The influence of oral contraceptives on activated factor X inhibitor (XaI)-activity: a prospective study.

A prospective study of activated factor X inhibitor (XaI)-activity has been performed in women randomly allocated to contraceptive pills containing 30 micrograms + 150 micrograms (63 women) or 50 micrograms + 250 micrograms (44 women) ethinyl oestradiol and levonorgestrel, and a reference group of 35 women using other contraceptive methods. The XaI-activity was measured six times during 1 year of observation. There was a significant reduction of XaI-activity after 1 month of oestrogen consumption but there was no significant difference between 30 and 50 micrograms users. The maximal reduction during the observation period was 12% in both groups. There was positive correlation between the pretreatment value and the maximal reduction in the same patient, but the activity did not fall below the normal range (75-125% of normal human plasma).

Effects of gliclazide--a new antidiabetic agent--on blood platelet function in vitro and in vivo.

UNLABELLED: The effect of gliclazide on platelet activity was investigated and compared to that of tolbutamide and glipizide. IN VITRO STUDIES: adenosine diphosphate induced human platelet aggregation was inhibited by gliclazide in high concentrations (0.5--2.0 mg/ml). In the same concentration range tolbutamide exhibited a slightly less pronounced inhibitory effect. Collagininduced human platelet aggregation was inhibited by gliclazide, glipizide and tolbutamide in a concentration range of 0.5--2.0 mg/ml. Gliclazide had a similar effect on rabbit platelets. In vivo studies: Both acute and seven days administration of gliclazide to rabbits resulted in prolonged primary and total hemostatic plug formation time both in arterioles and venules. Similar results were obtained with tolbutamide and glipizide. Experiments with laser-induced platelet plug formation in the rabbit ear chamber demonstrated that 100 mg gliclazide/kg body weight and 25 mg gliclazide/kg body weight during 7 days significantly reduced the number of platelet emboli formed during 10 minutes after laser injury.

Medical ethics and child abuse.

The practice of good medical ethics is of particular importance in cases of juvenile maltreatment. In a number of court cases concerning battered children doctors' statements have been presented to the effect that maltreatment has not taken place. In twelve cases reported during the period 1971-75 the doctors' statement was misleading. In each of twelve cases it should have been the doctor's duty to record in his statement that this was a case of child abuse and/or neglect. It appears that as far as the individual doctor was concerned, he often state "these things should be dealt with by the child welfare authorities", who in their turn mereley referred to the doctor's statement. It is unlikely that this is maltreatment", the child welfare officer will reiterate. In six cases this statement was used in court before any evaluation had been made on the basis of the sequence of events. In all twelve cases the doctor had failed to make an adequate examination of the symptoms. It seems as if the doctor was not sufficiently interested in providing evidence of assault. In some cases, even, pathognomonic findings must have been kept secret. Psychological or emotional maltreatment need to be evaluated by a child psychologist who is a practical diagnostician. Injuries arising from physical abuse are most successfully diagnosed on surgical and casualty wards. Pediatricians must be cautious about dismissing diagnoses of maltreatment that have been established by other specialists, especially child psychologists.

The effect of platelet function inhibitors on experimental venous thrombosis formation in rabbits.

Inhibitors of the platelet functions, collagen-induced aggregation and release reaction (ASA and sulfinpyrazone) and ADP-induced aggregation (dipyridamole and VK 744), were investigated as potential preventive agents against venous thrombosis formation in rabbits. An experimental model combining endothelial damage (sodium morrhuate) and controlled stasis of the femoral venous flow was used. None of the agents showed any significant protective effect against venous thrombosis, a finding which is in keeping with the results of recent clinical investigation.

Grass allergens : a preliminary characterization by means of RAST-based allergen assay methods.

A preliminary study of a grass pollen allergens by means of radioallergosorbent test (RAST)-based assay methods has been made. A combination of gel filtration and ion exchange chromatography has been used to separate allergens, mainly from Festuca elatior, Lolium perenne, and Phleum pratense, into groups dependent on their molecular weight and net electric charges. A RAST-based titration method was used to detect and quantitate the different allergens. The specificity towards IgE of the different allergen groups was investigated by means of a RAST-based inhibition method. The allergen groups were found to be of a quite heterogenous nature when investigated by means of polyacrylamide gel electrophoreses. Furthermore, the different groups exhibited a considerable degree of cross-reactions when tested against a pool of patient sera by means of the inhibition method. This was the case even for allergen groups which differed significantly both in regard to molecular weight and net electric charge.

Examination of cocksfoot pollen (Dactylis glomerata) extracts by skin prick test in man, RAST-based allergen assay and protein content.

Three commercial preparations of cocksfoot pollen (Dactylis glomerata) from different manufacturers were compared by skin prick tests in man, allergen activity as measured by the RAST test and protein nitrogen unit (PNU) and total nitrogen (N) content. The skin prick tests were made on the forearm with the undiluted preparations and also with solutions of 1/5 and 1/25 dilutions. Three groups each of 9 subjects were tested and the sites for the 9 tests were determined by 3 different latin squares. Taking one of the preparations as having a potency of unity, the estimated potencies for the other two were 0.28 and 0.18 when the areas of the weals were measured by a graph paper method and they were 0.27 and 0.19 when the areas were calculated by taking the product of the longest diameter of the weal and that at right angles to it. No notable differences were observed when the solutions were inoculated at different test sites. The three preparations were ranked in the same order of potency by the skin prick test, by measurement of allergen activity as measured by a RAST-based allergen assay method using the sera of the test subjects, and by measurement of their PNU but not their total N content. Comparisons such as these could possibly lead to the production of allergen extract preparations of similar or with consistent potency.

Platelet reactivity ex vivo and in vivo after acute and chronic treatment with sodium caprylate.

The effect of sodium caprylate on platelet function and other hematological parameters was studied, using rabbits as experimental animals. Intravenous administration of caprylate resulted in a pronounced, although transient, inhibition of platelet reactivity as measured by the laser technique. A single oral dose of caprylate had no effect on platelet adhesiveness. Long-term oral administration of caprylate (2 and 3 weeks) to rabbits resulted in a progressive and significant decrease in platelet adhesiveness in these animals compared to that in a control group receiving saline. However, the platelet reactivity to laser damage was not changed after administration of caprylate for 3 weeks. Other hematological parameters such as hematocrit, plasma cholesterol, triglycerides, and ketone body concentrations were not altered by the treatment.