β-Lactam Effects on Mixed Cultures of Common Respiratory Isolates as an Approach to Treatment Effects on Nasopharyngeal Bacterial Population Dynamics

BACKGROUND: Streptococcus pneumoniae, Streptococcus pyogenes and Haemophilus influenzae are bacteria present in the nasopharynx as part of normal flora. The ecological equilibrium in the nasopharynx can be disrupted by the presence of antibiotics. METHODOLOGY/PRINCIPAL FINDINGS: A computerized two-compartment pharmacodynamic model was used to explore beta-lactam effects on the evolution over time of a bacterial load containing common pharyngeal isolates by simulating free serum concentrations obtained with amoxicillin (AMX) 875 mg tid, amoxicillin/clavulanic acid (AMC) 875/125 mg tid and cefditoren (CDN) 400 mg bid regimens over 24 h. Strains and MICs (microg/ml) of AMX, AMC and CDN were: S. pyogenes (0.03, 0.03 and 0.015), S. pneumoniae (2, 2 and 0.25), a beta-lactamase positive H. influenzae (BL(+); >16, 2 and 0.06) and a beta-lactamase positive AMC-resistant H. influenzae (BLPACR, >16, 8 and 0.06). Mixture of identical 1:1:1:1 volumes of each bacterial suspension were prepared yielding an inocula of approximately 4 x 10(6) cfu/ml. Antibiotic concentrations were measured both in bacterial and in bacteria-free antibiotic simulations. beta-lactamase production decreased AMX concentrations and fT(>MIC) against S. pneumoniae (from 43.2% to 17.7%) or S. pyogenes (from 99.9% to 24.9%), and eradication was precluded. The presence of clavulanic acid countered this effect of co-pathogenicity, and S. pyogenes (but not BL(+) and S. pneumoniae) was eradicated. Resistance of CDN to TEM beta-lactamase avoided this co-pathogenicity effect, and CDN eradicated S. pyogenes and H. influenzae strains (fT(>MIC) >58%), and reduced in 94% S. pneumoniae counts (fT(>MIC) approximately 25%). CONCLUSIONS/SIGNIFICANCE: Co-pathogenicity seems to be gradual since clavulanic acid countered this effect for strains very susceptible to AMX as S. pyogenes but not for strains with AMX MIC values in the limit of susceptibility as S. pneumoniae. There is a potential therapeutic advantage for beta-lactamase resistant cephalosporins with high activity against streptococci

Update on the Combined Analysis of Muon Measurements from Nine Air Shower Experiments

Over the last two decades, various experiments have measured muon densities in extensive air showers over several orders of magnitude in primary energy. While some experiments observed differences in the muon densities between simulated and experimentally measured air showers, others reported no discrepancies. We will present an update of the meta-analysis of muon measurements from nine air shower experiments, covering shower energies between a few PeV and tens of EeV and muon threshold energies from a few 100 MeV to about 10GeV. In order to compare measurements from different experiments, their energy scale was cross-calibrated and the experimental data has been compared using a universal reference scale based on air shower simulations. Above 10 PeV, we find a muon excess with respect to simulations for all hadronic interaction models, which is increasing with shower energy. For EPOS-LHC and QGSJet-II.04 the significance of the slope of the increase is analyzed in detail under different assumptions of the individual experimental uncertainties

Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications

Superparamagnetic iron oxide nanoparticles can providemultiple benefits for biomedical applications in aqueous environments such asmagnetic separation or magnetic resonance imaging. To increase the colloidal stability and allow subsequent reactions, the introduction of hydrophilic functional groups onto the particles’ surface is essential. During this process, the original coating is exchanged by preferably covalently bonded ligands such as trialkoxysilanes. The duration of the silane exchange reaction, which commonly takes more than 24 h, is an important drawback for this approach. In this paper, we present a novel method, which introduces ultrasonication as an energy source to dramatically accelerate this process, resulting in high-quality waterdispersible nanoparticles around 10 nmin size. To prove the generic character, different functional groups were introduced on the surface including polyethylene glycol chains, carboxylic acid, amine, and thiol groups. Their colloidal stability in various aqueous buffer solutions as well as human plasma and serum was investigated to allow implementation in biomedical and sensing applications.status: publishe

Search for Spatial Correlations of Neutrinos with Ultra-high-energy Cosmic Rays

For several decades, the origin of ultra-high-energy cosmic rays (UHECRs) has been an unsolved question of high-energy astrophysics. One approach for solving this puzzle is to correlate UHECRs with high-energy neutrinos, since neutrinos are a direct probe of hadronic interactions of cosmic rays and are not deflected by magnetic fields. In this paper, we present three different approaches for correlating the arrival directions of neutrinos with the arrival directions of UHECRs. The neutrino data are provided by the IceCube Neutrino Observatory and ANTARES, while the UHECR data with energies above ∼50 EeV are provided by the Pierre Auger Observatory and the Telescope Array. All experiments provide increased statistics and improved reconstructions with respect to our previous results reported in 2015. The first analysis uses a high-statistics neutrino sample optimized for point-source searches to search for excesses of neutrino clustering in the vicinity of UHECR directions. The second analysis searches for an excess of UHECRs in the direction of the highest-energy neutrinos. The third analysis searches for an excess of pairs of UHECRs and highest-energy neutrinos on different angular scales. None of the analyses have found a significant excess, and previously reported overfluctuations are reduced in significance. Based on these results, we further constrain the neutrino flux spatially correlated with UHECRs

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Adaptación de la Iowa Infant Feeding Attitude Scale en población mexicana

INTRODUCCIÓN: la leche materna es el alimento ideal del neonato. Sin embargo, la frecuencia de la lactancia materna en México ha declinado en la última década hasta 14.4%. Una manera de enfrentar este problema es identificar las actitudes maternas hacia la lactancia, ya que es un factor modificable. La Escala de Actitudes hacia la Alimentación Infantil de Iowa (IIFAS) es utilizada para lograr este objetivo, aunque no se ha validado en México. OBJETIVO: adaptar la escala de actitudes hacia la alimentación infantil en México. MATERIALES Y MÉTODOS: estudio transversal con traducción inversa y adaptación cultural, así como consenso entre expertos para la redacción y equivalencia conceptual de los ítems de la escala IIFAS al español, para determinar su validez y fiabilidad. RESULTADOS: la escala adaptada se aplicó a 385 mujeres grávidas, el 16.3% mostró actitud positiva hacia la lactancia materna. Se determinó la fiabilidad del Instrumento (α de Cronbach 0.65), así como la validez de constructo con Análisis Factorial Exploratorio. CONCLUSIONES: la escala de actitudes hacia la alimentación infantil IIFAS versión español (México) puede considerarse válida y confiable para su uso en nuestro medio

Adaptación de la Iowa Infant Feeding Attitude Scale en población mexicana

INTRODUCCIÓN: la leche materna es el alimento ideal del neonato. Sin embargo, la frecuencia de la lactancia materna en México ha declinado en la última década hasta 14.4%. Una manera de enfrentar este problema es identificar las actitudes maternas hacia la lactancia, ya que es un factor modificable. La Escala de Actitudes hacia la Alimentación Infantil de Iowa (IIFAS) es utilizada para lograr este objetivo, aunque no se ha validado en México. OBJETIVO: adaptar la escala de actitudes hacia la alimentación infantil en México. MATERIALES Y MÉTODOS: estudio transversal con traducción inversa y adaptación cultural, así como consenso entre expertos para la redacción y equivalencia conceptual de los ítems de la escala IIFAS al español, para determinar su validez y fiabilidad. RESULTADOS: la escala adaptada se aplicó a 385 mujeres grávidas, el 16.3% mostró actitud positiva hacia la lactancia materna. Se determinó la fiabilidad del Instrumento (α de Cronbach 0.65), así como la validez de constructo con Análisis Factorial Exploratorio. CONCLUSIONES: la escala de actitudes hacia la alimentación infantil IIFAS versión español (México) puede considerarse válida y confiable para su uso en nuestro medio

Prevalence of type 2 diabetes mellitus and factors partners in the geriatric population in a general hospital Northern Mexico [Prevalencia de diabetes mellitus de tipo 2 y factores asociados en la población geriátrica de un hospital general del norte de México]

There are few reports on the impact of diabetes in the geriatric population. Objective: To determine the prevalence of diabetes in the geriatric population in a hospital in Northeast Mexico. Design: A cross-sectional study and a probabilistic sampling were made. The files of outpatients of the geriatrics department in a General Hospital in Monterrey, Mexico, were examined. The information obtained from these files was related to the patient's personal pathological and non-pathological background, besides a full geriatric evaluation. Results: A total of 171 files were examined, out of which 97 (56.7%) belonged to females and 74 (43.3%) to males. The mean age was 78 +/- 6.9 years. Diabetes was found in 76 patients (44%), major depression was found in 85 patients (50%), with the latter being more common in diabetic patients (p = 0.002). It was also found that diabetic patients take more drugs during their disease. Adjusting for age, gender, and academic level, cognitive impairment was found in 110 patients (64.3%). Conclusions: Diabetes mellitus is more frequent in the geriatric population and it uses more resources