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To define optimal thromboprophylaxis strategy after stent implantation in superior or total cavopulmonary connections.
Stent thrombosis is a rare complication of intravascular stenting, with a perceived higher risk in single-ventricle patients.
All patients who underwent stent implantation within superior or total cavopulmonary connections (caval vein, innominate vein, Fontan, or branch pulmonary arteries) were included. Cohort was divided into aspirin therapy alone versus advanced anticoagulation, including warfarin, enoxaparin, heparin, or clopidogrel. Primary endpoint was in-stent or downstream thrombus, and secondary endpoints included bleeding complications.
A total of 58 patients with single-ventricle circulation underwent 72 stent implantations. Of them 14 stents (19%) were implanted post-superior cavopulmonary connection and 58 (81%) post-total cavopulmonary connection. Indications for stenting included vessel/conduit stenosis (67%), external compression (18%), and thrombotic occlusion (15%). Advanced anticoagulation was prescribed for 32 (44%) patients and aspirin for 40 (56%) patients. Median follow up was 1.1 (25th–75th percentile, 0.5–2.6) years. Echocardiograms were available in 71 patients (99%), and advanced imaging in 44 patients (61%). Thrombosis was present in two patients on advanced anticoagulation (6.3%) and none noted in patients on aspirin (p = 0.187). Both patients with in-stent thrombus underwent initial stenting due to occlusive left pulmonary artery thrombus acutely post-superior cavopulmonary connection. There were seven (22%) significant bleeding complications for advanced anticoagulation and none for aspirin (p < 0.001).
Antithrombotic strategy does not appear to affect rates of in-stent thrombus in single-ventricle circulations. Aspirin alone may be sufficient for most patients undergoing stent implantation, while pre-existing thrombus may warrant advanced anticoagulation.
Few studies have used genomic epidemiology to understand tuberculosis (TB) transmission in rural and remote settings – regions often unique in history, geography and demographics. To improve our understanding of TB transmission dynamics in Yukon Territory (YT), a circumpolar Canadian territory, we conducted a retrospective analysis in which we combined epidemiological data collected through routine contact investigations with clinical and laboratory results. Mycobacterium tuberculosis isolates from all culture-confirmed TB cases in YT (2005–2014) were genotyped using 24-locus Mycobacterial Interspersed Repetitive Units-Variable Number of Tandem Repeats (MIRU-VNTR) and compared to each other and to those from the neighbouring province of British Columbia (BC). Whole genome sequencing (WGS) of genotypically clustered isolates revealed three sustained transmission networks within YT, two of which also involved BC isolates. While each network had distinct characteristics, all had at least one individual acting as the probable source of three or more culture-positive cases. Overall, WGS revealed that TB transmission dynamics in YT are distinct from patterns of spread in other, more remote Northern Canadian regions, and that the combination of WGS and epidemiological data can provide actionable information to local public health teams.
This article summarizes the results of controlled experiments in which flaked-stone points that varied in impact strength by a factor of almost three were shot at media that were increasingly inelastic and therefore likely to break the points. Broken tips were reworked if possible, and used again under the same conditions. Our results show that all damage to low impact-strength materials, especially obsidian, was generally catastrophic, and, consequently, these points could only rarely be reworked. The fact that low-strength stones were commonly used to make small arrowpoints suggests that reworking was not a primary concern for their designers. Furthermore, in those instances when broken tips could be reworked, their performance declined. In addition, reworking broken points also resulted in shapes that are uncommon in many arrowpoint assemblages. Our results suggest that the original design attributes of arrowpoints may have been less affected by reworking, and, consequently, may more accurately suggest temporal and behavioral associations.
Objectives: Studies of neurocognitively elite older adults, termed SuperAgers, have identified clinical predictors and neurobiological indicators of resilience against age-related neurocognitive decline. Despite rising rates of older persons living with HIV (PLWH), SuperAging (SA) in PLWH remains undefined. We aimed to establish neuropsychological criteria for SA in PLWH and examined clinically relevant correlates of SA. Methods: 734 PLWH and 123 HIV-uninfected participants between 50 and 64 years of age underwent neuropsychological and neuromedical evaluations. SA was defined as demographically corrected (i.e., sex, race/ethnicity, education) global neurocognitive performance within normal range for 25-year-olds. Remaining participants were labeled cognitively normal (CN) or impaired (CI) based on actual age. Chi-square and analysis of variance tests examined HIV group differences on neurocognitive status and demographics. Within PLWH, neurocognitive status differences were tested on HIV disease characteristics, medical comorbidities, and everyday functioning. Multinomial logistic regression explored independent predictors of neurocognitive status. Results: Neurocognitive status rates and demographic characteristics differed between PLWH (SA=17%; CN=38%; CI=45%) and HIV-uninfected participants (SA=35%; CN=55%; CI=11%). In PLWH, neurocognitive groups were comparable on demographic and HIV disease characteristics. Younger age, higher verbal IQ, absence of diabetes, fewer depressive symptoms, and lifetime cannabis use disorder increased likelihood of SA. SA reported increased independence in everyday functioning, employment, and health-related quality of life than non-SA. Conclusions: Despite combined neurological risk of aging and HIV, youthful neurocognitive performance is possible for older PLWH. SA relates to improved real-world functioning and may be better explained by cognitive reserve and maintenance of cardiometabolic and mental health than HIV disease severity. Future research investigating biomarker and lifestyle (e.g., physical activity) correlates of SA may help identify modifiable neuroprotective factors against HIV-related neurobiological aging. (JINS, 2019, 25, 507–519)
Image feature points are detected as pixels which locally maximise a detector function, two commonly used examples of which are the (Euclidean) image gradient and the Harris–Stephens corner detector. A major limitation of these feature detectors is that they are only Euclidean-invariant. In this work, we demonstrate the application of a 2D equi-affine-invariant image feature point detector based on differential invariants as derived through the equivariant method of moving frames. The fundamental equi-affine differential invariants for 3D image volumes are also computed.
With modern X-ray instruments, precision is generally satisfactory for the analysis of MgO, Al2O3, SiO2, CaO, and Fe2O3 in finished and raw-mix cements and other similar materials. Accuracy, that is, agreement between cheraicaland X-ray values, quite frequently is much worse than precision. Some typical examples illustrating this point are reviewed.
In the soft region, generally, it has not been possible to assign the cause of iuaccuracy to interelement effects. The hypothesis is formulated that in the soft region this problem could be due to mineralogical differences and inhomogeneity on a micro scale. Theoretical calculations support the plausibility of this argument.
To improve accuracy, present techniques have been based on type standardization, acid digestion fusion using a high flux-to-sample ratio, etc. In general, these methods have certain basic limitations. In order to retain useful intensities and lineto- background ratios for the soft region, 8 new fusion technique has been developed. The experimental data based on this method of reducing micro-inhomogeneity and eliminating minaralogical differences indicate improvements in accuracy. In the case of finished cements the improvements in accuracy have been quite modest. With rawmix cements, startling improvements have been obtained for the analysis of SiO2 and CaO.
Shunt-related adverse events are frequent in infants after modified Blalock–Taussig despite use of acetylsalicylic acid prophylaxis. A higher incidence of acetylsalicylic acid-resistance and sub-therapeutic acetylsalicylic acid levels has been reported in infants. We evaluated whether using high-dose acetylsalicylic acid can decrease shunt-related adverse events in infants after modified Blalock–Taussig.
In this single-centre retrospective cohort study, we included infants ⩽1-year-old who underwent modified Blalock–Taussig placement and received acetylsalicylic acid in the ICU. We defined acetylsalicylic acid treatment groups as standard dose (⩽7 mg/kg/day) and high dose (⩾8 mg/kg/day) based on the initiating dose.
There were 34 infants in each group. Both groups were similar in age, gender, cardiac defect type, ICU length of stay, and time interval to second stage or definitive repair. Shunt interventions (18 versus 32%, p=0.16), shunt thrombosis (14 versus 17%, p=0.74), and mortality (9 versus 12%, p=0.65) were not significantly different between groups. On multiple logistic regression analysis, single-ventricle morphology (odds ratio 5.2, 95% confidence interval of 1.2–23, p=0.03) and post-operative red blood cells transfusion ⩾24 hours [odds ratio 15, confidence interval of (3–71), p<0.01] were associated with shunt-related adverse events. High-dose acetylsalicylic acid treatment [odds ratio 2.6, confidence interval of (0.7–10), p=0.16] was not associated with decrease in these events.
High-dose acetylsalicylic acid may not be sufficient in reducing shunt-related adverse events in infants after modified Blalock–Taussig. Post-operative red blood cells transfusion may be a modifiable risk factor for these events. A randomised trial is needed to determine appropriate acetylsalicylic acid dosing in infants with modified Blalock–Taussig.
Grey seals (Halichoerus grypus) of the North-east Atlantic are protected at designated European Marine Sites (Special Areas of Conservation, SACs) typically during their reproductive periods and in the UK at Sites of Special Scientific Interest (SSSI). As a mobile marine species, grey seals spend other parts of their annual life cycle in non-designated habitat. There is limited information on individual grey seal movements in south-west England. Citizen science photo identification (PID) revealed the movements of 477 grey seals at a regional scale (54 haul-outs up to 230 km apart) for over a decade. Reconstructed movements showed considerable individual variability. Four SACs were linked to up to 18 non-designated sites and two SSSIs in Cornwall were linked to a maximum of 41 non-designated sites. Observations support the value of existing SSSIs at both the well-connected West and North Cornwall sites. Thirteen Marine Protected Areas (MPAs) were visited by grey seals from four SACs and two SSSIs in Cornwall. As a mobile species, grey seals could be included in English MPA management plans. The application of functional linkage from SACs and SSSIs, informed by the movements evidenced in this research, could aid management efforts. This analysis reveals grey seal movements occur across a complex network of interconnected designated and non-designated sites that need to be managed holistically for this species for which the UK has a special responsibility.
Successful conservation strategies require that taxa are prioritized because resources for planning and implementation are always limited. In this study, we created a partial checklist of crop wild relatives (CWR) that occur in the Southern African Development Community (SADC) region and identified the taxa of highest priority for regional conservation planning based on their importance for food and economic security. We found that the region contains over 1900 wild relatives of species cultivated for food, beverages, ornamental, forage/fodder, forestry, medicinal, environmental and other uses. Prioritization of these species was based on two criteria: (i) the value of the related crop for human food and economic security in the region and/or globally, and (ii) the potential or known value of the wild relatives of those crops for crop improvement. The region contains 745 CWR species related to 64 human food and beverage crops that are of high socioeconomic importance and 100 of these are of immediate priority for conservation action. The results of this study show that the SADC region contains a wealth of CWR diversity that is not only of value for food and economic security within the region but also globally. Furthermore, this study represents the first step in developing a CWR conservation and sustainable use strategy for the region, where its implementation would contribute to food security and well-being.
Hospitalized patients placed in isolation due to a carrier state or infection with resistant or highly communicable organisms report higher rates of anxiety and loneliness and have fewer physician encounters, room entries, and vital sign records. We hypothesized that isolation status might adversely impact patient experience as reported through Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) surveys, particularly regarding communication.
Retrospective analysis of HCAHPS survey results over 5 years.
A 1,165-bed, tertiary-care, academic medical center.
Patients on any type of isolation for at least 50% of their stay were the exposure group. Those never in isolation served as controls.
Multivariable logistic regression, adjusting for age, race, gender, payer, severity of illness, length of stay and clinical service were used to examine associations between isolation status and “top-box” experience scores. Dose response to increasing percentage of days in isolation was also analyzed.
Patients in isolation reported worse experience, primarily with staff responsiveness (help toileting 63% vs 51%; adjusted odds ratio [aOR], 0.77; P = .0009) and overall care (rate hospital 80% vs 73%; aOR, 0.78; P < .0001), but they reported similar experience in other domains. No dose-response effect was observed.
Isolated patients do not report adverse experience for most aspects of provider communication regarded to be among the most important elements for safety and quality of care. However, patients in isolation had worse experiences with staff responsiveness for time-sensitive needs. The absence of a dose-response effect suggests that isolation status may be a marker for other factors, such as illness severity. Regardless, hospitals should emphasize timely staff response for this population.
A theory of the Bennett pinch is presented for the case of non-relativistic electrons. In this way the basic physics of the phenomenon can be clearly demonstrated. The magnetic force acting on the electrons is transmitted to the positive ions via an electrostatic field.