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1.
Baiba Jansone Inga Kadish Thomas van Groen Ulrika Beitnere Doyle Ray Moore Aiva Plotniece Karlis Pajuste Vija Klusa 《PloS one》2015,10(6)
Ca2+ blockers, particularly those capable of crossing the blood-brain barrier (BBB), have been suggested as a possible treatment or disease modifying agents for neurodegenerative disorders, e.g., Alzheimer’s disease. The present study investigated the effects of a novel 4-(N-dodecyl) pyridinium group-containing 1,4-dihydropyridine derivative (AP-12) on cognition and synaptic protein expression in the brain. Treatment of AP-12 was investigated in wild type C57BL/6J mice and transgenic Alzheimer’s disease model mice (Tg APPSweDI) using behavioral tests and immunohistochemistry, as well as mass spectrometry to assess the blood-brain barrier (BBB) penetration. The data demonstrated the ability of AP-12 to cross the BBB, improve spatial learning and memory in both mice strains, induce anxiolytic action in transgenic mice, and increase expression of hippocampal and cortical proteins (GAD67, Homer-1) related to synaptic plasticity. The compound AP-12 can be seen as a prototype molecule for use in the design of novel drugs useful to halt progression of clinical symptoms (more specifically, anxiety and decline in memory) of neurodegenerative diseases, particularly Alzheimer’s disease. 相似文献
2.
Karlis Abele 《Protoplasma》1951,40(2):324-337
Ohne Zusammenfassung 相似文献
3.
Alexander P. Wolfe Adam Z. Csank Alberto V. Reyes Ryan C. McKellar Ralf Tappert Karlis Muehlenbachs 《PloS one》2012,7(9)
We report exceptional preservation of fossil wood buried deeply in a kimberlite pipe that intruded northwestern Canada’s Slave Province 53.3±0.6 million years ago (Ma), revealed during excavation of diamond source rock. The wood originated from forest surrounding the eruption zone and collapsed into the diatreme before resettling in volcaniclastic kimberlite to depths >300 m, where it was mummified in a sterile environment. Anatomy of the unpermineralized wood permits conclusive identification to the genus Metasequoia (Cupressaceae). The wood yields genuine cellulose and occluded amber, both of which have been characterized spectroscopically and isotopically. From cellulose δ18O and δ2H measurements, we infer that Early Eocene paleoclimates in the western Canadian subarctic were 12–17°C warmer and four times wetter than present. Canadian kimberlites offer Lagerstätte-quality preservation of wood from a region with limited alternate sources of paleobotanical information. 相似文献
4.
Karlis Abele 《Protoplasma》1936,25(1):92-114
Ohne Zusammenfassung 相似文献
5.
The carotenoid content in the petals of fourteen Medicago species was examined, together with eight species studied previously, caratenoids in all the known perennials of the genus are reported. The species can be arranged in relationship groups on the basis of their interfertility. No major carotenoid was species- or groupspecific; a few minor pigments, however, were group- or species-specific. The amount of carotenoids ranged from 7 μg/g dry matter in violet-flowered M. sativa to 2120 μg/g in brownish-yellow M. platycarpos. Xanthophylls constituted 76–99% of the total, with lutein as the major component. β-Carotene, lutein and flavoxanthin were ubiquitous in petals. In M sativa leaves β-carotene, lutein, violaxanthin and neoxanthin constituted 88% of the total. The xanthophylls were esterified in petals but not in leaves. 相似文献
6.
Karlis Lesins 《Biotechnic & histochemistry》1954,29(5):261-264
Numerous mitotic plates of contracted and well-spread chromosomes may be obtained from root tips of plants set on melting ice or snow overnight at room temperature. After 1:3 acetic-alcohol fixation for 0.5 to 3 hours the material is mordanted in a mixture of 7 parts of alcohol plus 21/2 parts of 3% ferric ammonium sulfate for 3 hours to overnight. This solution may be used as storage fluid for flower buds. Deep chromosome coloration without precipitates is secured by staining in a few drops of aceto-carmine for 10-15 minutes after which the tissues are softened by heating in aceto-carmine diluted with 3 parts of 45% acetic acid. 相似文献
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Briviba K Watzl B Nickel K Kulling S Bös K Haertel S Rechkemmer G Bub A 《Redox report : communications in free radical research》2005,10(6):325-331
This study investigated whether a 21.1 km (half-marathon) or a 42.195 km (marathon) run modulates DNA damage, antioxidant capacity in lymphocytes and plasma, and the immune system in healthy hobby runners. Ten and 12 volunteers who completed the Baden-Marathon race in Karlsruhe with a running distance of 21.1 km and 41.195 km, respectively, were assessed 10 days before and immediately after the finish. There was no increase in the levels of endogenous DNA strand breaks immediately after half-marathon or marathon races. A statistically significant increase in the levels of oxidative DNA damage in lymphocytes was found using endonuclease III but not formamidopyrimidine glycolase (Fpg). The resistance of DNA to oxidative damage induced by hydrogen peroxide in isolated lymphocytes was significantly decreased after both races. The levels of plasma antioxidants such as alpha-tocopherol, beta-carotene and lycopene were close to, or higher than, those considered optimal for reducing the risk of cardiovascular diseases and there were no significant changes after the races in antioxidant capacity of LDL (lag-time test) or plasma in ORAC, TEAC or paraoxonase assays. The number and percentage of granulocytes and monocytes able to generate oxidative burst were significantly increased after both races, but the lytic activity of NK cells was significantly increased at the end of the half-marathon; no effect was observed in the marathon runners. Thus, oxidative DNA damage in lymphocytes, decreased the antioxidant capacity to protect lymphocytes against DNA strand breaks and increased the formation of reactive species by phagocytes in well-nourished hobby runners indicating moderate oxidative damage during such high-intensity exercise. 相似文献
9.
Michael D. Kluetz Karlis Adamsons James E. Flynn Jr. 《Preparative biochemistry & biotechnology》2013,43(5):615-631
The level of diamine oxidase in pea seedling stems has been determined as a function of time after germination in both etiolated and non-etiolated plants. The maximum amount of enzyme per plant is obtained between 11 and 13 days. The amount of activity per gram of tissue appears to be proportional to the rate of growth. We describe an efficient method of isolation of pea seedling stem diamine oxidase from 12-day-old etiolated seedlings, a procedure that brings the enzyme to purity after a 97-fold purification. A new assay procedure for pea seedling diamine oxidase is detailed and compared to previously used methods. The kinetic parameters for three common substrates have also been determined. SDS-acrylamide gel electrophoresis, gel filtration chromatography and copper analyses have been used to determine that pea seedling diamine oxidase exists as a dimer of two apparently identical subunits, the dimer molecular weight being about 190,000. The isoelectric point of this enzyme was determined to be 6.5. 相似文献
10.
The paper proposes a hybrid system based approach for modelling of intracellular networks and introduces a restricted subclass of hybrid systems – HSM – with an objective of still being able to provide sufficient power for the modelling of biological systems, while imposing some restrictions that facilitate analysis of systems described by such models. 相似文献