Resumen Introducción: La tuberculosis peritoneal (tuberculosis abdominal) puede ser confundida con una neoplasia maligna. Objetivo: Describir características clínicas y demográficas de pacientes con tuberculosis abdominal que semeja cáncer de ovario avanzado, diagnosticados en un centro oncológico de referencia nacional. Métodos: Se describen las características clínicas y patológicas de nueve pacientes con tuberculosis abdominal que clínicamente semejaba cáncer de ovario avanzado Resultados: La mediana de edad fue de 47 años, el estrato socioeconómico más común fue bajo (44 %). El dolor abdominal y la pérdida ponderal se presentaron en 77.7 %, ascitis en 55.5 %, prueba COMBE positiva en 22.2 % y ausencia de antecedente de tuberculosis pulmonar en 100 %. La elevación de CA-125 se reportó en 77.7 %, con > 500 U/mL en 57.1 %. La tomografía indicó carcinomatosis en 50 % y tumor pélvico y ascitis en 37.5 %. Todas las pacientes fueron sometidas a cirugía; 62.5 % fueron diagnosticadas mediante estudio patológico transoperatorio como enfermedad neoplásica Conclusión: La tuberculosis es considerada como la gran imitadora, por ello se debe tener en mente el diagnóstico de tuberculosis abdominal ante un caso sospechoso, aun cuando la presentación clínica, estudios de imagen e, incluso, el examen transoperatorio sugieran cáncer de ovario.

Abstract Introduction: Peritoneal tuberculosis (abdominal tuberculosis) can be confused with a malignant neoplasm. Objective: To describe clinical and demographic characteristics of patients with abdominal tuberculosis mimicking advanced ovarian cancer, diagnosed in a national reference cancer center. Methods: Clinical and pathological characteristics of nine patients with abdominal tuberculosis that clinically resembled advanced ovarian cancer are described. Results: Median age was 47 years; the most common socioeconomic status was low (44%). Abdominal pain and weight loss occurred in 77.7%; ascites, in 55.5%; 22.2% had a positive COMBE test, and 100% had no history of pulmonary tuberculosis. CA-125 elevation was reported in 77.7%, with levels > 500 U/mL in 57.1%. Tomography reported carcinomatosis in 50% and pelvic tumor and ascites in 37.5%. All patients underwent surgery, where 62.5% were diagnosed by intraoperative pathology study as neoplastic disease. Conclusion: Tuberculosis is considered the great imitator, which is why abdominal tuberculosis diagnosis should be borne in mind when faced with a suspicious case, even when clinical presentation, imaging studies, and even intraoperative examination suggest ovarian cancer.

Abstract Introduction: Even with an adequate mechanical ventilation weaning (MVW) protocol, the procedure fails in 15 to 30 % of cases. Objective: To assess the association between independent risk factors (IRFs) and post-extubation failure in patients undergoing MVW in an intensive care unit. Method: Longitudinal, prospective, analytical cohort study in patients on mechanical ventilation for more than 24 hours and who were extubated. Pre-extubation reports of hemoglobin, albumin, phosphorus, waist-hip ratio and SOFA score were obtained. Extubation failure was defined as resumption of mechanical ventilation within 48 hours or less. Results: 123 patients were extubated, out of whom 74 were males (60 %); average age was 50 ± 18 years. Extubation failure occurred in 37 (30 %). Hypoalbuminemia was associated as an independent risk factor in 29 (23.8 %, RR = 1.43, 95 % CI = 1.11-1.85) and hypophosphatemia was in 18 (14.6 %, RR = 2.98, 95 % CI = 1.66-5.35); two or more IRFs were observed in 22.7 % (RR = 1.51, 95 % CI = 1.14-2.00). Conclusions: Identifying independent risk factors prior to MVW can help reduce the risk of extubation failure and associated morbidity and mortality.

Resumen Introducción: Aun con adecuado protocolo de desconexión de la ventilación mecánica (DVM), el procedimiento falla en 15 a 30 % de los casos. Objetivo: Evaluar la asociación entre factores de riesgo independientes y fracaso posextubación en pacientes con DVM en una unidad de cuidados intensivos. Método: Estudio de cohorte, longitudinal, prospectivo, analítico, que incluyó pacientes sometidos a ventilación mecánica por más de 24 horas y que fueron extubados. Se obtuvieron reportes preextubación de hemoglobina, albúmina, fósforo, índice cintura-cadera y puntuación SOFA. Se definió como fracaso de extubación al reinicio de la ventilación mecánica en 48 horas o menos. Resultados: Se extubaron 123 pacientes, 74 hombres (60 %); la edad promedio fue de 50 ± 18 años. Ocurrió fracaso de extubación en 37 (30 %). Como factores de riesgo independentes se asoció hipoalbuminemia en 29 (23.8 %, RR = 1.43, IC 95 % = 1.11-1.85) e hipofosfatemia en 18 (14.6 %, RR = 2.98, IC 95 % = 1.66-5.35); se observaron dos o más factores de riesgo independientes en 22.7 % (RR = 1.51, IC 95 % = 1.14-2.00). Conclusiones: Identificar los factores de riesgo independentes antes de la DVM puede ayudar a reducir el fracaso de la extubación y la morbimortalidad asociada.

In this work, the capability to use pine rosin as a biodegradable coupling agent/compatibilizer is studied. To formulate composites, post-consumer polypropylene and discarded agave fibers (as reinforcing agent) are coupled with pine rosin (in pure or maleated form). Besides, poly(lactic acid) (PLA) with poly(butylene adipate-co-terephthalate) (PBAT) are compatibilized with maleated pine rosins to prepare biodegradable blends. For the coupling agent role, the pure or maleated rosin (Amberyl M-15A) are compared with a commercial polyolefin coupling agent (Epolene E-43), while for the blends, two maleated rosins (Amberyls M-15A and MP-30) are used as compatibilizers. Dynamic and static mechanical tests show considerable increments in moduli and strength for both types of polymeric materials surpassing the role of the Epolene E-43 for the composite materials (v.g. 45.2 vs 16.5 increment in storage modulus, or 61.5 vs 40.3 for Young’s modulus in specific tests). Scanning electron microscopy photographs clearly show the interfacial interaction effect within composites and polymer blends. Fourier transform infrared spectroscopy allowed the observation of the aforementioned interactions at bond level. Blends biodegradation performed by composting for 3 months exceeded 76% of weight loss. The multirole of modified natural maleated gums as coupling agents/compatibilizers is demonstrated.

The synthesis of polyacrylamide-cellulose acetate hydrogels by precipitation polymerization in acetone solution is reported herein. These hydrogels exhibit smaller swelling ratios and larger compression moduli than homo polyacrylamide hydrogels. For cellulose acetate concentrations above 20 wt.%, hydrogels with N,N'-methylenebisacrylamide as a crosslinker exhibit swelling ratios and compression moduli similar to those of the hydrogels without the crosslinker. A possible explanation for this behavior is that cellulose acetate crosslinks polyacrylamide via free-radical reaction. The hydrogels obtained without the N,N'-methylenebisacrylamide crosslinker exhibit compression moduli up to 1.7 MPa, making them suitable for tissue engineering applications such as cartilage replacement.

Embora a doença de Alzheimer seja um distúrbio do cérebro, uma série de alterações periféricas têm sido encontradas nesses pacientes; no entanto, pouco se sabe sobre como os genes envolvidos na fisiopatologia se expressam nas células periféricas, tais como em linfócitos durante o envelhecimento normal em comparação com o neuropatológico. Analisamos por RT-PCR a expressão dos genes de tau, da proteína precursora do amilóide, de nicastrin e da enzima de clivagem do sítio β da APP, em linfócitos de um pequeno grupo de pacientes com início tardio da Doença de Alzheimer, de um grupo de pacientes idosos que sofrem de doenças neuropsicológicas diferentes de Alzheimer, e de um grupo de indivíduos cognitivamente saudáveis, divididos em quatro grupos por idade. Também foram investigadas as correlações entre a expressão dos genes e os níveis de pressão arterial, glicose, colesterol total e triglicérides, como fatores de risco para doença de Alzheimer. Os resultados mostram a ausência de expressão de tau em linfócitos, a ausência de detecção da expressão do gene de nicastrina em pacientes com Alzheimer, e a correlação entre as condições médicas estudadas e a expressão gênica nos linfócitos. Acreditamos que a expressão de nicastrin em linfócitos deve ser considerada de interesse para análises em uma população mais ampla, para investigar se ela pode representar um potencial biomarcador para diferenciar a doença de Alzheimer de outros distúrbios neuropsicológicos.

Although Alzheimer's disease is a brain disorder, a number of peripheral alterations have been found in these patients; however, little is known about how the key genes involved in the pathophysiology express in peripheral cells such as lymphocytes during normal compared to neuropathological ageing. We analysed the expression of tau, of the amyloid precursor protein, of nicastrin and of the β-site APP cleaving enzyme genes by RT-PCR in lymphocytes from a small group of late-onset Alzheimer's disease patients, from aged patients suffering from neuropsychological conditions different from Alzheimer's and from cognitively healthy subjects divided in four groups by age. We also investigated correlations between gene expression and levels of blood pressure, glucose, total cholesterol and triglycerides as risk factors for Alzheimer's. Results show no tau expression in lymphocytes, a lack of detection of nicastrin expression in Alzheimer's patients and correlations between the medical conditions studied and gene expression in lymphocytes. We believe nicastrin gene expression in lymphocytes should be considered of interest for further analyses in a wider population to investigate whether it might represent a potential biomarker to differentiate Alzheimer's from other neuropsychological disorders.

The capillary electrophoresis technique associated with the SQUAD computer program has been used to study the interaction between humic acid and heavy metals (Cu2+, Pb2+, Hg2+, Co2+, Cd2+). Such interaction causes a shift in the migration time of metals depending on the concentration of humic acid. From this information the effective electrophoretic mobility was determined and then introduced to the SQUAD program to calculate the equilibrium constants considering a 1:1 stoichiometry. The affinity of humic acid to the metals decreases in the following order: Cu2+>Pb2+>Hg2+>Co2+>Cd2+. The respective equilibrium constants (log b1) are: 3.48±0.33, 3.62±0.24, 3.18±0.19, 2.96±0.20 and 2.58±0.33. This tendency is consistent with the Pearson HSAB theory and with other data published in the literature.

La técnica de electroforesis capilar asociada con el programa computacional SQUAD ha sido empleada para el estudio de la interacción entre metales pesados (Cu2+, Pb2+, Hg2+, Co2+, Cd2+) y un ácido húmico. Dicha interacción, provoca el desplazamiento en el tiempo de migración de los metales en función de la concentración del ácido. De esta información es posible obtener las movilidades electroforéticas efectivas y alimentarlas al programa SQUAD para calcular las constantes de equilibrio considerando una estequiometría 1:1. La afinidad del ácido húmico hacia los metales decrece en el siguiente orden: Cu2+>Pb2+>Hg2+>Co2+>Cd2+. Las respectivas constantes de equilibrio son: (log b1): 3.48±0.33, 3.62±0.24, 3.18±0.19, 2.96±0.20 y 2.58±0.33. Esta tendencia coincide con la teoría ABDB de Pearson y con otros datos de la literatura.

From July to December 1998, 41 children with digestive disorders, who had been seen at the Service of Gastroenterology were studied. Their digestive disorders were characterized by abdominal pain, nausea, pyroxis, vomit, hematoemesis and melena. All patients were evaluated by gastroduodenoscopy and 2 samples of the gastric antrum mucous were selected for a histologic study and diagnosis of Helicobacter pylori through Gram ´s stain and urease test. Data were mechanically compared and for determining association among variables, a non-parametric Chi square test was used, with an accuracy of 95% where P0.05. Twenty five patients were diagnosed with H. Pylory accounting for 61% whereas the most affected was the 10-15 y age group. Recurrent abdominal pain was found in all H. Pylori-positive patients and 96% had antral gastritis. The most frequent form was chronic inactive surface gastritis. There was 88% coincidence between the urease test and Grams stain

En el período comprendido de julio a diciembre de 1998, se estudiaron 41 niños que acudieron al Servicio de Gastroenterología con trastornos digestivos dados por: dolor abdominal, náuseas, pirosis, vómitos, hematemesis y melena. A todos se les realizó gastroduodenoscopia, y se seleccionaron 2 muestras de la mucosa del antro gástrico para estudio histológico y diagnóstico de Helicobacter pylori mediante coloración de Gram y prueba de la ureasa. Los datos se confrontaron de forma mecánica y para la asociación entre variables se utilizó la técnica no paramétrica de chi cuadrado con una precisión del 95 %, donde p < 0,05. Se diagnosticó en 25 pacientes H. pylori para el 61 % y el grupo etáreo más afectado fue el de 10 a 15 años. El dolor abdominal recurrente estuvo presente en el 100 % de los pacientes positivos por H. pylori y el 96 % tenía gastritis antral, y fue más frecuente la gastritis crónica superficial inactiva. Se verificó concordancia del 88 % entre la prueba de la ureasa y la coloración de Gram en el diagnóstico.