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Biomedical subjects

D W Morrish

Publications and source records attributed to D W Morrish.

At least 19 recordsLinked to original sources
PubMed1992

Partial hydatidiform moles have impaired differentiated function (human chorionic gonadotropin and human placental lactogen secretion) in response to epidermal growth factor and 8-bromo-cyclic adenosine monophosphate.

OBJECTIVE: The null hypothesis is that partial hydatidiform moles have normal differentiated function (human chorionic gonadotropin and human placental lactogen secretion) in response to epidermal growth factor and 8-bromo-cyclic adenosine monophosphate. STUDY DESIGN: Two complete moles, 10 partial hydatidiform moles, and 19 normal first-trimester placentas in monolayer culture were exposed to 10 ng/ml epidermal growth factor, 1 mmol/L 8-bromo-cyclic adenosine monophosphate plus 1 mmol/L theophylline, or control. Human chorionic gonadotropin and human placental lactogen secretion was measured. Frequency of response to stimuli was compared by chi 2 analysis, and hormone secretion was compared by analysis of variance. RESULTS: Partial moles demonstrated reduced frequencies of response of human chorionic gonadotropin and human placental lactogen to epidermal growth factor (partial moles 2/8 and 2/8, respectively; normal placentas 16/19 and 7/18, respectively; p less than 0.025) and of human chorionic gonadotropin to 8-bromo-cyclic adenosine monophosphate (partial moles 3/5, normal placentas 13/16; p less than 0.005). CONCLUSION: Partial hydatidiform moles demonstrate impaired human chorionic gonadotropin and human placental lactogen secretory responsiveness to epidermal growth factor and cyclic nucleotides in comparison with normal first-trimester trophoblast.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1991

Similarities in long-term cultures of blood and bone marrow from patients with acute myelogenous leukemia.

Dexter-type long-term cultures (LTC) were initiated with peripheral blood (PB) and/or bone marrow cells from 11 patients with acute myelogenous leukemia (AML), and 2 with myelodysplastic syndrome in blastic transformation. Marrow and PB cells from normal subjects served as controls. Assessment of nucleated cells and clonogenic progenitors in the adherent and nonadherent fractions of LTC revealed active hemopoiesis for greater than 5 wks in 4 of 8 cultures of AML blood, and 4 of 7 of AML marrow. The morphology and kinetics of nucleated cells and progenitors with putative normal (granulocyte-macrophage colony-forming units or CFU-gm), and abnormal (blast) phenotype in LTC from AML blood were similar to those from AML marrow, and adherent cells positive for collagen I and III and vimentin were found in both types of LTC. Growth of CFU-gm colonies ceased by wk 5-8 in AML cultures, significantly earlier than in LTC of normal marrow cells (survival of greater than 10 wks), which may indicate derivation of the CFU-gm from a transformed clone or deficiency of stromal function in the leukemic state. In most AML blood and AML marrow LTCs, growth of abnormal (blast) colonies continued until wk 4-6. This study demonstrates certain similarities of morphology and function between LTC of AML blood and AML marrow cells. LTC may provide a useful model for further analysis of circulating primitive hemopoietic progenitor cells in leukemic states.

Blood Cells↗
PubMed1991

Preparation of fibroblast-free cytotrophoblast cultures utilizing differential expression of the CD9 antigen.

The leukemia-associated antigen CD9 is present on a variety of normal cells, with apparent variable expression on normal human fibroblasts. In this study, we demonstrate by immunoperoxidase staining and direct binding studies that the CD9 antigen is uniformly expressed on normal human fibroblasts grown from first trimester and term placenta, embryonic fetal fibroblasts, and from human adult and fetal skin fibroblasts. Higher CD9 expression was present on fetal cells. CD9 antigen was not present on trophoblast. Over 99% of fibroblasts could be absorbed onto antibody to the CD9 antigen conjugated to magnetic beads. By applying this selective immunoadsorption of fibroblasts to term placental cytotrophoblast preparations, we demonstrated that fibroblast contamination could be nearly completely eliminated. This is a novel technique for purifying primary trophoblast cultures and may have wider applicability in cell culture of other cell types.

Antigens, CD↗
PubMed1991

Painless thyrotoxic thyroiditis in association with ovarian and adrenal failure.

Polyglandular autoimmune syndrome (PGAS) type II is a disorder characterized by Addison's disease, autoimmune thyroid disease, and diabetes mellitus. In this report, a 19-year-old woman having Addison's disease, ovarian failure, painless thyroiditis, and an HLA type characteristic of PGAS II is described. Painless thyroiditis has been considered recently to have an autoimmune basis and has been reported previously in another patient with Addison's disease. The otherwise characteristic features of the patient in this case allow her to be classified as having PGAS II, thereby expanding the scope of reported autoimmune thyroid disorders in PGAS II.

Adrenal Gland Diseases↗
PubMed1991

Transforming growth factor beta 1 inhibits placental differentiation and human chorionic gonadotropin and human placental lactogen secretion.

Previously, no inhibitors of placental differentiation have been described. In this study, we determined the effect of transforming growth factor beta 1 (TGF beta 1) on cytotrophoblast differentiation. Monolayer cultures of pure cytotrophoblasts were exposed to 0.001-10 ng/ml TGF beta 1 with and without the presence of 10 ng/ml epidermal growth factor (EGF), an inducer of placental differentiation. Over 7 days of culture, in 11 separate experiments, phase contrast microscopy demonstrated marked inhibition of EGF-induced syncytial formation by TGF beta 1. Basal human (h)CG and h-placental lactogen (PL) release were reduced compared to control by fractions of 0.75 (TGF beta 1/control) and 0.54, respectively. EGF alone induced fractional (EGF/control) increases in hCG and hPL release of 2.46 and 2.68, respectively. However, this stimulation was significantly inhibited by 10 ng/ml TGF beta 1. Dose-response studies showed that maximal TGF beta 1 inhibition of EGF-stimulated hormone secretion occurred at 0.1 ng/ml or more TGF beta 1. Partial differentiation (syncytium formation) occurred despite the presence of TGF beta 1, suggesting a portion of cytotrophoblasts were committed to differentiation at the time of culture. We conclude that TGF beta 1 acts as a major inhibitor of trophoblast differentiation and concomitant peptide hormone secretion.

Cell Differentiation↗
PubMed1990

131I treatment of thyroid papillary carcinoma in a patient with renal failure.

Procedures for 131I ablation in renal failure are not known. In one patient receiving dialysis, detailed dosimetry and health safety aspects were obtained. The results showed insignificant contamination of equipment, but a surprisingly significant reduction in biologic half-life of 131I due to efficient dialysis extraction. The data indicate that 131I ablation can be done safely and easily during dialysis but that much higher 131I doses must be used to achieve equivalent results to those obtained in patients with normal renal function.

Adult↗
PubMed1990

Mechanisms of endocrine dysfunction in patients with testicular cancer.

To determine mechanisms of endocrine dysfunction in patients with testicular cancer, we performed static and dynamic testing of the hypothalamic-pituitary-testicular axis and testicular exocrine function in 13 patients and 11 normal control subjects, as well as in vitro studies of tumor tissue and remaining adjacent "normal" testicular tissue in the 13 patients. In tumor tissue, we demonstrated (a) elevated concentrations of total serum estradiol and serum estradiol not bound to sex hormone-binding globulin, (b) impaired spermatogenesis and sperm motility, and (c) blocking of multiple enzymes necessary for steroidogenesis. The data were consistent with a paracrine-endocrine mechanism in which tumor-produced human chorionic gonadotropin stimulates production of estradiol by "normal" testicular tissue but not tumor tissue, and the high estradiol levels then result in impaired spermatogenesis.

Adult↗
PubMed1990

The dual effect of epidermal growth factor upon human chorionic gonadotropin secretion by the first trimester placenta in vitro.

Epidermal growth factor (EGF) is believed to play an important role in the regulation of placental function. We have examined the effect of EGF upon first trimester (7-10 gestational weeks) placental hCG secretion and cellular differentiation using both static (explants and isolated cells) and kinetic (superfusion of explants) culture methods. In superfused explants, short (1-4 min) pulses of EGF increased both the rate and amplitude of spontaneous pulsatility of hCG. The frequency increased from 3/h to 5/h, and the amplitude increased compared to the control channels as calculated by the area under the curve. This effect was dose dependent and the concentration of 50 ng/ml, which was the lowest dose tested, was the most effective. In explants cultured for 24 h, EGF caused a 2-fold increase in hCG secretion, compared to control, P less than 0.05. In two different dispersed trophoblastic cell cultures, EGF added daily for the first week caused a 180% increase in hCG secretion, P less than 0.05. However, according to morphological criteria, i.e. light microscopy and vital staining, no significant effect upon the rate of differentiation to syncytiotrophoblast was observed in long-term cultures of one of these preparations. In conclusion, EGF plays a dual trophic role in stimulating hCG secretion in the first trimester. However, this effect is not dependent on cellular differentiation.

Cell Differentiation↗
PubMed1988

Absence of feedback inhibition of prolactin secretion by the prostate.

Previous observations in rodents and man have suggested the existence of feedback inhibition of pituitary prolactin secretion by the prostate. Thyrotrophin releasing hormone (TRH) tests performed in males before and after prostatectomy demonstrated no difference in prolactin or thyrotrophin (TSH) secretion. These data do not support the hypothesis of a prostate-pituitary feedback loop in the control of prolactin secretion. The results also imply that prostatic TRH acts in a paracrine manner.

Aged↗
PubMed1988

Ultrastructural localization of human placental lactogen in distinctive granules in human term placenta: comparison with granules containing human chorionic gonadotropin.

Human placental lactogen (hPL) is known to originate in the syncytiotrophoblast, as demonstrated by light microscopic peroxidase and immunofluorescent staining. However, ultrastructural localization of hPL has not previously been performed. In these experiments, immunostaining of electron microscopic sections using protein A-gold and avidin-biotin complex techniques was used to study hPL and human chorionic gonadotropin (beta hCG) localization in first trimester and term placentae. HPL was localized in many small (0.12-0.25 micron) granules. In contrast, beta hCG was found in large (0.40-1.2 micron) granule complexes. The results therefore demonstrate that these two hormones are stored in two morphologically distinct types of cytoplasmic granules. Since hPL and hCG have different secretory mechanisms, this methodology will be useful in studying these differing mechanisms in human placenta.

Chorionic Gonadotropin↗
PubMed1987

Immunolocalization of alpha and beta chains of human chorionic gonadotropin, placental lactogen and pregnancy-specific beta-glycoprotein in term placenta by a touch preparation method.

Touch preparations of human placenta yield cells retaining antigenic reactivity to immunoperoxidase stains for alpha and beta chains of human chorionic gonadotropin, placental lactogen, and pregnancy-specific beta glycoprotein. This method is a rapid and simple alternative to conventional frozen and paraffin-embedded sections for detection of placental peptides.

Chorionic Gonadotropin↗
PubMed1987

Demonstration of specific secretory granules for human chorionic gonadotropin in placenta.

Existence of secretory granules and exocytosis during secretion of human chorionic gonadotropin (hCG) in human placenta has been a point of controversy. Using two methods, the highly sensitive avidin-biotin complex (ABC) method and the protein A-gold technique, for immunochemical identification of beta-hCG on electron microscopic sections, we have examined placentas at 8-10 weeks gestation and at term for the presence of secretory granules. First-trimester placentas demonstrated plentiful syncytiotrophoblast cytoplasmic granules, some undergoing exocytosis, when stained using specific beta-hCG antiserum in the ABC and protein A-gold methods. Term placentas did not show positive reaction product. The data demonstrate that the classic secretory granule-exocytosis pathway mediates placental hCG secretion. However, clear morphological differences exist between placenta granules and hormone secretory granules observed in pituitary, consistent with known functional differences between these organs. This methodology will be useful for further studies of the secretory pathways for placental peptides.

Chorionic Gonadotropin↗
PubMed1987

Epidermal growth factor induces differentiation and secretion of human chorionic gonadotropin and placental lactogen in normal human placenta.

Human trophoblast differentiates by the fusion of cytotrophoblasts to form syncytiotrophoblast. To determine factors controlling this process, the effects of epidermal growth factor (EGF) on trophoblast differentiation were studied using long term serum-free culture of isolated trophoblast. Only trophoblast was present in the cultures, as demonstrated by positive immunoperoxidase staining with beta hCG, cytokeratin, and trophoblast-specific H315 monoclonal antisera and by the absence of contaminating endothelial cells, fibroblasts, and macrophages, as shown by negative staining with vimentin and OKM1 monoclonal antisera. EGF induced large sustained increases in hCG and human placental lactogen (hPL) secretion in a dose-dependent manner. The minimum effective dose was 0.1 ng/mL, and the maximum effective dose was 1 ng/mL. Light and electron microscopic studies showed EGF-induced differentiation of cytotrophoblast to form syncytiotrophoblast. DNA content and cell number did not change during the process. The formation of syncytia thus probably accounted for the increase in hCG and hPL secretion. We conclude that EGF causes morphological differentiation, but not cell proliferation, of trophoblasts, and the differentiation results in increased hCG and hPL secretion from the syncytia.

Cell Differentiation↗
PubMed1986

Critical factors in establishing monolayer cultures of normal human placental cells in serum-free medium.

Comparative studies have been performed to determine the best method for preparing monolayer cultures of normal human term trophoblast cells. The use of 0.25% trypsin-10 U/ml DNAse I provided the highest cell viability and greatest hormone production, but was critically dependent on the trypsin lot used. Cell function in culture was not improved with various substrata, nor did other factors (medium type, pH, red blood cell removal) affect the results. Optimization of dispersal and culture conditions permitted the trophoblast cells to survive with intact hormone secretion and response to secretagogues under serum-free conditions. These studies thus define the best methodology for establishing trophoblast cells in monolayer cultures.

Cell Separation↗
PubMed1985

Preservation of human chorionic gonadotropin and placental lactogen secretion and normal morphology following long-term culture of normal human placental cells.

In order to study the regulation of hCG and hPL secretion during gestation, a system for the preservation of the functional integrity of normal placental cells in long-term culture was established. Normal term placental cells were dispersed with 0.25% trypsin-500 units DNAse I and cultured in a monolayer in Dulbecco's modified Eagle medium with 10% fetal bovine serum. Normal cell morphology, basal hCG and hPL production and hCG responses to dibutyryl cAMP were preserved till 54 days of culture. This model may be useful for the study of long-term regulation of normal placental hCG and hPL synthesis and secretion.

Bucladesine↗
PubMed1979

Hypothalamic-pituitary-adrenal function in extrinsic asthma.

Hypothalamic-pituitary-adrenal function in a well-defined, carefully selected group of 25 patients with extrinsic asthma was assessed by measuring plasma levels of adrenocorticotropic hormone (ACTH) and of 11-deoxycorticol after administration of metyrapone and by measuring the level of cortisol following stimulation with cosyntropin. No difference was demonstrated between asthmatic subjects and 20 normal age-matched controls. In addition, neither the response of the level of ACTH nor of 11-deoxycortisol correlated with the duration of asthma or the severity as assessed in 23 patients by tests of pulmonary function. We conclude that there is no abnormality in hypothalamic-pituitary-adrenal function in patients with extrinsic asthma, and we suggest that previous data suggesting such an abnormality may reflect heterogeneous groups of patients, inaccurate methods, and the variability of normal responses to ACTH and stimulation with metyrapone.

17-Hydroxycorticosteroids↗