301
|
Abstract
The disease xeroderma pigmentosum is characterized by deficient repair of damaged DNA. Fusions of cells from different patients have defined nine genetic complementation groups (A through I), implying that DNA repair in humans involves multiple gene products. In this report, an extension of the gel electrophoresis binding assay was used to identify at least one nuclear factor that (i) bound to DNA damaged by ultraviolet radiation or the antitumor drug cisplatin, but (ii) was notably absent in cells from complementation group E. Therefore, the factor appears to participate in a versatile DNA repair pathway at the stage of binding and recognition.
Collapse
|
302
|
Chang E, Perlman AJ. Angiotensinogen mRNA. Regulation by cell cycle and growth factors. J Biol Chem 1988; 263:5480-4. [PMID: 3281943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The components of the renin-angiotensin system have been colocalized in many tissues suggesting that local generation of angiotensin II can regulate blood flow in specific organs or tissues. This in combination with the fact that proliferating tissues require angiogenesis and increased blood flow to develop have led us to study the relationship of angiotensinogen mRNA production to cell cycle regulation. Reuber H35 (H4IIE) cells were growth-arrested by serum deprivation. Cells were then treated with 10% fetal calf serum, depleted serum, or insulin. Insulin and serum were equally potent at increasing beta-actin mRNA levels, depressing angiotensinogen mRNA levels, and in increasing [3H]methyl thymidine incorporation. The half-maximal insulin effect occurred at 5 x 10(-9) M. Insulin-like growth factor I and II had no effect on any of the parameters measured. 12-O-tetradecanoyl phorbol 13-acetate (TPA) also induced beta-actin mRNA, decreased angiotensinogen mRNA, and caused an increase in [3H]methyl thymidine incorporation. The TPA effects were of shorter duration and of lower magnitude than those caused by insulin or serum. Inactivation of protein kinase C by preincubation with TPA did not block the insulin response. TPA has been shown to induce angiogenesis in vitro. Thus, these studies suggest that inhibition of angiotensinogen gene activity may be part of the proliferative or angiogenic process. Our experimental data may provide a model for further experimental dissection of the biochemical steps involved in angiogenesis.
Collapse
|
303
|
|
304
|
|
305
|
Black RJ, Yu ZP, Brown D, Chang E. Modulation of oncogene expression by epidermal growth factor and gamma-interferon in A431 squamous carcinoma cells. J BIOL REG HOMEOS AG 1988; 2:35-44. [PMID: 3140602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Epidermal growth factor (EGF) acts, in a dose dependent manner, as both a mitogen and an inhibitor of growth of the A431 squamous carcinoma cell line. gamma-interferon (IFN) also inhibits A431 cell growth. The dual effects of EGF on A431 growth and expression of the oncogenes, EGF receptor (EGFR) and Ha-ras, were evaluated with or without gamma-IFN. A mitogenic level (10pM) of EGF had no effect on expression of EGFR 10 kb mRNA or protein. gamma-IFN combined with 10pM EGF caused an initial drop in EGFR mRNA not reflected at the protein level; at 72 hours, the level of EGFR 10kb mRNA rose and inhibition of cell growth was observed. Treatment with a cytostatic amount (10nM) of EGF resulted in decreased expression of EGFR 10kb mRNA and protein within 24 hours; combined treatment with gamma-IFN caused rapid cell death. Expression of Ha-ras mRNA paralleled that of EGFR mRNA upon treatment with 10pM EGF and/or gamma-IFN, but differed with 10nM EGF.
Collapse
|
306
|
Chang E, Perlman AJ. Multiple hormones regulate angiotensinogen messenger ribonucleic acid levels in a rat hepatoma cell line. Endocrinology 1987; 121:513-9. [PMID: 3595529 DOI: 10.1210/endo-121-2-513] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Angiotensinogen is regulated by both hormones and changes in cardiovascular and electrolyte status. We have used the Reuber H35 (H4IIE) rat hepatoma cell line to study the regulation of angiotensinogen mRNA levels by dexamethasone, aldosterone, L-T3, and 17 beta-estradiol. Using the Acc I (1097 basepairs) fragment of our angiotensinogen cDNA clone, we have studied, by Northern and slot blot analysis, the accumulation of angiotensinogen mRNA in this cell culture system. Angiotensinogen mRNA of approximately 1800 bases was identified in these cells. It was identical in size to angiotensinogen mRNA from rat liver. Cells grown in medium containing serum depleted of thyroid and steroid hormones for up to 72 h showed a progressive decrease in angiotensinogen mRNA. Dexamethasone treatment resulted in a time- and dose-dependent increase in angiotensinogen mRNA. The half-maximal response occurred at 10(-9) M dexamethasone, with a maximal response of approximately 4-fold (serum-free conditions). Aldosterone induced a dose-dependent increase in mRNA. Half-maximal levels were obtained at 5 X 10(-8) M. Competition studies using the glucocorticoid antagonist RU38486 (Roussel-UCLAF) confirmed that dexamethasone was acting through the glucocorticoid receptor and suggested that aldosterone was acting through the same receptor. L-T3 treatment caused a dose and time-dependent increase in angiotensinogen mRNA levels. The half-maximal response occurred at 5 X 10(-8) M, and the maximal response was a 2-fold increase. Combined treatment with dexamethasone and L-T3 triiodothyronine resulted in a synergistic increase in angiotensinogen mRNA levels. 17 beta-Estradiol failed to elicit a change in angiotensinogen mRNA levels consistent with the observation that these cells lack estrogen receptors. Our results indicate that hepatic angiotensinogen mRNA levels are regulated in a complex fashion by several hormones. These cells provide a useful system for studying the hormonal regulation of the angiotensinogen gene.
Collapse
|
307
|
Fox LK, Hancock DD, Weems CW, Toma W, Chang E. The effect of intramammary antibiotic therapy at calving on udder health traits. J Dairy Sci 1987; 70:1696-700. [PMID: 2444634 DOI: 10.3168/jds.s0022-0302(87)80198-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The effect of intramammary antibiotic therapy at calving on mastitis infection prevalence, linear score milk somatic cell count, and milk NAGase activity, 30 d postpartum, and on milk production, 90 to 120 d postpartum, was tested. Cows (n = 175) were split into treatment and control groups at drying off. All cows received commercial dry cow therapy. At calving, treated cows received commercial lactating cow therapy in all quarters after the first two milkings; control cows were not treated. Composite milk samples were aseptically collected from all cows at drying off, calving, and 30 d postpartum. Udder health traits: linear score milk SCC, NAGase activity, and bacterial content in milk, were determined on all samples. The first three DHI milk weights were recorded for all cows. Treatment and control cows had similar prevalences of intramammary infections during the dry and 30-d postpartum periods. Least squares means of linear score milk SCC and NAGase activities were similar at drying off and calving. Cell count scores were similar between groups; NAGase activities were higher in control cows at 30 d postpartum. Control cows tended to produce more milk postpartum. Results demonstrated no advantage of intramammary therapy at calving in improving milk production or udder health.
Collapse
|
308
|
MacLeod PM, Dolman CL, Nickel RE, Chang E, Nag S, Zonana J, Silvey K. Prenatal diagnosis of neuronal ceroid-lipofuscinoses. AMERICAN JOURNAL OF MEDICAL GENETICS 1985; 22:781-9. [PMID: 4073127 DOI: 10.1002/ajmg.1320220413] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
We report on the successful prenatal diagnosis of the late infantile "Jansky-Bielschowsky" variant of the neuronal ceroid-lipofuscinoses (NCL). The fetus was studied at 16 weeks of gestation because of an affected sib. Uncultured amniotic fluid cells were studied by conventional electron microscopic techniques. About one-third of a subpopulation of dark, elongated cells contained one or more deposits of curvilinear cytosomes bound by a single unit membrane. These findings were considered typical of the late infantile variant of NCL. After delivery at term, a skin punch biopsy and a buffy coat preparation from the baby were examined and found to have similar characteristic inclusions, which confirmed our prenatal diagnosis.
Collapse
|
309
|
Romero R, Duffy TP, Berkowitz RL, Chang E, Hobbins JC. Prolongation of a preterm pregnancy complicated by death of a single twin in utero and disseminated intravascular coagulation. Effects of treatment with heparin. N Engl J Med 1984; 310:772-4. [PMID: 6700657 DOI: 10.1056/nejm198403223101207] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
|
310
|
MacLeod PM, Dolman CL, Nickel RE, Chang E, Zonana J, Silvey K. Prenatal diagnosis of neuronal ceroid lipofuscinosis. N Engl J Med 1984; 310:595. [PMID: 6694714 DOI: 10.1056/nejm198403013100914] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
|
311
|
Wilcox DP, Chang E, Dickson KL, Johansson KR. Microbial growth associated with granular activated carbon in a pilot water treatment facility. Appl Environ Microbiol 1983; 46:406-16. [PMID: 6625567 PMCID: PMC239403 DOI: 10.1128/aem.46.2.406-416.1983] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The microbial dynamics associated with granular activated carbon (GAC) in a pilot water treatment plant were investigated over a period of 16 months. Microbial populations were monitored in the influent and effluent waters and on the GAC particles by means of total plate counts and ATP assays. Microbial populations between the influent and effluent waters of the GAC columns generally increased, indicating microbial growth. The dominant genera of microorganisms isolated from interstitial waters and GAC particles were Achromobacter, Acinetobacter, Aeromonas, Alcaligenes, Bacillus, Chromobacterium, Corynebacterium, Micrococcus, Microcyclus, Paracoccus, and Pseudomonas. Coliform bacteria were found in small numbers in the effluents from some of the GAC columns in the later months of the study. Oxidation of influent waters with ozone and maintenance of aerobic conditions on the GAC columns failed to appreciably enhance the microbial growth on GAC.
Collapse
|
312
|
Hernández H, Chang E, Chea E, Chaparro E, Matos E, Piña A, Trefogli P, Zegarra O. [Complications and processes associated with typhoid fever in children]. BOLETIN MEDICO DEL HOSPITAL INFANTIL DE MEXICO 1983; 40:262-4. [PMID: 6603229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
|
313
|
Chang E. [AFP views birth control policies, practices]. DAILY REPORT. PEOPLE'S REPUBLIC OF CHINA 1980; 1:L11. [PMID: 12279242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
|
314
|
Scolnick EM, Shih TY, Maryak J, Ellis R, Chang E, Lowy D. Guanine nucleotide binding activity of the src gene product of rat-derived murine sarcoma viruses. Ann N Y Acad Sci 1980; 354:398-409. [PMID: 6261655 DOI: 10.1111/j.1749-6632.1980.tb27981.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
315
|
Chang E. The use of distributed data bases for medical information systems. Methods Inf Med 1979; 18:71-4. [PMID: 449714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
316
|
Berkowitz SD, Chang E. Preliminary design for a comprehensive data system for drug information. DRUG INFORMATION JOURNAL 1978; 12:29-32. [PMID: 10308102 DOI: 10.1177/009286157801200109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
317
|
Dolman CL, MacLeod PM, Chang E. Fine structure of cutaneous nerves in ganglioside storage disease. J Neurol Neurosurg Psychiatry 1977; 40:588-94. [PMID: 198513 PMCID: PMC492766 DOI: 10.1136/jnnp.40.6.588] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Skin punch biopsies of six children suffering from infantile or late onset Tay-Sachs disease, juvenile Sandhoff disease, or GM gangliosidosis type I, contained axons which, when viewed with the electron microscope, were distended by large amorphous black deposits. These are nonspecific residual bodies. Their large numbers indicate severe disturbance of the nerve cell and may be part of the dying back process. The three cases with Tay-Sachs disease had also axonal zebra or complex membranous bodies which appeared to be specific. Cytoplasmic vacuolation of other cells was a feature in the patient with GM1 gangliosidosis. Biopsies of three parents were negative.
Collapse
|
318
|
Dolman CL, MacLeod PM, Chang E. Skin punch biopsies and lymphocytes in the diagnosis of lipidoses. Can J Neurol Sci 1975; 2:67-73. [PMID: 1148956 DOI: 10.1017/s0317167100019995] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Skin punch biopsies and buffy coats of white blood cells were examined electron microscopically in patients suffering from a variety of storage diseases. No specific abnormalities could be detected in Gaucher's disease and adreno-leucodystrophy. While characteristic deposits were found in cutaneous nerves in globoid and metachromatic leucodystrophy, this method was deemed inferior to sural nerve biopsy. In gangliosidoses, on the other hand, pathognomonic membranous cytoplasmic bodies were common in axons of cutaneous nerves, and in generalized gangliosidoses marked vacuolation of many other cells was prominent. Specific deposits were found in various cells in skin punch biopsies and in lymphocytes of children suffering from ceroid lipofuscinoses, and in lymphocytes of their parents. This constitutes the easiest diagnostic laboratory procedure in such cases.
Collapse
|
319
|
Chan TH, Chang E. The synthesis of alkenes from carbonyl compounds and carbanions alpha to silicon. III. A full report and a synthesis of the sex pheromone of gypsy moth. J Org Chem 1974; 39:3264-8. [PMID: 4473100 DOI: 10.1021/jo00936a020] [Citation(s) in RCA: 85] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
320
|
Chang E, Linders J. A distributed medical data base. Methods Inf Med 1974; 13:221-5. [PMID: 4437397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
321
|
Yamamoto H, Ito M, Hatanaka M, Matsubara Y, Chang E. [Treatment of thoracic empyema open treatment of empyema]. KYOBU GEKA. THE JAPANESE JOURNAL OF THORACIC SURGERY 1973; 26:56-61. [PMID: 4734493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
322
|
Dolman CL, Chang E. Visceral lesions in amaurotic familial idiocy with curvilinear bodies. ARCHIVES OF PATHOLOGY 1972; 94:425-30. [PMID: 4116925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
323
|
Abstract
Temperate bacteriophages of diverse morphology were demonstrated by electron microscopy in toxigenic cultures of Clostridium botulinum. The 41 strains examined included 23 type E and multiple representatives of all other types. Cultures induced with mitomycin-C generally gave better yields, but phages were also demonstrable in untreated cultures.A provisional grouping of toxigenic types into four categories is suggested, based mainly upon associated phage patterns. Group 1 comprises types A, B, and F (all proteolytic), many of whose cultures showed an icosahedral contractile phage; others contained a "bullrushy" phage with elongated head and long flexible tail; some strains yielded both. Group 2, types B and F (non-proteolytic), were associated with icosahedral contractile phages; the latter also had an octahedral flexible phage. Group 3, types C and D, yielded conspicuously large phages with octahedral heads and very long sheathed tails. One type C strain produced a long-tailed icosahedral phage. Type E phages constituted group 4. These were icosahedral with tails generally contracted but sometimes flexible, often accompanied by superfluous sheathed tail-like structures resembling certain bacteriocins. Although non-toxigenic "OS" mutants of types A, B, E, and F were phageless, two non-toxic type E strains yielded phages. The possible role of lysogeny in the toxigenicity of certain types of this species is likely to prove difficult to elucidate.
Collapse
|
324
|
Roopnarinesingh S, Morris D, Chang E. The underweight Jamaican parturient. THE JOURNAL OF OBSTETRICS AND GYNAECOLOGY OF THE BRITISH COMMONWEALTH 1971; 78:379-82. [PMID: 5558324 DOI: 10.1111/j.1471-0528.1971.tb00290.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
325
|
Lee KH, Chang E. Dystocia due to congenital polycystic kidneys. THE JOURNAL OF OBSTETRICS AND GYNAECOLOGY OF THE BRITISH COMMONWEALTH 1970; 77:1115-6. [PMID: 5493617 DOI: 10.1111/j.1471-0528.1970.tb03474.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
326
|
Chang E, Lee KH. Survival of baby from dystocia due to congenital sacral tumour. THE JOURNAL OF OBSTETRICS AND GYNAECOLOGY OF THE BRITISH COMMONWEALTH 1970; 77:369-70. [PMID: 5427300 DOI: 10.1111/j.1471-0528.1970.tb03535.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
327
|
Chan T, Chang E, Vinokur E. The synthesis of olefins and ketones from carbonyl compounds and carbanions alpha to silicon. Tetrahedron Lett 1970. [DOI: 10.1016/s0040-4039(01)97929-8] [Citation(s) in RCA: 65] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
328
|
Yamamoto H, Chang E, Yamashita M, Ogura S, Nagai M. [Surgical case of azygos lobe association with pulmonary tuberculosis]. KYOBU GEKA. THE JAPANESE JOURNAL OF THORACIC SURGERY 1969; 22:512-5. [PMID: 5390892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
329
|
|