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151.
Jae-Yoo Choi Yong-Dae Gwon Jeong-Ki Kim Yeon-Dong Cho Yoon-Ki Heo Han-Sam Cho Tae-Jin Choi Ha-Ryoung Poo Yu-Kyoung Oh Young Bong Kim 《PloS one》2013,8(11)
Despite the advantages of DNA vaccines, overcoming their lower efficacy relative to that of conventional vaccines remains a challenge. Here, we constructed a human endogenous retrovirus (HERV) envelope-coated, nonreplicable, baculovirus-based HA vaccine against swine influenza A/California/04/2009(H1N1) hemagglutin (HA) (AcHERV-sH1N1-HA) as an alternative to conventional vaccines and evaluated its efficacy in two strains of mice, BALB/c and C57BL/6. A commercially available, killed virus vaccine was used as a positive control. Mice were intramuscularly administered AcHERV-sH1N1-HA or the commercial vaccine and subsequently given two booster injections. Compared with the commercial vaccine, AcHERV-sH1N1-HA induced significantly higher levels of cellular immune responses in both BALB/c and C57BL/6 mice. Unlike cellular immune responses, humoral immune responses depended on the strain of mice. Following immunization with AcHERV-sH1N1-HA, C57BL/6 mice showed HA-specific IgG titers 10- to 100-fold lower than those of BALB/c mice. In line with the different levels of humoral immune responses, the survival of immunized mice after intranasal challenge with sH1N1 virus (A/California/04/2009) depended on the strain. After challenge with 10-times the median lethal dose (MLD50) of sH1N1 virus, 100% of BALB/c mice immunized with the commercial vaccine or AcHERV-sH1N1-HA survived. In contrast, C57BL/6 mice immunized with AcHERV-sH1N1-HA or the commercial vaccine showed 60% and 70% survival respectively, after challenge with sH1N1 virus. In all mice, virus titers and results of histological analyses of lung tissues were consistent with the survival data. Our results indicate the importance of humoral immune response as a major defense system against influenza viral infection. Moreover, the complete survival of BALB/c mice immunized with AcHERV-sH1N1-HA after challenge with sH1N1 virus suggests the potential of baculoviral vector-based vaccines to achieve an efficacy comparable to that of killed virus vaccines. 相似文献
152.
Objective
This study was designed to investigate the revised and short version of the smartphone addiction scale and the proof of its validity in adolescents. In addition, it suggested cutting off the values by gender in order to determine smartphone addiction and elaborate the characteristics of smartphone usage in adolescents.Method
A set of questionnaires were provided to a total of 540 selected participants from April to May of 2013. The participants consisted of 343 boys and 197 girls, and their average age was 14.5 years old. The content validity was performed on a selection of shortened items, while an internal-consistency test was conducted for the verification of its reliability. The concurrent validity was confirmed using SAS, SAPS and KS-scale. Receiver operating characteristics analysis was conducted to suggest cut-off.Results
The 10 final questions were selected using content validity. The internal consistency and concurrent validity of SAS were verified with a Cronbach''s alpha of 0.911. The SAS-SV was significantly correlated with the SAS, SAPS and KS-scale. The SAS-SV scores of gender (p<.001) and self-evaluation of smartphone addiction (p<.001) showed significant difference. The ROC analysis results showed an area under a curve (AUC) value of 0.963(0.888–1.000), a cut-off value of 31, sensitivity value of 0.867 and specificity value of 0.893 in boys while an AUC value of 0.947(0.887–1.000), a cut-off value of 33, sensitivity value of 0.875, and a specificity value of 0.886 in girls.Conclusions
The SAS-SV showed good reliability and validity for the assessment of smartphone addiction. The smartphone addiction scale short version, which was developed and validated in this study, could be used efficiently for the evaluation of smartphone addiction in community and research areas. 相似文献153.
Huiyun Seo In-Seon Lee Jae Eun Park Sung Goo Park Do Hee Lee Byoung Chul Park Sayeon Cho 《PloS one》2013,8(11)
Protein tyrosine phosphatases play key roles in a diverse range of cellular processes such as differentiation, cell proliferation, apoptosis, immunological signaling, and cytoskeletal function. Protein tyrosine phosphatase non-receptor type 7 (PTPN7), a member of the phosphatase family, specifically inactivates mitogen-activated protein kinases (MAPKs). Here, we report that PTPN7 acts as a regulator of pro-inflammatory TNF-α production in RAW 264.7 cells that are stimulated with lipopolysaccharide (LPS) that acts as an endotoxin and elicits strong immune responses in animals. Stimulation of RAW 264.7 cells with LPS leads to a transient decrease in the levels of PTPN7 mRNA and protein. The overexpression of PTPN7 inhibits LPS-stimulated production of TNF-α. In addition, small interfering RNA (siRNA) analysis showed that knock-down of PTPN7 in RAW 264.7 cells increased TNF-α production. PTPN7 has a negative regulatory function to extracellular signal regulated kinase 1/2 (ERK1/2) and p38 that increase LPS-induced TNF-α production in macrophages. Thus, our data presents PTPN7 as a negative regulator of TNF-α expression and the inflammatory response in macrophages. 相似文献
154.
Armon Sharei Nahyun Cho Shirley Mao Emily Jackson Roberta Poceviciute Andrea Adamo Janet Zoldan Robert Langer Klavs F Jensen 《Journal of visualized experiments : JoVE》2013,(81)
Rapid mechanical deformation of cells has emerged as a promising, vector-free method for intracellular delivery of macromolecules and nanomaterials. This technology has shown potential in addressing previously challenging applications; including, delivery to primary immune cells, cell reprogramming, carbon nanotube, and quantum dot delivery. This vector-free microfluidic platform relies on mechanical disruption of the cell membrane to facilitate cytosolic delivery of the target material. Herein, we describe the detailed method of use for these microfluidic devices including, device assembly, cell preparation, and system operation. This delivery approach requires a brief optimization of device type and operating conditions for previously unreported applications. The provided instructions are generalizable to most cell types and delivery materials as this system does not require specialized buffers or chemical modification/conjugation steps. This work also provides recommendations on how to improve device performance and trouble-shoot potential issues related to clogging, low delivery efficiencies, and cell viability. 相似文献
155.
Haegyeom Kim Min‐Young Cho Mok‐Hwa Kim Kyu‐Young Park Hyeokjo Gwon Yunsung Lee Kwang Chul Roh Kisuk Kang 《Liver Transplantation》2013,3(11):1500-1506
A hybrid supercapacitor with high energy and power densities is reported. It comprises a composite anode of anatase TiO2 and reduced graphene oxide and an activated carbon cathode in a non‐aqueous electrolyte. While intercalation compounds can provide high energy typically at the expense of power, the anatase TiO2 nanoparticles are able to sustain both high energy and power in the hybrid supercapacitor. At a voltage range from 1.0 to 3.0 V, 42 W h kg?1 of energy is achieved at 800 W kg?1. Even at a 4‐s charge/discharge rate, an energy density as high as 8.9 W h kg?1 can be retained. The high energy and power of this hybrid supercapacitor bridges the gap between conventional batteries with high energy and low power and supercapacitors with high power and low energy. 相似文献
156.
Se-Kwon Moon Julia Lee Hyohak Song Jung-Hee Cho Gi-Wook Choi Doyoung Seung 《Bioprocess and biosystems engineering》2013,36(5):547-554
In this study, an ethanol fermentation waste (EFW) was characterized for use as an alternative to yeast extract for bulk fermentation processes. EFW generated from a commercial plant in which ethanol is produced from cassava/rice/wheat/barley starch mixtures using Saccharomyces cerevisiae was used for lactic acid production by Lactobacillus paracasei. The effects of temperature, pH, and duration on the autolysis of an ethanol fermentation broth (EFB) were also investigated. The distilled EFW (DEFW) contained significant amounts of soluble proteins (2.91 g/l), nitrogen (0.47 g/l), and amino acids (24.1 mg/l). The autolysis of the EFB under optimum conditions released twice as much amino acids than in the DEFW. Batch fermentation in the DEFW increased the final lactic acid concentration, overall lactic acid productivity, and lactic acid yield on glucose by 17, 41, and 14 %, respectively, in comparison with those from comparable fermentation in a lactobacillus growth medium (LGM) that contained 2 g/l yeast extract. Furthermore, the overall lactic acid productivity in the autolyzed then distilled EFW (ADEFW) was 80 and 27 % higher than in the LGM and DEFW, respectively. 相似文献
157.
Clara E. Cho Diana Sánchez-Hernández Sandra A. Reza-López Pedro S.P. Huot Young-In Kim G. Harvey Anderson 《Epigenetics》2013,8(7):710-719
Our aim was to comprehensively analyze promoter hypermethylation of a panel of novel and known methylation markers for thyroid neoplasms and to establish their relationship with BRAF mutation and clinicopathologic parameters of thyroid cancer. A cohort of thyroid tumors, consisting of 44 cancers and 44 benign thyroid lesions, as well as 15 samples of adjacent normal thyroid tissue, was evaluated for BRAF mutation and promoter hypermethylation. Genes for quantitative methylation specific PCR (QMSP) were selected by a candidate gene approach. Twenty-two genes were tested: TSHR, RASSF1A, RARβ2, DAPK, hMLH1, ATM, S100, p16, CTNNB1, GSTP1, CALCA, TIMP3, TGFßR2, THBS1, MINT1, CTNNB1, MT1G, PAK3, NISCH, DCC, AIM1 and KIF1A. The PCR-based “mutector assay” was used to detect BRAF mutation. All p values reported are two sided. Considerable overlap was seen in the methylation markers among the different tissue groups. Significantly higher methylation frequency and level were observed for KIF1A and RARß2 in cancer samples compared with benign tumors. A negative correlation between BRAF mutation and RASSF1A methylation, and a positive correlation with RARß2 methylation were observed in accordance with previous results. In addition, positive correlation with TIMP3 and a marginal correlation with DCC methylation were observed. The present study constitutes a comprehensive promoter methylation profile of thyroid neoplasia and shows that results must be analyzed in a tissue-specific manner to identify clinically useful methylation markers. Integration of genetic and epigenetic changes in thyroid cancer will help identify relevant biologic pathways that drive its development. 相似文献
158.
Su-Jin Park Hyun-Sook Bae Young-Sik Cho Soon-Ryun Lim Seung-Ae Kang Joo-Cheol Park 《Journal of molecular histology》2013,44(1):65-73
Bone remodeling, the selective deposition and resorption of bone, is an important cause of tooth eruption. During tooth eruption, reduced enamel epithelia of the enamel organ interact with follicle cells to recruit osteoclasts for bone remodeling. However, little is known about the relationship between cellular activity of reduced enamel epithelium and bone resorption during tooth eruption. The purpose of this study was to investigate the effect of apoptosis in reduced enamel epithelium on osteoclastogenesis and its implications for bone resorption. We have analyzed erupting mandibular molars in mice by TdT-mediated dUTP-biotin nick end labeling assay, tartrate-resistant acid phosphatase (TRAP) staining, and immunohistochemistry. TRAP-positive cells were detected in the osteoclasts near both the buccal and lingual sides of tooth socket at postnatal day 0 (PN0). They significantly increased until PN3 and decreased thereafter as the tooth erupted. Interestingly, apoptosis was barely detected in the reduced enamel epithelium at PN3 but clearly at PN7. A few apoptotic cells were also investigated within the dental follicle surrounding developing tooth at PN7 and PN10. We observed apoptotic osteoblast-lineage cells along the inner margin of alveolar bone facing the buccal cusp and at the base of the bony crypt at PN3 decreasing until PN10. In contrast, expression levels of bone sialoprotein increased at PN10 compared to levels at PN3. These results suggest that apoptosis of reduced enamel epithelium resulted in a reduction of osteoclast activity and of bone resorption mediated by dental follicle during tooth eruption. 相似文献
159.
Hyunsoo Kim Taesoo Kim Byung-Chul Jeong Il-Taeg Cho Daehee Han Noriko Takegahara Takako Negishi-Koga Hiroshi Takayanagi Jae Hee Lee Jai-Yoon Sul Vikram Prasad Seoung Hoon Lee Yongwon Choi 《Cell metabolism》2013,17(2):249-260
Highlights? Tmem64-deficient mice show increased bone volume ? Tmem64 deficiency reduces [Ca2+]i oscillation in response to RANKL stimulation ? Tmem64 interacts with SERCA2 ? Tmem64 positively regulates osteoclast formation via SERCA2/Ca2+ signaling 相似文献
160.
Hyun-Ju Cho Hyun-Jai Cho Ho-Jae Lee Myung-Kang Song Ji-Yun Seo Yeon-Hee Bae Ju-Young Kim Hae-Young Lee Whal Lee Bon-Kwon Koo Byung-Hee Oh Young-Bae Park Hyo-Soo Kim 《PLoS biology》2013,11(4)
Vascular calcification is an advanced feature of atherosclerosis for which no effective therapy is available. To investigate the modulation or reversal of calcification, we identified calcifying progenitor cells and investigated their calcifying/decalcifying potentials. Cells from the aortas of mice were sorted into four groups using Sca-1 and PDGFRα markers. Sca-1+ (Sca-1+/PDGFRα+ and Sca-1+/PDGFRα−) progenitor cells exhibited greater osteoblastic differentiation potentials than Sca-1− (Sca-1−/PDGFRα+ and Sca-1−/PDGFRα−) progenitor cells. Among Sca-1+ progenitor populations, Sca-1+/PDGFRα− cells possessed bidirectional differentiation potentials towards both osteoblastic and osteoclastic lineages, whereas Sca-1+/PDGFRα+ cells differentiated into an osteoblastic lineage unidirectionally. When treated with a peroxisome proliferator activated receptor γ (PPARγ) agonist, Sca-1+/PDGFRα− cells preferentially differentiated into osteoclast-like cells. Sca-1+ progenitor cells in the artery originated from the bone marrow (BM) and could be clonally expanded. Vessel-resident BM-derived Sca-1+ calcifying progenitor cells displayed nonhematopoietic, mesenchymal characteristics. To evaluate the modulation of in vivo calcification, we established models of ectopic and atherosclerotic calcification. Computed tomography indicated that Sca-1+ progenitor cells increased the volume and calcium scores of ectopic calcification. However, Sca-1+/PDGFRα− cells treated with a PPARγ agonist decreased bone formation 2-fold compared with untreated cells. Systemic infusion of Sca-1+/PDGFRα− cells into Apoe−/− mice increased the severity of calcified atherosclerotic plaques. However, Sca-1+/PDGFRα− cells in which PPARγ was activated displayed markedly decreased plaque severity. Immunofluorescent staining indicated that Sca-1+/PDGFRα− cells mainly expressed osteocalcin; however, activation of PPARγ triggered receptor activator for nuclear factor-κB (RANK) expression, indicating their bidirectional fate in vivo. These findings suggest that a subtype of BM-derived and vessel-resident progenitor cells offer a therapeutic target for the prevention of vascular calcification and that PPARγ activation may be an option to reverse calcification. 相似文献