García Sánchez, Marta Eulalia

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First Name
Marta Eulalia
Last Name
García Sánchez
Universidad Complutense de Madrid
Faculty / Institute
Sanidad Animal
Sanidad Animal
UCM identifierScopus Author IDDialnet IDGoogle Scholar ID

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Now showing 1 - 10 of 11
  • Publication
    NcGRA7 and NcROP40 Play a Role in the Virulence of Neospora caninum in a Pregnant Mouse Model
    (MPDI, 2022-08-31) Rico San Román, Laura; Amieva, Rafael; Regidor Cerrillo, Javier; García Sánchez, Marta Eulalia; Collantes Fernández, Esther; Pastor Fernández, Iván; Saeij, Jeroen P. J.; Ortega Mora, Luis Miguel; Horcajo, Pilar
    The intraspecific variability among Neospora caninum isolates in their in vitro behaviour and in vivo virulence has been widely studied. In particular, transcriptomic and proteomic analyses have shown a higher expression/abundance of specific genes/proteins in high-virulence isolates. Consequently, the dense granule protein NcGRA7 and the rhoptry protein NcROP40 were proposed as potential virulence factors. The objective of this study was to characterize the role of these proteins using CRISPR/Cas9 knockout (KO) parasites in a well-established pregnant BALB/c mouse model of N. caninum infection at midgestation. The deletion of NcGRA7 and NcROP40 was associated with a reduction of virulence, as infected dams displayed milder clinical signs, lower parasite burdens in the brain, and reduced mortality rates compared to those infected with the wild-type parasite (Nc-Spain7). Specifically, those infected with the NcGRA7 KO parasites displayed significantly milder clinical signs and a lower brain parasite burden. The median survival time of the pups from dams infected with the two KO parasites was significantly increased, but differences in neonatal mortality rates were not detected. Overall, the present study indicates that the disruption of NcGRA7 considerably impairs virulence in mice, while the impact of NcROP40 deletion was more modest. Further research is needed to understand the role of these virulence factors during N. caninum infection.
  • Publication
    Elaboración de una guía online de antifúngicos y resistencias antifúngicas en Veterinaria
    (2022) Álvarez Pérez, Sergio; Anega de Alvarado, Blanca; Tercero Guerrero, Daniela Vanessa; García Sánchez, Marta Eulalia; Blanco Cancelo, José Luis
    La rápida aparición a nivel mundial de resistencias a los fármacos antifúngicos representa una gran amenaza para la salud humana y animal, así como para la seguridad alimentaria. Sin embargo, existe aún muy poca conciencia pública sobre la relevancia de la resistencia a los antifúngicos en medicina veterinaria, lo cual contrasta con el gran interés que despiertan las bacterias resistentes a antibióticos. Entre los principales factores responsables del menor interés por el estudio de las resistencias antifúngicas en medicina animal suele destacarse la escasa importancia que se concede en veterinaria a los procesos infecciosos de etiología fúngica. Mediante el presente Proyecto de Innovación Educativa nos propusimos crear una “Guía Online de Antifúngicos y Resistencias Antifúngicas en Veterinaria” de acceso gratuito y 100% online, que incluya información relevante y material gráfico sobre los antifúngicos utilizados actualmente en medicina veterinaria, las técnicas aplicadas al estudio de los perfiles de sensibilidad antifúngica y los principales mecanismos de resistencia antifúngica observados en aislamientos de hongos filamentosos y levaduras de origen animal. Se pretende así que los estudiantes del Grado en Veterinaria, del Diploma en Asistencia Técnica en Clínica Veterinaria y otras titulaciones afines vayan adquiriendo conocimientos sobre Micología Clínica que les serán de gran utilidad durante sus estudios y, posteriormente, en su acceso a la vida profesional en un contexto de escasez de expertos en Micología Veterinaria.
  • Publication
    Creación de un Atlas online de Micología Clínica Veterinaria
    (2021-06-11) García Sánchez, Marta Eulalia; Anega de Alvarado, Blanca; Álvarez Pérez, Sergio; Blanco Cancelo, José Luis
    Pese a la creciente importancia de los hongos en patología animal, la información existente sobre la prevalencia de la mayoría de micosis animales es aún muy limitada y, en algunos casos, incluso la etiología de la infección sigue sin estar clara. Entre los principales factores responsables de esta falta de información sobre la importancia de las micosis en medicina animal suele destacarse la escasa formación micológica de los profesionales veterinarios. Mediante el presente “Atlas de Micología Clínica Veterinaria”, de acceso gratuito y 100% online, pretendemos que los estudiantes de Veterinaria y otras titulaciones afines vayan adquiriendo conocimientos básicos sobre los principales hongos filamentosos, levaduras y microalgas de importancia clínica en medicina animal. El Atlas está optimizado para ser visualizado tanto en pantallas de ordenadores personales como en dispositivos móviles.
  • Publication
    In vitro activity of fidaxomicin and combinations of fidaxomicin with other antibiotics against Clostridium perfringens strains isolated from dogs and cats
    (BMC, 2023-11-16) Álvarez Pérez, Sergio; Anega, Blanca; Blanco Cancelo, José Luis; Hernandez, Marta; García Sánchez, Marta Eulalia
    Background: Previous studies have demonstrated that fidaxomicin, a macrocyclic lactone antibiotic used to treat recurrent Clostridioides difficile-associated diarrhea, also displays potent in vitro bactericidal activity against Clostridium perfringens strains isolated from humans. However, to date, there is no data on the susceptibility to fidaxomicin of C. perfringens strains of animal origin. On the other hand, although combination therapy has become popular in human and veterinary medicine, limited data are available on the effects of antibiotic combinations on C. perfringens. We studied the in vitro response of 21 C. perfringens strains obtained from dogs and cats to fidaxomicin and combinations of fidaxomicin with six other antibiotics. Results: When tested by an agar dilution method, fidaxomicin minimum inhibitory concentrations (MICs) ranged between 0.004 and 0.032 μg/ml. Moreover, the results of Etest-based combination assays revealed that the incorporation of fidaxomicin into the test medium at a concentration equivalent to half the MIC significantly increased the susceptibility of isolates to metronidazole and erythromycin in 71.4% and 61.9% of the strains, respectively, and the susceptibility to clindamycin, imipenem, levofloxacin, and vancomycin in 42.9–52.4% of the strains. In contrast, ¼ × MIC concentrations of fidaxomicin did not have any effect on levofloxacin and vancomycin MICs and only enhanced the effects of clindamycin, erythromycin, imipenem, and metronidazole in ≤ 23.8% of the tested strains. Conclusions: The results of this study demonstrate that fidaxomicin is highly effective against C. perfringens strains of canine and feline origin. Although fidaxomicin is currently considered a critically important antimicrobial that has not yet been licensed for veterinary use, we consider that the results reported in this paper provide useful baseline data to track the possible emergence of fidaxomicin resistant strains of C. perfringens in the veterinary setting.
  • Publication
    Characterization of Neospora caninum virulence factors NcGRA7 and NcROP40 in bovine target cells
    (Elsevier, 2023-06-14) Rico San Román, Laura; Amieva, Rafael; Horcajo Iglesias, María Del Pilar; García Sánchez, Marta Eulalia; Pastor Fernández, Iván; Ortega Mora, Luis Miguel; Collantes Fernández, Esther
    Bovine neosporosis is one of the major causes of reproductive failure in cattle worldwide, and differences in virulence between isolates have been widely shown. However, the molecular basis and mechanisms underlying virulence in Neospora caninum are mostly unknown. Recently, we demonstrated the involvement of NcGRA7 and NcROP40 in the virulence of N. caninum in a pregnant murine model using single knockout mutants in these genes generated by CRISR/Cas9 technology. In this study, the role of these proteins was investigated in two in vitro models using bovine target cells: trophoblast (F3 cell line) and monocyte-derived macrophages (BoMØ). The proliferation capacity of the single knockout mutant parasites was compared to the wild-type strain, the Nc-Spain7 isolate, using both cell populations. For the bovine trophoblast, no differences were observed in the growth of the defective parasites compared to the wild-type strain, neither in the proliferation kinetics nor in the competition assay. However, in naïve BoMØ, a significant decrease in the proliferation capacity of the mutant parasites was observed from 48 h pi onwards. Stimulation of BoMØ with IFN-γ showed a similar inhibition of tachyzoite growth in defective and wild-type strains in a dose-dependent manner. Finally, BoMØ infected with knockout parasites showed higher expression levels of TLR3, which is involved in pathogen recognition. These results suggest that NcGRA7 and NcROP40 may be involved in the manipulation of innate immune defense mechanisms against neosporosis and confirm the usefulness of the BoMØ model for the evaluation of N. caninum virulence mechanisms. However, the specific functions of these proteins remain unknown, opening the way for future research.
  • Publication
    Analysis of the culturable gut yeast microbiota of dogs with digestive disorders
    (Elsevier, 2024-01-09) Álvarez Pérez, Sergio; Rodríguez Franco, Fernando; Sainz Rodríguez, Ángel; García Sánchez, Marta Eulalia; García-Sancho Téllez, Mercedes Guadalupe; Tercero-Guerrero, Daniela; Blanco Cancelo, José Luis
    Despite the increasing interest in studying the gut mycobiota of dogs, the association between fungal colonization and the development of digestive disorders in this species remains largely understudied. On the other hand, the high prevalence of antifungal-resistant yeasts detected in previous studies in samples from animals represents a major threat to public health. We analyzed the presence of culturable yeasts in 112 rectal swab samples obtained from dogs with digestive disorders attended in a veterinary teaching hospital. Our results revealed that Malassezia pachydermatis was frequently isolated from the studied dog population (33.9% of samples), and that the isolation of this yeast was significantly associated to the age of animals, but not to their sex, disease group, or the presence of vomits and/or diarrhea. In contrast, other yeast species were less prevalent (17.9% of samples in total), and their isolation was not significantly associated to any variable included in the analysis. Additionally, we observed that 97.5% of the studied M. pachydermatis isolates (n = 158, 1–6 per positive episode) displayed a minimum inhibitory concentration (MIC) value >4 μg/ml to nystatin, 31.6% had a MIC ≥32 μg/ml to fluconazole, and 27.2% had a MIC >4 μg/ml to amphotericin B. The antifungal susceptibility profiles of non-Malassezia (n = 43, 1–7 per episode) were more variable and included elevated MIC values for some antifungal-species combinations. These results confirm that the intestine of dogs is a reservoir of opportunistic pathogenic yeasts and suggest that the prevalence of M. pachydermatis colonization depends more on the age of animals than on any specific digestive disorder.
  • Publication
    Presence of Aspergillus fumigatus with the TR34/L98H Cyp51A mutation and other azole-resistant aspergilli in the air of a zoological park
    (Elsevier, 2023-11) Álvarez Pérez, Sergio; García Sánchez, Marta Eulalia; Martínez Nevado, Eva; Blanco Cancelo, José Luis
    Antifungal-resistant fungi, including Aspergillus fumigatus and other Aspergillus species, pose an urgent threat to human and animal health. Furthermore, the environmental route of azole resistance selection due to the widespread use of azole fungicides in crop protection and other applications is a major public health issue. Although environmental surveillance of fungi is frequently performed in many zoological parks and wildlife rehabilitation centers, the antifungal susceptibility of recovered isolates is only rarely analyzed, which precludes a clear assessment of the threat posed by these fungi to captive animals. In this study, we assessed the presence of airborne azole-resistant Aspergillus spp., including the so-called ‘cryptic species’ (i.e., species which are phenotypically similar to more well-known aspergilli but clearly constitute different phylogenetic lineages) in a zoological park located in the city of Madrid, Spain. In general, our results revealed a low prevalence A. fumigatus and cryptic aspergilli with decreased susceptibility to azoles. However, we detected an A. fumigatus isolate with the TR34/L98H mutation in the gene encoding the lanosterol 14α-demethylase (Cyp51A), consisting of a tandem repeat of 34 base pairs in the promoter region and a lysine to histidine substitution at codon 98. Notably, this TR34/L98H mutation has been linked to the environmental route of azole resistance selection, thus highlighting the ‘One Health’ dimension of the emerging problem of antifungal resistance. In this context, continuous environmental surveillance of azole-resistant aspergilli in zoological parks and other similar animal facilities is recommended.
  • Publication
    Utilización de medios audiovisuales para la impartición de prácticas de Micología
    (2015-06-25) García Sánchez, Marta Eulalia; Blanco Cancelo, José Luis; García Cabrera, José Antonio; Álvarez Pérez, Sergio
  • Publication
    Laboratorio virtual de microbiología veterinaria
    (Editorial Complutense, 2007) Gómez-Lucía Duato, María Esperanza; Gibello Prieto, Alicia; Cutuli Simón, María Teresa; Aranaz Martín, Alicia; Blanco Gutiérrez, María Del Mar; Blanco Cancelo, José Luis; García Sánchez, Marta Eulalia; González Zorn, Bruno; Fernández-Garayzábal Fernández, José Francisco; Fernández-Valmayor Crespo, Alfredo; Fernández-Pampillón Cesteros, Ana María; Merino Granizo, Jorge
    Para el Proyecto de Innovación Educativa se ha realizado un CD como complemento a las prácticas de la Licenciatura de Veterinaria que tienen un componente microbiológico. Incluye aspectos fundamentales del ejercicio profesional (Toma de Muestras, Bioseguridad, Laboratorio de Virología), pero que con las infraestructuras actuales es casi imposible presentarlos al alumno de forma eficaz y personalizada. Para su desarrollo hemos elaborado el material escrito, apoyándolo con imágenes y videos explicativos. La confección del CD en sí ha sido realizada por una empresa de informática, siguiendo nuestras especificaciones y requerimientos.
  • Publication
    Elaboración de una galería fotográfica de microorganismos aislados de procesos patológicos animales
    (2019-06-27) García Sánchez, Marta Eulalia; Martín Espada, María Del Carmen; Santos Ocaña, Sandra; Neila Mota, Carlos; Blanco Cancelo, José Luis
    Se ha elaborado una galería de fotografías a partir de 77 casos clínicos diferentes. Dentro de cada uno de ellos se dispone tanto de fotos macroscópicas como microscópicas, hasta un total de 383 fotografías.