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1.
Molecular Characterization of Vancomycin-Resistant Enterococci from Hospitalized Patients and Poultry Products in The Netherlands 总被引:9,自引:3,他引:9 下载免费PDF全文
Nicole van den Braak Alex van Belkum Marrit van Keulen John Vliegenthart Henri A. Verbrugh Hubert P. Endtz 《Journal of clinical microbiology》1998,36(7):1927-1932
Vancomycin-resistant enterococci (VRE) pose an emerging health risk, but little is known about the precise epidemiology of the genes coding for vancomycin resistance. To determine whether the bacterial flora of consumer poultry serves as a gene reservoir, the level of contamination of poultry products with VRE was determined. VRE were genotyped by pulsed-field gel electrophoresis (PFGE), and transposon structure mapping was done by PCR. The vanX-vanY intergenic regions of several strains were further analyzed by sequencing. A total of 242 of 305 (79%) poultry products were found to be contaminated with VRE. Of these VRE, 142 (59%) were high-level-vancomycin-resistant Enterococcus faecium strains (VREF). PFGE revealed extensive VREF heterogeneity. Two genotypes were found nationwide on multiple occasions: type A (22 of 142 VREF [15%]) and type B (14 of 142 VREF [10%]). No PFGE-deduced genetic overlap was found when VREF from humans were compared with VREF from poultry. Two vanA transposon types were identified among poultry strains. In 59 of 142 (42%) of the poultry VREF, the size of the intergenic region between vanX and vanY was ~1,300 bp. This transposon type was not found in human VREF. In contrast, all human strains and 83 of 142 (58%) of the poultry VREF contained an intergenic region 543 bp in size. Sequencing of this 543-bp intergenic vanX-vanY region demonstrated full sequence conservation. Though preliminary, these data suggest that dissemination of the resistance genes carried on transposable elements may be of greater importance than clonal dissemination of resistant strains. This observation is important for developing strategies to control the spread of glycopeptide resistance. 相似文献
2.
Immunogenic properties of octasaccharide-protein conjugates derived from Klebsiella serotype 11 capsular polysaccharide. 下载免费PDF全文
J W Zigterman J E van Dam H Snippe F T Rotteveel M Jansze J M Willers J P Kamerling J F Vliegenthart 《Infection and immunity》1985,47(2):421-428
The tetrasaccharide repeating unit of the capsular polysaccharide of Klebsiella serotype 11, K11PS, comprises the following sequence: [----3)-beta-D-GlcpA-(1----3)-alpha-D-Galp-(1----3)-beta-D-Glcp-(1 ----] with a 4,6-O-(1-carboxyethylidene)-alpha-D-galactopyranosyl residue linked to O-4 of the glucuronic acid residue. Octasaccharide (OS) derived from K11PS by bacteriophage phi 11-associated glycanase, was coupled to bovine serum albumin and to keyhole limpet hemocyanin. The immunogenicity of various antigens after intraperitoneal immunization was studied by measuring the levels of circulating antibodies. Injection of BALB/c mice with K11PS resulted in induction of 2-mercaptoethanol-sensitive immunoglobulin M antibodies. The responses observed in BALB/c nu/nu mice and in male (CBA/N X C3H/HeN)F1 mice indicate that K11PS is a thymus-independent type 2 antigen. Immunization of BALB/c mice with either OS-bovine serum albumin or OS-keyhole limpet hemocyanin resulted in the induction of circulating 2-mercaptoethanol-resistant immunoglobulin G antibodies. Results in BALB/c nu/nu mice indicate that the OS-protein conjugates are thymus-dependent antigens. Since the OS-keyhole limpet hemocyanin conjugate induced antibodies in both (CBA/N X C3H/HeN)F1 females and males, we propose to refer to this kind of antigen as a thymus-dependent type 1 antigen, whereas OS-bovine serum albumin, which evoked immunoglobulins in (CBA/N X C3H/HeN)F1 females only, can be referred to as a thymus-dependent type 2 antigen. 相似文献
3.
Isolation and structural characterization of the equine erythrocyte receptor for enterotoxigenic Escherichia coli K99 fimbrial adhesin 总被引:2,自引:12,他引:2 下载免费PDF全文
H Smit W Gaastra J P Kamerling J F Vliegenthart F K de Graaf 《Infection and immunity》1984,46(2):578-584
The erythrocyte receptor for Escherichia coli K99 fimbrial adhesin was isolated from equine erythrocytes and characterized as Neu5Gc-alpha(2----3)-Galp-beta(1----4)-GLcp-beta(1----1)-Ceramide. This glycolipid acted as the receptor for K99 by four different experimental approaches: inhibition of equine erythrocyte hemagglutination by preincubation of K99-positive bacteria or purified K99 fimbriae with the isolated glycolipid; inhibition of attachment of K99-positive bacteria to porcine intestinal epithelial cells in the presence of the isolated glycolipid; induction of binding of K99-positive bacteria or purified K99 fimbriae to normally unreactive guinea pig erythrocytes by coating these cells with the isolated glycolipid; and isolation of the receptor by affinity chromatography with K99 coupled to CNBr-activated Sepharose 4B, indicating a strong interaction between K99 and the isolated glycolipid. 相似文献
4.
Dirkjan Kuijpers Randy van Dijk Marly van Assen Theodorus A. M. Kaandorp Paul R. M. van Dijkman Rozemarijn Vliegenthart Pim van der Harst Matthijs Oudkerk 《The international journal of cardiovascular imaging》2018,34(4):625-632
Caffeine is an adenosine receptor antagonist and a possible cause of inadequate stress perfusion. Splenic switch-off (SSO) and splenic rest-stress T1-mapping have been proposed as indicators of stress adequacy during perfusion cardiac magnetic resonance (CMR). We compared myocardial rest-stress T1-mapping with SSO and splenic rest-stress T1-mapping in patients with and without recent coffee intake. We analyzed 344 consecutive patients suspected of myocardial ischemia with adenosine perfusion CMR. All 146 normal CMR studies with a normal T1-rest of the myocardium, used as standard of reference, were included and divided in two groups. 22 patients accidentally ingested coffee <?4 h before CMR, compared to control group of 124 patients without self-reported coffee intake. Two independent readers graded SSO visually. T1-reactivity (ΔT1) was defined as percentual difference in T1-rest and T1-stress. Follow-up data were extracted from electronic patients records. In patients with recent coffee intake SSO was identified in 96%, which showed no significant difference with SSO in controls (94%, p?=?0.835), however event rates were significantly different (13.6 and 0.8%, respectively (p?<?0.001), median FU 17 months). Myocardial ΔT1 in the coffee group (??5.2%) was significantly lower compared to control (+?4.0%, p?<?0.001), in contrast to the splenic ΔT1 (??3.7 and ??4.0%, p?=?0.789). The splenic T1-mapping results failed to predict false negative results. SSO and splenic rest-stress T1-mapping are not reliable indicators of stress adequacy in patients with recent coffee intake. Therefore, the dark spleen sign does not indicate adequate myocardial stress in patients with recent caffeine intake. Myocardial rest-stress T1-mapping is an excellent indicator of stress adequacy during adenosine perfusion CMR. 相似文献
5.
Arthur E. Stillman Matthijs Oudkerk David A. Bluemke Menko Jan de Boer Jens Bremerich Ernest V. Garcia Matthias Gutberlet Pim van der Harst W. Gregory Hundley Michael Jerosch-Herold Dirkjan Kuijpers Raymond Y. Kwong Eike Nagel Stamatios Lerakis John Oshinski Jean-François Paul Riemer H. J. A. Slart Vinod Thourani Rozemarijn Vliegenthart Bernd J. Wintersperger 《The international journal of cardiovascular imaging》2018,34(8):1249-1263
Non-invasive imaging plays a growing role in the diagnosis and management of ischemic heart disease from its earliest manifestations of endothelial dysfunction to myocardial infarction along the myocardial ischemic cascade. Experts representing the North American Society for Cardiovascular Imaging and the European Society of Cardiac Radiology have worked together to organize the role of non-invasive imaging along the framework of the ischemic cascade. The current status of non-invasive imaging for ischemic heart disease is reviewed along with the role of imaging for guiding surgical planning. The issue of cost effectiveness is also considered. Preclinical disease is primarily assessed through the coronary artery calcium score and used for risk assessment. Once the patient becomes symptomatic, other imaging tests including echocardiography, CCTA, SPECT, PET and CMR may be useful. CCTA appears to be a cost-effective gatekeeper. Post infarction CMR and PET are the preferred modalities. Imaging is increasingly used for surgical planning of patients who may require coronary artery bypass. 相似文献
6.
Yihui Du Qiong Li Grigory Sidorenkov Marleen Vonder Jiali Cai Geertruida H. de Bock Yu Guan Yi Xia Xiuxiu Zhou Di Zhang Mieneke Rook Rozemarijn Vliegenthart Marjolein A. Heuvelmans Monique D. Dorrius P.M.A. van Ooijen Harry J.M. Groen Pim van der Harst Yi Xiao Shiyuan Liu 《Academic radiology》2021,28(1):36-45
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Henk Broekhuizen Catharina G.M. Groothuis-Oudshoorn Rozemarijn Vliegenthart Harry J.M. Groen Maarten J. IJzerman 《Value in health》2018,21(11):1269-1277