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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
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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
5.
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
6.
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
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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
8.
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
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Suzanne Marcus Ann-Marie Steen Björn Andersson Bo Lambert Ulf Kristoffersson Uta Francke 《Human genetics》1992,89(4):395-400
Summary A nonsense mutation at the CpG-site in the codon for Arg(169) in the gene for hypoxanthine phosphoribosyltransferase (hprt) was identified by genomic polymerase chain reaction (PCR) and DNA sequencing in cultured fibroblasts from two brothers with Lesch Nyhan's syndrome. The recurrence of mutation at this CpG-site in several unrelated Lesch-Nyhan families suggests that deamination of 5-methylcytosine is a possible mechanism for mutagenesis. The level of hprt-mRNA in the fibroblasts of the patients was similar to that in healthy controls, whereas hprt-enzyme activity was not detectable. The mutation in this family was also identified in five female relatives and prenatally in a male fetus. Unexpectedly, results from hair follicle analyses and fibroblast selection studies in 8-azaguanine and 6-thioguanine medium showed a non-carrier phenotype in three of the female heterozygotes, whereas X-inactivation mosaicism was demonstrated in one heterozygote. A possible explanation for the apparent non-random X-inactivation in this family is the co-existence of the hprt mutation with an undefined X-linked lethal mutation. This observation is of practical relevance for carrier detection in other Lesch-Nyhan families. 相似文献
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