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Biomedical subjects

R T Morgan

Publications and source records attributed to R T Morgan.

At least 19 recordsLinked to original sources
PubMed1993

Maturation-dependent regulation of protein kinase C activity by vitamin D3 metabolites in chondrocyte cultures.

Vitamin D3 metabolites regulate the differentiation of chondrocytes isolated from the growth zone or resting zone of rat costochondral cartilage. Since some of the direct membrane effects of vitamin D metabolites are nongenomic, we hypothesized that protein kinase C (PKC) plays a role in signal transduction for these chondrocyte differentiation factors and that the regulation of PKC by the vitamin D metabolites is cell maturation dependent. Confluent, fourth passage cultures of growth zone and resting zone chondrocytes were treated with vitamin D3 metabolites for up to 24 h, lysed, and cell extracts assayed for kinase activity using a specific PKC substrate peptide. The addition of 1,25-(OH)2D3 to growth zone cell cultures resulted in a rapid dose-dependent stimulation of PKC, significant at 10(-9)-10(-7) M, beginning at 3 min and sustained until 90 min; 1,25-(OH)2D3 had no effect on PKC activity in resting zone chondrocyte cultures. The addition of 24,25-(OH)2D3 to resting zone cultures showed a slower PKC activation, with significant stimulation seen at 90-360 min for 10(-8)-10(-7) M 24,25-(OH)2D3. However, 24,25-(OH)2D3 had no effect on PKC activity in growth zone cell cultures at all times and concentrations examined. The specificity of PKC stimulation by the vitamin D3 metabolites was verified using a specific pseudosubstrate region peptide inhibitor, which reduced PKC activity when included in the reaction mixture. Pretreatment of the cultures with U73, 122, a phospholipase C inhibitor, decreased 1,25-(OH)2D3-stimulated PKC activity but had no effect upon 24,25-(OH)2D3-induced activity. The tyrosine kinase inhibitor, genistein, did not inhibit the PKC response in either vitamin D3 metabolites-treated culture. Neither actinomycin D nor cycloheximide affected 1,25-(OH)2D3-induced PKC activity in growth zone chondrocyte cultures, while both compounds inhibited 24,25-(OH)2D3-induced activity in resting zone chondrocyte cultures. The results of this study indicate that vitamin D metabolites stimulate PKC activity in a metabolite- and cell-maturation-specific manner. Effects of 1,25-(OH)2D3 appear to be nongenomic, whereas the effects of 24,25-(OH)2D3 probably involve a genomic mechanism.

24,25-Dihydroxyvitamin D 3↗
PubMed1989

Hospital at home.

True domiciliary health care services are not fully developed yet in Britain. The limited reports from this country and more extensive ones from abroad, indicate the potential of such schemes. The Peterborough Hospital at Home scheme (HAH) has been operating for 10 years and provides a valuable model for the development of a home care service. It has proved of particular value in a variety of patient groups. Terminally ill patients, those discharged early after operation, the elderly and children; all have derived benefits from home care. However, for a service to function efficiently, it must be of sufficient size, be fully integrated and organisationally responsive to changing needs and professional roles.

Community Health Nursing↗
PubMed1982

Peterborough Hospital at Home scheme.

The Peterborough Hospital at Home Scheme had explored the possibilities of treating at home patients who, if it were not for the scheme, would be in hospital. The scheme has been enthusiastically received by patients, consultants, general practitioners, nurses, and other health care workers. It is difficult to compare costs. Nevertheless, the cost of Hospital at Home care cannot be regarded as too expensive compared with care in hospital. Establishment of such schemes elsewhere would affect future allocation of capital.

Adult↗
PubMed1982

Multiple cell lines from patients with malignant melanoma: morphology, karyology, and biochemical analysis.

Of 23 cell lines representing 8 patients with malignant melanoma, one cell line from each patient has been extensively characterized by means of phase morphology, ultrastructural morphology, biochemical markers, steroid receptor protein analysis, and steroid hormone production. Extensive cytogenetic characterization was compiled from seven of the eight cell lines. The melanocytic derivation of the tumor cell lines was supported by the detection of the catecholamines epinephrine, norepinephrine, and dopamine. In addition, well-defined melanosomes were present in six of the seven lines whose ultrastructure were examined morphologically. None of the lines produced alpha-fetoprotein chorionic gonadotropin, or carcinoembryonic antigen in detectable amounts. The individuality of the cell lines was confirmed by phenotypic patterns of isozymes and by karyology.

Adult↗
PubMed1981

A human gallbladder adenocarcinoma cell line.

A continuous cell line, COLO 346, was established from a liver metastasis in a patient with adenocarcinoma of the gallbladder. COLO 346 grew as an adherent monolayer of pleomorphic epithelioid cells. COLO 346 cells produced esterone, but no estradiol, progesterone, or cortisol. No adrenocorticotropic hormones, beta-subunit of human chorionic gonadotropin, carcinoembryonic antigen, or alpha-fetoprotein production by the cells was detected. Cell doubling time was 36 h. Seven allelic isozymes were assayed. COLO 346 had a chromosome mode of 74 at 21 months postestablishment with 6 marker chromosomes present in 100% of the cells analyzed. COLO 346 has been in continuous culture for over 2 yr and is available to other investigators for their studies.

Adenocarcinoma↗
PubMed1980

Human cell line (COLO 357) of metastatic pancreatic adenocarcinoma.

A continuous human cell line, COLO 357, with exceptional characteristics was derived from a metastasis of a pancreatic adenocarcinoma. COLO 357 grew as an adhering monolayer with a cell doubling time of 21 h and grew with 10% clonal efficiency in soft agar. COLO 357 cells had numerous lamellar inclusions. The cells elaborated the pancreatic enzymes trypsin, elastase and chymotrypsin. COLO 357 also secreted appreciable amounts of carcinoembryonic antigen and human chorionic gonadotropin. COLO 357 had a chromosome mode of 53 with 20 identifiable Giemsa-banded marker chromosomes. Nine nucleolar organizing regions were found by silver-stained metaphase preparations. COLO 357 has been "fingerprinted" for seven allelic isozymes. This cell line has been maintained in active culture for over 2 years, is preserved in a cell bank, and is available to other investigators.

Adenocarcinoma↗
PubMed1980

Characterization of cell lines from four undifferentiated human malignancies.

Tumor tissue from 4 patients with undifferentiated malignancy was studied by means of electron microscopy and cell culture. The cell lines were characterized for morphologic and ultramorphologic appearance, chromosome constitution, and cell products. Cell types established in culture were compared to histologic diagnosis of the original tumor. In only 1 case originally diagnosed as malignant melanoma were cell cultures and ultrastructure consistent with that diagnosis. Two cases in which cell cultures and ultramorphologic appearance were consistent with melanoma were originally diagnosed as carcinoma and sarcoma. The tumor of the fourth patient, diagnosed as melanoma, had no features in the cell cultures and electron micrographs consistent with melanoma. The reliability of using the presence or absence of melanosomes alone as an absolute diagnostic criterion is doubtful.

Adult↗
PubMed1980

A human liposarcoma cell line producing hyaluronic acid.

A human liposarcoma cell line COLO 222, derived from a primary tumor in a 62-year-old male, elaborates hyaluronic acid. COLO 222 is characterized on the basis of histochemical, ultramorphological, and cytogenetic properties, along with isozyme phenotype and cell products. A chromosome mode of 53 predominates and unique Giemsa-banded marker chromosomes are identified. An autochthonous lymphoid cell line, COLO 143v, was established after the addition of exogenous Epstein-Barr virus. Cytogenetic analysis of Colo 143v is consistent with a normal male karyotype. COLO 143v possesses B-cell characteristics. This autochthonous system had been used for immunological studies and cytotoxicity assays.

Cell Line↗
PubMed1980

Estrogen receptor proteins in diverse human tumors.

One hundred three diverse benign and malignant human tissues have been assayed for estrogen receptor proteins. Receptors were detected in many endocrine and nonendocrine tumors. Tissues with estrogen receptor activity included four of five male breast carcinomas, 11 of 14 malignant melanomas, four of eight colon carcinomas, five of seven renal carcinomas, and various sarcomas and benign and normal tissues. Some tumors also had progesterone, androgen, and/or glucocorticoid receptors. These results suggest the use of hormones and hormone antagonists for therapy of a broad range of human cancer. Clinicians of diverse expertise should be aware of, and responsive to, potential endocrinological involvement in many dissimilar disease states.

Adolescent↗
PubMed1979

Comparison of four new cell lines from patients with adenocarcinoma of the ovary.

Permanent human tumor cell lines COLO 110, COLO 316, COLO 319, and COLO 330 were established from four patients with serous cystadenocarcinoma of the ovary. COLO 110 was derived from primary tumor tissue; COLO 316, COLO 319, and COLO 330 were derived from cells in malignant effusions. COLO 110 and COLO 316 grew as monolayers of epithelioid cells in culture; COLO 319 and COLO 330 grew as vermiform, floating colonies of epithelioid cells in culture. Epithelial-like morphology was confirmed by transmission electron microscopy. All four cell lines had marker chromosomes and double minute chromosomes. Giemsa banding revealed chromosomes 1, 3, 6, and 7 were involved in markers in all four lines, and chromosomes 2, 4, 5, 9, 11, and 15 were involved in markers in three of the cell lines. Marker chromosomes with possible homogeneous staining regions were observed in COLO 319. Estrone was elaborated by three of the lines, but neither chorionic gonadotropin, carcinoembryonic antigen, nor estrogen or progesterone receptor proteins were detected. Each cell line demonstrated a distinctive isozyme phenotype. These cell lines are maintained in active culture and in a cell bank for distribution to other investigators.

Aged↗
PubMed1979

Cell lines from human colon carcinoma with unusual cell products, double minutes, and homogeneously staining regions.

Two human colon carcinoma cell lines derived from the same tumor specimen were characterized. The cell lines, COLO 320 and COLO 321, have amine precursor uptake and decarboxylation cell properties, such as ectopic production of norepinephrine, epinephrine, serotonin, adrenocorticotropic hormone, and parathyroid hormone. The cells were morphologically different from most colon cell lines. Double minutes (DM) were initially present in nearly 100% of the metaphases. In a few subcultures of COLO 320, DM have persisted for 1.5 years. However, in COLO 321 and some subcultures of COLO 320, a loss of DM was observed and new marker chromosomes with homogeneously staining regions were observed. These unusual cell lines should be valuable for studies of apudomas of the colon and the cytogenetic phenomena of DM and homogeneously staining regions.

Animals↗
PubMed1978

A transitional cell carcinoma cell line.

A transitional cell carcinoma cell line, COLO 232, was derived from a primary urinary bladder tumor in a Caucasian male. In culture, COLO 232 retained distinct uroepithelial phenotypic traits and produced both carcinoembryonic antigen and adrenocorticotropic hormone. COLO 232 had a chromosome mode of 58 and retained the X and Y chromosomes. Ten marker chromosomes were identified. COLO 232 will be of value for biochemical and immunological studies.

Adrenocorticotropic Hormone↗
PubMed1977

Marker properties of tumor and lymphoid cell lines derived from a patient with squamous cell carcinoma.

A squamous cell carcinoma tumor cell line, COLO 227, derived from a metastatic tumor in a Caucasian male, produces both parathyroid hormone and carcinoembryonic antigen. A chromosome mode of 106 predominated and the X and Y chromosomes were retained. Seven marker chromosomes were identified. Cytogenetic analysis revealed an isochromosome 8 marker similar to a HeLa cell line marker and an isochromosome 17 marker described in other cancers. An autochthonous lymphoid cell line, COLO 219, was established and characterized. COLO 219 is a normal lymphoid cell line with B-cell characteristics. This autochthonous system of both cultured tumor cells and cultured lymphocytes is of use in immunological studies.

B-Lymphocytes↗