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51.
In peripheral blood mononuclear cells (PBMC), matrix metalloproteinase (MMP)-9 mediates the extravasation of immune cells and may be involved in tissue destruction during inflammation. We investigated the effect of the pro-inflammatory cytokines interleukin (IL-)12 and 15 on the secretion of MMP-9 in PBMC. IL-15, but not IL-12, induces MMP-9 in PBMC and in T cells. Moreover, the combination of IL-15 and IL-2 had an additive effect. In contrast, both IL-12 and IL-15 induced the release of tissue inhibitor of metalloproteinases (TIMP)-1. IL-15 led to a dose-dependent increase of the MMP-9/TIMP-1 ratio as a measure for increased proteolytic capacity. We conclude that IL-15 mediates its effects in inflammation in part through MMP-9. 相似文献
52.
Isoelectric focusing of superoxide dismutase: report of the unique SOD A*2 allele in a US white population 总被引:1,自引:0,他引:1
An isoelectric focusing procedure in an ultranarrow pH range (5.0-5.5) polyacrylamide gel is described for the determination of superoxide dismutase (SOD) phenotypes. The occurrence of the rare SOD A*2 allele in the Caucasian population of Utah is also reported at a polymorphic frequency (0.011). The presence of the SOD A 2 unique allele in the Mormons of Utah is compatible with their historical affinity with Scandinavians. 相似文献
53.
G. Mark Lathrop Peter O''Connell Mark Leppert Yusuke Nakamura Martin Farrall Lap-Chee Tsui Jean-Marc Lalouel Ray White 《Genomics》1989,5(4):866-873
We have constructed a primary genetic linkage map from DNA markers that define 25 loci on chromosome 7. The markers form a continuous linkage group of 141 cM in males and 340 cM in females; female genetic distances were on average more than twofold higher than those in males throughout the chromosome. The average heterozygosity of the loci was 45%. A subset of the markers can be used for efficient application of this map to studies of human genetic disease. 相似文献
54.
P O'Connell G M Lathrop Y Nakamura M L Leppert R H Ardinger J L Murray J M Lalouel R White 《Genomics》1989,4(1):12-20
We have used a combination of 30 serological, protein electromorphic, and DNA markers defining 28 loci to construct a linkage map of chromosome 1. These markers form a continuous linkage group of 320 cM in males and 608 cM in females; female genetic distances were on average twofold higher than those of males across the map. Among the DNA markers are 10 highly polymorphic markers reflecting loci that contain a variable number of tandem repeats, well distributed over the length of the chromosome, that will be highly efficient anchor points for application of this map to studies of human genetic disease. 相似文献
55.
Summary In the course of a systematic study of cytogenetics, morphology, and clinical follow-up of hydatidiform moles we encountered two unusual cases of partial hydatidiform moles each with a 92,XXXY karyotype. Previously reported cases of tetraploidy, of 92,XXXX or 92,XXXY karyotype, resulted from a failure of the first mitotic division of a normal zygote. This is to our knowledge the first report of tetraploidy with XXXY sex chromosomes. Study of chromosomal heteromorphisms, isozymes, and restriction fragment length polymorphisms reveal that both present cases resulted from a combination of a haploid ovum with three haploid sets of paternal chromosomes either by the mechanism of trispermy (involving three separate haploid spermatozoa) or through dispermy (involving one haploid and one diploid sperm). Both cases resembled closely partial moles in their morphology; one gave a highly typical clinical picture while the other was recognized at an early voluntary abortion. Partial moles are ordinarily triploids of nearly always diandric constitution that evince focal villous swelling with cistern formation and focal trophoblastic hyperplasia. The findings here presented point to an association of molar phenotype with an excess of paternal over maternal haploid sets. 相似文献
56.
A cultured rat ovarian cell line (31 A-F(2)) was used to study the effect of growth factors (epidermal growth factor [EGF] and fibroblast growth factor [FGF]), a survival factor (ovarian growth factor [OGF]), a hormone (insulin), and an iron-binding protein (transferring) on cell proliferation and steroid production under defined culture conditions. EGF and insulin were shown to be mitogenic (half-maximal response at 0.12 nM and 0.11 muM, respectively) for 31A-F(2) cells incubated in serum-free medium. EGF induced up to three doublings in the cell population, whereas insulin induced an average of one cell population doubling. FGF, OGF, and transferrin were found not to have any prominent effect on cell division when incubated individually with 31A-F(2) cells in serum-free medium. However, a combination of EGF, OGF, insulin, and transferrin stimulated cell division to the same approximate extent as cells incubated in the presence of 5 percent fetal calf serum. EGF or insulin did not significantly affect total cell cholesterol levels (relative to cells incubated in serum-free medium) when incubated individually with 31A-F(2) cells. However, cell cholesterol levels were increased by the addition of OGF (250 percent), FGF (370 percent), or a combination of insulin and EGF (320 percent). Progesterone secretion from 31A-F(2) cells was enhanced by EGF (25 percent), FGF (80 percent), and insulin (115 percent). However, the addition of a mitogenic mixture of EGF, OGF, insulin, and transferrin suppressed progesterone secretion 150 percent) below that of control cultures. These studies have permitted us to determine that EGF and insulin are mitogenic factors that are required for the growth of 31A-F(2) cells and that OGF and transferrin are positive cofactors that enhance growth. Also, additional data suggest that cholesterol and progesterone production in 31A-F(2) cells can be regulated by peptide growth factors and the hormone insulin. 相似文献
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