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951.
Chan Kue Park Ki Seok Choo Ung Bae Jeon Seung Kug Baik Yong Woo Kim Tae Un Kim Chang Won Kim Yeon Ju Jeong Dong Wook Jeong Soo Jin Lim 《The international journal of cardiovascular imaging》2013,29(1):47-51
To compare vascular enhancement, image quality, and radiation dose of 128-slice dual-source CT venography (CTV) between an imaging setting of 120 kVp with low pitch, and a setting of 100 kVp combined with high pitch and automatic tube current modulation. A total of 100 patients with suspected deep vein thrombosis and varicose veins were divided into two groups: Group 1 [50 patients, 120 kVp, low pitch (0.6), and fixed 120 mA) and Group 2 (50 patients, 100 kVp, high pitch (3.0), and automatic tube current modulation]. Two radiologists, who were blinded to the image protocol, assessed vascular enhancement and image noise in the inferior vena cava (IVC), femoral vein, and popliteal vein. They also assigned an image quality score independently using a 5-point visual scale. Effective dose was estimated using the dose-length product (DLP). Group demographics, radiation dose, vascular enhancement, image noise, and image quality in the two groups were analyzed. Mean vascular enhancement of the IVC, femoral vein, and popliteal vein was significantly higher in group 2 than in group 1, and images in group 2 had significantly higher image noise. However, there were no significant differences in subjective image quality score of the IVC, femoral vein, and popliteal vein. The mean DLP in group 2 (402.10 ± 94.29 mGy cm) was significantly lower than that in group 1 (973.36 ± 63.20 mGy cm) (P < 0.001). Lower extremity CTV using 100 kVp, high pitch (3.0), and automatic tube current modulation improved vascular enhancement with acceptable image quality and low radiation dose. 相似文献
952.
Lee YJ Cho KH Kim MJ Smith DM Ho CS Jung KC Jin DI Park CS Jeon JT Lee JH 《International journal of immunogenetics》2008,35(4-5):333-334
Eight swine leucocyte antigen (SLA) gene (SLA-1, SLA-2, SLA-3, SLA-6, DRA, DRB1, DQA, DQB1) alleles were identified using sequence-based typing method in three Korean native pigs used for breeding at the National Institute of Animal Science in Korea. Six new alleles in class I genes and three new alleles in class II genes have been identified in this breed and can give valuable information for xenotransplantation and disease resistance. 相似文献
953.
Epstein-Barr virus (EBV) infection in vitro transforms primary B cells into continuously proliferating lymphoblastoid cell lines (LCLs) that have been widely used as a genomic resource for variety of immunological and genetic studies. However, the biochemical and biological characteristics that distinguish LCLs from the B cells have not been thoroughly investigated. Our proteomic approach showed that EBV infection induced changes in the profiles of tumor necrosis factor (TNF) signaling-related proteins in LCLs including heat shock protein family members TNF receptor-associated protein 1 (TRAP-1), heat shock 70-kDa protein 9 (HSPA9)) and superoxide dismutase 2 (SOD2). In addition, our literature co-occurrence study placed TNF at the center of a gene cluster network of differentially expressed proteins in LCLs. This study suggested that deregulation of TNF signaling pathway could contribute to the cellular transformation and immortalization of the EBV-infected B cells. 相似文献
954.
Lactobacillus casei suppresses experimental arthritis by down-regulating T helper 1 effector functions 总被引:10,自引:0,他引:10
So JS Kwon HK Lee CG Yi HJ Park JA Lim SY Hwang KC Jeon YH Im SH 《Molecular immunology》2008,45(9):2690-2699
Although the beneficial effects of probiotics on wide variety of diseases have been shown, little is known about how probiotics modulate the immune system. In this study we elucidated the underlying mechanisms how Lactobacillus casei (L. casei) protects against rheumatoid arthritis (RA) progression by investigating the effector functions of CD4(+) T cells. Oral administration of L. casei suppressed collagen-induced arthritis (CIA) and reduced paw swelling, lymphocyte infiltration and destruction of cartilage tissue. L. casei administration reduced type II collagen (CII)-reactive proinflammatory molecules (IL-1beta, IL-2, IL-6, IL-12, IL-17, IFN-gamma, TNF-alpha and Cox-2) by CD4(+) T cells. L. casei administration also reduced translocation of NF-kappaB into nucleus and CII-reactive Th1-type IgG isotypes IgG2a and IgG2b, while up-regulating immunoregulatory IL-10 levels. Our results suggest that oral administration of L. casei suppresses the type II collagen-reactive effector function of Th1-type cellular and humoral immune responses in arthritic inflammation. 相似文献
955.
Jeon RJ Hellen A Matvienko A Mandelis A Abrams SH Amaechi BT 《Journal of biomedical optics》2008,13(3):034025
Artificially created demineralized and remineralized carious lesions on the root and enamel of human teeth were examined by photothermal radiometry (PTR) and modulated luminescence (LUM). Fourteen extracted human teeth were used and a lesion was created on a 1 mmx4 mm rectangular window, spanning root to enamel, using a lactic acid-based acidified gel to demineralize the tooth surface. The lesion was then exposed to a remineralization solution. Each sample was examined with PTR/LUM on the root and enamel before and after treatment at times from 1 to 10 (5 on root) days of demineralization and 2 to 10 days of remineralization. Ten-day (5 on root) demineralized samples were remineralized. After completing all the experiments, transverse microradiography (TMR) analysis was performed to compare and correlate the PTR/LUM signals to the depth of lesions and mineral losses. The PTR and LUM amplitudes and phases showed gradual and consistent changes with treatment time. In this study, TMR showed good correlation coefficients with PTR and LUM. It was also found that the length of the treatment time did not correlate very well to any technique, PTR/LUM or TMR, which implies a significant degree of inhomogeneity of the demireralization and remineralization rates in each and every tooth. 相似文献
956.
Aims: Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease with various genetic alterations. The aim was to investigate MYC , Bcl-2 and Bcl-6 translocations and copy number changes in adult DLBCLs to evaluate their clinicopathological features and prognostic implications.
Methods and results: Gene status was examined using fluorescence in situ hybridization (FISH), and the results were analysed in the context of germinal centre B-cell (GCB) and non-GCB type of DLBCL based on immunohistochemistry. MYC translocation was observed in 9% (14 of 156), and an increased copy number (ICN) in 7.1% (11 of 156). MYC translocation was more common in GCB type (22%) than in non-GCB type (4.9%), and associated with advanced International Prognostic Index (IPI). MYC aberration, i.e. translocation or increased copy number (ICN), was significantly associated with shorter overall survival, especially for the GCB type. Bcl-2 translocation was rare (3.4%, five of 145), and ICN was observed in 11.7% (17 of 145), more frequently in non-GCB type (16%) than in GCB type (2.5%). Bcl-2 aberration tended to have an adverse effect on survival. In multivariate analysis, MYC ICN was an independent poor prognostic factor.
Conclusions: Analyses of MYC and Bcl-2 status, i.e. translocation and ICN, in the context of DLBCL phenotype might help predict prognosis and determine therapeutic strategies. 相似文献
Methods and results: Gene status was examined using fluorescence in situ hybridization (FISH), and the results were analysed in the context of germinal centre B-cell (GCB) and non-GCB type of DLBCL based on immunohistochemistry. MYC translocation was observed in 9% (14 of 156), and an increased copy number (ICN) in 7.1% (11 of 156). MYC translocation was more common in GCB type (22%) than in non-GCB type (4.9%), and associated with advanced International Prognostic Index (IPI). MYC aberration, i.e. translocation or increased copy number (ICN), was significantly associated with shorter overall survival, especially for the GCB type. Bcl-2 translocation was rare (3.4%, five of 145), and ICN was observed in 11.7% (17 of 145), more frequently in non-GCB type (16%) than in GCB type (2.5%). Bcl-2 aberration tended to have an adverse effect on survival. In multivariate analysis, MYC ICN was an independent poor prognostic factor.
Conclusions: Analyses of MYC and Bcl-2 status, i.e. translocation and ICN, in the context of DLBCL phenotype might help predict prognosis and determine therapeutic strategies. 相似文献
957.
PURPOSE: Endobronchial tuberculosis (EBTB) presenting as right middle lobe syndrome (RMLS) is an uncommon clinical condition. We investigated the clinical characteristics in patients with EBTB presenting as RMLS. PATIENTS AND METHODS: We retrospectively reviewed the records of 22 patients with EBTB presenting as RMLS who were diagnosed at our hospital from 2003 to 2006. RESULTS: Its occurrence was more common in females than males (F, 18; M, 4). The mean age was 70.3 +/- 8.5 years, and 17 patients were above the age of 65 years. Cough with sputum was the most common manifestation and 2 patients were asymptomatic. In bronchoscopic analysis, the most common finding was edematous-type EBTB, which was found in 15 patients, followed by actively caseating type in 6 and tumorous type in 1. Acid-fast bacilli (AFB) staining for bronchial washing fluid was positive in only 5 patients: 1 with edematous type and 4 with actively caseating type. Bronchoscopic biopsy showed chronic granulomatous inflammation in 16 patients. Follow-up chest X-ray after treatment showed complete disappearance of the lesion in 2 patients, more than 50% improvement in 5, less than 50% improvement in 5, and no change of lesion in 4. CONCLUSION: Edematous-type EBTB was the most common type of EBTB presenting as RMLS, and it usually occurred in elderly patients. Culturing for mycobacterium and histologic examination by bronchoscopy are necessary for proper diagnosis in these patients. 相似文献
958.
To explore the epidemiological link between infectious bursal disease virus (IBDV) in wild birds and domestic chickens in Korea, we examined 107 free-living wild birds, representing 7 species, that were found dead of apparent natural causes in Korea over the past two years for the presence of IBDV. Five birds were tested positive for IBDV by RT-PCR assay: black-billed magpie (n=1), mallard duck (n=2), bean goose (n=1) and white-fronted goose (n=1). IBDV was isolated from RT-PCR-positive tissues following chicken embryo inoculation. Sequence analysis of the VP2 gene indicated that all of the isolates from the wild birds encode amino acids A222, I242, I256, I294 and S299 of VP2, which are conserved among strains of very virulent IBDV (vvIBDV). Phylogenetic analysis revealed that the wild bird IBDV isolates are closely related to strains of vvIBDV. An IBDV isolate from a magpie showed 60% mortality in SPF chickens and severe bursal atrophy. The epidemiological implications of IBDV in free-living wild birds are discussed. To our knowledge, this is the first report of vvIBDV in free-living wild birds. 相似文献
959.
Lee KS Han TH Jo JY Kang G Lee SY Ryu PD Im JH Jeon BH Park JB 《Neuroscience letters》2008,439(2):138-142
Activation of serotonin (5-hydroxytryptamine, 5-HT) receptors produces various autonomic and neuroendocrine responses in the hypothalamic paraventricular nucleus (PVN), including increased blood pressure and heart rate. However, the role(s) of 5-HT on the local GABA synaptic circuit have not been well understood in the PVN, where the inhibitory neurotransmitter GABA plays a key role in the modulation of sympathoexcitatory outflow. In the present study, we examined the effects of 5-HT on GABA synaptic transmission in presympathetic PVN neurons projecting to spinal cord using patch-clamp electrophysiology combined with tract-tracing techniques. Bath application of 5-HT (0.01-100 microM) reversibly decreased the frequency of spontaneous GABAergic inhibitory postsynaptic currents (sIPSC) in a concentration dependent manner (IC50, 0.07 microM), with no significant changes in the amplitudes and decay kinetics of sIPSC. The sIPSC inhibition of 5-HT was mimicked by 5-HT1A agonist, 8-OH-DPAT (8-hydroxy-2(di-n-propylamino)tetralin, 10 microM), and blocked by 5-HT1A antagonist WAY-100635 but not by 5-HT1B antagonist SB224289. 5-HT also reduced the frequency of miniature IPSC (mIPSC) (2.59+/-0.51 Hz, control vs. 1.25+/-0.31 Hz, 5-HT, n=16) in similar extent with 5-HT induced reduction of sIPSC frequency (sIPSCs, 55.8+/-6.2%, n=11 vs. mIPSCs, 52.30+/-5.85%, n=16; p>0.5). All together, our results indicate that 5-HT can inhibit presynaptic GABA release via presynaptic 5-HT1A receptors in presympathetic PVN neurons projecting to spinal cord. 相似文献
960.
Joo KM Kim SY Jin X Song SY Kong DS Lee JI Jeon JW Kim MH Kang BG Jung Y Jin J Hong SC Park WY Lee DS Kim H Nam DH 《Laboratory investigation; a journal of technical methods and pathology》2008,88(8):808-815
A number of recent reports have demonstrated that only CD133-positive cancer cells of glioblastoma multiforme (GBM) have tumor-initiating potential. These findings raise an attractive hypothesis that GBMs can be cured by eradicating CD133-positive cancer stem cells (CSCs), which are a small portion of GBM cells. However, as GBMs are known to possess various genetic alterations, GBMs might harbor heterogeneous CSCs with different genetic alterations. Here, we compared the clinical characteristics of two GBM patient groups divided according to CD133-positive cell ratios. The CD133-low GBMs showed more invasive growth and gene expression profiles characteristic of mesenchymal or proliferative subtypes, whereas the CD133-high GBMs showed features of cortical and well-demarcated tumors and gene expressions typical of proneuronal subtype. Both CD133-positive and CD133-negative cells purified from four out of six GBM patients produced typical GBM tumor masses in NOD-SCID brains, whereas brain mass from CD133-negative cells showed more proliferative and angiogenic features compared to that from CD133-positive cells. Our results suggest, in contrast to previous reports that only CD133-positive cells of GBMs can initiate tumor formation in vivo CD133-negative cells also possess tumor-initiating potential, which is indicative of complexity in the identification of cancer cells for therapeutic targeting. 相似文献