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151.
The effect of phenolic compounds on hydrothermal oxidation of cellulose was studied using a batch reactor at 300 degrees C with H(2)O(2) as oxidant. Intermediate products, as well as the yields of acetic acid produced in the oxidation of cellulose, phenolic compounds, and cellulose-phenolic compound mixtures were examined. Phenolic compounds used were phenol, 1,4-benzenediol, 2-methoxy-4-methylphenol, and 2,6-di-tert-butyl-4-methylphenol. In the case of oxidation of cellulose-phenolic compound mixtures, (1) formic acid, a basic oxidation product from carbohydrates, decreased considerably, (2) 5-hydroxymethyl-2-furaldehyde and 2-furaldehyde, acid-catalyzed dehydration products from carbohydrates, appeared, and (3) the yield of acetic acid increased compared to that in the oxidation of cellulose. From these results, phenolic compounds seem to inhibit the oxidation of cellulose under hydrothermal conditions. The inhibition of the oxidation of cellulose by phenolic compounds seems to be related closer to the stability of phenolic compounds under oxidation conditions rather than the ease to remove phenolic hydrogen on the OH group.  相似文献   
152.
Cantor coding provides an information coding scheme for temporal sequences of events. In the hippocampal CA3–CA1 network, Cantor coding-like mechanism was observed in pyramidal neurons and the relationship between input pattern and recorded responses could be described as an iterated function system. However, detailed physiological properties of the system in CA1 remain unclear. Here, we performed a detailed analysis of the properties of the system related to the physiological basis of learning and memory. First, we investigated whether the system could be simply based on a series of on–off responses of excitatory postsynaptic potential (EPSP) amplitudes. We applied a series of three spatially distinct input patterns with similar EPSP peak amplitudes. The membrane responses showed significant differences in spatial clustering properties related to the iterated function system. These results suggest that existence of some factors, which do not simply depend on a series of on–off responses but on spatial patterns in the system. Second, to confirm whether the system is dependent on the interval of sequential input, we applied spatiotemporal sequential inputs at several intervals. The optimal interval was 30 ms, similar to the physiological input from CA3 to CA1. Third, we analyzed the inhibitory network dependency of the system. After GABAA receptor blocker (gabazine) application, quality of code discrimination in the system was lower under subthreshold conditions and higher under suprathreshold conditions. These results suggest that the inhibitory network increase the difference between the responses under sub- and suprathreshold conditions. In summary, Cantor coding-like iterated function system appears to be suitable for information expression in relation to learning and memory in CA1 network.  相似文献   
153.

Objectives

Progressive cognitive decline is a characteristic hallmark of AD. It is important to identify prognostic markers to improve patient care and long-term planning. We aimed to identify the characteristics of disease progression in AD patients, focusing on cognitive decline and its related factors.

Methods

Clinically diagnosed AD patients in a memory clinic were followed. The mini–mental state examination (MMSE) and a battery of other neuropsychological tests were performed to assess the rate of cognitive decline and to analyze the related factors.

Results

A total of 165 AD patients were analyzed for cognitive changes. The MMSE scores declined at a rate of 1.52 points per year. Most neuropsychological test scores deteriorated significantly over time. Younger and early-onset AD patients deteriorated more rapidly than older and late-onset patients in global cognition and executive function. Men declined faster in memory but slower in attention than women. Higher education was associated with more rapid deterioration in visuo-spatial ability. Family history, hypertension and cerebral vascular disease were also associated with disease progression.

Conclusion

Attention, executive and visuo-spatial functions deteriorate at faster rates than other cognitive functions in AD patients. Age and age at onset were the main factors that associated with deterioration.  相似文献   
154.
Renal fibrosis is responsible for progressive renal diseases that cause chronic renal failure. Sfrp1 (secreted Frizzled-related protein 1) is highly expressed in kidney, although little is known about connection between the protein and renal diseases. Here, we focused on Sfrp1 to investigate its roles in renal fibrosis using a mouse model of unilateral ureteral obstruction (UUO). In wild-type mice, the expression of Sfrp1 protein was markedly increased after UUO. The kidneys from Sfrp1 knock-out mice showed significant increase in expression of myofibrobast markers, α-smooth muscle actin (αSMA). Sfrp1 deficiency also increased protein levels of the fibroblast genes, vimentin, and decreased those of the epithelial genes, E-cadherin, indicated that enhanced epithelial-to-mesenchymal transition. There was no difference in the levels of canonical Wnt signaling; rather, the levels of phosphorylated c-Jun and JNK were more increased in the Sfrp1−/− obstructed kidney. Moreover, the apoptotic cell population was significantly elevated in the obstructed kidneys from Sfrp1−/− mice following UUO but was slightly increased in those from wild-type mice. These results indicate that Sfrp1 is required for inhibition of renal damage through the non-canonical Wnt/PCP pathway.  相似文献   
155.
Lysophosphatidic acid (LPA) receptors belong to G protein-coupled transmembrane receptors and mediate a variety of cellular responses through the binding of LPA. So far, six types of LPA receptors (LPA receptor-1 (LPA?) to LPA?) have been identified. Recently, it has been demonstrated that each LPA receptor has opposite effects on malignant property of cancer cells. In this study, to evaluate an involvement of LPA receptors on angiogenic process in mammary tumor cells, we generated Lpar1- and Lpar3-expressing (FM3A-a1 and FM3A-a3A9, respectively) cells from FM3A cells, and investigated the effects on cell proliferation and migration abilities of endothelial F-2 cells by those cells. In Vegf-A and Vegf-C genes, FM3A-a1 cells indicated high expression and FM3A-a3A9 cells showed low expression, compared with control cells. When F-2 cells were cultured with a supernatant from FM3A-a1 cells, the cell growth rate and migration ability of F-2 cells was significantly higher than control cells. By contrast, a supernatant from FM3A-a3A9 cells significantly inhibited those abilities of F-2 cells. These results suggest that LPA? and LPA? may play opposite roles on the regulation of endothelial cells in mouse mammary tumor FM3A cells.  相似文献   
156.
Using lead citrate as a capture reagent and adenylate-(beta, gamma-methylene) diphosphate (AMP-PCP) as a substrate, we localized adenylate cyclase activity on the non-ruffled border plasma membrane of approximately half of the osteoclasts on trabecular bone surfaces in the tibial metaphyses of chickens fed a low (0.3%)-calcium diet. The enzyme was not detectable in osteoclasts when chickens were fed a normal calcium diet. Activity was observed on the entire plasma membrane of detached osteoclasts that were situated between osteoblasts on the bone surface and blood vessels in the marrow cavity. Detection of activity on detached osteoclasts required the presence of an activator, implying lower levels in these cells than in those with ruffled borders. Staining was greater on the lateral sides of osteoblasts and osteoclasts when they were in contact with each other. Reaction specificity was indicated by the demonstration of stimulation by forskolin, guanylate-(beta, gamma-methylene) diphosphate (GMP-PCP), dimethylsulfoxide, and NaF, inhibition by alloxan and 2',5'-dideoxyadenosine, and absence of activity when sections were incubated in substrate-free medium or when GMP-PCP replaced AMP-PCP as a substrate. The finding of adenylate cyclase in osteoclast plasma membrane provides structural evidence that the adenylate cyclase-cyclic AMP system has a role in regulation of osteoclast cell function. The low-calcium diet appears to have resulted in increased amounts of adenylate cyclase in osteoclasts.  相似文献   
157.
Tomato gray mold (Botrytis cinerea Pers.) is a common disease worldwide, and often causes serious production loss by infecting leaves, stems, flowers and fruits. Presently, no resistant cultivars are available. To find new breeding materials for gray mold resistance, assessment for resistance of the leaflet and stem in six tomato cultivars, 44 wild tomato accessions and a Solanum lycopersicoides accession was performed. Although no correlation was observed (r=−0.127ns) between resistance of the leaflet and the stem, L. peruvianum LA2745, L. hirsutum LA2314 and L. pimpinellifolium LA1246 showed high resistance both in the leaflet and in the stem. Particularly, in the leaves of LA2745, no lesions were observed even more than two weeks after the inoculation with conidia, and F1s between a cultivated tomato and LA2745 also showed high resistance as observed in LA2745. From these results, LA2745 is thought to be a promising material for breeding gray-mold resistant cultivars.  相似文献   
158.
Peptidyl-prolyl cis/trans isomerase NIMA-interacting 1 (Pin1) is a unique enzyme that associates with the pSer/Thr-Pro motif and catalyzes cis-trans isomerization. We identified Pin1 in the immunoprecipitates of overexpressed IRS-1 with myc and FLAG tags in mouse livers and confirmed the association between IRS-1 and Pin1 by not only overexpression experiments but also endogenously in the mouse liver. The analysis using deletion- and point-mutated Pin1 and IRS-1 constructs revealed the WW domain located in the N terminus of Pin1 and Ser-434 in the SAIN (Shc and IRS-1 NPXY binding) domain of IRS-1 to be involved in their association. Subsequently, we investigated the role of Pin1 in IRS-1 mediation of insulin signaling. The overexpression of Pin1 in HepG2 cells markedly enhanced insulin-induced IRS-1 phosphorylation and its downstream events: phosphatidylinositol 3-kinase binding with IRS-1 and Akt phosphorylation. In contrast, the treatment of HepG2 cells with Pin1 siRNA or the Pin1 inhibitor Juglone suppressed these events. In good agreement with these in vitro data, Pin1 knock-out mice exhibited impaired insulin signaling with glucose intolerance, whereas adenoviral gene transfer of Pin1 into the ob/ob mouse liver mostly normalized insulin signaling and restored glucose tolerance. In addition, it was also demonstrated that Pin1 plays a critical role in adipose differentiation, making Pin1 knock-out mice resistant to diet-induced obesity. Importantly, Pin1 expression was shown to be up-regulated in accordance with nutrient conditions such as food intake or a high-fat diet. Taken together, these observations indicate that Pin1 binds to IRS-1 and thereby markedly enhances insulin action, essential for adipogenesis.  相似文献   
159.
A linkage map of expressed sequence tag (EST)-based markers in radish (Raphanus sativus L.) was constructed using a low-cost and high-efficiency single-nucleotide polymorphism (SNP) genotyping method named multiplex polymerase chain reaction–mixed probe dot-blot analysis developed in this study. Seven hundred and forty-six SNP markers derived from EST sequences of R. sativus were assigned to nine linkage groups with a total length of 806.7 cM. By BLASTN, 726 markers were found to have homologous genes in Arabidopsis thaliana, and 72 syntenic regions, which have great potential for utilizing genomic information of the model species A. thaliana in basic and applied genetics of R. sativus, were identified. By construction and analysis of the genome structures of R. sativus based on the 24 genomic blocks within the Brassicaceae ancestral karyotype, 23 of the 24 genomic blocks were detected in the genome of R. sativus, and half of them were found to be triplicated. Comparison of the genome structure of R. sativus with those of the A, B, and C genomes of Brassica species and that of Sinapis alba L. revealed extensive chromosome homoeology among Brassiceae species, which would facilitate transfer of the genomic information from one Brassiceae species to another.  相似文献   
160.
Aims: Extracellular polymeric substances (EPS) are an important component of microbial biofilms, and it is becoming increasingly apparent that extracellular DNA (eDNA) has a functional role in EPS. This study characterizes the eDNA extracted from the novel activated sludge biofilm process of aerobic granules. Methods and Results: Exposing the sludge to cation exchange resin (CER) was used for the extraction of eDNA and intracellular DNA (iDNA) from aerobic granules. This was optimized for eDNA yield while causing minimal cell lysis. We then compared the DNA composition of these extractions using randomly amplified polymorphic DNA (RAPD) fingerprinting and PCR‐based denaturing gradient‐gel electrophoresis (DGGE). Upon the analysis of the genomic DNA and the 16S rRNA genes, differences were detected between the sludge biofilm eDNA and iDNA. Conclusions: Different bacteria within the biofilm disproportionally release DNA into the EPS matrix of the biofilm. Significance and Impact of the Study: The findings further the idea that eDNA has a functional role in the biofilm state, which is an important conceptual information for industrial application of biofilms.  相似文献   
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