Sequential MRI reveals individual level deformities in the growing scoliotic spine that are clinically masked by the Cobb angle

Introduction Clinically, the Cobb angle method measures the overall scoliotic curve in the coronal plane but does not measure individual vertebra and disc wedging. The contributions of the vertebrae and discs in the growing scoliotic spine were measured to investigate coronal plane deformity progression with growth. Methods A 0.49mm isotropic 3D MRI technique was developed to investigate the level-by-level changes that occur in the growing spine of a group of Adolescent Idiopathic Scoliosis (AIS) patients, who received two to four sequential scans (spaced 3-12 months apart). The coronal plane wedge angles of each vertebra and disc in the major curve were measured to capture any changes that occurred during their adolescent growth phase. Results Seventeen patients had at least two scans. Mean patient age was 12.9 years (SD 1.5 years). Sixteen were classified as right-sided major thoracic Lenke Type 1 (one left sided). Mean standing Cobb angle at initial presentation was 31° (SD 12°). Six received two scans, nine three scans and two four scans, with 65% showing a Cobb angle progression of 5° or more between scans. Overall, there was no clear pattern of deformity progression of individual vertebrae and discs, nor between patients who progressed and those who didn’t. There were measurable changes in the wedging of the vertebrae and discs in all patients. In sequential scans, change in direction of wedging was also seen. In several patients there was reverse wedging in the discs that counteracted increased wedging of the vertebrae such that no change in overall Cobb angle was seen. Conclusion Sequential MRI data showed complex patterns of deformity progression. Changes to the wedging of individual vertebrae and discs may occur in patients who have no increase in Cobb angle measure; the Cobb method alone may be insufficient to capture the complex mechanisms of deformity progression.

Sequential MRI of growing scoliotic spines reveals individual level deformities that are clinically masked by the cobb angle

INTRODUCTION. Clinically, the Cobb angle method measures the overall scoliotic curve in the coronal plane but does not measure individual vertebra and disc wedging. The contributions of the vertebrae and discs in the growing scoliotic spine were measured to investigate coronal plane deformity progression with growth. METHODS. A 0.49mm isotropic 3D MRI technique was developed to investigate the level-by-level changes that occur in the growing spine of a group of Adolescent Idiopathic Scoliosis (AIS) patients, who received two to four sequential scans (spaced 3-12 months apart). The coronal plane wedge angles of each vertebra and disc in the major curve were measured to capture any changes that occurred during their adolescent growth phase. RESULTS. Seventeen patients had at least two scans. Mean patient age was 12.9 years (SD 1.5 years). Sixteen were classified as right-sided major thoracic Lenke Type 1 (one left sided). Mean standing Cobb angle at initial presentation was 31° (SD 12°). Six received two scans, nine three scans and two four scans, with 65% showing a Cobb angle progression of 5° or more between scans. Overall, there was no clear pattern of deformity progression of individual vertebrae and discs, nor between patients who progressed and those who didn’t. There were measurable changes in the wedging of the vertebrae and discs in all patients. In sequential scans, change in direction of wedging was also seen. In several patients there was reverse wedging in the discs that counteracted increased wedging of the vertebrae such that no change in overall Cobb angle was seen. CONCLUSION. Sequential MRI data showed complex patterns of deformity progression. Changes to the wedging of individual vertebrae and discs may occur in patients who have no increase in Cobb angle measure; the Cobb method alone may be insufficient to capture the complex mechanisms of deformity progression.

Sequential MRI reveals individual level deformities in the growing scoliotic spine that are not seen clinically by the cobb angle

Clinically, the Cobb angle method measures the overall scoliotic curve in the coronal plane but does not measure individual vertebra and disc wedging. The contributions of the vertebrae and discs in the growing scoliotic spine were measured to investigate coronal plane deformity progression with growth. Sequential MRI data in this project showed complex patterns of deformity progression. Changes to the wedging of individual vertebrae and discs may occur in patients who have no increase in Cobb angle measure; the Cobb method alone may be insufficient to capture the complex mechanisms of deformity progression.

Interleukin 10 polymorphisms in ankylosing spondylitis

Genetic polymorphisms of the IL10 promoter region have been implicated in many autoimmune diseases, including seronegative spondyloarthropathies. We studied three SNPs (IL10-1087,-824, and -597) and two microsafellites(IL10R and IL10G) lying within the promoter region of IL10 for association with susceptibility to and clinical manifestations of ankylosing spondylitis (AS), a common form of spondyloarthritis. Four hundred and sixty-eight individuals from 182 Finnish families affected with AS were studied. No association between individual IL10 promoter region polymorphisms or marker haplotype was observed with susceptibility to AS, but weak association was noted between the IL10-597 and -824 SNPs and age of disease onset (P= 0.01 for each SNP). The IL10.G4 allele was associated with BASFI (corrected for disease duration) (P= 0.03). We conclude that IL10 promoter polymorphisms have no significant effect on susceptibility to AS, but may play a minor role in determining age of disease onset and disease severity. © 2003 Nature Publishing Group All rights reserved.

Accounting for individual variability in the von Bertalanffy growth model

Estimation of von Bertalanffy growth parameters has received considerable attention in fisheries research. Since Sainsbury (1980, Can. J. Fish. Aquat. Sci. 37: 241-247) much of this research effort has centered on accounting for individual variability in the growth parameters. In this paper we demonstrate that, in analysis of tagging data, Sainsbury's method and its derivatives do not, in general, satisfactorily account for individual variability in growth, leading to inconsistent parameter estimates (the bias does not tend to zero as sample size increases to infinity). The bias arises because these methods do not use appropriate conditional expectations as a basis for estimation. This bias is found to be similar to that of the Fabens method. Such methods would be appropriate only under the assumption that the individual growth parameters that generate the growth increment were independent of the growth parameters that generated the initial length. However, such an assumption would be unrealistic. The results are derived analytically, and illustrated with a simulation study. Until techniques that take full account of the appropriate conditioning have been developed, the effect of individual variability on growth has yet to be fully understood.

Maximum likelihood estimation of mortality and growth with individual variability from multiple length-frequency data

We consider estimation of mortality rates and growth parameters from length-frequency data of a fish stock and derive the underlying length distribution of the population and the catch when there is individual variability in the von Bertalanffy growth parameter L-infinity. The model is flexible enough to accommodate 1) any recruitment pattern as a function of both time and length, 2) length-specific selectivity, and 3) varying fishing effort over time. The maximum likelihood method gives consistent estimates, provided the underlying distribution for individual variation in growth is correctly specified. Simulation results indicate that our method is reasonably robust to violations in the assumptions. The method is applied to tiger prawn data (Penaeus semisulcatus) to obtain estimates of natural and fishing mortality.

Effect of individual variability on estimation of population parameters from length-frequency data

We consider estimation of mortality rates and growth parameters from length-frequency data of a fish stock when there is individual variability in the von Bertalanffy growth parameter L-infinity and investigate the possible bias in the estimates when the individual variability is ignored. Three methods are examined: (i) the regression method based on the Beverton and Holt's (1956, Rapp. P.V. Reun. Cons. Int. Explor. Mer, 140: 67-83) equation; (ii) the moment method of Powell (1979, Rapp. PV. Reun. Int. Explor. Mer, 175: 167-169); and (iii) a generalization of Powell's method that estimates the individual variability to be incorporated into the estimation. It is found that the biases in the estimates from the existing methods are, in general, substantial, even when individual variability in growth is small and recruitment is uniform, and the generalized method performs better in terms of bias but is subject to a larger variation. There is a need to develop robust and flexible methods to deal with individual variability in the analysis of length-frequency data.

An improved Fabens method for estimation of growth parameters in the vonBertalanffy model with individual asymptotes

In the analysis of tagging data, it has been found that the least-squares method, based on the increment function known as the Fabens method, produces biased estimates because individual variability in growth is not allowed for. This paper modifies the Fabens method to account for individual variability in the length asymptote. Significance tests using t-statistics or log-likelihood ratio statistics may be applied to show the level of individual variability. Simulation results indicate that the modified method reduces the biases in the estimates to negligible proportions. Tagging data from tiger prawns (Penaeus esculentus and Penaeus semisulcatus) and rock lobster (Panulirus ornatus) are analysed as an illustration.

Radical nursing and the emergence of technique as healthcare technology

The integration of technology in care is core business in nursing and this role requires that we must understand and use technology informed by evidence that goes much deeper and broader than actions and behaviours. We need to delve more deeply into its complexity because there is nothing minor or insignificant about technology as a major influence in healthcare outcomes and experiences. Evidence is needed that addresses technology and nursing from perspectives that examine the effects of technology, especially related to increasing demands for efficiency, the relationship of technology to nursing and caring, and a range of philosophical questions associated with empowering people in their healthcare choices. Specifically, there is a need to confront in practice the ways technique influences care. Technique is the creation of a kind of thinking that is necessary for contemporary healthcare technology to develop and be applied in an efficient and rational manner. Technique is not an entity or specific thing, but rather a way of thinking that seeks to shape and organize nursing activity, and manage efficiently individual difference(s) in care. It emphasizes predetermined causal relationships, conformity, and sameness of product, process, and thought. In response is needed a radical vision of nursing that attempts in a real sense to ensure we meet the needs of individuals and their community. Activism and advocacy are needed, and a willingness to create a certain detachment from the imperatives that technique demands. It is argued that our responsibility as nurses is to respond in practice to the errors, advantages, difficulties, and temptations of technology for the benefit of those who most need our assistance and care.

Aging-in-place: Perspectives from the construction industry

Older adults report a desire to remain within the preferred environment for as long as possible. This desire is referred to as aging-in-place. Aging-in-place integrates housing and care options. Factors affecting the ability to remain within the preferred environment include current home designs, access to housing choices, social support networks, and community services, to name a few. Research supports physical and psychosocial benefits of aging-in-place for the individual. Home modifications have the potential to influence the quality of life in a number of positive directions that range from personal mobility to community engagement. Modifications range from minor to significant. Financial resources, contractor interest and expertise, consumer awareness and consumer opportunity affect the degree of change. Increasingly, construction professionals express an interest in learning more about aging-in place. Queries ranged from obtaining a greater understanding of the meaning of the concept, impact of demographic change on housing stock, and increased awareness of universal design features. This paper presents findings from a survey administered to current members of the Canadian Home Builders’ Association – Calgary Regional Office. Within this presentation, we report findings on members understanding of demographic change and the effect of this change on the current and future housing stock. We discuss perceived barriers and benefits of the development of business models to support aging-in-place. Finally, we conclude with discussion of educational support to enhance the understanding of aging-in-place.

Muscle morphometry of the individual hamstring muscles in semi-elite AFL Players: Preliminary findings from a longitudinal study

Hamstring strains in the Australian Football League (AFL) have a high incidence (15%) and recurrence rate (34%) with lateral hamstring injuries most common (83%). Retrospective studies have found significant muscle volume asymmetries ≤23 months post hamstring injury; however examination of the association between hamstring strains and muscle asymmetry has not been investigated prospectively. This study presents baseline data from a longitudinal study focusing on individual hamstring morphometry in uninjured and injured semi-elite AFL players.

Perceptions on the causes of individual and fraudulent co-offending: Views of forensic accountants

Individual and/or co-offenders fraudulent activities can have a devastating effect on a company’s reputation and credibility. Enron, Xerox, WorldCom, HIH Insurance and One.Tel are examples where stakeholders incurred substantial financial losses as a result of fraud and led to a loss of confidence in corporate dealings by the public in general. There are numerous theoretical approaches that attempt to explain how and why fraudulent acts occur, drawing on the fields of sociology, organisational, management and economic literature, but there is limited empirical evidence published in accounting literature. This qualitative inductive study analyses perceptions and experiences of forensic accountants to gain insights into individual fraud and co-offending in order to determine whether the conceptual framework developed from literature accurately depicts the causes of fraud committed by individuals and groups in the twenty-first century. Findings from the study both support and extend the conceptual framework, demonstrating that strain and anomie can result in fraud, that deviant sub-groups recruit and coerce members by providing relief from strain, and that inadequate corporate governance mechanisms both contribute to fraud occurring, and provide the opportunity for fraudulent activities to be executed and often remain undetected. Additional factors emerging from this study (the ‘technoconomy’, addiction and IT measures) were also identified as contributors to fraud, particularly relevant to the twenty-first century, and consequently, a refined conceptual framework is presented in the discussion and conclusion to the paper.

The dynamics of individual teacher autonomy: A case study of teachers' work in a Queensland secondary school

The emphasis on collegiality and collaboration in the literature on teachers' work and school reform has tended to underplay the significance of teacher autonomy. This thesis explores the dynamics of teachers' understandings and experiences of individual teacher autonomy (as contrasted with collective autonomy) in an independent school in Queensland which promoted itself as a 'teachers' school' with a strong commitment to individual teacher autonomy. The research was a case study which drew on methodological signposts from critical, feminist and traditional ethnography. Intensive fieldwork in the school over five months incorporated the ethnographic techniques of observation, interviews and document analysis. Teachers at Thornton College understood their experience of individual autonomy at three interrelated levels--in terms of their work in the classroom, their working life in the school, and their voice in the decision-making processes of the school. They felt that they experienced a great deal of individual autonomy at each of these three levels. These understandings and experiences of autonomy were encumbered or enabled by a range of internal and external stakeholder groups. There were also a number of structural influences (community perceptions, market forces, school size, time and bureaucracy) emerging from the economic, social and political structures in Australian society which influenced the experience of autonomy by teachers. The experience of individual teacher autonomy was constantly shifting, but there were some emergent patterns. Consensus on educational goals and vision, and strong expressions of trust and respect between teachers and stakeholders in the school, characterised the contexts in which teachers felt they experienced high levels of autonomy in their work. The demand for accountability and desire for relatedness motivated stakeholders and structural forces to influence teacher autonomy. Some significant gaps emerged between the rhetoric of a commitment to individual teacher autonomy and decision-making practices in the school, that gave ultimate power to the co-principals. Despite the rhetoric and promotion of non-hierarchical structures and collaborative decision-making processes, many teachers perceived that their experience of individual autonomy remained subject to the exercise of 'partial democracy' by school leaders.

Estimation and partitioning of polygenic variation captured by common SNPs for Alzheimer's disease, multiple sclerosis and endometriosis

Common diseases such as endometriosis (ED), Alzheimer's disease (AD) and multiple sclerosis (MS) account for a significant proportion of the health care burden in many countries. Genome-wide association studies (GWASs) for these diseases have identified a number of individual genetic variants contributing to the risk of those diseases. However, the effect size for most variants is small and collectively the known variants explain only a small proportion of the estimated heritability. We used a linear mixed model to fit all single nucleotide polymorphisms (SNPs) simultaneously, and estimated genetic variances on the liability scale using SNPs from GWASs in unrelated individuals for these three diseases. For each of the three diseases, case and control samples were not all genotyped in the same laboratory. We demonstrate that a careful analysis can obtain robust estimates, but also that insufficient quality control (QC) of SNPs can lead to spurious results and that too stringent QC is likely to remove real genetic signals. Our estimates show that common SNPs on commercially available genotyping chips capture significant variation contributing to liability for all three diseases. The estimated proportion of total variation tagged by all SNPs was 0.26 (SE 0.04) for ED, 0.24 (SE 0.03) for AD and 0.30 (SE 0.03) for MS. Further, we partitioned the genetic variance explained into five categories by a minor allele frequency (MAF), by chromosomes and gene annotation. We provide strong evidence that a substantial proportion of variation in liability is explained by common SNPs, and thereby give insights into the genetic architecture of the diseases.

Common SNPs explain a large proportion of the heritability for human height

SNPs discovered by genome-wide association studies (GWASs) account for only a small fraction of the genetic variation of complex traits in human populations. Where is the remaining heritability? We estimated the proportion of variance for human height explained by 294,831 SNPs genotyped on 3,925 unrelated individuals using a linear model analysis, and validated the estimation method with simulations based on the observed genotype data. We show that 45% of variance can be explained by considering all SNPs simultaneously. Thus, most of the heritability is not missing but has not previously been detected because the individual effects are too small to pass stringent significance tests. We provide evidence that the remaining heritability is due to incomplete linkage disequilibrium between causal variants and genotyped SNPs, exacerbated by causal variants having lower minor allele frequency than the SNPs explored to date.