Patologías del niño inmigrante en la Unidad de Cuidados Intensivos: actualización / Pathologies of the immigrant child in the Intensive Care Unit: update

Resumen: Cada vez es más frecuente la atención médica en la Unidad de Cuidados Intensivos (UCI) de niños o adolescentes inmigrantes como también de aquellos nacidos en nuestro país con padres en tal condición. Esto ha ocasionado, en la actualidad, que el equipo de salud se deba enfrentar con problemas diagnósticos derivados del escaso conocimiento de condiciones genéticas propias de esta población y/o el desarrollo de diversas patologías infrecuentes en nuestro país, algunas resultantes de su condi ción sanitaria. En esta revisión se abordan diversos aspectos de la patología hematológica, infecciosa, parasitaria, respiratoria y cardiovascular, todos tópicos relevantes de conocer durante su estadía en la UCI. Es un deber del equipo de salud actualizarse sobre patologías de baja prevalencia en nuestro país, algunas de ellas muy poco conocidas hasta hace una década, pero que, actualmente, están cada vez más presentes en las UCI del sistema de salud público chileno.

Abstract: It is increasingly common to provide medical care in the Intensive Care Unit (ICU) for immigrant children and adolescents as well as those born in Chile with parents in such condition. Currently, this has caused that the health team has to face diverse infrequent pathologies in our country and/ or diagnostic problems derive from the poor knowledge of genetic conditions of this population, some resulting from their health conditions. This review addresses several aspects of hematological, infectious, parasitic, respiratory, and cardiovascular pathologies, all relevant topics to know during their stay in the ICU. It is a duty of the health team to be updated on pathologies of low prevalence in our country, some of them very little known until a decade ago, but which are currently increasingly present in the ICUs of the Chilean public health system.

[Pathologies of the immigrant child in the Intensive Care Unit. Update]. / Patologías del niño inmigrante en la Unidad de Cuidados Intensivos. Actualización.

It is increasingly common to provide medical care in the Intensive Care Unit (ICU) for immigrant children and adolescents as well as those born in Chile with parents in such condition. Currently, this has caused that the health team has to face diverse infrequent pathologies in our country and/ or diagnostic problems derive from the poor knowledge of genetic conditions of this population, some resulting from their health conditions. This review addresses several aspects of hematological, infectious, parasitic, respiratory, and cardiovascular pathologies, all relevant topics to know during their stay in the ICU. It is a duty of the health team to be updated on pathologies of low prevalence in our country, some of them very little known until a decade ago, but which are currently increasingly present in the ICUs of the Chilean public health system.

Relationships among Bone Quality, Implant Osseointegration, and Wnt Signaling.

A variety of clinical classification schemes have been proposed as a means to identify sites in the oral cavity where implant osseointegration is likely to be successful. Most schemes are based on structural characteristics of the bone, for example, the relative proportion of densely compact, homogenous (type I) bone versus more trabeculated, cancellous (type III) bone. None of these schemes, however, consider potential biological characteristics of the bone. Here, we employed multiscale analyses to identify and characterize type I and type III bones in murine jaws. We then combined these analytical tools with in vivo models of osteotomy healing and implant osseointegration to determine if one type of bone healed faster and supported osseointegration better than another. Collectively, these studies revealed a strong positive correlation between bone remodeling rates, mitotic activity, and osteotomy site healing in type III bone and high endogenous Wnt signaling. This positive correlation was strengthened by observations showing that the osteoid matrix that is responsible for implant osseointegration originates from Wnt-responsive cells and their progeny. The potential application of this knowledge to clinical practice is discussed, along with a theory unifying the role that biology and mechanics play in implant osseointegration.

NF-κB as a Therapeutic Target in Inflammatory-Associated Bone Diseases.

Inflammation is a defensive mechanism for pathogen clearance and maintaining tissue homeostasis. In the skeletal system, inflammation is closely associated with many bone disorders including fractures, nonunions, periprosthetic osteolysis (bone loss around orthopedic implants), and osteoporosis. Acute inflammation is a critical step for proper bone-healing and bone-remodeling processes. On the other hand, chronic inflammation with excessive proinflammatory cytokines disrupts the balance of skeletal homeostasis involving osteoblastic (bone formation) and osteoclastic (bone resorption) activities. NF-κB is a transcriptional factor that regulates the inflammatory response and bone-remodeling processes in both bone-forming and bone-resorption cells. In vitro and in vivo evidences suggest that NF-κB is an important potential therapeutic target for inflammation-associated bone disorders by modulating inflammation and bone-remodeling process simultaneously. The challenges of NF-κB-targeting therapy in bone disorders include: (1) the complexity of canonical and noncanonical NF-κB pathways; (2) the fundamental roles of NF-κB-mediated signaling for bone regeneration at earlier phases of tissue damage and acute inflammation; and (3) the potential toxic effects on nontargeted cells such as lymphocytes. Recent developments of novel inhibitors with differential approaches to modulate NF-κB activity, and the controlled release (local) or bone-targeting drug delivery (systemic) strategies, have largely increased the translational application of NF-κB therapy in bone disorders. Taken together, temporal modulation of NF-κB pathways with the combination of recent advanced bone-targeting drug delivery techniques is a highly translational strategy to reestablish homeostasis in the skeletal system.

Cryopreservation on a cryo-plate of Arundina graminifolia protocorms, dehydrated with silica gel and drying beads.

BACKGROUND: There are various methods for the cryopreservation of plant material, with each biological specimen potentially requiring protocol optimization to maximize success. OBJECTIVE: The aim of this study is to compare droplet-vitrification, encapsulation-dehydration, and the cryo-plate method for cryopreservation of protocorms of the orchid Arundina graminifolia, using silica gel and drying beads as the desiccation materials. MATERIALS AND METHODS: The cryo-plate method included preculture of protocorms, developed from seeds, placed on aluminium cryo-plates and embedded in alginate gel. Cryo-plates were surface dried using sterile filter paper, placed in Petri dishes containing 50 g silica gel or 30 g drying beads in a laminar air-flow cabinet. Specimens on cryo-plates were dehydrated to 25 % moisture content, placed into 2 mL cryotubes and plunged directly into liquid nitrogen for 1 d. RESULTS: For cryopreservation, the cryo-plate method, involving dehydration with 30 g drying beads gave the highest regrowth (77 %), followed by the encapsulation-dehydration method with 30 g drying beads (64 % regrowth) and the droplet-vitrification method, following exposure to PVS2 solution for 20 min (33 % regrowth). CONCLUSIONS: Regrowth of cryopreserved protocorms using the cryo-plate method was rapid with the highest survival and regrowth.

The obese child in the Intensive Care Unit. Update. / El niño obeso en la Unidad de Cuidados Intensivos. Puesta al día.

Given that childhood obesity is an epidemic, the frequency of critically-ill patients who are overweight or obese seen at intensive care units has increased rapidly. Adipose tissue is an endocrine organ that secretes a number of protein hormones, including leptin, which stands out because it regulates adipose tissue mass. The presence of arterial hypertension, metabolic syndrome, diabetes mellitus, respiratory disease and chronic kidney disease may become apparent and complicate the course of obese pediatric patients in the Intensive Care Unit. Obesity management is complex and should involve patients, their families and the medical community. It should be coordinated with comprehensive government health policies and implemented in conjunction with a change in cultural context.

Actualmente, la obesidad infantil constituye una epidemia. La frecuencia de pacientes críticos con sobrepeso u obesidad ha aumentado rápidamente en las unidades de cuidados intensivos. El tejido adiposo es un órgano endocrino que secreta varias hormonas proteicas, entre las que se destaca la leptina, la cual es reguladora de su masa. La presencia de hipertensión arterial, síndrome metabólico, diabetes mellitus, enfermedades respiratorias y enfermedad renal crónica se puede manifestar en el paciente pediátrico obeso durante su estadía en la Unidad de Cuidados Intensivos y complicar su evolución. El tratamiento de la obesidad es complejo y debe involucrar al paciente, a su familia y a la comunidad médica. Debe realizarse en coordinación con políticas sanitarias gubernamentales integrales y en conjunto con un cambio de marco cultural.

Effect of Ovariohysterectomy at the Time of Tumor Removal in Dogs with Mammary Carcinomas: A Randomized Controlled Trial.

BACKGROUND: Ovarian hormones play crucial roles in mammary carcinogenesis. However, whether ovarian ablation by ovariohysterectomy (OHE) improves the prognosis in dogs with mammary carcinomas is unclear. OBJECTIVES: Determine if OHE at the time of mastectomy improves the prognosis in dogs with mammary carcinomas and evaluate if hormonal factors influence the effect of OHE. ANIMALS: Sixty intact dogs with mammary carcinomas. METHODS: Dogs were randomly assigned in a 1:1 ratio to undergo OHE (n = 31) or not (n = 29) at the time of tumor removal. Peri-surgical serum estradiol (E2) and progesterone concentrations were measured, tumor diagnosis was confirmed histologically, and tumor estrogen and progesterone receptor status was immunohistochemically determined. The dogs were monitored for recurrence and metastases every 3-4 months for at least 2 years. Uni- and multivariable survival analyses were performed with relapse and all-cause death as endpoints in addition to univariable subgroup analyses. RESULTS: Overall, OHE did not significantly decrease hazard of relapse (hazard ratio [HR], 0.64; P = .18) or all-cause death (HR, 0.87; P = .64) in univariable analyses. In multivariable analysis OHE did not significantly influence the hazard of relapse (HR, 0.54; P = .12), but an interaction effect was identified between ER status and E2 (P = .037). Subgroup analysis identified decreased hazard of relapse in the OHE group compared to the non-OHE group in the subsets of dogs with increased E2 (HR, 0.22; P = .012) or grade 2 tumors (HR, 0.26; P = .02). CONCLUSION: Dogs with grade 2, ER-positive tumors, or with increased peri-surgical serum E2 concentration represent a subset of dogs with mammary carcinomas likely to benefit from OHE.

Inhibition of osteolysis and increase of bone formation after local administration of siRNA-targeting RANK in a polyethylene particle-induced osteolysis model.

Receptor activator of nuclear factor kappa-B (RANK) and RANK-ligand are relevant targets for the treatment of polyethylene particle-induced osteolysis. This study assessed the local administration of siRNA, targeting both human RANK and mouse Rank transcripts in a mouse model. Four groups of mice were implanted with polyethylene (PE) particles in the calvaria and treated locally with 2.5, 5 and 10 µg of RANK siRNA or a control siRNA delivered by the cationic liposome DMAPAP/DOPE. The tissues were harvested at day 9 after surgery and evaluated by micro-computed tomography, tartrate-resistant acid phosphatase (TRAP) immunohistochemistry for macrophages and osteoblasts, and gene relative expression of inflammatory and osteolytic markers. 10 µg of RANK siRNA exerted a protective effect against PE particle-induced osteolysis, decreasing the bone loss and the osteoclastogenesis, demonstrated by the significant increase in the bone volume (P<0.001) and by the reduction in both the number of TRAP(+) cells and osteoclast activity (P<0.01). A bone anabolic effect demonstrated by the formation of new trabecular bone was confirmed by the increased immunopositive staining for osteoblast-specific proteins. In addition, 5 and 10 µg of RANK siRNA downregulated the expression of pro-inflammatory cytokines (P<0.01) without depletion of macrophages. Our findings show that RANK siRNA delivered locally by a synthetic vector may be an effective approach for reducing osteolysis and may even stimulate bone formation in aseptic loosening of prosthetic implants.

Osteocalcin, under-carboxylated osteocalcin and osteopontin are not associated with gestational diabetes mellitus but are inversely associated with leptin in non-diabetic women.

OBJECTIVE: To measure serum osteocalcin (OC), under-carboxylated osteocalcin (ucOC), osteopontin (OPN), and leptin in pregnant women with gestational diabetes mellitus (GDM) and in healthy pregnant women during pregnancy and after birth and relate these markers to glucose metabolism. METHODS: This was a prospective study including 60 women with GDM and 60 subjects with normal gestation who were evaluated at gestational week 30 and 6 weeks postpartum. Serum OC, ucOC, OPN, leptin, insulin and insulin resistance were evaluated during the study. RESULTS: Bone biomarkers and leptin were similar between GDM and normal pregnancy. After delivery, OC, ucOC and OPN increased in both groups, while leptin decreased only in healthy controls. Bone markers did not correlate with insulin and insulin resistance in the two groups, but leptin was positively correlated with insulin and insulin resistance and negatively correlated with bone biomarkers only in healthy women. Furthermore, the women who developed diabetes postpartum had lower levels of OC than women with normal glucose tolerance. CONCLUSION: GDM is not associated with OC, ucOC, OPN, and leptin and does not correlate with insulin resistance. At postpartum, women who develop diabetes have lower osteocalcin concentrations. Leptin correlates with insulin resistance and bone biomarkers in non-diabetic women.

Sedation and analgesia in children undergoing invasive procedures.

INTRODUCTION: As a result of the increased number of both diagnostic and therapeutic procedures in pediatric outpatients, sedation and analgesia have gained relevance in this context. OBJECTIVE: To characterize the type of sedation and analgesia used by pediatric sedation teams in procedures done outside the operating room, as well as its safety and outcome. POPULATION AND METHODS: All procedures performed in 1 month to 5 year old patients under intravenous sedation with midazolam, ketamine, propofol or lidocaine were analyzed over a 14-month period. The Ramsay sedation scale and the CHEOPS pain scale were used to determine the response to the sedation and analgesia administered. RESULTS: A total of 186 procedures were analyzed. The results of the evaluation of response to sedation and analgesia indicated that an adequate deep sedation was obtained in 98% of cases, and that an adequate analgesia was achieved in 92% of patients. Around 12% of the procedures were associated with adverse events, all related to the airways, and none was serious. The only statistically significant endpoint associated with adverse events were procedures which involved airway interventions, i.e., fibrobronchoscopy, upper gastrointestinal endoscopy or transesophageal echocardiogram, with an OR of 6.27 (95% CI: 1.28-30.63; p = 0.023). CONCLUSIONS: In this group of patients, intravenous outpatient sedation and analgesia administered by a specialized team were safe and effective.

Sedation and analgesia in children undergoing invasive procedures / Sedación y analgesia para procedimientos invasivos en los niños

Introduction. As a result of the increased number of both diagnostic and therapeutic procedures in pediatric outpatients, sedation and analgesia have gained relevance in this context. Objective. To characterize the type of sedation and analgesia used by pediatric sedation teams in procedures done outside the operating room, as well as its safety and outcome. Population and Methods. All procedures performed in 1 month to 5 year old patients under intravenous sedation with midazolam, ketamine, propofol or lidocaine were analyzed over a 14-month period. The Ramsay sedation scale and the CHEOPS pain scale were used to determine the response to the sedation and analgesia administered. Results. A total of 186 procedures were analyzed. The results of the evaluation of response to sedation and analgesia indicated that an adequate deep sedation was obtained in 98% of cases, and that an adequate analgesia was achieved in 92% of patients. Around 12% of the procedures were associated with adverse events, all related to the airways, and none was serious. The only statistically significant endpoint associated with adverse events were procedures which involved airway interventions, i.e., fibrobronchoscopy, upper gastrointestinal endoscopy or transesophageal echocardiogram, with an OR of 6.27 (95% CI: 1.28-30.63; p = 0.023). Conclusions. In this group of patients, intravenous outpatient sedation and analgesia administered by a specialized team were safe and effective.(AU)

Introducción. Producto del aumento de los procedimientos pediátricos, tanto diagnósticos como terapéuticos fuera del quirófano, la sedación y analgesia en este contexto ha cobrado importancia. Objetivo. Caracterizar el tipo de sedoanalgesia utilizada por un equipo de sedación pediátrico en procedimientos fuera del quirófano, así como sus resultados y su seguridad. Pacientes y métodos. Se analizaron todos los procedimientos realizados bajo sedación intravenosa con midazolam, ketamina, propofol o lidocaína, en pacientes de entre 1 mes y 5 años, en un período de 14 meses. Para determinar la respuesta a la sedoanalgesia administrada, se aplicó la escala de sedación de Ramsay y la escala de dolor de CHEOPS. Resultados. Se analizaron 186 procedimientos. Al evaluar la respuesta a la sedoanalgesia, se obtuvo una sedación profunda adecuada en un 98% de los casos y una analgesia adecuada en un 92% de los pacientes. Un 12% de los procedimientos se asociaron a efectos adversos, todos relacionados con la vía aérea, ninguno grave. La única variable vinculada de forma estadísticamente significativa a la ocurrencia de eventos adversos fue el procedimiento con intervención de la vía aérea, es decir, fibrobroncoscopia, endoscopia digestiva alta o ecocardiograma transesofágico, con un OR de 6,27 (IC 95% 1,28 a 30,63; p= 0,023). Conclusiones. En este grupo de pacientes la sedación y analgesia intravenosa para procedimientos fuera del quirófano, otorgada por un equipo especializado, resultó segura y eficaz.(AU)

Sedation and analgesia in children undergoing invasive procedures / Sedación y analgesia para procedimientos invasivos en los niños

Introduction. As a result of the increased number of both diagnostic and therapeutic procedures in pediatric outpatients, sedation and analgesia have gained relevance in this context. Objective. To characterize the type of sedation and analgesia used by pediatric sedation teams in procedures done outside the operating room, as well as its safety and outcome. Population and Methods. All procedures performed in 1 month to 5 year old patients under intravenous sedation with midazolam, ketamine, propofol or lidocaine were analyzed over a 14-month period. The Ramsay sedation scale and the CHEOPS pain scale were used to determine the response to the sedation and analgesia administered. Results. A total of 186 procedures were analyzed. The results of the evaluation of response to sedation and analgesia indicated that an adequate deep sedation was obtained in 98% of cases, and that an adequate analgesia was achieved in 92% of patients. Around 12% of the procedures were associated with adverse events, all related to the airways, and none was serious. The only statistically significant endpoint associated with adverse events were procedures which involved airway interventions, i.e., fibrobronchoscopy, upper gastrointestinal endoscopy or transesophageal echocardiogram, with an OR of 6.27 (95% CI: 1.28-30.63; p = 0.023). Conclusions. In this group of patients, intravenous outpatient sedation and analgesia administered by a specialized team were safe and effective.

Introducción. Producto del aumento de los procedimientos pediátricos, tanto diagnósticos como terapéuticos fuera del quirófano, la sedación y analgesia en este contexto ha cobrado importancia. Objetivo. Caracterizar el tipo de sedoanalgesia utilizada por un equipo de sedación pediátrico en procedimientos fuera del quirófano, así como sus resultados y su seguridad. Pacientes y métodos. Se analizaron todos los procedimientos realizados bajo sedación intravenosa con midazolam, ketamina, propofol o lidocaína, en pacientes de entre 1 mes y 5 años, en un período de 14 meses. Para determinar la respuesta a la sedoanalgesia administrada, se aplicó la escala de sedación de Ramsay y la escala de dolor de CHEOPS. Resultados. Se analizaron 186 procedimientos. Al evaluar la respuesta a la sedoanalgesia, se obtuvo una sedación profunda adecuada en un 98% de los casos y una analgesia adecuada en un 92% de los pacientes. Un 12% de los procedimientos se asociaron a efectos adversos, todos relacionados con la vía aérea, ninguno grave. La única variable vinculada de forma estadísticamente significativa a la ocurrencia de eventos adversos fue el procedimiento con intervención de la vía aérea, es decir, fibrobroncoscopia, endoscopia digestiva alta o ecocardiograma transesofágico, con un OR de 6,27 (IC 95% 1,28 a 30,63; p= 0,023). Conclusiones. En este grupo de pacientes la sedación y analgesia intravenosa para procedimientos fuera del quirófano, otorgada por un equipo especializado, resultó segura y eficaz.

Sedation and analgesia in children undergoing invasive procedures. / Sedation and analgesia in children undergoing invasive procedures.

INTRODUCTION: As a result of the increased number of both diagnostic and therapeutic procedures in pediatric outpatients, sedation and analgesia have gained relevance in this context. OBJECTIVE: To characterize the type of sedation and analgesia used by pediatric sedation teams in procedures done outside the operating room, as well as its safety and outcome. POPULATION AND METHODS: All procedures performed in 1 month to 5 year old patients under intravenous sedation with midazolam, ketamine, propofol or lidocaine were analyzed over a 14-month period. The Ramsay sedation scale and the CHEOPS pain scale were used to determine the response to the sedation and analgesia administered. RESULTS: A total of 186 procedures were analyzed. The results of the evaluation of response to sedation and analgesia indicated that an adequate deep sedation was obtained in 98

of cases, and that an adequate analgesia was achieved in 92

of patients. Around 12

of the procedures were associated with adverse events, all related to the airways, and none was serious. The only statistically significant endpoint associated with adverse events were procedures which involved airway interventions, i.e., fibrobronchoscopy, upper gastrointestinal endoscopy or transesophageal echocardiogram, with an OR of 6.27 (95

CI: 1.28-30.63; p = 0.023). CONCLUSIONS: In this group of patients, intravenous outpatient sedation and analgesia administered by a specialized team were safe and effective.

Encondromatosis múltiple [Sindrome de Ollier] / Multiple enchondromatosis

Enchondromatosis or Ollier syndrome is defined by the presence of multiple enchondromas with an asymmetrical distribution of low prevalence. Enchondromas are common intra osseous benign cartilage tumors cartilaginous which develop to close proximity growth plate cartilage. Cartilage injuries can be very variable in terms of size, number, location, evolution of enchondroma, age of onset and of diagnosis, requirement for surgery. Clinical problems caused by enchondromas include skeletal malformations, an asymetrics hortening of extremity with limping, and potential risk of malignant change to chondrosarcoma. The condition in which multiple enchondromatosis is associated to soft tissue hemangiomas is known as Maffucci syndrome. So far, both Ollier disease and Maffucci syndrome have occurred only in isolated cases. It has not been established if the disease depends on a single gene or combination of several mutations. The diagnosis is based on clinical and radiological conventional analysis. Histological analysis has a limited role and is used if malignancy is suspected. There is no medical treatment for enchondromatosis. Surgical treatment is recommended only in case of complications. Though, it is difficult to establish a prognosis for Ollier disease, it is found that the early onset forms are usually more severe.

Epimastigogénesis de Trypanosoma cruzi: método para estudiar in vivo la transformación de tripomastigota en epimastigota / Trypanosoma cruzi epimastigogenesis: a method for studying Trypomastigote to epimastigote transformation in vivo

La epimastigogénesis de Trypanosoma cruzi ocurre naturalmente en el intestino del hospedador invertebrado. Se desconoce si los cambios morfológicos que ocurren durante la transformación de los tripomastigotas sanguíneos en epimastigotas son idénticos para diferentes aislados de T. cruzi. Aquí mostramos un método útil para estudiar los eventos que ocurren durante la epimastigogénesis, comparando parásitos de diferentes procedencias epidemiológicas. Se alimentaron artificialmente ninfas de V estadio de Rhodnius prolixus con una solución ad hoc conteniendo tripomastigotas tipo-sanguíneo y siguiendo los cambios morfológicos por 8 días. Los contenidos del intestino anterior de las ninfas se obtuvieron decapitando y comprimiendo el abdomen lo que permitió obtener rápidamente casi 100% del inóculo con cargas entre 1,9 y 8,9 × 106 tripomastigotas/ninfa. El número de parásitos por ninfa y los cambios morfológicos se determinaron por Microscopia de Contraste de Fases y coloración con Giemsa. Las ninfas ingirieron 7,4 veces su peso de solución infectante, con volúmenes entre 101 y 357 µL (229 ± 66 mg), 50% de esa ingesta se eliminó como orina durante las primeras 24 h. Los tripomastigotas se transformaron en formas redondeadas antes de evolucionar a epimastigotas, siguiendo cinéticas diferentes según el aislado. Proponemos esta metodología para estudiar rápida y cuantitativamente los eventos tempranos de la epimastigogénesis de T. cruzi in vivo.

Trypanosoma cruzi epimastigogenesis naturally occurs in the intestine of the invertebrate host. It is not known whether the morphological changes that occur during transformation of bloodstream trypomastigotes to epimastigotes are identical for different T. cruzi isolates. This research shows a useful method for studying the events that occur during epimastigogenesis, comparing parasites from epidemiological sources. Rhodnius prolixus V stage nymphs were fed artificially with an ad hoc solution containing blood-like trypomastigotes and the morphological changes were examined during eight days. Anterior intestinal contents were removed by decapitation and squeezing the abdomen of the nymphs, which permitted obtaining quickly almost 100% of the inoculate with loads between 1.9 and 8.9 × 106 trypomastigotes/nymph. The number of parasites per nymph and morphological changes were determined using phase microscopy with Giemsa staining. The nymphs ingested 7.4 times their weight of the infecting solution with volumes between 101 e 357 µL (229 ± 66 mg); 50% of the ingest was eliminated as urine during the first 24 hours. The trypomastigotes transformed to rounded forms before evolving into epimastigotes following different kinetics according to the isolate. This method is proposed for rapid, quantitative study of the early events of epimastigogenesis for T. cruzi in vivo.

Reemplazo renal en el post-operatorio de niños sometidos a cirugía cardíaca con circulación extracorpórea / Renal replacement therapy after cardiac surgery with extracorporeal circulation

Objective: Acute kidney injury (AKI) is a frequent complication of cardiac surgery with cardiopulmonary bypass (CPB). The aim of this study was to determine the incidence of renal replacement therapy (RRT) requirement in children undergoing surgical repair for congenital cardiopathies and identify the risk factors for requiring RRT. Patients and Methods: A retrospective, descriptive study was performed. The records of patients under 18 years undergoing cardiac surgery with CPB (January 2001 to July 2008) who required RRT (n = 15) and from a random patients sample that did not require it (n = 57) were analysed. Results: Fifteen children out of 942 required acute RRT (1.6 percent). Initial RRT was peritoneal dialysis (PD) in all of them. The main indications were hypervolemia and/or oligoanuria. Ten patients experienced complications associated to therapy and 14 patients had a history of serious intraoperative events. In multivariated analysis, hypotension (OR 36.0, CI 95 percent: 5.5-235.6) and serious low cardiac output (LCO) (OR 14.1, CI 95 percent: 1.47-135.32) were significant risk factors for RRT requirement. In turn, the presence of intraoperative events was significantly associated with the occurrence of hypotension (OR 28.9, CI 95 percent: 3.6-233.9) and LCO (OR 5.3, CI 95 percent: 1.126.6) during the post-surgical evolution. Conclusion: In this experience, severe hypotension and low cardiac output were significant risk factors for RRT requirement. The incidence of RRT was 1.6 percent. Renal function should be closely evaluated in those patients with surgical events. RRT should be early considered in those patients with risk factors for renal failure.

Introducción: La insuficiencia renal aguda es una complicación frecuente de la cirugía cardíaca con circulación extracorpórea (CEC). Objetivo: Determinar la incidencia de requerimiento de terapia de reemplazo renal (TRR) en niños sometidos a reparación quirúrgica de cardiopatías congénitas, caracterizarlos e identificar factores de riesgo de requerir TRR. Pacientes y Método: Se realizó un estudio retrospectivo descriptivo con un componente analítico. Se revisaron las fichas clínicas de los pacientes menores de 18 años sometidos a cirugía cardíaca con CEC (enero 2001 a julio 2008) que requirieron TRR (n = 15) y de una muestra aleatoria de pacientes que no la requirieron (n = 57). Resultados: De los 942 niños operados, 15 requirieron TRR aguda (1,6 por ciento). En todos, la TRR inicial fue peritoneodiálisis (PD). Las principales indicaciones fueron hipervolemia y/o oligoanuria. Diez pacientes presentaron complicaciones asociadas a la terapia y 14 tenían antecedentes de incidentes intraoperatorios graves. En forma multivariada, la hipotensión arterial (OR 36,0 IC 95 por ciento: 5,5-235,6) y el hipodébito grave (OR 14,1 IC 95 por ciento: 1,47-135,32) fueron factores de riesgo significativos de requerir TRR. A su vez, la presencia de incidentes intraoperatorios se asoció significativamente al desarrollo de hipotensión (OR 28,9 IC 95 por ciento: 3,6-233,9) e hipodébito (OR 5,3 IC 95 por ciento: 1,1-26,6) durante la evolución post-quirúrgica.

Ventilación no invasiva en insuficiencia respiratoria aguda / Non-invasive ventilation in acute respiratory failure

Background: Non-invasive ventilation (NIV) has become a therapeutic tool for acute respiratory failure in pediatric patients. Objective: To describe NIV experience at a Pediatric Intensive Care Unit, identifying factors associated to modality failure. Methods: Patients cohort who received NIV in acute respiratory failure during 2005-2007. Recolection of clinical and gasometrical variables previous and subsequent to connection to NIV. Descriptive statistic and logistic regression analysis were performed. Results: 51 events of NIV, where 55 percent) cases were congenital cardiopathies. NIV main indication was respiratory distress post-extubation (31.4 percent). 15 patients (29.4 percent) required CMV. In univariate logistic regression for variables, an independent association was found between Fi02 pre-connection and Fi02 subsequent to NIV connection, with necessity of CMV. 9 percent> presented complications and mortality was not related to ventilatory modality. Conclusions: NIV is useful in pediatric patients with acute respiratory insufficiency, with low risk of complications. The variables associated with failure are easy to obtain and interpretate.

Introducción: La ventilación no invasiva (VNI) se ha convertido en una herramienta terapéutica en insuficiencia respiratoria aguda en pediatría. Objetivo: Describir la experiencia con VNI en una unidad de paciente crítico pediátrico, e identificar factores asociados con fracaso de la modalidad. Pacientes y Método: Cohorte de pacientes que recibieron VNI en contexto de insuficiencia respiratoria aguda durante el período 2005-2007. Registro de variables clínicas y gasométricas previo y posterior a la conexión a VNI. Se realizó estadística descriptiva y análisis de regresión logística. Resultados: Analizamos 51 eventos de VNI, 55 por ciento en postoperatorio de cardiopatías congénitas. La principal indicación de VNI fue dificultad respiratoria post extubación (31,4 por ciento). Quince pacientes (29,4 por ciento) fracasaron, requiriendo VMC. Al realizar regresión logística univariada se encontró asociación independiente entre la Fi0(2) pre conexión y Fi0(2) posterior a la conexión a VNI, con la necesidad de VMC. Nueve por ciento presentaron complicaciones. No se observó mortalidad asociada a la modalidad ventilatoria. Conclusiones: La VNI es útil en pacientes pediátricos insuficiencia respiratoria aguda y tiene un bajo riesgo de complicaciones. Las variables asociadas con fracaso de VNI son de fácil obtención e interpretación.

Allergen-sensitization increases mast-cell expression of the exocytotic proteins SNAP-23 and syntaxin 4, which are involved in histamine secretion.

BACKGROUND: Activation of mast cells (MCs) via aggregation of immunoglobulin E (IgE) bound to its high affinity receptor (FcepsilonRI) results in release of inflammatory mediators from secretory granules. Histamine is one of the critical biological mediators released in the allergic response. Synaptosomal-associated protein of 23 kDa (SNAP-23) and syntaxin 4 are plasma membrane proteins that have been associated with exocytosis in MCs. Studies with monoclonal IgEs indicate that binding of IgE to FcepsilonRI induces molecular and biological changes in OBJECTIVES: The aim of this study was to investigate changes in the expression of SNAP-23 and syntaxin 4 by MCs following rat sensitization with ovalbumin (OVA). In addition, we assessed whether these proteins were involved in histamine secretion. METHODS: SNAP-23 and syntaxin 4 expression was analyzed by Western blot using MCs from control and sensitized animals. Successful sensitization was confirmed based on the passive cutaneous anaphylaxis reaction. To test the role of these exocytotic proteins in histamine secretion, permeabilized MCs were incubated with SNAP-23 and syntaxin 4 antibodies. RESULTS: Expression of SNAP-23 and syntaxin 4 was significantly higher in MCs from OVA-sensitized rats than in cells from control animals. In addition, incubation of permabilized cells with antibodies to SNAP-23 and syntaxin 4 led to a marked reduction of histamine secretion in stimulated cells. CONCLUSIONS: Sensitization with OVA increases the expression of SNAP-23 and syntaxin 4 in MCs. Furthermore, our data suggest that these exocytotic proteins participate in histamine secretion.

Botulismo infantil: comunicación de un caso y revisión del tema / Infant botulism: case-report and literature review

Background: Infant botulism is a rare and potentially lethal neurological disease produced by the ingestion of a neurotoxin secreted by Clostridium botulinum, causing diffuse paralysis. Objective: Describe the first case in Chile since the establishment of an obligatory report and describe the diagnosis, clinical presentation and outcome. Case-report: A 2 months-old male with 48 hours of poor feeding and swallowing, weak cry, listlessness and constipation. He was admitted for hospitalization with probable sepsis and required tracheotomy due to apnea with failed endotracheal intubation, requiring mechanical ventilation for 150 days and hospitalization during 180 days. The diagnosis was confirmed by isolating Clostridium botulinum toxin from stool. Conclusion: The diagnosis of infant botulism requires a high suspicion index and the treatment includes intensive care monitorization with general support.

El botulismo infantil es una enfermedad infrecuente que ha sido confirmada sólo en menores de un año, se produce por ingestión de esporas de clostridium botulinum que producen una neurotoxina in vivo, la cual se absorbe y es responsable de la parálisis flácida descendente aguda característica de esta enfermedad. Objetivo: Presentación del primer caso descrito desde que la notificación es obligatoria en Chile y revisión del tema. Caso clínico: Lactante de 2 meses. Dos días previo al ingreso presenta succión débil, hiporeactividad y llanto disfónico, consultando en Servicio de Urgencia y decidiéndose su hospitalización. Estudio: hemograma, PCR, neuroimagenes, EEG LCR, EMG normales y toxicológico negativo. Se confirma Clostridium botulinum productor de la toxina botulínica tipo A. Requirió ventilación mecánica a través de traqueotomía por 150 días y es dado de alta a los 180 días. Conclusión: El diagnóstico requiere de un alto índice de sospecha, el tratamiento es de soporte evitando las complicaciones.

Proyecto ANACO-UCV: Estudio epidemiológico sobre la pérdida prematura del primer molar permanente en niños con edades comprendidas entre 6 y 10 años

El convenio U.C.V.-Corpoamigos ANACO es uno de los seminarios del Programa de Extensión Docencia-Servicio de la Facultad de Odontología que se viene realizando en 16 estados del país. Dicho seminario cuenta con los recursos humanos, materiales y financieros necesarios para una óptima atención a la comunidad, por lo cual es considerado uno de los seminarios más importantes de la facultad de odontología de la UCV. En el siguiente estudio de investigación se tomaron 142 pacientes de ambos sexos con edades comprendidas entre 6 y 10 años (con la pérdida de algunos primeros molares). Los resultados obtenidos muestran una alta prevalencia de pérdida de este molar, lo que nos lleva a enfrentar la problemática presente en las poblaciones rurales por la pérdida del primer molar a edad temprana, cuya situación se agrava por falta de programas preventivos en dichas regiones. Es importante hacer notar la existencia de investigaciones epidemiológicas de este tema en poblaciones rurales como la de Anaco (AU)