Unravelling the complex interplay between antibiotic consumption and adaptive changes in methicillin-resistant Staphylococcus aureus

Funding: This study was supported by internal funding.Objectives This study aims to elucidate the genomic dynamics driving the emergence of antimicrobial resistance (AMR), with a specific focus on the interplay between AMR and antimicrobial usage. Methods We conducted a comprehensive analysis using a ST239 methicillin-resistant Staphylococcus aureus (MRSA) dataset over a continuous 12-year period from a single hospital. Genomic analyses were performed tracking the changes in MRSA populations, particularly the emergence of reduced vancomycin susceptibility, and assessing the impact of glycopeptide use on these emergence events. Results Our findings reveal a significant correlation between hospital glycopeptide usage and the selection of MRSA strains with reduced vancomycin susceptibility. Genomic analyses provided insights into the molecular mechanisms driving resistance emergence, including the slowing of the molecular clock rate in response to heightened antimicrobial consumption. Conclusions In conclusion, this study the highlights the complex dynamics between AMR and antimicrobial use at the hospital level. The observed correlation between antimicrobial consumption and the development of less susceptible MRSA strains underscores the importance of antimicrobial stewardship programmes and the establishment of optimal consumption thresholds for mitigating AMR effectively.Peer reviewe

Cluster ionization via two-plasmon excitation

We calculate the two-photon ionization of clusters for photon energies near the surface plasmon resonance. The results are expressed in terms of the ionization rate of a double plasmon excitation, which is calculated perturbatively. For the conditions of the experiment by Schlipper et al., we find an ionization rate of the order of 0.05-0.10 fs^(-1). This rate is used to determine the ionization probability in an external field in terms of the number of photons absorbed and the duration of the field. The probability also depends on the damping rate of the surface plasmon. Agreement with experiment can only be achieved if the plasmon damping is considerably smaller than its observed width in the room-temperature single-photon absorption spectrum.Comment: 17 pages and 6 PostScript figure

Smoking Patterns and Receipt of Cessation Services Among Pregnant Women in Argentina and Uruguay

Introduction: The 5A’s (Ask, Advise, Assess, Assist, and Arrange) strategy, a best-practice approach for cessation counseling, has been widely implemented in high-income countries for pregnant women; however, no studies have evaluated implementation in middle-income countries. The study objectives were to assess smoking patterns and receipt of 5A’s among pregnant women in Buenos Aires, Argentina and Montevideo, Uruguay. Methods: Data were collected through administered questionnaires to women at delivery hospitalizations during October 2011–May 2012. Eligible women attended one of 12 maternity hospitals or 21 associated prenatal care clinics. The questionnaire included demographic data, tobacco use/cessation behaviors, and receipt of the 5A’s. Self-reported cessation was verified with saliva cotinine. Results: Overall, of 3400 pregnant women, 32.8% smoked at the beginning of pregnancy; 11.9% quit upon learning they were pregnant or later during pregnancy, and 20.9% smoked throughout pregnancy. Smoking prevalence varied by country with 16.1% and 26.7% who smoked throughout pregnancy in Argentina and Uruguay, respectively. Among pregnant smokers in Argentina, 23.8% reported that a provider asked them about smoking at more than one prenatal care visit; 18.5% were advised to quit; 5.3% were assessed for readiness to quit, 4.7% were provided assistance, and 0.7% reported follow-up was arranged. In Uruguay, those percentages were 36.3%, 27.9%, 5.4%, 5.6%, and 0.2%, respectively. Conclusions: Approximately, one in six pregnant women smoked throughout pregnancy in Buenos Aires and one in four in Montevideo. However, a low percentage of smokers received any cessation assistance in both countries. Healthcare providers are not fully implementing the recommended 5A’s intervention to help pregnant women quit smoking.Fil: Berrueta, Amanda Mabel. Instituto de Efectividad Clínica y Sanitaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Morello, Paola. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Alemán, Alicia. Unidad de Investigación Clínica y Epidemiológica Montevideo; UruguayFil: Tong, Van T.. Centers for Disease Control and Prevention; Estados UnidosFil: Johnson, Carolyn. Tulane School of Public Health and Tropical Medicine; Estados UnidosFil: Dietz, Patricia M.. Centers for Disease Control and Prevention; Estados UnidosFil: Farr, Sherry L.. Centers for Disease Control and Prevention; Estados UnidosFil: Mazzoni, Agustina. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Colomar, Mercedes. Unidad de Investigación Clínica y Epidemiológica Montevideo; UruguayFil: Ciganda, Alvaro. Unidad de Investigación Clínica y Epidemiológica Montevideo; UruguayFil: Llambi, Laura. Unidad de Investigación Clínica y Epidemiológica Montevideo; UruguayFil: Becú, Ana. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Gibbons, Luz. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Smith, Ruben A.. Centers for Disease Control and Prevention; Estados UnidosFil: Buekens, Pierre. Tulane School of Public Health and Tropical Medicine; Estados UnidosFil: Belizan, Jose. Instituto de Efectividad Clínica y Sanitaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Althabe, Fernando. Instituto de Efectividad Clínica y Sanitaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Hierarchical model for the scale-dependent velocity of seismic waves

Elastic waves of short wavelength propagating through the upper layer of the Earth appear to move faster at large separations of source and receiver than at short separations. This scale dependent velocity is a manifestation of Fermat's principle of least time in a medium with random velocity fluctuations. Existing perturbation theories predict a linear increase of the velocity shift with increasing separation, and cannot describe the saturation of the velocity shift at large separations that is seen in computer simulations. Here we show that this long-standing problem in seismology can be solved using a model developed originally in the context of polymer physics. We find that the saturation velocity scales with the four-third power of the root-mean-square amplitude of the velocity fluctuations, in good agreement with the computer simulations.Comment: 7 pages including 3 figure

Genetic Evidence of Functional Ficolin-2 Haplotype as Susceptibility Factor in Cutaneous Leishmaniasis

Background: Ficolin-2 coded by FCN2 gene is a soluble serum protein that plays an important role in innate immunity. In this study, we analyzed five functional polymorphisms of the FCN2 gene for their possible association with cutaneous leishmaniasis. Methods: Initially we screened 40 Syrian Arabs for the entire FCN2 gene. We investigated the contribution of FCN2 functional variants in 226 patients with cutaneous leishmaniasis and 286 healthy controls from Syria. Polymorphisms in the promoter regions (2986G/A, 2602G/A, 24A/G) of the FCN2 gene were assessed by TaqMan real time PCR, whereas polymorphisms in exon8 (+6359C/T and +6424G/T) were assessed by DNA sequencing. We also measured serum ficolin-2 levels in 70 control Syrian Arabs and correlated the serum concentrations to FCN2 genotypes and haplotypes respectively. Results: Nine new FCN2 variants including two with non synonymous substitutions in exon6 and exon8 were observed. The homozygous genotypes +6424T/T were distributed more in controls and none in patients (P = 0.04). The AGACG haplotype were observed more in patients than in controls (OR = 2.0, 95%CI 1.2–3.4, P = 0.006). The serum ficolin-2 levels were significantly distributed among the reconstructed ficolin-2 haplotypes (P,0.008) and the haplotype AGACG was observed with higher ficolin-2 levels in 70 control individuals. Conclusion: Our results demonstrate a significant association of FCN2 AGACG haplotype with cutaneous leishmaniasis in a Syrian Arab population. These first results provide a basis for a future study that could confirm or disprove possibl

Initial-state dependence in time-dependent density functional theory

Time-dependent density functionals in principle depend on the initial state of the system, but this is ignored in functional approximations presently in use. For one electron it is shown there is no initial-state dependence: for any density, only one initial state produces a well-behaved potential. For two non-interacting electrons with the same spin in one-dimension, an initial potential that makes an alternative initial wavefunction evolve with the same density and current as a ground state is calculated. This potential is well-behaved and can be made arbitrarily different from the original potential

Differential Photoelectron Holography: A New Approach for Three-Dimensional Atomic Imaging

We propose differential holography as a method to overcome the long-standing forward-scattering problem in photoelectron holography and related techniques for the three-dimensional imaging of atoms. Atomic images reconstructed from experimental and theoretical Cu 3p holograms from Cu(001) demonstrate that this method suppresses strong forward-scattering effects so as to yield more accurate three-dimensional images of side- and back-scattering atoms.Comment: revtex, 4 pages, 2 figure

Fully Automatic Expression-Invariant Face Correspondence

We consider the problem of computing accurate point-to-point correspondences among a set of human face scans with varying expressions. Our fully automatic approach does not require any manually placed markers on the scan. Instead, the approach learns the locations of a set of landmarks present in a database and uses this knowledge to automatically predict the locations of these landmarks on a newly available scan. The predicted landmarks are then used to compute point-to-point correspondences between a template model and the newly available scan. To accurately fit the expression of the template to the expression of the scan, we use as template a blendshape model. Our algorithm was tested on a database of human faces of different ethnic groups with strongly varying expressions. Experimental results show that the obtained point-to-point correspondence is both highly accurate and consistent for most of the tested 3D face models

The Expression of Epac2 and GluA3 in an Alzheimer's Disease Experimental Model and Postmortem Patient Samples

Alzheimer's disease (AD) is one of the most prevalent neurodegenerative diseases, characterized by amyloid beta (Aβ) and hyperphosphorylated tau accumulation in the brain. Recent studies indicated that memory retrieval, rather than memory formation, was impaired in the early stage of AD. Our previous study reported that pharmacological activation of hippocampal Epac2 promoted memory retrieval in C57BL/6J mice. A recent study suggested that pharmacological inhibition of Epac2 prevented synaptic potentiation mediated by GluA3-containing AMPARs. In this study, we aimed to investigate proteins associated with Epac2-mediated memory in hippocampal postmortem samples of AD patients and healthy controls compared with the experimental AD model J20 and wild-type mice. Epac2 and phospho-Akt were downregulated in AD patients and J20 mice, while Epac1 and phospho-ERK1/2 were not altered. GluA3 was reduced in J20 mice and tended to decrease in AD patients. PSD95 tended to decrease in AD patients and J20. Interestingly, AKAP5 was increased in AD patients but not in J20 mice, implicating its role in tau phosphorylation. Our study points to the downregulation of hippocampal expression of proteins associated with Epac2 in AD. </p