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The objective of this study was to determine the serotype distribution and antibiotic resistance of invasive pneumococcal disease (IPD) strains in children from Lima, Peru, before and after the introduction of the 7-valent pneumococcal conjugate vaccine (PCV7), which was introduced in the national immunisation program on 2009. We conducted a prospective, multicentre, passive surveillance IPD study during 2006–2008 and 2009–2011, before and right after the introduction of PCV7 in Peru. The study was performed in 11 hospitals and five private laboratories in Lima, Peru, in patients <18 years old, with sterile site cultures yielding Streptococcus pneumoniae. In total 159 S. pneumoniae isolates were recovered. There was a decrease in the incidence of IPD in children <2 years old after the introduction of PCV7 (18.4/100 000 vs. 5.1/100 000, P = 0.004). Meningitis cases decreased significantly in the second period (P = 0.036) as well as the overall case fatality rate (P = 0.025), including a decreased case fatality rate of pneumonia (16.3% to 0%, P = 0.04). PCV7 serotypes showed a downward trend. Vaccine-preventable serotypes caused 78.9% of IPD cases, mainly 14, 6B, 5, 19F and 23F. A non-significant increase in erythromycin resistance was reported. Our findings suggest that the introduction of PCV7 led to a significant decrease of IPD in children under 2 years old and in the overall case fatality rate.
Fetal growth restriction (FGR) and preterm birth are frequent co-morbidities, both are independent risks for brain injury. However, few studies have examined the mechanisms by which preterm FGR increases the risk of adverse neurological outcomes. We aimed to determine the effects of prematurity and mechanical ventilation (VENT) on the brain of FGR and appropriately grown (AG, control) lambs. We hypothesized that FGR preterm lambs are more vulnerable to ventilation-induced acute brain injury. FGR was surgically induced in fetal sheep (0.7 gestation) by ligation of a single umbilical artery. After 4 weeks, preterm lambs were euthanized at delivery or delivered and ventilated for 2 h before euthanasia. Brains and cerebrospinal fluid (CSF) were collected for analysis of molecular and structural indices of early brain injury. FGRVENT lambs had increased oxidative cell damage and brain injury marker S100B levels compared with all other groups. Mechanical ventilation increased inflammatory marker IL-8 within the brain of FGRVENT and AGVENT lambs. Abnormalities in the neurovascular unit and increased blood–brain barrier permeability were observed in FGRVENT lambs, as well as an altered density of vascular tight junctions markers. FGR and AG preterm lambs have different responses to acute injurious mechanical ventilation, changes which appear to have been developmentally programmed in utero.
Background: The influence of psychotherapy on neurocognition in post-traumatic stress disorder (PTSD) has not been examined methodically. This is despite evidence that pre-treatment learning and memory has been associated with treatment success and that executive function theories emphasize weak executive functions (especially inhibition/switching) are associated with PTSD. Objectives: To determine (1) if higher pre-treatment learning/memory, inhibition/switching, or both predict treatment success; and (2) if treatment success is associated with specific improvement in inhibition/switching and not learning/memory or working memory, another aspect of executive function. Methods: Pre-treatment neurocognition and neurocognitive changes (inhibition/switching, learning/memory, working memory) were examined in female veterans with PTSD. They were evaluated before and after 16-weeks of group psychotherapy for PTSD that included three counterbalanced modules (cognitive restructuring therapy, exposure therapy, skills training) with fidelity checks for therapist adherence. Results: Only pre-treatment learning/memory predicted better treatment outcome. Treatment success was associated with improvement in inhibition/switching only, even after controlling for mild traumatic brain injury, and changes in depressive symptoms, working memory, and learning/memory. Conclusions: Our finding that learning/memory predicted treatment success is consistent with previous studies. We extended these studies by showing that the effect was restricted to learning/memory, which is contrary to the executive function theory of PTSD. In contrast, the fact that only inhibition/switching significantly improved with better treatment success is consistent with its potential importance in maintaining PTSD symptoms. Future research should determine whether inhibition/switching abilities are a risk for development and maintenance of PTSD or whether such abilities have a broader reciprocal relationship with PTSD symptom change. (JINS, 2016, 22, 643–651)
A similarity solution of the boundary layer equations for a wall jet on a heated horizontal surface at constant temperature taking into account the coupling of the temperature and velocity fields by buoyancy is described. This similarity solution exists for any value of
, characterizing this coupling between natural and forced convection over the horizontal plate, where
is a Grashof number and
is a Reynolds number, provided that the plate temperature is higher than the ambient temperature (
, say). Two main qualitative differences are found in the flow structure in relation to the well-known Glauert’s similarity solution for a wall jet without natural convection effects (i.e. when
): the first is that the similarity variable and structure of the horizontal velocity and temperature have the same functional form for both a radially spreading jet and a two-dimensional jet; the second is that the maximum of the horizontal velocity increases as the jet spreads over the surface, instead of decreasing like in Glauert’s solution, as the radial or horizontal distance to the power
. To check this similarity solution we solve numerically the boundary layer equations for the particular case of a jet with constant velocity and temperature emerging from a slot of height
(in the radially spreading case). An approximate, analytical similarity solution near the jet exit is also found that helps to start the numerical integration. Far from the jet exit the numerical solution tends to the similarity solution for any set of values of the non-dimensional parameters governing the problem, provided that the plate is heated (
). No similarity solution is found numerically for the case of a cooled plate (
Glauert’s similarity solution is recovered.
Objectives: The aim of this study was to explore the relationship between cognitive and white matter deterioration in a group of participants with spinocerebellar ataxia type 2 (SCA2). Methods: Fourteen genetically confirmed participants with SCA2 and 14 aged-matched controls participated in the study. Diffusion tensor imaging tract-based spatial statistics were performed to analyze structural white matter integrity. Significant group differences in the mean diffusivity were correlated with SCA2 cognitive deficits. Results: Our analysis revealed higher mean diffusivity in the SCA2 group in cerebellar white matter, medial lemniscus, and middle cerebellar peduncle, among other regions. Cognitive scores correlated with white matter mean diffusivity in the parahippocampal area, inferior frontal and supramarginal gyri and the stria terminalis. Conclusions: Our findings show significant correlations between white matter microstructural damage in key areas affected in SCA2 and cognitive deficits. These findings result in a more comprehensive understanding of the effect of the neurodegenerative process in people with SCA2. (JINS, 2016, 22, 486–491)
It has been reported that the addition of liquid rubbers, like poly(dimethylsiloxane) (PDMS), to epoxy resins alter the final morphology, increase the toughness and influence the curing kinetics. Due to immiscibility, there is phase separation of the elastomeric phase during curing giving rise to microdomains embedded in the epoxic matrix. The resultant heterogeneous morphology obtained after the reaction controls to an important extent the properties of the epoxy composite. Here we report a method to obtain well-dispersed rubber nanodomains of silyl-diglycidyl ether terminated polydimethyl siloxane (PDMS-DGE) in diglycidyl ether of bisphenol-A (DGEBA) epoxy by using a prepolymerization step. Light scattering and optical microscopy showed that initial mixing of pre-polymerized rubber produced phase separation with micron-scale droplet formation. However, as the curing reaction proceeded, the rubber domains decreased below optical resolution, light scattering intensity reached a maximum and then decreased. Finally, rubber nanodomains of about 100 nm size were formed at the end of curing reaction, as revealed by transmission electron microscopy (TEM). The pre-polymerization step induced a two-fold increase in gel time, tgel, due to lesser active groups available for reaction. Strikingly, tensile modulus and toughness increased, suggesting rubber-epoxy interaction. The final nanocomposite also exhibited higher thermal stability and char formation.
Outbreaks of soft tissue or skin infection due to non-tuberculous mycobacteria are reported frequently in scientific journals but in general the infection source in these outbreaks remains unknown. In Venezuela, in two distinct outbreaks, one after breast augmentation surgery and another after hydrolipoclasy therapy, 16 patients contracted a soft tissue infection due to Mycobacterium abscessus subsp. abscessus. Searching for the possible environmental infection sources in these outbreaks, initially the tap water (in the hydrolipoclasy therapy outbreak) and a surgical skin marker (in the breast implant surgery outbreak), were identified as the infection sources. Molecular typing of the strains with a variable number tandem repeat typing assay confirmed the tap water as the infection source but the molecular typing technique excluded the skin marker. We discuss the results and make a call for the implementation of stringent hygiene and disinfection guidelines for cosmetic procedures in Venezuela.
The histone chaperone SET/TAF-Iβ is implicated in processes of chromatin remodelling and gene expression regulation. It has been associated with the control of developmental processes, but little is known about its function in helminth parasites. In Mesocestoides corti, a partial cDNA sequence related to SET/TAF-Iβ was isolated in a screening for genes differentially expressed in larvae (tetrathyridia) and adult worms. Here, the full-length coding sequence of the M. corti SET/TAF-Iβ gene was analysed and the encoded protein (McSET/TAF) was compared with orthologous sequences, showing that McSET/TAF can be regarded as a SET/TAF-Iβ family member, with a typical nucleosome-assembly protein (NAP) domain and an acidic tail. The expression patterns of the McSET/TAF gene and protein were investigated during the strobilation process by RT-qPCR, using a set of five reference genes, and by immunoblot and immunofluorescence, using monospecific polyclonal antibodies. A gradual increase in McSET/TAF transcripts and McSET/TAF protein was observed upon development induction by trypsin, demonstrating McSET/TAF differential expression during strobilation. These results provided the first evidence for the involvement of a protein from the NAP family of epigenetic effectors in the regulation of cestode development.
ZnO was grown by Chemical Bath Deposition technique activated by microwaves (CBD-AμW) on corning glass substrates. The ZnO structural and optical properties are studied as a function of the urea concentration in the growth solution. ZnO chemical stoichiometry was determined by Energy-dispersive X-ray spectroscopy (EDS). The XRD analysis and Raman scattering reveal that ZnO deposited thin films showed hexagonal polycrystalline phase wurtzite type. The Raman spectra present four main peaks associated to the modes E2high, (E2high-E2low), E2low and an unidentified vibrational band observed at 444, 338, 104 and 78 cm-1. The E2low mode involves mainly Zn atoms motion in the unit cell and the E2high mode is associated to oxygen motion. The observed emission peaks in the room temperature photoluminescence spectra are associated at vacancies of zinc and oxygen in the lattice.
The study of corrosion behavior of polyurethane/nanohydroxyapatite hybrid coating in aerated Hank solution at 25 °C by Potentiodinamic and Electrochemical Impedance techniques was realized. The nanohydroxyapatite (nHA) powders were synthesized by ultrasonic assisted co-precipitation wet chemical method and then mixed with pure polyurethane (PU) during the polymerization. Results were supported by SEM morphologic characterization. Results showed that good corrosion resistance of hybrid coating, showing small corrosion product layer formation. Corrosion mechanisms are affected by an increasing of polarization resistance, promoting decreasing in the corrosion rates. Diffusion of ionic species was the governing mechanism in the corrosion behavior of polyurethane/nanohydroxyapatite hybrid coating.