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D Caillaud

Publications and source records attributed to D Caillaud.

At least 19 recordsLinked to original sources

[Indoor radon exposure and lung cancer risk. Results of an epidemiological study carried out in France].

INTRODUCTION: Several epidemiological studies have indicated an increased risk of lung cancer associated with indoor radon exposure. As part of a large European project, a hospital based case-control study was carried out in four regions of France: Auvergne, Brittany, Languedoc-Roussillon and Limousin. MATERIAL AND METHODS: Individual data on demographic characteristics, residential history, smoking and occupational exposures were collected during face-to-face interviews. Radon concentrations were measured in each dwelling occupied by the subject during the 30-year period prior to the interview. RESULTS: 486 cases and 984 controls were included in the study. After adjustment for age, sex, region, smoking history and occupational exposure, the risk of lung cancer increased by 4% per 100 Bq/m(3), when considering cumulative exposure in the 30 years prior to diagnosis. CONCLUSION: The study indicates a positive association between lung cancer risk and indoor radon exposure. The risk estimate per unit of exposure is in agreement with other recently published indoor case-control studies.

Aged↗

Sequential two-line strategy for stage IV non-small-cell lung cancer: docetaxel-cisplatin versus vinorelbine-cisplatin followed by cross-over to single-agent docetaxel or vinorelbine at progression: final results of a randomised phase II study.

BACKGROUND: This phase II trial compared docetaxel-cisplatin (DC) with vinorelbine-cisplatin (VC), both as first-line therapy followed by cross-over at progression to single-agent vinorelbine or docetaxel in advanced non-small-cell lung cancer (NSCLC). METHODS: Overall, 115 patients received DC (docetaxel 75 mg/m(2) and cisplatin 100 mg/m(2) both on day 1, every 3 weeks, arm A1) and 118 VC (vinorelbine 30 mg/m(2)/week on days 1 and 8 and cisplatin 100 mg/m(2) on day 1, every 3 weeks, arm B1) for six cycles, and subsequently maintained by monotherapy with docetaxel (A1) or vinorelbine (B1) with cross-over on disease progression to vinorelbine 30 mg/m(2) days 1 and 8 (A2), or docetaxel 100 mg/m(2), day 1, both every 3 weeks (B2). The primary end point was overall response rate (ORR). RESULTS: Patient characteristics were balanced; median follow-up was 8.8 months. First-line response rate was 33.9% with DC and 26.3% with VC (P=0.20). In arms A1 and B1, respectively: duration of response was similar (8.2 versus 8.4 months); median time to progression was 5 months in both; median survival was 8 versus 9 months (P=0.38); 1-, 2- and 3-year survival was 36% versus 35%, 17% versus 10% and 13% versus 6% (P not significant). However, with a low number of long-term survivors, statistical significance was not reached. Overall, almost half of the patients crossed over to second-line therapy; there were no response with vinorelbine and 6 (11.2%) partial responses with docetaxel. Considering the safety profile, the occurrence of febrile neutropenia was 9.6% with DC and 26.3% with VC. Treatment-related mortality was 2.5% with DC and 8.5% with VC. CONCLUSIONS: The trend in favour of the DC arm in ORR, even though statistical significance was not reached, is consistent with previous reports. This study suggests an activity of first-line DC in advanced NSCLC, and that second-line vinorelbine does not provide additional clinical benefit. As already shown in other studies, the use of DC in first-line should provide a better percentage of long-term survivors, despite the absence of efficacy of the second-line in our study.

Adult↗

Long-term exposure to background air pollution related to respiratory and allergic health in schoolchildren.

BACKGROUND: The impact of air pollution on asthma and allergies still remains a debate. OBJECTIVE: Our cross-sectional study was intended to analyse the associations between long-term exposure to background air pollution and atopic and respiratory outcomes in a large population-based sample of schoolchildren. METHODS: Six thousand six hundred and seventy-two children aged 9-11 years recruited from 108 randomly schools in six French cities underwent a clinical examination including a skin prick test (SPT) to common allergens, exercise-induced bronchial reactivity (EIB) and skin examination for flexural dermatitis. The prevalence of asthma, allergic rhinitis (AR) and atopic dermatitis was assessed by a standardized health questionnaire completed by the parents. Three-year-averaged concentrations of air pollutants (NO2, SO2, PM10 and O3) were calculated at children' schools using measurements of background monitoring stations. RESULTS: After adjusting for confounders, EIB, lifetime asthma and lifetime AR were found to be positively related to an increase in the exposure to SO2, PM10 and O3. The adjusted odds ratios (aOR) per increase of 5 microg/m3 of SO2 was 1.39 (95% confidence interval (CI)=1.15-1.66) for EIB and 1.19 (1.00-1.41) for lifetime asthma. The aOR for lifetime AR per increase of 10 microg/m3 of PM10 was 1.32 (CI=1.04-1.68). Moreover, SPT positivity was associated with O3 (aOR=1.34; CI=1.24-1.46). Associations with past year symptoms were consistent, even if not always statistically significant. Results persisted in long-term resident (current address for at least 8 years) children. However, no consistent positive association was found with NO2. CONCLUSIONS: A moderate increase in long-term exposure to background ambient air pollution was associated with an increased prevalence of respiratory and atopic indicators in children.

Air Pollutants↗

Prevalence of food allergy and its relationship to asthma and allergic rhinitis in schoolchildren.

BACKGROUND: Food allergy (FA) is an important health problem. However, epidemiological studies at the population level are scarce. We assessed the prevalence of FA and its associations with respiratory manifestations among schoolchildren. METHODS: A total of 6672 schoolchildren aged 9-11 years recruited from 108 randomly chosen schools in six French cities underwent a clinical examination including skin prick test (SPT) to common food and aeroallergens and the standardized protocol of the run test to assess exercise-induced bronchial hyper-responsiveness (EIB). Asthma, allergic rhinitis (AR) and clinical symptoms of FA were determined using a standardized questionnaire completed by parents. RESULTS: About 2.1% of the children reported symptoms of FA, 1.9% were sensitized to food allergens, and 0.1% had SP-tested FA. The AR was more prevalent than asthma (20.0% lifetime, 11.9% past year vs 9.8%, 8.7% respectively). Reported FA, food sensitization and SP-tested FA were all positively associated with asthma and AR (P < 0.001). These associations persisted also for FA not manifesting as respiratory symptoms (P < 0.001). Asthma and AR remained significantly associated with reported symptoms of FA and allergic sensitization to food allergens after adjustment for confounders as well as for sensitization to aeroallergens. No relationship existed between EIB (9.0%) and FA. CONCLUSION: The relationships between FA and asthma and AR could be totally explained neither by the existence of respiratory manifestations of FA nor by sensitization to aeroallergens. The FA might intervene differently in asthma and AR.

Asthma↗

Interrelationships among asthma, atopy, rhinitis and exhaled nitric oxide in a population-based sample of children.

BACKGROUND: Exhaled nitric oxide (eNO) has attracted increasing interest as a non-invasive marker of airway inflammation in asthma. However, little evidence exists on the influences exerted on eNO by the interrelations among atopic status, asthma and rhinitis. METHODS: Among the 1156 children who participated in a large-scale epidemiological survey on asthma and allergies (ISAAC II: International Study of Asthma and Allergies in Childhood Phase II) in the city of Clermont-Ferrand, 53 asthmatics without corticosteroid treatment and 96 non-asthmatics were invited to perform eNO and skin prick tests (SPTs) to 12 common allergens. RESULTS: Atopic asthmatic children had higher eNO than non-atopic asthmatic children (28.9+/-9.1 vs. 17.1+/-13.1 p.p.b.; P=0.0004) with a significant increase when one SPT or more are positive (26.5+/-7.8 vs. 17.1+/-13.1 p.p.b.; P=0.03). Similarly, non-asthmatic, atopic subjects had higher eNO than non-atopic subjects with a significant increase when two SPTs or more are positive (19.4+/-9.8 vs. 11.7 +/-6.7 p.p.b.; P=0.003). In the case of equal levels of positive SPTs (0, 1, >/=2), asthmatic children always had higher eNO than non-asthmatic ones. Furthermore, among non-asthmatic children, the eNO level increased only in atopics who had rhinitis (20.7+/-13 vs. 12.5+/-6.4 p.p.b. in atopic controls (subjects without rhinitis and asthma) and 12.3+/-6.6 p.p.b. in non-atopic controls; P=0.001), whereas among asthmatic children, eNO level increased in atopics independently of rhinitis (28.2+/-9.5 p.p.b. in those with rhinitis and 30.9+/-8.1 p.p.b. in those without) as well as in non-atopics with rhinitis (22.5+/-17.2 p.p.b.). CONCLUSIONS: Our data suggest that besides atopy and asthma, allergic rhinitis should also be taken into account in the assessment of eNO.

Analysis of Variance↗

[Pulmonary nodules: dosimetric and clinical studies at low dose multidetector CT].

PURPOSE: To measure breast radiation dose from multidetector CT using three different low dose protocols and compare it to a standard two view chest examination. To compare the number of pulmonary nodules detected at low and standard dose. MATERIALS AND METHODS: Thermoluminescent dosimetry was used to measure the absorbed dose on a phantom (Rando) and 10 patients. Then, we compared the standard dose to the low dose examinations. The Wilcoxon rank test and the kappa test were used to assess differences in the detection of nodules. RESULTS: The absorbed dose of these low dose protocols correspond to the radiation dose for the acquisition of two to ten chest radiographs (two views). This study suggests that only the 30 mA protocol is sufficient for the detection of all pulmonary nodules; nodules smaller than 5 mm were overlooked at 10 mA. CONCLUSION: A good image quality can be obtained with low dose protocols at multidetector CT (correspond to 2 to 10 chest radiographs).

Aged↗

[Analysis of nasal and exhaled nitric oxide concentration in nasal polyposis].

UNLABELLED: Nitric oxide (NO) is implicated in the pathophysiology of inflammatory airway diseases. It has been identified as a potential marker of airway inflammation. OBJECTIVE: The purpose of the study was to assess the concentrations of nasal NO in upper and lower airways in nasal polyposis patients. PATIENTS: 18 nasal polyposis patients (14 men, 4 women) and 21 control subjects (7 men, 14 women), all non asthmatic non smokers, without respiratory infections were prospectively studied. METHODS: They included nasal obstruction scoring, nasal endoscopic grading, allergy testing, nasal cytology, flow-volume spirometry and measurement of nasal (NNO) and exhaled NO (ENO) concentrations. NO was measured by a chemiluminescence NO Analyser (Sievers 280). NNO was analysed by aspiration with a constant flow of 3 l/mn. ENO was analysed during a slow expiration (50 ml/s) against a constant resistance of 10 cm H2O. RESULTS: NNO was significantly (p<0,001) decreased in NP group (596.4 +/- 102.06 ppb) compared to control group (2 251.6 +/- 288.6 ppb). ENO was significantly (p<0.05) increased in NP group (45.4 +/- 14.1 ppb) compared to control group (11.2 +/- 1.16 ppb). NNO and ENO were not significantly different between atopic and non-atopic NP patients. NNO concentrations was inversely correlated with the values of nasal endoscopic grading. No correlation was found between NNO concentrations and respectively nasal obstruction scoring and eosinophil count in nasal mucosa. CONCLUSION: Further studies are necessary to understand the pathophysiology of decreasing NNO and increasing ENO in nasal polyposis. In particular, ENO could be consider as a biologic marker of lower airway inflammation in nasal polyposis.

Adult↗

Basal production of pentane in expired gas from healthy humans.

BACKGROUND: Pentane in exhaled gas is often used as an index of lipoperoxidation, but today, there is no standardization for its measurement. In this study, with our technical experience, we determined basal production of pentane in healthy subjects, and we evaluated variability of pentane flow 1 month later. METHODS: 18 subjects inhaled hydrocarbon-free air (HCFA) in order to realize a lung washout. Ambient air and three samples (at T0, T10, T30 min) of expired gas were concentrated using a "trap-and-purge" procedure. For the analysis of pentane, an Al(2)O(3)/KCl plot column contained in a gas chromatograph equipped with a flame ionization detector was used. RESULTS: After 10 min of washout, mean (+/-SD) exhalation rate of pentane was 1+/-0.6 pmol min(-1) kg(-1). After 30 min of washout, mean (+/-SD) exhalation rate of pentane was 0.7+/-0.5 pmol min(-1) kg(-1). No significant difference in pentane flow was shown 1 month later for eight subjects who repeated the protocol. CONCLUSION: With our results and data of the literature, exhalation rates of pentane from healthy adults appear to range between 0.3 and 2 pmol min(-1) kg(-1). The variability of pentane flow 1 month later seems not very important.

Adult↗

[Atherosclerosis--the role of nitric oxide].

ATHEROSCLEROSIS: Currently regarded as a multifactorial disease, atherosclerosis involves several factor including: oxidized LDL, endothelial cells, macrophages, immune cells, vascular smooth muscle cells. The endothelium appears to play a key role through the production of vasomotor, antiaggregate and leukocyte antiadhesion molecules. NITRIC OXIDE: NO is one of the most important mediators of endothelial antiatherothrombotic functions. Loss of endothelial production, called "endothelial dysfunction", i.e. loss of endothelial vasorelaxing, antiaggregate and leukocyte antiadhesion properties, could lead to increased fatty streak formation and acute arterial events (thrombus formation, vascular spasm). ANIMAL EXPERIMENTS: Although animal models strongly suggest a major role for NO in the pathophysiology of atherosclerosis, human studies with nitrates have been disappointing to date. The local effect of NO is probably closely adapted to local conditions. Therefore, massive delivery of NO as is achieved with nitrates could not repair endothelial dysfunction.

Animals↗

Clinical characteristics and outcome of patients with invasive pneumococcal disease, Puy-de-Dôme, France, 1994-1998.

A surveillance program for invasive pneumococcal disease was undertaken in Puyde-Dĵme, an administrative district of the region Auvergne in France, from 1 January 1994 to 31 December 1998. A total of 214 cases were identified. The annual incidence of invasive pneumococcal disease increased (P=0.04) from 5.5 in 1994 to 9.3 cases per 10(5) person-years in 1998. The highest incidences were for children <2 years of age (59.2 cases per 10(5) person-years) and for adults > or = 65 years (18 cases per 10(5) person-years). Clinical diagnoses, available in 200 patients, included acute pneumonia (62%), meningitis (10%), sepsis without focus (20%), and others (8%). The most frequent chronic medical conditions of the patients included smoking, alcoholism, cardiovascular and pulmonary diseases, and malignancies. Thirty-one percent of the isolates were nonsusceptible to penicillin. Penicillin resistance (MIC > or = 0.1 mg/l) was more frequent (P=0.02) in cancer patients. The overall case-fatality rate was 21.5%. Risk factors for death were age, sex, and underlying diseases of the patients, along with the severity of illness. These population-based findings should convince clinicians to offer pneumococcal vaccine to patients at high risk for invasive pneumococcal disease, thereby increasing vaccination coverage levels in France.

Adolescent↗

Alteration of plasmalemmal caveolae mimics endothelial dysfunction observed in atheromatous rabbit aorta.

OBJECTIVE: In endothelial cells, nitric oxide (NO) is produced by the endothelial isoform of nitric oxide synthase (eNOS), which is localized in the cholesterol-rich plasmalemmal microdomains involved in signal transduction, known as caveolae. The present study was undertaken to evaluate the effect of hypercholesterolemia and fatty streak formation on the endothelial caveolae and on endothelial function, and attempted to determine to what extent the caveolae were involved in endothelium-derived NO production. METHODS AND RESULTS: We first studied the effect of atheroma on endothelial NO production. Fatty streak infiltrated aorta of cholesterol-fed New Zealand White rabbits demonstrated an impairment of acetylcholine-induced relaxation and nearly normal calcium ionophore A23187-induced maximal relaxation. The abundance of caveolae in the endothelium covering the fatty streak, as well as their 'grape-like' clustering, appeared to be decreased. We therefore investigated the effect, on endothelial NO production, of the cholesterol-binding agents 2-hydroxypropyl-beta-cyclodextrin (hp-beta-CD) and filipin, known to alter caveolae structure and/or function. Treatment with either hp-beta-CD (2%) or filipin (4 microg/ml) did not affect contraction to phenylephrine or relaxant responses to A23187 or to the NO donor sodium nitroprusside. In contrast, both treatments impaired acetylcholine-induced relaxation. Cultured bovine aortic endothelial cells (BAEC) similarly treated with hp-beta-CD demonstrated a 50% decrease of total cellular cholesterol and a decreased abundance of caveolae as well as their 'grape-like' clustering. Cholesterol depletion decreased the bradykinin-induced transient peak of free intracellular calcium and subsequent receptor-stimulated NO production (assessed using reporter cells rich in soluble guanylyl cyclase), whereas that elicited by A23187 remained unaltered. CONCLUSION: Fatty streak deposit is associated with a decrease in caveolae 'transductosomes' abundance which appears to represent a novel mechanism of endothelial dysfunction.

2-Hydroxypropyl-beta-cyclodextrin↗

Oxygen toxicity: simultaneous measure of pentane and malondialdehyde in humans exposed to hyperoxia.

In order to estimate cell damage caused by free radicals during oxygenotherapy, we investigated the time course of two markers of lipoperoxidation: pentane in breath and malondialdehyde (MDA) in blood during brief normobaric hyperoxia. Nine healthy subjects inhaled hydrocarbon-free air (HCFA) for 30 minutes, hydrocarbon-free 100% O2 (HCFO2) for 125 minutes and then HCFA for 70 minutes. After 15 minutes of washout with HCFA, ambient pentane was eliminated. After HCFO2, at T175 versus T30 (i.e., 145 min from the start of 100% HCFO2), pentane production increased (P< 0.05). MDA rose significantly at T155 min (i.e., 125 min from the start of HCFO2), versus T30 (P< 0.01). These results suggest that acute hyperoxia causes a moderate increase in lipid peroxidation in healthy subjects. The increase of pentane and MDA confirms that acute hyperoxia induces lipid peroxidation in healthy subjects.

Aged↗

[Acquired angioneurotic edema. Clinical and biological characteristics in 9 patients].

OBJECTIVE: Angioneurotic edema (AE) is a rare but severe disease. Hereditary AE is the more well-known form. The acquired form is exceptional: the symptoms are the same but there are some biologic and treatment differences. We investigated the clinical and biochemical features in nine patients with acquired angioneurotic edema (AAE). PATIENTS AND METHODS: Four of the patients with type I AAE presented an accelerated metabolism of C1Inh, associated with a hematology disease. Their C4, C1q and C1Inh plasma levels were low. Four patients had type II AAE associated with an autoantibody to C1Inh. Their C1Inh plasma levels were normal or low but the functional levels were low in all four. One patient had AAE induced by oral contraceptives. The C1Inh plasma level was normal but the functional level was very low; there were no autoantibodies. Symptoms resolved when oral contraceptives were withdrawn and the C1Inh level returned to normal. DISCUSSION: Treatment of AAE is a difficult matter. For type I AAE, it consists in treating the associated disease. For type II AAE, the treatment goal is to lower the autoantibody level. Management of these diseases requires close collaboration between clinicians and biologists.

Adult↗

[Nasal soluble levels of ICAM-1 in allergic rhinitis].

UNLABELLED: Adhesion molecules, such as intercellular adhesion molecule-1 (ICAM-1), play an important role in the development of the inflammatory allergic response in the nose. ICAM-1 expression on nasal epithelial cells during allergic reaction is regarded as a major hallmark of allergic inflammation. OBJECTIVE: The aim of the study was to evaluate the levels of soluble ICAM-1 (sICAM-1) in nasal epithelial lining fluid (ELF) in patients with allergic rhinitis. PATIENTS: Seventeen patients with perennial allergic rhinitis (age: 34,6 +/- 14,6) were screened and the results were compared with those from 11 seasonal allergic rhinitis patients (age: 25.9 +/- 7.4) and 10 non-allergic patients. METHODS: The study was performed outside the pollen season. The scores of subjective symptoms were estimated by two differents methods. First, on the basis of a visual analog scale for the symptoms including nasal obstruction, rhinorrhea, sneezing and pruritus. This score was called "Autoscore" (fullmark =40 points). Second, on the basis of a four mark scale for each symptom defined (0 =no symptom, 1 =mild, 2 =moderate, 3 =severe). This score was called "Heteroscore" (fullmark =12 points). Specimens of nasal mucosa were collected by brushing the surface of nasal cavity. Levels of sICAM-1 and sECP (soluble Eosinophilic cationic protein) were measured by specific enzyme-linked immunosorbent assay. RESULTS: The levels of sICAM-1 in ELF were significantly higher (p <0.01) in patients with perennial rhinitis compared to patients with seasonal rhinitis outside the pollen season and to non allergic patients. Levels of sICAM-1 in patients with perennial allergic rhinitis were correlated with levels of sECP (p <0.003) and with the four mark scale scores (p <0. 03) but did not correlate with the visual analog scale scores. CONCLUSIONS: sICAM-1 increased in nasal secretions during natural perennial rhinitis and could be considered as a representative hallmark for clinical severity and follow-up evaluation in perennial allergic rhinitis.

Adult↗

[Clinical and biological investigation of NO].

Furchgott et al. demonstrated in 1980 that relaxation of arterial smooth muscle cells in response to acetylcholine is dependent on the integrity of endothelium. They named the factor responsible of this intercellular relationship EDRF (Endothelium Derived Relaxing Factor), which was identified 7 years latter as nitric oxide (NO), a free radical gas. In vessels, NO is generated locally by the endothelial NO synthase and its effect is mainly paracrine (relaxation of the underlying smooth muscle cells, and inhibition of platelet aggregation). The in vivo half-life of NO is short, and the assessment of its production is thus difficult. Invasive and non invasive techniques are now available to explore the variations of arterial diameter or flow. Furchgott's pioneering work anticipated the whole pathophysiology of endothelial-dependent relaxation. Indeed, numerous diseases, in particular atherosclerosis, are accompanied by abnormalities of endothelial-dependent vasodilation ("endothelial dysfunction"). Whereas acetylcholine (or serotonin) infused in a normal artery elicits a vasodilation, in contrast, it promotes a vasoconstriction in an atheromatous artery, as a consequence of a decrease in NO bioavailability. This defect in NO favors arterial spasm, interaction between platelets and arterial wall and thrombosis, and thus probably cardiovascular events. NO cannot be measured directly in humans, except in exhaled NO. In vivo, NO is rapidly oxidized in nitrite (NO2-) and in nitrate (NO3-), the summation being NOx. We shall detail the limitations of this measurement as a biochemical index of NO production from "endothelial" origin.

Animals↗

Increased resting energy expenditure is related to plasma TNF-alpha concentration in stable COPD patients.

UNLABELLED: The objective of this study was to test whether increased resting energy expenditure (REE) in chronic obstructive pulmonary disease (COPD) patients is related to increased cost of breathing and/or to increased cytokine production. In 36 non-inflammatory (CRP: 17.6 +/- 13.1 mg.l(-1), mean +/- SD; orosomucoid: 0.71 +/- 0.18 g.l(-1)), non-malnourished (BMI: 23.6 +/- 4.3 kg.m(-2)), clinically stable, non severely hypoxic COPD patients (60.5 +/- 8.9 years) we measured REE, pulmonary function and plasma cytokine concentrations (TNF-alpha, IL1 and IL6). REE was increased by 10 +/- 11% (P< 0.001) above predicted values. Plasma TNF-alpha concentration was increased in all patients (mean value 26.3 +/- 14.3 pg.ml(-1)). Excess REE (with respect to values predicted by Harris-Benedict equations) was correlated with plasma TNF-alpha concentration (P< 0.005), but not with the degree of airway obstruction, lung overinflation, or with oxygen cost of breathing. Theophylline treatment resulted in a significant increase in REE by 15%. IN CONCLUSION: non-malnourished, clinically stable, non-severely hypoxic COPD patients display an increased REE that is related with plasma TNF-alpha concentration (without apparent systemic inflammation) and to theophylline treatment, but that is independent of parameters of respiratory function.

Basal Metabolism↗