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1.
Ecotoxicol Environ Saf ; 264: 115398, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37634482

RESUMO

Pesticide exposure is an important driver of bee declines. Laboratory toxicity tests provide baseline information on the potential effects of pesticides on bees, but current risk assessment schemes rely on one species, the highly social honey bee, Apis mellifera, and there is uncertainty regarding the extent to which this species is a suitable surrogate for other pollinators. For this reason, Osmia cornuta and Osmia bicornis have been proposed as model solitary bee species in the EU risk assessment scheme. The use of solitary bees in risk assessment requires the development of new methodologies adjusted to the biology of these species. For example, oral dosing methods used with honey bees cannot be readily applied to solitary bees due to differences in feeding behaviour and social interactions. In this study, we describe the "petal method", a laboratory feeding method, and validate its use in acute and chronic exposure oral tests with Osmia spp. We conducted five experiments in which we compared the performance of several artificial flowers combining visual and olfactory cues against the petal method, or in which variations of the petal method were confronted. We then use the results of these experiments to optimize the feeding arenas and propose standardized methods for both acute and chronic exposure tests. The petal method provides high levels of feeding success, thus reducing the number of bees needed. It works with a wide variety of petal species and with both female and male Osmia spp., thus ensuring reproducibility across studies. To validate the use of the petal method in ecotoxicology tests, we assess the toxicity of a standard reference insecticide, dimethoate, in O. cornuta adults and determine LD50 values for this species. The petal method should facilitate the inclusion of solitary bees in risk assessment schemes therefore increasing the protection coverage of pesticide regulation.


Assuntos
Inseticidas , Praguicidas , Masculino , Abelhas , Feminino , Animais , Praguicidas/toxicidade , Reprodutibilidade dos Testes , Inseticidas/toxicidade , Flores , Testes de Toxicidade
2.
Clin Oncol (R Coll Radiol) ; 33(5): 322-330, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33358283

RESUMO

AIMS: Moderately hypofractionated breast irradiation has been evaluated in several prospective studies, resulting in wide acceptance of shorter treatment protocols for postoperative breast irradiation. Reimbursement for radiation therapy varies between private and public systems and between countries, impacting variably financial considerations in the use of hypofractionation. The aim of this study was to evaluate the financial impact of moderately hypofractionated breast irradiation by reimbursement system in different countries. MATERIALS AND METHODS: The study was designed by an international group of radiation oncologists. A web-questionnaire was distributed to representatives from each country. The participants were asked to involve the financial consultant at their institution. RESULTS: Data from 13 countries from all populated continents were collected (Europe: Denmark, France, Italy, the Netherlands, Spain, UK; North America: Canada, USA; South America: Brazil; Africa: South Africa; Oceania: Australia; Asia: Israel, Taiwan). Clinicians and/or departments in most of the countries surveyed (77%) receive remuneration based on the number of fractions delivered to the patient. The financial loss per patient estimated resulting from applying moderately hypofractionated breast irradiation instead of conventional fractionation ranged from 5-10% to 30-40%, depending on the healthcare provider. CONCLUSION: Although a generalised adoption of moderately hypofractionated breast irradiation would allow for a considerable reduction in social and economic burden, the financial loss for the healthcare providers induced by fee-for-service remuneration may be a factor in the slow uptake of these regimens. Therefore, fee-for-service reimbursement may not be preferable for radiation oncology. We propose that an alternative system of remuneration, such as bundled payments based on stage and diagnosis, may provide more value for all stakeholders.


Assuntos
Neoplasias da Mama , Hipofracionamento da Dose de Radiação , Mama , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Fracionamento da Dose de Radiação , Feminino , Humanos , Estudos Prospectivos
3.
Toxicol Lett ; 334: 27-35, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956827

RESUMO

Methyl- and propyl- parabens are generally regarded as safe by the U.S Food and Drug Administration and as such are commonly used in personal care products. These parabens have been associated with increased white adipogenesis in vitro and methyl paraben also increased the white adipose mass of mice. Given brown adipose also plays a role in energy balance, we sought to evaluate whether the effects of methyl- and propyl- parabens on white adipocytes extended to brown adipocytes. We challenged white and brown pre-adipocytes at low doses of both parabens (up to 1 µM) during the differentiation process and examined adipogenesis with the ORO assay. The impact of each paraben on glucose uptake and lipolytic activity of adipocytes were measured with a fluorescent glucose analog and enzymatically, respectively. Methyl- and propyl- parabens increased adipogenesis of 3T3-L1 white adipocytes but not brown adipocytes. In white adipocytes, methyl paraben increased glucose uptake and both parabens reduced basal lipolysis. However, in brown adipocytes, parabens had no effect on basal lipolysis and instead attenuated isoproterenol induced lipolysis. These data indicate that methyl- and propyl- parabens target the differentiation and metabolic processes of multiple types of adipocytes in a cell autonomous manner.


Assuntos
Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Parabenos/toxicidade , Conservantes Farmacêuticos/toxicidade , Células 3T3-L1 , Adipócitos/metabolismo , Adipócitos/patologia , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Marrom/patologia , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/patologia , Animais , Diferenciação Celular/efeitos dos fármacos , Cosméticos , Glucose/metabolismo , Lipólise/efeitos dos fármacos , Camundongos
4.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30139594

RESUMO

Radiotherapy is a treatment with curative intent, both in patients with primary diagnosis of prostate cancer (PCa) and in patients presenting with biochemical recurrence after radical prostatectomy (RP). Moreover, the use of stereotactic body radiotherapy as a metastasis directed therapy in patients with oligometastatic PCa has significantly increased in the recent years. Conventional imaging techniques, including transrectal ultrasound, computed tomography (CT), morphologic magnetic resonance and bone scintigraphy have traditionally played a minor role in all those clinical scenarios due to its low diagnostic accuracy. The recent development of the positron emission tomography (PET) radiotracer 68Ga-PSMA binding to the prostate specific membrane antigen (PSMA), a transmembrane glycoprotein overexpressed in PCa cells, has shown promising results. Detection rates for PCa lesions are higher than CT and higher than the best technique available, the PET/CT with choline. Its superiority has been demonstrated even at very low PSA levels (<1 ng/ml). This increase in diagnostic accuracy represents a potential impact on patient management, especially in radiotherapy. Even if this imaging technique is already available for routine clinical practice in some European countries, in Spain, unfortunately, there is very limited access. In this review, we analyze the main studies that investigate the usefulness of 68Ga-PSMA PET/CT in patients with PCa and its potential impact on radiotherapy treatments. In addition, we compared the 68Ga-PSMA PET/CT, with the multiparametric magnetic resonance imaging and the PET/CT with choline, in the different clinical scenarios.


Assuntos
Glicoproteínas de Membrana , Compostos Organometálicos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Compostos Radiofarmacêuticos , Isótopos de Gálio , Radioisótopos de Gálio , Hospitais , Humanos , Masculino , Recidiva Local de Neoplasia/diagnóstico por imagem , Radioterapia (Especialidade)
5.
Clin Transl Oncol ; 20(11): 1484-1491, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29992463

RESUMO

PURPOSE: To investigate patterns of practice among Spanish radiation oncologists in the use of multiparametric magnetic resonance imaging (mpMRI) for the treatment of prostate cancer (PCa). We evaluated (1) access to mpMRI, (2) current clinical practices, and (3) physician expectations of mpMRI. METHODS: Cross-sectional survey of 118 radiation oncologists at 75 Radiation Oncology (RO) departments in Spain. RESULTS: A total of 55 radiation oncologists from 52 RO departments (52/75; 69%) completed the survey. Prostate mpMRI is performed at 94.5% of the centres that provided data. The most common indications for mpMRI in routine clinical practice were: (1) detection/localization of the tumour prior to second biopsy (82.7%), (2) cancer staging (80.8%), and (3) detection of recurrence after definitive treatment (80.8%). Most respondents (72.7%) reported modifying the primary radiotherapy treatment when mpMRI findings indicate a more advanced T stage with a resultant change in the risk group. Most respondents (90.5%) treat macroscopic local recurrence after prostatectomy with high doses, ranging from 71 to 83 Gy; in 37.7% of cases, the full dose is delivered to the entire prostate bed. In pelvic nodal recurrence, more than half (59.3%) of the respondents reported performing elective pelvic radiotherapy, including the prostate bed, with a boost to the involved nodes. CONCLUSIONS: This survey shows that prostate mpMRI is routinely used by radiation oncologists in Spain in a wide range of clinical scenarios. The findings reported here underscore the need to standardize treatment protocols for definitive and salvage radiotherapy in patients evaluated with mpMRI.


Assuntos
Imageamento por Ressonância Magnética , Padrões de Prática Médica/estatística & dados numéricos , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Radio-Oncologistas/estatística & dados numéricos , Estudos Transversais , Humanos , Masculino , Próstata/patologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Radio-Oncologistas/educação , Espanha , Inquéritos e Questionários
6.
Radiat Oncol ; 10: 262, 2015 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-26704623

RESUMO

PURPOSE/OBJECTIVE: Little is known about the clinical impact of using multiparametric MRI to plan early salvage radiotherapy after radical prostatectomy. We aimed to evaluate the incidence and location of recurrence based on pelvic multiparametric MRI findings and to identify clinical variables predictive of positive imaging results. MATERIALS AND METHODS: We defined radiological criteria of local and lymph node malignancy and reviewed records and MRI studies of 70 patients with PSA recurrence after radical prostatectomy. We performed univariate and multivariate analysis to identify any association between clinical, pathological and treatment-related variables and imaging results. RESULTS: Multiparametric MRI was positive in 33/70 patients. We found local and lymph node recurrence in 27 patients and 7 patients, respectively, with a median PSA value of 0.38 ng/ml. We found no statistically significant differences between patients with positive and negative multiparametric MRI for any variable. Shorter PSADT was associated with positive lymph nodes (median PSADT: 5.12 vs 12.70 months; p: 0.017). CONCLUSIONS: Nearly half the patients had visible disease in multiparametric MRI despite low PSA. Positive lymph nodes incidence should be considered when planning salvage radiotherapy, particularly in patients with a short PSADT.


Assuntos
Metástase Linfática/patologia , Imageamento por Ressonância Magnética , Recidiva Local de Neoplasia/patologia , Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Humanos , Interpretação de Imagem Assistida por Computador , Metástase Linfática/radioterapia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/radioterapia , Pelve/patologia , Prostatectomia , Neoplasias da Próstata/cirurgia , Radioterapia/métodos , Estudos Retrospectivos , Terapia de Salvação/métodos
7.
Toxicol In Vitro ; 29(7): 1639-46, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26100224

RESUMO

Exposure to mycotoxins through dietary food intake involves a highly complex scenario where co-contamination of different mycotoxins has been frequently demonstrated. On the other hand, the effect of the interaction of mycotoxins with other generally considered beneficial food components, as the antioxidants, has been scarcely studied. The main goal of the present work was to assess the cytotoxic effects on Caco-2 cells of the mycotoxins deoxynivalenol (DON) and ochratoxin A (OTA), alone or combined, and to explore potential protective effects of resveratrol (RES), an antioxidant frequently found in wine. In parallel, reactive oxygen species (ROS) production has also been studied as a first approach to understand the underlying mechanism of cytotoxicity. Results indicate a higher toxic effect of the mycotoxins when they are co-exposed. This increase in cytotoxicity was not accompanied by an increase in ROS production. The co-exposure of OTA or DON with RES did not result in a decrease in cytotoxicity; on the contrary, it resulted in increased cytotoxicity not associated with an increase in ROS production.


Assuntos
Ocratoxinas/toxicidade , Tricotecenos/toxicidade , Antioxidantes/farmacologia , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Interações Medicamentosas , Humanos , Espécies Reativas de Oxigênio/metabolismo , Resveratrol , Estilbenos/farmacologia
8.
Environ Res ; 143(Pt B): 65-71, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25985745

RESUMO

In the last decades, awareness regarding personal care products (PCP), i.e. synthetic organic chemicals frequently used in cosmetic and hygienic products, has become a forward-looking issue, due to their persistency in the environment and their potential multi-organ toxicity in both human and wildlife. Seafood is one of the most significant food commodities in the world and, certainly, one of the most prone to bioaccumulation of PCP, what can consequently lead to human exposure, especially for coastal population, where its consumption is more marked. The aim of this work was to evaluate the co-occurrence of musk fragrances and UV-filters in both seafood and macroalgae collected in different European hotspots (areas with high levels of pollution, highly populated and near wastewater treatment plants). Despite the fact that UV-filters were detected in three different kind of samples (mussel, mullet, and clam), in all cases they were below the limit of quantification. Galaxolide (HHCB) and tonalide (AHTN) were the musk fragrances most frequently detected and quantified in samples from the European hotspots. Cashmeran (DPMI) was also detected in most samples but only quantified in two of them (flounder/herring and mullet). The highest levels of HHCB and AHTN were found in mussels from Po estuary.


Assuntos
Monitoramento Ambiental/métodos , Perfumes/análise , Alimentos Marinhos/análise , Alga Marinha/química , Protetores Solares/análise , Animais , Bivalves/química , Europa (Continente) , Peixes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Reprodutibilidade dos Testes , Alimentos Marinhos/normas , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem
9.
J Fish Biol ; 86(2): 827-833, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25557804

RESUMO

Prolonged and high-speed swimming performance measurements were used to explore the swimming abilities of two species of estuarine fishes, the mummichog Fundulus heteroclitus and the striped killifish Fundulus majalis, under different salinities. Critical swimming performance was significantly higher for F. majalis in high salinity than in low salinity, but no difference was observed in brief constant acceleration swimming trials in this species; however, the swimming performance of F. heteroclitus was not significantly affected by salinity changes, indicating that this species is well adapted to regular estuarine salinity oscillations. Fundulus majalis displayed higher swimming speeds than F. heteroclitus in both high and low salinities, and while this cannot be explained by their respective salinity preferences, the specific habitat preferences of F. majalis for sandy subtidal habitats and F. heteroclitus for vegetated marshes could explain the better swimming performance of F. majalis.

10.
Clin Transl Oncol ; 16(5): 447-54, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24682792

RESUMO

AIM: The purpose of the study was to describe infrastructures, treatment modalities, and workload in radiation oncology (RO) in Spain, referred particularly to prostate cancer (PC). METHODS: An epidemiologic, cross-sectional study was performed during 2008-2009. A study-specific questionnaire was sent to the 108 RO-registered departments. RESULTS: One hundred and two departments answered the survey, and six were contacted by telephone. Centers operated 236 treatment units: 23 (9.7 %) cobalt machines, 37 (15.7 %) mono-energetic linear accelerators, and 176 (74.6 %) multi-energy linear accelerators. Sixty-one (56.4 %) and 33 (30.5 %) departments, respectively, reported intensity-modulated radiation therapy (IMRT) and image-guided RT (IGRT) capabilities; three-dimensional-conformal RT was used in 75.8 % of patients. Virtual simulators were present in 95 departments (88.0 %), 35 use conventional simulators. Fifty-one departments (47.2 %) have brachytherapy units, 38 (35.2 %) perform prostatic implants. Departments saw a mean of 24.9 new patients/week; the number of patients treated annually was 102,054, corresponding to 88.4 % of patients with a RT indication. In 56.5 % of the hospitals, multidisciplinary teams were available to treat PC. CONCLUSIONS: Results provide an accurate picture of current situation of RO in Spain, showing a trend toward the progressive introduction of new technologies (IMRT, IGRT, brachytherapy).


Assuntos
Departamentos Hospitalares/organização & administração , Neoplasias da Próstata/radioterapia , Radioterapia (Especialidade) , Carga de Trabalho , Estudos Transversais , Humanos , Masculino , Espanha , Inquéritos e Questionários , Resultado do Tratamento
11.
Braz. j. med. biol. res ; 47(3): 259-264, 03/2014. tab
Artigo em Inglês | LILACS | ID: lil-704627

RESUMO

This study evaluated whether the use of continuous positive airway pressure (CPAP) in the delivery room alters the need for mechanical ventilation and surfactant during the first 5 days of life and modifies the incidence of respiratory morbidity and mortality during the hospital stay. The study was a multicenter randomized clinical trial conducted in five public university hospitals in Brazil, from June 2008 to December 2009. Participants were 197 infants with birth weight of 1000-1500 g and without major birth defects. They were treated according to the guidelines of the American Academy of Pediatrics (APP). Infants not intubated or extubated less than 15 min after birth were randomized for two treatments, routine or CPAP, and were followed until hospital discharge. The routine (n=99) and CPAP (n=98) infants studied presented no statistically significant differences regarding birth characteristics, complications during the prenatal period, the need for mechanical ventilation during the first 5 days of life (19.2 vs 23.4%, P=0.50), use of surfactant (18.2 vs 17.3% P=0.92), or respiratory morbidity and mortality until discharge. The CPAP group required a greater number of doses of surfactant (1.5 vs 1.0, P=0.02). When CPAP was applied to the routine group, it was installed within a median time of 30 min. We found that CPAP applied less than 15 min after birth was not able to reduce the need for ventilator support and was associated with a higher number of doses of surfactant when compared to CPAP applied as clinically indicated within a median time of 30 min.


Assuntos
Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Pressão Positiva Contínua nas Vias Aéreas , Salas de Parto , Recém-Nascido de muito Baixo Peso/fisiologia , Surfactantes Pulmonares/uso terapêutico , Síndrome do Desconforto Respiratório do Recém-Nascido/prevenção & controle , Extubação , Brasil , Mortalidade Hospitalar , Hipertensão/diagnóstico , Intubação Intratraqueal , Tempo de Internação , Bem-Estar Materno , Diagnóstico Pré-Natal , Respiração Artificial
12.
Braz J Med Biol Res ; 47(3): 259-64, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24554040

RESUMO

This study evaluated whether the use of continuous positive airway pressure (CPAP) in the delivery room alters the need for mechanical ventilation and surfactant during the first 5 days of life and modifies the incidence of respiratory morbidity and mortality during the hospital stay. The study was a multicenter randomized clinical trial conducted in five public university hospitals in Brazil, from June 2008 to December 2009. Participants were 197 infants with birth weight of 1000-1500 g and without major birth defects. They were treated according to the guidelines of the American Academy of Pediatrics (APP). Infants not intubated or extubated less than 15 min after birth were randomized for two treatments, routine or CPAP, and were followed until hospital discharge. The routine (n=99) and CPAP (n=98) infants studied presented no statistically significant differences regarding birth characteristics, complications during the prenatal period, the need for mechanical ventilation during the first 5 days of life (19.2 vs 23.4%, P=0.50), use of surfactant (18.2 vs 17.3% P=0.92), or respiratory morbidity and mortality until discharge. The CPAP group required a greater number of doses of surfactant (1.5 vs 1.0, P=0.02). When CPAP was applied to the routine group, it was installed within a median time of 30 min. We found that CPAP applied less than 15 min after birth was not able to reduce the need for ventilator support and was associated with a higher number of doses of surfactant when compared to CPAP applied as clinically indicated within a median time of 30 min.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Salas de Parto , Recém-Nascido de muito Baixo Peso/fisiologia , Surfactantes Pulmonares/uso terapêutico , Síndrome do Desconforto Respiratório do Recém-Nascido/prevenção & controle , Extubação , Brasil , Feminino , Mortalidade Hospitalar , Humanos , Hipertensão/diagnóstico , Recém-Nascido , Intubação Intratraqueal , Tempo de Internação , Masculino , Bem-Estar Materno , Gravidez , Diagnóstico Pré-Natal , Respiração Artificial/estatística & dados numéricos
13.
Food Chem Toxicol ; 60: 218-37, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23907020

RESUMO

Mycotoxins are abiotic hazards produced by certain fungi that can grow on a variety of crops. Consequently, their prevalence in plant raw materials may be relatively high. The concentration of mycotoxins in finished products is usually lower than in raw materials. In this review, occurrence and toxicology of the main mycotoxins are summarised. Furthermore, methodological approaches for exposure assessment are described. Existing exposure assessments, both through contamination and consumption data and biomarkers of exposure, for the main mycotoxins are also discussed.


Assuntos
Exposição Ambiental/análise , Contaminação de Alimentos/análise , Micotoxinas/toxicidade , Aflatoxinas/análise , Aflatoxinas/toxicidade , Animais , Qualidade de Produtos para o Consumidor , Microbiologia de Alimentos , Fumonisinas/análise , Fumonisinas/toxicidade , Humanos , Ocratoxinas/análise , Ocratoxinas/toxicidade , Tricotecenos/análise , Tricotecenos/toxicidade , Zearalenona/análise , Zearalenona/toxicidade
14.
Food Chem Toxicol ; 51: 188-93, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23046858

RESUMO

The main objective of this study was to assess the exposure of Catalonian (Spain) population to AFs. Thus, two sub-objectives were considered: (1) to assess the occurrence of AFs in food marketed in Catalonia, and (2) to assess the consumption of those foods susceptible to AFs contamination by Catalonian population. AFs were analysed in a total of 603 samples considering special commodities as free-gluten, ethnic or baby foods. Analytical method consisted of an extraction and clean-up of aflatoxins step using immunoaffinity columns, and determination by HPLC with post-column photochemical derivatization and fluorescence detection. Food dietary intake was assessed using a food frequency questionnaire, administered to 1387 individuals by trained interviewers. Contamination and consumption raw datasets were combined by means of a direct method and a stochastic method, building the pseudo-parametric bootstrap confidence intervals of the main outputs. Margins of exposure (MoE) and cancer incidence were estimated for the different collectives. The highest percentages of positive samples were found in red pepper, pistachios and peanuts. Considering our results, the most exposed group was the celiac sufferer collective followed by the adolescents; however health concern should not be expected in the population groups.


Assuntos
Aflatoxinas/análise , Aflatoxinas/toxicidade , Contaminação de Alimentos/análise , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão/métodos , Dieta , Exposição Ambiental , Feminino , Humanos , Lactente , Alimentos Infantis , Masculino , Pessoa de Meia-Idade , Medição de Risco , Espanha , Inquéritos e Questionários , Adulto Jovem
15.
Artigo em Inglês | MEDLINE | ID: mdl-22394208

RESUMO

Ochratoxin A (OTA) was analysed in composite samples of cereal-based baby foods, beer, breakfast cereals (corn- and rice and wheat-based), loaf bread, peanuts and pistachios. Foodstuffs were collected in hypermarkets and supermarkets from 12 cities in the Spanish region of Catalonia, and composite samples were prepared for analysis involving liquid-liquid extraction, followed by immunoaffinity column clean-up and HPLC with fluorescence detection. Consumption data for the selected foodstuffs were collected by means of a food-frequency questionnaire. The studied population was grouped by age in infants, children, adolescents and adults; and exposure to OTA through the specified foodstuffs, and through wine and coffee, was assessed. Exposure assessment was done through deterministic and probabilistic modelling of the contamination and consumption data. OTA occurrence and mean of positive samples (ng g(-1) or ng ml(-1), for beer) were the following: 8.7% and 0.233 in baby foods; 88.7% and 0.022 in beer; 2.8% and 0.728 in corn-based breakfast cereals; 25% and 0.293 in wheat-based breakfast cereals; 12.9% and 0.283 in loaf bread; 41.7% and 0.241 in peanuts; and 2.9% and 0.228 in pistachios. The median estimated daily intake of OTA through the foodstuffs by each age group were below the latest provisional tolerable daily intakes (PTDIs) of 17 and 14 ng kg(-1) bw day(-1) recommended by the European Food Safety Authority (EFSA) in 2006 and the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in 2007, respectively, ranging from 1% and 2% of those values in adolescents and children, to 3% and 11% in adults and infants.


Assuntos
Bebidas/análise , Dieta , Grão Comestível/química , Exposição Ambiental , Nozes/química , Ocratoxinas/análise , Adolescente , Adulto , Cerveja/análise , Criança , Pré-Escolar , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Café/química , Feminino , Humanos , Lactente , Limite de Detecção , Masculino , Probabilidade , Espanha , Vinho/análise , Adulto Jovem
16.
Food Chem Toxicol ; 50(3-4): 511-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22261462

RESUMO

HT-2 toxin (HT2) and T-2 toxin (T2) are mycotoxins produced in several cereals by species of Fusarium. The aim of the present study was to assess the exposure of Catalonian population to the combined mycotoxins T2 and HT2. Three different approaches were considered to handle the left censored data: (1) a substitution method, (2) a parametric method using the maximum likelihood estimation (MLE) and (3) a non-parametric method using the Kaplan-Meier (KM) estimator. Raw contamination data was provided by a large survey conducted in this region, in addition to the raw consumption data from a nutritional study specifically designed to assess the dietary intake of the main foodstuffs related to T2 and HT2 contamination for all population age groups. Contamination and consumption data were combined by simulation using a stochastic method. Accuracy and reliability of the statistic estimates were assessed building the related confidence intervals using a pseudo-parametric bootstrap method. Considering the results from the present study, the most exposed group population to the toxin T2 and HT2 should be expected to be the children.


Assuntos
Exposição Ambiental , Micotoxinas/toxicidade , Fusarium/química , Humanos , Reprodutibilidade dos Testes , Espanha , Processos Estocásticos
17.
Artigo em Inglês | MEDLINE | ID: mdl-22273497

RESUMO

Fumonisin B1 (FB1) and B2 (FB2) are mycotoxins produced by Fusarium verticillioides and F. proliferatum and common contaminants of cereal crops. The objectives of this study were to (1) study the occurrence of fumonisins in Catalonia (north-eastern region of Spain) and (2) assess the exposure of the Catalonian population to these mycotoxins. Contamination data was provided by a wide survey where 928 individual samples were pooled to analyse 370 composite samples. Fumonisins were extracted and purified using immunoaffinity columns and determined by HPLC with fluorescence detection. The raw consumption data came from a nutritional study specifically designed to assess the dietary intake of the main foodstuffs related to fumonisin contamination for all population age groups. In addition, two specific groups were selected with respect to maize consumption: immigrants and celiac sufferers. Contamination and consumption data were combined by simulation using an essentially parametric-parametric (P-P) method. The P-P method draws sampling values from distribution functions fitted to consumption and contamination datasets. Moreover, to quantify the accuracy and reliability of the statistical estimates, we built related confidence intervals using a Pseudo-Parametric bootstrap method. The results of this study show that fumonisins are commonly found in some commodities on the Catalonian market, such as beer, corn snacks and ethnic foods; however, the values were well below the permitted maximum EU levels. The most exposed group were infants followed by immigrants but, in all cases, they were below the TDI of 2 µg/kg bw/day.


Assuntos
Carcinógenos Ambientais/administração & dosagem , Carcinógenos Ambientais/análise , Dieta/efeitos adversos , Contaminação de Alimentos , Fumonisinas/administração & dosagem , Fumonisinas/análise , Adolescente , Adulto , Idoso , Cerveja/efeitos adversos , Cerveja/análise , Carcinógenos Ambientais/toxicidade , Doença Celíaca/dietoterapia , Criança , Dieta/etnologia , Dieta Livre de Glúten/efeitos adversos , Emigrantes e Imigrantes , Fast Foods/efeitos adversos , Fast Foods/análise , Fumonisinas/toxicidade , Humanos , Lactente , Alimentos Infantis/efeitos adversos , Alimentos Infantis/análise , Medição de Risco , Sementes/efeitos adversos , Sementes/química , Espanha , Zea mays/efeitos adversos , Zea mays/química
18.
Food Chem Toxicol ; 50(3-4): 835-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22155269

RESUMO

The objectives of this study were to assess the occurrence of zearalenone (ZEA) in food in Catalonia (Spain); to assess the consumption of the main food items contaminated with ZEA; and finally, to estimate the dietary exposure of the Catalonian population to the mycotoxin. Therefore 1187 samples were collected from the Catalonian market and pooled to obtain 485 analytical samples (composites) of the commodities most susceptible to ZEA contamination and commonly consumed in the region. Extraction and clean-up was performed using immunoaffinity columns and ZEA was detected and quantified by high performance liquid chromatography (HPLC) and fluorescence detection. A specific food frequency questionnaire (FFQ) was administered to 1264 individuals by trained interviewers to estimate the consumption of the relevant foods. The results showed that the occurrence of ZEA in food marketed in Catalonia was infrequent. Sliced bread, corn snacks and sweet corn were the commodities where it was most often present. In considering the contamination levels and food consumption estimates, the dietary intake of ZEA by the Catalonian population was estimated to be considerably lower than the temporary tolerable daily intake (TDI) of 200 ng ZEA kg(-1) bw day(-1).


Assuntos
Exposição Ambiental , Estrogênios/toxicidade , Micotoxinas/toxicidade , Zearalenona/toxicidade , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Estrogênios/análise , Contaminação de Alimentos , Humanos , Micotoxinas/análise , Espanha , Espectrometria de Fluorescência , Zearalenona/análise
19.
Clin Transl Oncol ; 13(12): 855-61, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22126728

RESUMO

Management of muscle-invasive bladder cancer (MIBC) has changed little in the last twenty years. The gold standard treatment is still cystectomy, but it has a significant negative impact on quality of life. Bladder-preservation strategies can be used in some cases but patient selection for this approach remains unclear. New chemotherapy and biologic agents in combination with surgery or radiotherapy could improve results and these possibilities are currently under investigation.


Assuntos
Neoplasias Musculares/terapia , Neoplasias da Bexiga Urinária/terapia , Terapia Combinada , Humanos , Invasividade Neoplásica
20.
Artigo em Inglês | MEDLINE | ID: mdl-21644119

RESUMO

Fumonisins occur mainly in maize and they produce alterations on sphingolipid metabolism, unbalancing the sphinganine (Sa)/sphingosine (So) ratio. This alteration has been proposed as a biomarker of fumonisin exposure. The objective of this study was to establish the urinary and plasmatic levels of Sa, So as well as the ratio Sa/So from a sample of the Catalonian (Spain) population exposed to fumonisins at low levels. Firstly, plasma and urinary Sa and So levels and the ratio Sa/So were compared between two population groups, and later urinary Sa and So levels from corn food consumers and a control group were monitored for 2 weeks under controlled intake of corn foods. Sa and So levels were determined in urine and blood samples using validated methods using HPLC with fluorescence detection. Significant differences were not found in urine samples when Sa/So ratios were compared from corn food consumers and non-consumers, while significant differences were found in urine and plasma samples, but evidence of the mechanism of action of fumonisins was not apparent. Through a time-course study we have narrowed down the day in which the maximum alteration of Sa/So ratio should be expected in humans. This paper reports some useful information to improve the design of studies to validate the ratio Sa/So as a possible biomarker of fumonisin exposure.


Assuntos
Esfingosina/análogos & derivados , Esfingosina/análise , Cromatografia Líquida de Alta Pressão , Humanos , Espanha , Espectrometria de Fluorescência , Esfingosina/sangue , Esfingosina/urina
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