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J Tichet

Publications and source records attributed to J Tichet.

At least 55 records · Page 3Linked to original sources
PubMed1994

Serum alanine aminotransferase measurement as a guide to selective testing for hepatitis C during medical checkup.

The efficiency of elevated serum alanine aminotransferase values for selecting subjects to be tested for hepatitis B or C infections in a large French population undergoing a medical checkup was investigated. For 5 consecutive weeks, serum alanine aminotransferase values were controlled in 9044 subjects; 308 subjects (202 males) were selected with alanine aminotransferase levels 1.2-fold above the normal value (58 iu/l for men, 34 iu/l for women). For each selected case, an age- and sex-cross-matched control was included. Of the 308 subjects with elevated alanine aminotransferase values, one was HBsAg positive and 15 (seven males) were anti-HCV positive. All anti-HCV sera tested by enzyme immunoassay were also positive by three immunoblots and 11/15 (73%) were HCV-RNA positive by reverse transcription-polymerase chain reaction. Of the 308 control subjects, two were HBsAg positive and four (two males) were weakly anti-HCV positive by enzyme immunoassay. Only one weakly anti-HCV positive serum was reactive by one immunoblot and all were HCV-RNA negative. This study shows the usefulness of alanine aminotransferase screening to detect hepatitis C virus infection in the general French population. Many of the anti-HCV positive subjects detected in this study were not aware of their hepatitis C virus seropositivity (12/15) or that they were viremic (11/15). Use of this low-cost assay will considerably reduce the number of subjects to be tested for hepatitis C virus serological status and therefore the cost. It may make possible the investigation of large populations by setting up public health programs to detect and treat hepatitis C virus. Hepatitis C virus infected subjects detected in these programs could benefit from medical follow up, including antiviral therapy.

Adolescent↗
PubMed1994

[Rubella vaccine coverage and seroprotection in 11-year-old children in the Indre-et-Loire department].

To determine the current rates of vaccination and seroprotection against rubella of French preadolescents, a survey was conducted among children in their first year of junior schools of the department of Indre-et-Loire (prefecture: Tours). The rate of vaccination against rubella during infancy or childhood was 58.8% for the girls and 9.4% for the boys, as compared with 99.5% for both sexes for the vaccination against diphteria, tetanus and poliomyelitis. An effective seroprotection against rubella was found more frequently in girls than in boys (90.4% vs 78%), and was also more frequent among vaccinated than non vaccinated preadolescents (98% vs 77%). From these data the authors recommend that a stronger policy of vaccination against rubella should be be adopted, ie. order to obtain the eradication of rubella in France.

Antibodies, Viral↗
PubMed1993

Prevalence and significance of hepatitis C virus (HCV) viremia in HCV antibody-positive subjects from various populations.

Hepatitis C virus (HCV) infection is currently assessed by detection of antibodies to HCV with immunoassays. However, in the absence of an in vitro system to isolate the virus, or an immunoassay to identify HCV antigen in blood, an ongoing acute or chronic HCV infection can be diagnosed only by detection of HCV RNA by polymerase chain reaction. We used a reverse transcription-nested polymerase chain reaction to detect an HCV 5' noncoding viral RNA sequence in serum specimens collected from anti-HCV-positive individuals belonging to different risk groups and compared the results with those obtained with a prototype recombinant immunoblot assay (Chiron HCV SIA prototype recombinant immunoblot assay [RIBA]) containing four different viral peptides (c22, c33c, c100, and NS5). The prevalence of HCV viremia ranged from 25.9% in HCV antibody-positive blood donors to 92% in HCV antibody-positive hemophiliacs. Elevated alanine aminotransferase values in HCV antibody-positive patients were clearly associated with viremia. Ninety-six percent of HCV RNA-positive patients reacted to two viral antigens or more, compared with only 64% of HCV RNA-negative patients. Contrary to previous reports, HCV viremia was not associated with either the presence or the absence of a particular antibody specificity. The newly introduced NS5 peptide did not improve the sensitivity or specificity of the RIBA. Although 20% of the patients in our study whose sera reacted to all of the antigens were HCV RNA negative, the positive predictive value of a RIBA considered positive by the manufacturer (two or more bands), was rather high (78%) and may allow suspicion of viremia in EIA2 enzyme-linked immunosorbent assay-positive patients.

Alanine Transaminase↗
PubMed1992

[Food habits of adults in France. Epidemiological data].

During the year 1990, 43,440 men and women aged from 17 to 69 years accepted to fill the NAQA questionnaire (18 items) on feeding habits, as part of a routine health examination. The frequency of consumptions and the amounts of food consumed are reported here according to sex. Mean energy intake was 2,586 kcal for men and 1,758 kcal for women and consisted of: fats 102 and 74 g respectively, sucrose 60 and 35 g, proteins 95 and 72 g, alcohol 24 and 4 g, calcium 1,128 and 982 mg and cholesterol 457 and 341 mg. For both men and women 16 percent and 16.8 percent respectively of non-alcohol intakes were made of proteins and 38 percent and 38.6 percent of lipids. Calcium intake was low in 7.5 percent of the subjects. Data analysis by sex and 10-year age groups showed a decrease of fats and sucrose rations and stability of protein rations as the subjects were growing older. These results were similar to those of a recent survey performed with the food history technique. The data obtained by us are an interesting source of information for Public Health epidemiology. They are compared with those found in the literature and discussed.

Adolescent↗
PubMed1992

Islet cell antibodies in normal French schoolchildren.

Islet-cell antibodies have been reported to be of predictive value for the future development of Type 1 (insulin-dependent) diabetes in first degree relatives of diabetic patients with the risk increasing in these subjects with the islet-cell antibodies titre. However, very little is known about islet-cell antibodies in background populations. Sera (n = 8363) from schoolchildren (6-17 years) in the French background population were screened for the presence of islet-cell antibodies by the indirect immunofluorescence technique. Islet-cell antibodies greater than 4.5 Juvenile Diabetes Foundation units were found in 150 sera (prevalence rate 1.8%; 95% confidence interval 1.5-2.1%). Only 17 sera demonstrated islet-cell antibody titre greater than or equal to 24 JDF units. No particular feature was found to be significantly different between islet-cell antibody-positive and islet-cell antibody-negative children (age, family history of diabetes, fasting plasma glucose, insulin autoantibodies). A second blood sample was obtained from 80 of 150 islet-cell antibody positive children after a mean interval of 8 months. Only 11 sera became less than 4.5 JDF units with islet-cell antibody titres being stable in the remaining sera, including the high-titre positive sera (greater than or equal to 24 JDF units). HLA-DQB typing was performed by restriction mapping techniques in 80 islet-cell antibody-positive, in 93 islet-cell antibody-negative and in 213 Type 1 diabetic children. The distribution of the susceptibility alleles (DQB1-Asp57-negative) was not significantly different between islet-cell antibody-positive and islet-cell antibody-negative children.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

[Risk markers of insulin-dependent diabetes in the normal population].

Risk factors for IDD have been studied in relatives of patients, in whom the risk is far higher than in the children from the background population. Several factors have been identified as the genetic background at the HLA level (DR and DQ regions) and autoantibodies like islet cells antibodies (ICA) and insulin autoantibodies (IAA). 8,363 sera from schoolchildren (age 6-17 yr) have been tested for the presence of ICA. 150 sera (1.8%) were found positive; the prevalence rate of high ICA titres (> or = 20 uJDF) was very low: 0.2%. ICA titres remained stable over a 8 mth follow-up period. IAA have been measured on the first 2,000 sera and the prevalence rate was 1.2%. Only 3 sera were found positive for the two antibodies, one coming from a diabetic girl. The distribution of the susceptibility alleles at the DQ-HLA region was similar among the ICA-positive and ICA-negative children.

Adolescent↗
PubMed1992

[Seroepidemiology of hepatitis A in six departments in West-Central France in 1991].

Antibodies to hepatitis A virus were sought for among residents of 6 "départements" of West-Central France during a routine medical check up provided by the national health insurance system to all affiliated persons. Among them 5,641 subjects (aged 6 to 60) were randomly selected to a sample size of 256 +/- 15 male or female subjects for each five-year age group. Anti-HAV were detected in 51% of the screened population. The prevalence was less than 5% in the 6-15 age group and increased by successive steps to exceed 90% in the subjects over 50. The highest increase was observed between the 26-30 (39%) and the 31-35 (57%) age groups. This study confirms the influence of socio-economical factors on the anti-HAV prevalence rate. Factors such as profession or scholar education were previously known, but the housing conditions and especially the number of siblings were identified in our present report. In relation to this low prevalence of anti-HAV among young adults, one may fear an increase of overt hepatitis cases which are known to be more frequent in adults than in infants or children. Moreover any break in hygiene may expose the population to an epidemia. Only active immunization with a vaccine against hepatitis A could efficiently prevent these individual and community-related risks.

Adolescent↗
PubMed1991

Superiority of radiobinding assay over ELISA for detection of IAAs in newly diagnosed type I diabetic children.

OBJECTIVE: Liquid- or solid-phase assays have been used for insulin autoantibody (IAA) determination, and the method of IAA measurement has not been standardized. RESEARCH DESIGN AND METHODS: IAAs were determined by radiobinding assay (RBA) and enzyme-linked immunosorbent assay (ELISA) in two large age-matched groups of nondiabetic and newly diagnosed insulin-dependent (type I) diabetic children. RESULTS: Positivity for IAA by RBA (greater than or equal to nondiabetic mean + 3SD) was 2 of 178 (1.1%) and 55 of 173 (32%) in nondiabetic and diabetic children, respectively. Prevalence of IAA by RBA was significantly higher in the youngest age-group (63% between 0-4 yr). Positivity for IAA by ELISA was 1 of 178 (0.6%) and 8 of 169 (4.7%) in nondiabetic and diabetic children, respectively. Concordance rates between both assays were 0 of 3 (0%) in control subjects and 5 of 58 (8.6%) in diabetic children. CONCLUSIONS: We conclude that RBA is more appropriate than ELISA for IAA detection at the onset of the disease. In addition, because available data suggest that IAAs detected by RBA only are high-affinity antibodies, it is tempting to speculate that IAAs reflect a mature immune reaction against endogenous insulin.

Adolescent↗
PubMed1991

Body Mass Index variations: centiles from birth to 87 years.

This report provides Body Mass Index (weight/height2) values for the French population from birth to the age of 87 years. BMI curves increase during the first year, decrease until the age of 6, increase again up to 65 years and decrease thereafter. These variations reflect the total changes of fat body mass during life. The 50th centile values of Wt/Ht2 at the ages of 20, 40, 60, 80 years are 21.5, 24.6, 25.4, 24.4 kg/m2 for men and 20.6, 22.6, 24.1, 23.4 kg/m2 for women. The values for the 3rd, 50th and 97th centiles in the middle years are approximately 18, 24 and 32 kg/m2. Graphs for these and four other percentiles are plotted against age, and two other graphs summarising the variation and skewness of the Wt/Ht2 distribution are provided to calculate exact percentiles and Z-scores for individuals.

Aging↗
PubMed1990

[Validity of a short self-administered dietary questionnaire compared with a dietetic interview].

The dietary intakes of 250 men and women aged from 17 to 60 years were evaluated by means of a self-administered questionnaire. The purpose of this study was to develop and optimise a self-administered questionnaire deliberately reduced to 20 questions. The results were compared with those of a dietetic interview using the diet history method. The correlation coefficients for the main nutrients were determined by multivariate regression analysis and were found to fall in the 0.44-0.80 range (P less than 0.001). It is concluded that the self-administered questionnaire is satisfactory and valid as compared with the diet history method. The degree of validity reached is such that efficient epidemiological studies can be conducted at small cost, and the subjects at risk due to the main dietary errors listed in the contemporary French population can be detected.

Adolescent↗
PubMed1990

HLA-DQB 1 codon 57 and genetic susceptibility to type 1 (insulin-dependent) diabetes mellitus in French children.

Variations in the incidence rate of Type 1 (insulin-dependent) diabetes mellitus might relate to ethnic-specific genetic backgrounds. HLA-DQB 1 alleles were typed in 75 French diabetic children and 85 matched control children. Enzymatically-amplified DQB 1 exon 2 was hybridized with oligoprobes specific for the six most common alleles. Alleles coding for an Asp residue at position 57 in the DQ beta chain are strongly negatively associated with Type 1 diabetes in the French population. Nevertheless, one of the diabetic children was an Asp 57 homozygote (DQB 1.2/3.1). Among alleles coding for a residue other than Asp at position 57, alleles 3.2 and 2 (Ala 57) are positively associated with diabetes but not allele 1.1 (Val 57) which is less frequent in diabetic children than in control children. Heterozygosity for 2/3.2 alleles is the genotype most strongly associated with diabetes (Odds ratio = 52.9). Large comparative population studies will be necessary to determine whether the frequency of DQB 1 alleles positively associated with Type 1 diabetes (2 and 3.2) in a given ethnicity is related to its incidence rate in the same population.

Alanine↗
PubMed1990

Relationship between adiposity and food intake: an example of pseudo-contradictory results obtained in case-control versus between-populations studies.

Seemingly contradictory data support controversies concerning the relationships between food intake and illnesses. The present study of 1035 adults, aged 30-39 years, shows that (1) daily energy intake is not higher in obese than in non-obese people, (2) obesity is more prevalent in social groups where energy intake is higher. These pseudo-contradictory results can be reconciled on the basis of a constitution/environment interaction. A comparison of groups based on presence or absence of illness (obesity, hypertension, coronary heart disease (CHD), cancer, etc) shows that some people can develop risk factors, even though their feeding behaviour is normal. This result (no direct relationship) underlines differences in individual susceptibility. When comparisons are made between populations with different diets the results (direct relationship) express environmental factors. The hypotheses on behavioural contribution to the aetiology of certain diseases appears more clearly in between-population comparisons than in case-control studies. Results of comparisons between populations (if the hypotheses they suggest are confirmed by intervention studies) warrant prevention at the level of populations, while results of case-control studies justify particular prevention in subjects at risk.

Adipose Tissue↗
PubMed1990

[Health status of adolescents in the 7th grade at schools in Indre-et-Loire].

A survey of 1,316 pupils in the 7th grade in private or public schools in the department of Indre et Loire was conducted in order to establish the health status and needs of adolescents aged 12-15 years. Nutritional behavior, alcohol and tobacco consumption, obesity, hypertension, audio-visual disturbances, and dental status were the essential points of this survey. This study demonstrates the necessity of frequent and systematic health care supervision of adolescents, in an effort to detect and prevent or treat disturbances which may have long term adverse effects. The absence of such a structure in our medico-social armament is underlined along with the potential consequences that such a deficiency may have on the future adult generation.

Adolescent↗
PubMed1989

[Chronic non-insulin deficient hyperglycemia in children].

We report the clinical records of 45 children with abnormalities regarding glycemic regulation characterized by a non-insulin deficient hyperglycemia (NIDH), known under the different names of chemical diabetes, sub-clinical diabetes and more recently MODY. These 45 children belong to 31 families with 532 relatives comprising 137 cases of NIDH which could have been studied. The symptoms of this biochemical abnormality, the pathophysiology of which is not yet clearly understood, are the following: lack of clinical manifestations, except for a variable and intermittent glycosuria; constant abnormal glucose tolerance tests, above 97 percentiles of the reference value with some variations over time; normal immunoreactive insulin levels; percentage of glycosylated hemoglobin at the upper range of normal; dominant autosomal genetic transmission and no association with HLA markers like in insulin-dependent diabetes; lack of degenerative complications of the micro-angiopathic type, at least on these cases even after more than 30 years of follow-up; finally, no tendency towards insulin-dependent diabetes. The NIDH should not be confused with the slow and progressive beginning of insulin-dependent diabetes for which prolonged delay is needed to affirm the diagnosis. The frequency of the biochemical phenomena is about 1.8% of the cases of authentic diabetes mellitus occurring before the age of 15.

Adolescent↗
PubMed1986

Characteristics of children and adolescents with insulin-dependent diabetes mellitus participating in a summer camp educational program.

Clinical, biological and social characteristics were assessed in 456 children and adolescents participating in a summer camp for children with diabetes mellitus. In these subjects, aged from 7 to 18 years, the mean duration of the diabetes was five and a half years. They carried out their usual treatment under parental supervision, 31% of them being of rural origin. Mean glycosylated haemoglobin was approximately twice as high as a reference population (12.2% +/- 2.3, vs. 6.6% +/- 0.7) and was similar to that observed in various specialized hospitals. Factors which correlated with glycosylated haemoglobin included gender, school performance, vacation away from home, time spent watching television and practicing sport and eating patterns. This descriptive analysis gives some insight into the health status of the studied population. It represents the initial phase of a study to assess the efficacy of a diabetes educational programme for children and adolescents.

Adolescent↗