Effect of liver damage on the level of coagulation factor II, X and VII in human and bovine plasma.

The thrombin generation test using thromboplastin reagent and synthetic substrate for thrombin and determination of factors II, X and VII using chromogenic substrates were applied to bovine and human plasma from objects with liver disease. The liver damage was accompanied with a lowering of the concentration of at least one factor of the extrinsic pathway of prothrombin activation. Use of some of these methods for laboratory diagnosis of liver damage is proposed.

Effect of calf thymus histone and its fractions F2 and F3 on human lymphocyte stimulation by phytohaemagglutin.

The effect of exogenous calf thymus histone and its fractions F2 and F3 on blastic transformation of human lymphocytes stimulated by phytohaemagglutinin was investigated. It was found that histones can not only inhibit, but also potentiate phytohaemagglutinin-induced blastic transformation of lymphocytes. This effect depends on the amount of histones in the medium and most probably also on individual sensitivity of lymphocytes. The arginine-rich histone fraction (F3) displayed the greatest inhibitory effect on lymphocyte stimulation.

Interaction of histones with human serum proteins.

The authors describe the interactions of whole calf thymus histone and its fractions with the human serum proteins. Immunoelectrophoretic analysis revealed two types of interactions: 1) a decrease in the electrophoretic mobility of a whole, immunochemically uniform fraction, and 2) a decrease in the electrophoretic mobility of only some molecules of such a fraction. In this association, the arginine-rich histone fraction (F3) was found to be the most active. The findings are important for interpreting the results of biological treatments.

The "stright-jacket" syndrome in chicks. II. Mechanism of development.

In a longitudinal study including measurement of the pressure in the amniotic cavity, amniotomy, and planimetric evaluation of the size of the amniotic sac, we investigated the development of the "strait jacket" syndrome in White Leghorn chicken embryos injected intraamniotically (ia) or paraamniotically on the fourth day of incubation with histone or embryotoxic serum, with the following results. Hyperlordosis and eventration developed as an outcome of tonic contraction of the amnion, which was observed only three hours after ia administration. Contraction of the amnion caused elevation of the intraamniotic pressure, which, 12 hours after ia injection, attained a mean value of 22.4 Pa (2.3 mm H2O). This value was not only significantly higher than the mean for control embryos (3.9 Pa), but it was critically close to the mean fluid pressure in the brain vesicles. Loss of the latter overpressure caused the vesicles to collapse, and the walls shriveled and exencephaly developed. Paraamniotic injection was not followed by either contraction of the amnion, or significant increase in intraamniotic pressure. This did not prevent heart malformations and cranioschisis of various extent. The majority of cardiovascular malformations were probably the hemodynamic consequence of overfilling of the intraembryonic vascular bed, which was one of the early signs of the effect question. Cranial-vault defects can be causally associated with the formation of amnionic adhesion and fusion with the epidermal ectoderm. This observation stresses the significance of the embryonic membranes and the fluid pressures within them for the development of certain congenital deformities and concentrates attention on teratological study of substances that induce protracted contraction of smooth muscle.

Experiences with evaluation of immunosuppressive activity of alpha-globulin fraction of human blood plasma.

Presented are experiences with the determination of immunosuppressive activity of alpha globulin fraction of human blood plasma, crude (Cohn fraction IV), partially purified and so-called low-molecular isolates of these substances. For testing the following techniques were used: the lymphocytotoxic and lymphoagglutination test, rosette-inhibition tests with human lymphocytes and splenocytes of mice immunized with sheep erythrocytes, lymphocyte blastic transformation inhibition test using PHA stimulated cells as well as in the mixed culture, inhibition of haemolytic plaque formation tests, determination of GVH reactivity using regional tests in the popliteal nodes, determination of HVG reactivity by skin graft survival test, determination of the effect on formation of precipitins against soluble antigens. The best results were obtained with the determination of survival times for skin grafts and the regional test in the popliteal nodes Fairly reproducible results were obtained in experiments on influencing the humoral antibody response and inhibition of formation of precipitating antibodies. Of in vitro methods tests of inhibition of lymphocyte blastic transformation both after PHA stimulation and in the mixed culture are applicable. Fully unsuitable proved the rosette, lymphocytotoxic and lymphoagglutination tests. In vitro modification of haemolytic plaque formation tests. In vitro modification of haemolytic plaque formation test is unfit for testing the crude fractions or partially purified drugs, its in vivo modification seems more feasible provided a large panel of animals is examined.

Study on immunosuppressive activity of alpha-globulin fraction of human blood plasma.

Immunosuppressive activity of alpha-globulin fraction of human blood plasma (Cohn fraction IV) was studied to determine the possible clinical utilization of this fraction as such, purified, or as the starting material for isolation of the active factor. The ethanol fractions IV, isolated and waste in the production of blood derivatives were found to be directly inapplicable because of relatively low activity and poor solubility. Therefore purification experiments were done to remove the denatured proteins and lipids and to increase the specific activity, they were performed on laboratory scale using DEAE ionex chromatography, and on semipilot scale utilizing the principles of ethanol fractionation of plasma. From the viewpoint of technology, the latter procedure seems more feasible; partial purification yielded good solubility and somewhat higher specific activity. Under study are further techniques capable of eliminating the contaminating proteins with do not carry the immunosuppressively active component, as well as the effectivity of pasteurization at 60 degrees C/10 hrs., which seems indispensable with respect to inactivation of infectious hepatitis viruses and the potential clinical application. Experimental isolations of the active component have led immunosuppressively active low-molecular part, which, however, is chemically nonhomogeneous. Its subsequent subfractionation will be necessary.