Search

AbstractBackground:There is growing evidence that routine defibrillation threshold (DFT) testing during implantable cardioverter defibrillator (ICD) implantation is not necessary. However a small group of patients might be at risk if no DFT testing is performed.Methods:Patients with a new pectoral ICD implantation in our hospital between 2006 and 2014 were included in a retrospective registry. A clinical high DFT was defined as a safety margin <10 J of the maximal device output. Logistic regression for prediction of high DFT was performed using patient characteristics, clinical, echocardiographic and device-related parameters.Results:DFT testing was performed in 788/864 (91.2%) procedures. In 76 (8.8%) patients no DFT testing was performed mainly due to atrial fibrillation, intra-cardiac thrombus, hemodynamic instability or logistical reasons. A high DFT was present in 44 (5.6%) patients. A QRS duration ≥150 ms, a low left ventricular ejection fraction (LVEF ≤25%), a severely dilated left ventricle ≥60 mm and right sided pre-pectoral implantations were univariate predictors of a high DFT. Independent predictors of a high DFT were a LVEF ≤25% (HR 2.195, 95%CI 1.085–4.443) and right sided pre-pectoral implantations (HR 3.135, 95% CI 1.186–8.287).Conclusions:A high DFT is still present in about 5% of patients and is more frequent in patients with a severely dilated left ventricle, a very low LVEF, right sided pre-pectoral implantation and wider QRS duration. It might be clinically important to continue DFT testing in these high risk patients.

ABSTRACTFifteen percent of all methicillin-resistant Staphylococcus aureus(MRSA) clonal complex 398 (CC398) human carriers detected in The Netherlands had not been in direct contact with pigs or veal calves. To ensure low MRSA prevalence, it is important to investigate the likely origin of this MRSA of unknown origin (MUO). Recently, it was shown that CC398 strains originating from humans and animals differ in the presence of specific mobile genetic elements (MGEs). We hypothesized that determining these specific MGEs in MUO isolates and comparing them with a set of CC398 isolates of various known origin might provide clues to their origin. MUO CC398 isolates were compared to MRSA CC398 isolates obtained from humans with known risk factors, a MRSA CC398 outbreak isolate, livestock associated (LA) MRSA CC398 isolates from pigs, horses, chickens, and veal calves, and five methicillin-susceptible Staphylococcus aureus(MSSA) CC398 isolates of known human origin. All strains were spatyped, and the presence or absence of, scn, chp, f3 int, f6 int, f7 int, rep7, rep27, and cadDXwas determined by PCRs. The MRSA CC398 in humans, MUO, or MRSA of known origin (MKO) resembled MRSA CC398 as found in pigs and not MSSA CC398 as found in humans. The distinct human MSSA CC398 spatype, t571, was not present among our MRSA CC398 strains; MRSA CC398 was tetracycline resistant and carried no f3 bacteriophage with scnand chp. We showed by simple PCR means that human MUO CC398 carriers carried MRSA from livestock origin, suggestive of indirect transmission. Although the exact transmission route remains unknown, direct human-to-human transmission remains a possibility as well.

Abstract: Aims: We evaluate the incidence of epicardial lead failure and try to identify risk factors in patients with congenital heart disease.Methods: All patients with a congenital heart defect and an epicardial pacing system, implanted within a timeframe of 25 years, were included in this study. Patients’ medical records and lead data were reviewed. Lead failure was defined as the primary endpoint. Results: In total 198 active epicardial leads (atrial 40, ventricular 158) were implanted in 93 patients (median age at implantation 4.4 years (range 0–58.6)). During a total follow-up of 1235 lead-years, 29 lead failures (14.6%, 4 atrial, 25 ventricular) were documented in 22 patients (23.7%). Lead failure occurred at a median time period of 4.8 years (range 1.2–24.1) after implantation. Five-year freedom of lead failure was 88%. The only independent predictor for lead failure was the age at implantation (HR 0.44; 95%CI 0.20–0.97, p = 0.04), other characteristics failed to predict lead failure. Sudden cardiac death occurred in four patients (4.3%), in one a lead failure was documented. Conclusion: A high incidence of epicardial lead failures is found in patients with congenital heart disease. Unfortunately, it is difficult to predict this potentially life-threatening complication.

ABSTRACTMethicillin-resistant Staphylococcus aureus(MRSA) strains carrying the Panton-Valentine leucocidin (PVL) genes have been reported worldwide and are a serious threat to public health. The PVL genes encode a highly potent toxin which is involved in severe skin infections and necrotizing pneumonia, even in previously healthy individuals. We assessed the prevalence of PVL-positive MRSA in The Netherlands for two periods of time: (i) 1987 through 1995 and (ii) 2000 and 2002, and determined their characteristics by using multilocus sequence typing and staphylococcal chromosome cassette (SCCmec) typing. It was found that up to 15% of all MRSA isolates detected in The Netherlands harbored the PVL genes. Most PVL-positive MRSA isolates were obtained from severe soft tissue infections in relatively young individuals. The first PVL-positive MRSA described in The Netherlands, isolated in 1988, was a single-locus variant of the “Berlin” epidemic MRSA clone. The 20 PVL-positive MRSA isolates studied in 2000 and 2002 consisted of five different sequence types (STs) that belonged to four clonal complexes. One of the STs, ST80, is considered to be a widespread European clone and was the most predominant ST (60%) in this study, while ST37 had never been found to be associated with PVL-positive MRSA. Most isolates harbored SCCmectype IV, a supposed marker for community-acquired MRSA. The number and type of virulence-associated genes varied among the different STs.

In current scanning‐probe nanolithography research, substrates consisting of octadecyl trichlorosilane monolayers on silicon are often used. On one hand, the presence of an organic monolayer can be used as a passive resist, influencing the formation of silicon dioxide on the substrate, whereas in other cases the monolayer itself is patterned, creating local chemical functionality. In this study we investigate the time scales involved in either process. By looking at friction and height images of lines oxidized at different bias voltages and different pulse durations, we have determined the parameter space in which the formation of silicon dioxide is dominant as well as the region in which the oxidation of the monolayer itself is dominant.

ABSTRACTMethicillin-resistant Staphylococcus aureus(MRSA) is an important human pathogen and represents a growing public health burden due to the emergence and spread of epidemic strains, particularly within the hospital environment. An epidemic MRSA clone, with characteristic low-level resistance to oxacillin, emerged in the year 2000 and became endemic in the Netherlands. Multilocus sequence typing characterized the strain as sequence type 45, which was previously designated the Berlin epidemic MRSA clone. In 2 years, this strain has become the predominant MRSA clone in the Netherlands.

ABSTRACTThe emergence of glycopeptide-resistant Enterococcus faecium(GREF) in a Greek intensive care unit was studied by amplified fragment length polymorphism analysis and espgene detection. Three GREF clones harboring the espgene were recovered from 17 out of 21 patients, indicating the dissemination of genetically homogenous and virulent strains of GREF.

The existence of long-term (20–33 years) trendsin the annual totals of daily airborne pollenconcentrations of five common and/or allergenicwind pollinating taxa was evaluated at fivepollen-monitoring stations in western Europe:Delmenhorst (D), Helmond (NL), Brussels (B),Leiden (NL), and Derby (UK). At all stations,identical or comparable volumetric traps wereused to sample pollen from the air. For grasspollen no increasing or decreasing trends werefound at any station. Trends for birch pollenand oak pollen are increasing, but notsignificant at the stations with the higherannual totals (Delmenhorst and Helmond),probably due to strong year-to-yearfluctuations. At all five stations significantincreasing trends for stinging nettle pollenwere observed. Trends for mugwort pollen aresignificant at all stations, but in differentdirections. Longer periods of observations areneeded to arrive to more definitive conclusionsabout trends in airborne pollenconcentrations.

The ability to colonize patients successfully may be essential for the emergence and spread of resistant nosocomial strains. We determined the presence of Esp, a surface protein involved in colonization ability in Enterococcus faecalis, in 96 Enterococcus faecium isolates from hospitalized patients (77 PFGE clones), 33 faecal isolates from healthy volunteers (32 clones) and 20 environmental isolates (20 clones). Esp was found significantly more often in E. faecium isolated from hospitalized patients than in isolates from the community setting (26% versus 6%, P &lt; 0.01) and was significantly more common among ampicillin-resistant than among ampicillin-susceptible strains (37% versus 4%, P &lt; 0.001), regardless of the isolation site. The frequency of the esp gene in the hospital clearly correlates with antibiotic-resistant E. faecium clones. This observation indicates that antibiotic-resistant variants may frequently arise under antibiotic selective pressure among esp-positive clones reaching ecological abundance in the nosocomial habitat.

The prevalence of resistance in enterococci to antibiotics, commonly used for therapy in poultry or as antimicrobial growth promoters (AMGPs), was determined in faecal samples of two chicken populations: broilers in which antibiotic and AMGP use is common and laying-hens with a low antibiotic usage. In addition faecal samples were examined from three human populations: broiler farmers, laying-hen farmers and poultry slaughterers. MICs of an extended panel of antibiotics for a randomly chosen gentamicin- or vancomycin-resistant enterococcal isolate from each faecal specimen were also determined. The prevalence of resistance for all antibiotics tested was higher in broilers than in laying-hens. Resistance in faecal enterococci of broiler farmers was for nearly all antibiotics higher than those observed in laying-hen farmers and poultry slaughterers. The overall resistance in broilers was correlated with the resistance in broiler farmers and in poultry slaughterers. No correlation between the results obtained in the laying-hens with any of the other populations was found. The 27 gentamicin-resistant isolates all showed high-level resistance to gentamicin and two of these isolates, both Enterococcus faecium, were resistant to all antibiotics tested, except vancomycin. The 73 vancomycin-resistant enterococci (VRE) isolated from the five populations belonged to four different species and in all isolates the vanA gene cluster was detected by blot hybridization. The pulsed-field gel electrophoresis (PFGE) patterns of these vancomycin-resistant enterococci were quite heterogeneous, but Enterococcus hirae isolates with the same or a closely related PFGE pattern were isolated at two farms from the broiler farmer and from broilers. Molecular characterization of vanA-containing transposons of these isolates showed that similar transposon types, predominantly found in poultry, were present. Moreover, similar vanA elements were not only found in isolates with the same PFGE pattern but also in other VRE isolated from both humans and chickens. The results of this study suggest transmission of resistance in enterococci from animals to man. For VRE this might be clonal transmission of animal strains, but transposon transfer seems to occur more commonly.

ABSTRACTThe gram-negative bacterium Campylobacter jejunihas extensive reservoirs in livestock and the environment and is a frequent cause of gastroenteritis in humans. To date, the lack of (i) methods suitable for population genetic analysis and (ii) a universally accepted nomenclature has hindered studies of the epidemiology and population biology of this organism. Here, a multilocus sequence typing (MLST) system for this organism is described, which exploits the genetic variation present in seven housekeeping loci to determine the genetic relationships among isolates. The MLST system was established using 194 C. jejuniisolates of diverse origins, from humans, animals, and the environment. The allelic profiles, or sequence types (STs), of these isolates were deposited on the Internet (http://mlst.zoo.ox.ac.uk), forming a virtual isolate collection which could be continually expanded. These data indicated that C. jejuniis genetically diverse, with a weakly clonal population structure, and that intra- and interspecies horizontal genetic exchange was common. Of the 155 STs observed, 51 (26% of the isolate collection) were unique, with the remainder of the collection being categorized into 11 lineages or clonal complexes of related STs with between 2 and 56 members. In some cases membership in a given lineage or ST correlated with the possession of a particular Penner HS serotype. Application of this approach to further isolate collections will enable an integrated global picture of C. jejuniepidemiology to be established and will permit more detailed studies of the population genetics of this organism.

Nucleoside diphosphate kinases (Nm23/NDPK) are enzymes functional in cell proliferation, differentiation, development, tumor progression, and metastasis. Nevertheless, no consensus exists about the molecular mechanism by which Nm23/NDPK isoforms exert their role in these processes. We investigated the expression of the rat Nm23-R1/NDPKβ and Nm23-R2/NDPKα isoforms, homologues of the human Nm23-H1/NDPK A and Nm23-H2/NDPK B proteins, respectively, upon cAMP-induced differentiation of rat C6 glioma cells and demonstrated a differential interaction with intermediate filaments. Semiquantitative RT-PCR, immunoblotting, and flow cytometry showed a constitutive expression of both Nm23 isoforms. After induction of differentiation in C6 cells with cAMP analogs or isoproterenol, a dose-dependent 2- and 2.5-fold upregulation of the Nm23-R1 mRNA and protein, respectively, was observed. In contrast, the expression of Nm23-R2 remained unchanged. Localization of both isoforms with confocal laser scanning microscopy demonstrated a punctate reticular staining pattern for both Nm23 isoforms in the cytosol and processes of the cells which was particularly intense in the perinuclear region. In addition, while Nm23-R2 was colocalized and coimmunoprecipitated with vimentin in nondifferentiated cells, both isoforms were associated with GFAP in differentiated cells. The significance of these findings in relation to a possible function of Nm23 isoforms in cell proliferation, differentiation, and tumor-associated mechanisms is discussed.

In this paper we investigate the problem of controlled synchronization as a regulator problem. In controlled synchronization one is given autonomous transmitter dynamics and controlled receiver dynamics. The question is to find a (output) feedback controller that achieves matching between transmitter and controlled receiver. Several variants of the problem where the standard solvability assumptions for the regulator problem are not met turn out to have a solution. Simulations on two standard synchronization examples are also included. Copyright © 2000 John Wiley & Sons, Ltd.

The purpose of this case report is to describe a rare case of a patient with a phaeochromocytoma with several cardiovascular complications, which can be attributed to the tumour. Detection of a phaeochromocytoma sometimes needs a ‘Sherlock Holmes spirit’ or simply time.

During colonization of the respiratory tract by Bordetella pertussis, virulence factors contribute to adherence of the bacterium to the respiratory tract epithelium. In the present study, we examined the roles of the virulence factors filamentous hemagglutinin (FHA), fimbriae, pertactin (Prn), and pertussis toxin (PT) in the adherence of B. pertussis to cells of the human bronchial epithelial cell line NCI-H292 and of the laryngeal epithelial cell line HEp-2. Using B. pertussis mutant strains and purified FHA, fimbriae, Prn, and PT, we demonstrated that both fimbriae and FHA are involved in the adhesion of B. pertussis to laryngeal epithelial cells, whereas only FHA is involved in the adherence to bronchial epithelial cells. For PT and Prn, no role as adhesion factor was found. However, purified PT bound to both bronchial and laryngeal cells and as such reduced the adherence of B. pertussis to these cells. These data may imply that fimbriae play a role in infection of only the laryngeal mucosa, while FHA is the major factor in colonization of the entire respiratory tract.

Fimbriae belong to a class of extracellular filamentous proteins which are involved in the attachment of bacteria to host tissues. Bordetella pertussis, the etiological agent of whooping cough, produces two serologically distinct fimbriae. We show that, like a number of other B. pertussis virulence genes, transcription of the fimbrial subunit genes (fim) is positively controlled by trans‐acting polypeptides encoded by the bvg locus. In addition to this coordinate control, transcription of the fim genes is regulated at an individual level by phase variation. This process is characterized by a switching between a high and low level of expression of a particular fim gene. We have identified a conserved DNA region, located close to the start of the fim genes, which is likely to be involved in both positive regulation by the bvg locus, and phase variation. This promoter region contains a stretch of approximately 15 C residues and it appears that phase transitions occur by small insertions or deletions in this C‐rich region. We propose that these mutations affect transcription of the fim genes by varying the distance between the binding site for an activator and the −10 box. The fim promoter shows homology with the pertussis toxin promoter, which is also positively regulated by the bvg locus.

The Bordetella pertussis proteins P.69 (also designated pertactin) and pertussis toxin are important virulence factors and have been shown to confer protective immunity in animals and humans. Both proteins are used in the new generation of acellular pertussis vaccines (ACVs), and it is therefore important to study the degree of antigenic variation in these proteins. Sequence analysis of the genes for P.69 and the pertussis toxin S1 subunit, using strains collected from Dutch patients in the period 1949 to 1996, revealed three P.69 and three S1 variants which show differences in amino acid sequence. Polymorphism in P.69 was confined to a region comprised of repeats and located proximal to the RGD motif involved in adherence to host tissues. Variation in S1 was observed in two regions previously identified as T-cell epitopes. P.69 and S1 variants, identical to those included in the Dutch whole-cell pertussis vaccine (WCV), were found in 100% of the strains from the 1950s, the period when the WCV was introduced in The Netherlands. However, nonvaccine types of P.69 and S1 gradually replaced the vaccine types in later years and were found in approximately 90% strains from 1990 to 1996. These results suggest that vaccination has selected for strains which are antigenically distinct from vaccine strains. Analysis of strains from vaccinated and nonvaccinated individuals indicated that the WCV protects better against strains with the vaccine type P.69 than against strains with non-vaccine types (P = 0.024). ACVs contain P.69 and S1 types which are found in only 10% of recent Dutch B. pertussis isolates, implying that they do not have an optimal composition. Our findings cast a new light on the reemergence of pertussis in highly vaccinated populations and may have major implications for the long-term efficacy of both WCVs and ACVs.

Bordetella pertussis fimbriae are composed of a major subunit, Fim2 or Fim3, and the minor subunit FimD. Using immunoelectron microscopy, we provide evidence that FimD is located at the fimbrial tip. The role of FimD in colonization of the mouse respiratory tract was studied by using two fimbrial mutants: a mutant completely devoid of fimbriae (designated FimD-) and a mutant devoid of the major fimbrial subunits but still producing the minor subunit (designated FimD+). The ability of the two fimbrial mutants to colonize the nasopharynx, trachea, and lungs was compared with those of the wild type parental strain and a filamentous hemagglutinin (FHA) mutant. Of the three mutants studied, the FimD- mutant showed the greatest defect, colonizing less well in the nasopharynx, trachea, and lungs. The most pronounced defect in colonizing ability of the three mutants was observed in the trachea. However, the colonizing defect of the FHA and FimD+ mutants in the trachea was observed only during the first 3 days of infection. After 10 days, the colonization level was nearly restored to wild-type levels. The FHA and FimD+ mutants showed a slight colonization defect in the nasopharynx but no defect in the lungs. A maltose binding protein-FimD fusion protein and a peptide derived from FimD were able to bind to heparin, a member of a class of sulfated sugars which are ubiquitous in the respiratory tract. Recently it was shown (W. L. W. Hazenbos, C. A. W. Geuijen, B. M. van den Berg, F. R. Mooi, and R. van Furth, J. Infect. Dis. 171:924-929, 1995) that FimD also binds to the integrin VLA-5, and our results suggest that the binding of B. pertussis to these two molecules plays an important role in colonization of the respiratory tract of the mouse.

Bordetella pertussis fimbriae are composed of major and minor subunits, and recently it was shown that the minor fimbrial subunit binds to Vla-5, a receptor located on monocytes (W. Hazenbos, C. Geuijen, B. van den Berg, F. Mooi, and R. van Furth, J. Infect. Dis. 171:924-929, 1995). Here we present evidence that the major subunits bind to sulfated sugars, which are ubiquitous in the respiratory tract. Binding was observed to chondroitin sulfate, heparan sulfate, and dextran sulfate but not to dextran. Removal of the minor subunit from fimbriae did not significantly affect binding to sulfated sugars, indicating that the major subunit alone is sufficient for this binding. Fimbriae were also able to bind HEp-2 cells, which are known to display glycoconjugates on their surface. This binding was not dependent on the presence of the minor subunit. However, binding was dependent on the sulfation state of the glycoconjugates, since inhibition of the sulfation resulted in a significant reduction of fimbria binding. The specificity of fimbria binding was further characterized by using heparan sulfate-derived disaccharides in inhibition assays. Two disaccharides were highly effective inhibitors, and it was observed that both the degree of sulfation and the arrangement of the sulfate groups on the disaccharides were important for binding to fimbriae. B. pertussis bacteria also bound to sulfated sugars and HEp-2 cells, and analysis of B. pertussis mutants indicated that both filamentous hemagglutinin and fimbriae were required for this binding. A host protein present in the extracellular matrix, fibronectin, has binding activities similar to those of B. pertussis fimbriae, binding to both Vla-5 and sulfated sugars. Two regions in the major fimbrial subunit were identified which showed similarity with fibronectin peptides which bind to sulfated sugars. Thus, B. pertussis fimbriae exemplify molecular mimicry and may co-opt host processes by mimicking natural ligand-receptor interactions.

The nucleoside diphosphate kinase (NDPK/nm23) isoforms H1 and H2 were localized in hematopoietic tissues. Flow cytometric analysis and enzymatic assays were used to quantify the intracellular and extracellular concentrations of NDPK. Bone marrow CD34(+) progenitors contained the highest intracellular levels of both nm23-H1 and nm23-H2. Lower levels were measured in more mature bone marrow cells, whereas peripheral blood leukocytes had the lowest expression of nm23. These data suggest a function of NDPK in early hematopoiesis and a down-regulation of NDPK upon differentiation. In addition, an up-regulation of nm23 expression was observed in lymphocytes after induction of proliferation with phytohemagglutinin. Multiparameter flow cytometry demonstrated that this up-regulation occurred during the G0/G1-transition. Flow cytometric analysis also revealed a weak surface expression of nm23 on a number of hematopoietic cell lines, which was not detected on normal hematopoietic cells. Our data also demonstrated the presence of NDPK in human plasma, probably due to a limited in vivo lysis of red blood cells.

Bordetella pertussis fimbriae bind to sulfated sugars such as heparin through the major subunit Fim2. The Fim2 subunit contains two regions, designated H1 and H2, which show sequence similarity with heparin binding regions of fibronectin, and the role of these regions in heparin binding was investigated with maltose binding protein (MBP)-Fim2 fusion proteins. Deletion derivatives of MBP-Fim2 showed that both regions are important for binding to heparin. The role of H2 in heparin binding was confirmed by site-directed mutagenesis in which basic amino acids were replaced by alanine. These studies revealed that Lys-186 and Lys-187 are important for heparin binding of MBP-Fim2, whereas Arg-179 is not required. Peptides derived from H1 and H2 (pepH1 and pepH2) also showed heparin binding activity. Using a series of peptides, in each of which a different basic amino acid was substituted for alanine, we demonstrated that the structural requirements for heparin binding differ significantly among pepH1 and pepH2 peptides. A Pepscan analysis of Fim2 revealed regions outside H1 and H2 which bind heparin and showed that not only basic amino acids but also tyrosines may be important for binding to sulfated sugars. A comparison of the heparin binding regions of Fim2 with homologous regions of Fim3 and FimX, two closely related but antigenically distinct fimbrial subunits, showed that basic amino acids and tyrosines are generally conserved. The major heparin binding regions identified in Fim2 are part of epitopes recognized by human antibodies, suggesting that the heparin binding regions are exposed at the fimbrial surface and are immunodominant. Since B. pertussis fimbriae show weak serological cross-reactivity, the differences in primary structure in the heparin binding regions of Fim2, Fim3, and FimX may affect antibody binding but not heparin binding, allowing the bacteria to evade antibody-mediated immunity by switching the fimbrial gene expressed.

With DNA probes derived from the fimbrial subunit genes fim2 and fim3 of Bordetella pertussis, two homologous subunit genes of Bordetella bronchiseptica were identified and cloned. The nucleotide sequences of these genes were determined. Comparison of these nucleotide sequences with the B. pertussis fimbrial fim2 and fim3 subunit genes showed a pronounced homology. Therefore, the B. bronchiseptica genes were also designated fim2 and fim3. Expression of the two B. bronchiseptica genes was demonstrated by Western blotting (immunoblotting) with polyclonal antiserum directed against the Fim2 and Fim3 fimbrial subunit proteins of B. pertussis and by enzyme-linked immunosorbent assay with monoclonal antibodies. After growth of B. bronchiseptica in the presence of MgSO4, no expression of both fimbrial subunit genes was observed. While no fimbriae were expressed, expression of flagella was observed under these circumstances. A longer C-stretch (up to 19 cytosine residues) than the one in front of the fim2 and fim3 genes of B. pertussis is present in front of the B. bronchiseptica fimbrial genes. In adherence experiments, fimbriated (Bvg+) as well as flagellated (Bvg-) B. bronchiseptica bacteria were able to adhere to HeLa cells, whereas nonflagellated B. pertussis did not. This suggests that fimbriae as well as other factors (possibly flagella) contribute to adherence of B. bronchiseptica to eukaryotic cells.

The nucleotide sequences of the genes faeF, faeH, faeI, and faeJ encoding K88 minor fimbrial subunits were determined. Analysis of the primary structure of the gene products revealed that all four proteins are synthesized with an amino-terminal signal sequence. The molecular masses of the mature FaeF, FaeH, FaeI, and FaeJ proteins were calculated to be 15,161, 25,461, 24,804, and 25,093 Da, respectively. FaeH, FaeI, and FaeJ showed significant homology with FaeG, the major fimbrial subunit of K88 fimbriae. Mutations in the respective genes were constructed. Analysis of the mutants showed that the minor fimbrial subunits FaeF and FaeH play an essential role in the biogenesis but not in the adhesive properties of the K88 fimbriae. Mutations in faeI or faeJ had no significant effect on K88 production or adhesive capacity. Specific antisera against FaeF and FaeH were raised by immunization with hybrid Cro-LacZ-FaeF and Cro-LacZ-FaeH proteins. Immunoblotting and immunoelectron microscopy revealed that FaeF and FaeH are located in or along the K88 fimbrial structure.

Enterococcus faeciumis one of the most frequent nosocomial pathogens of hospital-acquired infections. E. faeciumhas gained resistance against most commonly available antibiotics, most notably, against ampicillin, gentamicin, and vancomycin, which renders infections difficult to treat. Many antibiotic resistance traits, in particular, vancomycin resistance, can be encoded in autonomous and extrachromosomal elements called plasmids. These sequences can be disseminated to other isolates by horizontal gene transfer and confer novel mechanisms to source specificity. In our study, we elucidated the total plasmid content, referred to as the plasmidome, of 1,644 E. faeciumisolates by using short- and long-read whole-genome technologies with the combination of a machine-learning classifier. This was fundamental to investigate the full collection of plasmid sequences present in our collection (pan-plasmidome) and to observe the potential transfer of plasmid sequences between E. faeciumhosts. We observed that E. faeciumisolates from hospitalized patients carried a larger number of plasmid sequences compared to that from other sources, and they elucidated different configurations of plasmidome populations in the hospital environment. We assessed the contribution of different genomic components and observed that plasmid sequences have the highest contribution to source specificity. Our study suggests that E. faeciumplasmids are regulated by complex ecological constraints rather than physical interaction between hosts.

Purpose: Left atrial enlargement is an early sign of left heart disease with prognostic implications in both the general population and in heart failure (HF). The importance of right atrial enlargement is less studied. Available prognostic information on echocardiographic findings is mostly derived from middle-aged patients, while a majority of heart failure patients are elderly. The aims of the present study were to test the hypothesis that right atrial size is a predictor of mortality in elderly with heart failure independent of ejection fraction and that right atrium larger than left atrium conveys even worse prognosis. Methods: Retrospectively, 289 patients above 65 years hospitalized for HF between April 2007 and April 2008, and who went through an echocardiographic exam were enrolled. Right atrial area index (RAAI) and other echocardiographic measures were examined as predictors of all-cause mortality over a follow-up of at least 56 months. Results: The mean RAAI was 12.4 ± 4.4 cm2/m2 with modest correlation to echocardiographically estimated central venous pressure and pulmonary artery pressure (Spearman’s r = 0.55 and r = 0.32 respectively and p < 0.001 for both). Univariate analysis for mortality prediction showed that RAAI had a hazard ratio (HR) of 1.07 (95% confidence interval: 1.04–1.11, p < 0.001). The RAAI remained a predictor of survival even after adjusting for age, left ventricular ejection fraction, atrial fibrillation, left ventricular mass index and left atrial volume index (HR: 1.06, 95% confidence interval: 1.02–1.10, p = 0.005). Mortality rate was 88.2 % in patients with RAA larger than left atrial area as compared with 60.1 % in those who showed an inverse relation in atrial areas (log-rank X2 =19.6; p < 0.001). Conclusions: Right atrial size is an independent predictor of mortality in elderly patients hospitalised due to HF. A right atrium larger than left atrium conveys even worse prognosis.

Eine biatriale getriggerte Elektrostimulation ist eine sichere und tendenziell effektive Methode zur Reduktion der Inzidenz postoperativen Vorhofflimmerns bei Patienten nach ACVB-Operation. Die in unserer Untersuchung nicht erlangte statistische Signifikanz im Vergleich der verschiedenen Stimulationsmodi bezüglich der Inzidenz von Vorhofflimmern liegt unseres Erachtens an der zu kleinen Fallzahl der in die Untersuchung eingeschlossenen Patienten.

Der Beginn der Wahrnehmung der intrinsischen atrialen Aktivierung über wandständige Elektroden ist von der Plazierung der Elektroden abhängig (HRA signifikant früher als Cs-Os). Die frühesten intrinsischen Wahrnehmungen rechtsatrialer Aktivität erfolgten über flottierende atriale Ringe einer VDD-Elektrode. Die myokardiale Erregungsfront erreicht die wandständigen Elektroden deutlich später. Die Registrierung eines so frühen atrialen Signals könnte zur Prävention von atrialen Arrhythmien bei zukünftigen Schrittmachersystemen Bedeutung erlangen.

Die Ergebnisse dieser experimentellen Studie zeigen, daß eine atriale Stimulation über flottierende Elektroden mit der BIMOS Konfiguration eine signifikante Reduktion der IACT, IECT, TAAT und der PD gegenüber einer konventionellen wandständigen Stimulation im HRA erreicht. Die Reduktion der Leitungszeiten und die Verkürzung der P-Wellendauer durch die BIMOS Stimulationskonfiguration könnte für zukünftige neue Schrittmachersysteme zur Prävention von Tachyarrhythmien eine große Bedeutung erlangen.

Schubert and co‐workers have performed a detailed atomic force microscopy study to establish and characterize the oxidation conditions of self‐assembled monolayers of octadecyl trichlorosilane on silicon substrates. The cover image illustrates different examples of surfaces that were structured with different patterning conditions, as reported on p. 938. The graph in the background depicts three observed oxidation regimes depending on applied voltage and oxidation time.

Essentual difficulties arise when base number in oligoguanylic blocks and location of these blocks along the polynucleotide chain need to be determined in the course of determination of the nucleotide sequences in ribonucleic acids. To overcome this difficulty it is suggested to take advantage of a recently discovered resistance of phosphodiester bond between kethoxalated G and its 3′-neighbour against T2 RNase hydrolysis 1,2. The approach is illustrated by analysis of 5S RNA from rat liver. Sequences of general formula (Gp)nXp were isolated from T2 RNase hydrolysate of 5 S RITA rapidly and quantitatively. The information obtained greatly facilitates the whole procedure of sequencing. It is expected that the method proposed would be effective for analysis of 5 S and 4 S RNA and for highmolecular weight fragments of ribosomnl and viral HIT As.