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Background: Neck vessel imaging is often performed in hyperacute stroke to allow neurointerventionalists to estimate access complexity. This study aimed to assess clinician agreement on catheterization strategies based on imaging in these scenarios. Methods: An electronic portfolio of 60 patients with acute ischemic stroke was sent to 53 clinicians. Respondents were asked: (1) the difficulty of catheterization through femoral access with a regular Vertebral catheter, (2) whether to use a Simmons or reverse-curve catheter initially, and (3) whether to consider an alternative access site. Agreement was assessed using Fleiss’ Kappa statistics. Results: Twenty-two respondents (7 neurologists, 15 neuroradiologists) completed the survey. Overall there was slight interrater agreement (κ=0.17, 95% CI: 0.10–0.25). Clinicians with >50 cases annually had better agreement (κ=0.22) for all questions than those with fewer cases (κ=0.07). Agreement did not significantly differ by imaging modality: CTA (κ=0.18) and MRA (κ=0.14). In 40/59 cases (67.80%), at least 25% of clinicians disagreed on whether to use a Simmons or reverse-curve catheter initially. Conclusions: Agreement on catheterization strategies remains fair at best. Our results suggest that visual assessment of pre-procedural vessels imaging is not reliable for the estimation of endovascular access complexity.
Item response theory (IRT) model applications extend well beyond cognitive ability testing, and various patient-reported outcomes (PRO) measures are among the more prominent examples. PRO (and like) constructs differ from cognitive ability constructs in many ways, and these differences have model fitting implications. With a few notable exceptions, however, most IRT applications to PRO constructs rely on traditional IRT models, such as the graded response model. We review some notable differences between cognitive and PRO constructs and how these differences can present challenges for traditional IRT model applications. We then apply two models (the traditional graded response model and an alternative log-logistic model) to depression measure data drawn from the Patient-Reported Outcomes Measurement Information System project. We do not claim that one model is “a better fit” or more “valid” than the other; rather, we show that the log-logistic model may be more consistent with the construct of depression as a unipolar phenomenon. Clearly, the graded response and log-logistic models can lead to different conclusions about the psychometrics of an instrument and the scaling of individual differences. We underscore, too, that, in general, explorations of which model may be more appropriate cannot be decided only by fit index comparisons; these decisions may require the integration of psychometrics with theory and research findings on the construct of interest.
Diagnostic criteria for major depressive disorder allow for heterogeneous symptom profiles but genetic analysis of major depressive symptoms has the potential to identify clinical and etiological subtypes. There are several challenges to integrating symptom data from genetically informative cohorts, such as sample size differences between clinical and community cohorts and various patterns of missing data.
Methods
We conducted genome-wide association studies of major depressive symptoms in three cohorts that were enriched for participants with a diagnosis of depression (Psychiatric Genomics Consortium, Australian Genetics of Depression Study, Generation Scotland) and three community cohorts who were not recruited on the basis of diagnosis (Avon Longitudinal Study of Parents and Children, Estonian Biobank, and UK Biobank). We fit a series of confirmatory factor models with factors that accounted for how symptom data was sampled and then compared alternative models with different symptom factors.
Results
The best fitting model had a distinct factor for Appetite/Weight symptoms and an additional measurement factor that accounted for the skip-structure in community cohorts (use of Depression and Anhedonia as gating symptoms).
Conclusion
The results show the importance of assessing the directionality of symptoms (such as hypersomnia versus insomnia) and of accounting for study and measurement design when meta-analyzing genetic association data.
Arctic mining has a bad reputation because the extractive industry is often responsible for a suite of environmental problems. Yet, few studies explore the gap between untouched tundra and messy megaproject from a historical perspective. Our paper focuses on Advent City as a case study of the emergence of coal mining in Svalbard (Norway) coupled with the onset of mining-related environmental change. After short but intensive human activity (1904–1908), the ecosystem had a century to respond, and we observe a lasting impact on the flora in particular. With interdisciplinary contributions from historical archaeology, archaeozoology, archaeobotany and botany, supplemented by stable isotope analysis, we examine 1) which human activities initially asserted pressure on the Arctic environment, 2) whether the miners at Advent City were “eco-conscious,” for example whether they showed concern for the environment and 3) how the local ecosystem reacted after mine closure and site abandonment. Among the remains of typical mining infrastructure, we prioritised localities that revealed the subtleties of long-term anthropogenic impact. Significant pressure resulted from landscape modifications, the import of non-native animals and plants, hunting and fowling, and the indiscriminate disposal of waste material. Where it was possible to identify individual inhabitants, these shared an economic attitude of waste not, want not, but they did not hold the environment in high regard. Ground clearances, animal dung and waste dumps continue to have an effect after a hundred years. The anthropogenic interference with the fell field led to habitat creation, especially for vascular plants. The vegetation cover and biodiversity were high, but we recorded no exotic or threatened plant species. Impacted localities generally showed a reduction of the natural patchiness of plant communities, and highly eutrophic conditions were unsuitable for liverworts and lichens. Supplementary isotopic analysis of animal bones added data to the marine reservoir offset in Svalbard underlining the far-reaching potential of our multi-proxy approach. We conclude that although damaging human–environment interactions formerly took place at Advent City, these were limited and primarily left the visual impact of the ruins. The fell field is such a dynamic area that the subtle anthropogenic effects on the local tundra may soon be lost. The fauna and flora may not recover to what they were before the miners arrived, but they will continue to respond to new post-industrial circumstances.
To investigate the association between parity and the risk of incident dementia in women.
Methods
We pooled baseline and follow-up data for community-dwelling women aged 60 or older from six population-based, prospective cohort studies from four European and two Asian countries. We investigated the association between parity and incident dementia using Cox proportional hazards regression models adjusted for age, educational level, hypertension, diabetes mellitus and cohort, with additional analysis by dementia subtype (Alzheimer dementia (AD) and non-Alzheimer dementia (NAD)).
Results
Of 9756 women dementia-free at baseline, 7010 completed one or more follow-up assessments. The mean follow-up duration was 5.4 ± 3.1 years and dementia developed in 550 participants. The number of parities was associated with the risk of incident dementia (hazard ratio (HR) = 1.07, 95% confidence interval (CI) = 1.02–1.13). Grand multiparity (five or more parities) increased the risk of dementia by 30% compared to 1–4 parities (HR = 1.30, 95% CI = 1.02–1.67). The risk of NAD increased by 12% for every parity (HR = 1.12, 95% CI = 1.02–1.23) and by 60% for grand multiparity (HR = 1.60, 95% CI = 1.00–2.55), but the risk of AD was not significantly associated with parity.
Conclusions
Grand multiparity is a significant risk factor for dementia in women. This may have particularly important implications for women in low and middle-income countries where the fertility rate and prevalence of grand multiparity are high.
Tuberculosis (TB) is generally considered a disease that principally afflicts the low-income segments of a population. In the Nanshan District of Shenzhen, China, with the economic transformation and a new Headquarters Economy (HE) emerging, there are now more cases in office workers than in manufacturing workers. To illustrate this trend, we describe a small TB outbreak in an office building located in the centre of the rapidly growing HE district. Two active pulmonary tuberculosis cases were found in workers who shared an office, and whole genome sequencing showed that the genetic distance between the strains of the two cases was just one single nucleotide polymorphism, consistent with intra-office transmission. Investigation of 30 other workers in the same or adjacent offices with interviews, interferon-gamma release assays (IGRAs) and chest X-rays, identified one new TB case and latent tuberculosis infection (LTBI) in 40.0% (12/30) of the contacts. The offices were under-ventilated. None of the IGRA positive, asymptomatic contacts agreed to receive treatment for LTBI, presumably due to TB stigma, and over the next 2 years 69.0% (20/29) of the contacts were lost to follow-up. Treatment for LTBI and stigma of TB remain challenges here. Office workers in the HE of rapidly economic developing areas should be targeted with increased vigilance by TB control programmes.
Childhood maltreatment (CM) plays an important role in the development of major depressive disorder (MDD). The aim of this study was to examine whether CM severity and type are associated with MDD-related brain alterations, and how they interact with sex and age.
Methods
Within the ENIGMA-MDD network, severity and subtypes of CM using the Childhood Trauma Questionnaire were assessed and structural magnetic resonance imaging data from patients with MDD and healthy controls were analyzed in a mega-analysis comprising a total of 3872 participants aged between 13 and 89 years. Cortical thickness and surface area were extracted at each site using FreeSurfer.
Results
CM severity was associated with reduced cortical thickness in the banks of the superior temporal sulcus and supramarginal gyrus as well as with reduced surface area of the middle temporal lobe. Participants reporting both childhood neglect and abuse had a lower cortical thickness in the inferior parietal lobe, middle temporal lobe, and precuneus compared to participants not exposed to CM. In males only, regardless of diagnosis, CM severity was associated with higher cortical thickness of the rostral anterior cingulate cortex. Finally, a significant interaction between CM and age in predicting thickness was seen across several prefrontal, temporal, and temporo-parietal regions.
Conclusions
Severity and type of CM may impact cortical thickness and surface area. Importantly, CM may influence age-dependent brain maturation, particularly in regions related to the default mode network, perception, and theory of mind.
Implementation of a novel experimental approach using a bright source of narrowband x-ray emission has enabled the production of a photoionized argon plasma of relevance to astrophysical modelling codes such as Cloudy. We present results showing that the photoionization parameter ζ = 4πF/ne generated using the VULCAN laser was ≈ 50 erg cm s−1, higher than those obtained previously with more powerful facilities. Comparison of our argon emission-line spectra in the 4.15 - 4.25 Å range at varying initial gas pressures with predictions from the Cloudy code and a simple time-dependent code are also presented. Finally we briefly discuss how this proof-of-principle experiment may be scaled to larger facilities such as ORION to produce the closest laboratory analogue to a photoionized plasma.
This study aims to investigate the climate–malaria associations in nine cities selected from malaria high-risk areas in China. Daily reports of malaria cases in Anhui, Henan, and Yunnan Provinces for 2005–2012 were obtained from the Chinese Center for Disease Control and Prevention. Generalized estimating equation models were used to quantify the city-specific climate–malaria associations. Multivariate random-effects meta-regression analyses were used to pool the city-specific effects. An inverted-U-shaped curve relationship was observed between temperatures, average relative humidity, and malaria. A 1 °C increase of maximum temperature (Tmax) resulted in 6·7% (95% CI 4·6–8·8%) to 15·8% (95% CI 14·1–17·4%) increase of malaria, with corresponding lags ranging from 7 to 45 days. For minimum temperature (Tmin), the effect estimates peaked at lag 0 to 40 days, ranging from 5·3% (95% CI 4·4–6·2%) to 17·9% (95% CI 15·6–20·1%). Malaria is more sensitive to Tmin in cool climates and Tmax in warm climates. The duration of lag effect in a cool climate zone is longer than that in a warm climate zone. Lagged effects did not vanish after an epidemic season but waned gradually in the following 2–3 warm seasons. A warming climate may potentially increase the risk of malaria resurgence in China.
To determine the impact of total household decolonization with intranasal mupirocin and chlorhexidine gluconate body wash on recurrent methicillin-resistant Staphylococcus aureus (MRSA) infection among subjects with MRSA skin and soft-tissue infection.
DESIGN
Three-arm nonmasked randomized controlled trial.
SETTING
Five academic medical centers in Southeastern Pennsylvania.
PARTICIPANTS
Adults and children presenting to ambulatory care settings with community-onset MRSA skin and soft-tissue infection (ie, index cases) and their household members.
INTERVENTION
Enrolled households were randomized to 1 of 3 intervention groups: (1) education on routine hygiene measures, (2) education plus decolonization without reminders (intranasal mupirocin ointment twice daily for 7 days and chlorhexidine gluconate on the first and last day), or (3) education plus decolonization with reminders, where subjects received daily telephone call or text message reminders.
MAIN OUTCOME MEASURES
Owing to small numbers of recurrent infections, this analysis focused on time to clearance of colonization in the index case.
RESULTS
Of 223 households, 73 were randomized to education-only, 76 to decolonization without reminders, 74 to decolonization with reminders. There was no significant difference in time to clearance of colonization between the education-only and decolonization groups (log-rank P=.768). In secondary analyses, compliance with decolonization was associated with decreased time to clearance (P=.018).
CONCLUSIONS
Total household decolonization did not result in decreased time to clearance of MRSA colonization among adults and children with MRSA skin and soft-tissue infection. However, subjects who were compliant with the protocol had more rapid clearance
To identify risk factors for recurrent methicillin-resistant Staphylococcus aureus (MRSA) colonization.
DESIGN
Prospective cohort study conducted from January 1, 2010, through December 31, 2012.
SETTING
Five adult and pediatric academic medical centers.
PARTICIPANTS
Subjects (ie, index cases) who presented with acute community-onset MRSA skin and soft-tissue infection.
METHODS
Index cases and all household members performed self-sampling for MRSA colonization every 2 weeks for 6 months. Clearance of colonization was defined as 2 consecutive sampling periods with negative surveillance cultures. Recurrent colonization was defined as any positive MRSA surveillance culture after clearance. Index cases with recurrent MRSA colonization were compared with those without recurrence on the basis of antibiotic exposure, household demographic characteristics, and presence of MRSA colonization in household members.
RESULTS
The study cohort comprised 195 index cases; recurrent MRSA colonization occurred in 85 (43.6%). Median time to recurrence was 53 days (interquartile range, 36–84 days). Treatment with clindamycin was associated with lower risk of recurrence (odds ratio, 0.52; 95% CI, 0.29–0.93). Higher percentage of household members younger than 18 was associated with increased risk of recurrence (odds ratio, 1.01; 95% CI, 1.00–1.02). The association between MRSA colonization in household members and recurrent colonization in index cases did not reach statistical significance in primary analyses.
CONCLUSION
A large proportion of patients initially presenting with MRSA skin and soft-tissue infection will have recurrent colonization after clearance. The reduced rate of recurrent colonization associated with clindamycin may indicate a unique role for this antibiotic in the treatment of such infection.
Infect. Control Hosp. Epidemiol. 2015;36(7):786–793
To delineate factors associated with the successful endovascular treatment of extracranial carotid dissections, the authors review their management of 13 cases.
Methods:
The records of 12 patients with 13 dissections were assessed with reference to mechanism of dissection, preoperative symptoms, presence of a pseudoaneurysm, treatment success, and etiology of treatment failure. Patients were followed prospectively and included six men and six women, ranging in age from 27 to 62 years.
Results:
Angioplasty and stenting were performed successfully in 11 of 13 procedures (10 of 12 patients). Follow-up in these 10 patients demonstrated excellent patency through the stented segment in nine of the 11 treated vessels. Two patients, both of whom suffered their original dissection as a result of endarterectomy, required further angioplasty and stenting for stenosis outside the previously treated arterial segment. Regarding the treatment failures, a stent deployment device could not navigate a tortuous loop in one, while a microwire could not be advanced beyond a pseudoaneurysm in the second. Six patients had pseudoaneurysms, four of which were treated only with stenting across the dissected arterial segment. All pseudoaneurysms treated in this fashion resolved. No permanent complications occurred as a result of endovascular therapy.
Conclusions:
Angioplasty and stenting can be performed safely to manage carotid dissection. A pseudoaneurysm or tortuous anatomy can preclude therapy although the former typically resolves if angioplasty and stenting are feasible. Dissections secondary to endarterectomy may be associated with a higher rate of restenosis after stenting and may require further treatment.