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Biomedical subjects

A Cartier

Publications and source records attributed to A Cartier.

At least 55 records · Page 3Linked to original sources
PubMed1997

Prevalence and intensity of rhinoconjunctivitis in subjects with occupational asthma.

Subjects with occupational asthma may also report symptoms of rhinoconjunctivitis. The aims of this study were: 1) to assess the prevalence of rhinoconjunctivitis in association with occupational asthma, and the severity of rhinoconjunctivitis according to the type of agent (high (HMW) and low (LMW) molecular weight agents) causing occupational asthma; and 2) to evaluate the timing of occurrence of symptoms of rhinoconjunctivitis in relation to those of occupational asthma. A questionnaire on symptoms of rhinoconjunctivitis and its timing in relation to the development of chest symptoms was prospectively addressed to 143 subjects consecutively referred to an occupational asthma clinic. Objective testing through specific inhalation challenges confirmed the diagnosis of occupational asthma in 40 subjects. Symptoms of rhinitis were reported at some time by 37 of the 40 subjects (92%), and of conjunctivitis by 29 of the 40 subjects (72%). The prevalence of symptoms was not different for HMW and LMW agents, although rhinitis was more intense for HMW (19 out of 24 subjects with three or more of the following symptoms: runny nose, itchy nose, nasal blockage, and sneezing) than for LMW (5 out of 14 subjects) (p<0.01). There were significantly fewer subjects with occupational asthma due to LMW agents, with rhinitis appearing before asthma (p=0.03). Figures for conjunctivitis showed a similar trend, but did not reach statistical significance. In conclusion, symptoms of rhinoconjunctivitis are often associated with occupational asthma. Rhinitis is less pronounced in the case of low molecular weight agents, but more often appears before occupational asthma in the case of high molecular weight agents.

Adult↗
PubMed1997

Bronchial subepithelial fibrosis correlates with airway responsiveness to methacholine.

OBJECTIVES: To evaluate the relationships between airway subepithelial collagen deposition and epithelial desquamation with airflow obstruction and hyperresponsiveness in different types of asthma and other respiratory conditions such as chronic cough and allergic rhinitis. DESIGN AND PARTICIPANTS: We compared the histopathologic features observed on bronchial biopsy specimens obtained from 80 subjects: 38 with different types of asthma, 19 with chronic cough, 13 with allergic rhinitis, and 10 normal control subjects. Each subject had a questionnaire on respiratory symptoms and medication needs, measurements of expiratory flows and methacholine responsiveness, allergy skin prick tests, and a bronchoscopy with bronchial biopsies. None of the subjects studied used bronchial anti-inflammatory agents. RESULTS: Different degrees of bronchial subepithelial fibrosis were present in asthmatic subjects, the most intense being observed in occupational asthma; a subepithelial deposition of collagen was also found in subjects with allergic rhinitis, although it was less intense than in asthma and irregularly distributed under the basement membrane. On global analysis, we found a significant correlation between individual provocative concentration of methacholine inducing a 20% fall in FEV1 (PC20) and subepithelial fibrosis intensity (rs=-0.70, p<0.001). The degree of epithelial desquamation was correlated with that of subepithelial fibrosis (rs=0.36, p=0.02) in subjects with normal airway responsiveness, but it was not correlated with the PC20 (rs=0.10, p>0.05). Neither the degree of subepithelial fibrosis nor epithelial desquamation was correlated with the FEV1. CONCLUSION: These results suggest that structural airway changes such as subepithelial collagen deposition may be significant determinants or markers of a process that results in airway hyperresponsiveness.

Adult↗
PubMed1996

Occupational asthma caused by aromatic herbs.

We describe a subject with occupational asthma caused by several aromatic herbs: thyme, rosemary, bay leaf, and garlic. The diagnosis was confirmed by several inhalation challenges in the laboratory. Although immediate skin reactivity was demonstrated to the herbs the subject reacted to by inhalation, RAST showed that garlic was the most potent allergen by weight, the other herbs showing less reactivity. These aromatic herbs, bay leaf, thyme, and rosemary, should be included among agents causing occupational asthma in the food industry.

Adult↗
PubMed1996

Influence of inhaled steroids on recovery from occupational asthma after cessation of exposure: an 18-month double-blind crossover study.

Occupational asthma (OA) is a useful model for the study of asthma in humans. The possibility that inhaled corticosteroids, in addition to withdrawal from the workplace, could improve clinical and functional recovery from OA can be hypothesized. We assessed clinical, functional, and behavioral characteristics of 32 subjects (22 male, 10 female), in all but one of whom OA was confirmed by specific inhalation challenges induced by either high- (n=13) or low-molecular-weight (n=19) agents within 3 mo after cessation of exposure. In this randomized, crossover, double-blind study, subjects (paired for baseline PC20 and duration of symptoms after exposure) received either placebo or 1,000 micrograms of inhaled beclomethasone daily for 1 yr, followed by the alternate medication for 6 mo. Various clinical, functional, and behavioral parameters were examined at each 3-mo visit. Significant improvement in clinical (nocturnal symptoms, cough), functional (morning and evening peak expiratory flow rates), and behavioral (quality of life) parameters were detected in the active-treatment period, although the magnitude of the improvement was relatively small. Side effects (oropharyngeal, reduced cortisol) were similar in the placebo and treatment groups. Distinguishing subjects who started with the active preparation from those who were given placebo first showed that most clinical and behavioral parameters improved in the former instance, whereas there was no significant difference in the latter. We conclude that inhaled corticosteroids induce a small but significant overall improvement of the asthmatic condition in subjects with occupational asthma caused by high- and low-molecular-weight agents after withdrawal from exposure. The beneficial effect is, however, more pronounced if inhaled steroids are given early after diagnosis.

Administration, Inhalation↗
PubMed1996

Outcome of specific bronchial responsiveness to occupational agents after removal from exposure.

A decrease in specific bronchial responsiveness (SBR) could occur after removal from exposure to an agent causing occupational asthma as a result of loss of immunologic and/or nonspecific bronchial reactivity (NSBR). We studied 15 subjects with occupational asthma (eight to a high- and seven to a low-molecular-weight agent, isocyanate in all instances), proved by specific inhalation challenges (SIC) done 2 yr or more before. Subjects were reexposed in the same way as in the initial SIC: for subjects who did not react, the exposure was increased until either an asthmatic reaction occurred or a maximum of 2 h was reached. NSBR was assessed before and after SIC. Subjects had a decrease in their SBR if the total dose of agent necessary to induce asthmatic reaction was greater by twofold compared with the initial SIC. There was a significant improvement in NSBR in seven of 15 subjects. Nine of 15 subjects (60%) had a decrease in their SBR. Only one had a complete loss of SBR. Changes in NSBR, molecular weight of the offending agent, decrease of antibody level against offending agents, or duration of exposure at work did not explain the decrease in SBR. We conclude that after removal from exposure to the offending agent a majority of subjects (60%) show a decrease but a persistence of SBR to high- and low-molecular-weight agents.

Asthma↗
PubMed1996

Fever and leucocytosis accompanying asthmatic reactions due to occupational agents: frequency and associated factors.

Fever is sometimes associated with asthmatic reactions following specific inhalation challenges with occupational agents. Our aims were to estimate the prevalence of fever in subjects with occupational asthma confirmed by specific inhalation challenge and to examine the characteristics and clinical correlates of subjects who develop fever on specific inhalation challenge. We performed a retrospective analysis of 317 subjects who had positive specific inhalation challenge to occupational agents and a comparison of subjects who developed fever after specific inhalation challenge with a random sample of those who did not. Fifteen subjects (5%) developed fever associated with positive specific inhalation challenge. They were compared with a random sample of 60 subjects who did not develop fever. The fever group: 1) showed a larger increase in absolute number of blood neutrophils, and a larger decrease both of blood lymphocytes and forced vital capacity after specific inhalation challenge; 2) included fewer atopics; 3) had been exposed more frequently to low rather than high molecular compounds; and 4) always experienced a late reaction and had more atypical reactions. We conclude that after positive specific inhalation challenge; fever occurs infrequently, and is associated with an increase in blood neutrophils and a decrease in blood lymphocytes and forced vital capacity. Such reactions seem more likely to occur in nonatopic subjects exposed to low molecular weight agents.

Adult↗
PubMed1996

Compliance with and accuracy of daily self-assessment of peak expiratory flows (PEF) in asthmatic subjects over a three month period.

Serial peak expiratory flow (PEF) assessment has been proposed in the clinical evaluation of asthma. In subjects attending the asthma clinic of a tertiary care hospital, we wanted to assess: 1) compliance in performing PEF; and 2) accuracy of a PEF-diary. Twenty adult asthmatic subjects, all using inhaled steroids, were asked to assess their PEF in the morning and evening with a VMX instrument (Clement Clarke Int., Colombus, OH, USA). This instrument, which incorporates a standard mini-Wright peak flow meter, stores PEF data on a computer chip. Subjects were not informed that the values were being stored. The mean duration of PEF monitoring was 89 days (range 44-131 days). For the total of 20 subjects, it was estimated that 3,482 values should have been written down and stored on the VMX computer chip. Whilst 1,897 values (54%) were written down, only 1,533 (44%) were stored, 425 values being invented. Morning and evening values were stored on 34% of days; and values were stored at least once a day on 55% of days. The values written down corresponded precisely to stored values 90% of the time, and were within +/- 20 L 94% of the time. We conclude that: 1) compliance with daily peak expiratory flow assessments is generally poor in chronic stable asthmatic subjects assessed on two visits separated by a 3 month period; and 2) a substantial percentage of values (22%) is invented. The unsatisfactory compliance with peak expiratory flow monitoring in this group of asthmatics on inhaled steroids underlines the need for similar studies on peak expiratory flow monitoring as part of an action treatment plan, and in more severe and brittle asthmatics.

Administration, Inhalation↗
PubMed1996

Closed-circuit apparatus for specific inhalation challenges with an occupational agent, formaldehyde, in vapor form.

Specific inhalation challenges are an important tool for confirming occupational asthma. In recent years, we have described two closed-circuit apparatuses that allow exposure to stable and controlled concentrations of particles and isocyanate gases. More recently, we developed a similar apparatus that generates chemicals in vapor form. The aim of this work is to describe its performance in the specific case of formaldehyde. This instrument is made of four parts: a generator as such, an exposure chamber, a monitor, and an automated regulatory system. This apparatus was assessed in four subjects suspected of having formaldehyde-induced asthma or alveolitis. The concentrations of formaldehyde were increased from 0.5 to 1 mg/m3 to 3 mg/m3 keeping the concentration at a value of 3 mg/m3 or less (threshold limit value). The dispersion of obtained values by comparison with the median data (6 values) was as follows: maximum value, 12 to 84%; minimum value, 20 to 58%; interquartile range, 0.13 to 0.9 mg/m3. We observed that target concentrations took a few minutes to be reached, but, once they were obtained, delivered concentrations were stable. The new vapor-delivery apparatus allows us to obtain concentrations of formaldehyde that are close to target concentrations with an acceptable dispersion of values around target concentration. Its use should be extended to other chemicals besides formaldehyde.

Administration, Inhalation↗
PubMed1996

Isolated late asthmatic reaction after exposure to a high-molecular-weight occupational agent, subtilisin.

High-molecular-weight agents generally induce immediate asthmatic reactions. We report the case of a subject who experienced a reaction that started after the first hour following exposure to subtilisin, a high-molecular-weight occupational agent. Any occurrence of immediate reaction was ruled out by measuring both FEV1 and lung volumes every 10 min in the first hour. This reaction was IgE-mediated as shown by immediate skin reactivity and increased specific IgE levels.

Adult↗
PubMed1995

Bacterial inoculum density and probability of para-nitrophenol biodegradability test response.

This study has been carried out to establish a model linking probability of positive response in para-nitrophenol biodegradability test to controlled variables of the test (suspended solids, SS; total bacteria, AODC; cultivable bacteria, CFU; specific biodegraders, MPN). Series of dilution of 11 raw inocula (6 activated sludges, 5 river waters) were tested. They reveal very dispersed values of biomass measured as SS, AODC, and CFU and quite comparable values of specific biodegraders for each category of inoculum (river or sludge). The proposed model fits well the empirical distribution of the experimental frequency of positive results versus inoculum density for each controlled variable. The constants k of the model, representing the fraction of biodegraders for each inoculum, were tested by the likelihood ratio test and were proven to be different from one another according to the biomass descriptor and the origin of the inoculum. The probabilistic model, in the case of para-nitrophenol biodegradation, indicates that standardized official tests (closed bottle, AFNOR, Sturm, and MITI I) are seldom optimal under those conditions. It allows the determination of which inoculum concentration can lead to a high probability (e.g., 99.9%) of observing paranitrophenol biodegradation by raw inocula.

Bacteria↗
PubMed1995

Comparison of four-times-a-day and twice-a-day dosing regimens in subjects requiring 1200 micrograms or less of budesonide to control mild to moderate asthma.

The aim of this study was to compare the efficacy, compliance and side-effects of budesonide administered twice daily (b.d.) and four times a day (q.d.) with a Turbuhaler device in asthmatic subjects requiring < or = 1200 micrograms daily. The randomized, parallel group study design included a 2-week baseline period followed by a 6-12-month treatment period. Subjects were assessed at regular intervals in hospital through FEV1, PC20 methacholine, adrenal function and throat swabs. They were asked to record their symptoms and PEF values morning and evening at home. An asthmatic flare-up, which was the main outcome resulting in a patient's termination of the study, was defined beforehand as (a) 25% or greater diurnal variability in PEF for 2 consecutive days, and/or (b) nocturnal awakenings due to asthma symptoms 2 days or more in the same week and/or (c) an increase (doubling or more) in the need for inhaled bronchodilator 2 days in the same week. Fifty-eight adult asthmatic subjects (20 males and 38 females) entered the study, one-half being randomly assigned to the b.d. regimen and one half to the q.d. regimen. Fourteen subjects were on 400 micrograms, 15 subjects on 800 micrograms and 29 subjects on 1200 micrograms of budesonide daily. Seventeen flare-ups were recorded in the b.d. regimen group as opposed to 11 in the q.d. regimen (P = 0.05), significant differences being found in the 800 and 1200 micrograms groups (a total of 13 flare-ups in the b.d. group and eight flare-ups in the q.d. group for the two doses, P = 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Topical↗
PubMed1995

Do subjects investigated for occupational asthma through serial peak expiratory flow measurements falsify their results?

BACKGROUND AND AIM: Serial assessment of peak expiratory flow (PEF) rates has been advocated as a sensitive and specific means of investigating occupational asthma. The possibility that, for several reasons, subjects do not accurately report their values has been raised. The availability of portable instruments that assess PEF and store timings and values now make it possible to estimate compliance and accuracy of results. METHODS: Twenty-one subjects consecutively investigated for occupational asthma were asked to assess their PEF every 2 hours during the day, both at work and away from work, with a VMX instrument (Clement Clarke International, Columbus, Ohio) and record the times and values on a sheet of paper. The subjects were not aware that the data were also being stored on a computer chip. The diagnosis was occupational asthma in eight subjects, personal asthma in four subjects, and neither condition in nine subjects. RESULTS: The mean duration of recording was 36 days (range, 14 to 79 days). At least 6048 values should have been recorded, but only 4839 (80%) were either recorded or stored. Reported values corresponded precisely to stored values in 2533 of 4839 recordings (52%). The timing of the recording was also examined in relation to the time at which the recording was solicited; values recorded within 1 hour of the solicited time were judged as acceptable. Of the total of 3342 recordings stored, 2375 (71%) satisfied this criterion. Compliance was significantly less satisfactory in those referred by the Workers' Compensation Board (n = 11). CONCLUSION: In this survey of 21 subjects investigated for possible occupational asthma, compliance with PEF recording, as assessed by comparing recorded and stored results and the time at which the recording was solicited, was poor.

Adult↗
PubMed1995

Occupational IgE-mediated sensitization and asthma caused by clam and shrimp.

BACKGROUND: To confirm occupational asthma caused by clam and shrimp in a food company worker, the following investigation was planned in 60 other exposed workers (56 participants). METHODS: Before the production period of clam and shrimp, a medical and occupational questionnaire was carried out and skin and RAST testing were done with common inhalants and clam, shrimp, crab, and lobster extracts. During the production period, environmental monitoring was performed with personal and general samplers; inhalation testing with methacholine was proposed to subjects with immediate skin reactivity to clam, shrimp, or both. After the production period, all subjects with an immediate skin reactivity to clam, shrimp, or both and either a history of rhinoconjunctivitis, asthma, or bronchial hyperresponsiveness were seen by a specialist. RESULTS: Including the index case in whom occupational asthma to clam and shrimp had been confirmed, four (7%) subjects had a history of rhinoconjunctivitis and two (4%) had a history of asthma during the period of clam production, whereas three (5%) subjects had rhinoconjunctivitis and two (4%) had asthma during the shrimp production. Three (5%) subjects had immediate skin reactivity to clam, and nine (16%) subjects to shrimp. Four (7%) subjects had increased specific IgE antibodies (RAST binding > or = 3%) to clam and eight (14%) to shrimp. Significant associations were found between immunologic reactivity to clam and shrimp on the one hand and to crab and lobster on the other. Environmental monitoring demonstrated clam and shrimp on the air sampling filters. Occupational asthma caused by clam was confirmed by specific inhalation challenges in one subject in addition to the index case. These two subjects had skin reactivity and increased specific IgE antibodies to clam, shrimp, or both. CONCLUSION: By including the initial subject, the prevalence of immediate sensitization is 5% to 7% to clam and 14% to 16% to shrimp. Two (4%) subjects had occupational asthma caused by clam, and one (2%) had occupational asthma caused by shrimp.

Adult↗
PubMed1995

Occupational asthma caused by dry metabisulphite.

A case is described of occupational asthma in a worker with no previous history of asthma who sprinkled dried metabisulphite powder onto potatoes and developed work-related symptoms. Occupational asthma was confirmed by specific inhalation challenges.

Adult↗
PubMed1995

The reversibility of airway obstruction to an inhaled beta 2-adrenergic agent is less satisfactory after methacholine testing in asthmatic subjects.

AIMS: The aim of this work was to compare the response to an inhaled beta 2-adrenergic agent in two situations: (1) spontaneous airway obstruction in asthmatic subjects who had withheld treatment with the medication for more than 12 hs; and (2) after methacholine-induced airway obstruction once airway caliber had recovered to the premethacholine test value. SUBJECTS AND METHODS: Sixteen asthmatic subjects who showed a 20% or more improvement in FEV1 after inhaled beta 2-adrenergic agent (B2) (salbutamol, 200 micrograms) entered a double-blind crossover randomized trial in which the following tests were carried out: (1) FEV1 response after inhaling a placebo or active B2; (2) FEV1 response after inhaling a placebo or active B2 after a methacholine test that had induced a 20% or more reduction in FEV1, once FEV1 had recovered to the premethacholine value after inhaling salbutamol in an open fashion. RESULTS: As expected, the mean percent improvement in FEV1 in the spontaneous airway obstruction situation was 21.7 +/- 8.5% after inhaling the active B2 and 2.2 +/- 1.8% after placebo B2 (p < 0.001). Following recovery after methacholine challenge, the FEV1 was slightly superior (mean difference of 146 mL) to the premethacholine value before inhaling the active or placebo B2. In this situation, the percent improvement in FEV1 after inhaling the active B2 was only 7.5 +/- 4.4% and not significantly different from after inhaling placebo B2 (4.9 +/- 5.4%). Consequently, the end FEV1 value after inhaling active B2 was significantly higher in a situation of spontaneous airway obstruction than after methacholine-induced airway obstruction (mean difference = 110 mL; p = 0.02). CONCLUSION: After a methacholine test, the reversibility of an inhaled beta 2 agent is not significantly different from a placebo and is less satisfactory than in a situation of spontaneous airway obstruction. The mechanism for this needs to be explored but it is not secondary to persisting airway obstruction.

Adult↗
PubMed1995

Occupational asthma caused by oak wood dust.

Three cases of occupational asthma caused by oak wood dust are presented. The diagnosis was confirmed by specific inhalation challenges, which induced a dual asthmatic reaction in two subjects and an atypical prolonged immediate reaction in one subject.

Adult↗
PubMed1995

[Chronic hyperventilation syndrome. The role of respiratory re-training].

This study compares three non-pharmacological approaches to the chronic hyperventilation syndrome (CHS). Eighteen subjects were evaluated at the start of the study then one and 6 months after having received in a random fashion one of the following treatments: group I (teaching approach of one hour on the respiratory physiology of the CHS and on breathing techniques; n = 5); group II (same approach as in group I with breathing retraining of 8 sessions; n = 8); group III (same as group II with the addition of a modified Jacobson's progressive relaxation; n = 5). Whereas all three groups had a similar symptomatic score at the beginning of the study (although subjects of group III had in general higher scores and were symptomatic for a longer period), our results show that all subjects improved after 4 weeks, those in group II showing the greatest improvement (p < 0.05). This confirms the relevance of applied and repeated pedagogy in approaching subjects with the CHS.

Adolescent↗