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311.
A combination of chronic obstructive pulmonary disease (COPD) and heart failure (HF) is common yet it is inadequately and rarely recognized. Because of the similar clinical manifestations, comorbidity is frequently not considered and appropriate diagnostic tests are not performed. It is very important that a combination of COPD and HF is recognized as these patients have a worse prognosis than patients with an individual disease. When present, COPD should not prevent the use of life-saving therapy in patients with HF, particularly β-blockers. Despite clear evidence of the safety and tolerability of cardioselective β-blockers in COPD patients, these drugs remain grossly underprescribed and underdosed. Routine spirometry and echocardiography in HF and COPD patients, respectively, is therefore warranted to improve current clinical practice.  相似文献   
312.
The lectin pathway of complement activation is initiated by mannan-binding lectin (MBL) or the ficolins through the common MBL-associated serine protease-2 (MASP-2). Deficiency of MBL has been associated with poorer outcome in cystic fibrosis (CF). We investigated the MBL pathway further by analysis of the MASP-2 deficiency mutation (D105G) as well as MBL-2 genotypes. Concentrations and genotypes of MASP-2 and MBL in 109 CF patients were correlated to lung function and chronic infections. We describe the first CF patient homozygous for the mutation, a girl with extremely severe lung disease with no other precipitating factors. We suspect total MASP-2 dysfunction to be a major modifier of CF lung disease. However, heterozygosity for the D105G mutation of MASP-2 had no correlation to MBL pathway function or poor lung function. Lung function was higher in the MBL deficiency determining genotypes (XA/YO+YO/YO) than in the other genotypes.  相似文献   
313.
Radulovic M, Schilero GJ, Wecht JM, Weir JP, Spungen AM, Bauman WA, Lesser M. Airflow obstruction and reversibility in spinal cord injury: evidence for functional sympathetic innervation.

Objectives

The first objective was to assess group differences for specific airway conductance (sGaw) among subjects with tetraplegia, high paraplegia (HP: T2-T6), and low paraplegia (LP: T10-L4). The second objective was to determine the significance of responsiveness to ipratropium bromide (IB) by the assessment of the inherent variability of baseline measurements for impulse oscillation (IOS), body plethysmography, and spirometry.

Design

Prospective cross-sectional intervention study.

Setting

James J. Peters Veterans Administration Medical Center.

Participants

Subjects (N=43): 12 with tetraplegia (C4-8), 11 with HP, 11 with LP, and 9 controls.

Interventions

Not applicable.

Main Outcome Measures

Measurement of IOS, body plethysmography, and spirometry parameters at baseline and 30 minutes after IB.

Results

Baseline sGaw was significantly lower in tetraplegia (0.14±0.03) compared with HP (0.19±0.05) and LP (0.19±0.04) patients. By use of minimal difference to evaluate IB responsiveness in tetraplegia, 4 of 12 and 12 of 12 subjects had significant increases in forced expiratory volume in 1 second and sGaw, respectively, whereas 11 of 12 and 10 of 12 subjects had significant decreases in respiratory resistances measured at 5 and 20Hz (R5 and R20), respectively.

Conclusions

The finding of group differences for baseline sGaw supports the hypothesis that human lung contains functional sympathetic innervation. Body plethysmography and IOS were comparable in detecting IB-induced bronchodilation in tetraplegia and significantly more sensitive than spirometry.  相似文献   
314.

OBJECTIVE:

To determine whether preoperative inspiratory muscle training is able to attenuate the impact of surgical trauma on the respiratory muscle strength, in the lung volumes, and diaphragmatic excursion in obese women undergoing open bariatric surgery.

DESIGN:

Randomized controlled trial.

SETTING:

Meridional Hospital, Cariacica/ES, Brazil.

SUBJECTS:

Thirty-two obese women undergoing elective open bariatric surgery were randomly assigned to receive preoperative inspiratory muscle training (inspiratory muscle training group) or usual care (control group).

MAIN MEASURES:

Respiratory muscle strength (maximal static respiratory pressure – maximal inspiratory pressure and maximal expiratory pressure), lung volumes, and diaphragmatic excursion.

RESULTS:

After training, there was a significant increase only in the maximal inspiratory pressure in the inspiratory muscle training group. The maximal expiratory pressure, the lung volumes and the diaphragmatic excursion did not show any significant change with training. In the postoperative period there was a significant decrease in maximal inspiratory pressure in both the groups. However, there was a decrease of 28% in the inspiratory muscle training group, whereas it was 47% in the control group. The decrease in maximal expiratory pressure and in lung volumes in the postoperative period was similar between the groups. There was a significant reduction in the measures of diaphragmatic excursion in both the groups.

CONCLUSION:

The preoperative inspiratory muscle training increased the inspiratory muscle strength (maximal inspiratory pressure) and attenuated the negative postoperative effects of open bariatric surgery in obese women for this variable, though not influencing the lung volumes and the diaphragmatic excursion.  相似文献   
315.
Sharma S  Brown B 《Lung》2007,185(2):113-121
Alteration in lung function at high altitude influences exercise capacity, worsens hypoxia, and may predispose to high-altitude illness. The effect of high altitude on lung function and mechanisms responsible for these alterations remain unclear. Seven adult male mountaineers were followed prospectively during a climbing expedition to Mount Everest, Nepal. Measurements of spirometry and respiratory muscle function were performed for the duration of the expedition, during changes in altitude between 3450 and 7200 meters (m). Measurements included the forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), maximal voluntary ventilation (MVV) in 12 seconds, maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and respiratory muscle endurance (Tlim). At an altitude of 3450 m, the FVC initially increased (9%) over 24 h, followed by a significant decline; the FEV1, MVV, MIP, and MEP showed similar progressive decline. At 5350 m, FVC increased by 21% over the first 48 h, then decreased. The FVC, FEV1, MVV, MIP, and MEP initially increased and then gradually diminished over time. Respiratory muscle endurance (Tlim) decreased over the first three days at 3450 m but then remained unchanged. MVV decreased at lower altitude followed by a slight increase and then a significant decline. Compared with baseline, we observed a fluctuating course for spirometric measurements, respiratory muscle strength, and endurance at high altitude. Initial transient increases in parameters occurred on ascent to each new altitude followed by a gradual decline during prolonged stay.  相似文献   
316.
This present trial investigated the efficacy of supplementation with Chlorella vulgaris, a bioactive microalga rich in macro- and micronutrients, in the improvement of biochemical and clinical symptoms in patients with obstructive pulmonary disorders. Ninety-seven patients with chronic obstructive pulmonary disease (COPD) or asthma who were under conventional treatment regimens were randomly assigned to C. vulgaris extract (CVE) (n=48; 2700 mg/day) or no adjunctive therapy (n=49) for eight weeks. Serum levels of antioxidants along with spirometric parameters and clinical symptoms were evaluated pre- and post-trial. The magnitude of increases in the concentrations of glutathione, vitamin E, and vitamin C, and activities of glutathione peroxidase, catalase, and superoxide dismutase enzymes were all significantly greater in the CVE vs. control group (p<0.05). In spite of increases, none of the assessed spirometric parameters (FVC, FEV1, FEV1/FVC, and FEF25–75%) did significantly differ by the end of the trial in the study groups, apart from a significant elevation of FEV1 in the control group (p=0.03). The frequency of coughing, shortness of breath, wheezing, and sputum brought up were all significantly reduced in both CVE and control groups (p<0.05). The rate of improvement for sputum brought up and wheezing were significantly greater in the CVE group compared to the control group (p<0.05). Although CVE was found to ameliorate serum antioxidant status, its supplementation was not associated with any bronchodilatory activity. The results of the present trial do not support any clinical efficacy for CVE in patients with obstructive pulmonary disorders.  相似文献   
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