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Papers by Christophe Doche
Clinical Chemistry and Laboratory Medicine, 1998
Annales de Toxicologie Analytique, 2011
Immuno Anal Biol Spec, 1997
La Presse Medicale, Feb 1, 2007
European journal of clinical chemistry and clinical biochemistry : journal of the Forum of European Clinical Chemistry Societies, 1996
The Roche Cobas Core automated enzyme immunoassay of antibodies against hepatitis B virus surface... more The Roche Cobas Core automated enzyme immunoassay of antibodies against hepatitis B virus surface antigen (anti-HBs) was evaluated using a protocol complying with the Société Française de Biologie Clinique guidelines. Results showed good precision (CV below 6 and 9% for intra- and inter-assay precision) and accuracy (according to the Paul-Ehrlich-Institute standard); the detection limit of the test was 2 IU/l. The manufacturer's specifications were confirmed and a satisfactory correlation (r = 0.901) was found with an automated method (IMx, Abbott) used for comparison.
Nouvelle revue française d'hématologie, 1992
The aim of this work is to reinvestigate the pentoxifylline (PTX) action on TNF alpha and IL-6 pr... more The aim of this work is to reinvestigate the pentoxifylline (PTX) action on TNF alpha and IL-6 production using a whole blood ex-vivo model. 5 healthy controls, 2 septic patients (4 samples) and 3 patients in septic shock (7 samples) have been studied. Our data confirm the inhibitory action of PTX on TNF alpha production in healthy controls. This inhibition is nearly complete for a PTX concentration of 10(-3) M. More surprisingly a suppressive activity of PTX on IL-6 secretion has been found both in controls and septic patients. On the 7 samples of the 3 patients with septic shock no TNF alpha production has been detected. Taken altogether, these observations suggest a potential role for PTX as a modulator of the major cytokines involved in the pathogenesis of septic shock.
Annales de biologie clinique
The aim of the study is to specify the pre-analytical conditions required for Down's syndrome... more The aim of the study is to specify the pre-analytical conditions required for Down's syndrome screening in first trimester by maternal serum markers. The concentration variation of both markers, hCGβ and PAPP-A, was analyzed at room temperature, at 4°C and during freezing-thawing cycles. Serum can be kept during 72h between 2 and 8°C with an acceptable bias of 5% for each marker. It can also undergo three freezing-thawing cycles without any variation of results. Preservation at room temperature (between 20 and 25°C) requires an analysis within 24h. From this study, writing recommendations enable to give a precise frame to pre-analytical processing and transport of blood samples, in a field where variations can lead to heavy therapeutic decisions.
Annales de biologie clinique
We report a case of an invisible monoclonal IgM on the profile of the serum electrophoresis carri... more We report a case of an invisible monoclonal IgM on the profile of the serum electrophoresis carried out by the Paragon CZE 2000 system. This case is about a 84 years old man followed for a Waldenström disease. The level of the monoclonal IgM given at the time of the preceding visit one year before was 10 g/L. The electrophoresis is reproduced in two other laboratories using respectively the Hydrasys and Capillarys techniques which have both shown the presence of the monoclonal peak. At this occasion the frequency of these anomalies of migration and the recommendations to avoid the erroneous interpretation of the electrophoresis are discussed. The vigilance and the competence of the biologist are essential to avoid this rare pitfall, induced by the new principle of the capillary electrophoresis.
Annales de biologie clinique
The reliability of the transfer of critical data between the biological laboratory and the clinic... more The reliability of the transfer of critical data between the biological laboratory and the clinical centres has to be reassessed. We have a legal constraint (GBEA and best practices) to make sure that the appropriate alert is issued for severe and urgent cases. In this paper, we present a study of the performances of data transfer tools, such as the comparison between regular phone and up to date available means like in line printers and network terminals. This paper focuses on the twenty-four hours duty in the hospital at the same level of reliability for alerts.
Annales françaises d'anesthèsie et de rèanimation, 2001
Annales de biologie clinique
Annales de biologie clinique
Annales de biologie clinique
Leukemia, 1997
In 93 newly diagnosed lymphoma patients, tumor necrosis factor alpha (TNF alpha) and its p55 solu... more In 93 newly diagnosed lymphoma patients, tumor necrosis factor alpha (TNF alpha) and its p55 soluble receptor (p55-sR), were prospectively determined in plasma by IRMA and ELISA methods respectively. These 93 patients included 31 patients with low grade lymphoma, 55 with intermediate or high grade lymphoma and 7 with Hodgkin's disease. Median TNF alpha plasma values were 20 pg/mL (range 5-380 pg/mL) in patients versus 7 pg/mL (range 4-9 pg/mL) in healthy control subjects. Presence of TNF alpha level equal or greater than 20 pg/mL was significantly associated with elevated LDH level, serum beta 2-microglobulin level > or = 3 mg/L, hemoglobin < or = 12 g/dL, Ann Arbor stage III or IV disease, and with bulky tumor. High level of TNF alpha was also associated, although less strongly, with B symptoms, poor performance status, and serum albumin < or = 35 g/L, yet it was not associated with change in acute phase protein levels. Levels of p55-sR were also markedly elevated in t...
Annales de biologie clinique
The introduction of the CRM 470 in 1993 (certified reference material for 14 serum proteins) and ... more The introduction of the CRM 470 in 1993 (certified reference material for 14 serum proteins) and its utilization by industrial companies for cross-calibrating their commercial standards has been an important break-through in protein standardization. This improvement has been clearly illustrated by the last national quality control survey performed in France in may 1995. At this time, about 60% of the 1,870 participants have already adopted the new standardization. The between-run precision (interlaboratory and intertechnique) has been considerably improved by the use of the new international standard (5.8 to 12.2% versus 10 to 24.1% before standardization); the same is true for accuracy. These results should convince the last reluctant laboratories to adopt the new standardization. Thus, it seems now possible to define reference ranges for serum proteins: this is the new task assigned to the Committee for Plasma Protein Standardization of the IFCC.
European cytokine network
The determination of cytokine levels in biological fluids by accurate and sensitive methods is an... more The determination of cytokine levels in biological fluids by accurate and sensitive methods is an absolute need to be able to define the involvement of these mediators in various clinical situations. To test if this goal was achieved with ELISA kits, a comparative study was undertaken using various commercial kits (6 for IL-2, 8 for IL-6 and 9 for TNF-alpha). The major aims of the work were to critically analyze the analytical performances of the kits and to illustrate some of the pitfalls the users may face. Substantial differences were noted in terms of sensitivity and behaviour of commercial standards versus international reference preparations. These results clearly illustrate the urgent need for a real standardization of immunoassays for cytokine quantitation.
Allergie et immunologie, 1995
Accurate and sensitive methods for the measurement of cytokines in biological fluids are an absol... more Accurate and sensitive methods for the measurement of cytokines in biological fluids are an absolute prerequisite for a proper use of these mediators in clinical practice. The authors describe the numerous molecular forms under which cytokines can possibly circulate. The potential influence of inhibitors (autoantibodies, soluble receptors) on cytokine assays is discussed. Blood collection for cytokines needs a particular attention to prevent a possible contamination by endotoxins which can trigger cytokines cellular production after sampling. If bioassays historically preceded immunoassays, these last techniques are now very popular, but there is an urgent need for standardisation between the different kits commercially available. In addition, in situ detection of cytokines using molecular biology is an helpful complementary technique to the measurement of circulating cytokines.
Immuno-analyse & Biologie Spécialisée
Clinical Chemistry and Laboratory Medicine, 1998
Annales de Toxicologie Analytique, 2011
Immuno Anal Biol Spec, 1997
La Presse Medicale, Feb 1, 2007
European journal of clinical chemistry and clinical biochemistry : journal of the Forum of European Clinical Chemistry Societies, 1996
The Roche Cobas Core automated enzyme immunoassay of antibodies against hepatitis B virus surface... more The Roche Cobas Core automated enzyme immunoassay of antibodies against hepatitis B virus surface antigen (anti-HBs) was evaluated using a protocol complying with the Société Française de Biologie Clinique guidelines. Results showed good precision (CV below 6 and 9% for intra- and inter-assay precision) and accuracy (according to the Paul-Ehrlich-Institute standard); the detection limit of the test was 2 IU/l. The manufacturer's specifications were confirmed and a satisfactory correlation (r = 0.901) was found with an automated method (IMx, Abbott) used for comparison.
Nouvelle revue française d'hématologie, 1992
The aim of this work is to reinvestigate the pentoxifylline (PTX) action on TNF alpha and IL-6 pr... more The aim of this work is to reinvestigate the pentoxifylline (PTX) action on TNF alpha and IL-6 production using a whole blood ex-vivo model. 5 healthy controls, 2 septic patients (4 samples) and 3 patients in septic shock (7 samples) have been studied. Our data confirm the inhibitory action of PTX on TNF alpha production in healthy controls. This inhibition is nearly complete for a PTX concentration of 10(-3) M. More surprisingly a suppressive activity of PTX on IL-6 secretion has been found both in controls and septic patients. On the 7 samples of the 3 patients with septic shock no TNF alpha production has been detected. Taken altogether, these observations suggest a potential role for PTX as a modulator of the major cytokines involved in the pathogenesis of septic shock.
Annales de biologie clinique
The aim of the study is to specify the pre-analytical conditions required for Down's syndrome... more The aim of the study is to specify the pre-analytical conditions required for Down's syndrome screening in first trimester by maternal serum markers. The concentration variation of both markers, hCGβ and PAPP-A, was analyzed at room temperature, at 4°C and during freezing-thawing cycles. Serum can be kept during 72h between 2 and 8°C with an acceptable bias of 5% for each marker. It can also undergo three freezing-thawing cycles without any variation of results. Preservation at room temperature (between 20 and 25°C) requires an analysis within 24h. From this study, writing recommendations enable to give a precise frame to pre-analytical processing and transport of blood samples, in a field where variations can lead to heavy therapeutic decisions.
Annales de biologie clinique
We report a case of an invisible monoclonal IgM on the profile of the serum electrophoresis carri... more We report a case of an invisible monoclonal IgM on the profile of the serum electrophoresis carried out by the Paragon CZE 2000 system. This case is about a 84 years old man followed for a Waldenström disease. The level of the monoclonal IgM given at the time of the preceding visit one year before was 10 g/L. The electrophoresis is reproduced in two other laboratories using respectively the Hydrasys and Capillarys techniques which have both shown the presence of the monoclonal peak. At this occasion the frequency of these anomalies of migration and the recommendations to avoid the erroneous interpretation of the electrophoresis are discussed. The vigilance and the competence of the biologist are essential to avoid this rare pitfall, induced by the new principle of the capillary electrophoresis.
Annales de biologie clinique
The reliability of the transfer of critical data between the biological laboratory and the clinic... more The reliability of the transfer of critical data between the biological laboratory and the clinical centres has to be reassessed. We have a legal constraint (GBEA and best practices) to make sure that the appropriate alert is issued for severe and urgent cases. In this paper, we present a study of the performances of data transfer tools, such as the comparison between regular phone and up to date available means like in line printers and network terminals. This paper focuses on the twenty-four hours duty in the hospital at the same level of reliability for alerts.
Annales françaises d'anesthèsie et de rèanimation, 2001
Annales de biologie clinique
Annales de biologie clinique
Annales de biologie clinique
Leukemia, 1997
In 93 newly diagnosed lymphoma patients, tumor necrosis factor alpha (TNF alpha) and its p55 solu... more In 93 newly diagnosed lymphoma patients, tumor necrosis factor alpha (TNF alpha) and its p55 soluble receptor (p55-sR), were prospectively determined in plasma by IRMA and ELISA methods respectively. These 93 patients included 31 patients with low grade lymphoma, 55 with intermediate or high grade lymphoma and 7 with Hodgkin's disease. Median TNF alpha plasma values were 20 pg/mL (range 5-380 pg/mL) in patients versus 7 pg/mL (range 4-9 pg/mL) in healthy control subjects. Presence of TNF alpha level equal or greater than 20 pg/mL was significantly associated with elevated LDH level, serum beta 2-microglobulin level > or = 3 mg/L, hemoglobin < or = 12 g/dL, Ann Arbor stage III or IV disease, and with bulky tumor. High level of TNF alpha was also associated, although less strongly, with B symptoms, poor performance status, and serum albumin < or = 35 g/L, yet it was not associated with change in acute phase protein levels. Levels of p55-sR were also markedly elevated in t...
Annales de biologie clinique
The introduction of the CRM 470 in 1993 (certified reference material for 14 serum proteins) and ... more The introduction of the CRM 470 in 1993 (certified reference material for 14 serum proteins) and its utilization by industrial companies for cross-calibrating their commercial standards has been an important break-through in protein standardization. This improvement has been clearly illustrated by the last national quality control survey performed in France in may 1995. At this time, about 60% of the 1,870 participants have already adopted the new standardization. The between-run precision (interlaboratory and intertechnique) has been considerably improved by the use of the new international standard (5.8 to 12.2% versus 10 to 24.1% before standardization); the same is true for accuracy. These results should convince the last reluctant laboratories to adopt the new standardization. Thus, it seems now possible to define reference ranges for serum proteins: this is the new task assigned to the Committee for Plasma Protein Standardization of the IFCC.
European cytokine network
The determination of cytokine levels in biological fluids by accurate and sensitive methods is an... more The determination of cytokine levels in biological fluids by accurate and sensitive methods is an absolute need to be able to define the involvement of these mediators in various clinical situations. To test if this goal was achieved with ELISA kits, a comparative study was undertaken using various commercial kits (6 for IL-2, 8 for IL-6 and 9 for TNF-alpha). The major aims of the work were to critically analyze the analytical performances of the kits and to illustrate some of the pitfalls the users may face. Substantial differences were noted in terms of sensitivity and behaviour of commercial standards versus international reference preparations. These results clearly illustrate the urgent need for a real standardization of immunoassays for cytokine quantitation.
Allergie et immunologie, 1995
Accurate and sensitive methods for the measurement of cytokines in biological fluids are an absol... more Accurate and sensitive methods for the measurement of cytokines in biological fluids are an absolute prerequisite for a proper use of these mediators in clinical practice. The authors describe the numerous molecular forms under which cytokines can possibly circulate. The potential influence of inhibitors (autoantibodies, soluble receptors) on cytokine assays is discussed. Blood collection for cytokines needs a particular attention to prevent a possible contamination by endotoxins which can trigger cytokines cellular production after sampling. If bioassays historically preceded immunoassays, these last techniques are now very popular, but there is an urgent need for standardisation between the different kits commercially available. In addition, in situ detection of cytokines using molecular biology is an helpful complementary technique to the measurement of circulating cytokines.
Immuno-analyse & Biologie Spécialisée