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1.
Takahiro Watanabe Yohei Narita Masahiro Yoshida Yoshitaka Sato Fumi Goshima Hiroshi Kimura Takayuki Murata 《Journal of virology》2015,89(19):10120-10124
Epstein-Barr virus (EBV) is a gammaherpesvirus, associated with infectious mononucleosis and various types of malignancy. We focused here on the BDLF4 gene of EBV and identified it as a lytic gene, expressed with early kinetics. Viral late gene expression of the BDLF4 knockout strain was severely restricted; this could be restored by an exogenous supply of BDLF4. These results indicate that BDLF4 is important for the EBV lytic replication cycle, especially in late gene expression. 相似文献
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3.
Antonis Kourtidis Masahiro Yanagisawa Deborah Huveldt John A. Copland Panos Z. Anastasiadis 《PloS one》2015,10(6)
Altered protein expression and phosphorylation are common events during malignant transformation. These perturbations have been widely explored in the context of E-cadherin cell-cell adhesion complexes, which are central in the maintenance of the normal epithelial phenotype. A major component of these complexes is p120 catenin (p120), which binds and stabilizes E-cadherin to promote its adhesive and tumor suppressing function. However, p120 is also an essential mediator of pro-tumorigenic signals driven by oncogenes, such as Src, and can be phosphorylated at multiple sites. Although alterations in p120 expression have been extensively studied by immunohistochemistry (IHC) in the context of tumor progression, little is known about the status and role of p120 phosphorylation in cancer. Here we show that tyrosine and threonine phosphorylation of p120 in two sites, Y228 and T916, is elevated in renal and breast tumor tissue samples. We also show that tyrosine phosphorylation of p120 at its N-terminus, including at the Y228 site is required for its pro-tumorigenic potential. In contrast, phosphorylation of p120 at T916 does not affect this p120 function. However, phosphorylation of p120 at T916 interferes with epitope recognition of the most commonly used p120 antibody, namely pp120. As a result, this antibody selectively underrepresents p120 levels in tumor tissues, where p120 is phosphorylated. Overall, our data support a role of p120 phosphorylation as a marker and mediator of tumor transformation. Importantly, they also argue that the level and localization of p120 in human cancer tissues immunostained with pp120 needs to be re-evaluated. 相似文献
4.
Distribution of Ankyrin Isoforms and Their Proteolysis After Ischemia and Reperfusion in Rat Brain 总被引:1,自引:0,他引:1
Kazuki Harada Shiro Fukuda †Manabu Kunimoto Ken-ichi Yoshida 《Journal of neurochemistry》1997,69(1):371-376
Abstract: The distribution of brain-type ankyrin (ankyrinB , 212 kDa) and erythrocyte-type ankyrin (ankyrinR , 239 kDa) was investigated in the subcellular fractions of rat forebrain (P1, 1,000 g pellet; P2, 15,000 g pellet; P3, 100,000 g pellet; S, 100,000 g supernatant) by immunoblotting using specific antibodies. The P2 fraction contained ∼40% of the 212- and 163-kDa isoforms of ankyrinB and the 239-kDa isoform of ankyrinR . Further subfractionation of the P2 by Percoll gradient centrifugation followed by separation of myelin showed association of the three ankyrin isoforms with the synaptosome-rich fraction but not with the myelin-rich fraction. The plasma membrane-rich P3 fraction contained a concentration of ankyrin isoforms similar to that in the P2 fraction. In vitro proteolysis of ankyrin in the P2 fraction with calpain showed that the 212-kDa ankyrinB was more susceptible to calpain than was ankyrinR . In the two-vessel occlusion model, ischemia for 30 min generated the 160-kDa fragment of ankyrinR , and reperfusion for 60 min after 30 min of ischemia remarkably increased the 160-kDa fragment. The reperfusion also significantly decreased the 212-kDa isoform of ankyrinB . Both ischemia-reperfusion and in vitro proteolysis with calpain generated the 160-kDa fragment of ankyrinR , suggesting the involvement of calpain. 相似文献
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A case of chromomycosis in which hyperthermia proved effective is reported. The patient was a 56-year-old male bean curd maker who, without any previous history of minor trauma, developed on the extensor side of the left upper arm an eczematous lesion that underwent gradual radial expansion. The lesion showed a well-defined, 7×10 cm infiltrated erythematous plaque with the central area healed and, at the upper and lower borders, adherent scales and crusts on the surface. Histological examination revealed granulomatous changes in the dermis, as well as sclerotic cells within giant cells and microabscesses. On culturing,Fonsecaea pedrosoi was isolated. The patient was treated with disposable chemical pocket warmers, which were secured over the lesion with a rather tight elastic bandage, so that they kept the affected area warm for 24 hours a day. After a month of such hyperthermic treatment, the erythema and infiltration had decreased considerably, and microscopic examination and culture of the crusts both yielded negative results. Examination of biopsy specimens of the lesion after the third month showed that it had cicatrized. The treatment was stopped after 4 months, and no relapse occurred. We also summarize the published results of local hyperthermic treatment of chromomycosis in Japan. 相似文献
7.
Norio Ohashi Masahiro Fukuhara Masahiko Shimada Akira Tamura 《FEMS microbiology letters》1995,125(2-3):299-304
Abstract The 16S rRNA gene sequences of Rickettsia tsutsugamushi and Rickettsia sibirica were determined by PCR and DNA sequencing. Phylogenetic analysis revealed that R. sibirica is positioned in a cluster of the genus Rickettsia with a similarity value of 98.1–99.6%, whereas R. tsutsugamushi is located apart from the cluster with a similarity value of 90.2–90.6%. This evidence suggests that R. tsutsugamushi should be excluded taxonomically from the genus Rickettsia . The phylogenetic classification of six antigenic variants in R. tsutsugamushi moderately reflected their antigenic relationship known in closely and distantly related strains. 相似文献
8.
The activity of angiotensin converting enzyme (ACE) in cell lysate of cultured human umbilical vein endothelial cells (HUVEC) after a 24-hour incubation with 10(-3) and 10(-4)M of paraquat (PQ) was decreased. However, LDH released into the culture medium of HUVEC during the 24-hour incubation with PQ was not increased. Many investigators show that the change in serum ACE activity reflects the impairment of vascular endothelial cells. We showed in this report that ACE was decreased even at an early stage of endothelial injury induced by PQ, when LDH release is not yet increased. 相似文献
9.
Yoshifumi Abe Atsuhiko Matsunaga Ryota Matsuzawa Toshiki Kutsuna Shuhei Yamamoto Kei Yoneki Manae Harada Ryoma Ishikawa Takaaki Watanabe Atsushi Yoshida 《PloS one》2016,11(3)
Walking ability is significantly lower in hemodialysis patients compared to healthy people. Decreased walking ability characterized by slow walking speed is associated with adverse clinical events, but determinants of decreased walking speed in hemodialysis patients are unknown. The purpose of this study was to identify factors associated with slow walking speed in ambulatory hemodialysis patients. Subjects were 122 outpatients (64 men, 58 women; mean age, 68 years) undergoing hemodialysis. Clinical characteristics including comorbidities, motor function (strength, flexibility, and balance), and maximum walking speed (MWS) were measured and compared across sex-specific tertiles of MWS. Univariate and multivariate logistic regression analyses were performed to examine whether clinical characteristics and motor function could discriminate between the lowest, middle, and highest tertiles of MWS. Significant and common factors that discriminated the lowest and highest tertiles of MWS from other categories were presence of cardiac disease (lowest: odds ratio [OR] = 3.33, 95% confidence interval [CI] = 1.26–8.83, P<0.05; highest: OR = 2.84, 95% CI = 1.18–6.84, P<0.05), leg strength (OR = 0.62, 95% CI = 0.40–0.95, P<0.05; OR = 0.57, 95% CI = 0.39–0.82, P<0.01), and standing balance (OR = 0.76, 95% CI = 0.63–0.92, P<0.01; OR = 0.81, 95% CI = 0.68–0.97, P<0.05). History of fracture (OR = 3.35, 95% CI = 1.08–10.38; P<0.05) was a significant factor only in the lowest tertile. Cardiac disease, history of fracture, decreased leg strength, and poor standing balance were independently associated with slow walking speed in ambulatory hemodialysis patients. These findings provide useful data for planning effective therapeutic regimens to prevent decreases in walking ability in ambulatory hemodialysis patients. 相似文献
10.
Sau3AI-generated DNA fragments of the Shigella sonnei large plasmid encoding the form I antigen were cloned into Escherichia coli with cosmid vector pHSG262. One resulting plasmid, designated pJK1137, was studied further. Restriction endonuclease mapping and analysis of transposon Tn3 insertion mutants demonstrated that the form I antigen genes were located within a region of about 12.6 kb consisting of the two contiguous HindIII fragments of 1.26 kb and 12.4 kb. The results of complementation studies between Tn3 insertion mutants of pJK1137 and recombinant plasmids carrying different parts of the form I antigen genes indicated that the 12.6 kb DNA sequence contained at least four gene clusters, regions A, B, C and D. Analysis of radioactively labelled proteins in minicells demonstrated that the DNA sequence of about 12.6 kb coded for at least four specific proteins of 42, 23, 48 and 39 kDa. The former two were coded by region A, the latter two by region D. 相似文献