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1. The purpose of this work was to support decision-making in poultry farms by performing automatic early detection of anomalies in egg production. 2. Unprocessed data were collected from a commercial egg farm on a daily basis over 7 years. Records from a total of 24 flocks, each with approximately 20 000 laying hens, were studied. 3. Other similar works have required a prior feature extraction by a poultry expert, and this method is dependent on time and expert knowledge. 4. The present approach reduces the dependency on time and expert knowledge because of the automatic selection of relevant features and the use of artificial neural networks capable of cost-sensitive learning. 5. The optimum configuration of features and parameters in the proposed model was evaluated on unseen test data obtained by a repeated cross-validation technique. 6. The accuracy, sensitivity, specificity and positive predictive value are presented and discussed at 5 forecasting intervals. The accuracy of the proposed model was 0.9896 for the day before a problem occurs.

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This work shows the results obtained on a copper mine tailing in the Antofagasta Region, Chile. The tailing was classified as saline-sodic with high concentrations of metals, especially Cu and Fe, with pH 8.4. Our objectives were to (1) compare the physicochemical properties of the tailing with surrounding soils of the mine under study, and (2) evaluate the effect of two amendments (CaCO3 and compost) and their mixtures on Cu(2+), Mn, Fe, Zn, Mg(2+), and K(+) and Ca(2+), SO4 (2-), NO3 (-), and PO4 (3-) leaching. The data obtained were submitted to variance and covariance analysis. The results from the comparison between both substrates showed that in general, the tailing presented greater content of metals. Regarding tailing leaching, pH, electrical conductivity (EC), and concentration of the elements of interest were measured. The statistical analysis showed that Cu(2+) leaching and immobilization of Fe occurred to the greatest extent with compost. The EC decreased throughout the experiment with irrigation and increased upon treatment with compost. The major interactions found among the chemical parameters were (1) tailings without treatment, Cu(2+)/Fe and NO3 (-)/SO4 (2-); (2) tailings treated with CaCO3, Cu(2+)/K(+); (3) tailings treated with compost, NO3 (-)/SO4 (-2) and EC/Cu(2+); and (4) tailings treated with both amendments, EC/Fe and Cu(2+)/Fe. The ANOVA showed that the number of irrigations and the amendments statistically significantly affected the copper mobility and the organic amendment significantly influenced the iron mobility.

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Las Vasculitis Primarias son enfermedades poco frecuentes, potencialmente fatales, sin causa etiológica conocida, que pueden comprometer a vasos sanguíneos de distinto tamaño, produciéndoles un proceso inflamatorio en la pared vascular, que conduce a la estrechez u obstrucción del vaso afectado, con consecuente isquemia o necrosis del tejido que irrigan. Sus manifestaciones clínicas pueden ser muy variadas, y frecuentemente inespecíficas. Sin embargo hay algunas que hacen sospechar el diagnóstico y que deben ser evaluadas con detalle. El estudio diagnóstico de las vasculitis primarias, implica varios aspectos que deben ser considerados. La actividad, la extensión, el daño visceral y el diagnóstico diferencial. En este sentido los exámenes bioquímicos; los exámenes funcionales organicos; los estudios de imágenes (radiológicos, tomografía computarizadas, resonancia magnética, radio isotópicas, y de Pet -CT); y la histopatología (biopsias de riñón, sistema nervioso periférico, pulmonar, etc.); y los estudios de autoanticuerpos (muy especialmente los ANCA, en vasculitis de pequeño vaso) ayudan a fundamentar el diagnóstico definitivo. Su tratamiento debe considerar dos etapas. Inicialmente la terapia de inducción de la remisión, y luego de lograrla, la de mantenimiento de la remisión. De la naturaleza de la vasculitis y del éxito que se logre con el tratamiento, dependerá su pronóstico. Las drogas tradicionales, más usadas en el tratamiento, y habitualmente más efectivas, son los corticoesteroides (orales o EV en bolos) y la ciclofosfamida (oral o preferentemente en bolos EV). Tambien se han usado la Azatioprina, el metotrexato, y el micofenolato mofetil, especialmente como mantenimiento de remisión. En los últimos años, se ha destacado el uso de terapia biológica, con anticuerpos monoclonales anti lifocitos B, el Rituximab, que resulta de gran utilidad, muy especialmente en las vasculitis de pequeño vaso ANCA positivo. El diagnóstico diferencial incluye patologías muy diversas; trombosis ateroesclerótica; embolias ateroescleróticas, embolias sépticas, el uso de drogas ilícitas, y la trombosis secundaria al Sindrome Antifosfolípido.

Primary vasculitis is an infrecuent desease, and may present in very different clinical pictures. Any size of blood vessels can be affected (aorta, large it; arteries, médium -size, and small), it may be produced by immunological tissue damage mechanisms. Classification of primary vasculitis usually consider both aspects. Histopathology includes, giant cells large vasculitis; granulomatous aortitis; systemic inflamatory necrotizing and segmentary médium size arterities; Granomalous necrotazing small vessel vasculitis, with or without eosinofilic infiltration; and leucocitoclastic small vessel vasculitis. Clinicians should be awared of this deseases in order to diagnose promptly and do a proper therapy.

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Chronic obstructive pulmonary disease (COPD) is associated with inflammatory cell reactions, tissue destruction and lung remodeling. Many signaling pathways for these phenomena are still to be identified. We developed a mouse model of COPD to evaluate some pathophysiological mechanisms acting during the initial stage of the disease. Forty-seven 6- to 8-week-old female C57/BL6 mice (approximately 22 g) were exposed for 2 months to cigarette smoke and/or residual oil fly ash (ROFA), a concentrate of air pollution. We measured lung mechanics, airspace enlargement, airway wall thickness, epithelial cell profile, elastic and collagen fiber deposition, and by immunohistochemistry transforming growth factor-β1 (TGF-β1), macrophage elastase (MMP12), neutrophils and macrophages. We observed regional airspace enlargements near terminal bronchioles associated with the exposure to smoke or ROFA. There were also increases in airway resistance and thickening of airway walls in animals exposed to smoke. In the epithelium, we noted a decrease in the ciliated cell area of animals exposed to smoke and an increase in the total cell area associated with exposure to both smoke and ROFA. There was also an increase in the expression of TGF-β1 both in the airways and parenchyma of animals exposed to smoke. However, we could not detect inflammatory cell recruitment, increases in MMP12 or elastic and collagen fiber deposition. After 2 months of exposure to cigarette smoke and/or ROFA, mice developed regional airspace enlargements and airway epithelium remodeling, although no inflammation or increases in fiber deposition were detected. Some of these phenomena may have been mediated by TGF-β1.

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Chronic obstructive pulmonary disease (COPD) is associated with inflammatory cell reactions, tissue destruction and lung remodeling. Many signaling pathways for these phenomena are still to be identified. We developed a mouse model of COPD to evaluate some pathophysiological mechanisms acting during the initial stage of the disease. Forty-seven 6- to 8-week-old female C57/BL6 mice (approximately 22 g) were exposed for 2 months to cigarette smoke and/or residual oil fly ash (ROFA), a concentrate of air pollution. We measured lung mechanics, airspace enlargement, airway wall thickness, epithelial cell profile, elastic and collagen fiber deposition, and by immunohistochemistry transforming growth factor-ß1 (TGF-ß1), macrophage elastase (MMP12), neutrophils and macrophages. We observed regional airspace enlargements near terminal bronchioles associated with the exposure to smoke or ROFA. There were also increases in airway resistance and thickening of airway walls in animals exposed to smoke. In the epithelium, we noted a decrease in the ciliated cell area of animals exposed to smoke and an increase in the total cell area associated with exposure to both smoke and ROFA. There was also an increase in the expression of TGF-ß1 both in the airways and parenchyma of animals exposed to smoke. However, we could not detect inflammatory cell recruitment, increases in MMP12 or elastic and collagen fiber deposition. After 2 months of exposure to cigarette smoke and/or ROFA, mice developed regional airspace enlargements and airway epithelium remodeling, although no inflammation or increases in fiber deposition were detected. Some of these phenomena may have been mediated by TGF-ß1.

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The mechanisms by which PM(2.5) increases cardiovascular mortality are not fully identified. Autonomic alterations are the current main hypotheses. Our objective was to determine if PM(2.5) induces acute cardiac polarization alterations in healthy Wistar rats. PM(2.5) samples were collected on polycarbonate filters. Solutions containing 10, 20, and 50 microg PM(2.5) were administered by tracheal instillation. P wave duration decreased significantly at 20 microg (0.99 +/- 0.06, 0.95 +/- 0.06, and 0.96 +/- 0.07; P < 0.001), and 50 microg (0.98 +/- 0.06, 0.98 +/- 0.07, and 0.96 +/- 0.08; 60, 90 and 120 min, respectively) compared to blank filter solution (P < 0.001). PR interval duration decreased significantly at 20 microg (0.99 +/- 0.06, 0.98 +/- 0.07, and 0.97 +/- 0.08) and 50 microg (0.99 +/- 0.05, 0.97 +/- 0.0, and 0.95 +/- 0.05; 60, 90, and 120 min, respectively) compared to blank filter and 10 microg (P < 0.001). QRS interval duration decreased at 20 and 50 microg in relation to blank filter solution and 10 microg (P < 0.001). QT interval duration decreased significantly (P < 0.001) with time in animals receiving 20 microg (0.94 +/- 0.12, 0.88 +/- 0.14, and 0.88 +/- 0.11) and 50 microg (1.00 +/- 0.13; 0.97 +/- 0.11 and 0.98 +/- 0.16; 60, 90 and 120 min, respectively) compared to blank filter solution and 10 microg (P < 0.001). PM(2.5) induced reduced cardiac conduction time, within a short period, indicating that depolarization occurs more rapidly across ventricular tissue.

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The mechanisms by which PM2.5 increases cardiovascular mortality are not fully identified. Autonomic alterations are the current main hypotheses. Our objective was to determine if PM2.5 induces acute cardiac polarization alterations in healthy Wistar rats. PM2.5 samples were collected on polycarbonate filters. Solutions containing 10, 20, and 50 µg PM2.5 were administered by tracheal instillation. P wave duration decreased significantly at 20 µg (0.99 ± 0.06, 0.95 ± 0.06, and 0.96 ± 0.07; P < 0.001), and 50 µg (0.98 ± 0.06, 0.98 ± 0.07, and 0.96 ± 0.08; 60, 90 and 120 min, respectively) compared to blank filter solution (P < 0.001). PR interval duration decreased significantly at 20 µg (0.99 ± 0.06, 0.98 ± 0.07, and 0.97 ± 0.08) and 50 µg (0.99 ± 0.05, 0.97 ± 0.0, and 0.95 ± 0.05; 60, 90, and 120 min, respectively) compared to blank filter and 10 µg (P < 0.001). QRS interval duration decreased at 20 and 50 µg in relation to blank filter solution and 10 µg (P < 0.001). QT interval duration decreased significantly (P < 0.001) with time in animals receiving 20 µg (0.94 ± 0.12, 0.88 ± 0.14, and 0.88 ± 0.11) and 50 µg (1.00 ± 0.13; 0.97 ± 0.11 and 0.98 ± 0.16; 60, 90 and 120 min, respectively) compared to blank filter solution and 10 µg (P < 0.001). PM2.5 induced reduced cardiac conduction time, within a short period, indicating that depolarization occurs more rapidly across ventricular tissue.

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Several epidemiological studies have consistently demonstrated significant associations between ambient levels of particulate matter and lung injury and cardiovascular events with increased morbidity and mortality. Particle surrogates (PS), such as residual oil fly ash (ROFA), have been widely used in experimental studies aimed at characterizing the mechanisms of particle toxicity. Since PS composition varies depending on its source, studies with different types of PS may provide clues about the relative toxicity of the components generated by high-temperature combustion process. In this work, we have studied the effects of nasal instillation of increasing doses of different PS in mice: saline, carbon, and two types of particle surrogates. PS type A (PSA) was the ROFA collected from the waste incinerator of our university hospital; PS type B (PSB) was collected from the electrostatic precipitator of a large steel company and thus had an elevated metal content. After 24h, we analyzed hematological parameters, fibrinogen, bronchoalveolar lavage, bone marrow, and pulmonary histology. Nasal instillation of the two types of PS-induced leucopenia. PSB elicited a greater elevation of plasma fibrinogen levels. Bone marrow and pulmonary inflammatory changes were more intense for PSA. We concluded that the PS composition modulates acute inflammatory changes more significantly than the mass for these two types of PS.

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In this study, we explored the role of chronic exposure to urban air pollution in causing DNA damage (micronuclei frequency in peripheral erythrocytes) in rodents in vivo. Mice (n=20) were exposed to the urban atmosphere of São Paulo for 120 days (February to June 1999) and compared to animals (n=20) maintained in the countryside (Atibaia) for the same period. Daily levels of inhalable particles (PM10), CO, NO(2), and SO(2), were available for São Paulo. Occasional measurements of CO and O(3) were made in Atibaia, showing negligible levels of pollution in the area. The frequency of micronuclei (repeated-measures ANOVA) increased with aging, the highest values obtained for the 90th day of experiment (P<0.001). The exposure to urban air pollution elicited a significant (P=0.016) increase of micronuclei frequency, with no significant interaction with time of study. Associations (Spearman's correlation) between pollution levels of the week that precede blood sampling and micronuclei counts were observed in São Paulo. The associations between micronuclei counts and air pollution were particularly strong for pollutants associated with automotive emissions, such as CO (P=0.037), NO(2) (P<0.001), and PM10 (P<0.001). Our results support the concept that urban levels of air pollution may cause somatic mutations.

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Cambios a largo plazo en la actividad del complejo piruvato deshidrogenasa (PDC) hepático en respuesta a distintas dietas modifican la cantidad de enzima presente. En este trabajo se determinaron los niveles de mRNA correspondientes a la subunidad E1 del complejo mediante RT-PCR semicuantitativo. Se determinó que la dieta rica en sacarosa produjo un incremento de 40 por ciento en los niveles de mRNA correspondiente a la subunidad E1 con respecto a los animales control luego de 7 días. Al cabo de 14 a 21 días, el incremento fue de sólo 20 por ciento. La adición de aceite de pescado a las dietas redujo los niveles de mRNA a niveles indistinguibles del control en sólo 7 días. La regulación de la expresión del gene para E1 puede atribuirse a modificaciones en las tasas de transcripción genética o en la estabilidad del mensajero transcrito, en forma similar a las enzimas que regulan la lipogénesis

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STUDY OBJECTIVES: The mechanisms involved in the impairment of mucociliary function after lung transplantation are not completely understood. The purpose of the present study was to isolate the effects of unilateral bronchial transection and reanastomosis in a rat model. DESIGN: In situ bronchial mucociliary transport (MCT) was determined proximal and distal to the bronchial anastomosis, as well as in the right bronchus, in 48 rats classified into six groups: intact rats, and rats at 1 day, 2 days, 7 days, 15 days, and 30 days after bronchial transection and reanastomosis of the left main stem bronchus. In vitro mucus transportability and mucus contact angle were studied in another group of eight rats after 1 week of surgery. RESULTS: Distal to the anastomosis site, left bronchus in situ MCT (mean +/- SD) was 0.26 +/- 0.19 mm/min for the intact group, and 0.11 +/- 0.13 mm/min, 0.07 +/- 0.04 mm/min, 0.03 +/- 0.04 mm/min, 0.07 +/- 0.12 mm/min, and 0.05 +/- 0.06 mm/min for 1 day, 2 days, 7 days, 15 days, and 30 days after surgery, respectively (all significantly reduced, p < 0.05). No intergroup differences were found proximal to the anastomosis (p = 0.30). When comparing the left and right bronchi, differences were detected in both distal (p < 0.0001) and proximal sides (p = 0.0001). No significant differences in mucus transportability in vitro were found (p = 0.15). Mucus contact angle of the left bronchus (52.8 +/- 20.5 degrees ) was significantly greater than that of the mucus from the right bronchus (34.4 +/- 12.9 degrees; p < 0.05). CONCLUSIONS: We conclude that bronchial transection and reanastomosis lead to a marked impairment of MCT in distal airways, which can in part be explained by alterations in the surface properties of mucus.

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Cyclosporine may be useful in the treatment of rheumatoid arthritis refractory to other immunosupressive agents, in doses of less than 10 mg/kg/day to minimize its nephrotoxic potential, that is enhanced with prolonged use of concomitant administration of antiinflammatory drugs. We report 15 patients aged 50 ñ 12 years with erosive rheumatoid arthritis lasting 5 ñ 4 yeras and refractory to other immunosupressive agents. They were studied during one year and received cyclosporine in initial doses of 2.5 mg/kg/day that were increased to 5 mg/kg/day, assessing clinical response, blood pressure and serum creatinine. Nine patients, that received a maximal dose of 3.4 ñ 0.7 mg/kg/day during 7 ñ 4 months, improved; a 30 percent increase in creatinine was observed in 3, blood pressure raised in six and 2 bad hepatic toxicity. in the 6 patients that did not improve, the mean treatment lapse was 4 ñ 3 months and the maximal dose achieved was 2.7 mg/kg/day; creatinine increased in one and blood pressure increased in 4. It is concluded that although the clinical response to cyclosporine was good, only 4 patients completed one year of treatment, due to the frequent secondary effects of the drug

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To define better the epidemiology and clinical impact of hepatitis delta virus (HDV) infection among hepatitis B virus (HBV) carriers in less developed countries, the authors prospectively studied a cohort of 216 Yucpa Indian HBV carriers in Venezuela. HBV carriers were followed regularly between 1983 and 1988 by physical examination, laboratory testing for liver enzymes and HBV and HDV markers, and epidemiologic history. Among the cohort, 74 (34%) were initially positive for HDV infection, and 35 additional persons became infected during the study. Risk factors for new HDV infection included living in southern Yucpa villages; being young adults (15-19 years) or young children (1-9 years), and living in a household with a person with acute HDV infection. Persons with HDV infection were at high risk of developing chronic liver disease; 56% of HDV-infected persons had moderate-to-severe chronic liver disease at the end of the study compared with none of the HBV carriers without HDV infection. Mortality rates were 6.9% and 8.8% per year, respectively, among initially HDV-positive HBV carriers and those with new HDV infection, because of rapidly progressive chronic liver disease and fulminant hepatitis; mortality was significantly lower in HBV carriers without HDV infection and in non-HBV carriers. HDV superinfection is a devastating disease in HBV carriers in tropical South America. Prevention of HBV infection with hepatitis B vaccine is the best available tool to reduce the impact of this problem.

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A cost-benefit study for hepatitis B vaccination in Venezuelan hospital workers was performed through a decision tree analysis model, which includes the probabilities for the different outcomes of the hepatitis B virus infection (HBV). The current average cost of HBV infection to the Venezuelan Government was estimated at US$ 1,759 per patient. Implementation of selective vaccination or a mass vaccination campaign for the hospital workers would reduce the total cost of HBV infection to 51% or 28%, respectively, saving $17 to $26 million. This type of economic analysis may influence the distribution of the resources to be allocated for the control of HBV infection in Venezuela.

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Se estudiaron cinco pacientes con cáncer de la vesícula biliar (CV) con prolongada sobrevida postoperatoria (4-12 años): Grupo A. Se compara este grupo con cinco pacientes intervenidos recientemente, cuya enfermedad está avanzada: Grupo B y con cinco enfermos sometidos a colecistectomía por litiasis y sin cáncer: Grupo C (control). En el Grupo A hubo 2 casos con antecedentes de cáncer en otras localizaciones (mama, útero y recto), lo que hace suponer una predisposición neoplásica y una especial inmunidad contra el cáncer. En este estudio preliminar, la respuesta inmunitaria de los pacientes del Grupo A y C fue similar. En los enfermos del Grupo B, se observó reducción de la inmunocompetencia con la progresión de la enfermedad, especialmente en los test cutáneos. En el estudio histoquímico, en los Grupos A y B, las poblaciones celulares relacionadas con la inmunidad se situaron en la periferia del tumor pero sólo en las del Grupo A se encontraron en el interior de la masa tumoral. En la investigación inmunogénetica se observó que el antígeno HLA-DR4 se encuentra en una proporción mayor en los pacientes con CV (38%), en comparación con la población chilena nornal (29%). Se incluye que es necesario: a. Proseguir la investigación, aumentando el número de casos; b. trabajar en el estudio inmuno histoquímico sólo con vesículas frescas, y c. Seguir investigando los antígenos del sistema HLA, tanto en pacientes portadores de cáncer vesícular, como en aquéllos con simple colelitiasis

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Se estudiaron 322 lactantes sanos, eutróficos, entre 3 y 18 meses de edad, que habían sido inmunizados con BCG en el período neonatal y procedían de salas-cunas de la Región Metropolitana. Entre ellos, 304 (92,4%) tenían cicatriz BCG y fueron ingresados a un estudio doble ciego aleatorio, para determinar eventuales variaciones en las respuestas cutáneas a PPD 2 UT y 10 UT. No se encontraron diferencias en el tamaño de las respuestas cutáneas ni el porcentaje de respuestas positivas (* 10 mm), excepto para las reacciones * 15 mm, que fueron más frecuentes en los niños inoculados con PPD 10 UT. En 184/304 (60,5%) se obtuvo respuesta cutánea negativa (* 10 mm). Los 18/322 (5,6%) que no tenían cicatriz BCG fueron inoculados con PPD 2 UT: ninguno mostró respuesta cutánea positiva y en 3/18 ésta fue de 6 a 9 mm. Al administrar una segunda dosis de PPD a 55 lactantes cuya respuesta inicial había sido * 5 mm, se obtuvieron reacciones de mayor tamaño que en la primera en los niños que tenían cicatriz BCG cuando la segunda dosis era igual o mayor potencia que la primera, sugiriendo un mecanismo de refuerzo

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Los corticoesteroides constituyen en la actualidad el medicamento antiinflamatorio más poderoso, cuya utilidad puede verse limitada por los numerosos efectos indeseables que su uso puede traer consigo, especialmente cuando su administración es prolongada

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