and safety.


Subject(s)
Humans , Animals , Male , Female , Adult , Plant Extracts/therapeutic use , Plant Extracts/pharmacology , Leishmaniasis, Cutaneous/drug therapy , Artemisia annua/chemistry , Antiprotozoal Agents/therapeutic use , Antiprotozoal Agents/pharmacology , Cricetinae , Treatment Outcome , Plant Leaves/chemistry , Parasitic Sensitivity Tests , Leishmania/drug effects
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