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Biomedical subjects

L Perfetti

Publications and source records attributed to L Perfetti.

At least 37 records · Page 2Linked to original sources
PubMed1999

Cell ashing for trace element analysis: A new approach based on ultraviolet/ozone.

We studied a new approach to cell ashing based on illuminating the specimens with a low-pressure mercury discharge lamp. We analyzed with synchrotron spectromicroscopy its effects on different physiological elements in neurobiological specimens. Our results demonstrate that carbon is removed, whereas phosphorus, calcium, potassium, and sulfur are retained and their relative concentrations are enhanced. Applied to trace elements, this technique will enhance their practical detectability.

Animals↗
PubMed1999

Serum eosinophil cationic protein (sECP) in subjects with a history of asthma symptoms with or without rhinitis.

BACKGROUND: Serum eosinophil cationic protein (sECP) has been proposed as a marker of disease activity in bronchial asthma. The study aimed to evaluate the role of sECP in screening asthmatics in a group of subjects with asthma and rhinitis symptoms, and the relationship between sECP and clinical and functional parameters of asthma. METHODS: A total of 185 subjects with asthma symptoms, 149 of them with rhinitis as well, underwent skin tests, spirometry, methacholine (MCH) test, blood sampling for eosinophil percentage (bEOS%) and sECP determination, and nasal secretions smear for eosinophil percentage (nEOS%) determination; PEF values, symptoms, and medication over a period of 4 weeks after sampling for sECP quantitation were recorded on a diary. RESULTS: A total of 99 (53%) subjects received a diagnosis of asthma (asthmatics), and 86 did not (nonasthmatics). In asthmatics, neither sECP nor bEOS% was significantly different from nonasthmatics. In asthmatics, sECP was higher in subjects with increased than in those with normal daily PEF variability (16.4, 6.8-24.4 vs 5.3, 3.9-8.4 microg/l; P<0.001). sECP was higher in moderate persistent asthma than in intermittent asthma (24.8, 10.6-53 vs 8.4, 5.6-14.1; P<0.05). In nonasthmatics (73 with a history of rhinitis), both sECP and bEOS% correlated with nEOS% (rho=0.35; P<0.01 and rho=0.53; P<0.001). CONCLUSIONS: In adults with asthma symptoms with or without rhinitis, sECP did not distinguish asthmatics from nonasthmatics. In asthmatics, sECP was associated with PEF variability and symptom severity. In subjects with asthma and rhinitis, as well as in subjects with only rhinitis, sECP levels are possibly influenced by nasal inflammation.

Adolescent↗
PubMed1999

Occupational asthma: a longitudinal study on the clinical and socioeconomic outcome after diagnosis.

AIM: To evaluate the clinical outcome and socioeconomic consequences of occupational asthma (OA). SUBJECTS AND METHODS: Twenty-five patients with OA both to high- and low-molecular-weight agents (3 and 22, respectively) confirmed by specific inhalation challenge were followed up for 12 months after the diagnosis. Upon diagnosis, each patient received a diary on which to report peak expiratory flow rate (PEFR), symptoms, drug consumption, expenses directly or indirectly related to the disease, as well as information regarding personal socioeconomic status. At each follow-up visit (1, 3, 6, and 12 months), the patients underwent clinical examination, spirometry, methacholine (Mch) challenge, and assessment of diary-derived parameters and socioeconomic status. Asthma severity (AS) was classified into four levels, based on symptoms, drug consumption, and PEFR variability. RESULTS: At 12 months, 13 patients (group A) had ceased exposure; the remaining 12 patients (group B) continued to be exposed. At diagnosis, FEV1 percent and provocative dose causing a 20% fall in FEV1 (PD20) of Mch were lower in group A than in group B; patients of group A were also characterized by significantly higher basal AS levels. At 12 months, no significant variation in FEV1 percent or PD20 was found for either group, while AS levels improved in both groups, the change being more marked for group A than group B. Pharmaceutical expense at 12 months significantly (p < 0.05) decreased, as compared with the first month, in group A, whereas it tended to increase in group B. In group A, 9 of 13 subjects had reported a deterioration of their socioeconomic status as compared with 2 of 12 in group B (p < 0.01). A significant loss of income was registered in patients of group A (median 21.45, 25th to 75th percentiles 16.9 to 25.8 Italian liras x 10(6) on the year preceding diagnosis and 15.498, 10.65 to 21.087 Italian liras x 10(6) on the year after diagnosis; p < 0.01), whereas no significant change was seen for patients in group B. CONCLUSIONS: In OA, cessation of exposure to the offending agent results in a decrease in asthma severity and in pharmaceutical expenses, but it is associated with a deterioration of the individual's socioeconomic status (professional downgrading and loss of work-derived income). There appears to be a great need for legislation that facilitates the relocation of these patients.

Adult↗
PubMed1998

Changes in IgE-mediated allergy to ubiquitous inhalants after removal from or diminution of exposure to the agent causing occupational asthma.

BACKGROUND: One possibility, among others, for explaining the persistence of asthma symptoms in occupational asthma (OA) after the cessation of exposure to the causal agents may be that subjects become sensitized to ubiquitous inhalants. OBJECTIVE: The aim of this study was to evaluate the development or increase of IgE-mediated sensitization to ubiquitous allergens, both to high- and low-molecular-weight agents, in 100 subjects with OA after cessation of exposure. METHODS: Subjects were evaluated on a first visit, at the time of diagnosis of OA, coinciding with the cessation or diminution of exposure to the causal agent, and on a second visit, 5.8+/-3.3 years afterwards. At each visit, a history of ocular, nasal and asthmatic symptoms related to exposure to common allergens was obtained together with spirometry and assessment of bronchial responsiveness to methacholine. We analysed total IgE and specific IgE to Dermatophagoides farinae, D. pteronyssinus, birch, ragweed and timothy grass pollens, cat and dog danders, and Alternaria, using enzyme allergosorbent test (EAST) from blood samples taken on each visit. RESULTS: Total IgE levels showed a tendency to diminish. No changes were found in the number of positive EAST (presence of detectable levels of specific IgE) or in the levels of specific IgE. Although significantly more symptoms of rhinoconjunctivitis and asthma in contact with house dust (P < 0.05) and pets (P < 0.01) were reported on the second visit than on the first, no significant changes in the frequency of symptomatic sensitized subjects were found. CONCLUSION: Subjects with OA are unlikely to develop IgE-dependent sensitization to common inhalants after removal from exposure to occupational agents.

Adult↗
PubMed1998

Can reactive airways dysfunction syndrome (RADS) transform into occupational asthma due to "sensitisation" to isocyanates?

The case history is described of a worker who presented with a history suggestive of reactive airways dysfunction syndrome which occurred after an acute high level inhalation of diphenylmethane diisocyanate. Further exposure at work, at a time when concentrations of isocyanates were no longer "irritant", suggested occupational asthma; this diagnosis was confirmed by a specific inhalation challenge test.

Allergens↗
PubMed1998

Comparison of serial monitoring of peak expiratory flow and FEV1 in the diagnosis of occupational asthma.

Peak expiratory flow (PEF) monitoring is often used to establish the relationship between occupational exposure and asthma. FEV1 has been found to be a better physiologic index than PEF in the measurement of airflow obstruction. The aim of this study was to compare the accuracy of serial monitoring of PEF and FEV1 in the diagnosis of occupational asthma. Twenty consecutive subjects referred for possible occupational asthma were asked to perform serial monitoring of PEF and FEV1 using a portable ventilometer. Two sets of graphs were plotted for both PEF and FEV1: graphs with the best of all values and graphs with the best of two reproducible values. Three observers interpreted both PEF and FEV1 recordings by the visual method in a blind, randomized manner as either compatible with occupational asthma or not. Eleven of the subjects had a positive inhalation challenge test (high-molecular-weight agents, n = 6; low-molecular-weight agents, n = 5). In the case of analysis of the graphs plotted with the best of all values, the sensitivity of the PEF recording interpreted by the three observers was 82, 73, and 73%, and of the FEV1 recording as 55, 55, and 45%; specificity of PEF recording was 89, 100, and 100%, and of FEV1 was 56, 89, and 100%. When an agreement between two of the three readers was required to define occupational asthma, sensitivity and specificity were 73 and 100% for PEF and 55 and 89% for FEV1. Lower sensitivities were found when the same analyses were performed with the graphs plotted with the best of two reproducible values. It was concluded that unsupervised FEV1 is not more accurate than unsupervised PEF monitoring in the diagnosis of occupational asthma. Plotting graphs using the best value gives better diagnostic accuracy than plotting them with the best of two reproducible values.

Adult↗
PubMed1998

Follow-up of occupational asthma after removal from or diminution of exposure to the responsible agent: relevance of the length of the interval from cessation of exposure.

STUDY OBJECTIVE: We set the hypothesis that follow-up surveys of occupational asthma (OA) could now show better improvement in the asthmatic condition because of a more prolonged interval since removal from exposure than in previously reported studies. PATIENTS/METHODS: Ninety-nine subjects with OA were assessed and were separated into two groups according to the duration of cessation of exposure: (1) group removed for > or = 5 years: 48 subjects studied 8.9+/-2.2 years after cessation of exposure; (2) group removed for <5 years: 51 subjects with OA, comparable in terms of history and functional results at time of diagnosis, with a time lapse from last exposure of 3.1+/-1.2 years. On the follow-up visit, questionnaires including information on the current and previous use of inhaled steroids, spirometry, and methacholine tests were administered and results were compared with those obtained at the time of diagnosis. RESULTS: At the follow-up visit, no significant changes in spirometry were observed in the two groups. However, a significant improvement in provocative concentration of methacholine causing a 20% fall in FEV1 (PC20) from a mean value of 1.5 to 3.7 mg/mL was documented (p<0.001). The proportion of subjects having normal PC20 at the follow-up visit was significantly higher in the group removed from exposure for >5 years than in the group removed for < or = 5 years (16/33 vs 8/42; p=0.01). Stepwise logistic regression showed that follow-up PC20 could be predicted from baseline PC20 (p<0.001, odds ratio [OR]=4.1, 95% confidence interval [CI]=1.8 to 9.1), duration of exposure (p=0.04, OR=0.9, 95% CI=0.8 to 1.0), the interval since removal from exposure (p=0.002, OR=1.7, 95% CI=1.2 to 2.5), and the type of agent; subjects with OA due to high-molecular-weight agent showed a less favorable outcome (p=0.04, OR=0.2, 95% CI=0.03 to 1.0). Current and past treatments with inhaled steroids were not significant predictors. CONCLUSION: Results obtained in the group of this study removed for >5 years show better prognostic figures than those reported in most previous studies. Comparison with the group removed for a shorter interval and the stepwise logistic regression analysis suggest that the longer duration of the interval from cessation of exposure appears to be a factor determining this difference.

Adult↗
PubMed1997

Clinical evaluation of occupational asthma.

In this paper, the procedures in the assessment of occupational asthma (OA) are discussed. Only the most common subtype of OA is considered here, i.e. that in which symptoms appear after a latency period from the beginning of exposure. OA is characterized by variable bronchial obstruction, and variable bronchial hyperresponsiveness caused by specific agents inhaled at work. The clinical investigation of OA is a stepwise approach which includes a comprehensive history together with physiological and immunological studies. The first step is to identify symptoms and relate exposure at work to the presence in the workplace of substances known to provoke OA. The presence of bronchial asthma must then be confirmed; this is achieved by assessing the reversibility of bronchial obstruction and/or the presence of nonspecific bronchial hyperreactivity and/or the presence of significant peak expiratory flow (PEF) variability. The relationship between work and symptoms may first be assessed by means of serial measurements of PEF and of nonspecific bronchial hyperreactivity during periods at work and away from work. When the suspected agent is a high-molecular-weight (HMW) or a low-molecular-weight (LMW) agent known to act through an immunoglobulin E (IgE)-mediated mechanism, skin tests and/or research for specific IgE should be performed. In case of sensitization, where a relationship between asthma and work has been demonstrated by means of serial monitoring of PEF, a diagnosis can be made. If the suspected agent is a LMW agent, a specific inhalation challenge test in the laboratory or at the workplace is necessary.

Asthma↗
PubMed1995

Patients' interest in educational programmes on asthma.

The compliance of patients in educational programmes on asthma is sometimes lacking and this may be due in part to patients' scarce interest or refusal to expand their knowledge of the disease. In the present study, we aimed to evaluate the interest of a group of asthmatic patients in education on asthma and to point out the asthma-related topics considered particularly worth discussing. The study was conducted before starting the educational programme. Sixty adult patients with mild-to-moderate asthma were asked to complete a questionnaire, including a group of 14 questions aimed at evaluating the level of patients' interest in various asthma-related topics, one question regarding patients' willingness to attend a small-group educational course on asthma, and a further question asking patients to suggest topics of particular interest for discussion. For each of the first 14 questions, patients indicated their level of interest according to a score ranging 1-3. The sum of the scores obtained for each topic (partial score) and the sum of partial scores (total score) were calculated and classified into three classes of interest (I: low, II: medium; III: high), and the distribution of patients into the three classes was analysed (chi-squared test).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Peak expiratory flow monitoring and airway response to specific bronchial provocation tests in asthmatics.

To assess the validity of peak expiratory flow (PEF), measured by means of a peak flow meter, in comparison to forced expiratory volume in one second (FEV1) for measuring the airway response during specific bronchial challenges, we registered PEF and FEV1 in a random sequence during 75 positive (decrease in FEV1 of > or = 15% from baseline) and 75 negative (decrease in FEV1 < 15% from baseline) challenges with chemicals or allergens. The correlation between PEF and FEV1 in terms of absolute values and of percentage of change from baseline was statistically highly significant (p < 0.001) in all challenges and in the different pattern of response, immediate, dual and late. Relative operating characteristic analysis showed that an absolute decrease in PEF of > or = 70 l.min-1 in the immediate and of > or = 80 l.min-1 in the late phase of the response (cut-off points) gave optimal discrimination between challenges with a bronchoconstrictive response (defined as a FEV1 decrease > or = 15% from baseline), and challenges without. These cut-off points, however, were highly specific (92 and 93.3%, respectively), but not as sensitive (70.6 and 61.1%, respectively), and smaller absolute changes in PEF from baseline do not exclude a bronchoconstrictive response. Our data suggest that PEF readings are a useful diagnostic tool in assessing the airway response during a specific bronchial challenge in asthmatics, although with some limitations. PEF readings can be used to monitor the late response to a challenge during the evening and the night if PEF readings are carefully considered in relation to clinical symptoms.

Adolescent↗
PubMed1992

Vitiligo is associated with a significant increase in HLA-A30, Cw6 and DQw3 and a decrease in C4AQ0 in northern Italian patients.

HLA polymorphisms of class I (HLA-A, B, C) of class II (HLA-DR, DQ) and of class III (C4A, C4B, BF) were investigated in 93 Northern Italian patients affected with vitiligo and in 388 controls. Vitiligo patients had significant increases in HLA-A30 (corrected p, pc = 0.0144), Cw6 (pc = 0.0189), DQw3 (pc less than 0.0003) and a significant decrease in C4AQ0 (pc = 0.003). Nonfamilial vitiligo is marked by increases in HLA-A30 and DQw3. Extensive vitiligo is marked by increases in HLA-A30 and Cw6. These findings suggest that immunogenetic mechanisms may be responsible for vitiligo and that unique HLA phenotypes may influence the expression of vitiligo in this population.

Adolescent↗
PubMed1992

Photochemotherapy with topical khellin and sunlight in vitiligo.

In order to evaluate the efficacy of topical khellin the vitiligo macules of one side only were painted in 41 patients with a 2% solution of khellin in acetone and propylene glycol (90 and 10%, respectively) and exposed to sunlight for a period of 4 months with 3 weekly applications and with exposure times up to 90 min. The macules of the other side were treated in 36 of the 41 patients with acetone and propylene glycol only and sun-exposed with the same schedule, while in the remaining 5 patients they were neither treated with khellin or placebo nor sun-exposed. No significant difference was evidenced between the khellin and placebo-treated sides: no excellent result (repigmentation more than 75% of the affected area) was found, and good results (repigmentation more than 50%) were found in 24.9% of khellin- plus sunlight-treated macules and in 22.3% of placebo- plus sunlight-treated macules.

Administration, Topical↗
PubMed1992

Polymorphisms of HLA class III genes in allergic contact dermatitis.

HLA class III polymorphisms (BF, C4A, C4B) were studied in 55 patients of different age and sex suffering from allergic contact dermatitis, with sensitization to different substances. In the overall group of patients no significant correlation between the disease and HLA markers was found. BF F allele was present in 34% and BS S in 64% of patients suffering from allergic contact dermatitis to nickel only versus 16.45% (relative risk, RR = 2.61) and 80.76% (RR = 0.42), respectively, of the control population. The BF FB subtype frequency was 23.91% versus 7.57% in the control samples (RR = 3.88). We thus hypothesize that this polymorphic serum protein might be involved in the pathogenesis of allergic contact dermatitis to nickel.

Adolescent↗