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The cause of the pregnancy condition preeclampsia (PE) is thought to be endothelial dysfunction caused by oxidative stress. As abnormal glucose tolerance has also been associated with PE, we use a fluorinated-mimic of this metabolite to establish whether any oxidative damage to lipids and proteins in the erythrocyte membrane has increased cell membrane permeability. Data were acquired using 19F Dynamic-NMR (DNMR) to measure exchange of 3-fluoro-3-deoxyglucose (3-FDG) across the membrane of erythrocytes from 10 pregnant women (5 healthy control women, and 5 from women suffering from PE). Magnetisation transfer was measured using the 1D selective inversion and 2D EXSY pulse sequences, over a range of time delays. Integrated intensities from these experiments were used in matrix diagonalisation to estimate the values of the rate constants of exchange and membrane permeability. No significant differences were observed for the rate of exchange of 3-FDG and membrane permeability between healthy pregnant women and those suffering from PE, leading us to conclude that no oxidative damage had occurred at this carrier-protein site in the membrane. 相似文献
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Kazuma Nakano Akino Shiroma Makiko Shimoji Hinako Tamotsu Noriko Ashimine Shun Ohki Misuzu Shinzato Maiko Minami Tetsuhiro Nakanishi Kuniko Teruya Kazuhito Satou Takashi Hirano 《Human cell》2017,30(3):149-161
PacBio RS II is the first commercialized third-generation DNA sequencer able to sequence a single molecule DNA in real-time without amplification. PacBio RS II’s sequencing technology is novel and unique, enabling the direct observation of DNA synthesis by DNA polymerase. PacBio RS II confers four major advantages compared to other sequencing technologies: long read lengths, high consensus accuracy, a low degree of bias, and simultaneous capability of epigenetic characterization. These advantages surmount the obstacle of sequencing genomic regions such as high/low G+C, tandem repeat, and interspersed repeat regions. Moreover, PacBio RS II is ideal for whole genome sequencing, targeted sequencing, complex population analysis, RNA sequencing, and epigenetics characterization. With PacBio RS II, we have sequenced and analyzed the genomes of many species, from viruses to humans. Herein, we summarize and review some of our key genome sequencing projects, including full-length viral sequencing, complete bacterial genome and almost-complete plant genome assemblies, and long amplicon sequencing of a disease-associated gene region. We believe that PacBio RS II is not only an effective tool for use in the basic biological sciences but also in the medical/clinical setting. 相似文献
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A Neuro-Comparative Study between Single/Successive Thorium Dose Intoxication and Alginate Treatment
Mohamed M. Rezk 《Biological trace element research》2018,185(2):414-423
The adult male albino rats were grouped into five groups (control group and four variably treated groups with thorium (Th) in single or successive with or without alginate treatment). The IP administration of thorium nitrate (13.6 mg/kg b.wt.) induced a regional distribution and accumulation ordered as cerebellum > cerebral cortex > brain stem > hippocampus > hypothalamus > striatum. Also, it induces a significant increase in Na+, Ca2+, and Fe3+ ion content and malondialdehyde (MDA) level while K+ ions and glutathione (GSH) level were significantly decreased. On the other hand, the daily oral administration of 5% alginate showed a significant decreasing in the accumulation of thorium in the different brain areas and mitigated its hazardous effects. By the alginate treatment, Na+, Ca2+, Fe3+, and level of MDA were declined while K+ ions and GSH level showed a significant increase. The improvement of the investigated parameters was attributed to the specific chelating, regeneration, and antioxidant properties of the alginate. So, alginate administration could ameliorate the hazardous effects of thorium nitrate. 相似文献
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Xiuqing Wang Daphne Moutsoglou 《In vitro cellular & developmental biology. Animal》2009,45(10):584-591
Primary fibroblast-like cells isolated from the peripheral blood of a healthy pig were immortalized by transduction of cells
with a replication-defective retrovirus vector expressing the E6/E7 proteins of human papillomavirus type 16 (pLXSN-16E6E7).
The immortalized cells grow rapidly in cell culture and exhibit a distinct cell surface phenotype that was positive for CD90,
CD44, collagen I, and vimentin and negative for CD14 and MHC II. Additionally, these immortalized blood derived-fibroblast-like
cells had the potential to differentiate into osteoblasts and adipocytes in vitro as evidenced by the deposition of calcium,
increased alkaline phosphatase activity, upregulated osteogenic and adipogenic marker gene expression, and accumulation of
fat droplets in cells when osteogenic (dexamethasone, ascorbic acid, and β-glycerophosphate) or adipogenic supplements (dexamethasone,
3-isobutyl-1-methylxanthine, indomethacin, and insulin) were added to the culture. Overall, the results suggest that the immortalized
blood-derived fibroblast-like cells exhibit some of the features of mesenchymal precursor cells, which may have implications
in tissue repair and remodeling process. 相似文献
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Roberta L. Millstein 《Journal of the history of biology》2008,41(2):339-367
Biologists and philosophers have been extremely pessimistic about the possibility of demonstrating random drift in nature,
particularly when it comes to distinguishing random drift from natural selection. However, examination of a historical case
– Maxime Lamotte’s study of natural populations of the land snail, Cepaea nemoralis in the 1950s – shows that while some pessimism is warranted, it has been overstated. Indeed, by describing a unique signature
for drift and showing that this signature obtained in the populations under study, Lamotte was able to make a good case for
a significant role for␣drift. It may be difficult to disentangle the causes of drift and selection acting in a population,
but it is not (always) impossible. 相似文献
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