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1.
Int J Radiat Biol ; 96(12): 1597-1607, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32990492

RESUMO

PURPOSE: Depleted uranium (DU) has several civilian and military applications. The effects of this emerging environmental pollutant on human health raise some concerns. Previous experimental studies have shown that uranium (U) exposure can disturb the central nervous system. A small quantity of U reaches the brain via the blood, but the effects on the blood-brain barrier (BBB) remain unclear. MATERIALS AND METHODS: In the present work, two cell culture models were exposed to DU for different times to study its cytotoxicity, paracellular permeability and extracellular concentration of U. The well-known immortalized human cerebral microvascular endothelial cells, hCMEC/D3, were cultured on the filter in the first model. In the second model, human primary cells of pericytes were cultured under the filter to understand the influence of cell environment after U exposure. RESULTS: The results show that U is not cytotoxic to hCMEC/D3 cells or pericytes until 500 µM (1.6 Bq.L-1). In addition, acute or chronic low-dose exposure of U did not disturb permeability and was conserved in both cell culture models. However, U is able to reach the brain compartment. During the first hours of exposure, the passage of U to the abluminal compartment was significantly reduced in the presence of pericytes. Electronic microscopy studies evidenced the formation of needlelike structures, like urchin-shaped precipitates, from 1 h of exposure. Analytical microscopy confirmed the U composition of these precipitates. Interestingly, precipitated U was detected only in endothelial cells and not in pericytes. U was localized in multilamellar or multivesicular bodies along the endo-lysosomal pathway, suggesting the involvement of these traffic vesicles in U sequestration and/or elimination. CONCLUSIONS: We show for the first time the in vitro passage of U across a human cerebral microvascular endothelial cells, and the intracellular localization of U precipitates without any cytotoxicity or modification of paracellular permeability. The difference between the results obtained with monolayers and co-culture models with pericytes illustrates the need to use complex in vitro models in order to mimic the neurovascular unit. Further in vivo studies should be performed to better understand the passage of U across the blood-brain barrier potentially involved in behavioral consequences.


Assuntos
Encéfalo/irrigação sanguínea , Células Endoteliais/metabolismo , Microvasos/citologia , Urânio/metabolismo , Barreira Hematoencefálica/metabolismo , Linhagem Celular , Técnicas de Cocultura , Células Endoteliais/efeitos da radiação , Espaço Extracelular/metabolismo , Espaço Extracelular/efeitos da radiação , Humanos , Permeabilidade , Fatores de Tempo
2.
Clin Lab ; 63(10): 1749-1753, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29035440

RESUMO

BACKGROUND: The pH may impact the concentration of certain urinary parameters, making urine pre-treatment questionable. METHODS: 1) Determining the impact of pH in vitro on the urinary concentration of chemistry parameters assayed on Roche Modular analyzers. 2) Evaluating whether concentrations depended on pH in non-pretreated urines from patients. RESULTS: 1) The optimal urinary pH values for each measurement were: 6.3 ± 0.8 (amylase), < 5.5 (calcium and magnesium), < 6.5 (phosphorus), > 6.5 (uric acid). Urinary creatinine, sodium and urea concentrations were not pH-dependent. 2) In urines from patients, the pH was negatively associated with the concentration of some urinary parameters. However, concentrations of all the parameters were strongly and positively correlated with urinary creatinine, and relationships with pH were no longer evidenced after creatinine-normalization. CONCLUSIONS: The need for urine pH adjustment does not seem necessary when considering renal function. However, from an analytical and accreditation standpoint, the relationship between urine pH and several parameters justifies its measurement.


Assuntos
Urinálise , Urina/química , Humanos , Concentração de Íons de Hidrogênio , Urinálise/instrumentação
3.
Aliment Pharmacol Ther ; 40(9): 1081-93, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25186086

RESUMO

BACKGROUND: In cardiometabolic disorders, non-alcoholic fatty liver disease is frequent and presumably associated with increased mortality and cardiovascular risk. AIM: To evaluate the prognostic value of non-invasive biomarkers of liver fibrosis (FibroTest) and steatosis (SteatoTest) in patients with type-2 diabetes and/or dyslipidaemia. METHODS: A total of 2312 patients with type-2 diabetes and/or dyslipidaemia were included and prospectively followed up for 5-15 years. The cardiovascular Framingham-risk score was calculated; advanced fibrosis and severe steatosis, were defined by FibroTest >0.48 and SteatoTest >0.69, respectively, as previously established. RESULTS: During a median follow-up of 12 years, 172 patients (7.4%) died. The leading causes of mortality were cancer (31%) and cardiovascular-related death (20%). The presence of advanced fibrosis [HR (95% CI)] [2.98 (95% CI 1.78-4.99); P < 0.0001] or severe steatosis [1.86 (1.34-2.58); P = 0.0002] was associated with an increased risk of mortality. In a multivariate Cox model adjusted for confounders: the presence of advanced fibrosis was associated with overall mortality [1.95 (1.12-3.41); P = 0.02]; advanced fibrosis at baseline [n = 50/677; 1.92 (1.04-3.55); P = 0.04] and progression to advanced fibrosis during follow-up [n = 16/127; 4.8 (1.5-14.9); P = 0.007] were predictors of cardiovascular events in patients with type-2 diabetes. In patients with a Framingham-risk score ≥20%, the presence of advanced fibrosis was predictive of cardiovascular events [2.24 (1.16-4.33); P < 0.05]. CONCLUSIONS: Liver biomarkers, such as FibroTest and SteatoTest, have prognostic values in patients with metabolic disorders. FibroTest has prognostic value for predicting overall survival in patients with type-2 diabetes and/or dyslipidaemia. In type-2 diabetes, FibroTest predicted cardiovascular events and improved the Framingham-risk score.


Assuntos
Diabetes Mellitus Tipo 2/diagnóstico , Dislipidemias/diagnóstico , Cirrose Hepática/diagnóstico , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Adulto , Idoso , Biomarcadores/sangue , Estudos de Coortes , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/mortalidade , Dislipidemias/sangue , Dislipidemias/mortalidade , Feminino , Seguimentos , Humanos , Cirrose Hepática/sangue , Cirrose Hepática/mortalidade , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/mortalidade , Prognóstico , Estudos Prospectivos , Fatores de Risco
4.
J Viral Hepat ; 19(7): 497-500, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22676362

RESUMO

Therapeutic options in hepatitis C virus (HCV)-related vasculitis may target the viral trigger using antiviral therapy [pegylated interferon plus ribavirin (PEG-IFN/RBV)], and/or the downstream B-cell arm of autoimmunity with rituximab (RTX). To date, no study has compared the efficacy of RTX combined with PEG-IFN/RBV on biomarkers of liver insufficiency in patients with severe liver fibrosis. Twenty-eight untreated HCV-related vasculitis patients with severe liver fibrosis (Metavir F3-F4) were included: 14 patients received RTX plus PEG-IFN/RBV and 14 patients PEG-IFN/RBV. The main clinical and biological data were recorded and compared at baseline, month 3 (M3), M12 and M24 of follow-up. Baseline epidemiological, clinical, virological and immunological features were similar between the groups. The virological response did not differ between cases and controls. The alanine aminotransferase (ALT) level and HCV viral load did not increase in patients treated with RTX. Serum albumin levels increased in patients treated with RTX at M3 and M6 (108% and 111% of baseline value; P = 0.06 and P = 0.13), whereas it was stable in patients treated without RTX. FibroTest values decreased from 0.70 at baseline to 0.59 at M3 (P = 0.5) and returned to 0.69 at M24 in the RTX-PEG-IFN/RBV group, whereas they were stable in the PEG-IFN/RBV group. RTX is safe in patients with severe HCV liver fibrosis and vasculitis. No beneficial effects of RTX were evidenced on liver fibrosis progression, but we found interesting correlations with the serum albumin level, FibroTest values and B-cell count.


Assuntos
Anticorpos Monoclonais Murinos/administração & dosagem , Antivirais/administração & dosagem , Biomarcadores/sangue , Insuficiência Hepática/patologia , Interferons/administração & dosagem , Cirrose Hepática/patologia , Ribavirina/administração & dosagem , Idoso , Alanina Transaminase/sangue , Monitoramento de Medicamentos , Feminino , Hepacivirus/isolamento & purificação , Insuficiência Hepática/tratamento farmacológico , Humanos , Cirrose Hepática/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Rituximab , Resultado do Tratamento , Carga Viral
5.
Gastroenterol Clin Biol ; 34(6-7): 388-96, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20580175

RESUMO

BACKGROUND: ActiTest (AT) is a biomarker of liver necro-inflammatory histological activity validated in patients with chronic hepatitis C (HCV). AIM: The aim was to assess the accuracy of AT in comparison with alanine aminotransferase (ALT) the standard of care. METHODS: Methods used an integrated database of individual data and the new recommended Obuchowski measures. An updated "classical" meta-analysis of AT validation studies was also performed. The main end points were the area under the ROC curves (AUROCs) for the diagnosis of each histological activity grade defined using METAVIR scoring system. To avoid repeated tests and the spectrum effect of activity grades prevalence, the comparison of AT and ALT accuracies used the Obuchowski method. RESULTS: For the individual analysis, a total of 1250 patients were included and for the meta-analysis six studies (2017 patients) were included. The overall accuracy of AT for the diagnosis of any activity grade (Obuchowski measure=0.850) was significantly higher than the accuracy of ALT (Obuchowski measure=0.837; P=0.009). The updated standard meta-analysis confirmed the accuracy of AT (p<0.0001) both in independent AUROC=0.79 (95% CI, 0.73-0.85) and in non independent studies AUROC=0.74 (95% CI, 0.67-0.81). CONCLUSIONS: The accuracy of AT for grading the necro-inflammatory activity of patients with HCV was significantly higher than ALT serum activity alone, the standard biomarker.


Assuntos
Alanina Transaminase/sangue , Hepatite C Crônica/sangue , Hepatite C Crônica/patologia , Curva ROC , Adulto , Biomarcadores/sangue , Biópsia , Análise Química do Sangue , Feminino , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade
7.
Gastroenterol Clin Biol ; 32(6 Suppl 1): 8-21, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18973843

RESUMO

This review summarizes the methodological aspects of the interpretation of non-invasive biomarkers in liver fibrosis. A scoring system has been updated to better compare the quality of fibrosis biomarkers. Several methodological issues are related to the classical methodology using biopsy, as this is considered the gold standard. However, from evidence-based data, it appears that the methodology needs to change to prevent flawed conclusions among key opinion leaders as well as in obsolete guidelines. As waiting for the perfect biomarker for the diagnosis of advanced fibrosis to come along is probably a waste of time, in the meantime, methods can be improved. The main proposals for improving the methodology are, to take into account the spectrum bias, to assess accuracy between adjacent stages, to compare biomarkers in the same patient, to assess the cause of failure among discordant cases and to use specific statistical methods adapted for imperfect gold standards.


Assuntos
Cirrose Hepática/diagnóstico , Biomarcadores/análise , Biópsia , Humanos
8.
Aliment Pharmacol Ther ; 26(6): 847-58, 2007 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-17767469

RESUMO

BACKGROUND: FibroTest has been validated for the diagnosis of liver fibrosis in patients with chronic hepatitis C. AIM: To compare FibroTest with a new proteome-based model for the prediction of advanced liver fibrosis. METHODS: Sera from 191 consecutive patients with simultaneous liver biopsy and FibroTest on fresh sera were used for retrospective mass spectrometry analysis. A new fibrosis index was constructed combining proteomic peaks, selected on differential expression according to fibrosis stages in logistic regression analyses. The main end point was the diagnosis of advanced fibrosis on liver biopsy. RESULTS: Eight out of 1000 peaks were selected for the construction of the proteomic index. The area under the receiver operating curve (AUROC) of the proteomic index was 0.88 (95% CI: 0.82-0.92), significantly greater than the FibroTest AUROC of 0.81 (95% CI: 0.74-0.86; P = 0.04); the AUROC of the proteomic and FibroTest combination was 0.88 (95% CI: 0.83-0.92). Seven of the eight selected peaks were highly associated with the FibroTest score, with different patterns of association with the five components of FibroTest. CONCLUSIONS: A proteomic index combining eight peaks had an excellent accuracy value for the diagnosis of advanced fibrosis in patients with chronic hepatitis C. However, despite a statistical significance, the small improvement delivered by proteomics impairs clinical applications because of its cost and its variability compared with the well validated FibroTest.


Assuntos
Hepatite C Crônica/etiologia , Cirrose Hepática/diagnóstico , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Adulto , Biomarcadores/metabolismo , Biópsia , Feminino , Hepatite C Crônica/metabolismo , Humanos , Cirrose Hepática/metabolismo , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos
9.
Aliment Pharmacol Ther ; 26(3): 359-68, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17635370

RESUMO

BACKGROUND: The best technique to estimate portal hypertension (PHT) is to measure the hepatic venous pressure gradient (HVPG), which is an invasive method. AIM: To assess the relationship between the Fibrotest (Biopredictive, Paris, France) and the presence and degree of PHT in patients with liver disease, and to determine if the Fibrotest can diagnose severe PHT, defined by HVPG >or= 12 mmHg, in cirrhotic patients. METHODS: Patients who underwent a transjugular liver biopsy were prospectively included. HVPG was measured, and classification of histological lesions assessed. The same day, blood samples for Fibrotest were performed. RESULTS: A total of 130 patients were included (no or minimal fibrosis: 12%, moderate fibrosis 17%, cirrhosis 71%). There was a significant correlation between Fibrotest and HVPG (Pearson correlation coefficient = 0.58, P < 0.0001), also weaker in cirrhotic patients (Pearson correlation coefficient = 0.24, P = 0.02). In cirrhotic patients, Fibrotest was significantly higher when there was a severe PHT (0.87 +/- 0.15 vs. 0.73 +/- 0.14, respectively, P = 0.02). The areas under the receiver operating characteristic curves for the diagnosis of severe PHT was 0.79 +/- 0.07, not different from that of platelets and Child-Pugh score. CONCLUSION: In patients with liver disease or cirrhosis, Fibrotest is correlated with the presence and degree of PHT. Other studies are needed to confirm these results, especially in non-decompensated cirrhotic patients.


Assuntos
Hipertensão Portal/diagnóstico , Hepatopatias/diagnóstico , Pressão Venosa/fisiologia , Adulto , Biomarcadores/metabolismo , Feminino , Veias Hepáticas/metabolismo , Humanos , Hipertensão Portal/fisiopatologia , Hepatopatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos
10.
Aliment Pharmacol Ther ; 25(2): 207-18, 2007 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17229244

RESUMO

BACKGROUND: Mortality related to complications of cirrhosis is increasing in patients with insulin-resistance factors. Hyperlipidaemic patients have multiple risk factors of insulin resistance. It is impossible to perform liver biopsy in such a large number of hyperlipidaemic patients to identify patients with advanced liver fibrosis or with steatohepatitis (non-alcoholic steatohepatitis, NASH). AIMS: To use the non-invasive biomarkers, FibroTest (FT), SteatoTest and NashTest, and to assess the prevalence of advanced liver disease in a large population of hyperlipidaemic patients. METHODS: A consecutive cohort of hyperlipidaemic patients was followed prospectively in a lipid centre and the sera were analysed retrospectively. RESULTS: A total of 2834 subjects were included: 1909 hyperlipidaemic patients and 925 blood donors (BD). Advanced fibrosis was identified by FT in 53/1909 (2.8%) hyperlipidaemic patients vs. 0/925 BD (0%) (P < 0.0001); advanced steatosis in 569/1893 hyperlipidaemic patients (30.1%) vs. 8/164 (4.9%) BD (P < 0.0001) and NASH in 132/1893 (7%) vs. 0/164 (0%), respectively (P < 0.0001). There was a highly significant and linear association between the number of metabolic syndrome factors and liver disease prevalence - the highest being for type 2 diabetics: advanced steatosis 66%, NASH 24% and advanced fibrosis 6%. CONCLUSIONS The prevalence of fibrosis, steatosis and NASH in hyperlipidaemic patients appears to be high (3%, 30% and 7%, respectively). Biomarkers could be useful for screening of advanced fibrosis and NASH in patients with several metabolic syndrome factors, to prevent liver mortality.


Assuntos
Biomarcadores/sangue , Hepatopatias/diagnóstico , Testes de Função Hepática/normas , Diagnóstico Diferencial , Feminino , Humanos , Hiperlipidemias/complicações , Hepatopatias/etiologia , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Fatores de Risco
11.
Ann Biol Clin (Paris) ; 63(4): 385-95, 2005.
Artigo em Francês | MEDLINE | ID: mdl-16061437

RESUMO

BACKGROUND: Alpha2Macroglobulin (A2M) measure showed a revival since it was introduced into FibroTest-ActiTest-Fibro (FT-AT-Fibro) algorithm. More often than not, this assay is performed in immunonephelemetry. Progresses in the comprehension of fibrosis dynamics and better treatment efficacy follow-up will increase FT-AT-Fibro prescriptions. Despite efforts to standardize methods of enzymatic activity measure and proteins measure, we still observe important interlaboratory and intersystem variability. AIM: The primary aim of the study is to validate immunoturbidimetric measure of A2M on Modular P and Cobas Integra analysers (Roche Diagnostics) in utility channel using DakoCytomation reagents in order to extend the analytical system range allowed to measure A2M. The secondary aim of the study is to verify transferability of the six FT-AT composants (A2M, haptoglobin, apolipoprotein A1, total bilirubin, GGT and ALT) to Roche Diagnostics equipment by comparing with results measured on the reference system. RESULTS: A2M measures (n = 146) showed linearity, repetitiveness and were reproducible. Readjustments to adapt A2M measures were required. A corrector factor of 0.84 for Modular P and of 0.87 for Cobas Integra was introduced in order to readjust the immunoturbidimetric method to the immunonephelemetric method. The rationale of proposed corrector factors is based on the use of Dade Behring and DakoCytomation reagents (antisera and calibrant). Biologist vigilance is required to point out modifications or variations in reagents that could be done by the company. The six parameters results transferability from the reference system to Roche Diagnostics was demonstrated by statistic analysis. FT-AT showed excellent correlations to the reference system for Modular P and Cobas Integra analysers. In this study no difference more than 0.11 was recorded and only few subjects had differences between 0.05 and 0.10. Therefore this very low inter-analysers variability has no significant clinical impact. CONCLUSION: This study showed that the analytical system made of Modular P, Cobas Integra, Roche Diagnostics and DakoCytomation reagents can be used for FibroTest-ActiTest-Fibro parameters assessment. Their statistical and clinical variability were acceptable compared to the reference system.


Assuntos
alfa-Macroglobulinas/análise , Automação/métodos , Testes de Química Clínica , Humanos , Imunoensaio/métodos , Nefelometria e Turbidimetria/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Ann Biol Clin (Paris) ; 63(3): 305-13, 2005.
Artigo em Francês | MEDLINE | ID: mdl-15951262

RESUMO

The follow up of patients with chronic liver diseases and the data from multicentric clinical studies are affected by the variability of assay results for the same parameter between the different laboratories. Today, the main objective in clinical chemistry throughout the world is to harmonise the assay results between the laboratories after the confirmation of their traceability, in relation to defined reference systems. In this context, the purpose of our study was to verify the homogeneity of haptoglobin, apolipoprotein A1, total bilirubin, GGT activity, ALAT activity results, which are combined in Fibrotest and Actitest, between Dimension Analysers RXL, ARX and X-PAND (Dade Behring Society). Moreover, we verified the transferability of Fibrotest and Actitest results between the RXL, and either the BN2 (haptoglobin and apolipoprotein A1) or the Modular DP (total bilirubin, GGT and ALAT activity concentrations). The serum samples from 150 hospitalised patients were analysed on the different analysers. Specific protein assays were calibrated using solutions standardised against reference material on Dimension and BN2 analysers. Total bilirubin assays were performed by a diazoreaction on Dimension and Modular DP analysers. The GGT and ALAT activity measurements on the Dimension analysers were performed in accordance with the reference methods defined by the International Federation of Clinical Chemisty and Laboratory Medicine (IFCC). On the Modular, enzyme activity measurements were performed according to the Szasz method (L-gamma- glutamyl-4-nitroanilide as substrate) modified by Persijn and van der Slik (L-gamma- glutamyl-3-carboxy- 4-nitroanilide as substrat) for GGT and according to the IFCC specifications for ALAT. The methods of enzymatic activity measurement were calibrated on the Modular only. Liver fibrosis and necroinflammatory activity indices were determined using calculation algorithms, after having adjusted each component's result of Fibrotest and Actitest for gender and age. Our study has shown, for each parameter, harmonious results between the Dimension analysers and between RXL and BN2- Modular DP. Disregarding alpha-2 macroglobulin which cannot be assayed on RXL, the results of Fibrotest and Actitest were similar as performed on BN2- Modular DP and RXL.


Assuntos
Análise Química do Sangue/métodos , Análise Química do Sangue/normas , Testes Hematológicos/métodos , Testes Hematológicos/normas , Humanos , Padrões de Referência
13.
Ann Biol Clin (Paris) ; 62(6): 717-20, 2004.
Artigo em Francês | MEDLINE | ID: mdl-15563433

RESUMO

Effect of a pyridoxal phosphate (PP) supplementation of reagents used for ALT and AST measurement was studied in serum of 20 patients suffering from viral hepatitis. Measurements of enzyme activities were carried out at 37 degrees C, using an automate (AU 600, Olympus). Significant differences (p < 0.0001) were observed both for ALT and AST, meanwhile they were more marked for ALT than for AST. This difference was associated with a strong interindividual variability regarding PP activation effect on ALT. In conclusion, aminotransferase measurements should be carried out with a reagent supplemented with PP, when the enzyme activity is used to evaluate a cytolysis. The same recommendation applies when ALT results are integrated into various combinations developed for the evaluation of liver status.


Assuntos
Alanina Transaminase/sangue , Alanina Transaminase/efeitos dos fármacos , Aspartato Aminotransferases/sangue , Aspartato Aminotransferases/efeitos dos fármacos , Hepatite Viral Humana/sangue , Hepatite Viral Humana/enzimologia , Fosfato de Piridoxal/farmacologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Ann Biol Clin (Paris) ; 60(3): 281-6, 2002.
Artigo em Francês | MEDLINE | ID: mdl-12050043

RESUMO

Results of catalytic activities of enzymes are highly dependent on the measurement procedures and on local conditions. Thus, only poorly marked improvement of interlaboratory comparability of results have been observed in clinical enzymology. To solve this problem, SFBC and IFCC have proposed to use "validated enzyme calibrators". Standardised operating procedures adapted to 37 C have been developed by IFCC for the most commonly used enzymes in clinical chemistry, and will be soon published. Reference materials which have been certified with these SOPs can be used as calibrators for a set of measurement methods which exhibit the same analytical specificity. Calibrators must be commutable, a property that must be checked experimentally. It is possible to produce stable and commutable materials for the calibration of a set of methods. Interest of this approach has been demonstrated for several enzymes. Results of two studies presented here show that the comparison of results to the upper limit of reference ranges does not improve the interlaboratory comparability of results in contrast to the calibration of different methods by a common calibrator which allowed to reach an interlaboratory CV close to 4% for ALT and gammaGT.


Assuntos
Enzimas/sangue , Calibragem , Catálise , Química Clínica/métodos , Humanos , Sensibilidade e Especificidade
15.
J Viral Hepat ; 9(2): 128-33, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11876795

RESUMO

A liver fibrosis index was recently prospectively validated in a cross-sectional study where patients infected by hepatitis C virus (HCV) had only one biopsy and no longitudinal follow-up. The aim of this study was to retrospectively assess the diagnostic value of this index in patients included in a randomized trial of interferon (IFN) using repeated measurements, two biopsies and hyaluronic acid as a comparative reference. One-hundred and sixty-five patients who had had two interpretable liver biopsies and at least one stored serum sample before IFN treatment were selected. Seventy-eight patients received 3 MU of IFN-alpha thrice weekly for 24 weeks and 87 followed a reinforced regimen for 48 weeks. A fibrosis index combining five biochemical markers (alpha2-macroglobulin, haptoglobin, apolipoprotein A1, gamma-glutamyl transpeptidase (GGT) and total bilirubin adjusted for gender and age) as well as hyaluronic acid was assessed on 461 samples available at baseline, at the end of treatment and at the end of follow-up (72 weeks). There was a significant decrease of the fibrosis index score among the 17 sustained virologic responders, from 0.33 +/- 0.06 (mean +/- SE) at baseline to 0.18 +/- 0.06 at 72 weeks in comparison with 92 nonresponders (from 0.41 +/- 0.03 at baseline to 0.44 +/- 0.03 at 72 weeks; P < 0.001) and in comparison with 56 relapsers (from 0.36 +/- 0.03 at baseline to 0.32 +/- 0.03 at 72 weeks; P=0.05). No significant differences were observed for hyaluronic acid.Hence, this fibrosis index could be used as a surrogate marker of the antifibrotic effect of treatments in patients with chronic hepatitis C.


Assuntos
Antivirais/uso terapêutico , Apolipoproteína A-I/metabolismo , Bilirrubina/metabolismo , Haptoglobinas/metabolismo , Hepatite C/metabolismo , Interferon-alfa/uso terapêutico , Cirrose Hepática/metabolismo , alfa-Macroglobulinas/metabolismo , gama-Glutamiltransferase/metabolismo , Adulto , Idoso , Biomarcadores , Estudos Transversais , Feminino , Hepatite C/tratamento farmacológico , Hepatite C/patologia , Hepatite C/virologia , Humanos , Interferon alfa-2 , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Estudos Retrospectivos , Resultado do Tratamento
17.
Transplantation ; 72(3): 393-405, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11502966

RESUMO

BACKGROUND: The clinical development of liver-support devices based on perfusion of either pig hepatocytes cartridges or whole pig livers has been hampered by the ability to use sufficient liver cell mass to provide adequate metabolic support, limited perfusion times, and the potential for patient exposure to pig zoonotic diseases. METHODS: We designed an original system in which an isolated intact pig liver was perfused extracorporeally under physiological conditions in a closed loop circuit with allogeneic pig blood and constant monitoring of major physiological and functional parameters. The perfusion circuit further included an interface membrane to provide for separation of patient and liver perfusion circulation. RESULTS: Prolonged (6-21 hr) liver perfusion did not produce significant liver damage as reflected by modest rises in the levels of the serum transaminases, stability of main biochemical parameters (including potassium), and the maintenance of normal cellular morphology. Optimal liver function was documented as measured by lactate consumption, control of glycemia, and the results of clotting studies and functional assays. The perfused liver cleared 82% and 79% of peak bilirubin and ammonia concentrations with clearing kinetics identical throughout perfusion. Indocyanine green clearance was identical to that observed in the living donor before explant surgery. CONCLUSIONS: In conclusion, the extracorporeal pig liver perfusion apparatus described here allows optimal pig liver function for prolonged periods of time. The microporous membrane to provide separation of donor organ and recipient and the high level of functional activity suggest that this form of liver metabolic support may have important clinical applications.


Assuntos
Circulação Extracorpórea , Fígado/metabolismo , Amônia/sangue , Animais , Artérias , Bilirrubina/urina , Sangue/metabolismo , Fatores de Coagulação Sanguínea/biossíntese , Corpos Cetônicos/sangue , Fígado/patologia , Fígado/fisiologia , Testes de Função Hepática , Perfusão/instrumentação , Perfusão/métodos , Biossíntese de Proteínas , Suínos , Fatores de Tempo , Ureia/metabolismo
18.
Lancet ; 357(9262): 1069-75, 2001 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-11297957

RESUMO

BACKGROUND: Liver biopsy is thought mandatory for management of patients with hepatitis C virus (HCV) infection, especially for staging fibrosis. We aimed, in our prospective study, to assess the predictive value of a combination of basic serum biochemical markers for diagnosis of clinically significant fibrosis (including early stages). METHODS: We assessed liver-biopsy patients with detectable HCV by PCR, for eligibility, and took a blood sample on the day of the procedure. The analysis was done in a first-year period for 205 patients and then tested in a second period on 134 patients. We devised a fibrosis index that included the most informative markers (combined with age and sex) for the first-year group. 11 serum markers were assessed as well as fibrosis stage: F0=no fibrosis and F1=portal fibrosis; and for clinically significant fibrosis, F2=few septa, F3=many septa, and F4=cirrhosis. Statistical analysis was by logistic regression, neural connection, and receiver-operating characteristic (ROC) curves. FINDINGS: First-year and second-year patient-group characteristics and biochemical markers did not differ. The overall frequency of clinically significant fibrosis was 40% (138 patients). The most informative markers were: alpha2 macroglobulin, alpha2 globulin (or haptoglobin), gamma globulin, apolipoprotein A1, gamma glutamyltranspeptidase, and total bilirubin. The areas (SD) under the ROC curves for the first-year (0.836 [0.430]) and second-year groups (0.870 [0.340]) did not differ (p=0.44). With the best index, a high negative predictive value (100% certainty of absence of F2, F3, or F4) was obtained for scores ranging from zero to 0.10 (12% [41] of all patients), and high positive predictive value (>90% certainty of presence of F2, F3, or F4) for scores ranging from 0.60 to 1.00 (34% [115] of all patients). INTERPRETATION: A combination of basic serum markers could be used to substantially reduce the number of liver biopsies done in patients with chronic HCV infection.


Assuntos
Biomarcadores/sangue , Hepatite C Crônica/complicações , Cirrose Hepática/diagnóstico , Apolipoproteína A-I/sangue , Bilirrubina/sangue , Biópsia , Feminino , Haptoglobinas/análise , Hepatite C Crônica/patologia , Humanos , Fígado/patologia , Cirrose Hepática/virologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade , alfa-Macroglobulinas/análise , gama-Globulinas/análise , gama-Glutamiltransferase/sangue
19.
Gut ; 46(2): 277-82, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10644325

RESUMO

BACKGROUND/AIMS: A study was undertaken of liver biopsy samples from 229 consecutive patients with alcoholic or hepatitis C virus related cirrhosis who were prospectively followed until January 1996 to evaluate the influence of liver iron content on survival and the occurrence of hepatocellular carcinoma. METHODS: Hepatic iron content was measured with a validated semiquantitative score, and its predictive value for survival and the occurrence of hepatocellular carcinoma was assessed. RESULTS: 130 patients had detectable iron at enrollment. During follow up (57 (28) months), 95 patients died and 39 patients developed hepatocellular carcinoma. No significant relation was found between hepatic iron and the occurrence of hepatocellular carcinoma. Conversely, the presence of iron was predictive of death in alcoholic patients (p = 0.007) by the log rank test but not in patients with hepatitis C virus related (p = 0.71) or mixed (p = 0.98) cirrhosis. The predictive value of hepatic iron content in patients with alcoholic cirrhosis was confirmed by the Cox model using either a binary coding (p = 0.009; relative risk = 2.27; 95% confidence interval 1.2 to 4.19) or the continuous values (p = 0.002). CONCLUSIONS: These results suggest that hepatic iron enhances liver lesions caused by alcohol but not those caused by hepatitis C virus.


Assuntos
Hepacivirus , Hepatite C Crônica/metabolismo , Ferro/análise , Cirrose Hepática Alcoólica/metabolismo , Fígado/química , Carcinoma Hepatocelular/metabolismo , Progressão da Doença , Feminino , Seguimentos , Hepatite C Crônica/mortalidade , Humanos , Fígado/virologia , Cirrose Hepática Alcoólica/mortalidade , Neoplasias Hepáticas/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Taxa de Sobrevida
20.
Pathol Biol (Paris) ; 47(9): 966-73, 1999 Nov.
Artigo em Francês | MEDLINE | ID: mdl-10609277

RESUMO

Pediatric liver diseases usually manifest as jaundice, hepatomegaly, ascites or edema and can reflect a metabolic or nonmetabolic condition. In unconjugated hyperbilirubinemia, hemolysis can be distinguished from transient or inherited glucuronidation deficiencies. Jaundice with conjugated hyperbilirubinemia should suggest extrahepatic bile duct obstruction (requiring immediate surgery) or intrahepatic mechanical or metabolic cholestasis. Hepatomegaly or hepatocellular necrosis suggests diseases characterized by hepatocyte damage or overload. Appropriate investigations and a painstaking physical examination are essential to establish the diagnosis and to identify the cause, since immediate treatment is needed in some cases.


Assuntos
Hepatopatias , Pediatria , Colestase , Hepatomegalia , Humanos , Hiperbilirrubinemia , Lactente , Recém-Nascido , Fígado/patologia , Hepatopatias/diagnóstico , Hepatopatias/terapia , Necrose
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