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Clearance mucociliare per immagini
No full textThe main steps of the optical and electronic magnification are described in the article, from the simple lens to the modern microscopy. To the aim of the paper (consisting in furnishing images clarifying features dealing with cells and secretions characterising the capacity of the bronchial mucosa to clear damaging or anyhow extraneous inhaled substances) better images are furnished by the scanning electron microscope, the only able to give " tridimesional" views of the examined sample, thank to the freeze fracture technique. Images are so presented dealing with the ciliated carpet covering the epithelial surface of the bronchial mucosa, as well as with individual ciliated cells with apical appendices (cilia) catched in most different expressions of their metacronal movement (ciliary beating) aimed, in physiologic conditions, to pin and move with aise the supra-ciliary gel-layer of mucus due to the fact that they beat into a watery sol-layer. Other images represent non-ciliated cells, some of which provided with surface appendices much smaller than cilia (brush cells), some located at the base of the epithelium not reaching its surface (basal cells), and other provided with secretory activity, named goblet cells, in cartilagineous bronchi and in non-cartilagineous bronchioli, while in the most peripheral bronchioli the latter progressively decrease in number, while other more globous secretory cells named Clara cells progressively take their place. Rather rare images of goblet cells are here published, catched in the very moment of the mucus secretion, followed by emptying of the cell itself, with the mucus collected by the nearby cilia, phenomenon which initiates the important mechanism of mechanical airway defense known under the name of muco-ciliary clearance
Nasal ciliary beat frequency after insertion of septo-valvular splints
No full textOBJECTIVE: At present, endonasal paraseptal splints are devices frequently employed in rhinosurgery. We evaluated the local tolerance of a newly shaped device, the Guastella/Mantovani splint (G/M-SVS), with respect to the physiological mechanism of mucociliary clearance. STUDY DESIGN AND SETTING: The study involved 20 patients who underwent septoplasty and/or turbinoplasty or other nasal surgical procedures. A sample of ciliated cells was obtained by nasal brushing and was examined ex vivo to determine the ciliary beat frequency (CBF) and morphology, before and 15 days after surgery. RESULTS: Before surgery the mean CBF was 10.87 Hz ± 0.56 Hz and when splints were removed it was 10.25 Hz ± 1.9 Hz. Morphological evaluation of the ciliary motion after surgery demonstrated a normal, coordinated beat. CONCLUSIONS: The G/M-SVS does not appear to interfere with the physiological mechanism of mucocillary clearance since CBF remain within a normal range. SIGNIFICANCE: This is the first study that demonstrates an optimal tolerability and safety of the septo-valvular splints on nasal mucosa
Supplementation with antioxidants in Down syndrome : the effects on exhaled breath condensate (EBC) and serum
No full textEffects of long-term nasal continuous positive airway pressure therapy on morphology, function and mucociliary clearance of nasal epithelium in patients with obstructive sleep apnea syndrome
No full textObjectives/Hypothesis: The objective was to investigate the possible modification of nasal mucosa function and mucociliary clearance in a group of patients with severe obstructive sleep apnea syndrome receiving mechanical ventilation with long-term nasal continuous positive airway pressure (n-CPAP), without nasal diseases.
Study Design: The study design was experimental. Eight (six male and two female) nonsmoker patients were selected on the basis of two sleep questionnaires, were identified as needing n-CPAP therapy, and showed normal values of mucociliary transport time, ciliary beat frequency, and anterior rhinomanometry.
Methods: After a full polysomnographic examination, the authors recorded respiratory disturbance index (RDI), apnea/hypopnea index, nadir arterial oxygen saturation, and sleep stage. Every patient underwent pulmonary function test; arterial blood gas analysis; chest radiography; electrocardiography; ear, nose, and throat evaluation with rhinoscopy; anterior rhinomanometry; a saccharine test to measure the mucociliary transport time; and a brushing of nasal epithelium for study of ciliary beat frequency. All patients underwent polysomnographic examination in basal condition with overnight n-CPAP (without humidifier) and repeated this examination after 1 and 6 months with Auto CPAP (Autoset Res Care, Sidney, Australia) to titrate n-CPAP pressure and measure the new respiratory disturbance index.
Results: The mean basal respiratory disturbance index (number of respiratory events during sleep per hour of recording time) was 53.7 ± 21.5 events/h; after 6 months of n-CPAP therapy (mean value, 7.5 ± 0.7 cm H2O) the respiratory disturbance index was 5.7 ± 3.76 events/h. Values for nasal resistance, mucociliary transport time, and ciliary beat frequency were normal before and after the ventilatory treatment.
Conclusion: In the study group of patients with severe obstructive sleep apnea syndrome, the nocturnal use of n-CPAP without humidifier did not modify the function and mucociliary clearance of nasal epithelium
Effects of salmeterol on cilia and mucus in COPD and Pneumonia patients
No full textThe present study was performed to evaluate the effects of salmeterol xynaphoate on ciliary beat frequency (CBF) of nasal epithelium and on rheological parameters of tracheobronchial mucus. We studied 10 steady-state COPD patients, eight patients with community-acquired pneumonia and eight healthy subjects as controls. They underwent a nasal brushing of the inferior turbinate to study the CBF in basal conditions and following application of salmeterol at 10(-5), 10(-6), 10(-7) and 10(-8) M concentrations directly to the epithelial samples. We also collected sputum samples, in COPD patients only, by the technique for "protected expectoration" for the rheological assessment in basal conditions and following addition of salmeterol at 10(-5), 10(-6), 10(-7) and 10(-8) M concentrations. Only samples with basal viscosity values higher than 2000 mPa/s were admitted. Our results confirmed previous studies that demonstrate a ciliostimulating effect induced by salmeterol. The mean basal CBF was 11.18 +/- 0.75 Hz in control subjects, while the pathological subjects showed a markedly lower basal values: 8.64 +/- 0.88 Hz (p = 0.000) and 8.83 +/- 0.68 Hz (p = 0.000), in COPD and pneumonia patients, respectively. Salmeterol induced ciliostimulation in both patients groups as well as the healthy controls. The maximum increase in CBF, highly significant, was obtained at 10(-6) M concentrations of salmeterol, while this effect decreased at lower concentrations. Regarding the action of salmeterol on rheological parameters, a direct effect of salmeterol on mucus cannot been demonstrated and the described beneficial clinical effects on mucociliary clearance occurring in vivo are probably related to an indirect effect of stimulation of ciliary beat. This preliminary study suggests that, in addition to COPD, salmeterol could be a useful therapeutic agent in pneumonia also, for its positive effect on ciliary movement other than bronchodilation, but this finding needs further investigations
Discinesia ciliare primaria e s. di Kartagener: presentazione e comportamento clinico.
No full textLa Discinesia Ciliare Primaria è una malattia congenita rara (circa 1:10.000 nati) che si accompagna nel 50 % dei casi a situs viscerum inversus. Le manifestazioni cliniche variano secondo l'età considerata ed includono: anomalie di posizionamento degli organi interni, rinosinusite cronica, otite media catarrale, infezioni respiratorie ricorrenti e riduzione della fertilità.
La diagnosi viene effettuata sulla base di diversi tests diagnostici come la misurazione dell'ossido nitrico nasale, lo studio della motilità ciliare, l'analisi dell'ultrastruttura ciliare e l'esame genetico per lo studio delle mutazioni nei geni coinvolti (soprattutto DNAH5, DNAH11 e DNAI1).
Il trattamento della malattia è focalizzato sulla prevenzione delle infezioni respiratorie attraverso le vaccinazioni e la fisioterapia respiratoria per il drenaggio delle secrezioni tracheobronchiali; inoltre gli episodi di riacutizzazione infettiva devono essere prontamente trattati con antibioticoterapia
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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