Showing papers by "Hospital for Sick Children published in 2011"

HRS/EHRA expert consensus statement on the state of genetic testing for the channelopathies and cardiomyopathies

Abstract: This international consensus statement provides the state of genetic testing for the channelopathies and cardiomyopathies. It summarizes the opinion of the international writing group members based on their own experience and on a general review of the literature with respect to the use and role of genetic testing for these potentially heritable cardiac conditions. This document focuses primarily on the state of genetic testing for the 13 distinct entities detailed and the relative diagnostic, prognostic, and therapeutic impact of the genetic test result for each entity. It does not focus on the therapeutic management of the various channelopathies and cardiomyopathies. Treatment/management issues are only discussed for those diseases (i.e., LQTS, HCM, DCM + CCD, RCM) in which the genetic test result could potentially influence treatment considerations. Writing recommendations for genetic diseases require adaptation of the methodology normally adopted to prepare guidelines for clinical practice. Documents produced by other scientific societies have acknowledged the need to define the criteria used to rank the strength of recommendation for genetic diseases.1 The most obvious difference is that randomized and/or blinded studies do not exist. Instead, most of the available data are derived from registries that have followed patients and recorded outcome information. The authors of this statement have therefore defined specific criteria for Class I, Class IIa or b, and Class III recommendations and have used the conventional language adopted by AHA/ACC/ESC Guidelines to express each class. All recommendations are level of evidence (LOE) C (i.e., based on experts' opinions). A Class I recommendation ( “is recommended” ) was applied for genetic testing in index cases with a sound clinical suspicion for the presence of a channelopathy or a cardiomyopathy when the positive predictive value of a genetic test is high (likelihood of positive result >40% and signal/noise ratio >10; Table 3), AND/OR when …

Screening ethnically diverse human embryonic stem cells identifies a chromosome 20 minimal amplicon conferring growth advantage

Abstract: The International Stem Cell Initiative analyzed 125 human embryonic stem (ES) cell lines and 11 induced pluripotent stem (iPS) cell lines, from 38 laboratories worldwide, for genetic changes occurring during culture. Most lines were analyzed at an early and late passage. Single-nucleotide polymorphism (SNP) analysis revealed that they included representatives of most major ethnic groups. Most lines remained karyotypically normal, but there was a progressive tendency to acquire changes on prolonged culture, commonly affecting chromosomes 1, 12, 17 and 20. DNA methylation patterns changed haphazardly with no link to time in culture. Structural variants, determined from the SNP arrays, also appeared sporadically. No common variants related to culture were observed on chromosomes 1, 12 and 17, but a minimal amplicon in chromosome 20q11.21, including three genes expressed in human ES cells, ID1, BCL2L1 and HM13, occurred in >20% of the lines. Of these genes, BCL2L1 is a strong candidate for driving culture adaptation of ES cells.

Epidemiology and management of painful procedures in children in Canadian hospitals

Abstract: Background Children being cared for in hospital undergo multiple painful procedures daily. However, little is known about the frequency of these procedures and associated interventions to manage the pain. We undertook this study to determine, for children in Canadian hospitals, the frequency of painful procedures, the types of pain management interventions associated with painful procedures and the influence of the type of hospital unit on procedural pain management. Methods We reviewed medical charts for infants and children up to 18 years of age who had been admitted to 32 inpatient units at eight Canadian pediatric hospitals between October 2007 and April 2008. We recorded all of the painful procedures performed and the pain management interventions that had been implemented in the 24-hour period preceding data collection. We performed descriptive and comparative (analysis of variance, χ2) analyses. Results Of the 3822 children included in the study, 2987 (78.2%) had undergone at least one painful procedure in the 24-hour period preceding data collection, for a total of 18 929 painful procedures (mean 6.3 per child who had any painful procedure). For 2334 (78.1%) of the 2987 children who had a painful procedure, a pain management intervention in the previous 24 hours was documented in the chart: 1980 (84.8%) had a pharmacologic intervention, 609 (26.1%) a physical intervention, 584 (25.0%) a psychologic intervention and 753 (32.3%) a combination of interventions. However, for only 844 (28.3%) of the 2987 children was one or more pain management interventions administered and documented specifically for a painful procedure. Pediatric intensive care units reported the highest proportion of painful procedures and analgesics administered. Interpretation For less than one-third of painful procedures was there documentation of one or more specific pain management interventions. Strategies for implementing changes in pain management must be tailored to the type of hospital unit.

Molecular diagnosis of respiratory virus infections

Abstract: The appearance of eight new respiratory viruses, including the SARS coronavirus in 2003 and swine-origin influenza A/H1N1 in 2009, in the human population in the past nine years has tested the ability of virology laboratories to develop diagnostic tests to identify these viruses. Nucleic acid based amplification tests (NATs) for respiratory viruses were first introduced two decades ago and today are utilized for the detection of both conventional and emerging viruses. These tests are more sensitive than other diagnostic approaches, including virus isolation in cell culture, shell vial culture (SVC), antigen detection by direct fluorescent antibody (DFA) staining, and rapid enzyme immunoassay (EIA), and now form the backbone of clinical virology laboratory testing around the world. NATs not only provide fast, accurate and sensitive detection of respiratory viruses in clinical specimens but also have increased our understanding of the epidemiology of both new emerging viruses such as the pandemic H1N1 influenza virus of 2009, and conventional viruses such as the common cold viruses, including rhinovirus and coronavirus. Multiplex polymerase chain reaction (PCR) assays introduced in the last five years detect up to 19 different viruses in a single test. Several multiplex PCR tests are now commercially available and tests are working their way into clinical laboratories. The final chapter in the evolution of respiratory virus diagnostics has been the addition of allelic discrimination and detection of single nucleotide polymorphisms associated with antiviral resistance. These assays are now being multiplexed with primary detection and subtyping assays, especially in the case of influenza virus. These resistance assays, together with viral load assays, will enable clinical laboratories to provide physicians with new and important information for optimal treatment of respiratory virus infections.

Pediatric and adult sonic hedgehog medulloblastomas are clinically and molecularly distinct

Abstract: Recent integrative genomic approaches have defined molecular subgroups of medulloblastoma that are genetically and clinically distinct. Sonic hedgehog (Shh) medulloblastomas account for one-third of all cases and comprise the majority of infant and adult medulloblastomas. To discern molecular heterogeneity among Shh-medulloblastomas, we analyzed transcriptional profiles from four independent Shh-medulloblastoma expression datasets (n = 66). Unsupervised clustering analyses demonstrated a clear distinction between infant and adult Shh-medulloblastomas, which was reliably replicated across datasets. Comparison of transcriptomes from infant and adult Shh-medulloblastomas revealed deregulation of multiple gene families, including genes implicated in cellular development, synaptogenesis, and extracellular matrix maintenance. Furthermore, metastatic dissemination is a marker of poor prognosis in adult, but not in pediatric Shh-medulloblastomas. Children with desmoplastic Shh-medulloblastomas have a better prognosis than those with Shh-medulloblastomas and classic histology. Desmoplasia is not prognostic for adult Shh-medulloblastoma. Cytogenetic analysis of a large, non-overlapping cohort of Shh-medulloblastomas (n = 151) revealed significant over-representation of chromosome 10q deletion (P < 0.001) and MYCN amplification (P < 0.05) in pediatric Shh cases compared with adults. Adult Shh-medulloblastomas harboring chromosome 10q deletion, 2 gain, 17p deletion, 17q gain, and/or GLI2 amplification have a much worse prognosis as compared to pediatric cases exhibiting the same aberrations. Collectively, our data demonstrate that pediatric and adult Shh-medulloblastomas are clinically, transcriptionally, genetically, and prognostically distinct.

The ubiquitin-binding adaptor proteins p62/SQSTM1 and NDP52 are recruited independently to bacteria-associated microdomains to target Salmonella to the autophagy pathway

Abstract: Autophagy is an innate immune defense against bacterial invasion. Recent studies show that two adaptor proteins, p62 and NDP52, are required for autophagy of the bacterial pathogen Salmonella enterica serovar Typhimurium (S. typhimurium). However, it is not known why two different adaptors are required to target the same bacterial cargo to autophagy. Here we show that both adaptors are recruited to bacteria with similar kinetics, that they are recruited to bacteria independently of each other, and that depletion of either adaptor leads to impairment of antibacterial autophagy. Depletion of both adaptors does not synergistically impair autophagy, indicating they act in the same pathway. Remarkably, we observed that these adaptors do not colocalize, but rather form non-overlapping microdomains surrounding bacteria. We conclude that p62 and NDP52 act cooperatively to drive efficient antibacterial autophagy by targeting the protein complexes they coordinate to distinct micro-domains associated with bacteria.

Challenges in health state valuation in paediatric economic evaluation: are QALYs contraindicated?

Abstract: With the growth in the use of health economic evaluation to inform healthcare resource allocation decisions, the challenges in applying standard methods to child health have become apparent. A unique limitation is the paucity of child-specific preference-based measures. A single, valid, preference-based measure of utility that can be used in children of all ages does not exist. Thus, the ability to derive a QALY for use in cost-utility analysis (CUA) is compromised. This paper presents and discusses existing and novel options for deriving utilities for paediatric health states for use in CUAs. While a direct elicitation may be preferred, a child's ability to complete a standard gamble or time trade-off task is hampered by cognitive and age limitations. The abstract notions contained in indirect instruments such as the EQ-5D and Health Utilities Index may also pose challenges for young children. Novel approaches to overcome these challenges include the development of age-appropriate instruments such as the EQ-5D-Y, the development of new child-specific utility instruments such as the Child Health Utility-9D and the re-calibration of existing adult instruments to derive preference weights for health states from children themselves. For children aged <6 years, researchers have little choice but to use a proxy reporter such as parents. While parents may be reliable reporters for physical activity limitations and externally manifest symptoms, their ability to accurately report on subjective outcomes such as emotion is questionable. Catalogues of utility weights for a range of conditions are increasingly becoming available but retain many of the same limitations as valuing health states from children or from proxies. Given the dynamic relationship in quality of life (QOL) between family members when a child is ill, it seems appropriate to consider a 'family perspective' rather than an individual perspective in child health state valuation. In a collective approach, health state utilities derived from multiple family members may be combined mathematically. Alternatively, in a unitary approach, a single utility estimate may be determined to represent the family's perspective. This may include deriving utilities through parent-child dyad estimation or by using a household model that combines the utility weights of the patient and family members, incorporating reciprocal QOL effects. While these various approaches to child health state valuation represent novel research developments, the measurement challenges and threats to validity persist. Given the importance of non-health benefits to child health, especially in the domains of education and public policy, it may be worthwhile to consider an approach that allows incorporation of externalities to produce a cost-benefit analysis. The use of discrete-choice methods to assess willingness to pay for novel child health interventions holds promise as a means to produce meaningful economic evidence. Regardless of the approach taken, the highest degree of methodological rigour is essential. The increasing attention being paid by health economic researchers to the measurement challenges of paediatric health state valuation can only increase the value of child health economic evidence for decision making.

aHUS caused by complement dysregulation: new therapies on the horizon.

Abstract: Atypical hemolytic uremic syndrome (aHUS) is a heterogeneous disease that is caused by defective complement regulation in over 50% of cases. Mutations have been identified in genes encoding both complement regulators [complement factor H (CFH), complement factor I (CFI), complement factor H-related proteins (CFHR), and membrane cofactor protein (MCP)], as well as complement activators [complement factor B (CFB) and C3]. More recently, mutations have also been identified in thrombomodulin (THBD), an anticoagulant glycoprotein that plays a role in the inactivation of C3a and C5a. Inhibitory autoantibodies to CFH account for an additional 5–10% of cases and can occur in isolation or in association with mutations in CFH, CFI, CFHR 1, 3, 4, and MCP. Plasma therapies are considered the mainstay of therapy in aHUS secondary to defective complement regulation and may be administered as plasma infusions or plasma exchange. However, in certain cases, despite initiation of plasma therapy, renal function continues to deteriorate with progression to end-stage renal disease and renal transplantation. Recently, eculizumab, a humanized monoclonal antibody against C5, has been described as an effective therapeutic strategy in the management of refractory aHUS that has failed to respond to plasma therapy. Clinical trials are now underway to further evaluate the efficacy of eculizumab in the management of both plasma-sensitive and plasma-resistant aHUS.

Identifying determinants of quality of life of children with cancer and childhood cancer survivors: a systematic review

Abstract: Purpose This paper describes a systematic review conducted to identify factors that have been investigated as explanations of variability in the quality of life of children with cancer and childhood cancer survivors. Our purpose was to build an evidence base that could be used to guide and direct future research. Methods MEDLINE, CINAHL, EMBASE, PsycINFO, Cancerlit, and Sociological Abstracts were searched from the inception of each database to June 15, 2009 using the following search terms: “quality of life, ”“ health-related quality of life, ”“ quality adjusted life years, ”“ health status, ”“ functional status, ”“ well-being,” or “patientreported outcome.” Sample characteristics and information about the relationship between a quality of life domain or total scale score and at least one factor (e.g., child gender or age, coping skills, family income) were extracted from eligible studies. Results Nine cancer-specific and nine generic QOL questionnaires were used in 58 publications described 239 factors (50 unique factors). The large number of cancer, treatment, child, and family variables considered indicates that extensive research activity has occurred. However, most of the variables identified were examined in only a few studies and most represent medical and treatment variables with less research attention paid to child and family variables. Conclusions Our study has compiled evidence about determinants of QOL for children with cancer and childhood cancer survivors from the existing literature. Future research can build on this evidence base to expand the range of factors studied as most research to date has focused on medical and treatment factors.

Predicting Parenting Stress in Families of Children with ADHD: Parent and Contextual Factors

Abstract: We examined parental ADHD symptoms and contextual (parental education, social support, marital status) predictors of parent domain parenting stress (parental distress) as a function of child ADHD symptoms in a sample of 95 parents of 8 to 12 year-old children with and without ADHD. Parents’ perceptions of parental distress and social support were inversely-related. Parental ADHD symptomatology was the strongest predictor of parental distress of the variables considered. Models using teacher reports of child ADHD symptomatology and oppositionality differed from ones using parent reports, in that child oppositionality was only predictive of parental distress in the parent-report model. A post-hoc analysis showed that child factors did not predict parental distress over and above parent ADHD symptoms and contextual factors. These results suggest that parental ADHD symptomatology and parenting stress reduction should be considered in development of interventions for families of children with ADHD.

Anticoagulation for cerebral venous sinus thrombosis.

Abstract: Background Treatment of cerebral venous sinus thrombosis with anticoagulants has been controversial. Anticoagulants may prevent new venous infarcts, neurologic deterioration and pulmonary embolism but may also promote haemorrhages. Objectives To assess the effectiveness and safety of anticoagulant therapy in patients with confirmed cerebral venous sinus thrombosis. Search methods We searched the Cochrane Stroke Group Trials Register (last searched August 2010), MEDLINE (1950 to August 2010), EMBASE (1980 to August 2010) and the Cochrane Central Register of Controlled Trials (The Cochrane Library, 2011 Issue 1). In an effort to identify further published, unpublished and ongoing trials we searched ongoing trials registers and reference lists of relevant articles, and contacted authors. Selection criteria Unconfounded randomised controlled trials in which anticoagulant therapy was compared with placebo or open control in patients with cerebral venous sinus thrombosis (confirmed by intra-arterial contrast, or venography with magnetic resonance, or venography with computed tomography imaging). Data collection and analysis Two review authors independently extracted outcomes for each of the two treatment groups (anticoagulant treatment and control). The outcome data for each patient were analysed in the treatment group to which the patient was originally allocated (intention-to-treat analysis). We calculated a weighted estimate of the treatment effects across trials (relative risk, absolute risk reduction). Main results We included two small trials involving 79 patients. One trial (20 patients) examined the efficacy of intravenous, adjusted dose unfractionated heparin. The other trial (59 patients) examined high dose, body weight adjusted, subcutaneous, low-molecular weight heparin (nadroparin). Anticoagulant therapy was associated with a pooled relative risk of death of 0.33 (95% confidence interval (CI) 0.08 to 1.21) and of death or dependency of 0.46 (95% CI 0.16 to 1.31). The absolute reduction in the risk of death or dependency was 13% (95% CI 30% to -3%). No new symptomatic intracerebral haemorrhages were observed. One major gastro-intestinal haemorrhage occurred after anticoagulant treatment. Two control patients (placebo) had a diagnosis of probable pulmonary embolism (one fatal). Authors' conclusions Based upon the limited evidence available, anticoagulant treatment for cerebral venous sinus thrombosis appeared to be safe and was associated with a potentially important reduction in the risk of death or dependency which did not reach statistical significance.

Mouse snail is a target gene for HIF.

Abstract: The transcriptional inhibitor Snail is a critical regulator for epithelial-mesenchymal transition (EMT). Although low oxygen induces Snail transcription, thereby stimulating EMT, a direct role of hypoxia-inducible factor (HIF) in this process remains to be demonstrated. Here we show that hypoxia induces the expression of Snail via HIF. In silico analysis identified a potential hypoxia-response element (HRE) close to the minimal promoter of the human and mouse genome of the snail gene. Gel shift assays demonstrated that a specific hypoxia-inducible complex is formed with the putative HRE and that the complex contains HIF proteins. ChIP assays confirmed the interaction of HIF proteins with the putative HRE in vivo. Reporter gene analyses showed that the putative HRE responds to hypoxia in its natural position as well as in front of a heterologous promoter and that the HRE is directly activated by HIF-1α or HIF-2α. HIF knockdown with siRNA at 2% oxygen and overexpression of an oxygen-insensitive HIF (HIF-ΔODD) mutant at 21% oxygen showed that HIF regulates Snail activation and subsequent cell migration. Our findings identify snail as a HIF target gene and provide novel insights into the regulation of snail and hypoxia-induced EMT.

Safety and efficacy of maintenance infliximab therapy for moderate-to-severe Crohn's disease in children: REACH open-label extension.

Abstract: Objective:Assess long-term effects of maintenance infliximab therapy in children with moderately-to-severely active Crohn’s disease.Research design and methods:One hundred twelve patients with a Pediatric Crohn’s Disease Activity Index (PCDAI) score >30 received infliximab 5 mg/kg at weeks 0, 2, and 6 in the REACH study. Patients considered responders at week 10 were randomized to infliximab 5 mg/kg every 8 (q8w) or 12 (q12w) weeks. Patients who completed treatment through week 46, and who the investigator believed would benefit from continued treatment, could enter the open-label extension (OLE) and receive up to three additional years of infliximab. No hypothesis testing was performed.Clinical trial registration:www.clinicaltrials.gov, identifier: NCT0020767.Results:Sixty children entered the OLE: 33, 12, and 15 patients were receiving infliximab 5 mg/kg q8w, 5 mg/kg q12w, and 10 mg/kg q8w, respectively, at extension entry. Patients receiving infliximab for up to 3 years during the OLE maintaine...

Teachers’ Reported Use of Instructional and Behavior Management Practices for Students with Behavior Problems: Relationship to Role and Level of Training in ADHD

Abstract: The present study examined general and special education teachers’ self-reported level of in-service training in attention-deficit hyperactivity disorder (ADHD), a common childhood mental health disorder, and the relationship between teachers’ level of training in ADHD and their reported use of a range of recommended instructional and behavior management approaches for students exhibiting behavior problems. The analyses revealed that the majority of general education teachers (76%), and almost half (41%) of the special education teachers, reported having no or brief in-service training in ADHD. General education teachers with moderate to extensive in-service training in ADHD reported significantly greater use of the recommended approaches (as indicated by their scores on the Instructional and Behavior Management Survey) than general educators with little or no training in ADHD. Implications for research and practice are discussed.

Asymmetric Dimethylarginine Is Increased in Asthma

Abstract: Rationale: Asymmetric dimethylarginine (ADMA) is an endogenous nitric oxide synthase (NOS) inhibitor that competes with l-arginine for binding to NOS. It has been suggested that ADMA contributes to inflammation, collagen deposition, nitrosative stress, and lung function in murine models.Objectives: To test the hypothesis that ADMA is increased in asthma and that NOS inhibition by ADMA contributes to airways obstruction.Methods: We assessed alterations of l-arginine, ADMA, and symmetric dimethylarginine (SDMA) levels in a murine model of allergic airways inflammation using LC-tandem mass spectrometry. Based on the levels of ADMA observed in the murine model, we further tested the direct effects of nebulized inhaled ADMA on airways responsiveness in naive control mice. We also assessed alterations of l-arginine, ADMA, and SDMA in humans in adult lung specimens and sputum samples from pediatric patients with asthma.Measurements and Main Results: ADMA was increased in lungs from the murine model of allergic a...

Renal dysfunction in patients with thalassaemia.

Abstract: Little is known about the effects of thalassaemia on the kidney. Characterization of underlying renal function abnormalities in thalassaemia is timely because the newer iron chelator, deferasirox, can be nephrotoxic. We aimed to determine the prevalence and correlates of renal abnormalities in thalassaemia patients, treated before deferasirox was widely available, using 24-h collections of urine. We calculated creatinine clearance and urine calcium-to-creatinine ratio and measured urinary β(2) -microglobulin, albumin, and protein. We used multivariate modelling to identify clinical, therapeutic, and laboratory predictors of renal dysfunction. One-third of thalassaemia patients who were not regularly transfused had abnormally high creatinine clearance. Regular transfusions were associated with a decrease in clearance (P = 0·004). Almost one-third of patients with thalassaemia had hypercalciuria, and regular transfusions were associated with an increase in the frequency and degree of hypercalciuria (P < 0·0001). Albuminuria was found in over half of patients, but was not consistently associated with transfusion therapy. In summary, renal hyperfiltration, hypercalciuria, and albuminuria are common in thalassaemia. Higher transfusion intensity is associated with lower creatinine clearance but more frequent hypercalciuria. The transfusion effect needs to be better understood. Awareness of underlying renal dysfunction in thalassaemia can inform decisions now about the use and monitoring of iron chelation.

Mutation analysis in Bardet-Biedl syndrome by DNA pooling and massively parallel resequencing in 105 individuals

Abstract: Bardet–Biedl syndrome (BBS) is a rare, primarily autosomal-recessive ciliopathy. The phenotype of this pleiotropic disease includes retinitis pigmentosa, postaxial polydactyly, truncal obesity, learning disabilities, hypogonadism and renal anomalies, among others. To date, mutations in 15 genes (BBS1–BBS14, SDCCAG8) have been described to cause BBS. The broad genetic locus heterogeneity renders mutation screening time-consuming and expensive. We applied a strategy of DNA pooling and subsequent massively parallel resequencing (MPR) to screen individuals affected with BBS from 105 families for mutations in 12 known BBS genes. DNA was pooled in 5 pools of 21 individuals each. All 132 coding exons of BBS1–BBS12 were amplified by conventional PCR. Subsequent MPR was performed on an Illumina Genome Analyzer II™ platform. Following mutation identification, the mutation carrier was assigned by CEL I endonuclease heteroduplex screening and confirmed by Sanger sequencing. In 29 out of 105 individuals (28%), both mutated alleles were identified in 10 different BBS genes. A total of 35 different disease-causing mutations were confirmed, of which 18 mutations were novel. In 12 additional families, a total of 12 different single heterozygous changes of uncertain pathogenicity were found. Thus, DNA pooling combined with MPR offers a valuable strategy for mutation analysis of large patient cohorts, especially in genetically heterogeneous diseases such as BBS.

Patient gender affects the referral and recommendation for total joint arthroplasty.

Abstract: Background Rates of use of total joint arthroplasty among appropriate and willing candidates are lower in women than in men. A number of factors may explain this gender disparity, including patients’ preferences for surgery, gender bias influencing physicians’ clinical decision-making, and the patient-physician interaction.

Motivational Interviewing as an intervention to increase adolescent self-efficacy and promote weight loss: Methodology and design

Abstract: Childhood obesity is associated with serious physiological and psychological consequences including type 2 diabetes, higher rates of depression and low self-esteem. With the population of overweight and obese youth increasing, appropriate interventions are needed that speak to the issue of readiness to change and motivation to maintain adherence to healthy behavior changes. Motivational Interviewing (MI) is a method of therapy found to resolve ambivalence, enhance intrinsic motivation and promote confidence in a person's ability to make behavior changes. While MI has shown promise in the adult obesity literature as effecting positive lifestyle change, little is known about the effectiveness of MI with overweight and obese youth. This study aims to: 1) demonstrate that MI is an effective intervention for increasing a person's self-efficacy; 2) demonstrate that exposure to MI will facilitate healthy behavior changes; 3) explore psychological changes related to participation in MI and 4) compare physiological and anthropometric outcomes before and after intervention. The current investigation is a prospective study conducted with ongoing participants who regularly attend an outpatient pediatric care center for weight-loss. Overweight youth (BMI > 85th %ile) between the ages of 10 and 18 who meet eligibility criteria will be recruited. Participants will be randomly assigned to a control group (social skills training) or a treatment group (MI). Participants will meet with the therapist for approximately 30 minutes prior to seeing the dietician, over the course of 6 months. Participants will also undergo a full day assessment at the beginning and end of psychology intervention to evaluate body fat, and metabolic risk (screening for diabetes, high cholesterol, high blood pressure and fitness level). The paper and pencil portions of the assessments as well as the clinical testing will occur at baseline and at the conclusion of the intervention (6 months) with a repeat assessment 6 months following the completion of the intervention. Results from this study are expected to enhance our understanding of the efficacy of MI with children and adolescents who are overweight or obese. Current Controlled Trials # NCT00326404 .

Correlation Between Local Hemodynamics and Lesion Distribution in a Novel Aortic Regurgitation Murine Model of Atherosclerosis

Abstract: Following surgical induction of aortic valve regurgitation (AR), extensive atherosclerotic plaque development along the descending thoracic and abdominal aorta of Ldlr⁻/⁻ mice has been reported, with distinct spatial distributions suggestive of a strong local hemodynamic influence. The objective of this study was to test, using image-based computational fluid dynamics (CFD), whether this is indeed the case. The lumen geometry was reconstructed from micro-CT scanning of a control Ldlr⁻/⁻ mouse, and CFD simulations were carried out for both AR and control flow conditions derived from Doppler ultrasound measurements and literature data. Maps of time-averaged wall shear stress magnitude (TAWSS), oscillatory shear index (OSI) and relative residence time (RRT) were compared against the spatial distributions of plaque stained with oil red O, previously acquired in a group of AR and control mice. Maps of OSI and RRT were found to be consistent with plaque distributions in the AR mice and the absence of plaque in the control mice. TAWSS was uniformly lower under control vs. AR flow conditions, suggesting that levels (> 100 dyn/cm²) exceeded those required to alone induce a pro-atherogenic response. Simulations of a straightened CFD model confirmed the importance of anatomical curvature for explaining the spatial distribution of lesions in the AR mice. In summary, oscillatory and retrograde flow induced in the AR mice, without concomitant low shear, may exacerbate or accelerate lesion formation, but the distinct anatomical curvature of the mouse aorta is responsible for the spatial distribution of lesions.

Use it or lose it? Lessons learned from the developing brains of children who are deaf and use cochlear implants to hear.

Abstract: In the present paper, we review what is currently known about the effects of deafness on the developing human auditory system and ask: Without use, does the immature auditory system lose the ability to normally function and mature? Any change to the structure or function of the auditory pathways resulting from a lack of activity will have important implications for future use through an auditory prosthesis such as a cochlear implant. Data to date show that deafness in children arrests and disrupts normal auditory development. Multiple changes to the auditory pathways occur during the period of deafness with the extent and type of change being dependent upon the age and stage of auditory development at onset of deafness, the cause or type of deafness, and the length of time the immature auditory pathways are left without significant input. Structural changes to the auditory nerve, brainstem, and cortex have been described in animal models of deafness as well in humans who are deaf. Functional changes in deaf auditory pathways have been evaluated by using a cochlear implant to stimulate the auditory nerve with electrical pulses. Studies of electrically evoked activity in the immature deaf auditory system have demonstrated that auditory brainstem development is arrested and that thalamo-cortical areas are vulnerable to being taken over by other competitive inputs (cross-modal plasticity). Indeed, enhanced peripheral sight and detection of visual movement in congenitally deaf cats and adults have been linked to activity in specific areas of what would normally be auditory cortex. Cochlear implants can stimulate developmental plasticity in the auditory brainstem even after many years of deafness in childhood but changes in the auditory cortex are limited, at least in part, by the degree of reorganization which occurred during the period of deafness. Consequently, we must identify hearing loss rapidly (i.e., at birth for congenital deficits) and provide cochlear implants to appropriate candidates as soon as possible. Doing so has facilitated auditory development in the thalamo-cortex and allowed children who are deaf to perceive and use spoken language.

Neurexins and Neuroligins: Recent Insights from Invertebrates

Abstract: During brain development, each neuron must find and synapse with the correct pre- and postsynaptic partners. The complexity of these connections and the relatively large distances some neurons must send their axons to find the correct partners makes studying brain development one of the most challenging, and yet fascinating disciplines in biology. Furthermore, once the initial connections have been made, the neurons constantly remodel their dendritic and axonal arbours in response to changing demands. Neurexin and neuroligin are two cell adhesion molecules identified as important regulators of this process. The importance of these genes in the development and modulation of synaptic connectivity is emphasised by the observation that mutations in these genes in humans have been associated with cognitive disorders such as Autism spectrum disorders, Tourette syndrome and Schizophrenia. The present review will discuss recent advances in our understanding of the role of these genes in synaptic development and modulation, and in particular, we will focus on recent work in invertebrate models, and how these results relate to studies in mammals.

GLI3 repressor controls functional development of the mouse ureter

Abstract: Obstructive and nonobstructive forms of hydronephrosis (increased diameter of the renal pelvis and calyces) and hydroureter (dilatation of the ureter) are the most frequently detected antenatal abnormalities, yet the underlying molecular mechanisms are largely undefined. Hedgehog (Hh) proteins control tissue patterning and cell differentiation by promoting GLI-dependent transcriptional activation and by inhibiting the processing of GLI3 to a transcriptional repressor. Genetic mutations that generate a truncated GLI3 protein similar in size to the repressor in humans with Pallister-Hall syndrome (PHS; a disorder whose characteristics include renal abnormalities) and hydroureter implicate Hh-dependent signaling in ureter morphogenesis and function. Here, we determined that Hh signaling controls 2 cell populations required for the initiation and transmission of coordinated ureter contractions. Tissue-specific inactivation of the Hh cell surface effector Smoothened (Smo) in the renal pelvic and upper ureteric mesenchyme resulted in nonobstructive hydronephrosis and hydroureter characterized by ureter dyskinesia. Mutant mice had reduced expression of markers of cell populations implicated in the coordination of unidirectional ureter peristalsis (specifically, Kit and hyperpolarization-activation cation–3 channel [Hcn3]), but exhibited normal epithelial and smooth muscle cell differentiation. Kit deficiency in a mouse model of PHS suggested a pathogenic role for GLI3 repressor in Smo-deficient embryos; indeed, genetic inactivation of Gli3 in Smo-deficient mice rescued their hydronephrosis, hydroureter, Kit and Hcn3 expression, and ureter peristalsis. Together, these data demonstrate that Hh signaling controls Kit and Hcn3 expression and ureter peristalsis.

Whole-body MR imaging in children: principles, technique, current applications, and future directions.

Abstract: In whole-body magnetic resonance (MR) imaging, the entire body from the vertex to the toes is imaged in one or more planes with one or multiple sequences to allow evaluation of multisystem diseases in a single examination. Whole-body MR imaging is particularly useful for examining children because it does not involve exposure to radiation and allows a complete work-up for disease staging within a single session of sedation or anesthesia. At whole-body MR imaging with a sliding table platform, a body coil may be used, but the resultant images have a low signal-to-noise ratio (SNR) and low resolution; use of a combination of phased-array coils results in images with an improved SNR and higher resolution. As whole-body MR imaging techniques undergo further refinement, the role of the modality in oncologic and nononcologic imaging continues to expand. Its use in the staging of lymphoma and other malignancies has been studied extensively. Whole-body MR imaging does not provide functional information and cannot yet be used to differentiate benign from malignant lymphadenopathy. However, whole-body MR imaging performed with integrated diffusion-weighted sequences may complement or replace positron emission tomography, which involves substantial radiation exposure. Other promising avenues for future research include whole-body MR imaging at 3 T and the combination of molecular imaging or positron emission tomography with whole-body MR imaging.

Impact of hair-care products on FAEE hair concentrations in substance abuse monitoring

Abstract: Previous studies have indicated that the use of high-ethanol-content (>65%) hair-care products may elevate fatty acid ethyl ester (FAEE) concentrations in hair. In this case series, nine individuals were identified by FAEE analysis to be chronic alcohol abusers in the context of child-welfare substance abuse monitoring. Based on patient claims of moderate or no alcohol consumption, the presence of ethanol in the patients’ hair-care regimens was investigated. Samples were additionally tested for the presence of ethyl glucuronide (EtG). From a total of nine patients, 12 hair samples were submitted for analysis. Patient histories were obtained as well as Material Safety Data Sheets (MSDS) listing hair-care product ethanol content. Hair samples were pre-washed to remove external contamination and analyzed for FAEE and EtG by GC-MS. According to the Society of Hair Testing consensus guidelines, FAEE levels exceeding 0.50 ng/mg and/or EtG levels exceeding 30 pg/mg indicate chronic excessive alcohol consumption. Upon initial analysis, the nine samples exhibited positive FAEE findings ranging from 0.496 to 4.984 ng/mg. MSDS review revealed the presence of ethanol from 10% to 95% by volume in at least one hair-care product used by each individual. Results of the EtG analysis ranged from 1.9 to 23.5 pg/mg. These findings indicate that regular use of products with ethanol content as low as 10% can impact FAEE results. EtG analysis should be used to confirm FAEE findings and appears to be unaffected by hair-care products, likely due to alternative mechanisms of incorporation.