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21.
Aneuploidy induction by water extract from Tripterygium hypoglaucum (Level) Hutch in mouse bone marrow cells 总被引:2,自引:1,他引:2
Hie aneuploidy-inducing activity of a Chinese medicinal herb,Tripterygium hypoglaucum (level) Hutch (THH), was investigatedby means of three cytogenetic end-points, i.e. C-mitotic (CM)effects, micronuclei (MN) and parallel chromosome structuralaberration (CA) analyses in vivo. The CA analysis was expectedto reflect the origins of MN induced by clastogens or aneugens.The experiments were performed on mouse bone marrow cells. Theanimals were treated with the crude water extracts of THH (singlei.p. injection) in the dose range 120686 mg/kg. Colchicine(COL) was taken as a positive control for its known aneuploidy-inducingeffects. THH showed similar genotoxic effects to COL in CM,MN and CA analyses: positive CM effects were observed accompaniedwith increases of mitotic index and frequencies of CM cellsas well as decreased frequencies of anaphase in all of the THH-treatedgroups. The compound showed a positive MN response in bone marrowpolychromatic erythrocytes but was negative in CA analyses.No sex differences were found in any treated group. The preliminaryresults suggested that THH is an aneuploidy inducer in mousebone marrow cells under the present experimental conditions. 相似文献
22.
Kermit Zhang Eleina Cox Samuel Strom Zhuo Luan Xu Alexis Disilvestro Kelly Usrey 《American journal of medical genetics. Part A》2020,182(9):2124-2128
Baraitser‐Winter cerebrofrontofacial syndrome (BWCFF) is a rare autosomal dominant developmental disorder associated with missense mutations in the genes ACTB or ACTG1. The classic presentation of BWCFF is discerned by the combination of unique craniofacial characteristics including ocular coloboma, intellectual disability, and hypertelorism. Congenital contractures and organ malformations are often present, including structural defects in the brain, heart, renal, and musculoskeletal system. However, there is limited documentation regarding its prenatal presentation that may encourage healthcare providers to be aware of this disorder when presented throughout pregnancy. Herein we describe a case of a pregnancy with large cystic hygroma and omphalocele. Whole exome sequencing (WES) was performed and a de novo, heterozygous, likely pathogenic mutation in ACTB was detected, c.1004G>A (p.Arg335His), conferring a diagnosis of BWCFF. 相似文献
23.
为探讨烧伤对大鼠免疫功能的影响及不同免疫调节剂对它的作用,本研究利用烫伤大鼠实验模型,采用溶血分光光度法和微量细胞病变抑制法,在整体条件下分别测定了各组烫伤大鼠伤后第5、10天时脾细胞产生TFN-γ和抗SRTBC抗体的能力。 相似文献
24.
Yin C Ying L Zhang PC Zhuo RX Kang ET Leong KW Mao HQ 《Journal of biomedical materials research. Part A》2003,67(4):1093-1104
Galactosylated surface is an attractive substrate for hepatocyte culture because of the specific interaction between the galactose ligand and the asialoglycoprotein receptor on hepatocytes. In this study, we described a scheme to achieve high density of immobilized galactose ligands on polyethylene terephthalate (PET) surface by first surface-grafting polyacrylic acid on plasma-pretreated PET film under UV irradiation, followed by conjugation of a galactose derivative (1-O-(6'-aminohexyl)-D-galactopyranoside) to the grafted polyacrylic acid chains. A high galactose density of 513 nmol/cm(2) on the PET surface was used in this study to investigate the behavior of cultured hepatocyte. This engineered substrate showed high affinity to fluorescein isothiocyanate-lectin binding. Primary rat hepatocytes, when seeded at a density of 2 x 10(5) cells/cm(2), attached to the galactosylated PET substrate at a similar efficiency compared with collagen-coated substrate. The hepatocytes spontaneously formed aggregates 1 day after cell seeding and showed better maintenance of albumin secretion and urea synthesis functions than those cultured on collagen-coated surface. 相似文献
25.
羟基磷灰石/胶原-聚乳酸三维多孔框架材料的制备成形及分析 总被引:2,自引:2,他引:2
目的:合成新型的复合生物材料框架作为骨组织工程研究的细胞外基质材料。方法:本研究采用材料学自组装技术的原理,以Ⅰ型胶原蛋白为分子模板,引导钙磷盐在液相中的矿化,制备具有天然骨基质层状结构的羟基磷灰石/胶原复合材料,并以热致分相法制备了羟基磷灰石/胶原-聚乳酸复合三维多孔框架。结果:羟基磷灰石/胶原复合材料具有与天然骨基质相似的成分与结构,加入聚乳酸制备成三维多孔框架,孔隙直径界于50um-300um。结论:羟基磷灰石/胶原-聚乳酸复合三维多孔框架可能作为骨组织工程良好的细胞外基质材料。 相似文献
26.
The specific recognition between asialoglycoprotein receptor and galactose ligand at cell-substrate interfaces has been shown to mediate hepatocyte adhesion and maintain liver specific functions of hepatocytes. Conventionally, the success of hepatocyte attachment on engineered tissue scaffold is inferred from the degree of two-dimensional cell spreading that is measured by transmitted light microscopy. However, the actual contact mechanics and adhesion strength of hepatocytes during two-dimensional cell spreading has not been elucidated due to lack of biophysical probe. In this study, a novel biophysical technique known as confocal reflectance interference contrast microscopy (C-RICM) in conjunction with phase contrast microscopy is utilized to probe the adhesion dynamics, contact mechanics and two-dimensional spreading kinetics of HepG2 cells on galactose immobilized and collagen gel coated substrates. C-RICM demonstrates that HepG2 cells form strong adhesion contacts with both galactose-immobilized surfaces and collagen gel coated substrates. Moreover, HepG2 cells maintain their compact shapes in the presence of asialoglycoprotein receptor-mediated recognition while they become exceedingly spread under integrin-mediated adhesion on collagen gel coated substrate. The initial rate of adhesion contact formation and the steady-state adhesion energy of HepG2 cell population are highest on substrate conjugated with galactose ligand via a longer spacer. The adhesion dynamics and final adhesion energy of HepG2 cells depends both on the type of ligand-receptor interaction and the length of spacer between the ligand and substrate. Most importantly, new biophysical insights into the initial hepatocyte attachment that are critical for hepatocyte culture are provided through the decomposition of two-dimensional spreading and adhesion contact formation on bio-functional substrates. 相似文献
27.
28.
PKA对跨膜型和分泌TNF—α胞毒效应的影响 总被引:4,自引:1,他引:4
目的:研究PKA对跨膜型TNFα(mTNF-α)杀瘤效应的影响。方法:用TNF生物活性检测方法在体外观察PKA激活剂和抑制剂对一型TNF-α杀伤不同肿瘤细胞的影响。结果:PKA激活剂Forskolin(10μmol/L)和抑制剂H8(15μmol/L)可分别增强和抑制sTNF-α对其第三靶细胞的胞毒活性,对其余4株耐受细胞却无逆转使用,而且对mTNF-α的胞毒效应无任何影响。此外,PKA活性增强, 相似文献
29.
30.
Summary: Novel temperature sensitive poly(N‐isopropylacrylamide‐co‐acryloyl beta‐cyclodextrin) (P(NIPA‐co‐A‐CD)) hydrogels with fast shrinking rates were prepared by radical polymerization of NIPA, A‐CD and crosslinker in a mixture of water/1,4‐dioxane as solvent. Because the mixed solvent was a poor solvent for the copolymers, phase separation occurred during the polymerization, which resulted in a heterogeneous, porous structure of the hydrogels. In contrast to the normal PNIPA hydrogel and the homo P(NIPA‐co‐A‐CD) gel prepared in water, the P(NIPA‐co‐A‐CD) hydrogels synthesized in water/1,4‐dioxane as solvent exhibited higher swelling ratios at the temperature below the lower critical solution temperature (LCST) and shrunk rapidly to equilibrium within shorter time when the temperature was increased above LCST. Increasing the acryloyl beta‐cyclodextrin content in the gels led to a slight decrease of the swelling ratio at lower temperature and had no marked influence on the shrinking kinetics. The gels prepared in water/1,4‐dioxane, at different v/v ratios of 1.0/0.2, 0.8/0.4 and 0.6/0.6, showed similar properties.