Prevalence and Risk Factors for Methicillin-Resistant Staphylococcus aureus in an HIV-Positive Cohort

Background: Persons living with HIV (PLWH) are disproportionately burdened with methicillin-resistant Staphylococcus aureus (MRSA). Our objective was to evaluate prevalence and risks for MRSA colonization in PLWH. Methods: Adults were recruited from Johns Hopkins University AIDS Service in Baltimore, Maryland. A risk questionnaire and specimen collection from anatomic sites with culture susceptibility and genotyping were completed. Generalized estimating equation modeling identified MRSA colonization risk factors. Results: Of 500 participants,mostwere black (69%), on antiretroviral therapy (ART) (87%),with undetectable viral loads (73.4%). Median CD4 count was 487 cells/mm3 (interquartile range, 316-676.5 cells/mm3). MRSA prevalence was 15.4%, predominantly from the nares (59.7%). Forty percent were nares negative but were colonized elsewhere. Lower odds for colonizationwere associatedwith recent sexual activity (adjusted odds ratio [AOR]¼0.84, P$75,000; AOR ¼ 2.68, P \u3c .001), recent hospitalization (AOR ¼ 1.54, P \u3c .001), incarceration (AOR ¼ 1.55,

Prevalence and Risk Factors for Methicillin-Resistant Staphylococcus aureus in an HIV-Positive Cohort

Background: Persons living with HIV (PLWH) are disproportionately burdened with methicillin-resistant Staphylococcus aureus (MRSA). Our objective was to evaluate prevalence and risks for MRSA colonization in PLWH. Methods: Adults were recruited from Johns Hopkins University AIDS Service in Baltimore, Maryland. A risk questionnaire and specimen collection from anatomic sites with culture susceptibility and genotyping were completed. Generalized estimating equation modeling identified MRSA colonization risk factors. Results: Of 500 participants,mostwere black (69%), on antiretroviral therapy (ART) (87%),with undetectable viral loads (73.4%). Median CD4 count was 487 cells/mm3 (interquartile range, 316-676.5 cells/mm3). MRSA prevalence was 15.4%, predominantly from the nares (59.7%). Forty percent were nares negative but were colonized elsewhere. Lower odds for colonizationwere associatedwith recent sexual activity (adjusted odds ratio [AOR]¼0.84, P$75,000; AOR ¼ 2.68, P \u3c .001), recent hospitalization (AOR ¼ 1.54, P \u3c .001), incarceration (AOR ¼ 1.55,

Can Young Drivers Learn to Anticipate Hidden Hazards: A Driving Simulator Study

Modern technology makes possible improvements in training programs designed to develop young drivers’ abilities to anticipate hazardous situations. These improvements which come from increases in the range of scenarios to which young drivers are exposed and the number of times young drivers can practice the skills they are learning. In this study, a new Flash-based, PC training program that runs on the web, Road Aware® (RA), is evaluated using a driving simulator. The program was developed by State Farm. Twenty-four young trained drivers and twenty four young untrained drivers were asked to drive various simulated hazardous scenarios while their gaze was monitored by an eye tracking system. The results show that trained drivers were more likely to anticipate hazards than their untrained peers, a difference which was present for both near transfer (scenarios that appeared in training) and far transfer scenarios. The effectiveness of RA is compared with other hazard anticipation training programs that were evaluated on a driving simulator and in the field. It appears every bit as effective in general and more effective for some scenarios. Additionally, there is evidence suggesting that, for the first time, young drivers can be trained to anticipate hazards as well as drivers who are older and more experienced

Capture and decay of electroweak WIMPonium

The spectrum of Weakly-Interacting-Massive-Particle (WIMP) dark matter generically possesses bound states when the WIMP mass becomes sufficiently large relative to the mass of the electroweak gauge bosons. The presence of these bound states enhances the annihilation rate via resonances in the Sommerfeld enhancement, but they can also be produced directly with the emission of a low-energy photon. In this work we compute the rate for SU(2) triplet dark matter (the wino) to bind into WIMPonium - which is possible via single-photon emission for wino masses above 5 TeV for relative velocity v < O(10-2) - and study the subsequent decays of these bound states. We present results with applications beyond the wino case, e.g. for dark matter inhabiting a nonabelian dark sector; these include analytic capture and transition rates for general dark sectors in the limit of vanishing force carrier mass, efficient numerical routines for calculating positive and negative-energy eigenstates of a Hamiltonian containing interactions with both massive and massless force carriers, and a study of the scaling of bound state formation in the short-range Hulth&apos;{e}n potential. In the specific case of the wino, we find that the rate for bound state formation is suppressed relative to direct annihilation, and so provides only a small correction to the overall annihilation rate. The soft photons radiated by the capture process and by bound state transitions could permit measurement of the dark matter's quantum numbers; for wino-like dark matter, such photons are rare, but might be observable by a future ground-based gamma-ray telescope combining large effective area and a low energy threshold

Internal bone architecture in the triquetrum of extant hominids and Homo neanderthalensis

Bones on the radial side of the wrist have dominated research on the evolution and functional anatomy of the hominoid carpus. However, soft and hard tissue structures at the ulnar side of the wrist, such as reduced ulna-triquetrum articulation and the Triangular Fibrocartilage Complex (TFCC), are some of the most conspicuous synapomorphies among hominoids linked to high degrees of ulna-deviation and forearm supination [1,2]. However, there is also notable variation in the bony and soft tissue anatomy of the ulnar wrist among hominoids that affects how loads are transferred from the hand to the forearm but are not clearly understood, in part because the functional morphology of the triquetrum is understudied. Here we investigate for the first time the internal trabecular bone structure of the triquetrum and test the null hypothesis that great apes will exhibit similar distributions of relative trabecular bone volume to total volume (BV/TV) and degree of anisotropy (DA). Using a whole-bone methodology (http://www.dr-pahr.at/medtool/) this study quantifies BV/TV and DA in the triquetrum in Pongo (n=12), Gorilla (n=10), Pan (n= 10) and a temporogeographically diverse sample of modern humans (n=21), in comparison to three Homo neanderthalensis individuals (El Sidron SD-1227, Tabun C1_1-154, and Amud 1). The distribution of BV/TV and DA values are visualised across the entire bone using Paraview (3.89.0). Low DA was identified as values equal to or less than 0.20. High BV/TV was identified as the top 20% of values for that individual’s range. In line with presumed force transfer at the ulna-side wrist in hominoids [2], it is predicted that low DA values will be present at the TFCC insertion site, with high BV/TV at the lunate and hamate articulations. Low DA was observed at the TFCC insertion site in 41% of Pongo, 100% of Gorilla, 90% of Pan, 100% of Homo neanderthalensis, and 76% of Homo sapiens. High BV/TV was observed at the hamate articulation site in 75% of Pongo, 90% of Gorilla, 70% of Pan, 100% of Homo neanderthalensis and 61% of Homo sapiens. High BV/TV was observed at the lunate articulation site in 91% of Pongo, 20% of Gorilla, 0% of Pan, 33% of Homo neanderthalensis, and 0.04% of Homo sapiens. Overall, these results suggest relatively consistent interspecific patterns in the trabecular structure of the triquetrum which contrasts the interspecific variation reported in some previous studies, including the capitate [3]. DA predictions were supported for all species except Pongo, where there was only partial support. Predictions for high BV/TV at the triquetrohamate joint were broadly supported while predictions for high BV/TV at the triquetrolunate had mixed support. This pattern suggests that force transfer between the lunate and triquetrum is lower than that between the hamate and triquetrum. Pongo is the exception to this pattern with 91% exhibiting high BV/TV at the triquetrolunate joint, which, when combined with the DA results, may reflect a less-developed TFCC [2] and a greater reliance on the (relatively large) lunate to support ulna-side force transfer compared with other great apes. Although the Neanderthal triquetrum morphology is primitive relative to H. sapiens [4], all three show a BV/TV and DA pattern most similar to that of modern humans. This suggests a similar force transfer pattern at the ulna-side wrist in Neanderthals despite this primitive morphology. There is considerable debate as to whether Neanderthals utilised the same grip patterns as modern H. sapiens and the ulna-side wrist may shed light on the importance of carpal morphology in predicting force transfer and grip types among hominins

Achieving Cardiovascular Health in Young Adulthood—Which Adolescent Factors Matter?

AbstractPurposeTo examine associations of adolescent body mass index (BMI), tobacco use, and physical activity with optimal physiologic cardiovascular health (CVH) in adulthood.MethodsData were from 12,139 participants in Waves I (1995–1996) and IV (2007–2008) of the National Longitudinal Study of Adolescent Health. We defined optimal CVH as normal blood pressure, glucose, and cholesterol without diabetes or cardiovascular disease. We used logistic regression to estimate odds of having optimal CVH at ages 24–32 years (Wave IV) according to BMI category, smoking status, and physical activity at ages 11–19 years (Wave I).ResultsFew young adults (16%) had optimal CVH. Adolescents with normal BMI were more than twice as likely to have optimal young adult CVH compared to those who were obese (adjusted odds ratio, 2.77; 95% confidence interval, 1.97–3.89). Adolescent smoking and physical activity did not predict young adult CVH.ConclusionsLower adolescent BMI is associated with young adult CVH

Internal bone architecture in the capitate of extant hominids

Due to its central role in wrist function and distinctive morphology, the capitate has been an important element for drawing inferences about fossil hominin locomotor and manipulative capacities [1-3]. However, difficulties in studying the numerous, intricate joints of the wrist have led to disagreement about the functional significance of various aspects of its morphology [1-3]. As internal bone is known to adapt to load experienced during life, its structure may reflect the actual postures and behaviours of an individual [4,5]. To date, it is unclear whether the internal bone of the capitate might reflect differences in hand use among hominids. Furthermore, it is not currently understood how cortical and trabecular bone of carpals interact and adapt to cope with the high load and mechanical demands of suspensory or quadrupedal locomotion. To examine the relationship between internal bone architecture and locomotor behaviour, we test for group differences in bone volume to total volume (BV/TV), degree of anisotropy (DA), and cortical thickness (Ct.Th). Further, we analyse the relative distributions of cortical and trabecular bone to assess whether distribution is similar between the locomotor groups. Using a whole-bone method (http://www.dr-pahr.at/medtool/), BV/TV, DA, and Ct.Th were measured in four extant ape genera (n=69) representing bipedal (Homo), knuckle-walking (Pan, Gorilla) and suspensory (Pongo) locomotion. The capitate was partitioned for separate analysis as the proximal portion forms part of the midcarpal joint, while the distal portion forms part of the carpometacarpal joint [3]. BV/TV was measured twice, quantifying just the trabecular region and then the combined cortical and trabecular region. Mean group differences were examined with a KruskalWallis one-way ANOVA and Pairwise Wilcoxon Rank Sum test. Intraspecific ratios were calculated to facilitate comparison of the bone parameters between the proximal and distal regions of each genus. Parameters differed between the genera across all capitate regions (p=<0.001 for all tests), except distal DA (p= 0.593). Ct.Th was the most important parameter for differentiating locomotor groups as distribution across the bone was distinctly different between the human and non-human apes. Compared to the proximal, the distal cortex was thicker in all genera; a 12% increase was seen inHomo, 52% in Pan, 62% inGorilla and 79% in Pongo. This Ct.Th increase coincides with the attachment sites for several ligaments, and might indicate that tensional strain, which has a lower failure load than compressive strain, has an impact on cortical bone functional adaptation. These intergeneric differences further suggest that the hand of bipedal Homo may not experience a similar magnitude of strain. Trabecular BV/TV was higher in the proximal capitate for all genera suggesting it plays a bigger role in adapting to midcarpal joint load than cortical bone in this region. DA in the distal capitate was not significantly different among the genera. This may indicate that the limited mobility at the distal region results in a similar DA, irrespective of hand use. Homo and Pongo were differentiated from the knuckle-walking taxa by having higher DA in the proximal capitate, which was unexpected given our assumption of more variable wrist postures than that of knuckle-walking apes. Results of this study indicate that (1) capitate bone structure is informative for reconstructing hand use and (2) partitioning of ‘cortical’ and ‘trabecular’ regions in carpals (and likely tarsals) may obscure functionally relevant information in the carpus of hominids

Detecting bone functional adaptation in the capitate of extant hominoids

As a central component of the midcarpal and carpometacarpal joints, the capitate plays a primary role in primate hand biomechanics. Capitate morphology facilitates mobility of the midcarpal joint in suspensory apes, limits extension in knuckle-walking apes, and in humans stabilises the capitometacarpal joint for tool behaviours. Biomechanical loading of the capitate varies across taxa with respect to changes in hand and wrist postures associated with different locomotor and manipulative repertoires. As a metabolically active tissue, internal trabecular bone is known to remodel over the lifetime of an individual, and has the potential to reveal patterns of in vivo loading

Trabecular bone structure of the proximal capitate in extant hominids and fossil hominins with implications for midcarpal joint loading and the dart‐thrower's motion

Objectives: This research examines whether the distribution of trabecular bone in the proximal capitates of extant hominids, as well as several fossil hominin taxa, is associated with the oblique path of the midcarpal joint known as the dart‐thrower's motion (DTM). Materials and Methods: We analyzed proximal capitates from extant (Pongo n = 12; Gorilla n = 11; Pan n = 10; fossil and recent Homo sapiens n = 29) and extinct (Australopithecus sediba n = 2; Homo naledi n = 1; Homo floresiensis n = 2; Neandertals n = 3) hominids using a new canonical holistic morphometric analysis, which quantifies and visualizes the distribution of trabecular bone using relative bone volume as a fraction of total volume (rBV/TV). Results: Homo sapiens and Neandertals had a continuous band of high rBV/TV that extended across the scaphoid, lunate, and hamate subarticular regions, but other fossil hominins and extant great apes did not. A. sediba expressed a distinct combination of human‐like and Pan‐like rBV/TV distribution. Both H. floresiensis and H. naledi had high rBV/TV on the ulnar‐side of the capitate but low rBV/TV on the radial‐side. Conclusion: The proximal capitates of H. sapiens and Neandertals share a distinctive distribution of trabecular bone that suggests that these two species of Homo regularly load(ed) their midcarpal joints along the full extent of the oblique path of the DTM. The observed pattern in A. sediba suggests that human‐like stress at the capito‐scaphoid articular surface was combined with Pan‐like wrist postures, whereas the patterns in H. floresiensis and H. naledi suggest their midcarpal joints were loaded differently from that of H. sapiens and Neandertals