Trichophyton benhamiae, un dermatofito zoofílico emergente en Argentina con reservorio en cobayos: descripción de 7 casos en un hospital de la Ciudad Autónoma de Buenos Aires / Trichophyton benhamiae, an emergent zoonotic pathogen in Argentina associated with Guinea pigs: Description of 7 cases in Buenos Aires

Resumen Trichophyton benhamiae es un dermatofito zoofílico. Puede causar tinea corporis, tinea faciei y tinea capitis. Se caracteriza por producir lesiones inflamatorias, sobre todo en niños. El objetivo de esta publicación es describir 7 casos clínicos de pacientes pediátricos atendidos entre julio del 2019 y enero del 2020 en nuestra institución. A los pacientes se les solicitó estudio micológico convencional, con posterior confirmación con MALDI-TOF MS y secuencia-ción del ADN ribosomal. Se aisló e identificó T. benhamiae como agente etiológico; el nexo epidemiológico fue el contacto con cobayos. Estas son las primeras descripciones de infecciones causadas por T. benhamiae en Argentina. Al realizar estudios micológicos convencionales, este agente puede confundirse con otros dermatofitos, por lo tanto, se requieren herramientas como MALDI-TOF MS o la secuenciación para llegar a un diagnóstico definitivo. Es importante contar con datos epidemiológicos, como el contacto con mascotas no tradicionales, para una presunción diagnóstica adecuada.

Trichophyton benhamiae is a zoonotic dermatophyte that can cause tinea corporis, tinea faciei and tinea capitis, producing inflammatory lesions, especially in children. In this publication, we describe 7clinical cases of pediatric patients that occurred in our institution between July 2019 and January 2020. All patients underwent a conventional mycological study. The identification of fungi isolates was confirmed by MALDI-TOF MS and sequencing of the ribosomal DNA. T. benhamiae was identified as the etiological agent, whose epidemiological link in all cases was the contact with Guinea pigs. This is the first description of infections caused by T. benhamiae in Argentina. This dermatophyte can be misidentified as other more frequent dermatophytes when performing conventional studies. Molecular technology should be used to reach a definitive diagnosis. It is important to have epidemiological data from patients such as contact with non-traditional pets, especially Guinea pigs, for an adequate presumptive diagnosis of this dermatophytosis.

[Trichophyton benhamiae, an emergent zoonotic pathogen in Argentina associated with Guinea pigs: Description of 7cases in Buenos Aires]. / Trichophyton benhamiae, un dermatofito zoofílico emergente en Argentina con reservorio en cobayos: descripción de 7 casos en un hospital de la Ciudad Autónoma de Buenos Aires.

Trichophyton benhamiae is a zoonotic dermatophyte that can cause tinea corporis, tinea faciei and tinea capitis, producing inflammatory lesions, especially in children. In this publication, we describe 7clinical cases of pediatric patients that occurred in our institution between July 2019 and January 2020. All patients underwent a conventional mycological study. The identification of fungi isolates was confirmed by MALDI-TOF MS and sequencing of the ribosomal DNA. T. benhamiae was identified as the etiological agent, whose epidemiological link in all cases was the contact with Guinea pigs. This is the first description of infections caused by T. benhamiae in Argentina. This dermatophyte can be misidentified as other more frequent dermatophytes when performing conventional studies. Molecular technology should be used to reach a definitive diagnosis. It is important to have epidemiological data from patients such as contact with non-traditional pets, especially Guinea pigs, for an adequate presumptive diagnosis of this dermatophytosis.

Addition of brewer's yeast Saccharomyces cerevisiae on the productive behavior and intestinal quality of guinea pigs / Adición de levadura de cerveza Saccharomyces cerevisiae sobre el comportamiento productivo y calidad intestinal de los cobayos / Adição de levedura de cerveja Saccharomyces cerevisiae sobre o comportamento produtivo e a qualidade intestinal das cobaias

Abstract The following study evaluated the effect of the addition of Saccharomyces cerevisiae over the productive parameters and intestinal quality of the guinea pigs, for a period of two months, 120 animals from 21 days old were used, distributed in three treatments TO (Testigo), T1 (2 kg S. cerevisiae/ton of feed), and T2 (4 kg S. cerevisiae/ton of feed) with four repetitions, including 10 guinea pigs per repetition. The studied variables were productive parameters and intestinal morphometry with indicators from measurements in height, width and number of intestinal villi; depth, width and number of Lieberkühn crypts; length of the crypt-villus axis and the thickness of the intestinal wall, obtaining samples of duodenum jejunum and ileum. The results determined that the addition of S. cerevisiae in the diet of guinea pigs does not significantly modify the productive parameters; however, a numerical difference was evidenced, being the T2 treatment (4 kg of S.cerevisiae / tonne of food) who recorded the highest weight gain with 766.3 gr and a feed conversion of 6.05; Regarding intestinal morphometry, Treatment T2 was able to demonstrate significant statistical difference (p<0,05) in the length of the crypt-villus axis, width of the ileum villi and thickness of the intestinal wall of guinea pigs under experiment.lt is concluded that the addition of S. cerevisiae in the feeding of guinea pigs does not exert favorable effects on the productive parameters, while in intestinal morphometry positive results are observed on the ileum.

Resumen El presente estudio evaluó el efecto de la adición de Saccharomyces cerevisiae sobre los parámetros productivos y calidad intestinal de los cobayos, por un lapso de dos meses; para ello se utilizó 120 animales de 21 días de edad, distribuidos en tres tratamientos T0 (Testigo), T1 (2 kg S. cerevisiae/tonelada de alimento) y T2 (4 kg S. cerevisiae/tonelada de alimento), con cuatro repeticiones, incluyendo 10 cobayos por replica. Las variables estudiadas fueron parámetros productivos y morfometría intestinal con indicadores de medidas en altura, ancho y número de vellosidades intestinales; profundidad, ancho y número de criptas de Lieberkühn; longitud del eje cripta-vellosidad y el grosor de la pared intestinal, obteniendo muestras de duodeno yeyuno e íleon. Los resultados determinaron que la adición de S. cerevisiae en la dieta de cuyes no modifica significativamente los parámetros productivos; sin embargo se evidencio diferencia numérica, siendo el tratamiento T2 (4 kg de S. cerevisiae/tonelada de alimento) quien registro la mayor ganancia de peso con 766,3 gr y una conversión alimenticia de 6.05; referente a morfometría intestinal el Tratamiento T2 logro demostrar diferencia estadística significativa (p<0,05) en la longitud del eje cripta-vellosidad, ancho de vellosidad del íleon y grosor de la pared intestinal de los cobayos bajo experimento. Se concluye que la adición de S. cerevisiae en la alimentación de cobayos no ejerce efectos favorables sobre los parámetros productivos, mientras que en morfometría intestinal se aprecia resultados positivos sobre el ileón.

Resumo O presente estudo avalia o efeito da ingestão de Saccharomyces cerevisiae sobre os parâmetros produtivos e de qualidade intestinal dos cobaias, por um periodo de dois meses; para ello se utilizou 120 animais de 21 días de idade distribuidos em tres tratamientos T0 (Testigo), T1 (2 kg de S. Cerevisiae / tonelada de alimento) e T2 (4 kg de S. cerevisiae/tonelada de alimento), com quatro repetições, incluindo 10 cobaias por réplica. As variáveis estudadas determinam parâmetros e morfometría intestinal com indicadores de altura, ancho e número de vellosidades intestinales; profundidad, ancho y número de criptas de Lieberkühn; longitude del eje cripta-vellosidad y el grosor de la pared intestinal, obteniendo muestras de duodeno yeyuno e ileon. Os resultados determinaram que a adição de S. cerevisiae na dieta de cobaias não modifica significativamente os parâmetros produtivos; entretanto, a diferença numérica foi evidenciada, sendo o tratamento T2 (4 kg de S. Cerevisiae / tonelada de alimento) que registrou o maior ganho de peso com 766,3 gr e uma conversão alimentar de 6,05; Em relação à morfometria intestinal, o Tratamento T2 foi capaz de demonstrar diferença estatística significante (p<0,05) no comprimento do eixo cripta-vilosidade, largura do íleo e espessura da parede intestinal das cobaias em experimento. Conclui-se que a adição de S. cerevisiae na alimentação de cobaias não exerce efeitos favoráveis sobre os parâmetros produtivos, enquanto na morfometria intestinal são observados resultados positivos no íleo.

Evaluación de una Vacuna Inactivada Oleosa del Virus de la Encefalitis Equina del Esteen Cobayos (Cavia porcellus) / Evaluation of an Oil Inactivated Vaccine of Eastern Equine Encephalitis Virus in Guinea Pigs (Cavia porcellus)

Se evaluó la inmunogenicidad y seguridad de una vacuna oleosa contra el virus de la encefalitis equina del Este, inactivada con etilenimina binaria, en tres formulaciones: Formulación I (F1): antígeno-fase oleosa; Formulación II (F2): antígeno-fase oleosa-medio de mantenimiento; Formulación III (F3): antígeno-fase oleosa-antígeno. Se evaluó la inmunidad durante un año (21, 30, 90, 160, 250, 305 y 365 d), utilizándose 70 cobayos (Cavia porcellus) de 3 a 4 meses de edad y 250 a 300 g de peso vivo, distribuidos al azar en 7 grupos de 10, para un total de siete tratamientos, a saber: Tratamiento 1 (T1): vacunados con una dosis de F1; Tratamiento 2 (T2): vacunados con dos dosis de F1; Tratamiento 3 (T3): vacunados con una dosis de F2; Tratamiento 4 (T4): vacunados con dos dosis de F2; Tratamiento 5 (T5): vacunados con una dosis de F3; Tratamiento 6 (T6): vacunados con dos dosis de F3; Tratamiento 7 (T7): no vacunados. Los cobayos se desafiaron a los 355 d post-vacunación vía intraperitoneal. Se detectó títulos de anticuerpos por inhibición de la hemoaglutinación (IH) ≥20 y por seroneutralización (SN) ≥40, a los 21 d post-vacunación cuando se usó una dosis. El ascenso máximo de anticuerpos por IH se observó a los 90 d, persistiendo e incrementándose en el desafío con una y dos dosis, a los 365 d post- vacunación. Formulaciones con dos dosis tuvieron mayores títulos en todos los períodos, siendo la F3 la que presentó los mayores títulos, seguida de la F2 y la F1, respectivamente (P<0,01). Los títulos de anticuerpos aumentaron después del desafío, siendo mayores en tratamientos con dos dosis (P<0,01). Los cobayos vacunados no desarrollaron enfermedad neurológica o viremia después del desafío. Se concluye que las formulaciones con una y dos dosis indujeron una respuesta de anticuerpos satisfactoria en cobayos durante un año.

The immunogenicity and safety of an oil vaccine against the eastern equine encephalitis virus, inactivated with binary ethylenimine in three formulations was evaluated: Formulation I (F1): antigen- oil phase; Formulation II (F2): antigen- oil phase-maintenance medium; and Formulation III (F3): antigen- oil phase-antigen. Seventy guinea pigs (Cavia porcellus) 3 to 4 months of age and 250 to 300 g of live weight were used to assess immunity for a year (21, 30, 90, 160, 250, 305 and 365 days). Animals were distributed at random in 7 groups of 10, for a total of seven treatments, as follows: Treatment: 1: vaccinated with one dose of F1; Treatment 2: vaccinated with two doses of F1; Treatment 3: vaccinated with one dose of F2; Treatment 4: vaccinated with two doses of F2; Treatment 5: vaccinated with one dose of F3; Treatment 6: vaccinated with two doses of F3; and Treatment 7: not vaccinated. The guinea pigs were challenged 355 days postvaccination through theintraperitoneal route. Antibodies titers were detected by hemoagglutination inhibition (HI) ≥ 20 and serum neutralization (SN) ≥40 to 21 days postvaccination with one dose. The maximum rise of antibodies with the HI was observed at 90 days, which persisted and increased in the challenge with one and two doses, 365 d postvacccination. Formulations with two doses showed the highest titers in all periods, being F3 the one which higher titles, followed by F2 and F1, respectively (P<0.01). Antibody titers increased after challenge, beinf higher with two doses. (P<0.01). Vaccinated guinea pigs did not develop neurologic disease or viremia after challenge. It is concluded that formulations with one and two doses, induced a satisfactory antibody response in guinea pigs for one year.

Effects produced by different types of laser in cornea of Guinea pigs: Identification of a laser capable of producing superficial lesions without leaving scars.

PURPOSE: Climatic droplets keratopathy (CDK) is closely associated with superficial corneal erosions and lack of protective mechanisms against the harmful effects of ultraviolet radiation (UVR) during a prolonged period of time. One of the difficulties in studying the pathogenic mechanisms involved in this human disease is the lack of an experimental animal model. In this paper, a study is conducted on the effects of 4 types of lasers at various powers and time conditions on the normal guinea pig corneas in order to select only one laser condition that reversibly injures the epithelium and superficial stroma, without leaving scarring. METHODS: Damage was induced in the cornea of Guinea pigs using different powers and exposure times of 4 types of laser: argon, CO2, diode and Nd-Yag, and any injuries were evaluated by biomicroscopy (BM) and optical microscopy. Corneas from other normal animals were exposed to argon laser (350 mW, 0.3s, 50 µm of diameter), and the induced alterations were studied at different times using BM, optical coherence tomography (OCT) and transmission electron microscopy (TEM). RESULTS: Only argon laser at 350 mW, 0.3s, 50 µm of diameter produced epithelium and superficial stroma lesions. Some leukomas were observed by BM, and they disappeared by day 15. Corneal thickness measured by OCT decreased in the eyes treated with argon laser during the first week. Using TEM, different ultra structural alterations in corneal epithelium and stroma were observed during the early days, which disappeared by day 15. CONCLUSIONS: It was possible to develop reproducible corneal epithelium and anterior stroma injuries using Argon laser at 350 mW, 0.3s, 50 µm of diameter. In vivo and in vitro studies showed that injured corneas with these laser conditions did not leave irreversible microscopic or ultra structural alterations. This protocol of corneal erosion combined with exposure to UVR and partial deficiency of ascorbate in the diets of the animals for an extended period of time has been used in order to try to develop an experimental model of CDK.

Efectos de la tintura de Melissa officinalis l. sobre íleon aislado y en modelo de diarreas / Effects of Melissa officinalis L. tincture on isolated ileum and in diarrhea model

Se realizaron 2 estudios, uno in vitro en el íleon aislado de cobayo y otro in vivo en un modelo de diarreas en ratas, con el objetivo de corroborar la acción antiespasmódica de una tintura al 20 % de Melissa officinalis L. En el modelo in vitro se encontró que las dosis de 0,084, 0,169 y 0,338 mg/mL de solución nutricia provocan una disminución significativa (p < 0,05) de la contracción inducida con acetilcolina (10 mg/mL). En el estudio in vivo se determinó que las dosis de 16,9, 33,8 y 67, 6 mg/kg de peso disminuían el tiempo de aparición de la primera diarrea y su frecuencia. En ambos modelos el efecto estuvo en dependencia de las dosis. La tintura tuvo un efecto antiespasmódico en los 2 modelos utilizados y una acción antidiarreica sobre el modelo in vivo.

Two studies were carried out: one in vitro in the guinea pig isolated ileum, and the other in vivo, in a diarrhea model in rats, with the purpose of confirming the antispasmodic action of a 20 % Melissa officinalis L. tincture. In the in vitro model, it was found that the 0,084; 0,169 and 0,338 mg/mL doses of nutritious solution provoke a significant decrease (p < 0,05) of the acetylcholine induced contraction (10 mg/mL). In the in vivo study, it was determined that 16,9; 33,8 and 67,6 mg/kg of weight doses decreased the time of appearance of the first diarrhea, and its frequency. In both models the effect was dependent on the doses. The tincture had an antispasmodic effect in the two models used, and an antidiarrheic action on the in vivo model.