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1.
Environ Sci Eur ; 33(1): 33, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33828936

RESUMO

BACKGROUND: Low maximum and action levels set by the European Union for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in pig meat (pork) have led to a demand for reliable and cost-effective bioanalytical screening methods implemented upstream of gas chromatography/high-resolution mass spectrometry confirmatory technology, that can detect low levels of contamination in EU-regulated foods with quick turn-around times. RESULTS: Based on the Chemically Activated LUciferase gene eXpression (CALUX) bioassay, extraction and clean-up steps were optimized for recovery and reproducibility within working ranges significantly lower than in current bioassays. A highly sensitive "3rd generation" recombinant rat hepatoma cell line (H4L7.5c2) containing 20 dioxin responsive elements was exposed to pork sample extracts, and their PCDD/Fs and DL-PCBs levels were evaluated by measuring luciferase activity. The method was validated according to the provisions of Commission Regulation (EU) 2017/644 of 5 April 2017 with spiking experiments performed selectively for PCDD/Fs and DL-PCBs and individual calibration for PCDD/Fs, DL-PCBs and the calculated sum of PCDD/Fs and DL-PCBs. The resulting performance parameters met all legal specifications as confirmed by re-calibration using authentic samples. Cut-off concentrations for assessing compliance with low maximum levels and action levels set for PCDD/Fs and DL-PCBs within a range of 0.50-1.25 pg WHO-TEQ/g fat were derived, ensuring low rates of false-compliant results (ß-error < 1%) and keeping the rate of false-noncompliant results well under control (α-error < 12%). CONCLUSIONS: We present a fast and efficient bioanalytical routine method validated according to the European Union's legal requirements on the basis of authentic samples, allowing the analyst to reliably identify pork samples and any other EU-regulated foods of animal origin suspected to be noncompliant with a high level of performance and turn-around times of 52 h. This was facilitated in particular by a quick and efficient extraction step followed by selective clean-up, use of a highly sensitive "3rd generation" H4L7.5c2 recombinant rat hepatoma cell CALUX bioassay, and optimized assay performance with improved calibrator precision and reduced lack-of-fit errors. New restrictions are proposed for the calibrator bias and the unspecific background contribution to reportable results. The procedure can utilize comparably small sample amounts and allows an annual throughput of 840-1000 samples per lab technician. The described bioanalytical method contributes to the European Commission's objective of generating accurate and reproducible analytical results according to Commission Regulation (EU) 2017/644 across the European Union.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33614386

RESUMO

BACKGROUND: Persistent organic pollutants (POPs) such as dioxins, dioxin-like chemicals and non-dioxin-like PCBs causing adverse effects to human health bio-accumulate through the food web due to their affinity for adipose tissues. Foods of animal origin are therefore the main contributors to human dietary exposure. The European Union's (EU) food safety policy requires checking of a wide range of samples for compliance with legal limits on a regular basis. Several methods of varying efficiency are applied by official control laboratories for extraction of the different classes of lipids and associated POPs, bound to animal tissue and animal products in varying degrees, sometimes leading to discrepancies especially in fresh weight based analytical results. RESULTS: Starting from Smedes' lipid extraction from marine tissue, we optimized the extraction efficiency for both lipids and lipophilic pollutants, abandoning the time-consuming centrifugation step. The resulting modified Smedes extraction (MSE) method was validated based on multiple analyses of a large number of real world samples, matrix calibration and performance assessment in proficiency testing utilizing both instrumental and bioanalytical methodologies. Intermediate precision in 12 different foods was below 3% in chicken eggs, egg powder, animal fat, fish, fish oil, poultry, whole milk, milk fat and milk powder, and below 5% in bovine meat, liver, and infant food. In comparison to Twisselmann hot extraction, results presented here show an increased efficiency of MSE by +25% for bovine liver, +14% for chicken eggs, +13% for poultry meat, +12% for fish, 8% for bovine meat, and 6% for infant food. CONCLUSIONS: For the first time, a fast and reliable routine method is available that enables the analyst to reproducibly extract "total" lipids from any EU-regulated food sample of animal origin within 6 to 8 minutes. Increased efficiency translates into a considerable increase in both lipid and wet weight-based analytical results measured for associated POPs, reducing the risk of false non-compliant results. Compared to a 4 hour Twisselmann extraction, the extraction of 1000 samples using MSE would result in annual savings of about 250 hours or 32 working days. Our MSE procedure contributes to the European Commission's objective of harmonising analytical results across the EU generated according to Commission Regulation (EU) 2017/644.

3.
J Cancer Res Clin Oncol ; 144(10): 1921-1932, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30076481

RESUMO

PURPOSE: Lung cancer is highly prevalent and has an especially poor prognosis. Thus, new diagnostic and therapeutic targets are necessary. Two potential targets are somatostatin receptors (SST), which are overexpressed in well-differentiated neuroendocrine neoplasms, and the chemokine receptor CXCR4, which is present mainly in highly proliferative and advanced tumours. Although their expression is relatively well characterized in small cell lung cancer (SCLC), in non-small cell lung cancer (NSCLC), data on SST and CXCR4 expression are scarce and contradictory. METHODS: We comparatively evaluated 83 tumour samples from a total of 57 lung cancer patients, of which 22 had adenocarcinoma (ADC), 21 had squamous cell carcinoma (SQC), and 15 had SCLC. Samples were evaluated for SST and CXCR4 expression using immunohistochemistry with well-characterized rabbit monoclonal antibodies. RESULTS: In the samples investigated, the most prominently expressed receptors were CXCR4 and SST5. Specifically, CXCR4 was detected with high expression intensity in more than 60% of ADC samples, about 90% of SQC, and 100% of SCLC. SST5 was present in about 75% of ADC and SQC samples and in more than 90% of SCLC. Although not noticeably expressed in ADC and SQC samples, SST2 was detected in 50% of SCLC cases, with a subset of patients displaying exceptionally high expression. The comparison of the three tumour entities revealed that SCLC samples had higher SST2, SST5, and CXCR4 expression, but lower SST3 and SST1 relative to ADC or SQC samples. CONCLUSION: CXCR4 may be a promising target for diagnostics and therapy in both SCLC and NSCLC.


Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Pulmonares/metabolismo , Receptores CXCR4/metabolismo , Carcinoma de Pequenas Células do Pulmão/metabolismo , Somatostatina/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Transdução de Sinais , Carcinoma de Pequenas Células do Pulmão/patologia , Carcinoma de Pequenas Células do Pulmão/cirurgia , Taxa de Sobrevida
4.
Arq. int. otorrinolaringol. (Impr.) ; 15(2): 249-255, abr.-jun. 2011. ilus, tab
Artigo em Inglês, Português | LILACS | ID: lil-594674

RESUMO

Introdução: A Prótese Implantável de Condução Óssea (BAHA) consiste em uma excelente opção na reabilitação auditiva de pacientes com perda auditiva condutiva e mista uni ou bilateral, e sensorioneural unilateral. Tem sido uma alternativa vantajosa sobre os aparelhos de condução óssea convencionais e os aparelhos de amplificação sonora individuais (AASI) quando o uso dos mesmos fica impossibilitado pela presença de otite externa crônica de difícil controle clínico. Objetivo: Apresentar o primeiro caso de BAHA realizado no Brasil, após a autorização da ANVISA, para a reabilitação da perda auditiva mista com episódios de otite externa crônica. Método: Paciente do sexo feminino, 50 anos, com perda auditiva de grau moderado à direita e severo à esquerda, zumbido bilateral, decorrente de otosclerose, submetida a quatro cirurgias de estapedotomia e com impossibilidade de uso de AASI devido a otorreia e otalgia bilateral. A avaliação médica e audiológica indicaram o benefício do BAHA. Realizada a cirurgia e implantação do sistema BAHA, a paciente apresentou melhora significativa nos limiares audiométricos, na percepção e discriminação da fala, além de relatar extrema satisfação relacionada ao fator estético. Comentários Finais: O processo cirúrgico do BAHA é seguro, simples e rápido, proporcionando excelentes resultados audiológicos e alto grau de satisfação por parte dos pacientes.


Introduction: The implantable prosthesis of osseous conduction (BAHA) is deemed to be an excellent option in the auditory rehabilitation of patients with conductive and mixed hearing loss, unilaterally or bilaterally, and unilateral sensorineural hearing loss. It has been a good advantage over the conservative bone conduction apparatus and those of individual sound-amplifier apparatus (ISAA), when their usage becomes unfeasible because of chronic otitis externa, which has a hard clinic control. Objective: To introduce the first BAHA case performed in Brazil, as duly authorized by ANVISA (National Agency for Sanitary Surveillance), to rehabilitate the mixed hearing loss with occurrences of chronic otitis externa. Method: 50-year-old female patient with right-ear moderate and left-ear severe hearing loss, bilateral tinnitus derived from otosclerosis, was submitted to 04 surgeries of stapedotomy and unable to use ISAA as a result of otorrhea and bilateral otalgia. The medical and audiological evaluation indicated the benefit of using BAHA. Having surgery been performed and BAHA implemented, the patient showed a significant improvement in audiometric thresholds, speech perception and distinction, as well as she declared to be extremely satisfied with the esthetic factor. Final commentaries: BAHA surgical process is safe, simple and swift, thus providing excellent audiological results and a higher degree of satisfaction to patients.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Próteses e Implantes , Audiometria , Condução Óssea , Otite Externa/cirurgia , Perda Auditiva Condutiva/reabilitação , Procedimentos Cirúrgicos Otológicos
5.
Eur J Nutr ; 42(4): 217-23, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12923653

RESUMO

Anthocyanins are receiving renewed attention for their positive health attributes. High intakes and an adequate absorption rate of anthocyanins are necessary for efficient protection, though other dietary agents might influence absorption efficacy. The aim of this study was to investigate intestinal handling of luminally administered cyanidin-3-glucoside in the absence and presence of ethanol in an isolated preparation of luminally and vascularly perfused rat small intestine. A synthetic perfusate free from blood components was used as vascular medium, with a perfluorocarbon as the oxygen carrier. Luminal media consisted of a bicarbonate buffered sodium chloride solution in water or in water/ethanol (95/5), spiked with cyanidin-3-glucoside. Absorption rate of cyanidin-3-glucoside was 4.3% +/- 3.2 (n=5). Ethanol (5 %) had no significant influence on absorption rate (2.9% +/- 1.8, n=5). Irrespective of the presence of ethanol, the majority of the absorbed cyanidin-3-glucoside appeared unchanged, besides some cyanidin-3-glucoside-conjugate.


Assuntos
Antocianinas/farmacocinética , Etanol/farmacologia , Glucosídeos/farmacocinética , Absorção Intestinal , Intestino Delgado/metabolismo , Animais , Antocianinas/metabolismo , Cromatografia Líquida de Alta Pressão , Glucosídeos/metabolismo , Técnicas In Vitro , Absorção Intestinal/efeitos dos fármacos , Intestino Delgado/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
6.
Int J Vitam Nutr Res ; 73(2): 152-9, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12747223

RESUMO

Phenolic compounds are secondary plant metabolites which have long been associated with flavor and color characteristics of fruits and vegetables. These phenolic compounds attract great interest due to their postulated health protecting properties. However, adequate intakes and absorption rate of phenolic compounds are necessary for these beneficial effects. Until now, little is known about alterations of phenolic compounds content by the cooking process. In the present study, the influence of different volumes of cooking water on the amount of selected phenolic marker compounds resting in the vegetables was assessed. In zucchini, rutin was quantified as a marker for flavonoid glycosides. Chlorogenic acid, representative of phenolic acids was analyzed in carrots. In beans, rutin and quercitrin, both belonging to flavonoid glycosides, were investigated. In potatoes, chlorogenic and caffeic acid were determined. The cooking of zucchini, beans and carrots with smaller amounts of water resulted in significant higher content of phenolic phytochemicals in the vegetables compared to cooking with larger water volumes. For potatoes, which showed great variations in content of phenolic acids after cooking, no significant differences in phenolic acids was observed. It can be concluded from these observations, that real intakes of phenolic compounds from cooked vegetables are lower and that the amounts consumed are therefore overestimated.


Assuntos
Culinária/métodos , Fenóis/análise , Quercetina/análogos & derivados , Verduras/química , Ácidos Cafeicos/análise , Ácido Clorogênico/análise , Cromatografia Líquida de Alta Pressão , Cucurbita/química , Daucus carota/química , Fabaceae/química , Temperatura Alta , Quercetina/análise , Rutina/análise , Solanum tuberosum/química , Água
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