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排序方式: 共有1177条查询结果,搜索用时 78 毫秒
1.
Franciele Martini Marlon Régis Leite Suzan Gonçalves Rosa Isabella Pregardier Klann Cristina Wayne Nogueira 《Cell biochemistry and function》2020,38(2):213-221
Alzheimer's disease (AD) is a progressive neurodegenerative disorder that has generated scientific interest because of its prevalence in the population. Studies indicate that physical exercise promotes neuroplasticity and improves cognitive function in animal models and in human beings. The aim of the present study was to investigate the effects of strength exercise on the hippocampal protein contents and memory performance in mice subjected to a model of sporadic AD induced by streptozotocin (STZ). Swiss mice received two injections of STZ (3 mg/kg, intracerebroventricular). After 21 days, they began physical training using a ladde. Mice performed this protocol for 4 weeks. After the last exercise training session, mice performed the Morris Water Maze test. The samples of hippocampus were excised and used to determine protein contents of brain-derived neurotrophic factor (BDNF), extracellular signal-regulated kinase-Ca2+ (ERK), calmodulin-dependent protein kinase (CAMKII) and cAMP-response element-binding protein (CREB) signalling pathway. Strength exercise was effective against the decrease in the time spent and distance travelled in the target quadrant by STZ-injected mice. Strength exercise was also effective against the reduction of mature BDNF, tropomyosin receptor kinase B and neuronal nuclear antigen (NeuN) hippocampal protein levels in STZ mice. The decrease in the hippocampal ratio of pERK/ERK, pCAMKII/CAMKII and pCREB/CREB induced by STZ was reversed by strength exercise. Strength exercise decreased Bax/Bcl2 ratio in the hippocampus of STZ-injected mice. The present study demonstrates that strength exercise modulated the hippocampal BDNF/ERK-CAMKII/CREB signalling pathway and suppressed STZ-induced spatial memory impairment in mice. 相似文献
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Factors Associated with Slow Disease Progression in Macaques Immunized with an Adenovirus-Simian Immunodeficiency Virus (SIV) Envelope Priming-gp120 Boosting Regimen and Challenged Vaginally with SIVmac251 下载免费PDF全文
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Kyung Ok Shin Jeong Ryae Jeon Ji Seon Lee Jong Yeon Kim Chu Hee Lee Soon Dong Kim Yeon-Su Yu Doo Hyun Nam 《Biotechnology and Bioprocess Engineering》2006,11(3):240-244
To develop a health-aid preparation of Chinese yam (Dioscorea batatas Decne), lactic acid fermentation was attempted using a mixed starter comprising ofLactobacillus acidophilus, Streptococcus thermophilus, andBifidobacterium bifidus. The anaerobic fermentation of a 5% Chinese yam flour suspension gave a uniform suspension of pH 4.35, containing 7.76×106 CFU/mL lactic acid bacteria (LAB), and which was found to be acceptable to the panel from a sensory assessment. During the
administration of the lactic acid fermented (LAF) Chinese yam to Sprague Dawley rats for 6 weeks, a smaller body weight gain,
but greater excretion of feces were observed, implying the creation of a healthy gastrointestine on the administration of
LAF Chinese yam, which was also confirmed by the gastrointestinal motility of the feed in rats fed on LAF Chinese yam. The
constipation induced by loperamide was further suppressed in a rat group fed on a LAF Chinese yam diet, which was qualified
from healthy gastrointestinal flora established by LAB. A serochemical analysis revealed a slight improvement in the blood
glucose, neutral lipid and total cholesterol concentrations on administration of LAF Chinese yam, suggesting LAF Chinese yam
could be served as a healthy-aid preparation, even for hyperglycemia or hyperlipidemia patients. 相似文献
7.
Ok Tae Kim Nam Hee Yoo Gum Soog Kim Young Chang Kim Kyong Hwan Bang Dong Yun Hyun Seung Hye Kim Min Young Kim 《Plant Cell, Tissue and Organ Culture》2013,112(1):87-93
It has been recognized that ginsenoside Rg3 is not naturally produced in ginseng although this ginsenoside can accumulate in red ginseng as the result of a thermal process. In order to determine whether or not Rg3 is synthesized in ginseng, hairy roots were treated with methyl jasmonate (MJ). From HPLC analysis, no peak for Rg3 was observed in the controls. However, Rg3 did accumulate in hairy roots that were MJ-treated for 7?days. Rg3 content was 0.42?mg/g (dry weight). To gain more insight into the effects of MJ on UDP-glucosyltransferase (UGT) activity, we attempted to evaluate ginsenoside Rg3 biosynthesis by UGT. A new peak for putative Rg3 was observed, which was confirmed by LC-MS/MS analysis. Our findings indicate that the proteins extracted from our hairy root lines can catalyze Rg3 from Rh2. This suggests that our ginseng hairy root lines possess Rg3 biosynthesis capacity. 相似文献
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To elucidate the bacterial diversity in biofilms formed on a condenser tube from a nuclear power plant, 16S rRNA gene sequences were examined using a PCR-cloning-sequencing approach. Twelve operational taxonomic units were retrieved in the clone library, and the estimated species richness was low (13.2). Most of the clones (94.7%) were affiliated with α-Proteobacteria; Planctomycetes and γ-Proteobacteria were much rarer. Interestingly, except for one clone belonging to Pseudoalteromonas, most of the sequences displayed sequence similarities <97% of those of the closest type strains. Based on 16S rRNA phylogenetic analysis, most bacteria were assigned to novel taxa above the species level. The low species richness and unusual bacterial composition may be attributable to selective pressure from chlorine in the cooling water. To prevent or control bacterial biofilms in cooling circuits, additional studies of the physiology and ecology of these species will be essential. 相似文献
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Daisuke Takahashi Yasuaki Hiromasa Yunjeong Kim Asokan Anbanandam Xiaolan Yao Kyeong‐Ok Chang Om Prakash 《Protein science : a publication of the Protein Society》2013,22(3):347-357
Norovirus protease is an essential enzyme for proteolytic maturation of norovirus nonstructural proteins and has been implicated as a potential target for antiviral drug development. Although X‐ray structural studies of the protease give us wealth of structural information including interactions of the protease with its substrate and dimeric overall structure, the role of protein dynamics in the substrate recognition and the biological relevance of the protease dimer remain unclear. Here we determined the solution NMR structure of the 3C‐like protease from Norwalk virus (NV 3CLpro), a prototype strain of norovirus, and analyzed its backbone dynamics and hydrodynamic behavior in solution. 15N spin relaxation and analytical ultracentrifugation analyses demonstrate that NV 3CLpro is predominantly a monomer in solution. Solution structure of NV 3CLpro shows significant structural variation in C‐terminal domain compared with crystal structures and among lower energy structure ensembles. Also, 15N spin relaxation and Carr–Purcell–Meiboom–Gill (CPMG)‐based relaxation dispersion analyses reveal the dynamic properties of residues in the C‐terminal domain over a wide range of timescales. In particular, the long loop spanning residues T123–G133 show fast motion (ps‐ns), and the residues in the bII–cII region forming the large hydrophobic pocket (S2 site) undergo conformational exchanges on slower timescales (μs–ms), suggesting their important role in substrate recognition. 相似文献