Desarrollo de lenguaje en niños con implante coclear en centro terciario de salud: serie clínica / Language development in children with cochlear implant at a tertiary health care center: clinical series

Resumen Introducción: Desde la década de los 90, los implantes cocleares han progresado desde aplicaciones experimentales a un uso clínico estandarizado en niños con pérdida auditiva severa y profunda. Las investigaciones han producido cambios en la tecnología de los implantes y ha dado lugar a la expansión de los candidatos a implante para incluir a los niños menores de 2 años de edad. El objetivo principal de la implantación coclear pediátrica es facilitar el desarrollo del lenguaje hablado. A pesar de los avances en la tecnología de implantes y los cambios en el manejo de la pérdida auditiva, los resultados de lenguaje en niños son todavía muy variables, participando de este proceso tanto el tratamiento oportuno, la red familiar y nivel socioeconómico entre algunos de ellos. Objetivo: Describir resultados de niños menores 6 años sometidos a cirugía de implante coclear en un centro terciario de salud. Material y método: Estudio longitudinal de cohorte retrospectivo, análisis a 99 pacientes implantados en centro terciario de salud desde inicio programa en 1994 a 2015. Resultados: 99 pacientes, 57% hombres 43% mujeres, edad promedio implantación 16,3 meses. 54,8% casos origen congénito no especificado o prematurez. En 74,4% se objetivó presencia de lenguaje auditivo verbal. El nivel socioeconómico (NSE) mostró asociación con no desarrollo de lenguaje (p =0,009) evidenciando que pacientes de bajo NSE 20% no desarrolla lenguaje. La variable discapacidad asociada (p <0,001) y la variable NSE (p =0,036) se asociaron de manera independiente a lenguaje de señas o no desarrollo de lenguaje oral. Conclusión: Los implantes cocleares ofrecen una opción en la rehabilitación auditiva en hipoacusia sensorio neural profunda, para candidatos de todo el espectro de edad, sin embargo los resultados dependen en gran medida del entorno en el que se utilizan los implantes cocleares.

ABSTRACT Introduction: Since the 90s, cochlear implantation has progressed from experimental to standard clinical practice for children with severe and profound hearing loss. Research has produced changes in implant technology and has led to the expansion of implant candidacy to include children younger than 2 years of age. The primary goal of pediatric cochlear implantation is to facilitate spoken language development. Despite the advances in implant technology and the changes to the management of hearing loss, language outcomes for children are still highly variable, participating in this process both timely treatment, the family network and socio economic level among others. Aim: describe outcomes of patients younger than 6 years undergoing cochlear implant surgery in a tertiary care center. Material and method: retrospective longitudinal cohort study, 99 patients implanted in a tertiary health center since the program's inception in 1994 to 2015 was analyzed. Results: 99 patients, 57 % men 43 % women, average age of implantation 16.3 months. 54.8 % of cases were congenital or prematurity. In 74.4 % they had auditory verbal language. Socioeconomic status (SES) showed association with the lack of language development (p =0.009) demonstrating that low SES patients (20%) do not develop language. The disability associated variable (p <0.001) and the SES variable (p =0.036) were independently associated with sign language or no oral language development. Conclusions: Cochlear implants offer an option for hearing rehabilitation in profound hearing loss, for candidates of all ages, however the results depend largely on the environment in which cochlear implants are used.

Resultados del programa de implantes cocleares de Clínica Las Condes a 20 años de su inicio: serie clínica 1994-2015 / Cochlear implant program results in Clinica Las Condes 20 years since the beginning: clinical series 1994-2015

RESUMEN Introducción: La hipoacusia sensorioneural es la tercera causa de discapacidad en Chile, con incidencia en recién nacidos de 1 a 3 casos cada 1.000 recién nacidos vivos, y prevalencia en adultos de hasta 70%, siendo muchos casos susceptibles de ser tratados mediante implante coclear. Objetivo: Describir resultados de los pacientes sometidos a cirugía de implante coclear en Clínica Las Condes (CLC). Material y método: Estudio longitudinal de cohorte retrospectiva, se analizaron a 237 pacientes implantados en Clínica Las Condes desde 1994 al año 2015. Resultados: Se analizan 237 pacientes, 106 mujeres (44,7%) y 131 hombres (55,3%). El 65,5% de los pacientes se implantaron entre los 2-6 años de vida. Las etiologías más frecuentes fueron hipoacusia congénita no sindrómica (45,9%), genética tardía (11,8%) y posmeningitis (11,4%). Se encontró asociación significativa entre promedio tonal de la palabra (PTP) y presencia de malformación coclear (p =0,008). Sólo 9,9% de los pacientes presentaron otra discapacidad asociada a la hipoacusia. La tasa de reimplante fue 16,3% y sólo la variable malformación coclear se asoció a ella (p =0,016). Conclusión: El implante coclear es una herramienta beneficiosa en pacientes hipoacúsicos que no se benefician de otros dispositivos auditivos ofreciendo la posibilidad de reinsertarlos social y laboralmente con bajo riesgo quirúrgico y alta tasa de éxito.

ABSTRACT Introduction: Sensorineural hearing loss is the third leading cause of disability in Chile, with incidence in infants 1 to 3 cases per 1,000 newborn and prevalence in adult up to 70%, with many cases that can be treated with cochlear implant. Aim: to describe outcomes of our series of patients undergoing cochlear implant surgery at Clinica Las Condes (CLC). Material and method: Retrospective longitudinal cohort study, 237 patients implanted in our center since 1994 to 2015 were analyzed. Results: 237 patients, 106 women (44.7%) and 131 men (55.3%) received a cochlear implant during this period. 65.5% of patients were implanted between 2-6 years of age. The most common etiologies were; non-syndromic congenital deafness (45.9%), late genetic onset (11.8%) and meningitis (11.4%). A significant association between the average pure tone average and presence of cochlear malformation (p =0.008) was demonstrated. Only 9.9% of patients had other disabilities associated with hearing loss. Re-implantation rate was 16.3% and only the variable cochlear malformation was associated to it (p =0.016) Conclusions: The cochlear implant provides clear benefits to patients with hearing impairment who do not benefit from other hearing devices offering the possibility of social and labor reintegrating, with low surgical risk and high success rate.

Programa de screening auditivo neonatal universal: experiencia de más de 10 años / Universal newborn hearing screening program: experience over 10 years

Introducción: La implementación de Programas de Evaluación Auditiva Neonatal (PEAN) eficientes permite mejorar la pesquisa de recién nacidos (RN) con hipoacusia congénita (HC), facilitando una intervención temprana. Objetivo: Describir los resultados del PEAN universal llevado a cabo por el Departamento de Otorrinolaringología de Clínica Las Condes. Material y método: Estudio descriptivo, retrospectivo. Se estudiaron los resultados del programa y las variables: género, edad de diagnóstico, edad gestational al parto y factores de riesgo asociados al desarrollo de HC en RN evaluados entre mayo 2001 y junio 2012. Resultados: Fueron evaluados 18.224 RN. Reprobaron esta evaluación 809 RN (4,43%). Se diagnostican 70 HC (56% varones, 44% mujeres), con una incidencia general estimada de 3-4 cada 1.000 RN en este establecimiento. 54,3% correspondió a HC unilaterales y 45,7% a bilaterales, siendo éstas en 90% leves a moderadas. El factor de riesgo mayormente asociado fue presencia de anomalías craneofaciales en 38,5% seguido de un peso nacimiento <1.500 gr. en 10%. Discusión y conclusiones: Es imperativo la realización de PEAN universales para diagnosticar a la población general susceptible a desarrollar HC y más aún en aquellas poblaciones donde se concentran los factores de riesgo.

Introduction: Efficient universal newborn hearing screening program (UNHSP) Implementation allows the inquest improvement of newborns with congenital hearing loss (CHL), facilitating an early intervention. Aim: To describe the results of the UNHSP carried out by the Department of Otorhinolaryngology of Clinica Las Condes. Material and method: Descriptive, retrospective study. We studied the program results and variables: sex, diagnosis age, birth age in weeks and risk factors associated with development CHL in newborns evaluated between May, 2001 and June, 2012. Results: 18.224 newborns were evaluated. 809 reproved this evaluation (4.43%). We diagnosed 70 CHL (56% males, 44% women), with an incidence estimated of 3-4 cases every 1.000 newborns. 54.3% corresponded to unilateral CHL and 45.7% bilateral, 90% of this CHL were slight to moderate. The presence of craniofacial anomalies was the main associate risk factor in 38,5% followed by a weight birth <1.500 gr. in a 10%. Discussion and conclusions: Is imperative the accomplishment of UNHSP to diagnose the population at risk of developing CHL and even more in those populations where the risk factors are concentrated.

Estrategias para mejorar el seguimiento del Programa de Evaluación Auditiva Neonatal Universal / Strategies to improve follow-up of the Universal Newborn Hearing Screening Program

Introducción: El Programa de Evaluación Auditiva Neonatal (PEAN) en Clínica Las Condes se inició el 2001 y ha evaluado más de 18.000 niños. Nuestro desafío actual es lograr que aquellos cuyo examen se encuentre alterado reciban precozmente evaluación y derivación oportuna. Objetivo: Analizar el impacto de estrategias para mejorar el seguimiento del programa por medio de la reducción del porcentaje de pérdida de seguimiento. Material y método: Durante 2010 se implementaron nueve estrategias para mejorar el seguimiento del PEAN. Mediante una cohorte retrospectiva se evaluaron los resultados de PEAN 12 meses previos y posteriores a la implementación de éstas. Resultados: El 2009 se evaluaron 1.797 niños, completaron el protocolo 71,1%, perdiéndose en el seguimiento 28,9%. El 2011, posterior a la implementación de las medidas, se evaluaron 1.823 niños, completaron el protocolo 85,1%, perdiéndose en el seguimiento sólo 14,9%. La diferencia del porcentaje de pérdidas de seguimiento entre el2009y 2011 fue de 13.87% (p: 0.042). Discusión y conclusiones: Es necesario descubrir las causas de pérdida de seguimiento para establecer estrategias que ayuden a mejorar estas cifras y permitir que todo niño pesquisado sea diagnosticado a tiempo. La implementación de estrategias como las planteadas en este trabajo son una forma práctica y efectiva para mejorar el seguimiento del PEAN.

Introduction: The Newborn Hearing Screening Program (NHSP) at Clinica Las Condes began in 2001 and up to date, has evaluated over 18.000 children. Our current challenge is to achieve that children with referred screening, receive early evaluation and intervention. Aim: To analyze the Impact of strategies to Improve program's follow-up reducing the percentage of follow-up losses. Material and method: During 2010 nine NHSP strategies were implemented to improve the follow-up. By a retrospective cohort NHSP's results were evaluated 12 months previous and after the implementation of these strategies. Results: In 20091.797 children were evaluated, 71,1% completed the protocol, with 28,9% lost in the follow-up. In 2011, after strategies' implementation, 1.823 children were evaluated, 85,1 %, completed the protocol and only 14,9 % were lost in the follow-up. The difference in the percentage lost between 2009 and 2011 was 13.87 % (p: 0.042). Discussion and conclusions: It is necessary to discover the reasons of loss to follow-up, in order to establish strategies that may allow every referred child to be diagnosed in time. Implementation of strategies like the raised in this investigation is a practical and effective way to improve the follow-up of NHSP.

Recombinant streptokinase suppositories in the treatment of acute haemorrhoidal disease. Multicentre randomized double-blind placebo-controlled trial (THERESA-2).

AIM: A four-arm multicentre randomized double-blind placebo-controlled trial was undertaken to assess the effect and safety of suppositories containing recombinant streptokinase (rSK) at two dose levels (100,000 IU and 200,000 IU) with sodium salicylate (SS) compared with placebo and SS for the treatment of acute haemorrhoidal disease. METHOD: Patients with acute symptoms of haemorrhoids were randomized to four treatment groups: (I) placebo, (II) SS, (III) SS + rSK 100,000 IU and (IV) SS + rSK 200,000 IU per suppository. Inpatient treatment was by four suppositories given every 6 h to discharge at 24 h. Evaluations were made at the time of discharge (24 h) and at 3, 5 and 20 days later. The main end-point was the degree of relief of pain, oedema and reduction in the size of the lesion by 90% on day 5. Adverse events and the occurrence of anti-SK antibodies were also determined. RESULTS: Eighty patients were included. Respective response rates in the four groups were 16%, 30%, 25% and 52%. In the last group there was a significant difference (36.8%) compared with control (95% CI 7.0-58.4%). The time to response was significantly shorter (median 5 days) in the 200,000 IU rSK group with respect to the others. There were no adverse events attributable to the treatment. No increase in anti-SK antibodies was detected 20 days after treatment. CONCLUSION: Suppositories with 200,000 IU rSK showed a significant improvement in symptoms of acute haemorrhoids, with an adequate safety profile.

Diversity and composition of dengue virus type 2 in Venezuela.

Dengue is a mosquito-borne disease caused by four closely related dengue virus (genus Flavivirus)serotypes (DENV-1­4). The clinical outcomes vary from mild febrile illness to life-threatening haemorrhagic manifestations. DENVs are endemic in the tropics and subtropics globally and currently no specific treatment or vaccines are available. In Venezuela, the American-Asian genotype of DENV-2 is the most prevalent and has been associated with severe disease outcomes.We aimed to follow-up the molecular epidemiology of DENV-2 in Venezuela to investigate if the evolution of the virus has remained the same throughout time or if the same dynamics documented in Brazil (hyperendemic co-circulation) also occurred. The results show that whereas the epidemiology of DENV in several endemic areas is characterized by serotype replacements through time, in Venezuela the American-Asian genotype DENV-2 has evolved into several genetic lineages and has remained in hyperendemic co-circulation with the other serotypes.

Uso de corticoide intralesional en histiocitosis de langerhans crónica focal: reporte de un caso / Use of intralesional corticoids in focal chronic langerhans cell histiocytosis: A case report

El término Histiocitosis de células de Langerhans (HCL) comprende a un grupo de enfermedades que son el resultado de una alteración a nivel del sistema fagocítico mononuclear. En función de los hallazgos clínicos la HCL, se clasifican en tres grupos por fines pronósticos y terapéuticos: 1.- Crónica Focal, por lo general lesión solitaria de un hueso, sin afectación de otros órganos ni partes blandas (ex Granuloma Eosinófilo); 2.- Crónica Diseminada, (ex Hand-Schuller-Christian); 3.- Aguda Diseminada (ex Letterer-Siwe). La etiología de este grupo de lesiones permanece incierta, aunque se han propuesto: infección, inflamación y reacciones inmunológicas. Presentamos el caso clínico de un paciente de género femenino, de 12 años de edad, que consulta por aumento de volumen en la zona del ángulo mandibular derecho con un mes de evolución, no doloroso. Se realiza ortopantomografía y TAC, observando destrucción de cortical vestibular y lingual. Se realiza la biopsia, se somete a estudio inmunohistoquímico, dando el diagnóstico de HCL Crónica Focal, fue tratado con Triancinolona de 40 mg (Kenalog - 40) en 2 dosis, con control de 3 años y sin recidivas a la fecha.

The term Histiocitosis of Langerhans's cells (LCH) covers a group of diseases that are the result of an alteration to the mononuclear phagocyte system. According to the clinical findings, the HCL is classified in three groups for predictable and therapeutic purposes: 1.- Focal Chronic, in general a lone injury of a bone, without affecting other organs or soft parts (Ex-Eosinophilic granuloma); 2.-Spread Chronic, (ex-Hand-Schuller-Christian); 3.- Spread Acute (ex-Letterer-Siwe).The etiology of this group of injuries remains unknown, eventhough it has been proposed: infection, inflammation and immunological reactions. Here, we present a clinical case: A 12-year-old female patient that consults for increase of volume in mandibular right back area, with a one month of evolution, not painful. Panoramic radiograph and TAC images are showing, observing destruction of vestibular and lingually bone. The biopsy was submitted to immunohystochemical study, giving the diagnosis of Chronic Focal LCH, it was treated with Triancinolona 40 mg (Kenalog - 40) in 2 doses, after 3 years of following up there is not signs of recurrence at the date.

Shared information in stationary states of stochastic processes.

We present four estimators of the shared information (or interdepency) in ground states given that the coefficients appearing in the wave function are all real non-negative numbers and therefore can be interpreted as probabilities of configurations. Such ground states of Hermitian and non-Hermitian Hamiltonians can be given, for example, by superpositions of valence bond states which can describe equilibrium but also stationary states of stochastic models. We consider in detail the last case, the system being a classical not a quantum one. Using analytical and numerical methods we compare the values of the estimators in the directed polymer and the raise and peel models which have massive, conformal invariant and nonconformal invariant massless phases. We show that like in the case of the quantum problem, the estimators verify the area law with logarithmic corrections when phase transitions take place.

Evaluación auditiva neonatal universal: revisión de 10.000 pacientes estudiados / Universal newborn hearing screening: review of 10. 000 evaluations

Introducción: La hipoacusia es la discapacidad congénita más frecuente entre los recién nacidos vivos y su diagnóstico precoz e intervención temprana permiten un desarrollo social y educacional normal en el niño. Objetivo: Revisar la experiencia del programa de evaluación auditiva universal de nuestra institución. Material y método: Estudio retrospectivo de todos los recién nacidos evaluados entre mayo de 2001 y diciembre de 2007. El tamizaje auditivo se realizó mediante emisiones otoacústicas y potenciales evocados auditivos automatizados. Resultados: En el período de estudio fueron evaluados 10.095 recién nacidos, pesquisándose 30 casos de hipoacusia congénita. La mayoría de éstas (80 por ciento) correspondieron a hipoacusias leves a moderadas. El diagnóstico de hipoacusia estaba confirmado antes de los 3 meses de vida en el 88,5 por ciento de los casos. Se calculó una tasa de hipoacusia congénita de 2,8 por cada 1.000 recién nacidos en sala cuna y de 21 por cada 1.000 recién nacidos de alto riesgo (UTI neonatal). Discusión: En nuestros resultados destacan la amplia cobertura lograda y la precocidad del diagnóstico, lo que ha permitido realizar una oportuna intervención y rehabilitación.

Introduction: Hearing loss is the most common congenital disability, and its early recognition and treatment is important for the normal social and educational development of the child. Aim: To review the results of the universal newborn hearing screening program at our institution. Material and method: Retrospective study of all newborns examined between May 2001 and December 2007. Hearing screening was carried out by otoacoustic emissions and automated auditory brainstem potentials. Results: 30 cases of congenital hearing loss were detected among the 10.095 newborns that were examined during the study period. Most hearing impairments (80 percent) were mild to moderate. Diagnosis of hearing loss was confirmed by the age of 3 months in88.5 percent> of the patients. We estimated a congenital hearing loss rate of 2.8 cases in 1000 newborns at the nursery, and of 21 cases In 1000 high-risk newborns (neonatal ICU). Discussion: From our results, it is noteworthy the high coverage and the early diagnosis achieved, which enabled us to make timely interventions and rehabilitation.

New vaccines require potent adjuvants like AFPL1 and AFCo1.

Neisseria meningitidis B proteoliposome (AFPL1 when used as adjuvant) and its derivative-Cochleate (AFCo1) contain immunopotentiating and immunomodulating properties and delivery system capacities required for a good adjuvant. Additionally, they contain meningococcal protective antigens and permit packaging of other antigens and pathogen-associated molecular patterns (PAMP). Consequently, we hypothesized that they would function as good vaccine adjuvants for their own antigens and also for non-related antigens. AFPL1 is a detergent-extracted outer membrane vesicle of N. meningitidis B transformed into AFCo1 in calcium environment. Both are produced at Finlay Institute under good manufacture practices (GMP) conditions. We show their exceptional characteristics: combining in the same structure, the potentiator activity, polarizing agents and delivery system capacities; presenting multimeric protein copies; containing multiprotein composition and multi and synergistic PAMP components; acting with incorporated or co-administrated antigens; inducing type I IFN-gamma and IL-12 cytokines suggesting the stimulation of human plasmocytoid precursor and conventional dendritic cells, respectively, inducing a preferential Th1 immune response with TCD4(+), TCD8(+), cross-presentation and cytotoxic T-lymphocyte (CTL) in vivo responses; and functioning by parenteral and mucosal routes. AFPL1-AFCo1 protective protein constitutions permit per se their function as a vaccine. In addition to Phase IV Men BC vaccine, AFPL1 has ended the preclinical stage in an allergy vaccine and is concluding the preclinical stage of a nasal meningococcal vaccine. In conclusion, AFPL1 and AFCo1 induced signal 1, 2 and 3 polarizing to a Th1 (including CTL) response when they acted directly as vaccines or were used as adjuvants with incorporated or co-administered antigens by parenteral or mucosal routes. Both are very promising adjuvants.

Development and characterization of a murine monoclonal antibody specific for the P1.15 PorA proteins from vaccine strain B:4,7:P1.19,15 of Neisseria meningitidis.

Neisseria meningitidis isolates are conventionally classified by serosubtyping, which characterizes the reactivities of the PorA outer membrane protein variable-region epitopes with monoclonal antibodies (MAbs). New murine hybridomas, secreting specific MAbs against PorA of N. meningitidis serogroup B, were generated using conventional hybridoma procedures. Using outer membrane protein as antigen, we obtained two positive clones, and one of them we characterized. This MAb reacted, on whole-cell enzyme-linked immunosorbent assay (ELISA) and immunoblotting, only with strain subtype P1.15 and its IgG2b isotype. This MAb demonstrated bactericidal activity against the homologous strain in the presence of human complement.

Formulation in tablets of a cholera whole cells inactivated vaccine candidate.

Licensed as well as candidate cholera vaccines available at the present requires the dose preparation (included buffer) at the moment of application. The aim of this work was to evaluate the presentation in oral tablets of an inactivated cholera vaccine to avoid that inconveniences during application. We have therefore compared inactivated cultures of Vibrio cholerae with tablets formulation vaccine. We obtained that antigenic activity (ELISA) and immunogenicity in animal model (ELISA and vibriocidal tests) of V. cholerae inactivated cell remained unaltered in the final tablet formulation. The results suggest that the oral tablet formulation could be a useful pharmaceutical form in order to produce a new and affordable cholera vaccine.

Process development for a Cuban cholera vaccine based on the attenuated strain Vibrio cholerae 638.

Genetically modified Vibrio cholerae strain 638 (biotype El Tor, serotype Ogawa) has previously been shown to be immunogenic in animal models and in human trials. Our objective in the work reported herein was to describe the process development methods for the production of the 638 attenuated cholera vaccine. Cell seed bank, culture of biomass, lyophilization and final formulation were processes were developed. The results show kinetics of culture that fulfils a logistical model. The microbiological properties, colonizing capability, immunogenicity and non-toxigenicity of the final product were indistinguishable from the properties of the working seed lot. We conclude that the non-reactogenic, immunogenic and protective strain 638 is robust and can withstand the fermentation processes required for large-scale production of a vaccine.

Producción de juveniles de erizo rojo Strongylocentrotus franciscamus (Echinodermata: Echinoidea) en Baja California, México / Juvenile production of the red sea urchin Strongylocentrotus franciscanus (Echinodermata: Echinoidea) in Baja California, Mexico

The red sea urchin Strongylocentrotusfranciscanus (Agassiz 1863) is harvested commercially in Baja California, Mexico, since 1970; however, in the last ten years the capture per unit effort (CPUE) has decreased from 310 kg/fishing unit/day to 120 kg/fishing unit/day. For this reason, actions were taken to develop a culture technology allowing massive production of juveniles for re-stocking natural populations or for growing them commercially. We summarize some of the basic studies and main achievements in this effort. In Baja California, considerably faster larval development (approximately 21 days) has been attained than in the US northwest coast (62 days). Spawning of red sea urchins was routinely induced with KCI while egg fertilization was performed using a 100,000-sperm/ml solution. Six microalgae species were tested and Rhodomonas sp. produced the best larval development. The mean survival rate at the end of the larval period was 25%, but results varied widely with bactch. From the feed ratios tested, best results were obtained using 7000 cel/ml during the first week of larval development, followed by 10,000 cel/ml during the second and 15,000 cel/ml during the third week. KCl proved the most consistent metamorphic inducer, regularly yielding metamorphosis percentages higher than 90%. Metamorphosis was considered complete when the functional jaw that juveniles use for first benthic feeding appeared (as soon as 20 days after induction). With this method several thousands of red sea urchin juveniles were produced. They reached up to 1.5 mm in size during the first 50 days of culture after metamorphosis, showing the great potential for mass production of this species in the laboratory

[Juvenile production of the red sea urchin Strongylocentrotus franciscanus (Echinodermata: Echinoidea) in Baja California, Mexico]. / Producción de juveniles de erizo rojo Strongylocentrotus franciscanus (Echinodermata: Echinoidea) en Baja California, México.

The red sea urchin Strongylocentrotusfranciscanus (Agassiz 1863) is harvested commercially in Baja California, Mexico, since 1970; however, in the last ten years the capture per unit effort (CPUE) has decreased from 310 kg/fishing unit/day to 120 kg/fishing unit/day. For this reason, actions were taken to develop a culture technology allowing massive production of juveniles for re-stocking natural populations or for growing them commercially. We summarize some of the basic studies and main achievements in this effort. In Baja California, considerably faster larval development (approximately 21 days) has been attained than in the US northwest coast (62 days). Spawning of red sea urchins was routinely induced with KCI while egg fertilization was performed using a 100,000-sperm/ml solution. Six microalgae species were tested and Rhodomonas sp. produced the best larval development. The mean survival rate at the end of the larval period was 25%, but results varied widely with bactch. From the feed ratios tested, best results were obtained using 7000 cel/ml during the first week of larval development, followed by 10,000 cel/ml during the second and 15,000 cel/ml during the third week. KCl proved the most consistent metamorphic inducer, regularly yielding metamorphosis percentages higher than 90%. Metamorphosis was considered complete when the functional jaw that juveniles use for first benthic feeding appeared (as soon as 20 days after induction). With this method several thousands of red sea urchin juveniles were produced. They reached up to 1.5 mm in size during the first 50 days of culture after metamorphosis, showing the great potential for mass production of this species in the laboratory.

Imágenes del abdomen postoperatorio / Images of the postoperated abdomen

Los estudios radiológicos no se han desarrollado de manera rutinaria como forma de vigilar los diferentes procedimientos quirúrgicos del tubo digestivo, sino con el fin de valorar la integridad de los órganos o para investigar las complicaciones postoperatorias de la cirugía. La adecuada interpretación de las imágenes implica tener el profundo co¬nocimiento, tanto de las diferentes técnicas quirúrgicas como del tiempo de evolución postoperatorio, para, en un momento dado, determinar las posibles complicaciones. Son muchas las técnicas empleadas para facilitar una interpretación correcta, de las cuales las más utilizadas son la radiografía convencional (simple o con medios de contraste), la ecografía y la escanografía.

Lesiones del tubo digestivo superior por ingestión de sustancias cáusticas / Upper digestive tract lesions secondary to ingestion of caustic substances

La ingesta de cáusticos es un problema de salud pública que puede presentarse en niños o en población adulta. En el primer grupo suelen ser lesiones accidentales, mientras que en el segundo usualmente se asocian con intentos de suicidio. En este artículo se revisan la fisiopatología de las lesiones del tubo digestivo superior por ingesta de cáus¬ticos, el mecanismo de acción de los agentes cáusticos ácidos y básicos sobre la mucosa digestiva, así como los hallazgos radiográficos en el esófago y el estómago.

Molecular epidemiology of dengue virus type 3 in Venezuela.

During the past 40 years, dengue haemorrhagic fever and dengue shock syndrome (DHF/DSS) have emerged in humans, with approximately 3 million cases reported and over 58 000 deaths. Dengue virus serotypes 1, 2 and 4 (DENV-1, -2 and -4) have been co-circulating in Venezuela for at least the past 10 years, causing minor or major outbreaks of dengue fever (DF) and DHF/DSS. The first recorded outbreak due to DENV-3 in Venezuela dates to 1964 and the virus then seems to have disappeared. However, DENV-3 re-appeared recently (in July, 2000) in Venezuela after 32 years of absence and produced a prolonged major outbreak, which, by the end of 2001, involved 83 180 cases of dengue, mostly DF (92 %). Previous phylogenetic studies revealed that the DENV-3 circulating during the 1960s Latin American outbreak was a genotype V virus. To gain a better understanding of the nature of the current epidemic, the complete sequence was determined of the envelope (E) gene of 15 Venezuelan DENV-3 viruses isolated during 2000 and 2001 from patients presenting with different disease severity. Sequence data were used in phylogenetic comparisons with global samples of DENV-3. Analysis revealed that the strain circulating in Venezuela is closely related to isolates that were previously present in Panama and Nicaragua in 1994 and since then have spread through Central American countries and Mexico. This study also confirms previous reports showing that the DENV-3 strain currently circulating in the Americas is related to the strain that caused DHF epidemics in Sri Lanka and India in 1989-1991 (genotype III). Finally, no evidence of the re-emergence of the strain that circulated in Venezuela in the late 1960s and 1970s (genotype V) was found.