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1.
Ultrasonics ; 138: 107216, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38070441

RESUMO

This research investigates the temperature-dependent variation of diverse acoustic parameters in samples of edible oils. It further supplements previous studies on the effectiveness of non-destructive ultrasonic inspection in the authentication of edible oils. The oils under examination consist of pure samples of olive, sunflower, and corn oils, as well as variable mixtures ranging from 20 % to 80 % of the more expensive one (olive oil) with the other two, simulating a hypothetical adulteration scenario. The studied acoustic parameters are related to the velocity, attenuation, and frequency components present in 2.25 MHz ultrasonic waves propagating through the oil samples within a temperature range of 24 °C to 34 °C. The results confirm the suitability of non-destructive ultrasonic inspection in evaluating and detecting the adulteration of olive oil with economically inferior oils such as sunflower and corn. Additionally, this study provides added value by laying the groundwork for a non-destructive and innovative determination of the fatty acid profile of an edible oil based on the evolution of the aforementioned ultrasonic parameters with temperature. The findings hold potential for enhancing the authenticity assessment and quality control of edible oils in the food industry.


Assuntos
Óleos de Plantas , Ultrassom , Azeite de Oliva/análise , Temperatura
2.
Food Chem ; 429: 136820, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37531872

RESUMO

At present, the quality of edible oil is evaluated using traditional analysis techniques that are generally destructive. Therefore, efforts are being made to find alternative methods with non-destructive techniques such as Ultrasound. This work aims to confirm the feasibility of non-destructive ultrasonic inspection to characterise and detect fraudulent practices in olive oil due to adulteration with two other edible vegetable oils (sunflower and corn). For this purpose, pulsed ultrasonic signals with a frequency of 2.25 MHz have been used. The samples of pure olive oil were adulterated with the other two in variable percentages between 20% and 80%. Moreover, the viscosity and density values were measured. Both these physicochemical and acoustic parameters were obtained at 24 °C and 30 °C and linearly correlated with each other. The results indicate the sensitivity of the method at all levels of adulteration studied. The responses obtained through the parameters related to the components of velocity, attenuation, and frequency of the ultrasonic waves are complementary to each other. This allows concluding that the classification of pure and adulterated oil samples is possible through non-destructive ultrasonic inspection.


Assuntos
Contaminação de Alimentos , Óleos de Plantas , Azeite de Oliva/análise , Contaminação de Alimentos/análise , Óleos de Plantas/análise , Ondas Ultrassônicas , Acústica
3.
J Environ Radioact ; 100(3): 209-14, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19128862

RESUMO

The Almaraz nuclear power plant (Spain) uses the water of Arrocampo reservoir for cooling, and consequently raises the radioactive levels of the aquatic ecosystem of this reservoir. From July 2002 to June 2005, monthly samples of surface water, bulrushes (Typha latifolia) and carp (Cyprinus carpio) were collected from this reservoir. They were analyzed to determine the temporal evolution of the levels of (3)H in surface water and of its transfer from the surface water to free-water in the tissues (TFWT) of the aforementioned two organisms. The tritium levels in the surface water oscillate with a biannual period, with their values in the study period ranging between 53 and 433 Bq/L. The incorporation of tritium to bulrushes and carp was fairly similar, the respective mean concentration factors being 0.74 and 0.8 (unitless, as Bq/L tissue water per Bq/L reservoir water). The temporal evolution of the levels fairly closely followed that observed for the surface water tritium, although detailed analysis showed the dominant periodicity for the bulrushes to be annual. This difference reflects the influence on the incorporation of tritium to bulrushes of diverse environmental and metabolic factors, especially evapotranspiration and the seasonal growth of this plant.


Assuntos
Carpas , Centrais Nucleares , Monitoramento de Radiação , Trítio/análise , Typhaceae/química , Água/química , Animais , Modelos Lineares , Modelos Teóricos , Estações do Ano , Espanha
4.
Ann Oncol ; 20(1): 91-7, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18664559

RESUMO

BACKGROUND: Occult lymph node (LN) metastases are clinically relevant and confer a worse prognosis in non-small-cell lung cancer (NSCLC) patients. Current staging methods are unable to identify patients with poor outcome. Their detection requires both a more sensitive and specific technique. We aimed to assess the role of messenger RNA expression in pathologically negative LNs (pN0) of stage I NSCLC patients as markers of occult micrometastases and to correlate the results with local or distant tumor recurrence and survival. PATIENTS AND METHODS: Potential molecular markers were evaluated in 344 LNs and 38 tumors by quantitative real-time RT-PCR. Only CEACAM5 and PLUNC showed high expression in lung tumor tissue and null expression in RNA from benign LNs. RESULTS: Thirteen per cent of the LNs were positive for CEACAM5 and 16% for PLUNC. Eight of 38 NSCLC patients had positive expression in pN2 nodes by CEACAM5 and/or PLUNC and disease-free survival (P=0.028) and overall survival time was significantly worse in these patients compared with those with negative expression (P=0.0083). CONCLUSIONS: Quantitative real-time RT-PCR of CEACAM5 and PLUNC can estimate the presence of micrometastatic cells in LNs with greater precision than current staging method used for assessing tumor recurrence risk.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Neoplasias do Mediastino/secundário , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/fisiologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/cirurgia , Linfonodos/metabolismo , Linfonodos/patologia , Metástase Linfática , Masculino , Neoplasias do Mediastino/genética , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Recidiva , Carga Tumoral/genética
5.
Arch Bronconeumol ; 41(4): 185-8, 2005 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-15826527

RESUMO

OBJECTIVE: To detect the tumor marker carcinoembryonic antigen (CEA) in pleural lavage fluid taken during surgery from patients with pulmonary carcinoma without associated pleural effusion and assess its possible prognostic implications. PATIENTS AND METHODS: A prospective, observational study was undertaken to include consecutive patients who underwent surgical treatment for lung carcinoma in which pleural lavage was performed prior to closure of the thoracic cavity (study group). The same techniques and measurements were used in patients undergoing thoracotomy for benign disease (control group). The preoperative blood level of CEA was also quantified. RESULTS: In the study group, the median CEA levels in blood and pleural lavage fluid were 2.90 ng/mL and 0.40 ng/mL respectively; these figures are higher than those corresponding to the control group. A CEA level of 0.30 ng/mL in pleural lavage fluid was established as a cutoff point, based on the corresponding receiver operating characteristic curve, with a sensitivity of 68.4% and a specificity of 35.7%. A graph of survival in relation to this cutoff point revealed a statistically significant effect (P<.05). CONCLUSIONS: It is possible to detect CEA in pleural lavage fluid from the thoracic cavity of patients with lung carcinoma. The values obtained are higher than those found in fluid from patients without neoplastic disease, and this parameter functions as an independent predictor of disease course.


Assuntos
Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Antígeno Carcinoembrionário/análise , Antígeno Carcinoembrionário/metabolismo , Neoplasias Pulmonares/metabolismo , Derrame Pleural Maligno/química , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Irrigação Terapêutica
6.
Arch Bronconeumol ; 40(9): 419-21, 2004 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-15458619

RESUMO

Solitary fibrous tumors of the pleura are uncommon and mainly arise in the pleura itself. Such tumors are generally asymptomatic and slow-growing. We report a series of 10 cases (8 men and 2 women with a mean age of 58.6 years) treated over a period of 54 months. The tumors were classified histologically as benign or malignant according to the criteria used by England. The treatment of choice was complete resection of the tumor. Six posterolateral thoracotomies and 4 video-assisted resections were performed. Histology showed a mixture of fibroblast-like cells and collagenous stroma. Sarcomatous degeneration was observed in the excised tumor of 1 patient. The patients were followed for a mean of 23.9 months. We conclude that although fibrous tumors of the pleura are considered benign histologically, complete resection and follow up for all patients are recommended.


Assuntos
Fibroma , Mesotelioma , Neoplasias Pleurais , Adulto , Idoso , Broncoscopia , Feminino , Fibroma/diagnóstico , Fibroma/patologia , Fibroma/cirurgia , Seguimentos , Humanos , Masculino , Mesotelioma/diagnóstico , Mesotelioma/patologia , Mesotelioma/cirurgia , Pessoa de Meia-Idade , Pleura/patologia , Neoplasias Pleurais/diagnóstico , Neoplasias Pleurais/patologia , Neoplasias Pleurais/cirurgia , Radiografia Torácica , Cirurgia Torácica Vídeoassistida , Toracotomia , Fatores de Tempo , Tomografia Computadorizada por Raios X
7.
Ultrasonics ; 42(1-9): 527-30, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15047341

RESUMO

In this study, we describe a technique which can be used to characterize some relevant properties of 26 cylindrical samples (15 x 30 cm2) of concrete. The characterization has been performed, according to Spanish regulations in force, by some destructive and ultrasound-based techniques using frequencies of 40 kHz. Samples were manufactured using different water/cement ratios (w/c), ranging from 0.48 to 0.80, in order to simulate different values of compressive strength at each sample. We have correlated the propagation velocity v of ultrasonic waves through the samples to compressive strength R values. As some other authors remark, there exists an exponential relationship between the two above parameters. We have found that a highly linear relationship is present between R and w/c concentration at the samples. Nevertheless, when the same linear model is adopted to describe the relationship between v and w/c, the value of r decreases significantly. Thus, we have performed a multiple regression analysis which takes into account the impact of different concrete constituents (water, cement, sand, etc.) on ultrasound propagation speed. One of the most relevant practical issues addressed in our study is the estimation of the hardening curve of concrete, which can be used to quantify the viability of applying the proposed method in a real scenario. Subsequently, we also show a detailed analysis of the temporal evolution of v and R through 61 days, beginning at the date where the samples were manufactured. After analyzing both parameters separately, a double reciprocal relationship is deduced. Using the above parameters, we develop an NDE-based model which can be used to estimate hardening time of concrete samples.

8.
Arch Bronconeumol ; 39(11): 527-30, 2003 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-14588207

RESUMO

Inflammatory pseudotumors are rare entities which occasionally affect the pulmonary parenchyma. Their clinical diagnosis arises in a variety of ways and half the time they are detected by chance. Deciding on a therapeutic approach is difficult because a firm diagnosis is established only after studying the excised tissue. We describe our experience with the diagnosis, surgical treatment, and follow up of 4 cases of inflammatory pseudotumor located in the pulmonary parenchyma and treated by surgical resection (by thoracotomy or video assisted thoracoscopic surgery) with good outcomes following complete resection.


Assuntos
Granuloma de Células Plasmáticas Pulmonar/patologia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade
9.
Arch Bronconeumol ; 39(7): 310-3, 2003 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-12846960

RESUMO

The aim of this prospective study was to evaluate video-assisted thoracoscopic surgery (VATS) in primary and secondary spontaneous pneumothoraces. Over a 37-month period, 107 videothoracoscopic interventions were performed to treat spontaneous pneumothorax in 105 patients, 78 men and 27 women, whose average age was 28 years.Indications for surgery included recurrent ipsilateral pneumothorax (47 cases), persistent air leak (23 cases), hypertensive pneumothorax (14 cases), history of contralateral pneumothorax (13 cases), and elective surgery (10 cases). All of these patients were treated by endoscopic resection of the bullae (or apical zone in cases where the suspected abnormalities, or bullae, could not be visualized) plus physical pleurodesis. There were no perioperative deaths. Complications occurred in 6% of the cases of primary spontaneous pneumothorax and in 45% of the cases of secondary spontaneous pneumothorax. The complications among the secondary pneumothorax patients ranged widely from postoperative subcutaneous emphysema (resolved through simple, unassisted observation) to the need for an accessory minithoracotomy. Two patients (1.8%) suffered a recurrence of pneumothorax 4 and 8 months, respectively, after VATS treatment.


Assuntos
Pneumotórax/cirurgia , Cirurgia Torácica Vídeoassistida , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Cirurgia Torácica Vídeoassistida/efeitos adversos , Cirurgia Torácica Vídeoassistida/métodos
11.
Arch Bronconeumol ; 37(9): 397-400, 2001 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-11674941

RESUMO

We report five cases of spontaneous pneumothorax as the first sign of pulmonary carcinoma. Initial tests did not detect neoplasms. Diagnosis took place during surgery for four patients and the fifth was diagnosed by preoperative computed tomography to assess pulmonary bullous emphysema. All five patients had persistent air leaks in spite of correct placement and functioning of drains, the reason for which surgery was scheduled. Three segmentectomies, one lobectomy and one exploratory thoracotomy for pleural metastasis were performed. Histopathologic diagnoses were 3 giant cell tumors, 1 adenocarcinoma and 1 non-mucinous bronchoalveolar carcinoma. We think that when risk factors are present, the existence of unresolved pneumothorax after correct placement of a drain should lead to a suspicion of associated pulmonary carcinoma.


Assuntos
Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/diagnóstico , Pneumotórax/etiologia , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade
14.
Appl Radiat Isot ; 53(3): 455-62, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10972153

RESUMO

There has been an extraordinary increase in interest concerning the transfer of radioactive contamination to the fruit bodies of fungi since the Chernobyl nuclear power plant accident. These investigations, however, have focused exclusively on field studies aimed fundamentally at quantifying the behaviour of the radiocaesium component of the contamination. The results have shown great variability. As a contribution towards this body of knowledge, we have made a comparative study of the temporal evolution of the transfer of 85Sr and 134Cs via three routes of radioactive contamination--from the mycelium, from the surface layer of the soil, and directly onto the caps of the fruit bodies--for the saprophyte species, Pleurotus eryngii, under controlled laboratory conditions. The results indicate that the last of the above three uptake routes is the most efficient, and that the temporal evolution of the transfer is closely related to the radionuclide and the radioactive contamination route being considered.


Assuntos
Poluentes Radioativos do Ar/farmacocinética , Radioisótopos de Césio/farmacocinética , Pleurotus/fisiologia , Poluentes Radioativos do Solo/farmacocinética , Radioisótopos de Estrôncio/farmacocinética , Transporte Biológico , Liberação Nociva de Radioativos , Ucrânia
15.
Appl Radiat Isot ; 50(3): 467-74, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10070709

RESUMO

One of the immediate consequences of massive radioisotope release into the atmosphere is contamination of the biosphere. This contamination can affect plants either by direct deposition onto the leaves, or by contaminating the soil followed by absorption by the roots. Knowledge of the efficacy of the two routes of radionuclide incorporation into the food chain is fundamental to understanding the mechanisms by which radioactive contamination reaches man. The present work analyzes the incorporation of 134Cs and 85Sr via root and leaf uptake into the parts consumed by man, for two very different crops: turnip (Brassica napus) and broad bean (Vicia faba). The root uptake studies consider the available soil fraction for these two radionuclides, and indicate greater availability for 85Sr than for 134Cs which is fixed rapidly in the soil. For the study of leaf uptake, leaves were contaminated at three different stages of plant growth; the results indicate an inverse dependence of the transfer coefficients on the time elapsed from the moment of the contamination to harvesting of the edible parts.


Assuntos
Radioisótopos de Césio/farmacocinética , Contaminação Radioativa de Alimentos , Radioisótopos de Estrôncio/farmacocinética , Poluentes Radioativos do Ar/farmacocinética , Transporte Biológico Ativo , Brassica/metabolismo , Fabaceae/metabolismo , Contaminação Radioativa de Alimentos/análise , Humanos , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Plantas Medicinais , Poluentes Radioativos do Solo/farmacocinética
16.
Arch Bronconeumol ; 32(8): 388-93, 1996 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-8983565

RESUMO

Bronchoplasty in oncological surgery is performed to remove a tumor while preserving most of the pulmonary parenchyma. Survival in selected patients is similar to survival after lung removal. We report a series of 50 bronchoplastic procedures performed in 37 patients with bronchopulmonary cancer. Twelve had carcinoid tumors and 1 had single lung metastasis from adenocarcinoma of the colon. Twenty-seven operations were performed on the right side and 23 on the left. The pulmonary parenchyma was not resected in 2 patients. The pulmonary artery was also repaired in 5 patients. Mortality at 30 days was 2% (1 patient) and survival at 5 years was 47% calculated according to the method of Kaplan-Meier. Survival was 37 months in only 1 of the 8 patients with mediastinal adenopathy, for whom complementary radiation therapy was provided. Survival among the patients with carcinoid tumors is 91.6% to date, as all but 1 are alive at present. The single death was due to intestinal diverticulosis. The patient with metastasis is alive 12 years after surgery. Spirometric function tests were performed in 17 patients 1 year after surgery and ventilation perfusion was studied in 13. A slight loss of forced vital capacity and maximum expiratory volume in 1 second, while ventilation perfusion corresponding to the parenchyma preserved was normal. Bronchoplasty is the treatment of choice for endobronchial tumors with low degrees of malignancy. Bronchoplasty is an effective surgical treatment for a select group of carcinomas.


Assuntos
Brônquios/cirurgia , Neoplasias Pulmonares/cirurgia , Adenocarcinoma/cirurgia , Adolescente , Adulto , Idoso , Tumor Carcinoide/cirurgia , Carcinoma de Células Escamosas/cirurgia , Criança , Pré-Escolar , Feminino , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/fisiopatologia , Masculino , Fluxo Expiratório Máximo , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Análise de Sobrevida , Capacidade Vital
17.
Appl Radiat Isot ; 46(10): 1053-9, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7496372

RESUMO

In an extensive study of different types of water in the province of Cáceres (Spain) in order to determine their total alpha- and total beta-radioactivity contents, several factors were found to have a decisive influence on their radioactivity levels. Thus, parameters such as total hardness and pH can be determinative according to the lithological type of the aquifer or according to the subterranean or surface origin of the hydrological resource. Waters from classic lithologies, or originating from a well, possess above-average radioactivity indices, surpassing in numerous cases the indicative levels set by current Spanish legislation. In contrast, surface waters from rivers, in practically all cases, possess below-average radioactivity indices.


Assuntos
Poluentes Radioativos da Água/análise , Contaminação Radioativa da Água/análise , Água Doce , Geografia , Humanos , Produtos de Decaimento de Radônio/análise , Espanha , Abastecimento de Água/normas
20.
Health Phys ; 55(6): 863-7, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3198396

RESUMO

Levels of 137Cs and 134Cs resulting from the Chernobyl nuclear accident were studied in 195 birds that winter in two regions of Spain. Only five of the 12 species examined were contaminated. The average values for 137Cs vary between 1.6 and 41 Bq kg-1 fresh. In particular, the contamination for song-thrushes (Turdus philomelos) are compared between the regions of Extremadura and Valencia, 350 km east of Extremadura at the same latitude. The results show that the contamination of birds wintering in Spain decreases from east to west. The whole-body dose commitment for humans consuming these contaminated birds was calculated. The values are well below the established ICRP guideline.


Assuntos
Acidentes , Aves/metabolismo , Radioisótopos de Césio/análise , Reatores Nucleares , Animais , Contaminação Radioativa de Alimentos/análise , Espanha , Ucrânia
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