Tissue plasminogen activator in the trabecular endothelium

By quantitative analysis of tissue plasminogen activator (TPA) in the trabecular endothelium, corneal endothelium, and iris in the eyes of monkeys and dogs, we found significant levels of TPA activity. In a [125I]fibrin-coated well assay, the levels for the dog and monkey were, respectively: trabecular endothelium, 0.2 and 0.5; corneal endothelium, 0.8 and 0.5 IU per mg protein. The iris tissue showed high TPA activity, but its protein content could not be measured with the techniques employed. Activity in the aqueous humor was not detectable. By the ELISA technique, the values (in ng TPA/mg tissue protein) for the dog and monkey were, respectively: trabecular endothelium, 0.16 and 0.44; corneal endothelium, 0.48 and 0.92. Again, iris tissue showed high TPA activity, whereas the aqueous humor showed low activity (0.86 ng/ml). The data obtained with the two methods showed a reasonable consistency, although a direct comparison was not possible because two separate standards were used. The presence of TPA in the trabecular endothelium, corneal endothelium, and iris may be important in modulating the resistance to aqueous outflow under normal conditions as well as those of hyphema.

Effects of Panax ginseng on blood alcohol clearance in man

1. Fourteen healthy male volunteers were studied to assess the effects of Panax ginseng on blood alcohol clearance, utilizing each subject as his own control. 2. At 40 min after the last drink, the blood alcohol level in the test group receiving ginseng extract (3 g/65 kg body weight) along with alcohol (72 g/65 kg body weight) was about 35% lower than their control values. 3. When the blood alcohol level was compared on individual bases, alcohol concentrations in 10 out of 14 test subjects ranged from 32 to 51% lower than their control values. 4. These results demonstrate that P. ginseng extract enhances blood alcohol clearance in man.

Effects of Panax ginseng extract on the benzo(a)pyrene metabolizing enzyme system

Ethanol extract of Panax ginseng C. A. Meyer, which has been used for centuries as a tonic in Asian countries, exhibited a selective induction of epoxide hydratase and cytosolic glutathione transferase activity without the concurrent induction of aryl hydrocarbon hydroxylase activity. Thus, Panax ginseng appears to have the potential to alter the metabolic patterns of benzo(a)pyrene and its reactive metabolites.

Tyrosine hydroxylase is expressed by neocortical neurons after transplantation

Tyrosine hydroxylase [TyrOHase; L-tyrosine, tetrahydropteridine:oxygen oxidoreductase (3-hydroxylating), EC 1.14.16.2], an essential enzyme in the synthesis of catecholamines, is expressed normally by neurons in the brainstem but not by those in mature neocortex. When embryonic neocortex is transplanted into adult neocortex, TyrOHase-immunoreactive cells develop and continue to be present in the transplants for the life of the host animal. The percentage of transplant neurons that express TyrOHase is highly correlated with the age of the embryonic donor tissue at the time of transplantation. Many TyrOHase-immunoreactive cells are present in transplants from embryonic day 12 (E12) embryos. The labeled cells are frequently arrayed in striking clusters of cell bodies and their processes, which ramify densely within the transplants. Moderate numbers of cells are found scattered throughout transplants from E14 donors, while E17 donors consistently develop small numbers of TyrOHase-containing cells. Tissue removed for transplantation on the day before birth (E19) never contains cells that express TyrOHase. The TyrOHase-positive cells are mostly bipolar and stellate in shape and show neither immunoreactivity for other catecholamine-synthesizing enzymes nor catecholamine fluorescence. These results provide a demonstration of continued TyrOHase synthesis in central nervous system cells that normally do not express this enzyme. Because of these and similar results with other neurotransmitter enzymes, the transplantation paradigm is particularly useful as a technique for studying the factors that regulate enzyme induction and activity during development of the nervous system.

Simple radiative transfer model for relationships between canopy biomass and reflectance

A modified Kubelka-Munk model has been utilized to derive useful equations for the analysis of apparent canopy reflectance. Based on the solution to the model simple working equations were formulated by employing reflectance characteristic parameters. The relationships derived show the asymptotic nature of reflectance data that is typically observed in remote sensing studies of plant biomass. They also establish the range of expected apparent canopy reflectance values for specific plant canopy types. The usefulness of the simplified equations was demonstrated by the exceptionally close fit of the theoretical curves to two separately acquired data sets for alfalfa and shortgrass prairie canopies.

Reproductive capacity of the mentally retarded

Ninety-seven mentally retarded females were studied to evaluate parameters of growth and development of secondary sex characteristics and the incidence of ovulation. These patients were selected on the basis of age and etiological classification. Patients were classified as Down's syndrome, brain damaged, or undifferentiated. The following parameters of growth and development were studied: anthropometric, bone age, and sexual maturation. Sexual maturation studies consisted of breast development, pubic hair, axillary hair, menarche, menstrual pattern, and ovulatory patterns. The following observations were made from this study: 1. Physical growth and secondary sexual development were retarded in all parameters. 2. The undifferentiated and brain damaged groups showed almost identical patterns of growth and development of secondary sexual characteristics. 3. The Down's syndrome group was the most retarded in physical growth and in secondary sexual development. 4. Skeletal age was a better guide than chronological age or height and body weight to the prediction of development of secondary sex characteristics and age at onset of menarche. 5. In 26 mentally retarded females who had achieved menarche the incidence of ovulation was approximately 60 percent.

Magnetism and Opaque Mineralogy of Basalts from the Mid-Atlantic Ridge at 45° N

The volcanic layer may be only 200 m thick at 45 degrees N and oxidation of titanomagnetite may be responsible for the decrease in amplitude of the magnetic anomalies away from the ridge axis.

Alkaline phosphatase activity of polymorphonuclear leucocytes and lymphocytes separated from normal human blood

Suspensions of polymorphonuclear leucocytes and lymphocytes were prepared from normal human blood by the glass bead column method of Rabinowitz (1964). The alkaline phosphatase activity of the separated cells was determined by biochemical and cytochemical techniques. Lymphocytes were found to contain an enzyme catalysing the hydrolysis of beta-glycerophosphate at alkaline pH but not of p-nitrophenylphosphate at the same pH and in the same buffer system. The alkaline phosphatase in polymorphonuclear leucocytes catalysed the hydrolysis of both substrates equally. The importance of this finding to the interpretation of clinical data is discussed.

The uptake and localization of tetracycline in human blood cells

The uptake of tetracycline by human blood cells has been investigated by means of fluorescence microscopy. The intense yellow fluorescence characteristic of the drug was found only in the leucocytes; the erythrocytes appeared uniformly dark. In both lymphocytes and polymorphonuclear leucocytes the nucleus exhibited more intense fluorescence than the cytoplasm. The importance of these results is discussed.

The effects of some drugs which induce agranulocytosis on the metabolism of separated human polymorphonuclear leucocytes and lymphocytes

1. Lymphocytes and polymorphonuclear leucocytes were separated from normal human blood by the method of Rabinowitz (1964).2. The oxygen uptake, lactic acid production and glucose uptake of suspensions of these cells in vitro were measured. The values obtained agree with published data using comparable techniques.3. Amidopyrine, chloramphenicol, chlorpromazine, phenylbutazone and thiouracil, in high concentrations, depressed the oxygen uptake of polymorphs, but not that of lymphocytes. With amidopyrine, chlorpromazine and thiouracil significant inhibition was produced by concentrations equal to therapeutic plasma levels. High concentrations of the drugs, except chlorpromazine, stimulated the glucose uptake of lymphocytes but not that of polymorphs. Tetracycline and sulphisoxazole were without effect on either parameter of leucocyte metabolism.4. Because of erythrocyte contamination the lactic acid production of lymphocytes could not be determined. Lactate production by polymorphs was not affected by any of the drugs studied.5. The significance of these results is discussed. It is suggested that there is a relationship between ability to induce agranulocytosis and effect on leucocyte metabolism in vitro.