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J Tamir

Publications and source records attributed to J Tamir.

4 recordsLinked to original sources
PubMed1994

Physiological and neuropsychological effects of theophylline in chronic obstructive pulmonary disease.

The effect of oral theophylline on clinical course, exercise, neuropsychological performance and bronchial reactivity was studied in chronic airflow obstruction. Twelve patients with chronic obstructive pulmonary disease (COPD) [mean age 62.4 +/- 1.6 years (SE), and forced expiratory volume in 1 sec of 1.15 +/- 0.1 l] were randomized to 4 weeks treatment with oral theophylline followed by 4 weeks of placebo, in a double-blind fashion. During each period, patients underwent clinical evaluation, incremental exercise, a battery of neuropsychological tests measuring a wide range of cognitive functions, and an inhaled methacholine provocation. On the active drug (levels 9.5 +/- 1 mg/l), vital capacity and maximal breathing capacity were 16 +/- 7% and 20 +/- 7% respectively, higher relative to placebo (P < 0.04). Exercise capacity, as reflected by peak O2 uptake and the anaerobic threshold, improved 14 +/- 5% and 18 +/- 5% (P < 0.04). In contrast, bronchial responsiveness to inhaled methacholine and the mean scores on the neuropsychological tests were not significantly altered by the drug. Clinical symptoms were unaltered, but mild side effects were more common on theophylline. We concluded that in moderate to severe COPD, theophylline treatment, at the low range of the therapeutic dose, improves lung function and exercise capacity. This improvement is achieved with no detectable alteration of bronchial reactivity to methacholine and with no deleterious effect on cognitive functions.

Aged↗
PubMed1993

Tumor prostaglandin levels correlate with edema around supratentorial meningiomas.

The pathophysiological mechanisms to explain peritumoral edema have not been clarified. Multiple aspects of brain edema secondary to supratentorial meningiomas were prospectively investigated in a group of 29 patients who underwent surgery consecutively. Sixty-nine tumor samples were analyzed for prostanoid levels. Levels of 6-keto-PGF1 alpha, the stable metabolite of prostacycline, were found to correlate well with the extent of edema (r = 0.51, P < 0.01). The ratio, 6-keto-PGF1 alpha x PGE2/TXB2, was found to have the best correlation with edema index (extension/tumor volume) (r = 0.69, P < 0.005). A case of a hemangiopericytic meningioma with the largest edema extent within the study group also exhibited the highest level of 6-keto-PGF1 alpha (2420 pg/mg protein). Steroid treatment (dosage, duration of therapy, and their product) did not correlate with prostaglandin levels. These findings may explain the inconsistent clinical effects of steroids on meningioma-induced edema. Possible explanations for this phenomenon are discussed. Otherwise, histology, pathological features of tumor aggressiveness, or mechanical parameters, such as its volume, location, and insertion site, did not correlate well with edema parameters or with prostaglandin levels. Similarly, tumor water content, imaging parameters in computed tomography and magnetic resonance, and operative findings (including dissection plane, vascularity, and tumor firmness) did not correlate well with edema parameters. Although a direct cause-effect relationship between prostaglandins and peritumoral edema is not conclusively established, the circumstantial evidence of the ability of prostaglandins to induce vasogenic brain edema and the robust association with peritumoral edema is persuasive.(ABSTRACT TRUNCATED AT 250 WORDS)

6-Ketoprostaglandin F1 alpha↗