La Maestría Internacional en Ciencias Biomédicas y su impacto en la internacionalización de la Facultad de Farmacia y Bioquímica de la Universidad de Buenos Aires

La Maestría Internacional en Ciencias Biomédicas IMBS es una Maestría conjunta entre las Facultades de Farmacia y Bioquímica, y la Facultad de Medicina de la Universidad de Buenos Aires (Argentina), con la Universidad Albert-Ludwigs de Friburgo (Alemania). La creación de este Programa binacional produjo un fuerte impacto en la internacionalización de nuestra Institución. Los resultados se visibilizan en el crecimiento de capacidades académicas, en cooperación científica, movilidad estudiantil y docente. La creación de una estructura administrativa con personas capacitadas fue crucial para el éxito de una gestión internacional.

Application of Molecular Typing Methods to the Study of Medically Relevant Gram-Positive Cocci

The development of molecular genotyping methods has been a landmark in the possibility of classifying microorganisms below the species level. The ability to differentiate efficiently related bacterial isolates is essential for the control of infectious diseases and has become a necessary technology for clinical microbiology laboratories. The aim of this chapter is to provide an overview of the methods available for analyzing bacterial isolates, focusing on those methods employed for typing Streptococcus pneumoniae and Staphylococcus aureus. Different molecular approaches have been used to better understand the epidemiology of these medically relevant gram-positive cocci.Fil: Bonofiglio, Laura. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Microbiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gardella, Noella Mariel. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Microbiología; ArgentinaFil: Mollerach, Marta Eugenia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Microbiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Community-associated methicillin-resistant Staphylococcus aureus skin and soft tissue infections in a pediatric hospital in Argentina

Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) emerged at the Pediatric Hospital of Misiones Province, north Argentina, in 2003 as a cause of community-acquired (CA) infections, mostly associated with skin and soft tissue infections (SSTIs). This study aimed to assess the microbiological, epidemiological, and clinical features of CA-MRSA SSTIs treated at the hospital. Methodology: From 2003 through 2006, a longitudinal study on CA-MRSA SSTIs was conducted. Clinical, bacteriological, and molecular data were collected and analyzed by multiple correspondences and cluster analysis (MCCA). Results: A total of 138 children were enrolled; 55.8% of the children required hospitalization. The main clinical presentation was abscesses (51%). Antibiotic therapy in the previous six months was registered in 41% of the patients, and 72% of the patients had relatives with similar symptoms. Resistance to non-b-lactam antibiotics was found in less than 12% of patients. All 44 isolates carried staphylococcal cassette chromosomemec (SCCmec) type IV, and 30/44 had Panton-Valentine leucocidin (PVL) coding genes. Six pulsed-field gel electrophoresis (PFGE) patterns were detected from 17 isolates. MCCA hierarchic classification resulted in four distinctive patient classes (new variable). No relationship could be observed regarding the PVL detection, as PVL (+) isolates were detected in all classes; the same lack of significance was observed concerning the distribution of resistance to non-β-lactam antibiotics. Conclusions: This study increases the understanding and knowledge about CA-MRSA skin and soft tissue infections in pediatric patients. Continuous efforts should be made to control this significant public health problem.Fil: Von Specht, Martha Helena. Provincia de Misiones. Ministerio de Salud de la Provincia de Misiones. Hospital Publico Provincial de Pediatria de Autogestion Dr. Fernando Barreyro; Argentina. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; ArgentinaFil: Gardella, Noella Mariel. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Ubeda, Clotilde. Dirección Nacional del Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr.C.G.Malbran". Instituto Nacional de Epidemiologia; ArgentinaFil: Grenon, Sandra Liliana. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina. Provincia de Misiones. Ministerio de Salud de la Provincia de Misiones. Hospital Publico Provincial de Pediatria de Autogestion Dr. Fernando Barreyro; ArgentinaFil: Gutkind, Gabriel Osvaldo. Dirección Nacional del Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr.C.G.Malbran". Instituto Nacional de Epidemiologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mollerach, Marta Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Dirección Nacional del Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr.C.G.Malbran". Instituto Nacional de Epidemiologia; Argentin

The International Master Program in Biomedical Sciences and the impact in the internationalization of the Faculty of Pharmacy and Biochemistry, Universidad de Buenos Aires

La Maestría Internacional en Ciencias Biomédicas IMBS es una Maestría conjunta entre las Facultades de Farmacia y Bioquímica, y la Facultad de Medicina de la Universidad de Buenos Aires (Argentina), con la Universidad Albert-Ludwigs de Friburgo (Alemania). La creación de este Programa binacional produjo un fuerte impacto en la internacionalización de nuestra Institución. Los resultados se visibilizan en el crecimiento de capacidades académicas, en cooperación científica, movilidad estudiantil y docente. La creación de una estructura administrativa con personas capacitadas fue crucial para el éxito de una gestión internacional.The International Master Program in Biomedical Sciences IMBS is a joint Program between the Faculty of Pharmacy and Biochemistry, the Faculty of Medicine (Universidad de Buenos Aires, Argentina) and Albert-Ludwigs University of Freiburg (Germany). In the following paper we will analyze the results produced by the incorporation of this master’s course to the academic curriculum of the Faculty of Pharmacy and Biochemistry in terms of the international insertion of this institution. We will study this process through the notion of internationalization of superior education, which allows us to address the issue from its multiple dimensions. The impact of the IMBS has become visible through the growth of academic skills, scientific cooperation, student and faculty mobility. Furthermore, we consider that the development of an administrative structure with highly qualified staff has been crucial to the success of the international management of our programFil: Mollerach, Marta Eugenia. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Arranz, Cristina Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; Argentin

Molecular characterization of InJR06, a class 1 integron located in a conjugative plasmid of Salmonella enterica ser. Typhimurium

The presence of class 1, 2, and 3 integrons was investigated in four pediatric isolates of Salmonella enterica ser. Typhimurium (S. Typhimurium). A class 1 integron was detected in one S. Typhimurium strain, the only one that also showed resistance to various aminoglycoside antibiotics. This integron, called InJR06, and the aminoglycoside resistance determinants were located in pS06, a large (≥55 kb) conjugative plasmid. Asingle mobile cassette (encoding the aminoglycoside adenylyltransferase ANT(3´´)-Ia) was detected in the variable region of InJR06, while the architecture of the attI1 and attC sites was conserved. [Int Microbiol 2005; 8(4):287-290

All Detectable High-Molecular-Mass Penicillin-Binding Proteins Are Modified in a High-Level β-Lactam-Resistant Clinical Isolate of Streptococcus mitis

All detectable high-molecular-mass penicillin-binding proteins (HMM PBPs) are altered in a clinical isolate of Streptococcus mitis for which the b-lactam MICs are increased from those previously reported in our region (cefotaxime MIC, 64 mg/ml). These proteins were hardly detected at concentrations that saturate all PBPs in clinical isolates and showed, after densitometric analysis, 50-fold-lower radiotracer binding. Resistance was related to mosaic structure in all HMM PBP-coding genes, where critical region replacement was complemented not only by substitutions already reported for the closely related Streptococcus pneumoniae but also by other specific replacements that are presumably close to the active-site serine. Mosaic structure was also presumed in a pbp1a-sensitive strain used for comparison, confirming that these structures do not unambiguously imply, by themselves, detectable critical changes in the kinetic properties of these proteins.Fil: Amoroso, Ana Maria. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Demares, Diego. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Mollerach, Marta Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Gutkind, Gabriel Osvaldo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Coyette, Jacques. Université de Liège; Bélgic

TNFR1 signaling contributes to T cell anergy during staphylococcus aureus sepsis

Early research on sepsis has focused on the initial hyper-inflammatory, cytokine mediated phase of the disorder whereas the events that govern the concomitant and subsequent anti-inflammatory compensatory response are not completely understood. In this context, the putative participation of TNFR1-mediated signaling in the immunosuppressive phase of Staphylococcus aureus sepsis has not been elucidated. The aim of this study was to determine the role of TNFR1 in directing the immune dysfunction during S. aureus sepsis and the potential contribution of MDSC to this process. Using a model of sepsis of peritoneal origin and tnfr1 -/- mice, we demonstrated that during staphylococcal sepsis CD4 + T cell anergy is significantly dependent on TNFR1 expression and that signaling through this receptor has an impact on bacterial clearance in the spleen. MDSC played a major role in the generation of anergic CD4 + T cells and their accumulation in the spleen during S. aureus sepsis correlated with IL-6 induction. Although TNFR1 signaling was not required for MDSC accumulation and expansion in the spleen, it determined the in vivo expression of Arginase 1 and iNOS, enzymes known to participate in the suppressive function of this population. Moreover, our data indicate that TNFR1-mediated IL-10 production may modulate MDSC function during staphylococcal sepsis. Taken together these results indicate that TNFR1 plays a critical role on T cell dysfunction during S. aureus sepsis by regulating immunomodulatory mediators in MDSC. The role of TNFR1-mediated signaling during the immunosuppressive phase of staphylococcal sepsis should be considered when designing novel alternative therapeutic approaches.Fil: Ledo, Camila. Universidad Maimónides; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Gonzalez, Cintia Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Poncini, Carolina Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Mollerach, Marta Eugenia. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gomez, Marisa Ines. Universidad Maimónides; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentin

Endocarditis caused by methicillin-susceptible Staphylococcus aureus with reduced susceptibility to vancomycin: a case report

Staphylococcus aureus is the most common cause of acute infective endocarditis. Recent reports have described heteroresistance to vancomycin associated with methicillin-resistant Staphylococcus aureus. We present the first case report in Argentina of the failure of treatment with vancomycin in endocarditis caused by methicillin-susceptible Staphylococcus aureus containing subpopulations with reduced susceptibility to vancomycin. Case presentation: We report the case of a 66-year-old Hispanic man with infective endocarditis complicated by septic emboli in the lumbosacral spine and the left iliopsoas muscle. This disease was caused by methicillin susceptible Staphylococcus aureus containing subpopulations with reduced susceptibility to vancomycin. He was initially treated with cephalothin and gentamicin but developed a rash caused by beta-lactams and interstitial nephritis. For that reason, the treatment was subsequently switched to vancomycin but he failed to respond. The infection resolved after administration of vancomycin in combination with gentamicin and rifampin. Conclusion: Our case report provides important evidence for the existence of subpopulations of methicillin susceptible Staphylococcus aureus that have reduced susceptibility to vancomycin which would account for treatment failure. Our case raises an alert about the existence of these strains and highlights the need to determine the vancomycin minimum inhibitory concentration of Staphylococcus aureus to screen for the presence of strains that have reduced vancomycin susceptibility at different infection sites.Fil: Perazzi, Beatriz. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Bello, Natalia. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Mollerach, Marta Eugenia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Vay, Carlos. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Lasala, María Beatriz. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Famiglietti, Angela. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentin

Community-associated methicillin-resistant Staphylococcus aureus in children treated in Uruguay

Introduction: Staphylococcus aureus produces a variety of diseases among children, ranging from skin and soft tissue infections to invasive life-threatening diseases. Since 1990, an increasing number of diseases produced by community-associated methicillin-resistant S. aureus (CA-MRSA) isolates have been reported. The aim of this study was to describe the importance and the microbiological characteristics of S. aureus isolates recovered from children treated at the Hospital Pediátrico del Centro Hospitalario ?Pereira Rossell? (HP-CHPR); focusing on invasive diseases caused by CA-MRSA isolates, as well as some clinical aspects of the diseases they have produced. Methodology: One hundred and twenty-five S. aureus isolates recovered from the HP-CHPR between 2003 and 2006 from children with invasive (n=89) and superficial diseases (n=36) were included. Genotypic and phenotypic characteristics of S. aureus isolates and relevant clinical aspects of each child were studied. Results: CA-MRSA isolates accounted for 73% of all S. aureus recovered from invasive (mainly bone and joint) infections, pneumonia and bacteraemia. The most common CA-MRSA strain recovered from invasive (n=65) and superficial (n=36) diseases had the following features: pulsotype A (type USA1100), SCCmec cassette type IV, Panton-Valentine Leukocidin genes positive, susceptibility to trimethoprim-sulfamethoxazole without the inducible macrolide-lincosamide-streptogramin B (iMLSB) resistance phenotype. No association between genotypic characteristics of invasive CA-MRSA isolates and clinical outcomes was found. Conclusions: CA-MRSA isolates produced a wide spectrum of invasive diseases in a public paediatric hospital between 2003 and 2006. Microbiologic characterization suggests the spread of an adapted CA-MRSA clone lacking erm genesFil: Pardo, Lorena. Universidad de la Republica; UruguayFil: Vola, Magdalena. Universidad de la Republica; UruguayFil: Macedo Viñas, Marina. Universidad de la Republica; UruguayFil: Machado, Virginia. Universidad de la Republica; UruguayFil: Cuello, Dianna. Universidad de la Republica; UruguayFil: Mollerach, Marta Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Castro, Marta. Universidad de la Republica; UruguayFil: Pirez, Catalina. Universidad de la Republica; UruguayFil: Varela, Gustavo. Universidad de la Republica; UruguayFil: Algorta, Gabriela. Universidad de la Republica; Urugua