ABSTRACT
The authors administered the growth hormone-releasing factor (GRF) stimulation test to 19 patients with major depression and 19 age- and sex-matched control subjects to test the hypothesis that a blunted growth hormone (GH) response to clonidine reflects a central alpha 2-adrenergic receptor subsensitivity in depression. GH response to GRF was significantly higher in patients with depression than in control subjects. This group difference was mainly attributable to three of the 19 depressed patients who exhibited markedly high GH responses to GRF. These results suggest that the blunted GH response to clonidine seen in patients with depression is not due to a pituitary defect in GH secretion.
Subject(s)
Depressive Disorder/diagnosis , Growth Hormone-Releasing Hormone , Growth Hormone/blood , Adult , Age Factors , Body Weight , Clonidine/pharmacology , Depressive Disorder/blood , Dextroamphetamine/pharmacology , Female , Growth Hormone-Releasing Hormone/pharmacology , Humans , Male , Receptors, Adrenergic, alpha/drug effectsABSTRACT
A model of Leptospira motility was recently proposed. One element of the model states that in translating cells the anterior spiral-shaped end gyrates counterclockwise and the posterior hook-shaped end gyrates clockwise. We tested these predictions by analyzing cells tethered to a glass surface. Leptospira illini was incubated with antibody-coated latex beads (Ab-beads). These beads adhered to the cells, and subsequently some cells became attached to either the slide or the cover glass via the Ab-beads. As previously reported, these cells rapidly moved back and forth across the surface of the beads. In addition, a general trend was observed: cells tethered to the cover glass rotated clockwise around the Ab-bead; cells tethered to the slide rotated counterclockwise around the Ab-bead. A computer-aided microcinematographic analysis of tethered cells indicated that the direction of rotation of cells around the Ab-bead was a function of both the surface of attachment and the shape of the cell ends. The results can best be explained by assuming that the gyrating ends interact with the glass surface to cause rotation around the Ab-beads. The analysis obtained indicates that the hook- and spiral-shaped ends rotate in the directions predicted by the model. In addition, the tethered cell assay permitted detection of rapid, coordinated reversals of the cell ends, e.g., cells rapidly switched from a hook-spiral configuration to a spiral-hook configuration. These results suggest the existance of a mechanism which coordinates the shape of the cell ends of L. illini.
Subject(s)
Leptospira/physiology , Cell Movement , Computers , Motion Pictures , RotationABSTRACT
This study was designed to assess the effects of the North Carolina Improved Pregnancy Outcome (IPO) Project on use of prenatal care and incidence of low birthweight among its primarily Black registrants . Weighted least squares and stratified analysis procedures were used to scrutinize vital statistics data for subpopulation effects. IPO services were received by 51.7 per cent of Black women in the counties served by the project. For all Black registrants , the risk of receiving less than adequate prenatal care was 55.1 per cent of that of the comparison group. For Black teenage registrants , the risk was even less: 37.2 per cent of that of the comparison group. Nevertheless, no corresponding effects on the incidence of low birthweight could be detected. The evaluation methods used in this study can be applied to programs for mothers and infants in other locales to generate useful and practical information for state-level decision-making.
