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Find video protocols related to scientific articles indexed in Pubmed.
Ultrasound Assessment of Endothelial-Dependent Flow-Mediated Vasodilation of the Brachial Artery in Clinical Research.
J Vis Exp
PUBLISHED: 11-20-2014
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The vascular endothelium is a monolayer of cells that cover the interior of blood vessels and provide both structural and functional roles. The endothelium acts as a barrier, preventing leukocyte adhesion and aggregation, as well as controlling permeability to plasma components. Functionally, the endothelium affects vessel tone. Endothelial dysfunction is an imbalance between the chemical species which regulate vessel tone, thombroresistance, cellular proliferation and mitosis. It is the first step in atherosclerosis and is associated with coronary artery disease, peripheral artery disease, heart failure, hypertension, and hyperlipidemia. The first demonstration of endothelial dysfunction involved direct infusion of acetylcholine and quantitative coronary angiography. Acetylcholine binds to muscarinic receptors on the endothelial cell surface, leading to an increase of intracellular calcium and increased nitric oxide (NO) production. In subjects with an intact endothelium, vasodilation was observed while subjects with endothelial damage experienced paradoxical vasoconstriction. There exists a non-invasive, in vivo method for measuring endothelial function in peripheral arteries using high-resolution B-mode ultrasound. The endothelial function of peripheral arteries is closely related to coronary artery function. This technique measures the percent diameter change in the brachial artery during a period of reactive hyperemia following limb ischemia. This technique, known as endothelium-dependent, flow-mediated vasodilation (FMD) has value in clinical research settings. However, a number of physiological and technical issues can affect the accuracy of the results and appropriate guidelines for the technique have been published. Despite the guidelines, FMD remains heavily operator dependent and presents a steep learning curve. This article presents a standardized method for measuring FMD in the brachial artery on the upper arm and offers suggestions to reduce intra-operator variability.
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Preventing CLABSIs Among Pediatric Hematology/Oncology Inpatients: National Collaborative Results.
Pediatrics
PUBLISHED: 11-19-2014
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Central lines (CLs) are essential for the delivery of modern cancer care to children. Nonetheless, CLs are subject to potentially life-threatening complications, including central line-associated bloodstream infections (CLABSIs). The objective of this study was to assess the feasibility of a multicenter effort to standardize CL care and CLABSI tracking, and to quantify the impact of standardizing these processes on CLABSI rates among pediatric hematology/oncology inpatients.
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Unilateral Prostaglandin-Associated Periorbitopathy: A Syndrome Involving Upper Eyelid Retraction Distinguishable From the Aging Sunken Eyelid.
Ophthal Plast Reconstr Surg
PUBLISHED: 11-14-2014
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To study the effects of prostaglandin analogue drops on the eyelids and adnexa in unilaterally treated subjects with the intention of qualifying, quantifying, and categorizing the characteristics of prostaglandin-associated periorbitopathy (PAP).
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Explantation of the Novel Ahmed Glaucoma Valve M4 Implant.
J. Glaucoma
PUBLISHED: 11-14-2014
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To report a series of cases involving Ahmed Glaucoma Valve M4 (AGV) explantation and to discuss the surgical technique to remove the drainage device.
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Estimating the State-Level Supply of Cancer Care Providers: Preparing to Meet Workforce Needs in the Wake of Health Care Reform.
J Oncol Pract
PUBLISHED: 11-14-2014
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This study describes the supply of cancer care providers-physicians, nurse practitioners (NPs), and physician assistants (PAs)-in Nebraska and analyzes changes in the supply over a 5-year period.
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A rare spontaneous enterocutaneous fistula.
J Surg Case Rep
PUBLISHED: 11-14-2014
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A 70-year-old woman presented with a short history of a spontaneous enterocutaneos fistula in the left inguinal region. A laparotomy revealed a fistulizing Richter's hernia. The fistulizing small bowel segment was resected and the femoral hernia repaired from below. Although rare, a complicating Richter's hernia should be considered in the differential diagnosis of a groin fistula.
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Variable Left-hemisphere Language and Orthographic Lateralization Reduces Right-hemisphere Face Lateralization.
J Cogn Neurosci
PUBLISHED: 11-13-2014
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It is commonly believed that, in right-handed individuals, words and faces are processed by distinct neural systems: one in the left hemisphere (LH) for words and the other in the right hemisphere (RH) for faces. Emerging evidence suggests, however, that hemispheric selectivity for words and for faces may not be independent of each other. One recent account suggests that words become lateralized to the LH to interact more effectively with language regions, and subsequently, as a result of competition with words for representational space, faces become lateralized to the RH. On this interactive account, left-handed individuals, who as a group show greater variability with respect to hemispheric language dominance, might be expected to show greater variability in their degree of RH lateralization of faces as well. The current study uses behavioral measures and ERPs to compare the hemispheric specialization for both words and faces in right- and left-handed adult individuals. Although both right- and left-handed groups demonstrated an LH over RH superiority in discrimination accuracy for words, only the right-handed group demonstrated an RH over LH advantage in discrimination accuracy for faces. Consistent with this, increased right-handedness was related to an increase in RH superiority for face processing, as measured by the strength of the N170 ERP component. Interestingly, the degree of RH behavioral superiority for face processing and the amplitude of the RH N170 for faces could be predicted by the magnitude of the N170 ERP response to words in the LH. These results are discussed in terms of a theoretical account in which the typical RH face lateralization fails to emerge in individuals with atypical language lateralization because of weakened competition from the LH representation of words.
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Inflammatory stimuli induce inhibitory S-nitrosylation of the deacetylase SIRT1 to increase acetylation and activation of p53 and p65.
Sci Signal
PUBLISHED: 11-13-2014
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Inflammation increases the abundance of inducible nitric oxide synthase (iNOS), leading to enhanced production of nitric oxide (NO), which can modify proteins by S-nitrosylation. Enhanced NO production increases the activities of the transcription factors p53 and nuclear factor ?B (NF-?B) in several models of disease-associated inflammation. S-nitrosylation inhibits the activity of the protein deacetylase SIRT1. SIRT1 limits apoptosis and inflammation by deacetylating p53 and p65 (also known as RelA), a subunit of NF-?B. We showed in multiple cultured mammalian cell lines that NO donors or inflammatory stimuli induced S-nitrosylation of SIRT1 within CXXC motifs, which inhibited SIRT1 by disrupting its ability to bind zinc. Inhibition of SIRT1 reduced deacetylation and promoted activation of p53 and p65, leading to apoptosis and increased expression of proinflammatory genes. In rodent models of systemic inflammation, Parkinson's disease, or aging-related muscular atrophy, S-nitrosylation of SIRT1 correlated with increased acetylation of p53 and p65 and activation of p53 and NF-?B target genes, suggesting that S-nitrosylation of SIRT1 may represent a proinflammatory switch common to many diseases and aging.
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Nature du lexique émotionnel produit en situation d'appréciation et de rejet de dessins d'humour noir et d'humour non noir.
Can J Exp Psychol
PUBLISHED: 11-11-2014
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The aim of the present research was to show that the appreciation and the rejection of dark humorous cartoons trigger different emotional reactions compared to nondark ones. Thus, participants rated each humorous cartoon on incongruous, surprising, understanding and funniness scales. Then they chose the one they most like and the one they most dislike. Finally they explain the reasons of their choice and their emotional experience. Results highlighted that dark honour's appreciation and rejection trigger specific emotional experience. Participants used more emotional lexicon to describe the emotional experience associated with dark humorous cartoons. For dark and nondark humorous cartoons and for the one they liked and the one they disliked, participants used both positive and negative emotional lexicon because their emotional experience is complex and ambivalent. Appraisal theory of emotion (Sander & Scherer, 2009) can explain these results. This cognitive theory involves an assessment via social norms and may explain that transgressive content of dark honour trigger proportionally more emotions of negative valence. (PsycINFO Database Record (c) 2014 APA, all rights reserved).
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INCREASED COAGULATION AND SUPPRESSED GENERATION OF ACTIVATED PROTEIN C IN AGED MICE DURING INTRA-ABDOMINAL SEPSIS.
Am. J. Physiol. Heart Circ. Physiol.
PUBLISHED: 11-09-2014
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Sepsis is a life-threatening clinical condition which is particularly serious among the elderly who experience considerably higher mortality rates compared to younger patients. Using a sterile endotoxemia model, we previously reported age-dependent mortality in conjunction with enhanced coagulation and insufficient levels of anti-coagulant factor activated protein C (aPC). The purpose of the present study was to further investigate the mechanisms for age-dependent coagulation and aPC insufficiency during experimental sepsis. Intra-abdominal sepsis was induced by cecal ligation and puncture (CLP) using 21 or 16 gauge (G) needles (double-puncture) on young (4-6 months old) and aged (20-25 months old) male C57BL/6 mice. Compared to young, aged mice showed significantly increased mortality (92% vs 28%), systemic inflammation, and coagulation in the lung and kidney after 21G CLP. Young mice with more severe CLP (16G) showed a mortality rate and inflammation equivalent to aged mice with 21G CLP; however, enhanced coagulation and kidney dysfunction were significant only in the aged. In young mice, increased levels of aPC after CLP was coupled with reduced levels of PC suggesting the conversion of PC to aPC; however, PC and aPC levels remained unchanged in aged mice, indicating a lack of PC to aPC conversion. Activation of fibrinolysis, determined by plasma D-dimer levels, was similar regardless of age or CLP severity and plasminogen activator inhibitor-1 (PAI-1), an inhibitor of fibrinolysis, showed severity-dependent induction independent of age. These results suggest that enhanced coagulation in aged mice during sepsis is due to dysfunction of the PC activation mechanism.
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Age-Associated Increase in Cytokine Production During Systemic Inflammation-II: The Role of IL-1? in Age-Dependent IL-6 Upregulation in Adipose Tissue.
J. Gerontol. A Biol. Sci. Med. Sci.
PUBLISHED: 10-27-2014
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Expression of interleukin-6 (IL-6) upon acute inflammatory stress is significantly augmented by aging in adipose tissue, a major source of this cytokine. In the present study, we examined the mechanism of age-dependent IL-6 overproduction using visceral white adipose tissue from C57BL/6 mice. Upon treatment with lipopolysaccharide (LPS) in vitro, IL-6 was produced by adipose tissue explants, and secreted levels were significantly higher in cultures from aged (24 months) mice compared to young (4 months). Interleukin 1 beta (IL-1?) and tumor necrosis factor alpha (TNF?), two inducers of IL-6, were mainly produced by the lungs and spleen rather than adipose tissue in mice after LPS injection. Treatment of adipose explants with physiological levels of IL-1? induced significant age-dependent secretion of IL-6, while treatment with TNF? had little effect, demonstrating an augmented response of adipose tissues to IL-1? in the aged. In vitro experiments utilizing a neutralizing antibody against IL-1? and in vivo experiments utilizing IL-1-receptor-1 deficient mice, confirmed that IL-6 overproduction in the aged is regulated by autocrine/paracrine action of IL-1? which specifically occurs in aged adipose tissues. These findings indicate an elevated inflammatory potential of adipose tissue in the aged and a unique IL-1?-mediated mechanism for IL-6 overproduction, which may impact age-associated vulnerability to acute inflammatory diseases such as sepsis.
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Cortical Variability in the Sensory-Evoked Response in Autism.
J Autism Dev Disord
PUBLISHED: 10-20-2014
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Previous findings have shown that individuals with autism spectrum disorder (ASD) evince greater intra-individual variability (IIV) in their sensory-evoked fMRI responses compared to typical control participants. We explore the robustness of this finding with a new sample of high-functioning adults with autism. Participants were presented with visual, somatosensory and auditory stimuli in the scanner whilst they completed a one-back task. While ASD and control participants were statistically indistinguishable with respect to behavioral responses, the new ASD group exhibited greater IIV relative to controls. We also show that the IIV was equivalent across hemispheres and remained stable over the duration of the experiment. This suggests that greater cortical IIV may be a replicable characteristic of sensory systems in autism.
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Anatomical Abnormalities in Autism?
Cereb. Cortex
PUBLISHED: 10-16-2014
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Substantial controversy exists regarding the presence and significance of anatomical abnormalities in autism spectrum disorders (ASD). The release of the Autism Brain Imaging Data Exchange (?1000 participants, age 6-65 years) offers an unprecedented opportunity to conduct large-scale comparisons of anatomical MRI scans across groups and to resolve many of the outstanding questions. Comprehensive univariate analyses using volumetric, thickness, and surface area measures of over 180 anatomically defined brain areas, revealed significantly larger ventricular volumes, smaller corpus callosum volume (central segment only), and several cortical areas with increased thickness in the ASD group. Previously reported anatomical abnormalities in ASD including larger intracranial volumes, smaller cerebellar volumes, and larger amygdala volumes were not substantiated by the current study. In addition, multivariate classification analyses yielded modest decoding accuracies of individuals' group identity (<60%), suggesting that the examined anatomical measures are of limited diagnostic utility for ASD. While anatomical abnormalities may be present in distinct subgroups of ASD individuals, the current findings show that many previously reported anatomical measures are likely to be of low clinical and scientific significance for understanding ASD neuropathology as a whole in individuals 6-35 years old.
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Size Precedes View: Developmental Emergence of Invariant Object Representations in Lateral Occipital Complex.
J Cogn Neurosci
PUBLISHED: 09-23-2014
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Although object perception involves encoding a wide variety of object properties (e.g., size, color, viewpoint), some properties are irrelevant for identifying the object. The key to successful object recognition is having an internal representation of the object identity that is insensitive to these properties while accurately representing important diagnostic features. Behavioral evidence indicates that the formation of these kinds of invariant object representations takes many years to develop. However, no work has investigated the developmental emergence of invariant object representations in the ventral visual processing stream, particularly in the lateral occipital complex (LOC) that is implicated in object processing in adults. Here, we used an fMR adaptation paradigm to evaluate age-related changes in the neural representation of objects within LOC across variations in size and viewpoint from childhood through early adulthood. We found a dissociation between the neural encoding of object size and object viewpoint within LOC: by age of 5-10 years, area LOC demonstrates adaptation across changes in size, suggesting that LOC responses are invariant to size variations, but that adaptation across changes in view is observed in LOC much later in development. Furthermore, activation in LOC was correlated with behavioral indicators of view invariance across the entire sample, such that greater adaptation was correlated with better recognition of objects across changes in viewpoint. We did not observe similar developmental differences within early visual cortex. These results indicate that LOC acquires the capacity to compute invariance specific to different sources of information at different time points over the course of development.
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A comparison of methods used to evaluate mobility performance in the visually impaired.
Br J Ophthalmol
PUBLISHED: 08-19-2014
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To compare three different approaches to measuring mobility performance when evaluating the visually impaired.
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Beneficial effect of a high number of copies of salivary amylase AMY1 gene on obesity risk in Mexican children.
Diabetologia
PUBLISHED: 08-14-2014
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Childhood obesity is a major public health problem in Mexico, affecting one in every three children. Genome-wide association studies identified genetic variants associated with childhood obesity, but a large missing heritability remains to be elucidated. We have recently shown a strong association between a highly polymorphic copy number variant encompassing the salivary amylase gene (AMY1 also known as AMY1A) and obesity in European and Asian adults. In the present study, we aimed to evaluate the association between AMY1 copy number and obesity in Mexican children.
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The morbidity and mortality conference as an adverse event surveillance tool in a paediatric intensive care unit.
BMJ Qual Saf
PUBLISHED: 07-18-2014
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To determine if standardised chart review applied to records of patients discussed at a paediatric intensive care unit (PICU) morbidity and mortality conference (MMC) yields additional or different information regarding safety event occurrence and characteristics.
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Ranibizumab Versus Mitomycin C in Primary Trabeculectomy - A Pilot Study.
Curr. Eye Res.
PUBLISHED: 07-15-2014
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ABSTRACT Purpose: The current standard adjunctive agent used in primary trabeculectomy is mitomycin C (MMC), but it is associated with well known complications. The objective of this study is to test the feasibility of the anti-vascular endothelial growth factor (anti-VEGF) agent ranibizumab for adjunctive use instead of MMC (0.4?mg/ml). Materials and methods: A prospective, randomized open label study of 24 consecutive patients undergoing primary trabeculectomy at the Wills Eye Institute Glaucoma Service from March 2008 through February 2010 was conducted. Twenty-four eyes were included in the study and clinical outcomes were examined. Results: There were no significant differences in baseline demographic or clinical characteristics between the ranibizumab and MMC groups. Nine of the 12 ranibizumab patients completed the 1 year study. Three subjects required tube shunt surgery and were removed from the study. Eleven of 12 MMC patients completed the study (one underwent hip surgery and was lost to follow-up). Mean intra-ocular pressure (IOP) was significantly higher in the ranibizumab arm at 1 month (p?=?0.002). Bleb extent was significantly less in the ranibizumab arm at 6 months (p?=?0.006). Patients in the ranibizumab arm required more hypotensive medication at month 3 (p?=?0.011). Conclusions: Although there was no IOP difference or difference in medication use between the two treatment groups at one year, more patients in the ranibizumab group required additional glaucoma surgery during the study period.
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Interventions to reduce pediatric medication errors: a systematic review.
Pediatrics
PUBLISHED: 07-14-2014
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Medication errors cause appreciable morbidity and mortality in children. The objective was to determine the effectiveness of interventions to reduce pediatric medication errors, identify gaps in the literature, and perform meta-analyses on comparable studies.
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The morbidity and mortality conference in PICUs in the United States: a national survey*.
Crit. Care Med.
PUBLISHED: 07-12-2014
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Determine how many morbidity and mortality conferences in PICUs across the United States conform to key elements of medical incident analysis.
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Acute loss of Cited2 impairs Nanog expression and decreases self-renewal of mouse embryonic stem cells.
Stem Cells
PUBLISHED: 07-10-2014
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Identifying novel players of the pluripotency gene regulatory network centred on Oct4, Sox2 and Nanog, as well as delineating the interactions within the complex network are key to understanding self-renewal and early cell fate commitment of embryonic stem cells (ESC). While overexpression of the transcriptional regulator Cited2 sustains ESC pluripotency, its role in ESC functions remains unclear. Here, we show that Cited2 is important for proliferation, survival and self-renewal of mouse ESC. We position Cited2 within the pluripotency gene regulatory network by defining Nanog, Tbx3 and Klf4 as its direct targets. We also demonstrate that the defects caused by Cited2 depletion are, at least in part, rescued by Nanog constitutive expression. Finally, we demonstrate that Cited2 is required for and enhances reprogramming of mouse embryonic fibroblasts (MEFs) to induced pluripotent stem (iPS) cells. Stem Cells 2014.
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Heterogeneity of breast cancer clinical characteristics and outcome in US black women--effect of place of birth.
Breast J
PUBLISHED: 07-08-2014
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Breast cancer mortality in black women is disproportionately high; reasons for this phenomenon are still unclear. In addition to socioeconomic factors, the biology of the tumor may play a role. We analyzed 1,097 incident invasive breast cancer cases diagnosed between 2000 and 2010 in black US women from Long Island and Brooklyn. Thirty-five percent of women had an estrogen receptor (ER) negative tumor, 46% a progesterone receptor (PR) negative tumor. ER, PR negative tumors were diagnosed at an earlier age (55.8 versus 55.3 years), at a later stage (p = 0.06), were larger in size (p = 0.04), and more frequently treated with neo-adjuvant chemotherapy (p = 0.06) than ER, PR positive tumors. Determinants of shorter survival were: ER, PR negativity (HR: 2.2, 95% CI: 1.4-3.4), age, and stage at diagnosis (HR: 2.0; 95% CI: 1.5-2.7). ER, PR negative breast cancer born outside of the US experienced a significantly worse survival than ER, PR negative women who were born in the US. ER, PR negative tumors in black women born outside the US, mainly in the Caribbean, are biologically more aggressive than the same size and age-matched tumors in black women born in the US. Our study suggests that environmental exposures in the country of origin may impact on host cancer interactions and cancer outcome.
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Attentional dynamics mediated by subcortical mechanisms.
Atten Percept Psychophys
PUBLISHED: 07-02-2014
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Following a salient cue that attracts attention to a specific spatial location, perceptual processing of information at that location is facilitated if the interval between the cue and target is brief, or, is inhibited if the interval between the cue and target is long. The mechanisms mediating these attentional dynamics continue to be the subject on ongoing debate. On one classic account, facilitation and inhibition of return (IOR) are two ends of a continuum, generated by the same underlying mechanism. Other accounts have postulated that these two attentional processes emerge from independent systems. To address these alternatives, we report data from three experiments in which a cue and its ensuing target are presented to the same or different eyes at varying cue-target intervals. Whereas the onset of facilitation was apparent earlier when the cue and target shared the eye-of-origin, the onset of IOR was not affected by the eye to which the cue and target were presented. This finding implicates at least some, if not full, independence in the system(s) that give rise to attentional facilitation and IOR, and, moreover, suggests that facilitation may be more reliant on subcortical levels of the visual pathways than IOR.
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Process engineering for bioflavour production with metabolically active yeast - a minireview.
Yeast
PUBLISHED: 06-30-2014
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Flavours are biologically active molecules of large commercial interest in the food, cosmetics, detergent and pharmaceutical industry. The production of flavours can take place by either extraction from plant materials, chemical synthesis, through biological conversion of precursor molecules or through de novo biosynthesis. The latter alternatives are gaining importance through the rapidly growing fields of systems biology and metabolic engineering giving efficient production hosts for the so-called "bioflavours", which are natural flavour and/or fragrance compounds obtained with cell factories or enzymatic systems. One potential production host for bioflavour is yeast. In this mini-review, we give an overview of bioflavour production in yeast from the process engineering perspective. Two specific examples - production of 2-phenylethanol and vanillin - are used to illustrate process challenges and strategies used. Copyright © 2014 John Wiley & Sons, Ltd.
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Women's health in spaceflight.
Aviat Space Environ Med
PUBLISHED: 06-13-2014
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To review the current state of knowledge with regards to clinical challenges related to women's health during spaceflight.
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Design of the standardizing care to improve outcomes in pediatric end stage renal disease collaborative.
Pediatr. Nephrol.
PUBLISHED: 06-12-2014
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The Standardizing Care to Improve Outcomes in Pediatric End Stage Renal Disease (SCOPE) Collaborative is a North American multi-center quality transformation effort whose primary aim is to minimize exit-site infection and peritonitis rates among pediatric chronic peritoneal dialysis patients. The project, developed by the quality improvement faculty and staff at the Children's Hospital Association's Quality Transformation Network (QTN) and content experts in pediatric nephrology and pediatric infectious diseases, is modeled after the QTN's highly successful Pediatric Intensive Care Unit and Hematology-Oncology central line-associated blood-stream infection (CLABSI) Collaboratives. Like the Association's other QTN efforts, the SCOPE Collaborative is part of a broader effort to assist pediatric nephrology teams in learning about and using quality improvement methods to develop and implement evidence-based practices. In addition, the design of this project allows for targeted research that builds on high-quality, ongoing data collection. Finally, the project, while focused on reducing peritoneal dialysis catheter-associated infections, will also serve as a model for future pediatric nephrology projects that could further improve the quality of care provided to children with end stage renal disease.
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Impairment of the face processing network in congenital prosopagnosia.
Front Biosci (Elite Ed)
PUBLISHED: 06-05-2014
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The goal of the current paper is to review recent findings concerning the neural basis of congenital prosopagnosia (CP), a lifelong impairment in face processing that occurs in the absence of explicit brain damage. As such, CP offers a unique model for exploring the psychological and neural bases of normal face processing. We start by providing background about face perception and representation, and then review behavioral evidence gleaned from individuals with CP. We then review recent functional and structural neural investigations which offer a comprehensive account of the mechanisms underlying CP and support a characterization of this impairment as a disconnection syndrome rather than as a syndrome related to focal brain malfunction. We end the paper by offering a general framework for CP which, we believe, best integrates the behavioral and neural findings, and offers a platform for generating hypotheses for future studies. There remain many open issues in our understanding of CP and, to address these unanswered questions, we lay out several future research directions and testable hypotheses for further investigation.
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Comparing Gonioscopy With Visante and Cirrus Optical Coherence Tomography for Anterior Chamber Angle Assessment in Glaucoma Patients.
J. Glaucoma
PUBLISHED: 05-22-2014
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The aim of this study was to compare gonioscopy with Visante and Cirrus optical coherence tomography (OCT) for identifying angle structures and the presence of angle closure in patients with glaucoma. A secondary objective was to assess interrater agreement for gonioscopy grading among 3 independent examiners.
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From word superiority to word inferiority: visual processing of letters and words in pure alexia.
Cogn Neuropsychol
PUBLISHED: 05-07-2014
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Visual processing and naming of individual letters and short words were investigated in four patients with pure alexia. To test processing at different levels, the same stimuli were studied across a naming task and a visual perception task. The normal word superiority effect was eliminated in both tasks for all patients, and this pattern was more pronounced in the more severely affected patients. The relationship between performance with single letters and words was, however, not straightforward: One patient performed within the normal range on the letter perception task, while being severely impaired in letter naming and word processing, and performance with letters and words was dissociated in all four patients, with word reading being more severely impaired than letter recognition. This suggests that the word reading deficit in pure alexia may not be reduced to an impairment in single letter perception.
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Associations of neighborhood concentrated poverty, neighborhood racial/ethnic composition, and indoor allergen exposures: a cross-sectional analysis of los angeles households, 2006-2008.
J Urban Health
PUBLISHED: 04-29-2014
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Although racial/ethnic, socioeconomic, and neighborhood factors have been linked to asthma, and the association between indoor allergens and asthma is well documented, few studies have examined the relationship between these factors and indoor allergens. We examined the frequency of reported indoor allergens and differences by racial/ethnic, socioeconomic, and neighborhood characteristics among a diverse sample of Los Angeles households. Multilevel logistic regression models were used to analyze the data from 723 households from wave 2 of the Los Angeles Family and Neighborhood Survey. The reported presence of rats, mice, cockroaches, mold, pets, and tobacco smoke were the primary outcomes of interest. Hispanic and Asian households had a nearly threefold increase in the odds of reporting cockroaches compared to non-Hispanic Whites (OR, 2.85; 95 % CI 1.38-5.88 and OR, 2.62; 95 % CI 1.02-6.73, respectively) even after adjusting for socioeconomic factors. Primary caregivers who had obtained a high school degree were significantly less likely to report the presence of mice and cockroaches compared to primary caregivers with less than a high school degree (OR, 0.19; 95 % CI 0.08-0.46 and OR, 0.39; 95 % CI 0.23-0.68, respectively). Primary caregivers with more than a high school degree were also less likely to report the presence of rats, mice, and cockroaches within their households, compared to those with less than a high school degree. Compared to renters, home owners were less likely to report the presence of mice, cockroaches, and mold within their households. At the neighborhood level, households located within neighborhoods of high concentrated poverty (where the average poverty rate is at least 50 %) were more likely to report the presence of mice and cockroaches compared to households in low concentrated poverty neighborhoods (average poverty rate is 10 % or less), after adjusting for individual race/ethnicity and socioeconomic characteristics. Our study found evidence in support of neighborhood-level racial/ethnic and socioeconomic influences on indoor allergen exposure, above and beyond individual factors. Future studies should continue to explore individual and neighborhood-level racial/ethnic and socioeconomic differences in household allergen exposures across diverse contexts.
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Effects of a TAFI-Inhibitor Combined with a Suboptimal Dose of rtPA in a Murine Thromboembolic Model of Stroke.
Cerebrovasc. Dis.
PUBLISHED: 04-22-2014
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Background: Since thrombolysis is the only approved intervention for ischemic stroke, improving its efficacy and safety is a therapeutic aim of considerable interest. The activated form of thrombin activatable fibrinolysis inhibitor (TAFI) has antifibrinolytic effects, and inhibition of TAFI might thus favor recanalization. The present study compared efficacy between TAFI inhibition alone and TAFI inhibition in combination with rtPA at a suboptimal dose, in a murine model of thromboembolic stroke. Methods: Focal ischemia was induced in mice by thrombin injection in the middle cerebral artery. Animals were placed within the magnet immediately after surgery for baseline MRI (H0). MRI examination comprised diffusion-weighted imaging (DWI), perfusion-weighted imaging (PWI), and T2-weighted imaging (T2-WI). Animals were randomly assigned to 1 of 5 treatment groups: saline, rtPA 5 mg/kg (tPA(5): suboptimal or low dose), rtPA 10 mg/kg (tPA(10): standard dose), TAFI-I 100 mg/kg (TAFI-I), and rtPA 5 mg/kg + TAFI-I 100 mg/kg (tPA(5) + TAFI-I). Treatments were administered inside the magnet, via a catheter placed in the tail vein, using a power injector, as 10% bolus and 90% infusion over a period of 20 min. MRI examination was repeated at 3 h (H3) and 24 h (H24) after surgery. Therapeutic benefit was evaluated by: (1) improvement of reperfusion and (2) reduction in final lesion size. Microhemorrhages were assessed as black spots on T2-WI at H24. Animals were sacrificed after the last MR examination. The surgeon and all investigators were blinded to treatment allocation. Results: A total of 104 mice were operated on. Forty four of these were excluded from the study and 27 from the analysis, according to a priori defined criteria (no lesion or no mismatch), leading to the following distribution: saline (n = 6), tPA(5) (n = 8), tPA(10) (n = 7), TAFI-I (n = 7), and TAFI-I + tPA(5) (n = 5). Standard-dose rtPA treatment (tPA(10)) significantly improved lesion regression between H0 and H24 compared to saline (-57 ± 18% vs. -36 ± 21%, p = 0.03), which treatment with rtPA(5) or TAFI-I alone did not. On the other hand, combined treatment with tPA(5) + TAFI-I showed only a trend toward lesion regression (-49 ± 26%), similarly to treatment with tPA(10), but not significantly different from saline (p = 0.46). Nine animals showed microhemorrhage on T2-WI at H24. These animals were evenly distributed between groups. Conclusions: The present study showed that the combination of TAFI-I with a suboptimal dose of rtPA is not as effective as the standard dose of rtPA, while TAFI inhibition alone is not effective at all. The thromboembolic model is of particular interest in assessing rtPA association to improve thrombolysis, especially when coupled with longitudinal MRI assessment. © 2014 S. Karger AG, Basel.
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An ERP investigation of the co-development of hemispheric lateralization of face and word recognition.
Neuropsychologia
PUBLISHED: 04-03-2014
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The adult human brain would appear to have specialized and independent neural systems for the visual processing of words and faces. Extensive evidence has demonstrated greater selectivity for written words in the left over right hemisphere, and, conversely, greater selectivity for faces in the right over left hemisphere. This study examines the emergence of these complementary neural profiles, as well as the possible relationship between them. Using behavioral and neurophysiological measures, in adults, we observed the standard finding of greater accuracy and a larger N170 ERP component in the left over right hemisphere for words, and conversely, greater accuracy and a larger N170 in the right over the left hemisphere for faces. We also found that although children aged 7-12 years revealed the adult hemispheric pattern for words, they showed neither a behavioral nor a neural hemispheric superiority for faces. Of particular interest, the magnitude of their N170 for faces in the right hemisphere was related to that of the N170 for words in their left hemisphere. These findings suggest that the hemispheric organization of face recognition and of word recognition does not develop independently, and that word lateralization may precede and drive later face lateralization. A theoretical account for the findings, in which competition for visual representations unfolds over the course of development, is discussed.
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Sepsis in old age: review of human and animal studies.
Aging Dis
PUBLISHED: 04-01-2014
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Sepsis is a serious problem among the geriatric population as its incidence and mortality rates dramatically increase with advanced age. Despite a large number of ongoing clinical and basic research studies, there is currently no effective therapeutic strategy that rescues elderly patients with severe sepsis. Recognition of this problem is relatively low as compared to other age-associated diseases. The disparity between clinical and basic studies is a problem, and this is likely due, in part, to the fact that most laboratory animals used for sepsis research are not old while the majority of sepsis cases occur in the geriatric population. The objective of this article is to review recent epidemiological studies and clinical observations, and compare these with findings from basic laboratory studies which have used aged animals in experimental sepsis.
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State-Mandated Hospital Infection Reporting Is Not Associated With Decreased Pediatric Health Care-Associated Infections.
J Patient Saf
PUBLISHED: 04-01-2014
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State governments increasingly mandate public reporting of central line-associated blood stream infections (CLABSIs). This study tests if hospitals located in states with state-mandated, facility-identified, pediatric-specific public CLABSI reporting have lower rates of CLABSIs as defined by the Agency for Healthcare Research and Quality's Pediatric Quality Indicator 12 (PDI12).
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Low copy number of the salivary amylase gene predisposes to obesity.
Nat. Genet.
PUBLISHED: 03-06-2014
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Common multi-allelic copy number variants (CNVs) appear enriched for phenotypic associations compared to their biallelic counterparts. Here we investigated the influence of gene dosage effects on adiposity through a CNV association study of gene expression levels in adipose tissue. We identified significant association of a multi-allelic CNV encompassing the salivary amylase gene (AMY1) with body mass index (BMI) and obesity, and we replicated this finding in 6,200 subjects. Increased AMY1 copy number was positively associated with both amylase gene expression (P = 2.31 × 10(-14)) and serum enzyme levels (P < 2.20 × 10(-16)), whereas reduced AMY1 copy number was associated with increased BMI (change in BMI per estimated copy = -0.15 (0.02) kg/m(2); P = 6.93 × 10(-10)) and obesity risk (odds ratio (OR) per estimated copy = 1.19, 95% confidence interval (CI) = 1.13-1.26; P = 1.46 × 10(-10)). The OR value of 1.19 per copy of AMY1 translates into about an eightfold difference in risk of obesity between subjects in the top (copy number > 9) and bottom (copy number < 4) 10% of the copy number distribution. Our study provides a first genetic link between carbohydrate metabolism and BMI and demonstrates the power of integrated genomic approaches beyond genome-wide association studies.
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Clinical correlates of red blood cell omega-3 fatty acid content in male veterans with peripheral arterial disease.
J. Vasc. Surg.
PUBLISHED: 03-04-2014
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Despite available medical therapies, patients with peripheral arterial disease (PAD) remain at high risk for cardiovascular events. The n-3 polyunsaturated fatty acids (PUFA), derived from marine sources, have been shown to improve cardiovascular mortality. The Omega-3 Index (O3I), a proportion of the n-3 PUFA eicosapentaenoic acid and docosahexaenoic acid in the red blood cell membrane, correlates with cardiovascular risk. Previous investigations have found that n-3 PUFA supplementation, fish consumption, older age, and smoking history affect the O3I in different patient populations, although similar correlations have never been explored in PAD. We hypothesized that in our PAD cohort, blood content of omega-3 fatty acids would directly and positively correlate with a history of fish oil supplementation and older age and inversely correlate with a smoking history and obesity.
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Peripheral arterial disease, gender, and depression in the Heart and Soul Study.
J. Vasc. Surg.
PUBLISHED: 02-06-2014
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Despite the high prevalence of peripheral arterial disease (PAD) in women, risk factors for PAD in women are not well understood.
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Fish genomes provide novel insights into the evolution of vertebrate secretin receptors and their ligand.
Gen. Comp. Endocrinol.
PUBLISHED: 02-04-2014
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The secretin receptor (SCTR) is a member of Class 2 subfamily B1 GPCRs and part of the PAC1/VPAC receptor subfamily. This receptor has long been known in mammals but has only recently been identified in other vertebrates including teleosts, from which it was previously considered to be absent. The ligand for SCTR in mammals is secretin (SCT), an important gastrointestinal peptide, which in teleosts has not yet been isolated, or the gene identified. This study revises the evolutionary model previously proposed for the secretin-GPCRs in metazoan by analysing in detail the fishes, the most successful of the extant vertebrates. All the Actinopterygii genomes analysed and the Chondrichthyes and Sarcopterygii fish possess a SCTR gene that shares conserved sequence, structure and synteny with the tetrapod homologue. Phylogenetic clustering and gene environment comparisons revealed that fish and tetrapod SCTR shared a common origin and diverged early from the PAC1/VPAC subfamily group. In teleosts SCTR duplicated as a result of the fish specific whole genome duplication but in all the teleost genomes analysed, with the exception of tilapia (Oreochromis niloticus), one of the duplicates was lost. The function of SCTR in teleosts is unknown but quantitative PCR revealed that in both sea bass (Dicentrarchus labrax) and tilapia (Oreochromis mossambicus) transcript abundance is high in the gastrointestinal tract suggesting it may intervene in similar processes to those in mammals. In contrast, no gene encoding the ligand SCT was identified in the ray-finned fishes (Actinopterygii) although it was present in the coelacanth (lobe finned fish, Sarcopterygii) and in the elephant shark (holocephalian). The genes in linkage with SCT in tetrapods and coelacanth were also identified in ray-finned fishes supporting the idea that it was lost from their genome. At present SCTR remains an orphan receptor in ray-finned fishes and it will be of interest in the future to establish why SCT was lost and which ligand substitutes for it so that full characterization of the receptor can occur.
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Anxiety disorders during pregnancy: a systematic review.
J Clin Psychiatry
PUBLISHED: 02-03-2014
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To systematically evaluate the literature on anxiety disorders during pregnancy.
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Women with malignant pleural mesothelioma have a threefold better survival rate than men.
Ann. Thorac. Surg.
PUBLISHED: 01-27-2014
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Many studies have reported that women with malignant pleural mesothelioma (MPM) experience longer survival compared with men, whereas others have not. To date, no large population-based studies have evaluated MPM outcome and its determinants in female patients.
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Alternative human liver transcripts of TCF7L2 bind to the gluconeogenesis regulator HNF4? at the protein level.
Diabetologia
PUBLISHED: 01-26-2014
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Gene polymorphisms of TCF7L2 are associated with increased risk of type 2 diabetes and transcription factor 7-like 2 (TCF7L2) plays a role in hepatic glucose metabolism. We therefore addressed the impact of TCF7L2 isoforms on hepatocyte nuclear factor 4? (HNF4?) and the regulation of gluconeogenesis genes.
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Minimizing the invasiveness of traditional trabeculectomy surgery.
J Cataract Refract Surg
PUBLISHED: 01-16-2014
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Microinvasive invasive glaucoma surgery has become increasingly popular as a surgical alternative for glaucoma. Although the time-honored trabeculectomy remains the unrivaled contender for lowering intraocular pressure (IOP) into the single digits, newer devices are available that attempt to reach similar IOP levels with fewer complications and quicker visual recovery. The Express mini-shunt and the Innfocus microshunt are 2 devices that bring us closer to the goal of repeatable, lower risk surgery; improved patient satisfaction; stabilization of the visual field; and long-term IOP control. The mini-shunt has been approved by the U.S. Food and Drug Administration, while the microshunt is still under review.
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Short-term physical inactivity impairs vascular function.
J. Surg. Res.
PUBLISHED: 01-16-2014
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Sedentarism, also termed physical inactivity, is an independent risk factor for cardiovascular diseases. Mechanisms thought to be involved include insulin resistance, dyslipidemia, hypertension, and increased inflammation. It is unknown whether changes in vascular and endothelial function also contribute to this excess risk. We hypothesized that short-term exposure to inactivity would lead to endothelial dysfunction, arterial stiffening, and increased vascular inflammation.
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Walking disability in patients with peripheral artery disease is associated with arterial endothelial function.
J. Vasc. Surg.
PUBLISHED: 01-11-2014
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Patients with peripheral artery disease (PAD) have varying degrees of walking disability that do not completely correlate with ankle-brachial index (ABI) or angiographic anatomy. We hypothesized that endothelial function (EF) is an independent predictor of symptom severity in PAD patients.
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Safety and feasibility of adjunctive dexamethasone infusion into the adventitia of the femoropopliteal artery following endovascular revascularization.
J. Vasc. Surg.
PUBLISHED: 01-11-2014
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Restenosis following endovascular treatment of the femoropopliteal segment is associated with the inflammatory response produced in the artery wall at the time of the procedure. Although local drug delivery to the superficial femoral and popliteal arteries promises improved patency, data are currently limited. We hypothesized that improved percutaneous delivery of an anti-inflammatory compound into the adventitia of the femoropopliteal at the time of endovascular treatment would be safe, feasible, and decrease the inflammatory response.
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Intracameral triamcinolone acetonide in glaucoma surgery: a prospective randomized controlled trial.
Am. J. Ophthalmol.
PUBLISHED: 01-09-2014
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To evaluate the efficacy and safety of intracameral triamcinolone acetonide (TA) in glaucoma surgery.
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The nature of face representations in subcortical regions.
Neuropsychologia
PUBLISHED: 01-08-2014
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Studies examining the neural correlates of face perception in humans have focused almost exclusively on the distributed cortical network of face-selective regions. Recently, however, investigations have also identified subcortical correlates of face perception and the question addressed here concerns the nature of these subcortical face representations. To explore this issue, we presented to participants pairs of images sequentially to the same or to different eyes. Superior performance in the former over latter condition implicates monocular, prestriate portions of the visual system. Over a series of five experiments, we manipulated both lower-level (size, location) as well as higher-level (identity) similarity across the pair of faces. A monocular advantage was observed even when the faces in a pair differed in location and in size, implicating some subcortical invariance across lower-level image properties. A monocular advantage was also observed when the faces in a pair were two different images of the same individual, indicating the engagement of subcortical representations in more abstract, higher-level aspects of face processing. We conclude that subcortical structures of the visual system are involved, perhaps interactively, in multiple aspects of face perception, and not simply in deriving initial coarse representations.
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Revisiting the Hispanic Health Paradox: The Relative Contributions of Nativity, Country of Origin, and Race/Ethnicity to Childhood Asthma.
J Immigr Minor Health
PUBLISHED: 01-02-2014
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This study examined the relationship between race and Hispanic ethnicity, maternal and child nativity, country of origin and asthma among 2,558 non-Hispanic white and Hispanic children across 65 Los Angeles neighborhoods. A series of two-level multilevel models were estimated to examine the independent effects of race, ethnicity, and country of origin on childhood asthma. Lifetime asthma prevalence was reported among 9 % of children, with no significant differences between Hispanics and non-Hispanic whites overall. However, in fully adjusted models, Hispanic children of non-Mexican origin reported higher odds of asthma compared to non-Hispanic white children. A protective nativity effect was also observed among children of foreign born mothers compared to US born mothers. Our study provides evidence in support of the heterogeneity of childhood asthma by Hispanic ethnicity and maternal nativity. These findings suggest moving beyond solely considering racial/ethnic classifications which could mask subgroups at increased risk of childhood asthma.
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Stunting, Poor Iron Status and Parasite Infection Are Significant Risk Factors for Lower Cognitive Performance in Cambodian School-Aged Children.
PLoS ONE
PUBLISHED: 01-01-2014
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Nutrition is one of many factors affecting the cognitive development of children. In Cambodia, 55% of children <5 y were anemic and 40% stunted in 2010. Currently, no data exists on the nutritional status of Cambodian school-aged children, or on how malnutrition potentially affects their cognitive development.
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Average Values and Racial Differences of Neutrophil Lymphocyte Ratio among a Nationally Representative Sample of United States Subjects.
PLoS ONE
PUBLISHED: 01-01-2014
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Several studies reported the negative impact of elevated neutrophil/lymphocyte ratio (NLR) on outcomes in many surgical and medical conditions. Previous studies used arbitrary NLR cut-off points according to the average of the populations under study. There is no data on the average NLR in the general population. The aim of this study is to explore the average values of NLR and according to race in adult non-institutional United States individuals by using national data.
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Impaired holistic processing of left-right composite faces in congenital prosopagnosia.
Front Hum Neurosci
PUBLISHED: 01-01-2014
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Congenital prosopagnosia (CP) refers to a lifelong impairment in face processing despite normal visual and intellectual skills. Many studies have suggested that the key underlying deficit in CP is one of a failure to engage holistic processing. Moreover, there has been some suggestion that, in normal observers, there may be greater involvement of the right than left hemisphere in holistic processing. To examine the proposed deficit in holistic processing and its potential hemispheric atypicality in CP, we compared the performance of 8 CP individuals with both matched controls and a large group of non-matched controls on a novel, vertical composite task. In this task, participants judged whether a cued half of a face (either left or right half) was the same or different at study and test, and the two face halves could be either aligned or misaligned. The standard index of holistic processing is one in which the unattended face half influences performance on the cued half and this influence is greater in the aligned than in the misaligned condition. Relative to controls, the CP participants, both at a group and at an individual level, did not show holistic processing in the vertical composite task. There was also no difference in performance as a function of hemifield of the cued face half in the CP individuals, and this was true in the control participants, as well. The findings clearly confirm the deficit in holistic processing in CP and reveal the useful application of this novel experimental paradigm to this population and potentially to others as well.
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Perceptions of neighborhood safety and asthma among children and adolescents in Los Angeles: a multilevel analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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Research examining the impact of neighborhoods on asthma has shown an increased interest in the role of the psychosocial environment. We examined the associations between various measures of neighborhood safety, individual and family characteristics, and asthma outcomes among children in Los Angeles.
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Exogenous spatial attention: Evidence for intact functioning in adults with autism spectrum disorder.
J Vis
PUBLISHED: 12-12-2013
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Deficits or atypicalities in attention have been reported in individuals with autism spectrum disorder (ASD), yet no consensus on the nature of these deficits has emerged. We conducted three experiments that paired a peripheral precue with a covert discrimination task, using protocols for which the effects of covert exogenous spatial attention on early vision have been well established in typically developing populations. Experiment 1 assessed changes in contrast sensitivity, using orientation discrimination of a contrast-defined grating; Experiment 2 evaluated the reduction of crowding in the visual periphery, using discrimination of a letter-like figure with flanking stimuli at variable distances; and Experiment 3 assessed improvements in visual search, using discrimination of the same letter-like figure with a variable number of distractor elements. In all three experiments, we found that exogenous attention modulated visual discriminability in a group of high-functioning adults with ASD and that it did so in the same way and to the same extent as in a matched control group. We found no evidence to support the hypothesis that deficits in exogenous spatial attention underlie the emergence of core ASD symptomatology.
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Monocular Advantage for Face Perception Implicates Subcortical Mechanisms in Adult Humans.
J Cogn Neurosci
PUBLISHED: 11-18-2013
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The ability to recognize faces accurately and rapidly is an evolutionarily adaptive process. Most studies examining the neural correlates of face perception in adult humans have focused on a distributed cortical network of face-selective regions. There is, however, robust evidence from phylogenetic and ontogenetic studies that implicate subcortical structures, and recently, some investigations in adult humans indicate subcortical correlates of face perception, as well. The questions addressed here are whether low-level subcortical mechanisms for face perception (in the absence of changes in expression) are conserved in human adults, and if so, what is the nature of these subcortical representations. In a series of four experiments, we presented pairs of images to the same or different eyes. Participants performance demonstrated that subcortical mechanisms, indexed by monocular portions of the visual system, play a functional role in face perception. These mechanisms are sensitive to face-like configurations and afford a coarse representation of a face, comprised of primarily low spatial frequency information, which suffices for matching faces but not for more complex aspects of face perception such as sex differentiation. Importantly, these subcortical mechanisms are not implicated in the perception of other visual stimuli, such as cars or letter strings. These findings suggest a conservation of phylogenetically and ontogenetically lower-order systems in adult human face perception. The involvement of subcortical structures in face recognition provokes a reconsideration of current theories of face perception, which are reliant on cortical level processing, inasmuch as it bolsters the cross-species continuity of the biological system for face recognition.
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Information-based analysis of X-ray in-line phase tomography with application to the detection of iron oxide nanoparticles in the brain.
Opt Express
PUBLISHED: 11-13-2013
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The study analyzes noise in X-ray in-line phase tomography in a biomedical context. The impact of noise on detection of iron oxide nanoparticles in mouse brain is assessed. The part of the noise due to the imaging system and the part due to biology are quantitatively expressed in a Neyman Pearson detection strategy with two models of noise. This represents a practical extension of previous work on noise in phase-contrast X-ray imaging which focused on the theoretical expression of the signal-to-noise ratio in mono-dimensional phantoms, taking account of the statistical noise of the imaging system only. We also report the impact of the phase retrieval step on detection performance. Taken together, this constitutes a general methodology of practical interest for quantitative extraction of information from X-ray in-line phase tomography, and is also relevant to assessment of contrast agents with a blob-like signature in high resolution imaging.
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Breast Cancer Clinical Characteristics and Outcomes in Trinidad and Tobago.
J Immigr Minor Health
PUBLISHED: 10-23-2013
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Trinidad and Tobago (TT) is the country with the highest breast cancer mortality in the Caribbean. It is unknown whether biological, behavioral, environmental, or clinical factors play a significant role in such outcome. A total of 2,614 incident cases, histologically confirmed and recorded in the TT cancer registries between 1995 and 2005, with follow-up through 2009 were analyzed. Half of the cases were diagnosed between the ages of 40-59 years, 12.5 % before the age of 40 years; 45 % of women were diagnosed at localized stage and 43.7 % were hormone receptor positive. Women diagnosed with distant staging were more likely to undergo chemotherapy compared to those with localized staging (OR 1.39; 95 % CI 1.01-1.89). Hormone receptor negative cases were significantly less likely to undergo radiation or surgery therapy (OR 0.66; 95 % CI 0.56-0.79 and OR 0.67; 95 % CI 0.51-0.88 respectively) compared to those who were hormone receptor positive, but more than 1.5 times as likely to undergo chemotherapy. In multivariate analyses, advanced stage disease and negative hormone receptor status were independently significantly associated with poorer survival outcome. No racial/ethnic differences were observed with respect to treatment or survival. Although access to breast cancer screening and treatment is free in Trinidad and Tobago, breast cancer diagnosis occurs at advanced stages; use of multimodality therapy as a first course of treatment is low.
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Central line maintenance bundles and CLABSIs in ambulatory oncology patients.
Pediatrics
PUBLISHED: 10-07-2013
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Pediatric oncology patients are frequently managed with central lines as outpatients, and these lines confer significant morbidity in this immune-compromised population. We aimed to investigate whether a multidisciplinary, central line maintenance care bundle reduces central line-associated bloodstream infections (CLABSIs) and bacteremias in ambulatory pediatric oncology patients.
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n-3 Polyunsaturated fatty acids supplementation in peripheral artery disease: the OMEGA-PAD trial.
Vasc Med
PUBLISHED: 09-19-2013
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Despite current consensus guidelines recommending intensive cardiovascular risk factor management for peripheral artery disease (PAD), patients suffering from PAD continue to experience significant morbidity and mortality. This excess morbid burden is at least partially related to impaired vascular function and systemic inflammation. Interventions bridging this gap are critical. Dietary supplementation of n-3 polyunsaturated fatty acids (n-3 PUFA) has been shown to improve endothelial function and reduce inflammation in different cohorts, as well as to decrease cardiovascular events in secondary prevention trials in patients with coronary artery disease. Their effects in the PAD population are, however, less well understood. The OMEGA-PAD trial is a double-blinded, randomized, placebo-controlled trial that examines the impact of a high-dose, short-duration dietary oral supplementation of n-3 PUFA on vascular function and inflammation in patients with established PAD. The purpose of this article is to provide a detailed description of the design and methods of the OMEGA-PAD trial, and a summary of baseline characteristics of the cohort.
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Ventral and dorsal visual stream contributions to the perception of object shape and object location.
J Cogn Neurosci
PUBLISHED: 09-03-2013
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Growing evidence suggests that the functional specialization of the two cortical visual pathways may not be as distinct as originally proposed. Here, we explore possible contributions of the dorsal "where/how" visual stream to shape perception and, conversely, contributions of the ventral "what" visual stream to location perception in human adults. Participants performed a shape detection task and a location detection task while undergoing fMRI. For shape detection, comparable BOLD activation in the ventral and dorsal visual streams was observed, and the magnitude of this activation was correlated with behavioral performance. For location detection, cortical activation was significantly stronger in the dorsal than ventral visual pathway and did not correlate with the behavioral outcome. This asymmetry in cortical profile across tasks is particularly noteworthy given that the visual input was identical and that the tasks were matched for difficulty in performance. We confirmed the asymmetry in a subsequent psychophysical experiment in which participants detected changes in either object location or shape, while ignoring the other, task-irrelevant dimension. Detection of a location change was slowed by an irrelevant shape change matched for difficulty, but the reverse did not hold. We conclude that both ventral and dorsal visual streams contribute to shape perception, but that location processing appears to be essentially a function of the dorsal visual pathway.
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Bringing central line-associated bloodstream infection prevention home: CLABSI definitions and prevention policies in home health care agencies.
Jt Comm J Qual Patient Saf
PUBLISHED: 09-03-2013
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A study was conducted to investigate health care agency central line-associated bloodstream infection (CLABSI) definitions and prevention policies and pare them to the Joint Commission National Patient Safety Goal (NPSG.07.04.01), the Centers for Disease Control and Prevention (CDC) CLABSI prevention recommendations, and a best-practice central line care bundle for inpatients.
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The role of human ventral visual cortex in motion perception.
Brain
PUBLISHED: 08-29-2013
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Visual motion perception is fundamental to many aspects of visual perception. Visual motion perception has long been associated with the dorsal (parietal) pathway and the involvement of the ventral form (temporal) visual pathway has not been considered critical for normal motion perception. Here, we evaluated this view by examining whether circumscribed damage to ventral visual cortex impaired motion perception. The perception of motion in basic, non-form tasks (motion coherence and motion detection) and complex structure-from-motion, for a wide range of motion speeds, all centrally displayed, was assessed in five patients with a circumscribed lesion to either the right or left ventral visual pathway. Patients with a right, but not with a left, ventral visual lesion displayed widespread impairments in central motion perception even for non-form motion, for both slow and for fast speeds, and this held true independent of the integrity of areas MT/V5, V3A or parietal regions. In contrast with the traditional view in which only the dorsal visual stream is critical for motion perception, these novel findings implicate a more distributed circuit in which the integrity of the right ventral visual pathway is also necessary even for the perception of non-form motion.
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Development of an in vitro cell system from zebrafish suitable to study bone cell differentiation and extracellular matrix mineralization.
Zebrafish
PUBLISHED: 08-02-2013
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Abstract Mechanisms of bone formation and skeletal development have been successfully investigated in zebrafish using a variety of in vivo approaches, but in vitro studies have been hindered due to a lack of homologous cell lines capable of producing an extracellular matrix (ECM) suitable for mineral deposition. Here we describe the development and characterization of a new cell line termed ZFB1, derived from zebrafish calcified tissues. ZFB1 cells have an epithelium-like phenotype, grow at 28°C in a regular L-15 medium supplemented with 15% of fetal bovine serum, and are maintained and manipulated using standard methods (e.g., trypsinization, cryopreservation, and transfection). They can therefore be propagated and maintained easily in most cell culture facilities. ZFB1 cells show aneuploidy with 2n=78 chromosomes, indicative of cell transformation. Furthermore, because DNA can be efficiently delivered into their intracellular space by nucleofection, ZFB1 cells are suitable for gene targeting approaches and for assessing gene promoter activity. ZFB1 cells can also differentiate toward osteoblast or chondroblast lineages, as demonstrated by expression of osteoblast- and chondrocyte-specific markers, they exhibit an alkaline phosphatase activity, a marker of bone formation in vivo, and they can mineralize their ECM. Therefore, they represent a valuable zebrafish-derived in vitro system for investigating bone cell differentiation and extracellular matrix mineralization.
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Peripheral artery disease and risk of cardiovascular events in patients with coronary artery disease: insights from the Heart and Soul Study.
Vasc Med
PUBLISHED: 07-08-2013
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Among patients with coronary artery disease (CAD), those with peripheral artery disease (PAD) have a greater vulnerability to cardiovascular (CV) events than those with CAD alone. In a prospective cohort study of patients with CAD, we evaluated potential mechanisms that might explain the adverse CV outcomes associated with PAD. We performed a prospective cohort study of 1018 patients with stable CAD who were recruited from 2000 to 2002. Incident symptomatic PAD events were adjudicated during a follow-up period of 7.2 ± 2.6 years. We used Cox proportional hazards models to evaluate the association between incident symptomatic PAD events and subsequent risk of CV events or death. Models were adjusted for demographics, traditional risk factors, inflammation, insulin resistance and health behaviors. Among the 1018 patients, 50 patients who did not report a history of PAD at baseline suffered incident symptomatic PAD events during the follow-up period. Those patients had a higher risk of subsequent CV events and death compared to those who did not develop PAD. After adjustment for traditional risk factors, symptomatic PAD events remained associated with a 70% increased risk of subsequent CV events (adjusted HR 1.7; 95% CI 1.0, 2.9; p = 0.04) and an 80% increased risk of death (adjusted HR 1.8; 95% CI 1.2, 2.7; p = 0.006). Inflammatory biomarkers were the strongest risk factor contributing to the excess risk. In a contemporary cohort of patients with CAD, incident symptomatic PAD events were associated with an increased risk for subsequent CV events. The increased vulnerability to CV events was partially explained by shared CV risk factors and inflammation.
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Emerging Structure-Function Relations in the Developing Face Processing System.
Cereb. Cortex
PUBLISHED: 06-13-2013
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To evaluate emerging structure-function relations in a neural circuit that mediates complex behavior, we investigated age-related differences among cortical regions that support face recognition behavior and the fiber tracts through which they transmit and receive signals using functional neuroimaging and diffusion tensor imaging. In a large sample of human participants (aged 6-23 years), we derived the microstructural and volumetric properties of the inferior longitudinal fasciculus (ILF), the inferior fronto-occipital fasciculus, and control tracts, using independently defined anatomical markers. We also determined the functional characteristics of core face- and place-selective regions that are distributed along the trajectory of the pathways of interest. We observed disproportionately large age-related differences in the volume, fractional anisotropy, and mean and radial, but not axial, diffusivities of the ILF. Critically, these differences in the structural properties of the ILF were tightly and specifically linked with an age-related increase in the size of a key face-selective functional region, the fusiform face area. This dynamic association between emerging structural and functional architecture in the developing brain may provide important clues about the mechanisms by which neural circuits become organized and optimized in the human cortex.
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Evaluating application of the national healthcare safety network central line-associated bloodstream infection surveillance definition: a survey of pediatric intensive care and hematology/oncology units.
Infect Control Hosp Epidemiol
PUBLISHED: 05-21-2013
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To evaluate the application of the National Healthcare Safety Network (NHSN) central line-associated bloodstream infection (CLABSI) definition in pediatric intensive care units (PICUs) and pediatric hematology/oncology units (PHOUs) participating in a multicenter quality improvement collaborative to reduce CLABSIs; to identify sources of variability in the application of the definition.
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Face-space architectures: evidence for the use of independent color-based features.
Psychol Sci
PUBLISHED: 05-13-2013
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The concept of psychological face space lies at the core of many theories of face recognition and representation. To date, much of the understanding of face space has been based on principal component analysis (PCA); the structure of the psychological space is thought to reflect some important aspects of a physical face space characterized by PCA applications to face images. In the present experiments, we investigated alternative accounts of face space and found that independent component analysis provided the best fit to human judgments of face similarity and identification. Thus, our results challenge an influential approach to the study of human face space and provide evidence for the role of statistically independent features in face encoding. In addition, our findings support the use of color information in the representation of facial identity, and we thus argue for the inclusion of such information in theoretical and computational constructs of face space.
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Randomized, Prospective, Comparative Trial of EX-PRESS Glaucoma Filtration Device versus Trabeculectomy (XVT Study).
Am. J. Ophthalmol.
PUBLISHED: 04-25-2013
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To compare the clinical outcomes of the EX-PRESS glaucoma filtration device placed under a partial-thickness scleral flap with trabeculectomy.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.