Extracellular vesicles from Listeria monocytogenes-infected dendritic cells alert the innate immune response.

Communication through cell-cell contacts and extracellular vesicles (EVs) enables immune cells to coordinate their responses against diverse types of pathogens. The function exerted by EVs in this context depends on the proteins and nucleic acids loaded into EVs, which elicit specific responses involved in the resolution of infection. Several mechanisms control protein and nucleic acid loading into EVs; in this regard, acetylation has been described as a mechanism of cellular retention during protein sorting to exosomes. HDAC6 is a deacetylase involved in the control of cytoskeleton trafficking, organelle polarity and cell migration, defense against Listeria monocytogenes (Lm) infection and other immune related functions. Here, we show that the protein content of dendritic cells (DCs) and their secreted EVs (DEVs) vary during Lm infection, is enriched in proteins related to antiviral functions compared to non-infected cells and depends on HDAC6 expression. Analyses of the post-translational modifications revealed an alteration of the acetylation and ubiquitination profiles upon Lm infection both in DC lysates and DEVs. Functionally, EVs derived from infected DCs upregulate anti-pathogenic genes (e.g. inflammatory cytokines) in recipient immature DCs, which translated into protection from subsequent infection with vaccinia virus. Interestingly, absence of Listeriolysin O in Lm prevents DEVs from inducing this anti-viral state. In summary, these data underscore a new mechanism of communication between bacteria-infected DC during infection as they alert neighboring, uninfected DCs to promote antiviral responses.

Effect of Rituximab Compared with Natalizumab and Fingolimod in Patients with Relapsing-Remitting Multiple Sclerosis: A Cohort Study.

The objective of this study was to evaluate the clinical files of patients with RRMS who started rituximab (RTX) compared with a second-line treatment (natalizumab (NTZ) or fingolimod (FTY)). This was a historical cohort study. We compared the effect according to the Expanded Disability Status Scale (EDSS) and the number of relapses in RRMS patients receiving these treatments after a mean period of 12 months. We found a statistically significant difference (p < 0.001) when comparing the EDSS scores and the annual relapse rates of patients receiving RTX with those receiving NTZ or FTY. This study is essential for our clinical practice, since patients with limited treatment options represent a challenge with regard to the management of their medical care. However, clinical trials and prospective studies with long follow-up periods are necessary to provide sufficient evidence on the efficacy of RTX and thus include this treatment in the therapeutic profile of patients with MS.

Relación entre intensidad de la ventilación mecánica y agravamiento de la disfunción multiorgánica por la COVID-19 / Relationship between intensity of mechanical ventilation and multiple organ dysfunction worsening by COVID-19

RESUMEN Introducción: La intensidad de la ventilación mecánica está reflejada por la presión de conducción dinámica y el poder mecánico. Es un predictor de lesión pulmonar inducida por el ventilador y está asociada a la mortalidad. Objetivo: Determinar si existe relación entre intensidad de la ventilación mecánica y el ΔSOFA>0 (agravamiento) en los pacientes con la COVID-19 a las 72 horas después de la intubación. Material y Métodos: Grupo de estudio conformado por 35 pacientes diagnosticados con la COVID-19 que estuvieron ventilados por más de 72 horas. Se empleó la prueba de Chi cuadrado (X 2 ) o test exacto de Fisher para comparar variables cualitativas; para las cuantitativas se empleó la prueba t de Student o U de Mann-Whitney. Se realizó una Regresión Logística Binaria Simple para encontrar relación de las variables con ΔSOFA dicotomizada para ΔSOFA≤0 y ΔSOFA>0. La capacidad discriminativa de los modelos se evaluó mediante la Curva ROC. Resultados: Presentaron SOFA>0 21 pacientes (60 %). No se encontraron diferencias significativas de la Presión de Conducción entre ambos grupos (15 vs. 18, U=94.00, z= -1,795, p=0,77). Fueron buenas predictoras de ΔSOFA>0 el Poder Mecánico (OR 3,421 [95 % IC1,510 a 7,750, p=0,003]) y el Volumen Tidal (OR 1,03 [95 % IC 1,012 a 1,068], p=0,005). El Modelo Predictivo de ΔSOFA>0 en función del Poder Mecánico (AUC 0,888 [95 % IC 0,775 a 1], p<0,001) mostró una buena capacidad discriminatoria. Conclusiones: El Poder Mecánico está relacionado con el agravamiento de la disfunción multiorgánica en pacientes sometidos a ventilación mecánica por la COVID-19.

ABSTRACT Introduction: The intensity of mechanical ventilation is reflected by driving pressure and mechanical power. It is a predictor of ventilator-induced lung injury and it can be associated with mortality. Objective: To determine if there is a relationship between intensity of mechanical ventilation and ΔSOFA>0 (worsening) in patients with COVID-19 at 72 h after intubation. Material and Methods: Study group composed of 35 COVID-19 patients who were ventilated for more than 72 hours. Chi-square test (X 2 ) or Fisher's exact test was used to compare qualitative variables; Student t test or Mann-Whitney U test was employed for quantitative ones. A Simple Binary Logistic Regression Model was performed in order to find the relationship between variables and dichotomized ΔSOFA for ΔSOFA≤0 and ΔSOFA>0. The discriminatory capacity of the models was tested by using ROC Curve. Results: A total of 21 patients (60 %) presented ΔSOFA>0 (worsening). No significant differences related to Driving Pressure were found between the two groups (15 vs. 18, U=94,00, z= -1,795, p=0,77). Mechanical Power (OR 3,421 [95 % CI 1,510 a 7,750, p=0,003]) and Tidal Volume (OR 1,03 [95 % CI 1,012 a 1,068], p=0,005) were good predictors of ΔSOFA>0. The Predictive Model of ΔSOFA>0 depending on Mechanical Power (AUC 0,888 [95 % CI 0,775 a 1], p<0,001) showed a good discriminatory capacity. Conclusions: Mechanical Power is related to multi-organ dysfunction worsening in mechanically ventilated patients with COVID-19.

Aprotinin treatment against SARS-CoV-2: A randomized phase III study to evaluate the safety and efficacy of a pan-protease inhibitor for moderate COVID-19.

BACKGROUND: SARS-CoV-2 virus requires host proteases to cleave its spike protein to bind to its ACE2 target through a two-step furin-mediated entry mechanism. Aprotinin is a broad-spectrum protease inhibitor that has been employed as antiviral drug for other human respiratory viruses. Also, it has important anti-inflammatory properties for inhibiting the innate immunity contact system. METHODS: This was a multicentre, double-blind, randomized trial performed in four Spanish hospitals comparing standard treatment versus standard treatment + aprotinin for patients with COVID-19 between 20 May 2020 and 20 October 2021. The primary efficacy outcomes were length of hospital stay and ICU admission. The secondary endpoints were each of the primary efficacy outcomes and a composite of oxygen therapy, analytical parameters and death. Safety outcomes included adverse reactions to treatment during a 30-day follow-up period. Treatment was given for 11 days or till discharge. RESULTS: With almost identical analytical profiles, significant differences were observed in treatment time, which was 2 days lower in the aprotinin group (p = .002), and length of hospital admission, which was 5 days shorter in the aprotinin group (p = .003). The incidence of discharge was 2.19 times higher (HR: 2.188 [1.182-4.047]) in the aprotinin group than in the placebo group (p = .013). In addition, the aprotinin-treated group required less oxygen therapy and had no adverse reactions or side effects. CONCLUSION: Inhaled aprotinin may improve standard treatment and clinical outcomes in hospitalized patients with COVID-19, resulting in a shorter treatment time and hospitalization compared with the placebo group. The administration of aprotinin was safe.

Social life cycle assessment of green methanol and benchmarking against conventional fossil methanol.

Green methanol could play a major role in decarbonising both the chemical and energy sectors. While techno-economic and environmental studies on green methanol following a life-cycle perspective are available, its social implications from a supply-chain standpoint remain largely unexplored. In order to fill this gap, this work presents the first social life cycle assessment of green methanol produced with CO2 directly captured from the air and hydrogen from wind power electrolysis. When compared to conventional methanol from natural gas, the results suggest an unfavourable performance of green methanol under negative social indicators (forced labour, women in the sectoral labour force, health expenditure, social responsibility promotion, and fair salary) due to the increased supply-chain complexity of the green system. In contrast, green methanol would outperform its conventional counterpart in terms of sectoral contribution to economic development, a positive social indicator which would benefit from the increase in working hours. Besides future consideration of a higher number of positive indicators and potential improvements in country- and sector-specific risk levels towards high-quality social and working conditions, an enhanced social life-cycle performance of green methanol requires technical improvements to reduce the high demand for energy inputs and equipment across its supply chain. Acknowledging decarbonisation as the actual driver of green methanol deployment, future social studies are suggested to focus on the comparison of renewable alternatives for its production and the effect of social regulations.

Inmunoglobulinas por vía intravenosa: una alternativa terapéutica a tener en cuenta en el paciente trasplantado renal con COVID-19 / Intravenous immunoglobulins: A therapeutic alternative to consider in kidney transplant patients with COVID-19

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Efficacy and safety of alendronic acid in the treatment of osteoporosis in children.

OBJECTIVES: to describe the efficacy and safety of the off-label use of alendronate in the treatment of osteoporosis in children and adolescents. METHOD: a retrospective study (2008-2014) of all patients under 18 years who were dispensed alendronate for this indication. The criteria for initiating treatment were: bone mineral density with a Z-score ≤ -2.5 SD, a past history of bone fractures without a previous traumatism, and persistent pain. The variables collected were: demographic, treatment-related, clinical. and safety data. The treatment was considered to be effective when there was an increase in bone mineral density up to a Z-score > -2.5 SD. RESULTS: a total of 12 patients, 8 of them male, with a mean age of 11 years (± 3 SD), were treated with alendronate. After a mean time of treatment of 2.15 years (± 1.2 SD), there was an increase in bone mineral density in all patients, 9 of which achieved a Z-score > -2.5 SD, so the drug was considered effective in 75% of cases. No patient had bone fractures or expressed adverse effects during treatment. CONCLUSIONS: alendronate increased bone mineral density and was well tolerated in all patients, therefore it could be considered as a therapeutic option in the treatment of osteoporosis in children.

Objetivos: describir la efectividad y seguridad del uso de acido alendronico en el tratamiento de la osteoporosis en ninos y adolescentes, en condiciones distintas a las autorizadas en la ficha tecnica. Métodos: estudio retrospectivo (2008-2014) de todos los pacientes menores de 18 anos a los que se dispenso acido alendronico para esta indicacion. Los criterios para iniciar tratamiento fueron: densidad mineral osea con puntuacion Z-score ≤ -2,5 DE, antecedentes de fracturas oseas sin traumatismo previo y dolor persistente. Las variables recogidas fueron: demograficas, de tratamiento, clinicas y de seguridad. Se considero efectividad del tratamiento al aumento de la densidad mineral osea hasta obtener Z-score > -2,5 DE. Resultados: un total de 12 pacientes, 8 varones, con una media de edad de 11 anos (} 3 DE), fueron tratados con acido alendronico. Tras un tiempo medio de tratamiento de 2,15 anos (} 1,2 DE), se produjo aumento de la densidad mineral osea en todos los pacientes, 9 de los cuales obtuvieron Z-score > -2,5 DE, por lo que el farmaco se considero efectivo en el 75% de los casos. Ningun paciente presento fracturas oseas ni manifesto efectos adversos durante el tratamiento. Conclusiones: el acido alendronico incremento la densidad mineral osea y se tolero bien en todos los pacientes, por lo que se podria considerar como opcion terapeutica en el tratamiento de la osteoporosis infantil.

Efficacy and safety of alendronic acid in the treatment of osteoporosis in children / Efectividad y seguridad del ácido alendrónico en el tratamiento de la osteoporosis infantil

Objectives: to describe the efficacy and safety of the off-label use of alendronate in the treatment of osteoporosis in children and adolescents. Method: a retrospective study (2008-2014) of all patients under 18 years who were dispensed alendronate for this indication. The criteria for initiating treatment were: bone mineral density with a Z-score ≤-2.5 SD, a past history of bone fractures without a previous traumatism, and persistent pain. The variables collected were: demographic, treatment-related, clinical. and safety data. The treatment was considered to be effective when there was an increase in bone mineral density up to a Z-score >-2.5 SD. Results: a total of 12 patients, 8 of them male, with a mean age of 11 years (± 3 SD), were treated with alendronate. After a mean time of treatment of 2.15 years (±1.2 SD), there was an increase in bone mineral density in all patients, 9 of which achieved a Z-score >-2.5 SD, so the drug was considered effective in 75% of cases. No patient had bone fractures or expressed adverse effects during treatment. Conclusions: alendronate increased bone mineral density and was well tolerated in all patients, therefore it could be considered as a therapeutic option in the treatment of osteoporosis in children (AU)

Objetivos: describir la efectividad y seguridad del uso de ácido alendrónico en el tratamiento de la osteoporosis en niños y adolescentes, en condiciones distintas a las autorizadas en la ficha técnica. Métodos: estudio retrospectivo (2008-2014) de todos los pacientes menores de 18 años a los que se dispensó ácido alendrónico para esta indicación. Los criterios para iniciar tratamiento fueron: densidad mineral ósea con puntuación Z-score ≤-2,5 DE, antecedentes de fracturas óseas sin traumatismo previo y dolor persistente. Las variables recogidas fueron: demográficas, de tratamiento, clínicas y de seguridad. Se consideró efectividad del tratamiento al aumento de la densidad mineral ósea hasta obtener Z-score >-2,5 DE. Resultados: un total de 12 pacientes, 8 varones, con una media de edad de 11 años (± 3 DE), fueron tratados con ácido alendrónico. Tras un tiempo medio de tratamiento de 2,15 años (± 1,2 DE), se produjo aumento de la densidad mineral ósea en todos los pacientes, 9 de los cuales obtuvieron Z-score >-2,5 DE, por lo que el fármaco se consideró efectivo en el 75% de los casos. Ningún paciente presentó fracturas óseas ni manifestó efectos adversos durante el tratamiento. Conclusiones: el ácido alendrónico incrementó la densidad mineral ósea y se toleró bien en todos los pacientes, por lo que se podría considerar como opción terapéutica en el tratamiento de la osteoporosis infantil (AU)

Circuit mechanisms underlying motor memory formation in the cerebellum.

The cerebellum stores associative motor memories essential for properly timed movement; however, the mechanisms by which these memories form and are acted upon remain unclear. To determine how cerebellar activity relates to movement and motor learning, we used optogenetics to manipulate spontaneously firing Purkinje neurons (PNs) in mouse simplex lobe. Using high-speed videography and motion tracking, we found that altering PN activity produced rapid forelimb movement. PN inhibition drove movements time-locked to stimulus onset, whereas PN excitation drove delayed movements time-locked to stimulus offset. Pairing either PN inhibition or excitation with sensory stimuli triggered the formation of robust, associative motor memories; however, PN excitation led to learned movements whose timing more closely matched training intervals. These findings implicate inhibition of PNs as a teaching signal, consistent with a model whereby learning leads first to reductions in PN firing that subsequently instruct circuit changes in the cerebellar nucleus.

A novel synaptic vesicle fusion path in the rat cerebral cortex: the "saddle" point hypothesis.

We improved freeze-fracture electron microscopy to study synapses in the neuropil of the rat cerebral cortex at ∼2 nm resolution and in three-dimensions. In the pre-synaptic axon, we found that "rods" assembled from short filaments protruding from the vesicle and the plasma membrane connects synaptic vesicles to the membrane of the active zone. We equated these "connector rods" to protein complexes involved in "docking" and "priming" vesicles to the active zone. Depending on their orientation, the "rods" define two synaptic vesicle-fusion paths: When parallel to the plasma membrane, the vesicles hemi-fuse anywhere ("randomly") in the active zone following the conventional path anticipated by the SNARE hypothesis. When perpendicular to the plasma membrane, the vesicles hemi-fuse at the base of sharp crooks, called "indentations," that are spaced 75-85 nm center-to-center, arranged in files and contained within gutters. They result from primary and secondary membrane curvatures that intersect at stationary inflection ("saddle") points. Computer simulations indicate that this novel vesicle-fusion path evokes neurotransmitter concentration domains on the post-synaptic spine that are wider, shallower, and that reach higher average concentrations than the more conventional vesicle fusion path. In the post-synaptic spine, large (∼9× âˆ¼15 nm) rectangular particles at densities of 72±10/ µm2 (170-240/spine) match the envelopes of the homotetrameric GluR2 AMPA-sensitive receptor. While these putative receptors join clusters, called the "post-synaptic domains," the overwhelming majority of the rectangular particles formed bands in the "non-synaptic" plasma membrane of the spine. In conclusion, in the neuropil of the rat cerebral cortex, curvatures of the plasma membrane define a novel vesicle-fusion path that preconditions specific regions of the active zone for neurotransmitter release. We hypothesize that a change in the hybridization of the R-SNARE synaptobrevin from parallel to antiparallel swings the synapse into this novel vesicle-fusion path.

Design and construction of a modular low-cost epifluorescence upright microscope for neuron visualized recording and fluorescence detection.

BACKGROUND: One of the limitations when establishing an electrophysiology setup, particularly in low resource settings, is the high cost of microscopes. The average cost for a microscope equipped with the optics for infrared (IR) contrast or microfluorometry is $40,000. We hypothesized that optical elements and features included in commercial microscopes are not necessary to IR video-visualize neurons or for microfluorometry. NEW METHOD: We present instructions for building a low-cost epifluorescence upright microscope suitable for visualized patch-clamp recording and fluorescence detection using mostly catalog-available parts. RESULTS: This microscope supports applications such as visualized whole-cell recording using IR oblique illumination (IR-OI), or more complex applications such as microfluorometry using a photodiode. In both IR-OI and fluorescence, actual resolution measured with 2-µm latex beads is close to theoretical resolution. The lack of movable parts to switch configurations ensures stability when doing intracellular recording. COMPARISON WITH EXISTING METHODS: The low cost is a significant advantage of this microscope compared to existent custom-built microscopes. The cost of the simplest configuration with IR-OI is ∼$2000, whereas the cost of the configuration with epifluorescence is ∼$5000. Since this design does not use pieces discarded from commercial microscopes, it is completely reproducible. CONCLUSIONS: We suggest that this microscope is a viable alternative for doing in vitro electrophysiology and microfluorometry in low-resource settings. Characteristics such as an open box design, easy assembly, and low-cost make this microscope a useful instrument for science education and teaching for topics such as optics, biology, neuroscience, and for scientific "hands-on" workshops.

"Conocimiento, actitud y aceptación acerca de la medicina alternativa, en los médicos-profesores de la Escuela de Medicina de la Universidad Industrial de Santander" / "Knowledge, attitude and acceptance of alternative medicine by physician-professors at the faculty of medicine at Universidad Industrial de Santander"

Introducción: en el proceso de institucionalización de la enseñanza de la medicina alternativa y terapias complementarias en escuelas de medicina es importante conocer las actitudes de los médicos-docentes, encargados de la formación de los futuros profesionales de la salud. Objetivo: conocer las actitudes de los profesionales médicos sobre la medicina alternativa y terapias complementarias en su desempeño como docentes en la escuela de medicina de la Universidad Industrial de Santander, sede Bucaramanga. Metodología: estudio observacional descriptivo con enfoque cuantitativo, mediante encuesta transversal. Resultados: 112 docentes respondieron la encuesta; 67 no lo hicieron y 5 no se contactaron. El 72,3 % de la población tiene conocimiento nulo sobre medicina alternativa y terapias complementarias. Los sentimientos de los encuestados son positivos o neutros hacia cada una de las disciplinas y se manifiestan por el uso personal de la medicina alternativa y terapias complementarias, en la recomendación a familiares y amigos, el buscar capacitarse en esta disciplina, discutir con sus pacientes sobre la posibilidad de manejo con ésta medicina, referir pacientes a éstos profesionales, practicar y enseñar éstas disciplinas, además, estimular a sus estudiantes a capacitarse en dicha ciencia. Conclusiones: el grado de conocimiento de la población estudiada frente a la medicina alternativa y terapias complementarias determina la actitud que se tiene frente a cada una de las disciplinas, como la Homeopatía, la Terapia Neural, la Medicina Tradicional China, la medicina Ayurveda, la terapia con filtros, los ejercicios terapéuticos, la naturopatía, la herbología y las terapias manuales. Salud UIS 2012; 44 (1): 45-55.

Introduction: in the process of institutionalizing alternative medicine and complementary therapies teaching at medicine schools is important to know the attitudes of medic-teachers in charge of forming the future health care professionals. Objective: To know the attitudes of the medicine professionals about alternative medicine and complementary therapies in their job as professional medicine professors at the Medicine School at Universidad Industrial de Santander, in Bucaramanga. Methodology: observational-descriptive study supported by quantitative techniques. Results: 112 professors answered the survey, 67 didn't and 5 couldn't be reached. 72.3% of the study population had no knowledge of alternative medicine and complementary therapies. The feelings of those that answered the survey where neutral to good towards the different disciplines and are manifested by the personal use, recommendation to family and friends, looking for training, discussing about and referring patients, as well as suggesting the sciencie field to their students. Conclusions: the degree of knowledge of the study population about alternative medicine and complementary therapies determines their attitude and how they feel about the different disciplines. Salud UIS 2012; 44 (1): 45-55.

Antimicrobial therapy and local toxicity of intraventricular administration of vancomycin in a neonate with ventriculitis.

Infection is the most common complication and cause of failure of cerebrospinal fluid (CSF) shunt devices used to control hydrocephalus. A male newborn was admitted for treatment of congenital occlusive hydrocephalus by means of a ventriculo-peritoneal shunt. A day later, the skin area around the site of insertion of ventriculo-peritoneal catheter was red and edematous. Intravenous ceftazidime and vancomycin were initiated. The shunt was removed but the external ventricular drain was preserved. Blood and CSF cultures showed Enterococcus faecalis sensitive to vancomycin, ciprofloxacin and gentamicin, but resistant to ampicillin. Intraventricular administration of vancomycin 10 mg/24 h was initiated through the external ventricular drain. Before the first dose of vancomycin intraventricularly, CSF levels were 19 mg/dL as a result of administration. On the third day of intraventricular dosing, vancomycin levels in CSF reached 388 mg/dL and protein levels were 1160 mg/dL. On the fifth day of intraventricular treatment the patient had clinically improved and was bacteriologically cured. However, in CSF, protein levels were 3300 mg/dL and vancomycin levels 201 mg/dL. In an attempt to prevent high and potentially toxic levels in CSF, the intraventricular dose of vancomycin should be individualized according to clinical response, bacteriological cultures, vancomycin levels in CSF, and surrogate markers of neurotoxicity, that is, eosinophilia and high protein levels in CSF.

Primary central nervous system non-Hodgkin lymphoma in childhood presenting as bilateral optic neuritis.

INTRODUCTION: Primary central nervous system lymphoma is a very rare condition in pediatric patients. CASE REPORT: We describe the case of a 10-year old girl who presented with acute bilateral vision impairment. At the time of presentation, the only positive finding was optic disk swelling, and the brain MRI scan was normal. Seventeen months later, she developed a large-cell non-Hodgkin lymphoma in the brain, with no evidence of neoplasia elsewhere. Immunodeficiencies and Epstein-Barr virus infection could not be demonstrated. The patient was successfully treated with a combination of cyclophosphamide, etoposide, vincristine, methotrexate, and cytarabine, plus intrathecal chemotherapy. Craniospinal irradiation was not used. OUTCOME: The patient's condition is still in remission 68 months after completing the treatment. CONCLUSION: This case is the only non-Hodgkin lymphoma with primary central nervous system location treated in our institution in the last 10 years and represents less than 0.5% of our non-Hodgkin lymphoma series. Due to its rare occurrence, not much is known about the clinical features and treatment outcome of primary central nervous system lymphoma in pediatric patients.

[Exposure to group B Streptococcus among Mexican women in reproductive age]. / Exposición a Estreptococo del grupo B en mujeres mexicanas en edad reproductiva.

OBJECTIVE: To assess the prevalence of IgG antibodies against Group B streptococci (GBS) among women of reproductive age in Mexico. MATERIAL AND METHODS: Serum specimens were drawn from 15 to 40 year-old women, representative of all regions and socioeconomic levels of the country. The sample was randomly selected from Banco Nacional de Sueros (National Sera Bank); serum samples were collected during a national seroepidemiologic survey conducted in 1987-1988. The assays for standardization and for evaluation of seroprevalence were carried out at the Hospital de Pediatría del Centro Médico Nacional Siglo XXI (Children's Hospital) Instituto Mexicano del Seguro Social (IMSS) (Mexican Institute of Social Security) from January to November 1995. IgG antibodies against group B antigen were studied with an enzyme-linked immunosorbent assay (ELISA) developed in our lab. Group B antigen was produced and purified from the reference strain GBS 110. RESULTS: A total of 2669 serum samples were studied; 2405 were positive to anti-group B antigen IgG antibodies, for a seroprevalence of 90.2%. No differences in prevalence were found among the different age groups or among the different states of the country. CONCLUSIONS: The high seroprevalence of antibodies against GBS suggests that young women in Mexico are commonly exposed to GBS infection.

Exposición a Estreptococo del grupo B en mujeres mexicanas en edad reproductiva / Exposure to group B Streptococcus among Mexican women in reproductive age

OBJECTIVE: To assess the prevalence of IgG antibodies against Group B streptococci (GBS) among women of reproductive age in Mexico. MATERIAL AND METHODS: Serum specimens were drawn from 15 to 40 year-old women, representative of all regions and socioeconomic levels of the country. The sample was randomly selected from Banco Nacional de Sueros (National Sera Bank); serum samples were collected during a national seroepidemiologic survey conducted in 1987-1988. The assays for standardization and for evaluation of seroprevalence were carried out at the Hospital de PediatrÝa del Centro MÚdico Nacional Siglo XXI (Children's Hospital) Instituto Mexicano del Seguro Social (IMSS) (Mexican Institute of Social Security) from January to November 1995. IgG antibodies against group B antigen were studied with an enzyme-linked immunosorbent assay (ELISA) developed in our lab. Group B antigen was produced and purified from the reference strain GBS 110. RESULTS: A total of 2669 serum samples were studied; 2405 were positive to anti-group B antigen IgG antibodies, for a seroprevalence of 90.2. No differences in prevalence were found among the different age groups or among the different states of the country. CONCLUSIONS: The high seroprevalence of antibodies against GBS suggests that young women in Mexico are commonly exposed to GBS infection.

Infecciones en trasplante en pediatría: Parte II: infecciones virales, parasitarias e infecciones en trasplante de médula ósea y xenotrasplante / Infection in pediatric transplant recipients: Part II: viral and parasitosis infections and infections in children with bone marrow trasplantation or xenotrasplant

Las infecciones virales y parasitarias en pacientes trasplantados tienen una morbilidad y mortalidad asociadas importantes y representan un alto costo en la atención médica de dichos padecimientos, ya que la mayoría requiere manejo hospitalario. La infección por citomegalovirus (CMV) se vigila en la actualidad mediante pruebas que permiten separar a los pacientes trasplantados que padecen infecciones activas de los que tienen infecciones latentes, como la antigenemia pp65 de CMV en leucocitos. La enfermedad linfoproliferativa por el virus de Epstein-Barr puede ser tratada en algunos casos sólo mediante la disminución de la inmunosupresión, pero en otros a través de la administración de quimioterapia. Las infecciones que ocurren en quienes reciben trasplante de médula ósea requieren un enfoque particular dada la neutropenia inicial con la que cursan y la enfermedad de injerto contra huésped en trasplantes alogénicos. Las infecciones en el xenotrasplante representan un campo de investigación interesante y menos explorado que las infecciones en otro tipo de trasplantes.

Infecciones en trasplante en pediatría. Parte I.Infecciones bacterianas y fúngicas en órgano sólido / Infections in pediatric transplant recipients. Part 1. Solid-organ bacterial and funagal infections

Las infecciones en niños trasplantados requieren un estudio particular debido a su compromiso inmunológico. En la Ciudad de México se realizan trasplantes renales, de hígado y de médula ósea en la población infantil, cada vez en mayor número. Lo anterior obliga a conocer las infecciones que los afectan con la finalidad de realizar mejor prevención de éstas. El éxito del procedimiento quirúrgico también puede verse afectado por la presencia de infecciones graves. La vigilancia de las infecciones que afectan a esta población infantil debe realizarse con métodos que permitan identificar la presencia de infecciones activas para poder brindar un tratamiento anticipado y prevenir el desarrollo de enfermedad. En esta revisión se presentan los aspectos más relevantes en la prevención y el manejo de las infecciones bacterianas y fúngicas en niños trasplantados.