Purpose To determine whether gadolinium deposits in neural tissues of patients with intracranial abnormalities following intravenous gadolinium-based contrast agent (GBCA) exposure might be related ...to blood-brain barrier integrity by studying adult patients with normal brain pathologic characteristics. Materials and Methods After obtaining antemortem consent and institutional review board approval, the authors compared postmortem neuronal tissue samples from five patients who had undergone four to 18 gadolinium-enhanced magnetic resonance (MR) examinations between 2005 and 2014 (contrast group) with samples from 10 gadolinium-naive patients who had undergone at least one MR examination during their lifetime (control group). All patients in the contrast group had received gadodiamide. Neuronal tissues from the dentate nuclei, pons, globus pallidus, and thalamus were harvested and analyzed with inductively coupled plasma mass spectrometry (ICP-MS), transmission electron microscopy with energy-dispersive x-ray spectroscopy, and light microscopy to quantify, localize, and assess the effects of gadolinium deposition. Results Tissues from the four neuroanatomic regions of gadodiamide-exposed patients contained 0.1-19.4 μg of gadolinium per gram of tissue in a statistically significant dose-dependent relationship (globus pallidus: ρ = 0.90, P = .04). In contradistinction, patients in the control group had undetectable levels of gadolinium with ICP-MS. All patients had normal brain pathologic characteristics at autopsy. Three patients in the contrast group had borderline renal function (estimated glomerular filtration rate <45 mL/min/1.73 m
) and hepatobiliary dysfunction at MR examination. Gadolinium deposition in the contrast group was localized to the capillary endothelium and neuronal interstitium and, in two cases, within the nucleus of the cell. Conclusion Gadolinium deposition in neural tissues after GBCA administration occurs in the absence of intracranial abnormalities that might affect the permeability of the blood-brain barrier. These findings challenge current understanding of the biodistribution of these contrast agents and their safety.
RSNA, 2017.
In this paper, a random access scheme is introduced, which relies on the combination of packet erasure correcting codes and successive interference cancellation (SIC). The scheme is named coded ...slotted ALOHA. A bipartite graph representation of the SIC process, resembling iterative decoding of generalized low-density parity-check codes over the erasure channel, is exploited to optimize the selection probabilities of the component erasure correcting codes through a density evolution analysis. The capacity (in packets per slot) of the scheme is then analyzed in the context of the collision channel without feedback. Moreover, a capacity bound is developed, and component code distributions tightly approaching the bound are derived.
The spatiotemporal distribution of resources is a critical component of realized animal distributions. In agricultural landscapes, space use by generalist consumers is influenced by ephemeral ...resource availability that may produce behavioral differences across agricultural seasons, resulting in economic and production consequences and increased human-wildlife conflict. Our objective was to assess changes in habitat selection across seasons in an invasive generalist omnivore (feral pigs, Sus scrofa). Hypothesizing that pig space use is primarily driven by forage availability, we predicted strong selection for the most nutritionally beneficial crops and resource types as agricultural seasons progressed. We deployed GPS collars on 13 adult feral pigs in the Mississippi Alluvial Valley to study resource selection in a fragmented agricultural landscape. We estimated resource selection using mixed-effect logistic regression to assess variation in selection across planting, growing, harvest, and fallow seasons.
We found that feral pigs varied resource selection across seasons, particularly for corn (Zea mais). We also detected seasonal dependencies in proportional coverage on the net probability of selection of a land unit (e.g., selection was generally strongest for locations composed of both agricultural and natural habitat), resulting in marked variation in predicted space use among agricultural seasons.
These findings indicate behavioral changes in selection across agricultural seasons are driven by complex interactions between the availabilities of temporally dynamic resources and temporally static natural cover. Temporal variations in resource selection trends indicate seasonal responses to crop phenology which suggests a season-specific habitat functional response.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The effect of nano-size particles of amorphous silica (nanosilica) on the rheological behaviour and mechanical strength development of cementitious mixes is addressed. Mini-slump and rheometric tests ...were carried out on cement pastes made with three dose levels of nanosilica at different water/binder ratios. Cement paste workability resulted to be significantly lower than expected for the adopted water/binder ratios, as a consequence of instantaneous interactions between nanosilica sol and the liquid phase of cement pastes, which evidenced the formation of gels characterised by a significant water retention capacity. The resulting reduction of the mix workability was avoided by suitable addition procedures of superplasticizers. No appreciable improvement in the compressive strength development of cementitious mixes by nanosilica addition was observed, in contrast with some results from literature. This confirms conflicting experience on the problem, but some parameters affecting the strength development were identified and discussed.
Aims
Patients with non-valvular atrial fibrillation (AF) and renal insufficiency are at increased risk for ischaemic stroke and bleeding during anticoagulation. Rivaroxaban, an oral, direct factor Xa ...inhibitor metabolized predominantly by the liver, preserves the benefit of warfarin for stroke prevention while causing fewer intracranial and fatal haemorrhages.
Methods and results
We randomized 14 264 patients with AF in a double-blind trial to rivaroxaban 20 mg/day 15 mg/day if creatinine clearance (CrCl) 30-49 mL/min or dose-adjusted warfarin (target international normalized ratio 2.0-3.0). Compared with patients with CrCl >50 mL/min (mean age 73 years), the 2950 (20.7%) patients with CrCl 30-49 mL/min were older (79 years) and had higher event rates irrespective of study treatment. Among those with CrCl 30-49 mL/min, the primary endpoint of stroke or systemic embolism occurred in 2.32 per 100 patient-years with rivaroxaban 15 mg/day vs. 2.77 per 100 patient-years with warfarin hazard ratio (HR) 0.84; 95% confidence interval (CI) 0.57-1.23 in the per-protocol population. Intention-to-treat analysis yielded similar results (HR 0.86; 95% CI 0.63-1.17) to the per-protocol results. Rates of the principal safety endpoint (major and clinically relevant non-major bleeding: 17.82 vs. 18.28 per 100 patient-years; P = 0.76) and intracranial bleeding (0.71 vs. 0.88 per 100 patient-years; P = 0.54) were similar with rivaroxaban or warfarin. Fatal bleeding (0.28 vs. 0.74% per 100 patient-years; P = 0.047) occurred less often with rivaroxaban.
Conclusion
Patients with AF and moderate renal insufficiency have higher rates of stroke and bleeding than those with normal renal function. There was no evidence of heterogeneity in treatment effect across dosing groups. Dose adjustment in ROCKET-AF yielded results consistent with the overall trial in comparison with dose-adjusted warfarin.
A novel pulse-width modulation (PWM) architecture for all-digital transmitters (ADT) that achieves good in-band and out-band performance with a very low ratio between the modulated signal frequency ...and the carrier frequency is presented in this paper. The proposed scheme reduces the harmonics leaving only those corresponding to multiples of the carrier frequency, overcoming the spectral limitations of other PWM implementations and relaxing the filter requirements. The binary signal is obtained using a table-based approach with very low computational complexity, mapping the complex I/Q baseband signal to duty cycles of a square wave with low distortion. In addition, a new parallelized noise shaping circuit to reduce the distortion caused by the discretization of the duty-time intervals is presented. The digital radio frequency signal is generated using a high-speed serializer and a standard pulse former. The ADT is simulated under different scenarios to evaluate the influence of time resolution in terms of Adjacent Channel Power Ratio (ACPR) and Error Vector Magnitude (EVM). The transmitter performance is verified by an FPGA implementation using 64-QAM modulated signals, achieving values of ACPR1, ACPR2, and EVM better than −47 dBc, −53 dBc, and −35 dB, respectively, using 64 quantization levels for the PWM signal.
Introduction
The effects of antidepressant and antipsychotic medications in the perinatal period in both mothers and children have been a subject of interest for many decades. Risks and benefits ...should be considered according to the illness stage, trimester of pregnancy/ postpartum period, and neonatal outcomes.
Objectives
Our goal was to summarize the knowledge about the use of antidepressants and antipsychotics in the perinatal period. To illustrate the complexity of treatment decisions with clinical reports.
Methods
Review: A narrative review was carried out using the PubMed database including papers published in 2022. Evidence about the risks and benefits of using antidepressants and antipsychotics in the perinatal period is presented. Search terms: antidepressants OR antipsychotics AND (perinatal OR pregnancy OR postpartum).
Case reports (5 clinical scenarios): (1) pre-pregnancy counselling, (2-4) first-, second- and third-trimester of pregnancy, and (5)postpartum/breastfeeding.
Results
Review: (1)Depression/antidepressants. Treating maternal depressive symptoms is associated with a lower risk of pregnancy complications. Although placental passage of sertraline is low, drug monitoring is recommended. Antidepressant use in pregnancy is associated with preterm delivery and low weight at birth. (2)Psychosis/Antipsychotics. Antipsychotic intrauterine exposure is not significantly associated with increased risk of major congenital malformations. Minimum effective doses are recommended.
Case reports. (1)Pre-pregnancy counselling. Schizoaffective disorder receiving perphenazine, quetiapine and lithium. (2)First-trimester pregnancy. Discontinuation of treatment in major depressive disorder. (3-4)Second/third trimester. Occurrence of anxiety symptoms in posttraumatic stress disorder. (5)Postpartum/Breastfeeding. Discontinuation of antidepressants.
Conclusions
Shared decision-making models for antidepressants and antipsychotics prescription represent patient-centered approaches to be recommended in perinatal period.
Disclosure of Interest
None Declared
Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and ...management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.
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