Successful treatment of experimental murine vulvovaginal candidiasis with gentian violet.

Aim: This study evaluated the antifungal efficacy of gentian violet (GV) in an experimental vulvovaginal candidiasis (VVC) model. Materials & methods: In vitro susceptibility and cytotoxicity assays were performed to validate the antifungal potential and safety of GV. The antifungal efficacy was then evaluated in vivo through comparative analysis of the fungal burden following treatment with GV or nystatin, as well as assessment of the vaginal tissue by histology and electron microscopy. Results: GV demonstrated a safe antifungal profile against C. albicans, with a significant decrease in fungal burden and an improvement in the inflammatory process evaluated histologically. Conclusion: The results of this study motivate further assessment of GV as a promising alternative for VVC therapy.

Removal of Anionic and Cationic Dyes Present in Solution Using Biomass of Eichhornia crassipes as Bioadsorbent.

The discharge of large amounts of effluents contaminated with gentian violet (GV) and phenol red (PR) threatens aquatic flora and fauna as well as human health, which is why these effluents must be treated before being discarded. This study seeks the removal of dyes, using water lily (Eichhornia crassipes) as an adsorbent with different pretreatments. PR and GV were analyzed by a UV-visible spectrophotometer. Equilibrium experimental data showed that Freundlich is the best model to fit PR and SIPS for GV, showing that the adsorption process for both dyes was heterogeneous, favorable, chemical (for GV), and physical (for PR). The thermodynamic analysis for the adsorption process of both dyes depends directly on the increase in temperature and is carried out spontaneously. The Pseudo first Order (PFO) kinetic model for GV and PR is the best fit for the dyes having an adsorption capacity of 91 and 198 mg/g, respectively. The characterization of the materials demonstrated significant changes in the bands of lignin, cellulose, and hemicellulose, which indicates that the functional groups could participate in the capture of the dyes together with the electrostatic forces of the medium, from which it be concluded that the adsorption process is carried out by several mechanisms.

Formación de biopelículas por Candida parapsilosis sensu stricto y su perfil de susceptibilidad en Venezuela / Biofilm-forming of Candida parapsilosis sensu stricto and its susceptibility profile in Venezuela

Una de las principales consecuencias del desarrollo de biopelículas es la resistencia a los antifúngicos. Se determinó la formación de biopelículas por Candida parapsilosis sensu stricto aisladas de sangre y su perfil de susceptibilidad. Se evaluaron 30 cepas de C. parapsilosis sensu stricto de la Red de Candidemias del Dpto. de Micología del Instituto Nacional de Higiene Rafael Rangel-Venezuela, por el método cuantitativo en microplaca con tinción de cristal violeta y el método cualitativo en agar Sabouraud dextrosa suplementado con rojo Congo. Se utilizó el método de microdilución según el documento M-27 del Clinical and Laboratory Standards Institute. La formación de biopelículas de C. parapsilosis sensu stricto por el método cuantitativo fue de 63% y por el método cualitativo de 50%. El método cualitativo presentó valores de sensibilidad, especificidad, valores predictivos positivo y negativo de 61,1%, 23%, 78,6%, 43,8% respectivamente frente al método cuantitativo. Los aislados en forma planctónica fueron 100% sensibles a anfotericina B y caspofungina, con susceptibilidad variable a los azoles. El método cuantitativo es una técnica confiable para determinar la formación de biopelículas. El método cualitativo puede usarse como método pantalla inicial. No se encontró relación entre la susceptibilidad de las formas planctónicas y la capacidad de producción de biopelículas

One of the main consequences of biofilm development is resistance to antifungals. Biofilmforming by Candida parapsilosis sensu stricto isolated from blood and its susceptibility profile was determined. Thirty strains of C. parapsilosis sensu stricto belonging to the Candidemia Network of the Mycology Department of the Instituto Nacional de Higiene Rafael Rangel-Venezuela, were evaluated by microplate quantitative method with violet crystal staining, and Sabouraud dextrose agar supplemented with Congo red qualitative method. The microdilution method was used to determine the susceptibility, according to the Clinical and Laboratory Standards Institute M-27 document. Biofilm formation of C. parapsilosis sensu stricto by both quantitative and qualitative method was 63% and 50%, respectively. Sensitivity, specificity, and positive and negative predictive values of the qualitative method were 61.1%, 23%, 78.6%, and 43.8% respectively, when compared with quantitative method. Planktonic isolates were 100% sensitive to amphotericin B and caspofungin, with variable susceptibility to azoles. Quantitative method is a reliable assay to determine biofilm formation, while qualitative method can be used as an initial screening assay. No relationship was found between susceptibility of planktonic isolates and the ability to biofilm-forming

The topical treatment of old world cutaneous leishmaniasis with gentian violet along with cryotherapy: a pilot single-blind randomized controlled clinical trial

Abstract INTRODUCTION: The promising non-clinical antileishmanial effects of gentian violet (GV) encouraged us to evaluate the additive effect of GV on cryotherapy. METHODS: For 8 weeks, 59/161 cutaneous leishmaniasis patients/lesions underwent cryotherapy alone (group 1) or cryotherapy accompanied by 1% GV application (group 2). The primary endpoint was clinical response. RESULTS: Ultimately, 54.7% and 45.3% of the significantly cured lesions belonged to groups 1 and 2, respectively, which was not statistically significant. The clinical response was significantly different between the two groups at the end of the fourth week. CONCLUSIONS: Although the clinical response of the two groups was significantly different at the end of the fourth week, application of GV did not increase the efficacy of cryotherapy.

Enfermedad de Chagas: Contribuciones del Centro de Investigaciones Toxicológicas / Chagas disease: The contribution of the Center for Toxicological Research / Doenþa de Chagas: Contribuiþ§es do Centro de Investigaþ§es Toxicológicas

La quimioterapia de la enfermedad de Chagas cuenta en la actualidad con el empleo de dos fármacos solamente: Nifurtimox y Benznidazol. Nifurtimox es un nitrofurano y Benznidazol es un compuesto nitroimidazólico. El uso de estas drogas para tratar la fase aguda de la enfermedad se acepta ampliamente. Sin embargo, su utilización en el tratamiento de la fase crónica no está exenta de cuestionamientos serios. Los efectos colaterales de ambas son un inconveniente mayor en su uso, y frecuentemente fuerza a los médicos a detener el tratamiento. Los estudios de toxicidad experimentales con Nifurtimox evidenciaron neurotoxicidad, daño testicular, toxicidad ovárica y efectos deletéreos en corazón, tejido mamario, adrenales, colon y esófago. Para el Benznidazol, se observaron efectos deletéreos en adrenales, colon y esófago. También inhibe el metabolismo de varios xenobióticos transformados por el sistema del citocromo P450 y sus metabolitos reaccionan con los componentes fetales in vivo. Ambas drogas exhibieron efectos mutagénicos significativos y se demostró en algunos estudios que eran carcinogénicas o tumorigénicas. Los efectos tóxicos de ambos fármacos dependen de la reducción enzimática de su grupo nitro. En este trabajo se resume la actividad de este laboratorio en el esfuerzo por comprender los mecanismos de la acción tóxica de estos fármacos.(AU)

Chemotherapy of Chagas disease is currently performed by the use of only two drugs: Nifurtimox and Benznidazole. Nifurtimox is a nitrofurane and Benznidazole is a nitroimidazole compound. The use of these drugs to treat the acute phase of the disease is now widely accepted. However, their use in the treatment of the chronic phase is not without serious consequences. The side effects of both drugs are a major drawback in their use and often force physicians to stop treatment. In the case of Nifurtimox, experimental toxicity studies showed neurotoxicity, testicular damage, ovarian toxicity and deleterious effects in heart, breast tissue, adrenals, colon and esophagus. Benznidazole deleterious effects were observed in adrenals, colon and esophagus. It also inhibits the metabolism of various xenobiotics transformed by cytochrome P450 and its metabolites react with fetal components in vivo. Both drugs exhibited significant mutagenic effects and in some studies, they demonstrated to be carcinogenic or tumorigenic. Toxic effects of both drugs are dependent on the enzymatic reduction of the nitro group. This paper summarizes this laboratory’s activity in an effort to understand the mechanisms of these drugs’ toxic action.(AU)

A quimioterapia da doenþa de Chagas tem atualmente com o uso de apenas dois medicamentos: nifurtimox e benzonidazol. Nifurtimox é um nitrofuran e benzonidazol é um composto nitroimidazólico. A utilizaþÒo destes fármacos para o tratamento da fase aguda da doenþa é agora amplamente aceite. No entanto, a sua utilizaþÒo no tratamento da fase crónica nÒo é sem dúvida graves. Os efeitos colaterais de ambas sÒo uma grande desvantagem na sua utilizaþÒo, e frequentemente médicos forþa para interromper o tratamento. Estudos experimentais com Nifurtimox mostraram neurotoxicidade, lesÒo testicular, toxicidade ovariana e efeitos deletérios no coraþÒo, tecido mamário, adrenal, cólon e es¶fago. Para benzonidazole efeitos deletérios foram observadas em supra-renal, cólon e esofágica. Também inibe o metabolismo de vários xenobióticos transformadas pelo citocromo P450 e seus metabolitos reagem com componentes fetal in vivo. Ambos os fármacos apresentaram efeitos mutagÛnicos significativos demonstrado em alguns estudos que eram cancerígenas ou tumorigenic. Os efeitos tóxicos de ambas as drogas sÒo dependentes da reduþÒo enzimática do grupo nitro. Neste trabalho a atividade do nosso laboratório no esforþo para compreender os mecanismos de aþÒo tóxica dessas drogas é resumida.(AU)

Genotoxicidad en leucocitos por la quimioprofilaxis de sangre con Violeta de Genciana y su prevención con antioxidantes / Genotoxicity in leukocytes by blood chemoprophylaxis with Gentian Violet and its prevention with antioxidants / Genotoxicidade em leucócitos pela quimioprofilaxia de sangue com Violeta Genciana e sua prevenção com antioxidantes

El Violeta de Genciana (GV) se usa como aditivo en la sangre para eliminar el Trypanosoma cruzi en la quimioprofilaxis de la infección por enfermedad de Chagas vía transfusión sanguínea, cuando no es posible un control previo de laboratorio o bajo situaciones de emergencia. En estos estudios se encontraron efectos genotóxicos del GV con el ensayo Cometa, cuando se lo agregó a la sangre bajo las condiciones empleadas para esterilizarla para transfusión. El efecto genotóxico fue aún más intenso si la sangre se mantenía con GV por 48 horas. Los resultados obtenidos con el ensayo Cometa sugieren la formación de bases hidroxiladas de ADN como resultado de un ataque de especies reactivas de oxígeno y apoyan la genotoxicidad del GV y su potencial carcinogénico ya informado previamente. Los efectos genotóxicos observados en el ensayo Cometa fueron parcialmente prevenidos por administración de antioxidantes que ya tienen uso clínico seguro, como á-tocoferol, ácido lipoico o N-acetilcisteína. El ácido lipoico fue capaz también de reaccionar in vitro con GV. Los resultados sugieren un uso potencial de estos antioxidantes para prevenir los efectos secundarios no deseados del GV para el individuo receptor de la sangre.

Gentian violet (GV) is being used as blood additive to eliminate Trypanosoma cruzi in the chemoprophylaxis of Chagas disease infection via blood transfusion when prior laboratory control is not possible or under emergency circumstances in endemic areas. In these studies genotoxic effects of GV were found employing the Comet assay when GV was added to rat blood under the cisconditions employed to sterilize it for transfusion. The genotoxic effect was even more intense if blood was kept with GV for 48 hours. The positive results obtained in the Comet assay suggest the formation of DNA hydroxylated bases as result of a reactive oxygen species (ROS) attack and further confirm GV genotoxicity and its potential carcinogenic effects previously reported. Genotoxicity effects observed in the Comet assay were partially but significantly prevented by prior administration of antioxidants having safe clinical use such as á-tocopherol; lipoic acid or N-acetylcysteine. Lipoic acid was also able to chemically react in vitro with GV (eg. the one remaining in the transfusion mixture after it had enough time to eliminate the parasite from blood). Results would suggest the potential use of these antioxidants to prevent unwanted side effects of GV for the blood recipient.

O Violeta de Genciana (GV) é utilizado como aditivo no sangue para remover o Trypanosoma cruzi da sangue em quimioprofilaxia da infecção por doença de Chagas através de transfusão de sangue, quando não é possível controle prévio de laboratório ou em situações de emergência. Nestes estudos encontraram-se efeitos genotóxicos do GV utilizando o ensaio Cometa, quando o GV foi adicionado ao sangue sob as condições utilizadas para a esterilização para transfusão. O efeito genotóxico foi ainda mais intenso se o sangue era mantido durante 48 horas com GV. Os resultados obtidos com o ensaio Cometa sugerem a formação de bases de DNA hidroxiladas, como resultado de um ataque de espécies reativas de oxigênio e apoiam a genotoxicidade do GV e seu potencial carcinogênico já informado anteriormente. Efeitos genotóxicos observados no ensaio do Cometa foram parcialmente prevenidos por administração de antioxidantes que já têm uso clínico seguro, como á-tocoferol, o ácido lipoico ou N-acetilcisteína. O ácido lipoico também foi capaz de reagir in vitro com GV. Os resultados sugerem um uso potencial destes antioxidantes para prevenir os efeitos colaterais não desejados de GV para o indivíduo receptor do sangue.

Genotoxicidad en leucocitos por la quimioprofilaxis de sangre con Violeta de Genciana y su prevención con antioxidantes / Genotoxicity in leukocytes by blood chemoprophylaxis with Gentian Violet and its prevention with antioxidants / Genotoxicidade em leucócitos pela quimioprofilaxia de sangue com Violeta Genciana e sua prevenþÒo com antioxidantes

El Violeta de Genciana (GV) se usa como aditivo en la sangre para eliminar el Trypanosoma cruzi en la quimioprofilaxis de la infección por enfermedad de Chagas vía transfusión sanguínea, cuando no es posible un control previo de laboratorio o bajo situaciones de emergencia. En estos estudios se encontraron efectos genotóxicos del GV con el ensayo Cometa, cuando se lo agregó a la sangre bajo las condiciones empleadas para esterilizarla para transfusión. El efecto genotóxico fue aún más intenso si la sangre se mantenía con GV por 48 horas. Los resultados obtenidos con el ensayo Cometa sugieren la formación de bases hidroxiladas de ADN como resultado de un ataque de especies reactivas de oxígeno y apoyan la genotoxicidad del GV y su potencial carcinogénico ya informado previamente. Los efectos genotóxicos observados en el ensayo Cometa fueron parcialmente prevenidos por administración de antioxidantes que ya tienen uso clínico seguro, como á-tocoferol, ácido lipoico o N-acetilcisteína. El ácido lipoico fue capaz también de reaccionar in vitro con GV. Los resultados sugieren un uso potencial de estos antioxidantes para prevenir los efectos secundarios no deseados del GV para el individuo receptor de la sangre.(AU)

Gentian violet (GV) is being used as blood additive to eliminate Trypanosoma cruzi in the chemoprophylaxis of Chagas disease infection via blood transfusion when prior laboratory control is not possible or under emergency circumstances in endemic areas. In these studies genotoxic effects of GV were found employing the Comet assay when GV was added to rat blood under the cisconditions employed to sterilize it for transfusion. The genotoxic effect was even more intense if blood was kept with GV for 48 hours. The positive results obtained in the Comet assay suggest the formation of DNA hydroxylated bases as result of a reactive oxygen species (ROS) attack and further confirm GV genotoxicity and its potential carcinogenic effects previously reported. Genotoxicity effects observed in the Comet assay were partially but significantly prevented by prior administration of antioxidants having safe clinical use such as á-tocopherol; lipoic acid or N-acetylcysteine. Lipoic acid was also able to chemically react in vitro with GV (eg. the one remaining in the transfusion mixture after it had enough time to eliminate the parasite from blood). Results would suggest the potential use of these antioxidants to prevent unwanted side effects of GV for the blood recipient.(AU)

O Violeta de Genciana (GV) é utilizado como aditivo no sangue para remover o Trypanosoma cruzi da sangue em quimioprofilaxia da infecþÒo por doenþa de Chagas através de transfusÒo de sangue, quando nÒo é possível controle prévio de laboratório ou em situaþ§es de emergÛncia. Nestes estudos encontraram-se efeitos genotóxicos do GV utilizando o ensaio Cometa, quando o GV foi adicionado ao sangue sob as condiþ§es utilizadas para a esterilizaþÒo para transfusÒo. O efeito genotóxico foi ainda mais intenso se o sangue era mantido durante 48 horas com GV. Os resultados obtidos com o ensaio Cometa sugerem a formaþÒo de bases de DNA hidroxiladas, como resultado de um ataque de espécies reativas de oxigÛnio e apoiam a genotoxicidade do GV e seu potencial carcinogÛnico já informado anteriormente. Efeitos genotóxicos observados no ensaio do Cometa foram parcialmente prevenidos por administraþÒo de antioxidantes que já tÛm uso clínico seguro, como á-tocoferol, o ácido lipoico ou N-acetilcisteína. O ácido lipoico também foi capaz de reagir in vitro com GV. Os resultados sugerem um uso potencial destes antioxidantes para prevenir os efeitos colaterais nÒo desejados de GV para o indivíduo receptor do sangue.(AU)