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41.
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J R van Der Ploeg R Iwanicka-Nowicka T Bykowski M M Hryniewicz T Leisinger 《The Journal of biological chemistry》1999,274(41):29358-29365
43.
Steven J. Tucker David McClelland Kristina Sep?i? Roderick H. Scott 《生物化学与生物物理学报:生物膜》2003,1614(2):171-181
The ability of two alkyl pyridinium sponge toxin preparations (poly-APS and halitoxin) to form transient pores/lesions in cell membranes and allow transfection of plasmid cDNA have been investigated using HEK 293 cells. Poly-APS and halitoxin preparations caused a collapse in membrane potential, reductions in input resistance and increased Ca2+ permeability. At least partial recovery was observed after poly-APS application but recovery was more rarely seen with halitoxin. The transfection with plasmid cDNAs for an enhanced green fluorescent protein (EGFP) and human tumour necrosis factor receptor 2 (TNFR2) was assessed for both toxin preparations and compared with lipofectamine. Stable transfection was achieved with poly-APS although it was less efficient than lipofectamine. These results show that viable cells transfected with alien cDNA can be obtained using novel transient pore-forming alkyl pyridinium sponge toxins and a simple pre-incubation protocol. This provides the first proof of principle that pore-forming alkyl pyridinium compounds can be used to deliver cDNA to the intracellular environment without permanently compromising the plasma membrane. 相似文献
44.
V V Snitinski? 《Zhurnal evoliutsionno? biokhimii i fiziologii》1989,25(5):583-588
[2-14C] leucine, [1-14C] alanine, [1-14C] glucose, [1-14C] lactate and [1-14C] pyruvate utilization in the protein synthesis has been studied in vivo at early stages of postnatal development of piglets. It has been established, that during the first 24 hours after birth the protein synthesis intensity, judging by [2-14C] leucine incorporation, in liver, skeletal muscle, duodenal wall and subcutaneous tissue of piglets increases 5, 7, 6.5 and 2.1 times respectively. At the age of 1-2 h the radioactive carbon incorporation from [1-14C] glucose into the brain proteins is more pronounced than into the proteins of liver and skeletal muscle. During the first days of life the intensity of the label incorporation from [1-14C] glucose into liver and skeletal muscle proteins of piglets is enhanced, whereas in brain it remains at the same level. The degree of 14C carbon incorporation from [1-14C]-alanine, [1-14C] pyruvate and [1-14C] lactate into the liver and skeletal muscle proteins of 5-days-old piglets is approximately the same, 14C substrates of protein synthesis in brain and subcutaneous adipose tissue having some peculiarities. 相似文献
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A Ba?sset J Cotonat P Montastruc 《Comptes rendus des séances de la Société de biologie et de ses filiales》1975,169(2):444-448
The authors have studied in the dog--normal or diabetic insipidus after hypothalamic lesion--submitted to oral ingestion of ethanol the effects of a few antidiuretic drug: chlorpropamid, atromid-S, carbamazepin and carisoprodol. The carisoprodol only can reduce the diuresis and the drinking provoked by ethanol. 相似文献
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Carotenoids present in lipids extracted from the cyanobacterium Synechococcus 6716 indicate trans-membrane potential in proteoliposomes reconstituted from these lipids and the ATPase complex isolated from the same organism. A carotenoid absorbance band shift to a longer wavelength is obtained with valinomycin-induced potassium ion diffusion potentials, irrespective of the polarity of the potassium gradient. In contrast to this, the (externally added) probe oxonol VI only shows an absorbance band shift when the external potassium ion concentration is higher than the internal one. In liposomes without ATPase complex, no carotenoid absorbance band shifts were observed. 相似文献
49.
Epithelial ovarian carcinoma (EOC), the major cause of gynaecological cancer death, is a heterogeneous disease classified into five subtypes. Each subtype has distinct clinical characteristics and is associated with different genetic risk factors and molecular events, but all are treated with surgery and platinum/taxane regimes. Tumour progression and chemoresistance is generally associated with major metabolic alterations, notably altered mitochondrial function(s). Here, we report for the first time that the expression of the mitochondrial regulators PGC1α and TFAM varies between EOC subtypes; furthermore, we have identified a profile in clear-cell carcinoma consisting of undetectability of PGC1α/TFAM, and low ERα/Ki-67. By contrast, high-grade serous carcinomas were characterised by a converse state of PGC1α/TFAM, ERα positivity and a high Ki-67 index. Interestingly, loss of PGC1α/TFAM and ERα was found also in a non-clear cell EOC cell line made highly resistant to platinum in vitro. Similar to clear-cell carcinomas, these resistant cells also showed accumulation of glycogen. Altogether, our data provide mechanistic insights into the chemoresistant nature of ovarian clear-cell carcinomas. Furthermore, these findings corroborate the need to take into account the diversity of EOC and to develop subtype specific treatment strategies. 相似文献
50.