Core genome multi-locus sequence typing as an essential tool in a high-cost livestock-associated meticillin-resistant Staphylococcus aureus CC398 hospital outbreak.

BACKGROUND: Livestock-associated meticillin-resistant Staphylococcus aureus (LA-MRSA) clonal complex (CC) 398 may be transmitted and cause morbidity and mortality in hospitals. The economic cost of stopping hospital transmission of LA-MRSA CC398 is poorly described. Early detection of transmission may limit the extent of the intervention. AIM: To evaluate core genome multi-locus sequence typing (cgMLST) for detecting transmission chains and to estimate the costs for interventions to prevent further spread after discovery of hospital transmission of LA-MRSA CC398. METHODS: Five patients were involved in two episodes of transmission of LA-MRSA CC398 in a hospital. Standard interventions including MRSA screening of patients and healthcare workers were initiated. Whole genome sequences of the five isolates and 17 epidemiologically unrelated MRSA CC398 isolates from other hospitalized patients were analysed by single nucleotide polymorphism (SNP) comparisons and cgMLST. The economic costs of constraining transmission were calculated from relevant sources. FINDINGS: The five isolates suspected to be involved in hospital transmission clustered with ≤2 SNPs in the draft genome sequences with some distance to other isolates. cgMLST allocated the five isolates to the same type, which was different from all but two of the sporadic isolates. Furthermore, cgMLST separated the five transmission isolates from all other isolates. The economic costs of the outbreak interventions exceeded €11,000 per patient. CONCLUSION: LA-MRSA CC398 is transmittable in hospitals, and intervention against transmission may reach considerable costs. cgMLST is useful in surveillance of hospital transmission of LA-MRSA.

The impact of left ventricular lead position on left ventricular reverse remodelling and improvement in mechanical dyssynchrony in cardiac resynchronization therapy.

AIMS: To investigate the influence of left ventricular (LV) lead position on LV dyssynchrony in cardiac resynchronization therapy (CRT). METHODS AND RESULTS: The LV lead was prospectively targeted to the latest activated LV segment (concordant) evaluated by two-dimensional speckle tracking radial strain (ST-RS) echocardiography in 103 CRT recipients (67 ± 12 years). Mechanical dyssynchrony was assessed by anteroseptal-to-posterior (AS-P) delay and interventricular mechanical delay (IVMD). Concordant LV leads were obtained in 72 (70%) patients. Superior LV reverse remodelling (LV-RR; ≥ 15% LV end-systolic volume reduction at 6-month follow-up) was observed in the concordant LV leads compared with the discordant LV leads [51 (76%) vs. 13 (45%); P = 0.003]. Mechanical resynchronization responders (≥ 50% AS-P delay reduction at 6-month follow-up) obtained in the concordant LV leads [44 (66%)] was greater than in the discordant LV leads [10 (34%); P = 0.005]. The discordant LV leads located adjacent to the concordant LV leads (+1 segment; n = 22) and 2 segments apart (+2 segments; n = 9) were evaluated in a subgroup analysis. Mechanical resynchronization responders 6 months after CRT were as follows: in +1 segment [n = 10 (48%)] and in +2 segments (n = 0; P = 0.001). The concordant LV lead was the only independent predictor of LV-RR at 6-month follow-up (odds ratio, 4.177; P = 0.004). Independent predictors of mechanical resynchronization responders were AS-P delay (odds ratio, 1.007; P = 0.032), IVMD (odds ratio, 1.024; P = 0.038), and concordant LV lead (odds ratio, 4.691; P = 0.004). CONCLUSION: Concordant LV leads in CRT provided more responders according to both LV reverse remodelling and mechanical resynchronization.

A randomized study of haemodynamic effects and left ventricular dyssynchrony in right ventricular apical vs. high posterior septal pacing in cardiac resynchronization therapy.

AIMS: The effect on left ventricular (LV) systolic function and LV dyssynchrony by alternative right ventricular (RV) lead position in cardiac resynchronization therapy (CRT) is unclear. In the present study, RV apical (RV-A) was compared with RV high posterior septal (RV-HS) lead position in CRT. METHODS AND RESULTS: In 85 consecutive CRT patients (mean age 66 ±11 years) the RV lead placement was randomized to RV-A (n = 43) or RV-HS (n = 42). The LV lead was targeted to the latest activated LV segment (concordant LV lead), identified by two-dimensional speckle tracking radial strain (ST-RS) echocardiography. Concordant LV leads were obtained in 72%, similar in RV-A and RV-HS (79% vs. 64%; P = 0.13). Six months after CRT, no difference was found in LV reverse remodelling (reduction of LV end-systolic volume ≥15%) according to RV-A and RV-HS leads [26 (65%) vs. 25 (64%); P = 0.93]. Superior LV reverse remodelling was observed in concordant LV leads compared with discordant LV leads [41 (73%) vs. 10 (43%); P = 0.01]. At 6-month follow-up, LV reverse dyssynchrony (reduction of anteroseptal to posterior delay ≥50%) using ST-RS imaging was similar in RV-A and RV-HS [25 (63%) vs. 24 (62%); P = 0.93]. More LV reverse dyssynchrony was found in concordant LV leads vs. discordant LV leads [39 (70%) vs. 10 (43%); P = 0.03]. A concordant LV lead was an independent predictor of LV reverse remodelling (odds ratio, 3.65; P = 0.01) and LV reverse dyssynchrony (odds ratio, 4.22; P = 0.02) 6 months after CRT. CONCLUSION: RV-A and RV-HS in CRT demonstrated similar LV reverse remodelling and LV reverse dyssynchrony at 6-month follow-up. Concordant LV leads provided superior LV reverse remodelling and LV reverse dyssynchrony.

Coarse-grained molecular dynamics simulations on size effect of glassy polyethylene particles.

The size effect on mechanical properties of glassy polyethylene (PE) nanoscale particles has been investigated by extensive coarse-grained molecular dynamics simulations. The diameter of the PE particles varies in the range of 5-40 nm, we confirm that the particle's behaviour under compressive stress strongly depends on its size-the smaller the particle diameter is, the stiffer the particle behaves. The present mechanical responses of compressed particles are in good agreement with our previous experimental phenomena of micron-sized polymer particles measured by a nanoindentation-based flat punch method. Possible reasons for the size effect are discussed.

Target structure induced suppression of the ionization cross section for very low energy antiproton-hydrogen collisions.

Low energy antiprotons have been used previously to give benchmark data for theories of atomic collisions. Here we present measurements of the cross section for single, nondissociative ionization of molecular hydrogen for impact of antiprotons with kinetic energies in the range 2-11 keV, i.e., in the velocity interval of 0.3-0.65 a.u. We find a cross section which is proportional to the projectile velocity, which is quite unlike the behavior of corresponding atomic cross sections, and which has never previously been observed experimentally.

Ionization of helium and argon by very slow antiproton impact.

The total cross sections for single ionization of helium and single and double ionization of argon by antiproton impact have been measured in the kinetic energy range from 3 to 25 keV using a new technique for the creation of intense slow antiproton beams. The new data provide benchmark results for the development of advanced descriptions of atomic collisions and we show that they can be used to judge, for the first time, the validity of the many recent theories.

Unaltered neuropeptide Y (NPY)-stimulated [35S]GTPgammaS binding suggests a net increase in NPY signalling after repeated electroconvulsive seizures in mice.

Although electroconvulsive seizures (ECS) are widely used as a treatment for severe depression, the working mechanism of ECS remains unclear. Repeated ECS causes anticonvulsant effects that have been proposed to underlie the therapeutic effect of ECS, and neuropeptide Y (NPY) is a potential candidate for mediating this anticonvulsant effect. Repeated ECS results in prominent increases in NPY synthesis. In contrast, NPY-sensitive receptor binding is decreased, so it is unclear whether ECS causes a net increase in NPY signalling. Agonist-stimulated [35S]GTPgammaS binding is a method for detecting functional activation of G-protein-coupled receptors. The present study in mice examined the effects of daily ECS for 14 days on NPY-stimulated [35S]GTPgammaS functional binding and compared this with gene expression of NPY and NPY receptors as well as [125I]peptide YY (PYY) binding in hippocampus of the same animals. Significant increases in NPY mRNA and concomitant reductions in NPY-sensitive binding were found in the dentate gyrus, hippocampal CA1, and neocortex of ECS treated mice, which is consistent with previous rat data. These changes remained significant 1 week after repeated ECS. Significant increases in NPY Y1, Y2, and Y5 mRNA were found in the dentate gyrus after ECS. Surprisingly, unaltered levels of functional NPY receptor binding accompanied the decreased NPY-sensitive binding. This suggests that mechanisms coupling NPY receptor stimulation to G-protein activation could be augmented after repeated ECS. Thus increased synthesis of NPY after repeated ECS should result in a net increase in NPY signalling in spite of reduced levels of NPY-sensitive binding.

Trial of high-dose Edmonston-Zagreb measles vaccine in Guinea-Bissau: protective efficacy.

In a randomised study of 558 children in an urban African community, the protective effect of the Edmonston-Zagreb (EZ) measles vaccine given in a dose of 40,000 plaque forming units from the age of 4 months was compared with the effects of a standard dose (6000 tissue culture infectious units) of Schwarz measles vaccine given from the age of 9 months. During two years of follow-up, all 14 clinical cases of measles occurred in the Schwarz group; 10 of the children contracted measles before vaccination and 4 after measles vaccination. Thus the EZ vaccine provided significant protection against measles both before and after the usual age of vaccination. Among the children who were exposed to measles at home, those given EZ vaccine were better protected than either unvaccinated children or those given the Schwarz vaccine.

[Experience and results of an epidemiological screening study in the southern part of Guinea-Bissau]. / Erfaringer og resultater af en epidemiologisk screeningsundersøgelse i det sydlige Guinea-Bissau.

PIP: In 1984, a cross-sectional survey was carried out in Quitafine, the southernmost district of Guinea-Bissau in West Africa, as part of an ongoing health project in the area. The aim of the survey was to collect data on essential health problems in children under the age of 5 and from pregnant women to evaluate the results of certain preventive efforts. A census in 8 selected villages showed a typical age distribution for a developing county with children under age 15 comprising 50% of the population and children under age 5 comprising 20%. A total of 296 resident children (89%) were included. The high rate of participation is a ascribed to a comprehensive collaboration with the village committees, including careful preparation the day before the clinical investigation. Generally, the nutritional status of the children was not bad, although 28% demonstrated signs of mild malnutrition in the 2nd year of life. Hookworm infestation was the most frequent intestinal parasitosis. Vaccination coverage was unsatisfactorily low (53%). At a follow-up of children 2 1/2 years later, 11 had died (3.8%). Results of the survey on pregnant women were similar to those from health care centers; i.e., there was a high maternal mortality (1%). Similarly, a high stillbirth rate (3.8%) and neonatal mortality (6.9%) were found. Epidemiological surveys should be an obligatory part of health care aid projects, with the aim of generating results which would be useful in practical health care work. (author's modified)^ieng

The epidemiology of cryptosporidiosis and other intestinal parasitoses in children in southern Guinea-Bissau.

In order to determine the prevalence of Cryptosporidium and other intestinal parasites, a household sample survey of children under 5 years old was carried out during the late dry season in 8 rural villages in southern Guinea-Bissau, West Africa. Cryptosporidium oocysts were found in 10 of 270 stool samples (3.7%), using a safranin-methylene blue staining method. Of these 10 children (age range 5-16 months), all non-Muslims, 6 had diarrhoea, giving a prevalence of 12.5% in 48 children with diarrhoea, compared with 1.8% in children without diarrhoea (P less than 0.001). The ethnic group with the highest prevalence (9.2%) also kept most domestic animals, and was the only group to keep cattle. Giardia lamblia was found in 16 children, and the overall prevalences of other enteric parasites were: hookworm, 21.7%; Strongyloides stercoralis, 7.4%; Ascaris lumbricoides, 6.9%; Trichuris trichiura, 4.4%; Entamoeba histolytica, 1.5%; and Taenia sp., 0.5%. The prevalence of cryptosporidiosis was highest in the age group 7-12 months, while for the other parasites it was highest in the oldest children. The prevalence of hookworm was highest (c. 50%) in the southernmost villages. No significant relationship was found between hookworm infection and anaemia.