Inhibition of astroglial hemichannels prevents synaptic transmission decline during spreading depression.

BACKGROUND: Spreading depression (SD) is an intriguing phenomenon characterized by massive slow brain depolarizations that affect neurons and glial cells. This phenomenon is repetitive and produces a metabolic overload that increases secondary damage. However, the mechanisms associated with the initiation and propagation of SD are unknown. Multiple lines of evidence indicate that persistent and uncontrolled opening of hemichannels could participate in the pathogenesis and progression of several neurological disorders including acute brain injuries. Here, we explored the contribution of astroglial hemichannels composed of connexin-43 (Cx43) or pannexin-1 (Panx1) to SD evoked by high-K+ stimulation in brain slices. RESULTS: Focal high-K+ stimulation rapidly evoked a wave of SD linked to increased activity of the Cx43 and Panx1 hemichannels in the brain cortex, as measured by light transmittance and dye uptake analysis, respectively. The activation of these channels occurs mainly in astrocytes but also in neurons. More importantly, the inhibition of both the Cx43 and Panx1 hemichannels completely prevented high K+-induced SD in the brain cortex. Electrophysiological recordings also revealed that Cx43 and Panx1 hemichannels critically contribute to the SD-induced decrease in synaptic transmission in the brain cortex and hippocampus. CONCLUSIONS: Targeting Cx43 and Panx1 hemichannels could serve as a new therapeutic strategy to prevent the initiation and propagation of SD in several acute brain injuries.

A preclinical mice model of multiple sclerosis based on the toxin-induced double-site demyelination of callosal and cerebellar fibers.

BACKGROUND: Multiple sclerosis (MS) is an irreversible progressive CNS pathology characterized by the loss of myelin (i.e. demyelination). The lack of myelin is followed by a progressive neurodegeneration triggering symptoms as diverse as fatigue, motor, locomotor and sensory impairments and/or bladder, cardiac and respiratory dysfunction. Even though there are more than fourteen approved treatments for reducing MS progression, there are still no cure for the disease. Thus, MS research is a very active field and therefore we count with different experimental animal models for studying mechanisms of demyelination and myelin repair, however, we still lack a preclinical MS model assembling demyelination mechanisms with relevant clinical-like signs. RESULTS: Here, by inducing the simultaneous demyelination of both callosal and cerebellar white matter fibers by the double-site injection of lysolecithin (LPC), we were able to reproduce CNS demyelination, astrocyte recruitment and increases levels of proinflammatory cytokines levels along with motor, locomotor and urinary impairment, as well as cardiac and respiratory dysfunction, in the same animal model. Single site LPC-injections either in corpus callosum or cerebellum only, fails in to reproduce such a complete range of MS-like signs. CONCLUSION: We here report that the double-site LPC injections treatment evoke a complex MS-like mice model. We hope that this experimental approach will help to deepen our knowledge about the mechanisms of demyelinated diseases such as MS.

Cx43 hemichannels and panx1 channels contribute to ethanol-induced astrocyte dysfunction and damage.

BACKGROUND: Alcohol, a widely abused drug, significantly diminishes life quality, causing chronic diseases and psychiatric issues, with severe health, societal, and economic repercussions. Previously, we demonstrated that non-voluntary alcohol consumption increases the opening of Cx43 hemichannels and Panx1 channels in astrocytes from adolescent rats. However, whether ethanol directly affects astroglial hemichannels and, if so, how this impacts the function and survival of astrocytes remains to be elucidated. RESULTS: Clinically relevant concentrations of ethanol boost the opening of Cx43 hemichannels and Panx1 channels in mouse cortical astrocytes, resulting in the release of ATP and glutamate. The activation of these large-pore channels is dependent on Toll-like receptor 4, P2X7 receptors, IL-1ß and TNF-α signaling, p38 mitogen-activated protein kinase, and inducible nitric oxide (NO) synthase. Notably, the ethanol-induced opening of Cx43 hemichannels and Panx1 channels leads to alterations in cytokine secretion, NO production, gliotransmitter release, and astrocyte reactivity, ultimately impacting survival. CONCLUSION: Our study reveals a new mechanism by which ethanol impairs astrocyte function, involving the sequential stimulation of inflammatory pathways that further increase the opening of Cx43 hemichannels and Panx1 channels. We hypothesize that targeting astroglial hemichannels could be a promising pharmacological approach to preserve astrocyte function and synaptic plasticity during the progression of various alcohol use disorders.

Activation of Pannexin-1 channels causes cell dysfunction and damage in mesangial cells derived from angiotensin II-exposed mice.

Chronic kidney disease (CKD) is a prevalent health concern associated with various pathological conditions, including hypertensive nephropathy. Mesangial cells are crucial in maintaining glomerular function, yet their involvement in CKD pathogenesis remains poorly understood. Recent evidence indicates that overactivation of Pannexin-1 (Panx1) channels could contribute to the pathogenesis and progression of various diseases. Although Panx1 is expressed in the kidney, its contribution to the dysfunction of renal cells during pathological conditions remains to be elucidated. This study aimed to investigate the impact of Panx1 channels on mesangial cell function in the context of hypertensive nephropathy. Using an Ang II-infused mouse model and primary mesangial cell cultures, we demonstrated that in vivo exposure to Ang II sensitizes cultured mesangial cells to show increased alterations when they are subjected to subsequent in vitro exposure to Ang II. Particularly, mesangial cell cultures treated with Ang II showed elevated activity of Panx1 channels and increased release of ATP. The latter was associated with enhanced basal intracellular Ca2+ ([Ca2+]i) and increased ATP-mediated [Ca2+]i responses. These effects were accompanied by increased lipid peroxidation and reduced cell viability. Crucially, all the adverse impacts evoked by Ang II were prevented by the blockade of Panx1 channels, underscoring their critical role in mediating cellular dysfunction in mesangial cells. By elucidating the mechanisms by which Ang II negatively impacts mesangial cell function, this study provides valuable insights into the pathogenesis of renal damage in hypertensive nephropathy.

Acute Administration of Calafate (Berberis microphylla) Extract Induces the Expression of Thermogenic Markers and Modulates Gut Microbiota in Mice Fed a High-Fat Chow Diet.

INTRODUCTION: Obesity, characterized by excess adipose tissue, is a major public health problem worldwide. Brown adipose tissue (BAT) and beige adipose tissue participate in thermogenesis through uncoupling protein 1 (UCP1). Polyphenols including those from Calafate (a native polyphenol-rich Patagonian berry), are considered as potential anti-obesity compounds due to their pro-thermogenic characteristics. However, polyphenols are mainly metabolized by the gut microbiota (GM) that may influence their bioactivity and bioavailability. The aim of this study was to determine the impact of dietary administration with a Calafate polyphenol-rich extract on thermogenic activity of BAT and beige adipose tissue and GM composition. METHODS: Eight-week-old C57BL6 mice (n = 30) were divided into 4 groups to receive for 24 weeks a control diet (C), a high-fat diet alone (HF), or high-fat diet supplemented with Calafate extract (HFC) or the same high-fat diet supplemented with Calafate extract but treated with antibiotics (HFCAB) from week 19-20. Administration with Calafate extract (50 mg/kg per day) was carried out for 3 weeks from week 21-23 in the HFC and HFCAB groups. After euthanasia, gene expression of thermogenic markers was analyzed in BAT and inguinal white adipose tissue (iWAT). Transmission electron microscopy was performed to assess mitochondrial morphology and cristae density in BAT. GM diversity and composition were characterized by deep sequencing with the MiSeq Illumina platform. RESULTS: Calafate extract administration had no effect on weight gain in mice fed a high-fat diet. However, it prevented alterations in mitochondrial cristae induced by HFD and increased Dio2 expression in BAT and iWAT. The intervention also influenced the GM composition, preventing changes in specific bacterial taxa induced by the high-fat diet. However, the antibiotic treatment prevented in part these effects, suggesting the implications of GM. CONCLUSION: These results suggest that the acute administration of a Calafate extract modulates the expression of thermogenic markers, prevents alterations in mitochondrial cristae and intestinal microbiota in preclinical models. The study highlights the complex interaction between polyphenols, thermogenesis, and the GM, providing valuable insights into their potential roles in the treatment of obesity-related metabolic diseases.

Hemichannels contribute to mitochondrial Ca2+ and morphology alterations evoked by ethanol in astrocytes.

Alcohol, a toxic and psychoactive substance with addictive properties, severely impacts life quality, leading to significant health, societal, and economic consequences. Its rapid passage across the blood-brain barrier directly affects different brain cells, including astrocytes. Our recent findings revealed the involvement of pannexin-1 (Panx1) and connexin-43 (Cx43) hemichannels in ethanol-induced astrocyte dysfunction and death. However, whether ethanol influences mitochondrial function and morphology in astrocytes, and the potential role of hemichannels in this process remains poorly understood. Here, we found that ethanol reduced basal mitochondrial Ca2+ but exacerbated thapsigargin-induced mitochondrial Ca2+ dynamics in a concentration-dependent manner, as evidenced by Rhod-2 time-lapse recordings. Similarly, ethanol-treated astrocytes displayed increased mitochondrial superoxide production, as indicated by MitoSox labeling. These effects coincided with reduced mitochondrial membrane potential and increased mitochondrial fragmentation, as determined by MitoRed CMXRos and MitoGreen quantification, respectively. Crucially, inhibiting both Cx43 and Panx1 hemichannels effectively prevented all ethanol-induced mitochondrial abnormalities in astrocytes. We speculate that exacerbated hemichannel activity evoked by ethanol may impair intracellular Ca2+ homeostasis, stressing mitochondrial Ca2+ with potentially damaging consequences for mitochondrial fusion and fission dynamics and astroglial bioenergetics.

Acute activation of hemichannels by ethanol leads to Ca2+-dependent gliotransmitter release in astrocytes.

Multiple studies have demonstrated that acute ethanol consumption alters brain function and cognition. Nevertheless, the mechanisms underlying this phenomenon remain poorly understood. Astrocyte-mediated gliotransmission is crucial for hippocampal plasticity, and recently, the opening of hemichannels has been found to play a relevant role in this process. Hemichannels are plasma membrane channels composed of six connexins or seven pannexins, respectively, that oligomerize around a central pore. They serve as ionic and molecular exchange conduits between the cytoplasm and extracellular milieu, allowing the release of various paracrine substances, such as ATP, D-serine, and glutamate, and the entry of ions and other substances, such as Ca2+ and glucose. The persistent and exacerbated opening of hemichannels has been associated with the pathogenesis and progression of several brain diseases for at least three mechanisms. The uncontrolled activity of these channels could favor the collapse of ionic gradients and osmotic balance, the release of toxic levels of ATP or glutamate, cell swelling and plasma membrane breakdown and intracellular Ca2+ overload. Here, we evaluated whether acute ethanol exposure affects the activity of astrocyte hemichannels and the possible repercussions of this phenomenon on cytoplasmatic Ca2+ signaling and gliotransmitter release. Acute ethanol exposure triggered the rapid activation of connexin43 and pannexin1 hemichannels in astrocytes, as measured by time-lapse recordings of ethidium uptake. This heightened activity derived from a rapid rise in [Ca2+]i linked to extracellular Ca2+ influx and IP3-evoked Ca2+ release from intracellular Ca2+ stores. Relevantly, the acute ethanol-induced activation of hemichannels contributed to a persistent secondary increase in [Ca2+]i. The [Ca2+]i-dependent activation of hemichannels elicited by ethanol caused the increased release of ATP and glutamate in astroglial cultures and brain slices. Our findings offer fresh perspectives on the potential mechanisms behind acute alcohol-induced brain abnormalities and propose targeting connexin43 and pannexin1 hemichannels in astrocytes as a promising avenue to prevent deleterious consequences of alcohol consumption.

Genotype analysis to clarify RhD variants in discrepant samples of Chilean population.

Introduction: The D antigen variants are classified as weak, partial, and extremely weak (DEL) and can be differentiated using molecular tests. In Chile, the laboratories of local blood centers do not identify variants of the D antigen, referring them for study to the Reference Laboratory of the Public Health Institute of Chile. So, our aim was to talk about the results of the molecular analysis of variants of the D antigen in samples that had different results in the serological classification. Methods: In the D antigen classification of the Rh system, 479 samples with serological discrepant results were sent for molecular analysis. The Rh phenotype was performed with monoclonal anti-C, anti-c, anti-E, and anti-e antisera by direct agglutination. To find the D antigen, researchers used direct agglutination with monoclonal antisera and indirect antiglobulin testing with the column (gel) agglutination method. Molecular analysis was performed with a polymerase chain reaction with sequence-specific primers (SSP-PCR) and sequencing. Results and discussion: The presence of D antigen variants was confirmed in 332 samples (69.3%), with an initial discrepancy in serological classification. In this group of discrepant samples, the frequency of weak RhD variants was 66% (219/332), that of extremely weak RhD was 28% (93/332), and that of partial RhD was 6% (20/332). The weak variants type 2 (27.4%), type 3 (8.4%), type 48 (8.4%), and type 1 (8.1%) were the next most prevalent variants after RHD*DEL43 (28%). The ccEe (R2r) phenotype was the most frequently detected (38.4%) and is present in 87% of the RHD*DEL43 samples. The E antigen is associated with the presence of this variant. Our analyses give the first description of D antigen variants in Chile. The most common variants are DEL type (RHD*DEL43) and weak (weak type 2), which are linked to the ccDEe (R2r) phenotype. These findings allow us to characterize the variants of the D antigen in Chile and, according to the obtained data, to design strategies for the management of donors, patients, and pregnant women.

Cx43 hemichannels and panx1 channels contribute to ethanol-induced astrocyte dysfunction and damage

Background Alcohol, a widely abused drug, significantly diminishes life quality, causing chronic diseases and psychiatric issues, with severe health, societal, and economic repercussions. Previously, we demonstrated that non-voluntary alcohol consumption increases the opening of Cx43 hemichannels and Panx1 channels in astrocytes from adolescent rats. However, whether ethanol directly affects astroglial hemichannels and, if so, how this impacts the function and survival of astrocytes remains to be elucidated. Results Clinically relevant concentrations of ethanol boost the opening of Cx43 hemichannels and Panx1 channels in mouse cortical astrocytes, resulting in the release of ATP and glutamate. The activation of these large-pore channels is dependent on Toll-like receptor 4, P2X7 receptors, IL-1β and TNF-α signaling, p38 mitogen-activated protein kinase, and inducible nitric oxide (NO) synthase. Notably, the ethanol-induced opening of Cx43 hemichannels and Panx1 channels leads to alterations in cytokine secretion, NO production, gliotransmitter release, and astrocyte reactivity, ultimately impacting survival. Conclusion Our study reveals a new mechanism by which ethanol impairs astrocyte function, involving the sequential stimulation of inflammatory pathways that further increase the opening of Cx43 hemichannels and Panx1 channels. We hypothesize that targeting astroglial hemichannels could be a promising pharmacological approach to preserve astrocyte function and synaptic plasticity during the progression of various alcohol use disorders.

Síndrome de pseudo-Duane secundario a Schwannoma de nervio abducens: Reporte de caso y revisión / Pseudo-Duane syndrome secondary to abducens nerve schwannoma: Case report and review

Reporte de caso de síndrome de pseudo-Duane asociado a schwannoma de nervio abducens y neurofibromatosis tipo 2 (NF2). Este síndrome es raro, caracterizado por limitación en abducción, retracción ocular, disminución de hendidura palpebral en abducción y restricción del recto medial ipsilateral en test de ducción forzada. La NF2 es también una enfermedad infrecuente caracterizada por tumores de sistema nervioso central y periférico. Los schwannomas de nervio abducens son también poco frecuentes, y se presentan comúnmente con diplopia. Se revisan brevemente estas enfermedades. Es el primer caso reportado de pseudo-Duane secundario a schwannoma de nervio abducens y NF2 según nuestro conocimiento.

A pseudo-Duane syndrome case associated with abducens nerve schwannoma and neurofibromatosis type 2 (NF2) is presented. This syndrome is a rare disease characterised by abduction limitation, ocular retraction, narrowing of the palpebral fissure in abduction, and ipsilateral medial rectus restriction on forced duction test. NF2 is also an uncommon disease which is characterised by peripheral and central nervous system tumours. Abducens nerve schwannomas are also uncommon and presents usually as diplopia. A short review of these diseases is given. This is the first case of pseudo-Duane secondary to abducens nerve schwannoma, to our knowledge.

El consumo de un extracto de calafate (Berberis microphylla) modifica marcadores de respuesta inmune en ratones delgados y obesos

RESUMEN La obesidad ha sido identificada como factor de riesgo de severidad de infecciones respiratorias. Apoyar la respuesta inmune en sujetos obesos es de interés. El presente trabajo evaluó el efecto del consumo de un extracto de calafate sobre marcadores de respuesta inmune en ratones delgados y obesos. Ratones C57BL/6J machos fueron expuestos por 82 días a dieta estándar (DE) y alta en grasas (DAG). A un subgrupo de ambos grupos, se les administró 50 y 100 mg [polifenoles totales]/kg peso de animal/día, de extracto, en las últimas dos semanas. Se evaluó expresión génica y secreción de marcadores de respuesta inmune, en tejido pulmonar y plasma. Se observó un efecto del tratamiento con extracto en la expresión de IFN-ϓ. Se observaron efectos inducidos por la DAG y el tratamiento con extracto de manera independiente, en la expresión de IL-12. Se observó un efecto global de la DAG sobre IFN-ϓ plasmático, específicamente una disminución en animales alimentados con DAG. Se observó una interacción entre la dieta y el tratamiento con extracto sobre IL-12 plasmática. El tratamiento utilizado modula marcadores que activan la respuesta inmune ante infecciones respiratorias principalmente de origen viral, en animales delgados y obesos.

ABSTRACT Obesity has been identified as a risk factor for severity of respiratory infections. Thus, the support of the immune response in obese subjects is of interest. The present work evaluated the effect of the consumption of a calafate extract on markers of the immune response in lean and obese mice. Male C57BL/6J mice were exposed for 82 days to a standard or a high-fat diet (HFD). A subgroup of both groups was given 50 and 100 mg [total polyphenols]/kg body weight/day of extract in the last two weeks. Gene expression and secretion of immune response markers were evaluated in lung tissue and plasma. An effect of extract treatment on IFN-ϓ expression was observed. Effects induced by the HFD and treatment with extract were observed independent of the expression of IL-12. An overall effect of the HF diet on plasma IFN-ϓ was observed, specifically a decrease in animals fed the HFD. An interaction between diet and extract treatment was observed over plasma IL-12. The treatment used modulates markers that activate the immune response to respiratory infections, mainly of viral origin, in lean and obese animals.

Caracterización de extractos de piel y hojas de Persea americana Mill. y analisis in vitro de sus potenciales propiedades anti-inflamatorias / Characterization of Persea americana Mill. peels and leaves extracts and analysis of its potential in vitro anti-inflammatory properties

Existe una tendencia mundial de incremento en prevalencia de enfermedades no transmisibles, que se caracterizan por un estado pro-inflamatorio crónico. Por lo tanto, es importante estudiar la relación entre alimentos y salud. La palta (Persea americana), sobresale en la industria por su valor nutricional. El procesamiento de la palta genera gran cantidad de subproductos, que contienen bioactivos con propiedades beneficiosas, como polifenoles. El objetivo del presente trabajo fue caracterizar cuatro extractos de palto (acuoso e hidroalcohólico; de hoja y de cáscara) y analizar sus posibles propiedades anti-inflamatorias in vitro. Fueron determinados polifenoles totales (con el método de Folin­Ciocalteau) y capacidad antioxidante (por FRAP y DPPH) de los extractos. Las propiedades anti-inflamatorias de los extractos fueron determinadas por la liberación de NO y de TNF-, y por la expresión génica de TNF-. Los resultados indican que los extractos hidroalcohólicos presentan más polifenoles (p<0,001) y capacidad antioxidante (p<0,001, por FRAP) que los acuosos. Mas aún, observamos que los extractos hidroalcohólicos de hojas presentaron mayores efectos anti-inflamatorios in vitro, especialmente el hidroalcohólico de hoja en liberación de NO (p<0,001, frente a tratamiento con LPS), acuosos e hidroalcohólicos en liberación de TNF- (p<0,05), y solo los hidroalcohólicos en la expresión de TNF- (p<0,01). En conclusión, los extractos hidroalcohólicos de palto, y especialmente el de hoja, presentan propiedades anti-inflamatorias in vitro que pueden ser consideradas para aplicaciones en mejoría de salud humana.

There is a worldwide trend of increasing prevalence of non-communicable diseases characterized by a chronic inflammatory state. Therefore, it is important to study the relationship between food and health. Avocado (Persea americana) stands out in food industry for its nutritional value. Industrials process of avocado generates a large number of by-products, which contain phytochemical compounds with antioxidant properties, such as polyphenols. The objective of the present research was to characterize four aqueous and hydroalcoholic extracts from avocado leaves and peels and analyze it possible anti-inflammatory properties in vitro. Total polyphenol content (with the Folin-Ciocalteau method) and antioxidant capacity (by FRAP and DPPH) were determined. Extracts inflammatory features were measured by NO and TNF- release, and by TNF- gene expression. Our results indicated that hydroalcoholic extracts present higher total polyphenol content (p<0.001) and antioxidant capacity (p<0.001, by FRAP) than the aqueous ones. Furthermore, we report that hydroalcoholic leaves extract presented greater in vitro anti-inflammatory effect, especially the leave hydroalcoholic regarding NO release (p<0.001, against LPS treatment), aqueous and hydroalcoholics regarding TNF- release (p<0.05), and only the hydroalcoholic in the TNF- gene expression (p<0.01). In conclusion, the avocado hydroalcoholic extracts, and especially from leaves, present in vitro anti-inflammatory features that might be considered for human health improvement applications.

Percepción de riesgo de exposición ocupacional a sílice: construcción y validación de un cuestionario en Chile / Risk perception of occupational exposure to silica: construction and validation of a questionnaire in Chile

Resumen: Introducción: La silicosis es una enfermedad pulmonar progresiva, irreversible, pero potencialmente prevenible. Conocer la percepción de riesgo en trabajadores expuestos a sílice es necesario para intervenir y reducir la incidencia de silicosis y otras enfermedades relacionadas. El objetivo de este estudio fue validar un Cuestionario de Percepción de Riesgo de Exposición Ocupacional a Sílice (CuPREOS) en trabajadores expuestos, en distintas actividades laborales en Temuco, Chile. Material y método: Una etapa de exploración con enfoque fenomenológico/ naturalista permitió conformar categorías de primer y segundo orden, que concluyó en una primera versión del instrumento. Una segunda etapa incluyó análisis factorial exploratorio y confirmatorio. Resultados: Se develaron dos dimensiones subyacentes: a) evidencia de riesgo, en la que el trabajador manifiesta evaluar señales de alarma y b) ausencia de riesgo, en la que sopesa aspectos que contrarrestan las anteriores. Ambas configuran la estructura conceptual que conforma el CuPREOS de 9 ítems/preguntas, con una confiabilidad de 0.84 (alfa Cronbach). Los indicadores del análisis confirmatorio revelan un buen ajuste del mode lo. Discusión: la percepción de riesgo es un constructo que involucra complejidades sociales y culturales, su medición debe ser sencilla y práctica; su conocimiento permitiría decisiones más efectivas en pre vención e intervención.

Abstract: Introduction: Silicosis is a progressive lung disease, irreversible, but potentially preventable. Knowing the perception of risk in workers exposed to silica is necessary to intervene and reduce the incidence of silicosis and other related diseases. The objective of this study was to validate a Questionnaire of risk perception of occupational expo sure to silica (CuPREOS) in exposed workers, in different work activities in Temuco, Chile. Material and method: A stage of explo ration with phenomenological/naturalist approach allowed to create categories of first and second order, which ended in a first version of the instrument. The second stage included exploratory and con firmatory factor analysis. Results: two underlying dimensions were revealed: a) evidence of risk, in which worker states to evaluate signals of alarm and b) absence of risk, in which he weighs aspects that counteract the previous ones. Both set up the conceptual frame work that sustain the CuPREOS of 9 items/questions, with a reliabil ity of 0.84 (Cronbach alfa). The confirmatory analysis indicators show a good fit of the model. Discussion: the perception of risk is a construct involving social and cultural complexities, its measurement should be simple and practical; its knowledge would enable more effective decision-making in prevention and intervention.

Evaluación de la transferencia de adolescentes desde una unidad de cardiología pediátrica a una de adultos / Transfering adolescents from pediatric to adult cardiology units: evaluation

Resumen: Objetivos: evaluar la transferencia de adolescentes desde Cardiología Pediátrica (CP) a Cardiología de Adultos (CA) en el Hospital Dr. Hernán Henríquez de Temuco (HHHT), determinando si recibieron su primera atención en CA en la fecha requerida y si los controles se ajustaron al plazo indicado. Evaluar si la complejidad de la cardiopatía y ruralidad se asocian al cumplimiento en ambos objetivos, en los pacientes sin seguimiento adecuado. Material y Método: revisión de fichas de pacientes atendidos en CP del HHHT que, cumplida la edad requerida, fueron transferidos a CA, entre Octubre 2014 - Julio de 2017. Resultados: De 53 pacientes transferidos de CPCA, 12 (22.6%) tuvo traspaso no efectivo; de ellos, 6 presentaban complejidad moderada-alta (66,6%) y 3 eran rurales (25%). De 28 pacientes ingresados a CA, 14 (50%) tenían seguimiento inefectivo; de ellos 13 (92.6%) tenían cardiopatías de moderada-alta complejidad y 3 (21.5%) provenían de áreas rurales. Conclusiones: la transferencia de CP - CA fue inefectiva en 22.6% de los pacientes; la complejidad de la cardiopatía no se asoció al resultado de la transferencia en este grupo. En CA el seguimiento fue inefectivo en la mitad de los pacientes; de ellos, 92.8% tenían cardiopatías de moderada-alta complejidad, lo que fue estadísticamente significativo respecto de la complejidad en todos los pacientes traspasados. El domicilio no estuvo asociado a la pérdida de pacientes en la transferencia ni en el seguimiento. Estos hallazgos nos permitieron tomar medidas de mejoría en la transferencia y los controles en CA que esperamos mejoren los resultados futuros.

Abstracts: Aim: To evaluate the transfer of adolescents from Pediatric Cardiology (PC) to Adult Cardiology (AC) at Hospital Dr. Hernán Henríquez de Temuco (HHHT). We determined whether they got their first care in AC on the required date and whether controls were performed on the period prescribed. Also, to evaluate whether the complexity of cardiac disease and the patient's place of residence influenced the accomplishment of the objectives, in patients without adequate following. Material and Method: Retrospective review of clinical records of patients that were treated in PC at HHHT who, having the required age were transferred to AC, between October 2014 and July 2017. Results: Of 53 patients that were transferred from PC to AC, 12 (22.6%) had an non effective transfer; 6 of them had moderate to high complexity cardiac lesions (66.6%) and 3 lived in rural areas (25%). Of 28 patients admitted to AC, 14 (50%) had a non effective follow up and 13 (92.8%) had moderate to high complexity forms of heart disease; 3 (21.5%) came from rural areas. Conclusions: Transfer of patients from PC to AC was not effective in 22.6% of patients. The complexity of the disease was not related to the results of transfer in this group. At AC the follow-up was not effective in half the patients; from these, 92.6% had moderate to high complexity heart disease, which was significantly different from the complexity of all patients transferred. The place of residence was not relates to transfer neither to follow-up. These findings allowed us to make improvement in the transfer processes and the follow up at AC.

Virus papiloma humano y Chlamydia trachomatis según número de parejas sexuales y tiempo de actividad sexual en estudiantes universitarias en la Región de La Araucanía, Chile / Human papilloma virus and Chlamydia trachomatis by number of sexual partners and time of sexual activity on university students in the Region of La Araucanía, Chile

Introducción: El virus papiloma humano (VPH) y Chlamydia trachomatis son las infecciones de transmisión sexual (ITS) más frecuentes, en adolescentes y jóvenes, con factores de riesgo: vida sexual activa y múltiples parejas. Chlamydia trachomatis puede favorecer el ingreso de VPH y éste el desarrollo del cáncer cérvico uterino. Ambas infecciones pueden dejar secuelas en la salud sexual y reproductiva. Objetivo: Determinar frecuencias VPH y C trachomatis en estudiantes universitarias asinto-máticas bajo 25 años, asociándolas con número de parejas sexuales (n°PSx) y tiempo de actividad sexual (TASx). Material y Método: Se procesaron 151 muestras/exo y endo cervicales para VPH y C. trachomatis, mediante reacción de polimerasa en cadena convencional y en tiempo real. Resultados: La frecuencia fue: VPH 21,8%, C. trachomatis 11,2% y co-infección 4,6%. De las jóvenes con infección por VPH, 80,6% presentó VPH alto riesgo oncogénico. El n°PSx se asoció fuertemente a VPH. Entre las jóvenes con co-infección VPH/C. trachomatis, 71,4% tenían tres o más PSx. Según TASx, C. trachomatis fue más frecuente (64,7%) entre 3-5 años que VPH. Conclusión: Se observó alta prevalencia de VPH y C trachomatis. Mujeres jóvenes con co-infección VPH/C. trachomatis podrían ser un grupo de alto riesgo con necesidad de mo-nitorear sus infecciones. Es sugerida la implementación de programas universitarios en educación, orientación y prevención en ITS.

Background: Human papilloma virus (HPV) and Chlamydia trachomatis are the most prevalent sexually transmitted infections (STIs), among teenagers and young people, with risk factors: active sex life and multiple partners. Chlamydia trachomatis infection may favor HPV infection and this, the development of cervical cancer. Both infections can lead to consequences on sexual and reproductive health. Objective: To determine frequency of HPV and C. trachomatis in asymptomatic university women less than 25 years, associating them with number of sexual partners (n°SxP) and time of sexual activity (TSxA). Material andMethods: 151 cervical samples for HPV and C. trachomatis, were processed by conventional and in real time reaction polymerase chain. Results: HPV 21, 8%, C. trachomatis 11, 2% and co-infection (HPV/C.trachomatis), 4.6%. Aimong HPV +, 80, 6% showed high risk HPV. The n°SxP was strongly associated with HPV. Aimong young coinfected HPV/C. trachomatis, 71.4% had 3 or more PSx. Chlamydia trachomatis was more frequent (64,7%) that HPV within range of 3-5 years according to the TSxA, Discussion: A high prevalence of HPV and C. trachomatis was observed. Young women with coinfection HPV/C. trachomatis could be a high-risk group need to monitor their infections. It suggests the implementation of university programs in education, counseling and prevention in sexual health.

Comparación de resultados en el diagnóstico de sífilis, por métodos serológicos utilizado por la Red Nacional de Laboratorios de MINSAL, privados y laboratorio nacional de referencia, El Salvador, 2010 ­ 2016 / Comparison of results in the diagnosis of syphilis, by serological methods used by the National Laboratory Network of MINSAL, private and national reference laboratory, El Salvador, 2010 - 2016

Estudio analítico retrospectivo de 15,262 resultados de pruebas diagnósticas serológicas de sífilis utilizadas por Unidades Comunitarias de Salud Familiar, Hospitales de segundo y tercer Nivel y laboratorios Privados anivel de país, del año 2010 al 2016 enviado al laboratorio Nacional de Referencia. Las edades de los pacientes de las muestras evaluadas seencuentra en la media de 39 años; la sífilis afecta en una relación hombre ­mujer de 1; la distribución geográfica del diagnóstico de sífilis es: Metropolitana 57%, Occidental 22%, Para central 8%, Oriental 7% y Central 6%. La prueba RPR posee un valor predictivo positivo de 79.08% y negativo del 55.14%; sensibilidad del 80.41% y especificidad del 53.09%. En 10498 muestras positivas para FTA ­ Abs, poseen un 44.9% RPR con resultado negativo; el valor del índice de Kappa es de 0.339. En El Salvador la situación geográfica de pacientes con mayor diagnóstico de sífilis es la Metropolitana y la edad promedio es 39 años; la relación hombre a mujer es de 1. El análisis de la reagina plasmática rápida (RPR) posee un valor predictivo positivo alto y un valor predictivo negativo bajo para establecer concordancia entre la prueba fluorescente de absorción de anticuerpos anti treponémicos (FTA ­ Abs); Se demostró que el FTA ­ Abs es más específica para el diagnóstico de Sífilis, existiendo una concordancia entre RPR y FTA ­ Abs baja según el valor obtenido por el índice de Kappa

Interacción, sinergia y antagonismo en estudios prospectivos en Epidemiología / Interaction, synergy and antagonism in prospective Epidemiological studies

En Salud Pública existe una creciente conciencia sobre las ventajas de las escalas aditivas para una mejor comprensión del impacto de los factores involucrados en un evento de salud. Es necesario siempre recordar que el concepto de interacción estadística es escala dependiente. En la relación causal entre una respuesta y la presencia de dos o más factores de exposición los conceptos de interacción, sinergia y antagonismo cobran protagonismo. El objetivo de este documento es mostrar una aplicación de los conceptos interacción, sinergia y antagonismo en estudios prospectivos con una mirada de la salud pública. Se presentan tres situaciones que ilustran dichos conceptos. Se utiliza Stata 12 para el ajuste de modelos (log-binomial y Poisson) y estimación de parámetros. Se aportan anexos con conceptos y comandos de Stata usados en los procesos de simulación y estimación de parámetros.

In public health there is a growing appreciation for the advantage of the additive scale to better understand the impacts of factors involved in a health event. It is necessary to always remember that the concept of statistical interaction is scale dependent. In the causal relationship between a response and the presence of two or more factors, the concepts interaction, synergy and antagonism are the key ideas. The aim of this note is to show an application of the concepts interaction, synergy and antagonism in prospective studies from a public health perspective. We present three scenarios that illustrate analyses of interaction, independence, synergy and antagonism. Stata 12 software was used for fitting models (log-binomial model and Poisson) and estimating parameters. Appendixes are provided with concepts and Stata commands used in the processes of simulation and parameter estimation.

Retinopatía del prematuro / Retinal diseases in premature infants

La Retinopatía del Prematuro continúa siendo una importante causa de ceguera en infantes. La terapia con vitamina E aparenta ser de utilidad en la disminución de la severidad en los pacientes afectados. La mejor terapia para el manejo de la Fibroplasia Retrolental Cicatricial es la vitrectomía a cielo abierto