Reversed-phase high-performance liquid chromatography of prostaglandins--biological applications.
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Biomedical subjects
Publications and source records attributed to L Walker.
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The human beta2-microglobulin antigen-antibody system was used as a model to illustrate the versatility of a microradioimmunoassay technique using protein A-bearing Staphylococcus aureus Cowan I strain (SACI) bacteria as a non-specific immunoadsorbent in place of a second antibody. Experimental conditions are described for a sensitive microassay which makes it possible to process large numbers of samples more rapidly and with minimum handling. Furthermore, SACI coated with specific antibodies by mixing with unfractionated antisera are a versatile reagent not only for radioimmunoassays but also for use as molecular probes to characterize cell surface antigens. Antibody-coated SACI could be lyophilized and proved extremely stable in storage thus providing a unique advantage for use in binding inhibition assays and as versatile reagent for clinical and investigative immunology.
Both intact cortical tissue and isolated cortical cells from the adrenal gland of the rat were analyzed for 6-keto-PGF1 alpha, the hydrolysis metabolite of PGI2, using high-performance liquid chromatography and gas chromatography-mass spectrometry. 6-Keto-PGF1 alpha was present in both incubations of intact tissue and isolated cells of the adrenal cortex, at higher concentrations than either PGF2 alpha or PGE2. Thus, the cortex does not depend upon vascular components for the synthesis of the PGI2 metabolite. Studies in vitro, using isolated cortical cells exposed to 6-keto-PGF1 alpha (10(-6)-10(-4)M), show that this PG does not alter cAMP levels or steroidogenesis. Cells exposed to PGI2 (10(-6)-10(-4)M), however, show a concentration-dependent increase of up to 4-fold in the levels of cAMP without altering cortico-sterone production, ACTH (5-200 microU/ml) increased cAMP levels up to 14-fold, and corticosterone levels up to 6-fold, in isolated cells. ACTH plus PGI2 produced an additive increase in levels of cAMP, however, the steroidogenic response was equal to that elicited by ACTH alone. Adrenal glands of the rat perfused in situ with PGI2 showed a small decrease in corticosterone production, whereas ACTH greatly stimulated steroid release. Thus, while 6-keto-PGF1 alpha is present in the rat adrenal cortex, its precursor, PGI2, is not a steroidogenic agent in this tissue although it does stimulate the accumulation of cAMP.
This bibliography was developed by the Remarried Consultation Center of the Jewish Board of Family and Children's Services of New York City for our own use. Because there is a growing interest in remarriage and the new types of families this social phenomenon creates, we became convinced that the meager number of articles and books in this area would be of interest to others. We have focused our attention on the now common phenomenon of the remarried and those living together in a committed relationship situation. Some articles that were not designed as studies of remarriage situations are included because their content is pertinent to our subject. The bibliography is divided into six sections to facilitated reference use. It should be noted, however, that these sections are not rigid and that some items could readily have been included under two or more sections. Articles included cover publication dates through April 1978. The six sections are: I. Demography; II. Remarried Couples; III. Stepparents and Stepchildren; IV. Divorce as a Precursor to Remarriage; V. Children of Divorce in Relation to Remarriage; VI. Remarriage-Prophylactic and Therapeutic Aspects. Unfortunately we did not find sufficient material to warrant a section on theoretical aspects. We have tried to make this bibliography as complete as possible using two computer retrieval systems as well as our own search of the literature. If you are familiar with references we have missed, we should appreciate hearing from you.
Normative values were obtained for triiodothyronine and thyroxine from four species of Old World primate (chimpanzees, rhesus monkeys, African green monkeys and talopoin monkeys) and a single species of New World primate (squirrel monkeys) represented by two subspecies, Colombian and Bolivian. The Bolivian squirrel monkeys exhibited the lowest values for both triiodothyronine and thyroxine. Male talapoins had the highest levels of thyroxine. Significant differences were found in levels of triiodothyronine and thyroxine between males and females of the same species and between the two subspecies of squirrel monkeys. Triiodothyronine:thryroxine ratios were consistently lower in the males of all species examined.
Squirrel monkeys of 2 subspecies, Bolivian and Colombian, were removed from their mothers on the day of birth and nursery reared for up to 2 years of age. Infants were tested weekly for 12 weeks, then monthly for 1 year, and at 2 years of age. Tests included morphology (body weight, crown-rump length, and head measurements), behavior (reflexes, activity, reaction to the surrogate), and physiology (heart rate, respiratory rate, temperature and optokinetic nystagmus). Data show some likenesses and some differences between the 2 subspecies.
A series of 25 cases of human bites of the facial region has been presented. Treatment procedure has been outlined for use in both infected and noninfected cases. Three case histories have been outlined.
The size of IgG aggregate effective in the inhibition or arming of human effector cells for antibody-dependent cell-mediated cytotoxicity (ADCC) was investigated using heat- and alkalipolymerized rabbit IgG or purified antibody fractionated by gel filtration. In contrast to the inhibition of ADCC against chicken erythrocytes, which was marked when effector cell were pre-incubated with high molecular weight aggregates (19S or greater), small polymers were most effective in arming for cytotoxicity against antigen-coated chicken red cells. Our data also demonstrate that while the cytotoxic potential of armed cells is short-lived and rapidly lost during culture at 37 degrees C but not 4 degrees C, the reduced capacity of these cells to kill antibody-coated targets is not altered by similar incubation at 37 degrees C. The differences in the size of aggregate active in arming and inhibition, and the stability of the two phenomena are compatible with the hypothesis that large aggregates may cause more cross-linking and redistribution of effector cell Fc receptors than small polymers of IgG.
To investigate three possible causes of the acute hemolysis in the hemolytic-uremic syndrome, we studied prospectively 207 children and 34 adults with shigellosis in Bangladesh. Nineteen children showed acute hemolytic anemia, a leukemoid reaction, thrombocytopenia and oliguria; nine other had, in addition, a serum urea nitrogen level of over 100 mg per diciliter. Eight of the nine had pseudomembranous colitis, and six of the nine died. The frequency of bacteremia was similar in all grades of shigellosis. Circulating immune complexes were found in 10 of 20 patients with uncomplicated shigellosis and in four of six with severe hemolytic-uremic syndrome. Limulus assay for endotoxemia was positive in nine of 18 patients with hemolysis (50 per cent) and three of 61 with uncomplicated shigellosis (5 per cent) (P less than 0.001). These data support the hypothesis that severe colitis in shigellosis is associated with circulating endotoxin from the colon producing coagulopathy, renal microangiopathy and hemolytic anemia.
Iatrogenic addictions, in contrast to illicit drug addictions, are commonly maintained for years before being brought to the attention of mental health professionals. Typically, by the time treatment is sought, both the physiological addiction and its related psychological problems have encapsulated the patient's life-style. The case histories described here illustrate some of the problems which typify treatment of the iatrogenically drug-dependent patient. Psychotherapeutic strategies utilizing life review, assertion training, and didactic teaching of alternative pain relief methods are often useful. The use of methadone for brief or more extended periods is sometimes helpful as an adjunct to psychotherapy.
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A cell of lymphoid morphology capable of killing antibody-coated chicken erythrocytes was isolated from nonimmune mouse spleen using a combination of carbonyl iron treatment and glass bead column passage. This non-phagocytic effector cell, which is referred to as the nonadherent K (killer) cell, is distinguished from the non-phagocytic myeloid K cell described earlier (Greenberg, A.H., Shen, L. and Roitt, I.M., Clin. Exp. Immunol. 1973. 15:251) by its relatively weak surface adherence properties and low concentration within the mouse spleen. The cell is further characterized by its relatively large size, lack of theta or immunoglobulin determinants, the presence of Mg++-independent complement receptors, affinity for aggregated IgG2 myeloma proteins, inhibition by cytochalasin B and good survival in cell culture. The possible lineage of the cell is discussed.
The training of medical students in the subject of mental retardation is important in broadening the physician's role in dealing with chronic disability. A competency-based training model is presented which specifies competencies, achievement methods, and evaluation procedures for a clerkship. The focus for training is on developing practical skills and a positive orientation toward developmental problems. Evaluative measures for 12 students rotating through the clerkship showed positive knowledge and attitude changes. Competency-based training is recommended as a model for preparing physicians to serve as advocates and resources for persons with chronic conditions.
During a one year period, 78 patients at the Denver General Hospital required mechanical ventilation following injury. Thirteen patients were judged to have Respiratory Distress Syndrome. Of these, 9 had classic early onset RDS but, with intravenous fluid restriction following resuscitation, diuretics and careful mechanical ventilation, all recovered. Six patients, all of whom were septic, developed late onset RDS 5 or more days after injury; 5 died. Disparity between early and late onset of RDS is emphasized; the one with good, the other with dismal prognosis. The current need is to improve treatment of late onset RDS, which frequently is associated with bacterial infection.
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