PubMed Health⌕ Search

Biomedical subjects

G D Schrank

Publications and source records attributed to G D Schrank.

9 recordsLinked to original sources
PubMed1994

Human atrial natriuretic peptide infusion and ovarian venous progesterone secretion in Yucatan micropigs.

Chronic indwelling catheters were implanted in the ovarian and external jugular veins of Yucatan micropigs during the luteal phase. Infusion of hypertonic saline (0.4 mol NaCl l-1) increased the concentration of porcine immunoreactive atrial natriuretic peptide in ovarian venous blood plasma by 0.61-1.81 fmol ml-1 more than that of the saline control group. Conversely, endogenously released porcine immunoreactive atrial natriuretic peptide was associated with low ovarian venous progesterone concentrations. Infusion of human atrial natriuretic peptide induced a dose-dependent increase in the progesterone concentration in ovarian venous blood. The results reported here suggest a duality in the ovarian response to atrial natriuretic peptide: a decrease in progesterone secretion in response to low concentrations and stimulated progesterone secretion in response to high concentrations of this peptide.

Animals↗
PubMed1984

Histologic documentation of gonococcal infection in the absence of a culturable organism.

The high incidence of negative routine cultures, in the presence of suppurative involvement of a joint suggested a possible role for alternative diagnostic techniques. Bedside cultures with hypertonic and anaerobic media were utilized to evaluate synovium and synovial membrane in gonococcal arthritis. This is the first histologic documentation of the diagnosis of gonococcal arthritis in the absence of a culturable organism.

Adult↗
PubMed1981

Particulate evaluation of parenteral nutrition solutions by electronic particle counting and scanning electron microscopy.

The particulate matter contamination of four commercial parenteral nutrition solutions that contained high concentrations of amino acids and dextrose was evaluated. Electron particle counting and scanning electron microscopy (SEM) were used to evaluate the amount of particulate matter over a 24-hour-period. The effect of adding 10 meq calcium and 20 meq phosphate electrolytes on the particulate content of these four solutions was determined also. Both counting methods agreed in the rank order comparison of particulate contamination, in that the Abbott and Travenol solutions contained the fewest particles while the Cutter solutions contained the most. The addition of calcium and phosphate resulted in at least a 50% increase in the mean particle count of all solutions. The SEM analysis showed the mean presence of microscopically large, yet subvisible, particles in the solutions containing phosphate and calcium. All of the solutions followed a previously published relationship between particle number and size. Although all of the solutions contained particulate matter, even the solutions with calcium and phosphate contained fewer particles than allowable by the USP-NF standard.

Drug Contamination↗
PubMed1979

Antisickling agents: effects of carbamyl phosphate or cyanate on survival, erythrocytes, and leucocytes in the mouse.

Equal mole doses of the anions of disodium carbamyl phosphate (carbamyl P) or sodium cyanate, antisickling agents, have been compared in C57B1 mice. Using 15 mice per group, two groups were given the equivalent ip dose of carbamyl P or cyanate anion (7 mmoles/kg/day) in a divided dose, in the morning and six hours later, for 17--18 days. The control group received sodium chloride (13.8 mmoles of Na+ or Cl-/kg/day). Surviving mice per group were sodium chloride, 15/15; disodium carbamyl P, 14/15; and sodium cyanate, 0/15, all mice died by day 2. Surviving mice appeared normal throughout the study, and no abnormalities were seen at necropsy. The hematologic measurements were the same for sodium chloride or disodium carbamyl P, including hemoglobin, packed cell volume, erythrocyte counts, leucocyte counts, and differential counts. The mean hemoglobin carbamylation was 1.24 (+/- 0.06 SE) moles of valine hydantoin/mole of hemoglobin tetramer in mice receiving disodium carbamyl P for 18 days, sufficient for antisickling activity. The enzymatic degradation of carbamyl P to NH3, CO2, and Pi was measured in serial blood samples in additional C57B1 and DBA/2J mice following ip injections of carbamyl P or cyanate. Both NH3 and Pi increased immediately after giving carbamyl P, but no increase occurred after cyanate administration. Thus enzymatic degradation of carbamyl P occurs in vivo and appears to be an important detoxification mechanism. When equivalent mole doses of anion are administered, disodium carbamyl P is less toxic than sodium cyanate in mice.

Ammonia↗
PubMed1979

In vitro attachment of Treponema hyodysenteriae to mammalian epithelial cells.

The interaction between Treponema hyodysenteriae and isolated swine intestinal epithelial cells or mouse adrenal cells in culture was examined. Studies were performed in which treponemes were incubated with each type of anomal cell in an atmosphere of 5% CO2 in air. Coincubation was terminated at various time intervals, and the percentage of treponemal attachment evaluated by light microscopy. The extent of attachment was dependent on both incubation time and temperature. The mechanism of attachment to the animal cell surface was examined by scanning electron microscopy. Interaction of the parasite with the host cell did not appear to alter cellular morphology or result in changes of the cell surface at the site of attachment. Preference for a cellular site of attachment was not found.

Adrenal Glands↗
PubMed1977

Purification of flagellar cores of Vibrio cholerae.

A procedure is described for the purification of the cores of flagella sheared from Vibrio cholerae. V. cholerae is a monotrichous organism whose flagellar core (FC) is enclosed within a sheath. The purification procedure consists of several cycles of differential centrifugation and cesium chloride density-gradient ultracentrifugation in the presence of a neutral detergent, Triton X-100. Purity of the FC preparations is assessed by electron microscopy, polyacrylamide gel electrophoresis, and chemical analysis. The purified FC preparations are devoid of flagellar sheaths and free from detectable cell wall and cytoplasmic contamination. Antibody prepared in rabbits against purified FC reacts with the flagellum of intact V. cholerae or purified FC as seen by ferritin-labeled antibody studies. Purified FC is composed of a single protein subunit with an estimated molecular weight of 45,000 g/mol and a density of about 1.3 g/cm3.

Bacterial Proteins↗
PubMed1976

Distribution of cholera organisms in experimental Vibrio cholerae infections: proposed mechanisms of pathogenesis and antibacterial immunity.

This study was undertaken to determine the sequence of events in the microenvironment of the intestinal tract that culminate in the symptoms of cholera and to attempt to define more clearly the mechanisms involved in antibacterial immunity. The extent to which mucus occurs in the normal intestine of rabbits and the appearance of the intestinal villi in unfixed frozen sections was demonstrated. The villi and intervillous spaces were found to be normally covered by a layer of mucoid material that formed a mucous zone between the intestinal contents and the tips of the villi. The distribution of cholera organisms in normal and immunized animals was demonstrated by the staining of frozen-tissue sections with specific fluorescent antibody. Study of tissue sections from normal animals showed that the onset of fluid accumulation was concomitant with the establishment of large masses of organisms in the intervillous spaces and crypts of the intestine after the successful penetration of this mucous zone. Tissue sections from animals actively or passively immunized against a cell wall antigen of Vibrio cholerae showed clumping of vibrios in the lumen and restricted distribution in the lumen and luminal border of the mucous zone. Antibody was not lytic in vivo.

Animals↗
PubMed1973

Differential medium for Vibrio cholerae.

A differential medium designed for rapid presumptive identification of Vibrio cholerae was described and shown to be useful for enumeration of viable cholera vibrios in the presence of other intestinal bacteria.

Cholera↗