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Park S, Shim M, Lee G, You YA, Kim SM, Hur YM, Ko H, Park MH, Na SH, Kim YH, Cho GJ, Bae JG, Lee SJ, Lee SH, Lee DK, Kim YJ. Urinary metabolite biomarkers of pregnancy complications associated with maternal exposure to particulate matter. Reprod Toxicol 2024; 124:108550. [PMID: 38280687 DOI: 10.1016/j.reprotox.2024.108550] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 01/02/2024] [Accepted: 01/23/2024] [Indexed: 01/29/2024]
Abstract
Particulate matter 2.5 (PM2.5) is associated with reproductive health and adverse pregnancy outcomes. However, studies evaluating biological markers of PM2.5 are lacking, and identifying biomarkers for estimating prenatal exposure to prevent pregnancy complications is essential. Therefore, we aimed to explore urine metabolites that are easy to measure as biomarkers of exposure. In this matched case-control study based on the PM2.5 exposure, 30 high PM2.5 group (>15 μg/m3) and 30 low PM2.5 group (<15 μg/m3) were selected from air pollution on pregnancy outcome (APPO) cohort study. We used a time-weighted average model to estimate individual PM exposure, which used indoor PM2.5 and outdoor PM2.5 concentrations by atmospheric measurement network based on residential addresses. Clinical characteristics and urine samples were collected from participants during the second trimester of pregnancy. Urine metabolites were quantitatively measured using gas chromatography-mass spectrometry following multistep chemical derivatization. Statistical analyses were conducted using SPSS version 21 and MetaboAnalyst 5.0. Small for gestational age and gestational diabetes (GDM) were significantly increased in the high PM2.5 group, respectively (P = 0.042, and 0.022). Fifteen metabolites showed significant differences between the two groups (P < 0.05). Subsequent pathway enrichment revealed that four pathways, including pentose and glucuronate interconversion with three pentose sugars (ribose, arabinose, and xylose; P < 0.05). The concentration of ribose increased preterm births (PTB) and GDM (P = 0.044 and 0.049, respectively), and the arabinose concentration showed a tendency to increase in PTB (P = 0.044). Therefore, we identified urinary pentose metabolites as biomarkers of PM2.5 and confirmed the possibility of their relationship with pregnancy complications.
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Affiliation(s)
- Sunwha Park
- Department of Obstetrics and Gynecology, College of Medicine, Ewha Medical Research Institute, Ewha Womans University, Seoul, Korea
| | - Minki Shim
- College of Pharmacy, Chung-Ang University, Seoul, Korea
| | - Gain Lee
- Graduate program in system health science and engineering, Ewha Womans University, Seoul, Korea
| | - Young-Ah You
- Department of Obstetrics and Gynecology, College of Medicine, Ewha Medical Research Institute, Ewha Womans University, Seoul, Korea
| | - Soo Min Kim
- Graduate program in system health science and engineering, Ewha Womans University, Seoul, Korea
| | - Young Min Hur
- Department of Obstetrics and Gynecology, College of Medicine, Ewha Medical Research Institute, Ewha Womans University, Seoul, Korea
| | - Hyejin Ko
- Department of Obstetrics and Gynecology, College of Medicine, Ewha Medical Research Institute, Ewha Womans University, Seoul, Korea
| | - Mi Hye Park
- Department of Obstetrics and Gynecology, Ewha Womans University Seoul Hospital, Korea
| | - Sung Hun Na
- Department of Obstetrics and Gynecology, Kangwon National University, School of Medicine, Korea
| | - Young-Han Kim
- Department of Obstetrics and Gynecology, Yonsei University College of Medicine, Korea
| | - Geum Joon Cho
- Department of Obstetrics and Gynecology, Korea University College of Medicine, Korea
| | - Jin-Gon Bae
- Department of Obstetrics and Gynecology, Keimyung University, School of Medicine, Dongsan Medical Center, Korea
| | - Soo-Jeong Lee
- Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Korea
| | | | - Dong-Kyu Lee
- College of Pharmacy, Chung-Ang University, Seoul, Korea.
| | - Young Ju Kim
- Department of Obstetrics and Gynecology, College of Medicine, Ewha Medical Research Institute, Ewha Womans University, Seoul, Korea; Graduate program in system health science and engineering, Ewha Womans University, Seoul, Korea.
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Hong SH, Lee JY, Seo S, Shin B, Jeong CH, Bae E, Kim J, Lee D, An B, Shim M, Shin JH, Lee DK, Kim YJ, Han SB. Lipidomic Analysis of Cervicovaginal Fluid for Elucidating Prognostic Biomarkers and Relevant Phospholipid and Sphingolipid Pathways in Preterm Birth. Metabolites 2023; 13:metabo13020177. [PMID: 36837795 PMCID: PMC9963162 DOI: 10.3390/metabo13020177] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/19/2023] [Accepted: 01/20/2023] [Indexed: 01/27/2023] Open
Abstract
Cervicovaginal fluid (CVF) is an excellent specimen for monitoring preterm birth (PTB) as it characterizes cervical metabolites, the vaginal environment, and specific host immune responses. However, extensive lipid analysis of CVF to explain PTB has not been studied. In this study, we performed a systematic analysis combining high-throughput lipid analysis and omics to discover the unique metabolic properties of the cervix. Liquid chromatography-high resolution mass spectrometry successfully detected a total of 190 lipids in the CVF of 30 PTB and 30 term birth (TB) pregnant women. The whole lipidomics dataset analyzed by combining multivariate and univariate statistical analysis revealed 35 lipid biomarkers, including phospholipids and sphingolipids. Remarkably, sphingomyelin, which plays a physiologically essential role in sphingolipids, was significantly downregulated in PTB. Metabolic pathway study provides a close relationship between vaginal microbial organization and cell membrane formation, further supporting the robustness of our findings. Sphingolipids and phospholipids, which were determined to be important lipids for predicting PTB in our study, showed a high value of receiver operating characteristic (ROC) curve >0.7, indicating that a lipid diagnostic test and understanding the mechanism of lipids is highly related to the vaginal microbiome. Therefore, our result has high potential as a predictor of PTB.
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Affiliation(s)
- Se Hee Hong
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Ji-Youn Lee
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Sumin Seo
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Bohyun Shin
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Cho Hee Jeong
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Eunbin Bae
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Jiyu Kim
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Donghee Lee
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Byungchan An
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Minki Shim
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Jung Hoon Shin
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Dong-Kyu Lee
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
- Correspondence: (D.-K.L.); (Y.J.K.); (S.B.H.)
| | - Young Ju Kim
- Department of Obstetrics and Gynecology, Ewha Medical Research Institute, College of Medicine, Ewha Womans University, Seoul 07984, Republic of Korea
- Correspondence: (D.-K.L.); (Y.J.K.); (S.B.H.)
| | - Sang Beom Han
- College of Pharmacy, Chung-Ang University, Seoul 06974, Republic of Korea
- Correspondence: (D.-K.L.); (Y.J.K.); (S.B.H.)
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3
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Shin B, Hong SH, Seo S, Jeong CH, Kim J, Bae E, Lee D, Shin JH, Shim M, Han SB, Lee DK. Hepatocellular Metabolic Abnormalities Induced by Long-Term Exposure to Novel Brominated Flame Retardant, Hexabromobenzene. Toxics 2023; 11:101. [PMID: 36850976 PMCID: PMC9962401 DOI: 10.3390/toxics11020101] [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] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/13/2023] [Accepted: 01/18/2023] [Indexed: 06/18/2023]
Abstract
Novel brominated flame retardants (NBFRs) are widely used to avoid environmental accumulation concerns and because of the regulations imposed on classical BFRs. However, recent studies have not revealed the negative effects of NBFR accumulation and exposure on humans. We conducted a metabolomics study on hexabromobenzene (HBB), one of the NBFRs, to investigate its effect on hepatocytes. Gas chromatography-mass spectrometry-based metabolite profiling was performed to observe metabolic perturbations by treating human livertissue-derived HepG2 cell lines with HBB for maximum 21 days. Metabolic pathway enrichment using 17 metabolite biomarkers determined via univariate and multivariate statistical analysis verified that long-term accumulation of HBB resulted in distinct diminution of eight amino acids and five other metabolites. Molecular docking of the biomarker-related enzymes revealed the potential molecular mechanism of hepatocellular response to HBB exposure, which disrupts the energy metabolism of hepatic cells. Collectively, this study may provide insights into the hidden toxicity of bioaccumulating HBB and unveil the risks associated with non-regulated NBFRs.
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Yang P, Shim M, Kang S, Kim S, Kim W, Moon J, Sung J, Kim I, Lim S, Cha D, Lip G, Joung B. Incidence of atrial fibrillation in cancer patients according to cancer type. Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.3271] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background and objectives
The prevalence of both atrial fibrillation (AF) and cancer are increasing especially in the elderly. The occurrence of AF in cancer may be related to comorbidities of patients, cancer treatment, or a direct tumor effect. The objectives of this study were to investigate the incidence of AF according to cancer type.
Methods
From the Korean National Health Insurance Service elderly (NHIS-elderly) cohort (age >60), we identified 67,077 patients with newly diagnosed cancer and without previous AF. Incidence rates of new onset AF were evaluated.
Results
The mean age of the cancer patients was 75.1 year and 53.5% were males. During a median follow-up period of 25 months, the incidence rate of AF among overall cancer patients was higher than that of age-sex matched non-cancer population (1.42 vs. 0.69 per 100 person-years, respectively). Compared with solid cancer, the risk of incident AF in patients with hematologic cancer was significantly higher (hazard ratio [HR]: 1.53, 95% confidence interval [CI]: 1.39–1.72, p<0.001). Among patients with solid cancer, thoracic (lung cancer, esophageal cancer, mediastinal cancer, etc.) and breast cancer was associated with a higher risk of AF incidence compared with other solid cancer (HR: 1.64, 95% CI: 1.53–1.76, p<0.001).
Conclusions
Cancer was associated with an increased incidence of AF. Hematologic cancer was associated with higher risk of AF incidence than solid cancer. Among solid cancer, thoracic and breast cancer was most strongly associated with the risk of AF incidence.
Funding Acknowledgement
Type of funding source: None
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Affiliation(s)
- P.S Yang
- CHA University, Seongnam, Korea (Republic of)
| | - M Shim
- CHA University, Seongnam, Korea (Republic of)
| | - S.H Kang
- CHA University, Seongnam, Korea (Republic of)
| | - S.H Kim
- CHA University, Seongnam, Korea (Republic of)
| | - W.J Kim
- CHA University, Seongnam, Korea (Republic of)
| | - J.Y Moon
- CHA University, Seongnam, Korea (Republic of)
| | - J.H Sung
- CHA University, Seongnam, Korea (Republic of)
| | - I.J Kim
- CHA University, Seongnam, Korea (Republic of)
| | - S.W Lim
- CHA University, Seongnam, Korea (Republic of)
| | - D.H Cha
- CHA University, Seongnam, Korea (Republic of)
| | - G.Y.H Lip
- University of Liverpool, Liverpool, United Kingdom
| | - B Joung
- Yonsei University College of Medicine, Cardiology, Seoul, Korea (Republic of)
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Affiliation(s)
- S Y Kye
- Cancer Information and Education Branch, National Cancer Control Institute, National Cancer Center, Goyang-si, Republic of Korea
| | - M Shim
- Department of Communication and Information, Inha University, Incheon, Republic of Korea
| | - Y C Kim
- College of Communication, Yonsei University, Seoul, Republic of Korea
| | - K Park
- Cancer Policy Branch, National Cancer Control Institute, National Cancer Center, Goyang-si, Republic of Korea
- Department of Cancer Control and Policy, National Cancer Center, Graduate School of Cancer Science and Policy, Goyang-si, Republic of Korea
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Shim M, Chung H, Cho S, Yoshida H. Disproportionation Characteristics of a Zirconium-Cobalt Hydride Bed under ITER Operating Conditions. Fusion Science and Technology 2017. [DOI: 10.13182/fst08-26] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- M. Shim
- Korea Atomic Energy Research Institute P.O. Box 305-353, 150 Deokjin-dong, Yuseong-gu, Daejeon, Korea
| | - H. Chung
- Korea Atomic Energy Research Institute P.O. Box 305-353, 150 Deokjin-dong, Yuseong-gu, Daejeon, Korea
| | - S. Cho
- Korea Atomic Energy Research Institute P.O. Box 305-353, 150 Deokjin-dong, Yuseong-gu, Daejeon, Korea
| | - H. Yoshida
- Korea Atomic Energy Research Institute P.O. Box 305-353, 150 Deokjin-dong, Yuseong-gu, Daejeon, Korea
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7
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Heo EJ, Paik ES, Shim M, Kang H, Kim WY, Kim MK, Lee YY, Choi CH, Kim TJ, Lee JW, Kim BG, Bae DS. Mature Cystic Teratoma Is a Good Indication for LESS Approach: Initial Experience of an Internal Organ Retractor (IOR) Device or Barbed Suture for LESS Cystectomy. J Minim Invasive Gynecol 2016. [DOI: 10.1016/j.jmig.2016.08.673] [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: 11/30/2022]
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8
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Paik ES, Choi HJ, Shim M, Kang H, Kim WY, Kim MK, Lee YY, Choi CH, Kim TJ, Lee JW, Kim BG, Bae DS. Comparison of Surgical Outcomes of Laparoscopy and Laparotomy for Secondary Cytoreductive Surgery with Localized Single Recurrent Site Epithelial Ovarian Cancer. J Minim Invasive Gynecol 2016. [DOI: 10.1016/j.jmig.2016.08.751] [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: 11/24/2022]
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9
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Lee H, Cho YH, Sung K, Kim WS, Shim M, Park PW, Lee YT. 166 * ROOT REPLACEMENT IN ACUTE TYPE A DISSECTION: DOES VALVE SPARING OPERATION INCREASE SURGICAL RISK? Interact Cardiovasc Thorac Surg 2014. [DOI: 10.1093/icvts/ivu276.166] [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: 11/13/2022] Open
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10
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Shim M, Chung H, Kim K, Yoshida H, Cho S, Kim D, Ahn M. Heat analysis on the initial reference design of ZrCo hydride beds for ITER. Fusion Engineering and Design 2008. [DOI: 10.1016/j.fusengdes.2008.06.035] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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11
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Malathi K, Paranjape J, Bulanova E, Shim M, Guenther-Johnson J, Faber P, Eling T, Williams B, Silverman R. A Transcriptional Signaling Pathway in the IFN System Mediated by 2′-5′-Oligoadenylate Activation of RNase L. J Urol 2006. [DOI: 10.1016/s0022-5347(05)00626-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- K. Malathi
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - J.M. Paranjape
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - E. Bulanova
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - M. Shim
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - J.M. Guenther-Johnson
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - P.W. Faber
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - T.E. Eling
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - B.R. Williams
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - R.H. Silverman
- Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio
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12
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Chow T, Hayward J, Shim M. Po-Poster - 17: GE Lightspeed-RT WideView image reconstructions: Are they suitable for radiation therapy treatment planning? Med Phys 2005. [DOI: 10.1118/1.2030996] [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: 11/07/2022] Open
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13
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Chung I, Burkart A, Szmydynger-Chodobska J, Dodd KA, Trimble WS, Miller KV, Shim M, Chodobski A. Expression of two membrane fusion proteins, synaptosome-associated protein of 25 kDa and vesicle-associated membrane protein, in choroid plexus epithelium. Neuroscience 2003; 116:349-57. [PMID: 12559091 DOI: 10.1016/s0306-4522(02)00720-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In addition to being the major site of cerebrospinal fluid formation, the choroid plexus epithelium emerges as an important source of polypeptides in the brain. Physiologically regulated release of some polypeptides synthesized by the choroid plexus has been shown. The molecular mechanisms underlying this polypeptide secretion have not been characterized, however. In the present study, synaptosome-associated protein of 25 kDa and vesicle-associated membrane protein, two membrane fusion proteins playing a critical role in exocytosis in neurons and endocrine cells, were found to be expressed in the choroid plexus epithelium. It was also shown that in choroidal epithelium, synaptosome-associated protein of 25 kDa and vesicle-associated membrane protein stably interact. Two members of the vesicle-associated membrane protein family, vesicle-associated membrane protein-1 and vesicle-associated membrane protein-2, were expressed in the rat choroid plexus at the messenger RNA and protein level. However, their newly discovered isoforms, vesicle-associated membrane protein-1b and vesicle-associated membrane protein-2b, produced by alternative RNA splicing, were not detected in choroidal tissue. Immunohistochemistry demonstrated that vesicle-associated membrane protein is confined to the cytoplasm of choroidal epithelium, whereas synaptosome-associated protein of 25 kDa is associated with plasma membranes, albeit with a varied cellular distribution among species studied. Specifically, in the rat choroid plexus, synaptosome-associated protein of 25 kDa was localized to the basolateral membrane domain of choroidal epithelium and was expressed in small groups of cells. In comparison, in ovine and human choroidal tissues, apical staining for synaptosome-associated protein of 25 kDa was found in the majority of epithelial cells. These species-related differences in cellular synaptosome-associated protein of 25 kDa distribution suggested that the synaptosome-associated protein of 25 kDa homologue, synaptosome-associated protein of 23 kDa, is also expressed in the rat choroid plexus, which was confirmed by reverse-transcriptase polymerase chain reaction. Our findings suggest that synaptosome-associated protein of 25 kDa and vesicle-associated membrane protein are involved in secretion of polypeptides from the choroid plexus epithelium. The presence of synaptosome-associated protein of 25 kDa and its homologue as well as multiple isoforms of vesicle-associated membrane protein in choroidal epithelium may play a role in the apical versus basolateral targeting of secretory vesicles.
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Affiliation(s)
- I Chung
- Department of Clinical Neurosciences, Brown University School of Medicine, Aldrich Building, Room 403, 593 Eddy Street, Providence, RI 02903, USA
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Abstract
Wurtzite ZnO nanocrystals capped with trioctylphosphine oxide or alkylamines are synthesized and characterized. These ZnO nanocrystals can be made n-type either by electron transfer doping from reducing species in solution or by above band gap photoexcitation with a UV lamp. The n-type nanocrystals exhibit a strong intraband infrared absorption, an extensive bleach of the interband band-edge absorption, and a complete quenching of the photoluminescence.
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Affiliation(s)
- M Shim
- The James Franck Institute, University of Chicago, Chicago, Illinois 60637, USA
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15
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Affiliation(s)
- M Shim
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
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16
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Abstract
Incorporating nanocrystals into future electronic or optoelectronic devices will require a means of controlling charge-injection processes and an understanding of how the injected charges affect the properties of nanocrystals. We show that the optical properties of colloidal semiconductor nanocrystal quantum dots can be tuned by an electrochemical potential. The injection of electrons into the quantum-confined states of the nanocrystal leads to an electrochromic response, including a strong, size-tunable, midinfrared absorption corresponding to an intraband transition, a bleach of the visible interband exciton transitions, and a quench of the narrow band-edge photoluminescence.
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Affiliation(s)
- C Wang
- James Franck Institute, University of Chicago, Chicago, IL 60637, USA
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17
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Abstract
Colloidal semiconductor nanocrystals combine the physical and chemical properties of molecules with the optoelectronic properties of semiconductors. Their colour is highly controllable, a direct consequence of quantum confinement on the electronic states. Such nanocrystals are a form of 'artificial atoms' (ref. 4) that may find applications in optoelectronic systems such as light-emitting diodes and photovoltaic cells, or as components of future nanoelectronic devices. The ability to control the electron occupation (especially in n-type or p-type nanocrystals) is important for tailoring the electrical and optical properties, and should lead to a wider range of practical devices. But conventional doping by introducing impurity atoms has been unsuccessful so far: impurities tend to be expelled from the small crystalline cores (as observed for magnetic impurities), and thermal ionization of the impurities (which provides free carriers) is hindered by strong confinement. Here we report the fabrication of n-type nanocrystals using an electron transfer approach commonly employed in the field of conducting organic polymers. We find that semiconductor nanocrystals prepared as colloids can be made n-type, with electrons in quantum confined states.
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Affiliation(s)
- M Shim
- James Franck Institute, University of Chicago, Illinois 60637, USA.
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18
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Abstract
Perturbations of the insulin-like growth factor (IGF) axis, including the autocrine production of IGFs, IGF binding proteins (IGFBPs) and IGFBP proteases such as prostate specific antigen (PSA), and cathepsin D have been identified in prostate, lung and breast cancer cells and tissues. Serum IGFBP-3 levels have been found to be negatively correlated to the risk of cancer. Interestingly, IGFBP-3 is a potent inhibitor of IGF action and also mediates apoptosis via an IGF-independent mechanism. Recent case-control studies have found an approximately 10% increase in the serum levels of IGF-I in patients with prostate, breast and lung cancers, which are among the most frequently diagnosed cancers. While the studies indicate an association between serum IGF-I levels and cancer risk, causality has not been established. Thus, serum IGF-I level may actually be a confounding variable, serving as a marker for autocrine tissue IGF-I production. Growth hormone (GH) therapy raises both IGF-I and IGFBP-3 levels in serum. However, the role of GH in controlling prostate, breast and lung growth and carcinogenesis remains unclear from animal studies. Increased GH levels as seen in acromegaly have been associated with benign prostatic hyperplasia but not with prostate, breast or lung cancers, although colon cancer mortality may be increased. Should serum IGF-I levels be proven to play a causal role in the pathogenesis of cancer, interpreting the risk associated with therapies such as GH replacement must take into account both the duration of exposure and the risk magnitude associated with the degree of serum IGF-I elevation. Since GH-deficient patients often have a subnormal IGF-I serum level, which normalizes on therapy, their cancer risk on GH therapy probably does not increase substantially above that of the normal population. Until further research in the area dictates otherwise, ongoing surveillance and routine monitoring of IGF-I levels in GH recipients should become standard of care.
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Affiliation(s)
- M Shim
- Division of Pediatric Endocrinology, UCLA, Los Angeles, CA 90095-1752, USA
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19
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Zhu S, Oh HS, Shim M, Sterneck E, Johnson PF, Smart RC. C/EBPbeta modulates the early events of keratinocyte differentiation involving growth arrest and keratin 1 and keratin 10 expression. Mol Cell Biol 1999; 19:7181-90. [PMID: 10490653 PMCID: PMC84711 DOI: 10.1128/mcb.19.10.7181] [Citation(s) in RCA: 125] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The epidermis is a stratified squamous epithelium composed primarily of keratinocytes that become postmitotic and undergo sequential changes in gene expression during terminal differentiation. The expression of the transcription factor CCAAT/enhancer binding protein beta (C/EBPbeta) within mouse epidermis and primary keratinocytes has recently been described; however, the function of C/EBPbeta within the epidermal keratinocyte is unknown. We report here that transient transfection of mouse primary keratinocytes with a C/EBP-responsive promoter-reporter construct resulted in a sevenfold increase in luciferase activity when keratinocytes were switched to culture conditions that induce growth arrest and differentiation. Forced expression of C/EBPbeta in BALB/MK2 keratinocytes inhibited growth, induced morphological changes consistent with a more differentiated phenotype, and upregulated two early markers of differentiation, keratin 1 (K1) and keratin 10 (K10) but had a minimal effect on the expression of late-stage markers, loricrin and involucrin. Analysis of the epidermis of C/EBPbeta-deficient mice revealed a mild epidermal hyperplasia and decreased expression of K1 and K10 but not of involucrin and loricrin. C/EBPbeta-deficient primary keratinocytes were partially resistant to calcium-induced growth arrest. Analysis of terminally differentiated spontaneously detached keratinocytes or those induced to differentiate by suspension culture revealed that C/EBPbeta-deficient keratinocytes displayed striking decreases in K1 and K10, while expression of later-stage markers was only minimally altered. Our results demonstrate that C/EBPbeta plays an important role in the early events of stratified squamous differentiation in keratinocytes involving growth arrest and K1 and K10 expression.
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Affiliation(s)
- S Zhu
- Molecular and Cellular Toxicology, Department of Toxicology, North Carolina State University, Raleigh, North Carolina 27695-7633, USA
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20
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Abstract
Laparoscopic resection of the low rectum is technically difficult. This article describes a technique for laparoscopic-assisted, transvaginal low anterior resection of the rectum, which is technically easier and leads to an excellent cosmetic result.
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Affiliation(s)
- J Kim
- Department of General Surgery, Yeungnam University Hospital, Taegu, Korea
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Benn DK, Minden NJ, Pettigrew JC, Shim M. Centralized automated quality assurance for large scale health care systems. A pilot method for some aspects of dental radiography. Oral Surg Oral Med Oral Pathol 1994; 78:247-54. [PMID: 7936597 DOI: 10.1016/0030-4220(94)90155-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
President Clinton's Health Security Act proposes the formation of large scale health plans with improved quality assurance. Dental radiography consumes 4% ($1.2 billion in 1990) of total dental expenditure yet regular systematic office quality assurance is not performed. A pilot automated method is described for assessing density of exposed film and fogging of unexposed processed film. A workstation and camera were used to input intraoral radiographs. Test images were produced from a phantom jaw with increasing exposure times. Two radiologists subjectively classified the images as too light, acceptable, or too dark. A computer program automatically classified global grey level histograms from the test images as too light, acceptable, or too dark. The program correctly classified 95% of 88 clinical films. Optical density of unexposed film in the range 0.15 to 0.52 measured by computer was reliable to better than 0.01. Further work is needed to see if comprehensive centralized automated radiographic quality assurance systems with feedback to dentists are feasible, are able to improve quality, and are significantly cheaper than conventional clerical methods.
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Affiliation(s)
- D K Benn
- Departments of Oral Diagnostic Sciences and Radiology, University of Florida Colleges of Dentistry and Medicine, Gainesville
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Shim M, Mensink N. A back care program for health care workers. Dimens Health Serv 1989; 66:24-5. [PMID: 2523327] [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: 01/01/2023]
Affiliation(s)
- M Shim
- Alberta Hospital, Edmonton
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