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Biomedical subjects

D S Postma

Publications and source records attributed to D S Postma.

348 records · Page 20Linked to original sources

Outer hair cell loss and alterations in glycogen due to tobramycin sulfate.

A total of 26 albino guinea pigs were treated with 200 mg/kg/day of tobramycin sulfate. Animals were killed at various intervals of up to three weeks after seven days treatment. Outer hair cell (OHC) loss of the organ of Corti was evaluated by surface preparation techniques, and glycogen was assessed with PATCO- and PAS-stained sections. We have concluded that permanent damage of OHCs is most prevalent in areas that normally have the least amount and the smallest granule size of glycogen. With treatment, these susceptible areas are the least responsive in terms of an early increase in glycogen production. Furthermore, by 21 days after seven days of treatment, these same areas will reveal an almost total loss of glycogen at a time when damage is maximal.

Animals↗

Ototoxicity of tobramycin sulfate.

Fifty-four healthy guinea pigs were studied histologically for evaluation of Tobramycin sulfate ototoxicity. They were treated with 50, 100, 150 and 200 mg/kg/day under different schedules. Loss of hair cells occurred when dosage of 1,200 mg/kg was reached. Animals receiving 700 mg/kg were without damage to the inner ear. Outer hair cell loss occurred first in the basal turn, spreading upward. Inner hair cell loss began in the apical turn, progressing downward. When a total dose of 1,400 mg/kg was reached by (two) different schedules the higher daily dose produced about twice the hair cell loss; therefore, the ototoxic effect depends on the total dose but even more on the increased blood concentration.

Animals↗

Feasibility and effects of a home-care rehabilitation program in patients with chronic obstructive pulmonary disease.

PURPOSE: Pulmonary rehabilitation programs often show beneficial effects in patients with chronic obstructive pulmonary disease (COPD). These programs are usually hospital-based. This study assesses the feasibility and application of a 12-week Home-Care Rehabilitation Program (HCRP), carried out by general practitioners, physiotherapists, and home-care nurses. METHODS: Effects of the HCRP are assessed in 15 COPD patients with moderate to severe airflow limitation (inspiratory vital capacity [IVC]: mean, 75.4 [SD, 13.7] percent predicted, mean FEV1: 45.5 [6.9] percent predicted) and are compared with a stratified and randomized control group (n = 15). RESULTS: All participating disciplines judged the program to be useful and feasible. Patient compliance with the rehabilitation exercises was high. No major problems concerning the rehabilitation program were reported. After the HCRP, 4-minute walking distance improved significantly from 274 m [61] to 301 m [72] and maximal work load (W max), as measured during an incremental cycle test, increased from 75.3 W [24] to 85.3 W [28]. At equal work levels (W submax) during the cycle test both Borg dyspnea and leg effort scores decreased significantly after the HCRP (6.7 [1.3] versus 4.9 [1.7] and 4.2 [2.0] versus 1.7 [2.5], respectively). Changes in walking distance, dyspnea, and leg effort scores at W submax were significantly different between the two groups. IVC and FEV1 did not change significantly. In the control group, no significant changes in any parameter were observed. CONCLUSION: It was possible to design and perform successfully a home-care rehabilitation program, providing both objective and subjective improvements in a group of patients with COPD. A home-care rehabilitation program appears to be a valuable component in the management of COPD patients with a moderate to severe airflow limitation.

Aged↗

Management of plexiform neurofibroma of the larynx.

We report the ninth case of plexiform neurofibroma of the larynx, which occurred in a 2-year-old with multiple café au lait spots and obstructive sleep apnea. In discussing this clinical problem, we have attempted to make the following points. A patient's having more than six café au lait spots of greater than 1.5-cm diameter is diagnostic of von Recklinghausen's disease. It is much more difficult to completely excise plexiform neurofibroma than nonplexiform neurofibroma. The association of juvenile xanthogranuloma with von Recklinghausen's disease may be a risk factor for the later development of leukemia.

Child, Preschool↗