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C Janot

Publications and source records attributed to C Janot.

At least 37 records · Page 2Linked to original sources

[Comparative study of immunologic consequences of autotransfusion and homologous transfusion in lung cancer surgery].

A study was carried out to determine the effects of transfusion with either autologous or homologous blood in 35 patients with lung cancer undergoing lung surgery. The patients were randomly allocated to two groups, "allo" receiving homologous blood (n = 10), and "auto" receiving autologous blood only (n = 13). A third control group included the patients (n = 12) who had not required any blood. In patients of "auto" group, two blood removals of 7 ml.kg-1 each were performed, provided their haemoglobin concentration was over 110 g.l-1 and their haematocrit over 34%. The following parameters were studied at t-1 (the day of inclusion), t0 (just before surgery and transfusion), t1 (one week after surgery), and t2 (one month later): haematocrit and haemoglobin concentration; IgG, IgA and IgM concentrations; polymorphonuclear and neutrophil leucocyte and lymphocyte numbers, lymphocyte subpopulations (CD4/CD8), activated natural killers (NK), polymorphonuclear leukocyte chemotaxis and chemoluminescence. Anaesthesia and surgery initiated initiated an early decrease in immunity in all three groups. The immune profile, and its time course in patients who received autologous blood only was similar to that of those who were not transfused at all. On the other hand, homologous blood transfusion seems to modify the recipient's non specific immune system. In group "allo", a decrease occurred in the number of auxiliary lymphocytes CD4, an increase in suppressor lymphocyte numbers CD8, with an increase in the CD4/CD8 ratio, and no increase in NK activity. These data suggest that autologous transfusion is well tolerated in cancer patients undergoing surgery.

Adult↗

Assessment of screening tests for transfusion-associated non-A non-B hepatitis.

Non-A non-B hepatitis is the most common serious sequela of blood transfusion, and its screening has become an essential goal of blood transfusion centers. Before 1989, two surrogate screening tests (for alanine aminotransferase and for antibody to hepatitis B core antigen) were used; in 1989, a direct test for the antibody to hepatitis C virus (the main agent of this hepatitis) was developed. The French National Agency for the Development of Medical Evaluation undertook an investigation to determine the optimal prevention strategy for posttransfusion non-A and non-B hepatitis (PTH). A detailed literature review was performed, complemented by expert group opinion. The performance of each test was derived indirectly by calculating the number of cases of PTH averted by each test. Hepatitis C virus testing is probably the most promising strategy, but different policies can be developed given the uncertainties of scientific data. Cost considerations should be taken into account in identifying the best screening strategy.

Alanine Transaminase↗

[Seroprevalence of hepatitis C antibodies among blood donors. Study of second generation ELISA and RIBA tests and surrogate markers].

Between March and November 1991, prevalence of hepatitis C antibodies was evaluated in 60,960 blood donors from the North-East of France. Using a second generation ELISA, 424 donors (0.69%) were reactive, with no significant difference between males (0.69%) and females (0.70%). Among these 424 donors, respectively 137 (32.3%), 86 (20.3%) and 201 (47.4%) were reactive, indeterminate or nonreactive by a second generation RIBA (RIBA-2) (Recombinant Immunoblot Assay). Donors with a high ELISA ratio (> or = 4) were significantly more likely to have a reactive RIBA-2. Of the 1906 donors with anti-HBc positivity (3.12%), 44 had a reactive ELISA; of these, respectively 27, 12 and 5 had a reactive, indeterminate and nonreactive RIBA. Of the 1201 donors (1.97%) with increased serum ALAT (alanine-amino-transferase) levels (> or = 2N), 42 had a positive ELISA; of these, respectively 35, 2 and 5 had a reactive, indeterminate and nonreactive RIBA. Of the 54 donors with both indirect markers, nine had a reactive ELISA; the same nine donors had a reactive RIBA. These data show that donors with both surrogate markers and a reactive ELISA are very likely to have a positive RIBA. Seventy-seven (18.16%) of the 424 donors with a reactive ELISA had at least one surrogate marker; 67 of these donors (30.04%) were among the 223 donors with a reactive ELISA and a reactive or indeterminate RIBA.

Biomarkers↗

[Hepatitis C virus].

Hepatitis C Virus, major causative agent of parenterally transmitted non-A non-B hepatitis was identified by Choo et al. in 1988 using molecular biology technologies. This virus contains a positive stranded RNA genome, it has been shown to have a small diameter. These structure and properties suggest that HCV shares many features in common with Pestiviruses and Flaviviruses. After many years of research, two major objectives were reached: -the identification of viral genome and the main purified viral polypeptide derived from recombinant yeast. Major information were recently appearing about the nucleotide sequences of different isolates coming from US, Europe and Japan; -the preparation of specific tool (ELISA anti-HCV) for detection of circulating HCV antibodies.

Genome, Viral↗

[Analytical study of the Abbott and Ortho tests for screening and confirmation of anti-HCV antibodies. Le groupe de Travail "Hépatites virales" de la Société Française de Transfusion Sanguine].

Anti-HCV systematic screening on blood donation was mandatory in France since first of March 1991. Two laboratories (Ortho-Chiron and Abbott) have introduced in Europe successively two kinds of hepatitis C positive diagnosis with 1st and 2nd generation ELISA screening and confirmatory assays. The aim of this multicentric study was to evaluated the sensibility and specificity of these tests. For that, they used 10,090 blood sera. As a result we have seen that the new "second generation" screening assays have a higher sensitivity without less of specificity for the confirmatory tests.

Antigens, Viral↗

[European Acute Transfusion Hepatitis Interferon Study (EATHIS)].

Since 1989, a prospective, multicentric and collaborative study, named European Acute Transfusion Hepatitis Interferon Study (EATHIS), involving 16 blood centres in France is coordinated by a task force in collaboration with the Viral Hepatitis and Recipients working groups of the French National Society of Blood Transfusion. A phase of recipient screening may be completed by a therapeutic interferon protocol. Among 1,476 transfused recipients receiving an average of 4.4 blood components, 1,011 were followed up at least four months. The incidence of non-A, non-B post-transfusion hepatitis (PTH) was varying from 0.1 to 6% at the different locations. Out of 15 hepatitis cases, 10 were diagnosed as post-transfusional. These preliminary data indicate a reduced incidence of PTH, with a mean of 1% for the period 1989-1991. It emphasises the importance of a transfusion vigilance program including follow up and testing for transaminases and specific viral markers.

Adolescent↗

[Hepatitis C virus and transfusion: policy regarding the donation and the donor. Groupe "Hépatites Virales" de la Société Nationale de Transfusion Sanguine].

Hepatitis C virus (HCV) discovery and introduction of anti-HCV antibodies screening in blood transfusion imply the necessity of a good blood donations and blood donors policy. Detection of a seropositivity during the screening must be completed with a confirmatory test. The results are directly used to inform donors and define the blood products policy. Donors with positive results on confirmatory test are discarded and have physical and biological examinations in hepatology. Individuals with indeterminate or negative results must be retested for the HCV serology. Furthermore, because of a rapid improvement in the fields of technology, diagnosis and therapy of HCV, an adaptation of the policy is necessary.

Blood Donors↗

Epidemiology of anti-HCV antibodies in France. Viral Hepatitis Study Group of the French Blood Transfusion Society.

The aim of this large survey which covered 173,038 unselected blood donors, was to determine the seroprevalence of anti-HCV antibodies and surrogate markers (ALT and anti-HBc) in France. The results revealed a frequency of 0.63% of anti-HCV positive donors. The correlation with surrogate markers was very poor but since we know nothing about the infectivity of anti-HCV negative donations, screening of surrogate markers must still be performed to prevent post-transfusional hepatitis.

Alanine Transaminase↗

[Evaluation of the quality of the principal kits to identify HBs antigen used in French blood transfusion centers. "Viral hepatitis" group of the SNTS].

The aim of this study is the evaluation of the main kits used for the HBs Ag screening in French blood donors. Eight ELISA or RIA kits were evaluated. The specificity was assessed by testing samples from unselected blood donors. Repeatedly reactive sera were confirmed by a neutralisation test using an anti-HBs polyclonal antibody. The specificity expressed by the false positive reactions was lower than 0.1% for the ELISA and RIA kits. Sensitivity was assessed by the study of a panel of 16 HBs Ag specimens (ad and ay subtypes) with titres ranging from 0.05 to 1.80 ng/ml; all were tested in duplicate. Differences in sensitivity were observed according to the kits and procedures used. Some kits have a better sensitivity than RIA which is no longer the most sensitive technique. Such a study and a permanent control of each lot of HBs Ag commercial kit allow an improvement of reagents quality.

Antibody Specificity↗

[Practical approach to the discovery of serum markers for infection by hepatitis B virus (HBs antigen or anti HBc antibody). Hypertransaminasemia or the two anomalies in a blood donor].

By now in France HBV seric markers (Ag HBs and Ac HBc) and transaminases level (ALT) screenings are compulsory by law in blood donors. People whose blood donation is discarded should be informed. A clinical, epidemiological and virological survey of such donors is required to differentiate healthy Ag HBs carriers and patients suffering from hepatitis B (who may eventually be treated). Similar guidelines may be recommended for the blood donors presenting high transaminases level without HBV seric markers in order to find a cause for such impaired biochemical tests: overweight, alcohol, drug consumption, auto-immune liver disease, genetic disorder, Non-A, Non-B, Non-C hepatitis....

Alanine Transaminase↗

Recombinant immunoblot assay first and second generations on 732 blood donors reactive for antibodies to hepatitis C virus by ELISA. The Hepatitis Study Group of the French Society of Blood Transfusion.

A comparison between recombinant immunoblot assay hepatitis C virus (HCV) first generation (RIBA-1) and second generation (RIBA-2) was made on 732 blood donors reactive by anti-HCV ELISA (Ortho Diagnostics System) by the Hepatitis Study Group of the French Society of Blood Transfusion. RIBA-2 results were correlated with ELISA ratio and ALT levels. The number of both reactive and nonreactive samples was higher with RIBA-2 than with RIBA-1, 252 (34%) compared to 224 (31%) for reactive samples, and 404 (55%) compared to 307 (42%) for nonreactive samples. C 22-3 and C 33-c reactivities were observed in 96 and 91% of the reactive samples, respectively. A total of 76 samples (11%) remained indeterminate by RIBA-2, 84% of them reacting only on C 100-3 antigen. A clear relationship between RIBA-2 results and both ELISA ratio and alanine aminotransferase (ALT) levels was demonstrated: 20% of samples with normal ALT level and 10% of samples with low ELISA ratio were reactive when 91% of samples with ALT greater than 2N and 69% of samples with high ELISA ratio were reactive. The totality of the 57 samples with both ALT greater than 2N and high ELISA ratio were reactive and 93% of samples with normal ALT level and low ELISA ratio were nonreactive.

Alanine Transaminase↗

[Serum antibodies against hepatitis C: study of 4,100 blood donors from the northeast of France].

Between June 1989 and February 1990 the prevalence of antibodies to hepatitis C virus (anti-HCV) was studied in blood donations from 4,100 donors tested in north east France. 37 samples were found reactive for anti-HCV (prevalence of anti-HCV: 0.90%) without any significant difference in sex (males: 0.94%; females: 0.87%) and age distributions. 178 (4.34%) of the 4,100 donors were found anti-HBc positive, 5 of these donors being anti-HCV positive (13.51% of all anti-HCV positive donors). 52 donors (1.27%) had raised alanine aminotransferase (ALT) levels (greater than or equal to 2 N: 2 times the M +/- 2 SD value): 3 were found anti-HCV positive (8.11% of all anti-HCV positive donors). Association of the 2 surrogate markers is poorly sensitive since it detects only 8 (21.62%; males: 4, females: 4) of all anti-HCV positive donors. Furthermore, it appears weekly specific since it discards 230 blood samples of which 222 (96.52%) were anti-HCV negative. The 2 surrogate markers are complementary to one another and none of the anti-HCV positive donors had both anti-HBc antibodies and raised ALT. The mean ALT level is significantly higher in anti-HCV positive donors as compared to seronegative (M +/- 1 SD: 51 +/- 82 U/l versus 24 +/- 17 U/l). In anti-HCV positive donors, a marginal (r = 0.34) though statistically significant (p less than 0.05) positive correlation was found between ALT level and anti-HCV ratio.(ABSTRACT TRUNCATED AT 250 WORDS)

Alanine Transaminase↗