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1.
Senem Maral Muradiye Acar Ozlem Sahin Balcik Eyyup Uctepe Omer Faruk Hatipoglu Derya Akdeniz Hatice Uludag Altun Ali Kosar Mehmet Gunduz Esra Gunduz 《Medicine》2015,94(16)
Chronic myeloproliferative disorders such as polycythemia vera (PV), essential thrombocytosis (ET), and idiopathic myelofibrosis arise from clonal proliferation of neoplastic stem cells in the bone marrow. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that have potential to degrade all types of extracellular matrix (ECM) and also play a role in remodeling of the ECM. It is known that MMPs play a role in bone marrow remodeling.The primary goal of our study is to explore the relationship between chronic myeloproliferative diseases and some of MMP gene polymorphisms. The demonstration of a relationship will help to understand whether these polymorphisms may be a potential early diagnosis marker of the diseases.Patients were selected from outpatient clinics of Turgut Ozal University Hospital, Ankara, Turkey, between December 2010 and May 2011. Twenty-eight patients that previously diagnosed and followed-up with PV, 17 with secondary polycythemia (SP), and 12 with ET were enrolled in the study, along with a control group of 22 healthy people.DNA was isolated from peripheral blood. Using polymerase chain reaction–restriction fragment length polymorphism method, MMP2 and MMP9 gene polymorphisms were analyzed with agarose gel electrophoresis. There was a statistically significant difference between the study groups and the control group in terms of Gln279Arg polymorphisms rates of MMP9. The highest MMP9 Gln279Arg polymorphism rate was observed in the ET group. But nobody from the control group had polymorphic MMP9. There was no statistically significant difference between the groups in terms of MMP2-735 C > T polymorphism rates.In conclusion, MMP9 gene Gln279Arg polymorphism was associated with ET, SP, and PV diseases. Hence, we believe that these gene polymorphisms may play a role in the mechanism of bone marrow fibrosis and may be a factor that increases the risk of thrombosis. Illumination of the molecular basis of the relationship between MMP-thrombosis and MMP-fibrosis provides a better understanding of the pathophysiology of PV and ET diseases and will allow new approaches to diagnosis and treatment. 相似文献
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Emmanuel Lansac Isabelle Di Centa Nicolas Bonnet Pascal Leprince Akthar Rama Christophe Acar Alain Pavie Iradj Gandjbakhch 《European journal of cardio-thoracic surgery》2006,29(4):537-544
OBJECTIVE: Dilation of aortic annulus, sinuses of Valsalva, and sinotubular junction (STJ) diameters are the characteristic lesions of aortic root aneurysm. The remodeling technique reduces STJ diameter and creates three neosinuses of Valsalva. Alternatively, the reimplantation technique reduces both annulus and STJ diameters to the detriment of aortic root dynamics. Although the remodeling technique is recognized as the most physiological valve-sparing procedure, aortic annulus dilation may jeopardize its results. A standardized approach that combines an external subvalvular aortic prosthetic ring annuloplasty with the remodeling technique is suggested. METHODS: Eighty-three patients underwent an elective aortic root remodeling procedure, either isolated (group 1, n=34) or combined with an external subvalvular aortic prosthetic ring annuloplasty (group 2, n=49). Preoperative aortic regurgitation was 1.59+/-1.1 (group 1) and 1.97+/-1.3 (group 2) (NS). The aortic annulus was more dilated in group 2 than in group 1 (27+/-2.77 mm vs 26.4+/-2.3 mm, p<0.01). Residual aortic regurgitation > or =grade II was the conversion criteria for aortic valve replacement. RESULTS: Operative mortality was 3.6% (n=3). Intraoperative conversion for valve replacement was 32.7% in group 1 (n=11) versus 4.2% in group 2 (n=2) (p<0.001). In group 1, preoperative annulus diameter was larger for converted than for valve-spared patients (27.6+/-1.7 mm vs 25.2+/-1.5 mm, p<0.02). In group 2, implanted aortic ring significantly reduced annulus diameter (20.6+/-1.8 mm) without significant aortic valve gradient (8.3+/-3 mmHg). Follow-up was 17.2+/-13.4 months (group 1) and 10.41+/-7.95 months (group 2). Reoperation for recurrent aortic regurgitation was 13% in group 1 (n=3) versus 4.2% in group 2 (n=2). Echocardiographic follow-up found residual aortic regurgitation < or =grade I in 17 patients in group 1 (90%) versus 43 patients in group 2 (95.5%) and of grade II in two patients in group 1 (10%) and two patients in group 2 (4.5%). CONCLUSION: The addition of external aortic prosthetic ring annuloplasty improves the remodeling technique's operative reproducibility and short-term results. Therefore, its use as a systematical adjunct to the remodeling procedure is suggested. However, further long-term evaluation comparing this valve-sparing procedure to composite graft replacement should define the best surgical strategy for aortic root aneurysm. 相似文献
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H. H. Johnston J. F. Acar G. Linzenmeier A. Visconti 《European journal of clinical microbiology & infectious diseases》1982,1(4):204-211
The MS-2 is an instrument for rapid automated testing of antimicrobial susceptibility. Its performance was evaluated by comparison with disc diffusion and MIC tests in a collaborative study in four European laboratories. Tests on independently isolated organisms showed the MS-2 to be in essential agreement with conventional methods in 94.8% of tests. A further series of 170 welldefined pathogens for which a reference antibiogram was available were tested by MS-2 and the manual methods in all of the participating laboratories. MS-2 results were in full accord in 90 % of tests and in essential agreement in 94 %. MS-2 results compared at least as well with the reference values as did either of the manual methods. Initial problems of false susceptibility results with erythromycin and penicillin were resolved by (1) the addition of small amounts of erythromycin which acted as an inducer and (2) by the use of a low content penicillin disc. MS-2 was found to be reliable and needed no attention following loading of the test cuvette cartridges. A print-out of the results was available 2–5 h after inception of the test. 相似文献
6.
Odile Launay Jean-Claude Nguyen Van Annie Buu-Hoï J. F. Acar 《Clinical microbiology and infection》1997,3(5):541-544
Objective: To report a case of typhoid fever contracted in Portugal in 1994 due to a Salmonella typhi isolate which had reduced susceptibility to fluoroquinolone (MIC 1 mg/L of ciprofloxacin) and high level resistance to nalidixic acid (MIC ≥56 mg/L).
Methods: Molecular studies of reduced susceptibility to fluoroquinolones comprised complementation tests with a wild-type allele and sequencing directly from PCR products of the gyrA gene.
Results: Complementation tests and DNA sequencing showed that a mutation occurred in the gyrA gene of this clinical isolate, resulting in a substitution of phenylalanine for serine at position 83 of GyrA.
Conclusions: Because quinolones may be regarded as a treatment of choice in typhoid fever, it seems important now to recommend cautious use of these drugs as first-line therapy and possibly use of nalidixic acid resistance as a marker for detection of 'first-step' resistance to fluoroquinolones in S. typhi. 相似文献
Methods: Molecular studies of reduced susceptibility to fluoroquinolones comprised complementation tests with a wild-type allele and sequencing directly from PCR products of the gyrA gene.
Results: Complementation tests and DNA sequencing showed that a mutation occurred in the gyrA gene of this clinical isolate, resulting in a substitution of phenylalanine for serine at position 83 of GyrA.
Conclusions: Because quinolones may be regarded as a treatment of choice in typhoid fever, it seems important now to recommend cautious use of these drugs as first-line therapy and possibly use of nalidixic acid resistance as a marker for detection of 'first-step' resistance to fluoroquinolones in S. typhi. 相似文献
7.
F. W. Goldstein P. Geslin J. F. Acar 《European journal of clinical microbiology & infectious diseases》1994,13(1):33-34
The MICs of teicoplanin and vancomycin were determined for 400 penicillin-susceptible and -resistant strains ofStreptococcus pneumoniae isolated during a multicenter study in 1992. Teicoplanin displayed a four-fold better activity than vancomycin, with modal MICs of these agents being 0.06 and 0.25 µg/ml, respectively. These data warrant further studies with teicoplanin in the treatment of pneumococcal infections.J. Akli, Centre Hospitalier Général, 41016 Blois Cédex; P. Allouch, Hôpital André Mignot, 78157 Le Chesnay Cédex; C. Bébéar, Centre Hospitalier Pellegrin-Tripode, 33076 Bordeaux Cédex; P. Blondel, Centre Hospitalier Général, 93205 Saint-Denis Cédex 1; A. Boisivon, Centre Hospitalier Général, 78104 Saint-Germain en Laye; J.C. Burdin, Hôpital Central, 54035 Nancy Cédex; H. Chardon, Centre Hospitalier Général, 13616 Aix en Provence Cédex; A. Coupry, Nouvel Hôpital de Fleyrat, 01012 Bourg-en-Bresse Cédex; J.C. Croix, Centre Hospitalier Général, 10003 Troyes Cédex; G. Dorche, Hôpital Bellevue, 42043 Saint-Etienne Cédex; P. Fiévet, Centre Hospitalier, 59507 Douai Cédex; F. Geffroy, Centre Hospitalier René Laënnec, 29107 Quimper Cédex; P. Geslin, Centre Hospitalier Intercommunal, 94010 Créteil; M.L. Grillot, Hôpital Général, 76083 Le Havre Cédex; B. Hautefort, Centre Hospitalier Général, 13697 Arles Cédex; M. Larrouy, Centre Hospitalier Intercommunal de la Côte Basque, 64109 Bayonne; H. Lefrand, Hôpital Henri Duffaut, 84902 Avignon Cédex 9; J.F. Lemeland, Hôtel-Dieu, 76000 Rouen; J.M. Libert, Centre Hospitalier Mane-Lannelongue, 92350 Le Plesssis-Robinson; A. Marmonier, Centre Hospitalier, 72037 Le Mans Cédex; M. Melon, Centre Hospitalier Général, 64011 Pau Cédex; M.H. Nicolas, Hôpital Ambroise Paré, 92104 Boulogne; J.C. Reveil, Hôpital Manchester, 08011 Charleville-Mézières Cédex; Y. Rio, Hôpital Notre Dame de Bon Secours, 57038 Metz Cédex; R. Sanchez, Hôpital Général, 24019 Périgueux Cédex; A. Sédaillan, Centre Hospitalier, 74011 Annecy Cédex, France. 相似文献
8.
Capnocytophaga ochracea is a gram-negative, fusiform bacillus which is part of the normal human oral flora. This organism is often isolated from periodontal lesions of patients with periodontitis and is associated with sepsis in granulocytopenic patients. We report here a case of endocarditis caused by C. ochracea. 相似文献
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We have studied trisomy 12 in chronic lymphocytic leukemia (CLL) by fluorescence in situ hybridization (FISH) with an -satellite centromeric probe for chromosome 12 on both dividing and non-dividing cells. Trisomy for chromosome 12 was demonstrated in four of these patients (15.3%) using FISH on interphase cells. The percentage of trisomic cells ranged from 10% to 65% of nuclei. The hybridization signals in the trisomic and disomic nuclei were of a broadly similar size and nature. Interestingly, three of the remaining CLL patients, who exhibited disomy for chromosome 12, showed a marked difference in size of the hybridization signals in interphase nuclei. This was also demonstrated in metaphase spreads. In addition, metaphase FISH studies revealed a supernumerary marker chromosome in three out of 26 patients with CLL. 相似文献