Characterization of liposomes coated with S-layer proteins from lactobacilli

The stability of liposomes coated with S-layer proteins from Lactobacillus brevis and Lactobacillus kefir was analyzed as a previous stage to the development of a vaccine vehicle for oral administration. The interactions of the different S-layer proteins with positively charged liposomes prepared with soybean lecithin or dipalmitoylphosphatidylcholine were studied by means of the variation of the Z potential at different protein-lipid ratios, showing that both proteins were able to attach in a greater extent to the surface of soybean lecithin liposomes. The capacity of these particles to retain carboxyfluorescein or calcein by exposure to bile salts, pancreatic extract, pH change and after a thermal shock showed that both S-layer proteins increased the stability of the liposomes in the same magnitude. The non-glycosylated protein from L. brevis protects more efficiently the liposomes at pH 7 than those from L. kefir even without treatment with glutaraldehyde.Centro de Investigación y Desarrollo en Criotecnología de Alimento

Characterization of liposomes coated with S-layer proteins from lactobacilli

The stability of liposomes coated with S-layer proteins from Lactobacillus brevis and Lactobacillus kefir was analyzed as a previous stage to the development of a vaccine vehicle for oral administration. The interactions of the different S-layer proteins with positively charged liposomes prepared with soybean lecithin or dipalmitoylphosphatidylcholine were studied by means of the variation of the Z potential at different protein-lipid ratios, showing that both proteins were able to attach in a greater extent to the surface of soybean lecithin liposomes. The capacity of these particles to retain carboxyfluorescein or calcein by exposure to bile salts, pancreatic extract, pH change and after a thermal shock showed that both S-layer proteins increased the stability of the liposomes in the same magnitude. The non-glycosylated protein from L. brevis protects more efficiently the liposomes at pH 7 than those from L. kefir even without treatment with glutaraldehyde.Centro de Investigación y Desarrollo en Criotecnología de Alimento

Detection of group a human rotavirus G9 genotype circulating in Córdoba, Argentina, as early as 1980

The incidence of human rotavirus G types wasdetermined over a 25-year period (1979–2003) byusing reverse transcription-PCR (RT-PCR) toexamine 519 stool specimens found to bepositive for rotavirus by enzyme linked immunosorbentassay (ELISA) or polyacrylamide gelelectrophoresis (PAGE). These stool sampleswere obtained from children under 3 years oldwho had been treated for acute diarrhea at publichospitals in Co´ rdoba, Argentina. The presentstudy describes the continued circulation of thecommon human G types G1 (53.8%), G2 (10.2%),G3 (4.4%), and G4 (27%), and also the detection ofthe unusual types G8 (0.5%) and G9 (4.2%).Genotype G9 was detected during the 1980–1988 and 1997–2003 periods at relatively lowrates. Rotavirus G types distribution was independentof age (1–18 months), gender or outpatientor in-patient status. Unexpectedly, 44.6%of mixed infections were detected, involvingcommon and unusual genotypes. Overall,95.4% of the typed strains belonged to the mostprevalent human serotypes (G1–G4) but thedetection of G9 infection throughout this studyperiod highlights the importance of this serotypeas a human pathogen.Fil: Barril, Patricia Angelica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología Dr. J. M. Vanella; ArgentinaFil: Martinez, L. C.. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología Dr. J. M. Vanella; ArgentinaFil: Giordano, M. O.. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología Dr. J. M. Vanella; ArgentinaFil: Castello, Alejandro Andrés. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Virología; ArgentinaFil: Rota, Rosana Paola. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Isa, Maria Beatriz. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología Dr. J. M. Vanella; ArgentinaFil: Masachessi, Gisela. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología Dr. J. M. Vanella; ArgentinaFil: Ferreyra, Leonardo Jesús. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología Dr. J. M. Vanella; ArgentinaFil: Glikmann, G.. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Virología; ArgentinaFil: Nates, Silvia Viviana. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología Dr. J. M. Vanella; Argentin

Reduced amygdala volumes are related to motor and cognitive signs in Huntington's disease: The IMAGE-HD study

In Huntington's disease (HD), the presence of neurodegeneration in brain regions other than the striatum has been recently gaining attention. The amygdala is one such area, which has been investigated in only eight structural magnetic resonance imaging studies to date, but with inconsistent findings. This is the largest MRI study to date examining manually traced amygdala volumes in HD participants and the relationship of amygdala volumes to clinical measures of HD. Our study included 35 healthy control participants, and groups of 35 pre-symptomatic, and 36 symptomatic HD participants. When comparing the pre-symptomatic and symptomatic HD groups together against the control group, amygdala volumes were significantly lower in HD than controls and in symptomatic HD than pre-symptomatic HD. When examining relationships between amygdala volumes and clinical measures of HD, significantly smaller amygdala volumes were associated with worse motor and cognitive signs. For pre-symptomatic HD participants who were close to disease onset, smaller amygdala volumes were also associated with higher levels of anxiety symptoms. These findings suggest that the amygdala is affected in pre-symptomatic and symptomatic HD, and that the amygdala is related to the clinical profile of HD before onset of motor symptoms. Keywords: Amygdala, Huntington's disease, Volumetry MRI, IMAGE-H

Pre-vaccine rotavirus surveillance in Buenos Aires, Argentina: Characterization of an emergent G1P[8] strain associated to fatal cases in 2014

Group A rotaviruses (RVA) are the most frequent etiological agents causing severe diarrhea in infants and surveillance of genotype, and genetic characteristics of circulating strains are necessary in order to evaluate vaccine programs. The objectives of this work were to describe G and P genotype from 2012 through 2014 in Buenos Aires, Argentina completing an overview of 19 years of genotype surveillance in our region and to characterize an emerging G1P[8] strain associated with severe cases and five fatalities in 2014. We performed genotyping by RT-PCR. The sequencing of several genes, phylogenetic analyses, and comparative epidemiological data were used to know the origin and phylogenetic relationships of the emerging G1P[8] strain. Along with this report, 19 years of continuous RVA genotype surveillance in Argentina in the pre-vaccine era was covered. During the last year of this surveillance, 2014, a significantly increased incidence of RVA associated gastroenteritis was related to the reemergence of G1P[8] strains, being these ones detected in low frequency in the last nine years. Interestingly, the patients affected were significantly older when compared with those from the last six seasons. Additionally, phylogenetic analysis of several genes infer that these G1P[8] strains were closely related to Asian strains circulating during 2012 and 2013. In addition to this, the suggested extra continental origin for the 2014 G1P[8] strains and the very low circulation of G1 type during nine years probably explain the increased incidence and severity in the gastroenteritis cases and the particular epidemiologic characteristics. In conclusion, this work gives us a whole panorama of the pre-vaccine era of the RVA molecular epidemiology in the most populated region of Argentina. In this way, this work inspires us to continue with this type of studies in the post-vaccination era.Fil: Mandile, Marcelo Gastón. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Virologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Argüelles, Marcelo Horacio. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Virologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Temprana, Carlos Facundo. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Virologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Peri Ibañez, Estefania Soledad. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Virologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Silvestre, Dalila. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Virologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Musto, Alejandra Beatriz. Gobierno de la Provincia de Buenos Aires. Hospital Provincial Evita Pueblo.; ArgentinaFil: Rodríguez Pérez, Alberto. Hospital General de Agudos Dr. Alberto A. Eurnekian; ArgentinaFil: Mistchenko, Alicia Susana. Gobierno de la Ciudad Autónoma de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez". Departamento de Medicina; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; ArgentinaFil: Almallo de Glikmann, Graciela. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Virologia; ArgentinaFil: Castello, Alejandro Andrés. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Virologia; Argentina. Universidad Nacional Arturo Jauretche; Argentin

Evaluation of the immunogenicity of a recombinant HSV-1 vector expressing human group C rotavirus VP6 protein

Group C Rotavirus (RVC) has been associated globally with sporadic outbreaks of gastroenteritis in children and adults. RVC also infects animals, and interspecies transmission has been reported as well as its zoonotic potential. Considering its genetic diversity and the absence of effective vaccines, it is important and necessary to develop new generation vaccines against RVC for both humans and animals. The aim of the present study was to develop and characterize an HSV-1-based amplicon vector expressing a human RVC-VP6 protein and evaluate the humoral immune response induced after immunizing BALB/c mice. Local fecal samples positive for RVC were used for isolation and sequencing of the vp6 gene, which phylogenetically belongs to the I2 genotype. We show here that cells infected with the HSV[VP6C] amplicon vector efficiently express the VP6 protein, and induced specific anti-RVC antibodies in mice immunized with HSV[VP6C], in a prime-boost schedule. This work highlights that amplicon vectors are an attractive platform for the generation of safe genetic immunogens against RVC, without the addition of external adjuvants.Fil: Rota, Rosana Paola. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Palacios, Carlos Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología "Dr. César Milstein". Fundación Pablo Cassará. Instituto de Ciencia y Tecnología "Dr. César Milstein"; ArgentinaFil: Temprana, Carlos Facundo. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Argüelles, Marcelo Horacio. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mandile, Marcelo Gastón. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mattion, Nora Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología "Dr. César Milstein". Fundación Pablo Cassará. Instituto de Ciencia y Tecnología "Dr. César Milstein"; ArgentinaFil: Laimbacher, Andrea S.. Universitat Zurich; SuizaFil: Fraefel, Cornell. Universitat Zurich; SuizaFil: Castello, Alejandro Andrés. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Almallo de Glikmann, Graciela. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentin

Characterization of liposomes coated with S-layer proteins from lactobacilli

The stability of liposomes coated with S-layer proteins from Lactobacillus brevis and Lactobacillus kefir was analyzed as a previous stage to the development of a vaccine vehicle for oral administration. The interactions of the different S-layer proteins with positively charged liposomes prepared with soybean lecithin or dipalmitoylphosphatidylcholine were studied by means of the variation of the Z potential at different protein-lipid ratios, showing that both proteins were able to attach in a greater extent to the surface of soybean lecithin liposomes. The capacity of these particles to retain carboxyfluorescein or calcein by exposure to bile salts, pancreatic extract, pH change and after a thermal shock showed that both S-layer proteins increased the stability of the liposomes in the same magnitude. The non-glycosylated protein from L. brevis protects more efficiently the liposomes at pH 7 than those from L. kefir even without treatment with glutaraldehyde.Centro de Investigación y Desarrollo en Criotecnología de Alimento