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Yan H, Jin H, Xue G, Mei Q, Ding F, Hao L, Sun SH. Germline hMSH2 promoter mutation in a Chinese HNPCC kindred: evidence for dual role of LOH. Clin Genet 2007; 72:556-61. [PMID: 17894833 DOI: 10.1111/j.1399-0004.2007.00911.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Hereditary non-polyposis colorectal cancer (HNPCC) is a dominantly inherited cancer predisposition syndrome that is caused by germline mutations in mismatch repair genes. By screening the core promoters of hMSH2, hMLH1, and hMSH6 in 37 Chinese suspected HNPCC families, a novel germline mutation c.-78_-79delGT was found in the hMSH2 promoter. Its pathogenic effects were supported by the following findings: (a) it co-segregated with HNPCC-related cancers and was not present in the 220 control subjects, (b) tumors harboring the mutation lacked the expression of hMSH2 and showed high microsatellite instability, (c) it significantly decreased the promoter activity, and (d) it abolished the binding ability of the transcription factor E1A-F. Loss of heterozygosity (LOH) was found in three of the tumors studied. Intriguingly, in the tumors from patients II:1 and III:1, LOH occurred in the wild-type allele and agreed well with the traditional 'two-hit' model. In contrast, in the tumor from patient III:3, LOH occurred in the mutant allele. A pathogenic somatic mutation (c.2210+1G>A) was also found in this tumor; therefore, we proposed that the 'second hit' was inactivated by somatic mutation, and the mutant allele was lost during tumor progression; this provided evidence for the new hypothesis for the dual role of LOH.
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277
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Jin H, Zhang J, Zhang B. The effect of vibration on bed voidage behaviors in fluidized beds with large particles. BRAZILIAN JOURNAL OF CHEMICAL ENGINEERING 2007. [DOI: 10.1590/s0104-66322007000300008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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278
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Hwang SK, Jin H, Kwon JT, Chang SH, Kim TH, Cho CS, Lee KH, Young MR, Colburn NH, Beck GR, Yang HS, Cho MH. Aerosol-delivered programmed cell death 4 enhanced apoptosis, controlled cell cycle and suppressed AP-1 activity in the lungs of AP-1 luciferase reporter mice. Gene Ther 2007; 14:1353-61. [PMID: 17611588 DOI: 10.1038/sj.gt.3302983] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The long-term survival of lung cancer patients treated with conventional therapies remains poor and therefore the need for novel approaches remains high. This has led to the re-emergence of aerosol delivery as a therapeutic intervention. In this study, glucosylated polyethylenimine (GPEI) was used as carrier to investigate programmed cell death 4 (PDCD4) and PDCD4 mutant (D418A), an eIF4A-binding mutant, on PDCD4-related signaling and activator protein-1 (AP-1) activity in the lungs of AP-1 luciferase reporter mice. After confirming the efficiency of GPEI as a carrier in lungs, the effects of aerosol-delivered PDCD4 were investigated in AP-1 luciferase reporter mice. Aerosol delivery of GPEI/PDCD4 through a nose-only inhalation facilitated the apoptosis of lungs whereas aerosol PDCD4 mutant did not. Also, such aerosol delivery regulated proteins relevant to cell-cycle control and suppressed AP-1 activity. Results obtained by western blot analysis, immunohistochemistry, luciferase assay and deoxynucleotidyl-transferase-mediated nick end labeling study suggest that combined actions such as facilitating apoptosis, controlling cell cycle and suppression of AP-1 activity by PDCD4 may provide useful tool for designing lung tumor prevention and treatment by which PDCD4 functions as a transformation suppressor in the future.
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279
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Nakano H, Toyomaki Y, Ohashi S, Nakano A, Jin H, Munakata T, Akita N, Tamai K, Mitsuhashi Y. Novel COL7A1 mutations in a Japanese family with transient bullous dermolysis of the newborn associated with pseudosyndactyly. Br J Dermatol 2007; 157:179-82. [PMID: 17501948 DOI: 10.1111/j.1365-2133.2007.07955.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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280
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Lee Y, Han J, Yeom KH, Jin H, Kim VN. Drosha in primary microRNA processing. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2007; 71:51-7. [PMID: 17381280 DOI: 10.1101/sqb.2006.71.041] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
MicroRNA (miRNA)-mediated gene silencing is one of the major regulatory pathways in eukaryotes. Much effort has been made to identify the factors involved in the pathway, and our understanding of RNA silencing has significantly advanced in recent years. Our group has been working on some of the issues regarding miRNA biogenesis and, in this paper, we summarize what we and other workers in the field have learned thus far. The focus remains on the role of Drosha and DGCR8 in the early events of miRNA biogenesis in animals.
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281
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Hass R, Lueck H, von Wasielewski R, Jin H, Pich A, Kuehnle H, Grothuesmann D, Hille U, Bertram C. Altered chemotherapeutic response of primary human breast cancer epithelial cells (HBCEC) and breast cancer cell lines. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.11506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
11506 Background: A novel technique to obtain individual primary cultures of human breast cancer biopsies was filed for patent (PCT/DE 2006/000608). The different individualized HBCEC (human breast cancer epithelial cell) cultures will be characterized and chemotherapeutic effects will be compared to established breast cancer cell lines. Methods: Primary HBCEC from 20 different breast cancer patients were characterized for epithelial cell and tumor markers by immunofluorescence and PCR. Following treatment with 1μM epirubicin for 1h up to 72h differences in protein expression patterns were compared to the similarly treated MCF-7 cell line by 2D gel electrophoresis. Differentially expressed protein spots were identified by mass spectrometry and confirmed by appropriate Western blot analysis. Results: Characterization of primary HBCEC revealed continuous mitosis and cell cycle progression for more than one year in culture with no significant contamination by fibroblasts or other cell types. Whereby HBCEC underwent cell death within 72h of epirubicin treatment analysis by 2D gel and subsequent protein identification by MALDI-TOF/TOF mass spectrometry exhibited a variety of differences compared to MCF-7 cells including HSP27 and prohibitin. Appropriate Western blots confirmed these differences and revealed altered expression levels for HSP27 and prohibitin in the course of epirubicin exposure in HBCEC and MCF-7 cells, respectively, suggesting altered signalling pathways in either primary breast cancer cells or the tumor cell line. Conclusions: Individualized primary HBCEC from various patients could provide a cellular platform beyond breast cancer cell lines, which eventually meet the requirements for an appropriate breast cancer testing system including the characterization of biomarkers and the identification of potential molecular targets. No significant financial relationships to disclose.
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282
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Lock L, Khine A, Huesca M, Lawson V, Peralta R, Cammisa E, Wang M, Jin H, Lee Y, Wright J, Young A. A novel zinc-chelating small molecule exhibits cancer cell growth inhibition in vitro and in vivo by induction of tumor suppressors early growth response 1 (Egr-1) and Krüppel-Like Factor 4 (KLF4). J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.14084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
14084 Background: Lead compound LT-253 was selected from a group of 2-indolyl imidazol [4,5-d] phenanthroline derivatives with anticancer activity. It shows potent and selective anti-proliferative activity against several human cancer types in vitro, and in vivo in xenograft mouse models of human colon carcinoma (HT-29) and non-small cell lung carcinoma (H460). Methods: The mechanism of cell growth inhibition of LT-253 was investigated in HT-29 colon cancer cells using the XTT cell proliferation assay, flow cytometry and apoptosis assays. In vitro and in vivo zinc chelation was determined by competition assays using fluorescent and chromophoric chelators. Gene expression studies were performed by human genome microarray analysis and confirmed by quantitative real- time PCR. The transcription factor activity profile of LT-253-treated cells was determined by a multiplex transcription factor array and electrophoretic mobility shift assays. The functional role of specific genes was evaluated by siRNA gene knock-down. Results: LT-253 functions as chelator of zinc in vitro, and of intracellular labile zinc in HT-29 cells. Moreover, LT-253-mediated HT-29 cell growth inhibition was reversed by zinc supplementation. Gene expression profiling confirmed sustained changes in zinc-sensitive genes such as metallothionine and several zinc transporters, but not copper-sensitive or iron-sensitive genes. LT-253 induces cancer cell growth inhibition primarily through G1/S phase cell cycle arrest. Gene expression and transcription factor activities of both Egr-1 and KLF4 are induced within 4 hr post LT-253 treatment. Moreover, increased expression of both Egr-1 and KLF4 is observed in LT-253-sensitive cancer cell lines of various origins. Importantly, Egr-1 and KLF4 gene knock-down by siRNA reversed the LT-253-mediated cell growth inhibition of HT-29 cells. Conclusion: Selective chelation of intracellular labile zinc pool by LT-253 triggers immediate induction of stress-responsive tumor suppressor Egr-1 and sustained induction of zinc-responsive tumor suppressor KLF4, leading to G1/S phase cell cycle arrest and inhibition of tumor growth. No significant financial relationships to disclose.
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283
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Tucker S, Liu H, Liao Z, Wei X, Wang S, Jin H, Komaki R, Mohan R. TH-E-M100E-06: A Generalized Lyman Model Incorporating Censored Time-To-Toxicity Data and Non-Dosimetric Risk Factors. Med Phys 2007. [DOI: 10.1118/1.2761776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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284
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Jin H, Palta J, Suh T, Kim S. SU-DD-A2-05: A Generalized Dose Uncertainty Model and Its Application to Dose Verification. Med Phys 2007. [DOI: 10.1118/1.2760349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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285
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Hu B, Ullenbruch MR, Jin H, Gharaee-Kermani M, Phan SH. An essential role for CCAAT/enhancer binding protein beta in bleomycin-induced pulmonary fibrosis. J Pathol 2007; 211:455-62. [PMID: 17177178 DOI: 10.1002/path.2119] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Pulmonary fibrosis is characterized by inflammation, genesis of myofibroblasts, and abnormal tissue repair. Despite extensive research, its pathogenesis remains incompletely understood. Previously, the transcription factor CCAAT/enhancer binding protein beta (C/EBPbeta) was found to be a key regulator of myofibroblast differentiation in vitro, and to be involved in the acute phase and inflammatory responses. In an attempt to test the role of C/EBPbeta in the development of pulmonary fibrosis, experiments using C/EBPbeta null mice and their wild-type littermates were conducted. Our findings indicated that, compared to wild-type mice, animals deficient in C/EBPbeta showed significantly reduced fibrotic lesions and collagen deposition in the lung upon endotracheal injection of bleomycin. Further studies on the mechanisms by which C/EBPbeta regulates fibrosis indicated that knockout of C/EBPbeta attenuates inflammatory cytokine expression in bleomycin-treated mice. The reduced alpha-smooth muscle actin gene expression in either isolated lung fibroblasts or lung tissue from bleomycin or saline-treated C/EBPbeta deficient mice suggests that C/EBPbeta regulates myofibroblast differentiation during fibrosis. Consistent with this finding, cells from C/EBPbeta deficient mice exhibited higher proliferative rates than those from wild-type mice. These data suggest that C/EBPbeta plays an essential role in pulmonary fibrosis and that this role appears to be multifactorial with respect to cytokine expression, cell differentiation, and proliferation.
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286
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Mimura N, Hamada H, Kashio M, Jin H, Toyama Y, Kimura K, Iida M, Goto S, Saisho H, Toshimori K, Koseki H, Aoe T. Aberrant quality control in the endoplasmic reticulum impairs the biosynthesis of pulmonary surfactant in mice expressing mutant BiP. Cell Death Differ 2007; 14:1475-85. [PMID: 17464327 DOI: 10.1038/sj.cdd.4402151] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Accumulation of misfolded proteins in the endoplasmic reticulum (ER) induces the unfolded protein response (UPR), which alleviates protein overload in the secretory pathway. Although the UPR is activated under diverse pathological conditions, its physiological role during development and in adulthood has not been fully elucidated. Binding immunoglobulin protein (BiP) is an ER chaperone, which is central to ER function. We produced knock-in mice expressing a mutant BiP lacking the retrieval sequence to cause a defect in ER function without completely eliminating BiP. In embryonic fibroblasts, the UPR compensated for mutation of BiP. However, neonates expressing mutant BiP suffered respiratory failure due to impaired secretion of pulmonary surfactant by alveolar type II epithelial cells. Expression of surfactant protein (SP)-C was reduced and the lamellar body was malformed, indicating that BiP plays a critical role in the biosynthesis of pulmonary surfactant. Because pulmonary surfactant requires extensive post-translational processing in the secretory pathway, these findings suggest that in secretory cells, such as alveolar type II cells, the UPR is essential for managing the normal physiological ER protein overload that occurs during development. Moreover, failure of this adaptive mechanism may increase pulmonary susceptibility to environmental insults, such as hypoxia and ischemia, ultimately leading to neonatal respiratory failure.
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287
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Kim KJ, Moon DW, Park CJ, Simons D, Gillen G, Jin H, Kang HJ. Quantitative surface analysis of FeNi alloy films by XPS, AES and SIMS. SURF INTERFACE ANAL 2007. [DOI: 10.1002/sia.2575] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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288
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Jin H, Gong Y, Guo B, Qiu C, Liu D, Miao Z, Sun X, Tang K. Isolation and characterization of a 2C-methyl-D-erythritol 2,4-cyclodiphosphate synthase gene from Taxus media. Mol Biol 2006. [DOI: 10.1134/s0026893306060100] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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289
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Hong L, Chen Z, Zhang X, Xia L, Han Z, Lu Y, Jin H, Song J, Qiao T, Fan D. Zinc ribbon domain containing 1 protein: modulator of multidrug resistance, tumorigenesis and cell cycle. Exp Oncol 2006; 28:258-62. [PMID: 17285107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Zinc ribbon domain containing 1 (ZNRD1) gene encoding a protein consisting of two zinc ribbon domains was recently cloned from the human HLA locus. So far, ZNRD1 has been found implicated in transcription regulation and might play potential roles in mediating several biological processes, including multidrug resistance, tumorigenesis and cell cycle. This article reviewed these recent findings and provided additional information to support the role of ZNRD1 gene as a novel candidate DNA damage repair related gene.
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290
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Hu R, Jin H, Zhou S, Yang P, Li X. Proteomic analysis of hypoxia-induced responses in the syncytialization of human placental cell line BeWo. Placenta 2006; 28:399-407. [PMID: 17098281 DOI: 10.1016/j.placenta.2006.07.005] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2005] [Revised: 07/09/2006] [Accepted: 07/10/2006] [Indexed: 11/20/2022]
Abstract
Syncytiotrophoblast formation is affected by a number of pathological conditions and suppressed syncytiotrophoblast formation due to hypoxia may play a role in the pathogenesis of preeclampsia. However, the molecular basis of hypoxia-inhibited trophoblast syncytialization is poorly understood. To determine the effect of hypoxia on trophoblast syncytialization, a proteomic analysis was performed in the human cytotrophoblast cell line BeWo using two-dimensional electrophoresis and MALDI-TOF-TOF-MS. Hypoxia induced marked inhibition of BeWo cell fusion and differentiation. The proteomic profiling was established under hypoxia in BeWo cell syncytialization. The results showed that twenty proteins were significantly up-or down-regulated under hypoxia, compared with cells under normoxia. In response to hypoxia, three antioxidants, peroxiredoxin 1, peroxiredoxin 2 and 1-Cys peroxiredoxin, were down-regulated, two proteins involved in glycolysis pathway (malate dehydrogenase and enolase) were up-regulated. The expression of two members of the annexin family (annexin A2 and annexin A5) increased. We also found a decreased expression of 14-3-3 tau protein in hypoxia treated cells. Proteins implied in protein degradation and folding were also identified. The expression of two cytoskeleton components (keratin 1 and beta-actin) was found to be down-regulated. In addition, galectin-3 was up-regulated. These proteins have been implicated in regulating cellular oxidative stress, glycolysis, signal transduction, protein folding and degradation, cell mobility and cytoskeletal structure formation. Western blot analysis revealed that the levels of peroxiredoxin 1 and 14-3-3 tau decreased, whereas the levels of annexin A5 and annexin A2 increased in BeWo cells under hypoxia. These findings provided new insights into the molecular mechanisms in mediating cellular response to hypoxia in trophoblast syncytialization.
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291
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Kim S, Chung H, Jin H, Yang H, Amdur R. 2064. Int J Radiat Oncol Biol Phys 2006. [DOI: 10.1016/j.ijrobp.2006.07.467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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292
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293
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Chung H, Jin H, Suh T, Palta J, Kim S. SU-FF-J-93: Mechanical Accuracy of A Robotic Couch. Med Phys 2006. [DOI: 10.1118/1.2240869] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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294
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Su Z, Jin H, Fox C, Li H, Lynch B, Yang C, Li J, Liu C, Palta J, Kim S. TH-E-224A-02: A Systematic Analysis of Patient Specific IMRT QA Data. Med Phys 2006. [DOI: 10.1118/1.2241951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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295
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Jin H, Chung H, Suh T, Palta J, Kim S. SU-FF-T-99: Application of Dose Uncertainty Model for Plan Evaluation. Med Phys 2006. [DOI: 10.1118/1.2241024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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296
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Jin H, Min PQ. Computed tomography of gastrocolic ligament: involvement in malignant tumors of the stomach. ACTA ACUST UNITED AC 2006; 32:59-65. [PMID: 16649060 DOI: 10.1007/s00261-006-9000-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
BACKGROUND This study investigated computed tomographic (CT) features and anatomic bases of gastrocolic ligament involvement in malignant neoplasms of the stomach. METHODS We retrospectively reviewed CT scans of 34 patients known to have gastric malignant neoplasm and gastrocolic ligament involvement. Emphasis was placed on direct invasion, lymph node metastasis, and omental seeding. RESULTS CT manifestations of gastrocolic ligament involvement included direct invasion (38.2%, 13 of 34), enlargement of lymph nodes (50%, 17 of 34), "smudged" appearance (26.5%, nine of 34), "omental caking" (5.9%, two of 34), cystic mass (2.9%, one of 34), and varices of the omentum (2.9%, one of 34). We also found that gastric carcinoma and gastrointestinal stromal tumor invaded the transverse colon through the gastrocolic ligament in six patients (17.6%, six of 34). CONCLUSION CT scan is useful for detecting gastrocolic ligament involvement in gastric malignant neoplasm. The imaging features consist of a mass sign, enlargement of lymph nodes, smudged appearance, omental caking, and so on. Gastric malignant neoplasm also may involve the transverse colon through the gastrocolic ligament.
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297
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Sheikin I, Jin H, Bel R, Behnia K, Proust C, Flouquet J, Matsuda Y, Aoki D, Onuki Y. Evidence for a new magnetic field scale in CeCoIn5. PHYSICAL REVIEW LETTERS 2006; 96:077207. [PMID: 16606138 DOI: 10.1103/physrevlett.96.077207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2005] [Indexed: 05/08/2023]
Abstract
The Nernst coefficient of displays two distinct anomalies in magnetic field. The feature detected at Hk approximately 23 T is similar to what is observed in CeRu2Si2 at Hm = 7.8 T where a metamagnetic transition occurs. In CeCoIn5, new frequencies are observed in de Haas-van Alphen oscillations when the field exceeds 23 T where the Dingle temperature decreases by about 30%. Based on the Nernst coefficient anomalies, the magnetic phase diagram of CeCoIn5 is revised.
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298
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Mao SJ, Hou SX, Liang Z, Bi YQ, Wu Y, Li H, Jin H. Ion-pair reversed-phase HPLC: assay validation of sodium tanshinone IIA sulfonate in mouse plasma. J Chromatogr B Analyt Technol Biomed Life Sci 2006; 831:163-8. [PMID: 16406380 DOI: 10.1016/j.jchromb.2005.11.045] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2005] [Revised: 11/22/2005] [Accepted: 11/30/2005] [Indexed: 11/29/2022]
Abstract
Sodium tanshinone IIA sulfonate (STS), a hydrophilic ionic substance, is used as a cardiovascular drug. An ion-pair reversed-phase high-performance liquid chromatography (IP-RP-HPLC) method for the determination of STS in mouse plasma was initially developed. The assay involved a rapid and simple extraction process and subsequent detection at 271 nm. The retention time for STS was 7.5 min. Based on extracted STS standard mouse plasma at 1.5,10 and 50 microg/ml, the assay precision were 2.7, 2.1 and 1.7% with a mean accuracy of 96.7, 98.5 and 99.4%, respectively. At plasma concentration of 1.5, 50 and 75 microg/ml, the mean recovery of STS were 93.1, 96.3 and 97.5%. The limit of detection (LOD) and limit of quantification (LOQ) for STS was 0.1 microg/ml and 0.5 microg/ml, respectively. Linear responses were observed over a wide concentration range (0.5-100 microg/ml) for STS in mouse plasma. STS can be detected after intravenous administration. This method was performed for the first time in pharmacokinetic studies of STS in the mouse.
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299
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Jin H, Oh SK, Kang HJ, Lee YS, Cho MH. Temperature dependence of band alignments in ultrathin Hf–Al–O and Al2O3 films onp-Si (100). SURF INTERFACE ANAL 2006. [DOI: 10.1002/sia.2203] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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300
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Lu Y, Jin H, Chen MH, Glüer CC. Reduction of sampling bias of odds ratios for vertebral fractures using propensity scores. Osteoporos Int 2006; 17:507-20. [PMID: 16369725 DOI: 10.1007/s00198-005-0021-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2005] [Accepted: 09/30/2005] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Assessment of the predictive power of a newly introduced diagnostic technique with regard to fracture risk is frequently limited by the enormous costs and long time periods required for prospective studies. A preliminary estimate of predictive power usually relies on cross-sectional case-control studies in which bone measurements of normal and fractured subjects are compared. The measured discriminatory power is taken as an estimate of predictive power. Because of possible sample selection bias, study participants may have different bone mineral density (BMD) values, and fractured patients may have fractures of different severity levels. The same diagnostic techniques for the measured discriminatory power, expressed as odds ratios, will differ among studies with different patient and control populations. METHODS In this paper, we propose a weighted logistic regression approach to adjust the odds ratio in order to reduce the effect of sampling bias. The weight is derived from age, deformity severity, BMD, and the interactions of these, using the propensity score theory and reference population data. RESULTS Simulation examples using data from the Osteoporosis and Ultrasound Study (OPUS) demonstrate that such a procedure can effectively reduce the estimation bias of odds ratios introduced by sampling differences, such as for dual x-ray absorptiometry (DXA) scans of the spine and hip as well as various quantitative ultrasound techniques. The derived estimated odds ratios are substantially less biased, and the corresponding 95% confidence intervals contain the true odds ratios from the population data. CONCLUSIONS We conclude that a statistical correction procedure based on propensity scores and weighted logistic regression can effectively reduce the effect of sampling bias on the odds ratios calculated from cross-sectional case-control studies. For a new diagnostic technique, hip BMD and deformity severity information are necessary and likely sufficient to derive the propensity scores required to adjust the measured standardized odds ratios.
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