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Duez Q, Josse T, Lemaur V, Chirot F, Choi CM, Dubois P, Dugourd P, Cornil J, Gerbaux P, De Winter J. Correlation between the shape of the ion mobility signals and the stepwise folding process of polylactide ions. J Mass Spectrom 2017; 52:133-138. [PMID: 28112477 DOI: 10.1002/jms.3915] [Citation(s) in RCA: 10] [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] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 01/18/2017] [Accepted: 01/19/2017] [Indexed: 06/06/2023]
Abstract
In the field of polymer characterization, the use of ion mobility mass spectrometry (IMMS) remains mainly devoted to the temporal separation of cationized oligomers according to their charge states, molecular masses and macromolecular architectures in order to probe the presence of different structures. When analyzing multiply charged polymer ions by IMMS, the most striking feature is the observation of breaking points in the evolution of the average collision cross sections with the number of monomer units. Those breaking points are associated to the folding of the polymer chain around the cationizing agents. Here, we scrutinize the shape of the arrival time distribution (ATD) of polylactide ions and associate the broadening as well as the loss of symmetry of the ATD signals to the coexistence of different populations of ions attributed to the transition from opened to folded stable structures. The observation of distinct distributions reveals the absence of folded/extended structure interconversion on the ion mobility time scale (1-10 ms) and then on the lifetime of ions within the mass spectrometer at room temperature. In order to obtain information on the possible interconversion between the different observed populations upon ion activation, we performed IM-IM-MS experiments (tandem ion mobility measurements). To do so, mobility-selected ions were activated by collisions before a second mobility measurement. Interestingly, the conversion by collisional activation from a globular structure into a (partially) extended structure, i.e. the gas phase unfolding of the ions, was not observed in the energetic regime available with the used experimental setup. The absence of folded/extended interconversion, even upon collisional activation, points to the fact that the polylactide ions are 'frozen' in their specific 3D structure during the desolvation/ionization electrospray processes. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- Q Duez
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons, UMons, 23 Place du Parc, 7000, Mons, Belgium
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMons, 23 Place du Parc, 7000, Mons, Belgium
| | - T Josse
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons, UMons, 23 Place du Parc, 7000, Mons, Belgium
- Laboratory of Polymeric and Composite Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMons, 23 Place du Parc, 7000, Mons, Belgium
| | - V Lemaur
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMons, 23 Place du Parc, 7000, Mons, Belgium
| | - F Chirot
- Univ Lyon, Université Claude Bernard Lyon 1, Ens de Lyon, CNRS, Institut des Sciences Analytiques, UMR 5280, 5 rue de la Doua, F-69100, Villeurbanne, France
| | - C M Choi
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Lyon, France
| | - P Dubois
- Laboratory of Polymeric and Composite Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMons, 23 Place du Parc, 7000, Mons, Belgium
| | - P Dugourd
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Lyon, France
| | - J Cornil
- Laboratory for Chemistry of Novel Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, UMons, 23 Place du Parc, 7000, Mons, Belgium
| | - P Gerbaux
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons, UMons, 23 Place du Parc, 7000, Mons, Belgium
| | - J De Winter
- Organic Synthesis and Mass Spectrometry Laboratory, Interdisciplinary Center for Mass Spectrometry (CISMa), University of Mons, UMons, 23 Place du Parc, 7000, Mons, Belgium
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Choi CM, Yang SC, Jo HJ, Song SY, Jeon YJ, Jang TW, Kim DJ, Jang SH, Yang SH, Kim YD, Lee KH, Jang SJ, Kim YT, Kim DK, Chung DH, Kim L, Nam HS, Cho JH, Kim HJ, Ryu JS. Proteins involved in DNA damage response pathways and survival of stage I non-small-cell lung cancer patients. Ann Oncol 2012; 23:2088-2093. [PMID: 22317771 DOI: 10.1093/annonc/mdr606] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [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: 01/09/2023] Open
Abstract
BACKGROUND Biological complexity leads to significant variation in the survival of patients with stage I non-small-cell lung cancer (NSCLC). DNA damage response (DDR) pathways play a critical role in maintaining genomic stability and in the progression of NSCLC. Therefore, the development of a prognostic biomarker focusing on DDR pathways is an intriguing issue. PATIENTS AND METHODS Expression of several proteins (ATM, ATMpS1981, γH2AX, 53BP1, 53BP1pS25, Chk2, Chk2pT68, MDC1, MDC1pS964, BRCA1pS1423, and ERCC1) and overall survival were investigated in 889 pathological stage I NSCLC patients. RESULTS Low expression of BRCA1pS1423 or ERCC1 was significantly associated with worse survival in the whole cohort of patients. Analysis performed based on histology revealed that low expression of γH2AX, Chk2pT68, or ERCC1 was a poor prognostic factor in squamous cell carcinoma patients [adjusted hazard ratio (aHR), Cox P: 1.544, 0.012 for γH2AX; 1.624, 0.010 for Chk2pT68; 1.569, 0.011 for ERCC1]. The analysis of the interaction between two proteins showed that this effect was more pronounced in squamous cell carcinoma patients. However, these effects were not detected in adenocarcinoma patients. CONCLUSIONS The proteins involved in DDR pathways exhibited differential expression between squamous cell carcinoma and adenocarcinoma and were important determinants of survival in stage I squamous cell carcinoma patients.
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Affiliation(s)
- C M Choi
- Department of Pulmonary and Critical Care Medicine, Asan Medical Center, College of Medicine, University of Ulsan, Seoul
| | - S C Yang
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul
| | - H J Jo
- Department of Pathology, College of Medicine, Wonkwang University, Iksan
| | - S Y Song
- Department of Thoracic and Cardiovascular Surgery, Chonnam National University Hwasun Hospital, Hwasun-gun
| | - Y J Jeon
- Department of Internal Medicine, School of Medicine, Keimyung University, Daegu
| | - T W Jang
- Department of Internal Medicine, College of Medicine, Kosin University, Busan
| | - D J Kim
- Division of Respiratory and Allergy Medicine, Soonchunhyang University Hospital, College of Medicine, Bucheon
| | - S H Jang
- Division of Pulmonary, Allergy & Critical Care Medicine, Hallym University Sacred Heart Hospital, College of Medicine, Hallym University, Anyang
| | - S H Yang
- Department of Internal Medicine, Wonkwang University Hospital, Iksan
| | - Y D Kim
- Department of Thoracic Surgery, School of Medicine, Pusan National University, Busan
| | - K H Lee
- Department of Internal Medicine, Yeungnam University School of Medicine, Daegu
| | - S J Jang
- Department of Pathology, Asan Medical Center, College of Medicine, University of Ulsan, Seoul
| | - Y T Kim
- Department of Thoracic and Cardiovascular Surgery, Seoul National University College of Medicine, Seoul
| | - D K Kim
- Department of Thoracic and Cardiovascular Surgery, Asan Medical Center, College of Medicine, University of Ulsan, Seoul
| | - D H Chung
- Department of Pathology, Seoul National University College of Medicine, Seoul
| | | | - H S Nam
- Pulmonary Division, Department of Internal Medicine, Inha University Hospital, Incheon, Korea
| | - J H Cho
- Pulmonary Division, Department of Internal Medicine, Inha University Hospital, Incheon, Korea
| | - H J Kim
- Pulmonary Division, Department of Internal Medicine, Inha University Hospital, Incheon, Korea
| | - J S Ryu
- Pulmonary Division, Department of Internal Medicine, Inha University Hospital, Incheon, Korea.
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Abstract
Most genes function at multiple stages of metazoan development, in dividing and nondividing cells. Generating mouse conditional knock-outs (cKO), where a gene can be eliminated in a temporally and spatially controlled manner, is a valuable technique because it allows study of gene function at any stage of life. In contrast and despite the development of many other powerful genetic tools, cKO has thus far been lacking in Drosophila. We combined several recent molecular and genetic technical advances in an approach termed integrase-mediated approach for gene knock-out (IMAGO). IMAGO allows the replacement of any genomic sequence, such as a gene, with another desired sequence, including cKO alleles that can be used to create positively marked mutant cells. IMAGO should also be applicable to other genetic model organisms.
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Affiliation(s)
- Ching Man Choi
- Department of Molecular and Developmental Genetics, VIB 3000 Leuven, Belgium
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Choi CM, Kang CI, Jeung WK, Kim DH, Lee CH, Yim JJ. Role of the C-reactive protein for the diagnosis of TB among military personnel in South Korea. Int J Tuberc Lung Dis 2007; 11:233-6. [PMID: 17263297] [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: 05/13/2023] Open
Abstract
Clinicians are frequently faced with the task of differentiating between pulmonary tuberculosis (PTB) and pneumonia. We evaluated the role of the C-reactive protein test (CRP) for differentiating between TB and pneumonia among military personnel in South Korea. Only immunocompetent males were eligible. Forty-six patients with PTB and 67 with pneumonia were enrolled prospectively. Median CRP concentration was lower in patients with TB than in patients with non-tuberculous pneumonia (3.2 mg/dl [range 0.1-15.7 mg/dl] vs. 8.3 mg/dl [range 0.2-33.7 mg/dl], P < 0.001). The sensitivity and specificity for TB of a low CRP concentration (< 11.2 mg/dl) in serum was 93.3% and 40.9%, respectively. CRP concentration measurement might be useful for eliminating the diagnosis of TB.
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Affiliation(s)
- C M Choi
- Department of Internal Medicine, Armed Forces Capital Hospital, Seoul, Republic of Korea
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Srahna M, Leyssen M, Choi CM, Fradkin LG, Noordermeer JN, Hassan BA. A signaling network for patterning of neuronal connectivity in the Drosophila brain. PLoS Biol 2007; 4:e348. [PMID: 17032066 PMCID: PMC1592317 DOI: 10.1371/journal.pbio.0040348] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2005] [Accepted: 08/21/2006] [Indexed: 01/22/2023] Open
Abstract
The precise number and pattern of axonal connections generated during brain development regulates animal behavior. Therefore, understanding how developmental signals interact to regulate axonal extension and retraction to achieve precise neuronal connectivity is a fundamental goal of neurobiology. We investigated this question in the developing adult brain of Drosophila and find that it is regulated by crosstalk between Wnt, fibroblast growth factor (FGF) receptor, and Jun N-terminal kinase (JNK) signaling, but independent of neuronal activity. The Rac1 GTPase integrates a Wnt-Frizzled-Disheveled axon-stabilizing signal and a Branchless (FGF)-Breathless (FGF receptor) axon-retracting signal to modulate JNK activity. JNK activity is necessary and sufficient for axon extension, whereas the antagonistic Wnt and FGF signals act to balance the extension and retraction required for the generation of the precise wiring pattern.
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Affiliation(s)
- Mohammed Srahna
- Laboratory of Neurogenetics, Department of Molecular and Developmental Genetics, Flanders Interuniversity Institute for Biotechnology (VIB), University of Leuven School of Medicine, Leuven, Belgium
| | - Maarten Leyssen
- Laboratory of Neurogenetics, Department of Molecular and Developmental Genetics, Flanders Interuniversity Institute for Biotechnology (VIB), University of Leuven School of Medicine, Leuven, Belgium
| | - Ching Man Choi
- Laboratory of Neurogenetics, Department of Molecular and Developmental Genetics, Flanders Interuniversity Institute for Biotechnology (VIB), University of Leuven School of Medicine, Leuven, Belgium
| | - Lee G Fradkin
- Laboratory of Developmental Neurobiology, Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Jasprina N Noordermeer
- Laboratory of Developmental Neurobiology, Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Bassem A Hassan
- Laboratory of Neurogenetics, Department of Molecular and Developmental Genetics, Flanders Interuniversity Institute for Biotechnology (VIB), University of Leuven School of Medicine, Leuven, Belgium
- * To whom correspondence should be addressed. E-mail:
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Choi CM, Kang CI, Kim DH, Kim CH, Kim HJ, Lee CH, Yim JJ. The role of TST in the diagnosis of latent tuberculosis infection among military personnel in South Korea. Int J Tuberc Lung Dis 2006; 10:1342-6. [PMID: 17167950] [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: 05/13/2023] Open
Abstract
BACKGROUND The rapid and accurate diagnosis of latent tuberculosis infection (LTBI) is crucial in military settings because military personnel live in crowded circumstances and are of an age group with a high incidence of tuberculosis (TB). We tried to elucidate whether the tuberculin skin test (TST) accurately reflects the risk of TB infection among military personnel, in a setting of intermediate TB prevalence and where bacille Calmette-Guérin (BCG) vaccination is mandatory. METHODS A multi-stage cluster survey was conducted among military personnel in South Korea. Participants were grouped according to their risk of TB infection: Group 1, no identifiable risk of TB; Groups 2 and 3, recent casual (Group 2) or close (Group 3) contact with smear-positive TB patients. RESULTS Of 1045 participants, 857 (82.0%) had been BCG-vaccinated. The odds ratio (OR) of a positive TST (10 mm cut-off) for Group 2 (n = 184) and Group 3 (n = 83) compared with Group 1 (n = 778) were 0.95 (95%CI 0.67-1.38) and 1.7 (95%CI 1.06-2.70), respectively (P value for trend 0.16). CONCLUSIONS The TST does not accurately reflect the risk of LTBI among young military personnel in a setting where there is intermediate TB prevalence and extensive BCG coverage.
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Affiliation(s)
- C M Choi
- Department of Internal Medicine, Armed Forces Capital Hospital, Seoul, South Korea
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Kang CI, Choi CM, Kim DH, Kim CH, Lee DJ, Kim HB, Kim NJ, Oh MD, Choe KW. Pulmonary tuberculosis in young Korean soldiers: incidence, drug resistance and treatment outcomes. Int J Tuberc Lung Dis 2006; 10:970-4. [PMID: 16964786] [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: 05/11/2023] Open
Abstract
OBJECTIVE To determine the incidence and treatment outcomes of pulmonary tuberculosis (PTB) in young soldiers of South Korea. DESIGN From 2000 to 2004, all soldiers with a new diagnosis of tuberculosis (TB) were enrolled in the study, based on the official records of the Armed Forces Medical Command. The demographic and clinical data of the cases were evaluated retrospectively. RESULTS A total of 3115 TB cases were reported during the study period, of whom 2071 (66.5%) were reported as PTB. The annual incidence rates of PTB were 96.4 per 100,000 population in 2000, 89.3 in 2001, 67.6 in 2002, 60.2 in 2003, and 63.1 in 2004. A total of 270 patients diagnosed and treated at the Armed Forces Capital Hospital were analysed. Of the Mycobacterium tuberculosis isolates, 87.4% were susceptible to all available anti-tuberculosis drugs; 253 (93.7%) patients eventually completed initial anti-tuberculosis treatment. Among the patients with smear-positive PTB, the cure rate was 89.3% (100/112). CONCLUSION Our results demonstrate that the incidence of PTB in Korean soldiers, although still high, was declining steadily. With good case management, the overall success rate of initial treatment was approximately 90%.
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Affiliation(s)
- C I Kang
- Department of Internal Medicine, Armed Forces Capital Hospital, Seoul, Republic of Korea
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Choi CM, Yoon HI, Lee SM, Yoo CG, Kim YW, Han SK, Shim YS, Yim JJ. Oral insertion of a flexible bronchoscope is associated with less discomfort than nasal insertion for Korean patients. Int J Tuberc Lung Dis 2005; 9:344-8. [PMID: 15786902] [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: 05/02/2023] Open
Abstract
OBJECTIVE The route of bronchoscope insertion varies between centres, without a firm rationale based on well-designed studies. We therefore compared nasal and oral insertion of a flexible bronchoscope and evaluated efficacy and patient satisfaction. DESIGN Prospective randomised study of patients who underwent flexible bronchoscopy from May to September 2003 and who were randomly assigned to nasal and oral insertion approaches. RESULTS Clinical characteristics, factors related to the procedure and patient satisfaction were analysed. In total, 307 patients were randomly assigned to the nasal (n = 158) or oral insertion groups (n = 149). No difference in baseline characteristics was identified between the groups. Insertion by the oral route was associated with a smaller amount of lidocaine use during the procedure (P = 0.04) and less frequent insertion site bleeding (P = 0.005). Patients assigned to oral insertion reported less discomfort during anaesthesia (P = 0.01) and scope insertion (P < 0.001), as well as less dyspnoea (P = 0.04) and coughing (P = 0.03). CONCLUSION Oral insertion of a flexible bronchoscope was associated with less discomfort for patients than nasal insertion, although the route of insertion had no significant effect on outcome.
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Affiliation(s)
- C M Choi
- Department of Internal Medicine and Lung Institute, Division of Pulmonary and Critical Care Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
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Abstract
Leishmaniasis is a protozoan disease whose diverse clinical manifestations are dependent both on the infecting species of Leishmania and the immune response of the host. Transmission of the disease occurs by the bite of a sand fly infected with Leishmania parasites. Infection may be restricted to the skin in cutaneous leishmaniasis, limited to the mucous membranes in mucosal leishmaniasis, or spread internally in visceral leishmaniasis or kala azar. The overall prevalence of leishmaniasis is 12 million cases worldwide, and the global yearly incidence of all clinical forms approaches 2 million new cases (World Health Organization WHO/ LEISH/200.42, Leishmania/HIV Co-Infection in Southwestern Europe 1990-98: Retrospective Analysis of 965 Cases, 2000). In the last two decades, leishmaniasis, especially visceral leishmaniasis, has been recognized as an opportunistic disease in the immunocompromised, particularly in patients infected with human immunodeficiency virus.
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Affiliation(s)
- C M Choi
- Boston University School of Medicine, Massachusetts General Hospital and Harvard Medical School, USA
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Nephew KP, Choi CM, Polek TC, McBride R, Bigsby RM, Khan SA, Husseinzadeh N. Expression of fos and jun proto-oncogenes in benign versus malignant human uterine tissue. Gynecol Oncol 2000; 76:388-96. [PMID: 10684716 DOI: 10.1006/gyno.1999.5696] [Citation(s) in RCA: 13] [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: 01/13/2023]
Abstract
OBJECTIVE The objective of this study was to evaluate expression of fos and jun proto-oncogenes in benign human uterine tissue compared with malignant uterine tissue. METHODS Forty-two endometrial tissue specimens were obtained at the time of hysterectomy. Tissue samples from different phases of the menstrual cycle and from postmenopausal patients were stained using immunohistochemical methods to detect Fos and Jun proteins, estrogen and progesterone receptor status, and Ki67 (detects a nuclear antigen associated with proliferating cells). Tissue was examined microscopically for nuclear staining in endometrial epithelium and stroma. The endometrium was based on the patient's last menstrual period, pathologic dating, and proliferative versus nonproliferative status as determined by Ki67. Benign and malignant specimens were subjected to Northern blot analysis to evaluate levels of expression of c-fos, c-jun, and jun-B mRNA. The pattern of c-fos mRNA expression in malignant samples was further evaluated using in situ hybridization. RESULTS In proliferative, secretory, postmenopausal, and progesterone-influenced, uterine specimens immunohistochemically stained and examined, the endometrial and stromal nuclei stained for both Fos and Jun in varying intensities. However, no pattern was found in the variation of intensity according to the phase of the endometrium. Similarly, in malignant and benign endometrial tissue examined by Northern blot and in situ hybridization analyses, expression of proto-oncogene mRNAs was readily detectable, but no statistical correlation between type of tissue examined, grade of adenocarcinoma, and stage of endometrial cancer was found in this study. CONCLUSIONS In rodent models, control of uterine cell proliferation is related to change in expression of fos and jun proto-oncogenes. Our results indicate that hormonal control is likely to be different in human endometrium and probably involves genes other than the proto-oncogenes under study. Expression of Fos and Jun do not correlate with endometrial cancer stage and grade.
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Affiliation(s)
- K P Nephew
- Division of Gynecologic Oncology, Department of Anatomy and Cell Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267, USA
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Kang JS, Choi CM, Yun I. Effects of ethanol on lateral and rotational mobility of plasma membrane vesicles isolated from cultured mouse myeloma cell line Sp2/0-Ag14. Biochim Biophys Acta 1996; 1281:157-63. [PMID: 8664314 DOI: 10.1016/0005-2736(95)00301-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Intramolecular excimerization of Py-3-Py and fluorescence polarization of DPH were used to evaluate effects of ethanol on the rate and range of the lateral mobility and the range of the rotational mobility of bulk bilayer structures of the Sp2/0-PMV. In a concentration-dependent manner, ethanol increased the rate and range of the lateral mobility and the range of the rotational mobility of bulk bilayer structures of Sp2/0-PMV. Selective quenching of DPH by trinitrophenyl groups was utilized to examine the range of transbilayer asymmetric rotational mobility of the Sp2/0-PVM. The anisotropy (r), limiting anisotropy (r(infinity)) and order parameter (S) of DPH in the inner monolayer were 0.022, 0.029 and 0.063, respectively, greater than calculated for the outer monolayer of the Sp2/0-PMV. Selective quenching of DPH by trinitrophenyl groups was also used to examine the transbilayer asymmetric effects of ethanol on the range of the rotational mobility of the Sp2/0-PMV. Ethanol had a greater increasing effect on the range of the rotational mobility of the outer monolayer as compared to the inner monolayer of the Sp2/0-PMV. It has been proven that ethanol exhibits a selective rather than nonselective fluidizing effect within the transbilayer domains of the Sp2/0-PMV.
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Affiliation(s)
- J S Kang
- Department of Oral Biochemistry and Molecular Biology, College of Dentistry and Research Institute for Oral Biotechnology, Pusan National University, South Korea
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Mersol-Barg MS, Miller KF, Choi CM, Lee AC, Kim MH. Inhibin suppresses human chorionic gonadotropin secretion in term, but not first trimester, placenta. J Clin Endocrinol Metab 1990; 71:1294-8. [PMID: 2121772 DOI: 10.1210/jcem-71-5-1294] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Inhibin is produced by the placenta, with serum concentrations rising throughout pregnancy. In contrast, hCG serum concentrations peak in the first trimester and are 80-90% lower at term. This study was designed to determine the effect of inhibin on hCG secretion both early and late in gestation. Villus tissue from 3 term and 3 first trimester (8-10 week) placentas was maintained in an in vitro explant culture model for 5 days. Tissue from each placenta was incubated with control medium in 24 replicate wells for the first 72 h. During the final 48 h, 12 wells received control medium, and 12 wells received medium containing 1% rabbit antiserum raised against the alpha-subunit (residues 1-32) of the human inhibin peptide. The antiserum demonstrated biological activity by increasing serum FSH concentrations in an immature female rat bioassay. The relative increase in hCG secretion at the conclusion of days 4 and 5 in control and antiserum-treated groups for each first trimester and term placenta were compared to pretreatment hCG concentrations on day 3. The relative increases in hCG secretion of first trimester control groups on day 4 (mean +/- SD, 34 +/- 11%) and day 5 (63 +/- 23%) were compared to those in antiserum-treated groups on day 4 (39 +/- 13%) and day 5 (54 +/- 5%) and showed no significant difference between groups on either day. The same comparison in term cultures showed the relative increases in hCG secretion of control groups on day 4 (31 +/- 10%) and day 5 (64 +/- 50%) to be significantly lower than those in antiserum-treated groups on day 4 (100 +/- 41%) and day 5 (150 +/- 108%; P less than 0.001). These findings suggest that inhibin suppresses hCG secretion in term, but not first trimester, placentas.
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Affiliation(s)
- M S Mersol-Barg
- Department of Obstetrics and Gynecology, Ohio State University, Columbus 43210
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