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Ikhlef M, Saadi S. Ophthalmic herpes zoster in an immunocompetent five-year-old child. J Fr Ophtalmol 2024; 47:103951. [PMID: 37806934 DOI: 10.1016/j.jfo.2023.03.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 03/01/2023] [Accepted: 03/01/2023] [Indexed: 10/10/2023]
Abstract
OBJECTIVE The goal of this clinical case is to report a case of ophthalmic zoster in a five-year-old boy and to insist on the relevance of early antiviral treatment (aciclovir) so as to minimize corneal affection and preserve visual function. OBSERVATION We report the case of a five-year-old boy of preschool age with no notable pathological history who came for consultation with a painful eruption affecting the forehead, the upper eyelid, the nose. The clinical examination showed many erythematous vesicles affecting the left hemi-face. The diagnosis of ophthalmic zoster has been retained. Minimum biological laboratory assessment is normal. The treatment was local antiseptic and systemic aciclovir with high dose for ten days. The evolution was favorable. Zoster is rare in children. The ophthalmic form is exceptional. The diagnosis is clinical and should mention some bladdery lesions grouped in bunches with a disposition which follows a metamere. It can be responsible for serious ocular complications. CONCLUSION The particularity of our observation is the presence of zoster in an immunocompetent child and the ophthalmic localization, that remains exceptional in children.
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Affiliation(s)
- M Ikhlef
- University of Bejaia, Targa ouzemour, Béjaïa, Algeria.
| | - S Saadi
- University of Bejaia, Targa ouzemour, Béjaïa, Algeria
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Saadi S, Aarab M, Tabyaoui I, Jouti NT. Circulating tumor cells in colorectal cancer - a review of detection methods and clinical relevance. Contemp Oncol (Pozn) 2023; 27:123-131. [PMID: 38239860 PMCID: PMC10793619 DOI: 10.5114/wo.2023.133740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 09/08/2023] [Indexed: 01/22/2024] Open
Abstract
Colorectal cancer (CRC) is the third most common cancer; it is one of the leading malignancies contributing to cancer mortality. Colorectal cancer is the third most diagnosed cancer in men and the second in women worldwide. Diagnosis of CRC depends on several clinical features such as age, primary site, tumor-node-metastasis stage, genetic parameters and the presence or absence of metastasis. The latter is a phenomenon that is induced by the shedding of tumor cells in the blood circulation by the primary tumor. Such cells are known as circulating tumor cells (CTCs). The detection of CTCs is quite challenging due to their scarceness; thus it requires their enrichment and characterization. Studying the utility of CTCs in the diagnosis of CRC has been the aim of several studies; they demonstrated that ≥ 3 CTCs in 7.5 ml of blood is correlated with a worse prognosis and short progression-free and overall survival. Circulating tumor cells have also been monitored to study treatment response and predict future relapses. The present review aims to bring to light the different techniques used to detect and characterize these malignant cells in the peripheral blood of cancer patients as well as the clinical relevance of CTCs in CRC patients.
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Affiliation(s)
- Salma Saadi
- Laboratory of Cellular and Molecular Inflammatory, Degenerative and Oncologic Pathophysiology – Faculty of Medicine and Pharmacy of Casablanca Hassan II University, Casablanca, Morocco
| | - Meryem Aarab
- Laboratory of Cellular and Molecular Inflammatory, Degenerative and Oncologic Pathophysiology – Faculty of Medicine and Pharmacy of Casablanca Hassan II University, Casablanca, Morocco
| | - Imane Tabyaoui
- Laboratory of Cellular and Molecular Inflammatory, Degenerative and Oncologic Pathophysiology – Faculty of Medicine and Pharmacy of Casablanca Hassan II University, Casablanca, Morocco
| | - Nadia Tahiri Jouti
- Laboratory of Cellular and Molecular Inflammatory, Degenerative and Oncologic Pathophysiology – Faculty of Medicine and Pharmacy of Casablanca Hassan II University, Casablanca, Morocco
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Aarab M, Saadi S, Tabyaoui I, Badre L, Jouti NT. An improved method for paraffin-embedded cytological preparations: application to the detection of circulating tumour cells. Contemp Oncol (Pozn) 2023; 27:35-40. [PMID: 37266337 PMCID: PMC10230238 DOI: 10.5114/wo.2023.127190] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 04/24/2023] [Indexed: 06/03/2023] Open
Abstract
Introduction Conventional tissue biopsy is a key examination in cancer diagnosis. However, liquid biopsy is an alternative and less invasive solution that allows the detection of circulating tumour cells (CTCs). CTCs have emerged as a potential screening, diagnostic, and prognostic tool in cancer management. There are many technologies available for the detection and characterization of these cells, but most are either expensive or complicated to apply routinely. Cytological cell blocks (cytoblocks) may be a more practical and cost-effective method to enrich and characterize CTCs and even perform molecular studies. These cytoblocks allow the processing, analysis, and storage of cell suspensions and fluid aspiration samples containing CTCs. Material and methods Here we detail a manual protocol based on isolation by density gradient centrifugation, formalin fixing, and paraffin embedding as well as morphological identification for cytological analysis and phenotyping by immunocytochemistry. This method is the result of technical adjustments of previously established protocols. Results We succeeded in modifying a protocol for the construction of cytoblocks and applied it to study CTCs in lung and colorectal cancers, respectively. Conclusion This less expensive protocol offers a possibility for use in routine diagnosis and can be applied in other fields of research, such as hematology for hematological malignancies and immunology.
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Affiliation(s)
| | | | | | | | - Nadia Tahiri Jouti
- Address for correspondence Prof. Nadia Tahiri Jouti, PhD Laboratory of Cellular and Molecular Inflammatory Degenerative and Oncologic Pathophysiology Faculty of Medicine and Pharmacy Hassan II University Casablanca, Morocco e-mails: ,
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Saadi S, Masmoudi T, Ben Daly A, Jedidi M, Mokni M, Ben Dhiab M, Zemni M, Souguir MK. Pulmonary alveolar capillary dysplasia in infants: A rare and deadly missed diagnosis. Ann Cardiol Angeiol (Paris) 2020; 71:112-114. [PMID: 32829892 DOI: 10.1016/j.ancard.2020.07.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Accepted: 07/21/2020] [Indexed: 10/23/2022]
Abstract
The pulmonary alveolocapillary dysplasia (ACD) with pulmonary vein misalignment (PVM) is a rare condition characterized by a congenital anomaly of the development of the pulmonary parenchyma. We present a case of an 8-month-old infant who died quickly from acute respiratory failure complicating an unknown ACD. We also describe its epidemiological characteristics in infants and we discuss the diagnosis's difficulties. In this case, a pulmonary arterial hypertension was decompensated by an infection. A medico-legal autopsy was performed. As for the Histological examination, it showed the features of ACD/PVM.
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Affiliation(s)
- S Saadi
- Department of Forensic Medicine, Farhat Hached University Hospital, 4000, Sousse, Tunisia; Faculty of Medicine, University of Sousse, 4000, Sousse, Tunisia.
| | - T Masmoudi
- Department of Forensic Medicine, Farhat Hached University Hospital, 4000, Sousse, Tunisia; Faculty of Medicine, University of Sousse, 4000, Sousse, Tunisia
| | - A Ben Daly
- Department of Forensic Medicine, Farhat Hached University Hospital, 4000, Sousse, Tunisia; Faculty of Medicine, University of Sousse, 4000, Sousse, Tunisia
| | - M Jedidi
- Department of Forensic Medicine, Farhat Hached University Hospital, 4000, Sousse, Tunisia; Faculty of Medicine, University of Sousse, 4000, Sousse, Tunisia
| | - M Mokni
- Department of Pathology, Farhat Hached University Hospital, 4000, Sousse, Tunisia; Faculty of Medicine, University of Sousse, 4000, Sousse, Tunisia
| | - M Ben Dhiab
- Department of Forensic Medicine, Farhat Hached University Hospital, 4000, Sousse, Tunisia; Faculty of Medicine, University of Sousse, 4000, Sousse, Tunisia
| | - M Zemni
- Department of Forensic Medicine, Farhat Hached University Hospital, 4000, Sousse, Tunisia; Faculty of Medicine, University of Sousse, 4000, Sousse, Tunisia
| | - M K Souguir
- Department of Forensic Medicine, Farhat Hached University Hospital, 4000, Sousse, Tunisia; Faculty of Medicine, University of Sousse, 4000, Sousse, Tunisia
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Belhadj M, Saadi S, Ben Jomaa S, Dhouieb R, Kort I, Marzougui M, Amine Mesrati M, Chadly A, Haj Salem N. [Death due to myocardial infarction in young patients: A study of 312 cases of sudden death]. Ann Cardiol Angeiol (Paris) 2020; 69:67-73. [PMID: 32222285 DOI: 10.1016/j.ancard.2020.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 03/04/2020] [Indexed: 06/10/2023]
Abstract
Sudden cardiac death in young is seen as a dramatic phenomenon requiring knowledge of its impact. We aim to study the epidemiological characteristics of sudden cardiac ischemic death in young, and to discuss his involvement in the occurrence of death. We performed a retrospective cohort study using autopsy data from the department of forensic medicine of the University Hospital of Fattouma Bourguiba, Monastir-Tunisia. A review of all autopsies performed during 23 years was done. In each case, clinical information and circumstances of death were obtained. We have included all sudden death in persons aged between 1 year and 35 years for the male and from one year to 45 years for female. We collected 312 cases of sudden death during the studied period. The collected data were processed using SPSS 20. The significance level was set at 0.05. Thirty-two cases of cardiac ischemic sudden death have been collected. Myocardial infarction was the second cause of sudden death in young patients. There was a male predominance. The most affected subjects were aged between 25-45 years. The death occurred more frequently at rest. Coronary artery disease has been discovered in twenty-four cases (75%). The myocardial infarction occurred on healthy coronary arteries in eight cases. An anomalous course of coronary arteries, in particular myocardial bridging, was found in eight cases (25%). Toxicological screening was negative in all cases. Identifying epidemiological characteristics of sudden cardiac ischemic death in this population is important for guiding approaches to prevention that must be based on dietary hygienic measures and the control of cardiovascular risk factors.
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Affiliation(s)
- M Belhadj
- Service de médecine légale, université de Monastir, hôpital universitaire Fattouma Bourguiba, Monastir, Tunisie
| | - S Saadi
- Service de médecine légale, université de Monastir, hôpital universitaire Fattouma Bourguiba, Monastir, Tunisie
| | - S Ben Jomaa
- Service de médecine légale, université de Monastir, hôpital universitaire Fattouma Bourguiba, Monastir, Tunisie
| | - R Dhouieb
- Service de médecine légale, université de Monastir, hôpital universitaire Fattouma Bourguiba, Monastir, Tunisie
| | - I Kort
- Service de médecine légale, université de Monastir, hôpital universitaire Fattouma Bourguiba, Monastir, Tunisie
| | - M Marzougui
- Service de médecine légale, université de Monastir, hôpital universitaire Fattouma Bourguiba, Monastir, Tunisie
| | - M Amine Mesrati
- Service de médecine légale, hôpital Taher Sfar Mahdia, Mahdia, Tunisie
| | - A Chadly
- Service de médecine légale, université de Monastir, hôpital universitaire Fattouma Bourguiba, Monastir, Tunisie
| | - N Haj Salem
- Service de médecine légale, université de Monastir, hôpital universitaire Fattouma Bourguiba, Monastir, Tunisie.
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Amri K, Chefi MA, Znagui T, Rafrafi A, Saadi S, Nouisri L. Resurfacing shoulder hemi arthroplasty in ballistic injuries. A case report. Int J Surg Case Rep 2019; 65:48-51. [PMID: 31689627 PMCID: PMC6838807 DOI: 10.1016/j.ijscr.2019.10.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2019] [Revised: 10/07/2019] [Accepted: 10/14/2019] [Indexed: 11/29/2022] Open
Abstract
Ballistic tramatology in the upper humerus extremity region presents challenging management difficulties. Resurfacing shoulder hemi arthroplasty in ballistic injuries is not commonly reported. The indication of resurfacing shoulder hemi arthroplasty was appropriate regarding good functional outcome.
Introduction Ballistic traumatology of the shoulder joint is uncommon. Usually, it is associated to comminuted fractures of the upper humerus. Total shoulder arthroplasty has been proposed to restore a good function. The indication of resurfacing hemi arthroplasty still controversial and is not commonly reported after ballistic traumatology. Presentation of case We report the case of a 26-year-old soldier victim of a gunshot of the left shoulder entailing a comminuted complex fracture of the upper extremity of the humerus. After shoulder immobilization of 3 months joint mobility was very limited. Radiographs showed bone malunion with a total loss of the hemispherical form of the humeral head. Patient has undergone a resurfacing hemi arthroplasty. Surgery outcome was good. At five years of follow-up, there were no major functional complaints. Clinical and radiological result was satisfactory with a good shoulder mobility. Discussion Shoulder arthroplasty provided good functional outcome in case of post fracture sequelae. Difficulty was to choose between total arthroplasty and hemi arthroplasty. In young and active patients, authors disapproved total arthroplasty in post traumatic gleno-humeral arthrosis to prevent revision difficulties especially after glenoid erosion. Conclusion Although follow-up still be limited, the indication of shoulder hemi arthroplasty was appropriate regarding functional outcome and patient satisfaction. Further clinical and radiological supervision still necessary to detect glenoid erosion.
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Affiliation(s)
- K Amri
- Military Hospital of Instruction of Tunis, Tunisia
| | - M A Chefi
- University of Tunis El Manar, Faculty of Medicine of Tunis, Tunisia.
| | - T Znagui
- Military Hospital of Instruction of Tunis, Tunisia
| | - A Rafrafi
- Military Hospital of Instruction of Tunis, Tunisia
| | - S Saadi
- Military Hospital of Instruction of Tunis, Tunisia
| | - L Nouisri
- Military Hospital of Instruction of Tunis, Tunisia
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Koletzko B, Jochum F, Saadi S, Stajer K, Wagner K, Zylajew W, Claßen M. Untergewicht und Mangelernährung bei pädiatrischen Patienten. Monatsschr Kinderheilkd 2018. [DOI: 10.1007/s00112-018-0475-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Gourine M, Mostefa-Kara A, Saadi S, Arrar M, Cherrak A. Central pontine myelinolysis in a type 1 diabetes patient with chronic hepatitis. Rev Neurol (Paris) 2018; 174:66-67. [PMID: 28583270 DOI: 10.1016/j.neurol.2017.05.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Revised: 03/18/2017] [Accepted: 05/15/2017] [Indexed: 10/19/2022]
Affiliation(s)
- M Gourine
- Department of internal medicine, university hospital and medical school of Oran, centre hospitalier universitaire d'Oran, 76, boulevard du Dr-Benzerdjeb, 31000 Oran, Algeria.
| | - A Mostefa-Kara
- Department of radiology, university hospital of Oran, Algeria
| | - S Saadi
- Department of internal medicine, university hospital and medical school of Oran, centre hospitalier universitaire d'Oran, 76, boulevard du Dr-Benzerdjeb, 31000 Oran, Algeria
| | - M Arrar
- Department of internal medicine, university hospital and medical school of Oran, centre hospitalier universitaire d'Oran, 76, boulevard du Dr-Benzerdjeb, 31000 Oran, Algeria
| | - A Cherrak
- Department of internal medicine, university hospital and medical school of Oran, centre hospitalier universitaire d'Oran, 76, boulevard du Dr-Benzerdjeb, 31000 Oran, Algeria
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Gourine M, Saadi S, Arrar M, Cherrak A. Morphée révélée par des accès douloureux abdominaux : à propos d’un cas. Rev Med Interne 2016. [DOI: 10.1016/j.revmed.2016.10.350] [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: 11/29/2022]
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Saadi S, Kharoubi O, Bennaama N, Kazouz H, Aoues A, Slimani M. Lead Induced Oxidative Stress and Development Change on Coriandrum sativum. ACTA ACUST UNITED AC 2016. [DOI: 10.9734/ijpss/2016/18589] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Brah S, Thomas G, Chapon F, Brescianini A, Lanfranchi MA, Saadi S, Harle JR, Durand JM, Jean R, Chiche L. Vascularité cérébrale lupique : à propos d’un cas révélé par hémorragie cérébro-méningée sur rupture d’anévrisme inaugurale. Rev Med Interne 2010. [DOI: 10.1016/j.revmed.2010.10.224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Saadi S, Ariffin A, Ghazali H, Miskandar M, Abdulkarim S, Boo H. Effect of Blending and Emulsification on Thermal Behavior, Solid Fat Content, and Microstructure Properties of Palm Oil-Based Margarine Fats. J Food Sci 2010; 76:C21-30. [DOI: 10.1111/j.1750-3841.2010.01922.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Saadi S, Chiche L, Brah S, Lanfranchi MA, Thomas G, Gouriou E, Jean R, Harle JR, Durand JM. Anémie hémolytique par favisme se révélant seulement à l’âge adulte et chez la femme : à propose de deux cas. Rev Med Interne 2010. [DOI: 10.1016/j.revmed.2010.10.303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Hummelshøj JS, Landis DD, Voss J, Jiang T, Tekin A, Bork N, Dułak M, Mortensen JJ, Adamska L, Andersin J, Baran JD, Barmparis GD, Bell F, Bezanilla AL, Bjork J, Björketun ME, Bleken F, Buchter F, Bürkle M, Burton PD, Buus BB, Calborean A, Calle-Vallejo F, Casolo S, Chandler BD, Chi DH, Czekaj I, Datta S, Datye A, DeLaRiva A, Despoja V, Dobrin S, Engelund M, Ferrighi L, Frondelius P, Fu Q, Fuentes A, Fürst J, García-Fuente A, Gavnholt J, Goeke R, Gudmundsdottir S, Hammond KD, Hansen HA, Hibbitts D, Hobi E, Howalt JG, Hruby SL, Huth A, Isaeva L, Jelic J, Jensen IJT, Kacprzak KA, Kelkkanen A, Kelsey D, Kesanakurthi DS, Kleis J, Klüpfel PJ, Konstantinov I, Korytar R, Koskinen P, Krishna C, Kunkes E, Larsen AH, Lastra JMG, Lin H, Lopez-Acevedo O, Mantega M, Martínez JI, Mesa IN, Mowbray DJ, Mýrdal JSG, Natanzon Y, Nistor A, Olsen T, Park H, Pedroza LS, Petzold V, Plaisance C, Rasmussen JA, Ren H, Rizzi M, Ronco AS, Rostgaard C, Saadi S, Salguero LA, Santos EJG, Schoenhalz AL, Shen J, Smedemand M, Stausholm-Møller OJ, Stibius M, Strange M, Su HB, Temel B, Toftelund A, Tripkovic V, Vanin M, Viswanathan V, Vojvodic A, Wang S, Wellendorff J, Thygesen KS, Rossmeisl J, Bligaard T, Jacobsen KW, Nørskov JK, Vegge T. Density functional theory based screening of ternary alkali-transition metal borohydrides: A computational material design project. J Chem Phys 2009; 131:014101. [DOI: 10.1063/1.3148892] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [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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Tahir N, Abdelssadek Z, Halliche D, Saadi S, Chebout R, Cherifi O, Bachari K. Mg-Fe-hydrotalcite as catalyst for the benzylation of benzene and other aromatics by benzyl chloride reactions. SURF INTERFACE ANAL 2008. [DOI: 10.1002/sia.2695] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Bahl CRH, Hansen MF, Pedersen T, Saadi S, Nielsen KH, Lebech B, Mørup S. The magnetic moment of NiO nanoparticles determined by Mössbauer spectroscopy. J Phys Condens Matter 2006; 18:4161-4175. [PMID: 21690771 DOI: 10.1088/0953-8984/18/17/005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We have studied the magnetic properties of (57)Fe-doped NiO nanoparticles using Mössbauer spectroscopy and magnetization measurements. Two samples with different degrees of interparticle interaction were studied. In both samples the particles were characterized by high-resolution transmission electron microscopy and x-ray diffraction and found to be plate-shaped. Computer simulations showed that high-field Mössbauer data are very sensitive to the size of the uncompensated magnetic moment. From analyses of the Mössbauer spectra we have estimated that the size of the uncompensated magnetic moment is in accordance with a model based on random occupation of surface sites. The analyses of the magnetization data gave larger magnetic moments, but the difference can be explained by the different sensitivity of the two methods to a particle size distribution and by interactions between the particles, which may have a strong influence on the moments estimated from magnetization data.
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Affiliation(s)
- C R H Bahl
- Department of Physics, Building 307, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark. Materials Research Department, Building 227, Risø National Laboratory, DK-4000 Roskilde, Denmark
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Abstract
BACKGROUND Platelets exert their normal functions at sites of endothelial disruption by plugging discontinuities in blood vessels and secreting products that promote thrombosis, inflammation, and the healing of wounds. Whether platelets might induce these changes in xenograft blood vessels, leading to development of acute vascular rejection, has been uncertain. METHODS To examine the role of human platelets in modulation of xenograft endothelium, pig endothelial cells were treated with human platelets. RESULTS Treatment of quiescent porcine endothelial cells with human platelets modulated the endothelial cells. Whereas resting human platelets caused little change in normal porcine endothelial cells, platelets activated with small amounts of thrombin induced striking changes in the endothelial cells, including the induction of tissue factor activity, the expression of E-selectin, and the secretion of endothelin-1. These changes were induced, at least in part, by interleukin-1 (IL-1) associated with the platelet surface and were modified by the secretion of transforming growth factor-beta (TGF-beta). CONCLUSION These findings may explain how the activation of platelets at an early point in the rejection of vascularized organ xenografts or in chronic diseases might contribute to thrombotic, ischemic, and inflammatory changes characteristic of an organ xenograft undergoing rejection.
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Affiliation(s)
- M Bustos
- Department of Surgery, Universidad de Bavarra, Pamplona, Spain
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Nagayasu T, Saadi S, Holzknecht RA, Miyata Y, Plummer TB, Platt JL. Expression of tissue factor and tissue factor pathway inhibitor in porcine endothelium in response to natural antibody and complement. Transplant Proc 2001; 33:788. [PMID: 11267072 DOI: 10.1016/s0041-1345(00)02255-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- T Nagayasu
- Transplantation Biology, and the Department of Surgery, Immunology and Pediatrics Mayo Clinic, Rochester, Minnesota, USA
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Nagayasu T, Saadi S, Holzknecht RA, Plummer TB, Platt JL. Induction of tissue factor mRNA in acute vascular rejection: localization by in situ reverse transcriptase polymerase chain reaction. Transplant Proc 2000; 32:970. [PMID: 10936302 DOI: 10.1016/s0041-1345(00)01066-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- T Nagayasu
- Departments of Surgery, Immunology and Pediatrics, Mayo Clinic, Rochester, Minnesota 55905, USA
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Abstract
BACKGROUND Interaction of complement with endothelial cells (ECs) underlies the development of inflammation and coagulation in disease. Assembly of the membrane attack complex (MAC) of complement on EC membrane, like stimulation with cytokines, upregulates tissue factor and cyclooxygenase-2 but does so via the intermediary action of IL-1alpha. We asked whether the MAC activates porcine aortic and microvascular ECs in a global manner by this mechanism and whether this mechanism is used by membrane pore-forming structures. METHODS AND RESULTS Exposure of ECs to complement caused upregulation of mRNAs for E-selectin, intracellular adhesion molecule-1, vascular cell adhesion molecule-1, Ikappa-Balpha, interleukin (IL)-1alpha, IL-1beta, IL-8, and plasminogen activator inhibitor-1 over a period of 6 hours. The expression of these genes was not a primary response to stimulation, however, because IL-1 receptor antagonist inhibited expression of these genes. Activation of ECs by complement depended on the autocrine action of IL-1alpha, because complement-mediated EC activation was inhibited by anti-IL-1alpha antibodies. Melittin and mastoparan, amphiphilic pore-forming peptides like the MAC, induced E-selectin through intermediary action of IL-1. CONCLUSIONS These findings suggest that transmembrane pore-forming proteins, as a class of molecules, activate ECs through the autocrine effects of IL-1alpha.
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Affiliation(s)
- S Saadi
- Department of Surgery, Mayo Clinic, Rochester, MN 55905, USA.
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Rebhandl W, Felberbauer FX, Huber WD, Puig S, Paya K, Rauhofer U, Saadi S, Aberle J, Horcher E. [Progressive familial intrahepatic cholestasis (Byler disease): current genetics and therapy]. Klin Padiatr 2000; 212:64-70. [PMID: 10812555 DOI: 10.1055/s-2000-9654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Progressive familial intrahepatic cholestasis (PFIC) is a congenital liver disease. First symptoms can frequently be seen shortly after birth. Quality and expectation of life are substantially reduced due to severe pruritus and the complications of progressive liver cirrhosis. PFIC is diagnosed on the basis of characteristic clinical and laboratory parameters and genetic analysis after exclusion of other liver diseases leading to intrahepatic cholestasis. Medical therapy is only effective in a proportion of children with PFIC. Partial biliary diversion (PBD) is nowadays considered the therapy of choice in patients with therapy-refractive pruritus. If performed in time, damage to the liver can be delayed or arrested, thus orthotopic liver transplantation (OLT) can be postponed or even avoided in at least some patients with PFIC. Besides providing a current overview of PFIC, we report on three patients who were successfully treated surgically. One patient was subjected to a new technique of PBD (cholecysto-appendicostomy), the other two had OLT.
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Affiliation(s)
- W Rebhandl
- Abteilungen für Kinderchirurgie, Medizinischen Fakultät der Universität Wien. at
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23
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Nagayasu T, Saadi S, Holzknecht RA, Plummer TB, Platt JL. Expression of tissue factor mRNA in cardiac xenografts: clues to the pathogenesis of acute vascular rejection. Transplantation 2000; 69:475-82. [PMID: 10708098 DOI: 10.1097/00007890-200002270-00003] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Acute vascular rejection destroys vascularized xenografts over a period of hours to days and is now considered the major hurdle to the clinical application of xenotransplantation. The hallmark of acute vascular rejection is diffuse intravascular coagulation; however, the pathogenesis of coagulation is a matter of controversy. One line of evidence points to activated endothelial cells and another to activated inflammatory cells as a source of tissue factor and thus as a primary cause of this lesion. The distinction between the two mechanisms inducing coagulation in the xenograft provides an opportunity for specific intervention. METHODS To explore these mechanisms, we studied the expression of tissue factor mRNA by in situ reverse transcriptase-polymerase chain reaction in relation to the histopathologic manifestations of acute vascular rejection in guinea pig hearts transplanted into rats treated by cobra venom factor to avoid the hyperacute rejection. RESULTS Three hours after transplantation and before the deposition of fibrin, tissue factor mRNA was expressed in the endothelial cells lining small and medium blood vessels and in smooth muscle cells of guinea pig cardiac xenografts. Sixteen hours after transplantation, while rat tissue factor mRNA was expressed only in occasional infiltrating cells, cardiac xenografts showed prominent deposits of fibrin in small vessels. Maximum expression of tissue factor on rat infiltrating cells was observed 48 hr after transplantation. CONCLUSIONS These results suggest that in acute vascular rejection, coagulation is initiated on the donor vascular system, while the procoagulant characteristics of infiltrating cells may reflect a response to tissue injury rather than a cause.
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Affiliation(s)
- T Nagayasu
- Transplantation Biology, Department of Surgery, Mayo Clinic, Rochester, Minnesota 55905, USA
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24
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Abstract
1. Xenotransplantation, or transplantation across species, leads to rejection, which destroys the xenograft within hours to days of transplantation. 2. Complement is a major barrier to xenotransplantation of vascularized organs and is believed to play an important role in the rejection process. 3. The present paper reviews three aspects of complement in xenotransplantation. These include the mechanisms and regulation of complement activation as well as tissue injury mediated by complement activation.
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Affiliation(s)
- S Saadi
- Transplantation Biology, Mayo Clinic, Rochester, MN 55905, USA.
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25
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Rebhandl W, Saadi S, Herneth AM, Presterl E, Kurosh P, Wandl-Vergesslich K, Horcher E. Successful conservative treatment of severe renal candidosis with fungus balls. Pediatr Nephrol 1999; 13:688-92. [PMID: 10502128 DOI: 10.1007/s004670050682] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Partial fungal obstruction of the renal collecting system is an unusual finding among infants that poses specific management problems. We report a patient with sepsis and fungal infection of the kidneys post surgery who presented with bilateral fungus balls and was successfully managed by conservative measures. Sonography is the imaging technique of choice in the diagnosis and follow-up of such patients. The need for prompt diagnosis in high-risk patients and the role of sonography are discussed.
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Affiliation(s)
- W Rebhandl
- Department of Pediatric Surgery 6B, Vienna General Hospital, AKH Wien, University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria.
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26
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Abstract
A representative random sample of 597 Arab school-teachers in northern Israel, was surveyed regarding sources and levels of knowledge and attitudes about dental caries prevention. Data were measured according to a self-administered questionnaire from a 91.4 per cent response rate. When ranking the effectiveness of different caries preventive measures teachers on average listed optimal water fluoridation as a lower priority compared to toothbrushing, dental visits, fluoride mouthrinses and eating fewer sweet products. Placing of fissure sealants was ranked as the second least effective caries preventive measure, with 39.6 per cent not knowing the effectiveness. Only 68.5 per cent of the school-teachers were aware of the anti-bacterial role of fluoride, and only a small minority knew of fluoride's potential in healing incipient caries. Teachers seemed less motivated to being involved in dental health school programmes which involved dedicating school time and their active involvement, such as fissure sealant programmes at school, supervision of brushing and flossing, and school mouthrinsing programmes. They revealed positive attitudes towards: informing parents about the importance of oral hygiene and teaching children about preventive dentistry. Teachers' main reported source of knowledge was the dental office. It is the responsibility of the dental profession to ensure that updated knowledge is correctly conveyed to schoolteachers, who are an important and potentially influential sector of dental health consumers and health education agents.
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Affiliation(s)
- H D Sgan-Cohen
- Department of Community Dentistry, Hebrew University-Hadassah, Faculty of Dental Medicine, Jerusalem, Israel
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27
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Abstract
The complement system contributes critically to the barrier to transplantation of cells and organs. In the case of tissues and organs transplanted between individuals of the same species, that is in allotransplantation, the barrier posed by complement is seemingly eclipsed by the barrier posed by cellular immune responses. In the case of cells and organs transplanted between individuals of disparate species, that is xenotransplantation, the complement system has been thought to pose a nearly insurmountable barrier. With our understanding on how the complement system contributes to rejection, it is now clear that the complement system is more important in allotransplantation and more forgiving in xenotransplantation than was previously thought.
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Affiliation(s)
- J L Platt
- Transplantation Biology, Mayo Clinic, Rochester, MN 55905, USA.
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28
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Saadi S, Takahashi T, Nagayasu T, Holzknecht RA, Platt JL. The role of cytokines in rejection of discordant xenotransplants. Transplant Proc 1999; 31:911-2. [PMID: 10083400 DOI: 10.1016/s0041-1345(98)01831-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- S Saadi
- Department of Surgery, Mayo Clinic, Rochester, Minnesota 55905, USA
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29
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Abstract
The transplantation of tissues and organs between individuals of different species, that is, xenotransplantation, engenders a variety of immune responses. Xenogeneic immune responses mediated by naturally-occurring antibodies and complement lead to hyperacute and acute vascular rejection of vascularized organ grafts and may also cause vascular rejection of cell and tissue grafts. Under some circumstances, however, a vascularized organ graft may evade humoral rejection despite the presence of anti-donor antibodies in the circulation of the recipient; this condition is called accommodation. Xenogeneic immune responses mediated by T lymphocytes and natural killer cells may cause acute cellular rejection. The extent to which cellular rejection of xenografts resembles cellular rejection of allografts remains to be determined. New insights into the molecular mechanisms underlying the immune responses to xenotransplantation has shed light on the pathogenesis of immunological disease and has allowed the development of specific immunomodulatory strategies that may facilitate clinical application of xenotransplantation.
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Affiliation(s)
- S Saadi
- Department of Surgery, Duke University Durham, North Carolina 27710, USA
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30
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Malyguine AM, Saadi S, Holzknecht RA, Patte CP, Sud N, Platt JL, Dawson JR. Induction of procoagulant function in porcine endothelial cells by human natural killer cells. The Journal of Immunology 1997. [DOI: 10.4049/jimmunol.159.10.4659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
NK cells may mediate effector functions other than target cell cytotoxicity. To explore such noncytotoxic effector mechanisms, we tested whether human PBL and purified NK (CD56+) cells might induce expression of tissue factor by cultured porcine aortic endothelial cells. Tissue factor is the major coagulation factor that binds to factor VIIa and initiates coagulation. The addition of freshly isolated NK cells but not T cells to endothelial cells resulted in the induction of tissue factor activity. NK-depleted (CD56-) effector cells did not induce tissue factor activity; however, the combination of CD56+ cells and NK-depleted cells induced tissue factor activity to the same extent as unseparated cells. PBL induced tissue factor mRNA in porcine endothelial cells and NK depletion resulted in a significant decrease of the induction. Induction of tissue factor activity in porcine endothelial cells by human NK cells required direct cell-to-cell contact, as transfer of supernatants from NK-endothelial cell cultures to secondary cultures did not induce tissue factor activity, and anti-LFA-1alpha Abs inhibited the induction of tissue factor activity. Induction of tissue factor activity in endothelial cells by NK cells may represent one of a variety of ways in which NK cells mediate noncytotoxic effects.
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Affiliation(s)
- A M Malyguine
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - S Saadi
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - R A Holzknecht
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - C P Patte
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - N Sud
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - J L Platt
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - J R Dawson
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
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31
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Malyguine AM, Saadi S, Holzknecht RA, Patte CP, Sud N, Platt JL, Dawson JR. Induction of procoagulant function in porcine endothelial cells by human natural killer cells. J Immunol 1997; 159:4659-64. [PMID: 9366388] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
NK cells may mediate effector functions other than target cell cytotoxicity. To explore such noncytotoxic effector mechanisms, we tested whether human PBL and purified NK (CD56+) cells might induce expression of tissue factor by cultured porcine aortic endothelial cells. Tissue factor is the major coagulation factor that binds to factor VIIa and initiates coagulation. The addition of freshly isolated NK cells but not T cells to endothelial cells resulted in the induction of tissue factor activity. NK-depleted (CD56-) effector cells did not induce tissue factor activity; however, the combination of CD56+ cells and NK-depleted cells induced tissue factor activity to the same extent as unseparated cells. PBL induced tissue factor mRNA in porcine endothelial cells and NK depletion resulted in a significant decrease of the induction. Induction of tissue factor activity in porcine endothelial cells by human NK cells required direct cell-to-cell contact, as transfer of supernatants from NK-endothelial cell cultures to secondary cultures did not induce tissue factor activity, and anti-LFA-1alpha Abs inhibited the induction of tissue factor activity. Induction of tissue factor activity in endothelial cells by NK cells may represent one of a variety of ways in which NK cells mediate noncytotoxic effects.
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Affiliation(s)
- A M Malyguine
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
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32
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Bustos M, Coffman TM, Saadi S, Platt JL. Modulation of eicosanoid metabolism in endothelial cells in a xenograft model. Role of cyclooxygenase-2. J Clin Invest 1997; 100:1150-8. [PMID: 9276732 PMCID: PMC508290 DOI: 10.1172/jci119626] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Lipid inflammatory mediators are thought to play a critical role in the pathogenesis of vascular injury. Among the events which might cause the synthesis of eicosanoids in blood vessels is activation of the complement. To evaluate how complement might influence eicosanoid metabolism, we investigated endothelial cells exposed to xenoreactive antibodies and complement, as might occur in rejecting xenografts where severe vascular injury is a typical feature. While resting porcine aortic endothelial cells released only prostaglandin (PG) I2, endothelial cells stimulated with xenoreactive antibodies and complement released PGE2 and thromboxane A2 (TXA2), in addition to increased amounts of PGI2. This alteration in eicosanoid metabolism was associated with induction of cyclooxygenase (Cox)-2 and thromboxane synthase, but not Cox-1. Unlike results seen in other systems, the upregulation of Cox-2 and the subsequent release of eicosanoids by endothelial cells was not directly induced by complement but rather required production of IL-1alpha, which acted on endothelial cells as an autocrine factor. Since eicosanoids have a potent effect on inflammation, vascular tone and platelet aggregation, we postulated that the abnormalities in eicosanoid release induced by xenoreactive antibodies and complement might provide one explanation for the vascular injury, focal ischemia, and thrombosis observed in acute vascular rejection and other vasculitides mediated by complement.
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Affiliation(s)
- M Bustos
- Department of Surgery, Duke University, Durham, North Carolina 27710, USA
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33
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Abstract
The transplantation of tissue and organs between individuals of different species, that is xenotransplantation, engenders a variety of severe immune responses. Xenogeneic immune responses mediated by naturally occurring antibodies and complement lead to hyperacute and acute vascular rejection of vascularized organ grafts and may also cause vascular rejection of cell and tissue grafts. Under some circumstances, however, a vascularized organ graft may evade humoral rejection despite the presence of antidonor antibodies in the circulation of the recipient; this condition is called accommodation. Xenogeneic immune responses mediated by T-lymphocytes and natural killer cells may cause acute cellular rejection. The extent to which cellular rejection of xenografts resembles cellular rejection of allografts remains to be determined. New insights into the molecular mechanisms underlying the immune responses to xenotransplantation have shed new light on the pathogenesis of immunological disease and have allowed the development of specific immunomodulatory strategies that may facilitate clinical application of xenotransplantation.
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Affiliation(s)
- T Takahashi
- Department of Surgery, Duke University, Durham, NC 27710, USA
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34
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Platt JL, Parker W, Lin SS, Holzknecht Z, Saadi S. Role of Natural Antibody-Antigen Interactions in Xenotransplantation. Xenotransplantation 1997. [DOI: 10.1007/978-3-642-60572-7_3] [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: 12/01/2022]
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35
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Abstract
The use of baboons as a model for the study of allo- and xenotransplantation has become increasingly important, but there are few studies on the basic immunological responses in baboons that might be relevant for a rejection reaction. In present study, the cell-surface phenotype, cytokine-induced activation and growth, and cytotoxicity of baboon and human natural killer (NK) and lymphokine-activated killer (LAK) cells were compared. A panel of murine monoclonal antibodies specific for human cell-surface markers expressed on lymphocytes was used to compare relevant baboon and human peripheral blood lymphocytes (PBL). Baboon PBL were 52.1+/-2.9% CD8+, 18.5+/-2.2% CD16+, 3.0+/-0.5% CD25+, and 5.5+/-1.8% CD69+. The corresponding proportions in humans were 23.8+/-7.1%, 12.8+/-3.2%, 4.5+/-1.0%, and 2.3+/-1.1%. In contrast to human PBL, less than 1% of baboon lymphocytes expressed CD56, CD57, and CD122 (interleukin [IL]-2Rbeta). Baboon lymphocytes showed NK cytotoxic activity against the human K562 and CEM cell lines, which was comparable to human NK activity. Depletion of baboon CD16+ or CD8+ cells led to dramatic decreases in NK cytotoxicity, and removal of both subsets completely abrogated NK activity. Incubation of baboon lymphocytes with human recombinant IL-2 for 1 week led to the appearance of CD56+ cells (11.3+/-2.8%). Most of the baboon CD56+ cells induced in culture were in S and G2 phases of cell cycle. Both baboon and human IL-2-activated lymphocytes were highly cytotoxic against the human LAK-sensitive cell line Daudi. Depletion of baboon CD8+ but not CD56+ cells significantly decreased LAK activity. These studies revealed differences in the NK system of humans and baboons that should be taken into consideration when analyzing immune responses to allo- and xenotransplantation in baboons.
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Affiliation(s)
- A M Malyguine
- Department of Immunology, Duke University Medical Center, Durham, North Carolina 27710, USA
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36
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Abstract
Six years ago, Jeffrey Platt and colleagues reviewed the biological hurdles to transplanting organs between species. The ensuing years have allowed the concepts advanced at that time to be tested leading to significant progress in understanding the immunology of xenotransplantation and in developing strategies for potential clinical application. Here, William Parker and colleagues review that progress.
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Affiliation(s)
- W Parker
- Dept of Surgery, Duke University, Durham, NC 27710, USA
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37
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Bustos M, Saadi S, Platt JL. Modulation of endothelial metabolism by xenogeneic serum: implications for vasoconstriction and permeability. Transplant Proc 1996; 28:624. [PMID: 8623308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- M Bustos
- Department of Surgery, Duke University, Durham, North Carolina, USA
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38
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Abstract
In this study, we have investigated the early in vitro effects of natural killer (NK) cells on porcine aortic endothelial cell (PAEC) monolayers. Incubation of effector cells containing about 70% CD56+ cells on PAEC monolayer led to time-dependent changes in PAEC monolayer morphology. As little as 20 min of incubation resulted in changes in PAEC shape and in the appearance of gaps between the cells. These effects have been observed for up to 6 hr, but not before 20 min or after 6 hr. When NK-depleted effector cells were used, no morphological changes were observed in comparison with the same effectors before depletion; if CD56+ cells were added back, the effects were comparable with those on nondepleted effector cells. There was no detectable NK cell-mediated cytolytic activity during the 1-6 hr of incubation of peripheral blood lymphocytes with PAEC monolayers. These data indicate that NK cells may participate in endothelial cell changes leading to xenograft rejection.
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Affiliation(s)
- A M Malyguine
- Department of Immunology, Duke University Comprehensive Cancer Center, Duke University Medical Center, Durham, North Carolina 27710, USA
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39
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Abstract
Inflammation and immunity may be associated with endothelial cell (EC) injury and thrombus formation. We explored the mechanisms through which a humoral immune response directed against the endothelium might promote coagulation. Using the interaction of anti-EC antibodies and complement (C) with cultured EC as a model, we studied the expression and function of tissue factor, a cofactor for factor VIIa-mediated conversion of factor X to Xa. Exposure of EC to anti-EC antibodies and C in sublytic amounts stimulated the synthesis of tissue factor over a period of 16-42 h. Cell surface expression of tissue factor activity required activation of C and assembly of the membrane attack complex, because expression was inhibited by soluble CR1 and was not detected in the absence of C8. Elaboration of tissue factor messenger RNA was observed over a period of 8-30 h and required protein synthesis. Expression of tissue factor was not a direct consequence of the action of C on the EC but was a secondary response that required as an intermediate step the release of interleukin 1 alpha, an early product of the EC response to C activation. These findings suggest that, after the assembly of membrane attack complex on EC, the production of tissue factor and initiation of coagulation in a blood vessel depend on the production of interleukin 1 alpha and on its availability to stimulate affected EC.
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Affiliation(s)
- S Saadi
- Department of Surgery, Duke University, Durham, North Carolina 27710, USA
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40
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Abstract
The barrier function of blood vessels is though to be regulated at least in part by endothelium. This concept is supported by the dramatic loss of barrier function occurring in the hyperacute rejection of vascularized grafts mediated by anti-endothelial cell (EC) antibodies and complement. In this process, the endothelium is not destroyed but instead loses the ability to retain blood cells and plasma proteins within capillaries. The noncytotoxic mechanism that allows this change in EC function has been unknown. Here we report that within 10 to 20 min of exposure to human xenoreactive natural antibodies and complement, porcine EC undergo alterations in cell shape and in the cytoskeleton that disrupt monolayer integrity and lead to formation of intercellular gaps. Gap formation is not associated with cell death but requires the complement complex C5b67. The gaps induced by anti-EC antibodies and complement are transient; gap closure requires formation of C5b-9 complexes on the cells and the rate of recovery depends on the release of cellular products into the medium. Preincubation of EC with dibutyryl cAMP (0.5 mM) prevents gap formation and disruption of the cytoskeleton caused by antibodies and complement. These results provide evidence that the integrity of endothelium is regulated by components of the complement system and suggest a mechanism that may explain the prominent loss of endothelial integrity seen in humoral immune responses.
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Affiliation(s)
- S Saadi
- Department of Surgery, Duke University, Durham, North Carolina 27710
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41
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Saadi S, Ihrcke NS, Platt JL. Endothelial cell shape and hyperacute rejection. Transplant Proc 1994; 26:1149. [PMID: 8029864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- S Saadi
- Department of Surgery, Duke University, Durham, North Carolina 27710
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42
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Goncharoff P, Saadi S, Chang CH, Saltman LH, Figurski DH. Structural, molecular, and genetic analysis of the kilA operon of broad-host-range plasmid RK2. J Bacteriol 1991; 173:3463-77. [PMID: 2045366 PMCID: PMC207960 DOI: 10.1128/jb.173.11.3463-3477.1991] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The kil loci (kilA, kilB, kilC, and kilE) of incompatibility group P (IncP), broad-host-range plasmid RK2 were originally detected by their potential lethality to Escherichia coli host cells. Expression of the kil determinants is controlled by different combinations of kor functions (korA, korB, korC, and korE). This system of regulated genes, known as the kil-kor regulon, includes trfA, which encodes the RK2 replication initiator. The functions of the kil loci are unknown, but their coregulation with an essential replication function suggests that they have a role in the maintenance or host range of RK2. In this study, we have determined the nucleotide sequence of a 3-kb segment of RK2 that encodes the entire kilA locus. The region encodes three genes, designated klaA, klaB, and klaC. The phage T7 RNA polymerase-dependent expression system was use to identify three polypeptide products. The estimated masses of klaA and klaB products were in reasonable agreement with the calculated molecular masses of 28,407 and 42,156 Da, respectively. The klaC product is calculated to be 32,380 Da, but the observed polypeptide exhibited an apparent mass of 28 kDa on sodium dodecyl sulfate-polyacrylamide gels. Mutants of klaC were used to confirm that initiation of translation of the observed product occurs at the first ATG in the klaC open reading frame. Hydrophobicity analysis indicated that the KlaA and KlaB polypeptides are likely to be soluble, whereas the KlaC polypeptide was predicted to have four potential membrane-spanning domains. The only recognizable promoter sequences in the kilA region were those of the kilA promoter located upstream of klaA and the promoter for the korA-korB operon located just downstream of a rho-independent terminatorlike sequence following klaC. The transcriptional start sites for these promoters were determined by primer extension. Using isogenic sets of plasmids with nonpolar mutations, we found that klaA, klaB, and klaC are each able to express a host-lethal (Kil+) phenotype in the absence of kor functions. Inactivation of the kilA promoter causes loss of the lethal phenotype, demonstrating that all three genes are expressed from the kilA promoter as a multicistronic operon. We investigated two other phenotypes that have been mapped to the kilA region of RK2 or the closely related IncP plasmids RP1 and RP4: inhibition of conjugal transfer of IncW plasmids (fwB) and resistance to potassium tellurite. The cloned kilA operon was found to express both phenotypes, even in the presence of korA and korB, whose functions are known to regulate the kilA promoter. In addition, mutant and complementation analyses showed that the kilA promoter and the products of all three kla genes are necessary for expression of both phenotypes. Therefore, host lethality, fertility inhibition, and tellurite resistance are all properties of the kilA operon. We discuss the possible role of the kilA operon for RK2.
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Affiliation(s)
- P Goncharoff
- Department of Microbiology, College of Physicians and Surgeons, Columbia University, New York, New York 10032
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43
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Abstract
The initiator protein RepA1 of the IncFII replicon RepFIC derived from the enterotoxin plasmid EntP307 has been cloned under the control of the lambda PL promoter. This has enabled us to overproduce this protein and study its properties. Here we show that RepA1 is a soluble basic protein with an experimentally determined molecular weight of 40,000. Deletion analysis indicates that the overproduced protein originates from the open reading frame which we previously designated as coding for RepA1. We have also shown that the replication function of the replicon RepFIC depends on the intact RepA1 coding frame.
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Affiliation(s)
- R Maas
- Department of Microbiology, New York University Medical Center, New York 10016
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44
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Ayres EK, Saadi S, Schreiner HC, Thomson VJ, Figurski DH. Differentiation of lethal and nonlethal, kor-regulated functions in the kilB region of broad host-range plasmid RK2. Plasmid 1991; 25:53-63. [PMID: 1852017 DOI: 10.1016/0147-619x(91)90006-i] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In broad host-range plasmid RK2, several kil loci (kilA, kilB, kilC, kilE) and the replication initiator gene (trfA) are regulated by combination of kor determinants (korA, korB, korC, korE) in a regulatory network known as the kil-kor region. Although the kil determinants are not essential for replication, their coregulation with trfA suggests an involvement in plasmid maintenance or host-range. Plasmids carrying the cloned kilB region of RK2 cannot be maintained in the absence of korB owing to two phenotypically distinguishable, kor-regulated determinants: (1) kilB1 (kilD), which can be controlled by korA or korB, and (2) kilB2, which requires korB for control. In this study, we have determined the nature of the functions responsible for the kor-sensitive phenotypes of the kilB region. We found that insertion of transcription terminators within or downstream of the trfA operon allows plasmids carrying the kilB1 portion of the kilB region to be maintained in cells lacking korA or korB. In addition, mutants of the kilB1 region that can be maintained in the absence of korA and korB have alterations in the trfA promoter. These results show that the phenotype of the cloned kilB1 region in kor-deficient cells depends on trfA transcription but does not involve expression of any gene of the trfA operon. Therefore, the kilB1 determinant is not a structural gene. The phenotype results from entry of trfA-initiated transcription into adjacent sequences of the plasmid vector. The ability to block the kilB2 phenotype with transcriptional terminators allowed us to show conclusively that the kilB2 determinant is a host-lethal gene (klbA) whose regulation is dependent on korB. These findings have implications for the structure of the basic replicon of RK2.
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Affiliation(s)
- E K Ayres
- Department of Microbiology and Cancer Center, College of Physicians and Surgeons, Columbia University, New York, New York 10032
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Abstract
Many plasmids belonging to the F incompatibility groups contain more than one basic replicon. The chimeric plasmid pCG86 is an example of such a multireplicon plasmid. The two basic replicons of pCG86, RepFIIA/FIC and RepFIB have been cloned and re-ligated, the copy numbers of the clones have been determined, and the incompatibility behavior of plasmids containing the ligated replicons and the individual replicons has been studied. The bireplicon plasmids are not expected to be incompatible as recipients with monoreplicon RepFIB or RepFIIA/RepFIC plasmids, since when one replicon is challenged by an incoming replicon, the other should be able to handle the plasmid's replication. In our studies, we found that challenge with either monoreplicon plasmid resulted in incompatibility. This incompatibility was increased in bireplicon plasmids in which RepFIB was duplicated. We conclude that in the bireplicon plasmids, challenging the replication control of one replicon by an incompatible plasmid can interfere with the replication originating from the second replicon.
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Affiliation(s)
- R Maas
- Department of Microbiology, New York University Medical Center, NY 10016
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Silva RM, Saadi S, Maas WK. A basic replicon of virulence-associated plasmids of Shigella spp. and enteroinvasive Escherichia coli is homologous with a basic replicon in plasmids of IncF groups. Infect Immun 1988; 56:836-42. [PMID: 3278983 PMCID: PMC259378 DOI: 10.1128/iai.56.4.836-842.1988] [Citation(s) in RCA: 25] [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] [Indexed: 01/05/2023] Open
Abstract
Shigella species and enteroinvasive Escherichia coli strains carry a large (120- to 140-megadalton) plasmid called pINV, which contains genes essential for the invasiveness of these pathogens. Hybridization with specific probes derived from the RepFIC and RepFIB replicons of the IncF1 Ent plasmid P307 showed that pINVs present in 35 clinical isolates are homologous with RepFIC but not RepFIB, regardless of the serogroup of the Shigella or E. coli strain. RepFIC of P307, in turn, is very similar to RepFIIA replicons of IncFII R plasmids. These and other related replicons constitute the RepFIIA family. With one pINV, pWR110, a plasmid of Shigella flexneri 5, we demonstrated the existence of a functional replicon, RepINV, with a restriction map similar to that of RepFIIA of plasmid R1. We isolated the putative inc RNA coding region of RepINV, which is a major determinant of incompatibility. The nucleotide sequence of the RepINV-inc RNA-coding region was determined and compared with the corresponding sequences of RepFIC and RepFIIA. The differences were small, but apparently were sufficient to affect the target specificity of the inc RNAs, thus rendering the replicons compatible with each other. We conclude that pINVs present in Shigella spp. and enteroinvasive E. coli constitute a homogeneous group, containing one basic replicon that belongs to the RepFIIA family of replicons.
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Affiliation(s)
- R M Silva
- Department of Microbiology, Parasitology, Immunology and Mycology, Escola Paulista de Medicina, Sao Paulo, Brazil
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47
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Efthymiou CJ, Saadi S, Young SL, Helfand EA. Iron-deficient medium for selective isolation and presumptive identification of enterococci. Ann Clin Lab Sci 1987; 17:226-31. [PMID: 3304123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
An Enterococcus Selective Agar (ESA; basal medium plus 0.01% NaN3, pH 9.6, Fe ion-restricted) was applied to a direct, single-step, isolation and presumptive identification of enterococci from clinical urine. The ESA was examined as to rate of colony formation and selectivity together with two conventional culture media, Pfizer Selective Enterococcus Agar (PSE) and Phenyl Ethyl Alcohol Agar (PEA). Significant differences were observed in the rate of colony formation after 14, 17, and 20 hr of incubation at 35 degrees. The size of colonies on ESA was consistently larger than on the other two media. Biochemical testing showed that isolates from ESA conformed more closely to the definition of enterococci than isolates from either PSE or PEA. The improved selectivity of ESA was in large part due to the reduced presence of Fe ions. The medium offers advantages for an expeditious and accurate isolation of enterococcal pathogens.
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Saadi S, Maas WK, Hill DF, Bergquist PL. Nucleotide sequence analysis of RepFIC, a basic replicon present in IncFI plasmids P307 and F, and its relation to the RepA replicon of IncFII plasmids. J Bacteriol 1987; 169:1836-46. [PMID: 3032897 PMCID: PMC212033 DOI: 10.1128/jb.169.5.1836-1846.1987] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
RepFIC is a basic replicon of IncFI plasmid P307 which is located within a 3.09-kilobase SmaI fragment. The nucleotide sequence of this region has been determined and shown to be homologous with the RepFIIA replicon of IncFII plasmids. The two replicons share three homologous regions, HRI, HRII, and HRIII, which are flanked by two nonhomologous regions, NHRI and NHRII. A comparison of coding regions reveals that the two replicons have several features in common. RepFIC, like RepFIIA, codes for a repA2 protein with its amino-terminal codons in HRI and its carboxy-terminal codons in NHRI. Although the codons for the repA1 proteins are located in NHRII, the DNA region containing a putative promoter, ribosomal binding site, and initiation codons is located in HRII. This region also codes for an inc RNA. There are nine base-pair differences between the inc RNA of RepFIIA and that of RepFIC, and as a result, RepFIC and RepFIIA replicons are compatible. An EcoRI fragment from the F plasmid which shows homology with RepFIC of P307 has also been sequenced. This fragment contains only a portion of RepFIC, including the genes for the putative repA2 protein and inc RNA. The region coding for a putative repA1 protein is interrupted by the transposon Tn1000 and shows no homology with the repA1 region of RepFIIA and RepFIC of P307. Our comparative and structural analyses suggest that RepFIC and RepFIIA, although different, have a similar replication mechanism and thus can be assigned to the same replicon family, which we designate the RepFIIA family.
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49
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Abstract
Plasmids encoding F-like pili have been divided into groups on the basis of their incompatibility behavior. Three basic replicons have been recognized previously in the IncFI plasmid group and we have now examined their distribution in representative plasmids from 22 of the currently recognized incompatibility groups. The occurrence of these basic replicons was found to be rare outside of the IncF group, and significant hybridization was shown only for RepFIA to IncH1 and I group plasmids. Homology to the RepFIC basic replicon was found in all but one of the IncF group plasmids examined but RepFIA and RepFIB have a more restricted distribution. It appears likely that some plasmids carry vestiges of replicons which still express incompatibility but are incapable of replication. We suggest that evolutionary divergence among the plasmids of the IncF group has resulted from various genetic rearrangements among these basic replicons.
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Picken RN, Mazaitis AJ, Saadi S, Maas WK. Characterization of the basic replicons of the chimeric R/Ent plasmid pCG86 and the related Ent plasmid P307. Plasmid 1984; 12:10-8. [PMID: 6494315 DOI: 10.1016/0147-619x(84)90062-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Restriction-enzyme fragments that can replicate autonomously after circularization were isolated from the chimeric R/Ent plasmid pCG86 and the Ent plasmid P307. Two such regions containing a basic replicon were located in each plasmid. One of the basic replicons of P307, RepFIB, is almost identical with one of the basic replicons of pCG86. The other basic replicon in P307, RepFIC, is partly homologous with the second basic replicon in pCG86, RepFIIA/RepFIC. The latter is a hybrid basic replicon and is in addition partly homologous with RepFIIA, a basic replicon present in IncFII R plasmids. By restriction-enzyme mapping and nucleotide-sequence analysis we have determined a site in the hybrid replicon where it ceases to be homologous with the RepFIIA basic replicon contained in the IncFII miniplasmid pSM1. The 2410-bp region of homology with pSM1 corresponds with a segment containing the origin of replication and all the genes responsible for replication control of pSM1.
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