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Kim CK, Jang SM, Park BK. Diffusion tensor imaging of normal prostate at 3 T: effect of number of diffusion-encoding directions on quantitation and image quality. Br J Radiol 2011; 85:e279-83. [PMID: 21896666 DOI: 10.1259/bjr/21316959] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
OBJECTIVE The purpose of this study was to prospectively investigate differences of diffusion tensor imaging (DTI) using a different number of diffusion-encoding directions and to evaluate the feasibility of tractography in healthy prostate at 3 T. METHOD 12 healthy volunteers underwent DTI with single-shot echo-planar imaging at 3 T using a phased-array coil. Diffusion gradients of each DTI were applied in 6 (Group 1), 15 (Group 2) and 32 (Group 3) non-collinear directions. For each group, the mean apparent diffusion coefficient (ADC), fractional anisotrophy (FA) and signal-to-noise ratio (SNR) were measured in the peripheral zone (PZ) and central gland (CG). The quality of diffusion-weighted and tractographic images were also evaluated. RESULTS In all three groups, the mean ADC value of the CG was statistically lower than that of the PZ (p<0.01) and the mean FA value of the CG was statistically greater than that of the PZ (p<0.01). For the mean FA value of the CG, no statistical difference was seen among the three groups (p=0.052). However, the mean FA value of the PZ showed a statistical difference among the three groups (p=0.035). No significant difference in SNR values was seen among the three groups (p>0.05). Imaging quality of diffusion-weighted tractographic images was rated as satisfactory or better in all three groups and was similar among the three groups. CONCLUSION In conclusion, prostate DTI at 3 T was feasible with different numbers of diffusion-encoding directions. The number of diffusion-encoding directions did not have a significant effect on imaging quality.
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Hwang YH, Song IB, Lee HK, Kim TW, Kim MS, Lim JH, Park BK, Yun HI. Pharmacokinetics and bioavailability of cefquinome in rabbits following intravenous and intramuscular administration. J Vet Pharmacol Ther 2011; 34:618-20. [PMID: 21615754 DOI: 10.1111/j.1365-2885.2011.01289.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Park EK, Lee EJ, Lee SH, Koo KH, Sung JY, Hwang EH, Park JH, Kim CW, Jeong KC, Park BK, Kim YN. Induction of apoptosis by the ginsenoside Rh2 by internalization of lipid rafts and caveolae and inactivation of Akt. Br J Pharmacol 2010; 160:1212-23. [PMID: 20590613 DOI: 10.1111/j.1476-5381.2010.00768.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND AND PURPOSE Lipid rafts and caveolae are membrane microdomains with important roles in cell survival signalling involving the Akt pathway. Cholesterol is important for the structure and function of these microdomains. The ginsenoside Rh2 exhibits anti-tumour activity. Because Rh2 is structurally similar to cholesterol, we investigated the possibility that Rh2 exerted its anti-tumour effect by modulating rafts and caveolae. EXPERIMENTAL APPROACH A431 cells (human epidermoid carcinoma cell line) were treated with Rh2 and the effects on cell apoptosis, raft localization and Akt activation measured. We also examined the effects of over-expression of Akt and active-Akt on Rh2-induced cell death. KEY RESULTS Rh2 induced apoptosis concentration- and time-dependently. Rh2 reduced the levels of rafts and caveolae in the plasma membrane and increased their internalization. Furthermore, Akt activity was decreased and consequently, Akt-dependent phosphorylation of Bad, a pro-survival protein, was decreased whereas the pro-apoptotic proteins, Bim and Bax, were increased upon Rh2 treatment. Unlike microdomain internalization induce by cholesterol depletion, Rh2-mediated internalization of rafts and caveolae was not reversed by cholesterol addition. Also, cholesterol addition did not restore Akt activation or rescue cells from Rh2-induced cell death. Rh2-induced cell death was attenuated in MDA-MB-231 cells over-expressing either wild-type or dominant-active Akt. CONCLUSIONS AND IMPLICATIONS Rh2 induced internalization of rafts and caveolae, leading to Akt inactivation, and ultimately apoptosis. Because elevated levels of membrane rafts and caveolae, and Akt activation have been correlated with cancer development, internalization of these microdomains by Rh2 could potentially be used as an anti-cancer therapy.
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Nam H, Huh SJ, Park W, Bae DS, Kim BG, Lee JH, Kim CK, Park BK. Prognostic significance of MRI-detected bladder muscle and/or serosal invasion in patients with cervical cancer treated with radiotherapy. Br J Radiol 2010. [DOI: 10.1259/bjr/6646798] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Park BK, Laverty H, Srivastava A, Antoine DJ, Naisbitt D, Williams DP. Drug bioactivation and protein adduct formation in the pathogenesis of drug-induced toxicity. Chem Biol Interact 2010; 192:30-6. [PMID: 20846520 DOI: 10.1016/j.cbi.2010.09.011] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 09/06/2010] [Accepted: 09/07/2010] [Indexed: 02/06/2023]
Abstract
Adverse drug reactions (ADRs) remain a major complication of drug therapy and can be classified as 'on-target' or 'off-target' (idiosyncratic) reactions. On-target reactions can be predicted from the known primary or secondary pharmacology of the drug and often represent an exaggeration of the pharmacological effect of the drug. In contrast, off-target adverse reactions cannot be predicted from knowledge of the basic pharmacology of the drug. The exact mechanisms of idiosyncratic drug reactions are still unclear; however it is believed that they can be initiated by chemically reactive drug metabolites. It is well known that xenobiotics can undergo metabolic bioactivation reactions which have the potential to cause cellular stress and damage. Bioactivation of drugs is thought to have the potential of initiating covalent linkages between cellular protein and drugs which can be recognised by the adaptive immune system in the absence of detectable cellular stress. This process cannot yet be predicted in pre-clinical models or discovered in clinical trials. Because of this hazard perception, the formation of chemically reactive metabolites in early drug discovery remains a serious impediment to the development of new medicines and can lead to withdrawal of an otherwise effective therapeutic agent. The fear of such reactions occurring at the post-licensing stage - when such problems first become evident - is a major contribution to drug attrition. The first step towards such methodology has been the development of chemically reactive metabolite screens. The chemical basis of drug bioactivation can usually be rationalised and synthetic strategies put in place to prevent such bioactivation. However, there is no simple correlation between drug bioactivation in vitro and adverse drug reactions in the clinic. Such a chemical approach is clearly limited by the facts that (a) not all drugs that can undergo bioactivation by human drug-metabolising enzymes are associated with hypersensitivity in the clinic and (b) drug bioactivation may not always be a mandatory step in drug hypersensitivity. To predict such reactions in early drug development, it will require an integrated understanding of the chemical, immunological and genetic basis of adverse drug reactions in patients, which in turn will depend on the development of novel in vitro experimental systems.
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Nam H, Huh SJ, Park W, Bae DS, Kim BG, Lee JH, Kim CK, Park BK. Prognostic significance of MRI-detected bladder muscle and/or serosal invasion in patients with cervical cancer treated with radiotherapy. THE BRITISH JOURNAL OF RADIOLOGY 2010; 83:868-73. [PMID: 20846984 DOI: 10.1259/bjr/66646798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In cervical cancer, the prognostic significance of bladder wall invasion on MRI without pathological evidence of mucosal invasion is not known. From 454 consecutive patients with cervical cancer who were treated with radiation, we reviewed images and analysed the outcome of 92 patients with the Federation of International Gynecology and Obstetrics (FIGO) stage IIIB-IVA. We analysed the patients in three groups, normal, wall (muscle and/or serosal) invasion and mucosal invasion, according to the findings on the MRI. Kaplan-Meier life table analysis and the log-rank test were used to assess the survival rates and differences according to prognostic factors. MRI detected abnormalities in the bladder wall in 42 patients (45.6%): wall invasion in 24 and mucosal invasion in 18. 5 of 18 patients, suspected on MRI to have mucosal invasion, showed no pathological evidence of mucosal invasion. Median follow-up period was 34 months. 3-year cause-specific survival (CSS) in the normal group compared with the wall invasion group was 76.2% vs 71.4% (p = 0.48). 3-year CSS for the wall invasion group compared with the mucosal invasion group was 71.4% vs 54.3% (p = 0.04). Mucosal invasion on MRI (p = 0.03) and concurrent chemoradiotherapy (p = 0.01) was significant for CSS. The prognosis for patients with cervical cancer with evidence of muscle and/or serosal invasion of the bladder on MRI may not differ from that for patients without abnormality on MRI. In patients with the MRI finding of bladder mucosal invasion, further studies should be conducted regarding the role of cystoscopy to determine the need for pathological confirmation.
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Kim SJ, Yoon JS, Park BK, Won SJ. Superior mesenteric artery syndrome in a tetraplegic patient, 11 years after a spinal cord injury: a case report. Spinal Cord 2010; 48:838-9. [DOI: 10.1038/sc.2010.24] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Lee SH, Yoo KH, Sung KW, Koo HH, Kwon YJ, Kwon MM, Park HJ, Park BK, Kim YY, Park JA, Im HJ, Seo JJ, Kang HJ, Shin HY, Ahn HS. Hepatic veno-occlusive disease in children after hematopoietic stem cell transplantation: incidence, risk factors, and outcome. Bone Marrow Transplant 2009; 45:1287-93. [PMID: 20010866 DOI: 10.1038/bmt.2009.349] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Four hundred and sixty-seven hematopoietic stem cell transplantations (HSCTs) (217 autologous and 250 allogeneic HSCT) were performed in 374 children at four pediatric HSCT centers in Korea from January 2005 to December 2007. Among 467 transplants, veno-occlusive disease (VOD) developed in 72 transplants (15.4%) at a median of 10 days after HSCT. Multivariate analysis showed that BU or TBI-containing regimen (P=0.002), VOD prophylaxis without lipo-prostaglandin E1 (PGE1) (P=0.012), number of previous HSCT (P=0.014), and pretransplant serum ferritin (P=0.018) were independent risk factors for developing VOD. Mean serum ferritin levels were significantly higher in HSCT with VOD (2109.6+/-2842.5 ng/ml) than in HSCT without VOD (1315.9+/-1094.4 ng/ml) (P<0.001). The relative risk of death within 100 days of HSCT in transplants with VOD compared with transplants without VOD was 3.39 (confidence interval: 1.78-6.45). Our results suggest that lipo-PGE1 might have a protective effect against the development of VOD, and pretransplant serum ferritin could act as a risk factor for VOD. A larger prospective study is needed to confirm a possible role of lipo-PGE1 and iron chelation therapy in reducing the incidence of VOD.
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Antoine DJ, Mercer AE, Williams DP, Park BK. Mechanism-based bioanalysis and biomarkers for hepatic chemical stress. Xenobiotica 2009; 39:565-77. [PMID: 19621999 DOI: 10.1080/00498250903046993] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Adverse drug reactions, in particular drug-induced hepatotoxicity, represent a major challenge for clinicians and an impediment to safe drug development. Novel blood or urinary biomarkers of chemically-induced hepatic stress also hold great potential to provide information about pathways leading to cell death within tissues. The earlier pre-clinical identification of potential hepatotoxins and non-invasive diagnosis of susceptible patients, prior to overt liver disease is an important goal. Moreover, the identification, validation and qualification of biomarkers that have in vitro, in vivo and clinical transferability can assist bridging studies and accelerate the pace of drug development. Drug-induced chemical stress is a multi-factorial process, the kinetics of the interaction between the hepatotoxin and the cellular macromolecules are crucially important as different biomarkers will appear over time. The sensitivity of the bioanalytical techniques used to detect biological and chemical biomarkers underpins the usefulness of the marker in question. An integrated analysis of the biochemical, molecular and cellular events provides an understanding of biological (host) factors which ultimately determine the balance between xenobiotic detoxification, adaptation and liver injury. The aim of this review is to summarise the potential of novel mechanism-based biomarkers of hepatic stress which provide information to connect the intracellular events (drug metabolism, organelle, cell and whole organ) ultimately leading to tissue damage (apoptosis, necrosis and inflammation). These biomarkers can provide both the means to inform the pharmacologist and chemist with respect to safe drug design, and provide clinicians with valuable tools for patient monitoring.
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Lavergne SN, Wang H, Callan HE, Park BK, Naisbitt DJ. "Danger" conditions increase sulfamethoxazole-protein adduct formation in human antigen-presenting cells. J Pharmacol Exp Ther 2009; 331:372-81. [PMID: 19666748 DOI: 10.1124/jpet.109.155374] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Antigen-presenting cells (APC) are thought to play an important role in the pathogenesis of drug-induced immune reactions. Various pathological factors can activate APC and therefore influence the immune equilibrium. It is interesting that several diseases have been associated with an increased rate of drug allergy. The aim of this project was to evaluate the impact of such "danger signals" on sulfamethoxazole (SMX) metabolism in human APC (peripheral blood mononuclear cells, Epstein-Barr virus-modified B lymphocytes, monocyte-derived dendritic cells, and two cell lines). APC were incubated with SMX (100 microM-2 mM; 5 min-24 h), in the presence of pathological factors: bacterial endotoxins (lipopolysaccharide and staphylococcal enterotoxin B), flu viral proteins, cytokines [interleukin (IL)-1beta, IL-6, IL-10; tumor necrosis factor-alpha; interferon-gamma; and transforming growth factor-beta], inflammatory molecules (prostaglandin E2, human serum complement, and activated protein C), oxidants (buthionine sulfoximine and H(2)O(2)), and hyperthermia (37.5-39.5 degrees C). Adduct formation was evaluated by enzyme-linked immunosorbent assay and confocal microscopy. SMX-protein adduct formation was time- and concentration-dependent for each cell type tested, in both physiological and danger conditions. A danger environment significantly increased the formation of SMX-protein adducts and significantly shortened the delay for their detection. An additive effect was observed with a combination of danger signals. Dimedone (chemical selectively binding cysteine sulfenic acid) and antioxidants decreased both baseline and danger-enhanced SMX-adduct formation. Various enzyme inhibitors were associated with a significant decrease in SMX-adduct levels, with a pattern varying depending on the cell type and the culture conditions. These results illustrate that danger signals enhance the formation of intracellular SMX-protein adducts in human APC. These findings might be relevant to the increased frequency of drug allergy in certain disease states.
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Zhu LY, Peng JC, Reimer PE, Awes TC, Brooks ML, Brown CN, Bush JD, Carey TA, Chang TH, Cooper WE, Gagliardi CA, Garvey GT, Geesaman DF, Hawker EA, He XC, Isenhower LD, Kaplan DM, Kaufman SB, Klinksiek SA, Koetke DD, Lee DM, Lee WM, Leitch MJ, Makins N, McGaughey PL, Moss JM, Mueller BA, Nord PM, Papavassiliou V, Park BK, Petitt G, Sadler ME, Sondheim WE, Stankus PW, Thompson TN, Towell RS, Tribble RE, Vasiliev MA, Webb JC, Willis JL, Wise DK, Young GR. Measurement of angular distributions of Drell-Yan dimuons in p+p interactions at 800 GeV/c. PHYSICAL REVIEW LETTERS 2009; 102:182001. [PMID: 19518860 DOI: 10.1103/physrevlett.102.182001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2008] [Indexed: 05/27/2023]
Abstract
We report a measurement of the angular distributions of Drell-Yan dimuons produced using an 800 GeV/c proton beam on a hydrogen target. The polar and azimuthal angular distribution parameters have been extracted over the kinematic range 4.5<m micromicro<15 GeV/c2 (excluding the Upsilon resonance region), 0<p T <4 GeV/c, and 0<x F<0.8. The p+p angular distributions are similar to those of p+d, and both data sets are compared with models which attribute the cos2varphi distribution either to the presence of the transverse-momentum-dependent Boer-Mulders structure function h1 perpendicular to 1 or to QCD effects. The data indicate the need to include QCD effects before reliable information on the Boer-Mulders function can be extracted. The validity of the Lam-Tung relation in p+p Drell-Yan data is also tested.
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An DJ, Song DS, Park JY, Park BK. A DNA miniarray system for simultaneous visual detection of porcine circovirus type 1 (PCV1) and 2 (PCV2) in pigs. Vet Res Commun 2008; 33:139-47. [PMID: 18651234 PMCID: PMC7088660 DOI: 10.1007/s11259-008-9080-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/03/2008] [Indexed: 11/30/2022]
Abstract
A miniarray system was developed for the simultaneous detection of porcine circovirus type 1 (PCV1) and type 2 (PCV2) in pigs. The system consists of a polymerase chain reaction (PCR) step to amplify target viral DNA, followed by detection of the amplified DNA using a membrane-anchored probe array and an avidin-alkaline phosphatase (Av-AP) indicator system. The lower limit of detection of PCV using the miniarray was 101.9 tissue culture infectious dose 50 (TCID50)/ml and 102.08TCID50/ml for PCV1 and PCV2, respectively, and 100 viral copies/μl for both PCV1 and PCV2. We validated the miniarray system using 141 lymph node specimens from pigs with suspected postweaning multisystemic wasting syndrome or porcine dermatitis and nephropathy syndrome. Of the 141 samples evaluated, 55 were identified as positive for PCV by the miniarray. Relative to in situ hybridization, the sensitivity and specificity of the miniarray was 100% and 98.9%, respectively. In contrast to other microarray systems, the miniarray does not require a DNA chip reader, since the results can be determined by visual inspection of colorized spots on a nylon membrane. This system represents an effective alternative method for the differential detection of PCV1 and PCV2 in pigs, as well as the maintenance of PCV-free cell lines and pre-screening of commercial vaccines for possible contamination.
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Lee CS, Kang BK, Kim HK, Park SJ, Park BK, Jung K, Song DS. Phylogenetic analysis of swine influenza viruses recently isolated in Korea. Virus Genes 2008; 37:168-76. [PMID: 18574682 DOI: 10.1007/s11262-008-0251-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Accepted: 06/09/2008] [Indexed: 11/27/2022]
Abstract
Several influenza A viral subtypes were isolated from pigs during a severe outbreak of respiratory disease in Korea during 2005 and 2006. They included a classical swine H1N1 subtype, two swine-human-avian triple-recombinant H1N2 subtypes, and a swine-human-avian triple-recombinant H3N2 subtype. In the current study, genetic characterization to determine the probable origin of these recent isolates was carried out for the first time. Phylogenetic analysis indicated that all the recent Korean isolates of H1N1, H1N2, and H3N2 influenza are closely related to viruses from the United States. Serologic and genetic analysis indicated that the Korean H1N2 viral subtypes were introduced directly from the United States, and did not arise from recombination between Korean H1N1 and H3N2. We suggest that the H1N1, H1N2, and H3N2 viral subtypes that were isolated from the Korean swine population originated in North America, and that these viruses are currently circulating in the Korean swine population.
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Lee CS, Kang BK, Lee DH, Lyou SH, Park BK, Ann SK, Jung K, Song DS. One-step multiplex RT-PCR for detection and subtyping of swine influenza H1, H3, N1, N2 viruses in clinical samples using a dual priming oligonucleotide (DPO) system. J Virol Methods 2008; 151:30-4. [PMID: 18486976 DOI: 10.1016/j.jviromet.2008.04.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2007] [Revised: 03/25/2008] [Accepted: 04/01/2008] [Indexed: 10/22/2022]
Abstract
The swine influenza virus (SIV) H1N1, H1N2, and H3N2 subtypes circulate in Korean farm. A novel multiplex RT-PCR (m-RT-PCR) was developed to detect and subtype swine influenza viruses. This m-RT-PCR assay could identify H1, H3, N1 and N2 from clinical samples in single tube reaction using DPO system. Korean SIVs are closely related to the United States influenza viruses, and primers were developed for SIV from North American viruses and recently Korean isolates. The sensitivity of the m-RT-PCR was 10TCID(50)/ml for H1N1, H1N2 or H3N2. The lowest viral concentrations detected by single PCR were 1TCID(50)/ml for each subtype. Non-specific reactions were not observed when other viruses and bacteria were used to assess the m-RT-PCR. The results of m-RT-PCR were more effective than virus isolation or hemagglutination (HA) test. This assay using a DPO system provides a rapid, sensitive, and cost-effective laboratory diagnosis for detecting and subtyping of SIV in pigs.
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Zhu LY, Reimer PE, Mueller BA, Awes TC, Brooks ML, Brown CN, Bush JD, Carey TA, Chang TH, Cooper WE, Gagliardi CA, Garvey GT, Geesaman DF, Hawker EA, He XC, Howell DE, Isenhower LD, Kaplan DM, Kaufman SB, Klinksiek SA, Koetke DD, Lee DM, Lee WM, Leitch MJ, Makins N, McGaughey PL, Moss JM, Nord PM, Papavassiliou V, Park BK, Petitt G, Peng JC, Sadler ME, Sondheim WE, Stankus PW, Thompson TN, Towell RS, Tribble RE, Vasiliev MA, Webb JC, Willis JL, Winter P, Wise DK, Yin Y, Young GR. Measurement of Upsilon production for p + p and p + d interactions at 800 GeV/c. PHYSICAL REVIEW LETTERS 2008; 100:062301. [PMID: 18352463 DOI: 10.1103/physrevlett.100.062301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Indexed: 05/26/2023]
Abstract
We report a high statistics measurement of Upsilon production with an 800 GeV/c proton beam on hydrogen and deuterium targets. The dominance of the gluon-gluon fusion process for Upsilon production at this energy implies that the cross section ratio, sigma(p+d-->Upsilon)/2sigma(p+p-->Upsilon), is sensitive to the gluon content in the neutron relative to that in the proton. Over the kinematic region 0<x(F)<0.6, this ratio is found to be consistent with unity, in striking contrast to the behavior of the Drell-Yan cross section ratio sigma(p+d)(DY)/2sigma(p+p)(DY). This result shows that the gluon distributions in the proton and neutron are very similar. The Upsilon production cross sections are also compared with the p+d and p+Cu cross sections from earlier measurements.
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Ford P, Seymour G, Beeley JA, Curro F, Depaola D, Ferguson D, Finkelstein M, Gaengler P, Neo J, Niessen L, Oktay I, Park BK, Wolowski A, Claffey N. Adapting to changes in molecular biosciences and technologies. EUROPEAN JOURNAL OF DENTAL EDUCATION : OFFICIAL JOURNAL OF THE ASSOCIATION FOR DENTAL EDUCATION IN EUROPE 2008; 12 Suppl 1:40-47. [PMID: 18289267 DOI: 10.1111/j.1600-0579.2007.00479.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Dental education, like any other educational programme in a research-intensive university environment, must be research led or at least research informed. In this context, as the research and knowledge base of dentistry lies in the biological and physical sciences, dental education must be led by advances in research in both these areas. There is no doubt that biotechnology and nanotechnology have, over the past 25 years, led research in both these areas. It is therefore logical to assume that this has also impacted on dental education. The aim of this paper is twofold; on one hand to examine the effects of biotechnology and nanotechnology and their implications for dental education and on the other to make recommendations for future developments in dental education led by research in biotechnology and nanotechnology. It is now generally accepted that dental education should be socially and culturally relevant and directed to the community it serves. In other words, there can be no universal approach and each dental school or indeed curriculum must apply the outcomes in their own social, cultural and community settings.
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Park BK, Sushkov AO, Budker D. Precision polarimetry with real-time mitigation of optical-window birefringence. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:013108. [PMID: 18248023 DOI: 10.1063/1.2835902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Optical-window birefringence is frequently a major obstacle in experiments measuring changes in the polarization state of light traversing a sample under investigation. It can contribute a signal indistinguishable from that due to the sample and complicate the analysis. Here, we explore a method to measure and compensate for the birefringence of an optical window using the reflection from the last optical surface before the sample. We demonstrate that this arrangement can cancel out false signals due to the optical-window birefringence-induced ellipticity drift to about 1%, for the values of total ellipticity less than 0.25 rad.
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Jeon YK, Park CH, Kim KY, Li YC, Kim J, Kim YA, Paik JH, Park BK, Kim CW, Kim YN. The heat-shock protein 90 inhibitor, geldanamycin, induces apoptotic cell death in Epstein-Barr virus-positive NK/T-cell lymphoma by Akt down-regulation. J Pathol 2007; 213:170-9. [PMID: 17768706 DOI: 10.1002/path.2219] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
NK/T-cell lymphoma (NKTL) is strongly associated with latent Epstein-Barr virus (EBV) infection. Recently, latent membrane protein 1 (LMP1), an EBV oncoprotein, was reported to activate the phosphatidylinositol-3 kinase (PI3K)/Akt pathway for cell survival. Because geldanamycin (GA) and its derivative, 17-allylamino-17-demethoxygeldanamycin (17-AAG), exhibit anti-tumour activity by degrading HSP90 client proteins, including Akt, we investigated the effect of GA and 17-AAG on the survival of NKTL cell lines. EBV-positive NKTL cell lines, Hank-1 and NK-YS, and an EBV-negative NK leukaemia cell line, NK-L, were treated with PI3K and Akt inhibitors, GA, and 17-AAG, and were subjected to apoptosis and cell viability assays, and immunoblot analysis. EBV-positive B-lymphoblastoid cell lines IM9 and LMP1-transfected IM9 (IM9-LMP1) were also included. Hank-1 and NK-YS cell viability was compromised and apoptosis was induced by LY294002 (PI3K inhibitor) or Akt inhibitor II. GA or 17-AAG administration resulted in the apoptosis of NKTL cells, accompanied by Akt and pAkt down-regulation, caspase 3 activation, and mitochondrial membrane potential disruption. The intrinsic level of pAkt was higher in EBV-positive NKTL cells than in EBV-negative NK-L, and GA or 17-AAG decreased the viability of NKTL cells more efficiently than NK-L. Moreover, IM9-LMP1 was more sensitive to Akt inhibitor II or HSP90 inhibitors than IM9. Importantly, GA showed little effect on the viability of normal peripheral NK cells as non-neoplastic counterparts for comparison. In conclusion, this study suggests that the PI3K/Akt pathway is frequently activated in EBV-positive NKTL and that therapeutic modalities based on targeting the PI3K/Akt pathway with HSP90 inhibitors could be useful for achieving NKTL control.
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MESH Headings
- Antibiotics, Antineoplastic/pharmacology
- Apoptosis/drug effects
- Benzoquinones/pharmacology
- Cell Survival
- Down-Regulation/drug effects
- Drug Evaluation, Preclinical
- HSP90 Heat-Shock Proteins/antagonists & inhibitors
- Herpesvirus 4, Human/isolation & purification
- Humans
- Lactams, Macrocyclic/pharmacology
- Lymphoma, B-Cell/metabolism
- Lymphoma, B-Cell/pathology
- Lymphoma, B-Cell/virology
- Lymphoma, Extranodal NK-T-Cell/metabolism
- Lymphoma, Extranodal NK-T-Cell/pathology
- Membrane Potential, Mitochondrial/physiology
- Oncogene Protein v-akt/metabolism
- Phosphatidylinositol 3-Kinases/metabolism
- Signal Transduction
- Tumor Cells, Cultured
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Zhu LY, Peng JC, Reimer PE, Awes TC, Brooks ML, Brown CN, Bush JD, Carey TA, Chang TH, Cooper WE, Gagliardi CA, Garvey GT, Geesaman DF, Hawker EA, He XC, Isenhower LD, Kaplan DM, Kaufman SB, Klinksiek SA, Koetke DD, Lee DM, Lee WM, Leitch MJ, Makins N, McGaughey PL, Moss JM, Mueller BA, Nord PM, Papavassiliou V, Park BK, Petitt G, Sadler ME, Sondheim WE, Stankus PW, Thompson TN, Towell RS, Tribble RE, Vasiliev MA, Webb JC, Willis JL, Wise DK, Young GR. Measurement of angular distributions of Drell-Yan dimuons in p+d interactions at 800 GeV/c. PHYSICAL REVIEW LETTERS 2007; 99:082301. [PMID: 17930942 DOI: 10.1103/physrevlett.99.082301] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2006] [Indexed: 05/25/2023]
Abstract
We report a measurement of the angular distributions of Drell-Yan dimuons produced using an 800 GeV/c proton beam on a deuterium target. The muon angular distributions in the dilepton rest frame have been measured over the kinematic range 4.5<m{mu mu}<15 GeV/c{2}, 0<p{T}<4 GeV/c, and 0<x{F}<0.8. No significant cos2phi dependence is found in these proton-induced Drell-Yan data, in contrast with the situation for pion-induced Drell-Yan data. The data are compared with expectations from models which attribute the cos2phi distribution to a QCD vacuum effect or to the presence of the transverse-momentum-dependent Boer-Mulders structure function h{1}{perpendicular}. Constraints on the magnitude of the sea-quark h{1}{perpendicular} structure functions are obtained.
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Lee JK, Kim JH, Park BK, Yoo HS, Lee BC, Kim DY. Akabane viral encephalitis in calves in South Korea. Vet Rec 2007; 161:236-8. [PMID: 17704470 DOI: 10.1136/vr.161.7.236] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Kim JH, Hwangbo J, Choi NJ, Park HG, Yoon DH, Park EW, Lee SH, Park BK, Kim YJ. Effect of Dietary Supplementation with Conjugated Linoleic Acid, with Oleic, Linoleic, or Linolenic Acid, on Egg Quality Characteristics and Fat Accumulation in the Egg Yolk. Poult Sci 2007; 86:1180-6. [PMID: 17495090 DOI: 10.1093/ps/86.6.1180] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The effects of conjugated linoleic acid (CLA) with other fatty acids on the fatty acid composition of egg yolk and on egg quality characteristics were studied in 5 groups: 1) CLA 0% (control), 2) CLA 2%, 3) CLA 2%+oleic acid (OA) 2% (CLA+OA), 4) CLA 2%+linoleic acid (LA) 2% (CLA+LA), and 5) CLA 2%+alpha-linolenic acid (LNA) 2% (CLA+LNA). Some parameters of egg quality such as shell thickness, shell strength, yolk color, yolk index, egg diameter, and Haugh units were aggravated when CLA was fed alone, but the quality was improved when CLA was combined with some other fatty acids. The egg production rate, which was decreased by feeding CLA alone, was improved by co-supplementation with LA or OA. An increase in CLA content was observed in all the dietary groups fed CLA for 2 wk. Feeding hens with CLA+LNA led to a linear increase in CLA content in the egg yolk after the fourth week of the feeding trial. Egg yolks from hens given CLA had considerably higher amounts of saturated fatty acids and lower amounts of monounsaturated fatty acids than egg yolks from the control group. The pattern of change in CLA concentration during the feeding trial was similar to the level of C18:0, which was inversely correlated with the level of C18:1. The unsaturated fatty acid co-supplementation strategy applied in this study offers insight into the mechanism of CLA accumulation in the egg yolk without apparent adverse effects on egg quality and egg production.
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Park BK, Kim SH. Transrectal ultrasound performed immediately after prostate biopsy: imaging features and ultrasound-guided compression to bleeding biopsy tract. Acta Radiol 2007; 48:232-7. [PMID: 17354147 DOI: 10.1080/02841850601080457] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE To evaluate the imaging features of transrectal ultrasound (TRUS) performed immediately after prostate biopsy, and to determine whether TRUS-guided compression can stop active bleeding. MATERIAL AND METHODS Systematic 12-core biopsy was performed in 57 consecutive patients, 24 of whom underwent additional target biopsy. The imaging features of grayscale and power Doppler TRUS performed immediately after biopsy were prospectively analyzed, and the complication rate following TRUS-guided bleeding compression was registered. RESULTS Hyperechoic, hypoechoic biopsy needle tracts, or both were seen in 88% (50/57), 72% (41/57), or 61% (35/57), respectively. Power Doppler TRUS performed immediately after biopsy showed 76 bleeding needle tracts in 43 of the 57 (75%) patients, of which 17 were on the right part of the gland and 59 were on the left (P<0.01). TRUS-guided compression times ranged from 1 to 8 min (mean 2.9 min). Hematuria was seen in 38 of 57 patients (67%), with a mean duration of 2.6 days. Hematochezia was seen in 19 of 57 patients (33%), with a mean duration of 0.6 days. Hematuria lasting longer than 3 days occurred in 16 of 57 patients (28%). Hematospermia occurred in 13 of 40 cases (33%). CONCLUSION TRUS performed immediately after biopsy depicted various imaging features and may control postbiopsy bleeding.
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Park BK, Lim JH, Kim MS, Hwang YH, Yun HI. Pharmacokinetics of florfenicol and its major metabolite, florfenicol amine, in rabbits. J Vet Pharmacol Ther 2007; 30:32-6. [PMID: 17217398 DOI: 10.1111/j.1365-2885.2007.00809.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The pharmacokinetics of florfenicol and its active metabolite florfenicol amine were investigated in rabbits after a single intravenous (i.v.) and oral (p.o.) administration of florfenicol at 20 mg/kg bodyweight. The plasma concentrations of florfenicol and florfenicol amine were determined simultaneously by an LC/MS method. After i.v. injection, the terminal half-life (t(1/2lambdaz)), steady-state volume of distribution, total body clearance and mean residence time of florfenicol were 0.90 +/- 0.20 h, 0.94 +/- 0.19 L/kg, 0.63 +/- 0.06 L/h/kg and 1.50 +/- 0.34 h respectively. The peak concentrations (C(max)) of florfenicol (7.96 +/- 2.75 microg/mL) after p.o. administration were observed at 0.90 +/- 0.38 h. The t(1/2lambdaz) and p.o. bioavailability of florfenicol were 1.42 +/- 0.56 h and 76.23 +/- 12.02% respectively. Florfenicol amine was detected in all rabbits after i.v. and p.o. administration. After i.v. and p.o. administration of florfenicol, the observed Cmax values of florfenicol amine (5.06 +/- 1.79 and 3.38 +/- 0.97 microg/mL) were reached at 0.88 +/- 0.78 and 2.10 +/- 1.08 h respectively. Florfenicol amine was eliminated with an elimination half-life of 1.84 +/- 0.17 and 2.35 +/- 0.94 h after i.v. and p.o. administration respectively.
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Song DS, Lee CS, Jung K, Kang BK, Oh JS, Yoon YD, Lee JH, Park BK. Isolation and phylogenetic analysis of H1N1 swine influenza virus isolated in Korea. Virus Res 2006; 125:98-103. [PMID: 17174433 DOI: 10.1016/j.virusres.2006.11.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2006] [Revised: 11/07/2006] [Accepted: 11/17/2006] [Indexed: 11/28/2022]
Abstract
A swine influenza H1N1 virus was isolated from a pig during a severe outbreak of respiratory disease in Korea. All genes of the H1N1 isolate, including hemagglutinin (HA), neuraminidase (NA), matrix (M), nucleoprotein (NP), non-structural (NS), PA, PB1 and PB2, were of swine origin. Also, all these genes showed a close phylogenic relationship with those of H1N1 viruses previously isolated from pigs in the United States. These results suggest that North American swine influenza virus has actually been transmitted to pigs in Korea.
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Kim MS, Lim JH, Park BK, Hwang YH, Yun HI. Pharmacokinetics of enrofloxacin in Korean catfish (Silurus asotus). J Vet Pharmacol Ther 2006; 29:397-402. [PMID: 16958784 DOI: 10.1111/j.1365-2885.2006.00783.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The objective of this study was to evaluate the pharmacokinetic profile of enrofloxacin and its active metabolite, ciprofloxacin, in Korean catfish after intravenous and oral administrations. Enrofloxacin was administered to Korean catfish by a single intravenous and oral administrations at the dose of 10 mg/kg body weight. The plasma concentrations from intravenous and oral administrations of enrofloxacin were determined by LC/MS. Pharmacokinetic parameters from both routes were described to have a two-compartmental model. After intravenous and oral administrations of enrofloxacin, the elimination half-lives (t(1/2,beta)), area under the drug concentration-time curves (AUC), oral bioavailability (F) were 17.44 +/- 4.66 h and 34.13 +/- 11.50 h, 48.1 +/- 15.7 microgxh/mL and 27.3 +/- 12.4 microgxh/mL, and 64.59 +/- 4.58% respectively. The 3.44 +/- 0.81 h maximum concentration (C(max)) of 1.2 +/- 0.2 microg/mL. Ciprofloxacin, an active metabolite of enrofloxacin, was detected at all the determined time-points from 0.25 to 72 h, with the C(max) of 0.17 +/- 0.08 microg/mL for intravenous dose. After oral administration, ciprofloxacin was detected at all the time-points except 0.25 h, with the C(max) of 0.03 +/- 0.01 microg/mL at 6.67 +/- 2.31 h. Ciprofloxacin was eliminated with terminal half-life t(1/2,beta) of 52.08 +/- 17.34 h for intravenous administration and 52.43 +/- 22.37 h for oral administration.
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