Waiting time in the premilking holding pen and subsequent lying and walking behaviors of Holstein cows.

The objective of this study was to assess the effect of waiting time (WT) in the premilking holding pen on the subsequent lying and walking behaviors of Holstein cows. A total of 108 cows (multiparous n = 95; primiparous n = 13), milked 3 times/d [AM (0700 h), PM (1500 h), and nighttime (2300 h)] were monitored for individual WT, which was defined as the time elapsed between the entrance of the first cow to the milking stall in a rotary milking system and the entrance of each subsequent cow housed in the same milking pen. Data for lying time (min), standing time (min), lying bouts (no.), and walking behavior (no. of steps) in 15-min intervals were collected using a commercial 3-dimensional accelerometer affixed on the hind left leg of each cow from early to mid lactation. Mean values (min/h, no./h) for each behavior calculated between consecutive milkings were compared among 3 WT categories: cows with WT ≤30 min (WT1), WT 30 to 60 min (WT2), and WT >60 min (WT3). The overall mean (SD) of WT during the study period was 31.2 (23.4) min, and the distribution of WT1, WT2, and WT3 in all cows through the monitoring period was 50.9, 43.3, and 5.7%, respectively. No significant effects were established for overall WT on any of the behaviors under analysis. However, subsequent analysis by milking shift indicated that, during the period following the night milking, cows in WT1 exhibited the shortest lying time, whereas cows in WT3 had the greatest number of lying bouts. No effect of WT category was observed on the number of steps after any of the milking shifts. Results of this study indicate a moderate effect of WT on lying behavior after the nighttime milking. Variables such as temperature-humidity index, parity, and time of day affected cow behavior and should be considered when evaluating the impact of routine management practices, such as milking, on commercial farms.

Middle East respiratory syndrome coronavirus vaccine based on a propagation-defective RNA replicon elicited sterilizing immunity in mice.

Self-amplifying RNA replicons are promising platforms for vaccine generation. Their defects in one or more essential functions for viral replication, particle assembly, or dissemination make them highly safe as vaccines. We previously showed that the deletion of the envelope (E) gene from the Middle East respiratory syndrome coronavirus (MERS-CoV) produces a replication-competent propagation-defective RNA replicon (MERS-CoV-ΔE). Evaluation of this replicon in mice expressing human dipeptidyl peptidase 4, the virus receptor, showed that the single deletion of the E gene generated an attenuated mutant. The combined deletion of the E gene with accessory open reading frames (ORFs) 3, 4a, 4b, and 5 resulted in a highly attenuated propagation-defective RNA replicon (MERS-CoV-Δ[3,4a,4b,5,E]). This RNA replicon induced sterilizing immunity in mice after challenge with a lethal dose of a virulent MERS-CoV, as no histopathological damage or infectious virus was detected in the lungs of challenged mice. The four mutants lacking the E gene were genetically stable, did not recombine with the E gene provided in trans during their passage in cell culture, and showed a propagation-defective phenotype in vivo. In addition, immunization with MERS-CoV-Δ[3,4a,4b,5,E] induced significant levels of neutralizing antibodies, indicating that MERS-CoV RNA replicons are highly safe and promising vaccine candidates.

Anatomy of subcritical submarine flows with a lutocline and an intermediate destruction layer.

Turbidity currents are sediment-laden flows that travel over a sloping bed under a stagnant ambient fluid, driven by the density difference between the current and the ambient. Turbidity currents transport large amounts of carbon, nutrients and fresh water through oceans and play an important role in global geochemical cycling and seafloor ecosystems. Supercritical currents are observed in steeper slopes. Subcritical currents are observed in milder slopes, where the near-bed and interface layers are prevented from interacting across the velocity maximum. Past works show the existence of such a barrier to vertical momentum transfer is essential for the body of the subcritical current to extend over hundreds of kilometers in length without much increase in height. Here we observe the body of subcritical currents to have a three layer structure, where the turbulent near-bed layer and the non-turbulent interface layer are separated by an intermediate layer of negative turbulence production. We explain the mechanism by which this layer prevents the near-bed turbulent structures from penetrating into the interface layer by transferring energy back from turbulence to the mean flow.

Targeted next-generation sequencing of circulating-tumor DNA for tracking minimal residual disease in localized colon cancer.

BACKGROUND: A high percentage of patients diagnosed with localized colon cancer (CC) will relapse after curative treatment. Although pathological staging currently guides our treatment decisions, there are no biomarkers determining minimal residual disease (MRD) and patients are at risk of being undertreated or even overtreated with chemotherapy in this setting. Circulating-tumor DNA (ctDNA) can to be a useful tool to better detect risk of relapse. PATIENTS AND METHODS: One hundred and fifty patients diagnosed with localized CC were prospectively enrolled in our study. Tumor tissue from those patients was sequenced by a custom-targeted next-generation sequencing (NGS) panel to characterize somatic mutations. A minimum variant allele frequency (VAF) of 5% was applied for variant filtering. Orthogonal droplet digital PCR (ddPCR) validation was carried out. We selected known variants with higher VAF to track ctDNA in the plasma samples by ddPCR. RESULTS: NGS found known pathological mutations in 132 (88%) primary tumors. ddPCR showed high concordance with NGS (r = 0.77) for VAF in primary tumors. Detection of ctDNA after surgery and in serial plasma samples during follow-up were associated with poorer disease-free survival (DFS) [hazard ratio (HR), 17.56; log-rank P = 0.0014 and HR, 11.33; log-rank P = 0.0001, respectively]. Tracking at least two variants in plasma increased the ability to identify MRD to 87.5%. ctDNA was the only significantly independent predictor of DFS in multivariable analysis. In patients treated with adjuvant chemotherapy, presence of ctDNA after therapy was associated with early relapse (HR 10.02; log-rank P < 0.0001). Detection of ctDNA at follow-up preceded radiological recurrence with a median lead time of 11.5 months. CONCLUSIONS: Plasma postoperative ctDNA detected MRD and identified patients at high risk of relapse in localized CC. Mutation tracking with more than one variant in serial plasma samples improved our accuracy in predicting MRD.

Molecular Basis of Coronavirus Virulence and Vaccine Development.

Virus vaccines have to be immunogenic, sufficiently stable, safe, and suitable to induce long-lasting immunity. To meet these requirements, vaccine studies need to provide a comprehensive understanding of (i) the protective roles of antiviral B and T-cell-mediated immune responses, (ii) the complexity and plasticity of major viral antigens, and (iii) virus molecular biology and pathogenesis. There are many types of vaccines including subunit vaccines, whole-inactivated virus, vectored, and live-attenuated virus vaccines, each of which featuring specific advantages and limitations. While nonliving virus vaccines have clear advantages in being safe and stable, they may cause side effects and be less efficacious compared to live-attenuated virus vaccines. In most cases, the latter induce long-lasting immunity but they may require special safety measures to prevent reversion to highly virulent viruses following vaccination. The chapter summarizes the recent progress in the development of coronavirus (CoV) vaccines, focusing on two zoonotic CoVs, the severe acute respiratory syndrome CoV (SARS-CoV), and the Middle East respiratory syndrome CoV, both of which cause deadly disease and epidemics in humans. The development of attenuated virus vaccines to combat infections caused by highly pathogenic CoVs was largely based on the identification and characterization of viral virulence proteins that, for example, interfere with the innate and adaptive immune response or are involved in interactions with specific cell types, such as macrophages, dendritic and epithelial cells, and T lymphocytes, thereby modulating antiviral host responses and viral pathogenesis and potentially resulting in deleterious side effects following vaccination.

Diagnóstico bacteriológico de tuberculosis pulmonar mediante fibrobroncoscopía en pacientes con VIH / Bacteriological diagnosis of lung tuberculosis through bronchoscopy in HIV-infected patients

Tuberculosis can be lethal in HIV infected people. Lung is the organ most frequently involved, but clinical and radiological features are not typical of the disease. Diagnostic certification demands acid-fast bacillus microscopy and mycobacterial cultures on sputum. Some patients need bronchoscopy to obtain samples due to insufficient sputum. We reported a 9.1 percent diagnostic yield using bronchoscopy. Clinical suspicion before bronchoscopy had low positive predictive value of tuberculosis (10.8 percent). 47.8 percent of tuberculosis cases were not suspected before this procedure. Tuberculosis patients showed CD4 < 200 cells/mL (48.8 in average) and less use of ART (antiretroviral therapy). Cultures contributed to the diagnosis of 35 percent of tuberculosis cases but with a delay of 30 days. Induced sputum is a less costly alternative to bronchoscopy with a similar diagnostic yield.

La tuberculosis puede ser letal en pacientes infectados por VIH. El compromiso pulmonar es más frecuente en ellos y su cuadro clínico-radiológico no es típico de la enfermedad. El diagnóstico se confirma con baciloscopía y cultivo de Koch en esputo. Los pacientes sin esputo pueden requerir broncoscopía. Encontramos un rendimiento de 9,1 por ciento en diagnóstico de tuberculosis pulmonar por broncoscopía. La sospecha clínica de tuberculosis previa a broncoscopía tuvo bajo valor predictivo positivo (10,8 por ciento). 47,8 por ciento de los pacientes con Tuberculosis no fueron sospechados antes de la broncoscopía por lo que recomendamos este procedimiento en pacientes VIH con alteraciones radiológicas y síntomas respiratorios. Los casos de tuberculosis tenían CD4 < 200 células/mL (promedio 48,8) y menos uso de TAR: terapia antiretroviral. El 35 por ciento de los casos de tuberculosis se diagnosticó por cultivo (demora mínima de 30 días). El esputo inducido es una alternativa a la broncoscopía menos costosa y de similar rendimiento.

Acquisition of a pathogenicity island in an Escherichia coli clinical isolate causing febrile urinary tract infection.

Urinary tract infections (UTI) are less common in men than in women, and uropathogenic Escherichia coli (UPEC) is the most frequent etiological agent. Recurrent UTI in men have often been reported as a relapse with the same strain as the index infection. The persistence of the same E. coli strain within the urinary tract has often been explained by a prostatic focus. The aim of this study was to determine whether recurrence was associated with relapse or reinfection and the possible effect of treatment on the content of virulence factors of the isolates causing these infections. Thirty E. coli isolates were collected from 15 patients with a febrile UTI having a bacteriological recurrence during long-term follow-up. These isolates were analyzed by pulsed-field gel electrophoresis (PFGE) and virulence profiling in order to determine whether they constituted relapse or reinfection. Five recurrences were categorized as relapse and nine as reinfections. The results obtained showed that the horizontal transfer of virulence factors contained in a pathogenicity island had occurred in one isolate. This event is possible in vivo and allows bacteria to become more virulent and, perhaps, cause greater damage. The acquisition of virulence genes by horizontal gene transfer is an ongoing process of evolution that continuously leads to new bacterial pathotypes.

[Prevalence of chronic kidney disease in subjects consulting in urban primary care clinics]. / Prevalencia de enfermedad renal crónica en centros urbanos de atención primaria.

BACKGROUND: Chronic kidney disease (CKD) is a major worldwide public health problem and is associated with increased risk of cardiovascular disease and death. AIM: To assess CKD prevalence in urban Primary Care Services (PCS) of Concepcion, Chile. MATERIAL AND METHODS: The clinical records of 27.894 adults aged 55 ± 18 years (66% females), consulting in outpatient clinics and in whom serum creatinine was measured, with or without assessment of urine albumin levels, were reviewed. The glomerular filtration rate (eGFR) was estimated using the Modification of Diet in Renal Disease (MDRD)-4 equation. CKD was defined as an eGFR < 60 ml/min/1.73 m2 and classified according to the National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NFK-KDOQI) guidelines. RESULTS: Mean eGFR was 77.1 ± 16.3 ml/min/1.73 m2. Twelve percent of subjects had CKD (women, 14.5% and men 7,4%, p < 0,05). The prevalence of stages 3, 4 and 5 of CKD were 11.6, 0.3 and 0.2 % respectively. eGFR was negatively correlated with age ( r = -0,54, p < 0,05). Among patients with an eGFR < 60 ml/min/1.73 m2, 96.3% had eGFR 30-59, 2.3% 15-29 and 1.4 % < of 15. Seventy nine percent were women. 75.1% were aged 65 years or more, 26.8% had a serum creatinine equal or less than 1.0 mg/dL and 40.5% had microalbuminuria. Only 1% of outpatients ascribed to Cardiovascular or Diabetes Programs had the diagnosis of CKD registered. Independent risk predictors of CKD were age > 60 years, female sex and microalbuminuria. CONCLUSIONS: This study showed a high prevalence of CKD in ambulatory patients, mainly among women and older people. The low level of diagnosis of CKD in cardiovascular and diabetes programs is of concern.

Evaluación de plántulas de cardamomo (Elettaria cardamomum (L. ) Maton) por su resistencia in vitro al filtrado de cultivo de Fusarium oxysporum Link / Seedlings of cardamom (Elettaria cardamomum (L. ) Maton) evaluation by resistance in vitro at culture filtrates of Fusarium oxysporum Link

El Fusarium oxysporum Link es el causante de la pudrición basal en el cardamomo. En el presente trabajo se evalúa el efecto fitotóxico del filtrado crudo del hongo, para seleccionar variantes somaclonales de cardamomo resistentes al mismo en pruebas de patogenicidad en invernadero. Mediante los resultados de mortalidad se seleccionaron el clon 5 y el aislado 4 como los de mayor interacción de susceptibilidad – virulencia. De plántulas madres mantenidas en medio de crecimiento acelerado, se inocularon mensualmente 25 plántulas con diferentes concentraciones del filtrado, causando mortalidad en las primeras semanas. A partir de la semana 6, sólo un 32% resistieron el incremento de concentración. Para el décimo ciclo de inoculación, el 100% de plántulas permanecían en el filtrado crudo sin diluir, demostrando que a más tiempo en medio de crecimiento acelerado y mayor presión de selección, incrementando la concentración del filtrado, mayor probabilidad habrá de obtener variantes somaclonales con resistencia in vitro a Fusarium oxysporum.

Fusarium oxysporum Link is the cause of basal rotting in cardamom. The present article evaluates the phytotoxical effect of of the fungus crude filtrate, for selecting somaclonal variations of cardamom that showed resistance in greenhouse pathogenicity tests. According to mortality test results clone 5 and the isolated 4 were pointed with the most susceptibility-virulence interaction. From accelerated growth media seedlings there were selected 25 and inoculated with different concentrations of filtrate, causing mortality on the initial weeks. By the sixth week only a 32% resisted the concentration increment. By the tenth cycle of inoculation 100% of seedlings remained in the crude filtrate without dilutions. The more time the seedlings remain in accelerated growth media and the more selection pressure increasing filtrate concentration show increased probability of getting somaclonal variants with in vitro resistance of Fusarium oxysporum.

Hemodiálisis en tiempo de terremoto informe desde la Región del Biobío-Chile / Hemodialysis at earthquake time: a report from Biobio Region-Chile

El terremoto/tsunami grado 8,8 en la escala de Richter que afectó a nuestro país el 27 de febrero/2010, junto con provocar la pérdida de vidas humanas y cuantiosos daños materiales, dejó en evidencia la escasa preparación de la red de salud para enfrentar esta emergencia y especialmente lo relacionado con la terapia de diálisis. De los 1644 pacientes en hemodiálisis crónica en la Región del Bíobío, se registraron seis fallecidos (0,36 por ciento) en el período post catástrofe inmediato. Hubo pocos casos de rabdomiolisis por aplastamiento con insuficiencia renal aguda, y ninguno requirió apoyode diálisis. En el programa de peritoneo diálisis crónica ambulatoria no se reportaron casos de pacientes fallecidos. El presente informe reporta la situación de la terapia de diálisis y sus dificultades durante la catástrofe en la región, las acciones que contribuyeron a su rápida normalización y nuestras propuestas para elaborar en Chile un plan de diálisis en emergencias.

The 8.8ª Richter´s scale earthquake/tsunami which took placein Chile in February 27th, 2010, together with the loss of human lives and a large list of damaged materials, left evidence on the scarce preparation in the health public system to face this emergency and, especially, all which is related to hemodialysis therapy. Considering the 1644 patients in chronic dialysis in Bío-Bío Region, it was registered six deceases (0.36 percent) in the immediate post-catastrophe period. There were few cases of rhabdomyolysis, due to the flattening with acute renal deficiency and none of them required dialysis support. In the ambulatory chronic peritoneum dialysis program, deceases were not reported. The present report informs the situation of the dialysis therapy and its difficulties during the catastrophe in the region, the actions that contributed to its fast normalization and the proposals to make an emergency dialysis program in Chile.

Retinoic acid increases tissue and plasma contents of nerve growth factor and prevents neuropathy in diabetic mice.

BACKGROUND: Decreased production of nerve growth factor (NGF) may contribute to diabetic neuropathy; however, exogenous administration of NGF induces only a modest benefit. Retinoic acid (RA) promotes the endogenous expression of nerve growth factor and its receptor. We studied the effects of RA on diabetic neuropathy in mice with streptozotocin-induced diabetes. MATERIAL AND METHODS: One hundred and twenty National Institutes of Health (NIH) albino mice randomly separated into three groups (A, n = 30; B, n = 30; C, n = 60). Diabetes mellitus was induced with streptozotocin in groups A and B. Animals from group A received a subcutaneous injection of 25 microl of mineral oil daily for 90 days, while those from group B received a subcutaneous injection of 20 mg kg(-1) of all trans RA. Animals from group C were taken as controls. At the end of the experiment, blood glucose and NGF levels (both in serum and sciatic nerve) were measured. Two behavioural tests were conducted in a blind fashion to detect abnormalities of thermal and nociceptive thresholds. RESULTS: Contents of NGF in healthy untreated mice were 1490 +/- 190 pg mg(-1) in nerve and 113 +/- 67 pg mg(-1) in serum; in diabetic untreated mice the values were 697 +/- 219 pg mL(-1) in nerve and 55 +/- 41 pg mL(-1) in serum; and in diabetic mice treated with RA the values were 2432 +/- 80 pg mL(-1) in nerve and 235 +/- 133 pg mg(-1) in serum (P < 0.002). Ultrastructural evidence of nerve regeneration and sensitivity tests improved in diabetic mice treated with RA as compared with nontreated diabetic mice. CONCLUSION: Our findings indicate that administration of RA increases serum and nerve contents of NGF in diabetic mice and suggest a potential therapeutic role for retinoic acid in diabetic patients.

Frecuencia y características de las enfermedades más comunes, diagnosticadas por endoscopía alta en el Servicio de Medicina del hospital Hernán Henríquez Aravena de Temuco, 1998 - 2003 / Frequency and characteristics of the more common diseases diagnosed by upper endoscopy in hospital Hernán Henríquez Aravena of Temuco, medicine department, 1998-2003

En esta investigación se planteó la siguiente interrogante: ¿Cuál es la frecuencia y cuáles las características clínicas de las principales enfermedades diagnosticadas por endoscopía alta en la Unidad de Endoscopía del Hospital Hernán Henríquez Aravena de Temuco, Departamento de Medicina, durante los años 1998 al 2003? Los objetivos son conocer la frecuencia relativa de las principales enfermedades gastroenterológicas de diagnóstico endoscópico y sus características clínicas y sociodemográficas; medir sus cambios en el tiempo; aproximarse a una medición de la precisión del diagnóstico clínico y conocer la distribución real de las enfermedades que corresponden a los diagnósticos clínicos. Su diseño consistió en un corte transversal, en que se revisaron los diagnósticos clínicos retrospectivos e informes codificados de 6.016 endoscopías (1998- 2003). Para las enfermedades estudiadas, se calculó error alfa máximo de 0,05; confiabilidad mínima del 95 por ciento , y poder mínimo del 80 por ciento. Los resultados obtenidos son 36,6 por ciento de endoscopías normales; 13,9 por ciento esofagitis por reflujo; 7,6 por ciento gastropatías en todas sus variedades; úlcera duodenal 6,4 por ciento, úlcera gástrica 5,8 por ciento, várices esofágicas 5,7 por ciento; duodenitis 3,3 por ciento; cáncer gástrico 3 por ciento; esófago de Barrett 1,8 por ciento; candidiasis esofágica 1,5 por ciento; hernia hiatal 1,2 por ciento, pólipos gástricos 1,1 por ciento y no clasificable 4,6 por ciento. Las conclusiones son las siguientes: la esofagitis por reflujo es la enfermedad más común, seguida por la úlcera duodenal y la úlcera gástrica; en un alto porcentaje el estudio no se encuentra patología; las causas más frecuentes de hemorragia digestiva alta son las várices esofágicas y las úlceras pépticas; las enfermedades descritas muestran una tendencia cambiante en el tiempo, con aumento de la frecuencia de la esofagitis y la hemorragia digestiva elevándose y con disminución en el caso de las úlceras y el cáncer.

Coronavirus reverse genetics and development of vectors for gene expression.

Knowledge of coronavirus replication, transcription, and virus-host interaction has been recently improved by engineering of coronavirus infectious cDNAs. With the transmissible gastroenteritis virus (TGEV) genome the efficient (>40 microg per 106 cells) and stable (>20 passages) expression of the foreign genes has been shown. Knowledge of the transcription mechanism in coronaviruses has been significantly increased, making possible the fine regulation of foreign gene expression. A new family of vectors based on single coronavirus genomes, in which essential genes have been deleted, has emerged including replication-competent, propagation-deficient vectors. Vector biosafety is being increased by relocating the RNA packaging signal to the position previously occupied by deleted essential genes, to prevent the rescue of fully competent viruses that might arise from recombination events with wild-type field coronaviruses. The large cloning capacity of coronaviruses (>5 kb) and the possibility of engineering the tissue and species tropism to target expression to different organs and animal species, including humans, has increased the potential of coronaviruses as vectors for vaccine development and, possibly, gene therapy.

[Pediatric lung resection. A case series and evaluation of postoperative lung function]. / Resección pulmonar en pediatría. Serie clínica y evaluación de la función pulmonar postoperatoria.

The most common causes of pulmonary lobectomy in children are congenital lung malformations (CLM) and bronchiectasias. Our aim was to present the causes and clinical course and lung function of lobectomized patients. Between 1990 and July 1999 27 lobectomies were performed on patients whose ages ranged from newborn to 14 years. Lobectomies were performed to correct CLM in 124 cases and for acquired pulmonary disease (APD) in 13. Among CLM cases, half (n = 7) had cystic adenomatoid malformation. Among the APD patients, 10 had bronchiectasias, with etiological confirmation in 6 cases (3 secondary to serious adenovirus infection). Mean hospital stay was 4.6 days among those who experienced no postoperative complications. Symptoms resolved after surgery for most symptomatic patients. Lung function tests could be carried out with 8 patients over 6 years old whose operations had taken place 7 to 78 months earlier (x = 35 months) and whose age at the time of surgery was a mean 7 years 6 months (range 60 to 144 months). Spirometry showed normal forced vital capacity for 7 of 8 patients (87 to 143% of theoretical value). Arterial oxygen saturation measured during and after a 6-minute walking test was normal for 7 of 8 patients. Chest films showed reduced lung volume on the affected side in 5 of 8 patients. In summary, lobectomy is a procedure with few complications. It requires a short hospital stay and has good postoperative prognosis. Function and x-ray studies show adequate lung growth and development, with normal lung function in those who could be so examined because they were old enough to cooperate.

Resección pulmonar en pediatría. Serie clínica y evaluación de la función pulmonar postoperatoria / Pediatric lung resection. A case series and evaluation of postoperative lung function

Las causas más frecuentes de lobectomía pulmonar en niños son las malformaciones pulmonares congénitas (MPC) y las bronquiectasias. Nuestro objetivo es presentar la casuística y la evolución clínica y funcional respiratoria de pacientes lobectomizados. Entre 1990 y julio de 1999 se realizaron 27 lobectomías, entre recién nacidos y pacientes de 14 años. En 14 casos fue por MPC y en 13 por enfermedad pulmonar adquirida (EPA). Dentro de las MPC la mitad (n = 7) correspondieron a una malformación adenomatoidea quística. Del grupo de EPA 10 fueron bronquiectasias, con confirmación etiológica en 6 casos (3 secundarias a infección grave por adenovirus). De los pacientes que no presentaron complicación postoperatoria, el promedio de estancia hospitalaria fue de 4, 6 días. Las complicaciones fueron la aparición de filtración aérea en 3 casos, requiriendo sólo un tratamiento quirúrgico. En la mayoría de los pacientes sintomáticos hubo resolución de los síntomas posterior a la cirugía. Se logró realizar un estudio funcional respiratorio a 8 pacientes mayores de 6 años, cuya intervención quirúrgica se había realizado entre 7 y 78 meses previos (media de 35 meses) y cuya edad en el momento de la cirugía fue, como promedio de 7 años y 6 meses (rango: 60-144 meses). La espirometría demostró una capacidad vital forzada normal en 7 de 8 pacientes (87-143 por ciento del valor teórico). La medición de la saturación arterial de oxígeno durante y posterior a una caminata de 6 min fue normal en 7 de 8 pacientes. La radiografía de tórax demostró una disminución del volumen pulmonar en el lado intervenido en 5 de 8 pacientes. En resumen, la lobectomía es un procedimiento con escasas complicaciones, requiere un período corto de hospitalización y presenta un buen pronóstico postoperatorio. Los estudios funcional y radiológico demuestran un adecuado crecimiento y desarrollo pulmonar, con una evaluación de la función pulmonar normal en aquellos pacientes que se pudieron estudiar por tener una edad suficiente para poder colaborar en el examen (AU)

[Pleural effusion and complicated empyema in children. Evolution and prognostic factors]. / Derrame pleural y empiema complicado en niños. Evolución y factores pronósticos.

BACKGROUND: Complicated pleural empyema has a torpid and longer clinical evolution, requiring in some patients surgical management. The predictive factors for surgical treatment are not well known. AIM: To search for clinical, laboratory or radiological predictors for the requirement of surgical treatment in pediatric patients with empyema. PATIENTS AND METHODS: A retrospective review of the charts of 108 patients hospitalized for pneumonia plus pleural effusion at the Pediatric Service of the Catholic University Hospital between January 1985 and July 2000. RESULTS: Eighty one patients had complete radiological evaluation and pleural fluid biochemical analysis. Forty nine (60%) fulfilled the criteria for empyema and 32 (40%) for an exudate. Thirteen patients with empyema required surgery and 36 were treated medically. The mean age was 3 years (range 9 months-6 years) for the surgically treated and 4 years (range 12 months-14 years) for the non-surgical group. The male/female ratio was 5:1 in the surgical group and 1:1 for the non-surgical group. Pleural fluid cultures were positive in 21 of 79 patients. Streptococcus pneumonia was the most frequently isolated agent. No significant differences were found between groups for the average days of fever prior to the diagnosis or total days of fever, days of hospital stay, pleural fluid pH (6.8 and 7.0 respectively) and glucose (21 and 31 mg/dl respectively). No differences were either observed for pleural fluid risk factors (pH < 7 and glucose < 20 mgdl), the presence of extensive pleural effusions, pleural loculations or bands on pleural ultrasonography and positive Gram stain or cultures in the pleural fluid. Surgical patients required oxygen for more days than medical patients (7.7 and 5.1 days; p = 0.037). CONCLUSIONS: This study failed to find predictive clinical, radiological or pleural fluid parameters, for the requirement of surgical treatment of empyema.

[Medical-surgical experience of intestinal intussusception. Experience of a university institution]. / Enfrentamiento médico quirúrgico de la invaginación intestinal. Experiencia de una institución universitaria.

BACKGROUND: Management of intestinal intussusception in children has evolved from exclusively surgical treatments to nonoperative reduction under fluoroscopic monitoring. AIM: To report a 10 year experience in a University Hospital in the management of intestinal intussusception. PATIENTS AND METHODS: Seventy two patients, aged 2 to 72 months of age, with an uncomplicated intussusception, that were treated by barium or air enema, were studied. RESULTS: The success rate was 73% with barium reductions, and 100% with air reductions. In 17 patients (24%), enema reduction was unsuccessful and were subjected to a surgical reduction. CONCLUSIONS: Nonsurgical reduction is safe and effective as the initial treatment of uncomplicated intussusception in children.

[Vegetal foreign body in the airway: an unusual cause of hemoptysis in childhood. Clinical case]. / Cuerpo extraño vegetal en la vía aerea: una causa poco frecuente de hemoptisis en la niñez. Caso clínico.

Hemoptysis is an infrequent symptom in childhood and potentially life threatening. The most common causes in this age group are bronchiectasis secondary to cystic fibrosis, cardiovascular and pulmonary congenital anomalies and a miscellaneous group of causes including retained intrabronchial aspirated foreign bodies. We report a previously healthy 5-year-old girl with recurrent pneumonias associated with episodes of hemoptysis. She was admitted in our institution to investigate the persistence of hemoptysis. Based on clinical history, aspiration of a vegetal foreign body was postulated as the etiology and it was confirmed in the pathological examination after surgical exploration, with pulmonary lobe resection. The importance of a good history taking in pediatric hemoptysis is emphasized.

[Clinical experience in home care of children with tracheostomy]. / Experiencia clínica en el manejo domiciliario de niños traqueostomizados.

BACKGROUND: Home care of tracheostomized children is considered a safe and low-cost alternative. AIM: To report the experience with tracheostomized children at the Pediatric Respiratory Unit of the Catholic University Hospital. PATIENTS AND METHODS: The records of 16 children (9 male) with tracheostomy (TQ) in home care between 1992 and 1998 were reviewed. RESULTS: The average age at the moment of TQ was 9 months (range 1-30 months) and the postoperative hospital management period was 5 months (range 1-11 months). The average age at discharge was 13 months (range 3 to 30 months). Surgical indication were upper airway obstruction (congenital or acquired subglottic stenosis in three, upper airway malformations in one, vocal cord palsy in one and tracheobronchomalacia in one) and chronic assisted ventilation (severe tracheobronchomalacia in four, pulmonary hypoplasia in two, myopathy in one, central nervous injury in one and bronchopulmonary dysplasia in one). Overall rate complications were 2 per 100 tracheostomy months during home care and 8 per 100 tracheostomy months during hospital care. No tracheostomy-related deaths were observed. A parenteral education program to teach about tracheostomy management and cardiopulmonary resuscitation was carried out. CONCLUSIONS: Tracheostomized children can be safely managed at home.

Simple intratesticular cysts in children: preoperative sonographic diagnosis and histological correlation.

BACKGROUND: Simple intratesticular cysts are rare in children and have been considered the most uncommon cause of scrotal cystic masses in this age group. The exact etiology of these lesions is still unclear. High-resolution ultrasonography has been proved to be a reliable and accurate imaging modality in the evaluation of scrotal abnormalities in children. PATIENTS AND METHODS: We report the sonographic findings in five boys aged from 4 to 10 months who presented with a scrotal mass and had a simple intratesticular cyst. Ultrasonography showed that all of them displayed a characteristic appearance and provided the necessary information to perform conservative surgery, with testicular preservation in four infants. In one infant, the cyst involved most of the testis, and an orchiectomy was performed. RESULTS: Pathological examination revealed a single smooth-walled cystic structure, with clear and serous fluid, lined with flattened epithelial cells in all of the infants. CONCLUSION: Our findings appear to support the hypothesis that these cysts could correspond to mesothelial inclusions. Sonographically, differential diagnosis should include mainly epidermoid cysts of the testis, which are mostly cystic but characteristically contain some echoes within them, in contrast to simple cysts and cysts of the tunica albuginea, which lie outside the testicular parenchyma.