1,721,074 research outputs found
Rhino-sinobronchial syndrome
No full textThe intra- and extra-thoracic airways have a common embryological origin - 2(nd)-4(th) branchial pouch - and a continuity that ensures the conditioning and the conduct of airflow to the alveoli. It is this continuity that explains the common pathological events having a cause and effect type of relationship, such as is the case with rhino-sinobronchial syndrome. This syndrome has a multifactorial pathogenesis frequently with an allergic component, for which the time for resolution can exceed 12 weeks - a fact which must be included in the differential diagnosis of severe and bronchial asthma, especially in cases of difficult management or resolution. Interaction between the pulmonologist and otolaryngologist is thus fundamental for a correct patient management
Antileukotrienes in clinical development for asthma.
No full textAsthma is a serious world health problem characterised by a chronic inflammatory disorder of the airways. Asthma attacks, or exacerbations, are episodic but airway inflammation is chronically present. Thus, this disorder requires long-term management. The goals of asthma management include prevention steps for long-term control, action steps to stop attacks, recognising deteriorating asthma, how to treat deteriorating asthma, how and when to seek medical attention and education. In order to achieve the best therapeutic choice, a stepwise approach should be adopted. In recent years, much progress regarding the characterisation of leukotrienes (LTs) has been achieved. These substances are important products of action of the 5-lipoxygenase (5-LO) enzyme on arachidonic acid (AA) and it has been established that the leukotrienes are key mediators of both allergy and inflammation. Consequently, the important role of the cysteinyl-leukotrienes (Cys-LTs) in the pathophysiology of bronchial asthma has been suggested. Pharmacological support for the role of Cys-LTs in asthma has been observed using inhibitors of 5-LO and specific LT receptor antagonists. In the clinical setting, the LT receptor, which plays the most important role, is the Cys-LT1 receptor. The antagonists of this receptor have proven an effective therapy in chronic asthmatics, agonist antigens and exercise-induced bronchoconstriction and in aspirin-intolerant asthmatics. These drugs provide a new approach in asthmatic therapy and therefore may facilitate the compliance of daily therapy
Assessment of airway occlusion by single breath N2 test and deflation lung PL-V curve in healthy subjects and COPD patients
No full textCyclic airway closing and opening may induce lung injury in both normal and diseased lung. During tidal breathing this phenomenon occurs when closing volume (CV) exceeds the expiratory reserve volume. In humans, CV is currently assessed from the onset of phase IV of the single breath nitrogen test (CVSBN), but this method fails in severe chronic obstructive pulmonary disease (COPD) patients in whom phase IV can be absent, even if the amount of airway closure should be substantial. At present, no agreement exists whether an another potential indicator of airways closure, the inflection point on the transpulmonary pressure–volume curve (CVPL-V) can be used as a surrogate of CVSBN, when phase IV is not detectable. The comparison of CVSBN with CVPL-V assessed during the same slow deflation showed that both in healthy subjects and in COPD patients, when CVSBN was present, it coincided with CVPL-V. In the young subjects in whom CVSBN was absent, CVPL-V was not detectable, in accordance to the notion that in these subjects lung recoil can be high enough to prevent airway closure in the whole vital capacity range. On the other hand, in the COPD patients with no phase IV, CVPL-V was constantly present, as expected. These results suggest that measurement of CVPL-V is a reliable method for closing volume assessment in both normal and COPD subjects. In the latter group, the measurement of CVSBN can lead to heavily underestimate the extent of the airway collapse
A quantitative analysis of plethysmographic loops
No full textContrary to healthy subjects, in whom the relation between alveolar pressure (Palv) and flow (V̇) is linear, Palv-V̇ loops are often seen in chronic obstructive pulmonary disease (COPD) patients. These loops contain potentially relevant information about the physiopathological phenomena that characterize this disease, but, at present, no quantitative data during spontaneous breathing are available.
This study has characterized plethysmographic Palv-V̇ loops in terms of inspiratory (Ains), expiratory area (Aexp), and sense of rotation in 130 stable COPD patients at rest during spontaneous breathing. Relative to Ains, Aexp was larger (1.29±1.74 versus 0.39±0.33 cmH2O L s-1), and its sense of rotation was compatible with time-constants heterogeneity, air trapping, recruitment/derecruitment of lung units or expiratory flow-limitation.
Aexp correlated with indexes of flow-limitation (RS= -0.274, P<0.01 with forced expiratory volume in one second) and gas trapping (RS= 0.321, P<0.01 with the ratio of residual volume to total lung capacity), but not with indexes of uneven distribution of ventilation as the alveolar volume measured during the single breath carbon monoxide test (RS= -0.081, P=0.36).
These results suggest that in COPD patients breathing spontaneously at rest, expiratory looping appears primarily because of the presence of tidal expiratory flow-limitation and eventually gas trapping, rather than because of time-constants heterogeneity or recruitment/derecruitment
Bronchoscopy in sarcoidosis : union is strength
No full textSarcoidosis is a benign disease of unknown etiology that is characterized by the formation of noncaseating epithelioid cell granulomas. Although a multisystemic disease, it primarily affects the lung and the lymphatic system of the body. When a histological diagnosis is required, bronchoscopy is frequently employed because allows tissue sampling from several anatomic sources, such as airways, lung parenchyma and hilar/mediastinal nodes. Transbronchial lung biopsies (TBLB), endobronchial biopsies (EBB) and conventional transbronchial needle aspiration (cTBNA) have long been the only bronchoscopic techniques to diagnose sarcoid granulomas, until the advent of endobronchial ultrasound guided needle aspiration (EBUS-TBNA). This technique shows excellent yield in sampling mediastinal adenopathies with a higher sensitivity than the conventional technique in sarcoidosis as well. Furthermore, non controlled studies, demonstrated its diagnostic superiority than EBB and TBLB in stages I (hilar adenopathies only) and II (hilar lymph nodes and parenchymal infiltrations) thoracic sarcoidosis. In a recent study, Gupta et al., randomized 130 patients with suspected stage I and II disease to undergo EBUS-TBNA or cTBNA in conjunction with transbronchial and endobronchial biopsies. The Authors demonstrated that the yield of cTBNA added to EBB and TBLB is similar to EBUS-TBNA plus transbronchial biopsies, although ultrasound guided transbronchial needle aspiration shows the best single diagnostic efficacy. In this review article we aimed to discuss the findings by Gupta in the context of medical literature, highlighting the importance of adding nodal aspirations (with or without ultrasound guidance) with bronchial and transbronchial samples to gain the optimal sensitivity in obtaining histological confirmation. We finally pointed out the need for future studies to evaluate the potential role of rapid on-site evaluation (ROSE) of needle aspirates in reducing additional sampling and related costs and complications
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
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