Stress-Charge Nonlinear Physical Description and Tensor Symmetries for Piezoelectric Materials.

Nonlinear piezoelectric materials are raised as a great replacement for devices that require low power consumption, high sensitivity, and accurate transduction, fitting with the demanding requirements of new technologies such as the Fifth-Generation of telecommunications (5G), the Internet of Things (IoT), and modern radio frequency (RF) applications. In this work, the state equations that correctly predict the nonlinear piezoelectric phenomena observed experimentally are presented. Furthermore, we developed a fast methodology to implement the state equations in the main FEM simulation software, allowing an easy design and characterization of this type of device, as the symmetry structures for high-order tensors are shown and explained. The operation regime of each high-order tensor is discussed and connected with the main nonlinear phenomena reported in the literature. Finally, to demonstrate our theoretical deductions, we used the experimental measurements, which presented the nonlinear effects, which were reproduced through simulations, obtaining maximum percent errors for the effective elasticity constants, relative effective permittivity, and resonance frequencies of 0.79%, 2.9%, and 0.3%, respectively, giving a proof of the potential of the nonlinear state equations presented for the unifying of all nonlinear phenomena observed in the piezoelectric devices.

Effect of Shamiri Layperson-Provided Intervention vs Study Skills Control Intervention for Depression and Anxiety Symptoms in Adolescents in Kenya: A Randomized Clinical Trial.

Importance: Low-cost interventions for adolescent depression and anxiety are needed in low-resource countries such as those in Sub-Saharan Africa. Objective: To assess whether Shamiri, a 4-week layperson-delivered group intervention that teaches growth mindset, gratitude, and value affirmation, can alleviate depression and anxiety symptoms in symptomatic Kenyan adolescents. Design, Setting, and Participants: This school-based randomized clinical trial included outcomes assessed at baseline, posttreatment, and 2-week and 7-month follow-up from 4 secondary schools in Nairobi and Kiambu County, Kenya. Adolescents aged 13 to 18 years with elevated symptoms on standardized depression or anxiety measures were eligible. Intent-to-treat analyses were used to analyze effects. Recruitment took place in June 2019; follow-up data were collected in August 2019 and February 2020. Intervention: Adolescents were randomized to the Shamiri intervention or to a study skills control. All adolescents in both conditions met in groups (mean group size, 9) for 60 minutes per week for 4 weeks. Main Outcomes and Measures: Primary outcomes were depression (Patient Health Questionnaire-8 item) and anxiety (Generalized Anxiety Disorder-7 item) symptoms. Analyses of imputed data were hypothesized to reveal significant reductions in depression and anxiety symptoms for adolescents assigned to Shamiri compared with those in the study skills group. Results: Of 413 adolescents, 205 (49.6%) were randomized to Shamiri and 208 (50.4%) to study skills. The mean (SD) age was 15.5 (1.2) years, and 268 (65.21%) were female. A total of 307 youths completed the 4-week intervention. Both Shamiri and study skills were rated highly useful (4.8/5.0) and reduced symptoms of depression and anxiety, but analyses with imputed data revealed that youths receiving Shamiri showed greater reductions in depressive symptoms at posttreatment (Cohen d = 0.35 [95% CI, 0.09-0.60]), 2-week follow-up (Cohen d = 0.28 [95% CI, 0.04-0.54]), and 7-month follow-up (Cohen d = 0.45 [95% CI, 0.19-0.71]) and greater reductions in anxiety symptoms at posttreatment (Cohen d = 0.37 [95% CI, 0.11-0.63]), 2-week follow-up (Cohen d = 0.26 [95% CI, -0.01 to 0.53]), and 7-month follow-up (Cohen d = 0.44 [95% CI, 0.18-0.71]). Conclusions and Relevance: Both the Shamiri intervention and a study skills control group reduced depression and anxiety symptoms; the low-cost Shamiri intervention had a greater effect, with effects lasting at least 7 months. If attrition is reduced and the clinical significance of outcome differences is established, this kind of intervention may prove useful in other global settings where there are limited resources, mental illness stigma, or a shortage of professionals and limited access to mental health care. Trial Registration: Pan-African Clinical Trials Registry Identifier: PACTR201906525818462.

The Shamiri group intervention for adolescent anxiety and depression: study protocol for a randomized controlled trial of a lay-provider-delivered, school-based intervention in Kenya.

BACKGROUND: Developing low-cost, socio-culturally appropriate, and scalable interventions for youth depression and anxiety symptoms in low-income regions such as countries in sub-Saharan Africa is a global mental health priority. We developed and intend to evaluate one such intervention for adolescent depression and anxiety in Kenya. The intervention, named Shamiri (a Swahili word for "thrive"), draws upon evidence-based components of brief interventions that involve nonclinical principles rather than treatment of psychopathology (e.g., growth mindset, gratitude, and virtues). METHODS: Four hundred twenty Kenyan adolescents (ages 13-18) with clinically elevated depression and/or anxiety symptoms will be randomized to either the 4-week Shamiri group intervention or a group study-skills control intervention of equal duration and dosage. Participating adolescents will meet in groups of 8-15, led by a high-school graduate trained to deliver Shamiri as a lay-provider. Adolescents will self-report primary outcome measures (depression-measured by the PHQ-8, and anxiety symptoms-measured by the GAD-7) and secondary outcome measures (perceived social support, perceived academic control, self-reported optimism and happiness, loneliness, and academic grades) at the 2-week intervention midpoint, 4-week post-intervention endpoint, and 2-week post-intervention follow-up. We predict that adolescents in the Shamiri group, when compared to the study-skills control group, will show greater improvements in primary outcomes and secondary outcomes. DISCUSSION: Results may suggest that a brief, lay-provider delivered, school-based intervention may reduce depression and anxiety symptoms, improving academic outcomes and other psychosocial outcomes in adolescents with clinically-elevated symptoms in sub-Saharan Africa. TRIAL REGISTRATION: Pan African Clinical Trials Registry PACTR201906525818462 . Registered on 12 June 2019.

Installing oncofertility programs for common cancers in limited resource settings (Repro-Can-OPEN Study): An extrapolation during the global crisis of Coronavirus (COVID-19) pandemic.

PURPOSE: The state of limited resource settings that Coronavirus (COVID-19) pandemic has created globally should be taken seriously into account especially in healthcare sector. In oncofertility, patients should receive their fertility preservation treatments urgently even in limited resource settings before initiation of anticancer therapy. Therefore, it is very crucial to learn more about oncofertility practice in limited resource settings such as in developing countries that suffer often from shortage of healthcare services provided to young patients with cancer. METHODS: As an extrapolation during the global crisis of COVID-19 pandemic, we surveyed oncofertility centers from 14 developing countries (Egypt, Tunisia, Brazil, Peru, Panama, Mexico, Colombia, Guatemala, Argentina, Chile, Nigeria, South Africa, Saudi Arabia, and India). Survey questionnaire included questions on the availability and degree of utilization of fertility preservation options in case of childhood cancer, breast cancer, and blood cancer. RESULTS: All surveyed centers responded to all questions. Responses and their calculated oncofertility scores showed different domestic standards for oncofertility practice in case of childhood cancer, breast cancer, and blood cancer in the developing countries under limited resource settings. CONCLUSIONS: Medical practice in limited resource settings has become a critical topic especially after the global crisis of COVID-19 pandemic. Understanding the resources necessary to provide oncofertility treatments is important until the current COVID-19 pandemic resolves. Lessons learned will be valuable to future potential worldwide disruptions due to infectious diseases or other global crises.

Single-session digital intervention for adolescent depression, anxiety, and well-being: Outcomes of a randomized controlled trial with Kenyan adolescents.

BACKGROUND: Adolescent depression and anxiety symptoms are prevalent in sub-Saharan African countries, yet treatment options are scarce, and stigma limits help-seeking. Brief, computerized single-session interventions (SSIs) that contain empirically supported stigma-reducing elements may help expand access to treatment. We developed and evaluated such an intervention for Kenyan adolescents. METHOD: High school students (N = 103, age 13-18) were randomized to a digital SSI Shamiri-Digital (Shamiri means "thrive" in Kiswahili) or a study-skills control intervention. Shamiri-Digital consisted of reading and writing activities about 3 concepts: growth mindset, gratitude, and value affirmation. Both Shamiri-Digital and the study-skills control condition were delivered electronically in schools. RESULTS: Compared to the control, Shamiri-Digital produced a greater reduction in adolescent depressive symptoms in both the full sample (p = .028, d = 0.50) and a subsample of youths with moderate to severe depression symptoms (p = .010, d = 0.83) from baseline to 2-week follow-up. The effects exceed the mean effects reported in meta-analyses of full-length, face-to-face psychotherapy for youth depression. There were no significant effects on anxiety symptoms, well-being, or happiness. CONCLUSION: This is the first report that a brief, computerized SSI may reduce depressive symptoms in adolescents in sub-Saharan Africa. Replication trials with extended follow-ups will help gauge the strength and durability of these effects. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Neumoperitoneo poscolonoscopia sin evidencia de perforación colónica / Post-Colonoscopy neumoperitoneum without evidence of colonic perforation

Objetivo: Reportar el caso de una complicación poscolonoscopia de tratamiento complejo. Caso clínico: Presentamos el caso de una mujer de 82 años, a quien se practicó una colonoscopia total por sangrado rectal, reportando úlcera anal. Dos días después presentó dolor abdominal y distensión abdominal. En las imágenes se encontró gran neumoperitoneo; se realizó laparotomía exploradora sin encontrar lesión en el colon. Presentó buena evolución postoperatoria. Se hace una revisión de la literatura respectiva.

Aim: To report a case of one of the most complex complication post-colonoscopy and is treatment. Case report: We report the case of a 82 years old woman, who was taken to complete colonoscopy for rectal bleeding, then reporting an anal ulcer. Two days later, she has abdominal pain and bloating. In images she has a great pneumoperitoneum. At laparotomy it was not found any injury to the colon. She has a good post-operative evolution. Respective literature review is done.

Freshwater fish faunas, habitats and conservation challenges in the Caribbean river basins of north-western South America.

The remarkable fish diversity in the Caribbean rivers of north-western South America evolved under the influences of the dramatic environmental changes of neogene northern South America, including the Quechua Orogeny and Pleistocene climate oscillations. Although this region is not the richest in South America, endemism is very high. Fish assemblage structure is unique to each of the four aquatic systems identified (rivers, streams, floodplain lakes and reservoirs) and community dynamics are highly synchronized with the mono-modal or bi-modal flooding pulse of the rainy seasons. The highly seasonal multispecies fishery is based on migratory species. Freshwater fish conservation is a challenge for Colombian environmental institutions because the Caribbean trans-Andean basins are the focus of the economic development of Colombian society, so management measures must be directed to protect aquatic habitat and their connectivity. These two management strategies are the only way for helping fish species conservation and sustainable fisheries.

Association of the bovine growth hormone gene with Holstein cattle reproductive parameters / Asociación del gen de la hormona de crecimiento bovino con parámetros reproductivos en ganado Holstein

Objective. To determine the association of intron 3 polymorphism of the bovine growth hormone (BGH) gene, with age at first service, first birth, first postpartum service and second birth in a population of Holstein cows in the state of Antioquia. Materials and methods. The study was conducted on 408 Holstein cows in 8 herds. Genotyping was performed using PCR-RFLP technique with DNA extracted from peripheral blood by the salting out technique. The Phenotypic information used was collected for 4 years, from a dairy production control program. To determine the association between characteristics and gene polymorphism, parametric statistical analyzes were performed as generalized linear models and linear regression analysis. Results. Allele frequency (positive) was 0.91 and was 0.09 for (negative) allele. Genotypic frequencies were 0.77, 0.2 and 0.03 for (positive/positive), (positive/negative) and (negative/negative) respectively. There were significant differences between the mean of age at first service, age at first birth, age at first postpartum service and age at second birth. For all of the (negative/negative) genotype characteristics there were greater ages for each event. Conclusions. These results suggest that intron-3 polymorphism of the BGH gene is associated with reproductive traits, facilitating the selection of individuals with favorable genotypes for use in breeding programs.

Objetivo. Determinar la asociación del polimorfismo del intrón 3 del gen de la hormona de crecimiento bovino (BGH) con las edades al primer servicio, primer parto, primer servicio posparto y segundo parto en una población de vacas Holstein del departamento de Antioquia. Materiales y métodos. El estudio se realizó con 408 vacas Holstein ubicadas en 8 hatos. La genotipificación se llevó a cabo usando la técnica de PCR-RFLP con ADN extraído de sangre periférica mediante la técnica de salting out. La información fenotípica utilizada fue recopilada durante 4 años, a partir de un programa de control de producción lechera. Para determinar la asociación entre las características y el polimorfismo del gen, se realizaron análisis estadísticos paramétricos mediante modelos lineales generalizados y análisis de regresión lineal. Resultados. La frecuencia para el alelo (positivo) fue de 0.91 y para el alelo (negativo) fue de 0.09. Las frecuencias genotípicas fueron 0.77, 0.2 y 0.03 para (positivo/positivo), (positivo/negativo) y (negativo/negativo) respectivamente. Se presentaron diferencias significativas entre las medias de la edad al primer servicio, la edad al primer parto, edad al primer servicio postparto y edad al segundo parto. Para todas las características el genotipo (negativo/negativo) presentó edades más tardías para cada eventos. Conclusiones. Estos resultados sugieren que el polimorfismo del intrón 3 del gen BGH, está asociado con características de tipo reproductivo, facilitando la implementación de un programa de selección de individuos con genotipos favorables, para su uso en programas de mejoramiento genético animal.

Caracterización espacial y biogeográfica de las asociaciones de macroalgas de Bahía del Rincón, Baja California Sur, México / Spatial and biogeographic characterization of macroalgal assemblages from Bahía del Rincón, Baja California Sur, Mexico

Macroalgal studies in Baja California Sur have dealt mainly with occurrence and seasonality, but some areas are poorly known even for these basic data. Bahía del Rincón-La Rivera is an important high-productivity fisheries area where coastal infrastructure development is under way. A spatial characterization of the marine flora from Bahía del Rincón-La Rivera was done by intensive sampling at different depths and localities with skin and SCUBA diving. At least 500m2 were surveyed in each site. Additionally, quantitative sampling was done in ten random 25 cm2 quadrates per site. In the intertidal section, density and cover estimates were used. We also investigated the historical records and geographical affinities. A total of 72 species were identified (most were red algae: 62%). We found no general trend in the biogeographical affinities, which varied with each taxonomic group. Most brown algae species were tropical-endemic; red algae temperate- cosmopolite and green algae tropical-cosmopolite. In the spatial assemblage structure we found a high similarity between the intertidal areas, but a low similarity in shallow or deeper areas (3-5 m). This pattern was the same when we compared the abundance of the main species. We suggest that there are significant spatial differences in recruitment and development of the assemblages in relation to vertical distribution (depth)and position along the shore. There is a clear-cut Gelidium-Jania belt in the intertidal zone and a Padina-Dictyota belt below the low tide. Sporadic and year-round species occur in the intertidal zone, annual and perennial species below the low tide line. Sites differ in recruitment and this affects the abundance of other species (such as coraline and Caulerpa species). Temperature and sedimentation affect seasonality, but community structure is relatively constant throughout the year

Se caracterizó la flora marina de la zona de Bahía del Rincón -La Rivera por medio de prospecciones intensivas en diferentes localidades a varias profundidades. Además, se realizó un análisis intenso de la literatura y por este mismo medio la determinación de las afinidades geográficas de las especies. En total se encontraron 72 especies, donde la mayor proporción (62%) correspondió a las algas rojas. En el caso de las afinidades biogeográficas se observó que la mayor proporción varió en función de la división, donde para algas cafés las predominantes fueron de naturaleza tropical/ endémica y para las algas rojas fueron las templadas/ cosmopolitas. Espacialmente se encontró una alta similitud entre las zonas someras estudiadas más no así entre las someras y profundas donde existen diferencias significativas. En el caso de la zona intermareal se determinaron diferencias significativas con áreas submareales y entre sitios de la zona somera y profunda basados en las abundancias de los principales taxa. Con base en los resultados se sugiere que existen diferencias verticales en reclutamiento y desarrollo de las poblaciones en relación a su distribución

[Spatial and biogeographic characterization of macroalgal assemblages from Bahía del Rincón, Baja California Sur, Mexico]. / Caracterización espacial y biogeográfica de las asociaciones de macroalgas de Bahía del Rincón, Baja California Sur, México.

Macroalgal studies in Baja California Sur have dealt mainly with occurrence and seasonality, but some areas are poorly known even for these basic data. Bahia del Rincón-La Rivera is an important high-productivity fisheries area where coastal infrastructure development is under way. A spatial characterization of the marine flora from Bahia del Rincón-La Rivera was done by intensive sampling at different depths and localities with skin and SCUBA diving. At least 500 m2 were surveyed in each site. Additionally. quantitative sampling was done in ten random 25 cm2 quadrates per site. In the intertidal section, density and cover estimates were used. We also investigated the historical records and geographical affinities. A total of 72 species were identified (most were red algae: 62%). We found no general trend in the biogeographical affinities, which varied with each taxonomic group. Most brown algae species were tropical-endemic; red algae temperate-cosmopolite and green algae tropical-cosmopolite. In the spatial assemblage structure we found a high similarity between the intertidal areas, but a low similarity in shallow or deeper areas (3-5 m). This pattern was the same when we compared the abundance of the main species. We suggest that there are significant spatial differences in recruitment and development of the assemblages in relation to vertical distribution (depth) and position along the shore. There is a clear-cut Gelidium-Jania belt in the intertidal zone and a Padina-Dictyota belt below the low tide. Sporadic and year-round species occur in the intertidal zone, annual and perennial species below the low tide line. Sites differ in recruitment and this affects the abundance of other species (such as coraline and Caulerpa species). Temperature and sedimentation affect seasonality, but community structure is relatively constant throughout the year.

A bioactive biflavonoid from Campnosperma panamense.

Lanaroflavone (1), a biflavonoid isolated from the methanol extract of the aerial part of Campnosperma panamense by bioguided fractionation, has been assessed for in vitro antiprotozoal activity. Lanaroflavone showed both antimalarial and leishmanicidal activities, but was inactive against Chagas disease vector, Trypanosoma cruzi.

¿Se justifica seguir enseñando pérdida de resistencia utilizando aire en lugar de suero salino para identificar el espacio epidural? a propósito de un caso de neumoencéfalo / Is it justi fied to keep showing loss of resistance by air in or der to identifity the epidural space, instead of saline? as regards a pneumoencephalon case

Las técnicas epidurales anestésicas y analgésicas fundamentan su éxito en gran medida en la correcta identificación del espacio epidural, siendo la pérdida de la resistencia por medio de aire o solución salina la técnica más empleada. A pesar de las múltiples complicaciones asociadas al aire, este continúa siendo utilizado ampliamente. Se describe un neumoencéfalo, complicación relacionada con el uso de aire, discutiendo las otras complicaciones existentes. Cuestionamos además la enseñanza continua del método con aire si existe una alternativa segura como lo es el salino. Las técnicas epidurales anestésicas y analgésicas fundamentan su éxito en gran medida en la correcta identificación del espacio epidural, siendo la pérdida de la resistencia por medio de aire o solución salina la técnica más empleada. A pesar de las múltiples complicaciones asociadas al aire, este continúa siendo utilizado ampliamente. Se describe un neumoencéfalo, complicación relacionada con el uso de aire, discutiendo las otras complicaciones existentes. Cuestionamos además la enseñanza continua del método con aire si existe una alternativa segura como lo es el salino (AU)

Antiprotozoal activities of Colombian plants.

In our search for therapeutical alternatives for antiprotozoal chemotherapy, we collected a selection of 44 plants from western Colombia upon ethnopharmacological and chemotaxonomic considerations. Polar and apolar extracts of these species were examined for antimalarial activity using in vitro tests with two clones of Plasmodium falciparum. Leishmanicidal and trypanocidal activity were determined in vitro using promastigote and amastigote forms of several strains of Leishmania sp. and epimastigotes of Trypanosoma cruzi. Among the selected plants, the 15 following species showed good or very good antiprotozoal activity in vitro: Aspidosperma megalocarpon, Campnosperma panamense, Conobea scoparioides, Guarea polymera, Guarea guidonia, Guatteria amplifolia, Huberodendron patinoi, Hygrophila guianensis, Jacaranda caucana, Marila laxiflora, Otoba novogranatensis, Otoba parviflora, Protium amplium, Swinglea glutinosa and Tabernaemontana obliqua. Cytotoxicity was assessed in U-937 cells and the ratio of cytotoxicity to antiprotozoal activity was determined for the active extracts. Ten extracts from eight species showed selectivity indexes > or = 10. Among the extracts that showed leishmanicidal activity, the methylene chloride extract of leaves from C. scoparioides showed a selectivity index in the same range that the one of the Glucantime control. Several of the active leishmanicidal plants are traditionally used against leishmaniasis by the population of the concerned area.

[Risk factors associated with nosocomial bacteremia in low birth weight neonates. Grady Memorial Hospital, Atlanta]. / Factores de riesgo asociados con bacteriemia nosocomial en recién nacidos de bajo peso al nacimiento. Hospital Grady Memorial, Atlanta.

BACKGROUND: Nosocomial bloodstream infections occur frequently in Neonatal Intensive Care Units and are associated with recognized and unrecognized risk factors. Little has been published regarding risk factors for bloodstream infections in low birth weight neonates. OBJECTIVE: To investigate risk factors for bloodstream infection in neonates < 1,500 g admitted at a Neonatal Intensive Care Unit. METHODS: A prospective study was undertaken in low birth weight neonates (< 1,500g) during a 22 months period. Bivariant, and logistic regresion (stepwise procedure) analysis was used to determine the significance association of bloodstream infection and perinatal and nosocomial risk factors. RESULTS: A total of 72 patiens with nosocomial bacteriemia and 147 non bacteriemic patients were studied. Independent risk factors associated with bloodstream infection were birth weight, persistence of umbilical catheter > 7 days and persistence of peripheral arterial catheter > 1 day. CONCLUSIONS: The uses of umbilical catheter > 7 days, peripheral arterial catheter > 1 day and birth weight < 1,500 g were significant determinants of nosocomial bloodstream infection risk. Because of the importance of invasive procedures as a source of nosocomial bloodstream infections, the lines duration needs to be reviewed with the aim of reducing the incidence of blood stream infection.

Apolipoprotein E genotyping in a sample of Colombian patients with Alzheimer's disease.

Apolipoprotein E e4 (APOEe4) allele has been associated with an increased risk for Alzheimer's disease (AD) in diverse populations. Few studies have been carried out in Hispano-Americans and results are inconclusive due to ethnic diversity. This study determined the frequency of APOE alleles in a group of 61 Caucasian-Mestizos patients with probable AD, and 61 age- and sex-matched controls. APOEe4 frequency was 36.8% for patients, and 8.2% for controls (P < 0.0001; OR 7.6). Genotype frequencies differ between the two groups (P < 0.0001). Genotype 3/3 was the most common. Frequency of genotypes 3/4, 4/4 and 2/4 were higher in patients than in the controls. Our results show a highly significant association of APOEe4 with AD, and implies the importance of APOEe4 as a risk factor in this population.

Tumoración blanda en cráneo / Soft tissue cranial tumor

No disponible

Factores de riesgo asociados con bacteriemia nosocomial en recién nacidos de bajo peso al nacimiento. Hospital Grady Memorial, Atlanta / Risk factors associated with nosocomial bacteremia in low birth weight neonates. Grady Memorial Hospital, Atlanta

Introducción: La bacteriemia nosocomial es una causa frecuente de infección nosocomial en los recién nacidos admitidos en las unidades de cuidados intensivos neonatales y está asociada con factores de riesgo, reconocidos y no reconocidos, de infección nosocomial. Aún existen pocas evidencias sobre los factores de riesgo de bacteriemia nosocomial en recién nacidos de bajo peso al nacimiento. Objetivos: Investigar factores de riesgo de bacteriemia nosocomial en neonatos con un peso inferior a 1.500 g ingresados en la unidad de cuidados intensivos neonatal. Métodos: Se realizó un estudio prospectivo en recién nacidos de bajo peso al nacimiento ( 1.500 g) durante 22 meses. Para determinar la asociación estadística entre la bacteriemia nosocomial y los factores de riesgo perinatales y nosocomiales, se llevó a cabo un análisis bivariante de regresión logística (método de regresión por pasos). Resultados: Se estudió a un total de 72 pacientes con bacteriemia nosocomial y 174 sin ella. La permanencia del catéter umbilical un tiempo mayor o igual a 7 días y la permanencia del catéter periférico arterial durante un día o más resultaron ser los factores independientemente asociados con bacteriemia nosocomial. Conclusión: El mantenimiento del catéter umbilical más de 7 días, la permanencia del catéter periférico arterial más de 1 día y el peso al nacimiento inferior a 1.500 g fueron factores determinantes de bacteriemia nosocomial. Por la importancia de estas técnicas invasivas como fuente de bacteriemia nosocomial, es preciso revisar su tiempo de permanencia con el objetivo de disminuir la incidencia de bacteriemia nosocomial (AU)