Equivalence of variance components between standard and recursive genetic models using LDL' transformations.

BACKGROUND: Recursive models are a category of structural equation models that propose a causal relationship between traits. These models are more parameterized than multiple trait models, and they require imposing restrictions on the parameter space to ensure statistical identification. Nevertheless, in certain situations, the likelihood of recursive models and multiple trait models are equivalent. Consequently, the estimates of variance components derived from the multiple trait mixed model can be converted into estimates under several recursive models through LDL' or block-LDL' transformations. RESULTS: The procedure was employed on a dataset comprising five traits (birth weight-BW, weight at 90 days-W90, weight at 210 days-W210, cold carcass weight-CCW and conformation-CON) from the Pirenaica beef cattle breed. These phenotypic records were unequally distributed among 149,029 individuals and had a high percentage of missing data. The pedigree used consisted of 343,753 individuals. A Bayesian approach involving a multiple-trait mixed model was applied using a Gibbs sampler. The variance components obtained at each iteration of the Gibbs sampler were subsequently used to estimate the variance components within three distinct recursive models. CONCLUSIONS: The LDL' or block-LDL' transformations applied to the variance component estimates achieved from a multiple trait mixed model enabled inference across multiple sets of recursive models, with the sole prerequisite of being likelihood equivalent. Furthermore, the aforementioned transformations simplify the handling of missing data when conducting inference within the realm of recursive models.

Immediate Results of the Use of Split-Thickness Skin Autografts With and Without Acellular Dermal Matrix in Patients with Burns: A Comparative Study in a Colombian Population.

Dermal substitutes have become fundamental tools for covering skin defects, most recently with biological subtypes such as glycerolized acellular dermal matrix (GADM). However, literature regarding this matter is scarce in Latin America and Colombia. In this descriptive observational study, we compared the use of partial skin autografts (PSA) combined with GADM and autografts without GADM. Patients were selected from the burn unit of a hospital in northeastern Colombia between 2021 and 2022. Two study groups were defined: one receiving GADM plus PSA and the other control receiving only a partial split-thickness autograft. A total of 29 patients with 68 body areas were included, with an average age of 20 years. Most cases involved third-degree burns caused by flame. Hospitalization time was the same for both groups (41 days). The percentage of grafts taken was similar in both groups; in the GADM with autografts group, it was 94.7% compared with 96% in the control group. The presence of complications was similar in both groups. GADM produced in local tissue banks is a cost-effective alternative. It can be used in a single surgical procedure without increasing complications, providing a postsurgical course similar to autografts alone. Granting the potential long-term benefits that dermal matrices give for healing in these patients, which should be evaluated in subsequent studies.

Genomic Scanning of Inbreeding Depression for Litter Size in Two Varieties of Iberian Pigs.

Inbreeding depression is expected to be more pronounced in fitness-related traits, such as pig litter size. Recent studies have suggested that the genetic determinism of inbreeding depression may be heterogeneous across the genome. Therefore, the objective of this study was to conduct a genomic scan of the whole pig autosomal genome to detect the genomic regions that control inbreeding depression for litter size in two varieties of Iberian pigs (Entrepelado and Retinto). The datasets consisted of 2069 (338 sows) and 2028 (327 sows) records of litter size (Total Number Born and Number Born Alive) for the Entrepelado and Retinto varieties. All sows were genotyped using the Geneseek GGP PorcineHD 70 K chip. We employed the Unfavorable Haplotype Finder software to extract runs of homozygosity (ROHs) and conducted a mixed-model analysis to identify highly significant differences between homozygous and heterozygous sows for each specific ROH. A total of eight genomic regions located on SSC2, SSC5, SSC7, SSC8, and SSC13 were significantly associated with inbreeding depression, housing some relevant genes such as FSHR, LHCGR, CORIN, AQP6, and CEP120.

Satisfacción estética y funcional tras reducción cerrada de fracturas nasales: implementación de la escala NOSE / Aesthetic and functional satisfaction after closed reduction of nasal fractures: implementation of the NOSE scale

Introducción y objetivo: La fractura nasal es la lesión facial más común y más del 50 % de todas las fracturas faciales en adultos. Debido a que en muchas ocasiones no es diagnosticada y tratada oportunamente, puede generar diferentes grados de limitación funcional y resultados estéticos indeseables. Pocos estudios evalúan la satisfacción de los pacientes tratados con técnica cerrada de reducción de fractura nasal. Nuestro objetivo es valorar la satisfacción funcional y estética posterior a reducción cerrada de fractura de huesos nasales en un hospital de Colombia, mediante la escala de evaluación de síntomas de obstrucción nasal (NOSE, por sus siglas en inglés - nasal obstruction symptom evaluation) y la escala estética subjetiva. Material y método: Estudio observacional analítico prospectivo de pacientes con fractura nasal llevados a reducción cerrada en el Hospital Universitario de Santander, Colombia. Se registraron las puntuaciones de las escalas NOSE y estética subjetiva, antes y 2 meses después de la cirugía. Resultados: Evaluamos 55 pacientes, 90.9% hombres. La mediana de edad fue de 31 años (RIC 24-48). El contexto de lesión principal fue violencia física (40%), seguido de accidente de tránsito (32.7%). Tras el procedimiento, los pacientes presentaron mejoría de obstrucción nasal medida con la escala NOSE (p<0.001); antes de la cirugía el 89% presentaba obstrucción nasal moderada-severa, posteriormente descendió a 14.5%. La escala NOSE mostró fabilidad por consistencia interna con alfa de Cronbach de 0.8317. Tras la cirugía hubo aumento de la satisfacción respecto al aspecto nasal (p<0.001). Conclusiones: En nuestro estudio, el cuestionario NOSE permitió cuantificar la mejora de síntomas de obstrucción nasal en pacientes con reducción cerrada por fractura de huesos nasales. Observamos mejoría de síntomas obstructivos nasales y aumento de satisfacción estética.Nivel de evidencia científica 4c Terapéutico.(AU)

Background and objective: Nasal fracture is the most common facial injury, accounting for more than 50% of all facial fractures in adults. Because it is often not diagnosed and treated promptly, it can generate different degrees of functional limitation and undesirable aesthetic results. Few studies evaluate the satisfaction of patients treated with the closed nasal fracture reduction technique. Our objective is to evaluate functional and aesthetic satisfaction after closed reduction of a nasal bone fracture in a hospital in Colombia, using the nasal obstruction symptom evaluation (NOSE) and subjective aesthetic scales. Methods: Prospective analytical observational study of patients with nasal fractures undergoing closed reduction at the University Hospital of Santander, Colombia. The scores of the NOSE scales and subjective aesthetics were recorded, before and 2 months after surgery. Results: We evaluated 55 patients, 90.9% men. Median age 31 years (IQR 24-48). The main injury context was physical violence (40%), followed by traffic accident (32.7%). After the procedure, the patients presented improvement in nasal obstruction measured with the NOSE scale (p<0.001); before surgery, 89% had moderate-severe nasal obstruction, later it decreased to 14.5%. The NOSE scale showed reliability due to internal consistency with Cronbach's alpha of 0.8317. After surgery, there was an increase in satisfaction regarding the nasal appearance (p<0.001). Conclusions: The NOSE questionnaire allows us to quantify the improvement of nasal obstruction symptoms in patients with closed reduction due to nasal bone fracture. Improvement of nasal obstructive symptoms and increased aesthetic satisfaction was observed.Level of evidence 4c Terapeutic.(AU)

Burns in the context of a shared psychotic disorder in a Colombian referral centre: A case report.

INTRODUCTION: Shared paranoid disorder is characterised by the development of psychotic symptoms in people who have a close affective bond with a subject suffering from a mental disorder. This case is the first case of burn injuries reported in the context of this disorder. CASE: We describe a young couple, with a similar pattern of burns caused by contact with a griddle. The injuries are the result of the aggression caused by a relative of one of them, who presented psychotic symptoms, related to the previously undiagnosed spectrum of schizophrenia. CONCLUSIONS: The impact of this condition encompasses social, physical and psychological components, requiring multidisciplinary management and a high index of diagnostic suspicion.

Quemaduras en el contexto de un trastorno psicótico compartido en un centro de referencia colombiano: reporte de caso

Introducción: El trastorno psicótico compartido se caracteriza por la aparición de síntomas psicóticos en personas que tienen un vínculo afectivo estrecho con un sujeto que padece un trastorno mental; este caso es el primer reporte de lesiones por quemaduras en el contexto de este trastorno. Caso: Se trata de una pareja joven, con un patrón similar de quemaduras causadas por el contacto con una plancha. Las lesiones son el resultado de la agresión causada por un familiar de uno de ellos, que presentaba síntomas psicóticos relacionados con el espectro de esquizofrenia no diagnosticado previamente. Conclusiones: El impacto de esta afección abarca los componentes social, físico y psicológico y requiere un tratamiento multidisciplinario y un alto índice de sospecha diagnóstica.

Introduction: Shared paranoid disorder is characterised by the development of psychotic symptoms in people who have a close affective bond with a subject suffering from a mental disorder. This case is the first case of burn injuries reported in the context of this disorder. Case: We describe a young couple, with a similar pattern of burns caused by contact with Paranoid disorders a griddle. The injuries are the result of the aggression caused by a relative of one of them, who presented psychotic symptoms, related to the previously undiagnosed spectrum of schizophrenia. Conclusions: The impact of this condition encompasses social, physical and psychological components, requiring multidisciplinary management and a high index of diagnostic suspicion.

Caracterización de pacientes operados de craneosinostosis no sindrómica. Villa Clara, 2018-2022

Fundamento la craneosinostosis es una de las patologías neuroquirúrgicas más frecuentes en la edad pediátrica. Los conocimientos sobre su manejo son de vital importancia para intervenir con el tratamiento de manera oportuna. Objetivo caracterizar los pacientes operados de craneosinostosis no sindrómica. Métodos se realizó un estudio descriptivo y de corte transversal, en el período enero/2018- diciembre/2022, con la totalidad de pacientes intervenidos de craneosinostosis en el Hospital Pediátrico José Luis Miranda, de Villa Clara (N=28). Las variables analizadas fueron: sexo, color de la piel, clasificación de la malformación según sutura afectada, síntomas y signos asociados a la malformación, edad al realizar la intervención quirúrgica, técnica quirúrgica y complicaciones. Resultados se observó predominio del sexo masculino y de pacientes con color blanco de la piel. La forma de presentación más frecuente fue la escafocefalia, y se asoció a síntomas como el retardo en el desarrollo psicomotor y estrabismo. Las técnicas quirúrgicas realizadas fueron de remodelado total de la bóveda craneal, que en la mayoría de los niños se realizó antes de los 23 meses. La complicación más frecuente fue la infección de la herida quirúrgica. Conclusiones la craneosinostosis es una patología neuroquirúrgica frecuente en el sexo masculino. La forma de presentación más frecuente es la escafocefalia y se puede asociar a síntomas y signos neurológicos. Las técnicas quirúrgicas realizadas para remodelado de la bóveda craneal se deben realizar antes del primer año de vida, con vistas a disminuir el índice de complicaciones.

Background craniosynostosis is one of the most frequent neurosurgical pathologies in the pediatric age. Knowledge about its management is of vital importance to intervene with treatment in a timely manner. Objective to characterize the patients operated on for non-syndromic craniosynostosis. Methods a descriptive and cross-sectional study was carried out, from January/2018 to December/2022, with all the patients operated on for craniosynostosis at the José Luis Miranda Pediatric Hospital, in Villa Clara (N=28). The analyzed variables were: sex, skin color, classification of the malformation according to the affected suture, symptoms and signs associated with the malformation, age at surgery, surgical technique, and complications. Results a predominance of the male sex and patients with white skin color was observed. The most frequent form of presentation was scaphocephaly, and it was associated with symptoms such as delayed psychomotor development and strabismus. The surgical techniques performed were total remodeling of the cranial vault, which in most children was performed before 23 months old. The most frequent complication was infection of the surgical wound. Conclusions craniosynostosis is a frequent neurosurgical pathology in the male sex. The most frequent form of presentation is scaphocephaly and it can be associated with neurological symptoms and signs. Surgical techniques performed for remodeling of the cranial vault must be performed before the first year of life, in order to reduce the complications rate.

An exhaustive evaluation of modeling ecological niches above species level to predict marine biological invasions.

Identifying the areas of the world with suitable environmental conditions for the establishment of invasive species represents a fundamental basis for preventing their impacts. One of the most widely used tools for this is ecological niche modeling. Nonetheless, this approach may underestimate the specie's physiological tolerances (it's potential niche) since wildlife populations of species usually do not occupy their entire environmental tolerance. Recently, it has been suggested that incorporating occurrences of phylogenetically related species improves the prediction of biological invasions. However, the reproducibility of this technique remains unclear. Here, we evaluated the generality of this protocol by assessing whether the construction of modeling units above species level improves the capacity of niche models to predict the distribution of 26 target marine invasive species. For each, we constructed supraspecific modeling units based on published phylogenies by grouping the native occurrence records of each invasive species with the records of its phylogenetically closest relative. We also considered units at species level, including only the presence of records in the native areas of the target species. We generated ecological niche models for each unit with three modeling methods (minimum volume ellipsoids - MVE, machine learning algorithms - Maxent and a presence-absence method - GLM). In addition, we grouped the 26 target species based on whether or not the species are in environmental pseudo-equilibrium (i.e., it occupies all habitats where it can disperse) and have any geographical or biological constraints. Our results suggest that the construction of supraspecific units improves the predictive capacity of correlative models to estimate the invasion area of our target species. This modeling approach consistently generated models with a higher predictive ability for species in non-environmental pseudo-equilibrium and with geographical constraints.

Sources, pathways and concentrations of potentially toxic trace metals in home environments.

Despite ongoing concerns about trace metal and metalloid (trace metals) exposure risks from indoor dust, there has been limited research examining their sources and relationship to outdoor soils. Here we determine the concentrations and sources for potentially toxic trace metals arsenic (As), chromium (Cr), copper (Cu), manganese (Mn), lead (Pb) and zinc (Zn) and their pathways into homes in Sydney, Australia, using home-matched indoor dust (n = 166), garden soil (n = 166), and road dust samples (n = 51). All trace metals were more elevated indoors versus their matched garden soil counterparts. Indoor Cu and Zn dust concentrations were significantly more enriched than outdoor dusts and soils, indicating indoor sources were more relevant for these elements. By contrast, even though Pb was elevated in indoor dust, garden soil concentrations were correspondingly high, indicating that it remains an important source and pathway for indoor contamination. Elevated concentrations of As, Pb and Zn in garden soil and indoor dust were associated with home age (>50 years), construction materials, recent renovations and deteriorating interior paint. Significant correlations (p < 0.05) between road dust and garden soil Cu concentrations, and those of As and Zn in soil and indoor dust, and Pb across all three media suggest common sources. Scanning electron microscopy (SEM) analysis of indoor dust samples (n = 6) showed that 57% of particles were derived from outdoor sources. Lead isotopic compositions of soil (n = 21) and indoor dust (n = 21) were moderately correlated, confirming the relevance of outdoor contaminants to indoor environments. This study illustrates the source, relationship and fate of trace metals between outdoor and indoor environments. The findings provide insight into understanding and responding to potentially toxic trace metal exposures in the home environment.

Hipotermia episódica postraumática

Introducción: La regulación de temperatura es uno de los mecanismos de control vital de mayor importancia en el ser humano. Entre las causas de hipotermia se describe varias de origen neurológico y no neurológicas. En la mayoría de los casos de hipotermia que se desarrolla secundaria a trauma craneal, se trata de pacientes con daño neurológico severo mantenido pero se encuentran escasas descripciones relacionadas con trauma craneoencefálico leve o en pacientes sin otras secuelas importantes. Objetivo: Examinar un caso de hipotermia episódica postraumática sin afectaciones neurológicas asociadas y sin lesiones orgánicas demostradas. Presentación del caso: Paciente masculino, 14 años, antecedentes de salud. Sufre trauma de cráneo sin repercusión clínica aparente en ese momento. Una semana posterior al trauma comienza a presentar episodios de hipotermia nocturna de duración variable, autolimitados, siempre durante el sueño del paciente. Entre los episodios el paciente se mantiene asintomático. Examen físico normal. Estudios de neuroimagen sin alteración. Se indica reposo y tratamiento médico, primero con carbamazepina y luego con valproato de sodio. Actualmente el paciente muestra mejoría del cuadro, aunque no remisión completa de los episodios. Conclusiones: La hipotermia se relaciona con un elevado número de afecciones. La mayoría de los pacientes con trauma de cráneo que presentan hipotermia tienen asociados otros daños y presentan la afección de forma mantenida. Existen otros pacientes, como el caso presentado, sin lesiones orgánicas demostrables en estudios de imágenes que exteriorizan los trastornos de la termorregulación de forma recurrente con periodos de normalidad entre ellos.

Introduction: Temperature regulation corresponds to one of the most important vital control mechanisms in humans. Among the causes of hypothermia are described several of neurological and non-neurological origin. In most cases of hypothermia that develops secondary to cranial trauma described in literature, these are patients with sustained severe neurological damage but there are few descriptions related to mild cranioencephalic trauma or in patients without other important sequelae. Objective: To examine a case of post-traumatic episodic hypothermia without associated neurological affectations and without demonstrated organic lesions. Case presentation: Male patient, 14 years old, health history. He suffered from a cranial trauma with no apparent clinical repercussion at the time. A week after the trauma, episodes of nocturnal hypothermia of variable duration, self-limiting, always during the patient's sleep, begin to occur. Between episodes the patient remains asymptomatic. Normal physical exam. Neuroimaging studies without alteration. Rest and medical treatment are indicated first with carbamazepine and then with sodium valproate. Currently, the patient shows improvements but not complete remission of the episodes. Conclusions: Hypothermia is associated with a high number of conditions. Most patients with cranial trauma who present hypothermia have other associated damages and present hypothermia in a frequent manner, but there are other patients, such as the case presented, without comprobable organic lesions in imaging studies that present thermoregulation disorders on a recurrent basis with periods of normality between them.

Burns in the Context of a Shared Psychotic Disorder in a Colombian Referral Centre: a Case Report. / Quemaduras en el contexto de un trastorno psicótico compartido en un centro de referencia colombiano: reporte de caso.

INTRODUCTION: Shared paranoid disorder is characterised by the development of psychotic symptoms in people who have a close affective bond with a subject suffering from a mental disorder. This case is the first case of burn injuries reported in the context of this disorder. CASE: We describe a young couple, with a similar pattern of burns caused by contact with a griddle. The injuries are the result of the aggression caused by a relative of one of them, who presented psychotic symptoms, related to the previously undiagnosed spectrum of schizophrenia. CONCLUSIONS: The impact of this condition encompasses social, physical and psychological components, requiring multidisciplinary management and a high index of diagnostic suspicion.

Social isolation of adolescent male rats increases anxiety and K+ -induced dopamine release in the nucleus accumbens: Role of CRF-R1.

Early life adversity can disrupt development leading to emotional and cognitive disorders. This study investigated the effects of social isolation after weaning on anxiety, body weight and locomotion, and on extracellular dopamine (DA) and glutamate (GLU) in the nucleus accumbens (NAc) and their modulation by corticotropin releasing factor receptor 1. On the day of weaning, male rats were housed singly or in groups for 10 consecutive days. Anxiety-like behaviors were assessed by an elevated plus maze (EPM) and an open field test (OF). Neurotransmitter levels were measured by in vivo microdialysis. Single-housed rats spent less time, and entered more, into the closed arms of an EPM than group-housed rats. They also spent less time in the center of an OF, weighed more and showed greater locomotion. In the NAc, no differences in CRF, or in basal extracellular DA or GLU between groups, were observed. A depolarizing stimulus increased DA release in both groups but to higher levels in isolated rats, whereas GLU increased only in single-housed rats. Blocking CRF-R1 receptors with CP-154,526 decreased DA release in single-housed but not in group-housed rats. The corticotropin releasing factor receptor type 1 receptor antagonist also decreased GLU in group-housed animals. These results show that isolating adolescent rats increases anxiety, body weight and ambulation, as well as the sensitivity of dopaminergic neurons to a depolarizing stimulus. This study provides further evidence of the detrimental effects of social isolation during early development and indicates that dysregulation of the CRF system in the NAc may contribute to the pathologies observed.

Health Risk Assessment and Urinary Excretion of Children Exposed to Arsenic through Drinking Water and Soils in Sonora, Mexico.

Environmental arsenic exposure is associated with increased risk of non-cancerous chronic diseases and a variety of cancers in humans. The aims of this study were to carry out for the first time a health risk assessment for two common arsenic exposure routes (drinking water and soil ingestion) in children living in the most important agricultural areas in the Yaqui and Mayo valleys in Sonora, Mexico. Drinking water sampling was conducted in the wells of 57 towns. A cross-sectional study was done in 306 children from 13 villages in the valleys. First morning void urine samples were analyzed for inorganic arsenic (InAs) and monomethyl and dimethyl arsenic (MMA and DMA) by HPLC/ICP-MS. The results showed a wide range of arsenic levels in drinking water between 2.7 and 98.7 µg As/L. Arsenic levels in agricultural and backyard soils were in the range of < 10-27 mg As/kg. The hazard index (HI) = ∑hazard quotient (HQ) for drinking water, agricultural soil, and backyard soil showed values > 1 in 100% of the study towns, and the carcinogenic risk (CR) was greater than 1E-04 in 85%. The average of arsenic excreted in urine was 31.7 µg As/L, and DMA had the highest proportion in urine, with averages of 77.8%, followed by InAs and MMA with 11.4 and 10.9%, respectively, percentages similar to those reported in the literature. Additionally, positive correlations between urinary arsenic levels and HI values were found (r = 0.59, P = 0.000). These results indicated that this population is at high risk of developing chronic diseases including cancer.

Complicaciones postquirúrgicas en intervenciones correctivas de labio y paladar hendido en pacientes pediátricos de un hospital de tercer nivel en Bucaramanga, Colombia 2013-2016 / Complications following surgical treatment of cleft lip and palate in pediatric patients of a third-level hospital in Bucaramanga, Colombia 2013-2016

Resumen Introducción: las hendiduras orofaciales son las malformaciones congénitas de cabeza y cuello más frecuentes en el mundo, con gran importancia epidemiológica por su alto impacto sobre la calidad de vida de la población. Este impacto está dado en gran parte por la presencia de complicaciones postquirúrgicas, por lo que es importante conocerlas, con el fin de aplicar estrategias de prevención o de corrección temprana. Objetivo: identificar las principales complicaciones posquirúrgicas de la cirugía correctiva de labio hendido, paladar hendido o ambos, en un hospital de tercer nivel en Bucaramanga, Santander, Colombia. Materiales y métodos: estudio observacional descriptivo de corte transversal. Se obtuvo la información de los registros de historias clínicas médicas, de pacientes cuya intervención quirúrgica fue realizada durante el período de enero de 2013 a diciembre de 2016. Resultados: se obtuvieron registros de 55 pacientes. La presentación conjunta de labio y paladar hendido fue la anomalía craneoencefálica más frecuente (70,9%). La complicación más frecuente fue la fístula oronasal (23,9% de pacientes con compromiso del paladar), seguida por la dehiscencia de la herida quirúrgica (3,6%). Se encontró un mayor porcentaje de complicaciones postquirúrgicas en el sexo masculino. Conclusión: la complicación postquirúrgica de corrección de labio y/o paladar hendido más frecuente encontrada en la muestra fue la fístula oronasal. MÉD.UIS. 2018;31(2):25-32.

Abstract Introduction: the orofacial clefts are the most frequent congenital malformations of the head and neck in the world, with great epidemiological importance for their impact on the quality of life of the population. This impact is largely due to the presence of postsurgical complications, which is why it is important to know them, in order to apply prevention strategies or early correction. Objective: to identify the main complications following surgical treatment of cleft lip, cleft palate or both, in a third level hospital in Bucaramanga, Santander, Colombia. Materials and methods: descriptive cross-sectional study. The information was obtained from the medical records of patients whose surgical intervention was performed during the period from january 2013 to december 2016. Results: records of 55 patients were obtained. The joint presentation of cleft lip and palate was the most frequent craniofacial anomaly (70.9%). The most frequent complication was oronasal fistula (23.9% of patients with compromised palate), followed by dehiscence of the surgical wound (3.6%). A higher percentage of postoperative complications was found in the male sex. Conclusion: the postoperative complication of lip and/or cleft palate correction most frequently found in the sample was the oronasal fistula. MÉD.UIS. 2018;31(2):25-32.

Source apportionment and environmental fate of lead chromates in atmospheric dust in arid environments.

The environmental fate of lead derived from traffic paint has been poorly studied in developing countries, mainly in arid zones. For this purpose, a developing city located in the Sonoran desert (Hermosillo, Mexico), was chosen to conduct a study. In this paper the lead chromate (crocoite) sources in atmospheric dust were addressed using a combination of Raman microspectroscopy, X-ray diffraction, scanning electron microscopy (SEM), and Pb isotope measurements. A high concentration of Pb and Cr as micro- and nanostructured pigments of crocoite is reported in yellow traffic paint (n=80), road dust (n=146), settled dust in roofs (n=21), and atmospheric dust (n=20) from a developing city located in the Sonoran Desert. 10 samples of peri-urban soils were collected for local geochemical background. The paint photodegradation and erosion of the asphaltic cover are enhanced by the climate, and the presence of the mineral crocoite (PbCrO4) in road dust with an aerodynamic diameter ranging from 100nm to 2µm suggests its integration into the atmosphere by wind resuspension processes. A positive PbCr correlation (R2=0.977) was found for all studied samples, suggesting a common source. The Pb-isotope data show signatures in atmospheric dust as a product of the mixing of two end members: i) local soils and ii) crocoite crystals as pigments in paint. The presence of lead chromates in atmospheric dust has not been previously documented in Latin America, and it represents an unknown health risk to the exposed population because the identified size of crystals can reach the deepest part of lungs.

Causas y sobrevida en pacientes quemados en el centro de referencia del nororiente de Colombia / Agent and survival in burn patients on the referral center of northeastern Colombia

Introducción y Objetivo. En el mundo, las quemaduras son causa importante de morbilidad y responsables del fallecimiento de más de 300.000 personas al año. Más del 90% de estas muertes ocurren en países con ingresos bajos o medios. El objetivo de este estudio es caracterizar los pacientes quemados hospitalizados en el centro de referencia para el nororiente de Colombia, el Hospital Universitario de Santander, en Bucaramanga. Material y Método. Realizamos un estudio observacional, descriptivo y longitudinal, con información tomada de historias clínicas de pacientes quemados hospitalizados en el Hospital Universitario de Santander en un periodo de 12 meses. Obtuvimos información sociodemográfica y médica. Llevamos a cabo un análisis estadístico con medidas de tendencia central, proporciones, incidencia global y específica, además de densidad de incidencia global y especifica. Resultados. Durante el 2014 se hospitalizaron en el centro de estudio 402 pacientes quemados provenientes de 12 departamentos del país, 234 (58.2%) hombres y 168 (41.8%) mujeres, con edades de entre 6 días y 83 años. Las quemaduras comprometían entre el 1 - 80% de superficie corporal; el 95.5% de los pacientes tenían vinculación con el Sistema General de Seguridad Social Nacional. Los agentes causales incluyeron líquidos calientes (52.5%), fuego (10.0%), gasolina (9.2%), electricidad (7.5%) y químicos (3.7%), entre otros, y produjeron quemaduras de segundo y/o tercer grado. La mediana de la estancia hospitalaria fue de 14 días, con mortalidad acumulada del 1.5% que se relacionó con la profundidad y extensión de la quemadura. Consideramos que el tipo de agente compromete con mayor frecuencia a un grupo etario determinado por las actividades propias de la edad; que la profundidad de la quemadura puede tener relación con el agente causal debido a la temperatura que alcanza; y que la extensión de la quemadura es el único predictor de mortalidad y se relaciona con el tiempo de vida postquemadura. Conclusiones. En el nororiente de Colombia, la población masculina y pediátrica presenta mayor número de quemaduras. Existe una relación entre el agente causal y su grupo etario, donde los líquidos calientes y las quemaduras por contacto comprometen principalmente a la población joven. Los pacientes con mayor superficie corporal quemada presentan mayor riesgo de muerte. Creemos que esta información facilita a los centros de quemados preparar sus instalaciones y dirigir sus recursos teniendo en cuenta la población que esperan atender. Las autoridades civiles podrían usar también esta información para diseñar campañas de prevención dirigidas a esta población (AU)

Background and Objective. Burns are an important cause of morbidity and responsible for more than 300.000 deaths per year worldwide. Over 90% of these deaths occur in countries with low or medium income. The aim of this study is to characterize burned patients admitted to the referral center for northeastern Colombia, at the University Hospital of Santander, Bucaramanga. Methods. This was an observational, descriptive and longitudinal study, in a 12 month period. Sociodemographic and medical data was collected from the medical records of burn patients hospitalized at the referred hospital. Statistical analysis was performed with measures of central tendency, proportions, overall incidence and specific density in addition to overall and specific incidence density. Results. During 2014, 402 burn patients were hospitalized proceeding from 12 states, 234 (58.2%) men and 168 (41.8%) women, ages between 6 days and 83 years. Burns affected 1-80% of body surface; 95.5% of patients had some sort of insurance. Causative agents include hot liquids (52.5%), fire (10.0%), fuel (9.2%), electricity (7.5%) and chemical substances (3.7%) among others; these agents produce second and / or third grade burns, 14 days median hospital stay and cumulative mortality of 1.5% which is related to the depth and extent of the burn. We considerer that agents are related to certain age group because of the activities of the corresponding age; the depth may be related to the causative agent because of the temperature it can reach; and the extent of the burn is the only predictor of mortality and is associated with postburn survival time. Conclusions. In northeastern Colombia, male and pediatric population have a greater number of burn victims. There is a relationship between burning agent and patients age, were scalds and contact burns mainly involve the younger population. Patients with greater burned surface area have increased risk of death. This information facilitates burn centers to prepare their facilities and organize resources according to the patients they expect to treat. Civil authorities could use this information to design prevention campaigns targeting this population (AU)

Infection in burn patients in a referral center in Colombia.

INTRODUCTION: Worldwide, burns are responsible for more than 300,000 deaths annually; infection is a major cause of morbidity and mortality in these patients. Early identification and treatment of infection improves outcome. Toward this end it's necessary to identify the institutions flora and organisms that most frequently produces infection. OBJECTIVES: To characterize infections developed by burn patients hospitalized at the University Hospital of Santander (HUS). METHODOLOGY: Burn patients hospitalized in the HUS from January 1 to December 2014 were followed. Medical information regarding infections, laboratory and pathology reports were obtained. Statistical analysis with measures of central tendency, proportions, global and specific incidence density plus overall and specific incidence was obtained. For the microbiological profile proportions were established. RESULTS: 402 burn patients were included, 234 (58.2%) men and 168 (41.8%) women, aged between 6 days and 83 years, median 12.5 years. The burn agents include scald (52.5%), fire (10.0%), gasoline (9.2%), electricity (7.5%), among others. Burn area ranged from 1% to 80% TBS. Cumulative mortality was 1.5%. 27.8% of burned patients had one or more infections. Identified infections include folliculitis (27.0%), urinary tract infection (19.0%), infection of the burn wound (10.4%), pneumonia (8.6%), Central venous catheter (7.4%), bloodstream infection (7.4%) and skin grafts infection (4.3%) among others. Bacteria were responsible for 88.5% of the cases and fungi 11.5%. The most frequently isolated germs were P. aeruginosa, A. baumannii, E. coli, S. aureus and K. pneumoniae. Most gram-negative bacteria were sensitive to Amikacin, gram positive bacteria were sensitive to multiple antibiotics. CONCLUSION: Burns is a severe trauma that occurs in adult and pediatric patients, has several causative agents and can compromise the patient's life. The burned patient is at risk for a variety of infections. According to the type of infection it is possible to infer the most common causative organisms and their antibiotic sensitivity/resistance which allow a directed early empiric treatment.

Caracterización de las quemaduras por sustancias químicas en el Hospital Universitario de Santander, Bucaramanga, Colombia, entre 2009 y 2014 / Characterization of chemical burns at the Hospital Universitario de Santander, Bucaramanga, Colombia, between 2009 and 2014

las quemaduras por sustancias químicas son consideradas lesiones graves por su alto potencial de causar daño local y sistémico,representan entre el 2,4% y el 10,7% de los pacientes admitidos en las unidades de quemados, con una mortalidad asociada del 30%.La literatura disponible en latinoamérica es escasa. Objetivo: el objetivo del estudio es determinar las características clínicas y epidemiológicas de los pacientes con quemadurasquímicas atendidos en la Unidad de Quemados del Hospital Universitario de Santander, Bucaramanga, Colombia. Materiales y métodos: se realizó un estudio de tipo observacional,descriptivo, retrospectivo, en el cual se incluyeron los pacientes que presentaron quemaduras por agentes químicos entre el 1 de enero de 2009 hasta 31 de diciembre de 2014; se incluyeron 29 pacientes. Resultados: las quemaduras químicas representaron el 1,5% de todas las quemaduras;predominio en el género masculino 17 casos;todas con una profundidad grado II y III; las extensiones no superaron el 25% de la superficie corporal total; el sitio anatómico más comprometido fue el miembro superior; hubo mayor asociación con accidentes de tipo laboralcon 16 casos; los ácidos como el principal agente químico implicado con 17 casos y 5 lesiones por agresión; 19 ameritaron manejo quirúrgico. Conclusiones: las quemaduras por sustancias químicas representan un porcentaje pequeño pero significativo de las quemaduras, existiendo una clara asociación a situaciones accidentales por falta de capacitación en la manipulación adecuada de sustancias químicas, lo que plantea la necesidad de tomar medidas de prevención primaria...

Chemical Burns are serious injuriesdue to their high potential to cause local andsystemic damage. They represent between 2.4%and 10.7% of the patients admitted to burn units,and have an associated mortality of 30%. Theavailable literature on Latin America is scarce.Objective: the main objective of the study is todetermine the epidemiological and clinicalcharacteristics of patients with chemical burnstreated at Hospital Universitario de Santander burnunit, in Bucaramanga, Colombia. Methods: thiswas an observational, descriptive, andretrospective study, which included patients whopresented with burns by chemical agents betweenJanuary 1, 2009 to December 31, 2014; 29patients were included. Results: chemical burnsaccounted for 1.5% of all burns; 17 cases weremale gender; all were II and III degree burns; totalbody surface did not exceed 25%. The mostaffected site was the upper limb; there was agreater association with work related accidentswith 16 cases; acids were the principal chemicalagent involved with 17 cases and there wasencountered 5 injuries by assault; 19 patientsrequired surgical intervention. Conclusions:chemical burns represent a small but significantpercentage of burns, there is a clear association toaccidental situations due to lack of training in theproper handling of chemicals, raising the need forprimary prevention measures...

El estudio de casos como método problémico en ciencias médicas: una experiencia necesaria / The case study as a problem-solving method in medical sciences: a necessary experience

El método de casos o estudio de casos se considera propicio para aprehender una situación compleja; se basa en su interpretación la cual se obtiene a través de la descripción y el análisis de cada una de sus partes, asumidas como un conjunto y dentro de su contexto.Entre sus ventajas se menciona que favorece el aprendizaje por descubrimiento, anima al alumno a hacer preguntas, formular sus propias respuestas y a deducir principios a partir de ejemplos prácticos o experiencias; a pesar de ser empleado en variados campos del conocimiento, en la educación médica se aplica poco a través de los informes o reportes decaso. La autora comunica las experiencias docentes de su uso y sugiere que se valore su efectividad en el proceso de formación de los profesionales de la salud(AU)

Intubación submental: experiencia con 30 casos / Submental intubation: experience with 30 cases

Introducción. Cuando un paciente se encuentra politraumatizado, involucrando fracturas serias en la región maxilofacial, así como en la base del cráneo, se opta por realizar una traqueostomía con el fin de permitir un abordaje simultáneo para los diferentes tercios faciales afectados. La intubación submental ofrece una alternativa a dicho manejo de la vía aérea, significando menor riesgo para el paciente por su seguridad y versatilidad en el manejo de las fracturas nasales y el establecimiento de la oclusión. Materiales. Un total de 30 pacientes con diferente afección de los tercios faciales (superior, medio e inferior) fueron tratados por nuestro equipo, llevando a cabo una intubación submental para mantener la vía aérea. Las fracturas afectaban los huesos nasales y la oclusión dentaria. Resultados. En todos los casos se logró una adecuada reducción de las fracturas nasales y obtención de la oclusión dental correcta, sin presentar eventualidades durante o después de la intubación mencionada. Conclusiones. La intubación submental es una buena alternativa para poder tratar adecuadamente a los pacientes politraumatizados con afección de la cavidad nasal y oral sin tener que realizar una traqueostomía en casos que no la requieran (AU)

Introduction. When a patient has multiple injuries, involving serious fractures in the maxillofacial region and base of skull, a tracheostomy is often performed to approach the different affected facial thirds simultaneously. Submental intubation offers an alternative to this type of airway management, involving a decreased risk for the patient due to its safety and versatility in treating nasal fractures and re-establishment of dental occlusion. Materials. A total of 30 patients with different degrees of involvement of the facial thirds (superior, middle and inferior) were treated by our team, performing a submental intubation to maintain the airway. These fractures affected nasal bones and dental occlusion. Results. In all cases we accomplished an adequate reduction of nasal fractures and obtained an accurate dental occlusion, with no incidents during or after this intubation. Conclusions. Submental intubation is a good alternative to treat multiple injury patients who have nasal and oral cavities involvement, avoiding the use of tracheostomy in cases that do not need it (AU)