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31.
Yu Yokoyama Masaki Tanito Koji Nitta Maki Katai Yasushi Kitaoka Kazuko Omodaka Satoru Tsuda Toshiaki Nakagawa Toru Nakazawa 《PloS one》2014,9(6)
PurposeThe Glaucoma Stereo Analysis Study (GSAS), a cross sectional multicenter collaborative study, used a stereo fundus camera to assess various morphological parameters of the optic nerve head (ONH) in glaucoma patients and investigated the relationships between these parameters and patient characteristics.ResultsPatient characteristics included refractive error of −3.38±3.75 diopters, intraocular pressure (IOP) of 13.6±2.6 mmHg, and visual field mean deviation (MD) of −4.71±3.26 dB. Representative ONH parameters included a horizontal disc width of 1.66±0.28 mm, vertical disc width of 1.86±0.23 mm, disc area of 2.42±0.63 mm2, cup area of 1.45±0.57 mm2, and cup volume of 0.31±0.22 mm3. Correlation analysis revealed significant negative associations between vertical cup-to-disc ratio (0.82±0.08) and MD (r = −0.40, P<0.01) and between disc tilt angle (10.5±12.5 degrees) and refractive error (r = −0.36, P<0.01). Seventy-five percent of the eyes had a positive value for rim decentering (0.30±0.42), indicating that rim thinning manifested more often as an inferior lesion than a superior lesion.ConclusionWe used stereoscopic analysis to establish a database of ONH parameters, which may facilitate future studies of glaucomatous changes in ONH morphology. 相似文献
32.
Keiichi Nitta Chikako Takura Isao Yamamoto Yuzuru Yamamoto Junzo Imai Saburo Yamatodani 《Bioscience, biotechnology, and biochemistry》2013,77(12):813-827
The chemical structure of oospolactone which is the metabolic product of Oospora astringenes was confirmed by the synthetical approach. 相似文献
33.
Sato I Morihira K Inami H Kubota H Morokata T Suzuki K Iura Y Nitta A Imaoka T Takahashi T Takeuchi M Ohta M Tsukamoto S 《Bioorganic & medicinal chemistry》2008,16(18):8607-8618
In our previous study on discovering novel types of CCR3 antagonists, we found a fluoronaphthalene derivative (1) that exhibited potent CCR3 inhibitory activity with an IC(50) value of 20 nM. However, compound 1 also inhibited human cytochrome P450 2D6 (CYP2D6) with an IC(50) value of 400 nM. In order to reduce its CYP2D6 inhibitory activity, we performed further systematic structural modifications on 1. In particular, we focused on reducing the number of lipophilic moieties in the biphenyl part of 1, using ClogD(7.4) values as the reference index of lipophilicity. This research led to the identification of N-{(3-exo)-8-[(6-fluoro-2-naphthyl)methyl]-8-azabicyclo[3.2.1]oct-3-yl}-3-(piperidin-1-ylcarbonyl)isonicotinamide 1-oxide (30) which showed comparable CCR3 inhibitory activity (IC(50)=23 nM) with much reduced CYP2D6 inhibitory activity (IC(50)=29,000 nM) compared with 1. 相似文献
34.
Takashi Kitagawa Shingo Kimura Hideaki Nakata Harumi Yamada Akira Nitta Yoshikazu Sasai Hideharu Sasaki 《Environmental Biology of Fishes》2009,84(2):193-196
The habitat and movements of a Pacific bluefin tuna were investigated by reanalyzing archival tag data with sea surface temperature
data. During its trans-Pacific migration to the eastern Pacific, the fish took a direct path and primarily utilized waters,
in the Subarctic Frontal Zone (SFZ). Mean ambient temperature during the trans-Pacific migration was 14.5 ± 2.9 (°C ± SD),
which is significantly colder than the waters typically inhabited by bluefin tuna in their primary feeding grounds in the
western and eastern Pacific (17.6 ± 2.1). The fish moved rapidly through the colder water, and the heat produced during swimming
and the thermoconservation ability of bluefin tuna likely enabled it to migrate through the cold waters of the SFZ. 相似文献
35.
Tetsuro Tamaki Yoshiyasu Uchiyama Yoshinori Okada Kayoko Tono Masahiro Nitta Akio Hoshi Akira Akatsuka 《Histochemistry and cell biology》2009,132(1):59-70
Tissue inflammation and multiple cellular responses in the compensatory enlarged plantaris (OP Plt) muscle induced by surgical
ablation of synergistic muscles (soleus and gastrocnemius) were followed over 10 weeks after surgery. Contralateral surgery
was performed in adult Wistar male rats. Cellular responses in muscle fibers, blood vessels and nerve fibers were analyzed
by immunohistochemistry and electron microscopy. Severe muscle fiber damage and disappearance of capillaries associated with
apparent tissue edema were observed in the peripheral portion of OP Plt muscles during the first week, whereas central portions
were relatively preserved. Marked cell activation/proliferation was also mainly observed in peripheral portions. Similarly,
activated myogenic cells were seen not only inside but also outside of muscle fibers. The former were likely satellite cells
and the latter may be interstitial myogenic cells. One week after surgery, small muscle fibers, small arteries and capillaries
and several branched-muscle fibers were evident in the periphery, thus indicating new muscle fiber and blood vessel formation.
Proliferating cells were also detected in the nerve bundles in the Schwann cell position. These results indicate that the
compensatory stimulated/enlarged muscle is a suitable model for analyzing multiple physiological cellular responses in muscle–nerve–blood
vessel units under continuous stretch stimulation.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
36.
Characterization of Fusarium oxysporum β-1,6-Galactanase, an Enzyme That Hydrolyzes Larch Wood Arabinogalactan 下载免费PDF全文
Tatsuji Sakamoto Yuya Taniguchi Shiho Suzuki Hideshi Ihara Haruhiko Kawasaki 《Applied microbiology》2007,73(9):3109-3112
A type II arabinogalactan-degrading enzyme (FoGal1) was purified from Fusarium oxysporum 12S, and the corresponding cDNA was isolated. FoGal1 had high similarity to enzymes of glycoside hydrolase family 5. Treatment of larch wood arabinogalactan with the recombinant enzyme indicated that FoGal1 is a β-1,6-galactanase that preferentially debranches β-1,6-galactobiose from the substrate. 相似文献
37.
Nobuyuki Kawasaki Kazuhiro Komatsu Ayato Kohzu Noriko Tomioka Ryuichiro Shinohara Takayuki Satou Fumiko Nara Watanabe Yuya Tada Koji Hamasaki M. R. M. Kushairi Akio Imai 《Applied and environmental microbiology》2013,79(23):7160-7168
Incubation experiments using filtered waters from Lake Kasumigaura were conducted to examine bacterial contribution to a dissolved organic carbon (DOC) pool. Bacterial abundance, bacterial production, concentrations of DOC, total dissolved amino acids (TDAA), and total dissolved neutral sugars (TDNS) were monitored during the experiments. Bacterial production during the first few days was very high (20 to 35 μg C liter−1 day−1), accounting for 40 to 70% of primary production. The total bacterial production accounted for 34 to 55% of the DOC loss during the experiment, indicating high bacterial activities in Lake Kasumigaura. The DOC degradation was only 12 to 15%, whereas the degradation of TDAA and TDNS ranged from 30 to 50%, suggesting the preferential usage of TDAA and TDNS. The contribution of bacterially derived carbon to a DOC pool in Lake Kasumigaura was estimated using d-amino acids as bacterial biomarkers and accounted for 30 to 50% of the lake DOC. These values were much higher than those estimated for the open ocean (20 to 30%). The ratio of bacterially derived carbon to bulk carbon increased slightly with time, suggesting that the bacterially derived carbon is more resistant to microbial degradation than bulk carbon. This is the first study to estimate the bacterial contribution to a DOC pool in freshwater environments. These results indicate that bacteria play even more important roles in carbon cycles in freshwater environments than in open oceans and also suggests that recent increases in recalcitrant DOC in various lakes could be attributed to bacterially derived carbon. The potential differences in bacterial contributions to dissolved organic matter (DOM) between freshwater and marine environments are discussed. 相似文献
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40.
Isaka K Suwa Y Kimura Y Yamagishi T Sumino T Tsuneda S 《Applied microbiology and biotechnology》2008,81(2):379-385
Methanol inhibition of anaerobic ammonium oxidation (anammox) activity was characterized. An enrichment culture entrapped
in a polyethylene glycol gel carrier was designed for practical uses of wastewater treatment. Batch experiments demonstrated
that anammox activity decreased with increases in methanol concentration, and relative activity reached to 29% of the maximum
when 5 mM methanol was added. Also, batch experiments were conducted using anammox sludge without immobilization. Anammox
activity was evaluated by quantifying 14N15N (29N) emission by combined gas chromatography-quadrupole mass spectrometry, and the anammox activity was found to be almost as
sensitive to methanol as in the earlier trials in which gel carriers were used. These results indicated that methanol inhibition
was less severe than previous studies. When methanol was added in the influent of continuous feeding system, relative activity
was decreased to 46% after 80 h. Although the addition was halted, afterwards the anammox activity was not resumed in another
19 days of cultivation, suggesting that methanol inhibition to anammox activity was irreversible. It is notable that methanol
inhibition was not observed if anammox activity was quiescent when substrate for anammox was not supplied. These results suggest
that methanol itself is not inhibitory and may not directly inhibit the anammox activity. 相似文献