Search PubMed⌕ Search

Biomedical subjects

W H Anderson

Publications and source records attributed to W H Anderson.

At least 73 records · Page 4Linked to original sources
PubMed1984

Follicle-stimulating hormone increases ovarian vein nonsteroidal factors with gonadotropin-inhibiting activity.

Normally cycling monkeys were treated with 50 IU/day of "pure" follicle-stimulating hormone (FSH) on days 1 through 11 of the menstrual cycle. Ovarian venous serum (OVS) was collected on day 10; then all right ovarian follicles were aspirated. On day 11, OVS was collected again. Gonadotropin-inhibiting activity was determined in each sample by measuring the suppression of gonadotropin secretion by rat anterior pituitary cells in culture. OVS obtained on day 10 suppressed basal FSH secretion by approximately 45% and luteinizing hormone-releasing hormone stimulated luteinizing hormone secretion by approximately 50% (P less than 0.05, versus castrate serum). On day 11, OVS from the left ovary continued to suppress gonadotropin secretion, whereas OVS from the right ovary demonstrated significantly less gonadotropin-inhibiting activity. These findings demonstrate that exogenous FSH increases OVS concentrations of a nonsteroidal ovarian factor(s) with gonadotropin-inhibiting activity.

Animals↗
PubMed1984

Computer graphics for digitally formatted images.

The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use.

Computers↗
PubMed1984

An on-line digital image management system.

The continuing increase in diagnostic examinations using digitally formatted image instrumentation imposes new requirements on the acquisition, display, transmission, recording, and archiving of all diagnostic data. The fabrication decisions and initial clinical testing of a prototype on-line, decentralized digital image management system are described. With this system, raw digital data can be viewed by multiple users as soon as it is acquired by an acquisition node and transmitted to a display node. Radiologists and clinicians have given this system a favorable reception.

Computers↗
PubMed1984

Effect of porcine follicular fluid on the postcastration secretion of gonadotropins in rhesus monkeys.

Porcine follicular fluid (pFF) contains a nonsteroidal factor(s) that modifies pituitary secretion of both FSH and LH under certain physiological and experimental conditions. The aim of this study was to further define the activity of pFF on basal and pulsatile gonadotropin secretion after bilateral oophorectomy in monkeys. Sexually mature female rhesus monkeys underwent bilateral oophorectomy during the early follicular phase of the menstrual cycle. For 10 consecutive days, beginning on the day of surgery, monkeys were given twice daily sc injections of 2.5 ml normal saline (group I, control; n = 3), 2.5 ml steroid-free pFF (group II; n = 3), or 5.0 ml steroid-free pFF (group III; n = 3). Blood was drawn daily for 32 days, beginning the day before castration. One day before and on days 6 and 20 after castration, monkeys were placed in a restraining chair, and blood samples were drawn every 15 min for 6 h via an indwelling venous catheter. All samples were radioimmunoassayed for FSH and LH. In group I, a significant increase in serum FSH and LH occurred on days 3 and 6 postcastration, respectively. A significant increase in serum FSH did not occur until day 13 postcastration in groups II and III. Serum LH was significantly increased on days 10 and 9 postcastration in groups II and III, respectively. The LH pulse frequency ranged from 60-105 min and did not change after castration in control or pFF-treated animals. The LH pulse increment was significantly increased on day 6 postcastration in group I, but not until day 20 postcastration in groups II and III. Only minor oscillations in FSH were found until day 20 postcastration, at which time there was no significant difference in FSH pulse frequency or increment among groups. These findings demonstrate that a nonsteroidal factor(s) in pFF suppresses basal FSH and LH concentrations and LH pulse increment in monkeys after surgical castration. Further, because LH, but not FSH, concentrations began to increase during pFF treatments, these data suggest a temporal disparity in the effects of pFF on FSH and LH secretory profiles.

Animals↗
PubMed1984

Serosuppression in experimental filariasis.

Both antigen specific and non-specific immunoregulation by cells have been described in jirds infected with Brugia pahangi, but the contribution of serum factors to immunoregulatory phenomena in this infection has not been examined. The present study determined the effect of serum from normal or B. pahangi infected jirds on the mitogen responsiveness of spleen cells from uninfected animals and on the antigen responsiveness of lymph node cells (LNC) from infected jirds. Addition of heat-inactivated jird serum to cultures of cells supplemented with 1% fetal bovine serum demonstrated that serum from chronically infected (greater than or equal to 20 weeks post-infection), but not normal jirds consistently suppressed responsiveness of LNC from infected jirds to B. pahangi extracts in a dose-dependent manner (0.25%-1% concentration). A comparison of sera from jirds at different times post-infection demonstrated that sera (1%) from chronically infected (30 weeks; 100% suppression), but not acutely infected (4 weeks; 0% suppression) or recently microfilaremic (10 weeks; 11% suppression) animals were capable of suppressing antigen reactivity of LNC. In contrast, the inhibitory effect of serum on lymphocyte reactivity to the mitogens, PHA and PWM, was observed intermittently throughout the course of the infection and was less than the effect of chronic serum on antigen responsiveness. The B. pahangi antigen response of spleen cells from infected jirds depleted of suppressor cells by fractionation over nylon wool was also inhibited by chronic sera. Following fractionation of chronic sera by Sephadex G-200 chromatography, suppressor activity was observed in the void volume and IgG peaks. Suppressor activity was not associated with protein A, anti-jird Ig, or B. pahangi antigen bound fractions, nor with polyethylene glycol precipitable material.

Animals↗
PubMed1983

The effect of prostaglandin E2 on histamine-stimulated calcium mobilization as a possible explanation for histamine tachyphylaxis in canine tracheal smooth muscle.

Isolated strips of canine tracheal smooth muscle rapidly lost their responsiveness to histamine when placed in a zero calcium Krebs buffer. Responsiveness to acetylcholine, however, was not rapidly lost, and following 120 min of incubation in zero calcium buffer with frequent washes, 10% of the contractile response still remained. The kinetics of each loss of response suggest that primarily a loosely bound source of calcium is mobilized by histamine and a more tightly bound source is mobilized by acetylcholine. Consistent with these data were the effects of the calcium antagonist verapamil. In normal calcium Krebs solution, dose-response curves to histamine were markedly reduced by verapamil while acetylcholine responses were relatively unaffected. In calcium depleted tracheal strips, indomethacin potentiated the calcium dose-response curve, determined by incremental readdition of calcium in the presence of histamine (10(-4) M), with comparatively little effect on the calcium dose-response curve in the presence of acetylcholine (10(-6) M). Also, in indomethacin pretreated tracheal strips, a reduction in the histamine-calcium dose-response curve could be produced by exogenous addition of 2.8 X 10(-9) M and 2.8 X 10(-8) M PGE2. In the acetylcholine-calcium responses there was a significant reduction only at 2.8 X 10(-8) M PGE2. These data suggest that histamine mobilizes primarily a loosely bound, possibly extracellular source of calcium necessary for contraction, and this histamine-stimulated calcium mobilization is sensitive to the effects of PGE2.

Acetylcholine↗
PubMed1983

An in vivo model for measuring antigen-induced SRS-A-mediated bronchoconstriction and plasma SRS-A levels in the guinea-pig.

1 Pharmacological modulation of antigen-induced anaphylaxis in actively sensitized guinea-pigs with intravenously administered indomethacin (10 mg/kg), pyrilamine (2.0 mg/kg) and propranolol (0.1 mg/kg) resulted in a delayed onset, slowly developing bronchoconstriction indicative of a slow-reacting substance of anaphylaxis (SRS-A) response. 2 Measurements of pulmonary mechanics on the drug-pretreated animals challenged with ovalbumin demonstrated a more prominent effect on dynamic compliance than resistance. This is consistent with the more potent effects of SRS-A on peripheral rather than central airways. 3 The slowly developing bronchoconstriction obtained after treatment with indomethacin, pyrilamine and propranolol was inhibited by the standard SRS-A antagonist, FPL 55712 and the SRS-A synthesis inhibitors, phenidone, BW 755C and nordihydroguaiaretic acid. 4 Plasma SRS-A levels were determined in guinea-pigs following antigen challenge. The appearance of SRS-A in the plasma preceded the onset of bronchoconstriction and SRS-A levels remained elevated throughout its development. Coincident with the inhibition of bronchoconstriction by the SRS-A synthesis inhibitor, phenidone, was a dose-dependent reduction in plasma SRS-A. The intravenous ED50 in each case was 4 mg/kg. 5 This model of antigen-induced SRS-A-mediated bronchoconstriction should prove useful for the in vivo evaluation and development of therapeutics which regulate the synthesis of SRS-A.

Animals↗
PubMed1983

Monoamine oxidase inhibitors in obsessive-compulsive disorder.

The authors describe the use of monoamine oxidase inhibitors (MAOIs) in eight patients with severe obsessive-compulsive disorder. In four cases, the MAOIs produced rapid and sustained remission of symptoms; no response was seen in four other patients. All patients who responded to MAOIs, but none of the nonresponders, had phobic anxiety and/or panic attacks. Thus, a trial of MAOIs is indicated in obsessive-compulsive disorder, especially when phobic anxiety or panic attacks form part of the clinical picture.

Adult↗
PubMed1982

Saline catharsis: effect on aspirin bioavailability in combination with activated charcoal.

The effect of a saline cathartic combined with activated charcoal or activated charcoal alone on aspirin bioavailability was characterized in six healthy volunteers. Using a random, Latin-square design, subjects were given 975 mg aspirin followed by either water alone, 15 Gm activated charcoal (AC), or 15 Gm activated charcoal plus 20 Gm sodium sulfate (AC + SS) separated by one week. Both AC (44.16 +/- 16.85 microgram/ml) and AC + SS (58.61 +/- 10.63 microgram/ml) decreased (P less than 0.001) the maximal plasma salicylate concentration (Cpmax) compared to control (86.61 +/- 12.69 microgram/ml). Urinary salicylate recovery was decreased (P less than 0.01) for AC (57.88 +/- 16.26 per cent) and AC + SS (61.00 +/- 11.49 per cent) as compared to control (93.73 +/- 6.83 per cent), while for area under the plasma concentration-time curve (AUC) only AC showed a decrease (P less than 0.01) compared to control. Neither AC nor AC + SS differed from each other for Cpmax, AUC, or cumulative urinary recovery. Our findings indicate that the addition of sodium sulfate to activated charcoal has no added effect on limiting aspirin adsorption relative to activated charcoal alone.

Adult↗
PubMed1982

Effects of toxin of red tide, Ptychodiscus brevis, on canine tracheal smooth muscle: a possible new asthma-triggering mechanism.

The red tide toxin produced by Ptychodiscus brevis becomes airborne by the thrashing action of the surf and wind and induces cough, rhinorrhea, watery eyes, and sneezing in normal humans and wheezing in asthmatic patients. The mechanism of the contractile response induced by P. brevis toxin (PBTX) was investigated with isolated canine tracheal smooth muscle. Tetrodotoxin and atropine blocked the contractile effect of PBTX, and neostigmine potentiated the contraction. Mepyramine, phentolamine, methysergide, and chlorisondamine did not inhibit the effect of PBTX. This is the first description of a naturally occurring airborne substance that causes smooth muscle contraction by stimulating the axon sodium channels, resulting in the release of acetylcholine at postganglionic parasympathetic efferent nerve endings. The in vitro effect of PBTX on canine tracheal smooth muscle indicates that PBTX is capable of causing respiratory irritation and thus may precipitate an asthmatic attack. It is possible, however, that the mechanism is vivo may also include stimulation of a cough receptor reflex and/or stimulation of sodium channels of afferent vagus nerve fibers. In vitro evidence suggests that isoproterenol, atropine, and verapamil may be used to eliminate or prevent the respiratory symptoms that follow exposure to airborne red tide toxin. The use of high-pressure liquid chromatography separated fractions indicates that the neurotoxic component, not the hemolytic component, is responsible for contractions.

Acetylcholine↗
PubMed1982

Effects of ketotifen, a benzocycloheptathiophene, on metacholine- and acetylcholine-induced contractions of canine respiratory smooth muscle.

The relaxant effects of ketotifen on isolated respiratory smooth muscle contracted by methacholine or acetylcholine were examined. Although potent dose-dependent relaxation was observed, it appears that more than 100 times the concentration is required to relax muscle contracted with cholinergic agonists than has been reported for muscle contracted by histamine. This observation offers a possible explanation for the findings of several investigators that dosages of ketotifen administered to patients protect against histamine-induced, but not methacholine- or acetylcholine-induced, bronchospasm.

Acetylcholine↗
PubMed1982

The cost of managing digital diagnostic images.

A study of the cost of recording and archiving digitally formatted diagnostic images is presented for an academic radiology department serving a 614-bed university hospital and a large outpatient population. The radiological examinations include computed tomography, nuclear medicine, ultrasound, and digital radiography. The archiving management strategies studied include the combined use of computer magnetic tapes, computer disc storage, and multiformat video film recordings. The estimated cost per patient for the archiving of digital diagnostic images is presented.

Archives↗
PubMed1982

A peripheralized digital image management system: prospectus.

The number of diagnostic radiology examinations being performed on digitally formatted imaging equipment is continually increasing. However, most digital data are recorded as analogue images and the films stored in a central file. The dynamic range of raw digital data is lost. Currently, the space and cost requirements for storage of all digital data have discouraged most users from attempting it. This article presents the concepts and describes the requirements and initial fabrication of a system that will capture and retain all digital data using a network of peripheralized image acquisition, display, and storage devices. Any piece of digitally formatted equipment can be interfaced into the system. A real-time computer capability provides that any digital examination can be reviewed at any display station for up to 10 days.

Computers↗
PubMed1982

Human blood monocytes and platelets share a cell surface component.

We describe a surface determinant shared by human monocytes and cells of the megakaryocytic axis that has been identified using a mouse monoclonal antibody. This monocyte-platelet antigen (MPA) is expressed on all (greater than 99%) of peripheral blood monocytes, platelets, and megakaryocytes. It is also expressed weakly on the monocytic cell line U937 and the promyelocytic line HL60 and is present on cells from 3 of 4 AML patients examined. It is absent from polymorphonuclear leukocytes, T and B lymphocytes, erythrocytes, and a panel of hematopoietic cell lines. MPA is stripped from monocyte membranes with pronase and is reexpressed overnight. The determinant is carried on a noncovalently linked biomolecular complex with molecular weights of 93,000 and 135,000.

Animals↗
PubMed1981

Continuous image recording using gray-tone, dry-process silver paper.

A method of recording continuous gray-tone images on dry-process silver paper from raster-scan video signals is described. The Tektronix 4634 image-forming module uses a fiber-optic faceplate cathode-ray tube to couple the light output onto the recording paper. The latent image is heat developed and presented in sheet form. An initial comparison between dry silver paper and conventional film for video-generated computed tomography and nuclear medicine examinations, shows little apparent difference in image quality. Considerable cost savings are possible when using dry silver paper. Additional cost savings are possible if multiple images can be recorded on each dry silver sheet.

Costs and Cost Analysis↗