Automated Analysis of Craniofacial Morphology Using Magnetic Resonance Images

Quantitative analysis of craniofacial morphology is of interest to scholars working in a wide variety of disciplines, such as anthropology, developmental biology, and medicine. T1-weighted (anatomical) magnetic resonance images (MRI) provide excellent contrast between soft tissues. Given its three-dimensional nature, MRI represents an ideal imaging modality for the analysis of craniofacial structure in living individuals. Here we describe how T1-weighted MR images, acquired to examine brain anatomy, can also be used to analyze facial features. Using a sample of typically developing adolescents from the Saguenay Youth Study (N = 597; 292 male, 305 female, ages: 12 to 18 years), we quantified inter-individual variations in craniofacial structure in two ways. First, we adapted existing nonlinear registration-based morphological techniques to generate iteratively a group-wise population average of craniofacial features. The nonlinear transformations were used to map the craniofacial structure of each individual to the population average. Using voxel-wise measures of expansion and contraction, we then examined the effects of sex and age on inter-individual variations in facial features. Second, we employed a landmark-based approach to quantify variations in face surfaces. This approach involves: (a) placing 56 landmarks (forehead, nose, lips, jaw-line, cheekbones, and eyes) on a surface representation of the MRI-based group average; (b) warping the landmarks to the individual faces using the inverse nonlinear transformation estimated for each person; and (3) using a principal components analysis (PCA) of the warped landmarks to identify facial features (i.e. clusters of landmarks) that vary in our sample in a correlated fashion. As with the voxel-wise analysis of the deformation fields, we examined the effects of sex and age on the PCA-derived spatial relationships between facial features. Both methods demonstrated significant sexual dimorphism in craniofacial structure in areas such as the chin, mandible, lips, and nose

The effect of non-steroidal anti-inflammatory drugs on in vitro glial apolipoprotein E expression - implications for the mechanisms and treatment of Alzheimer's disease /

Alzheimer's disease (AD) is a neurological disorder characterized by plaque deposition and an elevated immune response. Epidemiological studies have shown that use of non-steroidal anti-inflammatory drugs (NSAIDs) by the elderly is associated with a decreased relative risk and a delayed onset of AD. Moreover, the apolipoprotein E (apoE) gene has been proven to be a risk factor for AD with apoE &egr;4 AD patients having been found to show lower levels of brain apoE. In the present study, treatment of primary rat mixed glial cell cultures with indomethacin, aspirin, and interleukin-1beta resulted in significant increases in extracellular apoE protein. Furthermore, treatment of primary rat astrocyte cell cultures with aspirin, interleukin-6, and a cyclooxygenase-2 selective aspirin derivative was found to result in increased levels of apoE. Consequently, NSAID-induced increases in apoE protein may enhance apoE-mediated immunosuppression and compensatory synaptic plasticity, potentially resulting in decreased risk and delay of disease onset

Body image during adolescence : behavioural and neuroimaging studies

The primary objective of this thesis was to investigate body image at both the behavioural and neural levels. We describe three studies aimed at: (1) developing a novel digital methodology with which to assess perceptual aspects of body image during adolescence; (2) investigating perceptual accuracy and sensitivity to changes in the size/shape of body images among healthy adolescents; and (3) identifying the neural mechanisms of body perception using functional magnetic resonance imaging (fMRI). A novel library of digital images of adolescent bodies was created and used to characterize natural covariations in body size and shape using principal components analysis. Identified principal components were used to morph body images in a realistic manner to generate larger or smaller bodies. These morphed body-image stimuli were then used in a behavioural investigation of self body-image perception among adolescents. Male and female adolescents overestimated the size of their bodies. When compared with males, females overestimated their body size to a greater extent and showed greater sensitivity in detecting changes in body size. Overestimation of body size and detection sensitivity increased with subject age. Detection sensitivity decreased as a function of subjects' body mass index (BMI). In order to identify the underlying neural mechanisms of these effects, functional block-design and fMR-adaptation experiments were completed in healthy young adults. During both experiments, females, and not males, showed greater fMR signal in the right versus left hemisphere in the extrastriate body area (EBA) and fusiform body area (FBA). During the block-design experiment, females also demonstrated greater right EBA response compared with males. Observer BMI modulated the EBA hemispheric effect in both experiments. A significant recovery from adaptation was found in EBA and FBA with body-image morphing, indicating that both regions were sensitive to body-size changes. Ultimately, we demonstrated the successful use of a novel body-morphing method for the assessment of body image, established that sex, age, and BMI modulate accuracy of self body-size estimation and detection of changes in body size, and described evidence of EBA and FBA as the likely neural substrates of these behavioural effects

Impact of Antimicrobial Stewardship on Physician Practice in a Geriatric Facility

ABSTRACTBackground: There is a paucity of literature describing the implementation of antimicrobial stewardship programs (ASPs) in long-term care (LTC) facilities. The current study evaluated the impact of an ASP that was implemented across a geriatric facility, which included an inpatient specialty hospital and an LTC facility. The program included prospective audits with feedback, multidisciplinary education, information technology interventions, and guideline development.Objective: To investigate the impact of the ASP on physicians’ prescribing practices in this geriatric facility.Methods: Utilization data for antibiotics commonly used to treat urinary tract infections were retrieved for the period September 1, 2011, to August 31, 2013. The study examined whether there were significant changes in overall antibiotic use, ciprofloxacin use, and physician prescribing behaviour after program implementation in September 2012.Results: There was no significant change in the total number of antibiotic prescriptions for urinary tract infections in the hospital or the LTC facility after ASP implementation. Significant reductions were seen in the average days of therapy initially prescribed and the actual days of therapy after ASP implementation in the LTC facility but not the hospital. Across both facilities, significant reductions were seen in the number of ciprofloxacin prescriptions.Conclusions: The current study showed that an ASP can affect physicians’ antibiotic prescribing behaviour and antibiotic usage in an LTC environment.RÉSUMÉContexte : Il n’existe que très peu de documentation qui porte sur la mise en oeuvre de programmes de gérance des antimicrobiens dans les établissements de soins de longue durée. La présente étude a évalué l’effet d’un programme de gérance des antimicrobiens mis en oeuvre dans l’ensemble d’un centre gériatrique, qui comprenait un hôpital spécialisé et un établissement de soins de longue durée. Le programme comprenait des audits prospectifs accompagnés de rétroaction, des séances de formation multidisciplinaire, des interventions s’appuyant sur les technologies de l’information et l’élaboration de lignes directrices.Objectif : Évaluer les effets du programme de gérance des antimicrobiens sur les habitudes de prescription des médecins travaillant dans ce centre gériatrique.Méthodes : L’étude s’appuie sur les données d’utilisation des antibiotiques les plus employés pour traiter les infections urinaires recueillies entre le 1er septembre 2011 et le 31 août 2013. L’étude a examiné si des changements significatifs à l’utilisation des antimicrobiens et de la ciprofloxacine ainsi qu’aux habitudes de prescription des médecins ont résulté de la mise en oeuvre du programme en septembre 2012.Résultats : Aucun changement significatif n’a été noté dans le nombre total de prescriptions d’antibiotiques destinés à traiter les infections urinaires à l’hôpital et dans l’établissement de soins de longue durée. D’importantes réductions ont été observées dans la moyenne des jours de traitement initialement prescrits et le nombre réel de jours de traitement après la mise en oeuvre du programme à l’établissement de soins de longue durée, mais pas à l’hôpital. Aux deux établissements, des réductions significatives du nombre de prescriptions de ciprofloxacine ont été observées.Conclusions : La présente étude a montré qu’un programme de gérance des antimicrobiens peut avoir un effet sur les habitudes de prescription d’antibiotiques des médecins et sur l’utilisation des antibiotiques dans un établissement de soins de longue durée

Fetal growth data showing group results at both visits and individual data.

<p>Fetal growth data showing group results at both visits and individual data.</p

Demographics and the delivery details for all mothers.

*<p>Note that the estimated means and standard deviations for gestation at delivery and birth weight were corrected for fetal sex, maternal education (education was re-coded as an ordinal variable: 0 = 0 GCSEs; 1 = <5 GCSEs; 2 = >5 GCSEs/A-levels/degree), and maternal age as derived from the ANCOVA (IBM SPSS Statistics Version 20, NY, USA).</p

Maternal smoking during pregnancy and fetal organ growth: a magnetic resonance imaging study

Objective: To study whether maternal cigarette smoking during pregnancy is associated with alterations in the growth of fetal lungs, kidneys, liver, brain, and placenta. Design: A case-control study, with operators performing the image analysis blinded. Setting: Study performed on a research-dedicated magnetic resonance imaging (MRI) scanner (1.5 T) with participants recruited from a large teaching hospital in the United Kingdom. Participants: A total of 26 pregnant women (13 current smokers, 13 non smokers) were recruited; 18 women (10 current smokers, 8 nonsmokers) returned for the second scan later in their pregnancy. Methods: Each fetus was scanned with MRI at 22–27 weeks and 33–38 weeks gestational age (GA). Main outcome measures: Images obtained with MRI were used to measure volumes of the fetal brain, kidneys, lungs, liver and overall fetal size, as well as placental volumes. Results: Exposed fetuses showed lower brain volumes, kidney volumes, and total fetal volumes, with this effect being greater at visit 2 than at visit 1 for brain and kidney volumes, and greater at visit 1 than at visit 2 for total fetal volume. Exposed fetuses also demonstrated lower lung volume and placental volume, and this effect was similar at both visits. No difference was found between the exposed and nonexposed fetuses with regards to liver volume. Conclusion: Magnetic resonance imaging has been used to show that maternal smoking is associated with reduced growth of fetal brain, lung and kidney; this effect persists even when the volumes are corrected for maternal education, gestational age, and fetal sex. As expected, the fetuses exposed to maternal smoking are smaller in size. Similarly, placental volumes are smaller in smoking versus nonsmoking pregnant women

Lung growth data showing group results at both visits and individual data.

<p>Lung growth data showing group results at both visits and individual data.</p