Sistema de Gestión del Conocimiento ANLIS MALBRÁN
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Serological study of brucellosis in Argentine Creole sheep
No full textFil: Lopez, G. Agricultural Sciences Faculty, Lomas de Zamora National University; Argentina.Fil: Peña, S. Agricultural Sciences Faculty, Lomas de Zamora National University; Argentina.Fil: Escobar, Gabriela I. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Hasan, Déborah B. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Lucero, Nidia E. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Ovine cattle was introduced into America during the Spanish conquest with the second journey of Columbus to the Antilles and was disseminated throughout the region. In 1587, sheep were introduced into Argentina, later developing into the "Creole" breed. We selected 486 animals from different Argentine provinces with the aim of determining the serological status of brucellosis caused by Brucella melitensis and Brucella ovis. For the detection of antibodies against smooth Brucella spp., the Rose Bengal test (RBT) was performed as screening test while the serum agglutination test (SAT) and 2 mercapto-ethanol (2ME) were run as a confirmatory technique. Moreover, for the detection of antibodies against rough Brucella spp., we used the rapid slide agglutination test (RSAT) for screening and an indirect ELISA (IELISA) as confirmatory assay. This study showed that the total positive percentage of brucellosis due to B. ovis was 2.9%. Excluding the animals mixed with the Suffolk breed; seropositivity would be 0.6%. All animals tested negative for brucellosis caused by B. melitensis
Caracterización de cepas de Coccidioides spp. circulantes en la República Argentina
No full textFil: Motter, Andrea Nora. ANLIS Dr.C.G.Malbrán. Unidad Operativa Centro de Contención Biológica; Argentina.Fil: Suárez Álvarez, Roberto Osvaldo. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento Micología; Argentina.Fil: Canteros, Cristina Elena. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento Micología; Argentina.Coccidioides es un género de hongos dimorfos, agentes causales de la coccidioidomicosis (CDM). A pesar de su restricción a las regiones geográficas áridas y semiáridas del continente Americano, esta micosis desatendida tiene un impacto sustancial en la salud pública. En los últimos veinte años se ha observado un aumento en la incidencia de la enfermedad e inclusive se han descripto nuevas áreas endémicas.
El género Coccidioides está compuesto por dos especies solo identificables por métodos moleculares: C. immitis, restringido a California, EE.UU. y estados aledaños, y C. posadasii en todas las Américas.
En Argentina, las regiones precordilleranas norte y central poseen las características ecológicas compatibles con el hábitat de Coccidioides spp. y es de donde provienen la mayoría de los casos de CDM del país. Hasta el momento, los pocos estudios realizados en donde se identificaron los aislados sugieren que en Argentina la especie circulante es C. posadasii, sin embargo, en otras regiones de América alejadas de California se detectaron casos clínicos autóctonos de CDM donde se aisló C. immitis.
El objetivo de este trabajo fue reconocer las especies y feno-genotipos de Coccidioides spp. circulantes en la República Argentina.
Se analizaron 47 cepas pertenecientes a 43 pacientes provenientes de diferentes regiones geográficas de Argentina aisladas desde 1967 a 2017 y siete cepas de pacientes mexicanos caracterizadas en origen como C. immitis, todas ellas depositadas en la colección de cultivos del Departamento Micología (DMic) de la ANLIS. Se realizó la identificación microbiológica clásica (observación microscópica, producción de exoantígeno y conversión de micelio a esférulas) y molecular, utilizando la secuenciación parcial del gen Ag2/PRA y de las regiones ITS1 e ITS2. Las secuencias obtenidas de cada región se alinearon y analizaron utilizando el programa BioEdit y se compararon cada una de ellas con las depositadas en el GenBank utilizando la herramienta BLAST/n. Se construyeron los árboles para cada grupo de secuencias y también un árbol consenso con las tres regiones analizadas, utilizando el método de máxima verosimilitud y el modelo de sustitución nucleotídica más acorde para el análisis con el programa MEGA v6.0. Se incluyeron secuencias depositadas en GenBank para enriquecer el análisis
Genotypic Features of Clinical and Bovine Escherichia coli O157 Strains Isolated in Countries with Different Associated-Disease Incidences
No full textFil: Pianciola, Luis. Subsecretaría de Salud de Neuquén. Laboratorio Central; Argentina.Fil: Rivas, Marta. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio Fisiopatogenia; Argentina.There is great geographical variation in the frequency of Escherichia coli O157 infections that correlates with important differences in the bovine reservoir of each country. Our group carried out a broad molecular characterization of human and bovine E. coli O157 strains circulating in Argentina using different methodologies. Our data allows us to conclude that in Argentina, a high homogeneity is observed in both cattle and human strains, with almost exclusive circulation of strains belonging to the hypervirulent clade 8 described by Manning. The aim of this review was to compare the genetic background of E. coli O157 strains isolated in countries that have conducted similar studies, to try to correlate specific O157 genotypes with the incidence and severity of E. coli O157 associated diseases. The characteristics of the strains that cause disease in humans reflect the predominant genotypes in cattle in each of the countries analyzed. The main features clearly linked to high incidence or severity of E. coli O157 infections are lineage-specific polymorphism assay-6 lineage I/II, clade 8 strains and probably, clade 6 strains, the stx2a/stx2c genotype, the presence of q933 and q21 simultaneously, and putative virulence factor EC_3286. In countries with an absence of these features in O157 strains, the overall incidence of O157 disease is low. Argentina, where these characteristics are detected in most strains, shows the highest incidence of hemolytic uremic syndrome (HUS) worldwide
Vaccine-elicited receptor-binding site antibodies neutralize two New World hemorrhagic fever arenaviruses
Get PDFFil: Clark, Lars E. Department of Microbiology and Immunobiology, Harvard Medical School, Boston; Estados Unidos.Fil: Mahmutovic, Selma. Laboratory of Molecular Medicine, Boston Children's Hospital, Harvard Medical School, Boston; Estados Unidos.Fil: Raymond, Donald D. Laboratory of Molecular Medicine, Boston Children's Hospital, Harvard Medical School, Boston; Estados Unidos.Fil: Dilanyan, Taleen. Department of Microbiology and Immunobiology, Harvard Medical School, Boston; Estados Unidos.Fil: Koma, Takaaki. Department of Pathology, University of Texas Medical Branch at Galveston, Galveston; Estados Unidos.Fil: Manning, John T. Department of Pathology, University of Texas Medical Branch at Galveston, Galveston; Estados Unidos.Fil: Shankar, Sundaresh. Department of Microbiology and Immunobiology, Harvard Medical School, Boston; Estados Unidos.Fil: Levis, Silvana C. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Briggiler, Ana M. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Enria, Delia A. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Wucherpfennig, Kai W. Laboratory of Molecular Medicine, Boston Children's Hospital, Harvard Medical School, Boston; Estados Unidos.Fil: Paessler, Slobodan. Department of Pathology, University of Texas Medical Branch at Galveston, Galveston; Estados Unidos.Fil: Abraham, Jonathan. Department of Microbiology and Immunobiology, Harvard Medical School, Boston; Estados Unidos.While five arenaviruses cause human hemorrhagic fevers in the Western Hemisphere, only Junin virus (JUNV) has a vaccine. The GP1 subunit of their envelope glycoprotein binds transferrin receptor 1 (TfR1) using a surface that substantially varies in sequence among the viruses. As such, receptor-mimicking antibodies described to date are type-specific and lack the usual breadth associated with this mode of neutralization. Here we isolate, from the blood of a recipient of the live attenuated JUNV vaccine, two antibodies that cross-neutralize Machupo virus with varying efficiency. Structures of GP1-Fab complexes explain the basis for efficient cross-neutralization, which involves avoiding receptor mimicry and targeting a conserved epitope within the receptor-binding site (RBS). The viral RBS, despite its extensive sequence diversity, is therefore a target for cross-reactive antibodies with activity against New World arenaviruses of public health concern
One hundred years after the "Spanish" flu
No full textFil: Lüthy, Isabel Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental; Argentina.Fil: Ritacco, Viviana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Kantor, Isabel N. Medicina (Buenos Aires). Comité de Redacción; Argentina.La pandemia de gripe “española”, de la que se cumplen 100 años, es considerada la más devastadora de la historia. Se estima que afectó a un tercio de la población mundial, y más del 2.5% de los enfermos murieron. Esta pandemia se presentó en dos oleadas principales, en 1918 y 1919, y la morbimortalidad por edades tuvo una curva en W. En general, la muerte no ocurría como consecuencia directa de la gripe, sino por bronconeumonías bacterianas, para las que se carecía de tratamiento. Hubo, además, una mayor mortalidad en enfermos con tuberculosis preexistente con respecto al resto de los afectados de influenza. En Argentina la epidemia también se presentó en dos oleadas principales, con amplias variaciones en la mortalidad por regiones. El tratamiento disponible incluía dieta, antisepsia de garganta, valerianato de quinina, salicilato, codeína para la tos y aceite alcanforado. También se aplicaban primitivas vacunas y sueros anti-neumococos. Con la disponibilidad de la secuencia de ARN completa del genoma del virus de la influenza 1918 ha sido posible ensamblar, mediante genética inversa, partículas virales semejantes a las de la pandemia mortal. El virus reconstituido demostró ser extraordinariamente virulento para ratones. En la actualidad, la vacunación contra la gripe estacional reduce el riesgo de otra pandemia, pero por el momento no puede eliminarlo. El desarrollo de vacunas “universales” contra la gripe, que confieran inmunidad confiable y duradera, podrá evitar en el futuro su propagación mundial.
(EN) The "Spanish" flu pandemic, which occurred a century ago, is considered the most devastating in human history. An estimated one third of world population fell ill with flu and more than 2.5% of them died. The course of the epidemic had two main waves (1918 and 1919) and showed an unusual W-shaped morbidity/mortality distribution. Death was not a direct outcome of flu itself but rather a consequence of secondary bacterial bronchopneumonia, for which antibiotics had not yet been discovered. Pre-existing pulmonary tuberculosis was also accountable for increased flu death rates during the pandemic. As it happened in Europe, in Argentina the epidemic had two main waves, with ample variation in mortality by region. Available treatment at the time included diet, throat antiseptic rinses, low doses of quinine valerianate, salicylates, codeine as a cough suppressant, and camphor oil. Primitive anti-pneumococcal vaccines and immune sera were also applied. Upon the disclosure of the whole RNA sequence of the 1918 influenza virus genome, by means of reverse genetics it was possible to assemble viral particles resembling those of the deadly pandemic. The reconstituted virus proved to be extraordinarily virulent for mice. Current seasonal flu vaccines help to reduce, but not to abolish, the risk of another pandemic. The ongoing development of "universal" vaccines against influenza conferring reliable and long-lasting immunity may prevent its global spread in the future
Global expansion of Mycobacterium tuberculosis lineage 4 shaped by colonial migration and local adaptation
Get PDFFil: Brynildsrud, Ola B. Norwegian Institute of Public Health. Division of Infectious Diseases and Environmental Health; Noruega.Fil: Pepperell, Caitlin S. University of Wisconsin-Madison. School of Medicine and Public Health. Department of Medicine. Division of Infectious Disease; Estados Unidos.Fil: Suffys, Philip. Oswaldo Cruz Institute. Laboratory of Molecular Biology Applied to Mycobacteria; Brasil.Fil: Grandjean, Louis. Imperial College London. Department of Paediatric Infectious Diseases; Reino Unido.Fil: Monteserin, Johana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Debech, Nadia. Norwegian Institute of Public Health. Division of Infectious Diseases and Environmental Health; Noruega.Fil: Bohlin, Jon. Norwegian Institute of Public Health. Division of Infectious Diseases and Environmental Health; Noruega.Fil: Alfsnes, Kristian. Norwegian Institute of Public Health. Division of Infectious Diseases and Environmental Health; Noruega.Fil: Pettersson, John O-H. Norwegian Institute of Public Health. Division of Infectious Diseases and Environmental Health; Noruega.Fil: Kirkeleite, Ingerid. Norwegian Institute of Public Health. Division of Infectious Diseases and Environmental Health; Noruega.Fil: Fandinho, Fatima. Centro de Referência Professor Hélio Fraga. Laboratorio de Bacteriologia da Tuberculose; Brasil.Fil: Silva, Marcia Aparecida da. Centro de Referência Professor Hélio Fraga. Laboratorio de Bacteriologia da Tuberculose; Brasil.Fil: Perdigao, Joao. Universidade de Lisboa. Instituto de Investigação do Medicamento. Faculdade de Farmácia; Portugal.Fil: Portugal, Isabel. Universidade de Lisboa. Instituto de Investigação do Medicamento. Faculdade de Farmácia; Portugal.Fil: Viveiros, Miguel. Universidade Nova de Lisboa. Instituto de Higiene e Medicina Tropical. Unidade de Microbiologia Medica; Portugal.Fil: Clark, Taane. London School of Hygiene and Tropical Medicine. Faculty of Infectious and Tropical Diseases; Reino Unido.Fil: Caws, Maxine. Liverpool School of Tropical Medicine. Department of Clinical Sciences; Reino Unido.Fil: Dunstan, Sarah. University of Melbourne. Peter Doherty Institute for Infection and Immunity; Australia.Fil: Thai, Phan Vuong Khac. Pham Ngoc Thach Hospital for TB and Lung Diseases; Vietnam.Fil: López, Beatriz. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Ritacco, Viviana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Kitchen, Andrew. University of Iowa. Department of Anthropology; Estados Unidos.Fil: Brown, Tyler S. Massachusetts General Hospital. Division of Infectious Diseases; Estados Unidos.Fil: van Soolingen, Dick. National Institute for Public Health and the Environment. Center for Infectious Disease Research, Diagnostics and Perinatal Screening; Países Bajos.Fil: O'Neill, Mary B. University of Wisconsin-Madison. School of Medicine and Public Health. Department of Medical Microbiology and Immunology; Estados Unidos.Fil: Holt, Kathryn E. London School of Hygiene and Tropical Medicine. Faculty of Infectious and Tropical Diseases; Reino Unido.Fil: Feil, Edward J. University of Bath. Milner Centre for Evolution. Department of Biology and Biochemistry; Reino Unido.Fil: Mathema, Barun. Columbia University. Mailman School of Public Health; Estados Unidos.Fil: Balloux, Francois. University College London. University College London Genetics Institute; Reino Unido.Fil: Eldholm, Vegard. Norwegian Institute of Public Health. Division of Infectious Diseases and Environmental Health; Noruega.On the basis of population genomic and phylogeographic analyses of 1669 Mycobacterium tuberculosis lineage 4 (L4) genomes, we find that dispersal of L4 has been completely dominated by historical migrations out of Europe. We demonstrate an intimate temporal relationship between European colonial expansion into Africa and the Americas and the spread of L4 tuberculosis (TB). Markedly, in the age of antibiotics, mutations conferring antimicrobial resistance overwhelmingly emerged locally (at the level of nations), with minimal cross-border transmission of resistance. The latter finding was found to reflect the relatively recent emergence of these mutations, as a similar degree of local restriction was observed for susceptible variants emerging on comparable time scales. The restricted international transmission of drug-resistant TB suggests that containment efforts at the level of individual countries could be successful
Distinct Treatment Outcomes of Antiparasitic Therapy in Trypanosoma cruzi-Infected Children Is Associated With Early Changes in Cytokines, Chemokines, and T-Cell Phenotypes
Get PDFBackground: In contrast to adults, Trypanosoma cruzi-infected children have more broadly functional Trypanosoma cruzi-specific T cells, and the total T-cell compartment exhibits fewer signs of immune exhaustion. However, not much is known about the link between immunocompetence and the treatment efficacy for human Chagas disease. Methods: Using cytokine enzyme-linked immunosorbent spot (ELISPOT) polychromatic flow cytometry, cytometric bead assay, multiplex serological assays and quantitative PCR, we evaluated T. cruzi-specific T-cell and antibody immune responses, T-cell phenotypes and parasitemia in children in the early chronic phase of Chagas disease undergoing anti-Trypanosoma cruzi treatment. Results: Treatment with benznidazole or nifurtimox induced a decline in T. cruzi-specific IFN-γ- and IL-2-producing cells and proinflammatory cytokines and chemokines. T-cell responses became detectable after therapy in children bearing T-cell responses under background levels prior to treatment. The total frequencies of effector, activated and antigen-experienced T cells also decreased following anti-T. cruzi therapy, along with an increase in T cells expressing the receptor of the homeostatic cytokine IL-7. Posttreatment changes in several of these markers distinguished children with a declining serologic response suggestive of successful treatment from those with sustained serological responses in a 5-year follow-up study. A multivariate analysis demonstrated that lower frequency of CD4+CD45RA-CCR7-CD62L- T cells prior to drug therapy was an independent indicator of successful treatment. Conclusions: These findings further validate the usefulness of alternative metrics to monitor treatment outcomes. Distinct qualitative and quantitative characteristics of T cells prior to drug therapy may be linked to treatment efficacy
Trypanosoma cruzi: death phenotypes induced by ortho-naphthoquinone substrates of the aldo-keto reductase (TcAKR). Role of this enzyme in the mechanism of action of β-lapachone
No full textFil: Garavaglia, Patricia A ANLIS Dr.C.G.Malbrán. Instituto Nacional de Parasitología; Argentina.Fil: Rubio, María Fernanda. Laboratorio de Biología Molecular y Apoptosis,Instituto de Investigaciones Médicas Alfredo Lanari (IDIM-CONICET),Universidad de Buenos Aires,Ciudad de Buenos Aires (1427); Argentina.Fil: Laverrière, Marc. Instituto de Investigaciones Biotecnológicas (IIB-INTECH),Universidad Nacional de General San Martín-CONICET,San Martín (1650),Prov. Buenos Aires; Argentina.Fil: Tasso, Laura Mónica. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Parasitología; Argentina.Fil: Fichera, Laura E. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Parasitología; Argentina.Fil: Cannata, Joaquín J B. Instituto de Investigaciones Biotecnológicas (IIB-INTECH),Universidad Nacional de General San Martín-CONICET,San Martín (1650),Prov. Buenos Aires; Argentina.Fil: García, Gabriela Andrea. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Parasitología; Argentina.Several ortho-naphthoquinones (o-NQs) have trypanocidal activity against Trypanosoma cruzi, the aetiological agent of Chagas disease. Previously, we demonstrated that the aldo-keto reductase from this parasite (TcAKR) reduces o-NQs, such as β-lapachone (β-Lap) and 9,10-phenanthrenequinone (9,10-PQ), with concomitant reactive oxygen species (ROS) production. Recent characterization of TcAKR activity and expression in two T. cruzi strains, CL Brener and Nicaragua, showed that TcAKR expression is 2.2-fold higher in CL Brener than in Nicaragua. Here, we studied the trypanocidal effect and induction of several death phenotypes by β-Lap and 9,10-PQ in epimastigotes of these two strains. The CL Brener strain was more resistant to both o-NQs than Nicaragua, indicating that greater TcAKR activity is unlikely to be a major influence on o-NQ toxicity. Evaluation of changes in ROS production, mitochondrial membrane potential, phosphatidylserine exposure and monodansylcadaverine labelling evidenced that β-Lap and 9,10-PQ induce different death phenotypes depending on the combination of drug and T. cruzi strain analysed. To study whether TcAKR participates in o-NQ activation in intact parasites, β-Lap and 9,10-PQ trypanocidal effect was next evaluated in TcAKR-overexpressing parasites. Only β-Lap was more effective and induced greater ROS production in TcAKR-overexpressing epimastigotes than in controls, suggesting that TcAKR may participate in β-Lap activation
Eficacia de la amplificación de la polimerasa con recombinasa para diagnosticar la infección por Trypanosoma cruzi en perros con alteraciones cardíacas en un área endémica de México.
No full textChagas disease is a lingering Public Health problem in Latin America with ∼5.7 million people infected with Trypanosoma cruzi. Transmission is still taking place in most countries of the Americas, including the United States. Dogs are frequently infected with T. cruzi and its high infection prevalence is associated with increased risk of Chagas disease in humans. The city of Mérida in the Yucatan peninsula is endemic for Chagas disease and canines are frequently infected with T. cruzi. The objective of this study was to evaluate the performance of a qualitative point of care (POC) molecular test (RPA-LF, recombinase polymerase amplification-lateral flow) developed in our laboratory for identifying infected dogs. We used retrospective samples of dogs that came for consultation because of cardiac alterations and proved to be infected with T. cruzi as determined by enzyme-linked immunosorbent assay (ELISA), Western blot, and quantitative PCR (qPCR). The analytical sensitivity indicated that RPA-LF amplified T. cruzi DNA in samples containing almost equal to one to two parasites per reaction. Serial twofold dilutions of T. cruzi epimastigotes showed that the test had 95% (19/20) repeatability at concentrations of two parasites per reaction. The test showed no cross reactivity with human DNA or other protozoan parasites (Trypanosoma rangeli, Leishmania spp., and Plasmodium spp.). RPA-LF had the capacity to amplify all discrete typing units (DTUs I-VI) of T. cruzi that circulate in domestic or extradomestic environments. The RPA-LF had 93.2% (95% confidence interval 87.2-98.1) sensitivity and excellent agreement with qPCR used as gold standard (Cohen's Kappa test = 0.963). ELISA was positive in 96.6% (85/88) of dogs, which together with the molecular tests confirmed the frequent contact with infected triatomine bugs in the city of Mérida. These preliminary results on the diagnostic efficacy of the RPA-LF deserve further large-scale field testing of this POC test for T. cruzi infection in endemic areas
Prevalence of intestinal parasites and the absence of soil-transmitted helminths in Añatuya, Santiago del Estero, Argentina
No full textFil: Periago, Maria Victoria. Consejo Nacional de Investigaciones Científica y Técnicas (CONICET); Argentina.Fil: García, Rocio. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Astudillo, Osvaldo Germán. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Cabrera, Marta. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Abril, Marcelo Claudio. Fundación Mundo Sano, Paraguay, 1535, Buenos Aires; Argentina.Intestinal parasites (IP) have been reported in point studies from different provinces of Argentina. The presence of soil-transmitted helminths (STH) was detected in many of these studies, including varied prevalences of all five species of STH in the north were the climate is more appropriate for transmission. Nonetheless, Argentina lacks a comprehensive prevalence map of STH. Therefore, the objective of this study was to determine the prevalence of intestinal parasites, focusing on STH, in rural and peri-urban areas of Añatuya, Santiago del Estero Province and identifying risk factors for their transmission