Search results for "Temporal"
showing 10 items of 1095 documents
Numerical solution of a spatio-temporal gender-structured model for hantavirus infection in rodents.
2017
In this article we describe the transmission dynamics of hantavirus in rodents using a spatio-temporal susceptible-exposed-infective-recovered (SEIR) compartmental model that distinguishes between male and female subpopulations [L.J.S. Allen, R.K. McCormack and C.B. Jonsson, Bull. Math. Biol. 68 (2006), 511--524]. Both subpopulations are assumed to differ in their movement with respect to local variations in the densities of their own and the opposite gender group. Three alternative models for the movement of the male individuals are examined. In some cases the movement is not only directed by the gradient of a density (as in the standard diffusive case), but also by a non-local convolution…
Space-time airborne disease mapping applied to detect specific behaviour of varicella in Valencia, Spain.
2015
Airborne diseases are one of humanity's most feared sicknesses and have regularly caused concern among specialists. Varicella is an airborne disease which usually affects children before the age of 10. Because of its nature, varicella gives rise to interesting spatial, temporal and spatio-temporal patterns. This paper studies spatio-temporal exploratory analysis tools to detect specific behaviour of varicella in the city of Valencia, Spain, from 2008 to 2013. These methods have shown a significant association between the spatial and the temporal component, confirmed by the space-time models applied to the data. High relative risk of varicella is observed in economically disadvantaged region…
Characterization of the repeat expansion size in C9orf72 in amyotrophic lateral sclerosis and frontotemporal dementia
2013
Hexanucleotide repeat expansions within the C9orf72 gene are the most important genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The difficulty of developing a precise method to determine the expansion size has hampered the study of possible correlations between the hexanucleotide repeat number and clinical phenotype. Here we characterize, through a new non-radioactive Southern blot protocol, the expansion size range in a series of 38 ALS and 22 FTD heterozygous carriers of >30 copies of the repeat. Maximum, median and modal hexanucleotide repeat number were higher in ALS patients than in FTD patients (P < 0.05 in all comparisons). A higher median numb…
Frontotemporal dementia: the post-tau era.
2006
As scientists have begun to decipher the molecular genetic bases of hereditary frontotemporal dementia (FTD), it has become clear that the biology of these human neurodegenerative diseases has a complexity not previously suspected. FTD has been found to be linked to several chromosomal loci including those in chromosome 9, chromosome 17, and chromosome 3. The article by Guyant-Marechal et al. in this issue of Neurology reports the clinical, pathologic, and molecular characteristics of a form of FTD associated with inclusion body myopathy and Paget disease of the bone observed in members of two families and expands our knowledge on genetically determined FTD.1 The disorder is associated with…
Neural overexcitation and implication of NMDA and AMPA receptors in a mouse model of temporal lobe epilepsy implying zinc chelation.
2006
Summary: Purpose: Zinc chelation with diethyldithiocarbamate (DEDTC) during nondamaging kainic acid administration enhances excitotoxicity to the level of cell damage. The objective of this work was to study the developing of the lesion in this model of temporal lobe epilepsy and the implications of the different types of glutamate receptors. Methods: The antagonist of the N-methyl-d-aspartate (NMDA) receptor MK-801, and the antagonist of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptor GYKI52466, were used concomitantly with intraperitoneal administration of kainic acid (15 mg/kg) followed by DEDTC (150 mg/kg) in mouse. The animals were killed at different times from 4 …
Quantitative assessment and localization of the hollowing of the temple after craniectomy and cranioplasty–The frontozygomatic shadow
2021
Background After cranioplasty, in many cases a not negligible soft tissue defect remains in the temporozygomatical area, also referred to as a hollowing defect of the temple. Objective To assess the precise localization and volume of the hollowing defect, to optimize future cranioplasties. Methods CT data of patients who received craniectomy and conventional CAD cranioplasty in our institution between 2012 and 2018 were analyzed. CT datasets prior to craniectomy and after cranioplasty were subtracted to quantify the volume and localization of the defect. Results Out of 91 patients, 21 had suitable datasets. Five cases had good cosmetic results with no defect visible, 16 patients had an app…
Temporobasal, Transsphenoidal Meningoencephalocele Becoming Symptomatic with Spontaneous Cerebrospinal Fluid Rhinorrhea: Diagnostic Work-up and Micro…
2012
Background We report the rare case of an adult transsphenoidal meningoencephalocele and outline the microneurosurgical strategy. Clinical history, the findings of computerized tomography (CT) scans and magnetic resonance imaging (MRI), the microsurgical procedure, and histopathology are reported. Case Report A 54-year-old female patient complained about cerebrospinal fluid (CSF) rhinorrhea; a transnasal biopsy of a mass in the maxillar sinus prior to diagnostic work-up was performed elsewhere. Persisting CSF leakage prompted CT and MRI, which showed brain tissue extending from the left middle cranial fossa into the left sphenoid sinus through several bony defects. The diagnosis of a trans…
Minimally invasive superficial temporal artery to middle cerebral artery bypass through a minicraniotomy: benefit of three-dimensional virtual realit…
2009
Object The aim of the authors in this study was to introduce a minimally invasive superficial temporal artery to middle cerebral artery (STA-MCA) bypass surgery by the preselection of appropriate donor and recipient branches in a 3D virtual reality setting based on 3-T MR angiography data. Methods An STA-MCA anastomosis was performed in each of 5 patients. Before surgery, 3-T MR imaging was performed with 3D magnetization-prepared rapid acquisition gradient echo sequences, and a high-resolution CT 3D dataset was obtained. Image fusion and the construction of a 3D virtual reality model of each patient were completed. Results In the 3D virtual reality setting, the skin surface, skull surface…
Dysfunction of attention switching networks in amyotrophic lateral sclerosis
2019
Objective To localise and characterise changes in cognitive networks in Amyotrophic Lateral Sclerosis (ALS) using source analysis of mismatch negativity (MMN) waveforms. Rationale The MMN waveform has an increased average delay in ALS. MMN has been attributed to change detection and involuntary attention switching. This therefore indicates pathological impairment of the neural network components which generate these functions. Source localisation can mitigate the poor spatial resolution of sensor-level EEG analysis by associating the sensor-level signals to the contributing brain sources. The functional activity in each generating source can therefore be individually measured and investigat…
Tower of London test: a comparison between conventional statistic approach and modelling based on artificial neural network in differentiating fronto…
2011
The early differentiation of Alzheimer’s disease (AD) from frontotemporal dementia (FTD) may be difficult. The Tower of London (ToL), thought to assess executive functions such as planning and visuo-spatial working memory, could help in this purpose. Twentytwo Dementia Centers consecutively recruited patients with early FTD or AD. ToL performances of these groups were analyzed using both the conventional statistical approaches and the Artificial Neural Networks (ANNs) modelling. Ninety-four non aphasic FTD and 160 AD patients were recruited. ToL Accuracy Score (AS) significantly (p < 0.05) The use of hidden information contained in the different items of ToL and the non linear processing of…