Search PubMed⌕ Search

Biomedical subjects

D Hemon

Publications and source records attributed to D Hemon.

At least 19 recordsLinked to original sources
PubMed2003

[Total elbow arthroplasty in rheumatoid arthritis using GUEPAR prosthesis].

PURPOSE OF THE STUDY: We report a retrospective analysis of 16 patients with rheumatoid arthritis treated with a total humero-ulnar and humero-radial GUEPAR prosthesis (GIII). MATERIAL AND METHODS: The GUEPAR III elbow prosthesis is an anatomic polyethylene-metal gliding prosthesis designed to maintain physiological valgus. Right and left models are available in two sizes. On the humero-ulnar side of the prosthesis, was associated with a radial head, born on an intramedullary metallic stem, that can be fit with several sizes of mobile polyethylene cups. The 16 GIII prostheses were implanted in 1997 to 2001 in accordance with the manufacturers instructions. Mean follow-up was 2 years. RESULTS: Before surgical treatment, all patients had moderate or severe but invalidating pain. The Mayo Clinic score was 33 points. The Larsen radiographic score was grade III (7 elbows) or grade IV (9 elbows). Patients were reassessed 1 to 5 years after implantation of the GIII (mean follow-up 2 years). At last follow-up the mean Mayo Clinic score had improved from 33 to 90 points. Outcome was considered excellent for 15 elbows and fair for 1. DISCUSSION: We review the indications for total elbow arthroplasty in patients with rheumatoid arthritis. Semi-constrained prostheses are useful and necessary for the treatment of elbows exhibiting massive destruction, but the use of minimally constrained prostheses such as the GUEPAR III is becoming increasingly widespread. We use the GUEPAR III for 70% of our patients, particularly those with rheumatoid arthritis.

Adult↗
PubMed2001

Environmental exposure to lead in a population of adults living in northern France: lead burden levels and their determinants.

As part of the assessment of a site in northern France polluted by metals from two smelters (in particular, lead, cadmium and mercury), a cross-sectional study was carried out which intended to estimate the levels of the lead burden of the adult population living on the site and the factors associated with these levels. The exposed zone included 10 municipalities in the Nord-Pas de Calais region, located in the vicinity of two non-ferrous metal smelters. The soils in these municipalities contained between 100 and 1700 ppm of lead. The non-polluted zone contained 20 municipalities from the same region, drawn randomly from those in the region of comparable size but free from any industrial lead exposure. The adult study population (301 men and 300 women) was stratified according to age, sex, employment status and exposure level. The inclusion criteria required subjects who were aged between 20 and 50 years and had been living in the exposed zone for at least 8 years; the exclusion criteria were pregnancy, cancer, kidney disease and diabetes. No more than 10% of the subjects participating could work at one of the two smelters. Data collection took place at home; visiting nurses interviewed subjects to complete a questionnaire and also took blood samples. The lead assay was performed by atomic absorption spectrometry. The geometric mean of the blood-lead levels was 74 microg/l, 95% CI = 69-80 among men and 49 microg/l, 95% CI = 46-53 among women. Blood-lead levels exceeding 100 microg/l were found among 30% of men and 12% of women. Several factors were associated with variation of the mean blood-lead level: the blood-lead level was significantly higher among the men for subjects living less than 1 km from the smelters (geometric mean x 1.3, 95% CI = 1.1-1.6), for those who drink alcoholic beverages (x 1.1, 95% CI = 1.0-1.2 for consumption of 30 g/day), those who smoke (x 1.2, 95% CI = 1.0-1.3 for 20 cigarettes/day), and for subjects with occupational exposure; among the women, for subjects living less than 1 km from the smelters (geometric mean x 1.5, 95% CI = 1.2-1.7), for those who drink alcohol (x 1.1, 95% CI = 1.1-1.2 for a daily consumption of 10 g), and for women living in a building constructed before 1948 (x 1.2, 95% CI = 1.0-1.4).

Adult↗
PubMed2001

Determinants of cadmium burden levels in a population of children living in the vicinity of nonferrous smelters.

This report covers part of the assessment of a site in northern France polluted by industrial metal emissions. Our objectives were to assess the cadmium burden in children aged 8 to 11 years and look for factors that affected it. A cross-sectional population-based study took place in 1996-1997 and included 400 children (200 in the metal-polluted area). The geometric mean of the blood cadmium (CdB) levels of children living on the polluted site was 0.51 microg/L (95% CI=[0.49-0.53]); that of the nonexposed children was 0.47 microg/L (95% CI=[0.45-0.49]) (P<0.01). The geometric mean of the urinary cadmium (CdU) levels of children living on the polluted site was 1.16 microg/g creatinine (95% CI=[1.01-1.34]); that of the nonexposed children was 0.99 microg/g creatinine (95% CI=[0.86-1.14]) (P=0.10). Mean CdB was higher among children within 4 km of a zinc smelter and consuming > or =500 ml of tap water daily (x1.34; 95% CI=[1.14-1.51]) compared with children living more than 4 km away and consuming <500 ml of tap water daily. Independently of this association, consumption of fish and shellfish (> or =once a week vs. or =once daily vs. <once daily) was associated with higher mean CdB levels, respectively: x 1.14; 95% CI=[1.07-1.21] and x 1.25; 95% CI=[1.04-1.50]. Neither sex nor age was associated with CdB. Mean CdU was associated with paternal occupational cadmium exposure.

Animals↗
PubMed2000

Environmental lead exposure in a population of children in northern France: factors affecting lead burden.

BACKGROUND: This study is part of the assessment of a site in northern France polluted by lead from industrial emissions. Our objectives were to look for the factors that influence lead burden in children aged 8-11 years. METHODS: A cross-sectional population-based study took place in 1996-97 and included 400 children (200 of whom lived on the metal-polluted site). RESULTS: The geometric mean of the blood-lead levels of children living on the polluted site was 39.5 microg/l (95% CI = 36.3-43.1); that of the non-exposed children was 30.6 microg/l (95% CI = 27.8-33.6) (P < 0.0001). Analysis of the variations in the mean blood-lead levels showed associations with: distance from the smelting plants (mean blood-lead level fell by a factor of 1/1.3 (95% CI = 1/1.2-1/1.4) for each km from the smelter over the range of 1-3 km and was constant thereafter) and consumption of tap water (when the water pipes were made of lead, the mean blood-lead level of children who drank tap water was twice as high (95% CI = 1.2-3.4) as that of children who did not). CONCLUSIONS: The children's blood-lead levels were essentially linked to two factors: proximity to the smelters and drinking tap rather than bottled water.

Body Burden↗
PubMed1995

Cancer risk among workers in biomedical research.

OBJECTIVE: This epidemiologic study was undertaken after a cluster of five cases of rare forms of cancer (bone sarcoma, non-Hodgkin's lymphoma) had been observed among biomedical research workers at the Pasteur Institute in Paris to ascertain whether their disease was connected with exposure during this research. METHODS: A mortality study included 3765 people who worked at the Pasteur Institute between 1971 and 1986 and were followed until the end of 1987. Within this cohort a nested case-referent study included 23 cases of cancer [non-Hodgkin's lymphoma (6), multiple myeloma (1), leukemia (3), pancreatic cancer (7), bone cancer (3), brain tumor (3)], and four referents per case, matched for gender and year of birth. RESULTS: Total mortality from cancer was less than expected, the standardized mortality ratio (SMR) being 72 for the men and 82 for the women. Among the women the proportion of pancreatic cancer cases was larger than expected [SMR 490, 95% confidence interval (95% CI) 158-1144], as was the number of brain cancer cases (SMR 239, 95% CI 48-696). Among the men, mortality from bone cancer was greater than expected (SMR 553, 95% CI 62-2006). In the nested case-referent study, more cases than referents had worked in the areas of molecular biology [odds ratio (OR) 7.1, 95% CI 1.5-33] and microbial genetics (OR 6.7, 95% CI 1.3-35). These cases especially included non-Hodgkin's lymphoma and bone cancer. Associated with this finding was the fact that more cases had used certain chemicals, including ethidium bromide, acrylamide, methylnitronitrosoguanidine and ethylmethanesulfonate, and radioactive compounds (essentially 32phosphorus). CONCLUSIONS: As the products used are potent genotoxicants, the present findings suggest that work in biomedical research might well involve an increased risk of certain types of cancer; this conclusion should be balanced by the fact that two of the five index cases were included in the mortality study and four in the nested case-referent study.

Academies and Institutes↗
PubMed1994

Incidence and risk factors for childhood brain tumors in the Ile de France.

A case-control study investigating risk factors for childhood brain tumors was conducted in the Ile de France (Paris region). During a 2-year period (1985-1987) 109 newly diagnosed cases were identified and, of these, 75 could be interviewed. In the same region, 113 population controls, frequency-matched for year of birth, were interviewed. Odds ratios adjusted for child's age and sex and for maternal age were estimated for each risk factor present in utero or during childhood by conditional logistic regression. Statistically significant associations were found for the following risk factors: farm residence, cat scratches, home treated with pesticides, passive smoking, family history of cancer, antihistamine intake. Intake of vitamin supplements during childhood was associated with a decrease in risk. This study is part of a multicentric case-control study coordinated by the International Agency for Research on Cancer and its results will be compared for consistency, and pooled with those of other centers using the same protocol.

Adolescent↗
PubMed1993

Occupational risks of bladder cancer in France: a multicentre case-control study.

The relationships between occupational risk factors in France and bladder cancer were assessed from a hospital-based case-control study conducted between 1984 and 1987 in five regions representing various industries, including mining, textile manufacture, metallurgy and the production of rubber and chemicals. The study concerned 765 cases (658 men and 107 women) and the same number of controls. Odds ratios (OR) adjusted for matching variables (age, place of residence and hospital), and tobacco smoking were estimated by unconditional logistic regression. A significantly increased risk of bladder cancer was observed among men employed in coal mining (OR = 2.42; 95% confidence interval (Cl) : 1.25-4.67) and the chemicals industry (OR = 2.36; 95% Cl : 1.23-4.53). Aircraft and ship's officers (OR = 11.8; 95% Cl : 1.46-95.7), managers (OR = 1.64; 95% Cl : 1.11-2.43) and street vendors (OR = 3.60; 95% Cl : 1.15-11.3) also had an increased risk. Among women, employment in the clothing industry was associated with a high OR (= 3.21; 95% Cl : 1.34-7.71). Assessment of individual exposures by a panel of industrial hygiene experts showed that significantly more cases than controls had been exposed to the following substances: chlorinated solvents (OR = 1.86; 95% Cl : 1.19-2.90), industrial oils and greases (OR = 1.44; 95% Cl : 1.10-1.89), welding fumes (OR = 1.40; 95% Cl : 0.98-2.01), coal dust (OR = 1.71; 95% Cl : 1.02-2.89) and metallic oxide dust (OR = 2.99; 95% Cl : 1.12-8.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1991

Lead-exposed workmen and fertility: a cohort study on 354 subjects.

A cohort study was conducted in a French battery factory in 1977-1982 to explore the relationship between occupational lead exposure and fertility. A total of 354 battery workers, divided into 229 lead-exposed subjects (corresponding with 886 person-years) and 125 non-lead-exposed subjects (corresponding with 598 person-years) were compared, in a person-year analysis, for the risk of infertility. Lead exposure, at any level of absorption, did not appear significantly associated with a reduction in fertility after controlling for potential confounders: age, French origin, educational level, number of children at start of the period, cigarette smoking and exposure to heat. The apparent inconsistency between our results and those of several studies involving biological data and semen analysis is partially explained by recent knowledge relating to predictive value on the pregnancy of semen abnormalities.

Adult↗
PubMed1991

Paternal exposure to mercury and spontaneous abortions.

The potential reproductive toxicity of mercury vapour was investigated by comparing the rate of spontaneous abortions among the wives of 152 workers occupationally exposed to mercury vapour with the rate among the wives of 374 controls in the same plant. The results indicate an increase in the rate of spontaneous abortions with an increasing concentration of mercury in the fathers' urine before pregnancy. At concentrations above 50 micrograms/l the risk of spontaneous abortion doubles (odds ratio (OR) = 2.26; 95% confidence interval (95% CI) = 0.99-5.23). Special care was taken to avoid bias in reporting abortions and known risk factors of spontaneous abortions do not seem to explain the results. Several biological mechanisms might account for them including, in particular, direct action of mercury on the paternal reproductive system and indirect toxicity to the mother or embryo through transport of mercury from the father. These indications could be of practical importance and should therefore be further documented.

Abortion, Spontaneous↗
PubMed1990

Occupational risk factors for upper respiratory tract and upper digestive tract cancers.

A case-control study was conducted to investigate occupational risk factors for upper respiratory and digestive tract cancers (nose, lips, buccal cavity, pharynx, and larynx) in the north of France. Two hundred and eighty three cases of histologically confirmed cancer in men treated during the first semester of 1983 at the Regional Cancer Institute were included in the study. Two controls per case were chosen from patients in the medical wards of the local general hospitals in the same geographical area as the case, who did not have cancer. Controls were individually matched for sex, age (+/- 18 months), ethnic group, area of residence, and smoking and alcohol drinking history. All subjects were questioned about occupations in which they had worked for at least 15 years. Odds ratios for major occupational categories were estimated using conditional logistic regression for matched samples. Significant associations were found between wood work and nasal cancer (four cases, no control) and farming and lip cancer (odds ratio 5.3, 95% confidence interval 1.1-26.8). Pharyngeal cancer was associated with the textile industry (OR 2.4, 95% CI 1.0-5.7) and the building industry (OR 2.0, 95% CI 1.1-3.9). Coal miners showed a threefold excess risk for cancer of the lip (4 cases, no control), buccal cavity (OR 3.5, 95% CI 1.1-11.8), and larynx (OR 3.2, 95% CI 1.1-9.7).

Alcohol Drinking↗
PubMed1989

Tobacco and bladder cancer in males: increased risk for inhalers and smokers of black tobacco.

Relationships between risk of bladder cancer and tobacco smoking were assessed from a hospital-based case-control study conducted in France from 1984 to 1987. Smoking history was analyzed for 954 male patients (477 cases and 477 controls). The odds ratio (OR) of bladder cancer was estimated at 3.95 for all smokers vs. non-smokers. The risk increased with duration of smoking and with average daily cigarette consumption, but there was a significant interaction between these 2 parameters, since the risk only increased with average daily consumption when the duration exceeded 20 years. Black tobacco consumption and inhaling were both found to double the risk when analyzed separately, but their respective effects appeared to interact, and an elevated risk for smokers of black tobacco was only observed among inhalers. Smokers of black and blond tobacco also differed in the way in which the risk evolved with time after cessation of smoking. The OR decreased faster after cessation of smoking among smokers of black tobacco than among smokers of blond tobacco, but the residual risk was higher 15 years after cessation among the former than among the latter.

Adult↗
PubMed1988

Gliomas and exposure to wood preservatives.

A case-referent study was undertaken to look for occupational risk factors among patients with glioma treated in a neurological hospital in Paris between 1975 and 1984. In the study group were 125 men with gliomas (aged less than or equal to 65) and 238 patients (also less than or equal to 65) admitted for non-neoplastic, non-malformative vascular diseases in the same department during the same period constituting the reference group. All diagnoses were confirmed by tomodensitometry. Information on occupational history was obtained from a postal questionnaire and from medical records. Comparison of cases and referents showed a significant excess risk among teachers (OR = 4.1) and a raised risk among wood workers (OR = 1.6). Four of nine cases of glioma who had been employed as wood workers reported that a colleague had suffered from glioma (those reports were confirmed by hospital records). None were reported among 11 referent wood workers. Using a complementary questionnaire on wood work, exposure assessment to wood preservatives and solvents showed that frequent exposure to organochlorine wood preservatives and to organic solvents occurred more often among cases than referent wood workers (p less than 0.10).

Adult↗
PubMed1986

Urine mutagenicity, chromosomal abnormalities and sister chromatid exchanges in lymphocytes of nurses handling cytostatic drugs.

The effects of handling antineoplastic drugs were examined in 17 nurses working in a pneumology department in a hospital in the Paris area. Twenty-five others in the same department who were not handling such drugs acted as controls. Exposure to antineoplastic drugs was evaluated by questionnaire and by assessment of urine mutagenicity. The cytogenetic repercussions of exposure were assessed by examining sister chromatid exchanges and chromosomal abnormalities in circulating lymphocytes. The urine of the exposed nurses was significantly more mutagenic than that of the controls. No cytogenetic abnormalities were revealed in the exposed subjects since both these and the control nurses exhibited similar frequencies of chromosomal abnormalities and similar average numbers of sister chromatid exchanges in circulating lymphocytes. However, in smokers, the urine was significantly more mutagenic compared to that of nonsmokers, chromosomal abnormalities were twice as frequent, and the number of sister chromatid exchanges was significantly larger. Comparison of these results with the findings of other authors suggests that the moderate exposure to antineoplastic drugs prevailing in this pneumology department (i.e., an average of about 11 infusions per week) does not cause detectable cytogenetic abnormalities even though it significantly increases urine mutagenicity.

Antineoplastic Agents↗
PubMed1986

[Epidemiology of occupational risks: methodological problems].

The main methodological problems encountered in occupational epidemiology are related to the particularity of the risk factors concerned. It is necessary to account for the "Healthy Worker Effect" in the design, analysis and interpretation of surveys since the very presence of workers at particular jobs is related to their health. In cohort studies, it is necessary to have precise knowledge of the work environment corresponding to different jobs as exposure information is generally not individual, objective and continuously recorded. In case-control studies also, information on occupational exposures is a key issue, not only from the point of view of differential bias but also because exposure that is too loosely defined leads to dilution and reduced accuracy.

Adolescent↗
PubMed1985

New data on the in-situ position of the inactive X chromosome in the interphase nucleus of human fibroblasts.

The in situ spatial distribution of nucleolus-organizing-region (NOR) bearing chromosomes in relation to the inactive X chromosome was studied during interphase in human fibroblasts. The respective positions of these chromosomes were examined in 30 growing and 32 resting fibroblasts from reconstructed nuclei, using nucleoli and the Barr body as ultrastructural markers. Experimental values for the distance between the nucleoli and the Barr body were estimated by their coefficient of closeness and compared to the uniform distribution. The following results were obtained: the distribution patterns for the two populations of nuclei were similar, the distribution of the NOR-bearing chromosomes in relation to the inactive X chromosome varied and differed significantly from a uniform distribution, and in many cases the Barr body was observed to be in a juxta-nucleolar position. The internal distribution revealed by this study is compared with the data in the literature, especially with the conflicting data obtained by other methods used to determine the interphase arrangement of chromosomes. The relationship between interphase and metaphase arrangements such as can be deduced with these methods, is discussed in relation to the mechanisms of the formation of metaphase plates or chromatid translocations.

Cell Nucleolus↗
PubMed1984

In situ arrangement of nor-bearing chromosomes in the interphase nucleus of Aotus trivirgatus.

The spatial organization of the two nucleolus-organizing region (NOR)-bearing chromosomes during interphase was studied in Aotus trivirgatus fibroblasts, using nucleoli as ultrastructural markers. Their distribution was examined by measuring the distances between them in 30 reconstructed nuclei, and comparing these experimental values with the theoretical ones obtained by simulation. Results were as follows: (1) the nucleoli are arranged in a polarized manner inside the nucleus; (2) the nucleoli are tightly bound to the nuclear envelope at two opposites sites; (3) the distance between the two nucleoli is variable, and is shorter than it would be if the two nucleoli were distributed at random. These findings indicate that the NOR-bearing chromosomes are fixed at the nuclear envelope in two opposite areas. They are also consistent with the hypothesis that each chromosome occupies a separate domain inside the nucleus. They can be interpreted according to the model in which chromosome arrangement within the interphase nucleus is based on the separation of the diploid complement into two independent haploid sets.

Animals↗
PubMed1984

[Oral contraceptives and cardiovascular mortality].

Several epidemiological studies have demonstrated at the individual level an elevated risk of cardiovascular death for women who have been using oral contraceptives. Nevertheless, there has been no detectable increase in the number of cardiovascular deaths during the last fifteen years in countries where the use of oral contraceptives has become widespread. In this paper, we have tried to analyse this apparent contradiction and to discuss the causal nature of the relationship linking oral-contraceptives and cardiovascular death. For this purpose, we present a bibliographical summary of the relevant studies as well as an analysis of the trend in cardiovascular deaths among women in France from 1968 to 1975.

Adult↗