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51.
52.
Accumulating data indicates that certain microRNAs (miRNAs or miRs) are differently expressed in samples of tumors and paired non-tumorous samples taken from the same patients with colorectal tumors. We examined the expression of onco-related miRNAs in 131 sporadic exophytic adenomas or early cancers and in 52 sporadic flat elevated adenomas or early cancers to clarify the relationship between the expression of the miRNAs and the endoscopic morphological appearance of the colorectal tumors. The expression levels of miR-143, -145, and -34a were significantly reduced in most of the exophytic tumors compared with those in the flat elevated ones. In type 2 cancers, the miRNA expression profile was very similar to that of the exophytic tumors. The expression levels of miR-7 and -21 were significantly up-regulated in some flat elevated adenomas compared with those in exophytic adenomas. In contrast, in most of the miR-143 and -145 down-regulated cases of the adenoma-carcinoma sequence and in some of the de novo types of carcinoma, the up-regulation of oncogenic miR-7 and/or -21 contributed to the triggering mechanism leading to the carcinogenetic process. These findings indicated that the expression of onco-related miRNA was associated with the morphological appearance of colorectal tumors.  相似文献   
53.
Effects of the clumping of bacterial spores on their heat resistance as a result of heat treatment were investigated. Spore suspensions of Bacillus cereus, Bacillus coagulans and Bacillus licheniformis were heated at 85 degrees C. Survivor curves of the three strains showed tailing in all treatments after 30 min. As the treatment time increased, the formation of spore clumps increased in all strains after 20 min. Relative hydrophobicity of the spore surface increased as a result of heat treatment. The effect of spore concentration on the inactivation of the B. licheniformis spores was investigated, and surviving curves showed no tailing below a concentration of 4.9 log CFU/ml.  相似文献   
54.
Rhodococcus jostii RHA1 accumulates chlorobenzoates (CBA) during the degradation of polychlorinated biphenyls (PCBs). CBA degradation is considered one of the rate-limiting steps in the complete degradation of PCBs. To reduce the accumulation of CBAs, the upper pathway enzyme genes for PCB degradation of RHA1 were introduced into a CBA-degrading bacterium, Burkholderia sp. NK8. The resulting recombinant strain exhibited no biphenyl 2,3-dioxygenase (BphA) activity encoded by bphAaAbAcAd genes, which encode the large and small subunits of the terminal oxygenase component and the ferredoxin and reductase subunits responsible for electron transfer from NADH to the large subunit. The remaining enzyme genes involved in the transformation of biphenyl to benzoate, bphB2C1D1, which encode dehydrogenase, ring-cleavage dioxygenase and hydrolase, conferred activities to NK8. To obtain the BphA activity of RHA1 in NK8, sets of BphA genes were constructed by combining the bphAaAbAcAd genes of RHA1 and bphA3A4 of Pseudomonas pseudoalcaligenes KF707, encoding the ferredoxin and reductase subunits. Hybrid derivatives of BphA containing the KF707 bphA3 conferred BphA activity to NK8, and a derivative containing the RHA1 bphAaAb and KF707 bphA3A4 genes exhibited the highest BphA activity. A plasmid containing the RHA1 bphAaAb and KF707 bphA3A4 genes plus the RHA1 bphB2C1D1 genes was constructed and introduced into NK8. The resulting recombinant strain efficiently degraded 2-, 3- and 4-chlorobiphenyls with an apparent reduction in CBA accumulation in comparison to the recombinant mutant strain, which had an insertion in the cbeA gene to inactivate CBA dioxygenase.  相似文献   
55.
Offshore wind simulations were performed with the Weather Research and Forecasting (WRF) model driven by three different sea surface temperature (SST) datasets for Japanese coastal waters to investigate the effect of the SST accuracies on offshore wind simulations. First, the National Centers for Environmental Prediction Final analysis (FNL) (1° × 1° grid resolution) and the Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) (0.05° × 0.05° grid resolution) datasets were compared with in situ measurements. The results show a decrease in accuracy of these datasets toward the coast from the open ocean. Aiming at an improved accuracy of SST data, we developed a new high‐resolution SST dataset (0.02° × 0.02° grid resolution). The new dataset referred to as MOSST is based on the Moderate Resolution Imaging Spectroradiometer (MODIS) product, provided by the Japan Aerospace Exploration Agency (JAXA). MOSST was confirmed to be more accurate than FNL and OSTIA for the coastal waters. Then, WRF simulations were carried out for 1 year with a 2 km grid resolution and by using the FNL, OSTIA and MOSST datasets. The use of the OSTIA dataset for a WRF simulation was found to improve the accuracy when compared with the FNL dataset, and further improvement was obtained when the MOSST dataset was applied. The sensitivity of wind speed and wind energy density to SST is also discussed. We conclude that the use of an accurate SST is a key factor not only for realistic offshore wind simulations near the surface but also for accurate wind resource assessments at the hub height of wind turbines. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
56.
This paper describes an unusual behavior detection system based on an omnidirectional vision sensor, as one of the important elements in realizing “Sensing and Robotic Support Rooms” for elderly people. Such support rooms are expected to be further developed in the future with advanced abilities to automatically recognize elderly people's actions and behavior patterns, to detect unusual patterns by using sensors, and to support their daily motions by using robotic manipulator control systems. The proposed monitoring system using an omnidirectional vision sensor automatically learns daily behavior patterns and detects unusual behavior patterns and actions by using the Bayesian network approach. The Bayesian network is constructed by using image feature values such as area and center‐of‐gravity values extracted from a captured image sequence, and the respective behavior patterns are represented as conditional probabilities. Unusual behavior patterns can be automatically detected on the basis of the low generation probability values. Experiments based on the investigation of elderly people's typical daily behavior patterns have shown the effectiveness of the proposed system. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 172(3): 42–51, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20990  相似文献   
57.
Familial male-limited precocious puberty (FMPP) is a form of luteinizing hormone-releasing hormone (LHRH)-independent isosexual precocious puberty caused by gain-of-function mutations of the luteinizing hormone/chorionic gonadotropin receptor (hLHR). The most common mutation is 1733 A>G, which causes substitution of Asp-578 by Gly. In this study, a male infant presented at the age of 20 months with accelerated sexual development was analyzed for the presence of activating mutations of the hLHR. Analysis of exon 11 of the hLHR gene by genomic polymerase chain reaction (PCR), asymmetric PCR, and dideoxy sequencing identified a single base substitution, 1734 T>A, which led to the replacement of Asp-578 by Glu. The same mutation was found in the mother. Expression of the mutated hLHR in HEK 293 cells demonstrated elevated basal levels of intracellular cAMP in the transfected cells confirming the constitutive activating nature of the mutated hLHR. A possible genotype-phenotype relationship of the hLHR mutations was examined by a comparison of the in vitro activities of the hLHRs carrying the Asp578Gly, Asp578Tyr, Asp578Trp, and Asp578Glu mutations in HEK 293 cells. A positive correlation between the size of the substituting amino acid and the basal level of intracellular cAMP of cells expressing the mutated receptor was demonstrated.  相似文献   
58.
Ba β-alumina films were prepared by laser chemical vapor deposition. Mostly single-phase Ba β-alumina films were obtained at 1125–1200 K and for an Al/Ba molar ratio of 12.4–16.6. BaAl2O4 and α-Al2O3 were codeposited with Ba β-alumina under Ba- and Al-rich conditions, respectively. The Ba β-alumina films consisted of hexagonal grains, and the (1 1 0)-oriented Ba β-alumina films had a fin-like columnar structure. The highest deposition rate reached 120 μm h?1 at around 1200 K. A thin layer of Ba-rich superstructure was formed on the surface of the (1 1 0)-oriented columnar grains.  相似文献   
59.
1. The effects of secreted forms of beta-amyloid-precursor proteins (APP(S)s) on the intracellular Ca2+ concentration ([Ca2+]i) were investigated in rat cultured hippocampal neurones. APP695S, a secretory form of APP695, attenuated the increase in [Ca2+]i evoked by glutamate. In addition, APP695S itself evoked an increase in [Ca2+]i in 1 or 2 day-cultured hippocampal cells, but not in 7 to 13 day-cultured cells. 2. Eighty-one percent of neurones which were immunocytochemically positive for microtubule-associated protein 2 responded to APP695S with an increase in [Ca2+]i. 3. APP695S induced a transient rise in [Ca2+]i even in the absence of extracellular Ca2+ and produced an elevation in inositol-1,4,5-trisphosphate (IP3) in a concentration-dependent manner from 100 to 500 ng ml(-1). In the presence of extracellular Ca2+, APP695S caused a transient rise in [Ca2+]i followed by a sustained phase at high [Ca2+]i, suggesting Ca2+ entry from the extracellular space. 4. The [Ca2+]i elevation was mimicked by amino terminal peptides of APPs, but not by carboxy terminal peptides. 5. These results taken together suggest that APP695S induces an increase in [Ca2+]i in hippocampal neurones through an IP3-dependent mechanism that changes according to the stage of development.  相似文献   
60.
Electrospray ionization (ESI) Fourier transform ion cyclotron resonance (FTICR) mass spectrometry has been used to characterize heterotetrameric corynebacterial sarcosine oxidase. By using a conventional quadrupole mass spectrometer, no spectra for the intact complex could be obtained (i.e., electrospraying protein at neutral pH), but spectra showing the four protein subunits were obtained when electrospraying from acidic solution. Initial low resolution ESI-FTICR mass spectra of the intact heterotetramer revealed a typical narrow charge state distribution in the range 6000 < m/z < 9000, consistent with retention of a compact structure in the gas phase, and gave a mass measurement about 1000 u higher than predicted. Efficient in-trap clean up, based upon low energy collisionally induced dissociation of adducts, allowed significant improvement in mass measurement accuracy. The present results represent the largest heteromultimeric protein complex successfully analyzed using FTICR mass spectrometry, and clearly illustrate the importance of sample clean up methods for large molecule characterization.  相似文献   
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