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961.
Choi MK Moon CH Ko MS Lee UH Cho WJ Cha SJ Do JW Heo GJ Jeong SG Hahm YS Harmache A Bremont M Kurath G Park JW 《PloS one》2011,6(7):e22362
The nonvirion (NV) protein of infectious hematopoietic necrosis virus (IHNV) has been previously reported to be essential for efficient growth and pathogenicity of IHNV. However, little is known about the mechanism by which the NV supports the viral growth. In this study, cellular localization of NV and its role in IHNV growth in host cells was investigated. Through transient transfection in RTG-2 cells of NV fused to green fluorescent protein (GFP), a nuclear localization of NV was demonstrated. Deletion analyses showed that the (32)EGDL(35) residues were essential for nuclear localization of NV protein, and fusion of these 4 amino acids to GFP directed its transport to the nucleus. We generated a recombinant IHNV, rIHNV-NV-ΔEGDL in which the (32)EGDL(35) was deleted from the NV. rIHNVs with wild-type NV (rIHNV-NV) or with the NV gene replaced with GFP (rIHNV-ΔNV-GFP) were used as controls. RTG-2 cells infected with rIHNV-ΔNV-GFP and rIHNV-NV-ΔEGDL yielded 12- and 5-fold less infectious virion, respectively, than wild type rIHNV-infected cells at 48 h post-infection (p.i.). While treatment with poly I∶C at 24 h p.i. did not inhibit replication of wild-type rIHNVs, replication rates of rIHNV-ΔNV-GFP and rIHNV-NV-ΔEGDL were inhibited by poly I∶C. In addition, both rIHNV-ΔNV and rIHNV-NV-ΔEGDL induced higher levels of expressions of both IFN1 and Mx1 than wild-type rIHNV. These data suggest that the IHNV NV may support the growth of IHNV through inhibition of the INF system and the amino acid residues of (32)EGDL(35) responsible for nuclear localization are important for the inhibitory activity of NV. 相似文献
962.
Infection with Edwardsiella tarda, a gram-negative bacterium, causes high morbidity and mortality in both marine and freshwater fish. Outer membrane vesicles (OMVs) released from gram-negative bacteria are known to play important roles in bacterial pathogenesis and host immune responses, but no such roles for E. tarda OMVs have yet been described. In the present study, we investigated the proteomic composition of OMVs and the immunostimulatory effect of OMVs in a natural host, as well as the efficacy of OMVs when used as a vaccine against E. tarda infection. A total of 74 proteins, from diverse subcellular fractions, were identified in OMVs. These included a variety of important virulence factors, such as hemolysin, OmpA, porin, GAPDH, EseB, EseC, EseD, EvpC, EvpP, lipoprotein, flagellin, and fimbrial protein. When OMVs were administrated to olive flounder, significant induction of mRNAs encoding IL-1β, IL-6, TNFα, and IFNγ was observed, compared with the levels seen in fish injected with formalin-killed E. tarda. In a vaccine trial, olive flounder given OMVs were more effectively protected (p<0.0001) than were control fish. Investigation of OMVs may be useful not only for understanding the pathogenesis of E. tarda but also in development of an effective vaccine against edwardsiellosis. 相似文献
963.
Overexpression of jasmonic acid carboxyl methyltransferase increases tuber yield and size in transgenic potato 总被引:3,自引:0,他引:3
Hwang Bae Sohn Han Yong Lee Ju Seok Seo Choonkyun Jung Jae Heung Jeon Jeong-Han Kim Yin Won Lee Jong Seob Lee Jong-Joo Cheong Yang Do Choi 《Plant biotechnology reports》2011,5(1):27-34
Jasmonates control diverse plant developmental processes, such as seed germination, flower, fruit and seed development, senescence
and tuberization in potato. To understand the role of methyl jasmonate (MeJA) in potato tuberization, the Arabidopsis
JMT gene encoding jasmonic acid carboxyl methyltransferase was constitutively overexpressed in transgenic potato plants. Increases
in tuber yield and size as well as in vitro tuberization frequency were observed in transgenic plants. These were correlated
with JMT mRNA level––the higher expression level, the higher the tuber yield and size. The levels of jasmonic acid (JA), MeJA and
tuberonic acid (TA) were also higher than those in control plants. Transgenic plants also exhibited higher expression of jasmonate-responsive
genes such as those for allene oxide cyclase (AOC) and proteinase inhibitor II (PINII). These results indicate that JMT overexpression induces jasmonate biosynthesis genes and thus JA and TA pools in transgenic potatoes. This results in enhanced
tuber yield and size in transgenic potato plants. 相似文献
964.
Background
Current chemotherapeutic drugs kill cancer cells mainly by inducing apoptosis. However, they become ineffective once cancer cell has the ability to metastasize, hence the poor prognosis and high mortality rate. Therefore, the purpose of this study was to evaluate the antimetastatic potential of Phyllanthus (P. niruri, P. urinaria, P. watsonii, and P. amarus) on lung and breast carcinoma cells.Methodology/Principal Findings
Cytotoxicity of Phyllanthus plant extracts were first screened using the MTS reduction assay. They were shown to inhibit MCF-7 (breast carcinoma) and A549 (lung carcinoma) cells growth with IC50 values ranging from 50–180 µg/ml and 65–470 µg/ml for methanolic and aqueous extracts respectively. In comparison, they have lower toxicity on normal cells with the cell viability percentage remaining above 50% when treated up to 1000 µg/ml for both extracts. After determining the non-toxic effective dose, several antimetastasis assays were carried out and Phyllanthus extracts were shown to effectively reduce invasion, migration, and adhesion of both MCF-7 and A549 cells in a dose-dependent manner, at concentrations ranging from 20–200 µg/ml for methanolic extracts and 50–500 µg/ml for aqueous extracts. This was followed by an evaluation of the possible modes of cell death that occurred along with the antimetastatic activity. Phyllanthus was shown to be capable of inducing apoptosis in conjunction with its antimetastastic action, with more than three fold increase of caspases-3 and -7, the presence of DNA-fragmentation and TUNEL-positive cells. The ability of Phyllanthus to exert antimetastatic activities is mostly associated to the presence of polyphenol compounds in its extracts.Conclusions/Significance
The presence of polyphenol compounds in the Phyllanthus plant is critically important in the inhibition of the invasion, migration, and adhesion of cancer cells, along with the involvement of apoptosis induction. Hence, Phyllanthus could be a valuable candidate in the treatment of metastatic cancers. 相似文献965.
Kim TH Jiang HH Lee S Youn YS Park CW Byun Y Chen X Lee KC 《Bioconjugate chemistry》2011,22(4):625-632
Dimerization is viewed as the most effective means of increasing receptor binding affinity, and both dimerization and PEGylation effectively prolong the life spans of short-lived peptides and proteins in vivo by delaying excretion via the renal route. Here, we describe the high binding affinities of two long-acting exendin-4 (Ex4) conjugates, dimerized Ex4 (Di-Ex4) and PEGylated Di-Ex-4 (PEG-Di-Ex4). Di-Ex4 and PEG-Di-Ex4 were prepared using cysteine and amine residue specific coupling reactions using Ex4-Cys, bisMal-NH(2), and activated PEG. The Ex4 conjugates produced were of high purity (>98.5%), as determined by size-exclusion chromatography and MALDI-TOF mass spectrometry. The receptor binding affinity of Di-Ex4 on RIN-m5F cells was 3.5-fold higher than that of Ex4, and the in vivo antihyperglycemic efficacy of Di-Ex4 was also greater than that of native Ex4 in type 2 diabetic db/db mice. Furthermore, Di-Ex4 and PEG-Di-Ex4 were found to have greater blood circulating t(1/2) and AUC(inf) values than native Ex4 by 2.7- and 13.7-fold, and by 4.0- and 17.3-fold, respectively. Accordingly, hypoglycemic durations were greatly increased to 15.0 and 40.1 h, respectively, at a dose of 25 nmol/kg (native Ex4 7.3 h). The results of this study show that combined dimerization and PEGylation are effective when applied to Ex4, and suggest that PEG-Di-Ex4 has considerable potential as a type 2 anti-diabetic agent. 相似文献
966.
Lee SE Yahng SA Cho BS Eom KS Kim YJ Kim HJ Lee S Cho SG Kim DW Lee JW Min WS Park CW Min CK 《Cytotherapy》2012,14(4):505-512
Background aimsThe aim of this study was to investigate the correlation between infused lymphocyte populations and lymphocyte subsets at engraftment, and the early clinical implications of lymphocyte subset recovery after autologous stem cell transplantation (ASCT) in multiple myeloma (MM).MethodsWe examined the lymphocyte populations of infused autografts and the lymphocyte subsets of peripheral blood at engraftment from 50 patients using flow cytometry. Each subset was grouped as low (below median) and high (above median) to examine the correlation with mucositis of grade 3 or more and the occurrence of infections and cytomegalovirus (CMV) reactivation.ResultsUsing Spearman correlation coefficients, we found that cell doses of infused CD8+ (P = 0.042) and CD19+ cells (P = 0.044) were significantly associated with the absolute lymphocyte count (ALC) at engraftment. The dose of infused CD34+ cells was not associated with the change of lymphocyte subsets except for an inverse correlation with CD4+ cells (P = 0.006). After adjusting for potential variables in univariate analysis, multivariate analyzes revealed that the lower ratio of infused CD4+ to CD8+ cells (P = 0.030) was an independent factor for severe mucositis. Of lymphocyte subsets at engraftment, a higher frequency of CD3+ (P = 0.024) and a lower frequency of CD56+ (P = 0.020) were independent predictors for infections after engraftment. A higher frequency of CD8+ cells (P = 0.041) and a lower ratio of CD4+ to CD8+ (P = 0.021) were independent predictors for CMV reactivation.ConclusionsOur data suggest that lymphocyte subset analysis of infused autograft and peripheral blood at engraftment may provide new predictors for early complications after ASCT in patient with MM. 相似文献
967.
Background
Certain facial configurations are believed to be associated with distinct affective meanings (i.e. basic facial expressions), and such associations are common across cultures (i.e. universality of facial expressions). However, recently, many studies suggest that various types of contextual information, rather than facial configuration itself, are important factor for facial emotion perception.Methodology/Principal Findings
To examine systematically how contextual information influences individuals’ facial emotion perception, the present study estimated direct observers’ perceptual thresholds for detecting negative facial expressions via a forced-choice psychophysical procedure using faces embedded in various emotional contexts. We additionally measured the individual differences in affective information-processing tendency (BIS/BAS) as a possible factor that may determine the extent to which contextual information on facial emotion perception is used. It was found that contextual information influenced observers'' perceptual thresholds for facial emotion. Importantly, individuals’ affective-information tendencies modulated the extent to which they incorporated context information into their facial emotion perceptions.Conclusions/Significance
The findings of this study suggest that facial emotion perception not only depends on facial configuration, but the context in which the face appears as well. This contextual influence appeared differently with individual’s characteristics of information processing. In summary, we conclude that individual character traits, as well as facial configuration and the context in which a face appears, need to be taken into consideration regarding facial emotional perception. 相似文献968.
Shin DW Cho J Kim YW Oh JH Kim SW Chung KW Lee WY Lee JE Guallar E Lee WC 《PloS one》2012,7(3):e33238
Background
Cancer surivors have limited knowledge about second primary cancer (SPC) screening and suboptimal rates of completion of screening practices for SPC. Our objective was to test the efficacy of an educational material on the knowledge, attitudes, and screening practices for SPC among cancer survivors.Methods
Randomized, controlled trial among 326 cancer survivors from 6 oncology care outpatient clinics in Korea. Patients were randomized to an intervention or an attention control group. The intervention was a photo-novel, culturally tailored to increase knowledge about SPC screening. Knowledge and attitudes regarding SPC screening were assessed two weeks after the intervention, and screening practices were assessed after one year.Results
At two weeks post-intervention, the average knowledge score was significantly higher in the intervention compared to the control group (0.81 vs. 0.75, P<0.01), with no significant difference in their attitude scores (2.64 vs. 2.57, P = 0.18). After 1 year of follow-up, the completion rate of all appropriate cancer screening was 47.2% in both intervention and control groups.Conclusion
While the educatinal material was effective for increasing knowledge of SPC screening, it did not promote cancer screening practice among cancer survivors. More effective interventions are needed to increase SPC screening rates in this population.Trial Registration
ClinicalTrial.gov NCT00948337相似文献969.
Jang BG Won SJ Kim JH Choi BY Lee MW Sohn M Song HK Suh SW 《Journal of trace elements in medicine and biology》2012,26(2-3):85-88
The excitatory amino acids glutamate and cysteine are actively transported into neurons from the extracellular space by the high affinity glutamate transporter EAAC1. The astrocyte glutamate transporters, GLT1 and GLAST, are the primary mediators of glutamate clearance. EAAC1 has a limited role in this function. However, uptake of cysteine into neurons via EAAC1 contributes to neuronal antioxidant function by providing cysteine substrate for glutathione synthesis. Mice in which the EAAC1 gene has been deleted were seen to have enhanced susceptibility to neuronal oxidative stress and developed brain atrophy and cognitive function decline with aging. The aim of the current study was to evaluate if EAAC1 confers protection against ischemic events. Young adult CD-1 wild-type or EAAC1(-/-) mice were subjected to 30 min of bilateral common carotid artery occlusion and evaluated for neuronal death and zinc translocation. The intensity of TSQ fluorescence in the cytoplasm of cortical neurons in the EAAC1(-/-) mice was significantly higher than wild-type mice, indicating that the cortical neurons of EAAC1(-/-) mice contain higher cytoplasmic concentrations of labile (or free) zinc. Zinc translocation into cortical neurons was also enhanced in EAAC1(-/-) mice. Three days after ischemia, Fluoro-Jade B staining revealed that EAAC1(-/-) mice had more than twice as many degenerating neurons as wild-type mice. N-acetylcysteine, a membrane-permeant cysteine pro-drug, normalized basal zinc levels, reduced TSQ (+) neurons and reduced ischemic neuronal death in the EAAC1(-/-) mice when delivered in a pre-treatment fashion. Taken together, this study implicates EAAC1-dependent cysteine uptake as an endogenous source of enhancing antioxidant function and zinc homeostasis in neurons in the ischemic brain. 相似文献
970.