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1.
Foods ; 12(21)2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37959117

RESUMEN

This paper reports the development of a near-infrared spectroscopy (NIRS) calibration procedure for the determination of sodium and potassium content in cured ham samples. Sliced samples of hams treated with different salts in different percentages were included in the study. Calibration models developed using partial least squares regression were cross-validated and predictive models were tested using the samples of cured ham with low sodium content. The results showed that the developed NIRS procedure is capable of directly measuring the potassium content of packaged dry-cured ham slices with low sodium content with a fitting accuracy of 91.44%, and that it can indirectly determine the sodium content by applying a correction factor to the values obtained for potassium. The prediction error between the calculated and actual sodium values determined using inductively coupled plasma atomic emission spectrophotometry (ICP-AES) was 0.004%, and this confirms that the NIRS procedure is a viable option for the determination of sodium and potassium content in this type of sample.

2.
Meat Sci ; 200: 109167, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36947977

RESUMEN

In this work, non-invasive near-infrared spectroscopy (NIRS) combined with chemometrics was evaluated as a possible online analytical technique to categorize pieces of cured ham on the industrial production line based on their maximum sodium content. Stifle muscle was selected for the development of the NIRS prediction models because it is the one with the highest sodium content and the easiest in terms of accessibility for spectral measurement. In the study, samples with varying thicknesses were taken. The suitability of this method is demonstrated when a 5 mm sample is used for the construction of the model, obtaining the best fit with an R2cv of 92% and a prediction error of 0.11% sodium that coincides with the error of the reference method. In conclusion, a method is proposed for the direct determination of sodium content on the production line which allows the different pieces of ham to be quickly categorized according to their salt content.


Asunto(s)
Carne de Cerdo , Espectroscopía Infrarroja Corta , Espectroscopía Infrarroja Corta/métodos , Carne de Cerdo/análisis , Quimiometría , Cloruro de Sodio/análisis , Cloruro de Sodio Dietético , Sodio/análisis , Análisis de los Mínimos Cuadrados
3.
SAGE Open Med ; 10: 20503121221096602, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35600705

RESUMEN

Objective: The objective of this study is to evaluate post-acute symptoms in patients with confirmed severe and critical coronavirus disease 2019 infections. Methods: We evaluated patients with confirmed severe and critical coronavirus disease 2019 infections. Post-acute symptoms were defined as symptoms persisting 4 weeks after the onset of the symptoms and classified as pulmonary, muscular, hematologic, neuropsychiatric, renal, and dermatological. Results: We recovered data from 565 patients (43.7% female) with a mean age of 61.1 years. In 18.2%, at least one hospital readmission was necessary and 11.1% died. In 62.6%, there was at least one persistent symptom, and 28.8% had more than one. Among associated factors, obesity, intensive care support, and mechanical ventilation were related to persistent symptoms. Conclusion: The most prevalent symptoms were pulmonary and neuropsychiatric sequelae, as reported in previous studies. This finding underscores the severity of the coronavirus disease 2019 infection and the need for follow-up after recovery from the initial illness. Obese patients, those requiring mechanical ventilation, female patients, and increased hospital length are at greater chance of having persistent symptoms.

4.
Int J Surg Case Rep ; 79: 14-17, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33422846

RESUMEN

INTRODUCTION AND IMPORTANCE: Carney triad is a rare entity of unknown etiology, characterized by the association of tumors with low incidence such as: gastric leiomyosarcoma, pulmonary chondroma and extra-adrenal paraganglioma. We show a case of Carney triad diagnosed in our center that has some different characteristics to the typical presentation of this patology, and a review of the literature. CASE PRESENTATION: We present the case of a 47-year-old men who was admitted to our hospital for upper gastrointestinal bleeding and anemia. The patient was diagnosed of gastric GIST (gastrointestinal stromal tumor), pulmonary nodule and retroperitoneal nodule close to iliac bifurcation. A review of his medical history revealed that he had undergone surgery at 18-year-old for gastric leiomiosarcoma, subtotal gastrectomy performed with gastroenteric anastomosis type Billroth II. The patient underwent total gastrectomy with a end-lateral esophago-jejune mechanical anastomosis and retroperitoneal tumor was also excised. Pathological result confirmed gastric GIST, and extra-adrenal paraganglioma. CLINICAL DISCUSSION: We review the available literature to determinate the characteristics and the most appropriate management for this syndrome. The trend is surgical treatment of gastric GIST and paraganglioma, preferred conservative treatment in pulmonary chondroma. It is under discussion whether gastric tumors Carney syndrome is considered GIST, because the Carney triad lesions in stomach are different clinically, pathologically, and etiologically from GIST of stomach. CONCLUSION: Carney's triad is a low prevalence entity, with a limited number of publications, so the presentation of the syndrome may be different from the presentation described in the literature.

5.
Telemed J E Health ; 27(10): 1194-1199, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33264071

RESUMEN

The objective of this communication is to offer a better understanding of the value of telemedicine in health care, particularly its role in creating opportunities for continuity of care to patients in a complex and novel setting as were the circumstances of the early COVID-19 pandemic times. Crisis time is also a time for opportunities. With regard to telehealth, all players (providers, staff, and patients) should be informed about its benefits and should also become familiar with the use of the various telehealth options and this will only be achieved through large information campaigns necessary enriched by local teaching and training programs in both public and private institutions. The final aim is to launch the debate and foster ideas useful throughout the pandemic. This article covers the experiences of physicians as well as health professionals in the Iberian Peninsula (Spain and Portugal), to provide a clearer idea of what has happened and how we can improve it with the possibilities provided by telemedicine, while at the same time to put in evidence that public health systems need to be rethought to provide solutions to situations such as that we are experiencing.


Asunto(s)
COVID-19 , Telemedicina , Atención a la Salud , Humanos , Pandemias , SARS-CoV-2
6.
Meat Sci ; 163: 108075, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32045723

RESUMEN

NIR spectroscopy combined with chemometric methods has been used to develop a prediction models of the most influential parameters in curing process of two types of hams (140 hams) using different salting techniques, lean hams salted on a tray and fatty hams in a tub, in which sodium is partially replaced. Spectral data were examined by principal component analysis and cross-validated calibration equations were developed using partial-least squares regression. Calibration errors for each parameter, obtained from cross validation (RMSECV), were similar to those obtained by reference method. For lean and fatty hams the RMSECV values were: Moisture 0.78% and 0.80; Fat 2.5 and 1.2%; Protein 0.7 and 1.7%; water activity 0.008 and 0.006; Proteolysis Index 1.6 and 1.7%; Sodium 0.11 and 0.10%; and Potassium 0.04 and 0.10. Results allow the prediction of the parameters involved in ham curing process, demonstrating the viability of the proposed method for the control and monitoring of the different stages until obtaining the final product.


Asunto(s)
Manipulación de Alimentos/métodos , Conservación de Alimentos/métodos , Productos de la Carne , Animales , Cloruro de Potasio , Proteínas/análisis , Proteolisis , Cloruro de Sodio/análisis , Espectroscopía Infrarroja Corta/métodos , Porcinos
7.
Food Chem ; 257: 237-242, 2018 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-29622205

RESUMEN

Temperature fluctuations are a key factor in the development of prediction models using near infrared spectroscopy (NIRS). In the present study, this influence has been investigated and a methodology has been proposed to reduce the effect of sample temperature on NIRS model prediction of the sodium content in dry-cured ham slices. Spectra were taken directly from the slices using a remote measurement probe (for non-contact analysis) at three different temperature ranges: -12 °C to -5°C, -5°C to 10 °C and 10 °C to 20 °C. Local and global temperature compensation methods were established. Partial-least squares (PLS) regression was used as a chemometrics tool to perform the calibrations. The results showed that local models were sensitive to changes in temperature, while a global temperature model using sample spectra over the entire temperature range showed good prediction ability, reducing the error caused by temperature fluctuations to acceptable levels for practical applications.


Asunto(s)
Análisis de los Alimentos/métodos , Carne Roja/análisis , Sodio/análisis , Espectroscopía Infrarroja Corta/métodos , Animales , Calibración , Manipulación de Alimentos/métodos , Análisis de los Mínimos Cuadrados , Temperatura
8.
Ecotoxicol Environ Saf ; 154: 154-161, 2018 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-29459165

RESUMEN

House sparrows (Passer domesticus) have been proposed as a key ecological indicator of urban pollution. Remarkably, we lack knowledge about the physiological effects of lead on this bird species. Therefore, this study was aimed to evaluate the effect of Pb on several physiological parameters in house sparrows exposed to environmental Pb concentrations. In a first experiment, birds were exposed to Pb sub-lethal doses (from 1.3 to 14.0 µg of Pb/g animal/day) during 5 days, which resulted in a dose response increase of blood Pb levels and decrease of blood ALAD activity. However, at the higher doses tested (> 7 µg of Pb/g animal/day) the blood ALAD activity inhibition (~82%) remained constant. Hematocrit and hemoglobin were significantly reduced only at the highest-doses, and the stress indicator, heterophils to lymphocyte (H/L) ratio, did not show apparent changes. In a second experiment, house sparrows were exposed to Pb in drinking water (12.3 ppm) during either 15 or 30 days. Pb concentration used in this study was enough to produce blood lead levels equivalents to those found recently in house sparrows inhabiting urban areas, reduced blood ALAD activity and inversion of the H/L ratio. Decreasing blood ALAD activities were correlated with increasing blood Pb levels. In addition, Pb exposure produced modification in the levels of hepatic antioxidant enzymes, increased GST activity and decreased CAT activity, without lipid peroxidation. In conclusion, our results suggest that blood ALAD activity is a reliable and sensitive biomarker for environmental Pb exposure in house sparrows, additionally chronic exposure produce physiological stress (H/L inversion) and small changes in antioxidant enzyme activity. Finally, this specie could be considered a bioindicator for monitoring the urban Pb contamination.


Asunto(s)
Monitoreo del Ambiente/métodos , Contaminantes Ambientales/sangre , Plomo/sangre , Estrés Oxidativo/efectos de los fármacos , Porfobilinógeno Sintasa/sangre , Gorriones/sangre , Animales , Antioxidantes/metabolismo , Argentina , Relación Dosis-Respuesta a Droga , Biomarcadores Ambientales/efectos de los fármacos , Urbanización
9.
Chemosphere ; 191: 903-910, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29145135

RESUMEN

The fate of the pharmaceutical drugs tenoxicam, piroxicam and meloxicam in river water is evaluated here for first time. So, biological, photochemical and thermal degradation assays have been conducted to estimate their degradation rates and know their degradation products. Results indicated that the direct sunlight irradiation, without any protection, promoted a fast degradation of the oxicams while the chemical reactions in solution were less important. The biological degradation in water was negligible except for tenoxicam in whose case its influence was scarce. When the exposition of river water to sunlight was partially limited and kept under the natural day-night cycle, as occurs inside a body of water, tenoxicam, piroxicam and meloxicam (at 2 µg L-1) were detected during a period of 15, 27 and 45 days, respectively. Residues were monitored by ultra-pressure liquid chromatography/quadrupole time-of-flight/mass spectrometry after solid-phase extraction and several degradation products were found (10 for tenoxicam, 9 for piroxicam and 7 for meloxicam) and monitored over time. Their structures were proposed from the molecular formulae and fragmentation observed in high-resolution tandem mass spectra; the nature of the transformation products found in the long-term resulted to be very variable for each oxicam. Furthermore, the degradation in presence of river sediment was also monitored over time, with some differences being noted; the adsorption coefficients of the compounds on sediment were calculated, meloxicam exhibited a higher sorption capacity. The ecotoxicity of the different compounds in aquatic ecosystems was predicted, too.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Ríos/química , Adsorción , Bioensayo , Cromatografía Liquida/métodos , Agua Dulce/química , Sedimentos Geológicos/química , Meloxicam , Piroxicam/análogos & derivados , Piroxicam/química , Extracción en Fase Sólida , Luz Solar , Espectrometría de Masas en Tándem , Tiazinas/química , Tiazoles/química
10.
J Hazard Mater ; 342: 252-259, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-28843794

RESUMEN

Celecoxib is an anti-inflammatory drug with antibacterial activity whose fate in surface water is unknown. Thus, some assays have been conducted under forced biological, photochemical and thermal conditions, and non-forced conditions, to establish its persistence and degradation products in river water. The results suggest that celecoxib dissolved in river water is not biologically degraded while it is minimally altered after its exposure to sunlight or high temperature (70°C). Only the irradiation at 254nm promotes its complete degradation. Celecoxib is degraded about 3%, in 36 weeks, when water was kept at room temperature and the exposure to sunlight was partially limited as it happens inside a body of water. Residues were monitored by ultra-pressure liquid chromatography/quadrupole time-of-flight/mass spectrometry after solid-phase extraction; eleven degradation products were detected and the structures of nine of them were unequivocally proposed from the molecular formulae and fragmentation observed in high-resolution tandem mass spectra. The long-term transformation products under non-forced conditions were 4-[5-(4-methylphenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl]benzenesulfonic acid, 4-[1-(4-sulfoaminephenyl)-3-(trifluoromethyl)-1H-pyrazol-5-yl]benzoic acid and a hydroxylated derivative. The degradation over time in presence of sediment was monitored, being slightly higher, about 4%. The adsorption equilibrium constants of celecoxib and degradation products on river sediment were estimated.


Asunto(s)
Celecoxib/química , Agua Dulce/análisis , Ríos/química , Extracción en Fase Sólida/métodos , Adsorción , Bioensayo , Cromatografía Liquida , Luz Solar , Espectrometría de Masas en Tándem , Agua
11.
J Environ Sci (China) ; 51: 13-20, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28115123

RESUMEN

The pharmaceutical compound indomethacin is not totally removed in wastewater treatment plants, whose effluents flow into aquatic environments; concentrations in the 0.1-100ng/L range are commonly found in surface waters, and its fate is unknown. Here, biological, photochemical and thermal degradation assays were conducted under stress and non-stress conditions to estimate its degradation rate in river water and establish its degradation products over time. The results revealed that direct sunlight irradiation promoted the complete degradation of indomethacin (2µg/L) in less than 6hr, but indomethacin was detected over a period of 4months when water was kept under the natural day-night cycle and the exposure to sunlight was partially limited, as occurs inside a body of water. The biological degradation in water was negligible, while the hydrolysis at pH7.8 was slow. Residues were monitored by ultra-pressure liquid chromatography/quadrupole time-of-flight/mass spectrometry after solid-phase extraction, and six degradation products were found; their structures were proposed based on the molecular formulae and fragmentation observed in high-resolution tandem mass spectra. 4-Chlorobenzoic and 2-acetamido-5-methoxybenzoic acids were the long-term transformation products, persisting for at least 30weeks in water kept under non-stress conditions. Furthermore, the degradation in the presence of sediment was also monitored over time, with some differences being noted. The adsorption coefficients of indomethacin and degradation products on river sediment were calculated; long-term degradation products did not have significant adsorption to sediment.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Sedimentos Geológicos/química , Indometacina/química , Contaminantes Químicos del Agua/química , Absorción Fisicoquímica , Antiinflamatorios no Esteroideos/análisis , Monitoreo del Ambiente , Modelos Químicos , Ríos/química
12.
Meat Sci ; 126: 29-35, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28002759

RESUMEN

In the present study, non-invasive near infrared spectroscopy (NIRS) was evaluated as a potential on-line analytical technique to predict the sodium content in dry-cured ham slices. Samples of 310 packages were scanned by applying a remote fibre-optic probe to the surface of the slices, at different temperatures, with no previous manipulation. The sodium content of the meat samples was determined by a reference method based on Inductively Coupled Plasma Atomic Emission Spectrophotometry (ICP-AES) after chemical digestion. Partial least squares (PLS) regression was used as a chemometrics method to perform the calibrations. The models yielded acceptable results with cross validation correlation coefficients (R2CV) determined 86.2-90.2%. The prediction capacity reached in the external validation was 3.63, with a standard prediction error of 0.12% Na. These results show that NIR measurements could be implemented on the packaging line of dry-cured ham slices to provide accurate and relevant information about the sodium content of each packaged products.


Asunto(s)
Manipulación de Alimentos , Carne Roja/análisis , Sodio/análisis , Espectroscopía Infrarroja Corta , Animales , Calibración , Análisis de los Mínimos Cuadrados , Análisis Multivariante , Análisis de Componente Principal , Reproducibilidad de los Resultados , Porcinos , Vacio
13.
Drug Test Anal ; 9(8): 1204-1213, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27992663

RESUMEN

Alprazolam is a pharmaceutical compound that it is detected in surface waters. Some degradation studies in aqueous solutions and pharmaceutical products are available, but there is no reliable information about its stability in river water. Here, assays have been conducted under forced biological, photochemical, and thermal conditions, and under non-forced conditions, to estimate the fate of alprazolam in river water and know its degradation products. The forced assays indicated that the biological and photochemical degradation of alprazolam was negligible; heating at 70°C for a long time barely affected it. The degradation of alprazolam in river water at 100 µg/L was about 5% after 36 weeks, keeping the water under a natural day-night cycle at room temperature and limiting partially the exposure to sunlight as happens inside a body of water; no change in concentration was observed when the monitoring was performed at 2 µg/L. The results suggest the persistence of alprazolam in surface water and a possible accumulation over time. Residues were monitored by ultra-pressure liquid chromatography/quadrupole time-of-flight/mass spectrometry after solid-phase extraction; nine degradation products were found and the structures for most of them were proposed from the molecular formulae and fragmentation observed in high-resolution tandem mass spectra. (5-chloro-2-(3-methyl-4H-1,2,4-triazol-4-yl)phenyl)(phenyl)methanol was the main long-term transformation product in conditions that simulate those in a mass of water. The degradation rate in presence of sediment was equally very low under non-forced conditions; adsorption coefficients of alprazolam and major degradation products were calculated. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Alprazolam/análisis , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Adsorción , Cromatografía Liquida/métodos , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos
14.
Chemosphere ; 162: 285-92, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27513549

RESUMEN

Toxic effects of the non-biodegradable drug chlorpromazine and its degradation products have been reported on microorganisms in aqueous media. Here, chlorpromazine degradation assays in forced and non-forced conditions have been done to know its persistence and degradation products in river water. Sunlight irradiation promotes the complete degradation of chlorpromazine (2 µg L(-1)) in less than 4 h, but if the exposure to sunlight is limited chlorpromazine is detected during 4 weeks in river water. Sixteen degradation products in surface water are described for first time after solid-phase extraction and analysis by ultra-pressure liquid chromatography/quadrupole time-of-flight/mass spectrometry; their structures are proposed from the molecular formulae of the fragment-ions observed in high-resolution tandem mass spectra. Hydroxylation and oxidation products such as chlorpromazine sulfoxide, 2-hydroxypromazine and 2-hydroxypromazine sulfoxide were predominant degradation products in the early stages; some benzo[1,4]thiazin-6-ol derivatives resulting from the breakdown of the phenothiazine core were the major and relatively stable products after 20 weeks under non-forced conditions. A degradation pathway of chlorpromazine in water is outlined. Moreover, it is shown that chlorpromazine is very strongly adsorbed on sediment while the degradation products that kept the promazine core have a notable capacity of sorption, too; sorption coefficients are calculated. Finally, a prediction about the toxicity of the degradation products in aquatic ecosystems suggests that some of them have toxicities similar, or even higher, than chlorpromazine.


Asunto(s)
Biodegradación Ambiental , Clorpromazina/química , Sedimentos Geológicos/química , Ríos/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Absorción Fisicoquímica , Bioensayo , Clorpromazina/metabolismo , Cromatografía Liquida/métodos , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Contaminantes Químicos del Agua/metabolismo
15.
Orphanet J Rare Dis ; 9: 217, 2014 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-25539952

RESUMEN

BACKGROUND: Kearns-Sayre syndrome (KSS) is a mitochondrial DNA deletion syndrome that presents with profound cerebral folate deficiency and other features. Preliminary data support the notion that folinic acid therapy might be useful in the treatment of KSS patients. Our aim was to assess the clinical and neuroimaging outcomes of KSS patients receiving folinic acid therapy. PATIENTS: We recruited eight patients with diagnoses of KSS. Four cases were treated at 12 de Octubre Hospital, and the other two cases were treated at Sant Joan de Déu Hospital. Two patients refused to participate in the treatment protocol. METHODS: Clinical, biochemical and neuroimaging data (magnetic resonance imaging or computed tomography scan) were collected in baseline conditions and at different time points after the initiation of therapy. Cerebrospinal fluid 5-methyltetrahydrofolate levels were analysed with HPLC and fluorescence detection. Large-scale mitochondrial DNA deletions were analysed by Southern blot. TREATMENT PROTOCOL: The follow-up periods ranged from one to eight years. Cases 1-4 received oral folinic acid at a dose of 1 mg/kg/day, and cases 6 and 8 received 3 mg/kg/day. RESULTS: No adverse effects of folinic acid treatment were observed. Cerebral 5-methyltetrahydrofolate deficiencies were observed in all cases in the baseline conditions. Moreover, all three patients who accepted lumbar puncture after folinic acid therapy exhibited complete recoveries of their decreased basal cerebrospinal fluid 5-methyltetrahydrofolate levels to normal values. Two cases neurologically improved after folinic therapy. Disease worsened in the other patients. Post-treatment neuroimaging was performed for the 6 cases that received folinic acid therapy. One patient exhibited improvements in white matter abnormalities. The remaining patients displayed progressions in subcortical cerebral white matter, the cerebellum and cerebral atrophy. CONCLUSIONS: Four patients exhibited clinical and radiological progression of the disease following folinic acid treatment. Only one patient who was treated in an early stage of the disease exhibited both neurological and radiological improvements following elevated doses of folinic acid, and an additional patient experienced neurological improvement. Early treatment with high-dose folinic acid therapy seems to be advisable for the treatment of KSS. TRIAL REGISTRATION: Eudrac T2007-00-6748-23.


Asunto(s)
Encéfalo/metabolismo , Suplementos Dietéticos , Deficiencia de Ácido Fólico/metabolismo , Síndrome de Kearns-Sayre/metabolismo , Leucovorina/administración & dosificación , Complejo Vitamínico B/administración & dosificación , Adolescente , Adulto , Niño , Femenino , Deficiencia de Ácido Fólico/dietoterapia , Estudios de Seguimiento , Humanos , Síndrome de Kearns-Sayre/dietoterapia , Imagen por Resonancia Magnética/métodos , Masculino , Adulto Joven
16.
J Hazard Mater ; 262: 71-82, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24008000

RESUMEN

The chemical fractionation patterns of eight metals (Cd, Co, Cu, Cr, Mn, Ni, Pb and Zn) have been determined in 27 metal-bearing residues by using the BCR sequential extraction procedure. The residues were generated as by-products during the optimization of a semi-continuous reactor for metal removal from wastewater based on ferrite synthesis by co-precipitation. The three-dimensional X dataset (samples×metals×fractions) obtained by applying the BCR procedure has been analyzed by multivariate methods: matrix augmentation (MA-PCA) and three-way principal component analysis, 3-PCA (PARAFAC and Tucker3 models). MA-PCA and PARAFAC methods led to two-factor models giving a satisfactory but incomplete picture of the metal fractionation patterns, but the Tucker3 [2,1,2] model allowed to simultaneously describe both the 'pseudo-total' (acid-soluble) contents and the chemical fractionation by means of two non-null interactions g111 and g212 which explain 53.5% and 18.0% of the total variance, respectively. The A-mode loadings of the g212 interaction showed the close relationship between the magnetic character of the solid residues, i.e. the crystalline structure, and the chemical fractionation patterns of the metals resulting from the application of the BCR sequential extraction procedure.


Asunto(s)
Compuestos Férricos/química , Metales/análisis , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Análisis de Componente Principal
17.
J Environ Radioact ; 124: 84-92, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23680923

RESUMEN

Coal-fired power-plants (CFPP) can be a source of contamination because the coal contains trace amounts of natural radionuclides, such as (40)K and (238)U, (232)Th and their decay products. These radionuclides can be released as fly ash from the CFPP and deposited from the atmosphere on the nearby top soils, therefore modifying the natural radioactivity background levels, and subsequently increasing the total radioactive dose received for the nearby population. In this paper, an area of 64 km(2) around the CFPP of Velilla del Río Carrión (Spain) has been studied by collecting 67 surface soil samples and measuring the activities of one artificial and six natural radionuclides by gamma spectrometry. The found results are similar to the background natural levels and ranged from 0 to 209 for (137)Cs, 11 to 50 for (238)U, 14 to 67 for (226)Ra, 29 to 380 for (210)Pb, 15 to 68 for (232)Th, 17 to 78 for (224)Ra, 97 to 790 for (40)K (all values in Bq kg(-1)). Besides the classical radiochemical tools, Analysis of Variance (ANOVA), Principal Component Analysis (PCA), Hierarchical Clustering Analysis (HCA), and kriging mapping have been used to the experimental dataset, allowing us to find the existence of two different models of spatial distribution around the CFPP. The first, followed by (238)U, (226)Ra, (232)Th, (224)Ra and (40)K can be assigned to 'natural background radioactivity', whereas the second model, followed by (210)Pb and (137)Cs, is based on 'atmospheric fallout radioactivity'. The main conclusion of this work is that CFPP has not influence on the radioactivity levels measured in the studied area, with has a mean annual outdoor effective dose E = 71 ± 22 µSv, very close to the average UNSCEAR value of 70 µSv, thus confirming the almost non-existent radioactive risk posed by the presence of the CFPP.


Asunto(s)
Centrales Eléctricas , Radioisótopos/análisis , Contaminantes Radiactivos del Suelo/análisis , Análisis de Varianza , Análisis por Conglomerados , Carbón Mineral , Humanos , Análisis de Componente Principal , Dosis de Radiación , Monitoreo de Radiación/estadística & datos numéricos , Medición de Riesgo , España , Análisis Espacial
18.
Chemosphere ; 90(2): 488-96, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22967929

RESUMEN

The study of the vertical distribution of seven radionuclides in soils around a coal fired power plant in a mountain region in the north of Spain has been performed, in order to know if some deposition and migration of these radionuclides has taken place. Thirteen profiles of 30 cm depth have been selected, and every fraction of 5 cm has been analyzed until of a total of 72 soil samples. The activity concentration of (238)U, (226)Ra, (210)Pb, (232)Th, (224)Ra, (40)K and (137)Cs has been measured by gamma-ray spectrometry. The data were analyzed using multivariate statistical techniques, founding the best result when using a simple two-factor model, which can explain the 81.1% of the total variance. Additionally, on the basis of the significant differences found in the concentration of lead in the soil top and deep layers, the evaluation of excess of (210)Pb and the K-parameter was done. A good correlation between the excess of (210)Pb and the concentration of anthropogenic radionuclide (137)Cs in surface soil was found. These results confirm the atmospheric deposition of lead as a decay product of exhaled Rn.


Asunto(s)
Centrales Eléctricas , Monitoreo de Radiación , Radioisótopos/análisis , Contaminantes Radiactivos del Suelo/análisis , Suelo/química , Carbón Mineral , España
19.
Gastroenterol Hepatol ; 35(10): 691-6, 2012 Dec.
Artículo en Español | MEDLINE | ID: mdl-23102573

RESUMEN

OBJECTIVES: To determine the diagnostic value of free perigastric fluid identified by echoendoscopy in patients with gastric cancer and to establish the factors related to the presence of peritoneal carcinomatosis in these patients. MATERIAL AND METHODS: We retrospectively included 100 patients with a histological diagnosis of gastric adenocarcinoma referred for echoendoscopy. A positive result was defined as the echoendoscopic identification of free perigastric fluid. This result was compared with the final study based on exploratory laparoscopy-laparotomy. The histological and endoscopic characteristics were compared with the final result. RESULTS: Free perigastric fluid was found in 21 patients (21%). Among these, 15 (71%) showed peritoneal carcinomatosis, confirmed by laparoscopy (12 patients) or echoendoscopy-guided fine-needle-aspiration biopsy (three patients). In seven of the 79 patients (8%) not showing the presence of ascites, peritoneal implants were identified by exploratory laparoscopy-laparotomy. The sensitivity, specificity, positive predictive value and diagnostic accuracy of free fluid in the diagnosis of carcinomatosis was 68%, 92%, 71%, 91% and 87%, respectively. No histologic or endoscopic factors related to the malignancy of echoendoscopically-detected fluid were identified. CONCLUSION: In patients with gastric cancer, free perigastric fluid identified by echoendoscopy is an important predictive factor of peritoneal carcinomatosis and may have significant implications in the management of these patients.


Asunto(s)
Líquido Ascítico/diagnóstico por imagen , Carcinoma/diagnóstico por imagen , Endosonografía , Neoplasias Peritoneales/secundario , Neoplasias Gástricas/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Ascitis/etiología , Ascitis/fisiopatología , Líquido Ascítico/citología , Biopsia con Aguja Fina/métodos , Carcinoma/complicaciones , Carcinoma/fisiopatología , Carcinoma/cirugía , Femenino , Humanos , Laparoscopía , Laparotomía , Masculino , Persona de Mediana Edad , Neoplasias Peritoneales/complicaciones , Neoplasias Peritoneales/diagnóstico por imagen , Neoplasias Peritoneales/fisiopatología , Neoplasias Peritoneales/cirugía , Estudios Retrospectivos , Neoplasias Gástricas/cirugía , Ultrasonografía Intervencional
20.
Artículo en Inglés | MEDLINE | ID: mdl-22755532

RESUMEN

(131)I, commonly used in nuclear medicine, can be incorporated into the human body in a variety of chemical and physical forms. This study describes a sensitive method for the determination of (131)I concentration and its application to the estimation of the amount of airborne (131)I inhaled by staff workers of a Nuclear Medicine Department. Our method uses passive sampling with charcoal canisters followed by liquid scintillation counting, a very sensitive technique for the determination of low concentrations of airborne (131)I. We have studied the effects caused on the measured (131)I concentration in air by both, the doses administered to the patients and the distance of sampling canisters to the patient. We have found a direct relationship between the amount of (131)I activity administered and the airborne (131)I activity concentration. We have estimated the contribution of inhaled (131)I to the effective dose received by staff, finding differences between physicians and non-physician personnel. However, the measured exposure was quite low in both cases, thus suggesting that there is no need to introduce additional safety measures to the current ones.


Asunto(s)
Radioisótopos de Yodo/análisis , Medicina Nuclear , Exposición Profesional/análisis , Conteo por Cintilación/métodos , Femenino , Humanos , Masculino , Dosis de Radiación
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