Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Más filtros

Banco de datos
Tipo del documento
Asunto de la revista
Intervalo de año de publicación
1.
Lab Invest ; 92(3): 345-61, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22157720

RESUMEN

Granulomatous inflammations, characterized by the presence of activated macrophages (MAs) forming epithelioid cell (EPC) clusters, are usually easy to recognize. However, in ambiguous cases the use of a MA marker that expresses selectively in EPCs may be needed. Here, we report that carboxypeptidase-M (CPM), a MA-differentiation marker, is preferentially induced in EPCs of all granuloma types studied, but not in resting MAs. As CPM is not expressed constitutively in MAs, this allows utilization of CPM-immunohistochemistry in diagnostics of minute granuloma detection when dense non-granulomatous MAs are also present. Despite this rule, hardly any detectable CPM was found in advanced/active tubercle caseous disease, albeit in early tuberculosis granuloma, MAs still expressed CPM. Indeed, in vitro both the CPM-protein and -mRNA became downregulated when MAs were infected with live mycobacteria. In vitro, MA-CPM transcript is neither induced remarkably by interferon-γ, known to cause classical MA activation, nor by IL-4, an alternative MA activator. Instead, CPM is selectively expressed in lipid-laden MAs, including the foam cells of atherosclerotic plaques, xanthomatous lesions and lipid pneumonias. By using serum, rich in lipids, and low-density lipoprotein (LDL) or VLDL, CPM upregulation could be reproduced in vitro in monocyte-derived MAs both at transcriptional and protein levels, and the increase is repressed under lipid-depleted conditions. The microarray analyses support the notion that CPM induction correlates with a robust progressive increase in CPM gene expression during monocyte to MA maturation and dendritic cell (DC) differentiation mediated by granulocyte-MA-colony-stimulating factor+IL-4. M-CSF alone also induced CPM. These results collectively indicate that CPM upregulation in MAs is preferentially associated with increased lipid uptake, and exposure to CSF, features of EPCs, also. Therefore, CPM-immunohistochemistry is useful for granuloma and foam MA detections in tissue sections. Furthermore, the present data offer CPM for the first time to be a novel marker and cellular player in lipid uptake and/or metabolism of MAs by promoting foam cell formation.


Asunto(s)
Células Epitelioides/enzimología , Células Espumosas/enzimología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Granuloma/metabolismo , Metaloendopeptidasas/metabolismo , Biomarcadores/metabolismo , Diferenciación Celular , Células Dendríticas/citología , Células Dendríticas/metabolismo , Proteínas Ligadas a GPI/metabolismo , Humanos , Inmunohistoquímica , Interleucina-4/metabolismo , Metabolismo de los Lípidos , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Activación Transcripcional , Regulación hacia Arriba
2.
Food Chem Toxicol ; 170: 113493, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36326503

RESUMEN

The current study assessed the risk posed to Iranian consumers by oral exposure to a mixture of 20 pesticides and six metals in 96 fruit juice (FJ) samples (3 batches × 4 brands × 8 types of FJs) collected from Iran market. Concentrations of metals and pesticides in FJs were quantified by inductively coupled plasma-optical emission spectrometry (ICP-OES) and chromatography-mass spectrometry (GC-MS), respectively. The mean concentration of all pesticides was below the maximum residue limits (MRLs) set by the European Union (EU). The calculated target hazard quotients (THQs) and total hazard index (HI) were <1.0 for all pesticides residue, indicating no risk. For the carcinogenic metals (As, Ni, and Pb), estimated incremental lifetime cancer risks (ILCRs) at the 50th and 95th centiles were respectively 4.25 × 10-5 and 5.30 × 10-5 (for As), 2.85 × 10-5 and 3.71 × 10-5 (for Ni), and 2.84 × 10-8, and 3.97 × 10-8 (for Pb), indicating no risk. At the 50th and 95th centiles, HI for non-carcinogenic metals (Cd, Hg, and Cr) was <1.0, indicating no risk. Based on sensitivity analyses of the input variables, the concentration of metals and pesticides, and the FJs ingestion rate had significant influential impacts on the calculated THQ and HI.


Asunto(s)
Metales Pesados , Plaguicidas , Metales Pesados/toxicidad , Metales Pesados/análisis , Irán , Jugos de Frutas y Vegetales/análisis , Plaguicidas/toxicidad , Plaguicidas/análisis , Plomo/análisis , Medición de Riesgo , Monitoreo del Ambiente
3.
Food Chem Toxicol ; 140: 111262, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32198030

RESUMEN

Pesticides are widely used in agriculture and their proven high toxicity makes the need of monitoring their presence in food imperative. A multi residue method is applied in apples samples (81) collected from the Greek market for the monitoring of 40 analytes. Pesticides levels were evaluated by gas and liquid chromatography-mass spectrometry using a QuEChERs protocol. Risk for consumers was assessed by a newly developed methodology, employing the source related Hazard Quotient (HQs) and the adversity specific Hazard Index (HIA). The 84% of the apple's samples were positive for at least one pesticide, 21% for one pesticide, 55.6% for two to four pesticide residues and 7.4% for more than 4 pesticide residues. The most frequently detected compound was carbendazim (45.7%) followed by chlorpyrifos (44.4.0%). The mean detected concentration levels varied from 0.169 ppm (fluopyram) to 0.005 ppm (triazophos). 19 of the 40 investigated pesticides were not detected in any apple sample. For all individual pesticides, the source related Hazard Quotient (HQs) was <1 indicating no risk. HIA, resulting from the sum of all HQs was found HIA < 1 in nine out of ten toxicity groups, except to the neurotoxicity group, which presented HIA 2.258, indicating moderate risk.


Asunto(s)
Contaminación de Alimentos/análisis , Fungicidas Industriales/análisis , Insecticidas/análisis , Malus/química , Residuos de Plaguicidas/análisis , Cromatografía Liquida/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Grecia , Medición de Riesgo , Espectrometría de Masas en Tándem/métodos
4.
Toxicol Rep ; 7: 1057-1065, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32923372

RESUMEN

Greek fermentation and distillation industries produce traditional spirit beverages, such as tsipouro and tsikoudia, consumed both in bottles and bulk quantities by the general population or tourists. The same spirits are also produced by individuals at home since previous centuries, as a part of the local culture but mainly due to the Greek agricultural sector unique characteristics (small cultivation areas with great number of farmers). In this study, the concentrations of carcinogenic compounds: ethanol and acetaldehyde; and noncarcinogenic: higher alcohols (1-propanol, isobutanol, and isoamyl alcohol), esters (ethyl acetate), and methanol were measured to estimate the potential cancer risk and daily intake of these compounds. The margin of exposure (MOE) of carcinogenic compounds was found to be less than 500 (mean value), well below the toxic threshold of 10,000, above which there is not public concern, as suggested by the European Food Safety Authority. Additionally, through risk assessment of noncarcinogenic compounds, we identified two specific compounds in-bulk spirits (produced by individuals), namely ethyl acetate and isobutanol, with health risk index (HRI) greater than 1 (indicating a possibility to induce side effects by consumption of high amounts). Our results indicate that bottled spirits, which are produced in a controlled environment (alcohol industries), showed higher human safety level in terms of both carcinogenic and noncarcinogenic risk assessment studies, comparing to bulk beverages produced by individuals (with out strict regulations).

5.
J Cancer Res Clin Oncol ; 134(4): 439-51, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17922141

RESUMEN

PURPOSE: Carboxypeptidase-M (CPM) is a membrane-bound peptidase that metabolizes peptides, and is present in pneumocytes. CPM hydrolyses the C-terminal arginine of epidermal growth factor (EGF) resulting in des-Arg53-EGF which binds to the EGF receptor (EGFR) with an equal or greater affinity than native EGF. Therefore, this study focused on the possible presence of CPM in human lung adenocarcinomas (ADC) and evaluated the relationship between CPM and EGFR by assessing the impact of expressions on patient clinical outcome. METHODS: This is a retrospective study of 110 patients who underwent resection of the primary tumour (92) or metastatic tissues (18) for treatment or diagnosis. Immunohistochemistry (IHC) for CPM and EGFR was made in serial sections using standard methods. RESULTS: This study demonstrates for the first time that 23.6% of ADCs express carboxypeptidase-M (26/110), mainly in membrane-bound forms. The amounts and the extent of CPM within tumours vary from low levels to obviously overexpressed forms. The immunohistochemical positivity (+) for CPM in ADCs negatively correlated with disease survival. In addition, 80% of CPM+ adenocarcinomas (21/26) showed a coexpression with EGFR suggesting a high prevalence for coexistence. The follow up data indicated a significantly shorter 5-year survival time for patients with CPM+-EGFR+ (double-positive) tumours compared to those harbouring neoplasias negative for both proteins (9.5 vs. 60.4% survivals, P < 0.001). CONCLUSION: The fact that CPM+ ADCs often co-express with EGFR suggests a functional-regulatory link between these proteins which might have therapeutical consequences. The present novel data could lead to improved IHC tests in lung adenocarcinomas for EGFR expression.


Asunto(s)
Adenocarcinoma/química , Receptores ErbB/análisis , Neoplasias Pulmonares/química , Metaloendopeptidasas/análisis , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Femenino , Proteínas Ligadas a GPI , Humanos , Inmunohistoquímica , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Estadificación de Neoplasias , Estudios Retrospectivos
6.
Environ Toxicol Pharmacol ; 61: 61-66, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29852370

RESUMEN

Iran is one of the main suppliers of pistachio for the European market accounting for over 90% of its demands; hence, efficient analytical methods are required for detection of mycotoxins contamination in pistachio kernels before exporting them. In this study, aflatoxin B1 (AFB1) and ochratoxin A (OTA) levels in five pistachio cultivars collected from four sites of Iran, were measured by HPLC. Based on the results, risk assessment for AFB1 and OTA residues was done. The highest mean concentrations of AFB1 and OTA were found in Ahmad-aghaei (4.33 and 2.19 ng/g, respectively) and Akbari (4.08 and 1.943 ng/g, respectively) cultivars from Rafsanjan, Iran. Even the highest concentrations of AFB1 and OTA in analyzed samples were lower than the corresponding maximum limits set by EU authorities. The hazard index (HI) value for consumers of Iranian pistachio is below one. It could be concluded that consumption of pistachio cultivated in these regions poses no health risk of mycotoxins exposure.


Asunto(s)
Aflatoxina B1/análisis , Contaminación de Alimentos/análisis , Nueces/química , Ocratoxinas/análisis , Pistacia , Monitoreo del Ambiente , Humanos , Irán , Medición de Riesgo
7.
Food Addit Contam Part B Surveill ; 10(2): 85-90, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27897085

RESUMEN

Bisphenol A (BPA) is one of the most common industrial chemicals and known to exert endocrine disruption activity. The aim of this study was the quantification of BPA in food stuffs on the Greek market. The applied liquid chromatography-mass spectrometry method was validated for linearity, limit of quantification, accuracy, precision and recovery. About 41.7% of the canned solid phase samples, 25.0% of the canned liquid phase samples and 43.8% of the soft drinks were positive. Mean BPA concentrations (range) were 33.4 ± 4.4 ng/g (4.90 ± 0.64-66.0 ± 8.6 ng/g) in canned solid phase, 2.70 ± 0.08 ng/ml (1.90 ± 0.06-3.50 ± 0.11 ng/ml) in canned liquid phase and 2.30 ± 0.18 ng/ml (0.40 ± 0.03-10.2 ± 0.8 ng/ml) in soft drinks. The results of this study are comparable with those reported in the literature according to which higher concentrations of BPA were detected in the solid fraction of canned food compared to their liquid fraction.


Asunto(s)
Compuestos de Bencidrilo/análisis , Bebidas Gaseosas/análisis , Disruptores Endocrinos/análisis , Alimentos en Conserva/análisis , Fenoles/análisis , Cromatografía Liquida/métodos , Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Grecia , Espectrometría de Masas/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
Food Chem Toxicol ; 107(Pt B): 565-571, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28330761

RESUMEN

The substance 4-methylimidazole (4-MEI) has raised several concerns regarding its toxicity to humans, although no harmonized classification has yet been decided. The regulatory limits for food products set by various authorities in Europe and the USA differ considerably. The purpose of the present study is to compare two liquid chromatography techniques in order to determine the levels of 4-MEI in food products from the Greek market and roughly estimate the possible exposure and relevant health risk for the consumers. A total of thirty-four samples (soft drinks, beers, balsamic vinegars, energy drinks and sauces) were collected and analyzed. The quality parameters for both analytical methodologies (linearity, accuracy, inter day precision, recovery) are presented. No detectable levels of 4-MEI are found in beers and soft drink samples, other than cola type. On the other hand, 4-MEI was detected in all cola type soft drinks (15.8-477.0 ng/ml), energy drinks (57.1%, 6.6-22.5 ng/ml) and vinegar samples (66.7%, 9.7-3034.7 ng/ml), while only one of the sauce samples was found to have a detectable level of 17.5 ng/ml 4-MEI.


Asunto(s)
Bebidas/análisis , Bebidas Gaseosas/análisis , Cromatografía Líquida de Alta Presión/métodos , Contaminación de Alimentos/análisis , Imidazoles/análisis , Ácido Acético/análisis , Bebidas/economía , Bebidas Gaseosas/economía , Contaminación de Alimentos/economía , Grecia , Humanos
9.
Food Chem Toxicol ; 75: 156-65, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25449197

RESUMEN

The occurrence of residues of DDT and its metabolites was monitored in 196 cow milk samples of various pasteurized commercial types collected from the Greek market. Residue levels were determined by GC-MS analysis. In 97.4% of the samples at least one DDT isomer or one of the DDT metabolites was detected, in levels not exceeding the maximum permitted residue level by the EU. Hazard Index for both carcinogenic and non-carcinogenic effects was estimated under two assumptions: a) using DDT concentrations from positive samples and b) imputing LOD/2 as an arbitrary concentration for negative samples. No statistically significant differences in detected or summed residue (p > 0.05) concentrations between different milk types were observed, with the exception of specific metabolites of DDT in some milk types. Exposure assessment scenarios were developed for children aged 1, 3, 5, 7 and 12 years old based on estimated body weights and daily milk consumption. Hazard Indices for non-carcinogenic effects were below 0.109 covering also carcinogenic effects according to WHO approach. The cancer risk values for carcinogenic effects according to the US EPA Cancer Benchmark Concentration approach, ranged from 0.4 to 18. For both effects the highest values were calculated for the 1- to 3-year-old age groups.


Asunto(s)
DDT/toxicidad , Exposición a Riesgos Ambientales , Contaminación de Alimentos/análisis , Leche/química , Residuos de Plaguicidas/toxicidad , Animales , Niño , Preescolar , DDT/análisis , Relación Dosis-Respuesta a Droga , Cromatografía de Gases y Espectrometría de Masas , Grecia , Humanos , Lactante , Residuos de Plaguicidas/análisis , Reproducibilidad de los Resultados , Medición de Riesgo
10.
Food Chem Toxicol ; 56: 261-5, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23439481

RESUMEN

Occurrence of aflatoxin M1 (AFM1) was determined in 196 milk samples (conventional, organic and kids milk) from the Greek market during November 2009 to June 2010. AFM1 content was analyzed using an Enzyme-Linked Immunosorbent Assay (ELISA) commercial kit. Aflatoxin M1 was detected in 46.5% of the samples. 46.5% of the samples were found positive for AFM1. The most frequent range of detection was between 5 and 10 ng/l. Based on the EU regulation only 2 milk samples presented AFM1 levels higher than the maximum residue limits. Two different scenarios were used for the determination of hazard index: (a) scenario 1 using only positive (detected AFM1) samples and (b) scenario 2 when missing values where imputed with Limit of Detection (LOD) divided by 2. Significant statistical differences between different milk categories were presented only when the results were imputed with LOD/2 values. Exposure assessment scenarios were developed for ages 1, 3, 5, 7 and 12 and their respective estimated weights and daily milk consumption. Under the worst-case scenario all milk types presented a Hazard Index (HI) less than one. The highest HI values appear in the ages of 1-3.


Asunto(s)
Aflatoxina M1/análisis , Contaminación de Alimentos/análisis , Leche/química , Animales , Niño , Preescolar , Ensayo de Inmunoadsorción Enzimática , Humanos , Lactante , Límite de Detección , Modelos Lineales , Medición de Riesgo
11.
J Comput Assist Tomogr ; 30(3): 460-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16778622

RESUMEN

PURPOSE: Quantitative evaluation of the lung parenchyma might be impaired or unreliable by use of reduced-dose CT protocols. Aim of the study was to define the threshold where reduced dose has significant impact on quantitative emphysema parameters. MATERIALS AND METHODS: Thirty patients with severe centrilobular emphysema underwent multidetector computed tomography (120 kV, 150 mAs). Original CT raw data were simulated using 10 mAs settings (10-100 SIMmAs). Quantitative analysis provided lung volume, emphysema volume, emphysema index, mean lung density, and 4 emphysema volume classes. Simulated low-dose results were compared with original acquisition. RESULTS: Emphysema index showed no clinical relevant variation down to 30 SIMmAs. The large emphysema volume class was significantly different below 50 SIMmAs. The intermediate and small classes showed an overproportional variation below 50 SIMmAs. CONCLUSIONS: Dose reduction down to 30 SIMmAs is possible for clinical routine. Settings below 50 SIMmAs significantly alter the in-detailed 3-dimensional emphysema quantification.


Asunto(s)
Enfisema/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Femenino , Humanos , Imagenología Tridimensional , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Dosis de Radiación
12.
Eur Urol ; 48(5): 739-44, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16203079

RESUMEN

OBJECTIVES: The prevalence of incidental prostatic adenocarcinoma (PCa) and its precursor, high grade intraepithelial neoplasia (HGPIN) in an autopsy series from Hungarians (Central European Caucasians) was assessed and compared to similar data from the United States and European countries. METHODS: Autopsy cases (n=139; 18-95 years) with no history of urological disease were histologically examined for prostate cancer and HGPIN. After en block removal, the prostate glands were fixed in formalin, sectioned at 3-5mm intervals and embedded in paraffin. Whole-mount serial sections were stained with Hematoxylin-eosin and examined for the presence of PCa and HGPIN. The frequency of PCa and HGPIN was compared to autopsy data obtained from other geographical areas. RESULTS: We found a 38.8% prevalence of incidental PCa with increasing age-related incidence. Both PCa and HGPIN are first detected in the 3rd decade and show a steady increase with age with respect to number of foci, tumor grade and volume. In the age group 81-95, 86.6% and 60% of men had PCa and HGPIN, respectively. CONCLUSIONS: Incidental PCa and HGPIN are very prevalent in Hungarian population, comparable with the high US and the Scandinavian epidemiological data for Caucasians.


Asunto(s)
Adenocarcinoma/epidemiología , Neoplasia Intraepitelial Prostática/epidemiología , Neoplasias de la Próstata/epidemiología , Adenocarcinoma/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Autopsia , Europa (Continente)/epidemiología , Humanos , Hungría/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Neoplasia Intraepitelial Prostática/patología , Neoplasias de la Próstata/patología , Estudios Retrospectivos , Estados Unidos/epidemiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA