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Chung SH, Jiang ES, Lim BS, Kim SH, Chang J. Multi-peak Light-emitting Diode Curing Units and Polymerization of 3D-printed Crown and Bridge Resin. Oper Dent 2024; 49:98-109. [PMID: 38058011 DOI: 10.2341/23-061-l] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/05/2023] [Indexed: 12/08/2023]
Abstract
PURPOSE This study aimed to evaluate the substitutive and additive efficacy of multi-peak light-emitting diode (LED) curing units for post-curing of a three-dimensional- (3D-) printed crown and bridge resin. METHODS A total of 792 disc- and 180 bar-shaped specimens were printed with a crown and bridge resin (NextDent C&B MFH) and post-cured using two LED curing units (VALO Cordless and Bluephase N G4) in fast and standard modes. Conventional post-curing (LC-3D Print Box, Group PC) was compared with LED-only curing (Groups V1, V2, B1, and B2) and LED-combined curing (Groups PV1, PV2, PB1, and PB2) in terms of microhardness, flexural strength, degree of conversion (DC), and CIE L*a*b* color and translucency parameters. Cytotoxicity of the resin eluates was evaluated using the WST-1 assay. Temperature increases on the resin surface were measured with infrared thermography. Data were statistically analyzed using ANOVA and Kruskal-Wallis tests (α=0.05). RESULTS The microhardness and flexural strength in Groups V1, V2, B1, and DC in all LED-only groups were lower than in other groups (p<0.05). Larger color disparities existed between Group PC and all LED-only groups than between Group PC and the others (p<0.05). There was no significant difference in cytotoxicity among the groups. The temperature increase was lowest in Groups V1 and PV1 during light curing (p<0.05). CONCLUSIONS Post-curing by multi-peak LED curing units was not as effective as the conventional post-curing device. Additional post-curing by LED curing units did not improve the material properties.
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Affiliation(s)
- S H Chung
- Shin Hye Chung, DDS, MSD, PhD, Department of Dental Biomaterials Science, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Republic of Korea
| | - E-S Jiang
- En-Shi Jiang, DDS, MSD, PhD, Department of Stomatology, Yanbian University and Affiliated Hospital of Yanbian University, Yanji China
| | - B-S Lim
- Bum-Soon Lim, PhD, Department of Dental Biomaterials Science, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Republic of Korea
| | - S-H Kim
- Seong-Hae Kim, Center for Future Dentistry, Seoul National University, Seoul, Republic of Korea
| | - J Chang
- *Juhea Chang, DDS, MSD, PhD, National Dental Care Center for Persons with Special Needs, Seoul National University Dental Hospital, Seoul, Republic of Korea
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Vasiliev AN, Berdonosov PS, Kozlyakova ES, Maximova OV, Murtazoev AF, Dolgikh VA, Lyssenko KA, Pchelkina ZV, Gorbunov DI, Chung SH, Koo HJ, Whangbo MH. Observation of a 1/3 magnetization plateau in Pb 2Cu 10O 4(SeO 3) 4Cl 7 arising from (Cu 2+) 7 clusters of corner-sharing (Cu 2+) 4 tetrahedra. Dalton Trans 2022; 51:15017-15021. [PMID: 36112086 DOI: 10.1039/d2dt02316d] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A mixed-valence compound Pb2Cu10O4(SeO3)4Cl7 has a complex structure consisting of one nonmagnetic Cu+ (S = 0) ion and four nonequivalent magnetic Cu2+ (S = 1/2) ions. It exhibits antiferromagnetic ordering at TN = 10.2 K. At a temperature below TN, a sequence of spin-flop transition at Bspin-flop = 1.3 T and 1/3 plateau formation at Bspin-flip = 4.4 K is observed in the magnetization curve M(B). The 1/3 magnetization plateau persists at least up to 53.5 T. The spin exchanges of Pb2Cu10O4(SeO3)4Cl7 evaluated by performing energy-mapping analysis based on DFT+U calculations show that the magnetic properties of Pb2Cu10O4(SeO3)4Cl7 are described by the (Cu2+)7 cluster of corner-sharing (Cu2+)4 tetrahedra, and that each (Cu2+)7 cluster has a S = 3/2 spin arrangement in the ground state. The 1/3 magnetization plateau observed for Pb2Cu10O4(SeO3)4Cl7 is explained by the field-induced flip of every second (Cu2+)7 cluster within a unit cell.
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Affiliation(s)
- A N Vasiliev
- Lomonosov Moscow State University, Moscow 119991, Russia. .,National University of Science and Technology "MISiS", Moscow 119049, Russia
| | - P S Berdonosov
- Lomonosov Moscow State University, Moscow 119991, Russia. .,National University of Science and Technology "MISiS", Moscow 119049, Russia
| | - E S Kozlyakova
- Lomonosov Moscow State University, Moscow 119991, Russia. .,National University of Science and Technology "MISiS", Moscow 119049, Russia
| | - O V Maximova
- Lomonosov Moscow State University, Moscow 119991, Russia.
| | - A F Murtazoev
- Lomonosov Moscow State University, Moscow 119991, Russia.
| | - V A Dolgikh
- Lomonosov Moscow State University, Moscow 119991, Russia.
| | - K A Lyssenko
- Lomonosov Moscow State University, Moscow 119991, Russia.
| | - Z V Pchelkina
- Ural Federal University, Ekaterinburg 620002, Russia.,Institute of Metal Physics, RAS, Ekaterinburg 620108, Russia
| | - D I Gorbunov
- Hochfeld-Magnetlabor Dresden (HLD-EMFL), Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - S H Chung
- Kyung Hee University, Seoul 02447, Korea
| | - H-J Koo
- Kyung Hee University, Seoul 02447, Korea
| | - M-H Whangbo
- Kyung Hee University, Seoul 02447, Korea.,North Carolina State University, Raleigh, NC 27695, USA
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Moon W, Chung SH, Chang J. Effect of Deep Margin Elevation on Interfacial Gap Development of CAD/CAM Inlays after Thermomechanical Cycling. Oper Dent 2021; 46:529-536. [PMID: 34757375 DOI: 10.2341/20-310-l] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/20/2021] [Indexed: 11/23/2022]
Abstract
The aim of this study was to evaluate interfacial gap formation of CAD/CAM lithium disilicate inlay margins before and after thermomechanical loading. METHODS AND MATERIALS Mesio-occlusal-distal cavities were prepared on 12 extracted mandibular molars. The gingival margin of one proximal box was elevated with resin modified glass ionomer (RMGI) by a height of 2 mm (Group E [elevation]), and the margin of the other side served as a control (Group NE [no elevation]). Lithium disilicate computer-aided design and computer-aided manufacturing (CAD/CAM) inlays were fabricated and bonded with a self-adhesive resin cement. An aging process was simulated on the specimens under thermomechanical cycling by using a chewing simulator. Marginal integration was evaluated under scanning electron miscroscopy (SEM) using epoxy resin replicas before and after cycling. Marginal areas were stained with silver nitrate solution, and the volumetric gap was measured at the bonded interfaces using microcomputed tomography (CT) before and after cycling. Statistical analyses were performed using paired t-tests, the Wilcoxon signed rank test, and the Mann-Whitney test (a<0.05). RESULTS SEM showed marginal discontinuities in Group NE that increased after thermomechanical cycling. Micro-computed tomography exhibited three-dimensional dye-penetrating patterns at the interfaces before and after cycling. Interfacial disintegration was larger in Group NE before cycling (p<0.05). Thermomechanical cycling increased the gaps in both Groups NE and E (p<0.05). The gap increment from thermomechanical cycling was larger in Group NE (p<0.05). CONCLUSIONS Thermomechanical cycling induced interfacial disintegration at the lithium disilicate CAD/CAM inlays, with deep proximal margins. Margin elevation with RMGI placement reduced the extent of the interfacial gap formation before and after the aging simulation.
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Affiliation(s)
- W Moon
- Wonjoon Moon, DDS, PhD candidate, Department of Dental Biomaterials Science, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Republic of Korea
| | - S H Chung
- Shin Hye Chung, DDS, MSD, PhD, associate professor, Department of Dental Biomaterials Science, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Republic of Korea
| | - J Chang
- *Juhea Chang, DDS, MSD, PhD, clinical professor, National Dental Care Center for Persons with Special Needs, Seoul National University Dental Hospital, Republic of Korea
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Shaban IA, Chan FTS, Chung SH. A novel model to manage air cargo disruptions caused by global catastrophes such as Covid-19. J Air Transp Manag 2021; 95:102086. [PMID: 34548768 PMCID: PMC8445905 DOI: 10.1016/j.jairtraman.2021.102086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 05/27/2021] [Accepted: 05/27/2021] [Indexed: 05/12/2023]
Abstract
The outbreak of the COVID-19 pandemic has drastically disrupted the air cargo industry. This disruption has taken many directions, one of which is the demand imbalance which occurs due to the sudden change in the cargo capacity, as well as demand. Therefore, the random change leads to excessive demand in some routes (hot-selling routes), while some other routes suffer from a big shortage of demand (underutilized routes). Routes are substitutable when there are several adjacent airports in the Origin & Destination (O&D) market. In this market, demand imbalance between substitutable routes occurs because of the above reasons. To tackle the demand imbalance problem, a novel model is introduced to estimate the quantity combinations which maintains the balance between underutilized and hot-selling routes. This model is a variant of the classic Cournot model which captures different quantity scenarios in the form of the best response for each route compared to the other. We then cultivate the model by integrating the Puppet Cournot game with the quantity discount policy. The quantity discount policy is an incentive which motivates the freight forwarders to increase their orders in the underutilized routes. After conducting numerical experiments, the results reveal that the profit can increase up to 25% by using the quantity discount. However, the quantity discount model is only applicable when the profit increase in the hot-selling route is greater than the profit decrease in the underutilized route.
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Affiliation(s)
- Ibrahim Abdelfadeel Shaban
- Mechanical Engineering Department, Faculty of Engineering, Helwan University, Helwan, Cairo, Egypt
- Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hum, Hong Kong
| | - F T S Chan
- Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hum, Hong Kong
| | - S H Chung
- Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hum, Hong Kong
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Harreguy MB, Marfil V, Grooms NWF, Gabel CV, Chung SH, Haspel G. Ytterbium-doped fibre femtosecond laser offers robust operation with deep and precise microsurgery of C. elegans neurons. Sci Rep 2020; 10:4545. [PMID: 32161333 PMCID: PMC7066168 DOI: 10.1038/s41598-020-61479-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 02/25/2020] [Indexed: 11/15/2022] Open
Abstract
Laser microsurgery is a powerful tool for neurobiology, used to ablate cells and sever neurites in-vivo. We compare a relatively new laser source to two well-established designs. Rare-earth-doped mode-locked fibre lasers that produce high power pulses recently gained popularity for industrial uses. Such systems are manufactured to high standards of robustness and low maintenance requirements typical of solid-state lasers. We demonstrate that an Ytterbium-doped fibre femtosecond laser is comparable in precision to a Ti:Sapphire femtosecond laser (1-2 micrometres), but with added operational reliability. Due to the lower pulse energy required to ablate, it is more precise than a solid-state nanosecond laser. Due to reduced scattering of near infrared light, it can lesion deeper (more than 100 micrometres) in tissue. These advantages are not specific to the model system ablated for our demonstration, namely neurites in the nematode C. elegans, but are applicable to other systems and transparent tissue where a precise micron-resolution dissection is required.
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Affiliation(s)
- M B Harreguy
- New Jersey Institute of Technology and Rutgers University, Federated Department of Biological Sciences and New Jersey Institute of Technology, Institute of Brain Research and Neuroscience, 100 Summit St, Newark, NJ, 07102, USA
| | - V Marfil
- New Jersey Institute of Technology and Rutgers University, Federated Department of Biological Sciences and New Jersey Institute of Technology, Institute of Brain Research and Neuroscience, 100 Summit St, Newark, NJ, 07102, USA
| | - N W F Grooms
- Northeastern University, Department of Bioengineering, 360 Huntington Avenue, Boston, MA, 02115, USA
| | - C V Gabel
- Department of Physiology and Biophysics and Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine and Boston University Photonics Center, 700 Albany St, Boston, Massachusetts, 02215, USA
| | - S H Chung
- Northeastern University, Department of Bioengineering, 360 Huntington Avenue, Boston, MA, 02115, USA.
| | - G Haspel
- New Jersey Institute of Technology and Rutgers University, Federated Department of Biological Sciences and New Jersey Institute of Technology, Institute of Brain Research and Neuroscience, 100 Summit St, Newark, NJ, 07102, USA.
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Lin TL, Chung SH, Sung CH, Yeh SY, Cheng TL, Chou CC. Establishment of feline in-house reference intervals for hematologic and biochemical parameters and potential age-related differences. Pol J Vet Sci 2020; 22:599-608. [PMID: 31560478 DOI: 10.24425/pjvs.2019.129969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Reference intervals (RIs) are one of the essential elements in the procedure of disease diagnosis. This is especially true for feline species in which RI is less available than in canine species. RIs are affected by biological, geographical and instrumental factors, yet published RIs with incomplete background are popularly used. Inappropriate interpretations of RIs may affect classification of disease and subsequent treatment. In this study, we demonstrated the step-by-step establishment of feline RIs following the American Society for Veterinary Clinical Pathology (ASVCP) reference interval guideline. A total of 51 parameters were examined, including 20 hematology and 31 biochemistry parameters, and the results were compared to one local RI and two foreign RIs. Overall, about 29% (10/35) of tested parameters were different form local RIs and 60% (30/50) were different from the two foreign RIs, highlighting geographical variations. A higher upper reference limit (URL) in red blood cell count (RBC), hematocrit (Hct), Hemoglobin (Hgb), albumin, creatinine and lower URL in potassium and white blood cell count (WBC) were identified, which may impact the interpretation. In addition, statistical analysis of age and gender were factored separately and indicated that 10 parameters were significantly higher in the adult group. For the impact of gender, percentage of basophil and total iron-binding capacity (TIBC) were lower in female and male cats, respectively. In conclusion, we have demonstrated that it is desirable to establish in-house RIs or RIs of local sources. An age specific RI for the geriatric feline population is advisable for better diagnosis and monitoring the disease.
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Affiliation(s)
- T L Lin
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung-Hsing University, 250-1 Kuo-Kuang Rd., Taichung 40254, Taiwan
| | - S H Chung
- Tai-Da Animal Hospital, No. 11, Section 2, Wenhua Road, Banqiao District, New Taipei City, 220
| | - C H Sung
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung-Hsing University, 250-1 Kuo-Kuang Rd., Taichung 40254, Taiwan
| | - S Y Yeh
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung-Hsing University, 250-1 Kuo-Kuang Rd., Taichung 40254, Taiwan
| | - T L Cheng
- Veterinary Medical Teaching Hospital, College of Veterinary Medicine, National Chung-Hsing University, 250-1 Kuo-Kuang Rd., Taichung 40254, Taiwan
| | - C C Chou
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung-Hsing University, 250-1 Kuo-Kuang Rd., Taichung 40254, Taiwan
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7
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Mun ST, Chung SH. 1478 Retrospective Comparisson In Single Port Total Laparoscopic Hysterectomy Between Conventional Intracorporeal Barbed Suture and Vaginal Approach Barbed Suture. J Minim Invasive Gynecol 2019. [DOI: 10.1016/j.jmig.2019.09.131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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8
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Baclig NV, Ngo C, Yeh AC, Chung SH, Cheng A, Grim J, Graf SA, Yang KC. Steroid-Refractory Autoimmune Myocarditis after Pembrolizumab Therapy: Failure of Equine Anti-Thymocyte Globulin to Prevent Heart Failure. J Clin Case Rep 2019; 2:1-4. [PMID: 36712142 PMCID: PMC9881190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
While immune checkpoint inhibitors (ICIs) are improving outcomes for many cancers, they can have severe adverse effects. Though cardiac immune-related adverse effects (irAEs) are rare, they have considerable morbidity and mortality. Prior case studies have demonstrated successful treatment of ICI induced autoimmune myocarditis with a variety of immunosuppressive regimens. This case describes steroid-refractory autoimmune myocarditis after treatment with pembrolizumab. Treatment with equine anti-thymocyte globulin, a regimen previously documented to reverse ICI induced autoimmune myocarditis, temporarily improved clinical status and cardiac biomarkers, however eventually failed to prevent progression to heart failure and cardiovascular death. This case highlights the importance of early stress-dose steroids, identifies troponin as a potential marker of treatment response, and underscores the value of collaboration between oncology and cardiology for optimal management.
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Affiliation(s)
- NV Baclig
- Department of Medicine, University of Washington, USA,Correspondence: Baclig NV, Department of Medicine, University of Washington, 325 Ninth Ave, Seattle, WA, 98104-2420; USA. Tel: (847)-609-2487, Fax: (206) 744-1554l,
| | - C Ngo
- Division of Cardiology, Department of Medicine, University of Washington, USA
| | - AC Yeh
- Division of Hematology, Division of Medical Oncology, Department of Medicine, University of Washington, USA
| | - SH Chung
- Department of Pharmacology, Veterans Affairs Puget Sound Health Care System, USA
| | - A Cheng
- Division of Cardiology, Department of Medicine, University of Washington, USA
| | - J Grim
- Division of Medical Oncology, Department of Medicine, University of Washington, USA
| | - SA Graf
- Division of Medical Oncology, Department of Medicine, University of Washington, USA
| | - KC Yang
- Division of Cardiology, Department of Medicine, University of Washington, USA
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Chen W, Shimane T, Kawano S, Alshaikh A, Kim SY, Chung SH, Kim RH, Shin KH, Walentin K, Park NH, Schmidt-Ott KM, Kang MK. Human Papillomavirus 16 E6 Induces FoxM1B in Oral Keratinocytes through GRHL2. J Dent Res 2018; 97:795-802. [PMID: 29443638 DOI: 10.1177/0022034518756071] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
High-risk human papillomavirus (HPV) is a major risk factor for oral and pharyngeal cancers (OPCs), yet the detailed mechanisms by which HPV promotes OPCs are not understood. Forkhead box M1B (FoxM1B) is an oncogene essential for cell cycle progression and tumorigenesis, and it is aberrantly overexpressed in many tumors. We previously showed that FoxM1B was the putative target of an epithelial-specific transcription factor, Grainyhead-like 2 (GRHL2). In the current study, we demonstrate that HPV type 16 (HPV-16) E6 induces FoxM1B in human oral keratinocytes (HOKs) and tonsillar epithelial cells (TECs) in part through GRHL2. FoxM1B was barely detectable in cultured normal human oral keratinocytes (NHOKs) and progressively increased in immortalized HOKs harboring HPV-16 genome (HOK-16B) and tumorigenic HOK-16B/BaP-T cells. Retroviral expression of HPV-16 E6 and/or E7 in NHOKs, TECs, and hypopharyngeal carcinoma cells (FaDu) revealed induction of FoxM1B and GRHL2 by the E6 protein but not E7. Both GRHL2 and FoxM1B were strongly induced in the epidermis of HPV-16 E6 transgenic mice and HPV+ oral squamous cell carcinomas. Ectopic expression of FoxM1B led to acquisition of transformed phenotype in HOK-16B cells. Loss of FoxM1B by lentiviral short hairpin RNA vector or chemical inhibitor led to elimination of tumorigenic characteristics of HOK-16B/BaP-T cells. Luciferase reporter assay revealed that GRHL2 directly bound and regulated the FoxM1B gene promoter activity. Using epithelial-specific Grhl2 conditional knockout mice, we exposed wild-type (WT) and Grhl2 KO mice to 4-nitroquinolin 1-oxide (4-NQO), which led to induction of FoxM1B in the tongue tissues and rampant oral tumor development in the WT mice. However, 4-NQO exposure failed to induce tongue tumors or induction of FoxM1B expression in Grhl2 KO mice. Collectively, these results indicate that HPV-16 induces FoxM1B in part through GRHL2 transcriptional activity and that elevated FoxM1B level is required for oropharyngeal cancer development.
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Affiliation(s)
- W Chen
- 1 The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, CA, USA
| | - T Shimane
- 2 Department of Dentistry and Oral Surgery, Shinshu University School of Medicine, Matsumoto, Nagano, Japan
| | - S Kawano
- 3 Asahi University School of Dentistry, Gifu, Japan
| | - A Alshaikh
- 1 The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, CA, USA
| | - S Y Kim
- 1 The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, CA, USA
| | - S H Chung
- 4 Deptartment of Biology and Biochemistry, University of Houston, Houston, TX, USA
| | - R H Kim
- 1 The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, CA, USA.,5 UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA, USA
| | - K H Shin
- 1 The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, CA, USA.,5 UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA, USA
| | - K Walentin
- 6 Max Delbruck Center for Molecular Medicine and Department of Nephrology, Charité Medical University, Berlin, Germany
| | - N H Park
- 1 The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, CA, USA.,5 UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA, USA
| | - K M Schmidt-Ott
- 6 Max Delbruck Center for Molecular Medicine and Department of Nephrology, Charité Medical University, Berlin, Germany
| | - M K Kang
- 1 The Shapiro Family Laboratory of Viral Oncology and Aging Research, UCLA School of Dentistry, Los Angeles, CA, USA.,5 UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA, USA
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Shin JS, Chung SH, Lee WS, Lee JY, Kim JL, Lee KT. Immunostimulatory effects of cordycepin-enriched WIB-801CE from Cordyceps militaris
in splenocytes and cyclophosphamide-induced immunosuppressed mice. Phytother Res 2017; 32:132-139. [DOI: 10.1002/ptr.5960] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 08/21/2017] [Accepted: 10/02/2017] [Indexed: 12/27/2022]
Affiliation(s)
- Ji-Sun Shin
- Department of Pharmaceutical Biochemistry; College of Pharmacy, Kyung Hee University; 26, Kyungheedae-ro, Dongdaemun-gu Seoul 02447 Korea
| | - Soo-Hak Chung
- Central Research Institute, Whanin Pharm. Co., Ltd GBSA; 107, Gwanggyo-ro Yeongtong-gu, Suwon, Gyeonggi-do 16229 Korea
| | - Woo-Seok Lee
- Department of Pharmaceutical Biochemistry; College of Pharmacy, Kyung Hee University; 26, Kyungheedae-ro, Dongdaemun-gu Seoul 02447 Korea
- Department of Life and Nanopharmaceutical Science; College of Pharmacy, Kyung Hee University; 26, Kyungheedae-ro, Dongdaemun-gu Seoul 02447 Korea
| | - Je-Young Lee
- Central Research Institute, Whanin Pharm. Co., Ltd GBSA; 107, Gwanggyo-ro Yeongtong-gu, Suwon, Gyeonggi-do 16229 Korea
| | - Jong-Lae Kim
- Central Research Institute, Whanin Pharm. Co., Ltd GBSA; 107, Gwanggyo-ro Yeongtong-gu, Suwon, Gyeonggi-do 16229 Korea
| | - Kyung-Tae Lee
- Department of Pharmaceutical Biochemistry; College of Pharmacy, Kyung Hee University; 26, Kyungheedae-ro, Dongdaemun-gu Seoul 02447 Korea
- Department of Life and Nanopharmaceutical Science; College of Pharmacy, Kyung Hee University; 26, Kyungheedae-ro, Dongdaemun-gu Seoul 02447 Korea
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Cochran JM, Chung SH, Leproux A, Baker WB, Busch DR, DeMichele AM, Tchou J, Tromberg BJ, Yodh AG. Longitudinal optical monitoring of blood flow in breast tumors during neoadjuvant chemotherapy. Phys Med Biol 2017; 62:4637-4653. [PMID: 28402286 DOI: 10.1088/1361-6560/aa6cef] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We measure tissue blood flow markers in breast tumors during neoadjuvant chemotherapy and investigate their correlation to pathologic complete response in a pilot longitudinal patient study (n = 4). Tumor blood flow is quantified optically by diffuse correlation spectroscopy (DCS), and tissue optical properties, blood oxygen saturation, and total hemoglobin concentration are derived from concurrent diffuse optical spectroscopic imaging (DOSI). The study represents the first longitudinal DCS measurement of neoadjuvant chemotherapy in humans over the entire course of treatment; it therefore offers a first correlation between DCS flow indices and pathologic complete response. The use of absolute optical properties measured by DOSI facilitates significant improvement of DCS blood flow calculation, which typically assumes optical properties based on literature values. Additionally, the combination of the DCS blood flow index and the tissue oxygen saturation from DOSI permits investigation of tissue oxygen metabolism. Pilot results from four patients suggest that lower blood flow in the lesion-bearing breast is correlated with pathologic complete response. Both absolute lesion blood flow and lesion flow relative to the contralateral breast exhibit potential for characterization of pathological response. This initial demonstration of the combined optical approach for chemotherapy monitoring provides incentive for more comprehensive studies in the future and can help power those investigations.
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Affiliation(s)
- J M Cochran
- Department of Physics and Astronomy, University of Pennsylvania, 209 S 33rd St, Philadelphia, PA 19104, United States of America
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Ban HY, Schweiger M, Kavuri VC, Cochran JM, Xie L, Busch DR, Katrašnik J, Pathak S, Chung SH, Lee K, Choe R, Czerniecki BJ, Arridge SR, Yodh AG. Heterodyne frequency-domain multispectral diffuse optical tomography of breast cancer in the parallel-plane transmission geometry. Med Phys 2017; 43:4383. [PMID: 27370153 DOI: 10.1118/1.4953830] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
PURPOSE The authors introduce a state-of-the-art all-optical clinical diffuse optical tomography (DOT) imaging instrument which collects spatially dense, multispectral, frequency-domain breast data in the parallel-plate geometry. METHODS The instrument utilizes a CCD-based heterodyne detection scheme that permits massively parallel detection of diffuse photon density wave amplitude and phase for a large number of source-detector pairs (10(6)). The stand-alone clinical DOT instrument thus offers high spatial resolution with reduced crosstalk between absorption and scattering. Other novel features include a fringe profilometry system for breast boundary segmentation, real-time data normalization, and a patient bed design which permits both axial and sagittal breast measurements. RESULTS The authors validated the instrument using tissue simulating phantoms with two different chromophore-containing targets and one scattering target. The authors also demonstrated the instrument in a case study breast cancer patient; the reconstructed 3D image of endogenous chromophores and scattering gave tumor localization in agreement with MRI. CONCLUSIONS Imaging with a novel parallel-plate DOT breast imager that employs highly parallel, high-resolution CCD detection in the frequency-domain was demonstrated.
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Affiliation(s)
- H Y Ban
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - M Schweiger
- Department of Computer Science, University College London, London WC1E 7JE, United Kingdom
| | - V C Kavuri
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - J M Cochran
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - L Xie
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - D R Busch
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - J Katrašnik
- Faculty of Electrical Engineering, University of Ljubljana, Ljubljana 1000, Slovenia
| | - S Pathak
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - S H Chung
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - K Lee
- Daegu Gyeongbuk Institute of Science and Technology, Daegu 711-813, South Korea
| | - R Choe
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14642
| | - B J Czerniecki
- Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - S R Arridge
- Department of Computer Science, University College London, London WC1E 7JE, United Kingdom
| | - A G Yodh
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104
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Lee CKM, Yeung CL, Xiong ZR, Chung SH. A mathematical model for municipal solid waste management - A case study in Hong Kong. Waste Manag 2016; 58:430-441. [PMID: 27353392 DOI: 10.1016/j.wasman.2016.06.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Revised: 05/20/2016] [Accepted: 06/11/2016] [Indexed: 06/06/2023]
Abstract
With the booming economy and increasing population, the accumulation of waste has become an increasingly arduous issue and has aroused the attention from all sectors of society. Hong Kong which has a relative high daily per capita domestic waste generation rate in Asia has not yet established a comprehensive waste management system. This paper conducts a review of waste management approaches and models. Researchers highlight that mathematical models provide useful information for decision-makers to select appropriate choices and save cost. It is suggested to consider municipal solid waste management in a holistic view and improve the utilization of waste management infrastructures. A mathematical model which adopts integer linear programming and mixed integer programming has been developed for Hong Kong municipal solid waste management. A sensitivity analysis was carried out to simulate different scenarios which provide decision-makers important information for establishing Hong Kong waste management system.
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Affiliation(s)
- C K M Lee
- Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
| | - C L Yeung
- Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Z R Xiong
- Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - S H Chung
- Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
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14
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Chmilewsky F, About I, Chung SH. C5L2 Receptor Represses Brain-Derived Neurotrophic Factor Secretion in Lipoteichoic Acid-Stimulated Pulp Fibroblasts. J Dent Res 2016; 96:92-99. [PMID: 28033061 DOI: 10.1177/0022034516673832] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The anaphylatoxin C5a constitutes a powerful fragment generated by complement system activation. Interestingly, this complement active fragment is also an important mediator of tissue regeneration. Recent findings suggest that C5a could be an initial signal orchestrating pulp nerve sprouting beneath carious injury, a critical step in dentin-pulp regeneration. Indeed, the expression and activation of the C5a active receptor (C5aR/CD88) by injured pulp fibroblasts controls the direction of neurite outgrowth toward carious injuries by modulating the secretion of brain-derived neurotrophic factor (BDNF) by pulp fibroblasts. A second C5a receptor, C5L2, has also been cloned but has received much less attention because its interaction with the ligand induces no signaling. This work aims to investigate the role of C5L2 in pulp nerve regeneration in the secretion of BDNF by pulp fibroblasts under sites of carious injury. Using fluorescence immunostaining on human tooth sections in vivo and on primary human pulp fibroblasts in vitro, the authors reveal that C5L2 and C5aR are co-expressed by pulp fibroblasts under lipoteichoic acid (LTA) stimulation. Moreover, silencing C5L2 significantly increases BDNF secretion by LTA-stimulated pulp fibroblasts. Finally, an analysis of the subcellular distribution of C5aR and C5L2 indicates that the negative regulation of BDNF secretion by C5L2 correlates with C5aR activation and its subsequent intracellular co-localization with C5L2. Overall, the current study sheds light on the mechanism of pulp nerve regeneration by identifying C5L2 as a negative regulator of BDNF secretion by pulp fibroblasts under carious teeth. This knowledge significantly increases the understanding of the functional mechanism linking C5aR and C5L2 in pulp nerve regeneration, which may be useful in future dentin-pulp engineering strategies that target fibroblast C5L2 to induce pulp innervation.
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Affiliation(s)
- F Chmilewsky
- 1 Department of Oral Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - I About
- 2 Aix Marseille University, CNRS, ISM, Institute Movement Science, Marseille, France
| | - S H Chung
- 1 Department of Oral Biology, University of Illinois at Chicago, Chicago, IL, USA
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15
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Chung SH, Feldman MD, Martinez D, Kim H, Busch DR, Yodh AG. Abstract P2-03-10: Non-invasively measured Warburg effect: Optically measured tissue oxygenation and its correlation with Ki67 proliferation. Cancer Res 2013. [DOI: 10.1158/0008-5472.sabcs13-p2-03-10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Clinically, the level of Ki67 expression is used as a biomarker for cancer proliferation. In this clinical study, we focus on malignant tumor properties and investigate the correlations between macroscopically measured Diffuse Optical Tomography (DOT) physiological parameters with the Ki67 proliferation marker. The DOT tumor-to-normal tissue parameters were previously shown to have excellent tumor sensitivity and specificity by Choe and co-workers (JBO, 14(2):024020).
In order to quantify cell proliferation, the percent of Ki67-expressing nuclei (i.e., from all the nuclei in an ROI) was used to specify Ki67 expression in cancer and normal tissues. Then, the tumor-to-normal ratio of Ki67-expressing nuclei was calculated to derive “relative” Ki67 values (i.e., rKi67). For this analysis, only normal glandular tissues with Ki67 expression were used. For these determinations of rKi67, the range of the Ki67-nuclei present in cancer tissues was 0.36-23.45% (N = 8), and in normal tissues it was 0.19-7.41% (N = 8). Ki67-expression in cancer-only tissues was also compared to DOT parameters. The range of the Ki67 present in cancer used for the analysis of the cancer-only tissues was 0.36-27.77% (N = 15). Among the DOT parameters, rStO2 (relative tissue oxygenation) and rHbO2 (relative oxy-hemoglobin concentration) were highly correlated with rKi67 as shown in table 1 (Pearson correlation: 0.92, p-value: 0.001 for rStO2 and correlation: 0.93, p-value: 0.002 for rHbO2). Also, for cancer-only Ki67, rHb (relative deoxy-hemoglobin concentration) showed a weak inverse correlation with cancer Ki67%: correlation: -0.58, p-value: 0.026. We additionally tested if the Diffuse Optical Tomography parameters are significantly different in more proliferative cancer compared to the less proliferative cancer (as determined by the 15% cutoff point). For this purpose, only rHb differentiated Ki67-positive from Ki67-negative cancer, with lower values of rHb occurring for the Ki67-positive cancer (p-value: 0.018, Wilcoxon-ranked-sum test).
In this correlation study, we observed that rKi67 was highly correlated with rStO2 and rHbO2. Further, the cancer-only Ki67 showed lower correlations with the relative DOT parameters. However, we found that rHb was inversely correlated with cancer-only Ki67 percent values. Additionally, rHb was lower in the Ki67-positive cancer compared to the Ki67-negative cancer (using the 15% cutoff point). Taken together, these results suggest that in more proliferative cancers, although more oxy-hemoglobin might be supplied to the cancer, the level of oxygenated-hemoglobin remains high and less oxygen is utilized for cancer metabolism (i.e., consistent with lower rHb). This finding appears to be consistent with the Warburg effect, which accounts for the fact that proliferative cells will go through glycolysis to increase biomass without using oxygen, despite sufficient presence of oxygen in the tissue environment. Overall, the results of this study corroborate expectations that macroscopic measurement of breast cancer physiology using DOT can reveal information microscopic pathological properties of breast cancer.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-03-10.
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Affiliation(s)
- SH Chung
- University of Pennsylvania; Hospital of the University of Pennsylvania; The Children's Hospital of Philadelphia; University of Rochester
| | - MD Feldman
- University of Pennsylvania; Hospital of the University of Pennsylvania; The Children's Hospital of Philadelphia; University of Rochester
| | - D Martinez
- University of Pennsylvania; Hospital of the University of Pennsylvania; The Children's Hospital of Philadelphia; University of Rochester
| | - H Kim
- University of Pennsylvania; Hospital of the University of Pennsylvania; The Children's Hospital of Philadelphia; University of Rochester
| | - DR Busch
- University of Pennsylvania; Hospital of the University of Pennsylvania; The Children's Hospital of Philadelphia; University of Rochester
| | - AG Yodh
- University of Pennsylvania; Hospital of the University of Pennsylvania; The Children's Hospital of Philadelphia; University of Rochester
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16
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Kim TH, Jo S, Park Y, Lee HH, Chung SH, Lee WS. Differences in omega-3 and fatty acid profiles between patients with endometriosis and those with a functional ovarian cyst. J OBSTET GYNAECOL 2013; 33:597-600. [PMID: 23919858 DOI: 10.3109/01443615.2013.786029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Endometriosis is a chronic inflammatory gynaecological disease. Problems associated with endometriosis include dysmenorrhoea, dyspareunia and infertility. We evaluated the omega-3 and fatty acid profiles in erythrocytes and tissues in patients with endometriosis (n = 10) or a functional ovarian cyst (n = 12), using a food frequency questionnaire that included questions about 117 food items typical of Korean meals. Erythrocyte levels of 20:5n3 and 22:6n3, the omega-3 index, and n-3 PUFA were significantly higher, and the n-6:n-3 ratio was significantly lower in the endometriosis group than in the functional ovarian cyst group. The functional ovarian cyst group consumed significantly more fruit than the group with endometriosis.
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Affiliation(s)
- T H Kim
- Department of Obstetrics and Gynecology, College of Medicine, Soonchunhyang University, Bucheon
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17
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Bae K, Na JB, Choi DS, Cho JM, Choi HC, Jeon KN, Park MJ, Choi HY, Kim JE, Chung SH. Contrast-enhanced MR cholangiography: comparison of Gd-EOB-DTPA and Mn-DPDP in healthy volunteers. Br J Radiol 2012; 85:1250-4. [PMID: 22553292 DOI: 10.1259/bjr/22238911] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE The purpose of this study was to compare the biliary enhancement dynamics of gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic-acid (Gd-EOB-DTPA) and mangafodipir trisodium (Mn-DPDP) for contrast-enhanced MR cholangiography (MRC) in healthy subjects. METHODS 15 healthy volunteers underwent MRI at 1.5 T with volumetric interpolated breath-hold examination sequence. Each volunteer was scanned once for each contrast agent. The signal-to-noise ratio (SNR) of the liver parenchyma and common hepatic duct (CHD) and the contrast-to-noise ratio (CNR) of CHD to liver parenchyma were evaluated and compared before and at several time points (5, 15, 30, 45, 60, 90, and 120 min) after injection of each agent. RESULTS SNR was significantly higher for Gd-EOB-DTPA than for Mn-DPDP in liver parenchyma after 5 min and in CHD after 15 min (p<0.05). CNR of CHD to liver parenchyma using Gd-EOB-DTPA showed an initial decrease at 5 min post-injection followed by a steep increase to a peak at 15 min post-injection. CNR using Mn-DPDP showed a steady increase to a peak at 15 min post-injection without an initial decrease. At 15 min, the value of CNR was significantly higher for Gd-EOB-DTPA than for Mn-DPDP (p<0.05). CONCLUSION For both contrast agents, CNR reached a peak at 15 min after contrast injection. At this time point, CNR of Gd-EOB-DTPA was significantly higher than that of Mn-DPDP. Therefore, Gd-EOB-DTPA may provide better contrast-enhanced MRC than Mn-DPDP at 15 min after contrast administration.
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Affiliation(s)
- K Bae
- Department of Radiology, Gyeongsang National University Hospital, Gyeongsang National University School of Medicine, Jinju, Republic of Korea
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18
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Kim TH, Lee HH, Kim JM, Chung SH. Hysterectomy prevention using the uterine hollow obliterations (HYUNHO) method for placenta previa. CLIN EXP OBSTET GYN 2012; 39:462-465. [PMID: 23444744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
OBJECTIVE We have invented a method of hysterectomy prevention called the uterine hollow obliteration (HYUNHO) method to preserve the uterus and fertility after treating placenta previa or accreta. METHODS Eighty patients underwent cesarean section because of placenta previa between January 2003 and December 2009. All patients eligible for the study were evaluated by followup and a telephone questionnaire about fertility, menstruation recovery, and complications. RESULTS The success rate on preserving the uterus with the HYUNHO method was 96.2%. Three cases required additional procedures, including a cesarean hysterectomy or uterine artery embolization (UAE), two cases underwent a cesarean hysterectomy after delivery, and one case underwent UAE. CONCLUSION The HYUNHO method is a safe, easy method for placenta previa, although it should be evaluated in a randomized controlled trial.
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Affiliation(s)
- T H Kim
- Department of Obstetrics and Gynecology, Soonchunhyang University Bucheon Hospital, Bucheon, Republic of Korea
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19
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Lee WS, Park ES, Kim DH, Kim TH, Lee HH, Chung SH. Expression of p53, p27 and Jab1 protein in epithelial ovarian tumors. EUR J GYNAECOL ONCOL 2012; 33:358-362. [PMID: 23091890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
OBJECTIVE The study aimed to investigate expression of p53, p27 and Jun activation domain-binding protein 1 (Jab1) proteins in epithelial ovarian tumors and the values of these factors as discriminating markers for the transformation of borderline tumors to cancers. METHODS Forty-seven cases of paraffin-embedded tissues of epithelial ovarian tumors including 22 cases of benign ovarian tumors, nine cases of borderline tumors, and 16 cases of invasive cancers were used to evaluate expression of p53, p27 and Jab1 proteins by immunohistochemical methods. RESULTS p53 protein was expressed in 13.6% of the benign tumors, 44.4% of the borderline tumors and 62.5% of the malignant tumors and p27 protein was expressed in 95.5% of the benign tumors, 66.7% of the borderline tumors, and 37.5% of the malignant tumors. Expression of Jab1 protein was observed in 22.7% of the benign tumors, 77.8% of the borderline tumors and 62.5% of the malignant tumors. Expressions of p53, p27 and Jab1 proteins in malignant tumors were all higher than in benign tumors and the expression of p27 protein in malignant tumors was lower than in benign tumors (p < 0.05). Expression of Jab1 protein in borderline tumors was significantly higher than in benign tumors (p < 0.05). CONCLUSIONS Expression of p53, p27 and Jab1 proteins can be used to discriminate between benign and malignant tumors in epithelial ovarian tumors.
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Affiliation(s)
- W S Lee
- Department of Obstetrics and Gynecology, College of Medicine, Soonchunhyang University, Bucheon, Republic of Korea.
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20
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Chung SH, Feldman M, Choe R, Martinez D, Yodh AG. P2-10-03: Non-Invasive In Vivo Characterization of Cancer-Cell Proliferation & Angiogenesis in Cancer-Cell-Surrounding Stromal Microenvironment In-Vivo Using Diffuse Optical Tomography. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-p2-10-03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Cancer cell proliferation and stromal microenvironment changes have been shown to indicate tumor growth (Orimo, Weinberg et al., Cell, 2005, Coussens and Werb, Nature, 2002). However, most studies were performed using excised tissue samples or cultured cells. In-vivo characterization of these properties in human breast cancer could magnify the importance of recent findings from in-vitro tissues. Diffuse Optical Tomography (DOT) provides quantitative three-dimensional (3D) images of the physiological and pathological properties of breast cancer tissues in vivo. In this study, we investigate the relationship between DOT measured physiological parameters, such as hemoglobin & tissue oxygenation that differentiate malignant, benign and normal breast tissues (Choe, Yodh et al. JBO, 2009), and histologically quantified Ki67 expression in cancer cell nuclei and vasculature in the stromal microenvironment surrounding breast cancer cells.
Methods: DOT was employed to measure 20 infiltrating ductal carcinoma patients. DOT utilizes non-ionizing low power near infrared light to examine a subject laying in the prone position on a bed with her breasts inside a breast box. DOT quantifies oxy- and deoxy-hemoglobin concentration and tissue oxygenation. Cancer proliferation was quantified by calculating Ki67 stained nuclei percent and vascular area (calculated by detecting CD34 stained vascular structure using automated RGB based software).
Results: The ratio of Ki67 expression in cancer cells to surrounding normal cells was correlated with DOT-measured tumor-to-normal ratio of volume-averaged oxy-hemoglobin and tissue oxygen saturation (R=0.72, p-value: 0.0197 and R=0.68, p-value: 0.0293, respectively, N=10). The vascular area (μm2) the surrounding stroma was correlated with total hemoglobin concentration and oxy-hemoglobin (R=0.49, p-value: 0.1238 and R=0.43, p-value: 0.1819, respectively, N=11). Additionally, cancer-to-normal ratio of nuclei compactness and cancer micro-vessel density was correlated with tumor-to-normal ratio of oxy-hemoglobin concentration (R=0.43, p-value: 0.056 and R=0.43, p-value:0.058, respectively, N=20).
Discussion: The positive correlations between Ki67 cancer-proliferation-marker and tissue oxy-hemoglobin concentration indicate that DOT detects increased oxygenated environment for proliferating cells. The observation that nuclei compactness increases with oxy-hemoglobin concentration also supports the statement above, and, the correlation between hemoglobin concentration and vascular area in surrounding stroma suggests that DOT measures tumor growth stimulated by stromal micro-environment changes. The difference between the field of view needed to calculate a parameter value (i.e., macroscopic (cm3) for DOT and microscopic (|im3) for histology) likely lowers the correlation between the two technologies. However, the results of this study clearly suggest that DOT measures tumor growth due to proliferation of cancer cells and angiogenesis in cancer-cell-surrounding stroma. This work was supported by NIH and the Susan G. Komen for the Cure foundation.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-10-03.
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Affiliation(s)
- SH Chung
- 1University of Pennsylvania; Hospital of the University of Pennsylvania; The Children's Hospital of Philadelphia; University of Rochester
| | - M Feldman
- 1University of Pennsylvania; Hospital of the University of Pennsylvania; The Children's Hospital of Philadelphia; University of Rochester
| | - R Choe
- 1University of Pennsylvania; Hospital of the University of Pennsylvania; The Children's Hospital of Philadelphia; University of Rochester
| | - D Martinez
- 1University of Pennsylvania; Hospital of the University of Pennsylvania; The Children's Hospital of Philadelphia; University of Rochester
| | - AG Yodh
- 1University of Pennsylvania; Hospital of the University of Pennsylvania; The Children's Hospital of Philadelphia; University of Rochester
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Jung SY, Song HS, Park SY, Chung SH, Kim YJ. Pyruvate promotes tumor angiogenesis through HIF-1-dependent PAI-1 expression. Int J Oncol 2010; 38:571-6. [PMID: 21132271 DOI: 10.3892/ijo.2010.859] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2010] [Accepted: 10/25/2010] [Indexed: 11/06/2022] Open
Abstract
Cancer cells usually obtain energy from a high rate of glycolysis rather than oxidative phosphorylation under normoxia as well as hypoxia. Under these circumstances, pyruvate, the end-product of glycolysis, accumulates in cancer cells. We have previously reported that pyruvate activates endothelial cells and induces angiogenesis. Here, we examined the angiogenic activity of pyruvate in tumor cells. Plasminogen activator inhibitor-1 (PAI-1), the gene most upregulated by pyruvate, showed a pro-angiogenic activity, which was abolished by a PAI-1 neutralizing antibody. Moreover, stabilization of hypoxia-inducible factor-1α (HIF-1α) by pyruvate was required for induction of PAI-1 transcription through direct binding to hypoxia response element-2 (HRE-2) on the promoter. These results suggest that pyruvate can activate the angiogenic activity of cancer cells under normoxia and that PAI-1 may act as a pro-angiogenic factor in pyruvate-induced angiogenesis.
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Affiliation(s)
- Seung-Youn Jung
- Department of Molecular Biology, College of Natural Science, Pusan National University, Busan 609-735, Republic of Korea
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22
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Abstract
Pigeons were trained to peck either of two response keys for food reinforcement on equated aperiodic schedules. The distribution of responding at the two keys was studied as reinforcement was delayed for various durations. The relative frequency of responding at each key was shown to match the relative immediacy of reinforcement, immediacy defined as the reciprocal of the delay of reinforcement.
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Abstract
When a variable-interval schedule of reinforcement was segmented into small fixed-interval components, with reinforcements following some components and brief blackouts following the others, rate of responding doubled and a positively accelerated pattern within each component was obtained. Presented according to this percentage reinforcement paradigm, the blackouts approximated the functions of a food reinforcer. These effects occurred only when the behavior sequence required to produce reinforcement was identical to that required to produce blackout. The quasi-reinforcing effects of these blackout stimuli suggest that a neutral stimulus need not occasion or accompany a primary reinforcer to acquire reinforcing properties.
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Chung SH, Cerussi AE, Merritt SI, Ruth J, Tromberg BJ. Non-invasive tissue temperature measurements based on quantitative diffuse optical spectroscopy (DOS) of water. Phys Med Biol 2010; 55:3753-65. [PMID: 20551502 DOI: 10.1088/0031-9155/55/13/012] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We describe the development of a non-invasive method for quantitative tissue temperature measurements using Broadband diffuse optical spectroscopy (DOS). Our approach is based on well-characterized opposing shifts in near-infrared (NIR) water absorption spectra that appear with temperature and macromolecular binding state. Unlike conventional reflectance methods, DOS is used to generate scattering-corrected tissue water absorption spectra. This allows us to separate the macromolecular bound water contribution from the thermally induced spectral shift using the temperature isosbestic point at 996 nm. The method was validated in intralipid tissue phantoms by correlating DOS with thermistor measurements (R=0.96) with a difference of 1.1+/-0.91 degrees C over a range of 28-48 degrees C. Once validated, thermal and hemodynamic (i.e. oxy- and deoxy-hemoglobin concentration) changes were measured simultaneously and continuously in human subjects (forearm) during mild cold stress. DOS-measured arm temperatures were consistent with previously reported invasive deep tissue temperature studies. These results suggest that DOS can be used for non-invasive, co-registered measurements of absolute temperature and hemoglobin parameters in thick tissues, a potentially important approach for optimizing thermal diagnostics and therapeutics.
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Affiliation(s)
- S H Chung
- Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104, USA
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Chung SH, Son SJ, Min J. The nanostructure effect on the adhesion and growth rates of epithelial cells with well-defined nanoporous alumina substrates. Nanotechnology 2010; 21:125104. [PMID: 20195010 DOI: 10.1088/0957-4484/21/12/125104] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We systematically analyzed the adhesion and the proliferation of cells on various nanoporous alumina surfaces to understand the effects of nanostructured surfaces on cell behavior. Various nanoporous surfaces were fabricated using the anodizing method and characterized by atomic force microscopy and scanning electron microscopy. The adhesion rate and proliferation rate of cells as functions of pore size and depth were statistically investigated using a colorimetric method. The adhesion rate of cells was not affected by the depth of the nanoporous surface whereas the proliferation of cells dramatically increased when the aspect ratio of the nanopore was near unity. This phenomenon was further verified by comparing the change in roughness of the cytoplasmic layer of cells adhered on a nanoporous surface with that of a bare nanoporous surface. The proliferation of cells was also influenced by the pore size of the nanoporous surface because the nanostructure could control the interaction between extracellular matrix (ECM) molecules and the surface. In conclusion, the nanostructured surfaces affected cell adhesion and proliferation by increasing the surface area to which the cells could adhere, and the interactions between small ECM molecules were influenced by the sufficiently small structures of the nanosurface.
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Affiliation(s)
- S H Chung
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul, Korea
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Patel S, Chung SH, White G, Bao S, Celermajer DS. The "atheroprotective" mediators apolipoprotein A-I and Foxp3 are over-abundant in unstable carotid plaques. Int J Cardiol 2009; 145:183-187. [PMID: 19481824 DOI: 10.1016/j.ijcard.2009.05.024] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2009] [Revised: 04/10/2009] [Accepted: 05/12/2009] [Indexed: 02/05/2023]
Abstract
OBJECTIVE Inflammation is important in plaque vulnerability but the role of atheroprotective mediators in unstable plaques is not defined. The apolipoproteinA-I (apoA-I) component of HDL, and CD4+/CD25+ regulatory T cells (with their major transcription factor, Foxp3), have been implicated in the suppression of vascular inflammation. Our aim was to characterise the presence of these novel "protective" markers (apoA-I and Foxp3) in carotid plaques from symptomatic and asymptomatic subjects. METHODS AND RESULTS Plaques from 57 patients (25 symptomatic, 32 asymptomatic) were stained immunohistochemically for macrophages (CD68), T cells (CD3), monocyte chemotactic protein-1 (MCP-1), matrix metalloproteinase-2 (MMP-2), myeloperoxidase (MPO), apoA-I and Foxp3. Twelve randomly selected plaques (6 asymptomatic, 6 symptomatic) were immunostained for interleukin-10 (IL-10) and interleukin-17 (IL-17). Staining was quantified using Image-Pro Plus software. Significantly greater areas of positive immunostaining for CD68, CD3, MCP-1, MMP-2, IL-17 and MPO were found in plaques from symptomatic patients compared with asymptomatic patients (p<0.05 for all). Furthermore, significantly greater areas of positive immunostaining for apoA-I, Foxp3 and IL-10 were found in symptomatic versus asymptomatic plaques (p<0.05 for all). The presence of apoA-I was correlated significantly and co-localised with CD3, CD68, MCP-1, MMP-2 and MPO immunostaining (R=0.70, 0.63, 0.52, 0.55 and 0.79, respectively; p<0.01 for all). Foxp3 immunostaining also correlated significantly with CD3 (R=0.42), CD68 (R=0.47), MCP-1 (R=0.55) and MMP-2 (R=0.44) immunostaining (p<0.05 for all). CONCLUSIONS ApoA-I and Foxp3 are over-abundant in plaques from symptomatic subjects and co-localise with key inflammatory mediators. These data suggest ineffective/insufficient protection against atherosclerosis-mediated inflammation by these "atheroprotective" moieties.
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Affiliation(s)
- S Patel
- Department of Cardiology, Royal Prince Alfred Hospital, Sydney, Australia; Discipline of Medicine, University of Sydney, Sydney, Australia; Discipline of Pathology, Bosch Institute, University of Sydney, Sydney, Australia.
| | - S H Chung
- Discipline of Pathology, Bosch Institute, University of Sydney, Sydney, Australia
| | - G White
- Department of Vascular Surgery, Royal Prince Alfred Hospital, Sydney, Australia; Discipline of Surgery, University of Sydney, Sydney, Australia
| | - S Bao
- Discipline of Pathology, Bosch Institute, University of Sydney, Sydney, Australia
| | - D S Celermajer
- Department of Cardiology, Royal Prince Alfred Hospital, Sydney, Australia; Discipline of Medicine, University of Sydney, Sydney, Australia
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Chung SH, Cerussi AE, Klifa C, Baek HM, Birgul O, Gulsen G, Merritt SI, Hsiang D, Tromberg BJ. In vivo water state measurements in breast cancer using broadband diffuse optical spectroscopy. Phys Med Biol 2008; 53:6713-27. [PMID: 18997265 DOI: 10.1088/0031-9155/53/23/005] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Structural changes in water molecules are related to physiological, anatomical and pathological properties of tissues. Near infrared (NIR) optical absorption methods are sensitive to water; however, detailed characterization of water in thick tissues is difficult to achieve because subtle spectral shifts can be obscured by multiple light scattering. In the NIR, a water absorption peak is observed around 975 nm. The precise NIR peak's shape and position are highly sensitive to water molecular disposition. We introduce a bound water index (BWI) that quantifies shifts observed in tissue water absorption spectra measured by broadband diffuse optical spectroscopy (DOS). DOS quantitatively measures light absorption and scattering spectra and therefore reveals bound water spectral shifts. BWI as a water state index was validated by comparing broadband DOS to magnetic resonance spectroscopy, diffusion-weighted MRI and conductivity in bound water tissue phantoms. Non-invasive DOS measurements of malignant and normal breast tissues performed in 18 subjects showed a significantly higher fraction of free water in malignant tissues (p < 0.0001) compared to normal tissues. BWI of breast cancer tissues inversely correlated with Nottingham-Bloom-Richardson histopathology scores. These results highlight broadband DOS sensitivity to molecular disposition of water and demonstrate the potential of BWI as a non-invasive in vivo index that correlates with tissue pathology.
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Affiliation(s)
- S H Chung
- Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Road, Irvine, CA 92612, USA
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Shin YK, Yoon IY, Han EK, No YM, Hong MC, Yun YD, Jung BK, Chung SH, Choi JB, Cyn JG, Lee YJ, Hong SC. Prevalence of narcolepsy-cataplexy in Korean adolescents. Acta Neurol Scand 2008; 117:273-8. [PMID: 17922892 DOI: 10.1111/j.1600-0404.2007.00930.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Narcolepsy typically begins between adolescence and early adulthood causing severe neuropsychiatric impairments, but few prevalence studies are available on adolescent narcoleptics. In the present study, we investigated the prevalence of narcolepsy-cataplexy in adolescents. METHODS In total 20,407 students, aged 14-19 years, participated in this study. Ullanlinna Narcolepsy Scale (UNS) was applied to all subjects and those with a UNS score of > or =14 were contacted by phone for semi-structured interview. Subjects then suspected of having narcolepsy participated in a laboratory investigation, which included polysomnography and HLA typing, or were interviewed in detail by telephone. RESULTS Three subjects were finally diagnosed as narcolepsy with cataplexy and seven subjects might be diagnosed as narcolepsy without cataplexy. Among three narcoleptics with cataplexy, two subjects were HLA-DQB1*0602 and DRB1*1501 positive, but one subject had no test of HLA typing. The prevalence of narcolepsy with cataplexy in Korean adolescence was thus determined to be 0.015% (95% confidence interval = 0.0-0.0313%). CONCLUSION This epidemiologic study is the first of its type on adolescent narcolepsy to use the International Classification of Sleep Disorders, 2nd edition (ICSD-2) diagnostic criteria. Considering those cases with an onset after adolescence were not included, the prevalence of narcolepsy with cataplexy determined in the present study is comparable with that of other studies in adults.
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Affiliation(s)
- Y K Shin
- Department of Psychiatry, St Vincent's Hospital, The Catholic University of Korea, Suwon, Korea
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Kim KO, Choe G, Chung SH, Kim CS. Delayed pharmacological pre-conditioning effect of mitochondrial ATP-sensitive potassium channel opener on neurologic injury in a rabbit model of spinal cord ischemia. Acta Anaesthesiol Scand 2008; 52:236-42. [PMID: 18005376 DOI: 10.1111/j.1399-6576.2007.01534.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND Diazoxide, pharmacological openers of mitochondrial ATP-sensitive potassium channels have been shown to induce early pre-conditioning in the spinal cord. Here, the authors investigated whether diazoxide also induce delayed pre-conditioning and thereby reduce neurologic complications using a rabbit model of spinal cord ischemia. METHODS Infrarenal blood flow was interrupted for 20 min in 21 rabbits. Non-treated control animals received no pre-treatment. Diazoxide (5 mg/kg) were given 48 h before 20 min ischemia in the 48-h DZ group, whereas 15-min DZ group received diazoxide (5 mg/kg) 15 min before 20-min ischemia. Neurological functions were evaluated using Johnson scores for 3 days after reperfusion, after which, spinal cords were procured for hematoxylin and eosin staining for cell counting. RESULTS Johnson scores revealed a marked improvement in both the diazoxide-treated groups vs. the non-treated control group at 3, 24, 48, and 72 h after reperfusion (P<0.01). The histologic changes were proportional to the Johnson scores, with better preservation of motor neuron numbers in the animals of the 48-h DZ and 15-min DZ group relative to the non-treated controls (81+/-12, 90+/-10, 50+/-23 motor neurons, respectively, P<0.01). No difference was found between the 48-h DZ group and 15-min DZ group with respect to the Johnson scores or neuron numbers. CONCLUSIONS The study demonstrates that pre-treatment with diazoxide 48 h before ischemia, induce delayed pharmacological pre-conditioning, thereby significantly improving clinical neurologic scores and histologic findings in this animal model.
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Affiliation(s)
- K O Kim
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Korea.
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Noh H, Kim JS, Han KH, Lee GT, Song JS, Chung SH, Jeon JS, Ha H, Lee HB. Oxidative stress during peritoneal dialysis: implications in functional and structural changes in the membrane. Kidney Int 2006; 69:2022-8. [PMID: 16641917 DOI: 10.1038/sj.ki.5001506] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Progressive peritoneal fibrosis, membrane hyperpermeability, and ultrafiltration failure have been observed in patients on long-term peritoneal dialysis (PD). The present study tested the hypothesis that reactive oxygen species (ROS) generated by conventional PD solution (PDS) mediate functional and structural alterations of peritoneal membrane in vivo. Sprague-Dawley rats were randomized to control, PDS, PDS with an antioxidant, and PDS with an angiotensin II (Ang II) receptor blocker. Commercial PDS containing 3.86% glucose (20-30 ml) with or without N-acetylcystein (NAC) 10 mM or losartan 5 mg/kg was administered intraperitoneally twice a day for 12 weeks. Control rats received sham injection. Rats treated with PDS had significantly lower drain volume and D(4)/D(0) glucose, but higher D(4)/P(4) creatinine and increased membrane thickness and endothelial NOS (eNOS) expression compared to control rats. Omental transforming growth factor (TGF)-beta1, vascular endothelial growth factor (VEGF), collagen I, and heat-shock protein (hsp) 47 expression and lipid peroxide levels and dialysate VEGF and Ang II concentrations were significantly increased in rats treated with PDS compared to control. All of these changes were prevented by both NAC and losartan. In conclusion, the present study demonstrates that ROS generated by conventional PDS are, in large part, responsible for peritoneal fibrosis and membrane hyperpermeability. We suggest that antioxidants or Ang II receptor blockers may allow better preservation of the structural and functional integrity of the peritoneal membrane during long-term PD.
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Affiliation(s)
- H Noh
- Hyonam Kidney Laboratory, Soon Chun Hyang University, Seoul, Korea
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Jeong YG, Chung SH, Kim CT, Kim KH, Han SY, Hyun BH, Lee NS, Sawada K, Won MH, Fukui Y. Corticotropin-Releasing Factor Immunoreactivity Increases in the Cerebellar Climbing Fibers in the Novel Ataxic Mutant Mouse, Pogo. Anat Histol Embryol 2006; 35:111-5. [PMID: 16542176 DOI: 10.1111/j.1439-0264.2005.00646.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The ataxic pogo mouse (pogo/pogo) is a novel neurological mutant, which was derived as an inbred strain (KJR/MsKist) from a Korean wild mouse. The pathological manifestations include a difficulty in maintaining a normal posture, the failure of inter-limb coordination and an inability to walk straight. In this study, we examined the distribution of corticotropin-releasing factor (CRF) immunoreactive cerebellar climbing fibres and their projections to tyrosine hydroxylase (TH) immunoreactive Purkinje cells in the cerebellum of the pogo mutant mouse using immunohistochemistry. In the pogo/pogo mouse, a subset of climbing fibres was stained more intensely for CRF than in the control. Moreover, ataxic pogo mouse, neurons of the inferior olivary nucleus projecting climbing fibres were also more intensely stained for CRF than in the control. In the pogo/pogo mouse, TH immunoreactivity was located in the Purkinje cells, whereas no TH expression was found in the control. Double immunostaining for CRF and TH in the pogo/pogo cerebellum revealed that the distribution of TH-immunoreactive Purkinje cells corresponded to terminal fields of CRF-immunoreactive climbing fibres but not to the CRF-immunoreactive mossy fibres. Therefore, we suggest that an increase of CRF level may alter the function of targeted Purkinje cells and that it is related to the ataxic phenotype in the pogo mutant mouse.
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Affiliation(s)
- Y G Jeong
- Department of Anatomy, College of Medicine, Konyang University, Nonsan, Chungnam 320-711, South Korea.
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Yao Q, Wang X, Chung SH, Pecoits-Filho R, Stenvinkel P, Wang T, Heimbürger O, Lindholm B. The role of peritoneal dialysis in renal replacement therapy: an update on medical aspects. Panminerva Med 2005; 47:19-30. [PMID: 15985974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
In this brief review, we discuss various medical factors that are of importance for the role of peritoneal dialysis (PD) in renal replacement therapy (RRT), whereas the complex role of non medical factors will only be mentioned briefly. The aim of any RRT, including hemodialysis, PD and renal transplantation, is to normalize the volume and composition of the body fluids, to remove uremic toxins, and to improve clinical outcome. In the following, we will focus on adequacy, preservation of residual renal function, fluid balance, infections, nutrition, cardiovascular disease and systemic inflammation in PD as these factors are strong predictors of clinical outcome in end stage renal disease patients.
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Affiliation(s)
- Q Yao
- Division of Baxter Novum, Department of Clinical Sciences, Karolinska Institutet, Huddinge University Hospital, Stockholm, Sweden
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Shin SS, Jin M, Jung HJ, Kim B, Jeon H, Choi JJ, Kim JM, Cho BW, Chung SH, Lee YW, Song YW, Kim S. Suppressive effects of PG201, an ethanol extract from herbs, on collagen-induced arthritis in mice. Rheumatology (Oxford) 2003; 42:665-72. [PMID: 12709543 DOI: 10.1093/rheumatology/keg209] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE PG201 has been formulated using 12 herbs known to have anti-inflammatory and protective effects on damaged tissue and bone among other functions. The present study was done in order to assess the therapeutic effects of PG201 in collagen-induced arthritis (CIA) in mice. METHODS DBA/1 mice were immunized with bovine type II collagen. After a second collagen immunization, mice were treated with PG201 orally at 10 mg/kg once a day for 18 days. Paws were evaluated macroscopically for redness, swelling and deformities. The levels of TNF-alpha and IL-1beta in the ankle were examined. The severity of arthritis within the knee joints was evaluated by histological assessment of cartilage destruction and pannus formation. Molecular indicators related to CIA pathology were analysed by measuring the serum levels of matrix metalloproteinase 2 (MMP-2), tissue inhibitor of matrix metalloproteinase 2 (TIMP-2) and the anti-inflammatory cytokines interleukin (IL)-4 and IL-10. RESULTS Administration of PG201 significantly suppressed the progression of CIA and inhibited the production of TNF-alpha and IL-1beta in the paws. The erosion of cartilage was dramatically reduced in mouse knees after treatment with PG201. In the serum of PG201-treated mice, the level of TIMP-2 and the ratio of TIMP-2 to MMP-2 were significantly elevated, and the level of IL-4, but not of IL-10, was increased. CONCLUSION Administration of PG201 has therapeutic effects on CIA. Protection of cartilage was particularly prominent. PG201 is a potential therapy for rheumatoid arthritis.
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Affiliation(s)
- S S Shin
- PanGenomics Co. Limited, Biotechnology Incubating Center, Seoul National University, Seoul 151-742, Korea
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Chung SH, Muñoz M, García N, Egelhoff WF, Gomez RD. Universal scaling of ballistic magnetoresistance in magnetic nanocontacts. Phys Rev Lett 2002; 89:287203. [PMID: 12513177 DOI: 10.1103/physrevlett.89.287203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2002] [Indexed: 05/24/2023]
Abstract
We show that ballistic magnetoresistance exhibits universal scaling in atomic or nanometer scale contacts. Plotting the data as conductance, we find that, if the maximum magnetoconductance is normalized to unity and the conductance is scaled with the conductivity of the bulk material, the data fall in a narrow region, independent of the nanocontact materials, for our four data sets and four from the literature. The results agree with a theory that takes into account spin-scattering within a magnetic-domain wall.
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Affiliation(s)
- S H Chung
- Electrical and Computer Engineering Department and Physics Department, University of Maryland, College Park, Maryland 20742 and Laboratory for Physical Sciences, College Park, Maryland 20740, USA
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Jeong YG, Lee NS, Chung SH, Lee KY, Suh JG, Hyun BH, Kang TC, Oh YS, Won MH. Morphological characteristics of C1 and C2 adrenergic neurone groups in marmoset monkey brainstem by using antibody against phenylethanolamine-N-methyltransferase. Anat Histol Embryol 2002; 31:375-7. [PMID: 12693759 DOI: 10.1046/j.1439-0264.2002.00424.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This work describes a mapping study of phenylethanolamine-N-methyltransferase (PNMT) immunoreactive neurones and fibres in the medulla oblongata of the marmoset monkey, Callithrix jacchus. Two groups of PNMT-immunoreactive neurones were found in the marmoset monkey medulla oblongata: a ventrolateral (C1 group) and a dorsomedial PNMT-immunoreactive cells group (C2 group). The PNMT-immunoreactive cells in the ventrolateral group C1 were found to be located around the lateral reticular nucleus. The PNMT-immunoreactive somata within the ventrolateral medulla are round to oval, and mostly multipolar with branched processes. In the dorsomedial group C2, PNMT-immunoreactive cell bodies appeared near the obex. The majority of the dorsomedial PNMT-immunoreactive neurones were observed in the nucleus tractus solitarius; although some were present in the dorsal motor nucleus of the vagus. The PNMT-immunoreactive somata in the dorsomedial medulla were small and round or ovoid. These results provide information upon the adrenergic system in the medulla oblongata of a species that presents a useful model of a small primate brain, the marmoset monkey.
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Affiliation(s)
- Y G Jeong
- Department of Anatomy, College of Medicine, Hallym University, Chunchon 200-702, Republic of Korea
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Stenvinkel P, Chung SH, Heimbürger O, Lindholm B. Malnutrition, inflammation, and atherosclerosis in peritoneal dialysis patients. Perit Dial Int 2002; 21 Suppl 3:S157-62. [PMID: 11887812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023] Open
Affiliation(s)
- P Stenvinkel
- Department of Nephrology and Baxter Novum, Huddinge University Hospital, Stockholm, Sweden.
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Park WS, Chang YS, Chung SH, Seo DW, Hong SH, Lee M. Effect of hypothermia on bilirubin-induced alterations in brain cell membrane function and energy metabolism in newborn piglets. Brain Res 2001; 922:276-81. [PMID: 11743960 DOI: 10.1016/s0006-8993(01)03186-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The aim of this study was to evaluate the effects of hypothermia on bilirubin-induced alterations in brain cell membrane function and energy metabolism in the developing brain. Thirty-seven newborn piglets were divided randomly into four groups: normothermic control (NC, n=9); hypothermic control (HC, n=7); normothermic bilirubin infusion (NB, n=11); and hypothermic bilirubin infusion (HB, n=10) groups. In bilirubin infusion groups (NB and HB), a loading dose of bilirubin (35 mg/kg) was given over 5 min, followed by a continuous infusion (25 mg/kg/h) for 4 h. The control groups (NC, HC) received a bilirubin-free buffer solution. Sulfadimethoxine was administered to animals in all experimental groups. Rectal temperature was maintained between 38.0 and 39.0 degrees C in normothermic groups, and between 34.0 and 35.0 degrees C in hypothermic groups for 4 h after the start of bilirubin infusion. The final blood and brain bilirubin concentrations in the bilirubin infusion groups (NB and HB) were not significantly different. Decreased cerebral cortical cell membrane Na(+),K(+)-ATPase activity and increased lipid peroxidation products observed in the NB group, indicative of bilirubin-induced brain damage, were significantly attenuated in the HB group. Hypothermia also significantly improved the bilirubin-induced reduction in brain ATP and phosphocreatine levels and increase in blood and brain lactate levels. In summary, hypothermia significantly attenuated the bilirubin-induced alterations in brain cell membrane function and energy metabolism in the newborn piglet. These findings suggest the possibility that hypothermia could be a good neuroprotective therapeutic modality in neonatal bilirubin encephalopathy.
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Affiliation(s)
- W S Park
- Department of Pediatrics, Samsung Medical Center, 50 Ilwon-Dong, Kangnam-Gu, Sungkyunkwan University School of Medicine, Seoul, South Korea
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Abstract
Three-dimensional Brownian dynamics simulations are used to study conductance of the KcsA potassium channel using the known crystallographic structure. Employing an open-state channel created by molecular dynamics simulations, current-voltage and current-concentration curves broadly consistent with experimental measurements are obtained. In the absence of an applied potential, the channel houses three potassium ions at positions that are in close agreement with X-ray diffraction maps.
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Affiliation(s)
- T W Allen
- Department of Physics, Australian National University, 0200, Canberra, ACT, Australia
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Chung SH, Heimbürger O, Stenvinkel P, Bergström J, Lindholm B. Association between inflammation and changes in residual renal function and peritoneal transport rate during the first year of dialysis. Nephrol Dial Transplant 2001; 16:2240-5. [PMID: 11682675 DOI: 10.1093/ndt/16.11.2240] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Peritoneal transport rate, a major determinant of peritoneal dialysis (PD) patient survival, increases in most patients starting on PD, while in other patients peritoneal transport rate may decline. Although several factors may contribute to changes in peritoneal transport rate, inflammation is known to be associated with a high peritoneal transport rate, and residual renal function (RRF), which often declines after start of PD, may also be related to inflammation. Therefore, we hypothesized that changes in peritoneal transport rate during patients' first year on PD and declining RRF may be linked with inflammation. METHODS A total of 76 PD patients (40 males, mean age 56.8+/-14.1 years), who underwent two peritoneal equilibration tests at a mean of 0.4 months and 1 year after beginning PD, were included in the study. Based on the change in dialysate to plasma creatinine concentration ratio at 4-h dwell (D/P Cr) during first year on PD, the patients were divided into decreased or unchanged (group DUC; n=22) and increased (group I; n=54) groups. RESULTS Initially, group I had a lower proportion of high transporters and more often high serum C-reactive protein (sCRP, > or =10 mg/l) and lower RRF compared with the DUC group. In group I, serum albumin and RRF decreased significantly and dialysate protein loss and glucose absorption increased significantly during the first year on PD. When patients were divided into two groups based on median change in RRF (1.9 ml/min), patients with a decrease in RRF >1.9 ml/min during first year on PD had a higher proportion of high sCRP, higher D/P Cr, and higher changes in D/P Cr compared to patients with a decrease in RRF < or =1.9 ml/min. Patients with elevated sCRP at one year included a higher proportion of patients who had high sCRP at the start of PD, higher increase in D/P Cr, lower serum albumin, lower RRF, and more decrease in RRF during first year on PD compared with patients having normal sCRP. RRF was inversely correlated with changes in D/P Cr during the first year on PD (r=-0.28, P=0.02). Multiple regression analysis revealed that the only factors affecting changes in D/P Cr were high sCRP and a low RRF. CONCLUSIONS Our preliminary short-term study suggests that changes in peritoneal transport rate during patients' first year on PD may be linked with inflammation and declining residual renal function. Inflammation and residual renal function were identified as the only independent factors determining peritoneal transport rate during the first year on PD. It is possible that inflammation may cause both an increase in peritoneal transport rate and a decline in residual renal function, or that the decline in residual renal function and the increase in peritoneal transport rate may induce or aggravate inflammation. Further studies are needed to confirm these findings.
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Affiliation(s)
- S H Chung
- Division of Baxter Novum and Renal Medicine, Department of Clinical Science, Karolinska Institute, Huddinge University Hospital, Stockholm, Sweden
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Abstract
Diabetic nephropathy is the leading cause of end-stage renal disease worldwide. Although death rates of diabetic patients on hemodialysis and peritoneal dialysis (PD) have decreased substantially, they remain higher than rates in nondiabetics on both modalities. PD offers equal or better survival than hemodialysis for younger diabetic patients during early years of dialysis. PD technique survival does not appear different between diabetic and nondiabetic patients but is inferior to hemodialysis technique survival. PD may accelerate changes in peritoneal membrane structure and function in diabetics. Peritonitis and conventional PD solutions containing high glucose and glucose degradation products are implicated in PD technique failure. Increased peritoneal expression of vascular endothelial growth factor and transforming growth factor-beta1 and excessive accumulation of advanced glycosylation end products may be involved in the progressive increase in membrane permeability, loss of ultrafiltration, and peritoneal fibrosis. Nonglucose PD solutions or solutions containing low glucose degradation products may prevent or delay alterations in peritoneal membrane structure and function in diabetic as well as nondiabetic patients during long-term PD.
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Affiliation(s)
- H B Lee
- Hyonam Kidney Laboratory, Soon Chun Hyang University, Seoul, Korea.
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Abstract
The purpose of this study was twofold. To evaluate whether prostaglandin El can increase the survival of the flap, and to determine its function against ischemia-reperfusion injury in musculocutaneous flaps. Thirty-five Sprague-Dawley rats weighing 250 to 350 g were analyzed. The transverse rectus abdominis musculocutaneous flap was used in all rats. The rats were divided into three groups: group 1 (N = 15), the control group with 4-hour ischemic injury and intraflap injection of normal saline followed by reperfusion; group 2 (N = 15), prostaglandin E1 intraflap injection of 1 microg immediately after ischemic injury and reperfusion 4 hours later; and group 3 (N = 5), the sham-operated group. Analysis consisted of flap skin survival area measurements, immunohistochemical study using anti-intercellular adhesion molecule (anti-ICAM-1) monoclonal antibody, and histological evaluation including endothelium-sticking leukocytes at 24 hours and 5 days after reperfusion. The group treated with prostaglandin E1 showed immunohistochemical findings with decreased expression of ICAM-1 on the surface of the endothelium, and histology showed significant (p < 0.01) reduction of leukocyte adhesion at 24 hours and 5 days after reperfusion. These two factors were considered to play a role against ischemia-reperfusion injury, and led to improved survival of the flap. These results suggest that prostaglandin E1 may increase flap survival and may have a protective mechanism against ischemia-reperfusion injury by decreasing leukocyte-endothelial cell adhesion through decreased expression of ICAM-1.
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Affiliation(s)
- J P Hong
- Department of Plastic and Reconstructive Surgery, Yonsei University Wonju College of Medicine, Kangwondo, Korea
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Chung SH, Stenvinkel P, Bergström J, Lindholm B. Biocompatibility of new peritoneal dialysis solutions: what can we hope to achieve? Perit Dial Int 2001; 20 Suppl 5:S57-67. [PMID: 11229614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
Despite the bioincompatibility of the "old", standard, high glucose, lactate-buffered peritoneal dialysis (PD) solutions, PD is itself a highly successful dialysis modality with patient survival equivalent to that of hemodialysis (HD) during the initial 3 - 5 years of dialysis therapy. Nevertheless, PD technique survival is often limited by infectious complications and alterations in the structure and function of the peritoneal membrane. These local changes also have a negative impact on patient survival owing to systemic effects such as those often seen in patients with high peritoneal transport rate and loss of ultrafiltration (UF) capacity. Patient mortality remains unacceptably high in both HD and PD patients, with most premature deaths being associated with signs of malnutrition, inflammation, and atherosclerotic cardiovascular disease (MIA syndrome). These systemic signs are likely to be influenced by PD solutions both directly and indirectly (via changes in the peritoneal membrane). New, biocompatible PD solutions may have favorable local effects (viability and function of the peritoneal membrane) and systemic effects (for example, on MIA syndrome). Amino acid-based solution [Nutrineal (N): Baxter Healthcare Corporation, Deerfield, IL, U.S.A.] may improve nutritional status as well as peritoneal membrane viability. Bicarbonate/lactate-buffered solution [Physioneal (P): Baxter Healthcare Corporation] may ameliorate local and systemic effects of low pH, high lactate, and high glucose degradation products. Icodextrin-based solution [Extraneal (E): Baxter Healthcare SA, Castlebar, Ireland] may improve hypertension and cardiovascular problems associated with fluid overload and may extend time on therapy in patients with loss of UF capacity. The positive effects of each of these new, biocompatible solutions have been demonstrated in several studies. It is likely that the combined use of N, P, and E solutions will produce favorable synergies in regard to both local effects (peritoneal viability) and systemic effects (less malnutrition, inflammation, and fluid overload). Solution combination is an exciting area for clinical study in the coming years. Furthermore, dialysis fluid additives such as hyaluronan, which protects and improves the function of the peritoneal membrane, may further improve PD solutions. The new, biocompatible PD solutions represent an entirely new era in the evolution of the PD therapy; they are likely to have markedly positive effects on both PD technique and PD patient survival in coming years.
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Affiliation(s)
- S H Chung
- Department of Clinical Science, Karolinska Institute, Stockholm, Sweden
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Abstract
Four ellagic acid rhamnosides were isolated from the stem bark of Eucalyptus globulus. Their structures have been established on the basis of the analysis of their 1H NMR, 13C NMR, HMBC, IR and MS spectral data. The HMBC data of these compounds were most useful for their structure determinations, with these bring determined to be 3-O-methylellagic acid 3'-O-alpha-rhamnopyranoside, 3-O-methylellagic acid 3'-O-alpha-3''-O-acetylrhamnopyranoside, 3-O-methylellagic acid 3'-O-alpha-2''-O-acetylrhamnopyranoside, 3-O-methylellagic acid 3'-O-alpha-4''-O-acetylrhamnopyranoside, respectively. Their antioxidant activities were evaluated by measuring the inhibition of lipid peroxidation using rat liver microsomes, with IC50 values of 10.0-14.0 microg/ml.
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Affiliation(s)
- J P Kim
- Korea Research Institute of Bioscience and Biotechnology, Yusong, Taejon, South Korea
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Abstract
The mechanisms responsible for the antidiabetic activity of both the white ginseng radix (Ginseng Radix Alba, GRA) and the rootlet (Ginseng Radix Palva, GRP) were investigated. After a four week oral administration, the fasting blood glucose levels in the GRA- and GRP-treated groups were lower when compared to the control group. To elucidate the hypoglycemic mechanism(s) of the ginseng radices, glucose absorption from the small intestine, hepatic hexokinase and glucose-6-phosphatase activities, in addition to PPAR-gamma expression in adipose tissue were examined. The results strongly suggest that GRA can improve hyperglycemia in KKAy mice, possibly by blocking intestinal glucose absorption and inhibiting hepatic glucose-6-phosphatase, and GRP through the upregulation of adipocytic PPAR-y protein expression as well as inhibiting intestinal glucose absorption.
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Affiliation(s)
- S H Chung
- Kyung Hee University, School of Pharmacy, Seoul, Korea.
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Abstract
OBJECTIVES To verify the dose-response relationship in phenol nerve block and to determine the concentration and volume of phenol injectate required for effective nerve conduction block. DESIGN Before-after, experimental study. SETTING A research institute laboratory. ANIMALS Seventy-one New Zealand white rabbits. INTERVENTIONS Group I (n = 48) received tibial nerve block by perineural injection (phenol, n = 40; saline, n = 8), group II (n = 21) by submerging the nerve in phenol solution. The 6 subgroups of group I each received different concentrations (3%, 4%, 5%) and volumes (0.1mL, 0.2mL, 0.3mL). The 2 subgroups of group II received 3% (n = 8) and 5% (n = 13) phenol. MAIN OUTCOME MEASURES Compound muscle action potential (CMAP) and tension of triceps surae muscles by electric stimulation of the sciatic nerve were measured preintervention and at day 1, and weeks 1, 2, 4, and 8 postblock. Histologic studies were performed on 2 animals from group I. RESULTS Two rabbits in group I died before results were obtained. In the remaining animals, CMAP amplitude reduced significantly (p <.05) as the volume of 5% phenol solution increased from 0.1mL, 0.2mL, to 0.3mL. A high concentration of phenol produced a more pronounced conduction block; however, no significant (p =.0589) difference existed among the 3 concentrations. Submerged tibial nerve had a greater degree of conduction block than perineurally injected nerve. Depth of the degeneration area in nerve fascicle varied with distance from the injection point. CONCLUSIONS The nerve block effect of phenol can be titrated by adjusting the concentration and volume of phenol solution if the technique of application and localization of a block site are standardized.
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Affiliation(s)
- D H Sung
- Department of Physical Medicine and Rehabilitation, Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul National University College of Medicine, Korea.
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Abstract
The mechanisms underlying ion transport and selectivity in calcium channels are examined using electrostatic calculations and Brownian dynamics simulations. We model the channel as a rigid structure with fixed charges in the walls, representing glutamate residues thought to be responsible for ion selectivity. Potential energy profiles obtained from multi-ion electrostatic calculations provide insights into ion permeation and many other observed features of L-type calcium channels. These qualitative explanations are confirmed by the results of Brownian dynamics simulations, which closely reproduce several experimental observations. These include the current-voltage curves, current-concentration relationship, block of monovalent currents by divalent ions, the anomalous mole fraction effect between sodium and calcium ions, attenuation of calcium current by external sodium ions, and the effects of mutating glutamate residues in the amino acid sequence.
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Affiliation(s)
- B Corry
- Protein Dynamics Unit, Department of Chemistry, Australian National University, Canberra, Australian Capital Territory
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Abstract
1. The transport process of ions across the potassium channel is studied using computer simulations. The shape of the model channel corresponds closely to that deduced from crystallography. 2. We first give an intuitive account of how the motion of ions experiencing an applied electric force and interacting with a dielectric boundary and charge residues on the channel wall can be simulated accurately by using a powerful supercomputer. 3. We then show how some of the salient features of ion channels can be deduced by following the positions of ions at each discrete step over many millions of time steps.
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Affiliation(s)
- S H Chung
- Department of Chemistry, Research School of Physical Sciences, Australian National University, Canberra, Australian Capital Territory.
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Abstract
We propose a model of calcium channels that can explain most of their observed properties, including the anomalous mole fraction effect and mutation of the glutamate residues. The structure grossly resembles that of the KcsA potassium channel except for the presence of an extracellular vestibule and a shorter selectivity filter containing four glutamate residues. Using this model in electrostatic calculations and Brownian dynamics simulations, we study mechanisms of ion permeation and selectivity in the channel. Potential energy profiles calculated for multiple ions in the channel provide explanations of ion permeation, the block of Na(+) currents by Ca(2+) ions, and many other observed properties. Brownian dynamics simulations provide quantitative predictions for the channel currents which reproduce available experimental data.
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Affiliation(s)
- B Corry
- Protein Dynamics Unit, Department of Chemistry, Research School of Physical Sciences, Australian National University, Canberra
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Park MS, Yim AS, Chung SH, Lee EY, Cha MK, Kim JH, Song KI, Han DC, Hwang SD, Moon C, Lee HB. Effect of prolonged subcutaneous implantation of peritoneal catheter on peritonitis rate during CAPD: a prospective randomized study. Blood Purif 2000; 16:171-8. [PMID: 9681160 DOI: 10.1159/000014331] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We conducted a prospective randomized controlled study to confirm our earlier observation that prolonged subcutaneous implantation of peritoneal catheter reduced peritonitis rate when compared to retrospective data from patients with catheters placed by conventional access technique. A total of 60 patients were randomized into two groups: 30 patients had catheters left implanted subcutaneously for 6 weeks (I) and the other 30 patients had catheters inserted by conventional technique and had 6 weeks of break-in period (C). Subgroups of 15 patients each with new and conventional techniques used Y-connector (IY, CY) and remaining patients used standard spikes (IS, CS). Mean age was 47.7 years (range 16-71); 61.0% were male and 44.1% diabetics. Peritonitis, exit site infection, simultaneous peritonitis and exit site infection, and complication related to Staphylococcus or Pseudomonas infections were observed for up to 2 years in each patient after initiation of bag exchange or until termination of CAPD by transfer to hemodialysis or by death. Total duration of observation was 493.2 patient-months for new access technique and 409.6 patient-months for conventional technique. Patients in IY group had the lowest incidence of peritonitis (1/14.9 patient-months) and exit site infection (1/16.8 patient-months) among four subgroups. Peritonitis rate in IY was significantly lower compared to CY or CS. The total peritonitis-free period in those patients who did not experience peritonitis during the observation period was also significantly longer in IY (120 patient-months) than in CY (26 patient-months), IS (10.6 patient-months), or CS (10.4 patient-months). Simultaneous peritonitis and exit site infection was observed in none of IY group but 3 episodes in CY, 4 episodes in IS, and 3 episodes in CS. The rates of complications related to Staphylococcus aureus and Pseudomonas infections were also significantly lower in IY than in CY, IS, or CS. Technique survival did not differ between the two groups. The present results confirm our previous observation that the new access technique reduces the incidence of peritonitis probably by reducing infection via periluminal route. The Y-connector system further reduces peritonitis rate by reducing infection via intraluminal route.
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Affiliation(s)
- M S Park
- Hyonam Kidney Laboratory, Soon Chun Hyang University, Seoul, Korea
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Chung SH, Stenvinkel P, Heimbürger O, Bergström J, Lindholm B. Prevention and treatment of the malnutrition, inflammation and atherosclerosis (MIA) syndrome in uremic patients. Pol Arch Med Wewn 2000; 104:645-54. [PMID: 11392152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Affiliation(s)
- S H Chung
- Divisions of Baxter Novum and Renal Medicin, Department of Clinical Science, Karolinska Institutet, Stockholm, Sweden
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