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991.
Syeda Mehpara Farhat Aamra Mahboob Ghazala Iqbal Touqeer Ahmed 《Biological trace element research》2017,177(1):115-121
Aluminum is associated with etiology of many neurodegenerative diseases specially Alzheimer’s disease. Chronic exposure to aluminum via drinking water results in aluminum deposition in the brain that leads to cognitive deficits. The study aimed to determine the effects of aluminum on cholinergic biomarkers, i.e., acetylcholine level, free choline level, and choline acetyltransferase gene expression, and how cholinergic deficit affects novel object recognition and sociability in mice. Mice were treated with AlCl3 (250 mg/kg). Acetylcholine level, free choline level, and choline acetyltransferase gene expression were determined in cortex, hippocampus, and amygdala. The mice were subjected to behavior tests (novel object recognition and social novelty preference) to assess memory deficits. The acetylcholine level in cortex and hippocampus was significantly reduced in aluminum-treated animals, as compared to cortex and hippocampus of control animals. Acetylcholine level in amygdala of aluminum-treated animals remained unchanged. Free choline level in all the three brain parts was found unaltered in aluminum-treated mice. The novel object recognition memory was severely impaired in aluminum-treated mice, as compared to the control group. Similarly, animals treated with aluminum showed reduced sociability compared to the control mice group. Our study demonstrates that aluminum exposure via drinking water causes reduced acetylcholine synthesis in spite of normal free choline availability. This deficit is caused by reduced recycling of acetylcholine due to lower choline acetyltransferase level. This cholinergic hypofunction leads to cognitive and memory deficits. Moreover, hippocampus is the most affected brain part after aluminum intoxication. 相似文献
992.
Fontán-Lozano A López-Lluch G Delgado-García JM Navas P Carrión AM 《Molecular neurobiology》2008,38(2):167-177
Aging is associated with the decline of cognitive properties. This situation is magnified when neurodegenerative processes
associated with aging appear in human patients. Neuronal synaptic plasticity events underlie cognitive properties in the central
nervous system. Caloric restriction (CR; either a decrease in food intake or an intermittent fasting diet) can extend life
span and increase disease resistance. Recent studies have shown that CR can have profound effects on brain function and vulnerability
to injury and disease. Moreover, CR can stimulate the production of new neurons from stem cells (neurogenesis) and can enhance
synaptic plasticity, which modulate pain sensation, enhance cognitive function, and may increase the ability of the brain
to resist aging. The beneficial effects of CR appear to be the result of a cellular stress response stimulating the production
of proteins that enhance neuronal plasticity and resistance to oxidative and metabolic insults; they include neurotrophic
factors, neurotransmitter receptors, protein chaperones, and mitochondrial biosynthesis regulators. In this review, we will
present and discuss the effect of CR in synaptic processes underlying analgesia and cognitive improvement in healthy, sick,
and aging animals. We will also discuss the possible role of mitochondrial biogenesis induced by CR in regulation of neuronal
synaptic plasticity. 相似文献
993.
Roh SW Kim KH Nam YD Chang HW Kim MS Yoon JH Oh HM Bae JW 《Journal of microbiology (Seoul, Korea)》2008,46(5):525-529
A novel bacterium B9T was isolated from tidal flat sediment. Its morphology, physiology, biochemical features, and 16S rRNA gene sequence were
characterized. Colonies of this strain are yellow and the cells are Gram-negative, rod-shaped, and do not require NaCl for
growth. The 16S rRNA gene sequence similarity indicated that strain B9T is associated with the genus Lysobacter (≤ 97.2%), Xanthomonas (≤ 96.8%), Pseudomonas (≤ 96.7%), and Luteimonas (≤ 96.0%). However, within the phylogenetic tree, this novel strain shares a branching point with the species Luteimonas composti CC-YY255T (96.0%). The DNA-DNA hybridization experiments showed a DNA-DNA homology of 23.0% between strain B9T and Luteimonas mephitis B1953/27.1T. The G+C content of genomic DNA of the type strain is 64.7 mol% (SD, 1.1). The predominant fatty acids are iso-C11:0, iso-C15:0, iso-C16:0, iso-C17:0, iso-C17:0
ω9c, and iso-C11:0 3-OH. Combined analysis of the 16S rRNA gene sequences, fatty acid profile, and results from physiological and biochemical
tests indicated that there is genotypic and phenotypic differentiation of the isolate from other Luteimonas species. For these reasons, strain B9T was proposed as a novel species, named Luteimonas aestuarii. The type strain of the new species is B9T (= KCTC 22048T, DSM 19680T). 相似文献
994.
Molecular identification and dynamics of microbial communities in reactor treating organic household waste 总被引:1,自引:0,他引:1
Juliana Cardinali-Rezende Renan B. Debarry Luis F. D. B. Colturato Eduardo V. Carneiro Edmar Chartone-Souza Andrea M. A. Nascimento 《Applied microbiology and biotechnology》2009,84(4):777-789
The prokaryotic diversity associated with organic household waste (OHW), leachate (start-up inoculum), and mesophilic anaerobic
digestion processes in the degradation of OHW for 44 and 90 days was investigated using a culture-independent approach. Bacterial
and archaeal 16S rRNA and mcrA gene clone libraries were constructed from community DNA preparations. Bacterial clones were affiliated with 13 phyla, of
which Firmicutes, Proteobacteria, and Bacteroidetes were represented in all libraries, whereas Actinobacteria, Thermotogae, Lentisphaerae, Acidobacteria, Chloroflexi, Cyanobacteria, Synergistetes, Spirochaetes, Deferribacteres, and Deinococcus-Thermus were exclusively identified in a single library. Within the Archaea domain, the Euryarchaeota phylum was the only one represented. Corresponding sequences were associated with the following orders of hydrogenotrophic
methanogens: Methanomicrobiales (Methanoculleus genus) and Methanobacteriales (Methanosphaera and Methanobacterium genera). One archaeal clone was not affiliated with any order and may represent a novel taxon. Diversity indices showed greater
diversity of Bacteria when compared to methanogenic Archaea. 相似文献
995.
Analysis of trehalose-6-phosphate synthase (TPS) gene family suggests the formation of TPS complexes in rice 总被引:2,自引:0,他引:2
Trehalose-6-phosphate (T6P), an intermediate in the trehalose biosynthesis pathway, is emerging as an important regulator
of plant metabolism and development. T6P levels are potentially modulated by a group of trehalose-6-phosphate synthase (TPS)
and trehalose-6-phosphate phosphatase (TPP) homologues. In this study, we have isolated 11 TPS genes encoding proteins with both TPS and TPP domains, from rice. Functional complement assays performed in yeast tps1 and tps2 mutants, revealed that only OsTPS1 encodes an active TPS enzyme and no OsTPS protein possesses TPP activity. By using a yeast two-hybrid analysis, a complicated
interaction network occurred among OsTPS proteins, and the TPS domain might be essential for this interaction to occur. The
interaction between OsTPS1 and OsTPS8 in vivo was confirmed by bimolecular fluorescence complementation and coimmunoprecipitation
assays. Furthermore, our gel filtration assay showed that there may exist two forms of OsTPS1 (OsTPS1a and OsTPS1b) with different
elution profiles in rice. OsTPS1b was particularly cofractionated with OsTPS5 and OsTPS8 in the 360 kDa complex, while OsTPS1a
was predominantly incorporated into the complexes larger than 360 kDa. Collectively, these results suggest that OsTPS family members may form trehalose-6-phosphate synthase complexes and therefore potentially modify T6P levels to regulate
plant development. 相似文献
996.
Eduard Akhunov Charles Nicolet Jan Dvorak 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,119(3):507-517
Single nucleotide polymorphisms (SNPs) are indispensable in such applications as association mapping and construction of high-density
genetic maps. These applications usually require genotyping of thousands of SNPs in a large number of individuals. Although
a number of SNP genotyping assays are available, most of them are designed for SNP genotyping in diploid individuals. Here,
we demonstrate that the Illumina GoldenGate assay could be used for SNP genotyping of homozygous tetraploid and hexaploid
wheat lines. Genotyping reactions could be carried out directly on genomic DNA without the necessity of preliminary PCR amplification.
A total of 53 tetraploid and 38 hexaploid homozygous wheat lines were genotyped at 96 SNP loci. The genotyping error rate
estimated after removal of low-quality data was 0 and 1% for tetraploid and hexaploid wheat, respectively. Developed SNP genotyping
assays were shown to be useful for genotyping wheat cultivars. This study demonstrated that the GoldenGate assay is a very
efficient tool for high-throughput genotyping of polyploid wheat, opening new possibilities for the analysis of genetic variation
in wheat and dissection of genetic basis of complex traits using association mapping approach.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
997.
Miyamoto K Okunishi M Nukui E Tsuchiya T Kobayashi T Imada C Tsujibo H 《Archives of microbiology》2007,188(6):619-628
998.
Pectinase was immobilized on a sodium alginate support using glutaraldehyde and retained 66% activity. The optimal pH for
activity shifted from 3.0 to 3.5 after immobilization; however, the optimum temperature remained unchanged at 40°C. The immobilized
enzyme also had a higher thermal stability and reusability than the free enzyme, and retained 80% of initial activity after
11 batch reactions. 相似文献
999.
Ogawa S Tokumoto Y Miyake J Nagamune T 《In vitro cellular & developmental biology. Animal》2011,47(7):464-469
Induced pluripotent stem cells (iPSCs) prepared from somatic cells might become a novel therapeutic tool in regenerative medicine,
especially for the central nervous system (CNS). In this study, we attempted to induce O4-positive (O4+) oligodendrocytes from adult human fibroblast-derived iPSCs in vitro. We used two adult human iPSC cell lines, 201B7 and
253G1. 201B7 was induced by four-gene transduction (oct4, sox2, klf4, c-myc), and 253G1 was induced by three-gene transduction
(oct4, sox2, klf4). We treated these cells with two in vitro oligodendrocyte-directed differentiation protocols that were
optimized for human embryonic stem cells. One protocol used platelet-derived growth factor as the major mitogen for oligodendrocyte
lineage cells, and the other protocol used epidermal growth factor (EGF) as the mitogen. Although the differentiation efficiency
was low (less than 0.01%), we could induce O4+ oligodendrocytes from 253G1 cells using the EGF-dependent differentiation protocol. This is the first report of the in vitro
induction of oligodendrocytes differentiation from human iPSCs. 相似文献
1000.
Dennis Trolle Guangwei Zhu David Hamilton Liancong Luo Chris McBride Lu Zhang 《Hydrobiologia》2009,627(1):31-44
Distinct horizontal water column concentration gradients of nutrients and chlorophyll a (Chl a) occur within large, shallow, eutrophic Lake Taihu, China. Concentrations are high in the north, where some of the major
polluted tributaries enter the lake, and relatively low in the south, where macrophytes generally are abundant. It is not
clear, however, whether these water column concentration gradients are similarly reflected in spatial heterogeneity of nutrient
concentrations within the bottom sediments. The main objective of this study was therefore to test if horizontal and vertical
variations in the phosphorus and nitrogen content in bottom sediments of Lake Taihu are significantly related to (1) horizontal
variations in overlying water column nutrient concentrations and (2) other sediment geochemical constituents. We measured
the concentration of total phosphorus (TP) and total nitrogen (TN) in surficial sediments (0–2 cm) and TP, TN and Chl a concentrations in water column samples, collected from 32 sites in 2005. In 2006 sediment, TP, TN, carbon, iron and manganese
concentrations were measured vertically at 2 cm intervals, extending to a depth of approximately 20 cm, at an additional eight
sites. Linear correlation analysis revealed that surficial sediment TP concentrations across the 32 stations were related
significantly, though weakly, to annual mean water column concentrations of TP, TN as well as Chl a. Correlations of surficial sediment TN with water column variables were, however, not significant (P > 0.05). Amongst the geochemical variables tested, the vertical variability of sediment TP concentrations was most strongly
related to sediment manganese and carbon concentrations. A multiple stepwise linear regression revealed that the combination
of sediment manganese and carbon concentrations explained 91% of the horizontal variability in sediment TP concentrations
and 65% of the vertical variability.
Handling editor: Luigi Naselli-Flores 相似文献