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1.
Cancer Radiother ; 24(2): 88-92, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32156457

ABSTRACT

PURPOSE: The optimal dose in esophageal cancer patients treated with definitive chemoradiation (CRT) remains debated. We herein report on the dosimetric results, treatment-related toxicities and long-term outcomes of escalated dose up to 60Gy delivered with intensity-modulated radiotherapy (IMRT). MATERIALS AND METHODS: All consecutive patients that received a definitive CRT>50Gy for an unresectable esophageal carcinoma between 2010 and 2015 were retrospectively evaluated for this study. Methodology included data base search, delayed toxicity grading, statistical testing including frequency analysis and survival analysis. RESULTS: A total of 51 patients were irradiated for a squamous cell carcinoma (86.3%) or an adenocarcinoma (13.7%). The median age at diagnosis was 62 years. Seven patients were simultaneously irradiated for another synchronous primary tumor. Forty-six patients (90.2%) received concurrent platin-based chemotherapy. The median prescribed doses were 60Gy (54-66) and 48Gy (44.8-56) delivered in 30 (27-35) fractions to the high and the low risks PTV respectively. The mean dose delivered to the lungs was 11.4Gy (IC 95%: 4.8-19.8), the median volumes receiving up to 20Gy (V20) and 30Gy (V30) were 13.5% (3.0-46.0) and 4.6% (0.7-19.8) respectively. The mean dose delivered to the heart was 13.9Gy (IC 95%:0.3-31.3) with a median V40 of 3.3% (0.0-25.0). One treatment-related death occurred within days after RT completion (neutropenic aplasia). After a median follow-up of 2.7 years (95% CI: 1.9-4.3), the 2-year overall survival, disease free survival and loco-regional control rates were 53.6%, 42.0% and 72.8% respectively. Delayed treatment related-toxicities ≤grade 3 occurred among 25 patients (62.5%) mostly esophageal stricture (79.2%). CONCLUSION: We demonstrated in this study that dose escalation using IMRT in combination with platin-based chemotherapy as a definitive treatment for esophageal carcinoma is safe and results in higher loco-regional and control survival when compared to previously reported data.


Subject(s)
Adenocarcinoma/therapy , Carcinoma, Squamous Cell/therapy , Chemoradiotherapy/methods , Esophageal Neoplasms/therapy , Radiation Tolerance , Radiotherapy, Intensity-Modulated/methods , Adenocarcinoma/mortality , Adenocarcinoma/pathology , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/pathology , Chemoradiotherapy/adverse effects , Disease-Free Survival , Dose Fractionation, Radiation , Esophageal Neoplasms/mortality , Esophageal Neoplasms/pathology , Esophageal Stenosis/etiology , Female , Fluorouracil/administration & dosage , Heart/radiation effects , Humans , Leucovorin/administration & dosage , Lung/radiation effects , Male , Middle Aged , Organoplatinum Compounds/administration & dosage , Organs at Risk/radiation effects , Radiotherapy, Intensity-Modulated/adverse effects , Retrospective Studies , Time Factors , Treatment Outcome
2.
Cancer Radiother ; 21(3): 216-221, 2017 May.
Article in French | MEDLINE | ID: mdl-28461029

ABSTRACT

Radiotherapy's main skin toxicities are now well-separated, acute (acute radiation dermatitis) or chronic complications (chronic radiation dermatitis, induced cutaneous carcinoma, aesthetic sequelae). Exceptionally, radiotherapy may induce, by isomorphic reaction or Koebner's phenomenon, some specific dermatosis. In this article, we report five new observations of these unusual complications of radiation therapy, occurring in very variable time after breast irradiation and remaining strictly localized in the irradiated field (cutaneous mastocytosis, Sweet syndrome, lichen planus, vitiligo). These cases emphasize the need to realize a systematic histological exam if any atypical skin lesion appears after radiotherapy, even long after.


Subject(s)
Breast Neoplasms/radiotherapy , Radiation Injuries/etiology , Skin Diseases/etiology , Adult , Aged , Aged, 80 and over , Female , Humans
3.
Transplant Proc ; 46(10): 3314-8, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25498043

ABSTRACT

BACKGROUND: We measured the functional and metabolic status of hearts submitted to normothermic ischemia before preservation through the use of an ex vivo pig heart model to assess the feasibility of donation after cardiac death (DCD) in heart transplantation. METHODS: Ten pigs were separated into 2 groups: control (n = 6, brain-dead group) and DCD (n = 4, heart donation after cardiac death). In the control group, hearts were excised 20 minutes after the brachiocephalic trunk cross-clamping and were immediately reperfused. In DCD, hearts were excised 20 minutes after exsanguination and asphyxia, stored in the Centre de Résonance Magnétique Biologique et Médicale (CRMBM) solution for 2 hours, and then were reperfused. Cardioplegic arrest was induced with the use of 1 L of CRMBM solution (4°C) and the heart was reperfused for 60 minutes through the use of an ex vivo perfusion system in Langendorff mode with normothermic autologous blood. During reperfusion, functional parameters were analyzed. Biochemical assays were performed in myocardial effluents and freeze-clamped hearts. RESULTS: No electromechanical activity was found in DCD compared with control. Creatine kinase (CK) was higher at 2 minutes of reperfusion in DCD versus control (P = .005). Adenosine triphosphate was lower in DCD versus control (P = .0019). Malondialdehyde, an oxidative stress index, was present only in DCD. The nitric oxide (NO) pathway was impaired in DCD versus control, with lower eNOS expression (P < .0001) and total nitrate concentration content (P = .04). CONCLUSIONS: We reported no cardiac functional and metabolic recovery in the DCD group after normothermic ischemia and reperfusion, which indicates that a single immersion of the cardiac graft during storage does not provide an optimal protection. New strategies in heart preservation are necessary for recruiting heart donation after cardiac death.


Subject(s)
Heart Arrest, Induced/methods , Heart Transplantation , Myocardial Reperfusion Injury/prevention & control , Tissue and Organ Procurement/methods , Animals , Disease Models, Animal , Heart , Myocardium/pathology , Swine
4.
J Infect Dis ; 205(5): 718-24, 2012 Mar 01.
Article in English | MEDLINE | ID: mdl-22238471

ABSTRACT

We performed a genome-wide association study comparing a cohort of 144 human immunodeficiency virus (HIV type 1-infected, untreated white long-term nonprogressors (LTNPs) with a cohort of 605 HIV-1-infected white seroconverters. Forty-seven single-nucleotide polymorphisms (SNPs), located from class I to class III major histocompatibility complex (MHC) subregions, show statistical association (false discovery rate, <0.05) with the LTNP condition, among which 5 reached genome-wide significance after Bonferonni correction. The MHC LTNP-associated SNPs are ordered in ≥4 linkage disequilibrium blocks; interestingly, an MHC class III linkage disequilibrium block (defined by the rs9368699 SNP) seems specific to the LTNP phenotype.


Subject(s)
Disease Progression , Genes, MHC Class I/genetics , HIV Infections/genetics , HIV-1 , Polymorphism, Single Nucleotide , DNA-Binding Proteins/genetics , Gene Frequency , Genome-Wide Association Study , Histocompatibility Antigens Class I/genetics , Humans , Major Histocompatibility Complex/genetics , RNA, Long Noncoding , RNA, Untranslated , Time Factors , Transcription Factors/genetics
5.
Biometrics ; 66(1): 301-9, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19432790

ABSTRACT

Pharmacovigilance systems aim at early detection of adverse effects of marketed drugs. They maintain large spontaneous reporting databases for which several automatic signaling methods have been developed. One limit of those methods is that the decision rules for the signal generation are based on arbitrary thresholds. In this article, we propose a new signal-generation procedure. The decision criterion is formulated in terms of a critical region for the P-values resulting from the reporting odds ratio method as well as from the Fisher's exact test. For the latter, we also study the use of mid-P-values. The critical region is defined by the false discovery rate, which can be estimated by adapting the P-values mixture model based procedures to one-sided tests. The methodology is mainly illustrated with the location-based estimator procedure. It is studied through a large simulation study and applied to the French pharmacovigilance database.


Subject(s)
Adverse Drug Reaction Reporting Systems/statistics & numerical data , Algorithms , Data Interpretation, Statistical , Decision Support Systems, Clinical , False Positive Reactions , Pattern Recognition, Automated/methods , Humans
6.
Cell Mol Biol (Noisy-le-grand) ; 55 Suppl: OL1208-14, 2009 Dec 20.
Article in English | MEDLINE | ID: mdl-20018145

ABSTRACT

Maintenance of nitric oxide (NO) homeostasis is an important concept for myocardial protection. Here, we have investigated the NO pathway by analysing total nitrate concentration (NOx) and NO synthase (NOS) isoforms expression as well as the myocardial integrity by lactate dehydrogenase and creatine kinase contents in the rat heart graft arrested by CRMBM solution, submitted to 3 hr cold ischemia in the same solution and 24 hr blood reperfusion following heterotopic abdominal heart transplantation. NOx level was similar to baseline value after ischemia and significantly increased after 24 hr reperfusion. NOS isoforms expression was highly modulated after cold ischemia followed by blood reperfusion. Endothelial NOS expression was decreased after ischemia but restored after 24 hr reperfusion. Neuronal NOS expression was drastically decreased after ischemia and 24 hr reperfusion. Inducible NOS protein was present only after 24 hr reperfusion. Cold ischemia induced a severe loss of creatine kinase without any modification after blood reperfusion. In conclusion, we show here that CRMBM solution did not increase NO production during ischemia but induced an enhanced synthesis of NO during reperfusion which may be related to restoration of endothelial NOS expression and/or induction of inducible NOS expression.


Subject(s)
Cold Temperature , Heart Transplantation , Myocardial Reperfusion , Nitric Oxide Synthase Type III/genetics , Nitric Oxide Synthase Type II/genetics , Nitric Oxide Synthase Type I/genetics , Nitric Oxide/biosynthesis , Animals , Gene Expression Regulation, Enzymologic , Heart/physiopathology , Isoenzymes/genetics , Isoenzymes/metabolism , Male , Myocardial Ischemia/metabolism , Nitric Oxide/analysis , Nitric Oxide Synthase Type I/metabolism , Nitric Oxide Synthase Type II/metabolism , Nitric Oxide Synthase Type III/metabolism , Rats , Rats, Inbred Lew , Tissue and Organ Harvesting
7.
Am J Physiol Endocrinol Metab ; 292(5): E1474-82, 2007 May.
Article in English | MEDLINE | ID: mdl-17264228

ABSTRACT

Although it has been suggested that the skeletal muscle mitochondrial uncoupling protein-3 (UCP3) is involved in regulating energy expenditure, its role is still poorly understood. In the present study, we aimed at investigating noninvasively, using magnetic resonance techniques, metabolic changes occurring in exercising muscle as a result of capsiate treatment, which has been previously linked to UCP3 upregulation. We showed that capsiate ingestion strongly reduced UCP3 gene expression in rat gastrocnemius muscle. This large underexpression was accompanied by a significant increase in the rate of mitochondrial ATP production and phosphocreatine level both at rest and during muscle stimulation. Similarly, the stimulation-induced ATP fall and ADP accumulation were significantly less after capsiate administration than in untreated rats. The larger oxidative ATP production rate could not be explained by a proportional decrease in the anaerobic component, i.e., glycolysis and phosphocreatine breakdown. In addition, the mechanical performance was not affected by capsiate administration. Finally, the plasma free fatty acid (FFA) level increased in capsiate-treated rats, whereas no significant change was observed after muscle stimulation in the control group. Considering the corresponding enhanced UCP3 mRNA expression occurring in the control group after muscle stimulation, one can suggest that changes in FFA level and UCP3 mRNA expression are not mechanistically correlated. Overall, we have shown that capsiate administration induced a UCP3 downregulation coupled with an increased mitochondrial ATP synthesis, whereas the muscle force-generating capacity was unchanged. This suggests that a decrease in muscle efficiency and/or additional noncontractile ATP-consuming mechanisms result from UCP3 downregulation.


Subject(s)
Analgesics, Non-Narcotic/pharmacology , Capsaicin/analogs & derivatives , Ion Channels/metabolism , Mitochondria, Muscle/metabolism , Mitochondrial Proteins/metabolism , Muscle, Skeletal/metabolism , Adenosine Diphosphate/metabolism , Adenosine Triphosphate/metabolism , Animals , Capsaicin/pharmacology , Down-Regulation/drug effects , Electric Stimulation , Energy Metabolism , Fatty Acids, Nonesterified/blood , Female , Hydrogen-Ion Concentration , Ion Channels/biosynthesis , Ion Channels/genetics , Magnetic Resonance Spectroscopy , Mitochondria, Muscle/drug effects , Mitochondrial Proteins/biosynthesis , Mitochondrial Proteins/genetics , Muscle, Skeletal/drug effects , Phosphocreatine/metabolism , Rats , Rats, Sprague-Dawley , Uncoupling Protein 3
8.
Radiat Prot Dosimetry ; 119(1-4): 222-5, 2006.
Article in English | MEDLINE | ID: mdl-16644989

ABSTRACT

Alpha-alumina is a useful thermoluminescence (TL) dosemeter. The knowledge of its behaviour under irradiation is thus of primary importance. The purpose of this paper is to characterise the radiation damage produced by swift krypton ions using various experimental methods, namely TL, optical absorption, fluorescence and electron paramagnetic resonance (EPR). After ion irradiation, the TL intensity is shown to decrease, whereas the optical absorption rises in the whole studied wavelength range. These two phenomena seem to be related to one another. Furthermore, optical absorption measurements highlight the appearance of new absorption bands probably owing to oxygen vacancies. Induced defects are also observed in the EPR spectra of irradiated pellets. They are likely related to electronic holes trapped on oxygen ions. The concentration of these defects increases with ion fluence and fluorescence measurements indicate that some pre-existing defects such as F2(2+) centres follow the same trend up to approximately 4.1 x 10(13) ions cm(-2).


Subject(s)
Aluminum Oxide/chemistry , Aluminum Oxide/radiation effects , Heavy Ions , Hot Temperature , Krypton , Thermoluminescent Dosimetry/methods , Dose-Response Relationship, Radiation , Materials Testing , Radiation Dosage , Thermoluminescent Dosimetry/instrumentation
9.
Transplant Proc ; 37(10): 4553-5, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16387168

ABSTRACT

Recent studies have suggested the involvement of the nitric oxide (NO) pathway in ischemia-reperfusion injury related to cardiac transplantation. Herein, we assessed the NO pathway by quantifying endothelial (e) and inducible (i) nitric oxide synthase (NOS) expression and total NOS activity in a rat heart transplant model during cold ischemia with Celsior cardioplegia and reperfusion. Experiments were performed using a modified Lewis-Lewis heterotopic abdominal heart transplantation with 3 or 6 hours of ischemia with or without 1 hour of blood reperfusion. NOS expression and activity were determined using Western blotting and colorimetric assays, respectively, on freeze-clamped hearts after ischemia without (n = 10) or with reflow (n = 12) compared with basal values. Hearts submitted to 3 hours of ischemia and 1 hour of reperfusion showed a postischemic rate pressure product of 5190 +/- 3047 mm Hg/min (reversible ischemia), but no contractility was observed after 6 hours of ischemia. eNOS protein levels were lower after 3 hours of ischemia compared with the basal value (P = .0005) and were further decreased after 6 hours of ischemia (P < .0001 versus basal value and P = .0018 versus 3 hours of ischemia). Reperfusion did not further decrease eNOS protein levels. iNOS protein was not detected in any condition. NOS activity was increased after 3 hours of ischemia versus basal value (P = .0065) but not after 6 hours of ischemia without any effect of reperfusion. We concluded that eNOS expression was altered during ischemia and the amplitude of the alteration depended on the duration of ischemia. Reversible ischemia was associated with increased NOS activity at the end of ischemia with no variation at reperfusion.


Subject(s)
Heart Transplantation/physiology , Nitric Oxide/physiology , Reperfusion Injury/physiopathology , Animals , Blood Pressure , Models, Animal , Myocardial Contraction , Myocardial Ischemia/physiopathology , Nitric Oxide Synthase/genetics , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type III/metabolism , Rats , Rats, Inbred Lew , Time Factors , Transplantation, Isogeneic
10.
Biol Neonate ; 87(2): 121-6, 2005.
Article in English | MEDLINE | ID: mdl-15539769

ABSTRACT

To investigate the influence of maternal smoke exposure on neonatal and maternal antioxidant status, 39 mothers who were active smokers, 14 mothers exposed to environmental tobacco smoke (ETS), 17 controls, and their newborns were included in a prospective, controlled study. Plasma total antioxidant capacity, measured as total radical-trapping antioxidant parameter (TRAP) and ferric reducing antioxidant power (FRAP), and concentrations of specific antioxidants were measured in cord and in maternal blood. A similar, significant increase in ceruloplasmin concentration was observed in neonates born to actively smoking mothers and in those born to ETS exposed mothers. Uric acid and TRAP concentrations were significantly increased in ETS-exposed newborns and their mothers, compared to newborns and mothers from the active smoking and no-exposure groups with a trend towards increased uric acid, TRAP and FRAP concentrations being observed in the active smokers group. Neonatal and maternal antioxidant concentrations correlated significantly, except for ceruloplasmin. Cord blood vitamin A, E and C concentrations were unaffected by smoke exposure. These results show that maternal active smoking as well as ETS exposure significantly affect neonatal and maternal antioxidant status.


Subject(s)
Antioxidants/analysis , Fetal Blood/chemistry , Maternal-Fetal Exchange , Smoking/adverse effects , Tobacco Smoke Pollution/adverse effects , Adult , Ascorbic Acid/blood , Ceruloplasmin/analysis , Female , Ferric Compounds/chemistry , Free Radicals/chemistry , Humans , Infant, Newborn , Pregnancy , Prospective Studies , Uric Acid/blood , Vitamin A/blood , Vitamin E/blood
11.
Rev Epidemiol Sante Publique ; 52(6): 523-37, 2004 Dec.
Article in French | MEDLINE | ID: mdl-15741915

ABSTRACT

BACKGROUND: When analysing data which simultaneously implicate a large number of statistical tests, one of the main problems is to take into account the multiplicity of these tests. The huge amount of comparisons done in studies of which the aim is to detect, using microarray, genes whose transcriptional changes are related to a biological or clinical outcome leads to a renewed interest for the multiple comparisons problem. However, this problem concerns many other fields such as psychometry, epidemiology, genetics. RESULTS: First, we introduce the multiple comparison framework. Then, we present the main procedures based on a global error rate called the "Family Wise Error Rate" (FWER) and those based on a false discovery rate expectancy (the "False Discovery Rate" (FDR) and the "positive False Discovery Rate" (pFDR)). Next, we apply the different procedures on a real dataset from a breast carcinoma study. Finally, we discuss the main results and we present guidelines for the use of these procedures.


Subject(s)
Gene Expression Profiling/methods , Oligonucleotide Array Sequence Analysis/methods , False Positive Reactions , Genotype , Humans , Phenotype , Sequence Analysis/methods
12.
Eur J Clin Chem Clin Biochem ; 33(8): 503-12, 1995 Aug.
Article in English | MEDLINE | ID: mdl-8547434

ABSTRACT

We compared data obtained with the Kodak Ektachem and Hitachi 717 Analysers and HPLC from 83 neonates under phototherapy. Total bilirubin values determined with the Kodak and Hitachi are in good agreement, but we observed a large discrepancy in the results for conjugated (Kodak) and direct (Hitachi) bilirubin. HPLC revealed that all the samples contained configurational isomers, while only 7.7% and 30.8% contained conjugated bilirubin and structural isomers, respectively. We developed a device for the specific and quantitative production of configurational or structural isomers, by irradiation with blue or green light. In vitro, total bilirubin values are coherent for the routine analysers in the presence of configurational or structural isomers. With configurational isomers, unconjugated bilirubin (Kodak) is lower than total bilirubin (Kodak), and conjugated bilirubin (Kodak) is always equal to zero, so the apparatus gives a false positive response for delta bilirubin. In contrast, the direct bilirubin (Hitachi) is constant. Furthermore, in the presence of structural isomers, unconjugated bilirubin (Kodak) is unexpectedly higher than total bilirubin (Kodak), conjugated bilirubin (Kodak) is proportional to the quantity of these isomers, and direct bilirubin (Hitachi) is constant. The contribution of photoisomers in bilirubin measurements is discussed.


Subject(s)
Bilirubin/blood , Jaundice, Neonatal/therapy , Phototherapy , Bilirubin/chemistry , Chromatography, High Pressure Liquid , Humans , Infant, Newborn , Isomerism , Jaundice, Neonatal/blood , Kinetics , Light , Molecular Structure , Regression Analysis , Spectrophotometry
13.
Eur J Clin Chem Clin Biochem ; 31(3): 115-9, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8490056

ABSTRACT

The binding of bilirubin was analysed in the serum of a patient with unusual myeloma. This patient presented an acquired Von Willebrand's disease due to the presence of a ternary complex formed by one molecule of myeloma immunoglobulin G and two molecules of albumin (Harlé et al. La Presse Médicale 19, 1661-1664 (1990)). The binding characteristics of bilirubin--number of sites (n) and association constants (k)--were estimated in the serum of the proband, and compared with those of purified human serum albumin and pooled normal human serum. The data suggest that complex formation between albumin and immunoglobulin induces abnormal bilirubin binding in the patient's serum, which becomes apparent when the bilirubin/albumin ratio exceeds 1.3. This abnormal binding may be due to conformational changes of the albumin molecule in the complex. The greatly increased number of lower affinity binding sites for bilirubin is certainly due to the abnormally high concentration of myeloma immunoglobulin G in the serum of the patient.


Subject(s)
Bilirubin/blood , Immunoglobulin G/blood , Myeloma Proteins/metabolism , Serum Albumin/metabolism , von Willebrand Diseases/blood , Humans , Male , Middle Aged , Protein Binding
14.
Transplantation ; 54(4): 599-603, 1992 Oct.
Article in English | MEDLINE | ID: mdl-1412750

ABSTRACT

A comparative study of 24 hr preservation at 4 degrees C of excised rat livers with Euro-Collins and hydroxyethyl starch-free University of Wisconsin (UWm) solutions has been conducted based on the assessment of (1) the cellular energy status determined by 31P NMR spectroscopy and (2) cellular injury estimated from the loss of purine compounds (inosine, hypoxanthine, xanthine, and uric acid) during cold ischemia and reperfusion measured by HPLC, the leakage of intracellular enzymes, and the modifications of parenchyma established by light microscopy. Recovery of nucleosides di- and triphosphate was greater in the UWm group (80 +/- 6% vs. 58 +/- 6%) while inorganic phosphate formation was comparatively reduced. During hypothermic storage, the UWm groups generated a higher amount of inosine and hypoxanthine (in relation to the presence of adenosine in the protective solution) while no xanthine or uric acid was detected due to the inhibitory effect of allopurinol. Conversely, large quantities of xanthine and uric acid were found in the reperfusate of the EC group, pinpointing the cytotoxic role of oxygen-derived free radicals in the generation of cellular damage, as also illustrated by a higher aspartate aminotransferase leakage in the EC group (devoid of allopurinol and glutathione. Light microscopy indicated no histological alterations in the UWm group and mild alterations in the EC group that showed ballooning of hepatocytes (no lactobionate and raffinose in EC) and an alternation of clarifications and eosinophilic condensations. This study clearly confirms and illustrates the overall superiority of UWm solution in liver transplant preservation.


Subject(s)
Hypertonic Solutions , Liver , Organ Preservation Solutions , Solutions , Tissue Preservation/methods , Adenosine , Allopurinol , Animals , Aspartate Aminotransferases/analysis , Glutathione , Hypothermia, Induced , Insulin , L-Lactate Dehydrogenase/analysis , Magnetic Resonance Spectroscopy , Male , Microscopy , Purines/metabolism , Raffinose , Rats , Time Factors
15.
Cell Mol Biol ; 38(3): 273-80, 1992 May.
Article in English | MEDLINE | ID: mdl-1319283

ABSTRACT

Histochemical and cytochemical methods induce a loss of endoplasmic reticulum (ER) membrane integrity in hepatocytes. In order to evaluate the degree of ER membrane integrity, glucose-6-phosphatase (G6P-A) was localized in light and electron microscopy using glucose-6-phosphate (G6P) and mannose-6-phosphate (M6P) as substrates. In case of ER membrane alteration, M6P diffuses inside the ER and is hydrolysed by a non-specific phosphohydrolase. G6P and M6P hydrolysis was quantified with image analysis methods. In light microscopy, the ratio of reaction of M6P hydrolysis/G6P hydrolysis gave 75% of non specific reaction. In electron microscopic study this ratio was about 30%. These results showed that enzyme localization methods in electron microscopy produced less ER membrane alteration than light microscopic methods.


Subject(s)
Endoplasmic Reticulum/enzymology , Glucose-6-Phosphatase/analysis , Endoplasmic Reticulum/metabolism , Glucose-6-Phosphatase/metabolism , Glucose-6-Phosphate , Glucosephosphates/metabolism , Histocytochemistry , Humans , Image Processing, Computer-Assisted , Liver/enzymology , Liver/ultrastructure , Mannosephosphates/metabolism , Microscopy , Microscopy, Electron
16.
Presse Med ; 19(36): 1661-4, 1990 Nov 03.
Article in French | MEDLINE | ID: mdl-2147267

ABSTRACT

The authors report an exceptional case of complex monoclonal dysglobulinaemia characterized by cryoglobulinaemia, pseudoanalbuminaemia and acquired type 1 Von Willebrand's disease. All these biological abnormalities are consecutive to the formation of molecular complexes in vivo. These complexes have also been found in vitro between albumin immunoglobulins G.


Subject(s)
Cryoglobulinemia/complications , Dysgammaglobulinemia/complications , Immunoglobulin M/deficiency , Serum Albumin/deficiency , von Willebrand Diseases/complications , Electrophoresis, Cellulose Acetate , Humans , Immunoglobulin M/analysis , Male , Middle Aged , Serum Albumin/analysis
17.
J Histochem Cytochem ; 38(11): 1565-9, 1990 Nov.
Article in English | MEDLINE | ID: mdl-2170502

ABSTRACT

Glucose-6-phosphatase (G6Pase) is a multicomponent system that catalyzes G6P hydrolysis. To determine the specificity of the histochemical reaction of G6Pase, we investigated the inhibitory effect of diethyl pyrocarbonate (DEPC), a specific and very effective inhibitor of the phosphohydrolase component of the G6Pase system, in normal human liver. The inactivation of the histochemical enzymatic activity by DEPC was monitored by determining the mean brightness of the microscopic image and the histogram of light intensity distributions. The results obtained indicate that the histogram is more sensitive than the mean brightness to variations of enzymatic activities, and that the percent of pixels brighter than a convenient level is directly proportional to DEPC concentration. This study indicates that DEPC can be used as an efficient inhibitor of the histochemical reaction of G6Pase.


Subject(s)
Diethyl Pyrocarbonate/pharmacology , Glucose-6-Phosphatase/antagonists & inhibitors , Histocytochemistry/methods , Image Processing, Computer-Assisted/methods , Liver/enzymology , Enzyme Activation/drug effects , Female , Glucose-6-Phosphatase/metabolism , Humans , Liver/cytology , Liver/drug effects , Male , Middle Aged
18.
Chemotherapy ; 36(2): 91-7, 1990.
Article in English | MEDLINE | ID: mdl-2311445

ABSTRACT

The effects of 'third-generation' cephalosporins and penicillin analogues on the concentrations of total unconjugated bilirubin, unbound bilirubin and erythrocyte-bound bilirubin were determined in blood samples. This study was performed, in vitro, at two bilirubin/albumin molar ratios and at various concentrations of antibiotics. The most effective displacers, considering the three methods, were antibiotics tightly bound to albumin: ceftriaxone and cefotetan. Cefoperazone, which is bound to albumin as tightly as these two antibiotics, caused no significant increase in unbound bilirubin but should be considered as a displacer drug on the basis of the variations of erythrocyte-bound bilirubin and total bilirubin. We suggest that drug interaction on bilirubin-albumin binding be investigated by several methods.


Subject(s)
Anti-Bacterial Agents/metabolism , Bilirubin/metabolism , Erythrocytes/metabolism , Serum Albumin/metabolism , Anti-Bacterial Agents/blood , Anti-Bacterial Agents/pharmacology , Bilirubin/blood , Drug Interactions , Erythrocytes/analysis , Humans , Protein Binding/drug effects , Serum Albumin/analysis , beta-Lactams
20.
J Antimicrob Chemother ; 19(6): 823-9, 1987 Jun.
Article in English | MEDLINE | ID: mdl-3610909

ABSTRACT

Determination of 'free' bilirubin, erythrocyte-bound bilirubin and unconjugated bilirubin was used to test the effects of ceftriaxone on the binding of bilirubin to albumin. This study, performed on blood samples from icteric neonates, showed that the addition of ceftriaxone produced an increase of free bilirubin and erythrocyte-bound bilirubin and a decrease of unconjugated bilirubin. Ceftriaxone displays a significant displacing effect at concentrations obtained during therapeutic use and should be used with caution in high-risk jaundiced infants.


Subject(s)
Bilirubin/metabolism , Ceftriaxone/pharmacology , Erythrocytes/metabolism , Humans , Infant, Newborn , Serum Albumin/metabolism
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