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111.
112.
Improved clonal and nonclonal growth of human,rat and bovine adrenocortical cells in culture 总被引:2,自引:0,他引:2
Jan M. McAllister Peter J. Hornsby 《In vitro cellular & developmental biology. Plant》1987,23(10):677-685
Summary This report describes the development of a culture system for long-term growth and cloning of human fetal adrenocortical cells.
Optimal conditions for stimulating clonal growth were determned by testing the efficacy of horse serum (HS), fetal bovine
serum (FBS), fibroblast growth factor (FGF), epidermal growth factor (EGF), fibronectin, and a combination of growth factors,
UltroSer G, in stimulating growth from low density. Optimal conditions for clonal growth were achieved using fibronectin-coated
dishes and DME/F12 medium with 10% FEBS, 10% HS, 2% UltroSer G, and 100 ng/ml FGF or 100 pM EGF. Conditions for growth at clonal density were found to be optimal for growth of early passage, nonclonal cultures at
higher densities. The improved growth conditions used for cloning were shown to allow continued long-term growth of nonclonal
human adrenocortical cells without fibroblasts overgrowth. All cells in cultures grown in HS, FBS, and UltroSer G had morphologic
characteristics of adrenocortical cells, whereas cells grown in FBS only rapidly became overgrown with fibroblasts. Clonal
and nonclonal early passage human adrenocortical cells had smilar mitogenic responses to FGF and EGF. Whereas FGF, EGF, and
UltroSer G showed similar stimulation of DNA synthesis and clonal growth in human adrenocortical cells and human adrenal gland
fibroblasts, the tumor promoter 12-O-teradecanoylphorbol-13-acetate stimulated growth only in adrenocortical cells and was strongly inhibitory to growth in fibroblasts.
In both cell types, forskolin inhibited DNA synthesis. Human adrenocortical cell cultures were functional and synthesized
cortisol, dehydroepiandrosterone, and dehydroepiandrosterone sulfate. The improved growth conditions for clonal growth of
human adrenocortial cells also provided optimal conditions for long-term growth of cultured rat adrenocortical cells and ncreased
the cloning efficiency of cultured bovine adrenocortical cells.
This work was supported by Research grants AG-00936 and AG-06108 from the National Institute on Aging, Bethesda, MD. 相似文献
113.
114.
The influence of feeding on the bioavailability of oxytetracycline was studied in preruminant calves. Oxytetracycline was given in water as a drench to fasting calves or was mixed in the milk replacer. Compared to water the bioavailability was significantly reduced (53.5%) when oxytetracycline was mixed in the milk re-placer. A further reduction, 83.3 %, occurred when the calves were treated one hour post milk feeding. Also concentrate was found to reduce the bioavailability. Very high serum levels were recorded when the drug was given in an oral rehydration solution, pH 4.9, containing glycine. The values obtained when an alkaline (pH 8.3) solution without glycine was used did not differ from the levels recorded when oxytetracycline was given in water. It was suggested that the use of oxytetra-cyclines in feeds may be questioned because of their well-known complex forming ability. 相似文献
115.
Chris L. Schürmann Jan A. R. A. M. van Hooff 《International journal of primatology》1986,7(3):265-287
Recent field data indicate that MacKinnon’s model of the orang-utan’s sexual and agonistic activity needs to be revised. In
this model, male reproductive activity is concentrated in an extended phase of subadulthood and in early adulthood. According
to this model, the role of older adult males is primarily that of range guardian, and in that role they would ensure that
the offspring they had generated earlier would have safe access to food resources. This study presents cases suggesting that
subadult males, even though sexually active, may have low reproductive success. In previous studies adult males were shown
to display less sexual initiative than subadult males. In this study an adult male was at times involved infrequent mating
activity in response to proceptive activity of females in the course of consortship. This adult male proved to be a successful
breeder, thus refuting the hypothesis of adult male sterility. The female is most likely to conceive through cooperative mating
in lengthy consortships with the dominant resident adult male. We hypothesize that the extended subadult phase represents
a submissive strategy, allowing subadult males to remain in the home range of adult males but with minimal reproductive success. 相似文献
116.
Dr. Jacques F. G. M. Meis P. Jos M. Rijntjes Jan Peter Verhave Thivi Ponnudurai Michael R. Hollingdale Judith E. Smith Robert E. Sinden Paul H. K. Jap Joseph H. E. T H Meuwissen Sing Hiem Yap 《Cell and tissue research》1986,244(2):345-350
Summary Recent advances in the ability to culture the hepatic forms of mammalian malaria parasites, particularly of the important human pathogen Plasmodium falciparum have provided novel opportunities to study the ultrastrucural organisation of the parasite in its natural host cell the human hepatocyte. In this electron-microscopic and immunofluorescence study we have found the morphology of both parasite and host cell to be well preserved. The exoerythrocytic forms, which may be found at densities of up to 100/cm2, grow at rates comparable to that in vivo in the chimpanzee. In the multiplying 5- and 7-day schizogonic forms the ultrastructural organisation of the parasite bears striking resemblances to other mammalian parasites, e.g., the secretory activity and distribution of the peripheral vacuole system, but also homology with avian parasites, e.g., in nuclear and nucleolar structure and mitochondrial form. The latter homologies support earlier suggestions of the close phylogenetic relationship of P. falciparum with the avian parasites. Evidence is also presented showing the persistence of the cytoskeleton of the invasive sporozoite within the cytoplasm of the ensuing rapidly growing vegetative parasites. 相似文献
117.
Yolande A. Holthuijzen Jan F. L. van Breemen J. Gijs Kuenen Wil N. Konings 《Archives of microbiology》1986,144(4):398-404
For purifying carboxysomes of Thiobacillus neapolitanus an isolation procedure was developed which resulted in carboxysomes free from whole cells, protoplasts and cell fragments. These purified carboxysomes are composed of 8 proteins and at the most of 13 polypeptides. The two most abundant proteins which make up more than 60% of the carboxysomes, are ribulose-1,5-bisphosphate carboxylase and a glycoprotein with a molecular weight of 54,000. The shell of the carboxysomes consists of four glycoproteins, one also with a molecular weight of 54,000. The other proteins are present in minor quantities. Ribulose-1,5-bisphosphate carboxylase is the only enzyme which could be detected in the carboxysomes and 3-phosphoglycerate was the only product formed during incubation with ribulose-1,5-diphosphate and bicarbonate. The supernatant of a broken and centrifuged carboxysome suspension contained the large subunit of ribulose-1,5-bisphosphate carboxylase. The small subunit of ribulose-1,5-bisphosphate carboxylase was found in the pellet together with the shell proteins which indicates that the small subunit of ribulose-1,5-bisphosphate carboxylase is connected to the shell.Abbreviations RuBisCO
ribulose-1,5-bisphosphate carboxylase
- PMSF
phenylmethylsulfonyl fluoride
- PAA
gelectrophoresis, polyacrylamide gelelectrophoresis
- SDS
sodium dodecyl sulphate
- CIE
crossed immunoelectrophoresis
- IEF
isoelectric focusing 相似文献
118.
Jan Lindgren Magdalena Blaszczyk Barbara Atkinson Zenon Steplewski Hilary Koprowski 《Cancer immunology, immunotherapy : CII》1986,22(1):1-7
Summary Over 600 hybridomas were derived from the immunization of mice with live cells and aqueous extracts of the human prostatic carcinoma cell line PC3. A total of 26 hybridomas with restricted reactivities were selected, subcloned and antibodies tested on a variety of tumor and normal cells. Seven monoclonal antibodies showed reactivity for prostate cancer and other tumor cell lines, including breast carcinomas. Three of the antibodies obtained after immunization with live cells reacted with live cells only and three of the four antibodies obtained after immunization with cell extract reacted with cell extracts and spent culture media. The fourth antibody in the latter group was reactive only in the immunoperoxidase staining assay. Antibody PrS5 recognized a 90,000 molecular weight molecule from 125I-surface-labeled cells in immunoprecipitation analysis. Antibodies PrE3 and PrD8 detected a nonacid glycolipid pentasaccharide from PC3 cells and meconium, and a glycoprotein of 115,000 molecular weight from 125I-surface-labeled red blood cells. The similar patterns of reactivity in RIAs and antigen analysis suggest that antibodies PrE3 and PrD8 recognize the same molecule. The results emphasize the usefulness of immunohistochemistry in the testing of monoclonal antibodies and the impact of the form in which the antigen is presented on the resultant antibody specificity 相似文献
119.
Genes for human U4 small nuclear RNA 总被引:10,自引:0,他引:10
120.
The bulk rheology of close-packed red blood cells in shear flow 总被引:1,自引:0,他引:1
A theoretical analysis is made of the dynamical behavior and bulk rheology of close-packed red blood cell suspensions subjected to simple shear flow. The model for the polyhedral cell shapes and tank-treading membrane motion developed in the companion paper (1) is used. The flow in the thin lubricating plasma layers between cells is analyzed taking into account the mechanical properties of the membrane at the corner regions of sharp membrane curvature. This leads to predictions for the apparent viscosity as a function of hematocrit and shear rate. Good agreement with experimental results is obtained at moderate and high shear rates (above 20 s-1). At lower shear rates, a rapid rise in apparent viscosity has been found experimentally, and the mechanisms leading to this behavior are examined. 相似文献