1,720,995 research outputs found
Occupational asthma
No full textOccupational asthma (OA) is one of the most common forms of occupational lung disease in many industrialized countries, having been implicated in 9 to 15% of adult-onset asthma. Work-related asthma includes: 1. immunologic OA, characterized by a latency period before the onset of symptoms; 2. nonimmunologic OA, which occurs after single or multiple exposures to high concentrations of irritants; 3. work-aggravated asthma, which is pre-existing or concurrent asthma exacerbated by workplace exposures; and 4. variant syndromes. OA is important to recognize clinically, because it has serious medical and socioeconomic consequences. Diagnosis of OA should be confirmed by objective testing early after its onset. Removal of the worker from exposure to the causal agent and early treatment with anti-inflammatory drugs lead to a better outcome. Assessment of the work environment and identification of host factors may provide us with useful information about the mechanisms involved in OA. Another issue concerns strategies for preventing OA which should be implemented
Asthma induced by isocyanates: a model of IgE-independent asthma
No full textDevelopments in the understanding of causes and natural history of asthma induced by isocyanates may allow improved preventive strategies for occupational asthma (OA), and may also lead to improved understanding of mechanisms involved in IgE-independent nonoccupational asthma. Studies of genetic markers in OA induced by isocyanates suggest that HLA class II genes, glutathione S-transferase and NAT1 genotypes may predispose to development of this type of OA. Specific IgE antibodies against isocyanates are not always found in subjects with OA caused by isocyanates, leading most researchers to consider this type of OA, as a model of IgE-independent asthma. Evidence for cell-mediated immunity in OA induced by isocyanates has been provided by bronchoalveolar lavage, bronchial biopsy and induced sputum studies. The pathology of this type of asthma is similar to that of nonoccupational asthma, with cells such as eosinophils and T lymphocytes that exhibit signs of activation, and with thickening of the reticular layer of the basement membrane. Animal studies have shown that isocyanate asthma is driven primarily by CD4+ T cells and is dependent upon the expression of Th2 cytokines. However, animal models are not always reflective of human responses. OA induced by isocyanates similarly to nonoccupational asthma, is a multifactorial condition, and it is likely that complex gene-environment interactions play a role. Better understanding of these interactions is important for affected workers, and also has potential relevance for nonoccupational asthma
Occupational exposure and chronic heart failure severity
No full textLo scompenso cardiaco cronico (SCC) è una patologia
caratterizzata dall’incapacità del muscolo cardiaco di apportare all’organismo
una quantità di sangue adeguata ai bisogni metabolici e circolatori.
I principali fattori di rischio per l’insorgenza dello SCC sono:
ipertensione arteriosa, diabete, ipercolesterolemia, obesità, fumo, malattie
renali croniche.
È noto che alcune esposizioni lavorative, quali temperature estremamente
elevate o troppo basse, prolungata esposizione a rumore, vibrazioni,
pesticidi, ecc, possono contribuire all’eziologia di questa patologia.
Lo scopo del nostro studio è stato quello di valutare se l’esposizione
professionale può influire sulla gravità dello SCC.
Abbiamo condotto un’analisi retrospettiva sui primi 76 soggetti
fumatori di età superiore ai 65 anni, che si sono presentati al Centro
dello Scompenso che sono risultati affetti da SCC. I pazienti sono stati
divisi in quattro gruppi in base alle mansioni lavorative svolte: impiegati,
agricoltori, metalmeccanici e soggetti con esposizioni professionali
diverse (parrucchiera, fuochista, muratore, ecc.). I nostri risultati
hanno evidenziato che gli agricoltori hanno una frazione di
eiezione del ventricolo sinistro minore rispetto agli impiegati
(p=0.0045) pur non essendoci differenza di classe NYHA e/o di presenza/
assenza dei fattori di rischio dello SCC. Questi dati suggeriscono
pertanto che la mansione di agricoltore si associa ad una maggiore
gravità dello SCC
Espression of vasoactive intestinal peptide 1 receptor (VIPR1) in the central airways of smokers
No full textSubstance P in sputum of patients with chronic obstructive pulmonry disease and occupational exposure to respiratory irritants
No full textThe role of tachykininis in airway inflammation has been extensively demonstrated in experimental animal models, but evidence in humans is very sparse. The aim of this study was first to quantify the content of substance P (SP) in sputum of a group of patients, with chronic obstructive pulmonary disease and with exposure to occupational irritants. Secondly, to compare them with sputum SP content of a group of control subjects
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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