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991.
Mitsuaki Nishioka Hiroaki Takeuchi Sergio A. Con Yoshio Uehara Isao Nishimori Toshika Okumiya Yoshitaka Kumon Tetsuro Sugiura 《Microbiology and immunology》2010,54(8):442-451
To elucidate a potential role for H. pylori BabA and SabA adhesins in the pathogenesis of gastric mucosal lesions, the MBS of BabA and SabA was examined using an in‐house ABA‐ELISA. Ninety isolates from Japanese patients with gastric cancer (n= 43) and non‐cancerous (n= 47) lesions were subjected to an ABA‐ELISA which had been developed in‐house, and sequential analysis of the babA2 middle region. The BabA‐MBS was significantly higher in the cancer than the non‐cancer group (P= 0.019), but there was no significant difference for SabA‐MBS. A weak correlation between BabA‐MBS and SabA‐MBS (r= 0.418) was observed, the positive correlation being higher in the cancer than the non‐cancer group (r= 0.598 and 0.288, respectively). The isolates were classified into two groups: a BabA‐high‐binding and a BabA‐low‐binding group (in comparison to the average for BabA‐MBS). The average SabA‐MBS in the BabA‐high‐binding group was significantly higher than in the BabA‐low‐binding group (P < 0.0001). Analysis of babA2 middle region diversity (AD1–5) revealed that AD2‐type was predominant in isolates irrespective of BabA‐MBS. H. pylori BabA‐MBS might have an effect on SabA‐MBS and relate to the severity of gastric disorders, including gastric cancer. Evaluation of MBS of the combined two adhesins would be helpful for predicting damage in the H. pylori infected stomach. 相似文献
992.
Yoshio Matsuda Hidehito Kato Ken'ichi Imanishi Minoru Mitani Hiroaki Ohta Takehiko Uchiyama 《Microbiology and immunology》2010,54(1):38-45
The aim of this study was to determine the percentage of CD45RO+ T cells in umbilical cord blood from neonates born at less than 37 weeks of gestation. Fifty-nine patients were enrolled in this study, including 49 with preterm and 10 with term deliveries. Preterm deliveries were divided into two categories; spontaneous (Group A, n = 31) and indicated (Group B, n = 18). Perinatal infection was categorized as C-CAM, H-CAM and neonatal infection. The percentage of CD45RO+ T cells in the umbilical cord was assessed using flow cytometry. IL-6 was measured using ELISA. In Group A, the percentage of CD45RO+ T cells and concentrations of IL-6 in patients with perinatal infection ( n = 18) were significantly higher than in those without perinatal infection ( n = 13). A significant correlation between percentage of CD45RO+ T cells and IL-6 concentrations was observed in the cord blood ( r = 0.62, P = 0.001). In Group B, pink–tinged amniotic fluid was observed in seven cases. In these cases, an increase in the percentage of CD45RO+ T cells (>10%) was noted. In the cases without perinatal infection, which included all those delivered at term ( n = 32), no correlation was observed between the percentage of CD45RO+ T cells and gestational age at delivery ( r =−0.139, P = 0.448). We concluded that a high percentage of CD45RO+ cord blood T cells is observed not only in perinatal infection, but also in the presence of abnormal perinatal events such as maternal bleeding in preterm gestation. 相似文献
993.
994.
Masaki Igarashi Jun-ichi Osuga Masashi Isshiki Motohiro Sekiya Hiroaki Okazaki Satoru Takase Mikio Takanashi Keisuke Ohta Masayoshi Kumagai Makiko Nishi Toshiro Fujita Ryozo Nagai Takashi Kadowaki Shun Ishibashi 《Journal of lipid research》2010,51(2):274-285
Neutral cholesterol ester hydrolase (NCEH) accounts for a large part of the nCEH activity in macrophage foam cells, a hallmark of atherosclerosis, but its subcellular localization and structure-function relationship are unknown. Here, we determined subcellular localization, glycosylation, and nCEH activity of a series of NCEH mutants expressed in macrophages. NCEH is a single-membrane-spanning type II membrane protein comprising three domains: N-terminal, catalytic, and lipid-binding domains. The N-terminal domain serves as a type II signal anchor sequence to recruit NCEH to the endoplasmic reticulum (ER) with its catalytic domain within the lumen. All of the putative N-linked glycosylation sites (Asn270, Asn367, and Asn389) of NCEH are glycosylated. Glycosylation at Asn270, which is located closest to the catalytic serine motif, is important for the enzymatic activity. Cholesterol loading by incubation with acetyl-LDL does not change the ER localization of NCEH. In conclusion, NCEH is targeted to the ER of macrophages, where it hydrolyzes CE to deliver cholesterol for efflux out of the cells. 相似文献
995.
Satoshi Mikami Tominari Kobayashi Kodai Machida Mamiko Masutani Shigeyuki Yokoyama Hiroaki Imataka 《Biotechnology letters》2010,32(7):897-902
Human cell-derived in vitro protein synthesis systems are useful for the production of recombinant proteins. Productivity can be increased by supplementation with GADD34, a protein that is difficult to express in and purify from E. coli. Deletion of the N-terminal 120 or 240 amino acids of GADD34 improves recovery of this protein from E. coli without compromising its ability to boost protein synthesis in an in vitro protein synthesis system. The use of N-terminally truncated GADD34 proteins in place of full-length GADD34 should improve the utility of human cell-based cell-free protein synthesis systems. 相似文献
996.
Yoichi Toyokawa Hiroaki Takahara Alissara Reungsang Masakazu Fukuta Yuki Hachimine Shinjiro Tachibana Masaaki Yasuda 《Applied microbiology and biotechnology》2010,86(6):1867-1875
A gram-positive thermotolerant bacterium, designated strain RKK-04, was isolated from a fermented Thai fish sauce broth as
it demonstrated high proteolytic activity. A phylogenetic analysis based on comparisons of 16S rRNA gene sequences showed
that strain RKK-04 is Bacillus licheniformis. The proteolytic enzyme, which was purified 80-fold with 18% yield, has a molecular mass of 31 kDa and an isoelectric point
higher than 9.3. The optimum pH and temperature of the enzyme activity were found to be 10.0 and 50°C, respectively. The addition
of diisopropyl fluorophosphate and phenylmethanesulfonyl fluoride completely inhibited enzymatic activity. These results showed
that the enzyme is a subtilisin-like alkaline serine proteinase. On the other hand, the enzyme exhibited unique cleavage sites
in oxidized insulin B-chain that differed from those of other subtilisin-like proteases. High enzymatic activity was also
retained under high salt conditions (30% NaCl). The myosin heavy chain of fish protein was completely digested by reaction
with this enzyme. Thus the halotolerant proteinase from B. licheniformis RKK-04 is a key enzyme for fish sauce fermentation. 相似文献
997.
Sun Mee Hong Jun Yamashita Hitoshi Mitsunobu Keiro Uchino Isao Kobayashi Hideki Sezutsu Toshiki Tamura Hideki Nakajima Yoshitaka Miyagawa Jae Man Lee Hiroaki Mon Yoshihiko Miyata Yutaka Kawaguchi Takahiro Kusakabe 《Applied microbiology and biotechnology》2010,87(6):2147-2156
Baculovirus expression systems (BES) are widely used for recombinant protein production in lepidopteran cells or larvae. However, even in BES, the insolubility of recombinant proteins sometimes makes their expression difficult. In this study, to improve the solubility and yield of foreign proteins, we constructed transgenic silkworms using silkworm heat-shock proteins, Hsp70 and Hsp40, or Hsc70 and Hsp90 co-chaperone Hop. In these transgenic silkworms, the expression levels of the transgenes were under the control of a UAS·hsp mini-promoter driven by a Gal4NFkBp65 activator. When the transgenic silkworm with HSP70 and 40 (TGS-HSP70/40) was infected with BmNPV carrying mC3d and Gal4NFkBp65 under the control of baculovirus polyhedrin or p10 promoters, respectively, the soluble fraction of the His- or His·GST-tagged mC3d increased significantly. Similarly, the transgenic silkworm with HSC70 and HOP (TGS-HOP7) was effective for the expression of a steroid hormone receptor, USP2. In conclusion, the His-tagged baculovirus expression system featuring the chaperone effect TGS-HSP70/40 and TGS-HOP7 silkworms is effective for increasing the yields of soluble and functional foreign gene products. 相似文献
998.
Sato Y Shibata H Nakatsu T Nakano H Kashiwayama Y Imanaka T Kato H 《The EMBO journal》2010,29(24):4083-4093
Peroxisomes require peroxin (Pex) proteins for their biogenesis. The interaction between Pex3p, which resides on the peroxisomal membrane, and Pex19p, which resides in the cytosol, is crucial for peroxisome formation and the post-translational targeting of peroxisomal membrane proteins (PMPs). It is not known how Pex3p promotes the specific interaction with Pex19p for the purpose of PMP translocation. Here, we present the three-dimensional structure of the complex between a cytosolic domain of Pex3p and the binding-region peptide of Pex19p. The overall shape of Pex3p is a prolate spheroid with a novel fold, the 'twisted six-helix bundle.' The Pex19p-binding site is at an apex of the Pex3p spheroid. A 16-residue region of the Pex19p peptide forms an α-helix and makes a contact with Pex3p; this helix is disordered in the unbound state. The Pex19p peptide contains a characteristic motif, consisting of the leucine triad (Leu18, Leu21, Leu22), and Phe29, which are critical for the Pex3p binding and peroxisome biogenesis. 相似文献
999.
Yuji Shono Masahiro Kamouchi Takanari Kitazono Junya Kuroda Kuniyuki Nakamura Noriko Hagiwara Hiroaki Ooboshi Setsuro Ibayashi Mitsuo Iida 《Cellular and molecular neurobiology》2010,30(3):453-460
Brain hypoxia or ischemia causes acidosis and the intracellular accumulation of Ca2+ in neuron. The aims of the present study were to elucidate the interaction between intracellular pH and Ca2+ during transient acidosis and its effects on the viability of neuronal and glial cells. Intracellular Ca2+ and pH were measured using the fluorescence of fura-2 and 2′,7′-bis(2-carboxyethyl)-5(6)-carboxyfluorescein acetoxymethyl
ester in neuroblastoma (IMR-32), glioblastoma (T98G), and astrocytoma (CCF-STTG1) cell lines. The administration of 5 mM propionate
caused intracellular acidification in IMR-32 and T98G cells but not in CCF-STTG1 cells. After the removal of propionate, the
intracellular pH recovered to the resting level. The intracellular Ca2+ transiently increased upon the removal of propionate in IMR-32 and T98G cells but not in CCF-STTG1 cells. The transient Ca2+ increase caused by the withdrawal of intracellular acidification was abolished by the removal of external Ca2+, diminished by a reduction of external Na+, and inhibited by benzamil. Transient acidosis caused cell death, whereas the cells were more viable in the absence of external
Ca2+. Benzamil alleviated cell death caused by transient acidosis in IMR-32 and T98G cells but not in CCF-STTG1 cells. These results
suggest that recovery from intracellular acidosis causes a transient increase in cytosolic Ca2+ due to reversal of Ca2+ transport via Na+/Ca2+ exchanger coactivated with Na+/H+ exchanger, which can cause cell death. 相似文献
1000.