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Kumral ZNO, Sener G, Ozgur S, Koc M, Suleymanoglu S, Hurdag C, Yegen BC. Regular exercise alleviates renovascular hypertension-induced cardiac/endothelial dysfunction and oxidative injury in rats. J Physiol Pharmacol 2016; 67:45-55. [PMID: 27010894] [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] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 01/19/2016] [Indexed: 06/05/2023]
Abstract
The importance of physical activity in the management of renovascular diseases is well-known, but lacks evidence of underlying mechanisms. The purpose of the study was to elucidate the protective/therapeutic effects of regular exercise on experimental renovascular hypertension (RVH)-induced oxidative stress and cardiac dysfunction. Wistar albino rats underwent a RVH surgery (2K1C, Goldblatt). Three weeks later half of the rats started swimming exercise for 9 weeks (n = 15), while the sedentary RVH group (n = 15) had no exercise during that period. Sham-operated control rats (n = 10), had the similar surgical procedures but the left renal artery was left unclipped. Body weights were monitored, and blood pressures were measured weekly using tail-cuff. Echocardiographic evaluation was performed on the 3(rd) week and on the 12(th) week of the experiment before the rats were decapitated. Heart and thoracic aorta were removed and serum was collected, while aortic samples were put in a 10% formaldehyde solution for immunochemistry. Cardiac tissue samples obtained from each animal were used for the determination of tissue myeloperoxidase (MPO) and catalase (CAT) activities, malondialdehyde (MDA), and glutathione (GSH) levels. In the sedentary RVH group, aortic contractile response (contraction/relaxation in isolated organ bath), left ventricular diastolic and systolic dimensions, and immunohistochemical staining of aortic inducible nitric oxide synthase (iNOS) were increased, while ejection fraction and aortic endothelial nitric oxide synthase (eNOS) staining were decreased. RVH in the sedentary rats resulted in increased pro-inflammatory cytokines (TNF-α, IL-2, IL-6), lipid peroxidation (malondialdehyde) and neutrophil infiltration (myeloperoxidase activity) along with reductions in antioxidant glutathione and catalase levels in the cardiac tissue. Exercise after RVH increased the immunohistochemical staining of aortic eNOS, decreased iNOS staining and reversed the alterations in echocardiographic and oxidative parameters. Regular exercise commenced after RVH surgery alleviated renovascular hypertension-induced oxidative injury, by modulating oxidant-antioxidant balance via the involvement of the endothelial NO system.
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Affiliation(s)
- Z N O Kumral
- Department of Physiology, School of Medicine, Marmara University, Istanbul, Turkey
| | - G Sener
- Faculty of Pharmacy, Department of Pharmacology, Faculty of Pharmacy, Marmara University, Istanbul, Turkey
| | - S Ozgur
- Department of Biochemistry, Faculty of Dentistry, School of Medicine, Marmara University, Istanbul, Turkey
| | - M Koc
- Department of Nephrology, School of Medicine, Marmara University, Istanbul, Turkey
| | - S Suleymanoglu
- Department of Cardiology, Gulhane Military Academy, Ankara, Turkey
| | - C Hurdag
- Department of Histology and Embryology, Istanbul Bilim University, Istanbul, Turkey
| | - B C Yegen
- Department of Physiology, School of Medicine, Marmara University, Istanbul, Turkey.
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Aktas S, Sevmis S, Ozgur S, Erol C, Karakayali H. Four Separate Hepatic Vein Reconstructions in Living-Donor Right-Lobe Liver Transplantation: Case Report. Transplant Proc 2015; 47:3020-2. [PMID: 26707331 DOI: 10.1016/j.transproceed.2015.10.047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 10/20/2015] [Indexed: 10/22/2022]
Abstract
Living-donor liver transplantation (LDLT) with the use of a partial liver graft was established as an option to overcome the donor pool shortage, especially in developing countries. When right-lobe grafts are used for LDLT, appropriate venous drainage of the anterior segment is critical for maximizing the graft capacity. Here, we report a successful LDLT case using a right-lobe graft with 4 hepatic veins that were anastomosed separately to obtain adequate blood flow through the vena cava.
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Affiliation(s)
- S Aktas
- General Surgery and Transplantation, Medipol University Faculty of Medicine, Istanbul, Turkey
| | - S Sevmis
- General Surgery and Transplantation, Medipol University Faculty of Medicine, Istanbul, Turkey.
| | - S Ozgur
- Anesthesiology, Medipol University Faculty of Medicine, Istanbul, Turkey
| | - C Erol
- Radiology, Medipol University Faculty of Medicine, Istanbul, Turkey
| | - H Karakayali
- General Surgery and Transplantation, Medipol University Faculty of Medicine, Istanbul, Turkey
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Ertugrul I, Dogan V, Beken S, Ozgur S, Okumuş N, Orün UA, Karademir S. UHL'S ANOMALY AS A PART OF VACTERL ASSOCIATION. Genet Couns 2015; 26:273-276. [PMID: 26349203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
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Meckes DG, Gunawardena HP, Dekroon RM, Heaton PR, Edwards RH, Ozgur S, Griffith JD, Damania B, Raab-Traub N. Modulation of B-cell exosome proteins by gamma herpesvirus infection. Proc Natl Acad Sci U S A 2013; 110:E2925-33. [PMID: 23818640 PMCID: PMC3732930 DOI: 10.1073/pnas.1303906110] [Citation(s) in RCA: 186] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The human gamma herpesviruses, Kaposi sarcoma-associated virus (KSHV) and EBV, are associated with multiple cancers. Recent evidence suggests that EBV and possibly other viruses can manipulate the tumor microenvironment through the secretion of specific viral and cellular components into exosomes, small endocytically derived vesicles that are released from cells. Exosomes produced by EBV-infected nasopharyngeal carcinoma cells contain high levels of the viral oncogene latent membrane protein 1 and viral microRNAs that activate critical signaling pathways in recipient cells. In this study, to determine the effects of EBV and KSHV on exosome content, quantitative proteomics techniques were performed on exosomes purified from 11 B-cell lines that are uninfected, infected with EBV or with KSHV, or infected with both viruses. Using mass spectrometry, 871 proteins were identified, of which ∼360 were unique to the viral exosomes. Analysis by 2D difference gel electrophoresis and spectral counting identified multiple significant changes compared with the uninfected control cells and between viral groups. These data predict that both EBV and KSHV exosomes likely modulate cell death and survival, ribosome function, protein synthesis, and mammalian target of rapamycin signaling. Distinct viral-specific effects on exosomes suggest that KSHV exosomes would affect cellular metabolism, whereas EBV exosomes would activate cellular signaling mediated through integrins, actin, IFN, and NFκB. The changes in exosome content identified in this study suggest ways that these oncogenic viruses modulate the tumor microenvironment and may provide diagnostic markers specific for EBV and KSHV associated malignancies.
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Affiliation(s)
| | | | | | | | | | | | - Jack D. Griffith
- Lineberger Comprehensive Cancer Center
- Department of Microbiology-Immunology, University of North Carolina, Chapel Hill, NC 27599
| | - Blossom Damania
- Lineberger Comprehensive Cancer Center
- Department of Microbiology-Immunology, University of North Carolina, Chapel Hill, NC 27599
| | - Nancy Raab-Traub
- Lineberger Comprehensive Cancer Center
- Department of Microbiology-Immunology, University of North Carolina, Chapel Hill, NC 27599
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Chugh PE, Sin SH, Ozgur S, Henry DH, Menezes P, Griffith J, Eron JJ, Damania B, Dittmer DP. Systemically circulating viral and tumor-derived microRNAs in KSHV-associated malignancies. PLoS Pathog 2013; 9:e1003484. [PMID: 23874201 PMCID: PMC3715412 DOI: 10.1371/journal.ppat.1003484] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 05/24/2013] [Indexed: 02/06/2023] Open
Abstract
MicroRNAs (miRNAs) are stable, small non-coding RNAs that modulate many downstream target genes. Recently, circulating miRNAs have been detected in various body fluids and within exosomes, prompting their evaluation as candidate biomarkers of diseases, especially cancer. Kaposi's sarcoma (KS) is the most common AIDS-associated cancer and remains prevalent despite Highly Active Anti-Retroviral Therapy (HAART). KS is caused by KS-associated herpesvirus (KSHV), a gamma herpesvirus also associated with Primary Effusion Lymphoma (PEL). We sought to determine the host and viral circulating miRNAs in plasma, pleural fluid or serum from patients with the KSHV-associated malignancies KS and PEL and from two mouse models of KS. Both KSHV-encoded miRNAs and host miRNAs, including members of the miR-17–92 cluster, were detectable within patient exosomes and circulating miRNA profiles from KSHV mouse models. Further characterization revealed a subset of miRNAs that seemed to be preferentially incorporated into exosomes. Gene ontology analysis of signature exosomal miRNA targets revealed several signaling pathways that are known to be important in KSHV pathogenesis. Functional analysis of endothelial cells exposed to patient-derived exosomes demonstrated enhanced cell migration and IL-6 secretion. This suggests that exosomes derived from KSHV-associated malignancies are functional and contain a distinct subset of miRNAs. These could represent candidate biomarkers of disease and may contribute to the paracrine phenotypes that are a characteristic of KS. Circulating microRNAs (miRNAs), such as those found in exosomes, have emerged as diagnostic tools and hold promise as minimally invasive, stable biomarkers. Transfer of tumor-derived exosomal miRNAs to surrounding cells may be an important form of cellular communication. Kaposi's sarcoma-associated herpesvirus (KSHV) is the etiological agent of Kaposi's sarcoma (KS), the most common AIDS-defining cancer worldwide. Here, we survey systemically circulating miRNAs and reveal potential biomarkers for KS and Primary Effusion Lymphoma (PEL). This expands previous tissue culture studies by profiling clinical samples and by using two new mouse models of KSHV tumorigenesis. Profiling of circulating miRNAs revealed that oncogenic and viral miRNAs were present in exosomes from KS patient plasma, pleural effusions and mouse models of KS. Analysis of human oncogenic miRNAs, including the well-known miR-17-92 cluster, revealed that several miRNAs were preferentially incorporated into exosomes in our KS mouse model. Gene ontology analysis of upregulated miRNAs showed that the majority of pathways affected were known targets of KSHV signaling pathways. Transfer of these oncogenic exosomes to immortalized hTERT-HUVEC cells enhanced cell migration and IL-6 secretion. These circulating miRNAs and KS derived exosomes may therefore be part of the paracrine signaling mechanism that mediates KSHV pathogenesis.
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MESH Headings
- Animals
- Biomarkers/blood
- Biomarkers/metabolism
- Body Fluids/metabolism
- Body Fluids/virology
- Cell Line
- Cell Movement
- Cells, Cultured
- Disease Models, Animal
- Endothelial Cells/metabolism
- Endothelial Cells/virology
- Exosomes/metabolism
- Exosomes/ultrastructure
- Exosomes/virology
- Gene Expression Profiling
- Herpesvirus 8, Human/isolation & purification
- Herpesvirus 8, Human/metabolism
- Humans
- Interleukin-6/metabolism
- Mice
- MicroRNAs/blood
- MicroRNAs/metabolism
- Pleural Cavity
- Pleural Effusion, Malignant/etiology
- RNA, Neoplasm/blood
- RNA, Neoplasm/metabolism
- RNA, Viral/blood
- RNA, Viral/metabolism
- Sarcoma, Kaposi/diagnosis
- Sarcoma, Kaposi/metabolism
- Sarcoma, Kaposi/physiopathology
- Sarcoma, Kaposi/virology
- Up-Regulation
- Viral Load
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Affiliation(s)
- Pauline E. Chugh
- Lineberger Comprehensive Cancer Center, Program in Global Oncology, Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Sang-Hoon Sin
- Lineberger Comprehensive Cancer Center, Program in Global Oncology, Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Sezgin Ozgur
- Lineberger Comprehensive Cancer Center, Program in Global Oncology, Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - David H. Henry
- Department of Oncology, Joan Karnell Cancer Center, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Prema Menezes
- Department of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Jack Griffith
- Lineberger Comprehensive Cancer Center, Program in Global Oncology, Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Joseph J. Eron
- Department of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Blossom Damania
- Lineberger Comprehensive Cancer Center, Program in Global Oncology, Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Dirk P. Dittmer
- Lineberger Comprehensive Cancer Center, Program in Global Oncology, Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- * E-mail:
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Keskin M, Orun U, Dogan V, Ceylan O, Ozgur S, Kayali S, Karademir S. PP-164 CHEST PAIN WITH ST ELEVATION IN A CHILD WITH ATYPICALLY LOCALIZED HYPERTROPHIC CARDIOMYOPATHY. Int J Cardiol 2012. [DOI: 10.1016/s0167-5273(12)70367-4] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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7
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Jankowski V, Patzak A, Herget-Rosenthal S, Zidek W, Jankowski J, Jankowski V, Toelle M, van der Giet M, Zidek W, Jankowski J, Bae EH, Ma SK, Lee J, Kim SW, Jin K, Kim HJ, Vaziri ND, Osaki K, Suzuki Y, Sugaya T, Nishiyama A, Horikoshi S, Tomino Y, Matthesen SK, Gjoerup PH, Larsen T, Lauridsen TG, Nykjaer KM, Vase H, Pedersen EB, Jin K, Kim YW, Fujimori A, Yuyama H, Takakura K, Tahara A, Koakutsu A, Sanagi M, Sudoh K, Terada Y, Takakura K, Mizukami K, Miura M, Yokoyama K, Amano Y, Furukawa T, Tomura Y, Uchida W, Walkowska A, Kompanowska-Jezierska E, Sadowki J, Ozdemir ZN, Sener G, Ozgur S, Koc M, Suleymanoglu S, Yegen B, Efrati S, Berman S, Abu-Hamad R, Siman-Tov Y, Weissgarten J, Hermida RC, Ayala DE, Mojon A, Chayan L, Dominguez MJ, Fontao MJ, Alonso I, Fernandez JR, Hermida RC, Ayala DE, Mojon A, Fernandez JR, Hermida RC, Ayala DE, Fontao MJ, Mojon A, Chayan L, Dominguez MJ, Fernandez JR, Zanoli L, Alivon M, Estrugo N, Ketthab H, Pruny JF, Yanes S, Bean K, Empana JP, Jouven X, Laude RD, Laurent S, Boutouyrie P, Botticelli I, Quartagno R, Venturini M, Salvioni M, Lanzani C, Simonini M, Delli Carpini S, Zagato L, Manunta P, Blazquez-Medela AM, Garcia-Ortiz L, Gomez-Marcos MA, Recio-Rodriguez JI, Martin-Hinojal M, Rodriguez-Martin C, Castano-Sanchez C, de Cabo-Laso A, Sanchez-Salgado B, Lopez-Novoa JM, Martinez-Salgado C, Villevalde S, Tyukhmenev E, Klimenko A, Kobalava Z, Shin SJ, Oh SW, Rhee MY, Schneider M, Janka R, Raff U, Ritt M, Ott C, Uder M, Schmieder R, Ayala DE, Hermida RC, Golan E, Bernheim J, Podjarny E, Ozturk K, Bulucu F, Gezer M, Kilic S, Steele A, Rene de Cotret P, Hubert M, Leclerc JM, Tran L, Rigal R, Larsen T, Christensen FH, Bech JN, Pedersen EB, Raju B, Nirmala VR, Vijayalakshmi J, Kalaiselvi M, Rekha K, Paiva CE, Leone Aguiar AF, Coelho EB, Irzyniec T, Jez W, Paterno JC, Jara ZP, Barrinha FF, Freire AO, Casarini DE, Teixeira VDPC, Kose E, Can E, Alparslan C, Dogan A, Bal A, Demir BK, Anil M, Anil AB, Yavascan O, Aksu N, Villevalde S, Tyukhmenev E, Klimenko A, Kobalava Z, Irzyniec T, Prusek J, Szypula M, Grun O, Jeken J, Cremers B, Steimle C, Kersting S, Fliser D, Heine G, Hermida RC, Ayala DE, Fontao MJ, Mojon A, Fernandez JR, Pillar R, Lopes MGG, Cuppari L, Carvalho AB, Canziani MEF, Lipkowska K, Blumczynski A, Soltysiak J, Silska M, Poprawska A, Musielak A, Zaniew M, Zachwieja J, Labrador PJ, Gonzalez Castillo PM. Hypertension & hormones. Clin Kidney J 2011. [DOI: 10.1093/ndtplus/4.s2.45] [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: 11/14/2022] Open
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8
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Orun U, Ceylan O, Ocal B, Ozgur S, Dogan V, Yilmaz O, Keskin M, Karademir S, Senocak F. PP-192: PULMONARY BALLOON VALVULOPLASTY IN NEWBORN AND CHILDHOOD PERIOD: SHORT- AND MID-TERM RESULTS. Int J Cardiol 2011. [DOI: 10.1016/s0167-5273(11)70392-8] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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9
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Orun U, Ceylan O, Bilici M, Yilmaz O, Dogan V, Ozgur S, Keskin M, Karademir S, Ocal B, Senocak F. OP-274: ACUTE RHEUMATIC FEVER IN THE CENTRAL ANATOLIA REGION OF TURKEY: A 30 YEAR EXPERIENCE IN A SINGLE CENTER. Int J Cardiol 2011. [DOI: 10.1016/s0167-5273(11)70273-x] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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10
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Ozgur S, Senocak F, Arman Orun U, Ocal B, Karademir S, Dogan V, Yilmaz O. Ventricular non-compaction in children: clinical characteristics and course. Interact Cardiovasc Thorac Surg 2010; 12:370-3. [DOI: 10.1510/icvts.2010.246694] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Ozgur S, Damania B, Griffith J. The Kaposi's sarcoma-associated herpesvirus ORF6 DNA binding protein forms long DNA-free helical protein filaments. J Struct Biol 2010; 174:37-43. [PMID: 21047556 DOI: 10.1016/j.jsb.2010.10.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [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] [Received: 08/06/2010] [Revised: 10/20/2010] [Accepted: 10/26/2010] [Indexed: 11/18/2022]
Abstract
The Kaposi's sarcoma-associated herpesvirus ORF6 has a 41% sequence identity with Balf2 protein of Epstein-Barr virus and 23% with ICP8 protein of Herpes Simplex type I. Balf2 and ICP8 are multi-functional DNA binding proteins with roles central to viral DNA replication and recombination. In this study, we cloned the KSHV ORF6 gene, expressed the full length ORF6 protein in insect cells and purified it to homogeneity. Gel filtration revealed the protein to be present in a broad spectrum of sizes ranging from monomers to high molecular weight oligomers. Transmission electron microscopy (TEM) using negative staining under conditions favoring monomers and small oligomers revealed fields of globular particles measuring 11nm in diameter consistent with the size of a protein monomer. Incubation of ORF6 protein at room temperature for extended periods of time resulted in the bulk of the protein forming very long helical filaments. Measurements from negative staining revealed that the filaments were up to 2600nm in length, with a width of 13.7nm and a long gentle helical periodicity of 42.9nm along the filament axis. Using rapid freezing and freeze-drying, it was possible to show that the filaments consist of two protein chains wrapped around each other. The possibility that these protein filaments generate a scaffold upon which viral DNA replication, recombination, and encapsidation occur in the infected cell nucleus is discussed.
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Affiliation(s)
- Sezgin Ozgur
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599-7295, USA
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Etheridge KT, Compton SA, Barrientos KS, Ozgur S, Griffith JD, Counter CM. Tethering telomeric double- and single-stranded DNA-binding proteins inhibits telomere elongation. J Biol Chem 2008; 283:6935-41. [PMID: 18178559 DOI: 10.1074/jbc.m708711200] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mammalian telomeres are composed of G-rich repetitive double-stranded (ds) DNA with a 3' single-stranded (ss) overhang and associated proteins that together maintain chromosome end stability. Complete replication of telomeric DNA requires de novo elongation of the ssDNA by the enzyme telomerase, with telomeric proteins playing a key role in regulating telomerase-mediated telomere replication. In regards to the protein component of mammalian telomeres, TRF1 and TRF2 bind to the dsDNA of telomeres, whereas POT1 binds to the ssDNA portion. These three proteins are linked through either direct interactions or by the proteins TIN2 and TPP1. To determine the biological consequence of connecting telomeric dsDNA to ssDNA through a multiprotein assembly, we compared the effect of expressing TRF1 and POT1 in trans versus in cis in the form of a fusion of these two proteins, on telomere length in telomerase-positive cells. When expressed in trans these two proteins induced extensive telomere elongation. Fusing TRF1 to POT1 abrogated this effect, inducing mild telomere shortening, and generated looped DNA structures, as assessed by electron microscopy, consistent with the protein forming a complex with dsDNA and ssDNA. We speculate that such a protein bridge between dsDNA and ssDNA may inhibit telomerase access, promoting telomere shortening.
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Affiliation(s)
- Katherine T Etheridge
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710, USA
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13
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Sim J, Ozgur S, Lin BY, Yu JH, Broker TR, Chow LT, Griffith J. Remodeling of the human papillomavirus type 11 replication origin into discrete nucleoprotein particles and looped structures by the E2 protein. J Mol Biol 2007; 375:1165-77. [PMID: 18067922 DOI: 10.1016/j.jmb.2007.11.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2007] [Revised: 10/31/2007] [Accepted: 11/05/2007] [Indexed: 11/29/2022]
Abstract
The human papillomavirus (HPV) DNA replication origin (ori) shares a common theme with many DNA control elements in having multiple binding sites for one or more proteins spaced over several hundreds of base pairs. The HPV type 11 ori spans 103 bp and contains three palindromic E2 binding sites (E2BS-2, E2BS-3, and E2BS-4) for the dimeric E2 ori binding protein. These sites are separated by 64 and 3 bp. E2BS-1 is located 288 bp upstream of E2BS-2 and is not required for efficient transient or cell-free replication. In this study, electron microscopy was used to visualize complexes of HPV-11 DNA ori bound by purified E2 protein. DNA containing only E2BS-2 showed a single E2 dimer bound. DNA containing E2BS-3 and E2BS-4 showed two side-by-side E2 dimers, while DNA containing E2BS-2, E2BS-3, and E2BS-4 exhibited a large disk/ring-shaped protein particle bound, indicating that the DNA had been remodeled into a discrete complex, likely containing an E2 hexamer. With all four binding sites present, up to 27% of the DNA molecules were arranged into loops by E2, the majority of which spanned E2BS-1 and one of the other three sites. Studies on the dependence of looping on salt, ATP, and DTT using full-length E2 and an E2 protein containing only the carboxyl-terminal DNA binding and protein dimerization domain suggest that looping is dependent on the N-terminal domain and factors that may affect the manner in which E2 scans DNA for binding sites. The role of these structures in the modeling and regulation of the HPV-11 ori is discussed.
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Affiliation(s)
- Jeonggu Sim
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7295, USA
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14
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Ozcirpici B, Sahinoz S, Ozgur S, Bozkurt AI, Sahinoz T, Ceylan A, Ilcin E, Saka G, Acemoglu H, Palanci Y, Ak M, Akkafa F. Vaccination coverage in the South-East Anatolian Project (SEAP) region and factors influencing low coverage. Public Health 2006; 120:145-54. [PMID: 16260009 DOI: 10.1016/j.puhe.2005.04.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2004] [Revised: 01/31/2005] [Accepted: 04/06/2005] [Indexed: 11/22/2022]
Abstract
OBJECTIVES To determine the vaccination coverage of children living in the South-east Anatolian Project (SEAP) region; whether the vaccination coverage was similar to formal reports, other studies and other countries; and which factors influence vaccination, in order to indicate how vaccination coverage can be improved. STUDY DESIGN A descriptive cross-sectional study conducted in nine provinces of the SEAP region in order to determine public health problems and their causes. METHODS A population-based sample of 1150 houses was selected from rural and urban areas of the SEAP region and visited by the researchers. Questionnaires were applied in 2001 and 2002. RESULTS In the SEAP region, only 30% of children had received a complete set of vaccines. The vaccination coverage was 76.7% for Bacille Calmette-Guérin; 62.0% for the third doses of diphtheria, tetanus toxoid, pertussis and polio vaccine; 62.7% for measles; 44% for the third dose of hepatitis B vaccine in children aged 12-23 months; and 13.3% for the second dose of tetanus toxoid in women who gave birth in the last 5 years. In logistic regression analysis, residence type, number of siblings, birth interval, follow-up visits of midwives, and maternal level of education were found to influence whether children were completely vaccinated. CONCLUSIONS The findings of this study indicate that vaccination coverage is not acceptable in the SEAP region. Efforts must focus on family planning services, education of women, follow-up visits and strengthening health facilities, especially in rural regions, to improve vaccination.
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Affiliation(s)
- B Ozcirpici
- Faculty of Medicine, Department of Public Health, Gaziantep University, 27310 Gaziantep, Turkey.
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15
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Pirat A, Ozgur S, Torgay A, Candan S, Zeyneloğlu P, Arslan G. Risk factors for postoperative respiratory complications in adult liver transplant recipients. Transplant Proc 2004; 36:218-20. [PMID: 15013351 DOI: 10.1016/j.transproceed.2003.11.026] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
To determine the types and the incidence of as well as risk factors for early postoperative (<30 days) respiratory complications in adult liver transplant (LT) recipients, we reviewed The data of 44 consecutive adult LT recipients who received their grafts from January 1995 through December 2002. The data included demographic features; primary diagnosis; number of intraoperative transfusions; preoperative and postoperative laboratory values; intraoperative and postoperative characteristics; and early postoperative (<30 days) mortality. Pulmonary atelectasis, pleural effusion, pneumonia, respiratory failure, and pulmonary edema were the respiratory complications investigated. Twenty-six patients (59.1%) developed at least one respiratory complication during the early postoperative period. The most frequent complication was pleural effusion (n = 18, 40.9%), followed by atelectasis (n = 13, 29.5%), pneumonia (n = 10, 22.7%), acute respiratory failure (n = 5, 11.4%), pulmonary edema (n = 3, 6.8%), and pneumothorax (n = 2, 4.5%). Compared to the patients who did not develop these problems, the affected cohort was significantly older (27 +/- 12 years vs 36 +/- 14 years, respectively; P =.039) and required more intraoperative transfusions (P =.005). Among the overall mortality rate of 15.9%, patients who developed pneumonia showed a significantly higher mortality (40.0% vs 8.8%, respectively; P =.037). Pleural effusion, atelectasis, and pneumonia are the main respriatory complications that occur in adult LT recipients. Patient age and intraoperative transfusion requirements are important predictors of early postoperative complications. Pneumonia is associated with a poor prognosis in this patient group.
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Affiliation(s)
- A Pirat
- Başkent University, Faculty of Medicine, Department of Anesthesiology, Ankara, Turkey.
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Sancar A, Thompson C, Thresher RJ, Araujo F, Mo J, Ozgur S, Vagas E, Dawut L, Selby CP. Photolyase/cryptochrome family blue-light photoreceptors use light energy to repair DNA or set the circadian clock. Cold Spring Harb Symp Quant Biol 2003; 65:157-71. [PMID: 12760030 DOI: 10.1101/sqb.2000.65.157] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- A Sancar
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
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Abstract
Cryptochromes are blue-light photoreceptors that regulate the circadian clock in animals and growth and development in plants. Cryptochromes have high sequence homology to DNA photolyase but appear to lack photorepair activity. All previous work on cryptochromes was performed with protein expressed in heterologous systems; hence, biochemical and photochemical studies performed with these proteins were subject to certain limitations. In this study, we purified cryptochrome 2 (hCRY2) from human cells and characterized it. We find that hCRY2 exhibits fluorescence properties consistent with the presence of folate and flavin cofactors. Cryptochrome 2 binds to double-stranded DNA weakly and to single-stranded DNA with higher affinity, and this binding is further stimulated by the presence of a (6-4) photoproduct. However, light has no effect on the cryptochrome 2-(6-4) photoproduct complex. These findings reveal new properties of this protein already known to function as a circadian photoreceptor and a light-independent negative transcriptional regulator of the clock genes.
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Affiliation(s)
- Sezgin Ozgur
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
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Ozgur S. [Knowledge, attitude, and practice of family planning among women aged 15-44 in the Yildizeli district of Sivas]. Nufusbil Derg 2002; 7:95-114. [PMID: 12159461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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19
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Kahraman S, Tasdemir M, Tasdemir I, Vicdan K, Ozgur S, Polat G, Islk AZ, Biberoğlu K, Vanderzwalmen P, Nijs M, Schoysman R. Pregnancies achieved with testicular and ejaculated spermatozoa in combination with intracytoplasmic sperm injection in men with totally or initially immotile spermatozoa in the ejaculate. Hum Reprod 1996; 11:1343-6. [PMID: 8671452 DOI: 10.1093/oxfordjournals.humrep.a019384] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The efficacy of intracytoplasmic sperm injection (ICSI) employing testicular and ejaculated spermatozoa was assessed in 24 couples with totally or initially immotile spermatozoa. No criteria were employed in selecting which patients would be treated with testicular or ejaculated spermatozoa. The men were chosen at random. Testicular spermatozoa obtained by testicular sperm extraction were used in 14 and ejaculated spermatozoa were used in 10 of these couples. In all cases. asthenozoospermia was total in their basal semen sample. In 12 male partners, spermatozoa were totally immotile before and after Percoll gradient fractionation (totally immotile). In the remaining 12 men, spermatozoa initially showed a total absence of motility; however, some of the spermatozoa had showed very poor motility (0. 1%) after Percoll gradient fractionation and a 1.5-2.0 h incubation period (initially immotile). Of these 24 total asthenozoospermic males, 14 also had total teratozoospermia. The fertilization and cleavage rates in the testicular and ejaculated sperm groups were 53. 5 and 96.3 and 54.5 and 94.4% respectively. One cycle resulted in complete fertilization failure, and in 23 embryo transfer cycles a total of 10 pregnancies were obtained (41.6%). Eight pregnancies were achieved in the testicular sperm group, while only two pregnancies were obtained in the ejaculated sperm group. Four pregnancies, two from the ejaculated sperm group and two from the testicular sperm group, resulted in clinical abortions in the first trimester. Of the remaining six pregnancies, two have already resulted in healthy births and four pregnancies are now in the second or third trimester in the testicular sperm group. Using testicular spermatozoa in combination with ICSI can be an alternative mode of treatment in cases with totally or initially immotile spermatozoa in the ejaculate. Very low pregnancy rates have been obtained and no ongoing pregnancy has been achieved using ejaculated spermatozoa in these cases.
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Affiliation(s)
- S Kahraman
- Assisted Reproductive Techniques and Reproductive Endocrinology Unit, Sevgi Hospital, Ankara, Turkey
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Abstract
Deep prostatic hyperthermia (DPH) with radiofrequency waves has been found to be of considerable beneficial value in benign prostatic hyperplasia. This study was performed on 525 patients. Madsen's criteria were used for symptom scoring. All the treatments were performed at 44.5 degrees C. Mean follow-up was 18 months. DPH is well tolerated and no severe complications were noted. Statistically meaningful changes of improvement were seen in mean flow rate and residual volume in 51% of the patients.
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Ozgur S. Fertility rates in women in rural Turkey. J PAK MED ASSOC 1989; 39:72-4. [PMID: 2500543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Fertility rates in married women, aged 15-44 years, in Yildizeli, were high. Only 86% of the pregnancies resulted in normal delivery, with 50% neonatal mortality, thus reducing the population increase in the area. Similar findings are seen all over rural areas of Turkey. The mean fertility rates in women, aged 40-44 years were similar to those of eastern regions of Turkey. The abortion ratios for 1979-1981 were also identical. Poor socioeconomic conditions and unsatisfactory public health services in the region are the probable cause.
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