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131.
Tomotaka Tanaka Hiroshi Yamagami Masafumi Ihara Rie Motoyama Kazuki Fukuma Tetsuya Miyagi Kazutaka Nishimura Kazunori Toyoda Kazuyuki Nagatsuka 《PloS one》2015,10(8)
Background
Seizure is a common complication after stroke (termed “post-stroke seizure,” PSS). Although many studies have assessed outcomes and risk factors of PSS, no reliable predictors are currently available to determine PSS recurrence. We compared baseline clinical characteristics and post-stroke treatment regimens between recurrent and non-recurrent PSS patients to identify factors predictive of recurrence.Methods
Consecutive PSS patients admitted to our stroke center between January 2011 and July 2013 were monitored until February 2014 (median 357 days; IQR, 160–552) and retrospectively evaluated for baseline clinical characteristics and PSS recurrence. Cumulative recurrence rates at 90, 180, and 360 days post-stroke were estimated by Kaplan—Meier analysis. Independent predictors of recurrent PSS were identified by Cox proportional-hazards analysis.Results
A total of 104 patients (71 men; mean age, 72.1 ± 11.2 years) were analyzed. PSS recurred in 31 patients (30%) during the follow-up. Factors significantly associated with PSS recurrence by log-rank analysis included previous PSS, valproic acid (VPA) monotherapy, polytherapy with antiepileptic drugs (AEDs), frontal cortical lesion, and higher modified Rankin Scale score at discharge (all p < 0.05). Independent predictors of recurrent PSS were age <74 years (HR 2.38, 95% CI 1.02–5.90), VPA monotherapy (HR 3.86, 95% CI 1.30–12.62), and convulsions on admission (HR 3.87, 95% CI 1.35–12.76).Conclusions
Approximately one-third of PSS patients experienced seizure recurrence within one year. The predictors of recurrent PSS were younger age, presence of convulsions and VPA monotherapy. Our findings should be interpreted cautiously in countries where monotherapy with second-generation AEDs has been approved because this study was conducted while second-generation AEDs had not been officially approved for monotherapy in Japan. 相似文献132.
Tomoyuki Watanabe Masao Saotome Mamoru Nobuhara Atsushi Sakamoto Tsuyoshi Urushida Hideki Katoh Hiroshi Satoh Makoto Funaki Hideharu Hayashi 《Experimental cell research》2014
Purpose
Evidence suggests an association between aberrant mitochondrial dynamics and cardiac diseases. Because myocardial metabolic deficiency caused by insulin resistance plays a crucial role in heart disease, we investigated the role of dynamin-related protein-1 (DRP1; a mitochondrial fission protein) in the pathogenesis of myocardial insulin resistance.Methods and Results
DRP1-expressing H9c2 myocytes, which had fragmented mitochondria with mitochondrial membrane potential (ΔΨm) depolarization, exhibited attenuated insulin signaling and 2-deoxy-d-glucose (2-DG) uptake, indicating insulin resistance. Treatment of the DRP1-expressing myocytes with Mn(III)tetrakis(1-methyl-4-pyridyl)porphyrin pentachloride (TMPyP) significantly improved insulin resistance and mitochondrial dysfunction. When myocytes were exposed to hydrogen peroxide (H2O2), they increased DRP1 expression and mitochondrial fragmentation, resulting in ΔΨm depolarization and insulin resistance. When DRP1 was suppressed by siRNA, H2O2-induced mitochondrial dysfunction and insulin resistance were restored. Our results suggest that a mutual enhancement between DRP1 and reactive oxygen species could induce mitochondrial dysfunction and myocardial insulin resistance. In palmitate-induced insulin-resistant myocytes, neither DRP1-suppression nor TMPyP restored the ΔΨm depolarization and impaired 2-DG uptake, however they improved insulin signaling.Conclusions
A mutual enhancement between DRP1 and ROS could promote mitochondrial dysfunction and inhibition of insulin signal transduction. However, other mechanisms, including lipid metabolite-induced mitochondrial dysfunction, may be involved in palmitate-induced insulin resistance. 相似文献133.
Yutaka Shibata Wataru Katoh Tomofumi Chiba Keisuke Namie Norikazu Ohnishi Jun Minagawa Hanayo Nakanishi Takumi Noguchi Hiroshi Fukumura 《BBA》2014
A novel cryogenic optical-microscope system was developed in which the objective lens is set inside of the cryostat adiabatic vacuum space. Being isolated from the sample when it was cooled, the objective lens was maintained at room temperature during the cryogenic measurement. Therefore, the authors were able to use a color-aberration corrected objective lens with a numerical aperture of 0.9. The lens is equipped with an air vent for compatibility to the vacuum. The theoretically expected spatial resolutions of 0.39 μm along the lateral direction and 1.3 μm along the axial direction were achieved by the developed system. The system was applied to the observations of non-uniform distributions of the photosystems in the cells of a green alga, Chlamydomonas reinhardtii, at 94 K. Gaussian decomposition analysis of the fluorescence spectra at all the pixels clearly demonstrated a non-uniform distribution of the two photosystems, as reflected in the variable ratios of the fluorescence intensities assigned to photosystem II and to those assigned to photosystem I. The system was also applied to the fluorescence spectroscopy of single isolated photosystem I complexes at 90 K. The fluorescence, assigned to be emitted from a single photosystem I trimer, showed an intermittent fluctuation called blinking, which is typical for a fluorescence signal from a single molecule. The vibronic fluorescence bands at around 790 nm were observed for single photosystem I trimers, suggesting that the color aberration is not serious up to the 800 nm spectral region. 相似文献
134.
Simultaneous polygyny of the gobiid fish Asterropteryx semipunctata in relation to mate availability
Nesting males of Asterropteryx semipunctata conducted spawning behavior with 2–6 females simultaneously. We carried out field observations on a rocky reef in Kagoshima,
Japan, to examine the hypotheses that large males will show multi-female spawning behavior because of their mating advantage,
and that simultaneous multi-female spawning will occur when the operational sex ratio (OSR; the ratio of receptive males to
receptive females) becomes female-biased. Contrary to our prediction, neither the total number of multi-female spawnings during
a spawning season nor mean number of spawning females at a time were correlated with nesting male sizes. This indicates that
larger males often did not conduct multi-female spawnings. As predicted, the incidence of multi-female spawning followed the
change in the OSR over time—as the OSR in the study area became biased toward females, the incidence of multi-female spawnings
gradually increased. Our results suggest that mate availability affects mating patterns in A. semipunctata. 相似文献
135.
Tetsu Yamane Masako Mitsumata Noriko Yamaguchi Tadao Nakazawa Kunio Mochizuki Tetsuo Kondo Tomonori Kawasaki Shin-ichi Murata Yoji Yoshida Ryohei Katoh 《Cell and tissue research》2010,340(3):471-479
Remodeling of endothelial basement membrane is important in atherogenesis. Since little is known about the actual relationship
between type IV collagen and matrix metalloprotease−2 (MMP-2) in endothelial cells (ECs) under shear stress by blood flow,
we performed quantitative analysis for type IV collagen and MMP-2 in ECs under high shear stress. The mRNA of type IV collagen
from ECs exposed to high shear stress (10 and 30 dyn/cm2) had a higher expression compared to ECs exposed to a static condition or low shear stress (3 dyn/cm2) (P < 0.01). 3H-proline uptake analysis and fluorography revealed a remarkable increase of type IV collagen under high shear stress (P < 0.01). In contrast, zymography revealed that exposing to high shear stress, however similar positivity was leveled in the
intracellular MMP-2 in the control and high shear stress-exposed ECs, reduced the secretion of MMP-2 in ECs. The results of
Northern blotting, gelatin zymography and monitoring the intracellular trafficking of GFP-labeled MMP-2 revealed that MMP-2
secretion by ECs was completely suppressed by high shear stress, but the intracellular mRNA expression, protein synthesis,
and transport of MMP-2 were not affected. In conclusion, we suggest that high shear stress up-regulates type IV collagen synthesis
and down-regulates MMP-2 secretion in ECs, which plays an important role in remodeling of the endothelial basement membrane
and may suppress atherogenesis. 相似文献
136.
Fusarium sp. BLB, which produces a strongly fibrinolytic enzyme, was isolated from plant leaf (Hibiscus). Fibrinolytic alkaline protease was purified from a culture filtrate of Fusarium sp. BLB by precipitation with (NH4)2SO4 and column chromatography with CM-Toyopearl 650M and Superdex 75. The purified enzyme was homogeneous on sodium dodecyl sulfate
polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weight was 27,000 by SDS-PAGE. Maximum activity of protease was
observed at pH 9.5 and 50°C. Purified protease was active between pH 2.5 and 11.5 and was found to be stable up to 50°C. The
enzyme derived from Fusarium sp. BLB is useful for thrombolytic therapy because this enzyme showed pH resistance. The activity was inhibited by diisopropylfluorophosphate
and phenylmethylsulfonyl fluoride. The N-terminal amino acid sequence of the enzyme showed a similarity to those of proteases
from Fusarium sp., Streptomyces griseus, Bos taurus bovine, Katsuwo pelamis digestive tract, and Lumbricus rubellus. 相似文献
137.
Keiichiro Ide Kazutaka Takahashi 《Journal of experimental marine biology and ecology》2007,340(1):70-79
Direct observations on foraging behaviour of scavenging lysianassid amphipods have been limited, and no previous study has examined the effect of food odour quantitatively on the behaviour. The present study recorded the swimming behaviour of the amphipod Scopelocheirus onagawae using videographic techniques before and after the introduction of food odour (amino acid solution). S. onagawae showed consistent nocturnal activity swimming at a high speed (16.8 cm s− 1) with an approximately straight trajectory in various directions before and after the introduction of odour in which the amino acid concentration was below the behavioural threshold concentration for this species (1.0 × 10− 7 mol l− 1). High speed multidirectional linear swimming is thought to be advantageous for these amphipods, enabling them to survey across a broad area. After the first encounter with the odour plume above the behavioural threshold concentration, the amphipods slowed down their swimming speed (ca. 9.7 cm s− 1) with a short time-lag (ca. 0.42 s), and thereafter they frequently turned so that they remained within the odour plume. Once moved out of the odour plume, the amphipods quickly returned to the plume with a shorter response time (ca. 0.1 s) than that in the first detection of the odour plume, suggesting that the sensory adaptation is involved with the tracking of the odour. Our study demonstrated that chemoreception is a major factor causing behavioural change in scavenging amphipods at the edge of the odour plume. 相似文献
138.
In social insects, caste-specific characters develop in the postembryonic differentiation processes. However, the mechanisms
of caste-specific organ development have yet to be elucidated. In order to obtain insights into the relationship between caste
differentiation and the regulation of organ development, we determined the caste-developmental pathway and observed compound-eye
development accompanying alate differentiation in the dry-wood termite, Neotermes koshunensis. As previously reported in other Neotermes, this species has a linear caste-developmental pathway, comprising six larval- and two nymphal-instar stages. Although the
apparent eye formation occurs during the last nymphal stages, just prior to the imaginal molt, individuals possess eye primordia
from the first larval-instar stage. The outer morphological structure of the eye was observed from the third larval-instar
stage. The detailed differentiation of cells constituting ommatidia appeared to occur in relatively young larval instars (fourth
stage), although the pigmentation of pigment cells and detailed structural formation of ommatidia occurred during the final
stage of alate development, i.e., during the late second nymphal-instar stage. This suggests that eye development is arrested
in the larval stages, and then resumed during the late nymphal stage to complete functional eye formation, which is required
for nuptial flight. In comparison to major hemimetabolous insects, which possess functional compound eyes even at the first
instar larva, this termite species shows the heterochronic shift in terms of compound-eye development.
Received 20 March 2006; revised 24 September 2006; accepted 4 October 2006. 相似文献
139.
140.
Hirashima S Oka T Ikegashira K Noji S Yamanaka H Hara Y Goto H Mizojiri R Niwa Y Noguchi T Ando I Ikeda S Hashimoto H 《Bioorganic & medicinal chemistry letters》2007,17(11):3181-3186
Following the discovery of JTK-109 (1) as a potent inhibitor of hepatitis C virus NS5B RNA-dependent RNA polymerase, [(a) Hirashima, S.; Suzuki, T.; Ishida, T.; Noji, S.; Yata, S.; Ando, I.; Komatsu, M.; Ikeda, S.; Hashimoto, H. J. Med. Chem.2006, 49, 4721. (b) Hashimoto, H.; Mizutani, K.; Yoshida, A. Int. Patent Appl. WO 01/47883, 2001.] further studies toward the improvement of the cellular potency have been performed. A greater than 40-fold improvement was achieved through replacing the biphenyl moiety with a 2-morpholinophenyl group and the benzimidazole ring with the tetracyclic scaffold to afford compound 7 with an excellent replicon potency (EC(50)=7.6 nM). 相似文献