HAEMODYNAMIC RESPONSES TO ANTAGONISM OF TUBOCURARINE BLOCK WITH ATROPINE-NEOSTIGMINE MIXTURE IN CHILDREN

Following antagonsim of tubocurarine block with a mixture ofatropine 20 µg/kg and neostigmine 50 µg/kg in 20children, heart rate decreased from a control value of 110.4beat/min to 90.1 at 5 min and 89.2 at 6 min (P<0.02). Strokevolume index did not change during the first 5 min from a controlvalue of 36.3 ml. beat^–1. m^–2 but a significantincrease to 48 ml. beat^–1.m^–2 was observed at the6th and 7th mins following the injection of the mixture (P<0.05).Cardiac index and mean arterial pressure remained unalteredthroughout the period of observation. Normal sinus rhythm wasmaintained in all patients. It was concluded that antagonismof tubocurarine with an atropineneostigmine mixture does notproduce any important haemodynamic change in children.     

The use of DNA markers for carrier detection and prenatal diagnosis of haemophilia A in Egyptian families

Summary. Haemophilia A is the most common inherited X‐linked recessive bleeding disorder. The aim was to investigate the usefulness of two DNA markers in linkage analysis, one intragenic BCL1 affecting restriction site in intron 18, and is detected as restriction fragment length polymorphism (RFLP), and one extragenic variable number of tandem repeat (VNTR) locus DXS52 (St14) to formulate an informative and accurate carrier detection and prenatal diagnosis. The study included 46 families with at least one child affected with haemophilia A, and 30 unrelated normal females as control group. Polymerase chain reaction (PCR) and restriction enzyme analysis were used to study the polymorphism in BCL1, and long‐distance PCR for detection of VNTR (ST14) alleles. The incidence of BCL1 (+) allele was 74%, 72% and 60% in patients, mothers and control group, respectively. Expected heterozygosity for BCL1 was 40% in mothers of affected cases compared with 48% in the female control group. However, observed heterozygosity was found to be 48% in the mothers of affected cases, compared with 60% in the control group. Thus, 48% of the studied families are informative for this marker alone. Nine different alleles of VNTR (St14) were observed in mothers and six alleles in affected cases and six in the control group. The most prevalent alleles were 1300 bp (45.5% and 34%) and 700 bp (13.6% and 20%) in patients and their mothers, respectively. Observed heterozygosity in mothers was 41% compared with 43.3% in controls. The combined use of both BCL1 and St14 markers raised the informative rate to 63.6%. Carrier detection and prenatal diagnosis is possible in haemophilia A families using both DNA markers. We suggest screening haemophilic families first for BCL1 polymorphism followed by analysis of St14 locus.     

PLATELET AGGREGATING ACTIVITY IN THE PLASMA OF PATIENTS WITH ESTABLISHED THROMBOSIS

This study examines the incidence and significance of novel plasma derived platelet aggregating activity (PAA) in 190 consecutive patients admitted to the medical wards of a general hospital. Seventy five patients (39%) demonstrated this activity. The incidence was highest in patients with a history of thrombosis (52%) or in those with a heightened thrombotic tendency, for example, patients with diabetes or hypertension. In contrast, platelet aggregating activity was observed in six out of 62 patients (approximately 10%) in whom a current or past medical history of thrombosis could not be elicited and in only two out of 72 healthy volunteers examined (3%). A high frequency of PAA was also noted in a small group of patients with idiopathic thrombocytopenia and patients who had previously received, platelet transfusions. In these patients, this activity presumably reflects the presence of antiplatelet antibodies. A good correlation between the presence of plasma derived platelet aggregating activity and the phenomenon of spontaneous platelet aggregation was observed. The platelet aggregating activity was not heparin dependent, but was completely abolished by EDTA (5 mM) and benzamidine (8 mM), or by pretreating the platelets with aspirin. A synergistic response was observed with subaggregatory concentrations of thrombin and adrenalin. Our results suggest that the presence of this platelet aggregating activity may provide a marker for vascular thrombosis. Furthermore we postulate that this plasma derived activity may be partly responsible for platelet hyperactivity previously observed in patients with thromboembolic disorders.     

SELLA SIZE AND CONTENTS IN SHEEHAN''S SYNDROME

High-resolution computerized tomography was used to assess the size and contents of the pituitary fossa in 57 patients with Sheehan's syndrome and 17 female control subjects. No correlation was found either in the patients or the control group, between sella volume and age, weight, height, parity or time interval from postpartum haemorrhage to scan. The sella volume showed wide variation. The mean sella volume for all patients was 565 mm3 (SD 292) in contrast to a mean volume for the controls of 922 mm3 (SD 155). The difference was statistically significant (P less than 0.001) using the Mann-Whitney test. The stalk was visualized in 46 patients (81%) (20 of these showed other pituitary tissue in addition). The remaining 11 patients showed no pituitary tissue, and only pure CSF density was observed.