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11.
Endothelial progenitor cells (EPC) participate in revascularization and angiogenesis. EPC can be cultured in vitro from mononuclear cells of peripheral blood, umbilical cord blood or bone marrow; they also can be transdifferentiated from mesenchymal stem cells (MSC). We isolated EPCs from Wharton's jelly (WJ) using two methods. The first method was by obtaining MSC from WJ and characterizing them by flow cytometry and their adipogenic and osteogenic differentiation, then applying endothelial growth differentiating media. The second method was by direct culture of cells derived from WJ into endothelial differentiating media. EPCs were characterized by morphology, Dil-LDL uptake/UEA-1 immunostaining and testing the expression of endothelial markers by flow cytometry and RT-PCR. We found that MSC derived from WJ differentiated into endothelial-like cells using simple culture conditions with endothelium induction agents in the medium. 相似文献
12.
【背景】杨树溃疡病是一种主要由葡萄座腔菌引起的杨树枝干病害,危害严重。前期从杨树中分离到一株内生拮抗细菌N6-34,研究表明该菌株拮抗效果好,对多种植物病原菌均有较强的拮抗作用。【目的】对拮抗细菌N6-34产生的抗菌活性物质进行分离纯化,并鉴定了活性物质组分的结构。【方法】通过硫酸铵盐析、甲醇抽提、分子筛、高效液相色谱等方法分离纯化N6-34菌株的抗菌活性物质,并对其进行结构鉴定。【结果】N6-34菌株发酵液经多步分离纯化,共获得14个组分,其中有13个组分具有抗菌活性,经一级质谱分析,获得了13种抗菌活性组分的分子量;经二级质谱分析,将13种抗菌活性物质鉴定为Fengycin A或Fengycin B的同系物或同分异构体。【结论】从N6-34菌株发酵液中分离获得了13种抗菌成分,为杨树溃疡病的生物防治提供了理论依据。 相似文献
13.
Twenty European domestic cats were each infected with 15,000 protoscoleces of Echinococcus multilocularis extracted from metacestodes grown in experimentally infected common voles (Microtus arvalis). Sixteen days after infection, ten cats were treated with a broad-spectrum anthelmintic and acaricide comprising praziquantel and milbemycin oxime. Five days later treated and untreated cats were euthanized and the intestine examined for E. multilocularis. Five of ten untreated cats were infected with E. multilocularis with worm burdens ranging from 235 to 1920 worms per cat. No E. multilocularis were recovered from any of the treated cats. This study has demonstrated that this new combination broad spectrum anthelmintic and acaricide for cats is highly efficacious against E. multilocularis and the relevance of this is discussed. 相似文献
14.
The causative agent of alveolar hydatidosis in humans, the fox tapeworm Echinococcus multilocularis, is extending its geographical range in Europe and has been found in domestic cats in some areas. A dermally applied cestocidal treatment for domestic cats has been developed and the efficacy of this treatment is reported. Thirty purpose-bred cats were experimentally infected each with 10000 protoscoleces of Echinococcus multilocularis. Ten days later one group of ten cats was treated with Droncit(R) Spot-on (Praziquantel) 4% w/v dermally in one place on the dorsal aspect of the neck at a dose of 8 mg/kg. Eleven days later (21 days p.i.) a second group of ten cats was also treated with Droncit(R) Spot-on the same way. One group of ten cats was left untreated as controls. Twenty three days after infection the cats were examined for the presence of E. multilocularis tapeworms. No E. multilocularis were recovered from any of the cats in either of the treated groups. Echinococcus multilocularis were recovered from eight of the ten cats left untreated as controls. The worm burdens in the untreated cats were 0, 0, 5, 15, 75, 110, 220, 815, 2635, and 3045 worms per cat. The worms ranged in development from the three to four segment stage. Many of the E. multilocularis with four segments contained unshelled eggs in the terminal segment. This study indicates that Droncit(R) Spot-on (Praziquantel) 4% w/v applied dermally at 8 mg/kg is highly effective in removing E. multilocularis from the small intestine of cats infected with immature and mature (prepatent) infections of E. multilocularis. In the cats with the mature infections all tapeworms were absent from the small intestine within 2 days of treatment. 相似文献
15.
Steiner H Kostka M Romig H Basset G Pesold B Hardy J Capell A Meyn L Grim ML Baumeister R Fechteler K Haass C 《Nature cell biology》2000,2(11):848-851
Endoproteolysis of beta-amyloid precursor protein (betaAPP) and Notch requires conserved aspartate residues in presenilins 1 and 2 (PS1 and PS2). Although PS1 and PS2 have therefore been proposed to be aspartyl proteases, no homology to other aspartyl proteases has been found. Here we identify homology between the presenilin active site and polytopic aspartyl proteases of bacterial origin, thus supporting the hypothesis that presenilins are novel aspartyl proteases. 相似文献
16.
17.
MORAIS PAULO AMORIM ANTÓNIO VIEIRA DA SILVA CLÁUDIA RIBEIRO TERESA COSTA SANTOS JORGE AFONSO COSTA HELOÍSA 《Journal of genetics》2015,94(3):509-512
Journal of Genetics - 相似文献
18.
JG Hansen W Gao J Dupuis GT O’Connor W Tang M Kowgier A Sood SA Gharib LJ Palmer M Fornage SR Heckbert BM Psaty SL Booth SUNLIGHT Consortium Patricia A Cassano 《Respiratory research》2015,16(1)
Background
Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults.Methods
We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV1) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV1 in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV1 in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts.Results
We found a positive cross-sectional association between 25(OH)D and FEV1 in FHS Offspring and Third Generation participants (P = 0.004). There was little or no association between 25(OH)D and longitudinal change in FEV1 in Third Generation participants (P = 0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV1 (gene-based P < 0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV1 in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P = 0.09).Conclusions
Serum 25(OH)D status was associated with cross-sectional FEV1, but not longitudinal change in FEV1. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV1 and is a promising candidate gene for further studies.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0238-y) contains supplementary material, which is available to authorized users. 相似文献19.
20.
Christof Janko Stefan Linke Thomas Romig Dorothea Thoma Wolfgang Schröder Andreas König 《European Journal of Wildlife Research》2011,57(5):1033-1042
This study investigated the epidemiological and ecological factors to assess the infection pressure of alveolar echinococcosis
to human which are living in villages and small towns. Foxes and fox faeces were examined for Echinococcus multilocularis and foxes were observed by radio telemetry in Upper Bavaria, Germany. Forty-three percent of the village foxes (n = 65) had been infected with E. multilocularis. This prevalence rate did not differ significantly from the prevalence among rural foxes, which was 39% (n = 33; χ
2 = 0.12, df = 1, p = 0.727) determined by the intestinal scraping technique. PCR analyses of fox faeces showed a higher infection rate of 35%
(n = 26) among rural foxes than among foxes in villages and small towns (26%, n = 69; χ
2 = 0.68, df = 1, p = 0.411). One quarter of the fox faecal samples come from private gardens of residents. The radio-tracking study on 17 foxes
showed that foxes preferred the built-up area and grassland outside the villages. Village foxes concentrated their activity
within a range of 500 m around the settlement. Sixty-four percent of all bearings for radio-tracked foxes showed positions
in areas outside the town, and 36% of bearings were within the settlement. Village foxes, which are infected with E. multilocularis, are able to carry the parasite continuously into settlements and fox faeces present an immediate source of infection to
humans, especially within their gardens. Therefore, foxes are responsible for environmental E. multilocularis egg contamination in the vicinity of humans, leading to an infection risk to inhabitants of villages and small towns. 相似文献