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Clinical Enterobacteriacae isolates with a colistin minimum inhibitory concentration (MIC) ≥4 mg/L from a United States hospital were screened for the mcr-1 gene using real-time polymerase chain reaction (RT-PCR) and confirmed by whole-genome sequencing. Four colistin-resistant Escherichia coli isolates contained mcr-1. Two isolates belonged to the same sequence type (ST-632). All subjects had prior international travel and antimicrobial exposure.
This paper reports the molecular organization and mechanical properties of electrospun, post-drawn polyacrylonitrile (PAN) nanofibers. Without post-drawing, the polymer chain was kinked and oriented in hexagonal crystalline structures. Immediate post-drawing in the semi-solid state disrupted the crystal structures and chain kink at maximum draw ratio. Structural re-orientation at maximum draw resulted in a 500% increase in Young's modulus and a 100% increase in ultimate tensile strength. By applying post-drawing to electrospinning it may be possible to obtain PAN fibers and PAN-derived carbon fibers with enhanced mechanical properties compared to available fabrication technologies.
Studies examining associations between fetal serotonin reuptake inhibitor (SRI) exposure and child autism spectrum disorder (ASD) diagnoses or delayed language remain mixed and rarely prospectively follow children or employ gold-standard assessments. We prospectively followed a cohort of mother–child dyads from pregnancy through early elementary school (N = 178), and obtained maternal and alternate–caregiver ratings of behaviors related to ASD (N = 137), as well as direct, gold-standard assessments of child ASD symptoms and pragmatic language among dyads who experienced prenatal depression and either took SRIs or were medication free during pregnancy (N = 44). Prenatal SRI exposure was related to maternal ratings of ASD-related behaviors (β = 0.24 95% confidence interval; CI [0.07, 0.48]), and, among boys, alternative caregiver ratings (males-only β = 0.28 95% CI [0.02, 0.55], females-only β = −0.21 95% CI [–0.63, 0.08]). However, results of our direct assessments suggest an association between SRI exposure and reduced pragmatic language scores (β = –0.27, 95% CI [–0.53, –0.01], but not ASD (Autism Diagnostic Observation Schedule β = 0.14 95% CI [–0.15, 0.41]; Social Responsiveness Scale β = 0.08 95% CI [–0.25, 0.40]). These discrepancies point to issues regarding how ASD is assessed, and the possibility that SRIs may be more strongly associated with language or other broader behaviors that coincide with ASD. Larger prospective studies that incorporate thorough, gold-standard assessments of ASD, language, and other ASD-related behaviors are needed.
Herein we describe the use of a new DNAzyme/graphene hybrid material as a biointerfaced sensing platform for optical detection of pathogenic bacteria. The hybrid consists of a colloidal graphene nanomaterial and an Escherichia coli-activated RNA-cleaving DNAzyme and is prepared via non-covalent self-assembly of the DNAzyme onto the graphene surface. Exposure of the hybrid material to E. coli-containing samples results in the release of the DNAzyme, followed by the cleavage-mediated production of a fluorescent signal. Given that specific RNA-cleaving DNAzymes can be created for diverse bacterial pathogens, direct interfacing of graphene materials with such DNAzymes represents a general and attractive approach for real-time, sensitive, and highly selective detection of pathogenic bacteria.
A novel, alloy-agnostic, nanofunctionalization process has been utilized to produce metal matrix composites (MMCs) via additive manufacturing, providing new geometric freedom for MMC design. MMCs were produced with the addition of tungsten carbide nanoparticles to commercially available AlSi10Mg alloy powder. Tungsten carbide was chosen due to the potential for coherent crystallographic phases that were identified utilizing a lattice-matching approach to promote wetting and increase dislocation interactions. Structures were produced with evenly distributed strengthening phases leading to tensile strengths >385 MPa and a 50% decrease in wear rate over the commercially available AlSi10Mg alloy at only 1 vol% loading of tungsten carbide.
A growing number of research studies have examined the intradyadic coregulation (or attunement) of hypothalamus–pituitary–adrenal axis functioning in mothers and their children. However, it is unclear how early this coregulation may be present in dyads at clinical high risk and whether certain factors, such as maternal depression or positive parenting, are associated with the strength of this coregulation. The present study examined cortisol attunement within mother–infant dyads in a high-risk sample of 233 mothers who received treatment for psychiatric illness during pregnancy and whose infants were 6 months old at the study visit. Results showed that maternal and infant cortisol covaried across four time points that included a stressor paradigm and a mother–infant interaction task. Greater maternal positive affect, but not depression, predicted stronger cortisol attunement. In addition, infants’ cortisol level following separation from the mother predicted mothers’ cortisol level at the next time point. Mothers’ cortisol level following the separation and the laboratory stress paradigm predicted infants’ cortisol levels at each successive time point, over and above infants’ own cortisol at the previous time point. These findings suggest that maternal and infant cortisol levels influence one another in a bidirectional fashion that may be temporally and context dependent.
Patterns of dental service use can be described using a range of approaches including measures related to first dental visit, usual dental visit pattern, and the most recent dental visit. First dental visit is considered important as it represents first contact with the dental system. The usual dental visit pattern of children is also of interest as it can reflect long-term attendance patterns. The most recent dental visit is considered important as it reflects current health behaviour.
In this chapter, measures related to first dental visit will be presented for: first making a dental visit before the age of 5 years, having a check-up as the reason for the first dental visit, and reporting having never made a dental visit. Information will also be presented related to usual dental visiting using the measure of irregular usual visit pattern. For the most recent dental visit: making a dental visit within the last 12 months, having a check-up as the reason for last dental visit, attending a private dental clinic at the last dental visit, whether parents or guardians attended with the child at their last dental visit, and rating of the last dental visit by the parent/guardian.
Frequency of dental visits and the reason for dental visits are key aspects related to access to dental care (Roberts-Thomson et al. 1995). Making a recent dental visit is indicative of access to the dental care system while visiting for the reason of a check-up is considered more likely to be associated with better health outcomes than visiting for a dental problem such as relief of pain (Crocombe et al. 2012). Hence, the dental profession tends to advocate a visit pattern of attending for annual dental check-ups to access preventive dental care or allow diagnosis of dental problems at an early stage, which can facilitate treatment before the disease progresses (Riley et al. 2013). For children, there are recommendations in relation to the desirability of making dental visits at an early age (Jones & Tomar 2005). While children who have not made a dental visit or report an irregular dental visit pattern could reflect a lack of perceived need, these measures could also reflect barriers to dental care that inhibit dental visiting or reflect problem-based attendance patterns.
This Survey gathered information from a representative sample of the Australian child population aged 5–14 years to describe the oral health status of the population and factors related to use of dental services and dental behaviours, as well as associated individual, family, and community factors such as the sociodemographic characteristics of the child's household.
Surveys provide a means of measuring a population's characteristics, self-reported and observed behaviour, and needs. Unlike a census, where all members of a population are studied, sample surveys gather information from only a portion of a population of interest. In a statistically valid survey, the sample is objectively chosen so that each member of the population will have a known non-zero chance of selection. Only then can the results be reliably projected from the sample to the population.
Surveys, however, are not exempt of errors (or bias), which can occur when some segments of the population do not participate in the survey. As not all Australian children were included in this Survey, there is potential that the sample does not accurately represent the population of interest.
Errors due to sampling depend on the sample selection strategy and can be measured statistically. Variability inherent to the sampling process is expressed using the 95% confidence interval. On the other hand, non-sampling error or bias is more problematic because it is more difficult to measure and control. Bias due to non-participation occurs when the participants differ from the non-participants or the targeted population in one or more characteristics. The potential for bias due to non-participation or non-response can be explored by examining key sociodemographic characteristics of the Survey sample, and comparing them with known characteristics of the target population.
As outlined in Chapter 3, this Survey employed rigorous sampling procedures to achieve a representative sample of the Australian child population aged 5–14 years. The procedures used to derive survey weights for this Survey reflect the standards of best practice for weighting complex survey data, and are procedures used by leading statistical agencies. Procedures used to derive survey weights ensure valid estimates and inferences of the target child population can be made. The methodologies employed in the Survey will minimise any potential bias, which will be assessed in this chapter.
Background: Advances in surgical leads have been thought to potentially enable improved low-back pain relief using SCS. A recently introduced 32-contact surgical lead, which couples multiple independent current control and anatomically-based neural targeting stimulation algorithms, allows for patient-specific programming optimization. We present a real world study of this surgical lead. Methods: A multi-center, consecutive, observational study of a new 32-contact surgical lead was carried out, using the Precision Spectra SCS System (Boston Scientific) in 100 subjects out to 12 months post-implant. We examined procedural information, programming parameters, and clinical outcomes including pain reduction (NRS), activities of daily living, and change in pain medications. Results: Surgical lead placement distribution was between T7 and L2, with most at top of T9 (26%). A mean reduction of 5.1 points (SD 2.15, p<0.001) from 7.8 (baseline) to 2.6 in overall pain was observed. A subset of subjects reporting low-back pain only exhibited a mean decrease of 6.0 points (SD 2.12, p<0.001) from 8.3 (baseline) to 2.2. Of these, 83.1% of subjects showed ≥50% back pain reduction. Increases in activities of daily living and reduction in pain medication usage were also observed in majority of subjects. Conclusions: Subjects implanted with a 32-contact surgical lead using a neural targeting algorithm demonstrated significant low-back pain reduction.
Objectives: Individuals with major depressive disorder (MDD) demonstrate poorer learning and memory skills relative to never-depressed comparisons (NDC). Previous studies report decreased volume and disrupted function of frontal lobes and hippocampi in MDD during memory challenge. However, it has been difficult to dissociate contributions of short-term memory and executive functioning to memory difficulties from those that might be attributable to long-term memory deficits. Methods: Adult males (MDD, n=19; NDC, n=22) and females (MDD, n=23; NDC, n=19) performed the Semantic List Learning Task (SLLT) during functional magnetic resonance imaging. The SLLT Encoding condition consists of 15 lists, each containing 14 words. After each list, a Distractor condition occurs, followed by cued Silent Rehearsal instructions. Post-scan recall and recognition were collected. Groups were compared using block (Encoding-Silent Rehearsal) and event-related (Words Recalled) models. Results: MDD displayed lower recall relative to NDC. NDC displayed greater activation in several temporal, frontal, and parietal regions, for both Encoding-Silent Rehearsal and the Words Recalled analyses. Groups also differed in activation patterns in regions of the Papez circuit in planned analyses. The majority of activation differences were not related to performance, presence of medications, presence of comorbid anxiety disorder, or decreased gray matter volume in MDD. Conclusions: Adults with MDD exhibit memory difficulties during a task designed to reduce the contribution of individual variability from short-term memory and executive functioning processes, parallel with decreased activation in memory and executive functioning circuits. Ecologically valid long-term memory tasks are imperative for uncovering neural correlates of memory performance deficits in adults with MDD. (JINS, 2016, 22, 412–425)
Coconut, Cocos nucifera L., is a tree that is cultivated to provide a large number of products, although it is mainly grown for its nutritional and medicinal values. Coconut oil, derived from the coconut fruit, has been recognised historically as containing high levels of saturated fat; however, closer scrutiny suggests that coconut should be regarded more favourably. Unlike most other dietary fats that are high in long-chain fatty acids, coconut oil comprises medium-chain fatty acids (MCFA). MCFA are unique in that they are easily absorbed and metabolised by the liver, and can be converted to ketones. Ketone bodies are an important alternative energy source in the brain, and may be beneficial to people developing or already with memory impairment, as in Alzheimer's disease (AD). Coconut is classified as a highly nutritious ‘functional food’. It is rich in dietary fibre, vitamins and minerals; however, notably, evidence is mounting to support the concept that coconut may be beneficial in the treatment of obesity, dyslipidaemia, elevated LDL, insulin resistance and hypertension – these are the risk factors for CVD and type 2 diabetes, and also for AD. In addition, phenolic compounds and hormones (cytokinins) found in coconut may assist in preventing the aggregation of amyloid-β peptide, potentially inhibiting a key step in the pathogenesis of AD. The purpose of the present review was to explore the literature related to coconut, outlining the known mechanistic physiology, and to discuss the potential role of coconut supplementation as a therapeutic option in the prevention and management of AD.