Publications by authors named "HOUSTON J"

Peer victimization is a frequent occurrence for many adolescents; however, some of the psychometric properties of self-report scales assessing these experiences remain unclear. Furthermore, with an increase in access to technology, electronic aggression should also be considered. The authors examined the psychometric properties of the Multidimensional Peer Victimization Scale (MPVS; Mynard & Joseph, 2000), and developed versions to include the assessment of electronic aggression according to whether the adolescent was the target or perpetrator of peer victimization.

View Article and Find Full Text PDF

Flow cytometry is a powerful means for in vitro cellular analyses where multi-fluorescence and multi-angle light scattering can indicate unique biochemical or morphological features of single cells. Yet, to date, flow cytometry systems have lacked the ability to capture complex fluorescence dynamics due to the transient nature of flowing cells. In this contribution we introduce a simple approach for measuring multiple fluorescence lifetimes from a single cytometric event.

View Article and Find Full Text PDF

Gingipain proteases are important virulence factors from the periodontal pathogen Porphyromonas gingivalis and are the target of many in vitro studies. Due to their close biochemical properties, purification of individual gingipains is difficult and requires multiple chromatographic steps. In this study, we demonstrate that insertion of a hexahistidine affinity tag upstream of a C-terminal outer membrane translocation signal in RgpB gingipain leads to the secretion of a soluble, mature form of RgpB bearing the affinity tag that can easily be purified by nickel-chelating affinity chromatography.

View Article and Find Full Text PDF

Purpose: A methodological framework is introduced to assess and compare a conventional fluoroscopy protocol for peripheral angioplasty with a new magnetic resonant imaging (MRI)-guided protocol. Different scenarios were considered during interventions on a perfused arterial phantom with regard to time-based and cognitive task analysis, user experience and ergonomics.

Methods: Three clinicians with different expertise performed a total of 43 simulated common iliac angioplasties (9 fluoroscopic, 34 MRI-guided) in two blocks of sessions.

View Article and Find Full Text PDF

Arteriovenous prosthetic grafts are used in hemodialysis. Stenosis in the venous anastomosis is the main cause of occlusion and the role of local hemodynamics in this is considered significant. A new spiral graft design has been proposed to stabilize the flow phenomena in the host vein.

View Article and Find Full Text PDF

The present study examined the relative and cumulative predictive power of parent-child, interparental, and community aggression on youths' perceptions of the acceptability of aggression between peers and siblings. The potential for mother-child attachment to buffer the effects of violence on aggressive attitudes was tested, as well as the link between aggressive attitudes and aggressive behaviors. A diverse sample of 148 children (ages 9-14) completed measures of interparental, parent-child, and community aggression; a measure of mother-child attachment quality; and a measure of aggressive behaviors.

View Article and Find Full Text PDF

Little is known about the effect on load bearing ability of cam-type femurs following osteochondroplasty. The aim of this study was to compare the change in deformation undergone by cam-type femoral acetabular impingement femur models after resection of different volumes. Dry-bone replicas (N = 10) of two cam-type femurs (cam A and B) underwent resections of increasing volume (Surgery I, II and III) representing conservative, adequate and radical resections.

View Article and Find Full Text PDF

Introduction: Early pregnancy registration is recommended and provides an opportunity for screening, risk assessment and health promotion.

Aim: To determine the gestation at pregnancy registration for a cohort of pregnant New Zealand women who received maternity care from a midwife Lead Maternity Carer (LMC) and to determine if women are registering earlier in pregnancy.

Methods: The gestation of pregnancy at registration was reviewed for the 81,821 women who registered with a midwife LMC between 2008 and 2010 and had data recorded in the New Zealand College of Midwives Clinical Outcomes Research Database (COMCORD).

View Article and Find Full Text PDF

Thymocyte selection-associated high mobility group box protein family member 2 (TOX2) is a transcription factor belonging to the TOX family that shares a highly conserved high mobility group DNA-binding domain with the other TOX members. Although TOX1 has been shown to be an essential regulator of T-cell and natural killer (NK) cell differentiation in mice, little is known about the roles of the other TOX family members in lymphocyte development, particularly in humans. In this study, we found that TOX2 was preferentially expressed in mature human NK cells (mNK) and was upregulated during in vitro differentiation of NK cells from human umbilical cord blood (UCB)-derived CD34(+) cells.

View Article and Find Full Text PDF

Study of signal transduction in live cells benefits from the ability to visualize and quantify light emitted by fluorescent proteins (XFPs) fused to different signaling proteins. However, because cell signaling proteins are often present in small numbers, and because the XFPs themselves are poor fluorophores, the amount of emitted light, and the observable signal in these studies, is often small. An XFP's fluorescence lifetime contains additional information about the immediate environment of the fluorophore that can augment the information from its weak light signal.

View Article and Find Full Text PDF

Fluorescence lifetime measurements provide information about the fluorescence relaxation, or intensity decay, of organic fluorophores, fluorescent proteins, and other inorganic molecules that fluoresce. The fluorescence lifetime is emerging in flow cytometry and is helpful in a variety of multiparametric, single cell measurements because it is not impacted by nonlinearity that can occur with fluorescence intensity measurements. Yet time-resolved cytometry systems rely on major hardware modifications making the methodology difficult to reproduce.

View Article and Find Full Text PDF

A comprehensive review of online, official, and scientific literature was carried out in 2012-13 to develop a framework of disaster social media. This framework can be used to facilitate the creation of disaster social media tools, the formulation of disaster social media implementation processes, and the scientific study of disaster social media effects. Disaster social media users in the framework include communities, government, individuals, organisations, and media outlets.

View Article and Find Full Text PDF

Background: To assess the utility of previously developed scoring systems, we compared SEDAN, named after the components of the score (baseline blood Sugar, Early infarct signs and (hyper) Dense cerebral artery sign on admission computed tomography scan, Age, and National Institutes of Health Stroke Scale on admission), Totaled Health Risks in Vascular Events (THRIVE), Houston Intra-arterial Therapy (HIAT), and HIAT-2 scoring systems among patients receiving systemic (intravenous [IV] tissue plasminogen activator [tPA]) and endovascular (intra-arterial [IA]) treatments.

Methods: We retrospectively reviewed all IV tPA and IA patients presenting to our center from 2008-2011. The scores were assessed in patients who were treated with IV tPA only, IA only, and a combination of IV tPA and IA (IV-IA).

View Article and Find Full Text PDF

Purpose: Interventional MRI has significant potential for image guidance of iliac angioplasty and related vascular procedures. A technology framework with in-room image display, control, communication and MRI-guided intervention techniques was designed and tested for its potential to provide safe, fast and efficient MRI-guided angioplasty of the iliac arteries.

Methods: A 1.

View Article and Find Full Text PDF

Surveys of 1217 undergraduate students supported the reliability (inter-item and test-retest) and validity of the Prosocial and Aggressive Driving Inventory (PADI). Principal component analyses on the PADI items yielded two scales: Prosocial Driving (17 items) and Aggressive Driving (12 items). Prosocial Driving was associated with fewer reported traffic accidents and violations, with participants who were older and female, and with lower Boredom Susceptibility and Hostility scores, and higher scores on Agreeableness, Conscientiousness, Openness, and Neuroticism.

View Article and Find Full Text PDF

Hydrolysis plays an important role in metabolic activation of prodrugs. In the current study, species and in vitro system differences in hepatic and extrahepatic hydrolysis were investigated for 11 prodrugs. Ten prodrugs in the data set are predominantly hydrolyzed by carboxylesterases (CES), whereas olmesartan medoxomil is also metabolized by carboxymethylenebutenolidase (CMBL) and paraoxonase.

View Article and Find Full Text PDF

The black void behind the pupil was optically impenetrable before the invention of the ophthalmoscope by von Helmholtz over 150 years ago. Advances in retinal imaging and image processing, especially over the past decade, have opened a route to another unexplored landscape, the retinal neurovascular architecture and the retinal ganglion pathways linking to the central nervous system beyond. Exploiting these research opportunities requires multidisciplinary teams to explore the interface sitting at the border between ophthalmology, neurology and computing science.

View Article and Find Full Text PDF

Background: Common carotid intima media thickness (CIMT) and ankle brachial pressure index (ABPI) are used as surrogate marker of atherosclerosis, and have been shown to correlate with arterial stiffness, however their correlation with global atherosclerotic burden has not been previously assessed. We compare CIMT and ABPI with atheroma burden as measured by whole body magnetic resonance angiography (WB-MRA).

Methods: 50 patients with symptomatic peripheral arterial disease were recruited.

View Article and Find Full Text PDF

Chimeric antigen receptor (CAR)-redirected cellular therapy is an attractive modality for cancer treatment. We hypothesized that allogeneic CAR-engineered CD45RA-negative T cells can control cancer and infection without the risk of graft-versus-host disease (GVHD). We used CD19(+) MLL-rearranged leukemia as prototype because it is an aggressive and generally drug-resistant malignancy.

View Article and Find Full Text PDF

Renal artery stensosis (RAS) continues to be a problem for clinicians, with no clear consensus on how to investigate and assess the clinical significance of stenotic lesions and manage the findings. RAS caused by fibromuscular dysplasia is probably commoner than previously appreciated, should be actively looked for in younger hypertensive patients and can be managed successfully with angioplasty. Atheromatous RAS is associated with increased incidence of cardiovascular events and increased cardiovascular mortality, and is likely to be seen with increasing frequency.

View Article and Find Full Text PDF

Objective: Our objective was to use episodic memory and executive function tests to determine whether or not Chiari Malformation Type I (CM) patients experience cognitive dysfunction.

Background: CM is a neurological syndrome in which the cerebellum descends into the cervical spine causing neural compression, severe headaches, neck pain, and number of other physical symptoms. While primarily a disorder of the cervico-medullary junction, both clinicians and researchers have suspected deficits in higher-level cognitive function.

View Article and Find Full Text PDF

Recently, it has been proposed that drug permeation is essentially carrier-mediated only and that passive lipoidal diffusion is negligible. This opposes the prevailing hypothesis of drug permeation through biological membranes, which integrates the contribution of multiple permeation mechanisms, including both carrier-mediated and passive lipoidal diffusion, depending on the compound's properties, membrane properties, and solution properties. The prevailing hypothesis of drug permeation continues to be successful for application and prediction in drug development.

View Article and Find Full Text PDF

Purpose: Device tracking is crucial for interventional MRI (iMRI) because conventional device materials do not contribute to the MR signal, may cause susceptibility artifacts and are generally invisible if moved out of the scan plane. A robust method for wireless tracking and dynamic guidance of interventional devices equipped with wirelessly connected resonant circuits (wRC) is presented.

Methods: The proposed method uses weak spatially-selective excitation pulses with very low flip angle (0.

View Article and Find Full Text PDF

Background: Prior stroke within 3 months excludes patients from thrombolysis; however, patients may have computed tomography (CT) evidence of prior infarct, often of unknown time of origin. We aimed to determine if the presence of a previous infarct on pretreatment CT is a predictor of hemorrhagic complications and functional outcomes after the administration of intravenous (IV) tissue plasminogen activator (tPA).

Methods: We retrospectively analyzed consecutive patients treated with IV tPA at our institution from 2009-2011.

View Article and Find Full Text PDF

Flow cytometers are powerful high-throughput devices that capture spectroscopic information from individual particles or cells. These instruments provide a means of multi-parametric analyses for various cellular biomarkers or labeled organelles and cellular proteins. However, the spectral overlap of fluorophores limits the number of fluorophores that can be used simultaneously during experimentation.

View Article and Find Full Text PDF