The aim of this study was to evaluate the in vitro activity of furvina against microorganisms isolated from the skin of canines with piodermatitis in of Santa Clara, Cuba. Resistance to antibacterial agents was assessed by the diffusion method in agar and the in vitro activity was evaluated quantitatively by the broth macrodilution method according to international clinical laboratory standards. Fifty multiresistant strains were identified, 47 from the genus Staphylococcus and 3 from Pseudomonas. The Fisher’s exact test showed highly significant sensibility of microorganisms of the genus Staphylococcus to ciprofloxacin. All strains were resistant to at least three antimicrobials. The Minimum Inhibitory Concentration (MIC) for furvina ranged from 2-16 mg/ml where 83.2% of the strains having a MIC of 4-8 mg/mL. The Minimum Bactericidal Concentration (MBC) ranged from 4-32 mg/ml where 86.2% of the isolates oscillating between 8 and 16 mg/ml. All strains showed a MIC50 against furvina of 5.59 µg/ml (4.70-6.48) and a MBC50 of 11.8 µg/ml (10.0-13.6). These results may infer that furvina exhibits an in vitro bactericidal activity against sensitive and resistant bacteria from canine skin lesions

El objetivo del presente fue evaluar la actividad in vitro de la furvina frente a microorganismos aislados de la piel de caninos con piodermitis de la ciudad de Santa Clara, Cuba. La resistencia a los agentes antibacterianos se determinó mediante el método de difusión en agar y la actividad in vitro se evaluó cuantitativamente mediante macrodilución en caldo según procedimientos internacionales. Se identificaron 50 cepas multirresistentes, siendo 47 del género Staphylococcus y 3 del género Pseudomonas. El test exacto de Fisher demostró sensibilidad altamente significativa de los microorganismos del género Staphylococcus para la ciprofloxacina. Todas las cepas fueron resistentes al menos a tres de los antibacterianos enfrentados. Las muestras evaluadas mostraron una Concentración Inhibitoria Mínima (CIM) entre 2-16 mg/ml frente a furvina, destacándose que el 83.2% de las cepas osciló entre 4 y 8 g/ml, y una Concentración Bactericida Mínima (CBM) entre 4-32 mg/ml, resaltando que el 86.2% de los aislados osciló entre 8 y 16 mg/ml. Todas las cepas evaluadas mostraron una CIM50 frente a furvina de 5.59 mg/ml (4.70-6.48) y una CBM50 de 11.8 mg/ml (10.0-13.6). Los resultados permiten inferir que furvina posee una actividad bactericida in vitro frente a las cepas sensibles y resistentes, aisladas de lesiones en la piel de caninos

Despite recent advances in the treatment of some forms of leishmaniasis, the available drugs are still far from ideal due to inefficacy, parasite resistance, toxicity and cost. The wide-spectrum antimicrobial activity of 2-nitrovinylfuran compounds has been described, as has their activity against Trichomonas vaginalis and other protozoa. Thus, the aim of this study was to test the antileishmanial activities of six 2-nitrovinylfurans in vitro and in a murine model of leishmaniasis. Minimum parasiticide concentration (MPC) and 50% inhibitory concentration (IC50) values for these compounds against the promastigotes of Leishmania amazonensis, Leishmania infantum and Leishmania braziliensis were determined, as were the efficacies of two selected compounds in an experimental model of cutaneous leishmaniasis (CL) caused by L. amazonensis in BALB/c mice. All of the compounds were active against the promastigotes of the three Leishmania species tested. IC50 and MPC values were in the ranges of 0.8-4.7 µM and 1.7-32 µM, respectively. The compounds 2-bromo-5-(2-bromo-2-nitrovinyl)-furan (furvina) and 2-bromo-5-(2-methyl-2-nitrovinyl)-furan (UC245) also reduced lesion growth in vivo at a magnitude comparable to or higher than that achieved by amphotericin B treatment. The results demonstrate the potential of this class of compounds as antileishmanial agents and support the clinical testing of Dermofural(r) (a furvina-containing antifungal ointment) for the treatment of CL.

It was demonstrated that there is a relation of cell concentration with the parasite reading in an ELISA reader. It was determined that absorbance showed significant values in wavelengths of visible range and the possible minimum wavelength (450 nm)was chosen to guarantee the maximum sensitivity. Likewise, it was confirmed that absorbance significantly increased (p<0.001) after the plate was filled up, it stabilized in the 40m-2h time interval when applying 100, 150, 200 or 300 ml per well of the various cell concentrations, it was proved that the optimum volume was 150 ml, a r2= 0,9986 was reached, and the coefficient of correction(p<0,001) and the gradient(p<0,001)were highly significant. In the 5 x 104 to 1.5 x 107 cell/mL interval, there was an average variation coefficient of 1.75% (0.25-3.17%). Under these conditions, the quantification limit was 5,14 x 104 cell/mL. Finally, it was shown that the correlation of counting in Neubauer chamber and optical density was significant.

Se demostró que existe relación entre la concentración celular y la lectura de los parásitos en un lector de ELISA. Se determinó que la absorbancia tiene valores significativos en las longitudes de onda del rango visible y se escogió la longitud de onda mínima posible (450 nm) para garantizar un máximo de sensibilidad. Pudo comprobarse que ocurre un aumento significativo de la absorbancia (p<0,001) después de llenada la placa, que se estabiliza en el intervalo de 40 min hasta 4 h. Al aplicar 100, 150, 200 ó 300 µL por pozo de las diferentes concentraciones de células se demostró que el volumen óptimo era de 150 µL, se obtuvo un r2 = 0,9986, y resultaron altamente significativos el coeficiente de correlación (p<0,001) y la pendiente (p<0,001). En el intervalo de 5 x 104 a 1,5 x 107 células/mL se obtuvo un coeficiente de variación medio de 1,75 % (0,25-3,17 %). En estas condiciones el límite de cuantificación fue de 5,14 x 104 células/mL. Por último se demostró que hubo significación de la correlación entre el conteo en cámara de Neubauer y la densidad óptica.