Showing papers in "Revista Argentina De Microbiologia in 2013"
TL;DR: The methanolic and ethanolic extracts of yerba mate were evaluated against food pathogens through minimum inhibitory and bactericidal concentrations and the most effective extract had its activity evaluated under different pH conditions by growth curve analysis.
Abstract: Yerba mate (Ilex paraguariensis St. Hil.) has been studied for its important biological activities mainly attributed to phenolic compounds. This study evaluated the antimicrobial activity of methanolic and ethanolic extracts of yerba mate against food pathogens, such as Staphylococcus aureus, Listeria monocytogenes, Salmonella Enteritidis and Escherichia coli through minimum inhibitory (MIC) and bactericidal (MBC) concentrations, in addition to the determination of chemical composition by gas chromatography with mass spectrometry (GC-MS) and phenolic content. The most effective extract had its activity evaluated under different pH conditions by growth curve analysis. All microorganisms except E. coli were inhibited. The ethanolic extract showed the lowest MIC/MBC (0.78/0.78 mg/ml), the highest phenolic content (193.9 g.GAE/kg) and the presence of chlorogenic acid derivatives, especially 3-O-caffeoylquinic and caffeic acid. This extract was able to inhibit microbial growth at pH 7 and 8.
44 citations
TL;DR: Juarez et al. as discussed by the authors present a study of the impact of the use of artificial intelligence on the development of the industrial quimica in the context of the CONICET project.
Abstract: Fil: Juarez, Maria Mercedes. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico - CONICET - Salta. Instituto de Invest.para la Industria Quimica (i); Argentina;
25 citations
TL;DR: The response of indigenous cyanobacteria to As(III) and As(V), including the species Tolypothrix tenuis, Nostoc muscorum and Nostoc minutum, previously used with biotechnological purposes are presented.
Abstract: The arsenic content of various water bodies in Argentina is higher than the acceptable levels for human and animal uses. Cyanobacteria are widely distributed in aquatic environments and can bioaccumulate arsenic (As). This study presents the response of indigenous cyanobacteria to As(III) and As(V), including the species Tolypothrix tenuis, Nostoc muscorum and Nostoc minutum, previously used with biotechnological purposes. As(III) resulted more toxic than As(V) in all cases, causing cell death in the range of 5-20 mg/l. T. tenuis growth was sensitive to As(V) with lethal inhibition at 625 mg/l, whereas the Noctoc species were stimulated. EC50 values found were 73.34 mg/l for N. muscorum and 989.3 mg/l for N. minutum. Batch cultures of N. minutum showed improvements in both growth parameters and photosynthetic pigment content in the presence of 1,000 mg/l As(V). Increases of 66.7%, 75.5%, 40% and 20.7% in cell productivity, chlorophyll a, total carotenoids and C-phycocyanin respectively were observed, reaching a bioaccumulated arsenic value of 37.4 μg/g at the stationary growth phase. © 2012 Asociacion Argentina de Microbiologia. Published by Elsevier Espana, S.L. All rights reserved.
24 citations
TL;DR: In this article, the anticandidal activity of oak gall extract, Quercus infectoria (QIE), was investigated as a potential natural alternative to synthetic and chemical fungicides.
Abstract: Candida albicans, one of the most dreadful fungal pathogens threatening humans, could not be easily prevented. The anticandidal activity of oak gall extract, Quercus infectoria (QIE), was investigated as a potential natural alternative to synthetic and chemical fungicides. QIE anticandidal potentiality was confirmed using both qualitative and quantitative assays. Cotton textiles were treated with QIE and then evaluated as anticandidal fabrics. QIE-treated textiles had a potent anticandidal activity, which could completely inhibit the inoculated C. albicans cells. The durability of anticandidal activity in QIE-treated textiles almost completely disappeared after the fourth laundering cycle. QIE could be recommended, however, as a potent anticandidal agent for preparing antiseptic solutions and emulsions and as a finishing agent for manufacturing anticandidal disposable diapers and hygienic clothes.
18 citations
Journal Article•
TL;DR: In vivo and in vitro studies of the substrate specificity of RBest1, using triacylglycerols or nitrophenyl-esters, revealed that the enzyme is highly specific for butyrate (C4) compounds, behaving as an esterase rather than a lipase.
Abstract: Resumen en: In order to isolate novel organic solvent-tolerant (OST) lipases, a metagenomic library was built using DNA derived from a temperate forest soil sample. ...
16 citations
TL;DR: El objetivo de this estudio fue realizar the caracterizacion genetica de los aislamientos pertenecientes al complejo C. neoformans / C. gattii de origen clinico en el nordeste argentino.
Abstract: Cryptococcosis is a fungal infection caused by yeast species of Cryptococcus genus, particularly Cryptococcus neoformans/Cryptococcus gattii species complex. The knowledge of the cryptococcosis casuistic in northeastern Argentina is scarce and there is no information about the molecular types circulating in this area. The aim of this study was to genotyping C. neoformans/C. gattii complex clinical isolates obtained at Hospital “Dr. Julio C. Perrando”, Resistencia city (Chaco, Argentina), in order to determine species, variety and molecular type. During two years and one month 26 clinical isolates were studied. Using conventional and molecular methods one isolate was identified as C. gattii VGI type, and 25 isolates as C. neoformans var. grubii; 23 of these belonged to VNI type and two belonged to VNII type. This data is a contribution to the knowledge of cryptococcosis epidemiology in Argentina and the first report about C. neoformans/C. gattii complex molecular types from clinical isolates in northeastern Argentina.
16 citations
TL;DR: The objectives of this study were to describe the prevalence of ermB and mefA genes in macrolide-resistant S. pneumoniae isolates from acute otitis media (AOM) and to determine their genetic relatedness.
Abstract: Macrolide-resistant Streptococcus pneumoniae emerged in Argentina in 1995, representing 26% of invasive infection isolates in children under 5 years old. The objectives of this study were to describe the prevalence of ermB and mefA genes in macrolide-resistant S. pneumoniae isolates from acute otitis media (AOM) and to determine their genetic relatedness. Between May 2009 and August 2010, 126 S. pneumoniae isolates from 324 otherwise healthy children with a fi rst episode of AOM were included. Twenty six of these isolates (20.6%) were resistant to erythromycin. Most frequent serotypes were: 14 (46.2%), 6A (23.1%), 19F (7.7%) and 9V (7.7%). Twenty (76.9%) carried the mefA gene, 5 (19.2%) have the ermB gene, and 1 (3.9%) both ermB + mefA. Ten clonal types were identifi ed, mostly related to Sweden
16 citations
TL;DR: The objective of this study was to determine the enzymatic profile of Vibrio parahaemolyticus strains isolated from Crassostrea rhizophorae oysters and to be aware of the bacteriological risk posed to human health by the consumption of raw or undercooked oysters.
Abstract: The enzymatic characterization of vibrios has been used as a virulence indicator of sanitary interest. The objective of this study was to determine the enzymatic profi le of Vibrio parahaemolyticus strains (n = 70) isolated from Crassostrea rhizophorae oysters. The strains were examined for the presence of gelatinase (GEL), caseinase (CAS), elastase (ELAS), phospholipase (PHOS), lipase (LIP), amilase (AML) and DNase. All enzymes, except elastase, were detected in more than 60% of the strains. The most recurrent enzymatic profi les were AML + DNase + PHOS + GEL + LIP (n = 16; 22.9%) and AML + CAS + DNase + PHOS + GEL + LIP (n = 21; 30%). Considering the fact that exoenzyme production by vibrios is closely related to virulence, one must be aware of the bacteriological risk posed to human health by the consumption of raw or undercooked oysters. © 2013 Asociacion Argentina de Microbiologia. Publicado por Elsevier Espana, S.L. Todos los derechos reservados.
15 citations
TL;DR: Staphylococcus aureus is the most prevalent mastitis pathogen in Argentina and worldwide and lack of effectiveness of traditional control measures based on milking hygiene and antibiotic therapy against this organism has led to the development of alternatives.
Abstract: Staphylococcus aureus is the most prevalent mastitis pathogen in Argentina and worldwide. Lack of effectiveness of traditional control measures based on milking hygiene and antibiotic therapy against this organism has led to the development of alternatives
15 citations
Journal Article•
TL;DR: The present work sought to detect the presence of Pseudomonas spp.
Abstract: Resumen en: The present work sought to detect the presence of Pseudomonas spp. at different stages of an effluent treatment plant using the Australian system of stab...
14 citations
Journal Article•
TL;DR: Se describe el primer caso documentado de endocarditis por Brucella canis en Argentina y el paciente fue un varon adulto que consulto por edemas en miembr...
Abstract: We herein present the case of an adult male patient who consulted for lower extremity edema, a 2- month history of fever and oppressive chest pain radiating to the left arm. He referred neither contact with breeding animals nor consumption of unpasteurized dairy products. A diagnosis of endocarditis was confirmed by cardiac studies. Since the empirical treatment with cephalotin, ampicillin and gentamicin failed, the patient underwent aortic valve replacement. A total of four blood cultures were positive with a gram-negative rod. Bacterial identification was performed using the API 20 NE technique (bioMerieux), the Phoenix automated method (BD) and conventional biochemical tests which were unable to classify the isolate as to genus and species. The strain was sent to the INEI-ANLIS "Dr. Carlos G. Malbran" where it was identified as Brucella canis. The antimicrobial treatment was switched to doxycycline, rifampicin and trimethoprim-sulfamethoxazole with good evolution of the patient. The clinical significance of this case report lies in the possible failure of the empiric antibiotic therapy administered for endocarditis, since B. canis did not respond to the conventional antimicrobial treatment for this pathology.
Journal Article•
TL;DR: Differences in the prevention of INV were crucial for the decision to include the 13-valent vaccine in the national calendar for children less than two years old in Argentina.
Abstract: Resumen en: A 16-month prospective, descriptive study was conducted on pneumococcal serotype distribution isolated from children with acute otitis media (AOM ) and i...
TL;DR: Pulsed-field gel electrophoresis analysis showed a genetic relationship between the C. malonaticus isolates from two patients and the foodborne isolates previously identified in the country, and characterized and subtype clinical isolates of Cronobacter spp.
Abstract: Cronobacter species are opportunistic pathogens associated with severe infections in neonates and immunocompromised infants. From January 2009 through September 2010, two cases of neonatal infections associated with Cronobacter malonaticus and one case associated with Cronobacter sakazakii, two of them fatal, were reported in the same hospital. These are the first clinical isolates of Cronobacter spp. in Argentina. The objective of this work was to characterize and subtype clinical isolates of Cronobacter spp. in neonate patients, as well as to establish the genetic relationship between these isolates and the foodborne isolates previously identified in the country. Pulsed-field gel electrophoresis analysis showed a genetic relationship between the C. malonaticus isolates from two patients. Different results were found when the pulsed-field gel electrophoresis patterns of clinical isolates were compared with those deposited in the National Database of Cronobacter spp.
Journal Article•
TL;DR: Leptospira reactivity in stray and household dogs in Campeche as well as associated risk factors to the seropositivity in household dogs have been identified and risk factors associated with this reactivity have been studied.
Abstract: Leptospira reactivity in stray and household dogs in Campeche as well as associated risk factors to the seropositivity in household dogs have been herein det...
TL;DR: Results suggest that i.p. passage enhances the expression of adherence in A. butzleri strains after serial intraperitoneal passage in mice.
Abstract: We investigated the possibility of enhancing the adherence capacity of four low-adherent Arcobacter butzleri strains after serial intraperitoneal passage (i.p.) in mice. All the strains enhanced their adherence capacity after the fi rst passage, increasing their adhesion rates after each passage. These results suggest that i.p. passage enhances the expression of adherence in A. butzleri strains. © 2013 Asociacion Argentina de Microbiologia. Published by Elsevier Espana, S.L. All rights reserved.
Journal Article•
TL;DR: The results confirm previous findings that amino acid substitutions in EmbB306, EmbB406 and EmbB497 are found only in MDR-TB strains but in both phenotypically resistant and sensitive strains, and suggest other undefined mutations can also confer ethambutol resistance.
Abstract: Resumen en: The relation of ethambutol resistance to embB mutations remains unclear, and there are no reports on ethambutol resistance from the Caribbean. We examine...
TL;DR: Se presenta el primer hallazgo de Echinococcus vogeli en una paca (Cuniculus paca) del bosque tropical de Misiones, norte argentino, y confirmo tambien la presencia oficial de su unico hospedador natural definitivo conocido, el perro silvestre.
Abstract: We report the first finding of Echinococcus vogeli in a paca, Cuniculus paca, in the tropical forest of Misiones, in the north of Argentina. The presence of the bush dog, Speothos venaticus, E. vogeli's only natural definitive host, was also reported. The polycystic hydatids, 2 to 3 cm in diameter, were only found in the liver of an adult paca. The size range of the hooks and the relative proportion blade/handle did not show significant differences with respect to the ones reported for E. vogeli. The size of E. granulosus hooks, measured for comparison purposes, was significantly smaller (p < 0.0001). These results confirmed the presence of E. vogeli in Argentina. The probability of finding neotropical echinococcosis in humans reinforces the need to expand the search for E. vogeli in Argentina. Echinococcosis due to E. vogeli is very aggressive and may cause death in about a third of the human population affected.
TL;DR: La introduccion de la vacuna contra Haemophilus influenzae tipo b en los programas de inmunizacion de muchos paises produjo una reduccion marcada en la incidencia de en-fermedad invasiva causada por this serotipo y en su portacion y un incremento de otros tipos capsulares y de aislamientos no capsulados.
Abstract: The introduction of the Haemophilus influenzae type b vaccine in the immunization programs of many countries has greatly reduced this invasive disease and the carriage caused by this serotype, also increasing other capsular types and non-capsular isolations. There were 313 isolations of H. influenzae under study, which were recovered from a sterile site coming from pediatric and adult patients carrying the invasive disease. Patients were treated at 90 different hospitals belonging to the Red Nacional de Laboratorios para Meningitis e Infecciones Respiratorias Agudas Bacterianas (National Lab Network for Meningitis and Acute Bacterial Respiratory Infections) from 2005 to 2010 for the following disorders: pneumonia, 40.3% (n=126), meningitis, 30.0% (n=94) and bacteremia, 26.5% (n=83). In pediatric patients (n=279), the highest frequency of isolations corresponded to children under the age of 2 years, 74.5% (n=208). Regarding type distribution, 61.3% corresponded to non-capsular H. influenzae (n=192), 20.1% to type b (n=63), 11.2% to type a (n=35), 4.8% to type f, and 2.6% to other types. Capsular H. influenzae was predominant in meningitis whereas non-capsular H. influenzae in pneumonia and bacteremia. The biotype was determined in 306 isolations. The totality (100%) of type a (n=35) was biotype II whereas 66.7% of type b (n=63) was biotype I. Slide agglutination and PCR tests were used in 220 isolations. There was a match of 0.982 (IC: 0.92-1.00) between them. During the last year, there was a great increase in type b, showing the importance of clinical and laboratory-based surveillance of the invasive disease caused by H. influenzae.
TL;DR: In this article, alternative algorithms were evaluated in order to reduce the number of false reactive results for antibodies against HTLV-1/2, and the ROC curve analysis determined that for an RP 4.74, the values for sensitivity, specificity, PPV and NPV by ELISA Murex were 100, 98.04, 95.8% and 100, respectively.
Abstract: Alternative algorithms were evaluated in order to reduce the number of false reactive results for antibodies against HTLV-1/2. From 20,210 samples tested, 0.37% (74/20,210) was reactive by ELISA Murex. Of these, 23 were confirmed as positive by the indirect immunofluorescence assay whereas 51 were negative, being the positive predictive value (PPV) 31.08%. From a combination of the ELISA Murex assay with the particle agglutination assay (PA) and ELISA MP, the following results were obtained: 26/74 were reactive by ELISA Murex and PA, PPV 88.5% and 32/74 were reactive by ELISA Murex and ELISA MP, PPV 71.8 %. The ROC curve analysis determined that for an RP 4.74, the values for sensitivity, specificity, PPV and NPV by ELISA Murex were 100%, 98.04%, 95.8% and 100%, respectively. We propose that reactive samples by ELISA Murex with an RP d 4.74 should be retested in duplicate by PA, and the resulting concordantly nonreactive samples should be defined as negative for HTLV-1/2.
TL;DR: El primer caso en Argentina de Staphylococcus aureus resistente a la meticilina adquirido en la comunidad con sensibilidad intermedia a la vancomicina y no sensibillidad a the daptomicina islámica islómica y mandatorio evaluar por CIM la sensibILidad a vancomicsina y a daptomaticina intratratamiento cu
Abstract: Resumen Describimos el primer caso en Argentina de Staphylococcus aureus resistente a la meticilina adquirido en la comunidad con sensibilidad intermedia a la vancomicina y no sensibilidad a la daptomicina. Caso clinico: Paciente masculino, con antecedente de insuficiencia renal cronica en hemodialisis y osteosintesis de cadera debido a una fractura. Se interno por sindrome febril persistente luego del desplazamiento de la protesis por un traumatismo. Se aislo de hemocultivos S. aureus resistente a la meticilina adquirido en la comunidad. Durante el tratamiento con vancomicina y daptomicina, se observo un aumento gradual de la CIM de vancomicina de 1 μg/ml (VSSA) a 2 μg/ml (h-VISA) y a 4 μg/ml (VISA), y la emergencia de no sensibilidad a daptomicina (CIM = 4 μg/ml). Al suspender la vancomicina y la daptomicina, la cepa revirtio al fenotipo de sensibilidad a ambas drogas. Es mandatorio evaluar por CIM la sensibilidad a vancomicina y a daptomicina intratratamiento cuando estas drogas se usan como terapia.
TL;DR: The aim of this work was the morphological and molecular identifi cation of this parasite and to achieve the molecular characterization of the parasite, ribosomal (28S) and mitochondrial (COI) DNA were used.
Abstract: In a rodent (Rattus norvegicus) survey in Buenos Aires province, metacestodes of tapeworms were found encysted in the liver of the host. The aim of this work was the morphological and molecular identification of this parasite. To achieve the molecular characterization of the parasite, ribosomal (28S) and mitochondrial (COI) DNA were amplified and sequenced. Based on both morphological and molecular data using bioinformatic tools, the metacestode was identified as Cysticercus fasciolaris. The adult form of this tapeworm (Taenia taeniaeformis) commonly infects felid and canid mammalian hosts. This is the first report on the molecular identification of Cysticercus fasciolaris in Buenos Aires province (Argentina).
TL;DR: In this article, the authors used immunodiagnostic techniques based on the identification of parasite antigens in dog dry faeces have been developed as alternatives for the surveillance of canine Echinococcosis.
Abstract: Cystic Echinococcosis is a major public health issue. Immunodiagnostic techniques based on the identification of parasite antigens in dog dry faeces have been developed as alternatives for the surveillance of canine Echinococcosis. The environmental conditions favouring the parasite cycle were met in the border of La Quiaca-Villazon, given the presence of definitive (dog) and intermediate hosts (sheep and goats). The most important activity in La Puna is sheep and goat rearing; slaughtering is carried out almost exclusively in the field by sheep's owners, and preventive health measures do not apply. The aim of this study was to determine the presence of dogs parasitized by Echinococcus granulosus in this border region. A hundred and sixty eight (168) stool specimens were collected during 2006. La Quiaca samples were taken from the following selected areas: the semi-rural area of Barrios, the rural areas of Santa Catalina, Yavi Chico, El Portillo, Pumahuasi and Cara Cara and the urban area of La Quiaca; selected urban areas in Villazon and the semi-rural area of Ojo de Agua, Lampaya and Matancillas. The samples were analyzed by copro-ELISA -Western blot test. The cities of San Francisco and Barrios had a prevalence of 14.3% and 6.7%, respectively. A prevalence of 3.4% was observed in the urban area of Villazon, which indicates that dogs become infected in the rural areas and bring the risk into the city. Lampaya showed a prevalence of 30%. These findings suggest the need to implement strategies for the control of hydatidosis, both in urban and rural areas to avoid the increase and spread of Echinococcosis in the region.
TL;DR: M3 strain could be a potential fungal bioinoculant for production and commercialization of C. nepeta in the aromatic plant market.
Abstract: The aim of this work was to determine the effects of two geographically different strains of Rhizophagus intraradices (M3 and GA5) on the total biomass and essential oil (EO) yield and composition of Calamintha nepeta, with or without phosphorus (P) fertilization, under greenhouse conditions. The plant biomass was not signifi cantly affected by any of the treatments, showing higher values in control plants. Strains had a differential response in their root colonization rates: M3 reduced these parameters while GA5 did not modify them. Both strains affected EO yield in absence of P fertilization: M3 promoted EO yield in C. nepeta plants and GA5 resulted in negative effects. The percentage composition of EO was not signifi cantly modifi ed by either strain or P fertilization. M3 strain could be a potential fungal bioinoculant for production and commercialization of C. nepeta in the aromatic plant market. © 2013 Asociacion Argentina de Microbiologia. Published by Elsevier Espana, S.L. All rights reserved.
TL;DR: Uniserate species predominance was observed in the 1494 strains of Aspergillus section Nigri obtained, whereas none of the strains analysed showed ochratoxin A production in vitro at the detection level of the methodology employed.
Abstract: Fil: Castrillo, Maria Lorena. Universidad Nacional de Misiones. Facultad de Cs.exactas Quimicas y Naturales; Argentina;
TL;DR: Resumen es: Debido al pleomorfismo y la variabilidad cultural que presentan las especies del genero Trichophyton, los metodos de identificacion basados exclusivamente...
Abstract: Due to the pleomorphism and cultural variability displayed by species of the genus Trichophyton, the identification methods based solely on morphological features are usually insufficient for their classification. The goal of the present work was to test a set of phenotypic methods in order to identify fungal isolates that belong to the aforementioned genus. These methods were based on a molecular taxonomic technique used as standard. Clinical isolates (56) were used as samples along with 6 reference strains. Macro and micromorphological studies were performed as well as biochemical and physiological tests such as in vitro hair perforation, nutritional requirements in Trichophyton agar media, urease production and growth on bromocresol purple-milk. solids-glucose (BCP-MS-G) agar. Additionally, PCR fingerprinting using the (GACA)4 primer was employed. As a result of the PCR method, specific profiles were observed for Microsporum canis, Epidermophyton floccosum, Trichophyton rubrum and Trichophyton interdigitale. Identical profiles were obtained for Arthroderma benhamiae y Trichophyton erinacei. Of the total number of clinical isolates, 39 matched the T. rubrum profile while 13 corresponded to A. benhamiae and 4 to T. interdigitale. The most useful phenotypic test to differentiate between T. rubrum and T. mentagrophytes complex strains was alkalinization of the BCP-MS-G medium. Phenotypic tests did not allow differentiation among the T. mentagrophytes complex species. On the other hand, the molecular technique allowed characterization of T. rubrum isolates as well as of those observed in our study and included in the T. mentagrophytes complex: T. interdigitale and Trichophyton sp., the anamorph of A. benhamiae.
TL;DR: Estos son los primeros hallazgos de metalo-β-lactamasas en la institucion, que sugieren una posible diseminacion horizontal del gen blaIMP-8 intra e interespecies.
Abstract: Fil: Togneri, Ana M.. Hospital Interzonal General de Agudos Evita. Laboratorio de Bacteriologia; Argentina
TL;DR: Carobene et al. as mentioned in this paper presented an analysis of the results of a study conducted by the Instituto de Investigaciones Biomedicas En Retrovirus y Sida (IBIES) in Argentina.
Abstract: Fil: Carobene, Mauricio Consejo Nacional de Investcientify Tecnicas Oficina de Coordinacion Administrativa Houssay Instituto de Investigaciones Biomedicas En Retrovirus y Sida; Argentina;
TL;DR: La resistencia a colistina comenzo a emerger, alcanzo el 3 % en los aislados nosocomiales y se mantuvo estable en los anos subsiguientes, debido a la seleccion of las subpoblaciones resistentes en el clon epidemico.
Abstract: Resumen Se estudiaron 64 aislamientos de K. pneumoniae resistentes a colistina recuperados de materiales clinicos de 57 pacientes atendidos entre los anos 2010 y 2012 en el Hospital de Clinicas Jose de San Martin, Universidad de Buenos Aires, con el objetivo de describir las caracteristicas microbiologicas y epidemiologicas y los factores relacionados con la emergencia de estos aislamientos. Se incluyeron en el estudio 54 aislamientos de K. pneumoniae sensibles a colistina contemporaneos a los aislamientos resistentes. La relacion de similitud genetica entre los aislamientos se investigo mediante la tecnica de PCR. El 50 % de los aislamientos resistentes presentaron KPC-2, el 45,3 % BLEE y el 4,7 % restante solo presento resistencia a las aminopenicilinas. Todos los aislamientos portadores de KPC (resistentes o sensibles a colistina), a excepcion de uno, fueron indistinguibles geneticamente, mientras que los portadores de BLEE se agruparon en 7 clones distintos, y se distinguieron de los clones recuperados en los aislamientos sensibles a colistina. El uso previo de colistina se asocio como el principal factor vinculado con la adquisicion de esta resistencia y con la internacion en UCI en los aislamientos sin KPC. A partir del ano 2010 la resistencia a colistina comenzo a emerger, alcanzo el 3 % en los aislados nosocomiales y se mantuvo estable en los anos subsiguientes, debido a la seleccion de las subpoblaciones resistentes en el clon epidemico en los aislamientos productores de KPC, y en los no productores de KPC por dispersion de clones resistentes a colistina.
TL;DR: Preliminary results show that recombinant hemagglutinin expressed from baculovirus elicits a strong antibody response in mice; therefore it could be used as an antigen for subunit vaccines and diagnostic tests.
Abstract: Equine infl uenza virus is a leading cause of respiratory disease in horses worldwide. Disease prevention is by vaccination with inactivated whole virus vaccines. Most current infl uenza vaccines are generated in embryonated hens’ eggs. Virions are harvested from allantoic fl uid and chemically inactivated. Although this system has served well over the years, the use of eggs as the substrate for vaccine production has several well-recognized disadvantages (cost, egg supply, waste disposal and yield in eggs). The aim of this study was to evaluate a baculovirus system as a potential method for producing recombinant equine infl uenza hemagglutinin to be used as a vaccine. The hemagglutinin ectodomain (HA1 subunit) was cloned and expressed using a baculovirus expression vector. The expression was determined by SDS-PAGE and immunoblotting. A high yield, 20 μg/ml of viral protein, was obtained from recombinant baculovirus-infected cells. The immune response in BALB/c mice was examined following rHA1 inoculation. Preliminary results show that recombinant hemagglutinin expressed from baculovirus elicits a strong antibody response in mice; therefore it could be used as an antigen for subunit vaccines and diagnostic tests. © 2013 Asociacion Argentina de Microbiologia. Published by Elsevier Espana, S.L. All rights reserved.
TL;DR: Empleando el antigeno ES/L3 purificado se puede considerar that los sueros that son reactivos, en presencia of una sintomatologia compatible, corresponden a pacientes that fueron o estan parasitados with Toxocara canis.
Abstract: La toxocariosis es una zoonosis causada por la ingestion de huevos infectivos de Toxocara spp. El diagnostico de la enfermedad se basa en la deteccion de anticuerpos en el suero u otros fluidos biologicos. La tecnica serologica mas utilizada es el ELISA, que usa como antigeno los productos de excrecion-secrecion de larvas de tercer estadio (ES/L3). Estos productos antigenicos son glicoproteinas que se originan en los organos secretorios del parasito y no son especificos de especie. Para evaluar la especificidad de la tecnica de ELISA con el antigeno ES/L3, se emplearon sueros de personas con otras helmintiasis y con patologias no parasitarias. Se observo que estos sueros presentaron reactividad entre el 11 y el 70 % de los casos. El Western blot con suero de los mismos pacientes revelo que la glicoproteina que corresponde al triplete de 120 kDa fue la mas inespecifica. Teniendo en cuenta estos resultados y con el proposito de purificar el antigeno se realizo una cromatografia de intercambio ionico. Cuando se analizaron los sueros de los pacientes con diferentes enfermedades parasitarias y no parasitarias con el antigeno ES/L3 purificado, solo fueron reactivos entre un 10 y un 20 % de ellos. La sensibilidad del test de ELISA determinada por el programa Epidat 3. 0 para los dos antigenos fue del 100 %, pero se observaron diferencias en la especificidad: para el antigeno ES/L3 total esta fue del 84 % y para el ES/L3 purificado del 99 %. Empleando el antigeno ES/L3 purificado se puede considerar que los sueros que son reactivos, en presencia de una sintomatologia compatible, corresponden a pacientes que fueron o estan parasitados con Toxocara canis.