ISSN:0025-7931    

DOI:10.1159/000196485

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

The airway secretions which line the respiratory tract form a biphasic layer composed of an aqueous ‘sol’ layer and a more superficial ‘gel’ layer. In the sol layer, also described as the ‘periciliary’ layer or ‘airway surface fluid’, the cilia beat and relax. The lubricant sol layer enables the gel mucus present at the tips of the cilia to be transported by the ciliary beating of the ciliated cells. Due to difficulties with sampling, little is known about the physical and biochemical properties of the sol layer. The gel layer is composed of high molecular weight glycoproteins (mucins) linked with proteins and lipids. They form a gel network with a high water content (95%) and rheologic and physical properties (viscoelasticity, adhesivity) adapted in normal conditions to protect the airway mucosa, particularly through mucociliary transport. The adhesive properties of mucus, which are influenced by its lipid composition and degree of hydration, are very important in controlling the efficacy of mucus transport through ciliary activity and coughing. An intermediate viscosity and elasticity is required for optimal mucociliary transport. In obstructive airway diseases, either of genetic origin, such as cystic fibrosis (CF), or acquired (acute or chronic bronchitis), and particularly during inflammatory and infectious episodes, mucus dehydration is associated with an increase in secreted or transudated molecules and with marked augmentation of DNA content. These abnormalities contribute to the increased viscosity and adhesivity of the airway secretions and are responsible for their abnormally low transport rate by ciliary activity and for inefficient cough clearance. In view of these alterations in the physical and functional properties of CF airway secretions, pharmacologic approaches should aim to rehydrate the mucus and to restore normal mucociliary or cough transport by stimulating chloride ion secretion (i.e. using UTP or ATP associated with amiloride in order to block sodium ion and water reabsorption). During acute episodes of infection, recombinant human DNase (rhDNase) may rapidly prevent mucus stasis by improving its rheologic properties. Lubrication of the mucus at the sol phase interface by ‘surfactant’ therapy may also represent a very promising therapeutic perspective to reduce the hyperviscosity and hyperadhesivity o

ISSN:0025-7931    

DOI:10.1159/000196486

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

We studied the ventilatory pattern and mouth occlusion pressure (P0.1) at rest and the response to awake hypercapnic stimulation in 27 patients with obstructive sleep apnea syndrome (OSAS). The respiratory pattern was characterized by both increased P0.1 and VT/Ti (p < 0.05), with a higher VE (p < 0.01) due to a slight increase in VT. Ventilatory response to hypercapnic stimulation showed no significant differences with respect to the control group. Our findings reveal that OSAS patients show an increased minute output secondary to a mild degree of hyperstimulation on the baseline central ventilatory control and that there is a subgroup of patients with a decreased ventilatory response to CO2.

ISSN:0025-7931    

DOI:10.1159/000196381

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

We hypothesized that since added airway pressure compresses bronchial vessels, the airway hyperemia found following airway injury would be reduced by positive end-expiratory pressure (PEEP). Accordingly, we measured the effect of 15 cm H2O PEEP on bronchial and pulmonary blood flows by the radioactive microsphere reference flow technique in closed chested goats (n = 7) before and after aspiration injury to the left lung with 0.1 N HCl. Thirty minutes after aspiration, the pulmonary blood flow to the injured left lung was reduced by one third, whereas the total bronchial blood flow to the left lung (normalized to mean systemic pressure of 100 torr) doubled (11.3 ± 2.2 to 20.6 ± 1.0 ml/mini00 torr; p < 0.01). Increasing PEEP from 5 to 15 cm H2O decreased total bronchial blood flow by about half both before (11.3 ± 2.2 falling to 5.7 ± 1.4 ml/min/100 torr) and after injury (20.6 ± 1.0 falling to 10.3 ± 2.7 ml/min/100 torr). The airway portion (down to 2-3 mm airways) of the total bronchial blood flow of the injured lung increased more than threefold (1.4 ± 0.5 rising to 5.5 ± 1.3 ml/min/100 torr; p < 0.01). This increased flow after aspiration was less affected by PEEP of 15 cm H2O (5.5 ± 1.3 to 2.8 ± 0.7 ml/min/100 torr, p = 0.09) than before injury (1.4 ± 0.5 falling to 0.5 ± 0.1 ml/min/100 torr; p < 0.05). The increase of the parenchymal portion of the bronchial blood flow after injury, although apparent (9.9 ± 1.8 increasing to 15.1 ± 1.2 ml/min/100 torr), was not significant (p = 0.08). However, 15 cm H2O PEEP halved this parenchymal flow (15.1 ± 1.2 to 7.5 ± 2.4ml/min/100 torr; p < 0.05). We conclude that within half an hour after acid aspiration of one lung its pulmonary blood flow falls by one third but its total bronchial blood flow doubles. The bronchial blood flow to the airway, the tissue most injured by the acid, increases more than the bronchial flow to the lung parenchyma. A PEEP level of 15 cm H2O essentially eliminates the compensatory increase in

ISSN:0025-7931    

DOI:10.1159/000196382

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

This study was conducted by the AFLM in order to determine the performance characteristics of 12 commercially available nebulizers (6 ultrasonic and 6 jet) used in the treatment of cystic fibrosis (CF). The nebulizers were connected to a circuit which simulated the ventilation of a CF child and CF adult, and were tested using three drug solutions: tobramycin (T), colistin (C), and amiloride (A). Nebulizer performance was evaluated according to the volume of drug solution delivered in 10 min during the simulated inspiratory phase (VI), drug granulometry (G%), drug concentration modification in the nebulizer reservoir (ΔC), and percentage of efficiently aerosolized drug (EA%). The ultrasonic devices delivered a significantly higher VI than the jet nebulizers (p < 0.0001) for all three study drugs. Ventilation rate did not influence VI. Regarding granulometry, higher percentages of T and A were found to be contained in droplets ranging from 0.5 to 5.0 µm following ultrasonic nebulization. Drug concentration modifications were independent of the nebulizer used but were influenced by drug type; overconcentrations of T and A were observed (ΔC = +10.5 ± 18.6 and +13.4 ± 8.9%, respectively). On average, the ultrasonic devices achieved a higher EA% than the jet nebulizers (17.3 ± 6.7 and 9.7 ± 9.6%, respectively). This study highlights the significant variability in performance of different nebulizer types and emphasizes the importance of accurately testing nebulizers prior to clinical use so that the most efficacious nebulizer/drug combinations may be pres

ISSN:0025-7931    

DOI:10.1159/000196488

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

A double-blind study versus placebo was performed to assess the effect of bamiphylline, a new xanthylic derivative, on tracheobronchial mucus clearance (TBMC) in smokers with simple chronic bronchitis and impaired mucus clearance as compared to normal controls. Twenty patients were enrolled and divided into two randomized groups. The first group was treated with bamiphylline (600 mg b.d.) for 15 days, while the second group received placebo with the same oral dosage regimen. Complete clinical-functional examinations were made before and after the test period to establish the effects of treatment. At the end of the study, only the group treated with bamiphylline showed a net increase in mucus clearance (mean radioaerosol elimination 28 ± 7% before treatment and 38 ± 11 % after treatment; p < 0.01) and an improvement in the clinical score and pulmonary function parameters, in particular the residual volume (RV = 3.41 ± 0.75 liters before treatment and 2.7 ± 0.6 after treatment; p < 0.01) and the forced expiratory volume at 1 s (FEV1 = 2.37 ± 0.7 liters before treatment and 2.88 ± 0.5 after treatment; p < 0.05). No side effects or adverse reactions that could be attributed to the study drug were obs

ISSN:0025-7931    

DOI:10.1159/000196383

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

Aerosol administration of antibiotics is an attractive approach to the treatment of the recurrent respiratory infections experienced by patients suffering from cystic fibrosis (CF). Through aerosol administration, drugs can, theoretically, be delivered directly to the target site of infection, i.e. the lumen of the lower respiratory tract, thus enabling smaller doses to be given. This, in turn, should result in reduced costs and decreased potential for systemic toxicity. The efficacy of aerosol antibiotic therapy is, however, influenced by numerous variables, including the type of nebulizer device used to deliver the aerosol, the drug’s physical properties, its concentration in the aerosol and particle size, carrier gas and patient factors. The efficacy of aerosol antibiotics in the treatment of CF is controversial. This appears to be due mainly to problems and inconsistencies with clinical trials. However, various antibiotics, including β-lactams, polymyxins and aminoglycosides, have demonstrated clinical benefits when administered by inhalation to CF patien

ISSN:0025-7931    

DOI:10.1159/000196489

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

Twenty-two consecutive patients with malignant pleural effusions (MPE) were treated with intrapleural Corynebacterium parvum 7.30; 2 of these died a few days after the treatment, and 10 had favorable responses. The other 9 patients had a PF pH < 7.30: all had favorable responses. The leukocytes, the lymphocyte subsets, the monocytes, the NK lymphocytes, and their PF/B ratios did not differ significantly before and after CBP treatment. Our study confirms that intrapleural CBP is an effective and simple method to control MPE. The combination of MP with CBP did not prevent effective pleurodesis and seems to reduce the frequency of adverse reactions, except fever.

ISSN:0025-7931    

DOI:10.1159/000196384

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

The association between abnormal chloride transport, resulting from mutations in the cystic fibrosis transmembrane regulator (CFTR) gene, and the immunologic processes involved in the development of CF lung disease is poorly understood. However, neutrophil-dominated inflammation on the respiratory epithelial surface is a common finding in CF patients and suggests a mechanism for the immunologic abnormalities described in CF. Of particular importance for the pathophysiology of CF are proteases such as neutrophil elastase (NE) which are released from neutrophils in CF airways and cause direct structural damage to respiratory tissue. In healthy individuals, the deleterious effects of excess protease activity in the respiratory system are inhibited by antiproteases such as α1-antitrypsin (α1AT) and secretory leukoprotease inhibitor (SLPI). However, in CF, antiproteases are outnumbered by proteases and this protective mechanism is rendered ineffective. Restoration of this protease/antiprotease balance through antiprotease replacement therapy is currently under clinical investigation and preliminary results are promisin

ISSN:0025-7931    

DOI:10.1159/000196490

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

The human respiratory syncytial virus (RSV) is often associated with airway obstruction and is suspected to induce bronchial hyperreactivity. Interactions of viral proteins with cellular components may be responsible for epithelial damage leading to bronchial hyperreactivity. In this study, we describe the localization of the 14.7-kD nonstructural protein 2 (NS2) in RSV-infected cells. The detection of NS2 was performed using antipeptide antibodies elicited against amino acids 109-123 of the predicted sequence of the NS2 protein. By using recombinant NS2, we could clearly demonstrate the specificity of the antipeptide antibodies. With this defined tool, NS2 could be first detected in infected HEp-2 cells at 10 h p.i. subsequently to the detection of N protein. In double-staining experiments, colocalization of NS2, P protein and N protein was demonstrated. The antipeptide antibodies recognized the NS2 protein in the sediment of RSV-infected HEp-2 cells lysed with RIPA buffer at 48 h p.i. The results agree with the reported interaction of RSV with cytoskeletal intermediate filaments. These interactions may implicate essential cellular functions suspected to induce bronchial hyperreactivity.

ISSN:0025-7931    

DOI:10.1159/000196385

出版商:S. Karger AG    

年代:1995

数据来源: Karger