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Autism spectrum disorders (ASD) are characterized by deficits in social interaction and behavioral impairments. Several studies have reported differences in white matter generalized Fractional Anisotropy (gFA) in ASD.
We studied white matter microstructural integrity in individuals with ASD.
We conducted the first DWI-based whole brain tractography study to compare gFA in 22 deep white matter tracts in first-degree relatives of individuals with ASD to controls and individuals with ASD. Futhermore, we replicated our significants results in an independant sample.
Fifty-one first-degree relatives of individuals with ASD, 29 controls and 14 individuals with ASD participated.
We performed q-ball imaging whole-brain tractography based on 1.5 T diffusion weighted MRI over 32 non-colinear directions. Then, we computed mean gFA along 22 main deep white matter tracts. A linear mixed model using group, gender, age and IQ as fixed effects and family as a random effect was used and Bonferroni correction applied. We also recruited a replication sample comprising 23 individuals with ASD and 32 controls.
We demonstrated a significantly reduced mean gFA along the left IFOF in first-degree relatives of individuals with ASD and individuals with ASD compared with controls and replicated this finding in an independant sample of patients. A decrease in mean gFA was also observed in the left CST when we compared first-degree relatives of individuals with ASD to controls (no such decrease was present in patients).
Our work suggests that structural fronto-occipital disconnectivity may be an endophenotype of ASD.
To identify patient and provider characteristics associated with high-volume antibiotic prescribing for children in Tennessee, a state with high antibiotic utilization.
Cross-sectional, retrospective analysis of pediatric (aged <20 years) outpatient antibiotic prescriptions in Tennessee using the 2016 IQVIA Xponent (formerly QuintilesIMS) database.
Patient and provider characteristics, including county of prescription fill, rural versus urban county classification, patient age group, provider type (nurse practitioner, physician assistant, physician, or dentist), physician specialty, and physician years of practice were analyzed.
Tennessee providers wrote 1,940,011 pediatric outpatient antibiotic prescriptions yielding an antibiotic prescribing rate of 1,165 per 1,000 population, 50% higher than the national pediatric antibiotic prescribing rate. Mean antibiotic prescribing rates varied greatly by county (range, 39–2,482 prescriptions per 1,000 population). Physicians wrote the greatest number of antibiotic prescriptions (1,043,030 prescriptions, 54%) of which 56% were written by general pediatricians. Pediatricians graduating from medical school prior to 2000 were significantly more likely than those graduating after 2000 to be high antibiotic prescribers. Overall, 360 providers (1.7% of the 21,798 total providers in this dataset) were responsible for nearly 25% of both overall and broad-spectrum antibiotic prescriptions; 20% of these providers practiced in a single county.
Fewer than 2% of providers account for 25% of pediatric antibiotic prescriptions. High antibiotic prescribing for children in Tennessee is associated with specific patient and provider characteristics that can be used to design stewardship interventions targeted to the highest prescribing providers in specific counties and specialties.
Prescribers who wrote at least 1 antibiotic prescription filled at a retail pharmacy in Tennessee in 2016.
Multivariable logistic regression, including prescriber gender, birth decade, specialty, and practice location, and patient gender and age group, to determine the association with high prescribing.
In 2016, 7,949,816 outpatient oral antibiotic prescriptions were filled in Tennessee: 1,195 prescriptions per 1,000 total population. Moreover, 50% of Tennessee’s outpatient oral antibiotic prescriptions were written by 9.3% of prescribers. Specific specialties and prescriber types were associated with high prescribing: urology (odds ratio [OR], 3.249; 95% confidence interval [CI], 3.208–3.289), nurse practitioners (OR, 2.675; 95% CI, 2.658–2.692), dermatologists (OR, 2.396; 95% CI, 2.365–2.428), physician assistants (OR, 2.382; 95% CI, 2.364–2.400), and pediatric physicians (OR, 2.340; 95% CI, 2.320–2.361). Prescribers born in the 1960s were most likely to be high prescribers (OR, 2.574; 95% CI, 2.532–2.618). Prescribers in rural areas were more likely than prescribers in all other practice locations to be high prescribers. High prescribers were more likely to prescribe broader-spectrum antibiotics (P < .001).
Targeting high prescribers, independent of specialty, degree, practice location, age, or gender, may be the best strategy for implementing cost-conscious, effective outpatient antimicrobial stewardship interventions. More information about high prescribers, such as patient volumes, clinical scope, and specific barriers to intervention, is needed.
Post-traumatic stress disorder (PTSD) in response to the World Trade Center (WTC) disaster of 11 September 2001 (9/11) is one of the most prevalent and persistent health conditions among both professional (e.g. police) and non-traditional (e.g. construction worker) WTC responders, even several years after 9/11. However, little is known about the dimensionality and natural course of WTC-related PTSD symptomatology in these populations.
Data were analysed from 10 835 WTC responders, including 4035 police and 6800 non-traditional responders who were evaluated as part of the WTC Health Program, a clinic network in the New York area established by the National Institute for Occupational Safety and Health. Confirmatory factor analyses (CFAs) were used to evaluate structural models of PTSD symptom dimensionality; and autoregressive cross-lagged (ARCL) panel regressions were used to examine the prospective interrelationships among PTSD symptom clusters at 3, 6 and 8 years after 9/11.
CFAs suggested that five stable symptom clusters best represent PTSD symptom dimensionality in both police and non-traditional WTC responders. This five-factor model was also invariant over time with respect to factor loadings and structural parameters, thereby demonstrating its longitudinal stability. ARCL panel regression analyses revealed that hyperarousal symptoms had a prominent role in predicting other symptom clusters of PTSD, with anxious arousal symptoms primarily driving re-experiencing symptoms, and dysphoric arousal symptoms primarily driving emotional numbing symptoms over time.
Results of this study suggest that disaster-related PTSD symptomatology in WTC responders is best represented by five symptom dimensions. Anxious arousal symptoms, which are characterized by hypervigilance and exaggerated startle, may primarily drive re-experiencing symptoms, while dysphoric arousal symptoms, which are characterized by sleep disturbance, irritability/anger and concentration difficulties, may primarily drive emotional numbing symptoms over time. These results underscore the importance of assessment, monitoring and early intervention of hyperarousal symptoms in WTC and other disaster responders.
Longitudinal symptoms of post-traumatic stress disorder (PTSD) are often characterized by heterogeneous trajectories, which may have unique pre-, peri- and post-trauma risk and protective factors. To date, however, no study has evaluated the nature and determinants of predominant trajectories of PTSD symptoms in World Trade Center (WTC) responders.
A total of 10835 WTC responders, including 4035 professional police responders and 6800 non-traditional responders (e.g. construction workers) who participated in the WTC Health Program (WTC-HP), were evaluated an average of 3, 6 and 8 years after the WTC attacks.
Among police responders, longitudinal PTSD symptoms were best characterized by four classes, with the majority (77.8%) in a resistant/resilient trajectory and the remainder exhibiting chronic (5.3%), recovering (8.4%) or delayed-onset (8.5%) symptom trajectories. Among non-traditional responders, a six-class solution was optimal, with fewer responders in a resistant/resilient trajectory (58.0%) and the remainder exhibiting recovering (12.3%), severe chronic (9.5%), subsyndromal increasing (7.3%), delayed-onset (6.7%) and moderate chronic (6.2%) trajectories. Prior psychiatric history, Hispanic ethnicity, severity of WTC exposure and WTC-related medical conditions were most strongly associated with symptomatic trajectories of PTSD symptoms in both groups of responders, whereas greater education and family and work support while working at the WTC site were protective against several of these trajectories.
Trajectories of PTSD symptoms in WTC responders are heterogeneous and associated uniquely with pre-, peri- and post-trauma risk and protective factors. Police responders were more likely than non-traditional responders to exhibit a resistant/resilient trajectory. These results underscore the importance of prevention, screening and treatment efforts that target high-risk disaster responders, particularly those with prior psychiatric history, high levels of trauma exposure and work-related medical morbidities.
Influenza causes severe illness and deaths, and global surveillance systems use different clinical case definitions to identify patients for diagnostic testing. We used data collected during January 2007–July 2010 at hospital-based influenza surveillance sites in western Kenya to calculate sensitivity, specificity, positive predictive value, and negative predictive value for eight clinical sign/symptom combinations in hospitalized patients with acute respiratory illnesses, including severe acute respiratory illness (SARI) (persons aged 2–59 months: cough or difficulty breathing with an elevated respiratory rate or a danger sign; persons aged ⩾5 years: temperature ⩾38 °C, difficulty breathing, and cough or sore throat) and influenza-like illness (ILI) (all ages: temperature ⩾38 °C and cough or sore throat). Overall, 4800 persons aged ⩾2 months were tested for influenza; 416 (9%) had laboratory-confirmed influenza infections. The symptom combination of cough with fever (subjective or measured ⩾38 °C) had high sensitivity [87·0%, 95% confidence interval (CI) 83·3–88·9], and ILI had high specificity (70·0%, 95% CI 68·6–71·3). The case definition combining cough and any fever is a simple, sensitive case definition for influenza in hospitalized persons of all age groups, whereas the ILI case definition is the most specific. The SARI case definition did not maximize sensitivity or specificity.
Major depressive disorder during pregnancy associates with potentially detrimental consequences for mother and child. The current study examined peripheral blood gene expression as a potential biomarker for prenatal depressive symptoms.
Maternal RNA from whole blood, plasma and the Beck Depression Inventory were collected longitudinally from preconception through the third trimester of pregnancy in 106 women with a lifetime history of mood or anxiety disorders. The expression of 16 genes in whole blood involved in glucorticoid receptor (GR) signaling was assessed using real-time polymerase chain reaction. In parallel, plasma concentrations of progesterone, estradiol and cortisol were measured. Finally, we assessed ex vivo GR sensitivity in peripheral blood cells from a subset of 29 women.
mRNA expression of a number of GR-complex regulating genes was up-regulated over pregnancy. Women with depressive symptoms showed significantly smaller increases in mRNA expression of four of these genes – FKBP5, BAG1, NCOA1 and PPID. Ex vivo stimulation assays showed that GR sensitivity diminished with progression of pregnancy and increasing maternal depressive symptoms. Plasma concentrations of gonadal steroids and cortisol did not differ over pregnancy between women with and without clinically relevant depressive symptoms.
The presence of prenatal depressive symptoms appears to be associated with altered regulation of GR sensitivity. Peripheral expression of GR co-chaperone genes may serve as a biomarker for risk of developing depressive symptoms during pregnancy. The presence of such biomarkers, if confirmed, could be utilized in treatment planning for women with a psychiatric history.
We have chosen the name of GYES, one of the mythological giants with one hundred arms,
offspring of Gaia and Uranus, for our instrument study of a multifibre spectrograph for
the prime focus of the Canada-France-Hawaii Telescope. Such an instrument could provide an
excellent ground-based complement for the Gaia mission and a northern complement to the
HERMES project on the AAT. The CFHT is well known for providing a stable prime focus
environment, with a large field of view, which has hosted several imaging instruments, but
has never hosted a multifibre spectrograph. Building upon the experience gained at GÉPI
with FLAMES-Giraffe and X-Shooter, we are investigating the feasibility of a high
multiplex spectrograph (about 500 fibres) over a field of view one degree in diameter. We
are investigating an instrument with resolution in the range 15 000 to 30 000, which
should provide accurate chemical abundances for stars down to 16th magnitude and radial
velocities, accurate to 1 km s-1 for fainter stars. The study is led by
GÉPI-Observatoire de Paris with a contribution from Oxford for the study of the
positioner. The financing for the study comes from INSU CSAA and Observatoire de Paris.
The conceptual study will be delivered to CFHT for review by October 1st 2010.
During the five years of the mission, the Gaia spectrograph, the Radial Velocity
Spectrometer (RVS) will repeatedly survey the celestial sphere down to magnitude
V ~ 17–18. This talk presents: (i) the system which is currently developed within
the Gaia Data Processing and Analysis Consortium (DPAC) to reduce and calibrate the
spectra and to derive the radial and rotational velocities, (ii) the RVS expected
performances and (iii) scientific returns.
Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA), which is caused primarily by the Canadian methicillin-resistant Staphylococcus aureus-10 (CMRSA-10) strain (also known as the USA300 strain) has emerged rapidly in the United States and is now emerging in Canada. We assessed the prevalence, risk factors, microbiological characteristics and outcomes of CA-MRSA in patients with purulent skin and soft tissue infections (SSTIs) presenting to emergency departments (EDs) in the Greater Toronto Area.
Patients with Staphylococcus aureus SSTIs who presented to 7 EDs between Mar. 1 and Jun. 30, 2007, were eligible for inclusion in this study. Antimicrobial susceptibilities and molecular characteristics of MRSA strains were identified. Demographic, risk factor and clinical data were collected through telephone interviews.
MRSA was isolated from 58 (19%) of 299 eligible patients. CMRSA-10 was identified at 6 of the 7 study sites and accounted for 29 (50%) of all cases of MRSA. Telephone interviews were completed for 161 of the eligible patients. Individuals with CMRSA-10 were younger (median 34 v. 63 yr, p = 0.002), less likely to report recent antibiotic use (22% v. 67%, p = 0.046) or health care–related risk factors (33% v. 72%, p = 0.097) and more likely to report community-related risk factors (56% v. 6%, p = 0.008) than patients with other MRSA strains. CMRSA-10 SSTIs were treated with incision and drainage (1 patient), antibiotic therapy (3 patients) or both (5 patients), and all resolved. CMRSA-10 isolates were susceptible to clindamycin, tetracycline and trimethoprimsulfamethoxazole.
CA-MRSA is a significant cause of SSTIs in the Greater Toronto Area, and can affect patients without known community-related risk factors. The changing epidemiology of CA-MRSA necessitates further surveillance to inform prevention strategies and empiric treatment guidelines.
Recent laboratory measurements of plasma expansion in a plasma wake experiment are compared with analytical expressions which approximate the plasma expansion model of Crow, Auer & Allen. Good quantitative agreement was found between the data and theory for the velocity and position of the ion expansion front. These results provide an important insight into the behaviour of the expansion early in its development.
The ESA space astrometry mission Gaia will measure the positions, parallaxes and proper motions of the 1 billion brightest stars on the sky. Expected accuracies are in the 7–25 μas range down to 15 mag and sub-mas accuracies at the faint limit (20 mag). The astrometric data are complemented by low-resolution spectrophotometric data in the 330–1000 nm wavelength range and, for the brighter stars, radial velocity measurements. The scientific case covers an extremely wide range of topics in galactic and stellar astrophysics, solar system and exoplanet science, as well as the establishment of a very accurate, dense and faint optical reference frame. With a planned launch around 2012 and an (extended) operational lifetime of 6 years, final results are expected around 2021. We give a brief overview of the science goals of Gaia, the overall project organisation, expected performance, and some key technical features and challenges.
Large outbreaks of giardiasis caused by person-to-person transmission, or a combination of transmission routes, have not previously been reported. A large, prolonged giardiasis outbreak affected families belonging to a country club in a suburb of Boston, Massachusetts, during June–December 2003. We conducted a retrospective cohort study to determine the source of this outbreak. Giardiasis-compatible illness was experienced by 149 (25%) respondents to a questionnaire, and was laboratory confirmed in 97 (65%) of these cases. Of the 30 primary cases, exposure to the children's pool at the country club was significantly associated with illness (risk ratio 3·3, 95% confidence interval 1·7–6·5). In addition, 105 secondary cases probably resulted from person-to-person spread; 14 cases did not report an onset date. This outbreak illustrates the potential for Giardia to spread through multiple modes of transmission, with a common-source outbreak caused by exposure to a contaminated water source resulting in subsequent prolonged propagation through person-to-person transmission in the community. This capacity for a common-source outbreak to continue propagation through secondary person-to-person spread has been reported with Shigella and Cryptosporidium and may also be a feature of other enteric pathogens having low infectious doses.