RESUMEN
Mycotoxins are responsible for economic losses in the swine production industry, especially during post-weaning, when piglets are physiologically immature. Spray-dried porcine plasma (SDPP), added to pig diets, may help reduce losses due to mycotoxins. This work investigates the effects of SDPP in post-weaning piglets fed with diets containing natural contaminants or with more contaminants (co-contamination by mycotoxins). Fifty-six castrated weaned piglets were used in a randomized 2 (0 and 6% of SDPP) x 2 (natural contamination or co-contamination with mycotoxin) factorial design, with seven experimental units of two piglets each. The natural contaminants were 0.95 µg/kg aflatoxins +450 µg/kg fumonisins. The co-contaminated diet contained 300 µg/kg aflatoxins +8000 µg/kg fumonisins. Animals were fed 15 days with experimental diets. Feed intake, weight gain, feed efficiency, diarrhea incidence, and economic feasibility of SDPP treatement were evaluated in three periods of five days each. There was no interaction (Pâ¯<â¯0.05) between mycotoxins levels and SDPP. Feed intake, weight gain and feed efficiency were higher (Pâ¯<â¯0.05) in diets supplemented with SDPP. Animals fed with SDPP showed lower (Pâ¯<â¯0.05) diarrhea incidence in the 1-10 day and 1-15 day periods. The experimental dose of mycotoxins reduced (Pâ¯<â¯0.05) weight gain at 11-15 days. SDPP proved to be economical feasible over the total experimental period (1-15 days). Spray-dried plasma improved weight gain, feed intake and reduced diarrhea incidence in piglets post-weaning, but did not correlate with various levels of mycotoxins.
Asunto(s)
Alimentación Animal , Proteínas Sanguíneas/uso terapéutico , Diarrea/prevención & control , Suplementos Dietéticos , Micotoxinas/toxicidad , Porcinos/crecimiento & desarrollo , Destete , Aumento de Peso , Aflatoxinas/efectos adversos , Aflatoxinas/toxicidad , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Costos y Análisis de Costo , Dieta/veterinaria , Modelos Animales de Enfermedad , Contaminación de Alimentos , Hongos/metabolismo , Incidencia , Masculino , Plasma , Porcinos/sangre , Porcinos/fisiología , Factores de TiempoRESUMEN
Pythium insidiosum is an important aquatic oomycete which can cause pythiosis in both animals and humans. This microorganism shows low susceptibility to antifungal drugs available. This study analyzed the in vitro antimicrobial activity of Melaleuca alternifolia in its free oil (FO) and nanoemulsion (NE) formulations against Brazilian P. insidiosum isolates. The antimicrobial activity evaluation was performed by the broth microdilution method according to CSLI M38-A2 document adapted to phytopharmaceuticals. Twenty-six P. insidiosum isolates were evaluated, and the minimum inhibitory concentration was determined at 100 % growth inhibition. Melaleuca alternifolia essential oil or FO was obtained commercially. The NE containing 1 % M. alternifolia essential oil was prepared by the spontaneous emulsification method. All P. insidiosum isolates evaluated showed minimum inhibitory concentrations (MIC) ranging from 531.5 to 2125 µg/mL for the FO formulation; MIC50 and MIC90 showed values between 1062.5 and 2125 µg/mL, respectively. When the NE formulation was evaluated, MIC values ranged from 132.7 to 2125 µg/mL and both MIC50 and MIC90 corresponded to 1062.5 µg/mL. FO and NE formulations of M. alternifolia showed antimicrobial activity against P. insidiosum. This study demonstrated that M. alternifolia oil can be an additional therapy in pythiosis treatment; however, further studies are needed to evaluate the applicability of the plant essential oils in the treatment of clinical pythiosis.
Asunto(s)
Antifúngicos/farmacología , Emulsiones/farmacología , Melaleuca/química , Aceites Volátiles/farmacología , Pythium/efectos de los fármacos , Antifúngicos/aislamiento & purificación , Brasil , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/aislamiento & purificación , Pythium/aislamiento & purificaciónRESUMEN
We evaluated the combination of posaconazole with amphotericin B in vitro and in a murine model of systemic infections caused by Sporothrix brasiliensis and Sporothrix schenckii sensu stricto. In vitro data demonstrated a synergistic effect, and although posaconazole alone was effective against sporotrichosis, efficacy in terms of survival and burden reduction was increased with the combination. This combination might be an option against disseminated sporotrichosis, especially when itraconazole or amphotericin B at optimal doses are contraindicated.
Asunto(s)
Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Sporothrix/efectos de los fármacos , Esporotricosis/tratamiento farmacológico , Triazoles/uso terapéutico , Animales , Farmacorresistencia Fúngica Múltiple , Quimioterapia Combinada , Ratones , Pruebas de Sensibilidad Microbiana , Sporothrix/patogenicidadRESUMEN
Here, we evaluated combinations of diphenyl diselenide [(PhSe)2] with fluconazole and amphotericin B in a checkerboard assay against clinical Candida glabrata strains. Minimal inhibitory concentration (geometric mean) ranged from 0.25 to >64 (5.16 µg/mL) for (PhSe)2, 1 to 32 (5.04 µg/mL) for fluconazole and 0.06 to 0.5 (0.18 µg/mL) for amphotericin B. Synergistic (76.66 %) and indifferent (23.34 %) interactions were observed for (PhSe)2 + amphotericin B combination. (PhSe)2 + fluconazole combination demonstrated indifferent (50 %) and antagonistic (40 %) interactions, whereas synergistic interactions were observed in 10 % of the isolates. New experimental in vivo protocols are necessary and will promote a better understanding of the antimicrobial activity of (PhSe)2 against C. glabrata and its use as an adjuvant therapy with antifungal agents.
Asunto(s)
Anfotericina B/farmacología , Antifúngicos/farmacología , Derivados del Benceno/farmacología , Candida glabrata/efectos de los fármacos , Fluconazol/farmacología , Compuestos de Organoselenio/farmacología , Interacciones Farmacológicas , Pruebas de Sensibilidad MicrobianaRESUMEN
Here, a microdilution technique based on the M27-A2 protocol (NCCLS, 2002) was employed to compare the susceptibilities of Candida albicans and Candida dubliniensis to essential oils extracted from plants used as spices. The chemical compositions of the essential oils were defined based on the analysis of retention indices obtained by gas chromatography-mass spectroscopy. Taken together, the results showed that the activity of the compounds against the two species was similar.
Asunto(s)
Antifúngicos/farmacología , Candida/efectos de los fármacos , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Extractos Vegetales/químicaRESUMEN
In the present study, the antifungal activity of selected essential oils obtained from plants used as spices was evaluated against both fluconazole-resistant and fluconazole-susceptible Candida spp. The Candida species studied were Candida albicans, Candida dubliniensis, Candida tropicalis, Candida glabrata, and Candida krusei. For comparison purposes, they were arranged in groups as C. albicans, C. dubliniensis, and Candida non-albicans. The essential oils were obtained from Cinnamomum zeylanicum Breyn, Lippia graveolens HBK, Ocimum basilicum L., Origanum vulgare L., Rosmarinus officinalis L., Salvia officinalis L., Thymus vulgaris L., and Zingiber officinale. The susceptibility tests were based on the M27-A2 methodology. The chemical composition of the essential oils was obtained by gas chromatography-mass spectroscopy and by retention indices. The results showed that cinnamon, Mexican oregano, oregano, thyme, and ginger essential oils have different levels of antifungal activity. Oregano and ginger essential oils were found to be the most and the least efficient, respectively. The main finding was that the susceptibilities of fluconazole-resistant C. albicans, C. dubliniensis, and Candida non-albicans to Mexican oregano, oregano, thyme, and ginger essential oils were higher than those of the fluconazole-susceptible yeasts (P<0.05). In contrast, fluconazole-resistant C. albicans and Candida non-albicans were less susceptible to cinnamon essential oil than their fluconazole-susceptible counterparts (P<0.05). A relationship between the yeasts' susceptibilities and the chemical composition of the essential oils studied was apparent when these 2 parameters were compared. Finally, basil, rosemary, and sage essential oils did not show antifungal activity against Candida isolates at the tested concentrations.
Asunto(s)
Antifúngicos/farmacología , Candida/efectos de los fármacos , Farmacorresistencia Fúngica , Fluconazol/farmacología , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Antifúngicos/química , Candidiasis/microbiología , Humanos , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Aceites de Plantas/química , Especias/análisisRESUMEN
O Pythium insidiosum é um fungo zoospórico que se desenvolve em locais alagadiços e que pode infectar humanos e animais, principalmente eqüinos. A infecçäo natural nesta espécie resulta em pitiose clínica, uma doença granulomatosa de difícil tratamento. Uma das opçöes terapêuticas é a imunoterapia com antígenos obtidos de culturas do agente. Com o objetivo de avaliar o efeito de adjuvantes na resposta sorológica a antígenos do P. insidiosum, 24 coelhos divididos em 4 grupos foram imunizados com antígeno macerado de micélio (AMM) associado a três adjuvantes. Grupo I: hidróxido de alumínio; grupo II: adjuvante de Freund; grupo III: óleo mineral e grupo IV: água destilada -controle. Os tratamentos foram avaliados a diferentes intervalos, quanto à capacidade de induzir a produçäo de imunoglobulinas específicas da classe G, através da técnica de ELISA. Na fase 1, os animais receberam três doses do imunógeno (dias zero, 14 e 28) e foram avaliados sorologicamente nos dias 14, 21, 28 e 35. Nessa fase, os adjuvantes oleosos (GII e III) induziram níveis de anticorpos estatisticamente superiores aos induzidos nos grupos I e IV. Durante a fase 2 (dias 42 a 120), cada grupo foi subdividido em dois; sendo um subgrupo mantido em tratamento (imunizaçöes adicionais nos dias 42, 56, 68 e 82) e o outro tendo o tratamento interrompido após a 3ª dose (dia 28). Nos subgrupos mantidos em tratamento, os níveis de anticorpos dos grupos imunizados com adjuvantes foram estatisticamente superiores aos induzidos no grupo GIV (controle). Nos coelhos com tratamento interrompido, os grupos I, II e III apresentaram manutençäo nos níveis de IgG e foram estatisticamente superiores ao grupo controle, que apresentou declínio nos níveis de anticorpos. Os resultados demonstraram a capacidade dos adjuvantes testados em potencializar e prolongar a resposta humoral aos antígenos do P. insidiosum. O uso de adjuvantes associado aos atuais imunógenos pode aumentar os índices de cura em eqüinos submetidos à imunoterapia, assim como viabilizar sua utilizaçäo como preventivo