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R L Pardy

Publications and source records attributed to R L Pardy.

67 records · Page 4Linked to original sources
PubMed1982

Exercise testing in evaluation of patients for lung resection.

We studied, in a prospective fashion, whether exercise testing selected candidates for lung resection and predicted postoperative morbidity and mortality better than "standard" lung function tests. We confirmed that a low preoperative FEV1 and VC had prognostic significance for the development of postoperative complications. Poor exercise performance did not. Likewise, analysis of exercise performance did not discriminate in patients rejected for surgery from those in whom resection was successfully completed.

Aged↗
PubMed1982

The effects of inspiratory muscle training in patients with cystic fibrosis.

This study evaluated whether inspiratory muscle training (IMT) could increase inspiratory muscle strength and endurance and exercise performance in 11 patients with cystic fibrosis (CF) with moderately severe airflow limitation. The IMT consisted of breathing through an inspiratory resistance (IR) for 15 min twice daily for 4 wk, preceded or followed by a 4-wk control period. After IMT, there was an increase in inspiratory muscle strength measured by maximal inspiratory mouth pressure at functional residual capacity: 74 +/- 18 cmH2O before training to 81 +/- 12 cmH2O after training, mean +/- 1 SD, p less than 0.025, and in inspiratory muscle endurance measured by the maximal IR tolerated for 10 min. Limitation of performance in the progressive exercise test was related to increased airflow limitation and possibly to poor nutrition. Mean exercise performance during progressive or submaximal exercise testing did not change after training. It is concluded that this form of IMT improved inspiratory muscle strength and endurance, but had little effect on exercise performance in patients with CF.

Adolescent↗
PubMed1981

Inspiratory muscle training compared with physiotherapy in patients with chronic airflow limitation.

The effects on exercise performance of physiotherapy (PT) (8 patients) were compared with those of inspiratory muscle training (IMT) (9 patients) in severe chronic airflow limitation. Exercise performance was measured by 3 tests: the distance walked in 12 min, peak oxygen uptake on a progressive multistage exercise test, and endurance time at two thirds of maximal power output. Measurements were repeated after a 1-month control period during which no change was observed apart from an increase in the distance walked in 12 min in the PT group. The PT patients then performed graded exercise in a physiotherapy program 3 times weekly, whereas the IMT patients trained for 30 min daily, inspiring against a resistance. Measurements were repeated after 1 and 2 months of training. Physiotherapy was associated with insignificant increases in exercise performance, whereas IMT produced both an increase in endurance time and in the distance walked in 12 min. We concluded that a simple at-home training program of inspiratory muscles was more effective than this particular physiotherapy program in improving exercise performance of some patients with severe chronic airflow limitation.

Aged↗
PubMed1981

The effects of inspiratory muscle training on exercise performance in chronic airflow limitation.

Using a simple, inexpensive, at-home program, 12 patients with moderate-to-severe chronic air flow limitation trained their inspiratory muscles. All showed increased inspiratory muscle endurance with no change in inspiratory muscle strength. Seven of the twelve patients increased their endurance time for submaximal exercise beyond the 90% confidence limits determined by 2 pretraining tests (i.e., a more than 40% increase in endurance time). The same group of 7 patients increased the maximal power output (p less than 0.005) and peak oxygen uptake (p less than 0.05) on a progressive exercise test after 2 months of training and increased the distance walked in 12 min after both 1 (p less than 0.005) and 2 (p less than 0.005) months of training. In 6 of the 7 patients in this group, the pretraining submaximal exercise tests were accompanied by electromyographic changes heralding inspiratory muscle fatigue. Their increased endurance time post-training was associated with a delay or absence of these changes. In the other group of 5 patients, who showed no change in exercise performance with training, electromyographic changes heralding inspiratory muscle fatigue were never observed in submaximal exercise tests. We concluded that although the endurance of the inspiratory muscles of patients with chronic airflow limitation is increased, specific training of the inspiratory muscles is usually associated with improved exercise performance only in those who demonstrate electromyographic changes heralding inspiratory muscle fatigue during exercise.

Aged↗
PubMed1980

Quantitative demonstration of cell surface involvement in a plant-animal symbiosis: lectin inhibition of reassociation.

The freshwater hydra, Hydra viridis is normally associated with Chlorella-like, algal symbionts which inhabit the host's digestive cells. Under experimental conditions bleached hydra will reassociate with algae harvested from green hydra, but not from our cultures of wild type Chlorella or strain NC64A which when originally isolated from Paramecium bursaria was symbiotically competent. Because of its demonstrated selectivity, the reassociation process is hypothesized to involve a recognition interface whose active participants are the algae cell wall and the digestive cell membrane. The data presented here confirm the hypothesis and suggest some potential molecular characteristics of the interacting partners. Concanavalin A (Con A), a plant lectin, used widely for similar studies in other systems totally inhibits reassociation; Wheat Germ Agglutinin (WGA), ricin and Lens culinaris lectin do so to a lesser degree. These results are consistent with the hypothesis that glycoproteins on the cells' peripheries are involved in cell-cell recognition in this system.

Binding Sites↗
PubMed1977

Metabolic relationships between green hydra and its symbiotic algae.

1. Hydra that maintain algal symbionts evidenced three modes of metabolism depending upon the nutritional state of the host and the photoperiodic conditions under which the animals were maintained. Animals either fed or fasted but maintained in the dark exhibited an RQ of 0.725 indicating fat metabolism. When they were fed Artemia nauplii and maintained in the light green hydra exhibited a mixed metabolism of carbohydrate and fat which gave an RQ of 0.862. Fasting green hydra, when maintained in the light, showed a pronounced carbohydrate metabolism typified by an RQ of 0.970. 2. Aposymbiotic hydra, whether fed or fasted, exhibited an RQ of 0.725 indicating a high degree of fat metabolism. 3. Symbiotic hydra which were fed and maintained in the light demonstrated a respiration rate of 14.4 microliter/day per hydra, which was 2.5 times greater than animals (symbiotic or aposymbiotic) maintained under any other condition of fasting or photoperiod. It is hypothesized that the enhanced respiration observed in these animals is due to the metabolic activities of the symbiotic algae associated with reproduction and development. 4. Calculations based on respiratory measurements and indirect calorimetry suggest that hydra consume approximately 0.0320 calories per day and that symbiotic algae may supply up to 69% of the host caloric requirements via the translocation of approximately 5 microgram of carbohydrate when the host is fasting and light is provided.

Animals↗
PubMed1976

The morphology of green hydra endosymbionts as influenced by host strain and host environment.

The ultrastructure of Chlorella-like algal endosymbionts from the Florida and English strains of green hydra was compared under different host feeding and photoperiodic regimes. Under standard conditions (host fed daily, 12-h photoperiod) the algae from the 2 strains exhibited considerable differences. The English symbionts had a pyrenoid, compact chloroplast membranes and vesiculated polyphosphate bodies. By comparison, Florida symbionts lacked a pyrenoid, had chloroplasts with less compact membranes and exhibited spherical polyphosphate bodies. When maintained in the dark, algae from English hydra lost their pyrenoids, showed great compaction of the chloroplast and developed large, shield-shaped, electron-dense bodies. In contrast, algae from Florida hosts did not exhibit gross ultrastructural modification. Reciprocal cross-transfers of symbionts were made by placing Florida algae in English aposymbiotic (algal-free) hosts and vice versa. After residence in Florida hosts, English symbionts appeared to undergo ultrastructural modifications resulting in a morphology indistinguishable from the native Florida symbionts. Florida algae showed no modifications resulting from residence in English hosts. It thus appears that the English symbiont has great morphological plasticity, as its structure is greatly modified depending upon the host in which it resides and the conditions under which the host is maintained. The results of these studies are discussed and compared with published accounts of free-living Chlorella and with reports dealing with other Chlorella symbionts.

Chlorophyta↗
PubMedDate not supplied

Exercise testing in the assessment of pulmonary disease.

In this chapter, the different types of exercise tests and the indications for requesting a particular type of test have been discussed. The normal physiological responses to exercise have been reviewed and examples of the abnormal responses seen in a variety of disease states that have been discussed. The relatively small number of these responses limits the specificity of exercise tests in actually establishing a diagnosis, but can be helpful in narrowing the differential diagnosis. Perhaps exercise tests are most valuable in cases where the patient's symptoms are mainly limited to exercise and where investigations done at rest have failed to resolve a diagnostic question. When exercise testing is used under these circumstances, it serves a unique function in the diagnosis and management of pulmonary disease.

Asthma, Exercise-Induced↗
PubMedDate not supplied

An unusual example of Aspergillus species lung disease.

A 37-year-old man developed persistent hemoptysis after sustaining a gunshot wound to the right shoulder and lung. A right upper lobectomy was performed, in which Aspergillus species microorganisms were identified within retained bullet fragments. The role of infected bullet fragments in the pathogenesis of hemoptysis in this patient is discussed.

Adult↗