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21.
Yanji Qu Lin Zhuo Na Li Yiqing Hu Weihua Chen Yun Zhou Jinwei Wang Qingmei Tao Jing Hu Xiaolu Nie Siyan Zhan 《PloS one》2015,10(4)
International hospital-based studies have indicated a high risk of cognitive impairment after stroke, evidence from community-based studies in China is scarce. To determine the prevalence of post-stroke cognitive impairment (PSCI) and its subtypes in stroke survivors residing in selected rural and urban Chinese communities, we conducted a community-based, cross-sectional study in 599 patients accounting for 48% of all stroke survivors registered in the 4 communities, who had suffered confirmed strokes and had undergone cognitive assessments via the Montreal Cognitive Assessment (MoCA), Mini-Mental State Examination (MMSE), and Hachinski Ischemia Scale (HIS). Detection of PSCI was based on scores in these neuropsychological scales. Factors potentially impacting on occurrence of PSCI were explored by comparing demographic characteristics, stroke features, and cardiovascular risk factors between patients with and without PSCI. The overall prevalence of PSCI was 80.97% (95%CI: 77.82%-84.11%), while that of non-dementia PSCI (PSCI-ND) and post-stroke vascular dementia (PSD) was 48.91% (95%CI: 44.91%-52.92%) and 32.05% (95%CI: 28.32%-35.79%), respectively. Prior stroke and complications during the acute phase were independent risk factors for PSCI. The risk of recurrent stroke survivors having PSCI was 2.7 times higher than for first-episode survivors, and it was 3 times higher for those with complications during the acute phase than for those without. The higher prevalence of PSCI in this study compared with previous Chinese studies was possibly due to the combined effects of including rural stroke survivors, a longer period from stroke onset, and different assessment methods. There is an urgent need to recognize and prevent PSCI in stroke patients, especially those with recurrent stroke and complications during the acute phase. 相似文献
22.
Nirmal Mazumder Rodney K. Lyn Ragunath Singaravelu Andrew Ridsdale Douglas J. Moffatt Chih-Wei Hu Han-Ruei Tsai John McLauchlan Albert Stolow Fu-Jen Kao John Paul Pezacki 《PloS one》2013,8(6)
Hepatitis C virus (HCV) co-opts hepatic lipid pathways to facilitate its pathogenesis. The virus alters cellular lipid biosynthesis and trafficking, and causes an accumulation of lipid droplets (LDs) that gives rise to hepatic steatosis. Little is known about how these changes are controlled at the molecular level, and how they are related to the underlying metabolic states of the infected cell. The HCV core protein has previously been shown to independently induce alterations in hepatic lipid homeostasis. Herein, we demonstrate, using coherent anti-Stokes Raman scattering (CARS) microscopy, that expression of domain 2 of the HCV core protein (D2) fused to GFP is sufficient to induce an accumulation of larger lipid droplets (LDs) in the perinuclear region. Additionally, we performed fluorescence lifetime imaging of endogenous reduced nicotinamide adenine dinucleotides [NAD(P)H], a key coenzyme in cellular metabolic processes, to monitor changes in the cofactor’s abundance and conformational state in D2-GFP transfected cells. When expressed in Huh-7 human hepatoma cells, we observed that the D2-GFP induced accumulation of LDs correlated with an increase in total NAD(P)H fluorescence and an increase in the ratio of free to bound NAD(P)H. This is consistent with an approximate 10 fold increase in cellular NAD(P)H levels. Furthermore, the lifetimes of bound and free NAD(P)H were both significantly reduced – indicating viral protein-induced alterations in the cofactors’ binding and microenvironment. Interestingly, the D2-expressing cells showed a more diffuse localization of NAD(P)H fluorescence signal, consistent with an accumulation of the co-factor outside the mitochondria. These observations suggest that HCV causes a shift of metabolic control away from the use of the coenzyme in mitochondrial electron transport and towards glycolysis, lipid biosynthesis, and building of new biomass. Overall, our findings demonstrate that HCV induced alterations in hepatic metabolism is tightly linked to alterations in NAD(P)H functional states. 相似文献
23.
P Hu G Parenti J Keulemans A T Hoogeveen 《Biochemical and biophysical research communications》1990,167(2):520-527
The catalytic and immunological properties of acid phosphatases (EC 3.1.3.2.) in different tissues were studied. It was demonstrated that high uptake forms of lysosomal enzymes like beta-galactosidase isolated from human platelets and bovine testis are mature enzymes, which have not lost their mannose-6phosphate marker. The results presented indicate that this phenomenon is related to a low activity or the complete absence of the lysosomal tartrate sensitive acid phosphatase activity in the tissues concerned. 相似文献
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25.
Yan-Hong He Guo-Gui Ning Ya-Lin Sun Yan Hu Xing-Yu Zhao Man-Zhu Bao 《Molecular breeding : new strategies in plant improvement》2010,26(1):19-29
A male sterile line was isolated in marigold (Tagetes erecta L.) and cytological analysis determined this to be a novel genic male sterility trait (Tems). Through the use of amplified fragment length polymorphisms (AFLPs) and bulked segregant analysis (BSA), tightly linked
markers of Tems were identified with a view towards a map-based cloning strategy. It was found that spontaneous homeotic conversion of floral
organs was the underlying cause of the male sterility in this marigold line. Thus, petals of male sterile plants resembled
sepal-like structures and the stamens were partially converted to styles, although without the full characteristics or function
of the true style organs. We have constructed a fine marker-based map for the Tems gene. This is intended to provide a tool for marker assisted selection (MAS) strategies in hybrid breeding and map-based
cloning strategies for the male sterility locus. We discuss the significance of this spontaneously derived genic male sterility
trait relating to the homeotic conversion of floral organs in marigold. 相似文献
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28.
用云南山楂(Crataegus scabrifolia(Franch.)Rehd.)成年树茎尖和实生芽两种不同发育阶段的材料为外殖体,诱导它们休眠芽萌动,丛生芽条并诱导芽条生根。实验结果如下:1.以成年态的云南山楂侧芽为外植体,培养在附加IAA 0.1—0.5mg/l+6-BA 1-2mg/l的MS培养基上可诱导芽的萌发;将芽继代培养在附加0.5—1mg/l 6-BA的SH或MS培养基上,40天后芽数增殖4—6倍;将芽条截下置于1/2MS培养基上,附加不同浓度的IAA或IBA,可得到50—80%的生根率。2.以实生芽为外殖体,在相同条件下,则20天后芽数增殖便可获4—6倍;98%以上生根。结果表明:云南山楂的幼年态要比成年态易脱分化和再分化。 相似文献
29.
香荚兰种子的无菌萌发试验 总被引:1,自引:0,他引:1
香荚兰(Vanilla planifolia)是兰科、香荚兰属植物,主产于湿热地区。香荚兰的果实是国际上重要的食用香料的原料。大约在1960年,我国引入香荚兰试栽。生产上,通常用扦插法繁殖;但如用种子繁殖,虽然结实较晚(约7至8年开始结实,较扦插苗晚4—5年),但结实期长,盛产期可维持约15年。而且,在杂交育种过程中,一定要用种子繁殖。 相似文献
30.
Purification and properties of formylglutamate amidohydrolase from Pseudomonas putida. 总被引:4,自引:3,他引:1
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Formylglutamate amidohydrolase (FGase) catalyzes the terminal reaction in the five-step pathway for histidine utilization in Pseudomonas putida. By this action, N-formyl-L-glutamate (FG) is hydrolyzed to produce L-glutamate plus formate. Urocanate, the first product in the pathway, induced all five enzymes, but FG was able to induce FGase alone, although less efficiently than urocanate did. This induction by FG resulted in the formation of an FGase with electrophoretic mobility identical to that of the FGase induced by urocanate. A 9.6-kilobase-pair HindIII DNA fragment containing the P. putida FGase gene was cloned into the corresponding site on plasmid pBEU1 maintained in Escherichia coli. Insertion of the fragment in either orientation on the vector resulted in expression, but a higher level was noted in one direction, suggesting that the FGase gene can be expressed from either of two vector promoters with different efficiencies or from a single vector promoter in addition to a less efficient Pseudomonas promoter. FGase was purified 1,110-fold from the higher-expression clone in a yield of 10% through six steps. Divalent metal ions stimulated activity, and among those tested (Co, Fe, Zn, Ca, Ni, Cd, Mn, and Mg), Co(II) was the best activator, followed by Fe(II). FGase exhibited a Km of 14 mM for FG and a specific activity of 100 mumol/min per mg of protein in the presence of 5 mM substrate and 0.8 mM CoCl2 at 30 degrees C. The enzyme was maximally active in the range of pH 7 to 8. FGase was found to be a monomer of molecular weight 50,000. N-Acetyl-L-glutamate was not a substrate for the enzyme, but both it and N-formyl-L-aspartate were competitive inhibitors of formylglutamate hydrolysis, exhibiting Ki values of 6 and 9 mM, respectively. The absence of FGase activity as an integral part of histidine breakdown in most other organisms and the somewhat uncoordinated regulation of FGase synthesis with that of the other hut enzymes in Pseudomonas suggest that the gene encoding its synthesis may have evolved separately from the remaining hut genes. 相似文献