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51.
Masamitsu Honma Eiko Kataoka Kiyokata Ohnishi Tadao Ohno Masao Takeuchi Nobuo Nomura Hiroshi Mizusawa 《In vitro cellular & developmental biology. Animal》1992,28(1):24-28
Summary Using the polymorphic DNA probes, ChdTC-15, ChdTC-114, pYNH24, and λTM-18, a DNA profiling system was developed that verified
identities of individual cultured cell lines collected in the Japanese cell banks, JCRB, RCB, and IFO. These highly polymorphic
DNA probes include both VNTR (Variable Number of Tandem Repeats) sequences and substantial lengths of unique regions. In the
mixed probe system, several distinct bands from four to eight can be used for cell line identification. These bands were widely
spread in a range of molecular sizes, and were stable and reproducible under stringent conditions of Southern blot hybridization.
Because the DNA profile was specific for each individual human cell line, it is useful not only to authenticate many existing
cultured cell lines but also to monitor their identity during propagation in a laboratory, and to confirm newly established
lines as unique. 相似文献
52.
Morphologic differentiation of colon carcinoma cell lines HT-29 and HT-29KM in rotating-wall vessels
Thomas J. Goodwin J. Milburn Jessup David A. Wolf 《In vitro cellular & developmental biology. Animal》1992,28(1):47-60
Summary A new low shear stress microcarrier culture system has been developed at NASA’s Johnson Space Center that permits three-dimensional
tissue culture. Two established human colon adenocarcinoma cell lines, HT-29, an undifferentiated, and HT-29KM, a stable,
moderately differentiated subline of HT-29, were grown in new tissue culture bioreactors called Rotating-Wall Vessels (RWVs).
RWVs are used in conjunction with multicellular cocultivation to develop a unique in vitro tissue modeling system. Cells were
cultivated on Cytodex-3 microcarrier beads, with and without mixed normal human colonic fibroblasts, which served as the mesenchymal
layer. Culture of the tumor lines in the absence of fibroblasts produced spheroidlike growth and minimal differentiation.
In contrast, when tumor lines were co-cultivated with normal colonic fibroblasts, initial growth was confined to the fibroblast
population until the microcarriers were covered. The tumor cells then commenced proliferation at an accelerated rate, organizing
themselves into three-dimensional tissue masses that achieved 1.0- to 1.5-cm diameters. The masses displayed glandular structures,
apical and internal glandular microvilli, tight intercellular junctions, desmosomes, cellular polarity, sinusoid development,
internalized mucin, and structural organization akin to normal colon crypt development. Differentiated samples were subjected
to transmission and scanning electron microscopy and histologic analysis, revealing embryoniclike mesenchymal cells lining
the areas around the growth matrices. Necrosis was minimal throughout the tissue masses. These data suggest that the RWV affords
a new model for investigation and isolation of growth, regulatory, and structural processes within neoplastic and normal tissue. 相似文献
53.
Paola Villa 《Evolutionary anthropology》1992,1(3):93-104
The key argument for the identification of prehistoric cannibalism is provided by analysis of close similarities in the treatment of human and animal remains. Such analysis requires precise data on depositional context, meticulous excavation records, detailed bone modification studies, a relatively large sample of human and animal postcranial bones, and data on local mortuary practices. With the exception of Fontbrégoua Cave, these necessary conditions are lacking at all Stone Age European sites where it has been hypothesized that cannibalism occurred. The alternative hypothesis of secondary burial practices has been proposed informally for some sites and, in a more formal and detailed way, for Krapina and Fontbrégoua. However, this hypothesis does not have a higher probability, is not justified by current data, and uses ethnographic analogies to prop up interpretations of materials for which contextual data are missing or have been neglected. At Fontbrégoua, cannibalism remains the simplest and most plausible explanation of the evidence; at Krapina and other sites the available evidence is insufficient to prove either secondary burial or cannibalism. 相似文献
54.
55.
Bombesin production by human small cell carcinoma of the lung 总被引:5,自引:0,他引:5
G D Sorenson S R Bloom M A Ghatei S A Del Prete C C Cate O S Pettengill 《Regulatory peptides》1982,4(2):59-66
A series of continuous cell lines of human small cell carcinoma of the lung (SCCL) have been evaluated for the production of bombesin (BN). In early established cultures BN was detected in the medium of 9 out of 11 cell lines and in 6 out of 7 cell homogenates examined. Levels in the medium were frequently higher in cultures of later passages compared to earlier passages of the same line and low levels developed in the two previously negative cell lines. Plasma concentrations were greater than 80 pmol/l in 2 out of 27 (7%) randomly selected patients with SCCL. A culture (DMS 406) established from the tumor of a patient with the highest plasma level (1240 pmol/l) was the highest producer in vitro. The results indicate that BN, which has been demonstrated immunocytochemically to be present in normal bronchial mucosal cells, is frequently produced by SCCL in vitro but elevated plasma levels are infrequently found in patients with this neoplasm. 相似文献
56.
The locus for sorbitol dehydrogenase (SORD, E.C. 1.1.1.14) has been shown to segregate with hexosaminidase A and mannose phosphate isomerase in a series of human-Chinese hamster somatic cell hybrids. Cytogenetic analysis supports the assignment to chromosome 15 and further defines the gene locus to the region 15pterq21.This research was supported by the Medical Research Council of Canada (MT 4061), the Children's Hospital of Winnipeg Research Foundation, Inc., and the Department of Health, Province of Manitoba (H.S.W.). 相似文献
57.
We have examined the effect of addition of hydroxocobalamin to growth medium on the activity of the adenosylcobalamin-requiring enzyme methylmalonyl CoA mutase in normal human fibroblasts and in mutant human fibroblasts derived from patients with inherited methylmalonicacidemia. The mutant cell lines were assigned to four distinct genetic complementation groups (cbl A, cbl B, cbl C, and cbl D), each deficient in some step in the synthesis of adenosylcobalamin from hydroxocobalamin. After control cells were grown in cobalamin-supplemented medium, mutase holoenzyme activity increased markedly in a time- and concentration-dependent fashion. Growth in cobalamin-supplemented medium had no effect on mutase activity in some mutant lines belonging to the cbl B group, while activity increased severalfold in other cbl B mutants and in all cbl A, cbl C, and cbl D mutants examined, although mutase activity was still <10% of control. Comparison of mutase holoenzyme activity and total propionate pathway activity suggests that enhancement of mutase activity in mutant cells after cobalamin supplementation to values 5–10% of control may be sufficient to overcome the inherited metabolic block and to restore total pathway activity to normal.This work was supported in part by a research grant from the National Institutes of Health (AM 12579). H. F. W. is a recipient of a traineeship from the National Institutes of Health (T01-GM02299). 相似文献
58.
Abla A. Creasey Helene S. Smith Adeline J. Hackett Kimie Fukuyama William L. Epstein Stewart H. Madin 《In vitro cellular & developmental biology. Plant》1979,15(5):342-350
Summary Three human melanoma cell lines derived from one primary and two metastatic tumors from three different patients were characterized
for growth properties usually associated with malignant transformation; these include cell morphology, growth rate, saturation
density, growth in semisolid media, colony-forming ability on contact-inhibited monolayers of normal fibroblasts and epithelial
cells, and tumorigenicity in immunosuppressed mice. Variations in expression of aberrant properties were evident among the
lines. One of the metastatic lines satisfied all the parameters of malignancy tested and the other showed a number of these
properties, whereas the primary essentially fulfilled only one. These results suggest that cultured melanoma cells reflect
the clinical variability often observed among melanoma patients and the metastatic melanoma seems to display a higher degree
of malignant transformation than the primary.
THis work was supported in part by USPHS Grant No. 5 T01 AI00332-06 from the National Institutes of Health, Contract E73-2001-N01-CP-3-3237
from the Virus Cancer Program of the National Cancer Institute, and USPHS Grant No. 0H00714-02 from the National Institute
for Occupational Safety and Health. 相似文献
59.
Lucy A. Barrett Wolfgang J. Mergner Benjamin F. Trump 《In vitro cellular & developmental biology. Plant》1979,15(12):957-966
Summary Segments of human thoracic aorta were maintained in long-term explant culture for 18 weeks in serum-supplemented medium. The
aortas were grossly normal in appearance, and random samples fixed for light microscopy prior to culture revealed a normal
morphology. The intima contained no more than five layers of smooth muscle cells. After 7 days in culture, the intima was
noticeably thicker than the uncultured segments. The increased thickness was due to proliferating smooth muscle cells and
production of extracellular material. After several months in culture, extracellular material consisting of collagen and flocculent
material was present in areas resembling atherosclerotic fibrous plaques. A peripheral growth, which formed around the explant,
was composed of fibroblastlike cells and added to the overall thickness of the intima. However, aortic segment maintained
for up to 2 months in serum-free culture medium showed no cellular proliferation. This study demonstrates that changes resembling
early stages of atherosclerosis occur in human aortas maintained in explant culture using routine culture procedures.
Supported in part by the Pangborn Fund and the Graduate School of the University of Maryland.
This is publication 443 from the Cellular Pathobiology Laboratory. 相似文献
60.
J M Saez F Haour A M Cathiard 《Biochemical and biophysical research communications》1978,81(2):552-558
The early mechanism of hCG induced down regulation of its own receptor as well as steroidogenesis refractoriness of rat Leydig cells to gonadotropin stimulation have been investigated. A single injection of 5, 12, 25, 50 and 100 IU of hCG in rats induced within 8 hours, Leydig cells desensitization. However, apparent receptor loss was significantly lower only in the rats who received 50 and 100 IU of hCG. Cycloheximide inhibits hCG-induced receptors loss but had no effect on hCG-induced desensitization. The most likely explanation for desensitization in the presence of binding sites and a normal adenylate cyclase, is a defective coupling between the receptor sites and the catalytic subunit. 相似文献