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1.
Chemosphere ; 175: 534-542, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28254718

RESUMO

Water reuse for aquifer recharge could be an important route for the introduction of emerging organic contaminants (EOCs) into the environment. The installation of a Horizontal Permeable Reactive Barrier (H-PRB) could constitute a tertiary treatment process to remove EOCs from treated domestic wastewater prior to recharge activities. The sorption-desorption behaviour of six neutral EOCs present in treated domestic wastewater (acetaminophen, caffeine, carbamazepine, cotinine, 4-acetamidoantipyrine (4-AAA) and 4-formylaminoantipyrine (4-FAA)) has been evaluated. Clinoptilolite and palygorskite have been studied as sorbents to be installed in the H-PRB. Batch tests were carried out using an EOC initial concentration ranging from 5 to 100 µg L-1. Apart from acetaminophen and caffeine, both materials showed a limited sorption capacity of neutral EOCs (Kd = 0.63-5.42 L kg-1). In general, the experimental results show that EOCs exhibit a higher sorption affinity for clinoptilolite than for palygorskite. With the exception of carbamazepine, the sorption of the compounds occurs mainly by interactions with mineral surfaces as indicated by the comparison of the partition coefficients into organic matter and into mineral surfaces. According to the molecular geometry of the compounds and the sorption sequences observed, it appears that the dimensions of the organic molecules play a key role in the sorption process. All the studied EOCs exhibit irreversible sorption and sorption-desorption hysteresis.


Assuntos
Compostos de Magnésio/química , Preparações Farmacêuticas/análise , Compostos de Silício/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Zeolitas/química , Adsorção , Aminopirina/análogos & derivados , Aminopirina/análise , Água Subterrânea/química , Modelos Teóricos , Espanha , Propriedades de Superfície
2.
J Chromatogr A ; 1460: 181-9, 2016 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-27452991

RESUMO

The combination of thin layer chromatography (TLC) and mass spectrometry (MS) has been studied for decades, but for most cases MS detection is done after TLC separation is finished. Here, an online simultaneous TLC-MS analysis system, liquid thin layer chromatography-mass spectrometry (LTLC-MS), is developed which successfully synchronize TLC separation process and MS detection process like GC-MS and HPLC-MS do. And there's no need to use specially designed TLC, just regular TLC plates are enough. LTLC-MS method is composed of a newly developed ambient ionization method, glow discharge-matrix assisted infrared desorption ionization (GD-MAIRDI), and forced-flow TLC (FFTLC) technique, which guarantees the MS detection process does not disturb the TLC separation process throughout the whole analysis. The whole LTLC-MS analysis only need two steps and less than 15min. Mixtures as well as the two main components of a pain relief pills have been successfully analyzed by LTLC-MS. This proof of concept study opens up new possibilities of combining TLC with MS, and will further broaden the application abilities of TLC.


Assuntos
Analgésicos/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Fina/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Aminopirina/análise , Analgésicos/química , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia em Camada Fina/instrumentação , Fenacetina/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/instrumentação , Comprimidos/química
3.
J Sep Sci ; 38(23): 4048-54, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26434939

RESUMO

The concentrations of residual aminopyrine and antipyrine in porcine muscle, milk, and egg samples were analyzed using liquid chromatography with tandem mass spectrometry after undergoing a series of sample pretreatment steps. Owing to an ion suppression effect, matrix-matched calibrations were used for analyte quantitation with determination coefficients (R(2) ) ≥ 0.9931. The recovery rates for aminopyrine and antipyrine in various matrices at two spiking levels (5 and 10 ng/g) fell in the range of 60.96-68.87 and 61.87-66.99%, respectively. Meanwhile, the intra- and inter-day precisions (expressed as relative standard deviation) were 1.02-12.95 and 1.71-5.50%, respectively. The method's detection limit (1 ng/g) was very low, thus enabling the detection of low residue levels. The applicability of the developed method was demonstrated with actual market samples and none of the tested analytes was detected in any of the samples.


Assuntos
Aminopirina/análise , Antipirina/análise , Cromatografia Líquida , Ovos/análise , Análise de Alimentos/métodos , Leite/química , Músculos/química , Espectrometria de Massas em Tandem , Aminopirina/metabolismo , Animais , Antipirina/metabolismo , Limite de Detecção , Estrutura Molecular , Suínos
4.
Forensic Sci Int ; 247: 48-53, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25544694

RESUMO

Here, gas chromatography with nitrogen phosphorous detector (GC-NPD) method was developed and validated for the quantification of cocaine and adulterants (caffeine, 4-dimethylaminoantipyrine, levamisole, lidocaine and phenacetin) in illicit samples. The method was based on direct dilution of samples in methanol, sonication for 5 min and centrifugation. After appropriate dilution, an aliquot was injected into GC-MS in order to identify the active compounds and into GC-NPD for the analytes quantification. Bupivacaine was used as an internal standard. The method showed to be precise, accurate and linear over a range of 0.5-100% (weight/weight percentages) for all analytes, except phenacetin which showed a linear range between 2% and 100%. The method was successfully applied to 54 samples seized by the Brazilian Federal Police in the International Airport of Sao Paulo and mailing services during the year 2011. All the samples were associated with international trafficking and were apprehended while leaving the country. The purity of cocaine ranged from 16.5% to 91.4%. Cocaine was the only detected active compound in 29.6% of total samples. Among the identified cutting agents, levamisole was the most abundant (55.6% of the total samples) and relative concentrations (weight/weight percentages) ranged from 0.7% to 23%. Lidocaine, caffeine, phenacetin and 4-dimethylaminoantipyrine were also identified in these samples in minor concentrations. In contrast with what we initially hypothesized, drugs intended to international trafficking did not present high cocaine purity and most of the samples were laced with adulterants before leaving Brazil.


Assuntos
Cocaína/química , Contaminação de Medicamentos , Entorpecentes/química , Aminopirina/análise , Brasil , Cafeína/análise , Crime , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Levamisol/análise , Lidocaína/análise , Fenacetina/análise
5.
J Clin Gastroenterol ; 48(1): 59-65, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24335903

RESUMO

GOALS: We investigated the utility of liver function breath tests [C-Aminopyrine Breath Test (C-ABT), C-Galactose Breath Test (C-GBT)], for the diagnosis of nonalcoholic steatohepatitis (NASH) among nonalcoholic fatty liver disease (NAFLD) patients. BACKGROUND: Liver biopsy is currently the gold standard for the differentiation between simple fatty liver (NAFL) and NASH in NAFLD patients. MATERIALS AND METHODS: Thirty-six patients with histologically proven NAFLD (NAFL:16, NASH:20) underwent C-ABT and C-GBT. The results were expressed as the percentage of administered C dose recovered per hour (%dose/h) and as cumulative percentage of administered C dose recovered over time (%cumulative dose). Histologic lesions were scored according to Brunt and Kleiner's classifications. RESULTS: C-ABT results correlated inversely with activity grade (r=-0.650, P=0.001), NAFLD activity score (r=-0.473, P=0.026), and fibrosis stage (r=-0.719, P=0.001). Compared with NAFL, NASH patients had significantly lower %dose/h and %cumulative dose at 60, 90, and 120 minutes (always P<0.04) by C-ABT. C-ABT %dose/h and %cumulative dose at 120 minutes could predict the presence of NASH (area under the receiver operating characteristic curve: 0.762 and 0.741, respectively). In contrast, there was no significant association between C-GBT results and any patient characteristic. CONCLUSIONS: In the NAFLD patients, decreased and delayed liver microsomal function, as assessed by C-ABT, is associated with more severe necroinflammation and fibrosis, whereas C-ABT results at 120 minutes may be helpful for the diagnosis of NASH.


Assuntos
Testes Respiratórios/métodos , Fígado Gorduroso/diagnóstico , Testes de Função Hepática/métodos , Adulto , Idoso , Aminopirina/análise , Isótopos de Carbono , Estudos Transversais , Fígado Gorduroso/fisiopatologia , Feminino , Galactose/análise , Humanos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , Curva ROC , Índice de Gravidade de Doença , Fatores de Tempo
6.
Yao Xue Xue Bao ; 48(1): 94-7, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23600148

RESUMO

This paper reports the establishment of a method for rapid identification 15 effective components of anti common cold medicine (paracetamol, aminophenazone, pseudoephedrine hydrochloride, methylephedrine hydrochloride, caffeine, amantadine hydrochloride, phenazone, guaifenesin, chlorphenamine maleate, dextromethorphen hydrobromide, diphenhydramine hydrochloride, promethazine hydrochloride, propyphenazone, benorilate and diclofenac sodium) with MRM by LC-MS/MS. The samples were extracted by methanol and were separated from a Altantis T3 column within 15 min with a gradient of acetonitrile-ammonium acetate (containing 0.25% glacial acetic acid), a tandem quadrupole mass spectrometer equipped with electrospray ionization source (ESI) was used in positive ion mode, and multiple reaction monitoring (MRM) was performed for qualitative analysis of these compounds. The minimum detectable quantity were 0.33-2.5 microg x kg(-1) of the 15 compounds. The method is simple, accurate and with good reproducibility for rapid identification many components in the same chromatographic condition, and provides a reference for qualitative analysis illegally added chemicals in anti common cold medicine.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Antipiréticos/análise , Acetaminofen/análise , Acetanilidas/análise , Amantadina/análise , Aminopirina/análise , Antipirina/análogos & derivados , Antipirina/análise , Cafeína/análise , Clorfeniramina/análise , Cromatografia Líquida , Diclofenaco/análise , Difenidramina/análise , Contaminação de Medicamentos , Estabilidade de Medicamentos , Efedrina/análogos & derivados , Efedrina/análise , Guaifenesina/análise , Prometazina/análise , Pseudoefedrina/análise , Reprodutibilidade dos Testes , Salicilatos/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
7.
Isotopes Environ Health Stud ; 45(3): 185-91, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19507081

RESUMO

The aim of this study was to investigate the hepatic microsomal and cytosolic functions by using the 13CO2 breath test in healthy subjects either before or after consumption of red wine. Twelve adults received [13C2]aminopyrine and L-[1-13C]phenylalanine together with a standardised dinner. Expired air samples were taken over 6 h. After a wash-out period, the subjects consumed 0.4 ml ethanol per kg per day together with dinner over a 7.5-day period on average. Thereafter, 13C-tracer administration was repeated under identical conditions. The 13CO2 enrichments were measured by isotope ratio mass spectrometry. The mean cumulative percentage 13C-dose recovery after administration of [13C2]aminopyrine and L-[1-13C]phenylalanine either without or with red wine consumption amounted to 17.0+/-4.4 vs. 14.7+/-3.1% (p=0.170) and 14.0+/-2.8 vs. 11.5+/-3.9% (p=0.084), respectively. Moderate alcohol consumption does not induce significant short-term changes of the microsomal and the cytosolic function of the human liver in healthy subjects.


Assuntos
Aminopirina/análise , Testes Respiratórios , Isótopos de Carbono , Etanol/farmacologia , Fígado/efeitos dos fármacos , Fenilalanina/análise , Adulto , Aminopirina/metabolismo , Dióxido de Carbono/análise , Estudos Cross-Over , Relação Dose-Resposta a Droga , Feminino , Humanos , Fígado/metabolismo , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Fenilalanina/metabolismo , Vinho , Adulto Jovem
8.
J Intern Med ; 260(2): 142-50, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16882278

RESUMO

OBJECTIVES: Noninvasive evaluation of fibrosis is an on-going effort in the management of chronic hepatitis C. This study was planned to noninvasively evaluate fibrosis staging. DESIGN: We evaluated the biochemical, functional [aminopyrine breath test (ABT)] and ultrasonographic variables of 75 chronic hepatitis C patients. RESULTS: Clinical [body mass index (BMI)], biochemical [aspartate aminotransferase (AST), alanine aminotransferase (ALT) and platelets (PLT)] and ratio indexes, together with the ABT, showed a higher relationship with fibrosis: initial (score2) fibrosis: BMI (24+/-2 vs. 26+/-2, P=0.0007), AST (56+/-36 vs. 88+/-65, P=0.0159), ALT (92+/-54 vs. 139+/-108, P=0.0290), PLT (220+/-64 vs. 173+/-61, P=0.0007), PLT/spleen diameter ratio (PLT/SPD) (2133+/-786 vs. 1540+/-681, P=0.0003), AST/platelet count ratio index (APRI) (0.80+/-0.87 vs. 1.51+/-1.47, P=0.0010), ABT%d/h30 min (10.8+/-4.5 vs. 7.6+/-3.8, P=0.0007), ABT%d/cum120 min (8.9+/-3.3 vs. 6.5+/-3.1, P=0.0007). Considering the differences between fibrosis score 2 and 3 patients, BMI, ABT and PLT/SPD ratio proved to be statistically significant. Multivariate stepwise analysis (with and without BMI) identified two models for distinguishing between initial and evident fibrosis: Model 1: -0.569+(BMIx0.107)+(APRIx0.169)-(PLT/SPDx0.304), and Model 2: 2.376+( APRIx0.152)-(ABTd/h30x0.043)-(PLT/SPDx0.249). These models showed concordance in identifying or ruling out evident fibrosis in 76% and 78.7% of the patients respectively. The PLT/SPD ratio also showed 78.7% concordance with the histological score. CONCLUSION: These results suggest that noninvasive evaluation of fibrosis in chronic hepatitis C may be considered an effective tool thanks to the use of an inexpensive, reproducible ratio index.


Assuntos
Hepatite C Crônica/patologia , Fígado/patologia , Adulto , Aminopirina/análise , Biomarcadores/análise , Testes Respiratórios , Feminino , Fibrose , Hepatite C Crônica/sangue , Hepatite C Crônica/diagnóstico por imagem , Humanos , Fígado/diagnóstico por imagem , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Curva ROC , Baço/diagnóstico por imagem , Estatísticas não Paramétricas , Ultrassonografia
9.
Liver Int ; 26(4): 439-44, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16629647

RESUMO

BACKGROUND/AIM: To evaluate the relationship between hyaluronic acid/aminopyrine breath test (HA/ABT) ratio and fibrosis score in chronic hepatitis, and between HA/ABT and clinical staging (child-turcotte-pugh'score, CTP; and model for end stage liver disease, MELD) in cirrhosis, as well as to evaluate the aspartate aminotransferase (AST)/ABT in relation to the HA/ABT. METHODS: We studied 48 patients with histologically proven chronic hepatitis C (CHC) and 35 patients with compensated cirrhosis (CIR). RESULTS: HA/ABT and AST/ABT showed a more significant correlation with the fibrosis score than HA or ABT or AST alone in the 48 CHC patients: r=0.568 (P<0.0001), r=0.610 (P<0.0001), r=0.450 (P=0.0021), r=-0.449 (P=0.0021), and r=0.472(P=0.0012), respectively. Progressive liver damage (fibrosis 1-2 vs fibrosis 3-6 vs cirrhosis) was significantly (P<0.05) reflected by both HA/ABT (mean+/-SEM: 4.0+/-0.9 vs 18.1+/-4.2 vs 149.9+/-33.1) and AST/ABT (6.3+/-1.8 vs 12.7+/-1.6 vs 42.1+/-14.6). A strong relationship was found between HA/ABT and AST/ABT (r=0.755 P<0.0001). In cirrhotic patients, the most significant relationship was observed between HA/ABT and CTP r=0.483 and P=0.0049, and MELD r=0.523 and P=0.0023. CONCLUSION: Considering that HA levels in chronic hepatitis depend on the progressive impairment of sinusoidal endothelial cells (SEC), related to progressive fibrosis, HA/ABT ratio would seem to be the most specific reflection of progressive impairment of the SEC. AST/ABT could be used as a possible surrogate of HA in identifying SEC impairment in chronic hepatitis.


Assuntos
Aspartato Aminotransferases/sangue , Hepatite C Crônica/sangue , Ácido Hialurônico/sangue , Cirrose Hepática/sangue , Fígado/fisiopatologia , Adulto , Aminopirina/análise , Biomarcadores/sangue , Biópsia , Testes Respiratórios , Progressão da Doença , Endotélio/patologia , Feminino , Hepatite C Crônica/patologia , Hepatite C Crônica/fisiopatologia , Humanos , Fígado/patologia , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade
10.
Anal Biochem ; 351(2): 174-80, 2006 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-16359633

RESUMO

A method for simultaneous, nondestructive analysis of aminopyrine and phenacetin in compound aminopyrine phenacetin tablets with different concentrations has been developed by principal component artificial neural networks (PC-ANNs) on near-infrared (NIR) spectroscopy. In PC-ANN models, the spectral data were initially analyzed by principal component analysis. Then the scores of the principal components were chosen as input nodes for the input layer instead of the spectral data. The artificial neural network models using the spectral data as input nodes were also established and compared with the PC-ANN models. Four different preprocessing methods (first-derivative, second-derivative, standard normal variate (SNV), and multiplicative scatter correction) were applied to three sets of NIR spectra of compound aminopyrine phenacetin tablets. The PC-ANNs approach with SNV preprocessing spectra was found to provide the best results. The degree of approximation was performed as the selective criterion of the optimum network parameters.


Assuntos
Aminopirina/análise , Redes Neurais de Computação , Fenacetina/análise , Combinação de Medicamentos , Análise de Componente Principal/métodos , Espectrofotometria Infravermelho , Comprimidos/análise
11.
Clin Gastroenterol Hepatol ; 3(3): 279-85, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15765448

RESUMO

BACKGROUND AND AIMS: Liver biopsy examination is the gold standard to diagnose the presence of cirrhosis. The aim of this study was to evaluate the accuracy of both 13 C-aminopyrine breath test ( 13 C-ABT) and 13 C-galactose breath test ( 13 C-GBT) in the noninvasive assessment of the presence of cirrhosis in patients with chronic liver disease. METHODS: We evaluated 61 patients with chronic liver disease of diverse etiologies (21 compensated cirrhosis). All patients underwent 13 C-GBT and 13 C-ABT, and the results were expressed as a percentage of the administered dose of 13 C recovered per hour (%dose/h) and as the cumulative percentage of administered dose of 13 C recovered over time (%dose cumulative). Results were analyzed according to absence vs presence of cirrhosis. RESULTS: On average, 13 C-GBT %dose/h and %dose cumulative were decreased significantly in patients with compensated cirrhosis, and the same finding was observed for 13 C-ABT results from 30 to 120 minutes. 13 C-GBT %dose/h at 120 minutes had 71.4% sensitivity, 85.0% specificity, and 83.7% accuracy, whereas 13 C-ABT %dose cumulative at 30 minutes had 85.7% sensitivity, 67.5% specificity, and 77.1% accuracy for distinguishing between the 2 subgroups of patients. Combined assessment of 13 C-GBT and 13 C-ABT increased the diagnostic accuracy (80% positive predictive value) of either test alone and reached 92.5% specificity and 100% sensitivity for the diagnosis of cirrhosis. CONCLUSIONS: In patients with chronic liver disease, both 13 C-GBT and 13 C-ABT are useful for the diagnosis of cirrhosis. Combination of the tests increases the diagnostic yield of each test alone.


Assuntos
Aminopirina/análise , Testes Respiratórios , Galactose/análise , Cirrose Hepática/diagnóstico , Testes de Função Hepática/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
12.
Liver Int ; 24(5): 502-9, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15482349

RESUMO

BACKGROUND/AIMS: Halofuginone (HF) is an antifibrotic agent in rat models of liver fibrosis caused by repetitive intoxications. A beneficial effect of HF on a biliary type of liver fibrosis has not been proven yet. METHODS: Bile duct-obstructed rats were given HF from the moment of obstruction onwards and compared with no treatment. After 3 weeks, respectively, 6 weeks, aminopyrine breath test (ABT) and haemodynamic measurements including of portal pressure were carried out. Liver pieces were taken for Sirius red quantitative scoring, as well as for semiquantitative determinations of collagen type I and III RNA levels. RESULTS: ABT was significantly worse in HF-treated rats as compared with no treatment (P=0.02). Haemodynamic data and collagen type I and III determinations were not significantly different between groups. Biliary fibrosis scores were significantly higher in HF-treated rats as compared with no treatment (P=0.03). More Sirius red staining was associated with more proliferation of bile ductules. CONCLUSIONS: HF may worsen biliary fibrosis. This contrasts sharply with antifibrotic effects in other models of liver fibrosis. Distinctive cellular mechanisms in biliary fibrosis may explain this discrepancy. One should be cautious for chronic application of HF in man with cholestasis.


Assuntos
Cirrose Hepática Biliar/tratamento farmacológico , Cirrose Hepática Experimental/tratamento farmacológico , Fígado/patologia , Quinazolinas/efeitos adversos , Aminopirina/análise , Aminopirina/metabolismo , Animais , Ductos Biliares/cirurgia , Testes Respiratórios , Colestase Extra-Hepática/etiologia , Colestase Extra-Hepática/patologia , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Colágeno Tipo III/genética , Colágeno Tipo III/metabolismo , Modelos Animais de Doenças , Ligadura , Fígado/metabolismo , Cirrose Hepática Biliar/mortalidade , Cirrose Hepática Biliar/patologia , Cirrose Hepática Experimental/mortalidade , Cirrose Hepática Experimental/patologia , Masculino , Piperidinas , Pressão na Veia Porta , Quinazolinonas , RNA Mensageiro , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Gut ; 53(8): 1075-81, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15247171

RESUMO

BACKGROUND AND AIMS: Acid secretion plays an important role in the ecology of Helicobacter species and acid secretory status heralds patterns of gastritis. The presence of inflammatory cells and their products, in close proximity to parietal cells, questions the extent of the effect of cytokines on acid secretion. METHODS: We adopted and extensively characterised the mouse gastric gland preparation and its secretory capacity, which was measured using (14)C-aminopyrine accumulation. Subsequently, we tested the secretory properties of a wide range of species specific cytokines, including those associated with Th1 and Th2 immune responses. RESULTS: (14)C-aminopyrine accumulation in mouse gastric glands was shown to be a very sensitive "in vitro" method of testing classical secretagogues and antisecretory compounds, and provided pharmacological data on acid secretion in the mouse. Only two mouse cytokines, interleukin 2 and interferon gamma, had a direct effect on acid secretion causing dose dependent inhibition. CONCLUSIONS: Both cytokines belong to the Th1 type immune response and consequently their inhibitory effect may play a role in the hyposecretion seen with H pylori infection and colonisation throughout the corpus of the stomach that potentially can lead to gastric atrophy and subsequently, in some cases, cancer.


Assuntos
Citocinas/imunologia , Ácido Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Células Th1/imunologia , Aminopirina/análise , Animais , Carbacol/farmacologia , Agonistas Colinérgicos/farmacologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Feminino , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/imunologia , Gastrinas/farmacologia , Helicobacter pylori/fisiologia , Histamina/farmacologia , Interferon gama/imunologia , Interleucina-2/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Pentagastrina/farmacologia , Estômago/efeitos dos fármacos , Estômago/imunologia
15.
J Hepatol ; 37(5): 572-7, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12399221

RESUMO

BACKGROUND: Thrombocytopenia can be found in patients with chronic hepatitis related to hepatitis C virus (HCV). Both hypersplenism and decreased liver production of thrombopoietin (TPO) have been hypothesized as mechanisms responsible for thrombocytopenia. AIMS: To assess the presence of relationships among platelet count, spleen size, TPO serum levels, liver histology, and liver function in a group of patients with HCV-related chronic hepatitis. METHODS: Platelet count, TPO serum levels, and spleen size were assessed in 25 untreated HCV positive chronic hepatitis patients undergoing liver biopsy. These parameters were correlated to liver histology and liver function as evaluated by means of [(13)C]aminopyrine breath test (ABT). RESULTS: Both platelet counts (146 +/- 48 vs. 202 +/- 56 x 10(9)/1, P < 0.03) and TPO serum levels (103 +/- 24 vs. 158 +/- 7 1 pg/ml, P < 0.02) were lower among patients with high fibrosis scores as compared to patients with low fibrosis scores. Patients with thrombocytopenia as well as patients with high fibrosis scores had lower ABT results as compared to patients with normal platelet counts and patients with no or mild fibrosis, respectively. TPO serum levels were correlated to platelet count (r(s) = 0.493, P = 0.016), and negatively correlated to fibrosis stage (r(s) = -0.545, P = 0.008). Lastly, low TPO serum levels were associated to a decrease in liver function. CONCLUSIONS: Our study showed that in patients with chronic hepatitis related to HCV infection serum TPO levels are correlated to liver functional impairment and to the degree of liver fibrosis.


Assuntos
Hepatite C Crônica/sangue , Fígado/metabolismo , Trombopoetina/sangue , Adulto , Aminopirina/análise , Testes Respiratórios , Isótopos de Carbono , Feminino , Hepatite C Crônica/patologia , Humanos , Fígado/patologia , Cirrose Hepática/sangue , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Necrose , Contagem de Plaquetas , Baço/patologia , Trombocitopenia/sangue
16.
Isotopes Environ Health Stud ; 38(2): 71-7, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12219983

RESUMO

The [13C]aminopyrine breath test ([13C]ABT) measures the global activity of cytochrome P450 in vivo and is a sensitive indicator of liver metabolic dysfunction. The present study aims to determine whether gender and cigarette smoking influence the results of [13C]ABT as well as to confirm the effect of oral contraceptive steroids (OCS) intake on this metabolic test. Hundred and ten healthy subjects, including men and women, smoker and non-smoker, women taking OCS or not, were phenotyped for CYP1A2 using the [13C]caffeine breath test and underwent a [13C]ABT. Both tests showed large inter-individual variations in accordance with that of CYP450 liver content. [13C]ABT was sensitive enough to point out a significant induction or inhibition related to cigarette smoking habits or OCS. The combined effect of smoking and OCS resulted in an overall unchanged metabolic activity. Consequently, the impact of the studied conditions on the [13C]ABT parameters must be considered by clinicians or clinical investigators.


Assuntos
Aminopirina/análise , Cafeína/análise , Isótopos de Carbono/análise , Anticoncepcionais Orais/administração & dosagem , Fatores Sexuais , Fumar , Feminino , Humanos , Masculino , Valores de Referência , Nicotiana
17.
J Inorg Biochem ; 87(4): 185-90, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11744055

RESUMO

Semisynthetic flavocytochromes RfP450 1A2, RfP450 2B4 and RfP450scc--molecular conjugates of protein with riboflavin--could be reduced on rhodium-graphite screen-printed thick film electrodes as was confirmed by cyclic voltammograms of immobilized enzymes. Amperometric enzyme electrodes for direct measurement of organic pollutants were developed. The efficiency of controlled potential electrolysis for the reduction of flavocytochromes P450 was comparable with traditional reduction by pyridine nucleotides. The rate constants for substrates conversion obtained by electrochemical methods were close to those obtained using NAD(P)H as an electron source.


Assuntos
Proteínas de Bactérias , Técnicas Biossensoriais/instrumentação , Sistema Enzimático do Citocromo P-450/química , Aminopirina/análise , Colesterol/análise , Eletrodos , Enzimas Imobilizadas , Isoenzimas/química , Oxigenases de Função Mista/química , NADPH-Ferri-Hemoproteína Redutase , Oxirredução
18.
Gastroenterol Clin Biol ; 25(4): 375-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11449126

RESUMO

BACKGROUND AND AIMS: Isotope ratio mass spectrometry is the standard analytical method for (13)CO(2) breath tests. The goal of this study was to compare the results of (13)CO(2) breath tests obtained by non dispersive infrared spectrometry, a new, simpler and cheaper method, with those obtained by the gold standard method. METHODS: Three hundred and eight patients were included: 150 underwent a urea breath test for Helicobacter pylori diagnosis, 140 an aminopyrine breath test to measure liver function, and 18 an octanoic acid breath test for gastric emptying evaluation. A total of 750 breath samples were obtained in duplicate for isotope ratio mass and infrared spectrometry analyses. Breath test results were compared using Bland-Altman plots. RESULTS: The agreement between the two methods was excellent for urea breath tests (kappa coefficient=0.96), with only 3 discordant results. Although (13)C isotopic enrichment in breath was significantly lower with infrared spectrometry (P<0.0001), the agreement for the results of aminopyrine and octanoic acid breath tests was excellent. The clinical significance of these tests was similar for both methods. CONCLUSIONS: Infrared spectrometry results are comparable to isotope ratio mass spectrometry. Because this analytical method is simpler and less expensive, it could be used for clinical applications of (13)CO(2) breath tests.


Assuntos
Testes Respiratórios , Isótopos de Carbono , Espectrometria de Massas , Espectrofotometria Infravermelho , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aminopirina/análise , Caprilatos/análise , Feminino , Esvaziamento Gástrico , Infecções por Helicobacter/diagnóstico , Helicobacter pylori , Humanos , Modelos Lineares , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Ureia/análise
19.
Analyst ; 126(5): 664-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11394310

RESUMO

A molecularly imprinted polymer for aminopyrine was synthesized using methacrylic acid as functional monomer. The polymer was employed as the recognition element of a piezoelectric bulk acoustic wave biomimetic sensor for aminopyrine. Influencing factors were investigated in detail and optimized. This sensor exhibited high selectivity and sensitivity to aminopyrine. The response range of the sensor was between 5.0 x 10(-8) and 1.0 x 10(-4) M with a detection limit of 2.5 x 10(-8) M in the aqueous system. Scatchard analysis with UV spectrophotometry showed that the same class of binding sites was formed in the molecularly imprinted polymer in the studied concentration range, and the dissociation constant and the apparent maximum number of these binding sites were estimated to be 2.29 mM and 165.0 mumol g-1 dry polymer, respectively. Impedance analysis was employed to verify the imprinting effect and lack of variation in the viscoelasticity of the polymer coating during detection.


Assuntos
Aminopirina/análise , Anti-Inflamatórios não Esteroides/análise , Aminopirina/sangue , Aminopirina/urina , Anti-Inflamatórios não Esteroides/sangue , Anti-Inflamatórios não Esteroides/urina , Eletroquímica/instrumentação , Eletroquímica/métodos , Humanos
20.
Dig Dis Sci ; 46(1): 133-9, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11270777

RESUMO

The aminopryine breath test (ABT) measures hepatic reserve in patients with acute and chronic liver disease and gives an assesment of the hepatic function in patients undergoing major liver surgery. Aminopyrine is metabolized by the mixed cytochrome P-450 system, which can be influenced by many foreign compounds and drugs. Whether these foreign compounds and drugs can influence the results of the ABT has seldomly been tested. We studied three groups: Healthy female volunteers, either normally menstruating or taking oral contraceptives, were asked to perform a [13C]ABT during the time of the menses and at midcylce. Healthy volunteers were asked to perform a ABT after consuming 30 g of alcohol. Healthy volunteers were asked to perform a ABT after consuming 250 ml of grapefruit juice. The 13C/12C ratio in expired air was measured by gas isotope ratio mass spectrometry.


Assuntos
Bebidas Alcoólicas , Aminopirina/análise , Bebidas , Testes Respiratórios/métodos , Citrus , Anticoncepcionais Orais Hormonais/farmacologia , Etinilestradiol/farmacologia , Testes de Função Hepática/métodos , Doença Aguda , Adolescente , Adulto , Aminopirina/metabolismo , Radioisótopos de Carbono , Doença Crônica , Inibidores das Enzimas do Citocromo P-450 , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Humanos , Hepatopatias/diagnóstico , Masculino , Menstruação/fisiologia
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