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1.
Arch Environ Contam Toxicol ; 73(4): 619-630, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28631032

RESUMO

To achieve a "Good Environmental Status by 2015," as demanded by the water framework directive, monitoring programs are needed to furnish data on target compounds. In this study, a first evaluation of influents and main emissions of 3 local wastewater treatment plants (WWTP) in the Adour estuary (southwest of France) was performed for 23 pollutants (10 musk fragrances, 5 alkylphenols, and 8 organometallics), as well as receiving estuarine water from the same area. High frequency of occurrence of these compounds was found in influents samples (musks: 22-100%; alkylphenols 11-100%; organometallics 0-100%) and effluents (musks: 0-100%; alkylphenols 0-100%; organometallics 0-100%). The removal efficiencies were calculated and varied from negative values up to 98% with the lowest values for synthetic musk compounds. Temporal variability of the target compounds also was studied, and a few tendencies were observed. Estimation of the daily output of each WWTP into the estuary also showed that galaxolide, nonylphenol, monobuthyltin, and inorganic mercury were the compounds discharged into the environment at the highest concentrations. Finally, the occurrence of these compounds in estuarine waters was evaluated; most of them were present at concentrations below the limits of quantification (musks: 0.53-41.5 ng/L; alkylphenols 3.4-410 ng/L; organometallics 0.02-0.70 ng/L) suggesting a low impact in the resulting receiving waters.


Assuntos
Monitoramento Ambiental , Estuários , Compostos Organometálicos/análise , Poluentes Químicos da Água/análise , França , Eliminação de Resíduos Líquidos , Águas Residuárias/química
2.
Food Chem ; 200: 330-5, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26830596

RESUMO

This study aims at developing a method for the determination of 9 synthetic musk compounds in seafood products by combining the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method and determination by gas chromatography mass spectrometry (GC-EI-MS). Method detection limits (MDL) ranging between 0.001 and 1.94 ng g(-1) were obtained. The linearity is higher than 0.9899 in the range MDL - 100 ng g(-1) with precision below 18% and recoveries between 46% and 120% were obtained. The method was applied to quantify musk compounds in seafood products from the European southwest coast (oysters, mussels, salmon organs, glass eels). Galaxolide and Tonalide exhibited the highest concentration levels ranging between MDL - 96.4 ng g(-1) and MDL - 6.85 ng g(-1), respectively. Contamination levels observed for the two nitro musks (musk xylene and musk ketone) are significantly lower ranging between MDL - 0.6 ng g(-1) and MDL - 0.09 ng g(-1), respectively. Analysis of different organs of salmons showed higher concentrations in liver and gonad than in muscle tissues.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Alimentos Marinhos/análise , Xilenos/isolamento & purificação , Animais , Limite de Detecção
3.
J Chromatogr A ; 1340: 1-7, 2014 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-24679410

RESUMO

Large volume injection (LVI)-in port silylation coupled to gas chromatography-mass spectrometry (GC-MS) for the determination of alkylphenols (APs) in water samples applying four different extraction approaches was evaluated. Among the variables studied for in-port derivatization, vent time, cryo-focusing temperature and the ratio solvent volume/N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) volume were optimized using an experimental design approach. Regarding the extraction techniques, different approaches previously optimized in the research group were tested. On the one hand different polymeric materials were tested: silicon rod (SR), polyethersulfone (PES) and polydimethylsiloxane (PDMS), the latter in the stir-bar sorptive extraction format (SBSE-PDMS). PES was chosen among the polymeric materials due to the higher recoveries (compared with SR) and lower price (compared to PDMS in the stir-bar sorptive extraction, SBSE-PDMS). Both MASE and PES protocols were selected at this point for further method validation and application to real samples. Finally, the developed methods were validated and applied to the determination of target analytes in various aqueous environmental matrices, including estuarine water and wastewater. Acceptable repeatability in the case of MASE (5-17%) and PES (7-21%) procedures and method detection limits (MDLs, 5-123 and 28-328 ng L(-1) for PES and MASE, respectively) were obtained for most analytes. In terms of apparent recoveries in the presence of matrix, estuarine and effluent samples showed no significant matrix effect (apparent recoveries in the 73-121% for PES and 74-128% for MASE), while a stronger matrix effect was observed for influent wastewater samples (98-132% for PES and 65-156% for MASE). Both MASE and PES extractions combined with LVI-in-port derivatization-GC-MS were applied to the determination of APs in the estuary of Bilbao (Gulf of Biscay, Spain).


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Fenóis/análise , Poluentes Químicos da Água/análise , Acetamidas , Fenóis/isolamento & purificação , Microextração em Fase Sólida , Temperatura , Compostos de Trimetilsilil , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação
4.
Anal Bioanal Chem ; 406(4): 1253-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24136249

RESUMO

The aim of this work is to compare simultaneous isotope dilution analysis of organotin and organomercury compounds by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-inductively coupled plasma mass spectrometry (GC-ICP/MS) on certified bivalve samples. These samples were extracted by microwave with tetramethylammonium hydroxide (TMAH). Derivatization with both NaBEt4 and NaBPr4 was evaluated, and analytical performances were compared. Two CRM materials, BCR-710 and CRM-477, were analyzed by both techniques to verify accuracy. A mixed spike containing (201)Hg-enriched methylmercury (MeHg), (199)Hg-enriched inorganic mercury (iHg), (119)Sn-enriched monobutyltin (MBT), dibutyltin (DBT), and tributyltin (TBT) as well as homemade (116)Sn-enriched monophenyltin (MPT), diphenyltin (DPT), and triphenyltin (TPT) was used for the isotope dilution analysis of samples. The two techniques studied were compared in terms of classic analytical parameters: linearity, precision or repeatability (i.e., percent relative standard deviation, RSD%), limit of detection (LOD), and limit of quantification (LOQ), showing excellent linearity, precision below 12% for all analytes, and LOQs of 0.06-1.45 pg for GC-MS and 0.02-0.27 pg for GC-ICP/MS.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos de Metilmercúrio/análise , Compostos Orgânicos de Estanho/análise , Ostreidae/química , Animais , Alimentos Marinhos/análise
5.
Anal Chim Acta ; 773: 68-75, 2013 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-23561908

RESUMO

In this work the development and validation of a new procedure for the simultaneous determination of 9 nitro and polycyclic musk compounds: musk ambrette (MA), musk ketone (MK), musk mosken (MM), celestolide (ADBI), phantolide (AHMI), tonalide (AHTN), traseolide (ATII), cashmeran (DPMI) and galaxolide (HHCB) in environmental water samples (estuarine and wastewater) using microextraction by packed sorbent (MEPS) followed by large volume injection-gas chromatography-mass spectrometry (LVI-GC-MS) was carried out. Apart from the optimization of the different variables affecting MEPS (i.e., nature of the sorbent, nature of the solvent elution, sample load, and elution/injection volume) extraction recovery was also evaluated, not only for water samples but also for environmental water matrices such as estuarine and waste water. The use of two deuterated analogs ([(2)H3]-AHTN and [(2)H15]-MX) was successfully evaluated in order to correct matrix effect in complex environmental matrices such as influent samples from wastewater treatment plants. Method detection limits (MDLs) ranged from 5 to 25 ng L(-1), 7 to 39 ng L(-1) and 8 to 84 ng L(-1) for influent, effluent and estuarine samples, respectively. Apparent recoveries were higher than 75% for all target compounds in all the matrices studied (estuarine water and wastewater) and the precision of the method, calculated as relative standard deviation (RSD), was below 13.2% at 200 ng L(-1) concentration level and below 14.9% at low level (20 ng L(-1) for all the target analytes, except for AHTN which was set at 40 ng L(-1) and HHCB at 90 ng L(-1), due to the higher MDL values presented by those target compounds). Finally, this MEPS procedure was applied to the determination of the target analytes in water samples, including estuarine and wastewater, from two estuaries, Urdaibai (Spain) and Adour (France) and an established stir-bar sorptive extraction-liquid desorption/large volume injection-gas chromatography-mass spectrometry (SBSE-LD/LVI-GC-MS) method was performed in parallel for comparison. Results were in good agreement for all the analytes determined, except for DPMI.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Compostos Policíclicos/análise , Poluentes Químicos da Água/análise , Adsorção , Benzopiranos/análise , Benzopiranos/isolamento & purificação , Dinitrobenzenos/análise , Dinitrobenzenos/isolamento & purificação , Indanos/análise , Indanos/isolamento & purificação , Compostos Policíclicos/isolamento & purificação , Microextração em Fase Sólida , Temperatura , Tetra-Hidronaftalenos/análise , Tetra-Hidronaftalenos/isolamento & purificação , Eliminação de Resíduos Líquidos , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Xilenos/análise , Xilenos/isolamento & purificação
6.
Ann Oncol ; 22(5): 1094-1101, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21084429

RESUMO

BACKGROUND: Safety and efficacy of gemcitabine plus docetaxel (GD) and capecitabine plus docetaxel (CD) were compared in patients with metastatic breast cancer, where the alternate crossover monotherapy (GD→C or CD→G) was predetermined. PATIENTS AND METHODS: Patients were randomly assigned to 3-week cycles of either gemcitabine 1000 mg/m(2) on days 1 and 8 plus docetaxel 75 mg/m(2) on day 1 or capecitabine 1000 mg/m(2) twice daily on days 1-14 plus docetaxel 75 mg/m(2) day 1. Upon progression, patients received crossover monotherapy. Primary end point was time to progression (TtP). Secondary end points evaluated overall response rate (ORR), overall survival (OS), and adverse events (AEs). RESULTS: Despite over-accrual of 475 patients, the trial matured with only 324 of 385 planned TtP events due to patient discontinuations. Human epidermal growth factor receptor 2 status was not captured in this study. More CD patients (28%) discontinued due to AEs than GD patients (18.0%, P = 0.009). TtP [hazard ratio (HR) = 1.101, 95% confidence interval (CI) 0.885-1.370, P = 0.387] and OS (HR = 1.031, 95% CI 0.830-1.280, P = 0.785) were not significantly different comparing GD and CD. ORR was not statistically different (P = 0.239) comparing GD (72 of 207, 34.8%) and CD (78 of 191, 40.8%). TtP, OS, and ORR were not significantly different comparing crossover groups. GD caused greater fatigue, hepatotoxicity, neutropenia, and thrombocytopenia but not febrile neutropenia; CD caused more hand-foot syndrome, gastrointestinal toxicity, and mucositis. CONCLUSIONS: GD and CD produced similar efficacy and toxicity profiles consistent with prior clinical experience.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Capecitabina , Estudos Cross-Over , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Docetaxel , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Metástase Neoplásica , Taxoides/administração & dosagem , Gencitabina
8.
Med Mycol ; 44(6): 505-14, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16966167

RESUMO

Mice genetically selected for high (H) and low (L) antibody production (HIV-A and LIV-A) were used in an experimental model of paracoccidioidomycosis. In a previous work, it was observed that male HIV-A animals were more susceptible to the infection due to adrenal gland damage. Male HIV-A and LIV-A animals were intravenously inoculated with Paracoccidioides brasiliensis (strain 18) and sacrificed 2, 4, 6, 8 and 10 weeks after inoculation. At each time interval, lungs and adrenals were removed to estimate recoverability of the fungus, as well as to determine Th1 (IFN-gamma, TNF-alpha) and Th2 (IL-4 and IL-10) cytokine profiles. While viable fungi recoverability from the lungs of HIV-A mice was higher after 4 and 8 weeks, there was less fungal recovery from the adrenals of LIV-A animals after the 2nd week, with total fungal elimination after the 8th week. With regard to Th2 cytokines, there was an inhibition in IL-4 production in the organs from infected animals, the extent of which varied according to the organ and the time period after initiation of infection. IL-10 production was found to be lower in both organs. Determination of Th1 cytokines revealed that IFN-gamma production increased in both organs, mainly in the adrenal of LIV-A after 8 and 10 weeks, when these animals showed a total fungal elimination. A significant difference was observed between HIV-A and LIV-A concerning TNF-alpha production in both organs and at all recovery times, in that LIV-A produced a higher level of this cytokine, mainly in the adrenal. These results may explain the high susceptibility of HIV-A to P. brasiliensis infection, is due, at least in part, to adrenal involvement. The higher production of Th1 cytokines by LIV-A in comparison to HIV-A mice may account for LIV-A resistance to P. brasiliensis infection. Our data reveal the importance of this experimental model in the study of the adrenal involvement in paracoccidioidomycosis, since this gland may be highly compromised in the patients, leading to the development of Addison's Disease.


Assuntos
Glândulas Suprarrenais/metabolismo , Citocinas/biossíntese , Pulmão/metabolismo , Paracoccidioides , Paracoccidioidomicose/imunologia , Células Th1/imunologia , Animais , Anticorpos Antifúngicos/biossíntese , Citocinas/análise , Masculino , Camundongos , Camundongos Endogâmicos , Células Th1/metabolismo , Células Th2/imunologia
9.
Nucl Med Commun ; 22(10): 1109-17, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11567184

RESUMO

The status of the homolateral axillary lymph nodes is still the most important prognostic factor in early stage breast cancer. The information obtained from the pathological examination of the lymph nodes guides is of critical importance in the decision process regarding the use of postoperative adjuvant therapy. However, lymph node axillary dissection can be followed by significant locoregional morbidity. The sentinel lymph node (SLN) technique was developed as a means of avoiding the full exploration of the axilla and consists in the identification of the first lymph node in the lymphatic drainage system of the breast tumour in the homolateral axilla. It has been demonstrated that the status of the SLN is highly predictive for the presence or absence of tumour involvement in the remaining lymph nodes in the axilla. In this study we evaluated the SLN technique using both 99mTc labelled dextran 500 and patent blue V dye in relation to the classical lymph node resection a series of 56 women with early breast cancer who attended the Breast Unit of the Academic Hospital of the Federal University of Rio Grande do Sul, Brazil. To our knowledge this is the first report in the literature of the utilization of 99mTc dextran 500 for the SLN technique. As there are no similar commercially available dedicated radiopharmaceuticals labelled for use in lymphoscintigraphy studies, we report on an effective method to label dextran 500 with 99mTc which proved to be simple, inexpensive and yielded similar results for SLN identification compared with those given in the literature. The median age of the patients was 57 years (range 32-82 years). Seventeen patients were age 50 years or less, and 39 patients were older than 50 years. The median tumour size was 2.0 cm (range 0.8-7.0 cm). The mapping of the SLN was possible in all cases during the transoperative period by using a hand-guided gamma probe and a blue dye. A median of 2.0 (range 1-5) SLN were excised per patient. The median of axillary lymph nodes excised per patient was 21 (range 10-36). The calculated sensitivity and specificity of the method were 95.6% and 100%, respectively. The negative predictive value and overall accuracy were 97% and 98.2%, respectively. In conclusion, the SLN technique was feasible and produced similar positive results as previously reported in the literature.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Linfonodos/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Corantes , Dextranos , Feminino , Humanos , Pessoa de Meia-Idade , Compostos de Organotecnécio , Valor Preditivo dos Testes , Estudos Prospectivos , Cintilografia , Compostos Radiofarmacêuticos , Corantes de Rosanilina
10.
J Mater Sci Mater Med ; 8(12): 815-8, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15348797

RESUMO

Granules of a modified hydroxyapatite, Osteopatite, were implanted in the right posterior tibiae of adult rabbits. We studied the extent of bone regeneration in bone holes. In the right tibiae, that were filled with granules of this biomaterial covered with a polytetrafluoro-ethylene (PTFE) membrane using, as a control, uncovered granules. In the left tibia, an empty hole was covered with PTFE membrane and a second hole was left empty to be used as a control. A histomorphometric study was carried out using light microscopy, four and eight weeks after the surgery. The covered granules presented a higher percentage of bone contact than the uncovered ones, and it was also possible to observe a better bone tissue organization, mainly produced by the immobilization action of the PTFE membrane. Empty bone defects covered with PTFE membranes, two months after implantation, presented large areas of Haversian bone and direct bone contact to the PTFE membrane.

11.
Stoma (Lisb) ; 2(18): 7-10, 13-5, 1991.
Artigo em Português | MEDLINE | ID: mdl-2038727

RESUMO

The authors describe in review the alveolar absorption according to bone physiology, and the absorption prevention using hydroxylapatite. Finally it is pointed the good preliminary results in a 30 patients study during 8 months using hydroxylapatite (OSTEOPATITE) and plaster particles in alveolar absorption prevention.


Assuntos
Perda do Osso Alveolar/prevenção & controle , Aumento do Rebordo Alveolar/métodos , Hidroxiapatitas , Sulfato de Cálcio , Implantes Dentários , Humanos , Osteogênese , Extração Dentária
13.
Rev Port Estomatol Cir Maxilofac ; 30(4): 185-93, 1989.
Artigo em Português | MEDLINE | ID: mdl-2640352

RESUMO

Two high copper-containing amalgam alloys, one of them gas atomized and the other water atomized were used to study the reaction mechanism with mercury. Normal and subtrituration time were used. The observations of structures and evaluation of compressive strengths allowed the understanding of two different mechanisms of reaction.


Assuntos
Amálgama Dentário , Cobre , Teste de Materiais , Mercúrio
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