425 research outputs found
Anesthesia and Sedation Practices Among Neurointerventionalists during Acute Ischemic Stroke Endovascular Therapy
Background and Purpose: Intra-arterial reperfusion therapies are expanding frontiers in acute ischemic stroke (AIS) management but there is considerable variability in clinical practice. The use of general anesthesia (GA) is one example. We aimed to better understand sedation practices in AIS. Methods: An online survey was distributed to the 68 active members of the Society of Vascular and Interventional Neurology (SVIN). Survey development was based on discussions at the SVIN Endovascular Stroke Round Table Meeting (Chicago, IL, 2008). The final survey contained 12 questions. Questions were developed as single and multiple-item responses; with an option for a free-text response. Results: There was a 72% survey response rate (N = 49/68). Respondents were interventional neurologists in practice 1–5 years (71.4%, N = 35). The mean (±SD) AIS interventions performed per year at the respondents’ institutions was 42.5 ± 25, median 35.0 (IQR 20, 60). The most frequent anesthesia type used was GA (anesthesia team), then conscious sedation (nurse administered), monitored anesthesia care (anesthesia team), and finally local analgesia alone. There was a preference for GA because of eliminating movement (65.3% of respondents; N = 32/49), perceived procedural safety (59.2%, N = 29/49), and improved procedural efficacy (42.9%, N = 21/49). However, cited limitations to GA included risk of time delay (69.4%, N = 34), of propagating cerebral ischemia due to hypoperfusion or other complications (28.6%, N = 14), and lack of adequate anesthesia workforce (20.4%, N = 7). Conclusions: The most frequent type of anesthesia used by Neurointerventionalists for AIS interventions is GA. Prior to making GA standard of care during AIS intervention, more data are needed about effects on clinical outcomes
Retaining Expression on De-identified Faces
© Springer International Publishing AG 2017The extensive use of video surveillance along with advances in face recognition has ignited concerns about the privacy of the people identifiable in the recorded documents. A face de-identification algorithm, named k-Same, has been proposed by prior research and guarantees to thwart face recognition software. However, like many previous attempts in face de-identification, kSame fails to preserve the utility such as gender and expression of the original data. To overcome this, a new algorithm is proposed here to preserve data utility as well as protect privacy. In terms of utility preservation, this new algorithm is capable of preserving not only the category of the facial expression (e.g., happy or sad) but also the intensity of the expression. This new algorithm for face de-identification possesses a great potential especially with real-world images and videos as each facial expression in real life is a continuous motion consisting of images of the same expression with various degrees of intensity.Peer reviewe
Condensed Matter Theory of Dipolar Quantum Gases
Recent experimental breakthroughs in trapping, cooling and controlling
ultracold gases of polar molecules, magnetic and Rydberg atoms have paved the
way toward the investigation of highly tunable quantum systems, where
anisotropic, long-range dipolar interactions play a prominent role at the
many-body level. In this article we review recent theoretical studies
concerning the physics of such systems. Starting from a general discussion on
interaction design techniques and microscopic Hamiltonians, we provide a
summary of recent work focused on many-body properties of dipolar systems,
including: weakly interacting Bose gases, weakly interacting Fermi gases,
multilayer systems, strongly interacting dipolar gases and dipolar gases in 1D
and quasi-1D geometries. Within each of these topics, purely dipolar effects
and connections with experimental realizations are emphasized.Comment: Review article; submitted 09/06/2011. 158 pages, 52 figures. This
document is the unedited author's version of a Submitted Work that was
subsequently accepted for publication in Chemical Reviews, copyright American
Chemical Society after peer review. To access the final edited and published
work, a link will be provided soo
Combining Path Integration and Remembered Landmarks When Navigating without Vision
This study investigated the interaction between remembered landmark and path integration strategies for estimating current location when walking in an environment without vision. We asked whether observers navigating without vision only rely on path integration information to judge their location, or whether remembered landmarks also influence judgments. Participants estimated their location in a hallway after viewing a target (remembered landmark cue) and then walking blindfolded to the same or a conflicting location (path integration cue). We found that participants averaged remembered landmark and path integration information when they judged that both sources provided congruent information about location, which resulted in more precise estimates compared to estimates made with only path integration. In conclusion, humans integrate remembered landmarks and path integration in a gated fashion, dependent on the congruency of the information. Humans can flexibly combine information about remembered landmarks with path integration cues while navigating without visual information.National Institutes of Health (U.S.) (Grant T32 HD007151)National Institutes of Health (U.S.) (Grant T32 EY07133)National Institutes of Health (U.S.) (Grant F32EY019622)National Institutes of Health (U.S.) (Grant EY02857)National Institutes of Health (U.S.) (Grant EY017835-01)National Institutes of Health (U.S.) (Grant EY015616-03)United States. Department of Education (H133A011903
Mast Cells and Gastrointestinal Dysmotility in the Cystic Fibrosis Mouse
BACKGROUND: Cystic fibrosis (CF) has many effects on the gastrointestinal tract and a common problem in this disease is poor nutrition. In the CF mouse there is an innate immune response with a large influx of mast cells into the muscularis externa of the small intestine and gastrointestinal dysmotility. The aim of this study was to evaluate the potential role of mast cells in gastrointestinal dysmotility using the CF mouse (Cftr(tm1UNC), Cftr knockout). METHODOLOGY: Wild type (WT) and CF mice were treated for 3 weeks with mast cell stabilizing drugs (ketotifen, cromolyn, doxantrazole) or were treated acutely with a mast cell activator (compound 48/80). Gastrointestinal transit was measured using gavage of a fluorescent tracer. RESULTS: In CF mice gastric emptying at 20 min post-gavage did not differ from WT, but was significantly less than in WT at 90 min post-gavage. Gastric emptying was significantly increased in WT mice by doxantrazole, but none of the mast cell stabilizers had any significant effect on gastric emptying in CF mice. Mast cell activation significantly enhanced gastric emptying in WT mice but not in CF mice. Small intestinal transit was significantly less in CF mice as compared to WT. Of the mast cell stabilizers, only doxantrazole significantly affected small intestinal transit in WT mice and none had any effect in CF mice. Mast cell activation resulted in a small but significant increase in small intestinal transit in CF mice but not WT mice. CONCLUSIONS: The results indicate that mast cells are not involved in gastrointestinal dysmotility but their activation can stimulate small intestinal transit in cystic fibrosis
In Vivo Methods for the Assessment of Topical Drug Bioavailability
This paper reviews some current methods for the in vivo assessment of local cutaneous bioavailability in humans after topical drug application. After an introduction discussing the importance of local drug bioavailability assessment and the limitations of model-based predictions, the focus turns to the relevance of experimental studies. The available techniques are then reviewed in detail, with particular emphasis on the tape stripping and microdialysis methodologies. Other less developed techniques, including the skin biopsy, suction blister, follicle removal and confocal Raman spectroscopy techniques are also described
The Medical Genome Reference Bank contains whole genome and phenotype data of 2570 healthy elderly
Population health research is increasingly focused on the genetic determinants of healthy ageing, but there is no public resource of whole genome sequences and phenotype data from healthy elderly individuals. Here we describe the first release of the Medical Genome Reference Bank (MGRB), comprising whole genome sequence and phenotype of 2570 elderly Australians depleted for cancer, cardiovascular disease, and dementia. We analyse the MGRB for single-nucleotide, indel and structural variation in the nuclear and mitochondrial genomes. MGRB individuals have fewer disease-associated common and rare germline variants, relative to both cancer cases and the gnomAD and UK Biobank cohorts, consistent with risk depletion. Age-related somatic changes are correlated with grip strength in men, suggesting blood-derived whole genomes may also provide a biologic measure of age-related functional deterioration. The MGRB provides a broadly applicable reference cohort for clinical genetics and genomic association studies, and for understanding the genetics of healthy ageing
A modified Ehrenfest formalism for efficient large-scale ab initio molecular dynamics
We present in detail the recently derived ab-initio molecular dynamics (AIMD)
formalism [Phys. Rev. Lett. 101 096403 (2008)], which due to its numerical
properties, is ideal for simulating the dynamics of systems containing
thousands of atoms. A major drawback of traditional AIMD methods is the
necessity to enforce the orthogonalization of the wave-functions, which can
become the bottleneck for very large systems. Alternatively, one can handle the
electron-ion dynamics within the Ehrenfest scheme where no explicit
orthogonalization is necessary, however the time step is too small for
practical applications. Here we preserve the desirable properties of Ehrenfest
in a new scheme that allows for a considerable increase of the time step while
keeping the system close to the Born-Oppenheimer surface. We show that the
automatically enforced orthogonalization is of fundamental importance for large
systems because not only it improves the scaling of the approach with the
system size but it also allows for an additional very efficient parallelization
level. In this work we provide the formal details of the new method, describe
its implementation and present some applications to some test systems.
Comparisons with the widely used Car-Parrinello molecular dynamics method are
made, showing that the new approach is advantageous above a certain number of
atoms in the system. The method is not tied to a particular wave-function
representation, making it suitable for inclusion in any AIMD software package.Comment: 28 pages, 5 figures, published in a special issue of J. Chem. Theory
Comp. in honour of John Perde
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Distinct clinical and neuropathological features of G51D SNCA mutation cases compared with SNCA duplication and H50Q mutation
Background: We and others have described the neurodegenerative disorder caused by G51D SNCA mutation which shares characteristics of Parkinson’s disease (PD) and multiple system atrophy (MSA). The objective of this investigation was to extend the description of the clinical and neuropathological hallmarks of G51D mutant SNCA-associated disease by the study of two additional cases from a further G51D SNCA kindred and to compare the features of this group with a SNCA duplication case and a H50Q SNCA mutation case.
Results: All three G51D patients were clinically characterised by parkinsonism, dementia, visual hallucinations, autonomic dysfunction and pyramidal signs with variable age at disease onset and levodopa response. The H50Q SNCA mutation case had a clinical picture that mimicked late-onset idiopathic PD with a good and sustained levodopa response. The SNCA duplication case presented with a clinical phenotype of frontotemporal dementia with marked behavioural changes, pyramidal signs, postural hypotension and transiently levodopa responsive parkinsonism. Detailed post-mortem neuropathological analysis was performed in all cases. All three G51D cases had abundant α-synuclein pathology with characteristics of both PD and MSA. These included widespread cortical and subcortical neuronal α-synuclein inclusions together with small numbers of inclusions resembling glial cytoplasmic inclusions (GCIs) in oligodendrocytes. In contrast the H50Q and SNCA duplication cases, had α-synuclein pathology resembling idiopathic PD without GCIs. Phosphorylated α-synuclein was present in all inclusions types in G51D cases but was more restricted in SNCA duplication and H50Q mutation. Inclusions were also immunoreactive for the 5G4 antibody indicating their highly aggregated and likely fibrillar state.
Conclusions: Our characterisation of the clinical and neuropathological features of the present small series of G51D SNCA mutation cases should aid the recognition of this clinico-pathological entity. The neuropathological features of these cases consistently share characteristics of PD and MSA and are distinct from PD patients carrying the H50Q or SNCA duplication
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