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1.
Hanna Gladh Erika Bergsten Folestad Lars Muhl Monika Ehnman Philip Tannenberg Anna-Lisa Lawrence Christer Betsholtz Ulf Eriksson 《PloS one》2016,11(3)
Platelet-derived growth factor D (PDGF-D) is the most recently discovered member of the PDGF family. PDGF-D signals through PDGF receptor β, but its biological role remains largely unknown. In contrast to other members of the PDGF family of growth factors, which have been extensively investigated using different knockout approaches in mice, PDGF-D has until now not been characterized by gene inactivation in mice. Here, we present the phenotype of a constitutive Pdgfd knockout mouse model (Pdgfd-/-), carrying a LacZ reporter used to visualize Pdgfd promoter activity. Inactivation of the Pdgfd gene resulted in a mild phenotype in C57BL/6 mice, and the offspring was viable, fertile and generally in good health. We show that Pdgfd reporter gene activity was consistently localized to vascular structures in both postnatal and adult tissues. The expression was predominantly arterial, often localizing to vascular bifurcations. Endothelial cells appeared to be the dominating source for Pdgfd, but reporter gene activity was occasionally also found in subpopulations of mural cells. Tissue-specific analyses of vascular structures revealed that NG2-expressing pericytes of the cardiac vasculature were disorganized in Pdgfd-/- mice. Furthermore, Pdgfd-/- mice also had a slightly elevated blood pressure. In summary, the vascular expression pattern together with morphological changes in NG2-expressing cells, and the increase in blood pressure, support a function for PDGF-D in regulating systemic arterial blood pressure, and suggests a role in maintaining vascular homeostasis. 相似文献
2.
A 3-h exposure of V79 Chinese hamster cells with the sensory irritant 2-chlorobenzylidene malonitrile (CS) caused apolar mitoses in a dose-dependent manner. With a preparation and staining technique that allows for the visualization of the spindle apparatus and the chromosomes it was found that unlike in Colcemid-induced c-metaphases residual spindle fibers or microtubule material were present in the majority of CS-induced c-metaphases. The observation suggests different mechanisms for the induction of the c-mitotic effect by the two spindle poisons. 相似文献
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The study was composed of 27 persons that displayed vague symptoms similar to those of the victims of Minamata and Iraq. Skew
distributions of mercury were observed in individual erythrocytes and neutrophil granulocytes when measured by PIXE. Mercury
could not be detected in the platelets. The erythrocytes also displayed lowered concentrations of magnesium and zinc, together
with increased concentrations of calcium and strontium. The neutrophils displayed decreased concentrations of magnesium and
zinc and increased concentrations of calcium, strontium, and iron. The presence of mercury and the altered elemental profiles
in the erythrocytes and the neutrophil granulocytes are suggested as early signs of exposure. 相似文献
6.
Summary In order to establish a transformation system for P. chrysogenum autonomously replicating vectors were constructed using mitochondrial DNA sequences from the fungus. A physical map of the mt DNA of a production strain was established using ten different restriction enzymes. Unexpectedly, the mt DNA of this strain proved to be significantly smaller than that of a second strain from a culture collection (27 kb versus 49 kb). Various fragments representing about 71% of the 27 kb mt DNA were cloned and, at first, preselected for replicating activity in an intermediate host (Saccharomyces cerevisiae). Two of these fragments also promoted autonomous replication in P. chrysogenum, which was confirmed by isolation of bulk DNA and transfer into E. coli. For selection of transformants in P. chrysogenum the prokaryotic kanamycin resistance gene was used which increased about twofold the resistance against G418.
Present address: Institut für Biotechnologie, Fachgebiet Mikrobiologie, Techn. Universität Berlin, Seestr. 13, D-1000 Berlin 65 相似文献
7.
Helena Lennholm Bengt Lindberg Ulf Lindquist Frank Lindh Bo Nilsson 《Glycoconjugate journal》1987,4(4):313-316
N-Deacetylation of 2-acetamido-2-deoxy-hexose residues is accomplished in liquid ammonia containing calcium. Oligosaccharides, lacto-N-fucopentaose II and lacto-N-difucohexaose I, containing 3,4-disubstitutedN-acetylhexosamine residues are quantitativelyN-deacetylated. When applied to polysaccharides, however, only partialN-deacetylation was achieved.Author for correspondence. AXRD 相似文献
8.
Summary A rapid, sensitive, and reproducible enzyme-linked immunosorbent assay (ELISA), for the detection of the serological sex-specific (Sxs) antigen (formerly termed H-Y antigen; see Introduction), is described. This assay uses bovine lestes extract as the solid phase antigen, and high-titer anti-Sxs antisera and a urease-conjugated anti rat-IgG as the first and second antibody respectively. The urea containing substrate causes a pH shift in a positive reaction, which in turn is visualized by the use of bromocresol purple as a pH indicator. The method, and some representative applications of it, are described in detail. 相似文献
9.
Cytogenetic effects of 3,4-dichloroaniline in human lymphocytes and V79 Chinese hamster cells 总被引:2,自引:0,他引:2
3,4-Dichloroaniline (3,4-DCA), an intermediate in various chemical syntheses, has been detected as an environmental contaminant in surface waters and in the effluents from dye-manufacturing plants. Tested for clastogenicity in human lymphocytes in vitro the compound was inactive in the chromosome aberration assay yet exhibited a positive sister-chromatid exchange response in the presence of a mammalian metabolic activation system. Exposure of V79 Chinese hamster cells to 3,4-DCA caused a concentration-dependent increase in the incidence of spindle disturbances, predominantly of the initial c-mitotic type. The results indicate that 3,4-DCA might induce aneuploidy in mammalian cells by interaction with the mitotic apparatus. 相似文献
10.
Ulf Molau 《Nordic Journal of Botany》1988,8(2):193-195
Hedbergia is described as a new, monotypic genus in the Scrophulariaceae, subfamily Rhinanthoideae, tribe Rhinantheae. The species H. abyssinica is transferred from Bartsia. Hedbergia abyssinica is the most primitive taxon so far known in the subtribe Euphrasineae. 相似文献