Design of Two Multiplex PCR Assays for Serotyping Shigella flexneri.

Shigella flexneri is a major health problem in developing countries. There are 19 serotypes recognized based on O-antigen structure and its typing is important for epidemiological purposes. However, the diversity of serotypes and the difficulties presented by phenotypic serotyping, for example, unavailable antisera for less common antigens, require the implementation of molecular techniques. In this study, we developed two multiplex PCR assays targeting the O-antigen synthesis genes and the O-antigen modification genes, for the rapid identification of S. flexneri serotypes 1/7, 2, 4, 5, and 6 (PCR A) and serotype 7 and group antigenic factors (3,4; 6; 7,8; E1037) (PCR B). A total of 73 S. flexneri strains representing 18 serotypes, except serotype 1d, were used in the study. Specific amplification patterns were obtained for each of the different serotypes. All strains tested had concordant results with phenotypic and genotypic serotyping; therefore, its implementation in the microbiology clinical laboratory will significantly improve S. flexneri serotyping.

AA479 antiserum: new reagent for the serotype characterization of atypical variants of Shigella flexneri.

Shigella flexneri is divided into 13 serotypes based on the combination of antigenic determinants present in the O-antigen. A new O-antigen modification with phosphoethanolamine has been identified. The presence of this antigenic determinant (called E1037) is recognized by monoclonal antibody MASF IV-1. Given the increasing incidence of these new variants and the difficulty in supplying the monoclonal antibody to our country, we produced a polyclonal antiserum (AA479) through immunization with a S. flexneri Xv strain. The antiserum specificity was assessed by slide agglutination against isolates from clinical cases and a culture collection representing all Shigella serotypes. The results obtained demonstrated a 100% correlation between AA479 absorbed antiserum and monoclonal antibody MASF IV-1. The availability of AA479 antiserum in every public hospital in Argentina will allow us to identify atypical S. flexneri isolates in order to strengthen Shigella surveillance in our country and to compare with global epidemiological data.

Antisuero AA479: nuevo reactivo para la serotipificación de variantes atípicas se Shigella flexneri / AA479 antiserum: new reagent for the serotype characterization of atypical variants of Shigella flexneri

Shigella flexneri is divided into 13 serotypes based on the combination of antigenic determinants present in the O-antigen. A new O-antigen modification with phosphoethanolamine has been identified. The presence of this antigenic determinant (called E1037) is recognized by monoclonal antibody MASF IV-1. Given the increasing incidence of these new variants and the difficulty in supplying the monoclonal antibody to our country, we produced a polyclonal antiserum (AA479) through immunization with a S. flexneri Xv strain. The antiserum specificity was assessed by slide agglutination against isolates from clinical cases and a culture collection representing all Shigella serotypes. The results obtained demonstrated a 100% correlation between AA479 absorbed antiserum and monoclonal antibody MASF IV-1. The availability of AA479 antiserum in every public hospital in Argentina will allow us to identify atypical S. flexneri isolates in order to strengthen Shigella surveillance in our country and to compare with global epidemiological dat

Shigella flexneri se divide en al menos 13 serotipos sobre la base de la combinación de determinantes antigénicos presentes en el antígeno O. Se identificó una nueva modificación del antígeno O con fosfoetanolamina. La presencia de este determinante antigénico (denominado E1037) es reconocida por el anticuerpo monoclonal MASF IV-1. Teniendo en cuenta la incidencia creciente de estas nuevas variantes y la dificultad en la provisión del anticuerpo monoclonal para nuestro país, se elaboró un antisuero de tipo policlonal (AA479) mediante la inmunización con un cultivo de S. flexneri Xv. La especificidad del antisuero se evaluó por aglutinación en lámina con aislamientos clínicos y cultivos de colección, con lo que quedaron representados todos los serotipos de Shigella. Los resultados obtenidos demostraron una correlación del 100% entre el antisuero AA479 absorbido y el anticuerpo monoclonal MASF IV-1. La disponibilidad del antisuero AA479 en todos los hospitales públicos de Argentina permitirá identificar los aislamientos atípicos de S. flexneri; de esta forma se podrá fortalecer la vigilancia de Shigella en nuestro país y comparar con los datos epidemiológicos a nivel global

Successful live birth from oocytes after more than 14 years of cryopreservation.

OBJECTIVE: To report a birth of a healthy girl after long-term oocyte cryopreservation by slow cooling in sodium depleted medium. DESIGN: Clinical application. SETTING: University Affiliated, Private IVF center. PATIENT: A 38-year-old woman received embryos from IVF by intracytoplasmic sperm injection (ICSI) with her own oocytes that were cryopreserved by slow freezing in a low-sodium medium 14 years and 6 months before, when she was 24 years old. MAIN OUTCOME MEASURE(S): Survival, fertilization, cleavage, clinical pregnancy and delivery. RESULT(S): From six metaphase-II oocytes thawed, two survived, one was fertilized after ICSI and a cleaving embryo was transferred on day 3. A single term pregnancy was achieved, ending with the delivery of a healthy girl. CONCLUSION(S): Cryopreservation after slow freezing in a sodium depleted medium maintained the developmental competence of oocytes after long-term storage and resulted in a successful live birth. As far as is known, this case represents, up to date, the longest storage period of cryopreserved human oocytes resulting in a live birth.

Endoscopic ultrasound-guided fine needle aspiration: predictive factors of accurate diagnosis and cost-minimization analysis of on-site pathologist.

AIMS: To evaluate a) new diagnoses by endoscopic ultrasound guided real-time fine-needle aspiration (EUS-FNA) compared with EUS alone; b) the predictive factors for an accurate EUS-FNA diagnosis, and c) the cost-effectiveness of the presence of an on-site cytopathologist. PATIENTS AND METHODS: Demographic data, ultrasonographic characteristics, technical information on EUS-FNA and cytological results were prospectively collected in 213 patients. The gold standard used was pathological examination or clinical follow-up. Operating characteristics of EUS-FNA, multivariate analysis, and a cost-minimization study of on-site evaluation were performed with these variables. RESULTS: Samples were obtained from a total of 262 lesions: extramural masses (n = 115), lymph nodes (n = 96), cysts (n = 40) and intramural lesions (n = 11). The overall accuracy of EUS-FNA was 89% (234/262 lesions). The accuracy of EUS in discriminating between malignant and benign disease was 92% but 105 lesions (40% of the total) were classified as indeterminate. The addition of FNA to EUS allowed almost all lesions (89%) to be diagnosed with an accuracy of 90%. The only variable independently associated with an incorrect diagnosis was intramural location of the target lesion. The effectiveness of EUS-FNA in the complete series progressively increased, reaching a plateau in the fourth pass. The presence of an attendant cytopathologist was cost-effective. CONCLUSIONS: EUS-FNA allows diagnosis of most lesions classified as indeterminate by EUS alone. The only factor independently associated with low accuracy is intramural location of the lesion. The availability of an on-site cytopathologist is cost-effective.

Efectividad de un antihistamínico-descongestionante en el catarro común en niños: un estudio aleatorizado placebo controlado / Effectiveness of a antihistaminic descongestionant at the vulgar catarrh at childrens: a aleatorizate placebo

Objetivos del estudio: 1) Determinar la efectividad de una combinación antihistamínico-descongestionante para el alivio sintomático del catarro común no complicado, 2)Estimar la proporción de padres, cuyos hijos sufren de catarro, que creen que se requiere medicación para tratar los síntomas, 3) Determinar la frecuencia de efectos adversos de las drogas anticatarrales. Diseño: prueba aleatoria, controlada, tres grupos experimentales (droga, placebo y no tratamiento). Población: 99 niños con diagnóstico de catarro común, edad entre 6-36 meses, asignados aleatoriamente a grupo droga (n=33), placebo (n=33) y no tratamiento (n=33). La droga antihistamínico-descongestionanate y el placebo fueron dados por vía oral por 48 horas después de la admisión al estudio, a dosis de 0.2 mg/Kg/dosis de bronfeniramina para la droga, y a 2 gotas/kg/dosis para el placebo, tres veces al día por 48 horas

Patologia de las lesiones cardiacas provocadas por la corriente ablativa de radiofrecuencia en un modelo experimental / Pathology of the cardiac lesions induced by radiofrequency ablation in an experimental model

La ablación transcatéter por radiofrecuencia es utilizada crecientemente en el tratamiento de diversas taquiarritmias. El objeto de este estudio es determinar su patología lesional. Catorce ratas Wistar (peso medio 300 g) fueron sometidas a descargas de un generador de 700 KHz de onda senoidal pura inmodulada. Tres ratas recibieron descargas epicárdicas por toracotomía. Sus corazones fueron representativos de la etapa "aguda". Las ll restantes recibieron descargas a través delimplante percutáneo de alambres de tungsteno. Sus corazones fueron estudiados entre l y 4 semanas de la lesión (etapa "crônica"). Las piezas se fijaron "in toto" en formol 10 por ciento tamponado (pH7). Cortes seleccionados fueron teñidos con hematoxilina-eosina y tricrómico de Mallory. Otros fueron prefijados en glutaraldehido 3 por ciento y post-fijados en tetróxido de osmio, deshidratados e incluidos en Polybed 812. Secciones ultrafinas se tiñeron con acetato de uranilo y citrato de plomo, para microscopía electrónica. Las lesiones "agudas" evidenciaron pequeñas áreas de necrosis de coagulación bien delimitadas por zonas de carbonización y hemorragia. El miocardio vecino mostró una o dos filas de lesiones celulares moderadas consistentes en homogeneización citoplasmática y aumento de las bandas de contractura. Las lesiones "crónicas" mostraron tejido de granulación con infiltrados mononucleares y vasos de neoformación rodeando un área de necrosis central. Cuanto más "vieja" la lesión, mayor el número de fibroblastos y colágeno maduro. La ultraestructura evidenció cambios irreversibles en los bordes lesionales, con edema citosólico e intermiofibrilar, bandas de contractura y ruptura de crestas mitocondriales. Las lesiones de radiofrecuencia son limitadas, poco profundas y de bordes netos, y estas características las hacen casi ideales para la ablación subendocárdica transcatéter de pequeñas zonas arritmogénicas.