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排序方式: 共有61条查询结果,搜索用时 187 毫秒
1.
A new continuous line of goldfish somatic cells, designated SJU-1 has been continuously subcultured over a 39-month period. Best growth was obtained at 20°C over a pH range of 6.8–7.2. The minimal and optimal seed inocula, in terms of per cent cell increase, were determined to be 1.1 × 106 and 2.5 × 106 , respectively. The susceptibility of the SJU-1 line to infectious pancreatic necrosis virus offers an available assay system for goldfish in vivo and goldfish cells in vitro interferon studies. Chromosomal analyses of the line were also carried out. 相似文献
2.
Sanja Cicko Melanie Grimm Korcan Ayata Jessica Beckert Anja Meyer Madelon Hossfeld Gernot Zissel Marco Idzko Tobias Müller 《Respiratory research》2015,16(1)
Rationale
Pulmonary fibrosis is a progressive disease with only few treatment options available at the moment. Recently, the nucleoside uridine has been shown to exert anti-inflammatory effects in different animal models, e.g. in acute lung injury or bronchial asthma.Method
Therefore, we investigated the influence of uridine supplementation on inflammation and fibrosis in the classical bleomycin model. Male C57BL/6 mice received an intratracheal injection of bleomycin on day 0 and were treated intraperitoneally with uridine or vehicle. The degree of inflammation and fibrosis was assessed at different time points.Results
Uridine administration resulted in attenuated inflammation, as demonstrated by reduced leukocytes and pro-inflammatory cytokines in the broncho-alveolar lavage (BAL) fluid. Furthermore, collagen deposition in the lung interstitium was also reduced by uridine supplementation. Similar results were obtained in a model in which animals received repeated intraperitoneal bleomycin injections. In addition uridine inhibited collagen and TGF-ß synthesis by primary lung fibroblasts, the release of pro-inflammatory cytokines by human lung epithelial cells, as well as the production of reactive oxygen species by human neutrophils.Conclusion
In summary, we were able to show that uridine has potent anti-inflammatory and anti-fibrotic properties. As uridine supplementation has been shown to be well tolerated and safe in humans, this might be a new therapeutic approach for the treatment of fibrotic lung diseases. 相似文献3.
4.
Caroline Tassy Anne Partier Michel Beckert Catherine Feuillet Pierre Barret 《Plant Cell, Tissue and Organ Culture》2014,119(1):171-181
The feasibility of map-based cloning in wheat has been demonstrated recently, opening new perspectives for a better understanding of wheat plant biology and for accelerating wheat improvement in the coming decades. To validate the function of candidate genes, an efficient transformation system is needed. Here, we have performed two methods for wheat transformation using particle bombardment that ensures the production of transgenic plants with simple integration patterns for research purposes and stable transgene expression for accurate and rapid validation of gene function. To establish this method, we used the bar and pmi selectable genes either as part of whole plasmids, gene cassettes (obtained by PCR or purified on agarose gels), or as dephosphorylated cassettes. The analysis of about 300 transgenic plants showed that the use of gene cassettes or dephosphorylated gene cassettes leads to a majority (50–60 %) of simple integration events. This is significantly higher than the number of simple events obtained with whole plasmids (9–25 %). Moreover, the decrease of the quantity of DNA from 500 to 5 ng/µl for PCR-amplified cassettes used for transformation increased the number of single integration events. The transformation efficiency remained stable at 2.5 %, and a higher number of plants expressing the transgenes were obtained with the dephosphorylated cassette. No correlation was observed between the complexity of the events and stability of expression of the transgene, suggesting that plasmid sequences could be involved on transgene silencing. The inheritability of the transgene was demonstrated in T1 and T2 generations. These results show that biolistic transformation of dephosphorylated gene cassettes provides an easy and efficient route to produce backbone vector-free transgenic wheat carrying and expressing intact and single transgenes. 相似文献
5.
A major locus expressed in the male gametophyte with incomplete penetrance is responsible for in situ gynogenesis in maize 总被引:3,自引:0,他引:3
Barret P Brinkmann M Beckert M 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,117(4):581-594
In flowering plants, double fertilization occurs when the egg cell and the central cell are each fertilized by one sperm cell. In maize, some lines produce pollen capable of inducing in situ gynogenesis thereby leading to maternal haploids that originate exclusively from the female plant. In this paper, we present a genetic analysis of in situ gynogenesis in maize. Using a cross between non-inducing and inducing lines, we identified a major locus on maize chromosome 1 controlling in situ gynogenesis (ggi1, for gynogenesis inducer 1). Fine mapping of this locus was performed, and BAC physical contigs spanning the locus were identified using the rice genome as anchor. Genetic component analysis showed that (a) a segregation distortion against the inducer parent was present at this locus, (b) segregation resulted only from male deficiency and (c) there was a correlation between the rate of segregation distortion and the level of gynogenetic induction. In addition, our results showed that the genotype of the pollen determined its capacity to induce the formation of a haploid female embryo, indicating gametophytic expression of the character with incomplete penetrance. We propose the occurrence of a gametophytic-specific process which leads to segregation distortion at the ggi1 locus associated with gynogenetic induction with incomplete penetrance. 相似文献
6.
Twin-ribozyme introns contain a branching ribozyme (GIR1) followed by a homing endonuclease (HE) encoding sequence embedded in a peripheral domain of a group I splicing ribozyme (GIR2). GIR1 catalyses the formation of a lariat with 3 nt in the loop, which caps the HE mRNA. GIR1 is structurally related to group I ribozymes raising the question about how two closely related ribozymes can carry out very different reactions. Modelling of GIR1 based on new biochemical and mutational data shows an extended substrate domain containing a GoU pair distinct from the nucleophilic residue that dock onto a catalytic core showing a different topology from that of group I ribozymes. The differences include a core J8/7 region that has been reduced and is complemented by residues from the pre-lariat fold. These findings provide the basis for an evolutionary mechanism that accounts for the change from group I splicing ribozyme to the branching GIR1 architecture. Such an evolutionary mechanism can be applied to other large RNAs such as the ribonuclease P. 相似文献
7.
Adamec J Beckert R Weiss D Klimesová V Waisser K Möllmann U Kaustová J Buchta V 《Bioorganic & medicinal chemistry》2007,15(8):2898-2906
New hybrid molecules of estrone were synthesized as compounds indicating promising biological activity (antibacterial, antimycobacterial, antifungal, and antiproliferative). The prepared molecules contained various heterocyclic units (pyridine, benzylsulfanyl derivatives of pyridine or derivatives of tetrazole) linked to estrone by n-heptyl bridges. The compounds with charge on molecule (the hybrid pyridinium or benzylsulfanylpyridinium salts) exhibited significant biological activity (antibacterial, antimycobacterial, antifungal, and antiproliferative). On the other hand, the compounds not in the form of salts (omega-(1-phenyl-5-tetrazolylthio)heptylethers of estrone) were inactive. The antimycobacterial activities of three different series of tetrazole derivatives (i.e., the hybrid molecules with estrone, tetrazole-5-thiols, and 5-benzylsulfanyl-1-phenyltetrazoles) with the same substituents on phenyl ring were compared. Amongst them, the 5-benzylsulfanyl-1-phenyltetrazoles were the most potent. 相似文献
8.
Analysis of lipocyte viability after liposuction 总被引:16,自引:0,他引:16
Boschert MT Beckert BW Puckett CL Concannon MJ 《Plastic and reconstructive surgery》2002,109(2):761-5; discussion 766-7
Free fat grafts from liposuction aspirate can be used as donor material for soft-tissue augmentation. The purpose of this study was to attempt to identify a subpopulation of adipose cells within liposuction aspirate with the greatest viability and, it is hoped, a greater chance for increased survival after transplantation. Liposuction samples were obtained from 20 individuals (16 women, four men; age range, 27 to 49 years). These samples were then centrifuged at 50 g. At 2-minute intervals, specimens from three different areas (superficial, middle, deep) were obtained from each specimen. After collagenase degradation, the specimens were stained with trypan blue, and the number of viable cells were counted. The bottom (deepest) layer consistently contained the highest number of viable cells after centrifugation: 250 percent more viable cells when compared with the top layer (p < 0.0001) and 140 percent more viable cells when compared with the middle layer (p < 0.0002). Centrifugation beyond 2 minutes did not increase the number or proportion of viable adipocytes. When using aspirated fat from liposuction for soft-tissue augmentation, centrifugation for 2 minutes at 50 g will stratify the adipocytes, with more viable cells being found at the deepest layer. Using only this bottom portion of the fat layer for transplantation will yield a fat graft with a greater number of viable adipocytes, potentially improving fat graft survival and decreased fat graft resorption. 相似文献
9.
The slow-evolving mitochondrial DNAs of plants have potentially conserved information on the phylogenetic branching of the
earliest land plants. We present the nad2 gene structures in hornworts and liverworts and in the presumptive earliest-branching
vascular land plant clade, the Lycopodiopsida. Taken together with the recently obtained nad2 data for mosses, each class
of bryophytes presents another pattern of angiosperm-type introns conserved in nad2: intron nad2i1 in mosses; intron nad2i3
in liverworts; and both introns, nad2i3 and nad2i4, in hornworts. The lycopods Isoetes and Lycopodium show diverging intron
conservation and feature a unique novel intron, termed nad2i3b. Hence, mitochondrial introns in general are positionally stable
in the bryophytes and provide significant intraclade phylogenetic information, but the nad2 introns, in particular, cannot
resolve the interclade relationships of the bryophyte classes and to the tracheophytes. The necessity for RNA editing to reconstitute
conserved codon entities in nad2 is obvious for all clades except the marchantiid liverworts. Finally, we find that particularly
small group II introns appear as a general feature of the Isoetes chondriome. Plant mitochondrial peculiarities such as RNA
editing frequency, U-to-C type of RNA editing, and small group II introns appear to be genus-specific rather than gene-specific
features. 相似文献
10.
Summary The ability to recover male gametophyte derived plants, which is necessary to get transformed haploid plants, was verified for a hybrid of maize. Using the isolated microspore culture technique, a 9 × 10–5 plant regeneration frequency was obtained. Maize microspores were bombarded with tungsten particles using a PDS He/1000 apparatus. GUS expression in the microspores was maximum with 1.1 m diameter tungsten microprojectiles for 1100 and 1350 psi helium pressures at a 6 cm distance between the launch point and the target cells. Increasing the amount of DNA coated on the microparticles from 1.66 to 4 g DNA/mg of particles allowed a two-fold and four-fold increase of the GUS-expressing microspore frequency for 1100 and 1350 psi helium pressure bombardment, respectively. Optimal concentration of solidifying agent in the bombardment support culture medium was found to be 1%. Cell density ranging from 25000 microspores/bombardment to 100000 microspores/bombardment did not affect the frequency of GUS-expressing microspores. Using these optimal conditions, the maximum frequency of GUS-expressing microspores was found to be about 9 × 10–4, while maintaining an embryo formation frequency about 5 × 10–4.Abbreviations GUS
-glucuronidase
- PEG
polyethylene glycol 相似文献