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101.
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102.
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
103.
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
104.
The possibility that a loss of pollen viability during dry storage in a freezer is caused by the reduced pollen capacity to enhance polyamine biosynthetic enzyme activity after rehydration was investigated using pollen grains of tomato (Solanum lycopersicum=Lycopersicon esculentum) stored at -30 degrees C under dry conditions for up to 42 months. Pollen grains showed normal germinability for at least 12 months in storage, but those stored for longer than 24 months exhibited a significant reduction in germinability and fruit-setting ability. This age-dependent reduction in pollen viability coincided with the extent to which the pollen lost the capacity to increase arginine decarboxylase (ADC) and S-adenosylmethionine decarboxylase (SAMDC) activities and polyamine contents upon rehydration. Immunoblot analysis indicated that the capacity of pollen to translate ADC and SAMDC mRNAs was impaired in accordance with the loss of viability. Also, the capacity to synthesize proteins in general decreased with the increase in storage duration. The addition of 1 mM putrescine, spermidine, or spermine to incubation medium promoted germination, impregnation of pollen grains with 1 mM spermidine restored fertilization ability, and the addition of 1 mM spermidine to incubation medium promoted protein synthesis exclusively in pollen grains which had been stored for a long time. These results indicate that the reduction in viability of tomato pollen during long-term dry storage in a freezer involves a decline in the capacity to enhance gene translation for polyamine biosynthetic enzymes upon rehydration. 相似文献
105.
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
106.
107.
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
108.
Kudo T Fujii T Ikegami S Inokuchi K Takayama Y Ikehara Y Nishihara S Togayachi A Takahashi S Tachibana K Yuasa S Narimatsu H 《Glycobiology》2007,17(1):1-9
The 3-fucosyl-N-acetyllactosamine [Lewis x (Le(x)), CD15, SSEA-1] carbohydrate structure is expressed on several glycolipids, glycoproteins, and proteoglycans of the nervous system and has been implicated in cell-cell recognition, neurite outgrowth, and neuronal migration during development. To characterize the functional role of Le(x) carbohydrate structure in vivo, we have generated mutant mice that lack alpha1,3-fucosyltransferase IX (Fut9(-/-)). Fut9(-/-) mice were unable to synthesize the Le(x) structure carried on glycoproteins and glycolipids in embryonic and adult brain. However, no obvious pathological differences between wild-type and Fut9(-/-) mice were found in brain. In behavioral tests, Fut9(-/-) mice exhibited increased anxiety-like responses in dark-light preference and in elevated plus maze tests. Immunohistochemical analysis showed that the number of calbindin-positive neurons was decreased in the basolateral amygdala in Fut9(-/-) mice. These observations indicated that the carbohydrates synthesized by Fut9 play critical roles in functional regulations of interneurons in the amygdalar subdivisions and suggested a role for the Le(x) structure in some aspects of emotional behavior in mice. 相似文献
109.
Removal and recovery of phosphorous from swine wastewater by demonstration crystallization reactor and struvite accumulation device 总被引:10,自引:0,他引:10
Suzuki K Tanaka Y Kuroda K Hanajima D Fukumoto Y Yasuda T Waki M 《Bioresource technology》2007,98(8):1573-1578
A demonstration crystallization reactor and struvite accumulation device for the removal and recovery of phosphorous was constructed and their performance was evaluated using actual swine wastewater for 3.5 years. The wastewater pH was increased by aeration, and the concentrations of total P and soluble PO(4)-P were reduced by a struvite crystallization reaction induced under a high pH condition. A 30% MgCl(2) addition was effective in enhancing the struvite crystallization reaction. The concentrations of suspended solids, total Zn and total Cu, were also decreased by the settling function of the reactor. On removing the efficiencies of these components, no noticeable seasonal fluctuation in performance was observed during the 3.5-year operation. In terms of maximum yield, 171g struvite was obtained from 1m(3) swine wastewater by the demonstration accumulation device for struvite recovery. The recovered struvite needed only air-drying before use since it was approximately 95% pure even without washing. 相似文献
110.