Treatment of refractoriness to platelet transfusion by protein A column therapy

Ten thrombocytopenic patients (platelets < 10–24 × 10(9)/L) who were refractory to platelet transfusion were investigated for their responsiveness to staphylococcal protein A column therapy. Nine patients had previously been treated with steroids, intravenous immune globulin, and/or other forms of immunosuppressive therapy without improvement in their transfusion response. All patients were receiving multiple platelet transfusions without achieving 1-hour corrected count increments (CCIs) > or = 7500. Eight patients had antibodies that reacted with platelets and were directed against HLA class I antigens, ABO antigens, and/or platelet-specific alloantigens. Plasma (500-2000 mL) from each patient was passed over a protein A silica gel column and then returned to the patient. Patients received from 1 to 14 treatments. A positive response to protein A therapy was defined as at least a doubling of the pretreatment platelet count and/or two successive 10- to 120-minute posttransfusion CCIs > or = 7500. Following plasma treatments, 6 of 10 patients responded with daily platelet counts that averaged 48 +/− 11 × 10(9) per L as compared with counts of 16 +/− 7 × 10(9) per L (p < 0.0005) before treatment. Posttransfusion CCI values determined in four of these patients averaged 2480 +/− 810 and 10,010 +/− 3540 (p < 0.005) before and after treatment, respectively. In contrast, among the four unresponsive patients, platelet counts averaged 10 +/− 9 and 13 +/− 10 × 10(9) per L (p = NS), respectively, while posttransfusion CCIs were 700 +/− 1410 and 1520 +/− 2460 (p = NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of short-term hormone replacement in the treatment of obstructive sleep apnoea in postmenopausal women.

BACKGROUND--Women appear to be increasingly susceptible to snoring and sleep disordered breathing after the menopause. This observation, coupled with the considerable sex difference in sleep apnoea, may be explained on the basis of a protective effect of female hormones. This study was carried out to determine whether hormone replacement therapy has a role in the management of obstructive sleep apnoea in postmenopausal women. METHODS--The effect of short-term (mean (SE) 50 (3) days) hormone replacement therapy with either oestrogen alone or in combination with progesterone on sleep disordered breathing was investigated in 15 postmenopausal women with moderate obstructive sleep apnoea. The effect of treatment on the ventilatory response to hypoxia and hypercapnia was assessed in 10 patients. RESULTS--There was no reduction in the clinical severity of obstructive sleep apnoea after hormone treatment despite an increase in the serum oestrogen level from 172 (23) to 322 (33) pmol/l. There was a small but clinically insignificant reduction in the apnoea/hypopnoea index during REM sleep from 58 (6) to 47 (7). There was no difference in response between the oestrogen only group and the oestrogen plus progesterone group. Hypercapnic ventilatory responsiveness did not change with hormone treatment, but an change with hormone treatment, but an increase in hypoxic ventilatory responsiveness was observed. CONCLUSIONS--These data indicate that short-term hormone replacement is unlikely to have an effective role in the clinical management of postmenopausal women with obstructive sleep apnoea. The observed reduction in the apnoea/hypopnoea index during REM sleep, however, suggests that longer term treatment, or the use of higher doses, may have an effect.     

Imaging of the central nervous system in pediatrics and adolescence.

Magnetic resonance imaging (MRI) has taken its place beside computed tomography (CT) and ultrasonography in effective imaging of the central nervous system in infants and children. The major initial impact of MRI in pediatric neuroradiology has been the displacement or replacement of the more expensive and invasive procedures such as angiography, myelography, cisternography, and ventriculography. Ultrasonography remains the screening procedure for fetal and infant central nervous system abnormalities, whereas CT continues to be an effective brain screening technique after loss of the ultrasonography windows with growth of the child. The better the clinical information transmitted to the radiologist in advance of imaging of the patient, the more likely the clinician will receive valuable information in return.     

Adenosine as a vasodilator in primary pulmonary hypertension

BACKGROUND. The acute administration of vasodilator drugs to patients with primary pulmonary hypertension has been advocated to identify those with reversible pulmonary vasoconstriction. Unfortunately, the usefulness of the drugs currently available is limited by accompanying systemic hypotension. A vasodilator with effects confined to the pulmonary circulation would therefore be advantageous in such patients. METHODS AND RESULTS. The purine nucleoside adenosine was infused into the pulmonary artery in seven patients with primary pulmonary hypertension (baseline pulmonary vascular resistance [PVR], 442-1,295 dyne/cm/sec-5) to determine its effect on PVR. In all patients, there was a dose-dependent and significant reduction (mean maximal percent decrease from baseline, 38.9%; p less than 0.001) in PVR mediated through a decrease in pulmonary artery pressure and an increase in cardiac output. Systemic vascular resistance (SVR) also decreased, but the ratio of PVR to SVR decreased (maximal mean percent decrease from baseline) by 10.5% (p less than 0.025), indicating that adenosine has a preferential vasodilator effect on the pulmonary circulation when administered in this manner. CONCLUSIONS. Because of its pharmacokinetic and vasodilator properties, adenosine may have a specific role in the investigation of primary pulmonary hypertension.     

Effects of haloperidol on motor and cognitive functioning in aged mice

The effects of haloperidol on motor and functioning and cognitive functioning were studied in young (3-5 months old) and aged (20-22 months old) male mice by examining haloperidol-induced catalepsy and haloperidol-induced decrements in performance on a radial arm maze. The aged mice were much more sensitive to these adverse effects of haloperidol than were the young mice. Studies of the distribution of radioactivity from [3H]haloperidol to the brain indicated that the differences in sensitivity to this drug were not due to pharmacokinetic differences. The results demonstrate that mice are suitable for studies of aging-induced changes in the behavioral effects of neuroleptic agents.