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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.
A bio-inspired photoresponse was engineered in porphyrin-attached Au nanoparticles (AuNPs) on a field-effect transistor (FET). The system mimics photosynthetic electron transfer, using porphyrin derivatives as photosensitizers and AuNPs as photoelectron counting devices. Porphyrin-protected AuNPs were immobilized onto the gate of an FET via the formation of self-assembled monolayers. Photoinduced electron transfer from the porphyrin led to single electron transfer at the Au nanoparticles, which was monitored via a changing gate voltage on the FET in the presence of organic electrolyte. The further attachment of other functional molecules to this system should enable various other potential functionalities. This article is part of a Special Issue entitled: Photosynthesis Research for Sustainability: Keys to Produce Clean Energy. 相似文献
103.
Naoki Yamamoto Koji Hirano Hajime Kojima Mariko Sumitomo Hiromi Yamashita Masahiko Ayaki Koki Taniguchi Atsuhiro Tanikawa Masayuki Horiguchi 《In vitro cellular & developmental biology. Animal》2010,46(9):774-780
Stem/progenitor cells of the human corneal epithelium are present in the human corneal limbus, and several corneal epithelial
stem/progenitor cell markers have been reported. Recently, the neurotrophin family receptors were reported to be useful markers
of corneal epithelial stem/progenitor cells. Therefore, we examined an enzymatic separation method for obtaining corneal epithelial
stem/progenitor cells and measuring the change in the expression of low-affinity neurotrophin receptor p75 (p75NTR), a receptor belonging to the neurotrophin family. As a result, it was found that our separation method preserved cell viability.
Furthermore, p75NTR was mainly observed in epithelial basal cells as were the corneal epithelial stem/progenitor markers p63 and integrin β1.
p75NTR was also observed in the cultured cells, but its frequency decreased with passage. In conclusion, we propose that our culture
method will enable the culture of corneal stem cells and that it is a useful tool for elucidating the molecular basis of the
niche that is necessary for the maintenance of epithelial stem cells in the corneal limbus. Furthermore, we conclude that
p75NTR is a useful cell marker for evaluating the characteristics of stem/progenitor cells in culture. 相似文献
104.
Naotaka Sekiyama Kyohei Arita Yoshihiro Ikeda Kohtaro Hashiguchi Mariko Ariyoshi Hidehito Tochio Hisato Saitoh Masahiro Shirakawa 《Proteins》2010,78(6):1491-1502
Post‐translational modification by small ubiquitin‐like modifier (SUMO) provides an important regulatory mechanism in diverse cellular processes. Modification of SUMO has been shown to target proteins involved in systems ranging from DNA repair pathways to the ubiquitin‐proteasome degradation system by the action of SUMO‐targeted ubiquitin ligases (STUbLs). STUbLs recognize target proteins modified with a poly‐SUMO chain through their SUMO‐interacting motifs (SIMs). STUbLs are also associated with RENi family proteins, which commonly have two SUMO‐like domains (SLD1 and SLD2) at their C terminus. We have determined the crystal structures of SLD2 of mouse RENi protein, Nip45, in a free form and in complex with a mouse E2 sumoylation enzyme, Ubc9. While Nip45 SLD2 shares a β‐grasp fold with SUMO, the SIM interaction surface conserved in SUMO paralogues does not exist in SLD2. Biochemical data indicates that neither tandem SLDs or SLD2 of Nip45 bind to either tandem SIMs from either mouse STUbL, RNF4 or to those from SUMO‐binding proteins, whose interactions with SUMO have been well characterized. On the other hand, Nip45 SLD2 binds to Ubc9 in an almost identical manner to that of SUMO and thereby inhibits elongation of poly‐SUMO chains. This finding highlights a possible role of the RENi proteins in the modulation of Ubc9‐mediated poly‐SUMO formation. Proteins 2010. © 2009 Wiley‐Liss, Inc. 相似文献
105.
Mariko Kato Nahoko Nagasaki-Takeuchi Yuki Ide Rie Tomioka Masayoshi Maeshima 《Plant signaling & behavior》2010,5(7):848-850
In plants, Ca2+, phosphatidylinositol phosphates (PtdInsPs) and inositol phosphates are major components of intracellular signaling. Several kinds of proteins and enzymes, such as calmodulin (CaM), protein kinase, protein phosphatase, and the Ca2+ channel, mediate the signaling. Two new Ca2+-binding proteins were identified from Arabidopsis thaliana and named PCaP1 and PCaP2 [plasma membrane (PM)-associated Ca2+(cation)-binding protein 1 and 2]. PCaP1 has an intrinsically disordered region in the central and C-terminal parts. The PCaP1 gene is expressed in most tissues and the PCaP2 gene is expressed predominantly in root hairs and pollen tubes. We recently demonstrated that these proteins are N-myristoylated, stably anchored in the PM, and are bound with phosphatidylinositol phosphates, especially PtdInsP2s. Here we propose a model for the switching mechanism of Ca2+-signaling mediated by PtdInsPs. Ca2+ forms a complex with CaM (Ca2+-CaM) when there is an increase in the cytosol free Ca2+. The binding of PCaPs with Ca2+-CaM causes PCaPs to release PtdInsPs. Until the release of PtdInsPs, the signaling is kept in the resting state.Key words: calcium signal, calmodulin, inositol phosphate, intrinsically disordered protein, myristoylation, phosphatidylinositol phosphate, plasma membrane 相似文献
106.
Tomoo Shirabe Mariko Omura Yuko Osaki Etsuro Yoshimura 《Biological trace element research》2010,138(1-3):13-21
Growth of Cyanidioschyzon merolae was inhibited depending on the cadmium(II) concentration in the culture medium. Although a lower level (0.01 mM) of Cd(II) inhibited growth by a factor of 0.5, higher levels (0.1 and 1 mM) induced lag periods of 10–14 days. Algal cells pretreated with 1 mM Cd(II) for 27 days grew steadily in 1 mM Cd(II) without the lag period, demonstrating that the cells became Cd(II) resistant (CdR). Cells remained resistant after four cycles (7 days per cycle) of washing and re-growing in medium without Cd(II), while intracellular Cd(II) decreased to undetectable levels. These results suggest that the Cd(II)-resistant phenotype is heritable. This phenomena may be attributable to the presence of genetic inhomogeneity in the wild-type cell populations or to mutagenesis caused by Cd(II) stress. Intracellular Cd(II) levels significantly decreased in the CdR phenotype compared to the wild-type cells, indicating that resistant cells may have a defective gene that codes for Cd(II)-uptake protein or the ability to secrete Cd(II). 相似文献
107.
Mariko Ishibashi Takaji Wakita 《Biochemical and biophysical research communications》2010,392(3):397-402
We found the 2′,5′-oligoadenylate synthetase-like (OASL) gene to be significantly elevated by high virus loads in human liver infected with hepatitis C virus (HCV). Here, we determined whether OASL inhibited HCV replication using an in vitro system. We constructed three expression vectors of OASL to produce isoform a (OASLa), isoform b (OASLb), and the C-terminal ubiquitin-like domain of isoform a (Ub). When Huh7 JFH-1 HCV replicon cells were separately transfected with these three vectors, colony formation of HCV-replicating cells was inhibited by 95%, 94%, and 65%, respectively. Both OASLa and OASLb were also inhibitory for cells as well as the virus because colony formation of OASL-producing cells was reduced to 41% and 8%, respectively. Stable Huh7 clones producing each of the three OASLs were established and assessed for their inhibition of HCV replication using luciferase reporter gene-containing JFH-1 replicon RNA. HCV replication was inhibited by 50-90% in several stable OASL clones. Association analysis in six Ub clones expressing different levels of Ub mRNA showed that the degree of inhibition of HCV replication was significantly associated with the amount of Ub present. In conclusion, OASL possesses two domains with HCV inhibitory activity. The N-terminal OAS-homology domain without OAS activity is inhibitory for cell growth as well as HCV replication, whereas C-terminal Ub is inhibitory only for HCV replication. Therefore, OASLa, a major isoform of this molecule induced in human liver, may mediate anti-HCV activity through two different domains. 相似文献
108.
Karin Hayashi Mariko Makino Masahiro Hashizume Koichi Nakano Koji Tsuboi 《BioPsychoSocial medicine》2010,4(1):9
Background
Since the 1980s, a high EEG abnormality rate has been reported for patients with panic disorder. However, how the EEG abnormalities of panic disorder patients are related to the clinical features and pathology of these patients has yet to be clarified. In this study we investigated whether or not EEG abnormalities are related to the 13 symptoms in the DSM-IV criteria for a diagnosis of panic attacks. 相似文献109.
Broad specificity amino acid racemase (E.C. 5.1.1.10) from Pseudomonas putida IFO 12996 (BAR) is a unique racemase because of its broad substrate specificity. BAR has been considered as a possible catalyst
which directly converts inexpensive l-amino acids to dl-amino acid racemates. The gene encoding BAR was cloned to utilize BAR for the synthesis of d-amino acids, especially d-Trp which is an important intermediate of pharmaceuticals. The substrate specificity of cloned BAR covered all of the standard
amino acids; however, the activity toward Trp was low. Then, we performed random mutagenesis on bar to obtain mutant BAR derivatives with high activity for Trp. Five positive mutants were isolated after the two-step screening
of the randomly mutated BAR. After the determination of the amino acid substitutions in these mutants, it was suggested that
the substitutions at Y396 and I384 increased the Trp specific racemization activity and the racemization activity for overall
amino acids, respectively. Among the positive mutants, I384M mutant BAR showed the highest activity for Trp. l-Trp (20 mM) was successfully racemized, and the proportion of d-Trp was reached 43% using I384M mutant BAR, while wild-type BAR racemized only 6% of initial l-Trp. 相似文献
110.
Hirata S Matsuyoshi H Fukuma D Kurisaki A Uemura Y Nishimura Y Senju S 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(2):918-925
We previously reported the protection from myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE) by the adoptive transfer of genetically modified embryonic stem cell-derived dendritic cells (ES-DC) presenting MOG peptide in the context of MHC class II molecules and simultaneously expressing TRAIL (ES-DC-TRAIL/MOG). In the present study, we found the severity of EAE induced by another myelin autoantigen, myelin basic protein, was also decreased after treatment with ES-DC-TRAIL/MOG. This preventive effect diminished, if the function of CD4(+)CD25(+) regulatory T cells (Treg) was abrogated by the injection of anti-CD25 mAb into mice before treatment with ES-DC-TRAIL/MOG. The adoptive transfer of CD4(+)CD25(+) T cells from ES-DC-TRAIL/MOG-treated mice protected the recipient mice from MOG- or myelin basic protein-induced EAE. The number of Foxp3(+) cells increased in the spinal cords of mice treated with ES-DC-TRAIL/MOG. In vitro experiments showed that TRAIL expressed in genetically modified ES-DC and also in LPS-stimulated splenic macrophages had a capacity to augment the proliferation of CD4(+)CD25(+) T cells. These results suggest that the prevention of EAE by treatment with ES-DC-TRAIL/MOG is mediated, at least in part, by MOG-reactive CD4(+)CD25(+) Treg propagated by ES-DC-TRAIL/MOG. For the treatment of organ-specific autoimmune diseases, induction of Treg reactive to the organ-specific autoantigens by the transfer of DC-presenting Ags and simultaneously overexpressing TRAIL therefore appears to be a promising strategy. 相似文献