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Sample records for disease longitudinal analysis

  1. Applied longitudinal analysis

    CERN Document Server

    Fitzmaurice, Garrett M; Ware, James H

    2012-01-01

    Praise for the First Edition "". . . [this book] should be on the shelf of everyone interested in . . . longitudinal data analysis.""-Journal of the American Statistical Association   Features newly developed topics and applications of the analysis of longitudinal data Applied Longitudinal Analysis, Second Edition presents modern methods for analyzing data from longitudinal studies and now features the latest state-of-the-art techniques. The book emphasizes practical, rather than theoretical, aspects of methods for the analysis of diverse types of lo

  2. Bayesian analysis of longitudinal Johne's disease diagnostic data without a gold standard test

    DEFF Research Database (Denmark)

    Wang, C.; Turnbull, B.W.; Nielsen, Søren Saxmose

    2011-01-01

    the posterior estimates of the model parameters that provide the basis for inference concerning the accuracy of the diagnostic procedure. Based on the Bayesian approach, the posterior probability distribution of the change-point onset time can be obtained and used as a criterion for infection diagnosis......-point process with a Weibull survival hazard function was used to model the progression of the hidden disease status. The model adjusted for the fixed effects of covariate variables and random effects of subject on the diagnostic testing procedure. Markov chain Monte Carlo methods were used to compute....... An application is presented to an analysis of ELISA and fecal culture test outcomes in the diagnostic testing of paratuberculosis (Johne's disease) for a Danish longitudinal study from January 2000 to March 2003. The posterior probability criterion based on the Bayesian model with 4 repeated observations has...

  3. Characterization of changes in serum anti-glycan antibodies in Crohn's disease--a longitudinal analysis.

    Directory of Open Access Journals (Sweden)

    Florian Rieder

    Full Text Available INTRODUCTION: Anti-glycan antibodies are a promising tool for differential diagnosis and disease stratification of patients with Crohn's disease (CD. We longitudinally assessed level and status changes of anti-glycan antibodies over time in individual CD patients as well as determinants of this phenomenon. METHODS: 859 serum samples derived from a cohort of 253 inflammatory bowel disease (IBD patients (207 CD, 46 ulcerative colitis (UC were tested for the presence of anti-laminarin (Anti-L, anti-chitin (Anti-C, anti-chitobioside (ACCA, anti-laminaribioside (ALCA, anti-mannobioside (AMCA and anti-Saccharomyces cerevisiae (gASCA antibodies by ELISA. All patients had at least two and up to eleven serum samples taken during the disease course. RESULTS: Median follow-up time for CD was 17.4 months (Interquartile range (IQR 8.0, 31.6 months and for UC 10.9 months (IQR 4.9, 21.0 months. In a subgroup of CD subjects marked changes in the overall immune response (quartile sum score and levels of individual markers were observed over time. The marker status (positive versus negative remained widely stable. Neither clinical phenotype nor NOD2 genotype was associated with the observed fluctuations. In a longitudinal analysis neither changes in disease activity nor CD behavior led to alterations in the levels of the glycan markers. The ability of the panel to discriminate CD from UC or its association with CD phenotypes remained stable during follow-up. In the serum of UC patients neither significant level nor status changes were observed. CONCLUSIONS: While the levels of anti-glycan antibodies fluctuate in a subgroup of CD patients the antibody status is widely stable over time.

  4. Longitudinal categorical data analysis

    CERN Document Server

    Sutradhar, Brajendra C

    2014-01-01

    This is the first book in longitudinal categorical data analysis with parametric correlation models developed based on dynamic relationships among repeated categorical responses. This book is a natural generalization of the longitudinal binary data analysis to the multinomial data setup with more than two categories. Thus, unlike the existing books on cross-sectional categorical data analysis using log linear models, this book uses multinomial probability models both in cross-sectional and longitudinal setups. A theoretical foundation is provided for the analysis of univariate multinomial responses, by developing models systematically for the cases with no covariates as well as categorical covariates, both in cross-sectional and longitudinal setups. In the longitudinal setup, both stationary and non-stationary covariates are considered. These models have also been extended to the bivariate multinomial setup along with suitable covariates. For the inferences, the book uses the generalized quasi-likelihood as w...

  5. The Weather and Ménière's Disease: A Longitudinal Analysis in the UK.

    Science.gov (United States)

    Schmidt, Wiebke; Sarran, Christophe; Ronan, Natalie; Barrett, George; Whinney, David J; Fleming, Lora E; Osborne, Nicholas J; Tyrrell, Jessica

    2017-02-01

    Changes in the weather influence symptom severity in Ménière's disease (MD). MD is an unpredictable condition that significantly impacts on quality of life. It is suggested that fluctuations in the weather, especially atmospheric pressure may influence the symptoms of MD. However, to date, limited research has investigated the impact of the weather on MD. In a longitudinal study, a mobile phone application collected data from 397 individuals (277 females and 120 males with an average age of 50 yr) from the UK reporting consultant-diagnosed MD. Daily symptoms (vertigo, aural fullness, tinnitus, hearing loss, and attack prevalence) and GPS locations were collected; these data were linked with Met Office weather data (including atmospheric pressure, humidity, temperature, visibility, and wind speed). Symptom severity and attack prevalence were reduced on days when atmospheric pressure was higher. When atmospheric pressure was below 1,013 hectopascals, the risk of an attack was 1.30 (95% confidence interval: 1.10, 1.54); when the humidity was above 90%, the risk of an attack was 1.26 (95% confidence interval 1.06, 1.49). This study provides the strongest evidence to date that changes in atmospheric pressure and humidity are associated with symptom exacerbation in MD. Improving our understanding of the role of weather and other environmental triggers in Ménière's may reduce the uncertainty associated with living with this condition, significantly contributing to improved quality of life.

  6. The Weather and Ménière’s Disease: A Longitudinal Analysis in the UK

    Science.gov (United States)

    Schmidt, Wiebke; Sarran, Christophe; Ronan, Natalie; Barrett, George; Whinney, David J.; Fleming, Lora E.; Osborne, Nicholas J.; Tyrrell, Jessica

    2016-01-01

    Hypothesis Changes in the weather influence symptom severity in Ménière’s disease (MD). Background MD is an unpredictable condition that significantly impacts on quality of life. It is suggested that fluctuations in the weather, especially atmospheric pressure may influence the symptoms of MD. However, to date, limited research has investigated the impact of the weather on MD. Methods In a longitudinal study, a mobile phone application collected data from 397 individuals (277 females and 120 males with an average age of 50 yr) from the UK reporting consultant-diagnosed MD. Daily symptoms (vertigo, aural fullness, tinnitus, hearing loss, and attack prevalence) and GPS locations were collected; these data were linked with Met Office weather data (including atmospheric pressure, humidity, temperature, visibility, and wind speed). Results Symptom severity and attack prevalence were reduced on days when atmospheric pressure was higher. When atmospheric pressure was below 1,013 hectopascals, the risk of an attack was 1.30 (95% confidence interval: 1.10, 1.54); when the humidity was above 90%, the risk of an attack was 1.26 (95% confidence interval 1.06, 1.49). Conclusion This study provides the strongest evidence to date that changes in atmospheric pressure and humidity are associated with symptom exacerbation in MD. Improving our understanding of the role of weather and other environmental triggers in Ménière’s may reduce the uncertainty associated with living with this condition, significantly contributing to improved quality of life. PMID:27861300

  7. The lower airway microbiota in early cystic fibrosis lung disease: a longitudinal analysis.

    Science.gov (United States)

    Frayman, Katherine B; Armstrong, David S; Carzino, Rosemary; Ferkol, Thomas W; Grimwood, Keith; Storch, Gregory A; Teo, Shu Mei; Wylie, Kristine M; Ranganathan, Sarath C

    2017-12-01

    In infants and young children with cystic fibrosis, lower airway infection and inflammation are associated with adverse respiratory outcomes. However, the role of lower airway microbiota in the pathogenesis of early cystic fibrosis lung disease remains uncertain. To assess the development of the lower airway microbiota over time in infants and young children with cystic fibrosis, and to explore its association with airway inflammation and pulmonary function at age 6 years. Serial, semi-annual bronchoscopies and bronchoalveolar lavage (BAL) procedures were performed in infants newly diagnosed with cystic fibrosis following newborn screening. Quantitative microbiological cultures and inflammatory marker (interleukin 8 and neutrophil elastase) measurements were undertaken contemporaneously. 16S ribosomal RNA gene sequencing was conducted on stored BAL samples. Spirometry results recorded at 6 years of age were extracted from medical records. Ninety-five BAL samples provided 16S ribosomal RNA gene data. These were collected from 48 subjects aged 1.2-78.3 months, including longitudinal samples from 27 subjects and 13 before age 6 months. The lower airway microbiota varied, but diversity decreased with advancing age. Detection of recognised cystic fibrosis bacterial pathogens was associated with reduced microbial diversity and greater lower airway inflammation. There was no association between the lower airway microbiota and pulmonary function at age 6 years. In infants with cystic fibrosis, the lower airway microbiota is dynamic. Dominance of the microbiota by recognised cystic fibrosis bacterial pathogens is associated with increased lower airway inflammation, however early microbial diversity is not associated with pulmonary function at 6 years of age. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  8. Longitudinal peripheral blood transcriptional analysis of a patient with severe Ebola virus disease.

    Science.gov (United States)

    Kash, John C; Walters, Kathie-Anne; Kindrachuk, Jason; Baxter, David; Scherler, Kelsey; Janosko, Krisztina B; Adams, Rick D; Herbert, Andrew S; James, Rebekah M; Stonier, Spencer W; Memoli, Matthew J; Dye, John M; Davey, Richard T; Chertow, Daniel S; Taubenberger, Jeffery K

    2017-04-12

    The 2013-2015 outbreak of Ebola virus disease in Guinea, Liberia, and Sierra Leone was unprecedented in the number of documented cases, but there have been few published reports on immune responses in clinical cases and their relationships with the course of illness and severity of Ebola virus disease. Symptoms of Ebola virus disease can include severe headache, myalgia, asthenia, fever, fatigue, diarrhea, vomiting, abdominal pain, and hemorrhage. Although experimental treatments are in development, there are no current U.S. Food and Drug Administration-approved vaccines or therapies. We report a detailed study of host gene expression as measured by microarray in daily peripheral blood samples collected from a patient with severe Ebola virus disease. This individual was provided with supportive care without experimental therapies at the National Institutes of Health Clinical Center from before onset of critical illness to recovery. Pearson analysis of daily gene expression signatures revealed marked gene expression changes in peripheral blood leukocytes that correlated with changes in serum and peripheral blood leukocytes, viral load, antibody responses, coagulopathy, multiple organ dysfunction, and then recovery. This study revealed marked shifts in immune and antiviral responses that preceded changes in medical condition, indicating that clearance of replicating Ebola virus from peripheral blood leukocytes is likely important for systemic viral clearance. Copyright © 2017, American Association for the Advancement of Science.

  9. Serum Uric Acid and Progression of Kidney Disease: A Longitudinal Analysis and Mini-Review.

    Directory of Open Access Journals (Sweden)

    Ching-Wei Tsai

    Full Text Available Increasing evidence supports the association between hyperuricemia and incident chronic kidney disease (CKD; however, there are conflicting data regarding the role of hyperuricemia in the progression of CKD. This study retrospectively assessed the longitudinal association between uric acid (UA level and CKD progression in a Chinese population lived in Taiwan.Patients with physician diagnosis of hyperuricemia or receiving urate-lowering therapy between 2003 and 2005 were identified in the electronic medical records (EMR of a tertiary medical center and were followed up until December 31, 2011. Patients were divided into four UA categories at the cut-off 6, 8, and 10 mg/dL. CKD progression was estimated by the change of estimated glomerular filtration rate (eGFR in the linear mixed models. Kidney failure was defined as an eGFR less than 15 mL/min/1.73 m2 or requiring renal replacement therapy.A total of 739 patients were analyzed. In the full-adjusted model, patients with a baseline UA level ≥6 mg/dL had greater decline in eGFR ((β = -9.6, 95% CI -16.1, -3.1, comparing to those with a UA level less than 6 mg/dL. When stratifying patients into four UA categories, all three hyperuricemia categories (UA6-8, 8-10, ≥10 mg/dL associated with a greater decline in eGFR over the follow-up period with an increasing dose-response, comparing to the lowest UA category. The risk of progression to renal failure increased 7% (hazard ratio 1.07, 95% CI 1.00, 1.14 for each 1mg/dL increase in baseline UA level. The influences of hyperuricemia on eGFR decline and the risk of kidney failure were more prominent in patients without proteinuria than those with proteinuria.Our study showed a higher uric acid level is associated with a significant rapid decline in eGFR and a higher risk of kidney failure, particularly in patients without proteinuria. Our findings suggest hyperuricemia is a potential modifiable factor of CKD progression.

  10. Scientific literature on infectious diseases affecting livestock animals, longitudinal worldwide bibliometric analysis.

    Science.gov (United States)

    Ducrot, Christian; Gautret, Marjolaine; Pineau, Thierry; Jestin, André

    2016-03-14

    The objectives of this bibliometric analysis of the scientific literature were to describe the research subjects and the international collaborations in the field of research on infectious diseases in livestock animals including fishes and honeybees. It was based on articles published worldwide from 2006 through 2013. The source of data was the Web of Science, Core collection(®) and only papers fully written in English were considered. Queries were built that combined 130 descriptors related to animal species and 1213 descriptors related to diseases and pathogens. To refine and assess the accuracy of the extracted database, supplementary filters were applied to discard non-specific terms and neighbouring topics, and numerous tests were carried out on samples. For pathogens, annotation was done using a thematic terminology established to link each disease with its corresponding pathogen, which was in turn classified according to its family. A total of 62,754 articles were published in this field during this 8-year period. The average annual growth rate of the number of papers was 5%. This represents the reference data to which we compared the average annual growth rate of articles produced in each of the sub-categories that we defined. Thirty-seven percent of the papers were dedicated to ruminant diseases. Poultry, pigs and fishes were covered by respectively 21, 13 and 14% of the total. Thirty-seven percent of papers concerned bacteria, 33% viruses, 19% parasites, 2% prions, the remaining being multi-pathogens. Research on virology, especially on pigs and poultry, is increasing faster than the average. There also is increasing interest in monogastric species, fish and bees. The average annual growth rate for Asia was 10%, which is high compared to 3% for Europe and 2% for the Americas, indicating that Asia is currently playing a leading role in this field. There is a well established network of international collaborations. For 75% of the papers, the co

  11. Test-retest reliability and longitudinal analysis of automated hippocampal subregion volumes in healthy ageing and Alzheimer's disease populations.

    Science.gov (United States)

    Worker, Amanda; Dima, Danai; Combes, Anna; Crum, William R; Streffer, Johannes; Einstein, Steven; Mehta, Mitul A; Barker, Gareth J; C R Williams, Steve; O'daly, Owen

    2018-04-01

    The hippocampal formation is a complex brain structure that is important in cognitive processes such as memory, mood, reward processing and other executive functions. Histological and neuroimaging studies have implicated the hippocampal region in neuropsychiatric disorders as well as in neurodegenerative diseases. This highly plastic limbic region is made up of several subregions that are believed to have different functional roles. Therefore, there is a growing interest in imaging the subregions of the hippocampal formation rather than modelling the hippocampus as a homogenous structure, driving the development of new automated analysis tools. Consequently, there is a pressing need to understand the stability of the measures derived from these new techniques. In this study, an automated hippocampal subregion segmentation pipeline, released as a developmental version of Freesurfer (v6.0), was applied to T1-weighted magnetic resonance imaging (MRI) scans of 22 healthy older participants, scanned on 3 separate occasions and a separate longitudinal dataset of 40 Alzheimer's disease (AD) patients. Test-retest reliability of hippocampal subregion volumes was assessed using the intra-class correlation coefficient (ICC), percentage volume difference and percentage volume overlap (Dice). Sensitivity of the regional estimates to longitudinal change was estimated using linear mixed effects (LME) modelling. The results show that out of the 24 hippocampal subregions, 20 had ICC scores of 0.9 or higher in both samples; these regions include the molecular layer, granule cell layer of the dentate gyrus, CA1, CA3 and the subiculum (ICC > 0.9), whilst the hippocampal fissure and fimbria had lower ICC scores (0.73-0.88). Furthermore, LME analysis of the independent AD dataset demonstrated sensitivity to group and individual differences in the rate of volume change over time in several hippocampal subregions (CA1, molecular layer, CA3, hippocampal tail, fissure and presubiculum

  12. Power analysis to detect treatment effects in longitudinal clinical trials for Alzheimer's disease.

    Science.gov (United States)

    Huang, Zhiyue; Muniz-Terrera, Graciela; Tom, Brian D M

    2017-09-01

    Assessing cognitive and functional changes at the early stage of Alzheimer's disease (AD) and detecting treatment effects in clinical trials for early AD are challenging. Under the assumption that transformed versions of the Mini-Mental State Examination, the Clinical Dementia Rating Scale-Sum of Boxes, and the Alzheimer's Disease Assessment Scale-Cognitive Subscale tests'/components' scores are from a multivariate linear mixed-effects model, we calculated the sample sizes required to detect treatment effects on the annual rates of change in these three components in clinical trials for participants with mild cognitive impairment. Our results suggest that a large number of participants would be required to detect a clinically meaningful treatment effect in a population with preclinical or prodromal Alzheimer's disease. We found that the transformed Mini-Mental State Examination is more sensitive for detecting treatment effects in early AD than the transformed Clinical Dementia Rating Scale-Sum of Boxes and Alzheimer's Disease Assessment Scale-Cognitive Subscale. The use of optimal weights to construct powerful test statistics or sensitive composite scores/endpoints can reduce the required sample sizes needed for clinical trials. Consideration of the multivariate/joint distribution of components' scores rather than the distribution of a single composite score when designing clinical trials can lead to an increase in power and reduced sample sizes for detecting treatment effects in clinical trials for early AD.

  13. Longitudinal analysis of quality of life in patients with undifferentiated connective tissue diseases

    Directory of Open Access Journals (Sweden)

    Iudici M

    2017-02-01

    Full Text Available Michele Iudici, Rosaria Irace, Antonella Riccardi, Giovanna Cuomo, Serena Vettori, Gabriele Valentini Rheumatology Section, Department of Clinical and Experimental Medicine, Second University of Naples, Naples, Italy Introduction/objectives: To prospectively assess the quality of life (QoL of patients affected by undifferentiated connective tissue diseases (UCTDs and to identify factors associated with changes over time.Patients and methods: A total of 46 consecutive UCTD patients completed the Short-Form 36 (SF-36 questionnaire at presentation and then yearly. At each 6-month visit, all patients underwent a detailed history taking and a laboratory and physical assessment, in order to follow the evolution of the disease over time and to assess the the co-existence of fibromyalgia.Results: At presentation, scores lower than the average of the general population were detected in 34 (74% and 41 (89% patients in the physical and mental domains, respectively. No difference between patients with and without Raynaud’s phenomenon was detected. Fibromyalgia was the only independent variable associated with an impaired physical component summary score (p = 0.0009. No patient feature was found to be associated with the basal mental component summary score. During 24 months of follow-up, a significant improvement (ie, a change ≥5 from baseline in physical component summary and mental component summary scores was observed in 14 (33.3% and 20 (43.4% patients, respectively. Patients who significantly improved in the physical domain more frequently had a history of glucocorticoids intake (p < 0.001, while those who improved in the mental component more frequently had a history of either glucocorticoids (p = 0.043 or immunosuppressors (p = 0.037 intake during follow-up.Conclusion: UCTD patients perceive a worse QoL, regardless of Raynaud’s phenomenon Fibromyalgia is one of the major contributors of physical QoL, whereas no factor influencing

  14. Correspondence analysis of longitudinal data

    NARCIS (Netherlands)

    Van der Heijden, P.G.M.|info:eu-repo/dai/nl/073087998

    2005-01-01

    Correspondence analysis is an exploratory tool for the analysis of associations between categorical variables, the results of which may be displayed graphically. For longitudinal data with two time points, an analysis of the transition matrix (showing the relative frequencies for pairs of

  15. Longitudinal Transcriptome Analysis Reveals a Sustained Differential Gene Expression Signature in Patients Treated for Acute Lyme Disease.

    Science.gov (United States)

    Bouquet, Jerome; Soloski, Mark J; Swei, Andrea; Cheadle, Chris; Federman, Scot; Billaud, Jean-Noel; Rebman, Alison W; Kabre, Beniwende; Halpert, Richard; Boorgula, Meher; Aucott, John N; Chiu, Charles Y

    2016-02-12

    Lyme disease is a tick-borne illness caused by the bacterium Borrelia burgdorferi, and approximately 10 to 20% of patients report persistent symptoms lasting months to years despite appropriate treatment with antibiotics. To gain insights into the molecular basis of acute Lyme disease and the ensuing development of post-treatment symptoms, we conducted a longitudinal transcriptome study of 29 Lyme disease patients (and 13 matched controls) enrolled at the time of diagnosis and followed for up to 6 months. The differential gene expression signature of Lyme disease following the acute phase of infection persisted for at least 3 weeks and had fewer than 44% differentially expressed genes (DEGs) in common with other infectious or noninfectious syndromes. Early Lyme disease prior to antibiotic therapy was characterized by marked upregulation of Toll-like receptor signaling but lack of activation of the inflammatory T-cell apoptotic and B-cell developmental pathways seen in other acute infectious syndromes. Six months after completion of therapy, Lyme disease patients were found to have 31 to 60% of their pathways in common with three different immune-mediated chronic diseases. No differential gene expression signature was observed between Lyme disease patients with resolved illness to those with persistent symptoms at 6 months post-treatment. The identification of a sustained differential gene expression signature in Lyme disease suggests that a panel of selected human host-based biomarkers may address the need for sensitive clinical diagnostics during the "window period" of infection prior to the appearance of a detectable antibody response and may also inform the development of new therapeutic targets. Lyme disease is the most common tick-borne infection in the United States, and some patients report lingering symptoms lasting months to years despite antibiotic treatment. To better understand the role of the human host response in acute Lyme disease and the

  16. A longitudinal analysis of the effect of nonmedical exemption law and vaccine uptake on vaccine-targeted disease rates.

    Science.gov (United States)

    Yang, Y Tony; Debold, Vicky

    2014-02-01

    We assessed how nonmedical exemption (NME) laws and annual uptake of vaccines required for school or daycare entry affect annual incidence rates for 5 vaccine-targeted diseases: pertussis, measles, mumps, Haemophilus influenzae type B, and hepatitis B. We employed longitudinal mixed-effects models to examine 2001-2008 vaccine-targeted disease data obtained from the National Notifiable Disease Surveillance System. Key explanatory variables were state-level vaccine-specific uptake rates from the National Immunization Survey and a state NME law restrictiveness level. NME law restrictiveness and vaccine uptake were not associated with disease incidence rate for hepatitis B, Haemophilus influenzae type B, measles, or mumps. Pertussis incidence rate, however, was negatively associated with NME law restrictiveness (b = -0.20; P = .03) and diphtheria-pertussis-tetanus vaccine uptake (b = -0.01; P = .05). State NME laws and vaccine uptake rates did not appear to influence lower-incidence diseases but may influence reported disease rates for higher-incidence diseases. If all states increased their NME law restrictiveness by 1 level and diphtheria-pertussis-tetanus uptake by 1%, national annual pertussis cases could decrease by 1.14% (171 cases) and 0.04% (5 cases), respectively.

  17. Longitudinal Transcriptome Analysis Reveals a Sustained Differential Gene Expression Signature in Patients Treated for Acute Lyme Disease

    Science.gov (United States)

    Bouquet, Jerome; Soloski, Mark J.; Swei, Andrea; Cheadle, Chris; Federman, Scot; Billaud, Jean-Noel; Rebman, Alison W.; Kabre, Beniwende; Halpert, Richard; Boorgula, Meher

    2016-01-01

    ABSTRACT Lyme disease is a tick-borne illness caused by the bacterium Borrelia burgdorferi, and approximately 10 to 20% of patients report persistent symptoms lasting months to years despite appropriate treatment with antibiotics. To gain insights into the molecular basis of acute Lyme disease and the ensuing development of post-treatment symptoms, we conducted a longitudinal transcriptome study of 29 Lyme disease patients (and 13 matched controls) enrolled at the time of diagnosis and followed for up to 6 months. The differential gene expression signature of Lyme disease following the acute phase of infection persisted for at least 3 weeks and had fewer than 44% differentially expressed genes (DEGs) in common with other infectious or noninfectious syndromes. Early Lyme disease prior to antibiotic therapy was characterized by marked upregulation of Toll-like receptor signaling but lack of activation of the inflammatory T-cell apoptotic and B-cell developmental pathways seen in other acute infectious syndromes. Six months after completion of therapy, Lyme disease patients were found to have 31 to 60% of their pathways in common with three different immune-mediated chronic diseases. No differential gene expression signature was observed between Lyme disease patients with resolved illness to those with persistent symptoms at 6 months post-treatment. The identification of a sustained differential gene expression signature in Lyme disease suggests that a panel of selected human host-based biomarkers may address the need for sensitive clinical diagnostics during the “window period” of infection prior to the appearance of a detectable antibody response and may also inform the development of new therapeutic targets. PMID:26873097

  18. Longitudinal Meta-analysis

    NARCIS (Netherlands)

    Hox, J.J.; Maas, C.J.M.; Lensvelt-Mulders, G.J.L.M.

    2004-01-01

    The goal of meta-analysis is to integrate the research results of a number of studies on a specific topic. Characteristic for meta-analysis is that in general only the summary statistics of the studies are used and not the original data. When the published research results to be integrated

  19. Longitudinal morphometric MRI study of Alzheimer's disease

    International Nuclear Information System (INIS)

    Ogomori, Koji; Takano, Koichi; Kuwabara, Yasuo; Nakano, Seigo; Nawata, Hideyuki; Yano, Rika; Nishimura, Ryoji; Takita, Masashi

    2009-01-01

    A longitudinal morphometric MRI study of Alzheimer's disease (AD) was conducted to determine the relationship between the progression of the symptoms and the progression of the brain atrophy. The Voxel-based Specific Regional Analysis System for Alzheimer's Disease (VSRAD), developed by Matsuda et al. was used as a method of morphometry to perform the statistical MR image analysis. Thirty-eight patients of AD patients were investigated with VSRAD. These patients were divided into two groups according to the progression of symptoms based on a clinical evaluation. One group was the progress group (20 patients), while the other group was the stable group (18 patients) for comparison. The relationship was investigated between the speed of the symptomatic progression and the change in each VSRAD indicator. Consequently, the entorhinal Z-score and the entorhinal atrophy rate showed a correlation with the speed of the symptomatic progression. The increase of the entorhinal Z-score in the follow-up was larger in the progress group than that in the stable group (0.65/1.28 years in the progress group and 0.05/1.26 years in the stable group.). These results suggest that a rapid symptomatic progression in an AD patient accompanies the rapid progression of atrophy in the entorhinal cortex. (author)

  20. The association of periodontal disease with kidney function decline: a longitudinal retrospective analysis of the MrOS dental study.

    Science.gov (United States)

    Grubbs, Vanessa; Vittinghoff, Eric; Taylor, George; Kritz-Silverstein, Donna; Powe, Neil; Bibbins-Domingo, Kirsten; Ishani, Areef; Cummings, Steven R

    2016-03-01

    Identifying modifiable risk factors for chronic kidney disease (CKD) is essential for reducing its burden. Periodontal disease is common, modifiable and has been implicated as a novel potential CKD risk factor, but evidence of its association with kidney function decline over time is limited. In a longitudinal retrospective cohort of 761 elderly men with preserved kidney function [estimated glomerular filtration rate > 60 mL/min/1.73 m(2) using a calibrated creatinine and cystatin C (eGFRcr-cys) equation] at baseline, we performed multivariable Poisson's regression to examine the association of severe periodontal disease with incident CKD, defined as incident eGFRcr-cys 5% annualized) eGFRcr-cys decline. Severe periodontal disease was defined in two ways: (i) ≥5 mm proximal attachment loss in 30% of teeth examined (European Workshop in Periodontology Group C, European Workshop); and (ii) 2+ interproximal sites with attachment loss ≥6 mm and 1+ interproximal sites with probing depth ≥5 mm (Centers for Disease Control/American Academy of Periodontology, CDC/AAP). At baseline, the mean age was 73.4 (SD 4.8) years, the median eGFRcr-cys was 82.4 mL/min/1.73 m(2), and 35.5 and 25.4% of participants had severe periodontal disease by European Workshop and CDC/AAP criteria, respectively. After a mean follow-up of 4.9 years (SD 0.3), 56 (7.4%) participants had incident CKD. Severe periodontal disease was associated with a 2-fold greater rate of incident CKD [incidence rate ratio (IRR) 2.01 (1.21-3.44), P = 0.007] after adjusting for confounders compared with not severe periodontal disease by European Workshop criteria but did not reach statistical significance by CDC/AAP criteria [IRR 1.10 (0.63-1.91), P = 0.9]. Severe periodontal disease may be associated with incident clinically significant kidney function decline among a cohort of elderly men. © The Author 2015. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

  1. Longitudinal analysis of the behavioral phenotype in a novel transgenic rat model of early stages of Alzheimer's disease.

    Science.gov (United States)

    Galeano, Pablo; Martino Adami, Pamela V; Do Carmo, Sonia; Blanco, Eduardo; Rotondaro, Cecilia; Capani, Francisco; Castaño, Eduardo M; Cuello, A Claudio; Morelli, Laura

    2014-01-01

    Intraneuronal accumulation of amyloid β (iAβ) has been linked to mild cognitive impairment that may precede Alzheimer's disease (AD) onset. This neuropathological trait was recently mimicked in a novel animal model of AD, the hemizygous transgenic McGill-R-Thy1-APP (Tg(+/-)) rat. The characterization of the behavioral phenotypes in this animal model could provide a baseline of efficacy for earlier therapeutic interventions. The aim of the present study was to undertake a longitudinal study of Aβ accumulation and a comprehensive behavioral evaluation of this transgenic rat model. We assessed exploratory activity, anxiety-related behaviors, recognition memory, working memory, spatial learning and reference memory at 3, 6, and 12 months of age. In parallel, we measured Aβ by ELISA, Western blots and semiquantitative immunohistochemistry in hippocampal samples. SDS-soluble Aβ peptide accumulated at low levels (~9 pg/mg) without differences among ages. However, Western blots showed SDS-resistant Aβ oligomers (~30 kDa) at 6 and 12 months, but not at 3 months. When compared to wild-type (WT), male Tg(+/-) rats exhibited a spatial reference memory deficit in the Morris Water Maze (MWM) as early as 3 months of age, which persisted at 6 and 12 months. In addition, Tg(+/-) rats displayed a working memory impairment in the Y-maze and higher anxiety levels in the Open Field (OF) at 6 and 12 months of age, but not at 3 months. Exploratory activity in the OF was similar to that of WT at all-time points. Spatial learning in the MWM and the recognition memory, as assessed by the Novel Object Recognition Test, were unimpaired at any time point. The data from the present study demonstrate that the hemizygous transgenic McGill-R-Thy1-APP rat has a wide array of behavioral and cognitive impairments from young adulthood to middle-age. The low Aβ burden and early emotional and cognitive deficits in this transgenic rat model supports its potential use for drug discovery purposes in

  2. Qualitative Analysis of Mini Mental State Examination Pentagon in Vascular Dementia and Alzheimer's Disease: A Longitudinal Explorative Study.

    Science.gov (United States)

    Lo Buono, Viviana; Bonanno, Lilla; Corallo, Francesco; Foti, Maria; Palmeri, Rosanna; Angela, Marra; Di Lorenzo, Giuseppe; Todaro, Antonino; Bramanti, Placido; Bramanti, Alessia; Marino, Silvia

    2018-06-01

    Vascular dementia and Alzheimer's disease are the most diffuse forms of dementia. Sometimes, they are difficult to distinguish due to overlaps in symptomatology, pathophysiology, and comorbidity. Visual constructive apraxia is very common in dementia and impairment in these abilities can provide clinical information for differential diagnosis. All patients underwent Mini Mental State Examination (MMSE) at basal visit (T0) and after 1 year (T1). We analyzed differences in Qualitative Scoring Method for the Pentagon Copying Test and we explored the visual constructive apraxia evolution in these 2 types of dementia. In intragroup analysis, we found a significant difference in each group between T0 and T1 in MMSE score (P < .001) and total qualitative scores (P < .001). In intergroup analysis, at T0, we found significance difference in total qualitative scores (P < .001), in numbers of angles (P = .005), in distance/intersection (P < .001), in closure/opening (P = .01), in rotation (P < .001), and in closing-in (P < .001). At T1, we found significance difference in total qualitative scores (P < .001), in particular, in numbers of angles (P < .001), in distance/intersection (P < .001), in closure/opening (P < .001), in rotation (P < .001), and in closing-in (P < .001). The total score showed the highest classification accuracy (.90, 95%CI = .81-0.96) in differentiating patients with Alzheimer's disease from patients with vascular dementia. The optimal threshold value was k = 5. with .84 (95%CI = .69-0.93) sensitivity and .81 (95%CI = .64-0.93) specificity. Patients with vascular dementia showed more accuracy errors and graphic difficulties than patients with Alzheimer's disease. Qualitative analysis of copy provided a sensitive measure of visual constructive abilities in differentiating dementias, underlining a particularly vulnerability of visuoconstructive functions in vascular dementia compared

  3. Multivariate mixed linear model analysis of longitudinal data: an information-rich statistical technique for analyzing disease resistance data

    Science.gov (United States)

    The mixed linear model (MLM) is currently among the most advanced and flexible statistical modeling techniques and its use in tackling problems in plant pathology has begun surfacing in the literature. The longitudinal MLM is a multivariate extension that handles repeatedly measured data, such as r...

  4. A longitudinal analysis of the risk factors for diabetes and coronary heart disease in the Framingham Offspring Study

    Directory of Open Access Journals (Sweden)

    Bhargava Alok

    2003-04-01

    Full Text Available Abstract Background The recent trends in sedentary life-styles and weight gain are likely to contribute to chronic conditions such as hypertension, diabetes, and cardiovascular diseases. The temporal sequence and pathways underlying these conditions can be modeled using the knowledge from the biomedical and social sciences. Methods The Framingham Offspring Study in the U.S. collected information on 5124 subjects at baseline, and 8, 12, 16, and 20 years after the baseline. Dynamic random effects models were estimated for the subjects' weight, LDL and HDL cholesterol, and blood pressure using 4 time observations. Logistic and probit models were estimated for the probability of diabetes and coronary heart disease (CHD events. Results The subjects' age, physical activity, alcohol consumption, and cigarettes smoked were important predictors of the risk factors. Moreover, weight and height were found to differentially affect the probabilities of diabetes and CHD events; body weight was positively associated with the risk of diabetes while taller individuals had lower risk of CHD events. Conclusion The results showed the importance of joint modeling of body weight, LDL and HDL cholesterol, and blood pressure that are risk factors for diabetes and CHD events. Lower body weight and LDL concentrations and higher HDL levels achieved via physical exercise are likely to reduce diabetes and CHD events.

  5. Thyrotropin and free thyroxine levels and coronary artery disease: cross-sectional analysis of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

    Science.gov (United States)

    de Miranda, E J F Peixoto; Bittencourt, M S; Staniak, H L; Sharovsky, R; Pereira, A C; Foppa, M; Santos, I S; Lotufo, P A; Benseñor, I M

    2018-03-15

    Data on the association between subclinical thyroid dysfunction and coronary artery disease (CAD) is scarce. We aimed to analyze the association between thyroid function and CAD using baseline data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). We included subjects with normal thyroid function (0.4-4.0 mIU/L, and normal free thyroxine, FT4, or 0.8 to 1.9 ng/dL), subclinical hypothyroidism (SCHypo; TSH>4.0 mIU/L and normal FT4), and subclinical hyperthyroidism (SCHyper; TSH4, and segment severity score (SSS) >4 of coronary arteries as the dependent variables, and quintiles of TSH and FT4 as the independent variables, adjusted for demographical data and cardiovascular risk factors. We included 767 subjects, median age 58 years (IQR=55-63), 378 (49.3%) women, 697 euthyroid (90.9%), 57 (7.4%) with SCHypo, and 13 (1.7%) with SCHyper. No association between TSH and FT4 quintiles and CAD prevalence was noted. Similarly, no association between TSH levels and the extent or severity of CAD, represented by SIS>4 and SSS>4 were seen. Restricting analysis to euthyroid subjects did not alter the results. TSH levels were not significantly associated with the presence, extent, or severity of CAD in a middle-aged healthy population.

  6. Bayesian Nonparametric Longitudinal Data Analysis.

    Science.gov (United States)

    Quintana, Fernando A; Johnson, Wesley O; Waetjen, Elaine; Gold, Ellen

    2016-01-01

    Practical Bayesian nonparametric methods have been developed across a wide variety of contexts. Here, we develop a novel statistical model that generalizes standard mixed models for longitudinal data that include flexible mean functions as well as combined compound symmetry (CS) and autoregressive (AR) covariance structures. AR structure is often specified through the use of a Gaussian process (GP) with covariance functions that allow longitudinal data to be more correlated if they are observed closer in time than if they are observed farther apart. We allow for AR structure by considering a broader class of models that incorporates a Dirichlet Process Mixture (DPM) over the covariance parameters of the GP. We are able to take advantage of modern Bayesian statistical methods in making full predictive inferences and about characteristics of longitudinal profiles and their differences across covariate combinations. We also take advantage of the generality of our model, which provides for estimation of a variety of covariance structures. We observe that models that fail to incorporate CS or AR structure can result in very poor estimation of a covariance or correlation matrix. In our illustration using hormone data observed on women through the menopausal transition, biology dictates the use of a generalized family of sigmoid functions as a model for time trends across subpopulation categories.

  7. Detection of Obstructive Coronary Artery Disease Using Peak Systolic Global Longitudinal Strain Derived by Two-Dimensional Speckle-Tracking: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Liou, Kevin; Negishi, Kazuaki; Ho, Suyen; Russell, Elizabeth A; Cranney, Greg; Ooi, Sze-Yuan

    2016-08-01

    Global longitudinal strain (GLS) is well validated and has important applications in contemporary clinical practice. The aim of this analysis was to evaluate the accuracy of resting peak GLS in the diagnosis of obstructive coronary artery disease (CAD). A systematic literature search was performed through July 2015 using four databases. Data were extracted independently by two authors and correlated before analyses. Using a random-effect model, the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and summary area under the curve for GLS were estimated with their respective 95% CIs. Screening of 1,669 articles yielded 10 studies with 1,385 patients appropriate for inclusion in the analysis. The mean age and left ventricular ejection fraction were 59.9 years and 61.1%. On the whole, 54.9% and 20.9% of the patients had hypertension and diabetes, respectively. Overall, abnormal GLS detected moderate to severe CAD with a pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of 74.4%, 72.1%, 2.9, and 0.35 respectively. The area under the curve and diagnostic odds ratio were 0.81 and 8.5. The mean values of GLS for those with and without CAD were -16.5% (95% CI, -15.8% to -17.3%) and -19.7% (95% CI, -18.8% to -20.7%), respectively. Subgroup analyses for patients with severe CAD and normal left ventricular ejection fractions yielded similar results. Current evidence supports the use of GLS in the detection of moderate to severe obstructive CAD in symptomatic patients. GLS may complement existing diagnostic algorithms and act as an early adjunctive marker of cardiac ischemia. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

  8. Birth order and paediatric allergic disease: A nationwide longitudinal survey.

    Science.gov (United States)

    Kikkawa, T; Yorifuji, T; Fujii, Y; Yashiro, M; Okada, A; Ikeda, M; Doi, H; Tsukahara, H

    2018-05-01

    Environmental factors seem to be related to the incidence of allergic disease. Children with a later birth order are often exposed to environments, where pathogens and endotoxins can be found, and thus have a higher risk of developing infectious diseases. Therefore, birth order is regarded as an indicator that reflects post-natal environment. However, longitudinal studies are limited on this subject. This study sought to elucidate the relationships between birth order and allergic disease. From a nationwide longitudinal study that followed children born in 2001 (n = 47 015), we selected doctors' visits for 3 types of allergic disease-bronchial asthma, food allergy and atopic dermatitis-from infancy to 12 years of age and conducted binomial log-linear regression analysis to evaluate the associations between birth order and these diseases. We adjusted for the child and parental factors and estimated risk ratio (RR) and 95% confidence interval (CI) for each outcome. The associations between birth order and bronchial asthma were diverse; later birth order increased the risk in early childhood, but decreased the risks during school age. For example, the adjusted RR comparing third-born or higher and first-born children was 1.19 (95% CI, 1.05-1.35) between 30 and 42 months of age, but was 0.76 (95% CI, 0.65-0.89) between 10 and 11 years. Later birth order was generally protective for food allergy but increased the risk of atopic dermatitis. The influence of birth order depended on the type of allergic disease and the childhood period. Childhood is unique in terms of physical and immunological development, and the immune response to the post-natal environment in childhood appears to be heterogeneous. © 2018 John Wiley & Sons Ltd.

  9. Incentivised chronic disease management and the inverse equity hypothesis: findings from a longitudinal analysis of Scottish primary care practice-level data.

    Science.gov (United States)

    Lowrie, Richard; McConnachie, Alex; Williamson, Andrea E; Kontopantelis, Evangelos; Forrest, Marie; Lannigan, Norman; Mercer, Stewart W; Mair, Frances S

    2017-04-11

    The inverse equity hypothesis asserts that new health policies initially widen inequality, then attenuate inequalities over time. Since 2004, the UK's pay-for-performance scheme for chronic disease management (CDM) in primary care general practices (the Quality and Outcomes Framework) has permitted practices to except (exclude) patients from attending annual CDM reviews, without financial penalty. Informed dissent (ID) is one component of exception rates, applied to patients who have not attended due to refusal or non-response to invitations. 'Population achievement' describes the proportion receiving care, in relation to those eligible to receive it, including excepted patients. Examination of exception reporting (including ID) and population achievement enables the equity impact of the UK pay-for-performance contract to be assessed. We conducted a longitudinal analysis of practice-level rates and of predictors of ID, overall exceptions and population achievement for CDM to examine whether the inverse equity hypothesis holds true. We carried out a retrospective, longitudinal study using routine primary care data, analysed by multilevel logistic regression. Data were extracted from 793 practices (83% of Scottish general practices) serving 4.4 million patients across Scotland from 2010/2011 to 2012/2013, for 29 CDM indicators covering 11 incentivised diseases. This provided 68,991 observations, representing a total of 15 million opportunities for exception reporting. Across all observations, the median overall exception reporting rate was 7.0% (7.04% in 2010-2011; 7.02% in 2011-2012 and 6.92% in 2012-2013). The median non-attendance rate due to ID was 0.9% (0.76% in 2010-2011; 0.88% in 2011-2012 and 0.96% in 2012-2013). Median population achievement was 83.5% (83.51% in 2010-2011; 83.41% in 2011-2012 and 83.63% in 2012-2013). The odds of ID reporting in 2012/2013 were 16.0% greater than in 2010/2011 (p rural practices reported lower levels of non-attendance due to

  10. Association Between Change in Body Mass Index, Unified Parkinson's Disease Rating Scale Scores, and Survival Among Persons With Parkinson Disease: Secondary Analysis of Longitudinal Data From NINDS Exploratory Trials in Parkinson Disease Long-term Study 1.

    Science.gov (United States)

    Wills, Anne-Marie A; Pérez, Adriana; Wang, Jue; Su, Xiao; Morgan, John; Rajan, Suja S; Leehey, Maureen A; Pontone, Gregory M; Chou, Kelvin L; Umeh, Chizoba; Mari, Zoltan; Boyd, James

    2016-03-01

    Greater body mass index (BMI, calculated as weight in kilograms divided by height in meters squared) is associated with improved survival among persons with Huntington disease or amyotrophic lateral sclerosis. Weight loss is common among persons with Parkinson disease (PD) and is associated with worse quality of life. To explore the association between change in BMI, Unified Parkinson's Disease Rating Scale (UPDRS) motor and total scores, and survival among persons with PD and to test whether there is a positive association between BMI at randomization and survival. Secondary analysis (from May 27, 2014, to October 13, 2015) of longitudinal data (3-6 years) from 1673 participants who started the National Institute of Neurological Disorders and Stroke Exploratory Trials in PD Long-term Study-1 (NET-PD LS-1). This was a double-blind randomized placebo-controlled clinical trial of creatine monohydrate (10 g/d) that was performed at 45 sites throughout the United States and Canada. Participants with early (within 5 years of diagnosis) and treated (receiving dopaminergic therapy) PD were enrolled from March 2007 to May 2010 and followed up until September 2013. Change across time in motor UPDRS score, change across time in total UPDRS score, and time to death. Generalized linear mixed models were used to estimate the effect of BMI on the change in motor and total UPDRS scores after controlling for covariates. Survival was analyzed using Cox proportional hazards models of time to death. A participant's BMI was measured at randomization, and BMI trajectory groups were classified according to whether participants experienced weight loss ("decreasing BMI"), weight stability ("stable BMI"), or weight gain ("increasing BMI") during the study. Of the 1673 participants (mean [SD] age, 61.7 [9.6] years; 1074 [64.2%] were male), 158 (9.4%) experienced weight loss (decreasing BMI), whereas 233 (13.9%) experienced weight gain (increasing BMI). After adjusting for covariates, we

  11. Longitudinal Study of Gray Matter Changes in Parkinson Disease.

    Science.gov (United States)

    Jia, X; Liang, P; Li, Y; Shi, L; Wang, D; Li, K

    2015-12-01

    The pathology of Parkinson disease leads to morphological brain volume changes. So far, the progressive gray matter volume change across time specific to patients with Parkinson disease compared controls remains unclear. Our aim was to investigate the pattern of gray matter changes in patients with Parkinson disease and to explore the progressive gray matter volume change specific to patients with Parkinson disease with disease progression by using voxel-based morphometry analysis. Longitudinal cognitive assessment and structural MR imaging of 89 patients with Parkinson disease (62 men) and 55 healthy controls (33 men) were from the Parkinson's Progression Markers Initiative data base, including the initial baseline and 12-month follow-up data. Two-way analysis of covariance was performed with covariates of age, sex, years of education, imaging data from multiple centers, and total intracranial volume by using Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra tool from SPM8 software. Gray matter volume changes for patients with Parkinson disease were detected with decreased gray matter volume in the frontotemporoparietal areas and the bilateral caudate, with increased gray matter volume in the bilateral limbic/paralimbic areas, medial globus pallidus/putamen, and the right occipital cortex compared with healthy controls. Progressive gray matter volume decrease in the bilateral caudate was found for both patients with Parkinson disease and healthy controls, and this caudate volume was positively associated with cognitive ability for both groups. The progressive gray matter volume increase specific to the patients with Parkinson disease was identified close to the left ventral lateral nucleus of thalamus, and a positive relationship was found between the thalamic volume and the tremor scores in a subgroup with tremor-dominant patients with Parkinson disease. The observed progressive changes in gray matter volume in Parkinson disease may provide

  12. Coronary heart disease index based on longitudinal electrocardiography

    Science.gov (United States)

    Townsend, J. C.; Cronin, J. P.

    1977-01-01

    A coronary heart disease index was developed from longitudinal ECG (LCG) tracings to serve as a cardiac health measure in studies of working and, essentially, asymptomatic populations, such as pilots and executives. For a given subject, the index consisted of a composite score based on the presence of LCG aberrations and weighted values previously assigned to them. The index was validated by correlating it with the known presence or absence of CHD as determined by a complete physical examination, including treadmill, resting ECG, and risk factor information. The validating sample consisted of 111 subjects drawn by a stratified-random procedure from 5000 available case histories. The CHD index was found to be significantly more valid as a sole indicator of CHD than the LCG without the use of the index. The index consistently produced higher validity coefficients in identifying CHD than did treadmill testing, resting ECG, or risk factor analysis.

  13. Longitudinal analysis of mouse SDOCT volumes

    Science.gov (United States)

    Antony, Bhavna J.; Carass, Aaron; Lang, Andrew; Kim, Byung-Jin; Zack, Donald J.; Prince, Jerry L.

    2017-03-01

    Spectral-domain optical coherence tomography (SDOCT), in addition to its routine clinical use in the diagnosis of ocular diseases, has begun to fund increasing use in animal studies. Animal models are frequently used to study disease mechanisms as well as to test drug efficacy. In particular, SDOCT provides the ability to study animals longitudinally and non-invasively over long periods of time. However, the lack of anatomical landmarks makes the longitudinal scan acquisition prone to inconsistencies in orientation. Here, we propose a method for the automated registration of mouse SDOCT volumes. The method begins by accurately segmenting the blood vessels and the optic nerve head region in the scans using a pixel classification approach. The segmented vessel maps from follow-up scans were registered using an iterative closest point (ICP) algorithm to the baseline scan to allow for the accurate longitudinal tracking of thickness changes. Eighteen SDOCT volumes from a light damage model study were used to train a random forest utilized in the pixel classification step. The area under the curve (AUC) in a leave-one-out study for the retinal blood vessels and the optic nerve head (ONH) was found to be 0.93 and 0.98, respectively. The complete proposed framework, the retinal vasculature segmentation and the ICP registration, was applied to a secondary set of scans obtained from a light damage model. A qualitative assessment of the registration showed no registration failures.

  14. Substantia Nigra Free Water Increases Longitudinally in Parkinson Disease.

    Science.gov (United States)

    Guttuso, T; Bergsland, N; Hagemeier, J; Lichter, D G; Pasternak, O; Zivadinov, R

    2018-02-01

    Free water in the posterior substantia nigra obtained from a bi-tensor diffusion MR imaging model has been shown to significantly increase over 1- and 4-year periods in patients with early-stage idiopathic Parkinson disease compared with healthy controls, which suggests that posterior substantia nigra free water may be an idiopathic Parkinson disease progression biomarker. Due to the known temporal posterior-to-anterior substantia nigra degeneration in idiopathic Parkinson disease, we assessed longitudinal changes in free water in both the posterior and anterior substantia nigra in patients with later-stage idiopathic Parkinson disease and age-matched healthy controls for comparison. Nineteen subjects with idiopathic Parkinson disease and 19 age-matched healthy control subjects were assessed on the same 3T MR imaging scanner at baseline and after approximately 3 years. Baseline mean idiopathic Parkinson disease duration was 7.1 years. Both anterior and posterior substantia nigra free water showed significant intergroup differences at baseline ( P Parkinson disease versus healthy controls); however, only anterior substantia nigra free water showed significant longitudinal group × time interaction increases ( P = .021, idiopathic Parkinson disease versus healthy controls). There were no significant longitudinal group × time interaction differences found for conventional diffusion tensor imaging or free water-corrected DTI assessments in either the anterior or posterior substantia nigra. Results from this study provide further evidence supporting substantia nigra free water as a promising disease-progression biomarker in idiopathic Parkinson disease that may help to identify disease-modifying therapies if used in future clinical trials. Our novel finding of longitudinal increases in anterior but not posterior substantia nigra free water is potentially a result of the much longer disease duration of our cohort compared with previously studied cohorts and the known

  15. Within-subject template estimation for unbiased longitudinal image analysis.

    Science.gov (United States)

    Reuter, Martin; Schmansky, Nicholas J; Rosas, H Diana; Fischl, Bruce

    2012-07-16

    Longitudinal image analysis has become increasingly important in clinical studies of normal aging and neurodegenerative disorders. Furthermore, there is a growing appreciation of the potential utility of longitudinally acquired structural images and reliable image processing to evaluate disease modifying therapies. Challenges have been related to the variability that is inherent in the available cross-sectional processing tools, to the introduction of bias in longitudinal processing and to potential over-regularization. In this paper we introduce a novel longitudinal image processing framework, based on unbiased, robust, within-subject template creation, for automatic surface reconstruction and segmentation of brain MRI of arbitrarily many time points. We demonstrate that it is essential to treat all input images exactly the same as removing only interpolation asymmetries is not sufficient to remove processing bias. We successfully reduce variability and avoid over-regularization by initializing the processing in each time point with common information from the subject template. The presented results show a significant increase in precision and discrimination power while preserving the ability to detect large anatomical deviations; as such they hold great potential in clinical applications, e.g. allowing for smaller sample sizes or shorter trials to establish disease specific biomarkers or to quantify drug effects. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Thyrotropin levels are associated with chronic kidney disease among healthy subjects in cross-sectional analysis of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

    Science.gov (United States)

    Peixoto de Miranda, Érique José F; Bittencourt, Márcio Sommer; Goulart, Alessandra C; Santos, Itamar S; de Oliveira Titan, Silvia Maria; Ladeira, Roberto Marini; Barreto, Sandhi Maria; Lotufo, Paulo A; Benseñor, Isabela Judith Martins

    2017-12-01

    Few studies have evaluated a possible relationship between thyrotropin levels and glomerular filtration rate (GFR) and albumin/creatinine ratio in euthyroid subjects. We aimed to analyze this association using baseline data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Cross-sectionally, we included subjects with normal thyroid function and with subclinical hypothyroidism (SCH). We excluded individuals using medications that affect thyroid function. Linear and logistic regression models evaluated GFR estimated by Chronic Kidney Disease Epidemiology Collaboration (CKD-Epi) and albuminuria/creatinine ratio as dependent variables and thyrotropin quartiles in individuals with euthyroidism and SCH as independent variables, adjusted for demographical characteristics and diseases related to CKD. We included 13,193 subjects with a median age of 51 years [interquartile range, (IQR): 45-58], 6840 (51.8%) women, 12,416 (94.1%) euthyroid, and 777 (5.9%) with SCH. SCH subjects were characterized by higher age, triglycerides, frequency of white race, cardiovascular disease, CKD, and former smokers. In adjusted models, log-transformed TSH in euthyroid subjects was inversely and strongly associated with CKD (β = -2.181, 95% CI -2.714 to -1.648), P < 0.0001 for glomerular filtration rate and 4.528 (1.190-7.865) for albuminuria/creatinine ratio. Multivariate logistic models for euthyroid subjects showed an OR of 1.45 (95% CI 1.15-1.83) for GFR and of 1.95 (95% CI 1.08-3.54) for albuminuria/creatinine ratio in the fourth quartile of TSH using the first as the reference. Thyrotropin levels are independently associated with CKD in euthyroid subjects.

  17. Shapes related to longitudinal studies of disease

    DEFF Research Database (Denmark)

    Erleben, Lene Lillemark

    investigated four different proximity markers which lead to significantly improved marker values between NC and AD after correction for whole brain and hippocampus volume. Based on the different proximity markers we have chosen the surface connectivity marker that gave the best separation to investigate......This dissertation investigates novel markers for cardiovascular diseases (CVD) and Alzheimer's disease (AD). Both CVD and AD are among the large diseases counted in morbidity and mortality in the western world, which makes them huge and increasing problems. By investigating and learning....... The first part of this dissertation studies the growth patterns of atherosclerotic calcified deposits in the lumbar aorta based on x-ray images over an 8-year time period. We have been able to find simple growth patterns that explain how the calcifications evolve. The calcifications grew on average 41 % (p...

  18. Big data in Parkinson's disease: using smartphones to remotely detect longitudinal disease phenotypes.

    Science.gov (United States)

    Prince, John; Arora, Siddharth; de Vos, Maarten

    2018-04-26

    To better understand the longitudinal characteristics of Parkinson's disease (PD) through the analysis of finger tapping and memory tests collected remotely using smartphones. Using a large cohort (312 PD subjects and 236 controls) of participants in the mPower study, we extract clinically validated features from a finger tapping and memory test to monitor the longitudinal behaviour of study participants. We investigate any discrepancy in learning rates associated with motor and non-motor tasks between PD subjects and healthy controls. The ability of these features to predict self-assigned severity measures is assessed whilst simultaneously inspecting the severity scoring system for floor-ceiling effects. Finally, we study the relationship between motor and non-motor longitudinal behaviour to determine if separate aspects of the disease are dependent on one another. We find that the test performances of the most severe subjects show significant correlations with self-assigned severity measures. Interestingly, less severe subjects do not show significant correlations, which is shown to be a consequence of floor-ceiling effects within the mPower self-reporting severity system. We find that motor performance after practise is a better predictor of severity than baseline performance suggesting that starting performance at a new motor task is less representative of disease severity than the performance after the test has been learnt. We find PD subjects show significant impairments in motor ability as assessed through the alternating finger tapping (AFT) test in both the short- and long-term analyses. In the AFT and memory tests we demonstrate that PD subjects show a larger degree of longitudinal performance variability in addition to requiring more instances of a test to reach a steady state performance than healthy subjects. Our findings pave the way forward for objective assessment and quantification of longitudinal learning rates in PD. This can be particularly

  19. Persistence and clearance of Ebola virus RNA from seminal fluid of Ebola virus disease survivors: a longitudinal analysis and modelling study

    Directory of Open Access Journals (Sweden)

    Daouda Sissoko, MD

    2017-01-01

    Full Text Available Summary: Background: By January, 2016, all known transmission chains of the Ebola virus disease (EVD outbreak in west Africa had been stopped. However, there is concern about persistence of Ebola virus in the reproductive tract of men who have survived EVD. We aimed to use biostatistical modelling to describe the dynamics of Ebola virus RNA load in seminal fluid, including clearance parameters. Methods: In this longitudinal study, we recruited men who had been discharged from three Ebola treatment units in Guinea between January and July, 2015. Participants provided samples of seminal fluid at follow-up every 3–6 weeks, which we tested for Ebola virus RNA using quantitative real-time RT-PCR. Representative specimens from eight participants were then inoculated into immunodeficient mice to test for infectivity. We used a linear mixed-effect model to analyse the dynamics of virus persistence in seminal fluid over time. Findings: We enrolled 26 participants and tested 130 seminal fluid specimens; median follow up was 197 days (IQR 187–209 days after enrolment, which corresponded to 255 days (228–287 after disease onset. Ebola virus RNA was detected in 86 semen specimens from 19 (73% participants. Median duration of Ebola virus RNA detection was 158 days after onset (73–181; maximum 407 days at end of follow-up. Mathematical modelling of the quantitative time-series data showed a mean clearance rate of Ebola virus RNA from seminal fluid of −0·58 log units per month, although the clearance kinetic varied greatly between participants. Using our biostatistical model, we predict that 50% and 90% of male survivors clear Ebola virus RNA from seminal fluid at 115 days (90% prediction interval 72–160 and 294 days (212–399 after disease onset, respectively. We also predicted that the number of men positive for Ebola virus RNA in affected countries would decrease from about 50 in January 2016, to fewer than 1 person by July, 2016. Infectious

  20. Longitudinal analysis of quality of life, clinical, radiographic, echocardiographic, and laboratory variables in dogs with myxomatous mitral valve disease receiving pimobendan or benazepril: the QUEST study.

    Science.gov (United States)

    Häggström, J; Boswood, A; O'Grady, M; Jöns, O; Smith, S; Swift, S; Borgarelli, M; Gavaghan, B; Kresken, J-G; Patteson, M; Åblad, B; Bussadori, C M; Glaus, T; Kovačević, A; Rapp, M; Santilli, R A; Tidholm, A; Eriksson, A; Belanger, M C; Deinert, M; Little, C J L; Kvart, C; French, A; Rønn-Landbo, M; Wess, G; Eggertsdottir, A; Lynne O'Sullivan, M; Schneider, M; Lombard, C W; Dukes-McEwan, J; Willis, R; Louvet, A; DiFruscia, R

    2013-01-01

    Myxomatous mitral valve disease (MMVD) is an important cause of morbidity and mortality in dogs. To compare, throughout the period of follow-up of dogs that had not yet reached the primary endpoint, the longitudinal effects of pimobendan versus benazepril hydrochloride treatment on quality-of-life (QoL) variables, concomitant congestive heart failure (CHF) treatment, and other outcome variables in dogs suffering from CHF secondary to MMVD. A total of 260 dogs in CHF because of MMVD. A prospective single-blinded study with dogs randomized to receive pimobendan (0.4-0.6 mg/kg/day) or benazepril hydrochloride (0.25-1.0 mg/kg/day). Differences in outcome variables and time to intensification of CHF treatment were compared. A total of 124 dogs were randomized to pimobendan and 128 to benazepril. No difference was found between groups in QoL variables during the trial. Time from inclusion to 1st intensification of CHF treatment was longer in the pimobendan group (pimobendan 98 days, IQR 30-276 days versus benazepril 59 days, IQR 11-121 days; P = .0005). Postinclusion, dogs in the pimobendan group had smaller heart size based on VHS score (P = .013) and left ventricular diastolic (P = .035) and systolic (P = .0044) dimensions, higher body temperature (P = .030), serum sodium (P = .0027), and total protein (P = .0003) concentrations, and packed cell volume (P = .030). Incidence of arrhythmias was similar in treatment groups. Pimobendan versus benazepril resulted in similar QoL during the study, but conferred increased time before intensification of CHF treatment. Pimobendan treatment resulted in smaller heart size, higher body temperature, and less retention of free water. Copyright © 2013 by the American College of Veterinary Internal Medicine.

  1. Longitudinal decline in speech production in Parkinson's disease spectrum disorders.

    Science.gov (United States)

    Ash, Sharon; Jester, Charles; York, Collin; Kofman, Olga L; Langey, Rachel; Halpin, Amy; Firn, Kim; Dominguez Perez, Sophia; Chahine, Lama; Spindler, Meredith; Dahodwala, Nabila; Irwin, David J; McMillan, Corey; Weintraub, Daniel; Grossman, Murray

    2017-08-01

    We examined narrative speech production longitudinally in non-demented (n=15) and mildly demented (n=8) patients with Parkinson's disease spectrum disorder (PDSD), and we related increasing impairment to structural brain changes in specific language and motor regions. Patients provided semi-structured speech samples, describing a standardized picture at two time points (mean±SD interval=38±24months). The recorded speech samples were analyzed for fluency, grammar, and informativeness. PDSD patients with dementia exhibited significant decline in their speech, unrelated to changes in overall cognitive or motor functioning. Regression analysis in a subset of patients with MRI scans (n=11) revealed that impaired language performance at Time 2 was associated with reduced gray matter (GM) volume at Time 1 in regions of interest important for language functioning but not with reduced GM volume in motor brain areas. These results dissociate language and motor systems and highlight the importance of non-motor brain regions for declining language in PDSD. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Persistence and clearance of Ebola virus RNA from seminal fluid of Ebola virus disease survivors: a longitudinal analysis and modelling study.

    Science.gov (United States)

    Sissoko, Daouda; Duraffour, Sophie; Kerber, Romy; Kolie, Jacques Seraphin; Beavogui, Abdoul Habib; Camara, Alseny-Modet; Colin, Géraldine; Rieger, Toni; Oestereich, Lisa; Pályi, Bernadett; Wurr, Stephanie; Guedj, Jeremie; Nguyen, Thi Huyen Tram; Eggo, Rosalind M; Watson, Conall H; Edmunds, W John; Bore, Joseph Akoi; Koundouno, Fara Raymond; Cabeza-Cabrerizo, Mar; Carter, Lisa L; Kafetzopoulou, Liana Eleni; Kuisma, Eeva; Michel, Janine; Patrono, Livia Victoria; Rickett, Natasha Y; Singethan, Katrin; Rudolf, Martin; Lander, Angelika; Pallasch, Elisa; Bockholt, Sabrina; Rodríguez, Estefanía; Di Caro, Antonino; Wölfel, Roman; Gabriel, Martin; Gurry, Céline; Formenty, Pierre; Keïta, Sakoba; Malvy, Denis; Carroll, Miles W; Anglaret, Xavier; Günther, Stephan

    2017-01-01

    By January, 2016, all known transmission chains of the Ebola virus disease (EVD) outbreak in west Africa had been stopped. However, there is concern about persistence of Ebola virus in the reproductive tract of men who have survived EVD. We aimed to use biostatistical modelling to describe the dynamics of Ebola virus RNA load in seminal fluid, including clearance parameters. In this longitudinal study, we recruited men who had been discharged from three Ebola treatment units in Guinea between January and July, 2015. Participants provided samples of seminal fluid at follow-up every 3-6 weeks, which we tested for Ebola virus RNA using quantitative real-time RT-PCR. Representative specimens from eight participants were then inoculated into immunodeficient mice to test for infectivity. We used a linear mixed-effect model to analyse the dynamics of virus persistence in seminal fluid over time. We enrolled 26 participants and tested 130 seminal fluid specimens; median follow up was 197 days (IQR 187-209 days) after enrolment, which corresponded to 255 days (228-287) after disease onset. Ebola virus RNA was detected in 86 semen specimens from 19 (73%) participants. Median duration of Ebola virus RNA detection was 158 days after onset (73-181; maximum 407 days at end of follow-up). Mathematical modelling of the quantitative time-series data showed a mean clearance rate of Ebola virus RNA from seminal fluid of -0·58 log units per month, although the clearance kinetic varied greatly between participants. Using our biostatistical model, we predict that 50% and 90% of male survivors clear Ebola virus RNA from seminal fluid at 115 days (90% prediction interval 72-160) and 294 days (212-399) after disease onset, respectively. We also predicted that the number of men positive for Ebola virus RNA in affected countries would decrease from about 50 in January 2016, to fewer than 1 person by July, 2016. Infectious virus was detected in 15 of 26 (58%) specimens tested in mice. Time

  3. Dynamics of the connectome in Huntington's disease: A longitudinal diffusion MRI study

    OpenAIRE

    Odish, Omar F.F.; Caeyenberghs, Karen; Hosseini, Hadi; van den Bogaard, Simon J.A.; Roos, Raymund A.C.; Leemans, Alexander

    2015-01-01

    Abstract Objectives To longitudinally investigate the connectome in different stages of Huntington's disease (HD) by applying graph theoretical analysis to diffusion MRI data. Experimental design We constructed weighted structural networks and calculated their topological properties. Twenty-two premanifest (preHD), 10 early manifest HD and 24 healthy controls completed baseline and 2 year follow-up scans. We stratified the preHD group based on their predicted years to disease onset into a far...

  4. Delirium superimposed on dementia: defining disease states and course from longitudinal measurements of a multivariate index using latent class analysis and hidden Markov chains.

    Science.gov (United States)

    Ciampi, Antonio; Dyachenko, Alina; Cole, Martin; McCusker, Jane

    2011-12-01

    The study of mental disorders in the elderly presents substantial challenges due to population heterogeneity, coexistence of different mental disorders, and diagnostic uncertainty. While reliable tools have been developed to collect relevant data, new approaches to study design and analysis are needed. We focus on a new analytic approach. Our framework is based on latent class analysis and hidden Markov chains. From repeated measurements of a multivariate disease index, we extract the notion of underlying state of a patient at a time point. The course of the disorder is then a sequence of transitions among states. States and transitions are not observable; however, the probability of being in a state at a time point, and the transition probabilities from one state to another over time can be estimated. Data from 444 patients with and without diagnosis of delirium and dementia were available from a previous study. The Delirium Index was measured at diagnosis, and at 2 and 6 months from diagnosis. Four latent classes were identified: fairly healthy, moderately ill, clearly sick, and very sick. Dementia and delirium could not be separated on the basis of these data alone. Indeed, as the probability of delirium increased, so did the probability of decline of mental functions. Eight most probable courses were identified, including good and poor stable courses, and courses exhibiting various patterns of improvement. Latent class analysis and hidden Markov chains offer a promising tool for studying mental disorders in the elderly. Its use may show its full potential as new data become available.

  5. Longitudinal data analysis a handbook of modern statistical methods

    CERN Document Server

    Fitzmaurice, Garrett; Verbeke, Geert; Molenberghs, Geert

    2008-01-01

    Although many books currently available describe statistical models and methods for analyzing longitudinal data, they do not highlight connections between various research threads in the statistical literature. Responding to this void, Longitudinal Data Analysis provides a clear, comprehensive, and unified overview of state-of-the-art theory and applications. It also focuses on the assorted challenges that arise in analyzing longitudinal data. After discussing historical aspects, leading researchers explore four broad themes: parametric modeling, nonparametric and semiparametric methods, joint

  6. Analysis of critically refracted longitudinal waves

    Energy Technology Data Exchange (ETDEWEB)

    Pei, Ning, E-mail: npei@iastate.edu; Bond, Leonard J., E-mail: npei@iastate.edu [Center for Nondestructive Evaluation, Iowa State University, Ames, IA 50011 (United States)

    2015-03-31

    Fabrication processes, such as, welding, forging, and rolling can induce residual stresses in metals that will impact product performance and phenomena such as cracking and corrosion. To better manage residual stress tools are needed to map their distribution. The critically refracted ultrasonic longitudinal (LCR) wave is one such approach that has been used for residual stress characterization. It has been shown to be sensitive to stress and less sensitive to the effects of the texture of the material. Although the LCR wave is increasingly widely applied, the factors that influence the formation of the LCR beam are seldom discussed. This paper reports a numerical model used to investigate the transducers' parameters that can contribute to the directionality of the LCR wave and hence enable performance optimization when used for industrial applications. An orthogonal test method is used to study the transducer parameters which influence the LCR wave beams. This method provides a design tool that can be used to study and optimize multiple parameter experiments and it can identify which parameter or parameters are of most significance. The simulation of the sound field in a 2-D 'water-steel' model is obtained using a Spatial Fourier Analysis method. The effects of incident angle, standoff, the aperture and the center frequency of the transducer were studied. Results show that the aperture of the transducer, the center frequency and the incident angle are the most important factors in controlling the directivity of the resulting LCR wave fields.

  7. Longitudinal evaluation of bronchopulmonary disease in children with cystic fibrosis.

    Science.gov (United States)

    Farrell, Philip M; Li, Zhanhai; Kosorok, Michael R; Laxova, Anita; Green, Christopher G; Collins, Jannette; Lai, Hui-Chuan; Makholm, Linda M; Rock, Michael J; Splaingard, Mark L

    2003-09-01

    Children with cystic fibrosis (CF) develop bronchopulmonary disease at variable ages. Determining the epidemiology of chronic lung disease and quantifying its severity, however, have been difficult in infants and young children. As part of the Wisconsin CF Neonatal Screening Project, we were presented with an ideal opportunity to assess longitudinally the evolution of symptoms, signs, and quantitative measures of CF respiratory disease. After newborn screening test results led to early recognition, 64 patients diagnosed at a median age of 6.71 weeks were enrolled and studied systematically at a median age of 11.3 years to obtain clinical information, chest radiographs, and pulmonary function tests. Our observations revealed that a frequent cough by history is evident by 10.5 months of age in half the patients. Quantitative chest radiology (CXR scoring) demonstrated that potentially irreversible abnormalities are present in half the children by 2 years. The severity of Wisconsin and Brasfield CXR scores increased in association with respiratory infections. Longitudinal progression of Wisconsin CXR scores was related to age (P < 0.001), pancreatic insufficiency (P = 0.005), and respiratory secretion cultures positive for Staphylococus aureas (P = 0.039). In contrast, serial spirometry showed limited sensitivity, as did lung volume determinations; neither was satisfactory as repeated measures with acceptable quality control until after 7 years of age. Time to event analyses revealed that half the patients had % predicted FEF(25-75) and FEV(1)/FVC values greater than 80% until 10.7 and 9.9 years, respectively. We conclude that of the methods evaluated, quantitative chest radiology is currently the best procedure for frequent assessment of bronchopulmonary disease in CF, and that radiographic progression is evident in approximately 85% of patients by 5 years of age. Our results also suggest that bronchiectasis and other radiographic evidence of chronic infection are

  8. Transverse versus Longitudinal Incisions for Femoral Artery Exposure in Treating Patients with Peripheral Vascular Disease.

    Science.gov (United States)

    Parikh, Punam P; Rubio, Gustavo A; Patel, Kunal; Gupta, Kapil; Jones, Keith; Rey, Jorge; Robinson, Handel

    2018-02-01

    This study evaluates differences in wound complication rate when transverse versus longitudinal incision is utilized to expose femoral vessels in managing patients with peripheral vascular disease. A retrospective review from 2013 to 2015 was conducted of 150 patients undergoing 156 lower extremity revascularizations with femoral artery exposure through a groin incision. Patients were stratified into 2 groups, transverse versus longitudinal groin incision. Data were reviewed for 3 surgeons that utilize either transverse or longitudinal groin incision in patients undergoing common or iliofemoral endarterectomies, or where femoral artery was used as inflow and/or outflow vessel for limb revascularization. Each group had a comparative outcomes analysis based on incision type. The primary outcome was wound complication, defined as any wound infection, lymphocele, hematoma, dehiscence, pseudoaneurysm, or necrosis. Other outcomes studied included unplanned return to operating room for wound complication, wound vacuum therapy, and soft-tissue flap closure. Data were analyzed using 2-tailed chi-squared test and Student's t-test. Patients in the transverse (n = 85 cases) versus longitudinal (n = 71 cases) cohorts were similar in relation to demographics and comorbidities. Overall mean follow-up was 220 days. Patients with a transverse as compared to longitudinal incision had a significantly lower overall wound complication rate, 7% vs. 42%, respectively (P transverse incisions were associated with lower incidence of unplanned return to the operating room to manage wound complications than patients with a longitudinal incision (5% vs. 23%, respectively; P Transverse versus longitudinal incisions were also associated with significantly lower need for wound vacuum therapy (6% vs. 15%, respectively; P Transverse groin incisions for femoral artery exposure may offer a lower risk of wound complications for open procedures as compared to a longitudinal incision

  9. Statin use in adults at high risk of cardiovascular disease mortality: cross-sectional analysis of baseline data from The Irish Longitudinal Study on Ageing (TILDA).

    LENUS (Irish Health Repository)

    Murphy, Catriona

    2015-07-01

    This study aims to examine the extent to which statins are used by adults at high risk of cardiovascular disease (CVD) compared to European clinical guidelines. The high-risk groups examined are those with (1) known CVD, (2) known diabetes and (3) a high or very high risk (≥5%) of CVD mortality based on Systematic COronary Risk Evaluation (SCORE).

  10. The Role of Microsimulation in Longitudinal Data Analysis

    Directory of Open Access Journals (Sweden)

    Douglas A. Wolf

    2001-12-01

    microsimulation also has the potential to contribute to longitudinal data analysis in several ways, including extending the range of outputs generated by a model, addressing several defective-data problems, and serving as a vehicle for missing-data imputation. This paper discusses microsimulation procedures suitable for several commonly-used statistical models applied to longitudinal data. It also addresses the unique role that can be played by microsimulation in longitudinal data analysis, and the problem of accounting for the several sources of variability associated with microsimulation procedures.

  11. The longitudinal impact of depression on disability in Parkinson disease.

    Science.gov (United States)

    Pontone, Gregory M; Bakker, Catherine C; Chen, Shaojie; Mari, Zoltan; Marsh, Laura; Rabins, Peter V; Williams, James R; Bassett, Susan S

    2016-05-01

    Depression in Parkinson disease (PD) is a common problem that worsens quality of life and causes disability. However, little is known about the longitudinal impact of depression on disability in PD. This study examined the association between disability and DSM-IV-TR depression status across six years. Longitudinal cohort study with assessments at study entry, year two, four, and six conducted in the Morris K. Udall Parkinson Disease Research Center. Recruitment totaled 137 adult men and women with idiopathic PD in which up to six years of data on demographic, motor, and non-motor variables was collected. Movement disorder specialists used the structured interview for DSM-IV-TR depressive disorders and the Northwestern Disability Scale to assess depression and disability. A generalized linear mixed model was fitted with Northwestern Disability Scale score as the dependent variable to determine the effect of baseline depression status on disability. A total of 43 participants were depressed at baseline compared to 94 without depression. Depressed participants were more likely to be female, were less educated, were less likely to take dopamine agonists, and more likely to have motor fluctuations. Controlling for these variables, symptomatic depression predicted greater disability compared to both never depressed (p = 0.0133) and remitted depression (p = 0.0009). Disability associated with symptomatic depression at baseline was greater over the entire six-year period compared to participants with remitted depressive episodes or who were never depressed. Persisting depression is associated with a long-term adverse impact on daily functioning in PD. Adequate treatment or spontaneous remission of depression improves ADL function. Copyright © 2015 John Wiley & Sons, Ltd.

  12. Multivariate longitudinal data analysis with mixed effects hidden Markov models.

    Science.gov (United States)

    Raffa, Jesse D; Dubin, Joel A

    2015-09-01

    Multiple longitudinal responses are often collected as a means to capture relevant features of the true outcome of interest, which is often hidden and not directly measurable. We outline an approach which models these multivariate longitudinal responses as generated from a hidden disease process. We propose a class of models which uses a hidden Markov model with separate but correlated random effects between multiple longitudinal responses. This approach was motivated by a smoking cessation clinical trial, where a bivariate longitudinal response involving both a continuous and a binomial response was collected for each participant to monitor smoking behavior. A Bayesian method using Markov chain Monte Carlo is used. Comparison of separate univariate response models to the bivariate response models was undertaken. Our methods are demonstrated on the smoking cessation clinical trial dataset, and properties of our approach are examined through extensive simulation studies. © 2015, The International Biometric Society.

  13. Causal mediation analysis for longitudinal data with exogenous exposure

    OpenAIRE

    Bind, M.-A. C.; Vanderweele, T. J.; Coull, B. A.; Schwartz, J. D.

    2015-01-01

    Mediation analysis is a valuable approach to examine pathways in epidemiological research. Prospective cohort studies are often conducted to study biological mechanisms and often collect longitudinal measurements on each participant. Mediation formulae for longitudinal data have been developed. Here, we formalize the natural direct and indirect effects using a causal framework with potential outcomes that allows for an interaction between the exposure and the mediator. To allow different type...

  14. Cross-Sectional Analysis of Longitudinal Mediation Processes.

    Science.gov (United States)

    O'Laughlin, Kristine D; Martin, Monica J; Ferrer, Emilio

    2018-01-01

    Statistical mediation analysis can help to identify and explain the mechanisms behind psychological processes. Examining a set of variables for mediation effects is a ubiquitous process in the social sciences literature; however, despite evidence suggesting that cross-sectional data can misrepresent the mediation of longitudinal processes, cross-sectional analyses continue to be used in this manner. Alternative longitudinal mediation models, including those rooted in a structural equation modeling framework (cross-lagged panel, latent growth curve, and latent difference score models) are currently available and may provide a better representation of mediation processes for longitudinal data. The purpose of this paper is twofold: first, we provide a comparison of cross-sectional and longitudinal mediation models; second, we advocate using models to evaluate mediation effects that capture the temporal sequence of the process under study. Two separate empirical examples are presented to illustrate differences in the conclusions drawn from cross-sectional and longitudinal mediation analyses. Findings from these examples yielded substantial differences in interpretations between the cross-sectional and longitudinal mediation models considered here. Based on these observations, researchers should use caution when attempting to use cross-sectional data in place of longitudinal data for mediation analyses.

  15. Longitudinal decline of driving safety in Parkinson disease.

    Science.gov (United States)

    Uc, Ergun Y; Rizzo, Matthew; O'Shea, Amy M J; Anderson, Steven W; Dawson, Jeffrey D

    2017-11-07

    To longitudinally assess and predict on-road driving safety in Parkinson disease (PD). Drivers with PD (n = 67) and healthy controls (n = 110) drove a standardized route in an instrumented vehicle and were invited to return 2 years later. A professional driving expert reviewed drive data and videos to score safety errors. At baseline, drivers with PD performed worse on visual, cognitive, and motor tests, and committed more road safety errors compared to controls (median PD 38.0 vs controls 30.5; p < 0.001). A smaller proportion of drivers with PD returned for repeat testing (42.8% vs 62.7%; p < 0.01). At baseline, returnees with PD made fewer errors than nonreturnees with PD (median 34.5 vs 40.0; p < 0.05) and performed similar to control returnees (median 33). Baseline global cognitive performance of returnees with PD was better than that of nonreturnees with PD, but worse than for control returnees ( p < 0.05). After 2 years, returnees with PD showed greater cognitive decline and larger increase in error counts than control returnees (median increase PD 13.5 vs controls 3.0; p < 0.001). Driving error count increase in the returnees with PD was predicted by greater error count and worse visual acuity at baseline, and by greater interval worsening of global cognition, Unified Parkinson's Disease Rating Scale activities of daily living score, executive functions, visual processing speed, and attention. Despite drop out of the more impaired drivers within the PD cohort, returning drivers with PD, who drove like controls without PD at baseline, showed many more driving safety errors than controls after 2 years. Driving decline in PD was predicted by baseline driving performance and deterioration of cognitive, visual, and functional abnormalities on follow-up. © 2017 American Academy of Neurology.

  16. Regression analysis of sparse asynchronous longitudinal data.

    Science.gov (United States)

    Cao, Hongyuan; Zeng, Donglin; Fine, Jason P

    2015-09-01

    We consider estimation of regression models for sparse asynchronous longitudinal observations, where time-dependent responses and covariates are observed intermittently within subjects. Unlike with synchronous data, where the response and covariates are observed at the same time point, with asynchronous data, the observation times are mismatched. Simple kernel-weighted estimating equations are proposed for generalized linear models with either time invariant or time-dependent coefficients under smoothness assumptions for the covariate processes which are similar to those for synchronous data. For models with either time invariant or time-dependent coefficients, the estimators are consistent and asymptotically normal but converge at slower rates than those achieved with synchronous data. Simulation studies evidence that the methods perform well with realistic sample sizes and may be superior to a naive application of methods for synchronous data based on an ad hoc last value carried forward approach. The practical utility of the methods is illustrated on data from a study on human immunodeficiency virus.

  17. A longitudinal analysis of nursing home outcomes.

    Science.gov (United States)

    Porell, F; Caro, F G; Silva, A; Monane, M

    1998-10-01

    To investigate resident and facility attributes associated with long-term care health outcomes in nursing homes. Quarterly Management Minutes Questionnaire (MMQ) survey data for Medicaid case-mix reimbursement of nursing homes in Massachusetts from 1991 to 1994, for specification of outcomes and resident attributes. Facility attributes are specified from cost report data. Multivariate logistic and "state-dependence" regression models are estimated for survival, ADL functional status, incontinence status, and mental status outcomes from longitudinal residence histories of Medicaid residents spanning 3 to 36 months in length. Outcomes are specified to be a function of resident demographic and diagnostic attributes and facility-level operating and nurse staffing attributes. The estimated parameters for resident demographic and diagnostic attributes showed a great deal of construct validity with respect to clinical expectations regarding risk factors for adverse outcomes. Few facility attributes were associated with outcomes generally, and none was significantly associated with all four outcomes. The absence of uniform associations between facility attributes and the various long-term care health outcomes studied suggests that strong facility performance on one health outcome may coexist with much weaker performance on other outcomes. This has implications for the aggregation of individual facility performance measures on multiple outcomes and the development of overall outcome performance measures.

  18. Longitudinal changes in microstructural white matter metrics in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Chantel D. Mayo

    2017-01-01

    Conclusion: The current results indicate that sensitivity to white matter microstructure is a promising avenue for AD biomarker research. Additional longitudinal studies on both white and grey matter are warranted to further evaluate potential clinical utility.

  19. Sensitivity Analysis of Mixed Models for Incomplete Longitudinal Data

    Science.gov (United States)

    Xu, Shu; Blozis, Shelley A.

    2011-01-01

    Mixed models are used for the analysis of data measured over time to study population-level change and individual differences in change characteristics. Linear and nonlinear functions may be used to describe a longitudinal response, individuals need not be observed at the same time points, and missing data, assumed to be missing at random (MAR),…

  20. Longitudinal Jitter Analysis of a Linear Accelerator Electron Gun

    Directory of Open Access Journals (Sweden)

    MingShan Liu

    2016-11-01

    Full Text Available We present measurements and analysis of the longitudinal timing jitter of a Beijing Electron Positron Collider (BEPCII linear accelerator electron gun. We simulated the longitudinal jitter effect of the gun using PARMELA to evaluate beam performance, including: beam profile, average energy, energy spread, and XY emittances. The maximum percentage difference of the beam parameters is calculated to be 100%, 13.27%, 42.24% and 65.01%, 86.81%, respectively. Due to this, the bunching efficiency is reduced to 54%. However, the longitudinal phase difference of the reference particle was 9.89°. The simulation results are in agreement with tests and are helpful to optimize the beam parameters by tuning the trigger timing of the gun during the bunching process.

  1. A Systematic Review of Longitudinal Studies Which Measure Alzheimer's Disease Biomarkers.

    Science.gov (United States)

    Lawrence, Emma; Vegvari, Carolin; Ower, Alison; Hadjichrysanthou, Christoforos; De Wolf, Frank; Anderson, Roy M

    2017-01-01

    Alzheimer's disease (AD) is a progressive and fatal neurodegenerative disease, with no effective treatment or cure. A gold standard therapy would be treatment to slow or halt disease progression; however, knowledge of causation in the early stages of AD is very limited. In order to determine effective endpoints for possible therapies, a number of quantitative surrogate markers of disease progression have been suggested, including biochemical and imaging biomarkers. The dynamics of these various surrogate markers over time, particularly in relation to disease development, are, however, not well characterized. We reviewed the literature for studies that measured cerebrospinal fluid or plasma amyloid-β and tau, or took magnetic resonance image or fluorodeoxyglucose/Pittsburgh compound B-positron electron tomography scans, in longitudinal cohort studies. We summarized the properties of the major cohort studies in various countries, commonly used diagnosis methods and study designs. We have concluded that additional studies with repeat measures over time in a representative population cohort are needed to address the gap in knowledge of AD progression. Based on our analysis, we suggest directions in which research could move in order to advance our understanding of this complex disease, including repeat biomarker measurements, standardization and increased sample sizes.

  2. Longitudinal muscle of the esophagus: its role in esophageal health and disease.

    Science.gov (United States)

    Mittal, Ravinder K

    2013-07-01

    The muscularis propria of the esophagus is organized into circular and longitudinal muscle layers. The function of the longitudinal muscle and its role in bolus propulsion are not clear. The goal of this review is to summarize what is known of the role of the longitudinal muscle in health, as well as in sensory and motor disorders of the esophagus. Simultaneous manometry and ultrasound imaging reveal that, during peristalsis, the two muscle layers of the esophagus contract in perfect synchrony. On the contrary, during transient lower esophageal sphincter (LES) relaxation, longitudinal muscle contracts independent of the circular muscle. Recent studies have provided novel insights into the role of the longitudinal muscle in LES relaxation and descending relaxation of the esophagus. In certain diseases (e.g. some motility disorders of the esophagus), there is discoordination between the two muscle layers, which likely plays an important role in the genesis of dysphagia and delayed esophageal emptying. There is close temporal correlation between prolonged contractions of the longitudinal muscles of the esophagus and esophageal 'angina-like' pain. Novel techniques to record longitudinal muscle contraction are reviewed. Longitudinal muscles of the esophagus play a key role in the physiology and pathophysiology of esophageal sensory and motor function. Neuro-pharmacologic controls of circular and longitudinal muscle are different, which provides an opportunity for the development of novel pharmacological therapies in the treatment of esophageal sensory and motor disorders.

  3. Reliability of the Alzheimer's disease assessment scale (ADAS-Cog) in longitudinal studies.

    Science.gov (United States)

    Khan, Anzalee; Yavorsky, Christian; DiClemente, Guillermo; Opler, Mark; Liechti, Stacy; Rothman, Brian; Jovic, Sofija

    2013-11-01

    Considering the scarcity of longitudinal assessments of reliability, there is need for a more precise understanding of cognitive decline in Alzheimer's Disease (AD). The primary goal was to assess longitudinal changes in inter-rater reliability, test retest reliability and internal consistency of scores of the ADAS-Cog. 2,618 AD subjects were enrolled in seven randomized, double-blind, placebo-controlled, multicenter-trials from 1986 to 2009. Reliability, internal-consistency and cross-sectional analysis of ADAS-Cog and MMSE across seven visits were examined. Intra-class correlation (ICC) for ADAS-Cog was moderate to high supporting their reliability. Absolute Agreement ICCs 0.392 (Visit-7) to 0.806 (Visit-2) showed a progressive decrease in correlations across time. Item analysis revealed a decrease in item correlations, with the lowest correlations for Visit 7 for Commands (ICC=0.148), Comprehension (ICC=0.092), Spoken Language (ICC=0.044). Suitable assessment of AD treatments is maintained through accurate measurement of clinically significant outcomes. Targeted rater education ADAS-Cog items over-time can improve ability to administer and score the scale.

  4. An overview of longitudinal data analysis methods for neurological research.

    Science.gov (United States)

    Locascio, Joseph J; Atri, Alireza

    2011-01-01

    The purpose of this article is to provide a concise, broad and readily accessible overview of longitudinal data analysis methods, aimed to be a practical guide for clinical investigators in neurology. In general, we advise that older, traditional methods, including (1) simple regression of the dependent variable on a time measure, (2) analyzing a single summary subject level number that indexes changes for each subject and (3) a general linear model approach with a fixed-subject effect, should be reserved for quick, simple or preliminary analyses. We advocate the general use of mixed-random and fixed-effect regression models for analyses of most longitudinal clinical studies. Under restrictive situations or to provide validation, we recommend: (1) repeated-measure analysis of covariance (ANCOVA), (2) ANCOVA for two time points, (3) generalized estimating equations and (4) latent growth curve/structural equation models.

  5. An Overview of Longitudinal Data Analysis Methods for Neurological Research

    Directory of Open Access Journals (Sweden)

    Joseph J. Locascio

    2011-10-01

    Full Text Available The purpose of this article is to provide a concise, broad and readily accessible overview of longitudinal data analysis methods, aimed to be a practical guide for clinical investigators in neurology. In general, we advise that older, traditional methods, including (1 simple regression of the dependent variable on a time measure, (2 analyzing a single summary subject level number that indexes changes for each subject and (3 a general linear model approach with a fixed-subject effect, should be reserved for quick, simple or preliminary analyses. We advocate the general use of mixed-random and fixed-effect regression models for analyses of most longitudinal clinical studies. Under restrictive situations or to provide validation, we recommend: (1 repeated-measure analysis of covariance (ANCOVA, (2 ANCOVA for two time points, (3 generalized estimating equations and (4 latent growth curve/structural equation models.

  6. An Overview of Longitudinal Data Analysis Methods for Neurological Research

    OpenAIRE

    Locascio, Joseph J.; Atri, Alireza

    2011-01-01

    The purpose of this article is to provide a concise, broad and readily accessible overview of longitudinal data analysis methods, aimed to be a practical guide for clinical investigators in neurology. In general, we advise that older, traditional methods, including (1) simple regression of the dependent variable on a time measure, (2) analyzing a single summary subject level number that indexes changes for each subject and (3) a general linear model approach with a fixed-subject effect, shoul...

  7. Sample size determination for mediation analysis of longitudinal data.

    Science.gov (United States)

    Pan, Haitao; Liu, Suyu; Miao, Danmin; Yuan, Ying

    2018-03-27

    Sample size planning for longitudinal data is crucial when designing mediation studies because sufficient statistical power is not only required in grant applications and peer-reviewed publications, but is essential to reliable research results. However, sample size determination is not straightforward for mediation analysis of longitudinal design. To facilitate planning the sample size for longitudinal mediation studies with a multilevel mediation model, this article provides the sample size required to achieve 80% power by simulations under various sizes of the mediation effect, within-subject correlations and numbers of repeated measures. The sample size calculation is based on three commonly used mediation tests: Sobel's method, distribution of product method and the bootstrap method. Among the three methods of testing the mediation effects, Sobel's method required the largest sample size to achieve 80% power. Bootstrapping and the distribution of the product method performed similarly and were more powerful than Sobel's method, as reflected by the relatively smaller sample sizes. For all three methods, the sample size required to achieve 80% power depended on the value of the ICC (i.e., within-subject correlation). A larger value of ICC typically required a larger sample size to achieve 80% power. Simulation results also illustrated the advantage of the longitudinal study design. The sample size tables for most encountered scenarios in practice have also been published for convenient use. Extensive simulations study showed that the distribution of the product method and bootstrapping method have superior performance to the Sobel's method, but the product method was recommended to use in practice in terms of less computation time load compared to the bootstrapping method. A R package has been developed for the product method of sample size determination in mediation longitudinal study design.

  8. A Longitudinal Motor Characterisation of the HdhQ111 Mouse Model of Huntington's Disease.

    Science.gov (United States)

    Yhnell, Emma; Dunnett, Stephen B; Brooks, Simon P

    2016-05-31

    Huntington's disease (HD) is a rare, incurable neurodegenerative disorder caused by a CAG trinucleotide expansion with the first exon of the huntingtin gene. Numerous knock-in mouse models are currently available for modelling HD. However, before their use in scientific research, these models must be characterised to determine their face and predictive validity as models of the disease and their reliability in recapitulating HD symptoms. Manifest HD is currently diagnosed upon the onset of motor symptoms, thus we sought to longitudinally characterise the progression and severity of motor signs in the HdhQ111 knock-in mouse model of HD, in heterozygous mice. An extensive battery of motor tests including: rotarod, inverted lid test, balance beam, spontaneous locomotor activity and gait analysis were applied longitudinally to a cohort of HdhQ111 heterozygous mice in order to progressively assess motor function. A progressive failure to gain body weight was demonstrated from 11 months of age and motor problems in all measures of balance beam performance were shown in HdhQ111 heterozygous animals in comparison to wild type control animals from 9 months of age. A decreased latency to fall from the rotarod was demonstrated in HdhQ111 heterozygous animals in comparison to wild type animals, although this was not progressive with time. No genotype specific differences were demonstrated in any of the other motor tests included in the test battery. The HdhQ111 heterozygous mouse demonstrates a subtle and progressive motor phenotype that begins at 9 months of age. This mouse model represents an early disease stage and would be ideal for testing therapeutic strategies that require elongated lead-in times, such as viral gene therapies or striatal transplantation.

  9. Macular function and morphologic features in juvenile stargardt disease: longitudinal study.

    Science.gov (United States)

    Testa, Francesco; Melillo, Paolo; Di Iorio, Valentina; Orrico, Ada; Attanasio, Marcella; Rossi, Settimio; Simonelli, Francesca

    2014-12-01

    To evaluate disease progression in a cohort of patients with a clinical and genetic diagnosis of Stargardt disease. Longitudinal cohort study. A total of 56 selected patients with a clinical and molecular diagnosis of Stargardt disease, an early age of onset, and a median follow-up length of 2 years. Patients underwent routine examination, including full-field electroretinography, microperimetry, and optical coherence tomography. Best-corrected visual acuity (BCVA), mean retinal sensitivity, fixation stability, preferred retinal locus, inner segment/outer segment (IS/OS) junction loss, and atrophic lesion area. A total of 56 patients with a mean age at disease onset of 15.3 years (range, 3-28 years), a mean disease duration of 12.1 years, and a mean age at baseline of 27.4 years were analyzed. The median BCVA was 20/200 in both eyes. Optical coherence tomography parameters (IS/OS alteration and retinal pigment epithelium lesion area) were obtained in only 49 patients because the signal quality was poor in the remaining 7 patients. Optical coherence tomography revealed a mean retinal pigment epithelium lesion area of 2.6 mm(2), preserved foveal IS/OS in 4.1% of patients, loss of foveal IS/OS in 59.2% of patients, and extensive loss of macular IS/OS in 36.7% of patients. Microperimetric findings showed a reduced macular sensitivity (mean, 10 decibels [dB]) and an unstable fixation in half of the patient cohort. The longitudinal analysis showed a significant progressive reduction of BCVA and macular sensitivity (at an estimated rate of 0.04 decimals and 1.19 dB/year, respectively) associated with a significant enlargement of retinal pigment epithelium lesion area (0.282 mm(2)/year). No significant changes in ophthalmoscopic findings and electroretinographic responses were detected. This study highlights the importance of microperimetry and optical coherence tomography in monitoring patients with Stargardt disease. Quantifying the decline of visual functionality and

  10. Macular function and morphological features in juvenile Stargardt disease: Longitudinal study

    Science.gov (United States)

    Testa, Francesco; Melillo, Paolo; Iorio, Valentina Di; Orrico, Ada; Attanasio, Marcella; Rossi, Settimio; Simonelli, Francesca

    2014-01-01

    Purpose to evaluate disease progression in a cohort of patients with clinical and genetic diagnosis of Stargardt disease. Design longitudinal cohort study. Subjects 56 selected patients with a clinical and molecular diagnosis of Stargardt disease, an early age of onset and a median follow-up length of two years. Methods patients underwent routine examination including full-field electroretinography, microperimetry and optical coherence tomography. Main Outcome Measures best corrected visual acuity, mean retinal sensitivity, fixation stability, preferred retinal locus, inner-outer segment (IS/OS) junction loss, atrophic lesion area. Results 56 patients with a mean age of disease onset of 15.3 years (range: 3 - 28 years), a mean disease length of 12.1 years and a mean age at baseline of 27.4 years were analyzed. The median best corrected visual acuity was 20/200 in both eyes. Optical coherence tomography parameters (IS/OS alteration and retinal pigment epithelium lesion area) were obtained in 49 patients because signal quality was poor in the remaining 7 patients. Optical coherence tomography revealed a mean retinal pigment epithelium lesion area of 2.6 mm2, preserved foveal IS/OS in 4.1% of patients, loss of foveal IS/OS in 59.2%, and extensive loss of macular IS/OS in 36.7%. Microperimetric findings showed a reduced macular sensitivity (mean 10 dB) and an unstable fixation in half of the patient cohort. The longitudinal analysis showed a significant progressive reduction of best corrected visual acuity and macular sensitivity (at an estimated rate of 0.04 decimals and 1.19 dB per year, respectively) associated with a significant enlargement of retinal pigment epithelium lesion area (0.282 mm2 per year). No significant changes in ophthalmoscopic findings and electroretinographic responses were detected. Conclusions this study highlights the importance of microperimetry and optical coherence tomography in monitoring Stargardt patients. In fact, quantifying the

  11. MR image analysis: Longitudinal cardiac motion influences left ventricular measurements

    International Nuclear Information System (INIS)

    Berkovic, Patrick; Hemmink, Maarten; Parizel, Paul M.; Vrints, Christiaan J.; Paelinck, Bernard P.

    2010-01-01

    Background: Software for the analysis of left ventricular (LV) volumes and mass using border detection in short-axis images only, is hampered by through-plane cardiac motion. Therefore we aimed to evaluate software that involves longitudinal cardiac motion. Methods: Twenty-three consecutive patients underwent 1.5-Tesla cine magnetic resonance (MR) imaging of the entire heart in the long-axis and short-axis orientation with breath-hold steady-state free precession imaging. Offline analysis was performed using software that uses short-axis images (Medis MASS) and software that includes two-chamber and four-chamber images to involve longitudinal LV expansion and shortening (CAAS-MRV). Intraobserver and interobserver reproducibility was assessed by using Bland-Altman analysis. Results: Compared with MASS software, CAAS-MRV resulted in significantly smaller end-diastolic (156 ± 48 ml versus 167 ± 52 ml, p = 0.001) and end-systolic LV volumes (79 ± 48 ml versus 94 ± 52 ml, p < 0.001). In addition, CAAS-MRV resulted in higher LV ejection fraction (52 ± 14% versus 46 ± 13%, p < 0.001) and calculated LV mass (154 ± 52 g versus 142 ± 52 g, p = 0.004). Intraobserver and interobserver limits of agreement were similar for both methods. Conclusion: MR analysis of LV volumes and mass involving long-axis LV motion is a highly reproducible method, resulting in smaller LV volumes, higher ejection fraction and calculated LV mass.

  12. The association between mood and anxiety disorders, and coronary heart disease in Brazil: A cross-sectional analysis on the Brazilian longitudinal study of adult health (ELSA-Brasil

    Directory of Open Access Journals (Sweden)

    Andrew eKemp

    2015-02-01

    Full Text Available Background: Associations between major depressive disorder and coronary heart disease (CHD have been established, and these associations increase risk of future morbidity and mortality. Prior research has been carried out in high-income countries. Here we examine associations between the mood and anxiety disorders, and coronary heart disease in a large cohort at baseline from Brazil, a country facing a variety of challenges that may affect these associations.Methods: Participants included 15,105 civil servants aged 35 to 74 at baseline (2008-10 from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil. CHD (N=721 included self-reported angina pectoris (n=305, myocardial infarction (MI (n=259 and coronary revascularization (n=239. Hierarchical logistic regression analyses were conducted to estimate odds ratios and confidence intervals. Results: Major findings indicate that comorbid major depressive disorder and anxiety disorders (n=434 are associated with a 3-fold increase in CHD, major depressive disorder alone (n=170 with a 2-fold increase in CHD, while generalised anxiety disorder alone (n=1,394 and mixed anxiety and depression disorder (MADD; n=1,844 – symptoms present, but diagnostic threshold not reached – are associated with a 1.5-fold increase in CHD, after full adjustment for covariates. Conclusions: The association with CHD is greatest in those with psychiatric comorbidity, while associations were also observed in major depressive disorder and generalised anxiety disorder without comorbidity. While findings are limited by the cross-sectional design of the study, given the known risks associated with comorbidity of the mood and anxiety disorders with CHD, findings reinforce the importance of comprehensive health assessment in Brazil.

  13. Epigenetic variability in conversion to psychosis: novel findings from an innovative longitudinal methylomic analysis.

    Science.gov (United States)

    Kebir, Oussama; Chaumette, Boris; Krebs, Marie-Odile

    2018-04-26

    Conversion to psychosis is a longitudinal process during which several epigenetic changes have been described. We tested the hypothesis that epigenetic variability in the methylomes of ultra-high risk (UHR) individuals may contribute to the risk of conversion. We studied a longitudinal cohort of UHR individuals (n = 39) and compared two groups (converters, n = 14 vs. non-converters, n = 25). A longitudinal methylomic study was conducted using Infinium HumanMethylation450 BeadChip covering half a million cytosine-phosphate-guanine (CpG) sites across the human genome from whole-blood samples. We used two statistical methods to investigate the variability of methylation probes. (i) The search for longitudinal variable methylation probes (VMPs) based on median comparisons identified two VMPs in converters only. The first CpG was located in the MACROD2 gene and the second CpG was in an intergenic region at 8q24.21. (ii) The detection of outliers using variance analysis related to private epimutations identified a dozen CpGs in converters only and highlighted two genes (RAC1 and SPHK1) from the sphingolipid signaling pathway. Our study is the first to support increased methylome variability during conversion to psychosis. We speculate that stochastic factors could increase DNA methylation variability and have a role in the complex pathophysiology of conversion to psychosis as well as in other psychiatric diseases.

  14. Longitudinal Andhra Pradesh Eye Disease Study: rationale, study design and research methodology.

    Science.gov (United States)

    Khanna, Rohit C; Murthy, Gudlavalleti Vs; Marmamula, Srinivas; Mettla, Asha Latha; Giridhar, Pyda; Banerjee, Seema; Shekhar, Konegari; Chakrabarti, Subhabrata; Gilbert, Clare; Rao, Gullapalli N

    2016-03-01

    The rationale, objectives, study design and procedures for the longitudinal Andhra Pradesh Eye Disease Study are described. A longitudinal cohort study was carried out. Participants include surviving cohort from the rural component of Andhra Pradesh Eye Disease Study. During 1996-2000, Andhra Pradesh Eye Disease Survey was conducted in three rural (n = 7771) and one urban (n = 2522) areas (now called Andhra Pradesh Eye Disease Study 1). In 2009-2010, a feasibility exercise (Andhra Pradesh Eye Disease Study 2) for a longitudinal study (Andhra Pradesh Eye Disease Study 3) was undertaken in the rural clusters only, as urban clusters no longer existed. In Andhra Pradesh Eye Disease Study 3, a detailed interview will be carried out to collect data on sociodemographic factors, ocular and systemic history, risk factors, visual function, knowledge of eye diseases and barriers to accessing services. All participants will also undergo a comprehensive eye examination including photography of lens, optic disc and retina, Optic Coherence Tomography of the posterior segment, anthropometry, blood pressure and frailty measures. Measures include estimates of the incidence of visual impairment and age-related eye disease (lens opacities, glaucoma and age-related macular degeneration) and the progression of eye disease (lens opacities and myopia) and associated risk factors. Of the 7771 respondents examined in rural areas in Andhra Pradesh Eye Disease Study 1, 5447 (70.1%) participants were traced in Andhra Pradesh Eye Disease Study 2. These participants will be re-examined. Andhra Pradesh Eye Disease Study 3 will provide data on the incidence and progression of visual impairment and major eye diseases and their associated risk factors in India. The study will provide further evidence to aid planning eye care services. © 2015 Royal Australian and New Zealand College of Ophthalmologists.

  15. Analysis on Longitudinal Dose according to Change of Field Width

    International Nuclear Information System (INIS)

    Jung, Won Seok; Shin, Ryung Mi; Oh, Byung Cheon; Jo, Jun Young; Kim, Gi Chul; Choi, Tae Gu; Back, Jong Geal

    2011-01-01

    To analyze the accuracy of tumor volume dose following field width change, to check the difference of dose change by using self-made moving car, and to evaluate practical delivery tumor dose when tomotherapy in the treatment of organ influenced by breathing. By using self-made moving car, the difference of longitudinal movement (0.0 cm, 1.0 cm, 1.5 cm, 2.0 cm) was applied and compared calculated dose with measured dose according to change of field width (1.05 cm, 2.50 cm, 5.02 cm) and apprehended margin of error. Then done comparative analysis in degree of photosensitivity of DQA film measured by using Gafchromic EBT film. Dose profile and Gamma histogram were used to measure degree of photosensitivity of DQA film. When field width were 1.05 cm, 2.50 cm, 5.02 cm, margin of error of dose delivery coefficient was -2.00%, -0.39%, -2.55%. In dose profile of Gafchromic EBT film's analysis, the movement of moving car had greater motion toward longitudinal direction and as field width was narrower, big error increased considerably at high dose part compared to calculated dose. The more field width was narrowed, gamma index had a large considerable influence of moving at gamma histogram. We could check the difference of longitudinal dose of moving organ. In order to small field width and minimize organ moving due to breathing, it is thought to be needed to develop breathing control unit and fixation tool.

  16. Multilevel predictors of adolescent physical activity: a longitudinal analysis

    Directory of Open Access Journals (Sweden)

    Hearst Mary O

    2012-02-01

    Full Text Available Abstract Background To examine how factors from a social ecologic model predict physical activity (PA among adolescents using a longitudinal analysis. Methods Participants in this longitudinal study were adolescents (ages 10-16 at baseline and one parent enrolled in the Transdisciplinary Research on Energetics and Cancer-Identifying Determinants of Eating and Activity (TREC-IDEA and the Etiology of Childhood Obesity (ECHO. Both studies were designed to assess a socio-ecologic model of adolescent obesity risk. PA was collected using ActiGraph activity monitors at two time points 24 months apart. Other measures included objective height and weight, adolescent and parent questionnaires on multilevel psychological, behavioral and social determinants of PA, and a home PA equipment inventory. Analysis was conducted using SAS, including descriptive characteristics, bivariate and stepped multivariate mixed models, using baseline adjustment. Models were stratified by gender. Results There were 578 adolescents with complete data. Results suggest few statistically significant longitudinal associations with physical activity measured as minutes of MVPA or total counts from accelerometers. For boys, greater self-efficacy (B = 0.75, p = 0.01 and baseline MVPA (B = 0.55, p p = 0.01 and barriers (B = -0.32, p = 0.05 significantly predicted MVPA at follow-up in the full model. The full multilevel model explained 30% of the variance in PA among boys and 24% among girls. Conclusions PA change in adolescents is a complex issue that is not easily understood. Our findings suggest early PA habits are the most important predictor of PA levels in adolescence. Intervention may be necessary prior to middle school to maintain PA through adolescence.

  17. Diverging longitudinal changes in astrocytosis and amyloid PET in autosomal dominant Alzheimer's disease.

    Science.gov (United States)

    Rodriguez-Vieitez, Elena; Saint-Aubert, Laure; Carter, Stephen F; Almkvist, Ove; Farid, Karim; Schöll, Michael; Chiotis, Konstantinos; Thordardottir, Steinunn; Graff, Caroline; Wall, Anders; Långström, Bengt; Nordberg, Agneta

    2016-03-01

    Alzheimer's disease is a multifactorial dementia disorder characterized by early amyloid-β, tau deposition, glial activation and neurodegeneration, where the interrelationships between the different pathophysiological events are not yet well characterized. In this study, longitudinal multitracer positron emission tomography imaging of individuals with autosomal dominant or sporadic Alzheimer's disease was used to quantify the changes in regional distribution of brain astrocytosis (tracer (11)C-deuterium-L-deprenyl), fibrillar amyloid-β plaque deposition ((11)C-Pittsburgh compound B), and glucose metabolism ((18)F-fluorodeoxyglucose) from early presymptomatic stages over an extended period to clinical symptoms. The 52 baseline participants comprised autosomal dominant Alzheimer's disease mutation carriers (n = 11; 49.6 ± 10.3 years old) and non-carriers (n = 16; 51.1 ± 14.2 years old; 10 male), and patients with sporadic mild cognitive impairment (n = 17; 61.9 ± 6.4 years old; nine male) and sporadic Alzheimer's disease (n = 8; 63.0 ± 6.5 years old; five male); for confidentiality reasons, the gender of mutation carriers is not revealed. The autosomal dominant Alzheimer's disease participants belonged to families with known mutations in either presenilin 1 (PSEN1) or amyloid precursor protein (APPswe or APParc) genes. Sporadic mild cognitive impairment patients were further divided into (11)C-Pittsburgh compound B-positive (n = 13; 62.0 ± 6.4; seven male) and (11)C-Pittsburgh compound B-negative (n = 4; 61.8 ± 7.5 years old; two male) groups using a neocortical standardized uptake value ratio cut-off value of 1.41, which was calculated with respect to the cerebellar grey matter. All baseline participants underwent multitracer positron emission tomography scans, cerebrospinal fluid biomarker analysis and neuropsychological assessment. Twenty-six of the participants underwent clinical and imaging follow-up examinations after 2.8 ± 0.6 years. By using linear

  18. A Longitudinal Study on Resting State Functional Connectivity in Behavioral Variant Frontotemporal Dementia and Alzheimer's Disease.

    Science.gov (United States)

    Hafkemeijer, Anne; Möller, Christiane; Dopper, Elise G P; Jiskoot, Lize C; van den Berg-Huysmans, Annette A; van Swieten, John C; van der Flier, Wiesje M; Vrenken, Hugo; Pijnenburg, Yolande A L; Barkhof, Frederik; Scheltens, Philip; van der Grond, Jeroen; Rombouts, Serge A R B

    2017-01-01

    Alzheimer's disease (AD) and behavioral variant frontotemporal dementia (bvFTD) are the most common types of early-onset dementia. We applied longitudinal resting state functional magnetic resonance imaging (fMRI) to delineate functional brain connections relevant for disease progression and diagnostic accuracy. We used two-center resting state fMRI data of 20 AD patients (65.1±8.0 years), 12 bvFTD patients (64.7±5.4 years), and 22 control subjects (63.8±5.0 years) at baseline and 1.8-year follow-up. We used whole-network and voxel-based network-to-region analyses to study group differences in functional connectivity at baseline and follow-up, and longitudinal changes in connectivity within and between groups. At baseline, connectivity between paracingulate gyrus and executive control network, between cuneal cortex and medial visual network, and between paracingulate gyrus and salience network was higher in AD compared with controls. These differences were also present after 1.8 years. At follow-up, connectivity between angular gyrus and right frontoparietal network, and between paracingulate gyrus and default mode network was lower in bvFTD compared with controls, and lower compared with AD between anterior cingulate gyrus and executive control network, and between lateral occipital cortex and medial visual network. Over time, connectivity decreased in AD between precuneus and right frontoparietal network and in bvFTD between inferior frontal gyrus and left frontoparietal network. Longitudinal changes in connectivity between supramarginal gyrus and right frontoparietal network differ between both patient groups and controls. We found disease-specific brain regions with longitudinal connectivity changes. This suggests the potential of longitudinal resting state fMRI to delineate regions relevant for disease progression and for diagnostic accuracy, although no group differences in longitudinal changes in the direct comparison of AD and bvFTD were found.

  19. Causal mediation analysis for longitudinal data with exogenous exposure.

    Science.gov (United States)

    Bind, M-A C; Vanderweele, T J; Coull, B A; Schwartz, J D

    2016-01-01

    Mediation analysis is a valuable approach to examine pathways in epidemiological research. Prospective cohort studies are often conducted to study biological mechanisms and often collect longitudinal measurements on each participant. Mediation formulae for longitudinal data have been developed. Here, we formalize the natural direct and indirect effects using a causal framework with potential outcomes that allows for an interaction between the exposure and the mediator. To allow different types of longitudinal measures of the mediator and outcome, we assume two generalized mixed-effects models for both the mediator and the outcome. The model for the mediator has subject-specific random intercepts and random exposure slopes for each cluster, and the outcome model has random intercepts and random slopes for the exposure, the mediator, and their interaction. We also expand our approach to settings with multiple mediators and derive the mediated effects, jointly through all mediators. Our method requires the absence of time-varying confounding with respect to the exposure and the mediator. This assumption is achieved in settings with exogenous exposure and mediator, especially when exposure and mediator are not affected by variables measured at earlier time points. We apply the methodology to data from the Normative Aging Study and estimate the direct and indirect effects, via DNA methylation, of air pollution, and temperature on intercellular adhesion molecule 1 (ICAM-1) protein levels. Our results suggest that air pollution and temperature have a direct effect on ICAM-1 protein levels (i.e. not through a change in ICAM-1 DNA methylation) and that temperature has an indirect effect via a change in ICAM-1 DNA methylation. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. A longitudinal assessment of periodontal disease in 52 Miniature Schnauzers.

    Science.gov (United States)

    Marshall, Mark D; Wallis, Corrin V; Milella, Lisa; Colyer, Alison; Tweedie, Andrew D; Harris, Stephen

    2014-09-01

    Periodontal disease (PD) is the most widespread oral disease in dogs and has been associated with serious systemic diseases. The disease is more prevalent in small breeds compared to large breeds and incidence increases with advancing age. In prevalence studies 84% of Beagles over the age of 3 and 100% of Poodles over the age of 4 were diagnosed with PD. Current knowledge of the rate of progression of PD is limited. The objective of this study was to determine the rate of PD progression in Miniature Schnauzers, an at risk small breed of dog. Dogs (n = 52, age 1.3-6.9 years) who had received a regular oral care regime prior to this study were assessed for levels of gingivitis and periodontitis around the whole gingival margin in every tooth under general anaesthetic. Assessments were conducted approximately every six weeks for up to 60 weeks following the cessation of the oral care regime. All of the 2155 teeth assessed entered the study with some level of gingivitis. 23 teeth entered the study with periodontitis, observed across 12 dogs aged between 1.3 and 6.9 years. 35 dogs had at least 12 teeth progress to periodontitis within 60 weeks. Of the teeth that progressed to periodontitis, 54% were incisors. The lingual aspect of the incisors was significantly more likely to be affected (p periodontitis-affected teeth was variable with 24% of the aspects affected having very mild gingivitis, 36% mild gingivitis and 40% moderate gingivitis. Periodontitis progression rate was significantly faster in older dogs. Only one dog (age 3.5) did not have any teeth progress to periodontitis after 60 weeks. This is the first study to have assessed the progression rate of periodontitis in Miniature Schnauzers and highlights that with no oral care regime, the early stages of periodontitis develop rapidly in this breed. An oral care regime and twice yearly veterinary dental health checks should be provided from an early age for this breed and other breeds with similar

  1. Determinants of exercise among children. II. A longitudinal analysis.

    Science.gov (United States)

    DiLorenzo, T M; Stucky-Ropp, R C; Vander Wal, J S; Gotham, H J

    1998-01-01

    Research has demonstrated that physical activity serves an important preventive function against the development of cardiovascular disease. The recognition that U.S. children are often sedentary, coupled with the observation that physical activity habits tend to persist into adulthood, has prompted the investigation of exercise determinants consistent with social learning theory. The purposes of the present study were to identify social learning variables relevant to children's exercise and to explore the longitudinal predictive value of the determinants. Data were collected from 111 families (N = 54 girls, N = 57 boys) who were interviewed in both Phase 1 (fifth and sixth grades) and Phase 2 (eight and ninth grades) of this study. Data from mothers (N = 111) were collected during both phases; data from 80 fathers were collected at Phase 2 only. The results of simultaneous stepwise regression analyses indicated that child's enjoyment of physical activity was the only consistent predictor of physical activity during Phase 1. At Phase 2, child's exercise knowledge, mother's physical activity, and child's and mother's friend modeling/support emerged as predictors for girls. For boys, child's self-efficacy for physical activity, exercise knowledge, parental modeling, and interest in sports media were important. Longitudinally, mother's self-efficacy, barriers to exercise, enjoyment of physical activity, and child's self-efficacy for physical activity were important for girls. Only child's exercise knowledge predicted boys' physical activity. The addition of information from fathers nearly doubled the explanatory power of the predictors for both genders. Socialization in the family unit exerts a tremendous influence on health-related behaviors such as exercise. The relative importance of determinants seems to differ for girls and boys and the pattern of these determinants appears to change over time.

  2. Heart and skeletal muscle inflammation (HSMI disease diagnosed on a British Columbia salmon farm through a longitudinal farm study.

    Directory of Open Access Journals (Sweden)

    Emiliano Di Cicco

    Full Text Available Heart and skeletal muscle inflammation (HSMI is an emerging disease of marine-farmed Atlantic Salmon (Salmo salar, first recognized in 1999 in Norway, and later also reported in Scotland and Chile. We undertook a longitudinal study involving health evaluation over an entire marine production cycle on one salmon farm in British Columbia (Canada. In previous production cycles at this farm site and others in the vicinity, cardiac lesions not linked to a specific infectious agent or disease were identified. Histologic assessments of both live and moribund fish samples collected at the farm during the longitudinal study documented at the population level the development, peak, and recovery phases of HSMI. The fish underwent histopathological evaluation of all tissues, Twort's Gram staining, immunohistochemistry, and molecular quantification in heart tissue of 44 agents known or suspected to cause disease in salmon. Our analysis showed evidence of HSMI histopathological lesions over an 11-month timespan, with the prevalence of lesions peaking at 80-100% in sampled fish, despite mild clinical signs with no associated elevation in mortalities reported at the farm level. Diffuse mononuclear inflammation and myodegeneration, consistent with HSMI, was the predominant histologic observation in affected heart and skeletal muscle. Infective agent monitoring identified three agents at high prevalence in salmon heart tissue, including Piscine orthoreovirus (PRV, and parasites Paranucleospora theridion and Kudoa thyrsites. However, PRV alone was statistically correlated with the occurrence and severity of histopathological lesions in the heart. Immunohistochemical staining further localized PRV throughout HSMI development, with the virus found mainly within red blood cells in early cases, moving into the cardiomyocytes within or, more often, on the periphery of the inflammatory reaction during the peak disease, and reducing to low or undetectable levels later in

  3. Overview of national attitudes toward nuclear energy: a longitudinal analysis

    International Nuclear Information System (INIS)

    Rankin, W.L.

    1982-01-01

    The purpose of this paper is to present a longitudinal overview of public attitudes toward nuclear power development in the United States. Over ten years of attitudinal data are now available for analysis of the stability of such attitudes over time. These data are useful to many people, including policy makers in government, nuclear industry decision makers, and public action groups that support and oppose nuclear power. This information is also useful in checking the claims of those who purport to be speaking for the public. The level of public acceptance for nuclear power in the near term and into the next century can only be estimated at this time. But this estimate can be based on nearly a decade of survey research

  4. Analysis of longitudinal data from animals with missing values using SPSS.

    Science.gov (United States)

    Duricki, Denise A; Soleman, Sara; Moon, Lawrence D F

    2016-06-01

    Testing of therapies for disease or injury often involves the analysis of longitudinal data from animals. Modern analytical methods have advantages over conventional methods (particularly when some data are missing), yet they are not used widely by preclinical researchers. Here we provide an easy-to-use protocol for the analysis of longitudinal data from animals, and we present a click-by-click guide for performing suitable analyses using the statistical package IBM SPSS Statistics software (SPSS). We guide readers through the analysis of a real-life data set obtained when testing a therapy for brain injury (stroke) in elderly rats. If a few data points are missing, as in this example data set (for example, because of animal dropout), repeated-measures analysis of covariance may fail to detect a treatment effect. An alternative analysis method, such as the use of linear models (with various covariance structures), and analysis using restricted maximum likelihood estimation (to include all available data) can be used to better detect treatment effects. This protocol takes 2 h to carry out.

  5. Longitudinal patterns of semantic and episodic memory in frontotemporal lobar degeneration and Alzheimer's disease.

    Science.gov (United States)

    Xie, Sharon X; Libon, David J; Wang, Xingmei; Massimo, Lauren; Moore, Peachie; Vesely, Luisa; Khan, Alea; Chatterjee, Anjan; Coslett, H Branch; Hurtig, Howard I; Liang, Tsao-Wei; Grossman, Murray

    2010-03-01

    The longitudinal assessment of episodic and semantic memory was obtained from 236 patients diagnosed with Alzheimer's disease (AD, n = 128) and with frontotemporal lobar degeneration (FTLD, n = 108), including patients with a social comportment/dysexecutive (SOC/EXEC) disorder, progressive nonfluent aphasia (PNFA), semantic dementia (SemD), and corticobasal syndrome (CBS). At the initial assessment, AD patients obtained a lower score on the delayed free recall test than other patients. Longitudinal analyses for delayed free recall found converging performance, with all patients reaching the same level of impairment as AD patients. On the initial evaluation for delayed recognition, AD patients also obtained lower scores than other groups. Longitudinal analyses for delayed recognition test performance found that AD patients consistently produced lower scores than other groups and no convergence between AD and other dementia groups was seen. For semantic memory, there were no initial between-group differences. However, longitudinal analyses for semantic memory revealed group differences over illness duration, with worse performance for SemD versus AD, PNFA, SOC/EXEC, and CBS patients. These data suggest the presence of specific longitudinal patterns of impairment for episodic and semantic memory in AD and FTLD patients suggesting that all forms of dementia do not necessarily converge into a single phenotype.

  6. The longitudinal relationship between mental health disorders and chronic disease for older adults: a population-based study.

    Science.gov (United States)

    Chen, Chun-Min; Lee, I-Chen; Su, Yung-Yu; Mullan, Judy; Chiu, Herng-Chia

    2017-09-01

    Although mental health disorders in older adults are common, their relationship with chronic disease and the influence of chronic disease on the development of mental health disorders over time is not well understood. This longitudinal study investigated the change in status of mental health disorders and chronic disease, as well as their interrelationships, over time. Participants included community-dwelling older adults living in Taiwan, aged 65 years or older, who completed six waves of survey interviews. Mental health disorders were scored using the Short Psychiatric Evaluation Schedule, and chronic disease(s) status was recorded during consecutive biennial data collection waves. The autoregressive latent trajectory model and parallel latent growth curve model were used for data analysis. The study findings suggest that in older people pre-existing mental health disorders and/or chronic disease(s) will predispose them to developing significantly more mental health disorders and/or chronic diseases respectively. The study findings also suggest that pre-existing mental health disorders can significantly contribute to the development of chronic disease over time, and that pre-existing chronic disease(s) significantly can contribute to the development of mental health disorders over time, indicating a reciprocal interrelationship. Our study findings suggest that it in addition to monitoring and treating chronic disease(s) in older people, it is also important to monitor and treat their mental health disorders. Doing so will result in overall better health outcomes and will facilitate a better quality of life as they age. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  7. A Primer on Longitudinal Data Analysis in Education. Technical Report #1320

    Science.gov (United States)

    Nese, Joseph F. T.; Lai, Cheng-Fei; Anderson, Daniel

    2013-01-01

    Longitudinal data analysis in education is the study growth over time. A longitudinal study is one in which repeated observations of the same variables are recorded for the same individuals over a period of time. This type of research is known by many names (e.g., time series analysis or repeated measures design), each of which can imply subtle…

  8. Analysis of longitudinal data from animals where some data are missing in SPSS

    Science.gov (United States)

    Duricki, DA; Soleman, S; Moon, LDF

    2017-01-01

    Testing of therapies for disease or injury often involves analysis of longitudinal data from animals. Modern analytical methods have advantages over conventional methods (particularly where some data are missing) yet are not used widely by pre-clinical researchers. We provide here an easy to use protocol for analysing longitudinal data from animals and present a click-by-click guide for performing suitable analyses using the statistical package SPSS. We guide readers through analysis of a real-life data set obtained when testing a therapy for brain injury (stroke) in elderly rats. We show that repeated measures analysis of covariance failed to detect a treatment effect when a few data points were missing (due to animal drop-out) whereas analysis using an alternative method detected a beneficial effect of treatment; specifically, we demonstrate the superiority of linear models (with various covariance structures) analysed using Restricted Maximum Likelihood estimation (to include all available data). This protocol takes two hours to follow. PMID:27196723

  9. Patterns of longitudinal neural activity linked to different cognitive profiles in Parkinson’s disease

    Directory of Open Access Journals (Sweden)

    Atsuko Nagano-Saito

    2016-11-01

    Full Text Available Mild cognitive impairment in Parkinson’s disease (PD has been linked with functional brain changes. Previously, using functional magnetic resonance imaging (fMRI, we reported reduced cortico-striatal activity in patients with PD who also had mild cognitive impairment (MCI versus those who did not (non-MCI. We followed up these patients to investigate the longitudinal effect on the neural activity. Twenty-four non-demented patients with Parkinson’s disease (non-MCI: 12, MCI; 12 were included in the study. Each participant underwent two fMRIs while performing the Wisconsin Card Sorting Task 20 months apart. The non-MCI patients recruited the usual cognitive corticostriatal loop at the first and second sessions (Time 1 and Time 2, respectively. However, decreased activity was observed in the cerebellum and occipital area and increased activity was observed in the medial prefrontal cortex and parietal lobe during planning set-shift at Time 2. Increased activity in the precuneus was also demonstrated while executing set-shifts at Time 2. The MCI patients revealed more activity in the frontal, parietal and occipital lobes during planning set-shifts, and in the parietal and occipital lobes, precuneus, and cerebellum, during executing set-shift at Time 2. Analysis regrouping of both groups of PD patients revealed that hippocampal and thalamic activity at Time 1 was associated with less cognitive decline over time. Our results reveal that functional alteration along the time-points differed between the non-MCI and MCI patients. They also underline the importance of preserving thalamic and hippocampal function with respect to cognitive decline over time.

  10. A longitudinal analysis of nanotechnology literature: 1976-2004

    International Nuclear Information System (INIS)

    Li Xin; Chen Hsinchun; Dang Yan; Lin Yiling; Larson, Catherine A.; Roco, Mihail C.

    2008-01-01

    Nanotechnology research and applications have experienced rapid growth in recent years. We assessed the status of nanotechnology research worldwide by applying bibliographic, content map, and citation network analysis to a data set of about 200,000 nanotechnology papers published in the Thomson Science Citation Index Expanded database (SCI) from 1976 to 2004. This longitudinal study shows a quasi-exponential growth of nanotechnology articles with an average annual growth rate of 20.7% after 1991. The United States had the largest contribution of nanotechnology research and China and Korea had the fastest growth rates. The largest institutional contributions were from the Chinese Academy of Sciences and the Russian Academy of Sciences. The high-impact papers generally described tools, theories, technologies, perspectives, and overviews of nanotechnology. From the top 20 institutions, based on the average number of paper citations in 1976-2004, 17 were in the Unites States, 2 in France and 1 in Germany. Content map analysis identified the evolution of the major topics researched from 1976 to 2004, including investigative tools, physical phenomena, and experiment environments. Both the country citation network and the institution citation network had relatively high clustering, indicating the existence of citation communities in the two networks, and specific patterns in forming citation communities. The United States, Germany, Japan, and China were major citation centers in nanotechnology research with close inter-citation relationships.

  11. Digitomotography in Parkinson's disease: a cross-sectional and longitudinal study.

    Directory of Open Access Journals (Sweden)

    Walter Maetzler

    Full Text Available Motor symptoms in Parkinson's disease (PD are usually assessed with semi-quantitative tests such as the Unified PD Rating Scale (UPDRS which are limited by subjectivity, categorical design, and low sensitivity. Particularly bradykinesia as assessed e.g. with speeded index finger tapping exhibits low validity measures. This exploratory study set out to (i assess whether force transducer-based objective and quantitative analysis of motor coordination in index finger tapping is able to distinguish between PD patients and controls, and (ii assess longitudinal changes. Sixteen early-stage and 17 mid-stage PD patients as well as 18 controls were included in the cross-sectional part of the study; thirteen, 16 and 16 individuals of the respective groups agreed in a reassessment 12 months later. Frequency, force, rhythmicity, regularity and laterality of speeded and metronome paced tapping were recorded by digitomotography using a quantitative motor system ("Q-Motor". Analysis of cross-sectional data revealed most consistent differences between PD patients and controls in variability of tap performance across modalities assessed. Among PD patients, variability of taps and the ability to keep a given rhythm were associated with UPDRS motor and finger tapping scores. After 12 months, laterality parameters were reduced but no other parameters changed significantly. This data suggests that digitomotography provides quantitative and objective measures capable to differentiate PD from non-PD in a small cohort, however, the value of the assessment to track PD progression has to be further evaluated in larger cohorts of patients.

  12. Longitudinal multigroup invariance analysis of the satisfaction with food-related life scale in university students.

    Science.gov (United States)

    Schnettler, Berta; Miranda, Horacio; Miranda-Zapata, Edgardo; Salinas-Oñate, Natalia; Grunert, Klaus G; Lobos, Germán; Sepúlveda, José; Orellana, Ligia; Hueche, Clementina; Bonilla, Héctor

    2017-06-01

    This study examined longitudinal measurement invariance in the Satisfaction with Food-related Life (SWFL) scale using follow-up data from university students. We examined this measure of the SWFL in different groups of students, separated by various characteristics. Through non-probabilistic longitudinal sampling, 114 university students (65.8% female, mean age: 22.5) completed the SWFL questionnaire three times, over intervals of approximately one year. Confirmatory factor analysis was used to examine longitudinal measurement invariance. Two types of analysis were conducted: first, a longitudinal invariance by time, and second, a multigroup longitudinal invariance by sex, age, socio-economic status and place of residence during the study period. Results showed that the 3-item version of the SWFL exhibited strong longitudinal invariance (equal factor loadings and equal indicator intercepts). Longitudinal multigroup invariance analysis also showed that the 3-item version of the SWFL displays strong invariance by socio-economic status and place of residence during the study period over time. Nevertheless, it was only possible to demonstrate equivalence of the longitudinal factor structure among students of both sexes, and among those older and younger than 22 years. Generally, these findings suggest that the SWFL scale has satisfactory psychometric properties for longitudinal measurement invariance in university students with similar characteristics as the students that participated in this research. It is also possible to suggest that satisfaction with food-related life is associated with sex and age. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Retinal thickness as a marker of disease progression in longitudinal observation of patients with Wolfram syndrome.

    Science.gov (United States)

    Zmyslowska, Agnieszka; Fendler, Wojciech; Waszczykowska, Arleta; Niwald, Anna; Borowiec, Maciej; Jurowski, Piotr; Mlynarski, Wojciech

    2017-11-01

    Wolfram syndrome (WFS) is a recessively inherited monogenic form of diabetes coexisting with optic atrophy and neurodegenerative disorders with no currently recognized markers of disease progression. The aim of the study was to evaluate retinal parameters by using optical coherence tomography (OCT) in WFS patients after 2 years of follow-up and analysis of the parameters in relation to visual acuity. OCT parameters and visual acuity were measured in 12 WFS patients and 31 individuals with type 1 diabetes. Total thickness of the retinal nerve fiber layer (RNFL), average retinal thickness and total retinal volume decreased in comparison with previous OCT examination. Significant decreases were noted for RNFL (average difference -17.92 µm 95% CI -30.74 to -0.10; p = 0.0157), macular average thickness (average difference -5.38 µm 95% CI -10.63 to -2.36; p = 0.0067) and total retinal volume (average difference -0.15 mm 3 95% CI -0.30 to -0.07; p = 0.0070). Central thickness remained unchanged (average difference 1.5 µm 95% CI -7.61 to 10.61; p = 0.71). Visual acuity of WFS patients showed a strong negative correlation with diabetes duration (R = -0.82; p = 0.0010). After division of WFS patients into two groups (with low-vision and blind patients), all OCT parameters except for the RNFL value were lower in blind WFS patients. OCT measures structural parameters and can precede visual acuity loss. The OCT study in WFS patients should be performed longitudinally, and serial retinal examinations may be helpful as a potential end point for future clinical trials.

  14. Longitudinal multigroup invariance analysis of the satisfaction with food-related life scale in university students

    DEFF Research Database (Denmark)

    Schnettler, Berta; Miranda, Horacio; Miranda-Zapata, Edgardo

    2017-01-01

    This study examined longitudinal measurement invariance in the Satisfaction with Food-related Life (SWFL) scale using follow-up data from university students. We examined this measure of the SWFL in different groups of students, separated by various characteristics. Through non......-probabilistic longitudinal sampling, 114 university students (65.8% female, mean age: 22.5) completed the SWFL questionnaire three times, over intervals of approximately one year. Confirmatory factor analysis was used to examine longitudinal measurement invariance. Two types of analysis were conducted: first, a longitudinal...... students of both sexes, and among those older and younger than 22 years. Generally, these findings suggest that the SWFL scale has satisfactory psychometric properties for longitudinal measurement invariance in university students with similar characteristics as the students that participated...

  15. The traditional Japanese dietary pattern and longitudinal changes in cardiovascular disease risk factors in apparently healthy Japanese adults.

    Science.gov (United States)

    Niu, Kaijun; Momma, Haruki; Kobayashi, Yoritoshi; Guan, Lei; Chujo, Masahiko; Otomo, Atsushi; Ouchi, Eriko; Nagatomi, Ryoichi

    2016-02-01

    Few epidemiological studies have assessed the relationship between the traditional Japanese dietary pattern and longitudinal changes in cardiovascular disease risk factors among Japanese people. We designed a 3-year longitudinal study of 980 subjects living in Japan to evaluate how the Japanese dietary pattern is related to longitudinal changes in well-recognized risk factors for cardiovascular disease among apparently healthy Japanese adults. Dietary consumption was assessed via a validated food frequency questionnaire. Principal component analysis was used to derive three major dietary patterns-"Japanese," "sweets-fruits-cooked wheaten food," and "Izakaya (Japanese Pub)" from 39 food groups. After adjustment for potential confounders, the mean (95% confidence interval) for the change per year in diastolic blood pressure for men, systolic blood pressure, and diastolic blood pressure for women related to the "Japanese" dietary pattern factor score tertiles were 0.89 (0.10, 1.68), 2.25 (0.19, 4.31), and 0.75 (-1.00, 2.50) for the lowest tertile, 0.77 (-0.02, 1.56), 1.01 (-1.13, 3.15), and 0.44 (-1.38, 2.26) for the middle tertile and - 0.04 (-0.81, 0.72), -0.48 (-2.52, 1.56), and -0.77 (-2.51, 0.96) for the highest tertile (trend P value = 0.03, pattern factor score tertiles and the longitudinal change in serum triglyceride concentration only in men (trend P value = 0.02). Greater adherence to a traditional Japanese diet was independently related to a decreased change every year in diastolic blood pressure in men and women and in systolic blood pressure in women over a 3-year follow-up period. The findings suggest that the "Japanese" dietary pattern appeared to be related to a fall in blood pressure, which might have a beneficial effect on cardiovascular disease. A randomized trial is required to clarify the underlying mechanism.

  16. Longitudinal Study of the Transition From Healthy Aging to Alzheimer Disease

    Science.gov (United States)

    Johnson, David K.; Storandt, Martha; Morris, John C.; Galvin, James E.

    2009-01-01

    Background Detection of the earliest cognitive changes signifying Alzheimer disease is difficult. Objective To model the cognitive decline in preclinical Alzheimer disease. Design Longitudinal archival study comparing individuals who became demented during follow-up and people who remained nondemented on each of 4 cognitive factors: global, verbal memory, visuospatial, and working memory. Setting Alzheimer Disease Research Center, Washington University School of Medicine, St Louis, Missouri. Participants One hundred thirty-four individuals who became demented during follow-up and 310 who remained nondemented. Main Outcome Measures Inflection point in longitudinal cognitive performance. Results The best-fitting model for each of the 4 factors in the stable group was linear, with a very slight downward trend on all but the Visuospatial factor. In contrast, a piecewise model with accelerated slope after a sharp inflection point provided the best fit for the group that progressed. The optimal inflection point for all 4 factors was prior to diagnosis of dementia: Global, 2 years; Verbal and Working Memory, 1 year; and Visuospatial, 3 years. These results were also obtained when data were limited to the subset (n=44) with autopsy-confirmed Alzheimer disease. Conclusions There is a sharp inflection point followed by accelerating decline in multiple domains of cognition, not just memory, in the preclinical period in Alzheimer disease when there is insufficient cognitive decline to warrant clinical diagnosis using conventional criteria. Early change was seen in tests of visuospatial ability, most of which were speeded. Research into early detection of cognitive disorders using only episodic memory tasks may not be sensitive to all of the early manifestations of disease. PMID:19822781

  17. Longitudinal changes in awareness over 36 months in patients with mild Alzheimer's disease

    DEFF Research Database (Denmark)

    Vogel, Asmus; Waldorff, Frans Boch; Waldemar, Gunhild

    2015-01-01

    MMSE, Neuropsychiatric Inventory (NPI-Q), and Cornell scale for Depression in Dementia also were applied. Results: At 12 months, 26% had lower awareness rating as compared to baseline and at 36 months lower awareness ratings were found in 39%. At both visits, 16% had higher awareness rating as compared......Background: Longitudinal changes in awareness in dementia have been studied with short follow-up time and mostly in small patient groups (including patients with moderate dementia). We investigated awareness in patients with mild Alzheimer’s disease (AD) over 36 months and studied if a decline...

  18. A Longitudinal Study of Neurocognition in Dementia with Lewy Bodies Compared to Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Monica H. Breitve

    2018-03-01

    Full Text Available IntroductionThere are relatively few longitudinal studies on the differences in cognitive decline between Alzheimer’s disease (AD and dementia with Lewy bodies (DLB, and the majority of existing studies have suboptimal designs.AimWe investigated the differences in cognitive decline in AD compared to DLB over 4 years and cognitive domain predictors of progression.MethodsIn a longitudinal study, 266 patients with first-time diagnosis of mild dementia were included and followed annually. The patients were tested annually with neuropsychological tests and screening instruments [MMSE (Mini-Mental Status Examination, Clinical Dementia Rating (CDR, the second edition of California Verbal Learning Test (CVLT-II, Trail Making Test A & B (TMT A & B, Stroop test, Controlled Oral Word Associations Test (COWAT animal naming, Boston Naming Test, Visual Object and Space Perception Battery (VOSP Cubes and Silhouettes]. Longitudinal analyses were performed with linear mixed effects (LME models and Cox regression. Both specific neuropsychological tests and cognitive domains were analyzed.ResultsThis study sample comprised 119 AD and 67 DLB patients. In TMT A, the DLB patients had a faster decline over 4 years than patients with AD (p = 0.013. No other longitudinal differences in specific neuropsychological tests were found. Higher executive domain scores at baseline were associated with a longer time to reach severe dementia (CDR = 3 or death for the total sample (p = 0.032. High or low visuospatial function at baseline was not found to be associated with cognitive decline (MMSE or progression of dementia severity (CDR over time.ConclusionOver 4 years, patients with DLB had a faster decline in TMT A than patients with AD, but this should be interpreted cautiously. Beyond this, there was little support for faster decline in DLB patients neuropsychologically than in AD patients.

  19. Intimate Partner Violence and Welfare Participation: A Longitudinal Causal Analysis

    Science.gov (United States)

    Cheng, Tyrone C.

    2013-01-01

    This longitudinal study examined the temporal-ordered causal relationship between intimate partner violence (IPV), five mental disorders (depression, generalized anxiety disorder, social phobia, panic attack, posttraumatic stress disorder [PTSD]), alcohol abuse/dependence, drug abuse/ dependence, treatment seeking (from physician, counselor, and…

  20. Longitudinal Analysis of Academic Burnout in Korean Middle School Students.

    Science.gov (United States)

    Kim, Boyoung; Lee, Minyoung; Kim, Keunhwa; Choi, Hyunju; Lee, Sang Min

    2015-10-01

    The purpose of the study was to investigate the longitudinal relationships between the initial values and slopes of three dimensions of burnout syndrome (i.e. emotional exhaustion, cynicism and academic inefficacy). The study utilized four-wave longitudinal data from a total of 367 (81.6% response rate) middle school students in South Korea. Comprising a 6-month interval survey, the first survey was conducted in June 2010, the second in December 2010, the third in June 2011 and the fourth in December 2011. All participants were 13-year-olds at the first and second surveys, and 14-year-olds at the third and fourth surveys. The Maslach Burnout Inventory-Student Survey was used for each survey to assess the level of academic burnout. The longitudinal data were analysed using latent growth modelling. The results of the study indicated that high initial values (intercept) for emotional exhaustion were associated with a higher rate of increase (slope) in cynicism and academic inefficacy. On the other hand, high initial values for cynicism and academic inefficacy were associated with a lower rate of increase in the other dimensions. This longitudinal study should promote understanding of burned-out students and contribute to the literature by informing the design of prevention programmes for academic burnout. Copyright © 2014 John Wiley & Sons, Ltd.

  1. Statistical analysis of longitudinal network data with changing composition

    NARCIS (Netherlands)

    Huisman, M; Snijders, TAB; Snijders, Tom A.B.

    2003-01-01

    Markov chains can be used for the modeling of complex longitudinal network data. One class of probability models to model the evolution of social networks are stochastic actor-oriented models for network change proposed by Snijders. These models are continuous-time Markov chain models that are

  2. Secondary Analysis of National Longitudinal Transition Study 2 Data

    Science.gov (United States)

    Hicks, Tyler A.; Knollman, Greg A.

    2015-01-01

    This review examines published secondary analyses of National Longitudinal Transition Study 2 (NLTS2) data, with a primary focus upon statistical objectives, paradigms, inferences, and methods. Its primary purpose was to determine which statistical techniques have been common in secondary analyses of NLTS2 data. The review begins with an…

  3. A Longitudinal Analysis of Television Advertising Effects on Adolescents.

    Science.gov (United States)

    Moore, Roy L.; Moschis, George P.

    A longitudinal study examined both the short term and the long term effects of television advertising on the development of adolescents' consumption-related orientations. Questionnaires were administered to 556 adolescents in a number of schools in a southern state; a second wave of questionnaires was administered to a subsample of 230 of these…

  4. Longitudinal analysis of HIV risk behaviour patterns and their ...

    African Journals Online (AJOL)

    The goal of this study was to identify various HIV risk behaviours among tuberculosis (TB) patients in a longitudinal study design in South Africa. In 42 public primary healthcare facilities in three districts in three provinces, adult new TB and TB retreatment patients with hazardous or harmful alcohol use were interviewed ...

  5. Cardiovascular events in patients with atherothrombotic disease: a population-based longitudinal study in Taiwan.

    Directory of Open Access Journals (Sweden)

    Wen-Hsien Lee

    Full Text Available BACKGROUND: Atherothrombotic diseases including cerebrovascular disease (CVD, coronary artery disease (CAD, and peripheral arterial disease (PAD, contribute to the major causes of death in the world. Although several studies showed the association between polyvascular disease and poor cardiovascular (CV outcomes in Asian population, there was no large-scale study to validate this relationship in this population. METHODS AND RESULTS: This retrospective cohort study included patients with a diagnosis of CVD, CAD, or PAD from the database contained in the Taiwan National Health Insurance Bureau during 2001-2004. A total of 19954 patients were enrolled in this study. The atherothrombotic disease score was defined according to the number of atherothrombotic disease. The study endpoints included acute coronary syndrome (ACS, all strokes, vascular procedures, in hospital mortality, and so on. The event rate of ischemic stroke (18.2% was higher than that of acute myocardial infarction (5.7% in our patients (P = 0.0006. In the multivariate Cox regression analyses, the adjusted hazard ratios (HRs of each increment of atherothrombotic disease score in predicting ACS, all strokes, vascular procedures, and in hospital mortality were 1.41, 1.66, 1.30, and 1.14, respectively (P≦0.0169. CONCLUSIONS: This large population-based longitudinal study in patients with atherothrombotic disease demonstrated the risk of subsequent ischemic stroke was higher than that of subsequent AMI. In addition, the subsequent adverse CV events including ACS, all stroke, vascular procedures, and in hospital mortality were progressively increased as the increase of atherothrombotic disease score.

  6. Comparing Longitudinal Profile Patterns of Mathematics and Reading in Early Child Longitudinal Study, Kindergarten: The Profile Analysis via Multidimensional Scaling (PAMS) Approach

    Science.gov (United States)

    Kim, Se-Kang

    2010-01-01

    The aim of the study is to compare longitudinal patterns from Mathematics and Reading data from the direct child assessment of Early Child Longitudinal Study, Kindergarten (ECLS-K, US Department of Education, National Center for Education Statistics 2006), utilizing Profile Analysis via Multidimensional Scaling (PAMS). PAMS has been used initially…

  7. A longitudinal study of neuromelanin-sensitive magnetic resonance imaging in Parkinson's disease.

    Science.gov (United States)

    Matsuura, Keita; Maeda, Masayuki; Tabei, Ken-Ichi; Umino, Maki; Kajikawa, Hiroyuki; Satoh, Masayuki; Kida, Hirotaka; Tomimoto, Hidekazu

    2016-10-28

    Neuromelanin-sensitive MR imaging (NMI) is an increasingly powerful tool for the diagnosis of Parkinson's disease (PD). This study was undertaken to evaluate longitudinal changes on NMI in PD patients. We examined longitudinal changes on NMI in 14 PD patients. The area and contrast ratio (CR) of the substantia nigra pars compacta (SNc) were comparatively analyzed. The total area and CR of the SNc upon follow-up NMI were significantly smaller than those on initial NMI (from 33.5±18.9 pixels and 6.35±2.86% to 21.5±16.7 pixels and 4.19±2.11%; Wilcoxon signed-rank test, pWilcoxon signed-rank test, p=0.002 and p=0.007, respectively). On a case-by-case basis, the area of the SNc invariably decreased upon follow-up NMI in all patients. We further demonstrated that the total area and CR of the SNc negatively correlated with disease duration (Pearson correlation coefficient, r=-0.63, p<0.001 and r=-0.41, p=0.031, respectively). In area analyses, our results demonstrated very high intraclass correlation coefficients for both intra- and inter-rater reliability. NMI is a useful and reliable tool for detecting neuropathological changes over time in PD patients. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Analysis of longitudinal diffusion-weighted images in healthy and pathological aging: An ADNI study.

    Science.gov (United States)

    Kruggel, Frithjof; Masaki, Fumitaro; Solodkin, Ana

    2017-02-15

    The widely used framework of voxel-based morphometry for analyzing neuroimages is extended here to model longitudinal imaging data by exchanging the linear model with a linear mixed-effects model. The new approach is employed for analyzing a large longitudinal sample of 756 diffusion-weighted images acquired in 177 subjects of the Alzheimer's Disease Neuroimaging initiative (ADNI). While sample- and group-level results from both approaches are equivalent, the mixed-effect model yields information at the single subject level. Interestingly, the neurobiological relevance of the relevant parameter at the individual level describes specific differences associated with aging. In addition, our approach highlights white matter areas that reliably discriminate between patients with Alzheimer's disease and healthy controls with a predictive power of 0.99 and include the hippocampal alveus, the para-hippocampal white matter, the white matter of the posterior cingulate, and optic tracts. In this context, notably the classifier includes a sub-population of patients with minimal cognitive impairment into the pathological domain. Our classifier offers promising features for an accessible biomarker that predicts the risk of conversion to Alzheimer's disease. Data used in preparation of this article were obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database (adni.loni.usc.edu). As such, the investigators within the ADNI contributed to the design and implementation of ADNI and/or provided data but did not participate in analysis or writing of this report. A complete listing of ADNI investigators can be found at: http://adni.loni.usc.edu/wp-content/uploads/how to apply/ADNI Acknowledgement List.pdf. Significance statement This study assesses neuro-degenerative processes in the brain's white matter as revealed by diffusion-weighted imaging, in order to discriminate healthy from pathological aging in a large sample of elderly subjects. The analysis of time

  9. [The Load of Injustice: A Longitudinal Analysis of the Impact of Subjectively Perceived Income Injustice on the Risk of Stress-Associated Diseases Based on the German Socio-Economic Panel Study].

    Science.gov (United States)

    Boscher, Claudia; Arnold, Laura; Lange, Andreas; Szagun, Bertram

    2018-03-01

    Income injustice is regarded as a psychosocial strain and associated with an increased risk of stress-related diseases. The physiological stress response is thereby considered as a central link. The aim of the study is to reveal the influence of subjectively perceived income injustice on stress-associated diseases, taking into consideration the load duration. Based on the German Socio-Economic Panel Study, data on 5,657 workers in the survey years 2005-2013 were analyzed. The dependent variable reflect the doctor's diagnosed new cases of diabetes, asthma, cardiopathy, stroke, hypertension and depression in the years 2009-2013 as an index. Key predictor is the injustice perception of one's income. In order to operationalize the duration of the injustice perception, the values of the variable for the years 2005, 2007 and 2009 were accumulated. Using logit models, stratified for gender and volume of employment, factors were identified that affect the probability of stress-related diseases. If income was perceived as unjust for over 5 years, the odds of stress-related diseases were strongly enhanced for women (OR 1.64; 95% CI 1.17-2.30). Women working full-time seemed to be particularly affected (OR 2.43; 95% CI 1.54-3.84). Men working full-time perceiving their income as unjust also showed an increased risk for stress diseases (OR 1.43; CI 1.03-1.98). The more often income was assessed as unjust, the higher was the probability of stress-related diseases. Perceived income injustice seems to be a significant risk factor for stress-related diseases within a dose-response relationship with increasing duration of exposure. Findings of stress research indicate that this represents the 'allostatic load'. Gender-specific differences in stress reaction as well as in the appraisal of the stressors can be associated with gender-specific work and life conditions and therefore provide explanatory approaches for the revealed effects. © Georg Thieme Verlag KG Stuttgart · New York.

  10. Natural History of Parkinson's Disease in the Province of Segovia: Disability in a 20 Years Longitudinal Study.

    Science.gov (United States)

    Duarte, Jacinto; García Olmos, Luis Miguel; Mendoza, Amelia; Martínez Pueyo, Ángel; Clavería, Luis Erik

    2015-01-01

    Parkinson's disease mainly affects the elderly population causing a progressive functional disability with motor, psychic, and cognitive deterioration. This study was carried out to evaluate disability caused by Parkinson's disease by analyzing the median time to reach Hoehn and Yahr stage III and to investigate predictor variables based on a 20-year longitudinal follow-up study. We examined 273 patients with Parkinson's disease recruited between 1978 and 1998. We performed a survival analysis using the Kaplan-Meier method to determine the time to disability and we used a Cox regression model to adjust prognosis factors. The median time to reach Hoehn and Yahr stage III was 7.73 years (95% CI: 5.95-8.05). Independent predictors of disability were: age at onset, the hazard ratio (HR) = 1.10, 95% CI: 1.08-1.12; UPDRS II (activities of daily living) HR = 1.08, 95% CI: 1.03-1.14; and akinesia and rigidity at onset HR = 1.55, 95% CI: 1.07-2.24. Patients with Parkinson's disease evolve gradually toward disability, and prognostic factors of this evolution were identified. © 2015 S. Karger AG, Basel.

  11. PARAMETRIC ANALYSIS OF LONGITUDINAL STABILITY UNMANNED AERIAL VEHICLE

    Directory of Open Access Journals (Sweden)

    Ievgen Udartsev

    2013-10-01

    Full Text Available 1024x768 We consider the aerodynamic characteristics of unmanned aircraft container type, which were obtained in a wind tunnel and refined amended by soot blowing elements propeller system and the influence of the earth's surface. The estimation of longitudinal static stability and its dependence on altitude, damping, coordinates of center of gravity, shoulder horizontal tail, wings rejection of mechanization. The variation of these parameters enables to optimize balancing system with minimal losses. Normal 0 false false false

  12. Longitudinal acoustic instabilities in slender solid propellant rockets : linear analysis

    OpenAIRE

    García Schafer, Juan Esteban; Liñán Martínez, Amable

    2001-01-01

    To describe the acoustic instabilities in the combustion chambers of laterally burning solid propellant rockets the interaction of the mean flow with the acoustic waves is analysed, using multiple scale techniques, for realistic cases in which the combustion chamber is slender and the nozzle area is small compared with the cross-sectional area of the chamber. Associated with the longitudinal acoustic oscillations we find vorticity and entropy waves, with a wavelength typically small compared ...

  13. Ethical Code Effectiveness in Football Clubs: A Longitudinal Analysis

    OpenAIRE

    Constandt, Bram; De Waegeneer, Els; Willem, Annick

    2017-01-01

    As football (soccer) clubs are facing different ethical challenges, many clubs are turning to ethical codes to counteract unethical behaviour. However, both in- and outside the sport field, uncertainty remains about the effectiveness of these ethical codes. For the first time, a longitudinal study design was adopted to evaluate code effectiveness. Specifically, a sample of non-professional football clubs formed the subject of our inquiry. Ethical code effectiveness was...

  14. Regional Cerebral Disease Progression in Friedreich's Ataxia: A Longitudinal Diffusion Tensor Imaging Study.

    Science.gov (United States)

    Mascalchi, Mario; Toschi, Nicola; Giannelli, Marco; Ginestroni, Andrea; Della Nave, Riccardo; Tessa, Carlo; Piacentini, Silvia; Dotti, Maria Teresa; Aiello, Marco; Nicolai, Emanuele; Soricelli, Andrea; Salvi, Fabrizio; Diciotti, Stefano

    2016-01-01

    Imaging biomarkers of disease progression are desirable in inherited ataxias. MRI has demonstrated brain damage in Friedreich ataxia (FRDA) in form of regional atrophy of the medulla, peridentate cerebellar white matter (WM) and superior cerebellar peduncles (visible in T1-weighted images) and of change of microstructural characteristics of WM tracts of the brainstem, cerebellar peduncles, cerebellum, and supratentorial structures (visible through diffusion-weighted imaging). We explored the potential of brain MR morphometry and diffusion tensor imaging (DTI) to track the progression of neurodegeneration in FRDA. Eight patients (5F, 3M; age 13.4-41.2 years) and 8 healthy controls (2F, 6M; age 26.2-48.3 years) underwent 2 MRI examinations (mean 3.9 and 4.1 years apart, respectively) on the same 1.5T scanner. The protocol included 3D T1-weighted images and axial diffusion-weighted images (b-value 1,000 s/mm(2)) for calculating maps of fractional anisotropy, mean, axial and radial diffusivity, and mode of anisotropy. Tensor-based morphometry was used to investigate regional volume changes and tract-based spatial statistics was used to investigate microstructural changes in WM tracts. Longitudinal analyses showed no differences in regional volume changes but a significant difference in axial diffusivity changes in cerebral and corpus callosum WM of patients as compared to controls (mean longitudinal rate of change for axial diffusivity: -.02 × 10(-3) mm(2)/s/year in patients vs. .01 × 10(-3) mm(2)/s/year in controls). No correlation with number of triplets, disease duration, and worsening of the clinical deficit was observed. DTI can track brain microstructural changes in FRDA and can be considered a potential biomarker of disease progression. Copyright © 2015 by the American Society of Neuroimaging.

  15. CHI: A contemporaneous health index for degenerative disease monitoring using longitudinal measurements.

    Science.gov (United States)

    Huang, Yijun; Meng, Qiang; Evans, Heather; Lober, William; Cheng, Yu; Qian, Xiaoning; Liu, Ji; Huang, Shuai

    2017-09-01

    In this paper, we develop a novel formulation for contemporaneous patient risk monitoring by exploiting the emerging data-rich environment in many healthcare applications, where an abundance of longitudinal data that reflect the degeneration of the health condition can be continuously collected. Our objective, and the developed formulation, is fundamentally different from many existing risk score models for different healthcare applications, which mostly focus on predicting the likelihood of a certain outcome at a pre-specified time. Rather, our formulation translates multivariate longitudinal measurements into a contemporaneous health index (CHI) that captures patient condition changes over the course of progression. Another significant feature of our formulation is that, CHI can be estimated with or without label information, different from other risk score models strictly based on supervised learning. To develop this formulation, we focus on the degenerative disease conditions, for which we could utilize the monotonic progression characteristic (either towards disease or recovery) to learn CHI. Such a domain knowledge leads us to a novel learning formulation, and on top of that, we further generalize this formulation with a capacity to incorporate label information if available. We further develop algorithms to mitigate the challenges associated with the nonsmooth convex optimization problem by first identifying its dual reformulation as a constrained smooth optimization problem, and then, using the block coordinate descent algorithm to iteratively solve the optimization with a derived efficient projection at each iteration. Extensive numerical studies are performed on both synthetic datasets and real-world applications on Alzheimer's disease and Surgical Site Infection, which demonstrate the utility and efficacy of the proposed method on degenerative conditions that include a wide range of applications. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Longitudinal grey and white matter changes in frontotemporal dementia and Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Lars Frings

    Full Text Available Behavioural variant frontotemporal dementia (bvFTD and Alzheimer's disease (AD dementia are characterised by progressive brain atrophy. Longitudinal MRI volumetry may help to characterise ongoing structural degeneration and support the differential diagnosis of dementia subtypes. Automated, observer-independent atlas-based MRI volumetry was applied to analyse 102 MRI data sets from 15 bvFTD, 14 AD, and 10 healthy elderly control participants with consecutive scans over at least 12 months. Anatomically defined targets were chosen a priori as brain structures of interest. Groups were compared regarding volumes at clinic presentation and annual change rates. Baseline volumes, especially of grey matter compartments, were significantly reduced in bvFTD and AD patients. Grey matter volumes of the caudate and the gyrus rectus were significantly smaller in bvFTD than AD. The bvFTD group could be separated from AD on the basis of caudate volume with high accuracy (79% cases correct. Annual volume decline was markedly larger in bvFTD and AD than controls, predominantly in white matter of temporal structures. Decline in grey matter volume of the lateral orbitofrontal gyrus separated bvFTD from AD and controls. Automated longitudinal MRI volumetry discriminates bvFTD from AD. In particular, greater reduction of orbitofrontal grey matter and temporal white matter structures after 12 months is indicative of bvFTD.

  17. Sensitivity analysis of longitudinal cracking on asphalt pavement using MEPDG in permafrost region

    Directory of Open Access Journals (Sweden)

    Chen Zhang

    2015-02-01

    Full Text Available Longitudinal cracking is one of the most important distresses of asphalt pavement in permafrost regions. The sensitivity analysis of design parameters for asphalt pavement can be used to study the influence of every parameter on longitudinal cracking, which can help optimizing the design of the pavement structure. In this study, 20 test sections of Qinghai–Tibet Highway were selected to conduct the sensitivity analysis of longitudinal cracking on material parameter based on Mechanistic-Empirical Pavement Design Guide (MEPDG and single factorial sensitivity analysis method. Some computer aided engineering (CAE simulation techniques, such as the Latin hypercube sampling (LHS technique and the multiple regression analysis are used as auxiliary means. Finally, the sensitivity spectrum of material parameter on longitudinal cracking was established. The result shows the multiple regression analysis can be used to determine the remarkable influence factor more efficiently and to process the qualitative analysis when applying the MEPDG software in sensitivity analysis of longitudinal cracking in permafrost regions. The effect weights of the three parameters on longitudinal cracking in descending order are air void, effective binder content and PG grade. The influence of air void on top layer is bigger than that on middle layer and bottom layer. The influence of effective asphalt content on top layer is bigger than that on middle layer and bottom layer, and the influence of bottom layer is slightly bigger than middle layer. The accumulated value of longitudinal cracking on middle layer and bottom layer in the design life would begin to increase when the design temperature of PG grade increased.

  18. Development of Inflammatory Bowel Disease Is Linked to a Longitudinal Restructuring of the Gut Metagenome in Mice

    OpenAIRE

    Sharpton, T; Lyalina, S; Luong, J; Pham, J; Deal, EM; Armour, C; Gaulke, C; Sanjabi, S; Pollard, KS

    2017-01-01

    ABSTRACT The gut microbiome is linked to inflammatory bowel disease (IBD) severity and altered in late-stage disease. However, it is unclear how gut microbial communities change over the course of IBD development, especially in regard to function. To investigate microbiome-mediated disease mechanisms and discover early biomarkers of IBD, we conducted a longitudinal metagenomic investigation in an established mouse model of IBD, where damped transforming growth factor ? (TGF-?) signaling in T ...

  19. Development of Inflammatory Bowel Disease is Linked to a Longitudinal Restructuring of the Gut Metagenome in Mice

    OpenAIRE

    Luong, Julie; Sharpton, Thomas; Pollard, Katherine; Sanjabi, Shomyseh; Gaulke, Christopher; Armour, Courtney; Deal, Emily; Pham, Joey; Loung, Julie; Lyalina, Svetlana; Sharpton, Thomas

    2017-01-01

    The gut microbiome is linked to inflammatory bowel disease (IBD) severity and altered in late stage disease. However, it is unclear how gut microbial communities change over the course of IBD development, especially in regards to function. To investigate microbiome mediated disease mechanisms and discover early biomarkers of IBD, we conducted a longitudinal metagenomic investigation in an established mouse model of IBD, where dampened TGF-β signaling in T cells leads to peripheral immune acti...

  20. How do innovators stay innovative? A longitudinal case analysis

    OpenAIRE

    Tuzovic, Sven; Wirtz, Jochen; Heracleous, Loizos Th.

    2018-01-01

    Purpose – How can some companies be the innovation leader in their industry over prolonged periods of time, while others cannot? The purpose of this study is to understand a firm’s capability to be a successful serial innovator and to generate a constant stream of industry-leading innovations.\\ud \\ud Design/Methodology/Approach – The paper uses a longitudinal case study approach to gain an understanding of what and how Singapore Airlines (SIA) sustained service innovation for over 30 years. T...

  1. Total Longitudinal Moment Calculation and Reliability Analysis of Yacht Structures

    Science.gov (United States)

    Zhi, Wenzheng; Lin, Shaofen

    In order to check the reliability of the yacht in FRP (Fiber Reinforce Plastic) materials, in this paper, the vertical force and the calculation method of the overall longitudinal bending moment on yacht was analyzed. Specially, this paper focuses on the impact of speed on the still water bending moment on yacht. Then considering the mechanical properties of the cap type stiffeners in composite materials, the ultimate bearing capacity of the yacht has been worked out, finally the reliability of the yacht was calculated with using response surface methodology. The result can be used in yacht design and yacht driving.

  2. Application of pattern mixture models to address missing data in longitudinal data analysis using SPSS.

    Science.gov (United States)

    Son, Heesook; Friedmann, Erika; Thomas, Sue A

    2012-01-01

    Longitudinal studies are used in nursing research to examine changes over time in health indicators. Traditional approaches to longitudinal analysis of means, such as analysis of variance with repeated measures, are limited to analyzing complete cases. This limitation can lead to biased results due to withdrawal or data omission bias or to imputation of missing data, which can lead to bias toward the null if data are not missing completely at random. Pattern mixture models are useful to evaluate the informativeness of missing data and to adjust linear mixed model (LMM) analyses if missing data are informative. The aim of this study was to provide an example of statistical procedures for applying a pattern mixture model to evaluate the informativeness of missing data and conduct analyses of data with informative missingness in longitudinal studies using SPSS. The data set from the Patients' and Families' Psychological Response to Home Automated External Defibrillator Trial was used as an example to examine informativeness of missing data with pattern mixture models and to use a missing data pattern in analysis of longitudinal data. Prevention of withdrawal bias, omitted data bias, and bias toward the null in longitudinal LMMs requires the assessment of the informativeness of the occurrence of missing data. Missing data patterns can be incorporated as fixed effects into LMMs to evaluate the contribution of the presence of informative missingness to and control for the effects of missingness on outcomes. Pattern mixture models are a useful method to address the presence and effect of informative missingness in longitudinal studies.

  3. Relationship between white matter lesions and regional cerebral blood flow changes during longitudinal follow up in Alzheimer's disease.

    Science.gov (United States)

    Hanaoka, Takuya; Kimura, Noriyuki; Aso, Yasuhiro; Takemaru, Makoto; Kimura, Yuki; Ishibashi, Masato; Matsubara, Etsuro

    2016-07-01

    The aim of the present study was to evaluate the relationship between baseline white matter lesions (WML) and changes in regional cerebral blood flow during longitudinal follow up of patients with Alzheimer's disease (AD). A total of 38 patients with AD were included in the study (16 men, 22 women; mean age 77.8 years). All patients were evaluated using the Mini-Mental State Examination and brain perfusion single-photon emission computed tomography at baseline with an approximately 2-year follow up. The patients were divided into two subgroups according to the presence of WML on magnetic resonance imaging. Single-photon emission computed tomography data were analyzed using a voxel-by-voxel group analysis with Statistical Parametric Mapping 8 and region of interest analysis using FineSRT. Changes in Mini-Mental State Examination scores and regional cerebral blood flow were analyzed using the Wilcoxon signed-rank test. Mean Mini-Mental State Examination scores in AD patients with WML significantly decreased from 19.4 ± 4.8 to 15.5 ± 6.5 (P = 0.003). Statistical Parametric Mapping 8 and FineSRT analysis showed more severe and widespread regional cerebral blood flow reduction, mainly in the frontal and mesial temporal regions in AD patients with WML compared with those without WML. Baseline WML could predict a rapid progression of cognitive and brain functional impairment during longitudinal follow up in AD. Geriatr Gerontol Int 2016; 16: 836-842. © 2015 Japan Geriatrics Society.

  4. Longitudinal changes in task-evoked brain responses in Parkinson’s disease patients with and without mild cognitive impairment

    Directory of Open Access Journals (Sweden)

    Urban eEkman

    2014-07-01

    Full Text Available Cognitive deficits are common in Parkinson’s disease. Previous cross-sectional research has demonstrated a link between cognitive impairments and fronto-striatal dopaminergic dysmodulation. However, longitudinal studies that link disease progression with altered task-evoked brain activity are lacking. Therefore, our objective was to longitudinally evaluate working-memory related brain activity changes in Parkinson’s disease patients with and without mild cognitive impairment.Patients were recruited within a longitudinal cohort study of incident patients with idiopathic parkinsonism. We longitudinally (at baseline examination and at 12-months follow-up compared 28 patients with Parkinson’s disease without mild cognitive impairment with 11 patients with Parkinson’s disease and mild cognitive impairment. Functional MRI blood oxygen level dependent signal was measured during a verbal two-back working-memory task. Patients with mild cognitive impairment under-recruited bilateral medial prefrontal cortex, right putamen, and lateral parietal cortex at both time-points (main effect of group: p<0.001, uncorrected. Critically, a significant group-by-time interaction effect (p<0.001, uncorrected was found in the right fusiform gyrus, indicating that working-memory related activity decreased for patients with Parkinson’s disease and mild cognitive impairment between baseline and follow-up, while patients without mild cognitive impairment were stable across time-points. The functional connectivity between right fusiform gyrus and bilateral caudate nucleus was stronger for patients without MCI relative to patients with MCI.Our findings support the view that deficits in working-memory updating are related to persistent fronto-striatal under-recruitments in patients with early phase Parkinson’s disease and mild cognitive impairment. The longitudinal evolution of mild cognitive impairment in Parkinson’s disease translates into additional task

  5. Longitudinal cognitive decline in subcortical ischemic vascular disease--the LADIS Study

    DEFF Research Database (Denmark)

    Jokinen, Hanna; Kalska, Hely; Ylikoski, Raija

    2009-01-01

    BACKGROUND: Cross-sectional studies have indicated that subcortical ischemic vascular disease (SIVD), as defined according to imaging criteria, is associated with a specific clinical and cognitive profile. Much less is known about the long-term cognitive consequences of SIVD. The aim of the study...... was to investigate the longitudinal cognitive performance and incident dementia in subjects with and without SIVD in a sample of older adults with white matter lesions. METHODS: In the Leukoaraiosis and Disability (LADIS) study, 639 participants were examined with annual clinical and neuropsychological evaluations...... for 3 years. The subjects meeting the MRI criteria of SIVD at baseline were compared to the other subjects of the sample with linear mixed models. RESULTS: The overall level of cognitive performance over the follow-up period was inferior in multiple cognitive domains in SIVD subjects as compared...

  6. Combined Circumferential and Longitudinal Left Ventricular Systolic Dysfunction in Patients with Rheumatoid Arthritis without Overt Cardiac Disease.

    Science.gov (United States)

    Cioffi, Giovanni; Viapiana, Ombretta; Ognibeni, Federica; Dalbeni, Andrea; Gatti, Davide; Mazzone, Carmine; Faganello, Giorgio; Di Lenarda, Andrea; Adami, Silvano; Rossini, Maurizio

    2016-07-01

    Patients with rheumatoid arthritis have an increased risk for cardiovascular disease. Because of accelerated atherosclerosis and changes in left ventricular (LV) geometry, circumferential and longitudinal (C&L) LV systolic dysfunction (LVSD) may be impaired in these patients despite preserved LV ejection fraction. The aim of this study was to determine the prevalence of and factors associated with combined C&L LVSD in patients with rheumatoid arthritis. One hundred ninety-eight outpatients with rheumatoid arthritis without overt cardiac disease were prospectively analyzed from January through June 2014 and compared with 198 matched control subjects. C&L systolic function was evaluated by stress-corrected midwall shortening (sc-MS) and tissue Doppler mitral annular peak systolic velocity (S'). Combined C&L LVSD was defined if sc-MS was cite either of them in the other one and, afterward, we just did not think about this point anymore. Of note, the idea to combine in the analysis longitudinal function came therefore well after the starting process of revision of the paper E and was, in some way inspired by a reviewer's comment. That is why we did not put both findings in the same paper. We think that our explanations provide the broad audience of your journal a perspective of transparency and our respect for the readers' right to understand how the work described in the paper J relates to other work by our research group. Giovanni Cioffi On behalf of all co-authors Ombretta Viapiana, Federica Ognibeni, Andrea Dalbeni, Davide Gatti, Carmine Mazzone, Giorgio Faganello, Andrea Di Lenarda, Silvano Adami, and Maurizio Rossini. Copyright © 2016 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

  7. Chronic disease prevalence in women and air pollution--A 30-year longitudinal cohort study.

    Science.gov (United States)

    To, Teresa; Zhu, Jingqin; Villeneuve, Paul J; Simatovic, Jacqueline; Feldman, Laura; Gao, Chenwei; Williams, Devon; Chen, Hong; Weichenthal, Scott; Wall, Claus; Miller, Anthony B

    2015-07-01

    Air pollution, such as fine particulate matter (PM2.5), can increase risk of adverse health events among people with heart disease, diabetes, asthma and chronic obstructive pulmonary disease (COPD) by aggravating these conditions. Identifying the influence of PM2.5 on prevalence of these conditions may help target interventions to reduce disease morbidity among high-risk populations. The objective of this study is to measure the association of exposure of PM2.5 with prevalence risk of various chronic diseases among a longitudinal cohort of women. Women from Ontario who enrolled in the Canadian National Breast Screening Study (CNBSS) from 1980 to 1985 (n = 29,549) were linked to provincial health administrative data from April 1, 1992 to March 31, 2013 to determine the prevalence of major chronic disease and conditions (heart disease, diabetes, asthma, COPD, acute myocardial infarction, angina, stroke and cancers). Exposure to PM2.5 was measured using satellite data collected from January 1, 1998 to December 31, 2006 and assigned to resident postal-code at time of entry into study. Poisson regression models were used to describe the relationship between exposure to ambient PM2.5 and chronic disease prevalence. Prevalence rate ratios (PRs) were estimated while adjusting for potential confounders: baseline age, smoking, BMI, marital status, education and occupation. Separate models were run for each chronic disease and condition. Congestive heart failure (PR = 1.31, 95% CI: 1.13, 1.51), diabetes (PR = 1.28, 95% CI: 1.16, 1.41), ischemic heart disease (PR = 1.22, 95% CI: 1.14, 1.30), and stroke (PR = 1.21, 95% CI: 1.09, 1.35) showed over a 20% increase in PRs per 10 μg/m(3) increase in PM2.5 after adjusting for risk factors. Risks were elevated in smokers and those with BMI greater than 30. This study estimated significant elevated prevalent rate ratios per unit increase in PM2.5 in nine of the ten chronic diseases studied. Copyright © 2015 Elsevier Ltd. All rights

  8. Longitudinal Modeling of Functional Decline Associated with Pathologic Alzheimer's Disease in Older Persons without Cognitive Impairment.

    Science.gov (United States)

    Wang, Dai; Schultz, Tim; Novak, Gerald P; Baker, Susan; Bennett, David A; Narayan, Vaibhav A

    2018-01-01

    Therapeutic research on Alzheimer's disease (AD) has moved to intercepting the disease at the preclinical phase. Most drugs in late development have focused on the amyloid hypothesis. To understand the magnitude of amyloid-related functional decline and to identify the functional domains sensitive to decline in a preclinical AD population. Data were from the Religious Orders Study and the Rush Memory and Aging Project. Cognitive decline was measured by a modified version of the Alzheimer's Disease Cooperative Study Preclinical Alzheimer Cognitive Composite. The trajectories of functional decline, as measured by the instrumental and basic activities of daily living, were longitudinally modeled in 484 participants without cognitive impairment at baseline and having both a final clinical and a postmortem neuropathology assessment of AD. Individuals with different final clinical diagnoses had different trajectories of cognitive and functional decline. Individuals with AD dementia, minor cognitive impairment, and no cognitive impairment had the most, intermediate, and least declines. While individuals with pathologic AD had significantly more cognitive decline over time than those without, the magnitude of difference in functional decline between these two groups was small. Functional domains such as handling finance and handling medications were more sensitive to decline. Demonstrating the functional benefit of an amyloid-targeting drug represents a significant challenge as elderly people experience functional decline due to a wide range of reasons with limited manifestation attributable to AD neuropathology. More sensitive functional scales focusing on the functional domains sensitive to decline in preclinical AD are needed.

  9. Evaluation of longitudinal 12 and 24 month cognitive outcomes in premanifest and early Huntington's disease.

    Science.gov (United States)

    Stout, Julie C; Jones, Rebecca; Labuschagne, Izelle; O'Regan, Alison M; Say, Miranda J; Dumas, Eve M; Queller, Sarah; Justo, Damian; Santos, Rachelle Dar; Coleman, Allison; Hart, Ellen P; Dürr, Alexandra; Leavitt, Blair R; Roos, Raymund A; Langbehn, Doug R; Tabrizi, Sarah J; Frost, Chris

    2012-07-01

    Deterioration of cognitive functioning is a debilitating symptom in many neurodegenerative diseases, such as Huntington's disease (HD). To date, there are no effective treatments for the cognitive problems associated with HD. Cognitive assessment outcomes will have a central role in the efforts to develop treatments to delay onset or slow the progression of the disease. The TRACK-HD study was designed to build a rational basis for the selection of cognitive outcomes for HD clinical trials. There were a total of 349 participants, including controls (n=116), premanifest HD (n=117) and early HD (n=116). A standardised cognitive assessment battery (including nine cognitive tests comprising 12 outcome measures) was administered at baseline, and at 12 and 24 months, and consisted of a combination of paper and pencil and computerised tasks selected to be sensitive to cortical-striatal damage or HD. Each cognitive outcome was analysed separately using a generalised least squares regression model. Results are expressed as effect sizes to permit comparisons between tasks. 10 of the 12 cognitive outcomes showed evidence of deterioration in the early HD group, relative to controls, over 24 months, with greatest sensitivity in Symbol Digit, Circle Tracing direct and indirect, and Stroop word reading. In contrast, there was very little evidence of deterioration in the premanifest HD group relative to controls. The findings describe tests that are sensitive to longitudinal cognitive change in HD and elucidate important considerations for selecting cognitive outcomes for clinical trials of compounds aimed at ameliorating cognitive decline in HD.

  10. The impact of unrecognized autoimmune rheumatic diseases on the incidence of preeclampsia and fetal growth restriction: a longitudinal cohort study.

    Science.gov (United States)

    Spinillo, Arsenio; Beneventi, Fausta; Locatelli, Elena; Ramoni, Vèronique; Caporali, Roberto; Alpini, Claudia; Albonico, Giulia; Cavagnoli, Chiara; Montecucco, Carlomaurizio

    2016-10-18

    The burden of pregnancy complications associated with well defined, already established systemic rheumatic diseases preexisting pregnancy such as rheumatoid arthritis, systemic lupus erythematosus or scleroderma is well known. Systemic rheumatic diseases are characterized by a long natural history with few symptoms, an undifferentiated picture or a remitting course making difficult a timely diagnosis. It has been suggested that screening measures for these diseases could be useful but the impact of unrecognized systemic rheumatic disorders on pregnancy outcome is unknown. The objective of the study was to evaluate the impact of previously unrecognized systemic autoimmune rheumatic on the incidence of preeclampsia and fetal growth restriction (FGR). A longitudinal cohort-study with enrolment during the first trimester of pregnancy of women attending routine antenatal care using a two-step approach with a self-reported questionnaire, autoantibody detection and clinical evaluation of antibody-positive subjects. The incidence of FGR and preeclampsia in subjects with newly diagnosed rheumatic diseases was compared to that of selected negative controls adjusting for potential confounders by logistic regression analysis. The prevalence of previously unrecognized systemic rheumatic diseases was 0.4 % for rheumatoid arthritis (19/5232), 0.25 % (13/5232) for systemic lupus erythematosus, 0.31 % (16/5232) for Sjögren's syndrome, 0.3 % for primary antiphospholipid syndrome (14/5232) and 0.11 % (6/5232) for other miscellaneous diseases. Undifferentiated connective tissue disease was diagnosed in an additional 131 subjects (2.5 %). The incidence of either FGR or preeclampsia was 6.1 % (36/594) among controls and 25.3 % (50/198) in subjects with unrecognized rheumatic diseases (excess incidence = 3.9 % (95 % CI = 2.6-9.6) or 34 % (95 % CI = 22-44) of all cases of FGR/preeclampsia). The incidence of small for gestational age infant (SGA) was higher among

  11. Bifurcation analysis and stability design for aircraft longitudinal motion with high angle of attack

    Directory of Open Access Journals (Sweden)

    Xin Qi

    2015-02-01

    Full Text Available Bifurcation analysis and stability design for aircraft longitudinal motion are investigated when the nonlinearity in flight dynamics takes place severely at high angle of attack regime. To predict the special nonlinear flight phenomena, bifurcation theory and continuation method are employed to systematically analyze the nonlinear motions. With the refinement of the flight dynamics for F-8 Crusader longitudinal motion, a framework is derived to identify the stationary bifurcation and dynamic bifurcation for high-dimensional system. Case study shows that the F-8 longitudinal motion undergoes saddle node bifurcation, Hopf bifurcation, Zero-Hopf bifurcation and branch point bifurcation under certain conditions. Moreover, the Hopf bifurcation renders series of multiple frequency pitch oscillation phenomena, which deteriorate the flight control stability severely. To relieve the adverse effects of these phenomena, a stabilization control based on gain scheduling and polynomial fitting for F-8 longitudinal motion is presented to enlarge the flight envelope. Simulation results validate the effectiveness of the proposed scheme.

  12. Longitudinal patterns of predominant asthma disease activity in pediatric patients enrolled in an asthma-specific disease management program.

    Science.gov (United States)

    Scott, Lyne; Nichols, Breck; Choi Kwong, Kenny Yat; Morphew, Tricia; Jones, Craig A

    2008-08-01

    To determine if patterns of predominant asthma disease activity are more closely related than baseline asthma severity to measures of morbidity (acute asthma attack, emergency room visit/hospitalization, missed school days, and/or steroid burst). Retrospective analysis was performed for inner-city Los Angeles asthmatic children (3 to 18 years of age) during their first year of enrollment in an asthma-specific disease management program. All measures of morbidity were more closely related to patterns of predominant disease activity than baseline severity. We conclude that patterns of predominant disease activity are a more significant predictor of asthma morbidity than is baseline severity.

  13. Tract specific analysis in patients with sickle cell disease

    Science.gov (United States)

    Chai, Yaqiong; Coloigner, Julie; Qu, Xiaoping; Choi, Soyoung; Bush, Adam; Borzage, Matt; Vu, Chau; Lepore, Natasha; Wood, John

    2015-12-01

    Sickle cell disease (SCD) is a hereditary blood disorder in which the oxygen-carrying hemoglobin molecule in red blood cells is abnormal. It affects numerous people in the world and leads to a shorter life span, pain, anemia, serious infections and neurocognitive decline. Tract-Specific Analysis (TSA) is a statistical method to evaluate white matter alterations due to neurocognitive diseases, using diffusion tensor magnetic resonance images. Here, for the first time, TSA is used to compare 11 major brain white matter (WM) tracts between SCD patients and age-matched healthy subjects. Alterations are found in the corpus callosum (CC), the cortico-spinal tract (CST), inferior fronto-occipital fasciculus (IFO), inferior longitudinal fasciculus (ILF), superior longitudinal fasciculus (SLF), and uncinated fasciculus (UNC). Based on previous studies on the neurocognitive functions of these tracts, the significant areas found in this paper might be related to several cognitive impairments and depression, both of which are observed in SCD patients.

  14. A Longitudinal Analysis of Search Engine Index Size

    DEFF Research Database (Denmark)

    Van den Bosch, Antal; Bogers, Toine; De Kunder, Maurice

    2015-01-01

    One of the determining factors of the quality of Web search engines is the size of their index. In addition to its influence on search result quality, the size of the indexed Web can also tell us something about which parts of the WWW are directly accessible to the everyday user. We propose a novel...... method of estimating the size of a Web search engine’s index by extrapolating from document frequencies of words observed in a large static corpus of Web pages. In addition, we provide a unique longitudinal perspective on the size of Google and Bing’s indexes over a nine-year period, from March 2006...... until January 2015. We find that index size estimates of these two search engines tend to vary dramatically over time, with Google generally possessing a larger index than Bing. This result raises doubts about the reliability of previous one-off estimates of the size of the indexed Web. We find...

  15. Child adiposity and maternal feeding practices: a longitudinal analysis.

    Science.gov (United States)

    Webber, Laura; Cooke, Lucy; Hill, Claire; Wardle, Jane

    2010-12-01

    Parental control has been hypothesized to cause weight gain in children by weakening self-regulatory processes. However, most studies that link control with weight have been cross-sectional, and therefore causation is uncertain. It remains possible that parental control is a response to child overweight rather than a cause. We investigated the direction of the association between parental feeding practices and children's adiposity in a longitudinal study. Three subscales of the Child Feeding Questionnaire (CFQ) that measure "pressure," "restriction," and "monitoring" were completed by 213 mothers of 7-9-y-old children as part of the Physical Exercise and Appetite in CHildren Study (PEACHES) and repeated by 113 mothers 3 y later. Baseline and follow-up anthropometric measurements [body mass index (BMI); fat mass index (FMI), and waist circumference (WC)] were made by researchers when the children were aged 7-9 y and 10-11 y. Regression analyses showed no association between any of the CFQ scales at baseline and change in child adiposity. In contrast, higher child BMI at baseline predicted a smaller decrease in follow-up CFQ "monitoring" (P = 0.003) and a larger decrease in "pressure to eat" (P = 0.04) after baseline scores were controlled for. Similar results were observed for FMI and WC, although they did not reach significance for WC. There were no significant longitudinal associations between child adiposity and the CFQ "restriction" subscale. The results were more consistent with a "child-responsive" model whereby a mother's choice of feeding practice is influenced by her child's weight status rather than her feeding practices influencing the child's weight gain.

  16. Self-Concept and Academic Achievement: A Meta-Analysis of Longitudinal Relations

    Science.gov (United States)

    Huang, Chiungjung

    2011-01-01

    The relation between self-concept and academic achievement was examined in 39 independent and longitudinal samples through the integration of meta-analysis and path analysis procedures. For relations with more than 3 independent samples, the mean observed correlations ranged from 0.20 to 0.27 between prior self-concept and subsequent academic…

  17. Cerebrospinal fluid biomarker supported diagnosis of Creutzfeldt–Jakob disease and rapid dementias: a longitudinal multicentre study over 10 years

    Science.gov (United States)

    Sanchez-Juan, Pascual; Gawinecka, Joanna; Green, Alison; Ladogana, Anna; Pocchiari, Maurizio; Sanchez-Valle, Raquel; Mitrova, Eva; Sklaviadis, Theodor; Kulczycki, Jerzy; Slivarichova, Dana; Saiz, Albert; Calero, Miguel; Knight, Richard; Aguzzi, Adriano; Laplanche, Jean-Louis; Peoc’h, Katell; Schelzke, Gabi; Karch, Andre; van Duijn, Cornelia M.; Zerr, Inga

    2012-01-01

    To date, cerebrospinal fluid analysis, particularly protein 14-3-3 testing, presents an important approach in the identification of Creutzfeldt–Jakob disease cases. However, one special point of criticism of 14-3-3 testing is the specificity in the differential diagnosis of rapid dementia. The constant observation of increased cerebrospinal fluid referrals in the national surveillance centres over the last years raises the concern of declining specificity due to higher number of cerebrospinal fluid tests performed in various neurological conditions. Within the framework of a European Community supported longitudinal multicentre study (‘cerebrospinal fluid markers’) we analysed the spectrum of rapid progressive dementia diagnoses, their potential influence on 14-3-3 specificity as well as results of other dementia markers (tau, phosphorylated tau and amyloid-β1–42) and evaluated the specificity of 14-3-3 in Creutzfeldt–Jakob disease diagnosis for the years 1998–2008. A total of 29 022 cerebrospinal fluid samples were analysed for 14-3-3 protein and other cerebrospinal fluid dementia markers in patients with rapid dementia and suspected Creutzfeldt–Jakob disease in the participating centres. In 10 731 patients a definite diagnosis could be obtained. Protein 14-3-3 specificity was analysed for Creutzfeldt–Jakob disease with respect to increasing cerebrospinal fluid tests per year and spectrum of differential diagnosis. Ring trials were performed to ensure the comparability between centres during the reported time period. Protein 14-3-3 test specificity remained high and stable in the diagnosis of Creutzfeldt–Jakob disease during the observed time period across centres (total specificity 92%; when compared with patients with definite diagnoses only: specificity 90%). However, test specificity varied with respect to differential diagnosis. A high 14-3-3 specificity was obtained in differentiation to other neurodegenerative diseases (95–97%) and non

  18. Cerebrospinal fluid biomarker supported diagnosis of Creutzfeldt-Jakob disease and rapid dementias: a longitudinal multicentre study over 10 years.

    Science.gov (United States)

    Stoeck, Katharina; Sanchez-Juan, Pascual; Gawinecka, Joanna; Green, Alison; Ladogana, Anna; Pocchiari, Maurizio; Sanchez-Valle, Raquel; Mitrova, Eva; Sklaviadis, Theodor; Kulczycki, Jerzy; Slivarichova, Dana; Saiz, Albert; Calero, Miguel; Knight, Richard; Aguzzi, Adriano; Laplanche, Jean-Louis; Peoc'h, Katell; Schelzke, Gabi; Karch, Andre; van Duijn, Cornelia M; Zerr, Inga

    2012-10-01

    To date, cerebrospinal fluid analysis, particularly protein 14-3-3 testing, presents an important approach in the identification of Creutzfeldt-Jakob disease cases. However, one special point of criticism of 14-3-3 testing is the specificity in the differential diagnosis of rapid dementia. The constant observation of increased cerebrospinal fluid referrals in the national surveillance centres over the last years raises the concern of declining specificity due to higher number of cerebrospinal fluid tests performed in various neurological conditions. Within the framework of a European Community supported longitudinal multicentre study ('cerebrospinal fluid markers') we analysed the spectrum of rapid progressive dementia diagnoses, their potential influence on 14-3-3 specificity as well as results of other dementia markers (tau, phosphorylated tau and amyloid-β(1-42)) and evaluated the specificity of 14-3-3 in Creutzfeldt-Jakob disease diagnosis for the years 1998-2008. A total of 29 022 cerebrospinal fluid samples were analysed for 14-3-3 protein and other cerebrospinal fluid dementia markers in patients with rapid dementia and suspected Creutzfeldt-Jakob disease in the participating centres. In 10 731 patients a definite diagnosis could be obtained. Protein 14-3-3 specificity was analysed for Creutzfeldt-Jakob disease with respect to increasing cerebrospinal fluid tests per year and spectrum of differential diagnosis. Ring trials were performed to ensure the comparability between centres during the reported time period. Protein 14-3-3 test specificity remained high and stable in the diagnosis of Creutzfeldt-Jakob disease during the observed time period across centres (total specificity 92%; when compared with patients with definite diagnoses only: specificity 90%). However, test specificity varied with respect to differential diagnosis. A high 14-3-3 specificity was obtained in differentiation to other neurodegenerative diseases (95-97%) and non

  19. Maximizing the Potential of Longitudinal Cohorts for Research in Neurodegenerative Diseases: A Community Perspective

    Directory of Open Access Journals (Sweden)

    Catherine J. Moody

    2017-08-01

    Full Text Available Despite a wealth of activity across the globe in the area of longitudinal population cohorts, surprisingly little information is available on the natural biomedical history of a number of age-related neurodegenerative diseases (ND, and the scope for intervention studies based on these cohorts is only just beginning to be explored. The Joint Programming Initiative on Neurodegenerative Disease Research (JPND recently developed a novel funding mechanism to rapidly mobilize scientists to address these issues from a broad, international community perspective. Ten expert Working Groups, bringing together a diverse range of community members and covering a wide ND landscape [Alzheimer's, Parkinson's, frontotemporal degeneration, amyotrophic lateral sclerosis (ALS, Lewy-body and vascular dementia] were formed to discuss and propose potential approaches to better exploiting and coordinating cohort studies. The purpose of this work is to highlight the novel funding process along with a broad overview of the guidelines and recommendations generated by the ten groups, which include investigations into multiple methodologies such as cognition/functional assessment, biomarkers and biobanking, imaging, health and social outcomes, and pre-symptomatic ND. All of these were published in reports that are now publicly available online.

  20. Composite marginal quantile regression analysis for longitudinal adolescent body mass index data.

    Science.gov (United States)

    Yang, Chi-Chuan; Chen, Yi-Hau; Chang, Hsing-Yi

    2017-09-20

    Childhood and adolescenthood overweight or obesity, which may be quantified through the body mass index (BMI), is strongly associated with adult obesity and other health problems. Motivated by the child and adolescent behaviors in long-term evolution (CABLE) study, we are interested in individual, family, and school factors associated with marginal quantiles of longitudinal adolescent BMI values. We propose a new method for composite marginal quantile regression analysis for longitudinal outcome data, which performs marginal quantile regressions at multiple quantile levels simultaneously. The proposed method extends the quantile regression coefficient modeling method introduced by Frumento and Bottai (Biometrics 2016; 72:74-84) to longitudinal data accounting suitably for the correlation structure in longitudinal observations. A goodness-of-fit test for the proposed modeling is also developed. Simulation results show that the proposed method can be much more efficient than the analysis without taking correlation into account and the analysis performing separate quantile regressions at different quantile levels. The application to the longitudinal adolescent BMI data from the CABLE study demonstrates the practical utility of our proposal. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  1. Alteration of putaminal fractional anisotropy in Parkinson's disease. A longitudinal diffusion kurtosis imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Surova, Yulia; Widner, Haakan [Lund University, Department of Clinical Sciences, Lund (Sweden); Skaane University Hospital, Department of Neurology, Lund (Sweden); Nilsson, Markus [Skaane University Hospital, Center for Medical Imaging and Physiology, Lund (Sweden); Lampinen, Bjoern [Lund University, Lund University Bioimaging Center, Lund (Sweden); Laett, Jimmy [Lund University, Department of Medical Radiation Physics, Lund (Sweden); Hall, Sara; Hansson, Oskar [Lund University, Department of Clinical Sciences, Malmoe (Sweden); Skaane University Hospital, Memory Clinic, Lund (Sweden); Westen, Danielle van [Lund University, Department of Clinical Sciences, Lund (Sweden); Lund University, Lund University Bioimaging Center, Lund (Sweden)

    2018-03-15

    In Parkinson's disease (PD), pathological microstructural changes occur that may be detected using diffusion magnetic resonance imaging (dMRI). However, there are few longitudinal studies that explore the effect of disease progression on diffusion indices. We prospectively included 76 patients with PD and 38 healthy controls (HC), all of whom underwent diffusion kurtosis imaging (DKI) as part of the prospective Swedish BioFINDER study at baseline and 2 years later. Annualized rates of change in DKI parameters, including fractional anisotropy (FA), mean diffusivity (MD), and mean kurtosis (MK), were estimated in the gray matter (GM) by placing regions of interest (ROIs) in the basal ganglia and the thalamus, and in the white matter (WM) by tract-based spatial statistics (TBSS) analysis. When adjusting for potential confounding factors (age, gender, baseline-follow-up interval, and software upgrade of MRI scanner), only a decrease in FA in the putamen of PD patients (β = - 0.248, P <.01) over 2 years was significantly different from the changes observed in HC over the same time period. This 2-year decrease in FA in the putamen in PD correlated with higher l-dopa equivalent dose at baseline (Spearman's rho =.399, P <.0001). The study indicates that in PD microstructural changes in the putamen occur selectively over a 2-year period and can be detected with DKI. (orig.)

  2. Predicting adolescent's cyberbullying behavior: A longitudinal risk analysis.

    Science.gov (United States)

    Barlett, Christopher P

    2015-06-01

    The current study used the risk factor approach to test the unique and combined influence of several possible risk factors for cyberbullying attitudes and behavior using a four-wave longitudinal design with an adolescent US sample. Participants (N = 96; average age = 15.50 years) completed measures of cyberbullying attitudes, perceptions of anonymity, cyberbullying behavior, and demographics four times throughout the academic school year. Several logistic regression equations were used to test the contribution of these possible risk factors. Results showed that (a) cyberbullying attitudes and previous cyberbullying behavior were important unique risk factors for later cyberbullying behavior, (b) anonymity and previous cyberbullying behavior were valid risk factors for later cyberbullying attitudes, and (c) the likelihood of engaging in later cyberbullying behavior increased with the addition of risk factors. Overall, results show the unique and combined influence of such risk factors for predicting later cyberbullying behavior. Results are discussed in terms of theory. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  3. Mathematical and field analysis of longitudinal reservoir infill

    Science.gov (United States)

    Ke, W. T.; Capart, H.

    2016-12-01

    In reservoirs, severe problems are caused by infilled sediment deposits. In long term, the sediment accumulation reduces the capacity of reservoir storage and flood control benefits. In the short term, the sediment deposits influence the intakes of water-supply and hydroelectricity generation. For the management of reservoir, it is important to understand the deposition process and then to predict the sedimentation in reservoir. To investigate the behaviors of sediment deposits, we propose a one-dimensional simplified theory derived by the Exner equation to predict the longitudinal sedimentation distribution in idealized reservoirs. The theory models the reservoir infill geomorphic actions for three scenarios: delta progradation, near-dam bottom deposition, and final infill. These yield three kinds of self-similar analytical solutions for the reservoir bed profiles, under different boundary conditions. Three analytical solutions are composed by error function, complementary error function, and imaginary error function, respectively. The theory is also computed by finite volume method to test the analytical solutions. The theoretical and numerical predictions are in good agreement with one-dimensional small-scale laboratory experiment. As the theory is simple to apply with analytical solutions and numerical computation, we propose some applications to simulate the long-profile evolution of field reservoirs and focus on the infill sediment deposit volume resulting the uplift of near-dam bottom elevation. These field reservoirs introduced here are Wushe Reservoir, Tsengwen Reservoir, Mudan Reservoir in Taiwan, Lago Dos Bocas in Puerto Rico, and Sakuma Dam in Japan.

  4. A longitudinal analysis of women's salivary testosterone and intrasexual competitiveness.

    Science.gov (United States)

    Hahn, Amanda C; Fisher, Claire I; Cobey, Kelly D; DeBruine, Lisa M; Jones, Benedict C

    2016-02-01

    Research on within-subject changes in women's intrasexual competitiveness has generally focused on possible relationships between women's intrasexual competitiveness and estimates of their fertility. While this approach is useful for testing hypotheses about the adaptive function of changes in women's intrasexual competitiveness, it offers little insight into the proximate mechanisms through which such changes might occur. To investigate this issue, we carried out a longitudinal study of the hormonal correlates of changes in intrasexual competitiveness in a large sample of heterosexual women (N=136). Each woman provided saliva samples and completed an intrasexual competitiveness questionnaire in five weekly test sessions. Multilevel modeling of these data revealed a significant, positive within-subject effect of testosterone on intrasexual competitiveness, indicating that women reported greater intrasexual competitiveness when testosterone was high. By contrast, there were no significant effects of estradiol, progesterone, estradiol-to-progesterone ratio, or cortisol and no significant effects of any hormones on reported relationship jealousy. This is the first study to demonstrate correlated changes in measured testosterone levels and women's reported intrasexual competitiveness, implicating testosterone in the regulation of women's intrasexual competitiveness. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  5. Intraoperative mapping of language functions: a longitudinal neurolinguistic analysis.

    Science.gov (United States)

    Ilmberger, Josef; Ruge, Maximilian; Kreth, Friedrich-Wilhelm; Briegel, Josef; Reulen, Hans-Juergen; Tonn, Joerg-Christian

    2008-10-01

    This prospective longitudinally designed study was conducted to evaluate language functions pre- and postoperatively in patients who underwent microsurgical treatment of tumors in close proximity to or within language areas and to detect those patients at risk for a postoperative aphasic disturbance. Between 1991 and 2005, 153 awake craniotomies with subsequent cortical mapping of language functions were performed in 149 patients. Language functions were assessed using a standardized test battery. Risk factors were obtained from multivariate logistic regression models. Language mapping was able to be performed in all patients, and complete tumor resection was achieved in 48.4%. Within 21 days after surgery a new language deficit (aphasic disturbance) was observed in 41 (32%) of the 128 cases without preoperative deficits. There were a total of 60 cases involving postoperative aphasic disturbances, including cases both with and without preoperative disturbances. Risk factors for postoperative aphasic disturbance were preoperative aphasia (planguage-positive sites within the tumor (planguage disturbances. A total of 17.6% of all cases demonstrated new postoperative language disturbances after 7 months. Risk factors for persistent aphasic disturbance were increased age (>40 years, planguage-relevant areas intraoperatively, even when they are located within the tumor. New postoperative deficits resolve in the majority of patients, which may be a result of cortical mapping as well as functional reorganization.

  6. A Longitudinal Analysis of Cigarette Prices in Military Retail Outlets

    Science.gov (United States)

    Haddock, Christopher Keith; Hyder, Melissa L.; Poston, Walker S. C.; Jahnke, Sara A.; Williams, Larry N.; Lando, Harry

    2014-01-01

    Objectives. We conducted a longitudinal assessment of tobacco pricing in military retail outlets, including trends within each service branch. Methods. We determined the price of a single pack of Marlboro Red cigarettes at military retail stores located in the continental United States, Alaska, and Hawaii and at their nearest Walmarts in spring 2011 and 2013 (n = 128 for pairs available at both assessments). Results. The average difference between cigarettes sold in military retail outlets and Walmarts decreased from 24.5% in 2011 to 12.5% in 2013. The decrease was partially attributable to significant price decreases at Walmarts. The largest increases in cigarette prices occurred on naval installations. Potential savings at stores on several installations remained substantial in 2013; the largest approached $6 per pack. Stores on 17 military installations decreased cigarette prices during the study period. Conclusions. Tobacco can be purchased in military retail stores at substantial savings over civilian stores. If tobacco pricing is to cease to be an incentive for use among personnel, a revised military tobacco pricing policy is needed. PMID:24524503

  7. Methotrexate in ocular manifestations of Behcet's disease: a longitudinal study up to 15 years.

    Science.gov (United States)

    Davatchi, Fereydoun; Shams, Hormoz; Shahram, Farhad; Nadji, Abdolhadi; Chams-Davatchi, Cheyda; Sadeghi Abdollahi, Bahar; Faezi, Tahereh; Akhlaghi, Massoomeh; Ashofteh, Farimah

    2013-10-01

    Ocular manifestations of Behcet's disease (BD) need aggressive treatment to prevent severe loss of vision or blindness. Cytotoxic drugs are the main therapeutic agents and the first line treatment. Methotrexate is the least toxic, used mainly for posterior uveitis. We present here the outcome of eye lesions with methotrexate and prednisolone, in a longitudinal study of up to 15 years, on 682 patients (5447 eye-years of follow-up). Methotrexate was started at 7.5-15 mg/week. Prednisolone was added at 0.5 mg/kg/daily, then adjusted as needed. (i) fulfilling the International Criteria for Behcet's Disease; and (ii) having active posterior uveitis (PU). Visual acuity (VA) was calculated on a scale of 10. Activity indexes were calculated for PU and retinal vasculitis (RV) for each eye. Total Inflammatory Activity Index (TIAI) demonstrating the inflammatory index of both eyes of the patient, and Total Adjusted Disease Activity Index (TADAI) showing both TIAI + VA were also calculated. Overall results: the mean VA improvement was 0.4 (P < 001), PU 1.2 (P < 0.001) and RV 0.6 (P < 0.001). VA improved in 46.5%, PU in 75.4%, and RV in 53.7% of eyes. TIAI improved in 74% of patients and TADAI in 69.4%. VA was aggravated in 37.2%, PU in 11.1%, and RV in 30.3% of eyes. TIAI was aggravated in 17.4% and TADAI in 21.6% of the patients. The remaining kept their baseline values. All parameters improved, PU better than RV. Improvement of VA was the least, mainly due to secondary cataracts. © 2013 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

  8. Longitudinal study of winter mortality disease in Sydney rock oysters Saccostrea glomerata.

    Science.gov (United States)

    Spiers, Zoe B; Gabor, Melinda; Fell, Shayne A; Carnegie, Ryan B; Dove, Michael; O'Connor, Wayne; Frances, Jane; Go, Jeffrey; Marsh, Ian B; Jenkins, Cheryl

    2014-07-24

    Winter mortality (WM) is a poorly studied disease affecting Sydney rock oysters Saccostrea glomerata in estuaries in New South Wales, Australia, where it can cause significant losses. WM is more severe in oysters cultured deeper in the water column and appears linked to higher salinities. Current dogma is that WM is caused by the microcell parasite Bonamia roughleyi, but evidence linking clinical signs and histopathology to molecular data identifying bonamiasis is lacking. We conducted a longitudinal study between February and November 2010 in 2 estuaries where WM has occurred (Georges and Shoalhaven Rivers). Results from molecular testing of experimental oysters for Bonamia spp. were compared to clinical disease signs and histopathology. Available environmental data from the study sites were also collated and compared. Oyster condition declined over the study period, coinciding with decreasing water temperatures, and was inversely correlated with the presence of histological lesions. While mortalities occurred in both estuaries, only oysters from the Georges River study site showed gross clinical signs and histological changes characteristic of WM (lesions were prevalent and intralesional microcell-like structures were sometimes noted). PCR testing for Bonamia spp. revealed the presence of an organism belonging to the B. exitiosa-B. roughleyi clade in some samples; however, the very low prevalence of this organism relative to histological changes and the lack of reactivity of affected oysters in subsequent in situ hybridisation experiments led us to conclude that this Bonamia sp. is not responsible for WM. Another aetiological agent and a confluence of environmental factors are a more likely explanation for the disease.

  9. Balancing work and family after childbirth: a longitudinal analysis.

    Science.gov (United States)

    Grice, Mira M; McGovern, Patricia M; Alexander, Bruce H; Ukestad, Laurie; Hellerstedt, Wendy

    2011-01-01

    in the United States, women with young children have dramatically increased their participation in the workforce, resulting in greater potential conflict between work and family roles. However, few studies have examined postpartum work-family conflict. This study examined associations between work-family conflict and women's health after childbirth. employed women, 18 years of age and older, were recruited while hospitalized for childbirth and followed for 18 months (n = 541; 66% response rate). Health outcomes were measured using the Short Form 12, version 2. Longitudinal fixed-effects models estimated the associations between work-family conflict (modeled as job and home spillover) and health. women who reported high levels of job spillover to home had mental health scores slightly, but significantly, worse than women who reported low levels of spillover (β = -1.26; SE = 0.47). Women with medium and high levels of home spillover to job also reported worse mental health (β = -0.81, SE = 0.30; and β = -1.52, SE = 0.78) relative to those with low spillover. Women who reported medium (versus low) levels of home spillover reported slightly improved physical health (β = 0.64, SE = 0.30). There was no significant association between job spillover and physical health. this study focused exclusively on employed postpartum women. Results illustrate that job and home spillover are associated with maternal mental and physical health. Findings also revealed that flexible work arrangements were associated with poorer postpartum mental health scores, which may reflect unintended consequences, such as increasing the amount of work brought home. 2011 Jacobs Institute of Women's Health. Published by Elsevier Inc.

  10. Analysis of longitudinal variations in North Pacific alkalinity

    Science.gov (United States)

    Fry, C.; Tyrrell, T.; Achterberg, E. P.

    2016-02-01

    Carbon measurements in the ocean lack the coverage of physical measurements, so approximate alkalinity is predicted where data is unavailable. Surface alkalinity in the North Pacific is poorly characterised by predictive algorithms. Understanding the processes affecting alkalinity in this area can improve the equations. We investigated the causes of regional variations in alkalinity using GLODAPv2. We tested different hypotheses for the causes of three longitudinal phenomena in surface ocean values of Alk*, a tracer of calcium carbonate cycling. These phenomena are: (a) an increase in Alk* from east to west at 50°N, (b) an increase in Alk* from west to east at 30°N, and (c) a lack of a strong increase in Alk* from west to east in the equatorial upwelling area. We found that the most likely cause of higher Alk* on the western side of the subpolar North Pacific (at 50°N) is that denser isopycnals with higher Alk* lie at shallower depths on the western side than the eastern side. At 30°N, the main cause of higher Alk* on the eastern side of the basin is upwelling along the continental shelf of southwestern North America. Along the equator, our analyses suggest that the absence of a strong east-west trend is because the more intense upwelling on the eastern side of the basin does not, under normal conditions, lead to strong elevation of Alk*. However, surface Alk* is more strongly elevated in the eastern Equatorial Pacific during negative phases of the El-Nino-Southern Oscillation, probably because the upwelled water comes from greater depth at these times.

  11. A longitudinal analysis of alcohol outlet density and domestic violence.

    Science.gov (United States)

    Livingston, Michael

    2011-05-01

    A small number of studies have identified a positive relationship between alcohol outlet density and domestic violence. These studies have all been based on cross-sectional data and have been limited to the assessment of ecological correlations between outlet density and domestic violence rates. This study provides the first longitudinal examination of this relationship. Cross-sectional time-series using aggregated data from small areas. The relationships between alcohol outlet density and domestic violence were assessed over time using a fixed-effects model. Controls for the spatial autocorrelation of the data were included in the model. The study uses data for 186 postcodes from within the metropolitan area of Melbourne, Australia for the years 1996 to 2005. Alcohol outlet density measures for three different types of outlets (hotel/pub, packaged liquor, on-premise) were derived from liquor licensing records and domestic violence rates were calculated from police-recorded crime data, based on the victim's postcode. Alcohol outlet density was associated significantly with rates of domestic violence, over time. All three licence categories were positively associated with domestic violence rates, with small effects for general (pub) and on-premise licences and a large effect for packaged liquor licences. In Melbourne, the density of liquor licences is positively associated with rates of domestic violence over time. The effects were particularly large for packaged liquor outlets, suggesting a need for licensing policies that pay more attention to o off-premise alcohol availability. © 2011 The Authors, Addiction © 2011 Society for the Study of Addiction.

  12. Multi-modal neuroimaging in premanifest and early Huntington's disease: 18 month longitudinal data from the IMAGE-HD study.

    Science.gov (United States)

    Domínguez D, Juan F; Egan, Gary F; Gray, Marcus A; Poudel, Govinda R; Churchyard, Andrew; Chua, Phyllis; Stout, Julie C; Georgiou-Karistianis, Nellie

    2013-01-01

    IMAGE-HD is an Australian based multi-modal longitudinal magnetic resonance imaging (MRI) study in premanifest and early symptomatic Huntington's disease (pre-HD and symp-HD, respectively). In this investigation we sought to determine the sensitivity of imaging methods to detect macrostructural (volume) and microstructural (diffusivity) longitudinal change in HD. We used a 3T MRI scanner to acquire T1 and diffusion weighted images at baseline and 18 months in 31 pre-HD, 31 symp-HD and 29 controls. Volume was measured across the whole brain, and volume and diffusion measures were ascertained for caudate and putamen. We observed a range of significant volumetric and, for the first time, diffusion changes over 18 months in both pre-HD and symp-HD, relative to controls, detectable at the brain-wide level (volume change in grey and white matter) and in caudate and putamen (volume and diffusivity change). Importantly, longitudinal volume change in the caudate was the only measure that discriminated between groups across all stages of disease: far from diagnosis (>15 years), close to diagnosis (fractional anisotropy, FA), only longitudinal FA change was sensitive to group differences, but only after diagnosis. These findings further confirm caudate atrophy as one of the most sensitive and early biomarkers of neurodegeneration in HD. They also highlight that different tissue properties have varying schedules in their ability to discriminate between groups along disease progression and may therefore inform biomarker selection for future therapeutic interventions.

  13. A meta-analysis of cerebrovascular disease and hyperhomocysteinaemia

    DEFF Research Database (Denmark)

    Nielsen, G M; Tvedegaard, K C; Andersen, Niels Trolle

    2000-01-01

    Hyperhomocysteinaemia has been identified as a risk factor for stroke and cerebrovascular disease in several studies. To evaluate the evidence we performed a meta-analysis. We found 21 studies searching Medline from 1966-July 1999 using the key words homocysteine, homocystine and cerebrovascular...... was used. The reports on 8 cross-sectional and 4 longitudinal studies gave data on the mean and standard deviations of plasma or serum homocysteine for both cases and controls, and these studies were included in the meta-analysis. The results of the 5 excluded studies all pointed to a positive relationship...

  14. Longitudinal trends and subgroup analysis in publication patterns for preclinical data of newly approved drugs.

    Science.gov (United States)

    Köster, Ursula; Nolte, Ingo; Michel, Martin C

    2016-02-01

    Having observed a large variation in the number and type of original preclinical publications for newly registered drugs, we have explored whether longitudinal trends and/or factors specific for certain drugs or their manufacturers may explain such variation. Our analysis is based on 1954 articles related to 170 newly approved drugs. The number of preclinical publications per compound declined from a median of 10.5 in 1991 to 3 in 2011. A similar trend was observed for the number of in vivo studies in general, but not in the subset of in vivo studies in animal models of disease. The percentage of compounds with studies using isolated human cells or cell lines almost doubled over time from 37 to 72%. Number of publications did not exhibit major differences between compounds intended for human versus veterinary use, therapeutic areas, small molecules versus biologicals, or innovator versus follow-up compounds; however, some companies may publish fewer studies per compound than others. However, there were qualitative differences in the types of models being used depending on the therapeutic area; specifically, compounds for use in oncology very often used isolated cells and cell lines, often from human origin. We conclude that the large variation in number and type of reported preclinical data is not easily explained. We propose that pharmaceutical companies should consistently provide a comprehensive documentation of the preclinical data they generate as part of their development programs in the public domain to enable a better understanding of the drugs they intend to market.

  15. The influence of subjective aging on health and longevity: A meta-analysis of longitudinal data

    NARCIS (Netherlands)

    Westerhof, Gerben Johan; Miche, M.; Brothers, A.F.; Barrett, A.E.; Diehl, M.; Montepare, J.M.; Wahl, H.-W.; Wurm, S.

    2014-01-01

    Evidence is accumulating on the effects of subjective aging—that is, how individuals perceive their own aging process—on health and survival in later life. The goal of this article is to synthesize findings of existing longitudinal studies through a meta-analysis. A systematic search in PsycInfo,

  16. A Service Member's Self in Transition : A Longitudinal Case Study Analysis

    NARCIS (Netherlands)

    Grimell, Jan

    2017-01-01

    Adopting a narrative approach with a dialogical framework, a longitudinal case study is presented that describes a service member's self in transition from active service into the civilian population. An analysis and interpretation of the case study leads to the hypothesis that if a dominant

  17. Signs over time: Statistical and visual analysis of a longitudinal signed network

    NARCIS (Netherlands)

    de Nooy, W.

    2008-01-01

    This paper presents the design and results of a statistical and visual analysis of a dynamic signed network. In addition to prevalent approaches to longitudinal networks, which analyze series of cross-sectional data, this paper focuses on network data measured in continuous time in order to explain

  18. The State of PR Graduate Curriculum as We Know It: A Longitudinal Analysis

    Science.gov (United States)

    Briones, Rowena L.; Toth, Elizabeth L.

    2013-01-01

    This longitudinal content analysis study uses the Commission on Public Relations Education's 2006 report as a benchmark to determine whether master's education in public relations has evolved over the past decade. Findings show a lack of uniformity across the 75 programs studied. In addition, there is a lack of adherence to the Commission on…

  19. Profiles of Intrinsic and Extrinsic Motivations in Elementary School: A Longitudinal Analysis

    Science.gov (United States)

    Corpus, Jennifer Henderlong; Wormington, Stephanie V.

    2014-01-01

    The authors used a person-centered, longitudinal approach to identify and evaluate naturally occurring combinations of intrinsic and extrinsic motivations among 490 third- through fifth-grade students. Cluster analysis revealed 3 groups, characterized by high levels of both motivations ("high quantity"): high intrinsic motivation but low…

  20. Decreasing Sports Activity with Increasing Age? Findings from a 20-Year Longitudinal and Cohort Sequence Analysis

    Science.gov (United States)

    Breuer, Christoph; Wicker, Pamela

    2009-01-01

    According to cross-sectional studies in sport science literature, decreasing sports activity with increasing age is generally assumed. In this paper, the validity of this assumption is checked by applying more effective methods of analysis, such as longitudinal and cohort sequence analyses. With the help of 20 years' worth of data records from the…

  1. Indexing Combined with Statistical Deflation as a Tool for Analysis of Longitudinal Data.

    Science.gov (United States)

    Babcock, Judith A.

    Indexing is a tool that can be used with longitudinal, quantitative data for analysis of relative changes and for comparisons of changes among items. For greater accuracy, raw financial data should be deflated into constant dollars prior to indexing. This paper demonstrates the procedures for indexing, statistical deflation, and the use of…

  2. Statistical analysis of longitudinal quality of life data with missing measurements

    NARCIS (Netherlands)

    Zwinderman, A. H.

    1992-01-01

    The statistical analysis of longitudinal quality of life data in the presence of missing data is discussed. In cancer trials missing data are generated due to the fact that patients die, drop out, or are censored. These missing data are problematic in the monitoring of the quality of life during the

  3. An approximate marginal logistic distribution for the analysis of longitudinal ordinal data

    NARCIS (Netherlands)

    Nooraee, Nazanin; Abegaz, Fentaw; Ormel, Johan; Wit, Ernst; van den Heuvel, Edwin R

    Subject-specific and marginal models have been developed for the analysis of longitudinal ordinal data. Subject-specific models often lack a population-average interpretation of the model parameters due to the conditional formulation of random intercepts and slopes. Marginal models frequently lack

  4. Friendship Quality and School Achievement: A Longitudinal Analysis during Primary School

    Science.gov (United States)

    Zucchetti, Giulia; Candela, Filippo; Sacconi, Beatrice; Rabaglietti, Emanuela

    2015-01-01

    This study examined the longitudinal relationship between friendship quality (positive and negative) and school achievement among 228 school-age children (51% girls, M = 8.09, SD = 0.41). A three-wave cross-lagged analysis was used to determine the direction of influence between these domains across school years. Findings revealed that: (a) school…

  5. Stability and Change in Work Values: A Meta-Analysis of Longitudinal Studies

    Science.gov (United States)

    Jin, Jing; Rounds, James

    2012-01-01

    A meta-analysis of longitudinal studies was conducted to investigate stability and change in work values across the life span. Both rank-order stability and mean-level change were investigated using an integrative classification for intrinsic, extrinsic, social and status work values (Ross, Schwartz, & Surkis, 1999). Results of rank-order…

  6. Social Capital, Self-Esteem, and Use of Online Social Network Sites: A Longitudinal Analysis

    Science.gov (United States)

    Steinfield, Charles; Ellison, Nicole B.; Lampe, Cliff

    2008-01-01

    A longitudinal analysis of panel data from users of a popular online social network site, Facebook, investigated the relationship between intensity of Facebook use, measures of psychological well-being, and bridging social capital. Two surveys conducted a year apart at a large U.S. university, complemented with in-depth interviews with 18 Facebook…

  7. Regulation and dysregulation of esophageal peristalsis by the integrated function of circular and longitudinal muscle layers in health and disease.

    Science.gov (United States)

    Mittal, Ravinder K

    2016-09-01

    Muscularis propria throughout the entire gastrointestinal tract including the esophagus is comprised of circular and longitudinal muscle layers. Based on the studies conducted in the colon and the small intestine, for more than a century, it has been debated whether the two muscle layers contract synchronously or reciprocally during the ascending contraction and descending relaxation of the peristaltic reflex. Recent studies in the esophagus and colon prove that the two muscle layers indeed contract and relax together in almost perfect synchrony during ascending contraction and descending relaxation of the peristaltic reflex, respectively. Studies in patients with various types of esophageal motor disorders reveal temporal disassociation between the circular and longitudinal muscle layers. We suggest that the discoordination between the two muscle layers plays a role in the genesis of esophageal symptoms, i.e., dysphagia and esophageal pain. Certain pathologies may selectively target one and not the other muscle layer, e.g., in eosinophilic esophagitis there is a selective dysfunction of the longitudinal muscle layer. In achalasia esophagus, swallows are accompanied by the strong contraction of the longitudinal muscle without circular muscle contraction. The possibility that the discoordination between two muscle layers plays a role in the genesis of esophageal symptoms, i.e., dysphagia and esophageal pain are discussed. The purpose of this review is to summarize the regulation and dysregulation of peristalsis by the coordinated and discoordinated function of circular and longitudinal muscle layers in health and diseased states.

  8. Caregiver perception of apathy in persons with mild cognitive impairment or Alzheimer's disease: a longitudinal study.

    Science.gov (United States)

    Pfeifer, Livia; Horn, Andrea B; Maercker, Andreas; Forstmeier, Simon

    2017-05-01

    Discrepancy between self- and caregiver apathy ratings was examined longitudinally for persons with mild cognitive impairment or Alzheimer's disease. Particular focus was on the distinction between the positive and negative caregiver bias and its predictive value for a clinical diagnosis of apathy. Apathy rating discrepancy was based on the apathy evaluation scale. Dyads were categorized depending on whether the caregiver reported fewer deficits (positive caregiver bias) or more deficits (negative caregiver bias) than the cognitively impaired person did. Caregiver ratings and rating discrepancy showed a significant increase from baseline to follow-up. By contrast, self- and clinician ratings showed no change across the two time points. Ratings with a negative caregiver bias remained stable, while those with a positive caregiver bias showed a significant increase in the caregiver ratings but also a significant decrease in the self-ratings. A negative caregiver bias at baseline was significantly related to greater likelihood of having clinical apathy at follow-up, adjusted for an array of control variables. Positive and negative caregiver bias should be distinguished, as they seem to reflect distinct dyadic processes and are relevant for clinical outcome. Furthermore, negative rating discrepancies can be considered a risk factor for developing apathy.

  9. Disease management programs for patients with asthma in Germany: a longitudinal population-based study.

    Science.gov (United States)

    Mehring, Michael; Donnachie, Ewan; Mutschler, Robert; Hofmann, Frank; Keller, Manfred; Schneider, Antonius

    2013-07-01

    The primary aim of the disease management program (DMP) for patients with asthma is to improve health outcomes and to reduce costs. Five years after its introduction in Germany, no consensus has yet been reached as to whether DMP has been effective in reaching these goals. To evaluate the DMP for asthma in Bavaria using routinely collected subject medical records. A longitudinal population-based study encompassing over 100,000 DMP participants between 2006 (when the program began) and 2010. The prescription rate of oral corticosteroids dropped from 15.7% in 2006 to 13.6% in 2007, and again from 7.5% in 2008 to 5.9% in 2010 (P management education increased from 4.4% to 23.4% (P management. The proportion of subjects requiring hospitalization decreased. Our results suggest that the German DMP for asthma has been effective in enhancing the quality of care in regard to an improved symptom frequency, adherence to guidelines, pharmacotherapy, and hospitalization.

  10. Adolescence and Later Life Disease Burden: Quantifying the Contribution of Adolescent Tobacco Initiation From Longitudinal Cohorts.

    Science.gov (United States)

    Viner, Russell M; Hargreaves, Dougal S; Motta, Janaina Vieira Dos Santos; Horta, Bernardo; Mokdad, Ali H; Patton, George

    2017-08-01

    Adolescence is a time of initiation of behaviors leading to noncommunicable diseases (NCDs). We use tobacco to illustrate a novel method for assessing the contribution of adolescence to later burden. Data on initiation of regular smoking during adolescence (10-19 years) and current adult smoking were obtained from the 1958 British Birth Cohort, the U.S. National Longitudinal Study of Adolescent Health (Add Health), the Pelotas 1982 Birth Cohort, and the Victorian Adolescent Health Cohort Study. We estimated an "adolescent attributable fraction" (AAF) by calculating the proportion of persisting adult daily smoking initiated 155 countries using contemporary surveillance data. In the 1958 British Birth Cohort, 81.6% of daily smokers at age 50 years initiated adolescent initiation. The adjusted AAF was 69.1. Proportions of smokers initiating Adolescent Health Cohort Study; and 70.9%, 5.8%, and 56.9% in Pelotas males and 89.9%, 6.4%, and 75.9% in females. Initiation adolescent smoking initiation to adult smoking burden is high, suggesting a need to formulate and implement effective actions to reduce smoking initiation in adolescents. Similar trends in other NCD risks suggest that adolescents will be central to future efforts to control NCDs. Copyright © 2017 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  11. The Exploding Spark: Workplace Violence in an Infectious Disease Hospital—A Longitudinal Study

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    Nicola Magnavita

    2013-01-01

    Full Text Available Objectives. Workplace violence (WV is an important occupational hazard for healthcare workers (HCWs. Methods. A longitudinal study was carried out on HCWs from an infectious disease hospital. Work-related stress, anxiety, and depression were measured at baseline in 2003, and they were reassessed in 2005, along with the assaults that occurred in the previous year. Results. One-year prevalences of 6.2% and 13.9% were reported for physical and verbal aggressions, respectively. Perpetrators were mainly patients. The professional groups most frequently attacked were physicians, followed by nurses. Workers with job strain at baseline had a significant risk of being subject to aggression (OR 7.7; CI 95%, 3.3–17.9 in the following year. The relationship between job strain and subsequent WV remained significant even after correction for anxiety, depression, and other confounders. Conversely, experiencing WV was associated with a high risk of job strain and effort-reward imbalance in the following year. The final levels of anxiety and depression were predicted using regression models that included physical aggression among predictive variables. Conclusions. WV is the spark that sets off a problematic work situation. Effective prevention of WV can only be achieved within the framework of an overall improvement in the quality of work.

  12. Association analysis of whole genome sequencing data accounting for longitudinal and family designs.

    Science.gov (United States)

    Hu, Yijuan; Hui, Qin; Sun, Yan V

    2014-01-01

    Using the whole genome sequencing data and the simulated longitudinal phenotypes for 849 pedigree-based individuals from Genetic Analysis Workshop 18, we investigated various approaches to detecting the association of rare and common variants with blood pressure traits. We compared three strategies for longitudinal data: (a) using the baseline measurement only, (b) using the average from multiple visits, and (c) using all individual measurements. We also compared the power of using all of the pedigree-based data and the unrelated subset. The analyses were performed without knowledge of the underlying simulating model.

  13. Longitudinal AddiQoL scores may identify higher risk for adrenal crises in Addison's disease.

    Science.gov (United States)

    Meyer, Gesine; Koch, Maike; Herrmann, Eva; Bojunga, Jörg; Badenhoop, Klaus

    2018-05-01

    Several studies have shown a reduced quality of life (QoL) in patients with Addison's disease (AD), but investigations of QoL over a long-term course are lacking. Adrenal crises (AC) are life-threatening complications in AD. The purpose of this prospective study was to test whether the repeated use of QoL-questionnaires can detect prodromal periods of an AC. 110 patients with AD were asked to complete the disease specific-QoL questionnaire AddiQoL and a short questionnaire about adverse events once monthly over a period of ten months. AC was defined if at least two of the following symptoms were reported: (a) hypotension, (b) nausea or vomiting, (c) severe fatigue, (d) documented hyponatremia, hyperkalemia, or hypoglycemia, and subsequent parenteral glucocorticoid administration was carried out. Prevalence of AC was 10.9/100 patient years. AddiQoL scores in patients with AC showed a trend (p = 0,08) to a wider fluctuation over time. Subjective precrises not meeting the criteria for AC were reported by 31 patients who had significantly lower AddiQoL scores (p = 0,018). These are the first data showing the course of QoL during a period of ten months in patients with AD. Incidence of AC exceeds previous data. Our data show, that subjective precrises in AD associate with lower QoL. AC, as well as precrises affect intraindividual AddiQol-scores over time with a trend to a stronger fluctuation. Longitudinal AddiQol scores and self-reporting of precrises via patient diaries are additional clinical tools to identify higher risk for critical events.

  14. Longitudinal CSF biomarkers in patients with early Parkinson disease and healthy controls.

    Science.gov (United States)

    Mollenhauer, Brit; Caspell-Garcia, Chelsea J; Coffey, Christopher S; Taylor, Peggy; Shaw, Leslie M; Trojanowski, John Q; Singleton, Andy; Frasier, Mark; Marek, Kenneth; Galasko, Douglas

    2017-11-07

    To analyze longitudinal levels of CSF biomarkers in drug-naive patients with Parkinson disease (PD) and healthy controls (HC), examine the extent to which these biomarker changes relate to clinical measures of PD, and identify what may influence them. CSF α-synuclein (α-syn), total and phosphorylated tau (t- and p-tau), and β-amyloid 1-42 (Aβ42) were measured at baseline and 6 and 12 months in 173 patients with PD and 112 matched HC in the international multicenter Parkinson's Progression Marker Initiative. Baseline clinical and demographic variables, PD medications, neuroimaging, and genetic variables were evaluated as potential predictors of CSF biomarker changes. CSF biomarkers were stable over 6 and 12 months, and there was a small but significant increase in CSF Aβ42 in both patients with patients with PD and HC from baseline to 12 months. The t-tau remained stable. The p-tau increased marginally more in patients with PD than in HC. α-syn remained relatively stable in patients with PD and HC. Ratios of p-tau/t-tau increased, while t-tau/Aβ42 decreased over 12 months in patients with PD. CSF biomarker changes did not correlate with changes in Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale motor scores or dopamine imaging. CSF α-syn levels at 12 months were lower in patients with PD treated with dopamine replacement therapy, especially dopamine agonists. These core CSF biomarkers remained stable over 6 and 12 months in patients with early PD and HC. PD medication use may influence CSF α-syn. Novel biomarkers are needed to better profile progressive neurodegeneration in PD. Copyright © 2017 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.

  15. FreeWalker: a smart insole for longitudinal gait analysis.

    Science.gov (United States)

    Wang, Baitong; Rajput, Kuldeep Singh; Tam, Wing-Kin; Tung, Anthony K H; Yang, Zhi

    2015-08-01

    Gait analysis is an important diagnostic measure to investigate the pattern of walking. Traditional gait analysis is generally carried out in a gait lab, with equipped force and body tracking sensors, which needs a trained medical professional to interpret the results. This procedure is tedious, expensive, and unreliable and makes it difficult to track the progress across multiple visits. In this paper, we present a smart insole called FreeWalker, which provides quantitative gait analysis outside the confinement of traditional lab, at low- cost. The insole consists of eight pressure sensors and two motion tracking sensors, i.e. 3-axis accelerometer and 3-axis gyroscope. This enables measurement of under-foot pressure distribution and motion sequences in real-time. The insole is enabled with onboard SD card as well as wireless data transmission, which help in continuous gait-cycle analysis. The data is then sent to a gateway, for analysis and interpretation of data, using a user interface where gait features are graphically displayed. We also present validation result of a subject's left foot, who was asked to perform a specific task. Experiment results show that we could achieve a data-sampling rate of over 1 KHz, transmitting data up to a distance of 20 meter and maintain a battery life of around 24 hours. Taking advantage of these features, FreeWalker can be used in various applications, like medical diagnosis, rehabilitation, sports and entertainment.

  16. Life satisfaction and longitudinal changes in physical activity, diabetes and obesity among patients with cardiovascular diseases.

    Science.gov (United States)

    Baumann, Michèle; Tchicaya, Anastase; Lorentz, Nathalie; Le Bihan, Etienne

    2017-12-02

    Patients with cardiovascular disease who underwent coronary angiography at the National Institute of Cardiac Surgery and Cardiological Intervention (INCCI) in Luxembourg were surveyed for cardiovascular risk factors (CVRF) (hypertension, hypercholesterolemia, diabetes, obesity, physical inactivity, tobacco consumption). In 2013/14, their life satisfaction (LS) was also assessed. Our aim was to analyse the relationships between LS on one hand and longitudinal changes in CVRF between 2008/09 and 2013/14 and socioeconomic factors on the other. 1289 patients completed a self-administered questionnaire. Life Satisfaction, originally recorded on a 1 to 10 scale of complete satisfaction was dichotomized into two groups: ≤ 7 and. >7. We then performed logistic multiple regressions. The event on which the probability was modelled, was LS > 7. Data were adjusted on age, sex and income. Longitudinal changes in CVRF were assessed by their presence or absence in 2008/09 and 2013/14 (categories: 'no-no'; 'no-yes'; 'yes-no'; 'yes-yes'). Physical activity in 2008/09 and 2013/14 was associated with a lower LS (OR = 0.469). The same pattern was observed for obesity and physical inactivity: lower LS was related to the presence of these risks (yes-yes; no-yes) in 2013/14 (mean OR for obesity and physical inactivity in 2013/14: 0.587 and 0.485 respectively), whereas their presence or absence in 2008/09 was not related to LS. Finally, patients who suffered from diabetes in 2008 were more likely to experience a decline in LS, particularly if their diabetes was less severe in 2013/14 (OR = 0.462). The lowest LS was observed when obesity or physical inactivity was present in 2013/14, newly or otherwise. The same trend was seen in diabetes among patients who had it in 2008/9, but were less severely affected in 2013/14. In secondary prevention, CVD-related upheavals could be minimised if professionals and patients became 'Partners in Healthcare' to better adhere to healthy

  17. Effects of prediabetes mellitus alone or plus hypertension on subsequent occurrence of cardiovascular disease and diabetes mellitus: longitudinal study.

    Science.gov (United States)

    Qiu, Miaoyan; Shen, Weili; Song, Xiaomin; Ju, Liping; Tong, Wenxin; Wang, Haiyan; Zheng, Sheng; Jin, Yan; Wu, Yixin; Wang, Weiqing; Tian, Jingyan

    2015-03-01

    Whether prediabetes mellitus alone or combined with other disorders means a higher risk for cardiovascular disease (CVD) is still controversial. This study aimed to investigate the association between prediabetes mellitus and CVD and diabetes mellitus and to explore whether prediabetes mellitus alone or combined with other syndromes, such as hypertension, could promote CVD risks significantly. This longitudinal population-based study of 1609 residents from Shanghai in Southern China was conducted between 2002 and 2014. Participants with a history of CVD at baseline were excluded from analysis. Multivariate log-binomial regression models were used to adjust possible coexisting factors. Incidence of CVD during follow-up was 10.1%. After adjusting for age, sex, and other factors, the association between prediabetes mellitus and CVD was not observed. When hypertension was incorporated in stratifying factors, adjusted CVD risk was elevated significantly (odds ratio, 2.41; 95% confidence interval, 1.25-4.64) in prediabetes mellitus and hypertension combined group, and coexistence of diabetes mellitus and hypertension made CVD risk highly significantly increased, reaching 3.43-fold higher than the reference group. Blood glucose level within prediabetic range is significantly associated with elevated risks for diabetes mellitus after multivariable adjustment, but only when it is concurrent with other disorders, such as hypertension, it will significantly increase CVD risk. © 2015 American Heart Association, Inc.

  18. LONGITUDINAL EVALUATION OF ACADEMIC DEPARTMENTS USING DATA ENVELOPMENT ANALYSIS

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    Rodrigo Meleu das Neves

    2016-11-01

    Full Text Available Corresponding to the smallest structure in a University for educational-academic, administrative and personnel allocation purposes, the academic department is currently a sui generis entity. The research proposes a temporal analysis of the relative efficiency of 93 academic departments at Federal University of Rio Grande do Sul (UFRGS over the period of 1998 through 2007, using the mathematical modeling technique called data envelopment analysis, as well as indicators equally related to education, research and extension. Among other conclusions, it can be observed that adding a professor to the faculty does not proportionally impact productivity; actually, the synergy may bring even better results. Likewise, removing a professor may not proportionally decrease department output. Furthermore, the research traces a relationship between the results obtained in the replicated model and the model practiced to establish a criteria of faculty position distribution: the department index. The authors present their findings by means of a mixed method technique. The homogeneity of those departments more dedicated to research and the increasing investment on the part of UFRGS in extension evidence the contrast between models, even considering that reorganizations in the system employed for this analysis may leave room for questioning.

  19. Metastatic spread pattern after curative colorectal cancer surgery. A retrospective, longitudinal analysis.

    Science.gov (United States)

    Augestad, K M; Bakaki, P M; Rose, J; Crawshaw, B P; Lindsetmo, R O; Dørum, L M; Koroukian, S M; Delaney, C P

    2015-10-01

    The most common sites of colorectal cancer (CRC) recurrence are the local tissues, liver or lungs. The objective was to identify risk factors associated with the primary CRC tumor and cancer recurrence in these anatomical sites. Retrospective, longitudinal analyses of data on CRC survivors. Multivariable Cox regression analysis was performed to examine the association between possible cofounders with recurrence to various anatomical sites. Data for 10,398CRC survivors (tumor location right colon=3870, left colon=2898, high rectum=2569, low rectum=1061) were analyzed; follow up time was up to five years. Mean age at curative surgery was 71.5 (SD 11.8) years, 20.2% received radio-chemotherapy, stage T3 (64.4%) and N0 (65.1%) were most common. Overall 1632 (15.7%) had cancer recurrence (Isolated liver n=412, 3,8%;  isolated lung n=252, 2,4%; isolated local n=223, 2.1%). Risk factors associated with recurrent CRC were identified, i.e. isolated liver metastases (male: Adjusted Hazard Ratio (AHR) 1,45; colon left: AHR 1,63; N2 disease: AHR 3,35; T2 disease: AHR 2,82), isolated lung metastases (colon left: AHR 1,53; rectum high: AHR 2,48; rectum low: AHR 2,65; N2 disease 3,76), and local recurrence (glands examined<12: AHR 1,51; CRM <3mm: AHR 1,60; rectum high: AHR 2,15; N2 disease: AHR 2,58) (all p values <0001). Our study finds that the site of the primary CRC tumor is associated with location of subsequent metastasis. Left sided colon cancers have increased risk of metastatic spread to the liver, whereas rectal cancers have increased risk of local recurrence and metastatic spread to the lungs. These results, in combination with other risk factors for CRC recurrence, should be taken into consideration when designing risk adapted post-treatment CRC surveillance programs. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Association between earthquake events and cholera outbreaks: a cross-country 15-year longitudinal analysis.

    Science.gov (United States)

    Sumner, Steven A; Turner, Elizabeth L; Thielman, Nathan M

    2013-12-01

    Large earthquakes can cause population displacement, critical sanitation infrastructure damage, and increased threats to water resources, potentially predisposing populations to waterborne disease epidemics such as cholera. Problem The risk of cholera outbreaks after earthquake disasters remains uncertain. A cross-country analysis of World Health Organization (WHO) cholera data that would contribute to this discussion has yet to be published. A cross-country longitudinal analysis was conducted among 63 low- and middle-income countries from 1995-2009. The association between earthquake disasters of various effect sizes and a relative spike in cholera rates for a given country was assessed utilizing fixed-effects logistic regression and adjusting for gross domestic product per capita, water and sanitation level, flooding events, percent urbanization, and under-five child mortality. Also, the association between large earthquakes and cholera rate increases of various degrees was assessed. Forty-eight of the 63 countries had at least one year with reported cholera infections during the 15-year study period. Thirty-six of these 48 countries had at least one earthquake disaster. In adjusted analyses, country-years with ≥10,000 persons affected by an earthquake had 2.26 times increased odds (95 CI, 0.89-5.72, P = .08) of having a greater than average cholera rate that year compared to country-years having earthquake. The association between large earthquake disasters and cholera infections appeared to weaken as higher levels of cholera rate increases were tested. A trend of increased risk of greater than average cholera rates when more people were affected by an earthquake in a country-year was noted. However these findings did not reach statistical significance at traditional levels and may be due to chance. Frequent large-scale cholera outbreaks after earthquake disasters appeared to be relatively uncommon.

  1. Comparison of CTT and Rasch-based approaches for the analysis of longitudinal Patient Reported Outcomes.

    Science.gov (United States)

    Blanchin, Myriam; Hardouin, Jean-Benoit; Le Neel, Tanguy; Kubis, Gildas; Blanchard, Claire; Mirallié, Eric; Sébille, Véronique

    2011-04-15

    Health sciences frequently deal with Patient Reported Outcomes (PRO) data for the evaluation of concepts, in particular health-related quality of life, which cannot be directly measured and are often called latent variables. Two approaches are commonly used for the analysis of such data: Classical Test Theory (CTT) and Item Response Theory (IRT). Longitudinal data are often collected to analyze the evolution of an outcome over time. The most adequate strategy to analyze longitudinal latent variables, which can be either based on CTT or IRT models, remains to be identified. This strategy must take into account the latent characteristic of what PROs are intended to measure as well as the specificity of longitudinal designs. A simple and widely used IRT model is the Rasch model. The purpose of our study was to compare CTT and Rasch-based approaches to analyze longitudinal PRO data regarding type I error, power, and time effect estimation bias. Four methods were compared: the Score and Mixed models (SM) method based on the CTT approach, the Rasch and Mixed models (RM), the Plausible Values (PV), and the Longitudinal Rasch model (LRM) methods all based on the Rasch model. All methods have shown comparable results in terms of type I error, all close to 5 per cent. LRM and SM methods presented comparable power and unbiased time effect estimations, whereas RM and PV methods showed low power and biased time effect estimations. This suggests that RM and PV methods should be avoided to analyze longitudinal latent variables. Copyright © 2010 John Wiley & Sons, Ltd.

  2. Stressors, resources, and distress among homeless persons: a longitudinal analysis.

    Science.gov (United States)

    Wong, Y L; Piliavin, I

    2001-04-01

    Relations among stressors, resources, and psychological distress were examined using two waves of data obtained from a probability sample of homeless persons (N = 430) residing in a large, demographically diverse county in North California. The focus of research was to examine whether and how social resources and housing resources directly affect distress and mediate the impact of stress factors on depressive symptoms. Path analysis results revealed that levels of psychological distress were responsive to change in objective housing circumstances, with the attainment of domicile status being associated with fewer distress symptoms. Our findings, however, indicated only modest effects of social resources on psychological distress through direct effects and mediating effects of life stressors on distress. Overall, the study suggests that the relationships among stressors, resources, and distress for homeless persons may be understood within the same analytical framework for the general population.

  3. Longitudinal Assessment of Tau Pathology in Patients with Alzheimer's Disease Using [18F]THK-5117 Positron Emission Tomography.

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    Aiko Ishiki

    Full Text Available The formation of neurofibrillary tangles is believed to contribute to the neurodegeneration observed in Alzheimer's disease (AD. Postmortem studies have shown strong associations between the neurofibrillary pathology and both neuronal loss and the severity of cognitive impairment. However, the temporal changes in the neurofibrillary pathology and its association with the progression of the disease are not well understood. Tau positron emission tomography (PET imaging is expected to be useful for the longitudinal assessment of neurofibrillary pathology in the living brain. Here, we performed a longitudinal PET study using the tau-selective PET tracer [18F]THK-5117 in patients with AD and in healthy control subjects. Annual changes in [18F]THK-5117 binding were significantly elevated in the middle and inferior temporal gyri and in the fusiform gyrus of patients with AD. Compared to patients with mild AD, patients with moderate AD showed greater changes in the tau load that were more widely distributed across the cortical regions. Furthermore, a significant correlation was observed between the annual changes in cognitive decline and regional [18F]THK-5117 binding. These results suggest that the cognitive decline observed in patients with AD is attributable to the progression of neurofibrillary pathology. Longitudinal assessment of tau pathology will contribute to the assessment of disease progression and treatment efficacy.

  4. Longitudinal prediction of sexually transmitted diseases among adolescents: results from a national survey.

    Science.gov (United States)

    Crosby, R; Leichliter, J S; Brackbill, R

    2000-05-01

    Although adolescent use of condoms has been increasing, incidence of sexually transmitted diseases (STDs) among young people remains high. To identify adolescent behavioral risk factors for acquiring STDs, this study assessed adolescent self-reports of acquired chlamydia, gonorrhea, syphilis, and trichomoniasis within 1 year after a baseline interview. We used data from the National Longitudinal Survey of Adolescent Health for this study. Data were collected in the homes of survey respondents, using audio-computer-assisted self-interview (audio-CASI) technology and interviews. Participants were enrolled in grades 7-11 from 134 U.S. schools. A cohort of 4593 sexually experienced adolescents was followed for 1 year. We conducted separate analyses for both genders. About 3.1% of the male adolescents and nearly 4.7% of the female adolescents reported having had at least one STD after the baseline interview. For both genders, self-reported STD infection before baseline interview was the best predictor of self-reported STD infection 1 year after baseline interview. Female adolescents were more likely to report diagnosis with an STD after baseline if they self-identified as a minority race (other than Asian) and perceived that their mother did not disapprove of their having sex. Female adolescents were less likely to report STDs if they perceived that adults care about them. No additional variables predicted STD diagnosis after baseline for male adolescents. We conclude that past history of STD infection is the most important indicator of subsequent STD infection among adolescents. Thus, this study suggests the benefit of specific clinical efforts designed to promote preventive behavior among adolescents newly diagnosed with an STD.

  5. Declining financial capacity in patients with mild Alzheimer disease: a one-year longitudinal study.

    Science.gov (United States)

    Martin, Roy; Griffith, H Randall; Belue, Katherine; Harrell, Lindy; Zamrini, Edward; Anderson, Britt; Bartolucci, Alfred; Marson, Daniel

    2008-03-01

    The objective of this study was to investigate change over time in financial abilities in patients with mild Alzheimer disease (AD). The authors conducted a prospective 1-year longitudinal study at a large southern U.S. metropolitan-area medical school university. Participants included healthy older adults (N=63) and patients with mild AD (N=55). The authors conducted a standardized performance measure of financial capacity. Performance was assessed on 18 financial tasks, nine domains of financial activity, and overall financial capacity. Capacity outcomes classifications (capable, marginally capable, or incapable) for domains and overall performance were made using cut scores referenced to comparison group performance. At baseline, patients with mild AD performed significantly below healthy older adults on 16 of 18 tasks, on all nine domains, and on overall financial capacity. At one-year follow up, comparison group performance was stable on all variables. In contrast, patients with mild AD showed substantial declines in overall financial capacity, on eight of nine domains, and on 12 of 18 tasks. Similarly, the proportion of the mild AD group classified as marginally capable and incapable increased substantially over one year for the two overall scores and for five financial domains. Financial capacity is already substantially impaired in patients with mild AD at baseline and undergoes rapid additional decline over one year. Relative to the comparison group, overall financial capacity performance in the AD group declined 10%, from approximately 80% of the comparison group performance at baseline to 70% at follow up. Financial skills showed differential rates of decline on both simple and complex tasks. Of clinical and public policy interest was the declining judgment of patients with mild AD regarding simple fraud schemes. The study supports the importance of prompt financial supervision and planning for patients newly diagnosed with AD.

  6. Impact of Perinatally Acquired HIV Disease Upon Longitudinal Changes in Memory and Executive Functioning.

    Science.gov (United States)

    Malee, Kathleen M; Chernoff, Miriam C; Sirois, Patricia A; Williams, Paige L; Garvie, Patricia A; Kammerer, Betsy L; Harris, Lynnette L; Nozyce, Molly L; Yildirim, Cenk; Nichols, Sharon L

    2017-08-01

    Little is known regarding effects of perinatally acquired HIV infection (PHIV) on longitudinal change in memory and executive functioning (EF) during adolescence despite the importance of these skills for independence in adulthood. PHIV (n = 144) and perinatally HIV-exposed uninfected youth (PHEU, n = 79), ages 12-17, completed standardized tests of memory and EF at baseline and 2 years later. Changes from baseline for each memory and EF outcome were compared between PHEU and PHIV youth with (PHIV/C, n = 39) and without (PHIV/non-C, n = 105) history of CDC class C (AIDS-defining) diagnoses. Among PHIV youth, associations of baseline and past disease severity with memory and EF performance at follow-up were evaluated using adjusted linear regression models. Participants were primarily black (79%); 16% were Hispanic; 55% were female. Mean memory and EF scores at follow-up generally fell in the low-average to average range. Pairwise comparison of adjusted mean change from baseline to follow-up revealed significantly greater change for PHIV/non-C compared with PHEU youth in only one verbal recognition task, with a difference in mean changes for PHIV/non-C versus PHEU of -0.99 (95% CI: -1.80 to -0.19; P = 0.02). Among youth with PHIV, better immunologic status at baseline was positively associated with follow-up measures of verbal recall and recognition and cognitive inhibition/flexibility. Past AIDS-defining diagnoses and higher peak viral load were associated with lower performance across multiple EF tasks at follow-up. Youth with PHIV demonstrated stable memory and EF during a 2-year period of adolescence, allowing cautious optimism regarding long-term outcomes.

  7. Longitudinal study of spatially heterogeneous emphysema progression in current smokers with chronic obstructive pulmonary disease.

    Directory of Open Access Journals (Sweden)

    Naoya Tanabe

    Full Text Available BACKGROUND: Cigarette smoke is the main risk factor for emphysema, which is a key pathology in chronic obstructive pulmonary disease (COPD. Low attenuation areas (LAA in computed tomography (CT images reflect emphysema, and the cumulative size distribution of LAA clusters follows a power law characterized by the exponent D. This property of LAA clusters can be explained by model simulation, where mechanical force breaks alveolar walls causing local heterogeneous lung tissue destruction. However, a longitudinal CT study has not investigated whether continuous smoking causes the spatially heterogeneous progression of emphysema. METHODS: We measured annual changes in ratios of LAA (LAA%, D and numbers of LAA clusters (LAN in CT images acquired at intervals of ≥ 3 years from 22 current and 31 former smokers with COPD to assess emphysema progression. We constructed model simulations using CT images to morphologically interpret changes in current smokers. RESULTS: D was decreased in current and former smokers, whereas LAA% and LAN were increased only in current smokers. The annual changes in LAA%, D, and LAN were greater in current, than in former smokers (1.03 vs. 0.37%, p=0.008; -0.045 vs. -0.01, p=0.004; 13.9 vs. 1.1, p=0.007, respectively. When LAA% increased in model simulations, the coalescence of neighboring LAA clusters decreased D, but the combination of changes in D and LAN in current smokers could not be explained by the homogeneous emphysema progression model despite cluster coalescence. Conversely, a model in which LAAs heterogeneously increased and LAA clusters merged somewhat in relatively advanced emphysematous regions could reflect actual changes. CONCLUSIONS: Susceptibility to parenchymal destruction induced by continuous smoking is not uniform over the lung, but might be higher in local regions of relatively advanced emphysema. These could result in the spatially heterogeneous progression of emphysema in current smokers.

  8. Cluster analysis of behavioural weight management strategies and associations with weight change in young women: a longitudinal analysis.

    Science.gov (United States)

    Madigan, C D; Daley, A J; Kabir, E; Aveyard, P; Brown, W

    2015-11-01

    Maintaining a healthy weight is important for the prevention of many chronic diseases. Little is known about the strategies used by young women to manage their weight, or the effectiveness of these in preventing weight gain. We aimed to identify clusters of weight control strategies used by women and to determine the average annual weight change among women in each cluster from 2000 to 2009. Latent cluster analysis of weight control strategies reported by 8125 participants in the Australian Longitudinal Study of Women's Health. Analyses were performed in March-November 2014. Weight control strategies were used by 79% of the women, and four unique clusters were found. The largest cluster group (39.7%) was named dieters as 90% had been on a diet in the past year, and half of these women had lost 5 kg on purpose. Women cut down on size of meals, fats and sugars and took part in vigorous physical activity. Additionally 20% had used a commercial programme. The next largest cluster (30.2%) was the healthy living group who followed the public health messages of 'eat less and move more'. The do nothing group (20%) did not actively control their weight whereas the perpetual dieters group (10.7%) used all strategies, including unhealthy behaviours. On average women gained 700 g per year (over 9 years); however, the perpetual dieters group gained significantly more weight (210 g) than the do nothing group (Phealth guidelines on health eating and physical activity.

  9. Authenticity, life satisfaction, and distress: a longitudinal analysis.

    Science.gov (United States)

    Boyraz, Güler; Waits, J Brandon; Felix, Victoria A

    2014-07-01

    The purpose of the present study was to examine the reciprocal relationships between authenticity and measures of life satisfaction and distress using a 2-wave panel study design. Data were collected from 232 college students attending 2 public universities. Structural equation modeling was used to analyze the data. The results of the cross-lagged panel analysis indicated that after controlling for temporal stability, initial authenticity (Time 1) predicted later distress and life satisfaction (Time 2). Specifically, higher levels of authenticity at Time 1 were associated with increased life satisfaction and decreased distress at Time 2. Neither distress nor life satisfaction at Time 1 significantly predicted authenticity at Time 2. However, the relationship between Time 1 distress and Time 2 authenticity was not significantly different from the relationship between Time 1 authenticity and Time 2 distress. Results are discussed in light of humanistic-existential theories and the empirical research on well-being. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  10. A Longitudinal analysis of the Porterian paradigm utilization in Brazil

    Directory of Open Access Journals (Sweden)

    Simone Sehnem

    2010-01-01

    Full Text Available The purpose of this article is to investigate to what extent Michael Porter's ideas keep attracting the interest of Brazilian researchers vis-à-vis other possibilities. In this research, we conceptualize Porter's paradigm by the the following elements: strategic groups, generic strategies, model of the five forces and value chain. Weanalyzed conferece communications to EnANPAD¿s, from 1998 to 2008, and to 3Es, from 2003to 2007. The results indicate a decline in the use of the porterian paradigm as the main axis of research in strategy. The generic strategies and the model of five forces are the elements of Porter's paradigm most employed, while the concepts of strategic groups and value chain are the ones that received less attention by researchers. The analysis of methodology and purpose of comunications indicates that the "porterian life" in Brazil was characterized by the acritical use of its concepts in order to describe the reality of the strategy in Brazil. There are no evidences of consistent and systematic attempts to test or adapt the porterian paradigm for the Brazilian context. And results indicate no evidences that this trend will be reversed.

  11. Transitions of Adoptive Parents: A Longitudinal Mixed Methods Analysis.

    Science.gov (United States)

    Foli, Karen J; Hebdon, Megan; Lim, Eunjung; South, Susan C

    2017-10-01

    As adoptive parents create a new family, they face myriad changes both pre-and post-placement of their child. The aim of this study was to describe parent perceptions and depressive symptoms during this transition via reports collected with an online survey. Using content analysis, we analyzed a total of 110 responses from 64 parents at three time points: 4-6weeks pre-placement, and 4-6weeks and 5-6months post-placement. Five main themes were revealed: Transition from uncertainty to a new normal; unique experiences related to adoption; rest/fatigue: out of balance; life stressors; and faith/spirituality. Two subthemes were also identified: previous losses (pre-placement) and joy and love (post-placement). During the transition from pre-to post-placement, adoptive parents experience a unique passage, with both challenges and strengths exclusive to this group of parents. While acknowledging the commonalities of some parenting experiences, healthcare and adoption professionals should recognize the unique dynamics that adoption brings to families. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. The Association of Baseline and Longitudinal Change in Endothelial Microparticle Count with Mortality in Chronic Kidney Disease.

    Science.gov (United States)

    Green, Darren; Skeoch, Sarah; Alexander, M Yvonne; Kalra, Philip A; Parker, Ben

    2017-01-01

    Chronic kidney disease (CKD) is associated with a unique milieu of vascular pathology, and effective biomarkers of active vascular damage are lacking. A candidate biomarker is the quantification of circulating endothelial microparticles (EMPs). This study observed baseline and longitudinal EMP change (δEMP) and established the association of these with all-cause mortality and cardiovascular events in CKD. An observational study in adults with CKD (estimated glomerular filtration rate [eGFR] change was not. This may reflect disease-specific EMP behaviour and the limitation of EMP as a generalised biomarker in CKD. © 2017 S. Karger AG, Basel.

  13. Multi-modal neuroimaging in premanifest and early Huntington's disease: 18 month longitudinal data from the IMAGE-HD study.

    Directory of Open Access Journals (Sweden)

    Juan F Domínguez D

    Full Text Available IMAGE-HD is an Australian based multi-modal longitudinal magnetic resonance imaging (MRI study in premanifest and early symptomatic Huntington's disease (pre-HD and symp-HD, respectively. In this investigation we sought to determine the sensitivity of imaging methods to detect macrostructural (volume and microstructural (diffusivity longitudinal change in HD. We used a 3T MRI scanner to acquire T1 and diffusion weighted images at baseline and 18 months in 31 pre-HD, 31 symp-HD and 29 controls. Volume was measured across the whole brain, and volume and diffusion measures were ascertained for caudate and putamen. We observed a range of significant volumetric and, for the first time, diffusion changes over 18 months in both pre-HD and symp-HD, relative to controls, detectable at the brain-wide level (volume change in grey and white matter and in caudate and putamen (volume and diffusivity change. Importantly, longitudinal volume change in the caudate was the only measure that discriminated between groups across all stages of disease: far from diagnosis (>15 years, close to diagnosis (<15 years and after diagnosis. Of the two diffusion metrics (mean diffusivity, MD; fractional anisotropy, FA, only longitudinal FA change was sensitive to group differences, but only after diagnosis. These findings further confirm caudate atrophy as one of the most sensitive and early biomarkers of neurodegeneration in HD. They also highlight that different tissue properties have varying schedules in their ability to discriminate between groups along disease progression and may therefore inform biomarker selection for future therapeutic interventions.

  14. Model selection for marginal regression analysis of longitudinal data with missing observations and covariate measurement error.

    Science.gov (United States)

    Shen, Chung-Wei; Chen, Yi-Hau

    2015-10-01

    Missing observations and covariate measurement error commonly arise in longitudinal data. However, existing methods for model selection in marginal regression analysis of longitudinal data fail to address the potential bias resulting from these issues. To tackle this problem, we propose a new model selection criterion, the Generalized Longitudinal Information Criterion, which is based on an approximately unbiased estimator for the expected quadratic error of a considered marginal model accounting for both data missingness and covariate measurement error. The simulation results reveal that the proposed method performs quite well in the presence of missing data and covariate measurement error. On the contrary, the naive procedures without taking care of such complexity in data may perform quite poorly. The proposed method is applied to data from the Taiwan Longitudinal Study on Aging to assess the relationship of depression with health and social status in the elderly, accommodating measurement error in the covariate as well as missing observations. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Analysis of Longitudinal Waves in Rod-Type Piezoelectric Phononic Crystals

    Directory of Open Access Journals (Sweden)

    Longfei Li

    2016-04-01

    Full Text Available Phononic crystals can be used to control elastic waves due to their frequency bands. This paper analyzes the passive and active control as well as the dispersion properties of longitudinal waves in rod-type piezoelectric phononic crystals over large frequency ranges. Based on the Love rod theory for modeling the longitudinal wave motions in the constituent rods and the method of reverberation-ray matrix (MRRM for deriving the member transfer matrices of the constituent rods, a modified transfer matrix method (MTMM is proposed for the analysis of dispersion curves by combining with the Floquet–Bloch principle and for the calculation of transmission spectra. Numerical examples are provided to validate the proposed MTMM for analyzing the band structures in both low and high frequency ranges. The passive control of longitudinal-wave band structures is studied by discussing the influences of the electrode’s thickness, the Poisson’s effect and the elastic rod inserts in the unit cell. The influences of electrical boundaries (including electric-open, applied electric capacity, electric-short and applied feedback control conditions on the band structures are investigated to illustrate the active control scheme. From the calculated comprehensive frequency spectra over a large frequency range, the dispersion properties of the characteristic longitudinal waves in rod-type piezoelectric phononic crystals are summarized.

  16. Management of outpatients in France with stable coronary artery disease. Findings from the prospeCtive observational LongitudinAl RegIstry oF patients with stable coronary arterY disease (CLARIFY) registry.

    Science.gov (United States)

    Danchin, Nicolas; Ferrieres, Jean; Guenoun, Maxime; Cattan, Simon; Rushton-Smith, Sophie K; Greenlaw, Nicola; Ferrari, Roberto; Steg, Philippe Gabriel

    2014-01-01

    Improvements in the treatment of coronary artery disease mean that an increasing number of patients survive acute cardiovascular events and live as outpatients with or without anginal symptoms. To determine the characteristics and management of contemporary outpatients with stable coronary artery disease in Western Europe, and to compare France with the other Western European countries. CLARIFY (prospeCtive observational LongitudinAl RegIstry oF patients with stable coronary arterY disease) is an international, prospective, observational, longitudinal study. Between November 2009 and July 2010, 32,954 adult outpatients with stable coronary artery disease (defined as a history of documented myocardial infarction [of >3 months], prior coronary revascularization, chest pain with myocardial ischaemia, or coronary stenosis of>50% proven by angiography) were enrolled in 45 countries. The demographics and management of CLARIFY patients enrolled in France were compared with those enrolled in other Western European countries (Austria, Belgium, Denmark, Germany, Greece, Ireland, Italy, Netherlands, Portugal, Spain, Switzerland and the UK). Of the 14,726 patients enrolled in Western Europe (mean age 66.2 [10.2] years; 79.6% male), 2432 (16.5%) were from France. The use of aspirin was lower in France than in other Western European countries (74.5% vs. 86.9%, respectively), whereas use of thienopyridines (48.5% vs. 21.7%), oral anticoagulants (12.3% vs. 9.0%) and lipid-lowering drugs (95.8% vs. 92.5%) was higher. Beta-blockers were used in 73% of both groups. Angina was less prevalent in France (6.3% vs. 15.5%) and French patients showed higher levels of physical activity than their counterparts in Western Europe. The management of patients with stable CAD in France appears favourable, with good adherence to guideline-based therapies, but there remains room for improvement in terms of symptom and risk factor control. Copyright © 2014. Published by Elsevier Masson SAS.

  17. Development of Inflammatory Bowel Disease Is Linked to a Longitudinal Restructuring of the Gut Metagenome in Mice

    Science.gov (United States)

    Sharpton, Thomas; Lyalina, Svetlana; Luong, Julie; Pham, Joey; Deal, Emily M.; Armour, Courtney; Gaulke, Christopher; Sanjabi, Shomyseh

    2017-01-01

    ABSTRACT The gut microbiome is linked to inflammatory bowel disease (IBD) severity and altered in late-stage disease. However, it is unclear how gut microbial communities change over the course of IBD development, especially in regard to function. To investigate microbiome-mediated disease mechanisms and discover early biomarkers of IBD, we conducted a longitudinal metagenomic investigation in an established mouse model of IBD, where damped transforming growth factor β (TGF-β) signaling in T cells leads to peripheral immune activation, weight loss, and severe colitis. IBD development is associated with abnormal gut microbiome temporal dynamics, including damped acquisition of functional diversity and significant differences in abundance trajectories for KEGG modules such as glycosaminoglycan degradation, cellular chemotaxis, and type III and IV secretion systems. Most differences between sick and control mice emerge when mice begin to lose weight and heightened T cell activation is detected in peripheral blood. However, levels of lipooligosaccharide transporter abundance diverge prior to immune activation, indicating that it could be a predisease indicator or microbiome-mediated disease mechanism. Taxonomic structure of the gut microbiome also significantly changes in association with IBD development, and the abundances of particular taxa, including several species of Bacteroides, correlate with immune activation. These discoveries were enabled by our use of generalized linear mixed-effects models to test for differences in longitudinal profiles between healthy and diseased mice while accounting for the distributions of taxon and gene counts in metagenomic data. These findings demonstrate that longitudinal metagenomics is useful for discovering the potential mechanisms through which the gut microbiome becomes altered in IBD. IMPORTANCE IBD patients harbor distinct microbial communities with functional capabilities different from those seen with healthy people

  18. Development of Inflammatory Bowel Disease Is Linked to a Longitudinal Restructuring of the Gut Metagenome in Mice.

    Science.gov (United States)

    Sharpton, Thomas; Lyalina, Svetlana; Luong, Julie; Pham, Joey; Deal, Emily M; Armour, Courtney; Gaulke, Christopher; Sanjabi, Shomyseh; Pollard, Katherine S

    2017-01-01

    The gut microbiome is linked to inflammatory bowel disease (IBD) severity and altered in late-stage disease. However, it is unclear how gut microbial communities change over the course of IBD development, especially in regard to function. To investigate microbiome-mediated disease mechanisms and discover early biomarkers of IBD, we conducted a longitudinal metagenomic investigation in an established mouse model of IBD, where damped transforming growth factor β (TGF-β) signaling in T cells leads to peripheral immune activation, weight loss, and severe colitis. IBD development is associated with abnormal gut microbiome temporal dynamics, including damped acquisition of functional diversity and significant differences in abundance trajectories for KEGG modules such as glycosaminoglycan degradation, cellular chemotaxis, and type III and IV secretion systems. Most differences between sick and control mice emerge when mice begin to lose weight and heightened T cell activation is detected in peripheral blood. However, levels of lipooligosaccharide transporter abundance diverge prior to immune activation, indicating that it could be a predisease indicator or microbiome-mediated disease mechanism. Taxonomic structure of the gut microbiome also significantly changes in association with IBD development, and the abundances of particular taxa, including several species of Bacteroides , correlate with immune activation. These discoveries were enabled by our use of generalized linear mixed-effects models to test for differences in longitudinal profiles between healthy and diseased mice while accounting for the distributions of taxon and gene counts in metagenomic data. These findings demonstrate that longitudinal metagenomics is useful for discovering the potential mechanisms through which the gut microbiome becomes altered in IBD. IMPORTANCE IBD patients harbor distinct microbial communities with functional capabilities different from those seen with healthy people. But is

  19. A LONGITUDINAL ANALYSIS OF PARENTING PRACTICES, COUPLE SATISFACTION, AND CHILD BEHAVIOR PROBLEMS

    OpenAIRE

    Linville, Deanna; Chronister, Krista; Dishion, Tom; Todahl, Jeff; Miller, John; Shaw, Daniel; Gardner, Francis; Wilson, Melvin

    2010-01-01

    This longitudinal study examined the relationship between couple relationship satisfaction, parenting practices, parent depression, and child problem behaviors. The study participants (n = 148) were part of a larger experimental study that examined the effectiveness of a brief family-centered intervention, the Family Check-Up model. Regression analysis results indicated that our proposed model accounted for 38% of the variance in child problem behavior at Time 2, with child problem behavior a...

  20. medplot: a web application for dynamic summary and analysis of longitudinal medical data based on R.

    Directory of Open Access Journals (Sweden)

    Črt Ahlin

    Full Text Available In biomedical studies the patients are often evaluated numerous times and a large number of variables are recorded at each time-point. Data entry and manipulation of longitudinal data can be performed using spreadsheet programs, which usually include some data plotting and analysis capabilities and are straightforward to use, but are not designed for the analyses of complex longitudinal data. Specialized statistical software offers more flexibility and capabilities, but first time users with biomedical background often find its use difficult. We developed medplot, an interactive web application that simplifies the exploration and analysis of longitudinal data. The application can be used to summarize, visualize and analyze data by researchers that are not familiar with statistical programs and whose knowledge of statistics is limited. The summary tools produce publication-ready tables and graphs. The analysis tools include features that are seldom available in spreadsheet software, such as correction for multiple testing, repeated measurement analyses and flexible non-linear modeling of the association of the numerical variables with the outcome. medplot is freely available and open source, it has an intuitive graphical user interface (GUI, it is accessible via the Internet and can be used within a web browser, without the need for installing and maintaining programs locally on the user's computer. This paper describes the application and gives detailed examples describing how to use the application on real data from a clinical study including patients with early Lyme borreliosis.

  1. Analysis of baseline, average, and longitudinally measured blood pressure data using linear mixed models.

    Science.gov (United States)

    Hossain, Ahmed; Beyene, Joseph

    2014-01-01

    This article compares baseline, average, and longitudinal data analysis methods for identifying genetic variants in genome-wide association study using the Genetic Analysis Workshop 18 data. We apply methods that include (a) linear mixed models with baseline measures, (b) random intercept linear mixed models with mean measures outcome, and (c) random intercept linear mixed models with longitudinal measurements. In the linear mixed models, covariates are included as fixed effects, whereas relatedness among individuals is incorporated as the variance-covariance structure of the random effect for the individuals. The overall strategy of applying linear mixed models decorrelate the data is based on Aulchenko et al.'s GRAMMAR. By analyzing systolic and diastolic blood pressure, which are used separately as outcomes, we compare the 3 methods in identifying a known genetic variant that is associated with blood pressure from chromosome 3 and simulated phenotype data. We also analyze the real phenotype data to illustrate the methods. We conclude that the linear mixed model with longitudinal measurements of diastolic blood pressure is the most accurate at identifying the known single-nucleotide polymorphism among the methods, but linear mixed models with baseline measures perform best with systolic blood pressure as the outcome.

  2. Longitudinal changes in white matter disease and cognition in the first year of the Alzheimer disease neuroimaging initiative

    NARCIS (Netherlands)

    Carmichael, Owen; Schwarz, Christopher; Drucker, David; Fletcher, Evan; Harvey, Danielle; Beckett, Laurel; Jack, Clifford R.; Weiner, Michael; Decarli, Charles; Abdi, Herve; Abeliovich, Asa; Abellan van Kan, Gabor; Abner, Erin; Acharya, Deepa; Adams, Nicholas; Adler, Daniel; Agrusti, Antonella; Agyemang, Alex; Ahdidan, Jamila; Ahn, Jae Eun; Aisen, Paul; Aksu, Yaman; Al-Akhras, Mousa; Alarcon, Marcelo; Alberca, Roman; Alexander, Gene; Alexander, Daniel; Almeida, Fabio; Anand, Rishi; Anand, Shyam; Andrew, Marilee; Anjum, Ayesha; Aoyama, Eiji; Ard, Michael Colin; Arfanakis, Konstantinos; Armor, Tom; Arnold, Steven; Asatryan, Albert; Ashe-McNalley, Cody; Ashiga, Hirokazu; Assareh, Arezoo; Aubry, Florent; Avants, Brian; Avinash, Gopal; Awasthi, Sukrati; Ayan-Oshodi, Mosun; Bagci, Ulas; Bai, Shuyang; Baker, John; Banks, Sarah; Bard, Jonathan; Barnes, Josephine; Barret, Olivier; Bartzokis, George; Barua, Neil; Bauer, Corinna; Becker, James; Bednar, Martin; Beg, Mirza Faisal; Bek, Stephan; Bernard, Charlotte; Bertram, Lars; Bhagwagar, Zubin; Biffi, Alessandro; Bilgic, Basar; Bishnoi, Mahesh; Bishop, Courtney; Bittner, Daniel; Black, Ronald; Blennow, Kaj; Bogorodzki, Piotr; Bokde, Arun; Bonner-Jackson, Aaron; Boppana, Madhu; Bourgeat, Pierrick; Bowes, Mike; Bowman, Gene; Bowman, DuBois; Braskie, Meredith; Brewer, James; Brickman, Adam; Broadbent, Steve; Brooks, David; Browndyke, Jeffrey; Bruat, Vanessa; Brunton, Simon; Buchert, Ralph; Buchsbaum, Monte; Buckley, Chris; Burger, Cyrill; Burns, Jeffrey; Burton, David; Butman, John; Cabeza, Rafael; Cairns, Nigel; Callhoff, Johanna; Calvini, Piero; Campbell, Aaron; Cantillon, Marc; Capella, Heraldo; Cardona-Sanclemente, Luis Eduardo; Carle, Adam; Carmasin, Jeremy; Carranza-Ath, Fredy; Casanova, Ramon; Cash, David; Cella, Massimo; Celsis, Pierre; Chan, Lung Tat Andrew; Chaney, Megan; Chanu, Pascal; Chao, Linda; Charil, Arnaud; Chemali, Zeina; Chen, Baojiang; Chen, Kewei; Chen, Ting; Chen, Minhua; Chen, Gennan; Chen, Rong; Cheng, Wei-Chen; Chertkow, Howard; Chiang, Gloria; Chiba, Koji; Chisholm, Jane; Cho, Youngsang; Choe, John; Choubey, Suresh; Christensen, Anette Luther; Clark, Chris; Clark, David; Clarkson, Matt; Clayton, David; Clunie, David; Coimbra, Alexandre; Compton, David; Crane, Paul; Crans, Gerald; Croop, Robert; Crowther, Daniel; Crum, William; Cui, Yue; Curry, Charles; Curtis, Steven; Cutter, Gary; Daiello, Lori; Dake, Michael; Dale, Anders; Damato, Vito Domenico; Darby, Eveleen; Darkner, Sune; Davatzikos, Christos; Dave, Jay; David, Renaud; Davidson, Julie; de Bruijne, Marleen; de Meyer, Geert; de Nunzio, Giorgio; de Santi, Susan; Dechairo, Bryan; DeDuck, Kristina; Dejkam, Arsalan; Delfino, Manuel; Delpassand, Ebrahim; Deniz, Oscar; Denney, Douglas; DeOrchis, Vincent; Depy Carron, Delphine; deToledo-Morrell, Leyla; Devanand, Davangere; Devanarayan, Viswanath; Diaz, Gloria; Diaz-Arrastia, Ramon; Dickerson, Bradford; Dinov, Ivo; Dodge, Hiroko; Donohue, Michael; Dowling, Maritza; Drzezga, Alex; Duan, Xujun; Duchesne, Simon; Duff, Kevin; Dukart, Jurgen; Durazzo, Timothy; Dykstra, Kevin; Earl, Nancy; Edula, Goutham; Ekin, Ahmet; Engelman, Corinne; Epstein, Noam; Erten-Lyons, Deniz; Eskildsen, Simon; Falcone, Guido; Fan, Yong; Farnum, Michael; Farrer, Lindsay; Farzan, Ali; Feldman, Howard; Feng, Yan; Fennema-Notestine, Christine; Fernandes, Michel; Fernandez, Elsa; Ferrarini, Luca; Ferreira, Luiz; Ferrer, Eugene; Figurski, Michal; Filipovych, Roman; Finch, Stephen; Finlay, Daniel; Fiot, Jean-Baptiste; Flenniken, Derek; Fletcher, P. Thomas; Flynn Longmire, Crystal; Forman, Mark; Forsythe, Alan; Fox-Bosetti, Sabrina; Francis, Alexander L.; Franco-Villalobos, Conrado; Franko, Edit; Freeman, Stefanie; Friedrich, Christoph M.; Friesenhahn, Michel; Frings, Lars; Frisoni, Giovanni; Fritzsche, Klaus; Fujimoto, Yoko; Fujiwara, Ken; Fullerton, Terence; Furney, Simon; Gallins, Paul; Gamst, Anthony; Gan, Ke; Garcia, Maria Teresa; Garcia-Linares, Antonio; Garg, Gaurav; Gaser, Christian; Gastineau, Edward; Gavidia, Giovana; Gazdzinski, Stefan; Ge, Qi; Gemme, Gianluca; German, Dwight; Ghassabi, Zeinab; Gil, Juan E.; Gill, Ryan; Gitelman, Darren; Gleason, Carey; Godbey, Michael; Goghari, Vina; Gold, Michael; Goldberg, Terry; Gomeni, Roberto; Gong, Shangwenyan; Gonzales, Celedon; Gordon, Brian; Gorriz, Juan Manuel; Grachev, Igor; Grandey, Emily; Grasela, Thaddeus; Gratt, Jeremy; Gray, Katherine; Greenberg, Barry; Gregg, Keith; Gregory, Erik; Greicius, Michael; Greve, Douglas; Grill, Joshua; Gross, Alan; Guo, Lianghao; Guo, Hongbin; Guo, Jeffrey; Habeck, Christian; Hai, Yizhen; Haight, Thaddeus; Hakansson, Kristina; Hammarstrom, Per; Hampel, Harald; Han, Tony; Han, Jian; Hanif, Muhammad; Hanna, Yousef; Hardy, Peter; Hasan, Md Kamrul; Hazart, Aurelien; Hazel, James; He, Yong; He, Huiguang; Head, Denise; Heckemann, Rolf; Heidebrink, Judith; Henderson, David; Henrard, Sebastien; Herholz, Karl; Hernandez, Monica; Hess, Christopher; Hobart, Jeremy; Hoffman, John; Holder, Daniel; Honigberg, Lee; Horsfield, Mark; Hsu, Wei-Wen; Hsu, Ailing; Hu, Zhenghui; Hu, Zhiwei; Hu, Xiaolan; Hu, William; Huang, Shu-Pang; Huang, Chun-Jung; Huang, Fude; Huang, Yifan; Huang, Juebin; Huang, Chingwen; Hubbard, Rebecca; Huentelman, Matthew; Hui, Shen; Huppertz, Hans-Jurgen; Hurko, Orest; Hurt, Stephen; Huyck, Susan; Hwang, Scott; Hyun, JungMoon; Ifeachor, Emmanuel; Iglesias, Martina; Ikari, Yasuhiko; Immermann, Fred; Inoue, Lurdes; Insel, Philip; Irizarry, Michael; Irungu, Benson mwangi; Ishibashi, Taro; Ishii, Kenji; Ismail, Shahina; Ito, Kaori; Ito, Momoyo; Iwatsubo, Takeshi; Iyer, Madhumitha; Jacobson, Mark; Jacobson, Alex; Jafari, Aria; Jafari-Khouzani, Kourosh; Jaffe, Carl; Jagust, William; Jara, Hernan; Jaros, Mark; Jefferson, Angela; Jiang, Tianzi; Johnson, David K.; Juengling, Freimut; Juh, Rahyeong; Julin, Per; Bhaskar, Uday; Kadish, Bill; Kahle-Wrobleski, Kristin; Kallam, Hanimi Reddy; Kalpathy-Cramer, Jayashree; Karageorgiou, Elissaios; Karantzoulis, Stella; Karasev, Peter; Kauwe, John; Kawakami, Hirofumi; Kazimipoor, Borhan; Kelleher, Thomas; Kennedy, Richard; Kerr, Douglas; Kerrouche, Nacer; Khalil, Iya; Khalil, Andre; Khatry, Deepak; Kihel, Badra; Killeen, Neil; Killiany, Ron; Kim, Hyewon; Kim, Heeyoung; Kim, Yeonhee; Kim, Jong Hun; Kimberg, Daniel; Kimura, Tokunori; King, Richard; Kirby, Justin; Kita, Hiroshi; Klimas, Michael; Klopfenstein, Erin; Kobayashi, Dione; Koikkalainen, Juha; Kokomoor, Anders; Kolasny, Anthony; Kondo, Yusuke; Koppel, Jeremy; Korolev, Igor; Kotran, Nickolas; Kouassi, Alex; Koutsouleris, Nikolaos; Kozma, Lynn; Kramer, Joel; Kratzer, Martina; Kuceyeski, Amy; Kuhn, Felix Pierre; Kulkarni, Mauktik; Kumar, Sreedhar; Kuo, Hsun Ting; Kuo, Julie; Kurosawa, Ken; Kwon, Oh Hun; Laforet, Genevieve; Lai, Song; Lakatos, Anita; Landau, Susan; Landen, Jaren; Lane, Richard; Langbaum, Jessica; Lanius, Vivian; Lavault, Romain; Laxamana, Joel; Le, Trung; Leahy, Richard; Lee, Noah; Lee, Vita; Lee, Joseph H.; Lee, Jong-Min; Lee, Dongsoo; Lee, Junyoung; Lefkimmiatis, Stamatis; Lemaitre, Herve; Lenz, Robert; Lester, Gayle; Levey, Allan; Li, Rui; Li, Wenjun; Li, Shanshan; Li, Lexin; Li, Shi-jiang; Li, Gang; Li, Lin; Li, Yi; Li, Jinhe; Li, Chin-Shang; Liang, Peipeng; Liang, Lichen; Liao, Yuan-Lin; Lin, Mingkuan; Lin, Lan; Lin, Ling-chih; Liu, Tao; Liu, Meijie; Liu, Yuan; Liu, Dazhong; Liu, Pu; Liu, Songling; Liu, Xiuwen; Liu, Tianming; Lo, Raymond; Logovinsky, Veronika; Lois, Augusto; Long, Xiaojing; Long, Ziyi; Looi, Jeffrey; Lu, Yuan; Lu, Po-Haong; Lukic, Ana; Lull, Juan J.; Lynch, John; Ma, Lei; Mackin, Scott; Magda, Sebastian; Maglio, Silvio; Mak, Henry Ka-Fung; Malave, Vicente; Mandal, Pravat; Mangin, Jean-Francois; Manohar, Deepak; Mansouri, Chemseddine; Mantri, Ninad; Manzour, Amir; Marambaud, Philippe; Marchewka, Artur; Marek, Kenneth; Markind, Samuel; Marshall, Gad; Martin, Jacob; Mather, Mara; Mathis, Chester; Matoug, Sofia; Matsuo, Yoshiyuki; Matthews, Dawn; Mayo, Agustin; McEvoy, Linda; McGeown, William; McIntyre, John; McQuail, Joseph; Meadowcroft, Mark; Meda, Shashwath; Mehta, Nirav; Mele, Valeria; Mendonca, Brian; Menendez, Manuel; Meredith, Jere; Merrill, David; Mesulam, Marek-Marsel; Meyer, Carsten; Mez, Jesse; Mickael, Guedj; Miftahof, Roustem; Mikhno, Arthur; Miller, David; Min, Ye; Miri, Roham; Mirza, Mubeena; Mitsis, Effie; Mohan, Ananth; Monno, Laura; Montana, Giovanni; Moore, Dana; Birgani, Parmida Moradi; Moratal, David; Morimoto, Bruce; Mortamet, Benedicte; Motyl, Rafal; Mueller, Notger; Mukherjee, Shubhabrata; Mulder, Emma; Murphy, Michael; Murray, Brian; Musiek, Erik; Myers, Amanda; Najafi, Shahla; Nazeri, Arash; Nettiksimmons, Jasmine; Neu, Scott; Neves, Simone; Ng, Yen-Bee; Nguyen, Danh; Nguyen, Nghi; Nguyen Xuan, Tuong; Nielsen, Casper; Nuneez Benjumea, Francisco; O'Neil, Alison; Obisesan, Thomas; Oh, Dong Hoon; Oh, Joonmi; Okonkwo, Ozioma; Olde Rikkert, Marcel; Ollesch, Julian; Olmos, Salvador; Ostrowitzki, Susanne; Oswald, Annahita; Ott, Brian; Ourselin, Sebastien; Ouyang, Gaoxiang; Paiva, Renata; Pan, Zhifang; Pande, Yogesh; Pardoe, Heath; Park, Kee Hyung; Park, Hyunjin; Parsey, Ramin; Parveen, Riswana; Paskavitz, James; Patel, Yogen; Patil, Manasi; Paul, Robert; Pawlak, Mikolaj; Peavy, Guerry; Peng, Yahong; Pepin, Jean louis; Perea, Rodrigo; Perneczky, Robert; Petitti, Diana; Petrella, Jeffrey; Peyrat, Jean-Marc; Pezoa, Jorge; Pham, Chi-Tuan; Phillips, Nicole; Piovezan, Mauro; Podhorski, Adam; Pollari, Mika; Pontecorvo, Michael; Poppenk, Jordan; Posner, Holly; Potkin, Steven; Poulin, Stephane; Prasad, Gautam; Prenger, Kurt; Prieto, Elena; Prince, Jerry; Puchakayala, Shashidhar Reddy; Qin, Wei; Qiu, Ruolun; Qiu, Wendy; Qiu, Anqi; Qualls, Constance Dean; Rabie, Huwaida; Rajeesh, Rajeesh; Rajeesh, J. Rajeesh; Rallabandi, V. P. Subramanyam; Ramage, Amy; Randolph, Christopher; Raniga, Parnesh; Rao, Divya; Rao, Anil; Raubertas, Richard; Ray, Debashis; Razak, Hana; Redolfi, Alberto; Reid, Andrew; Reilhac, Anthonin; Reinsberger, Claus; Restrepo, Lucas; Retico, Alessandra; Rezaeitabar, Yousef; Richards, John; Richter, Mirco; Riddle, William; Ries, Michele; Rincon, Mariano; Rischall, Matt; Robieson, Weining; Rocha-Rego, Vanessa; Rogalski, Emily; Rogers, Elizabeth; Rojas, Ignacio; Romero, Klaus; Rosand, Jonathan; Rosen, Ori; Rosen, Allyson; Rosenberg, Paul; Ross, David; Ross, Joel; Rousseau, Francois; Rowe, Christopher; Rubin, Daniel; Ruiz, Agustin; Rusinek, Henry; Ryan, Laurie; Saad, Ahmed; Sabbagh, Marway; Sabuncu, Mert; Sachs, Michael; Sacuiu, Simona; Sadeghi, Ali; Said, Yasmine; Saint-Aubert, Laure; Sakata, Muneyuki; Salat, David; Salmon, David; Salomi, Sharmila; Salter, Hugh; Samwald, Matthias; Sanchez, Luciano; Sanjo, Nobuo; Sankaranarayanan, Preethi; Sato, Shinji; Sato, Hajime; Saumier, Daniel; Savio, Alexandre; Sawada, Ikuhisa; Saykin, Andrew; Schaffer, J. David; Scharre, Douglas; Schlosser, Gretchen; Schmand, Ben; Schmansky, Nick; Schmidt, Mark; Schneider, Lon; Schramm, Hauke; Schuerch, Markus; Schwartz, Eben; Schwartz, Craig; Schwarz, Adam; Seethamraju, Ravi; Seixas, Flavio; Selnes, Per; Senjem, Matthew; Senlin, Wang; Seo, Sang Won; Sethuraman, Gopalan; Sevigny, Jeffrey; Sfikas, Giorgos; Shahbaba, Babak; Shams, Soheil; Shankle, William; Shattuck, David; Shaw, Leslie; Sheela, Jaba; Shen, Weijia; Shera, David; Sherman, John; Sherman, Michelle; Sherva, Richard; Shimizu, Keiji; Shuler, Catherine; Shulman, Joshua; Siegel, Rene; Siemers, Eric; Silveira, Margarida; Silver, Michael; Silverman, Daniel; Simmons, Andy; Simpson, Ivor; Singh, Simer Preet; Singh, Nikhil; Siuciak, Judy; Sjogren, Niclas; Skup, Martha; Small, Gary; Smith, Benjamin; Smith, Michael; Smith, Charles; Smyth, Timothy; Snow, Sarah; Soares, Holly; Soldea, Octavian; Solomon, Paul; Solomon, Alan; Song, Mingli; Song, Changhong; Sorensen, Greg; Soudah, Eduardo; Spampinato, Maria Vittoria; Spenger, Christian; Sperling, Reisa; Spiegel, Rene; Spies, Lothar; Squarcia, Sandro; Squire, Larry; Staff, Roger; Stern, Yaakov; Strittmatter, Stephen; Styren, Scot; Sugishita, Morihiro; Sugishita, Kazuyuki; Sukkar, Rafid; Sun, Jia; Sun, Yu; Sundell, Karen; Suri, Muhammad; Swan, Melanie; Takagi, Toshihisa; Takahasi, Tetsuhiko; Takeuchi, Tomoko; Tang, Songyuan; Tanner, William; Tao, Wenwen; Tao, Dacheng; Tariot, Pierre; Tarjoman, Mana; Tatsuoka, Curtis; Taylor-Reinwald, Lisa; Terlizzi, Rita; Thiele, Frank; Thomas, Ronald; Thomas, Benjamin; Thompson, Paul; Thompson, Wesley; Thornton-Wells, Tricia; Thurfjell, Lennart; Titeux, Laurence; Tolli, Tuomas; Toma, Ahmed; Tomita, Naoki; Toro, Roberto; Tosun, Duygu; Toussaint, Paule; Toyoshiba, Hiroyoshi; Tractenberg, Rochelle E.; Trittschuh, Emily; Truran, Diana; Tsechpenakis, Gavriil; Tucker-Drob, Elliot; Tung, Joyce; Uesugi, Humito; Ullrich, Lauren; Umadevi Venkataraju, Kannan; Umar, Nisser; Uzunbas, Gokhan; Valdivia, Fernando; van Horn, John; van Leemput, Koen; van Train, Kenneth; van Zeeland, Ashley; Vargas, Gabriel; Vasanawala, Minal; Vemuri, Prashanthi; Verwaerde, Philippe; Videbaek, Charlotte; Vidoni, Eric; Vigneron, Vincent; Villanueva-Meyer, Javier; Visser, Pieter Jelle; Vitolo, Ottavio; Vlassenko, Andrei; Volkau, Ihar; Vounou, Maria; Wade, Sara; Walhovd, Kristine B.; Wallace, Douglas; Wan, Hong; Wang, Angela; Wang, Li-San; Wang, Yongmei Michelle; Wang, Yaping; Wang, Alex; Wang, Lubin; Wang, Yalin; Wang, Tiger; Wang, Yue; Wang, Huanli; Wang, Huali; Ward, Michael; Warfield, Simon; Waring, Stephen; Webb, David; Wei, Lili; Wen, Shu-Hui; Wenjing, Li; Wenzel, Fabian; Westlye, Lars T.; Whitcher, Brandon; Whitwell, Jennifer; WilliamFaltaos, Demiana; Williams, David; Wilmot, Beth; Wingo, Thomas; Winkler, Andreas; Wiste, Heather; Wolfson, Tanya; Wolke, Ira; Wolz, Robin; Woo, Jongwook; Woo, Ellen; Woods, Lynn; Worth, Andrew; Worth, Eric; Wouters, Hans; Wu, Liang; Wu, Xiaoling; Wu, Yi Gen; Wu, Teresa; Wyman, Bradley; Wyss-Coray, Tony; Xiao, Liu; Xu, Guofan; Xu, Jun; Yamane, Tomohiko; Yamashita, Fumio; Yamazawa, Maki; Yan, Yunyi; Yan, Pingkun; Yang, Qing X.; Yang, Zhitong; Ye, Byoung Seok; Ye, Jieping; Yee, Laura; Yesavage, Jerome; Yip, WaiKuan; Yoo, Bongin; Yuan, Kai; Yushkevich, Paul; Zagorodnov, Vitali; Zagorski, Michael; Zawadzki, Rezi; Zeitzer, Jamie; Zhang, Linda; Zhang, Lijun; Zhang, Tianhao; Zhang, Huixiong; Zhang, Bin; Zhang, Kurt; Zhao, Qinying; Zhao, Peng; Zhen, Xiantong; Zheng, Yuanjie; Zhijun, Yao; Zhou, Sheng; Zhou, Bin; Zhou, Luping; Zhu, Wanlin; Zhu, Hongtu; Zou, Heng

    2010-01-01

    To evaluate relationships between magnetic resonance imaging (MRI)-based measures of white matter hyperintensities (WMHs), measured at baseline and longitudinally, and 1-year cognitive decline using a large convenience sample in a clinical trial design with a relatively mild profile of

  3. Automated longitudinal intra-subject analysis (ALISA) for diffusion MRI tractography

    DEFF Research Database (Denmark)

    Aarnink, Saskia H; Vos, Sjoerd B; Leemans, Alexander

    2014-01-01

    the inter-subject and intra-subject automation in this situation are intended for subjects without gross pathology. In this work, we propose such an automated longitudinal intra-subject analysis (dubbed ALISA) approach, and assessed whether ALISA could preserve the same level of reliability as obtained....... The major disadvantage of manual FT segmentations, unfortunately, is that placing regions-of-interest for tract selection can be very labor-intensive and time-consuming. Although there are several methods that can identify specific WM fiber bundles in an automated way, manual FT segmentations across...... multiple subjects performed by a trained rater with neuroanatomical expertise are generally assumed to be more accurate. However, for longitudinal DTI analyses it may still be beneficial to automate the FT segmentation across multiple time points, but then for each individual subject separately. Both...

  4. Two-level mixed modeling of longitudinal pedigree data for genetic association analysis

    DEFF Research Database (Denmark)

    Tan, Q.

    2013-01-01

    of follow-up. Approaches have been proposed to integrate kinship correlation into the mixed effect models to explicitly model the genetic relationship which have been proven as an efficient way for dealing with sample clustering in pedigree data. Although useful for adjusting relatedness in the mixed...... assess the genetic associations with the mean level and the rate of change in a phenotype both with kinship correlation integrated in the mixed effect models. We apply our method to longitudinal pedigree data to estimate the genetic effects on systolic blood pressure measured over time in large pedigrees......Genetic association analysis on complex phenotypes under a longitudinal design involving pedigrees encounters the problem of correlation within pedigrees which could affect statistical assessment of the genetic effects on both the mean level of the phenotype and its rate of change over the time...

  5. [A case of MM1+2 Creutzfeldt-Jakob disease with a longitudinal study of EEG and MRI].

    Science.gov (United States)

    Katsube, Mizuho; Shiota, Yuri; Harada, Takayuki; Shibata, Hiroshi; Nagai, Atsushi

    2013-11-01

    We report a case of definite MM1 + 2 sporadic Creutzfeldt-Jakob disease (sCJD). A 66-year-old woman was admitted to our hospital with memory disturbance and disorientation for three months. On admission she presented a progressive cognitive insufficiency. Electroencephalography (EEG) revealed a frontal intermittent rhythmical delta activity (FIRDA) and the brain magnetic resonance imaging (MRI) showed high signal intensities in cerebral cortex on diffusion weighted images (DWI). After four months from the onset, she reached the akinetic mutism state followed by myoclonus. Follow up examination revealed that periodic synchronous discharge (PSD) was found in EEG, and DWI revealed enlargement of high signal intensity lesions in cerebral cortex. At seven months from the onset, PSD and high signal intensities of cortex became unclear with disappearance of myoclonus, and brain white matter lesions were evident on MRI. Serial studies of EEG and MRI revealed that PSD generalized from frontal lobe dominant pattern, while high signal intensity lesions of cortex diffusely increased on DWI. At ten months from the onset patient died. Pathological examination in brain showed moderate and diffuse neuronal cell loss and gliosis in cerebral cortex corresponding with DWI changes. The genotype at codon 129 of the prion protein (PrP) was homozygous methionine (MM) and the type of protease-resistant PrP (PrPres) was the mixed type of 1 and 2 in Western blot analysis. It has been rare to analyze the changes of EEG and MRI in the entire stage and to investigate pathological finding in the case of sCJD-MM1 + 2. A longitudinal examination of EEG and MRI is useful for early diagnosis of CJD. Also we could correlate these findings with clinical and histopathological phenotype.

  6. Untreated periodontal disease in Indonesian adolescents : Longitudinal clinical data and prospective clinical and microbiological risk assessment

    NARCIS (Netherlands)

    Timmerman, MF; Van der Weijden, GA; Abbas, F; Arief, EM; Armand, S; Winkel, EG; Van Winkelhoff, AJ; Van der Velden, U

    2000-01-01

    Background, aims: In order to investigate the role of various putative clinical and microbiological risk markers, a longitudinal study was initiated in a young population deprived of regular dental care. In 1987 all inhabitants in the age range 15-25 years living in a village with approximately 2000

  7. Personality Predicts Mortality Risk: An Integrative Data Analysis of 15 International Longitudinal Studies.

    Science.gov (United States)

    Graham, Eileen K; Rutsohn, Joshua P; Turiano, Nicholas A; Bendayan, Rebecca; Batterham, Philip J; Gerstorf, Denis; Katz, Mindy J; Reynolds, Chandra A; Sharp, Emily S; Yoneda, Tomiko B; Bastarache, Emily D; Elleman, Lorien G; Zelinski, Elizabeth M; Johansson, Boo; Kuh, Diana; Barnes, Lisa L; Bennett, David A; Deeg, Dorly J H; Lipton, Richard B; Pedersen, Nancy L; Piccinin, Andrea M; Spiro, Avron; Muniz-Terrera, Graciela; Willis, Sherry L; Schaie, K Warner; Roan, Carol; Herd, Pamela; Hofer, Scott M; Mroczek, Daniel K

    2017-10-01

    This study examined the Big Five personality traits as predictors of mortality risk, and smoking as a mediator of that association. Replication was built into the fabric of our design: we used a Coordinated Analysis with 15 international datasets, representing 44,094 participants. We found that high neuroticism and low conscientiousness, extraversion, and agreeableness were consistent predictors of mortality across studies. Smoking had a small mediating effect for neuroticism. Country and baseline age explained variation in effects: studies with older baseline age showed a pattern of protective effects (HReffects for extraversion. This study demonstrated coordinated analysis as a powerful approach to enhance replicability and reproducibility, especially for aging-related longitudinal research.

  8. Preliminary Analysis Using Multi-atlas Labeling Algorithms for Tracing Longitudinal Change

    Directory of Open Access Journals (Sweden)

    Eun Young eKim

    2015-07-01

    Full Text Available Multicenter longitudinal neuroimaging has great potential to provide efficient and consistent biomarkers for research of neurodegenerative diseases and aging. In rare disease studies it is of primary importance to have a reliable tool that performs consistently for data from many different collection sites to increase study power. A multi-atlas labeling algorithm is a powerful brain image segmentation approach that is becoming increasingly popular in image processing. The present study examined the performance of multi-atlas labeling tools for subcortical identification using two types of in-vivo image database: Traveling Human Phantom and PREDICT-HD. We compared the accuracy (Dice Similarity Coefficient; DSC and intraclass correlation; ICC, multicenter reliability (Coefficient of Variance; CV, and longitudinal reliability (volume trajectory smoothness and Akaike Information Criterion; AIC of three automated segmentation approaches: two multi-atlas labeling tools, MABMIS and MALF, and a machine-learning-based tool, BRAINSCut. In general, MALF showed the best performance (higher DSC, ICC, lower CV, AIC, and smoother trajectory with a couple of exceptions. First, the results of accumben, where BRAINSCut showed higher reliability, were still premature to discuss their reliability levels since their validity is still in doubt (DSC<0.7, ICC < 0.7. For caudate, BRAINSCut presented slightly better accuracy while MALF showed significantly smoother longitudinal trajectory. We discuss advantages and limitations of these performance variations and conclude that improved segmentation quality can be achieved using multi-atlas labeling methods. While multi-atlas labeling methods are likely to help improve overall segmentation quality, caution has to be taken when one chooses an approach, as our results suggest that segmentation outcome can vary depending on research interest.

  9. Factors promoting health-related quality of life in people with rheumatic diseases: a 12 month longitudinal study

    Science.gov (United States)

    2011-01-01

    Background Rheumatic diseases have a significant adverse impact on the individual from physical, mental and social aspects, resulting in a low health-related quality of life (HRQL). There is a lack of longitudinal studies on HRQL in people with rheumatic diseases that focus on factors promoting HRQL instead of risk factors. The aim of this study was to investigate the associations between suggested health promoting factors at baseline and outcome in HRQL at a 12 month follow-up in people with rheumatic diseases. Methods A longitudinal cohort study was conducted in 185 individuals with rheumatic diseases with questionnaires one week and 12 months after rehabilitation in a Swedish rheumatology clinic. HRQL was assessed by SF-36 together with suggested health factors. The associations between SF-36 subscales and the health factors were analysed by multivariable logistic regressions. Results Factors predicting better outcome in HRQL in one or several SF-36 subscales were being younger or middle-aged, feeling painless, having good sleep structure, feeling rested after sleep, performing low effort of exercise more than twice per week, having strong sense of coherence (SOC), emotional support and practical assistance, higher educational level and work capacity. The most important factors were having strong SOC, feeling rested after sleep, having work capacity, being younger or middle-aged, and having good sleep structure. Conclusions This study identified several factors that promoted a good outcome in HRQL to people with rheumatic diseases. These health factors could be important to address in clinical work with rheumatic diseases in order to optimise treatment strategies. PMID:21599884

  10. The effects of cognitive reserve and lifestyle on cognition and dementia in Parkinson's disease--a longitudinal cohort study.

    Science.gov (United States)

    Hindle, John V; Hurt, Catherine S; Burn, David J; Brown, Richard G; Samuel, Mike; Wilson, Kenneth C; Clare, Linda

    2016-01-01

    Cognitive reserve theory seeks to explain the observed mismatch between the degree of brain pathology and clinical manifestations. Early-life education, midlife social and occupational activities and later-life cognitive and social interactions are associated with a more favourable cognitive trajectory in older people. Previous studies of Parkinson's disease (PD) have suggested a possible role for the effects of cognitive reserve, but further research into different proxies for cognitive reserve and longitudinal studies is required. This study examined the effects of cognitive lifestyle on cross-sectional and longitudinal measures of cognition and dementia severity in people with PD. Baseline assessments of cognition, and of clinical, social and demographic information, were completed by 525 participants with PD. Cognitive assessments were completed by 323 participants at 4-year follow-up. Cognition was assessed using the measures of global cognition dementia severity. Cross-sectional and longitudinal serial analyses of covariance for cognition and binomial regression for dementia were performed. Higher educational level, socio-economic status and recent social engagement were associated with better cross-sectional global cognition. In those with normal cognition at baseline, higher educational level was associated with better global cognition after 4 years. Increasing age and low levels of a measure of recent social engagement were associated with an increased risk of dementia. Higher cognitive reserve has a beneficial effect on performance on cognitive tests and a limited effect on cognitive decline and dementia risk in PD. Copyright © 2015 John Wiley & Sons, Ltd.

  11. Bayesian Nonparametric Regression Analysis of Data with Random Effects Covariates from Longitudinal Measurements

    KAUST Repository

    Ryu, Duchwan

    2010-09-28

    We consider nonparametric regression analysis in a generalized linear model (GLM) framework for data with covariates that are the subject-specific random effects of longitudinal measurements. The usual assumption that the effects of the longitudinal covariate processes are linear in the GLM may be unrealistic and if this happens it can cast doubt on the inference of observed covariate effects. Allowing the regression functions to be unknown, we propose to apply Bayesian nonparametric methods including cubic smoothing splines or P-splines for the possible nonlinearity and use an additive model in this complex setting. To improve computational efficiency, we propose the use of data-augmentation schemes. The approach allows flexible covariance structures for the random effects and within-subject measurement errors of the longitudinal processes. The posterior model space is explored through a Markov chain Monte Carlo (MCMC) sampler. The proposed methods are illustrated and compared to other approaches, the "naive" approach and the regression calibration, via simulations and by an application that investigates the relationship between obesity in adulthood and childhood growth curves. © 2010, The International Biometric Society.

  12. Cognitive function and advanced kidney disease: longitudinal trends and impact on decision-making.

    Science.gov (United States)

    Iyasere, Osasuyi; Okai, David; Brown, Edwina

    2017-02-01

    Background: Cognitive impairment commonly affects renal patients. But little is known about the influence of dialysis modality on cognitive trends or the influence of cognitive impairment on decision-making in renal patients. This study evaluated cognitive trends amongst chronic kidney disease (CKD), haemodialysis (HD) and peritoneal dialysis (PD) patients. The relationship between cognitive impairment and decision-making capacity (DMC) was also assessed. Methods: Patients were recruited from three outpatient clinics. Cognitive function was assessed 4-monthly for up to 2 years, using the Montreal Cognitive Assessment (MoCA) tool. Cognitive trends were assessed using mixed model analysis. DMC was assessed using the Macarthur Competency Assessment tool (MacCAT-T). MacCAT-T scores were compared between patients with cognitive impairment (MoCA cognitive impairment had lower MacCAT-T compared with those without [median (interquartile range) 19 (17.9-19.6) versus 17.4 (16.3-18.4); P = 0.049]. Conclusions: Cognition declines faster in dialysis patients compared with CKD patients and in HD patients compared with PD patients. Cognitive impairment affects DMC in patients with advanced kidney disease.

  13. Longitudinal anterior-to-posterior shift of collateral channels in patients with moyamoya disease: an implication for its hemorrhagic onset.

    Science.gov (United States)

    Yamamoto, Shusuke; Hori, Satoshi; Kashiwazaki, Daina; Akioka, Naoki; Kuwayama, Naoya; Kuroda, Satoshi

    2018-03-23

    OBJECTIVE This study aimed to assess longitudinal changes in the collateral channels originating from the lenticulostriate artery (LSA), posterior communicating artery (PCoA), and anterior and posterior choroidal arteries (AChA and PChA, respectively) during disease progression and/or aging. The impact of collateral channels on onset type was also examined. METHODS This study included 71 involved hemispheres in 41 patients with moyamoya disease. The disease was categorized into 6 stages according to Suzuki's angiographic staging system. The degree of development of each moyamoya vessel was categorized into 3 grades. RESULTS The LSA started to dilate in stage 2, showed the most prominent development in stage 3, and decreased in more advanced stages (p PCoA started to dilate in stage 3 and showed the most prominent development in stage 4 (p = 0.03). The PChA started to dilate in stage 3 and showed the most prominent development in stages 4 to 5 (p PCoA (p = 0.02, R = 0.28) and PChA (p PCoA, AChA, and PChA more distinctly developed in hemispheres with intracerebral or intraventricular hemorrhage than in hemispheres with ischemic stroke or transient ischemic attack (p < 0.001, p = 0.03, and p = 0.03, respectively). CONCLUSIONS This study suggests that the collateral channels through moyamoya vessels longitudinally shift from the anterior to posterior component during disease progression and aging, which may be closely related to the onset of hemorrhagic stroke in adult moyamoya disease.

  14. Identification of associations between genotypes and longitudinal phenotypes via temporally-constrained group sparse canonical correlation analysis.

    Science.gov (United States)

    Hao, Xiaoke; Li, Chanxiu; Yan, Jingwen; Yao, Xiaohui; Risacher, Shannon L; Saykin, Andrew J; Shen, Li; Zhang, Daoqiang

    2017-07-15

    Neuroimaging genetics identifies the relationships between genetic variants (i.e., the single nucleotide polymorphisms) and brain imaging data to reveal the associations from genotypes to phenotypes. So far, most existing machine-learning approaches are widely used to detect the effective associations between genetic variants and brain imaging data at one time-point. However, those associations are based on static phenotypes and ignore the temporal dynamics of the phenotypical changes. The phenotypes across multiple time-points may exhibit temporal patterns that can be used to facilitate the understanding of the degenerative process. In this article, we propose a novel temporally constrained group sparse canonical correlation analysis (TGSCCA) framework to identify genetic associations with longitudinal phenotypic markers. The proposed TGSCCA method is able to capture the temporal changes in brain from longitudinal phenotypes by incorporating the fused penalty, which requires that the differences between two consecutive canonical weight vectors from adjacent time-points should be small. A new efficient optimization algorithm is designed to solve the objective function. Furthermore, we demonstrate the effectiveness of our algorithm on both synthetic and real data (i.e., the Alzheimer's Disease Neuroimaging Initiative cohort, including progressive mild cognitive impairment, stable MCI and Normal Control participants). In comparison with conventional SCCA, our proposed method can achieve strong associations and discover phenotypic biomarkers across multiple time-points to guide disease-progressive interpretation. The Matlab code is available at https://sourceforge.net/projects/ibrain-cn/files/ . dqzhang@nuaa.edu.cn or shenli@iu.edu. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

  15. Clinical pharmacology quality assurance program: models for longitudinal analysis of antiretroviral proficiency testing for international laboratories.

    Science.gov (United States)

    DiFrancesco, Robin; Rosenkranz, Susan L; Taylor, Charlene R; Pande, Poonam G; Siminski, Suzanne M; Jenny, Richard W; Morse, Gene D

    2013-10-01

    Among National Institutes of Health HIV Research Networks conducting multicenter trials, samples from protocols that span several years are analyzed at multiple clinical pharmacology laboratories (CPLs) for multiple antiretrovirals. Drug assay data are, in turn, entered into study-specific data sets that are used for pharmacokinetic analyses, merged to conduct cross-protocol pharmacokinetic analysis, and integrated with pharmacogenomics research to investigate pharmacokinetic-pharmacogenetic associations. The CPLs participate in a semiannual proficiency testing (PT) program implemented by the Clinical Pharmacology Quality Assurance program. Using results from multiple PT rounds, longitudinal analyses of recovery are reflective of accuracy and precision within/across laboratories. The objectives of this longitudinal analysis of PT across multiple CPLs were to develop and test statistical models that longitudinally: (1) assess the precision and accuracy of concentrations reported by individual CPLs and (2) determine factors associated with round-specific and long-term assay accuracy, precision, and bias using a new regression model. A measure of absolute recovery is explored as a simultaneous measure of accuracy and precision. Overall, the analysis outcomes assured 97% accuracy (±20% of the final target concentration of all (21) drug concentration results reported for clinical trial samples by multiple CPLs). Using the Clinical Laboratory Improvement Act acceptance of meeting criteria for ≥2/3 consecutive rounds, all 10 laboratories that participated in 3 or more rounds per analyte maintained Clinical Laboratory Improvement Act proficiency. Significant associations were present between magnitude of error and CPL (Kruskal-Wallis P Kruskal-Wallis P < 0.001).

  16. Changes in cognitive control in pre-manifest Huntington's disease examined using pre-saccadic EEG potentials - a longitudinal study.

    Science.gov (United States)

    Ness, Vanessa; Bestgen, Anne-Kathrin; Saft, Carsten; Beste, Christian

    2014-01-01

    It is well-known that Huntington's disease (HD) affects saccadic processing. However, saccadic dysfunctions in HD may be seen as a result of dysfunctional processes occurring at the oculomotor level prior to the execution of saccades, i.e., at a pre-saccadic level. Virtually nothing is known about possible changes in pre-saccadic processes in HD. This study examines pre-saccadic processing in pre-manifest HD gene mutation carriers (pre-HDs) by using clinically available EEG measures. Error rates, pre-saccadic EEG potentials and saccade onset EEG potentials were measured in 14 pre-HDs and case-matched controls performing prosaccades and antisaccades in a longitudinal study over a 15-month period. The results show that pre-saccadic potentials were changed in pre-HDs, relative to controls and also revealed changes across the 15-month longitudinal period. In particular, pre-saccadic ERP in pre-HDs were characterized by lower amplitudes and longer latencies, which revealed longitudinal changes. These changes were observed for anti-saccades, but not for pro-saccades. Overt saccadic trajectories (potentials) were not different to those in controls, showing that pre-saccadic processes are sensitive to subtle changes in fronto-striatal networks in pre-HDs. Deficits in pre-saccadic processes prior the execution of an erroneous anti-saccade can be seen as an effect of dysfunctional cognitive control in HD. This may underlie saccadic abnormalities and hence a major phenotype of HD. Pre-saccadic EEG potentials preceding erroneous anti-saccades are sensitive to pre-manifest disease progression in HD.

  17. Baseline prevalence and longitudinal evolution of non-motor symptoms in early Parkinson's disease: the PPMI cohort.

    Science.gov (United States)

    Simuni, Tanya; Caspell-Garcia, Chelsea; Coffey, Christopher S; Weintraub, Daniel; Mollenhauer, Brit; Lasch, Shirley; Tanner, Caroline M; Jennings, Danna; Kieburtz, Karl; Chahine, Lana M; Marek, Kenneth

    2018-01-01

    To examine the baseline prevalence and longitudinal evolution in non-motor symptoms (NMS) in a prospective cohort of, at baseline, patients with de novo Parkinson's disease (PD) compared with healthy controls (HC). Parkinson's Progression Markers Initiative (PPMI) is a longitudinal, ongoing, controlled study of de novo PD participants and HC. NMS were rated using the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part I score and other validated NMS scales at baseline and after 2 years. Biological variables included cerebrospinal fluid (CSF) markers and dopamine transporter imaging. 423 PD subjects and 196 HC were enrolled and followed for 2 years. MDS-UPDRS Part I total mean (SD) scores increased from baseline 5.6 (4.1) to 7.7 (5.0) at year 2 in PD subjects (pbaseline NMS score was associated with female sex (p=0.008), higher baseline MDS-UPDRS Part II scores (pbaseline. There was no association with the dose or class of dopaminergic therapy. This study of NMS in early PD identified clinical and biological variables associated with both baseline burden and predictors of progression. The association of a greater longitudinal increase in NMS with lower baseline Aβ1-42 level is an important finding that will have to be replicated in other cohorts. ClinicalTrials.gov identifier: NCT01141023. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. SELECTIVE MODAL ANALYSIS OF POWER FLOW OSCILLATION IN LARGE SCALE LONGITUDINAL POWER SYSTEMS

    Directory of Open Access Journals (Sweden)

    Wirindi -

    2009-06-01

    Full Text Available Novel selective modal analysis for the determination of low frequency power flow oscillation behaviour based on eigenvalues with corresponding damping ratio, cumulative damping index, and participation factors is proposed. The power system being investigated consists of three large longitudinally interconnected areas with some weak tie lines. Different modes, such as exciter modes, inter area modes, and local modes of the dominant poles are fully studied to find out the significant level of system damping and other factors producing power flow instability. The nature of the energy exchange between area is determined and strategic power flow stability improvement is developed and tested.

  19. Longitudinal Analysis of Somatic Cell Count for Joint Genetic Evaluation of Mastitis and Recovery Liability

    DEFF Research Database (Denmark)

    Welderufael, Berihu Gebremedhin; de Koning, D J; Janss, Luc

    Abstract Text: Better models of genetic evaluation for mastitis can be developed through longitudinal analysis of somatic cell count (SCC) which usually is used as a proxy for mastitis. Mastitis and recovery data with weekly observations of SCC were simulated for daughter groups of 60 and 240 per...... sire. Data were created to define cases: 1 if SCC was above a pre-specified boundary, else 0. A transition from below to above the boundary indicates probability to contract mastitis, and the other way indicates recovery. The MCMCglmm package was used to estimate breeding values. In the 60 daughters...

  20. Longitudinal Assessment of Left Ventricular Mass in Autosomal Dominant Polycystic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Taimur Dad

    2018-05-01

    Full Text Available Introduction: The high burden of cardiovascular morbidity and mortality in autosomal dominant polycystic kidney disease (ADPKD is related to development of hypertension and left ventricular hypertrophy. Blood pressure reduction has been shown to reduce left ventricular mass in ADPKD; however, moderators and predictors of response to lower blood pressure are unknown. Methods: This was a post hoc cohort analysis of HALT PKD study A, a randomized placebo controlled trial examining the effect of low blood pressure and single versus dual renin−angiotensin blockade in early ADPKD. Participants were hypertensive ADPKD patients 15 to 49 years of age with estimated glomerular filtration rate (eGFR > 60 ml/min per 1.73 m2 across 7 centers in the United States. Predictors included age, sex, baseline eGFR, systolic blood pressure, total kidney volume, serum potassium, and urine sodium, potassium, albumin, and aldosterone. Outcome was left ventricular mass index (LVMI measured using 1.5-T magnetic resonance imaging at months 0, 24, 48, and 60. Results: Reduction in LVMI was associated with higher baseline systolic blood pressure and larger kidney volume regardless of blood pressure control group assignment (P < 0.001 for both. Male sex and baseline eGFR were associated with a positive annual slope in LVMI (P < 0.001 and P = 0.07, respectively. Conclusion: Characteristics associated with higher risk of progression in ADPKD, including higher systolic blood pressure, larger kidney volume, and lower eGFR are associated with improvement in LVMI with intensive blood pressure control, whereas male sex is associated with a smaller slope of reduction in LVMI. Keywords: autosomal dominant polycystic kidney disease, hypertension, left ventricular hypertrophy, left ventricular mass index

  1. Longitudinal analysis of progression in glaucoma using spectral-domain optical coherence tomography.

    Science.gov (United States)

    Wessel, Julia M; Horn, Folkert K; Tornow, Ralf P; Schmid, Matthias; Mardin, Christian Y; Kruse, Friedrich E; Juenemann, Anselm G; Laemmer, Robert

    2013-05-01

    To compare the longitudinal loss of RNFL thickness measurements by SD-OCT in healthy individuals and glaucoma patients with or without progression concerning optic disc morphology. A total of 62 eyes, comprising 38 glaucomatous eyes with open angle glaucoma and 24 healthy controls, were included in the study (Erlangen Glaucoma Registry, NTC00494923). All patients were investigated annually over a period of 3 years by Spectralis SD-OCT measuring peripapillary RNFL thickness. By masked comparative analysis of photographs, the eyes were classified into nonprogressive and progressive glaucoma cases. Longitudinal loss of RNFL thickness was compared with morphological changes of optic disc morphology. Mixed model analysis of annual OCT scans revealed an estimated annual decrease of the RNFL thickness by 2.12 μm in glaucoma eyes with progression, whereas glaucoma eyes without progression in optic disc morphology lost 1.18 μm per year in RNFL thickness (P = 0.002). The rate of change in healthy eyes was 0.60 μm and thereby also significantly lower than in glaucoma eyes with progression (P < 0.001). The intrasession variability of three successive measurements without head repositioning was 1.5 ± 0.7 μm. The loss of mean RNFL thickness exceeded the intrasession variability in 60% of nonprogressive eyes, and in 85% of progressive eyes after 3 years. LONGITUDINAL MEASUREMENTS OF RNFL THICKNESS USING SD-OCT SHOW A MORE PRONOUNCED REDUCTION OF RNFL THICKNESS IN PATIENTS WITH PROGRESSION COMPARED WITH PATIENTS WITHOUT PROGRESSION IN GLAUCOMATOUS OPTIC DISC CHANGES. (www.clinicaltrials.gov number, NTC00494923.).

  2. Frequency, prevalence, incidence and risk factors associated with visual hallucinations in a sample of patients with Parkinson's disease: a longitudinal 4-year study.

    Science.gov (United States)

    Gibson, G; Mottram, P G; Burn, D J; Hindle, J V; Landau, S; Samuel, M; Hurt, C S; Brown, R G; M Wilson, K C

    2013-06-01

    To examine the prevalence, incidence and risk factors associated with visual hallucinations (VHs) amongst people suffering from Parkinson's disease (PD). We recruited 513 patients with PD from movement disorder and PD clinics within three sites in the UK. Patients were interviewed using a series of standardised clinical rating scales at baseline, 12, 24 and 36 months. Data relating to VHs were collected using the North-East Visual Hallucinations Interview. Prevalence rates for VHs at each assessment were recorded. Associations were determined using multiple regression analysis. Cross-sectional prevalence rates for VHs at baseline, 12, 24 and 36 months indicated VHs in approximately 50% of patients. A cumulative frequency of 82.7% of cases at the end of the study period exhibited VHs. The incidence rate for VHs was 457 cases per 1000 population. Longer disease duration, greater impairment in activities of daily living and higher rates of anxiety were most commonly associated with VHs. No factors predictive of VHs could be ascertained. When examined longitudinally, VHs affect more patients than is commonly assumed in cross-sectional prevalence studies. Clinicians should routinely screen for VHs throughout the disease course. Disease duration, impairment in activities of daily living and anxiety presented as co-morbidities associated with VHs in PD, and therefore those presenting with VHs should be screened for anxiety disorder and vice versa. Copyright © 2012 John Wiley & Sons, Ltd.

  3. Longitudinal Patterns of Change in Systolic Blood Pressure and Incidence of Cardiovascular Disease: The Atherosclerosis Risk in Communities Study.

    Science.gov (United States)

    Petruski-Ivleva, Natalia; Viera, Anthony J; Shimbo, Daichi; Muntner, Paul; Avery, Christy L; Schneider, Andrea L C; Couper, David; Kucharska-Newton, Anna

    2016-06-01

    Elevated blood pressure in midlife contributes significantly to the risk of cardiovascular disease. However, patterns of blood pressure increase may differ among individuals and may result in differential risk. Our goal was to examine the contribution of longitudinal patterns of blood pressure change to incidence of heart failure, coronary heart disease, stroke, and cardiovascular disease mortality. Latent class growth models were used to identify patterns of change in blood pressure across 4 clinical examinations (1987-1998) among 9845 Atherosclerosis Risk in Communities (ARIC) cohort participants (mean age, 53.7 [SD 5.7] years). Patterns of change in systolic blood pressure included slowly and steeply increasing, a decreasing and a sustained elevated blood pressure. Changes in diastolic and mid-blood pressure (½ systolic+½ diastolic) were less pronounced. The association of blood pressure pattern group membership with incidence of clinical outcomes was examined in follow-up from the fourth clinical examination (1996-1998) to December 31, 2011, using Poisson regression models adjusted for demographic and metabolic characteristics, and hypertension medication use. A gradient of rates of all events was observed across the identified patterns. Associations were attenuated after adjustment for covariates. Cumulative systolic blood pressure load, rather than the temporal pattern of change in systolic blood pressure itself, plays a role in determining the risk of cardiovascular disease, in particular, of heart failure and cardiovascular disease mortality, independent of blood pressure level measured at one point in time. © 2016 American Heart Association, Inc.

  4. Pooling Data from Multiple Longitudinal Studies: The Role of Item Response Theory in Integrative Data Analysis

    Science.gov (United States)

    Curran, Patrick J.; Hussong, Andrea M.; Cai, Li; Huang, Wenjing; Chassin, Laurie; Sher, Kenneth J.; Zucker, Robert A.

    2010-01-01

    There are a number of significant challenges encountered when studying development over an extended period of time including subject attrition, changing measurement structures across group and developmental period, and the need to invest substantial time and money. Integrative data analysis is an emerging set of methodologies that overcomes many of the challenges of single sample designs through the pooling of data drawn from multiple existing developmental studies. This approach is characterized by a host of advantages, but this also introduces several new complexities that must be addressed prior to broad adoption by developmental researchers. In this paper we focus on methods for fitting measurement models and creating scale scores using data drawn from multiple longitudinal studies. We present findings from the analysis of repeated measures of internalizing symptomatology that were pooled from three existing developmental studies. We describe and demonstrate each step in the analysis and we conclude with a discussion of potential limitations and directions for future research. PMID:18331129

  5. Patient safety in the clinical laboratory: a longitudinal analysis of specimen identification errors.

    Science.gov (United States)

    Wagar, Elizabeth A; Tamashiro, Lorraine; Yasin, Bushra; Hilborne, Lee; Bruckner, David A

    2006-11-01

    Patient safety is an increasingly visible and important mission for clinical laboratories. Attention to improving processes related to patient identification and specimen labeling is being paid by accreditation and regulatory organizations because errors in these areas that jeopardize patient safety are common and avoidable through improvement in the total testing process. To assess patient identification and specimen labeling improvement after multiple implementation projects using longitudinal statistical tools. Specimen errors were categorized by a multidisciplinary health care team. Patient identification errors were grouped into 3 categories: (1) specimen/requisition mismatch, (2) unlabeled specimens, and (3) mislabeled specimens. Specimens with these types of identification errors were compared preimplementation and postimplementation for 3 patient safety projects: (1) reorganization of phlebotomy (4 months); (2) introduction of an electronic event reporting system (10 months); and (3) activation of an automated processing system (14 months) for a 24-month period, using trend analysis and Student t test statistics. Of 16,632 total specimen errors, mislabeled specimens, requisition mismatches, and unlabeled specimens represented 1.0%, 6.3%, and 4.6% of errors, respectively. Student t test showed a significant decrease in the most serious error, mislabeled specimens (P patient safety projects. Trend analysis demonstrated decreases in all 3 error types for 26 months. Applying performance-improvement strategies that focus longitudinally on specimen labeling errors can significantly reduce errors, therefore improving patient safety. This is an important area in which laboratory professionals, working in interdisciplinary teams, can improve safety and outcomes of care.

  6. Micro-Mechanical Analysis About Kink Band in Carbon Fiber/Epoxy Composites Under Longitudinal Compression

    Science.gov (United States)

    Zhang, Mi; Guan, Zhidong; Wang, Xiaodong; Du, Shanyi

    2017-10-01

    Kink band is a typical phenomenon for composites under longitudinal compression. In this paper, theoretical analysis and finite element simulation were conducted to analyze kink angle as well as compressive strength of composites. Kink angle was considered to be an important character throughout longitudinal compression process. Three factors including plastic matrix, initial fiber misalignment and rotation due to loading were considered for theoretical analysis. Besides, the relationship between kink angle and fiber volume fraction was improved and optimized by theoretical derivation. In addition, finite element models considering fiber stochastic strength and Drucker-Prager constitutive model for matrix were conducted in ABAQUS to analyze kink band formation process, which corresponded with the experimental results. Through simulation, the loading and failure procedure can be evidently divided into three stages: elastic stage, softening stage, and fiber break stage. It also shows that kink band is a result of fiber misalignment and plastic matrix. Different values of initial fiber misalignment angle, wavelength and fiber volume fraction were considered to explore the effects on compressive strength and kink angle. Results show that compressive strength increases with the decreasing of initial fiber misalignment angle, the decreasing of initial fiber misalignment wavelength and the increasing of fiber volume fraction, while kink angle decreases in these situations. Orthogonal array in statistics was also built to distinguish the effect degree of these factors. It indicates that initial fiber misalignment angle has the largest impact on compressive strength and kink angle.

  7. Genome-Wide Meta-Analysis of Longitudinal Alcohol Consumption Across Youth and Early Adulthood.

    Science.gov (United States)

    Adkins, Daniel E; Clark, Shaunna L; Copeland, William E; Kennedy, Martin; Conway, Kevin; Angold, Adrian; Maes, Hermine; Liu, Youfang; Kumar, Gaurav; Erkanli, Alaattin; Patkar, Ashwin A; Silberg, Judy; Brown, Tyson H; Fergusson, David M; Horwood, L John; Eaves, Lindon; van den Oord, Edwin J C G; Sullivan, Patrick F; Costello, E J

    2015-08-01

    The public health burden of alcohol is unevenly distributed across the life course, with levels of use, abuse, and dependence increasing across adolescence and peaking in early adulthood. Here, we leverage this temporal patterning to search for common genetic variants predicting developmental trajectories of alcohol consumption. Comparable psychiatric evaluations measuring alcohol consumption were collected in three longitudinal community samples (N=2,126, obs=12,166). Consumption-repeated measurements spanning adolescence and early adulthood were analyzed using linear mixed models, estimating individual consumption trajectories, which were then tested for association with Illumina 660W-Quad genotype data (866,099 SNPs after imputation and QC). Association results were combined across samples using standard meta-analysis methods. Four meta-analysis associations satisfied our pre-determined genome-wide significance criterion (FDR<0.1) and six others met our 'suggestive' criterion (FDR<0.2). Genome-wide significant associations were highly biological plausible, including associations within GABA transporter 1, SLC6A1 (solute carrier family 6, member 1), and exonic hits in LOC100129340 (mitofusin-1-like). Pathway analyses elaborated single marker results, indicating significant enriched associations to intuitive biological mechanisms, including neurotransmission, xenobiotic pharmacodynamics, and nuclear hormone receptors (NHR). These findings underscore the value of combining longitudinal behavioral data and genome-wide genotype information in order to study developmental patterns and improve statistical power in genomic studies.

  8. Hearing Impairment Affects Dementia Incidence. An Analysis Based on Longitudinal Health Claims Data in Germany

    Science.gov (United States)

    Teipel, Stefan; Óvári, Attila; Kilimann, Ingo; Witt, Gabriele; Doblhammer, Gabriele

    2016-01-01

    Recent research has revealed an association between hearing impairment and dementia. The objective of this study is to determine the effect of hearing impairment on dementia incidence in a longitudinal study, and whether ear, nose, and throat (ENT) specialist care, care level, institutionalization, or depression mediates or moderates this pathway. The present study used a longitudinal sample of 154,783 persons aged 65 and older from claims data of the largest German health insurer; containing 14,602 incident dementia diagnoses between 2006 and 2010. Dementia and hearing impairment diagnoses were defined according to International Classification of Diseases, Tenth Revision, codes. We used a Kaplan Meier estimator and performed Cox proportional hazard models to explore the effect of hearing impairment on dementia incidence, controlling for ENT specialist care, care level, institutionalization, and depression. Gender, age, and comorbidities were controlled for as potential confounders. Patients with bilateral (HR = 1.43, pimpairment had higher risks of dementia incidence than patients without hearing impairment. We found no significant effect for unilateral hearing impairment and other diseases of the ear. The effect of hearing impairment was only partly mediated through ENT specialist utilization. Significant interaction between hearing impairment and specialist care, care level, and institutionalization, respectively, indicated moderating effects. We discuss possible explanations for these effects. This study underlines the importance of the association between hearing impairment and dementia. Preserving hearing ability may maintain social participation and may reduce the burden associated with dementia. The particular impact of hearing aid use should be the subject of further investigations, as it offers potential intervention on the pathway to dementia. PMID:27391486

  9. Depression as a risk factor for dementia and mild cognitive impairment: a meta-analysis of longitudinal studies.

    Science.gov (United States)

    Gao, Yuan; Huang, Changquan; Zhao, Kexiang; Ma, Louyan; Qiu, Xuan; Zhang, Lei; Xiu, Yun; Chen, Lin; Lu, Wei; Huang, Chunxia; Tang, Yong; Xiao, Qian

    2013-05-01

    This study examined whether depression was a risk factor for onset of dementia including Alzheimer's disease (AD), vascular dementia (VD) and any dementia, and mild cognitive impairment (MCI) by using a quantitative meta-analysis of longitudinal studies. EMBASE and MEDLINE were searched for articles published up to February 2011. All studies that examined the relationship between depression and the onset of dementia or MCI were included. Pooled relative risk was calculated using fixed-effects models. Twelve studies met our inclusion criteria for this meta-analysis. All subjects were without dementia or MCI at baseline. Four, two, five, and four studies compared the incidence of AD, VD, any dementia, and MCI between subjects with or without depression, respectively. After pooling all the studies, subjects with depression had higher incidence of AD (relative risk (RR):1.66, 95% confidence interval (CI): 1.29-2.14), VD (RR: 1.89, 95% CI: 1.19-3.01), any dementia (RR: 1.55, 95% CI: 1.31-2.83), and MCI (RR: 1.97, 95% CI: 1.53-2.54) than those without depression. The quantitative meta-analysis showed that depression was a major risk factor for incidence of dementia (including AD, VD, and any dementia) and MCI. Copyright © 2012 John Wiley & Sons, Ltd.

  10. Quantitative muscle MRI as an assessment tool for monitoring disease progression in LGMD2I: a multicentre longitudinal study.

    Directory of Open Access Journals (Sweden)

    Tracey A Willis

    Full Text Available Outcome measures for clinical trials in neuromuscular diseases are typically based on physical assessments which are dependent on patient effort, combine the effort of different muscle groups, and may not be sensitive to progression over short trial periods in slow-progressing diseases. We hypothesised that quantitative fat imaging by MRI (Dixon technique could provide more discriminating quantitative, patient-independent measurements of the progress of muscle fat replacement within individual muscle groups.To determine whether quantitative fat imaging could measure disease progression in a cohort of limb-girdle muscular dystrophy 2I (LGMD2I patients over a 12 month period.32 adult patients (17 male;15 female from 4 European tertiary referral centres with the homozygous c.826C>A mutation in the fukutin-related protein gene (FKRP completed baseline and follow up measurements 12 months later. Quantitative fat imaging was performed and muscle fat fraction change was compared with (i muscle strength and function assessed using standardized physical tests and (ii standard T1-weighted MRI graded on a 6 point scale.There was a significant increase in muscle fat fraction in 9 of the 14 muscles analyzed using the quantitative MRI technique from baseline to 12 months follow up. Changes were not seen in the conventional longitudinal physical assessments or in qualitative scoring of the T₁w images.Quantitative muscle MRI, using the Dixon technique, could be used as an important longitudinal outcome measure to assess muscle pathology and monitor therapeutic efficacy in patients with LGMD2I.

  11. The oral microbiota of Irish children in health and disease: a longitudinal and cross sectional study

    OpenAIRE

    Hurley, Eimear

    2017-01-01

    The oral cavity harbours a very rich and diverse microbial community. In the last decade, the oral microbiota of children and adults has been studied in detail using continuously developing DNA sequencing methods. In particular focusing on the oral microbiome changes in the presence of diseases such as dental caries, periodontal disease and the relationship of the oral microbiome with oral health and disease states. The overall aim of these studies was to unravel the complexity of the oral ec...

  12. The Latent Curve ARMA (P, Q) Panel Model: Longitudinal Data Analysis in Educational Research and Evaluation

    Science.gov (United States)

    Sivo, Stephen; Fan, Xitao

    2008-01-01

    Autocorrelated residuals in longitudinal data are widely reported as common to longitudinal data. Yet few, if any, researchers modeling growth processes evaluate a priori whether their data have this feature. Sivo, Fan, and Witta (2005) found that not modeling autocorrelated residuals present in longitudinal data severely biases latent curve…

  13. Regression analysis of longitudinal data with correlated censoring and observation times.

    Science.gov (United States)

    Li, Yang; He, Xin; Wang, Haiying; Sun, Jianguo

    2016-07-01

    Longitudinal data occur in many fields such as the medical follow-up studies that involve repeated measurements. For their analysis, most existing approaches assume that the observation or follow-up times are independent of the response process either completely or given some covariates. In practice, it is apparent that this may not be true. In this paper, we present a joint analysis approach that allows the possible mutual correlations that can be characterized by time-dependent random effects. Estimating equations are developed for the parameter estimation and the resulted estimators are shown to be consistent and asymptotically normal. The finite sample performance of the proposed estimators is assessed through a simulation study and an illustrative example from a skin cancer study is provided.

  14. Longitudinal analysis of categorical epidemiological data: a study of Three Mile Island.

    Science.gov (United States)

    Fienberg, S E; Bromet, E J; Follmann, D; Lambert, D; May, S M

    1985-11-01

    The accident at the Three Mile Island nuclear power plant in 1979 led to an unprecedented set of events with potentially life threatening implications. This paper focusses on the analysis of a longitudinal study of the psychological well-being of the mothers of young children living within 10 miles of the plant. The initial analyses of the data utilize loglinear/logit model techniques from the contingency table literature, and involve the fitting of a sequence of logit models. The inadequancies of these analyses are noted, and a new class of mixture models for logistic response structures is introduced to overcome the noted shortcomings. The paper includes a brief outline of the methodology relevant for the fitting of these models using the method of maximum likelihood, and then the model is applied to the TMI data. The paper concludes with a discussion of some of the substantive implications of the mixture model analysis.

  15. Childhood trauma and suicide attempt: A meta-analysis of longitudinal studies from the last decade.

    Science.gov (United States)

    Zatti, Cleonice; Rosa, Virgínia; Barros, Alcina; Valdivia, Lucianne; Calegaro, Vitor Crestani; Freitas, Lúcia Helena; Ceresér, Keila Maria Mendes; Rocha, Neusa Sica da; Bastos, Andre Goettems; Schuch, Felipe Barreto

    2017-10-01

    Childhood trauma (CT) is a modifiable risk factor for lifetime suicide attempts (SA). However, the extent to which each type of CT increases SA risk is unclear. This study aimed to conduct a meta-analysis of longitudinal studies published in the last 10 years about the relationship between CT and lifetime SA risk. The PUBMED, PsycINFO, ISI, and EMBASE databases were searched for cohort studies that reported AS during follow-up and included an assessment of CT. A meta-analysis was conducted to identify potential effects of each type of CT on SA. Seven unique studies were included for review. Sexual (n=6, OR=3.73, 95%CI 2.94-4.75, pbroken home were not significantly associated with further SA. The modes of CT that most contribute to SA in later life are physical, emotional, and sexual abuse and physical neglect, in descending order. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Accuracy and Uncertainty Analysis of Intelligent Techniques for Predicting the Longitudinal Dispersion Coefficient in Rivers

    Directory of Open Access Journals (Sweden)

    Abbas Akbarzadeh

    2010-09-01

    Full Text Available Accurate prediction of longitudinal dispersion coefficient (LDC can be useful for the determination of pollutants concentration distribution in natural rivers. However, the uncertainty associated with the results obtained from forecasting models has a negative effect on pollutant management in water resources. In this research, appropriate models are first developed using ANN and ANFIS techniques to predict the LDC in natural streams. Then, an uncertainty analysis is performed for ANN and ANFIS models based on Monte-Carlo simulation. The input parameters of the models are related to hydraulic variables and stream geometry. Results indicate that ANN is a suitable model for predicting the LDC, but it is also associated with a high level of uncertainty. However, results of uncertainty analysis show that ANFIS model has less uncertainty; i.e. it is the best model for forecasting satisfactorily the LDC in natural streams.

  17. Self-concept and academic achievement: a meta-analysis of longitudinal relations.

    Science.gov (United States)

    Huang, Chiungjung

    2011-10-01

    The relation between self-concept and academic achievement was examined in 39 independent and longitudinal samples through the integration of meta-analysis and path analysis procedures. For relations with more than 3 independent samples, the mean observed correlations ranged from .20 to .27 between prior self-concept and subsequent academic achievement and from .19 to .25 between prior academic achievement and subsequent self-concept. Globality/specificity of self-concept was the only significant moderating factor in the relation between (a) prior self-concept and subsequent academic achievement and (b) prior academic achievement and subsequent self-concept. As high self-concept is related to high academic performance and vice-versa, intervention programs that combine self-enhancement and skill development should be integrated. Copyright © 2011 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

  18. Mapping longitudinal scientific progress, collaboration and impact of the Alzheimer's disease neuroimaging initiative.

    Directory of Open Access Journals (Sweden)

    Xiaohui Yao

    Full Text Available Alzheimer's disease neuroimaging initiative (ADNI is a landmark imaging and omics study in AD. ADNI research literature has increased substantially over the past decade, which poses challenges for effectively communicating information about the results and impact of ADNI-related studies. In this work, we employed advanced information visualization techniques to perform a comprehensive and systematic mapping of the ADNI scientific growth and impact over a period of 12 years.Citation information of ADNI-related publications from 01/01/2003 to 05/12/2015 were downloaded from the Scopus database. Five fields, including authors, years, affiliations, sources (journals, and keywords, were extracted and preprocessed. Statistical analyses were performed on basic publication data as well as journal and citations information. Science mapping workflows were conducted using the Science of Science (Sci2 Tool to generate geospatial, topical, and collaboration visualizations at the micro (individual to macro (global levels such as geospatial layouts of institutional collaboration networks, keyword co-occurrence networks, and author collaboration networks evolving over time.During the studied period, 996 ADNI manuscripts were published across 233 journals and conference proceedings. The number of publications grew linearly from 2008 to 2015, so did the number of involved institutions. ADNI publications received much more citations than typical papers from the same set of journals. Collaborations were visualized at multiple levels, including authors, institutions, and research areas. The evolution of key ADNI research topics was also plotted over the studied period.Both statistical and visualization results demonstrate the increasing attention of ADNI research, strong citation impact of ADNI publications, the expanding collaboration networks among researchers, institutions and ADNI core areas, and the dynamic evolution of ADNI research topics. The visualizations

  19. Periodontal Pocket Depth, Hyperglycemia, and Progression of Chronic Kidney Disease: A Population-Based Longitudinal Study.

    Science.gov (United States)

    Chang, Jia-Feng; Yeh, Jih-Chen; Chiu, Ya-Lin; Liou, Jian-Chiun; Hsiung, Jing-Ru; Tung, Tao-Hsin

    2017-01-01

    No large epidemiological study has been conducted to investigate the interaction and joint effects of periodontal pocket depth and hyperglycemia on progression of chronic kidney disease in patients with periodontal diseases. Periodontal pocket depth was utilized for the grading severity of periodontal disease in 2831 patients from January 2002 to June 2013. Progression of chronic kidney disease was defined as progression of color intensity in glomerular filtration rate and albuminuria grid of updated Kidney Disease-Improving Global Outcomes guidelines. Multivariable-adjusted hazard ratios (aHR) in various models were presented across different levels of periodontal pocket depth and hemoglobin A1c (HbA1c) in forest plots and 3-dimensional histograms. During 7621 person-years of follow-up, periodontal pocket depth and HbA1C levels were robustly associated with incremental risks for progression of chronic kidney disease (aHR 3.1; 95% confidence interval [CI], 2.0-4.6 for periodontal pocket depth >4.5 mm, and 2.5; 95% CI, 1.1-5.4 for HbA1C >6.5%, respectively). The interaction between periodontal pocket depth and HbA1C on progression of chronic kidney disease was strong (P periodontal pocket depth (>4.5 mm) and higher HbA1C (>6.5%) had the greatest risk (aHR 4.2; 95% CI, 1.7-6.8) compared with the lowest aHR group (periodontal pocket depth ≤3.8 mm and HbA1C ≤6%). Our study identified combined periodontal pocket depth and HbA1C as a valuable predictor of progression of chronic kidney disease in patients with periodontal diseases. While considering the interaction between periodontal diseases and hyperglycemia, periodontal survey and optimizing glycemic control are warranted to minimize the risk of worsening renal function. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Does oral language underpin the development of later behavior problems? A longitudinal meta-analysis.

    Science.gov (United States)

    Chow, Jason C; Ekholm, Erik; Coleman, Heather

    2018-05-24

    The purpose of this article is to estimate the overall weighted mean effect of the relation between early language skills and later behavior problems in school-aged children. A systematic literature search yielded 19,790 unduplicated reports, and a structured search strategy and identification procedure yielded 25 unique data sets, with 114 effect sizes for analysis. Eligible reports were then coded, and effect sizes were extracted and synthesized via robust variance estimation and random-effects meta-analytic techniques. The overall correlation between early language and later behavior problems was negative and small (r = -.14, 95% confidence interval [CI] [-.16, -.11]), and controlling for demographic variables did not reduce the magnitude of the inverse relationship between language skill and problem behavior (r = -.16). Moderator analyses identified receptive language, parent-reported behavior measures, gender, and age as significant predictors of the association between language and behavior. This article corroborates the consistent findings of previous meta-analytic and longitudinal studies and further identifies areas, particularly around measurement, for future research. Furthermore, prospective longitudinal evaluations of the relations between language deficits and behavior problems with different types of measures (teacher-/parent-report, direct assessment, classroom observation) is warranted. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  1. Normative changes in interests from adolescence to adulthood: A meta-analysis of longitudinal studies.

    Science.gov (United States)

    Hoff, Kevin A; Briley, Daniel A; Wee, Colin J M; Rounds, James

    2018-04-01

    Vocational interests predict a variety of important outcomes and are among the most widely applied individual difference constructs in psychology and education. Despite over 90 years of research, little is known about the longitudinal development of interests. In this meta-analysis, the authors investigate normative changes in interests through adolescence and young adulthood. Effect sizes were aggregated from 49 longitudinal studies reporting mean-level changes in vocational interests, containing 98 total samples and 20,639 participants. Random effects meta-analytic regression models were used to assess age-related changes and gender differences across Holland's (1959, 1997) RIASEC categories and composite dimensions (people, things, data, and ideas). Results showed that mean-level interest scores generally increase with age, but effect sizes varied across interest categories and developmental periods. Adolescence was defined by two broad patterns of change: interest scores generally decreased during early adolescence, but then increased during late adolescence. During young adulthood, the most striking changes were found across the people and things orientations. Interests involving people tended to increase (artistic, social, and enterprising), whereas interests involving things either decreased (conventional) or remained constant (realistic and investigative). Gender differences associated with occupational stereotypes reached a lifetime peak during early adolescence, then tended to decrease in all subsequent age periods. Overall findings suggest there are normative changes in vocational interests from adolescence to adulthood, with important implications for developmental theories and the applied use of interests. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  2. Social Activity and Cognitive Functioning Over Time: A Coordinated Analysis of Four Longitudinal Studies

    Directory of Open Access Journals (Sweden)

    Cassandra L. Brown

    2012-01-01

    Full Text Available Social activity is typically viewed as part of an engaged lifestyle that may help mitigate the deleterious effects of advanced age on cognitive function. As such, social activity has been examined in relation to cognitive abilities later in life. However, longitudinal evidence for this hypothesis thus far remains inconclusive. The current study sought to clarify the relationship between social activity and cognitive function over time using a coordinated data analysis approach across four longitudinal studies. A series of multilevel growth models with social activity included as a covariate is presented. Four domains of cognitive function were assessed: reasoning, memory, fluency, and semantic knowledge. Results suggest that baseline social activity is related to some, but not all, cognitive functions. Baseline social activity levels failed to predict rate of decline in most cognitive abilities. Changes in social activity were not consistently associated with cognitive functioning. Our findings do not provide consistent evidence that changes in social activity correspond to immediate benefits in cognitive functioning, except perhaps for verbal fluency.

  3. Exposure to violent video games and aggression in German adolescents: a longitudinal analysis.

    Science.gov (United States)

    Möller, Ingrid; Krahé, Barbara

    2009-01-01

    The relationship between exposure to violent electronic games and aggressive cognitions and behavior was examined in a longitudinal study. A total of 295 German adolescents completed the measures of violent video game usage, endorsement of aggressive norms, hostile attribution bias, and physical as well as indirect/relational aggression cross-sectionally, and a subsample of N=143 was measured again 30 months later. Cross-sectional results at T1 showed a direct relationship between violent game usage and aggressive norms, and an indirect link to hostile attribution bias through aggressive norms. In combination, exposure to game violence, normative beliefs, and hostile attribution bias predicted physical and indirect/relational aggression. Longitudinal analyses using path analysis showed that violence exposure at T1 predicted physical (but not indirect/relational) aggression 30 months later, whereas aggression at T1 was unrelated to later video game use. Exposure to violent games at T1 influenced physical (but not indirect/relational) aggression at T2 via an increase of aggressive norms and hostile attribution bias. The findings are discussed in relation to social-cognitive explanations of long-term effects of media violence on aggression. Copyright 2008 Wiley-Liss, Inc.

  4. The Mutual Relationship Between Men's Drinking and Depression: A 4-Year Longitudinal Analysis.

    Science.gov (United States)

    Lee, Soo Bi; Chung, Sulki; Lee, HaeKook; Seo, Jeong Seok

    2018-03-17

    The purpose of the current study was to examine the longitudinal reciprocal relationship between depression and drinking among male adults from the general population. This study used a panel dataset from the Korean Welfare Panel (from 2011 to 2014). The subjects were 2511 male adults aged between 20 and 65 years. Based on the Korean Version of the Alcohol Use Disorders Identification Test (AUDIT-K) scores, 2191 subjects were categorized as the control group (AUDIT-K AUDIT-K ≥ 12). An autoregressive cross-lagged modelling analysis was performed to investigate the mutual relationship between problem drinking and depression measured consecutively over time. The results indicated that alcohol drinking and depression were stable over time. In the control group, there was no significant causal relationship between problem drinking and depression while in the problem drinking group, drinking in the previous year significantly influenced depression in the following second, third and fourth years. This study compared normal versus problem drinkers and showed a 4-year mutual causal relationship between depression and drinking. No longitudinal interaction between drinking and depression occurred in normal drinkers, while drinking intensified depression over time in problem drinkers. This study found that problem drinking was a risk factor for development of depression. Therefore, more attention should be given to problem alcohol use in the general population and evaluation of past alcohol use history in patients with depressive disorders.

  5. Substance abuse and quality of life among severely mentally ill consumers: a longitudinal modelling analysis.

    Science.gov (United States)

    Urbanoski, Karen A; Cairney, John; Adlaf, Edward; Rush, Brian

    2007-10-01

    Evidence suggests that substance abuse negatively affects both psychiatric symptom severity and quality of life (QOL) in people with severe mental illness (SMI). However, these relationships have not been examined simultaneously, nor have they been characterized over time. Thus, it is difficult to appreciate the extent to which substance abuse exerts an enduring effect on psychiatric symptoms and distress and/or QOL in this population. The purpose of this study is to test a conceptual model linking these factors together. Subjects were participants in a longitudinal evaluation of community mental healthcare in Ontario (n = 133). Comprehensive consumer assessments were conducted at treatment entry, and at 9 and 18 months. Subjects were receiving intensive case management or assertive community treatment throughout the 18-month study period. Structural equation modelling was used to examine the concurrent and longitudinal relationships between substance abuse, symptoms and distress, and QOL. The prevalence of substance abuse was 55.0%. The SEM analysis suggested that substance abuse at baseline was associated with elevated symptomatology and distress and lower QOL, and that these effects endured after 18 months of treatment. Psychiatric symptoms and distress mediated the negative relationship between substance abuse and QOL. The mediating role played by symptom and distress levels in the relationship between substance abuse and QOL suggests the importance of closely monitoring changes in these factors among SMI patients with substance problems. Tracking symptom severity and distress levels over time will allow service providers to intervene and potentially improve the QOL of individuals with SMI.

  6. A single-level random-effects cross-lagged panel model for longitudinal mediation analysis.

    Science.gov (United States)

    Wu, Wei; Carroll, Ian A; Chen, Po-Yi

    2017-12-06

    Cross-lagged panel models (CLPMs) are widely used to test mediation with longitudinal panel data. One major limitation of the CLPMs is that the model effects are assumed to be fixed across individuals. This assumption is likely to be violated (i.e., the model effects are random across individuals) in practice. When this happens, the CLPMs can potentially yield biased parameter estimates and misleading statistical inferences. This article proposes a model named a random-effects cross-lagged panel model (RE-CLPM) to account for random effects in CLPMs. Simulation studies show that the RE-CLPM outperforms the CLPM in recovering the mean indirect and direct effects in a longitudinal mediation analysis when random effects exist in the population. The performance of the RE-CLPM is robust to a certain degree, even when the random effects are not normally distributed. In addition, the RE-CLPM does not produce harmful results when the model effects are in fact fixed in the population. Implications of the simulation studies and potential directions for future research are discussed.

  7. Drug awareness in adolescents attending a mental health service: analysis of longitudinal data.

    Science.gov (United States)

    Arnau, Jaume; Bono, Roser; Díaz, Rosa; Goti, Javier

    2011-11-01

    One of the procedures used most recently with longitudinal data is linear mixed models. In the context of health research the increasing number of studies that now use these models bears witness to the growing interest in this type of analysis. This paper describes the application of linear mixed models to a longitudinal study of a sample of Spanish adolescents attending a mental health service, the aim being to investigate their knowledge about the consumption of alcohol and other drugs. More specifically, the main objective was to compare the efficacy of a motivational interviewing programme with a standard approach to drug awareness. The models used to analyse the overall indicator of drug awareness were as follows: (a) unconditional linear growth curve model; (b) growth model with subject-associated variables; and (c) individual curve model with predictive variables. The results showed that awareness increased over time and that the variable 'schooling years' explained part of the between-subjects variation. The effect of motivational interviewing was also significant.

  8. Meta-analysis: Coeliac disease and hypertransaminasaemia.

    Science.gov (United States)

    Sainsbury, A; Sanders, D S; Ford, A C

    2011-07-01

    There may be a positive association between coeliac disease and serum hypertransaminasaemia but evidence is conflicting. To conduct a systematic review and meta-analysis to determine the prevalence of coeliac disease in adults presenting with cryptogenic serum hypertransaminasaemia and the prevalence of hypertransaminasaemia in patients with newly diagnosed coeliac disease. MEDLINE and EMBASE were searched up to August 2010. Case series and case-control studies recruiting adults with either cryptogenic hypertransaminasaemia that applied serological tests for coeliac disease and/or distal duodenal biopsy to participants or newly diagnosed biopsy-proven coeliac disease that assessed serum transaminases were eligible. The pooled prevalence of coeliac disease in individuals presenting with abnormal serum transaminases and the pooled prevalence of hypertransaminasaemia in newly diagnosed coeliac disease were calculated with 95% confidence intervals (CI). Eleven eligible studies were identified. Pooled prevalences of positive coeliac serology and biopsy-proven coeliac disease in cryptogenic hypertransaminasaemia were 6% (95% CI 3% to 10%) and 4% (95% CI 1% to 7%) respectively. Pooled prevalence of abnormal serum transaminases in newly diagnosed coeliac disease was 27% (95% CI 13% to 44%). Exclusion of gluten led to normalisation of serum transaminase levels in 63% to 90% of patients within 1 year. Undetected coeliac disease is a potential cause for cryptogenic hypertransaminasaemia in 3% to 4% of cases. More than 20% of individuals with newly diagnosed coeliac disease may have abnormal serum transaminases and these normalise on a gluten-free diet in the majority of cases. © 2011 Blackwell Publishing Ltd.

  9. A longitudinal study of gastrointestinal diseases in individuals diagnosed with infantile autism as children

    DEFF Research Database (Denmark)

    Mouridsen, Svend-Erik; Rich, B; Isager, T

    2009-01-01

    Abstract Background A number of studies have indicated a link between gastrointestinal (GI) diseases and autism spectrum disorders. Method The objective of this study was to compare the prevalence and types of GI diseases in a clinical sample of 118 individuals diagnosed as children with infantile...... autism (IA) with GI diseases in 336 matched controls from the general population, based on data from the nationwide Danish National Hospital Register (DNHR). The average observation time was 30.3 years (SD 0.4) (range 27-30 years), and mean age at the end of the observation period was 42.7 years (SD 7...

  10. Dataset of longitudinal analysis of tear cytokine levels, CD4, CD8 counts and HIV viral load in dry eye patients with HIV infection

    Directory of Open Access Journals (Sweden)

    Praveen Kumar Balne

    2017-04-01

    Full Text Available The data presented in this article shows the longitudinal analysis of tear fluid cytokine profiles, blood CD4 and CD8 counts and HIV viral load in 34 dry eye patients with HIV infection during the HAART therapy. Clinical samples were collected from HIV patients with dry eye disease at the time of presentation to the clinic (visit 1, three months (visit 2 and 6 months (visit 3 after the presentation. At each time point tear samples were evaluated for 41 cytokines using Luminex bead based multiplex assay and blood samples were tested for HIV viral load and CD4 and CD8 counts.

  11. A longitudinal analysis of prenatal exposure to methylmercury and fatty acids in the Seychelles.

    Science.gov (United States)

    Stokes-Riner, Abbie; Thurston, Sally W; Myers, Gary J; Duffy, Emeir M; Wallace, Julie; Bonham, Maxine; Robson, Paula; Shamlaye, Conrad F; Strain, J J; Watson, Gene; Davidson, Philip W

    2011-01-01

    Maternal fish consumption during pregnancy exposes the fetus simultaneously to methylmercury (MeHg) and long chain polyunsaturated fatty acids (LCPUFA). Data from the Seychelles Child Development Nutrition Study (SCDNS) showed a negative association of MeHg with child development when children were 30 months of age, only when controlling for LCPUFA. Concomitantly, n-3 LCPUFA were found to have a significant positive association only at 9 months. These findings suggest that the effects of MeHg and LCPUFA may vary with age over the first few years of life. We address this by including outcomes at two ages and adjusting for the child's age at testing. A longitudinal analysis utilizing linear mixed models was performed to assess the associations of maternal hair total mercury (THg, a biomarker for MeHg) and maternal LCPUFA with children's Bayley Scales of Infant Development Psychomotor Developmental Index (BSID-II PDI) at 9 and 30 months of age, and to determine whether these associations change over time. Data from 228 children were included. Maternal hair MeHg had a negative effect on BSID PDI, while maternal n-3 LCPUFA had a positive effect. These effects did not change significantly from 9 to 30 months in this analysis. The longitudinal analysis provides increased power for estimating the relationships of prenatal MeHg and LCPUFA exposures during child development. Significant associations of these exposures in opposite directions confirm the importance of LCPUFA in development and the need to adjust for maternal nutrition when studying prenatal MeHg exposure. Copyright © 2010 Elsevier B.V. All rights reserved.

  12. A Study of the Factors Associated with Risk for Development of Pressure Ulcers: A Longitudinal Analysis.

    Science.gov (United States)

    Thomas, Elizebeth; Vinodkumar, Sudhaya; Mathew, Silvia; Setia, Maninder Singh

    2015-01-01

    Pressure ulcers (PUs) are prevalent in hospitalized patients; they may cause clinical, psychological, and economic problems in these patients. Previous studies are cross-sectional, have used pooled data, or cox-regression models to assess the risk for developing PU. However, PU risk scores change over time and models that account for time varying variables are useful for cohort analysis of data. The present longitudinal study was conducted to compare the risk of PU between surgical and nonsurgical patients, and to evaluate the factors associated with the development of these ulcers over a period of time. We evaluated 290 hospitalized patients over a 4 months period. The main outcomes for our analysis were: (1) Score on the pressure risk assessment scale; and (2) the proportion of individuals who were at severe risk for developing PUs. We used random effects models for longitudinal analysis of the data. The mean PU score was significantly higher in the nonsurgical patients compared with surgical patients at baseline (15.23 [3.86] vs. 9.33 [4.57]; P 20 at baseline and were considered as being at high-risk for PU; the proportion was significantly higher among the nonsurgical patients compared with the surgical patients (14% vs. 4%, P = 0.003). In the adjusted models, there was no difference for severe risk for PU between surgical and nonsurgical patients (odds ratios [ORs]: 0.37, 95% confidence interval [CI]: 0.01-12.80). An additional day in the ward was associated with a significantly higher likelihood of being at high-risk for PU (OR: 1.47, 95% CI: 1.16-1.86). There were no significant differences between patients who were admitted for surgery compared with those who were not. An additional day in the ward, however, is important for developing a high-risk score for PU on the monitoring scale, and these patients require active interventions.

  13. Integration of Multilocus Genetic Risk into the Default Mode Network Longitudinal Trajectory during the Alzheimer's Disease Process.

    Science.gov (United States)

    Su, Fan; Shu, Hao; Ye, Qing; Xie, Chunming; Yuan, Baoyu; Zhang, Zhijun; Bai, Feng

    2017-01-01

    The aim of the study was to investigate the cognitive significance of the changes in default mode network (DMN) during the process of Alzheimer's disease (AD) and the genetic basis that drives the alteration. Eighty-seven subjects with mild cognitive impairment (MCI) and 131 healthy controls (HC) were employed at baseline, and they had the genetic risk scores (GRS) based on the GWAS-validated AD-related top loci. Eleven MCIs who converted to AD (c-MCIs), 32 subjects who remained stable (nc-MCIs), and 56 HCs participated in the follow-up analyses after an average of 35 months. Decreased functional connectivity (FC) within temporal cortex was identified for MCIs at baseline, which was partially determined by the GRS; moreover, compensations may occur within the frontal-parietal brain to maintain relatively intact cognition. During the follow-ups, c-MCIs exhibited more FC declines within the prefrontal-parietal lobes and parahippocampal gyrus/hippocampus than the HCs and nc-MCIs. The GRS did not significantly vary among the three groups, whereas associations were identified at risky alleles and FC declines in all AD spectra. Interestingly, the influence of APOEɛ4 varied as the disease progressed; APOEɛ4 was associated with longitudinal FC decreases only for HCs in the single variance-based analyses and deteriorated DMN integration in nc-MCIs by combining the effects of other loci. However, the GRS without APOEɛ4 predicted FC decline for converters. It is suggested that the integration of multilocus genetic risk predicted the longitudinal trajectory of DMN and may be used as a clinical strategy to track AD progression.

  14. Gratitude uniquely predicts lower depression in chronic illness populations: A longitudinal study of inflammatory bowel disease and arthritis.

    Science.gov (United States)

    Sirois, Fuschia M; Wood, Alex M

    2017-02-01

    Although gratitude has been identified as a key clinically relevant trait for improving well-being, it is understudied within medical populations. The current study addressed this gap and extended previous and limited cross-sectional research by examining the longitudinal associations of gratitude to depression in 2 chronic illness samples, arthritis and inflammatory bowel disease (IBD). Two chronic illness samples, arthritis (N = 423) and IBD (N = 427), completed online surveys at Time 1 (T1). One hundred sixty-three people with arthritis and 144 people with IBD completed the 6-month follow-up survey (T2). Depression, gratitude, illness cognitions, perceived stress, social support, and disease-related variables were assessed at T1 and T2. At T2, 57.2% of the arthritis sample and 53.4% of the IBD sample met the cut off scores for significant depression. T1 gratitude was negatively associated with depressive symptoms at T1 and T2 in both samples (rs from -.43 to -.50). Regression analyses revealed that T1 gratitude remained a significant and unique predictor of lower T2 depression after controlling for T1 depression, relevant demographic variables, illness cognitions, changes in illness-relevant variables, and another positive psychological construct, thriving, in both samples. As the first investigation of the longitudinal associations of gratitude to psychological well-being in the context of chronic illness, the current study provides important evidence for the relevance of gratitude for health-related clinical populations. Further intervention-based research is warranted to more fully understand the potential benefits of gratitude for adjustment to chronic illness. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  15. Identification and Progression of Heart Disease Risk Factors in Diabetic Patients from Longitudinal Electronic Health Records

    Directory of Open Access Journals (Sweden)

    Jitendra Jonnagaddala

    2015-01-01

    Full Text Available Heart disease is the leading cause of death worldwide. Therefore, assessing the risk of its occurrence is a crucial step in predicting serious cardiac events. Identifying heart disease risk factors and tracking their progression is a preliminary step in heart disease risk assessment. A large number of studies have reported the use of risk factor data collected prospectively. Electronic health record systems are a great resource of the required risk factor data. Unfortunately, most of the valuable information on risk factor data is buried in the form of unstructured clinical notes in electronic health records. In this study, we present an information extraction system to extract related information on heart disease risk factors from unstructured clinical notes using a hybrid approach. The hybrid approach employs both machine learning and rule-based clinical text mining techniques. The developed system achieved an overall microaveraged F-score of 0.8302.

  16. Asthma characteristics and biomarkers from the Airways Disease Endotyping for Personalized Therapeutics (ADEPT) longitudinal profiling study

    DEFF Research Database (Denmark)

    Silkoff, P E; Strambu, I; Laviolette, M

    2015-01-01

    BACKGROUND: Asthma is a heterogeneous disease and development of novel therapeutics requires an understanding of pathophysiologic phenotypes. The purpose of the ADEPT study was to correlate clinical features and biomarkers with molecular characteristics, by profiling asthma (NCT01274507). This re...

  17. Large-scale identification of clinical and genetic predictors of motor progression in patients with newly diagnosed Parkinson's disease: a longitudinal cohort study and validation.

    Science.gov (United States)

    Latourelle, Jeanne C; Beste, Michael T; Hadzi, Tiffany C; Miller, Robert E; Oppenheim, Jacob N; Valko, Matthew P; Wuest, Diane M; Church, Bruce W; Khalil, Iya G; Hayete, Boris; Venuto, Charles S

    2017-11-01

    Better understanding and prediction of progression of Parkinson's disease could improve disease management and clinical trial design. We aimed to use longitudinal clinical, molecular, and genetic data to develop predictive models, compare potential biomarkers, and identify novel predictors for motor progression in Parkinson's disease. We also sought to assess the use of these models in the design of treatment trials in Parkinson's disease. A Bayesian multivariate predictive inference platform was applied to data from the Parkinson's Progression Markers Initiative (PPMI) study (NCT01141023). We used genetic data and baseline molecular and clinical variables from patients with Parkinson's disease and healthy controls to construct an ensemble of models to predict the annual rate of change in combined scores from the Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) parts II and III. We tested our overall explanatory power, as assessed by the coefficient of determination (R 2 ), and replicated novel findings in an independent clinical cohort from the Longitudinal and Biomarker Study in Parkinson's disease (LABS-PD; NCT00605163). The potential utility of these models for clinical trial design was quantified by comparing simulated randomised placebo-controlled trials within the out-of-sample LABS-PD cohort. 117 healthy controls and 312 patients with Parkinson's disease from the PPMI study were available for analysis, and 317 patients with Parkinson's disease from LABS-PD were available for validation. Our model ensemble showed strong performance within the PPMI cohort (five-fold cross-validated R 2 41%, 95% CI 35-47) and significant-albeit reduced-performance in the LABS-PD cohort (R 2 9%, 95% CI 4-16). Individual predictive features identified from PPMI data were confirmed in the LABS-PD cohort. These included significant replication of higher baseline MDS-UPDRS motor score, male sex, and increased age, as well as a novel Parkinson's disease

  18. Quantitative MR characterization of disease activity in the knee in children with juvenile idiopathic arthritis: a longitudinal pilot study

    International Nuclear Information System (INIS)

    Workie, Dagnachew W.; Graham, T.B.; Laor, Tal; Racadio, Judy M.; Rajagopal, Akila; O'Brien, Kendall J.; Bommer, Wendy A.; Shire, Norah J.; Dardzinski, Bernard J.

    2007-01-01

    The development of a quantifiable and noninvasive method of monitoring disease activity and response to therapy is vital for arthritis management. The purpose of this study was to investigate the utility of quantitative dynamic contrast-enhanced MRI (DCE-MRI) based on pharmacokinetic (PK) modeling to evaluate disease activity in the knee and correlate the results with the clinical assessment in children with juvenile idiopathic arthritis (JIA). A group of 17 children with JIA underwent longitudinal clinical and laboratory assessment and DCE-MRI of the knee at enrollment, 3 months, and 12 months. A PK model was employed using MRI signal enhancement data to give three parameters, K trans ' (min -1 ), k ep (min -1 ), and V p ' and to calculate synovial volume. The PK parameters, synovial volumes, and clinical and laboratory assessments in most children were significantly decreased (P < 0.05) at 12 months when compared to the enrollment values. There was excellent correlation between the PK and synovial volume and the clinical and laboratory assessments. Differences in MR and clinical parameter values in individual subjects illustrate persistent synovitis when in clinical remission. A decrease in PK parameter values obtained from DCE-MRI in children with JIA likely reflects diminution of disease activity. This technique may be used as an objective follow-up measure of therapeutic efficacy in patients with JIA. MR imaging can detect persistent synovitis in patients considered to be in clinical remission. (orig.)

  19. Recommendations to improve imaging and analysis of brain lesion load and atrophy in longitudinal studies of multiple sclerosis

    DEFF Research Database (Denmark)

    Vrenken, H; Jenkinson, M; Horsfield, M A

    2013-01-01

    resonance image analysis methods for assessing brain lesion load and atrophy, this paper makes recommendations to improve these measures for longitudinal studies of MS. Briefly, they are (1) images should be acquired using 3D pulse sequences, with near-isotropic spatial resolution and multiple image......Focal lesions and brain atrophy are the most extensively studied aspects of multiple sclerosis (MS), but the image acquisition and analysis techniques used can be further improved, especially those for studying within-patient changes of lesion load and atrophy longitudinally. Improved accuracy...

  20. Eating patterns in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil: an exploratory analysis

    Directory of Open Access Journals (Sweden)

    Letícia de Oliveira Cardoso

    2016-01-01

    Full Text Available Abstract: The food consumption of 15,071 public employees was analyzed in six Brazilian cities participating in the baseline for Brazilian Longitudinal Study of Adult Health (ELSA-Brasil, 2008-2010 with the aim of identifying eating patterns and their relationship to socio-demographic variables. Multiple correspondence and cluster analysis were applied. Four patterns were identified, with their respective frequencies: "traditional" (48%; "fruits and vegetables" (25%; "pastry shop" (24%; and "diet/light" (5% The "traditional" and "pastry shop" patterns were more frequent among men, younger individuals, and those with less schooling. "Fruits and vegetables" and "diet/light" were more frequent in women, older individuals, and those with more schooling. Our findings show the inclusion of new items in the "traditional" pattern and the appearance of the "low sugar/low fat" pattern among the eating habits of Brazilian workers, and signal socio-demographic and regional differences.

  1. Eating patterns in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil): an exploratory analysis.

    Science.gov (United States)

    Cardoso, Letícia de Oliveira; Carvalho, Marilia Sá; Cruz, Oswaldo Gonçalves; Melere, Cristiane; Luft, Vivian Cristine; Molina, Maria Del Carmen Bisi; Faria, Carolina Perim de; Benseñor, Isabela M; Matos, Sheila Maria Alvim; Fonseca, Maria de Jesus Mendes da; Griep, Rosane Harter; Chor, Dóra

    2016-01-01

    The food consumption of 15,071 public employees was analyzed in six Brazilian cities participating in the baseline for Brazilian Longitudinal Study of Adult Health (ELSA-Brasil, 2008-2010) with the aim of identifying eating patterns and their relationship to socio-demographic variables. Multiple correspondence and cluster analysis were applied. Four patterns were identified, with their respective frequencies: "traditional" (48%); "fruits and vegetables" (25%); "pastry shop" (24%); and "diet/light" (5%) The "traditional" and "pastry shop" patterns were more frequent among men, younger individuals, and those with less schooling. "Fruits and vegetables" and "diet/light" were more frequent in women, older individuals, and those with more schooling. Our findings show the inclusion of new items in the "traditional" pattern and the appearance of the "low sugar/low fat" pattern among the eating habits of Brazilian workers, and signal socio-demographic and regional differences.

  2. Power analysis on the time effect for the longitudinal Rasch model.

    Science.gov (United States)

    Feddag, M L; Blanchin, M; Hardouin, J B; Sebille, V

    2014-01-01

    Statistics literature in the social, behavioral, and biomedical sciences typically stress the importance of power analysis. Patient Reported Outcomes (PRO) such as quality of life and other perceived health measures (pain, fatigue, stress,...) are increasingly used as important health outcomes in clinical trials or in epidemiological studies. They cannot be directly observed nor measured as other clinical or biological data and they are often collected through questionnaires with binary or polytomous items. The Rasch model is the well known model in the item response theory (IRT) for binary data. The article proposes an approach to evaluate the statistical power of the time effect for the longitudinal Rasch model with two time points. The performance of this method is compared to the one obtained by simulation study. Finally, the proposed approach is illustrated on one subscale of the SF-36 questionnaire.

  3. Longitudinal behavioral analysis during dental care of children aged 0 to 3 years

    Directory of Open Access Journals (Sweden)

    Robson Frederico Cunha

    2009-09-01

    Full Text Available "When" and "how" the dentist intervenes have repercussions on children's physical and emotional patterns. The objective of the present study was to conduct a longitudinal behavioral analysis during dental care of babies aged 0 to 3 years. A total of 216 patients seen at the Baby Clinic of the School of Dentistry at Araçatuba, São Paulo State University (UNESP, were selected. The selection criterion was attendance at ten dental care sessions at bimonthly intervals for routine procedures such as clinical examination and oral hygiene. There was a predominance of cooperative behavior compared to uncooperative behavior when each visit was analyzed separately. The behavior of the patients must have been directly influenced by their psychomotor development. Constant attendance and exposure of the baby to non-stressful dental stimuli are factors that favor a cooperative behavior.

  4. The effects of work organization on the health of immigrant manual workers: A longitudinal analysis.

    Science.gov (United States)

    Arcury, Thomas A; Chen, Haiying; Mora, Dana C; Walker, Francis O; Cartwright, Michael S; Quandt, Sara A

    2016-01-01

    This analysis uses a longitudinal design to examine the associations of work organization and health outcomes among Latino manual workers. Participants included 247 Latino workers who completed baseline and 1-year follow-up interviews and clinical examinations. Health outcome measures were epicondylitis, rotator cuff syndrome, back pain, and depressive symptoms. Independent measures were measures of job demand, job control, and job support. Workers commonly experienced rotator cuff syndrome (6.5%), back pain (8.9%), and depressive symptoms (11.2%); fewer experienced epicondylitis (2.4%). Psychological demand was associated with rotator cuff syndrome; awkward position and decision latitude were associated with back pain. Decreased skill variety but increased decision latitude was associated with elevated depressive symptoms. Work context factors are important for health outcomes among vulnerable workers. Further research is needed to expand upon this work, particularly cultural perspectives on job support.

  5. Hierarchical linear modeling of longitudinal pedigree data for genetic association analysis

    DEFF Research Database (Denmark)

    Tan, Qihua; B Hjelmborg, Jacob V; Thomassen, Mads

    2014-01-01

    -effect models to explicitly model the genetic relationship. These have proved to be an efficient way of dealing with sample clustering in pedigree data. Although current algorithms implemented in popular statistical packages are useful for adjusting relatedness in the mixed modeling of genetic effects...... associated with blood pressure with estimated inflation factors of 0.99, suggesting that our modeling of random effects efficiently handles the genetic relatedness in pedigrees. Application to simulated data captures important variants specified in the simulation. Our results show that the method is useful......Genetic association analysis on complex phenotypes under a longitudinal design involving pedigrees encounters the problem of correlation within pedigrees, which could affect statistical assessment of the genetic effects. Approaches have been proposed to integrate kinship correlation into the mixed...

  6. Longitudinal data analysis in support of functional stability concepts for leachate management at closed municipal landfills

    International Nuclear Information System (INIS)

    Gibbons, Robert D.; Morris, Jeremy W.F.; Prucha, Christopher P.; Caldwell, Michael D.; Staley, Bryan F.

    2014-01-01

    Highlights: • Longitudinal data analysis using a mixed-effects regression model. • Dataset consisted of a total of 1402 samples from 101 closed municipal landfills. • Target analytes and classes generally showed predictable degradation trends. • Validates historical studies focused on macro organic indicators such as BOD. • BOD can serve as “gateway” indicator for planning leachate management. - Abstract: Landfill functional stability provides a target that supports no environmental threat at the relevant point of exposure in the absence of active control systems. With respect to leachate management, this study investigates “gateway” indicators for functional stability in terms of the predictability of leachate characteristics, and thus potential threat to water quality posed by leachate emissions. Historical studies conducted on changes in municipal solid waste (MSW) leachate concentrations over time (longitudinal analysis) have concentrated on indicator compounds, primarily chemical oxygen demand (COD) and biochemical oxygen demand (BOD). However, validation of these studies using an expanded database and larger constituent sets has not been performed. This study evaluated leachate data using a mixed-effects regression model to determine the extent to which leachate constituent degradation can be predicted based on waste age or operational practices. The final dataset analyzed consisted of a total of 1402 samples from 101 MSW landfills. Results from the study indicated that all leachate constituents exhibit a decreasing trend with time in the post-closure period, with 16 of the 25 target analytes and aggregate classes exhibiting a statistically significant trend consistent with well-studied indicators such as BOD. Decreasing trends in BOD concentration after landfill closure can thus be considered representative of trends for many leachate constituents of concern

  7. Longitudinal data analysis in support of functional stability concepts for leachate management at closed municipal landfills

    Energy Technology Data Exchange (ETDEWEB)

    Gibbons, Robert D., E-mail: rdg@uchicago.edu [Center for Health Statistics, University of Chicago, 5841 S. Maryland Avenue, Chicago, IL 60637 (United States); Morris, Jeremy W.F., E-mail: jmorris@geosyntec.com [Geosyntec Consultants, 10220 Old Columbia Road, Suite A, Columbia, MD 21046 (United States); Prucha, Christopher P., E-mail: cprucha@wm.com [Groundwater Protection Program, Waste Management, 1550 Balmer Road, Box 200, Model City, NY 14107 (United States); Caldwell, Michael D., E-mail: mcaldwell@wm.com [Groundwater Protection Program, Waste Management, 3623 Wilson Road, Humble, TX 77396 (United States); Staley, Bryan F., E-mail: BStaley@erefdn.org [Environmental Research and Education Foundation, 3301 Benson Drive, Suite 301, Raleigh, NC 27609 (United States)

    2014-09-15

    Highlights: • Longitudinal data analysis using a mixed-effects regression model. • Dataset consisted of a total of 1402 samples from 101 closed municipal landfills. • Target analytes and classes generally showed predictable degradation trends. • Validates historical studies focused on macro organic indicators such as BOD. • BOD can serve as “gateway” indicator for planning leachate management. - Abstract: Landfill functional stability provides a target that supports no environmental threat at the relevant point of exposure in the absence of active control systems. With respect to leachate management, this study investigates “gateway” indicators for functional stability in terms of the predictability of leachate characteristics, and thus potential threat to water quality posed by leachate emissions. Historical studies conducted on changes in municipal solid waste (MSW) leachate concentrations over time (longitudinal analysis) have concentrated on indicator compounds, primarily chemical oxygen demand (COD) and biochemical oxygen demand (BOD). However, validation of these studies using an expanded database and larger constituent sets has not been performed. This study evaluated leachate data using a mixed-effects regression model to determine the extent to which leachate constituent degradation can be predicted based on waste age or operational practices. The final dataset analyzed consisted of a total of 1402 samples from 101 MSW landfills. Results from the study indicated that all leachate constituents exhibit a decreasing trend with time in the post-closure period, with 16 of the 25 target analytes and aggregate classes exhibiting a statistically significant trend consistent with well-studied indicators such as BOD. Decreasing trends in BOD concentration after landfill closure can thus be considered representative of trends for many leachate constituents of concern.

  8. Evaluation of ventricular dysfunction using semi-automatic longitudinal strain analysis of four-chamber cine MR imaging.

    Science.gov (United States)

    Kawakubo, Masateru; Nagao, Michinobu; Kumazawa, Seiji; Yamasaki, Yuzo; Chishaki, Akiko S; Nakamura, Yasuhiko; Honda, Hiroshi; Morishita, Junji

    2016-02-01

    The aim of this study was to evaluate ventricular dysfunction using the longitudinal strain analysis in 4-chamber (4CH) cine MR imaging, and to investigate the agreement between the semi-automatic and manual measurements in the analysis. Fifty-two consecutive patients with ischemic, or non-ischemic cardiomyopathy and repaired tetralogy of Fallot who underwent cardiac MR examination incorporating cine MR imaging were retrospectively enrolled. The LV and RV longitudinal strain values were obtained by semi-automatically and manually. Receiver operating characteristic (ROC) analysis was performed to determine the optimal cutoff of the minimum longitudinal strain value for the detection of patients with cardiac dysfunction. The correlations between manual and semi-automatic measurements for LV and RV walls were analyzed by Pearson coefficient analysis. ROC analysis demonstrated the optimal cut-off of the minimum longitudinal strain values (εL_min) for diagnoses the LV and RV dysfunction at a high accuracy (LV εL_min = -7.8 %: area under the curve, 0.89; sensitivity, 83 %; specificity, 91 %, RV εL_min = -15.7 %: area under the curve, 0.82; sensitivity, 92 %; specificity, 68 %). Excellent correlations between manual and semi-automatic measurements for LV and RV free wall were observed (LV, r = 0.97, p cine MR imaging can evaluate LV and RV dysfunction with simply and easy measurements. The strain analysis could have extensive application in cardiac imaging for various clinical cases.

  9. Comprehension of metaphors and idioms in patients with Alzheimer's disease: a longitudinal study.

    Science.gov (United States)

    Papagno, C

    2001-07-01

    Language in patients with Alzheimer's disease has been extensively studied, with the exception of non-literal language comprehension. However, in our speech, we often make use of expressions, which are not necessarily interpreted on a literal ground. Comprehension of metaphors and idioms was examined in 39 patients with probable early Alzheimer's disease. The results showed that the decline of figurative language is not an early symptom of dementia and can occur independently from the impairment of propositional language. It was also found that metaphors and idioms differ as far as the predominant kind of error is concerned.

  10. Rotavirus disease in Guinea-Bissau, West Africa: a review of longitudinal community and hospital studies

    DEFF Research Database (Denmark)

    Fischer, Thea Kølsen; Aaby, Peter; Mølbak, Kåre

    2010-01-01

    Rotavirus is one of the most common causes of childhood diarrheal disease and deaths in sub-Saharan Africa. This article reviews community- and hospital-based surveillance of rotavirus disease in Bissau, Guinea-Bissau, West Africa. Here, rotavirus infections exhibit a seasonal pattern, with annual...... epidemics occurring during the relatively dry and cooler months, from January to April, and few cases registered from May to December. Most children (74%) experience their first infection before the age of 2 years, and rotavirus has been identified as the most pathogenic of all diarrheal agents during 2...

  11. Collaboration in sensor network research: an in-depth longitudinal analysis of assortative mixing patterns.

    Science.gov (United States)

    Pepe, Alberto; Rodriguez, Marko A

    2010-09-01

    Many investigations of scientific collaboration are based on statistical analyses of large networks constructed from bibliographic repositories. These investigations often rely on a wealth of bibliographic data, but very little or no other information about the individuals in the network, and thus, fail to illustrate the broader social and academic landscape in which collaboration takes place. In this article, we perform an in-depth longitudinal analysis of a relatively small network of scientific collaboration (N = 291) constructed from the bibliographic record of a research centerin the development and application of wireless and sensor network technologies. We perform a preliminary analysis of selected structural properties of the network, computing its range, configuration and topology. We then support our preliminary statistical analysis with an in-depth temporal investigation of the assortative mixing of selected node characteristics, unveiling the researchers' propensity to collaborate preferentially with others with a similar academic profile. Our qualitative analysis of mixing patterns offers clues as to the nature of the scientific community being modeled in relation to its organizational, disciplinary, institutional, and international arrangements of collaboration.

  12. An in-depth longitudinal analysis of mixing patterns in a small scientific collaboration network

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Marko A [Los Alamos National Laboratory; Pepe, Alberto [UCLA

    2009-01-01

    Many investigations of scientific collaboration are based on large-scale statistical analyses of networks constructed from bibliographic repositories. These investigations often rely on a wealth of bibliographic data, but very little or no other information about the individuals in the network, and thus, fail to illustate the broader social and academic landscape in which collaboration takes place. In this article, we perform an in-depth longitudinal analysis of a small-scale network of scientific collaboration (N = 291) constructed from the bibliographic record of a research center involved in the development and application of sensor network technologies. We perform a preliminary analysis of selected structural properties of the network, computing its range, configuration and topology. We then support our preliminary statistical analysis with an in-depth temporal investigation of the assortativity mixing of these node characteristics: academic department, affiliation, position, and country of origin of the individuals in the network. Our qualitative analysis of mixing patterns offers clues as to the nature of the scientific community being modeled in relation to its organizational, disciplinary, institutional, and international arrangements of collaboration.

  13. Efficacy of acetylcholinesterase inhibitors versus nootropics in Alzheimer's disease: a retrospective, longitudinal study.

    Science.gov (United States)

    Tsolaki, M; Pantazi, T; Kazis, A

    2001-01-01

    The aim of this study was to investigate the efficacy of nootropics (piracetam, aniracetam, nimodopine and dihydroergicristine) versus acetylcholinesterase inhibitors (AChE-Is) (tacrine and donepezil) in the treatment of Alzheimer's disease. This is a retrospective study of 510 patients with Alzheimer's disease. To determine clinical efficacy of treatment, we used the mean change over time in scores for the following tests: the Mini-Mental State Examination (MMSE); the Cambridge Cognitive Examination for the Elderly; and the Functional Rating Scale for Symptoms of Dementia. In all patients and in patients with severe Alzheimer's disease (baseline MMSE nootropics (-4.38 for AChE-Is group versus 1.48 for nootropics group). For patients with mild dementia (baseline MMSE score between 21 and 26), there was a significantly greater deterioration on the MMSE scale for each time-point in the nootropics group compared with the AChE-Is group. In conclusion, we did not find any strong evidence that a difference in efficacy exists between AChE-Is and nootropics in the treatment of Alzheimer's disease.

  14. Longitudinal non-invasive perilymphatic pressure measurement in patients with Meniere's disease

    NARCIS (Netherlands)

    Rosingh, HJ; Wit, HP; Sulter, AM; Albers, FWJ

    1997-01-01

    The homeostasis of inner-ear fluids is essential for the functions of hearing and equilibrium. Inner-ear disorders, such as Meniere's disease, are affected by inner-ear pressure. The displacement of the human tympanic membrane can be studied by means of the MMS-10 Tympanic Displacement Analyser

  15. Longitudinal association between lifestyle and coronary heart disease risk factors among individuals with spinal cord injury

    NARCIS (Netherlands)

    de Groot, S.; Post, M. W.; Snoek, G. J.; Schuitemaker, M.; van der Woude, L. H.

    Objective: To investigate: (1) the course of coronary heart disease risk factors (lipid profiles and body mass index (BMI)) in the first five years after discharge from inpatient spinal cord injury (SCI) rehabilitation and (2) the association between lifestyle (physical activity, self-care related

  16. Domain or Not Domain? That Is the Question: Longitudinal Semantic Deterioration in Alzheimer's Disease

    Science.gov (United States)

    Moreno-Martinez, F. Javier; Goni-Imizcoz, Miguel; Spitznagel, Mary Beth

    2011-01-01

    Category specific semantic impairment (e.g. living versus nonliving things) has been reported in association with various pathologies, including herpes simplex encephalitis and semantic dementia. However, evidence is inconsistent regarding whether this effect exists in diseases progressively impacting diverse cortical regions, such as Alzheimer's…

  17. A longitudinal study of Stargardt disease: quantitative assessment of fundus autofluorescence, progression, and genotype correlations.

    Science.gov (United States)

    Fujinami, Kaoru; Lois, Noemi; Mukherjee, Rajarshi; McBain, Vikki A; Tsunoda, Kazushige; Tsubota, Kazuo; Stone, Edwin M; Fitzke, Fred W; Bunce, Catey; Moore, Anthony T; Webster, Andrew R; Michaelides, Michel

    2013-12-17

    We characterized subtypes of fundus autofluorescence (AF) and the progression of retinal atrophy, and correlated these findings with genotype in Stargardt disease. Full clinical examination and AF imaging was undertaken in 68 patients with Stargardt disease. The baseline data were compared to those at follow-up. Patients were classified into three AF subtypes: type 1 had a localized low signal at the fovea surrounded by a homogeneous background, type 2 had a localized low signal at the macula surrounded by a heterogeneous background with numerous foci of abnormal signal, and type 3 had multiple low signal areas at the posterior pole with a heterogeneous background. At baseline, there were 19 patients with type 1, 41 with type 2, and 8 with type 3 disease. The areas of reduced AF signal were measured and rate of atrophy enlargement (RAE) was calculated as the difference of the atrophy size over time (mm²) divided by the follow-up interval (years). Molecular screening of ABCA4 was undertaken. The mean follow-up interval was 9.1 years. A total of 42% cases with type 1 disease progressed to type 2, and 12% with type 2 progressed to type 3. The RAE (mm²/y) based upon baseline AF subtypes was significantly different; 0.06 in type 1, 0.67 in type 2, and 4.37 in type 3. ABCA4 variants were identified in 57 patients. There was a significant association between AF subtype and genotype. The AF pattern at baseline influences the enlargement of atrophy over time and has genetic correlates. These data are likely to assist in the provision of counseling on prognosis in Stargardt disease and be valuable for future clinical trials.

  18. Longitudinal follow-up of Zika virus RNA in semen of a traveller returning from Barbados to the Netherlands with Zika virus disease, March 2016

    NARCIS (Netherlands)

    C.B.E.M. Reusken (Chantal); S.D. Pas (Suzan); C.H. Geurts van Kessel (Corine); R. Mögling (Ramona); J.J.A. van Kampen (Jeroen); T. Langerak (Thomas); M.P.G. Koopmans D.V.M. (Marion); A.A. Eijck (Annemiek); E.C.M. van Gorp (Eric)

    2016-01-01

    textabstractWe report the longitudinal follow-up of Zika virus (ZIKV) RNA in semen of a traveller who developed ZIKV disease after return to the Netherlands from Barbados, March 2016. Persistence of ZIKV RNA in blood, urine, saliva and semen was followed until the loads reached undetectable levels.

  19. Risk Factors for Nursing Home Placement in Alzheimer's Disease: A Longitudinal Study of Cognition, ADL, Service Utilization, and Cholinesterase Inhibitor Treatment

    Science.gov (United States)

    Wattmo, Carina; Wallin, Asa K.; Londos, Elisabet; Minthon, Lennart

    2011-01-01

    Purpose of the Study: To identify risk factors for early nursing home placement (NHP) in Alzheimer's disease (AD), focusing on the impact of longitudinal change in cognition, activities of daily living (ADL), service utilization, and cholinesterase inhibitor treatment (ChEI). Design and Methods: In an open, 3-year, prospective, multicenter study…

  20. Longitudinal follow-up of Zika virus RNA in semen of a traveller returning from Barbados to the Netherlands with Zika virus disease, march 2016

    NARCIS (Netherlands)

    C.B.E.M. Reusken (Chantal); S.D. Pas (Suzan); C.H. Geurts van Kessel (Corine); R. Mögling (Ramona); J.J.A. van Kampen (Jeroen); T. Langerak (Thomas); M.P.G. Koopmans D.V.M. (Marion); A.A. Eijck (Annemiek); E.C.M. van Gorp (Eric)

    2016-01-01

    textabstractWe report the longitudinal follow-up of Zika virus (ZIKV) RNA in semen of a traveller who developed ZIKV disease after return to the Netherlands from Barbados, March 2016. Persistence of ZIKV RNA in blood, urine, saliva and semen was followed until the loads reached undetectable levels.

  1. A Longitudinal Study of Transitions Between Informal and Formal Care in Alzheimer Disease Using Multistate Models in the European ICTUS Cohort.

    NARCIS (Netherlands)

    Coley, N.; Gallini, A.; Gares, V.; Gardette, V.; Andrieu, S.; Olde Rikkert, M.G.M.; et al.,

    2015-01-01

    BACKGROUND: We aimed to describe longitudinal patterns of care in community-dwelling European patients with Alzheimer disease (AD), and determine patient-, caregiver-, and country-related predictors of transitions across different care levels. METHODS: Two-year follow-up data from ICTUS cohort (1375

  2. Floquet stability analysis of the longitudinal dynamics of two hovering model insects

    Science.gov (United States)

    Wu, Jiang Hao; Sun, Mao

    2012-01-01

    Because of the periodically varying aerodynamic and inertial forces of the flapping wings, a hovering or constant-speed flying insect is a cyclically forcing system, and, generally, the flight is not in a fixed-point equilibrium, but in a cyclic-motion equilibrium. Current stability theory of insect flight is based on the averaged model and treats the flight as a fixed-point equilibrium. In the present study, we treated the flight as a cyclic-motion equilibrium and used the Floquet theory to analyse the longitudinal stability of insect flight. Two hovering model insects were considered—a dronefly and a hawkmoth. The former had relatively high wingbeat frequency and small wing-mass to body-mass ratio, and hence very small amplitude of body oscillation; while the latter had relatively low wingbeat frequency and large wing-mass to body-mass ratio, and hence relatively large amplitude of body oscillation. For comparison, analysis using the averaged-model theory (fixed-point stability analysis) was also made. Results of both the cyclic-motion stability analysis and the fixed-point stability analysis were tested by numerical simulation using complete equations of motion coupled with the Navier–Stokes equations. The Floquet theory (cyclic-motion stability analysis) agreed well with the simulation for both the model dronefly and the model hawkmoth; but the averaged-model theory gave good results only for the dronefly. Thus, for an insect with relatively large body oscillation at wingbeat frequency, cyclic-motion stability analysis is required, and for their control analysis, the existing well-developed control theories for systems of fixed-point equilibrium are no longer applicable and new methods that take the cyclic variation of the flight dynamics into account are needed. PMID:22491980

  3. A Randomized Longitudinal Factorial Design to Assess Malaria Vector Control and Disease Management Interventions in Rural Tanzania

    Directory of Open Access Journals (Sweden)

    Randall A. Kramer

    2014-05-01

    Full Text Available The optimization of malaria control strategies is complicated by constraints posed by local health systems, infrastructure, limited resources, and the complex interactions between infection, disease, and treatment. The purpose of this paper is to describe the protocol of a randomized factorial study designed to address this research gap. This project will evaluate two malaria control interventions in Mvomero District, Tanzania: (1 a disease management strategy involving early detection and treatment by community health workers using rapid diagnostic technology; and (2 vector control through community-supported larviciding. Six study villages were assigned to each of four groups (control, early detection and treatment, larviciding, and early detection and treatment plus larviciding. The primary endpoint of interest was change in malaria infection prevalence across the intervention groups measured during annual longitudinal cross-sectional surveys. Recurring entomological surveying, household surveying, and focus group discussions will provide additional valuable insights. At baseline, 962 households across all 24 villages participated in a household survey; 2,884 members from 720 of these households participated in subsequent malariometric surveying. The study design will allow us to estimate the effect sizes of different intervention mixtures. Careful documentation of our study protocol may also serve other researchers designing field-based intervention trials.

  4. A randomized longitudinal factorial design to assess malaria vector control and disease management interventions in rural Tanzania.

    Science.gov (United States)

    Kramer, Randall A; Mboera, Leonard E G; Senkoro, Kesheni; Lesser, Adriane; Shayo, Elizabeth H; Paul, Christopher J; Miranda, Marie Lynn

    2014-05-16

    The optimization of malaria control strategies is complicated by constraints posed by local health systems, infrastructure, limited resources, and the complex interactions between infection, disease, and treatment. The purpose of this paper is to describe the protocol of a randomized factorial study designed to address this research gap. This project will evaluate two malaria control interventions in Mvomero District, Tanzania: (1) a disease management strategy involving early detection and treatment by community health workers using rapid diagnostic technology; and (2) vector control through community-supported larviciding. Six study villages were assigned to each of four groups (control, early detection and treatment, larviciding, and early detection and treatment plus larviciding). The primary endpoint of interest was change in malaria infection prevalence across the intervention groups measured during annual longitudinal cross-sectional surveys. Recurring entomological surveying, household surveying, and focus group discussions will provide additional valuable insights. At baseline, 962 households across all 24 villages participated in a household survey; 2,884 members from 720 of these households participated in subsequent malariometric surveying. The study design will allow us to estimate the effect sizes of different intervention mixtures. Careful documentation of our study protocol may also serve other researchers designing field-based intervention trials.

  5. Gray matter concentration and effective connectivity changes in Alzheimer's disease: a longitudinal structural MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xingfeng; Coyle, Damien; Maguire, Liam; Watson, David R.; McGinnity, Thomas M. [University of Ulster, Intelligent Systems Research Centre, Magee Campus, Derry, Northern Ireland (United Kingdom)

    2011-10-15

    Understanding disease progression in Alzheimer's disease (AD) awaits the resolution of three fundamental questions: first, can we identify the location of ''seed'' regions where neuropathology is first present? Some studies have suggested the medial temporal lobe while others have suggested the hippocampus. Second, are there similar atrophy rates within affected regions in AD? Third, is there evidence of causality relationships between different affected regions in AD progression ?To address these questions, we conducted a longitudinal MRI study to investigate the gray matter (GM) changes in AD progression. Abnormal brain regions were localized by a standard voxel-based morphometry method, and the absolute atrophy rate in these regions was calculated using a robust regression method. Primary foci of atrophy were identified in the hippocampus and middle temporal gyrus (MTG). A model based upon the Granger causality approach was developed to investigate the cause-effect relationship over time between these regions based on GM concentration. Results show that in the earlier stages of AD, primary pathological foci are in the hippocampus and entorhinal cortex. Subsequently, atrophy appears to subsume the MTG. The causality results show that there is in fact little difference between AD and age-matched healthy control in terms of hippocampus atrophy, but there are larger differences in MTG, suggesting that local pathology in MTG is the predominant progressive abnormality during intermediate stages of AD development. (orig.)

  6. A longitudinal assessment of changes in bacterial community composition associated with the development of periodontal disease in dogs.

    Science.gov (United States)

    Wallis, Corrin; Marshall, Mark; Colyer, Alison; O'Flynn, Ciaran; Deusch, Oliver; Harris, Stephen

    2015-12-31

    Periodontal disease is the most widespread oral disease in dogs. Whilst the involvement of bacteria in the aetiology of periodontitis is well established the role of individual species and their complex interactions with the host is not well understood. The objective of this research was therefore to perform a longitudinal study in dogs to identify the changes that occur in subgingival bacterial communities during the transition from mild gingivitis to the early stages of periodontitis (dogs every six weeks for up to 60 weeks. The microbial composition of plaque samples was determined using 454-pyrosequencing of the 16S rDNA. A group of aerobic Gram negative species, including Bergeyella zoohelcum COT-186, Moraxella sp. COT-017, Pasteurellaceae sp. COT-080, and Neisseria shayeganii COT-090 decreased in proportion as teeth progressed to mild periodontitis. In contrast, there was less evidence that increases in the proportion of individual species were associated with the onset of periodontitis, although a number of species (particularly members of the Firmicutes) became more abundant as gingivitis severity increased. There were small increases in Shannon diversity, suggesting that plaque community membership remains relatively stable but that bacterial proportions change during progression into periodontitis. This is the first study to demonstrate the temporal dynamics of the canine oral microbiota; it showed that periodontitis results from a microbial succession predominantly characterised by a reduction of previously abundant, health associated taxa. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  7. Cognitive function and advanced kidney disease: longitudinal trends and impact on decision-making

    OpenAIRE

    Iyasere, Osasuyi; Okai, David; Brown, Edwina

    2017-01-01

    Background: Cognitive impairment commonly affects renal patients. But little is known about the influence of dialysis modality on cognitive trends or the influence of cognitive impairment on decision-making in renal patients. This study evaluated cognitive trends amongst chronic kidney disease (CKD), haemodialysis (HD) and peritoneal dialysis (PD) patients. The relationship between cognitive impairment and decision-making capacity (DMC) was also assessed. Methods: Patients were recruited from...

  8. Neuropsychiatric and cardiometabolic comorbidities in patients with previously diagnosed Cushing's disease: a longitudinal observational study

    OpenAIRE

    Dimopoulou, C; Geraedts, V; Stalla, G K; Sievers, C

    2015-01-01

    INTRODUCTION: Only few studies have systematically investigated neuropsychiatric aspects in patients with Cushing's disease (CD). Pain syndromes have been described in patients with pituitary adenomas, but so far no systematical investigation has been conducted in patients with CD. Additionally, CD has an association with cardiometabolic comorbidities which ultimately leads to increased morbidity and mortality. Long-term treatment of the hypercortisolic state cannot prevent the persistence of...

  9. Child health in arid areas of Ethiopia: longitudinal study of the morbidity in infectious diseases.

    Science.gov (United States)

    Lindtjørn, B; Alemu, T; Bjorvatn, B

    1992-01-01

    We describe the incidence of some childhood infections in drought prone areas of southern Ethiopia. Our results are based on 24 months' biweekly observations of 828 children aged 0-5 years in the pastoralist community of Dubluk and the agricultural community of Elka. An average of 23% of the children in Dubluk and 13% in Elka were sick during any 2-week period. Diarrhoeal diseases represented the main cause of morbidity, but the yearly number of diarrhoeal episodes were lower than previously reported from Ethiopia. Respiratory tract infections and to a lesser extent diarrhoeal diseases, showed highest incidence rates during the main dry season. The highest incidence of lower respiratory tract infections coincided with an outbreak of measles. In Dubluk, children who lived near to the wells had higher incidence rates than those who lived further away, probably reflecting the importance of crowding on transmission rates. In Elka, literacy of mothers was associated with reduced incidence of both diarrhoeal and respiratory tract infections, whereas the use of open pit latrines was associated with increased diarrhoeal incidence. The decline in disease incidence in this region during the last months of our study may reflect an improvement of nutritional status.

  10. A genome-wide longitudinal transcriptome analysis of the aging model Podospora anserina.

    Science.gov (United States)

    Philipp, Oliver; Hamann, Andrea; Servos, Jörg; Werner, Alexandra; Koch, Ina; Osiewacz, Heinz D

    2013-01-01

    Aging of biological systems is controlled by various processes which have a potential impact on gene expression. Here we report a genome-wide transcriptome analysis of the fungal aging model Podospora anserina. Total RNA of three individuals of defined age were pooled and analyzed by SuperSAGE (serial analysis of gene expression). A bioinformatics analysis identified different molecular pathways to be affected during aging. While the abundance of transcripts linked to ribosomes and to the proteasome quality control system were found to decrease during aging, those associated with autophagy increase, suggesting that autophagy may act as a compensatory quality control pathway. Transcript profiles associated with the energy metabolism including mitochondrial functions were identified to fluctuate during aging. Comparison of wild-type transcripts, which are continuously down-regulated during aging, with those down-regulated in the long-lived, copper-uptake mutant grisea, validated the relevance of age-related changes in cellular copper metabolism. Overall, we (i) present a unique age-related data set of a longitudinal study of the experimental aging model P. anserina which represents a reference resource for future investigations in a variety of organisms, (ii) suggest autophagy to be a key quality control pathway that becomes active once other pathways fail, and (iii) present testable predictions for subsequent experimental investigations.

  11. A genome-wide longitudinal transcriptome analysis of the aging model Podospora anserina.

    Directory of Open Access Journals (Sweden)

    Oliver Philipp

    Full Text Available Aging of biological systems is controlled by various processes which have a potential impact on gene expression. Here we report a genome-wide transcriptome analysis of the fungal aging model Podospora anserina. Total RNA of three individuals of defined age were pooled and analyzed by SuperSAGE (serial analysis of gene expression. A bioinformatics analysis identified different molecular pathways to be affected during aging. While the abundance of transcripts linked to ribosomes and to the proteasome quality control system were found to decrease during aging, those associated with autophagy increase, suggesting that autophagy may act as a compensatory quality control pathway. Transcript profiles associated with the energy metabolism including mitochondrial functions were identified to fluctuate during aging. Comparison of wild-type transcripts, which are continuously down-regulated during aging, with those down-regulated in the long-lived, copper-uptake mutant grisea, validated the relevance of age-related changes in cellular copper metabolism. Overall, we (i present a unique age-related data set of a longitudinal study of the experimental aging model P. anserina which represents a reference resource for future investigations in a variety of organisms, (ii suggest autophagy to be a key quality control pathway that becomes active once other pathways fail, and (iii present testable predictions for subsequent experimental investigations.

  12. Diagnosing the EAP needs of Turkish medical students: A longitudinal critical needs analysis

    Directory of Open Access Journals (Sweden)

    Neslihan Önder Özdemir

    2014-10-01

    Full Text Available This study uses a longitudinal critical needs analysis to diagnose the English for academic purposes (EAP needs of Turkish medical students seeking proficiency in medical English and contribute to needs analysis methodology. The data were collected from medical students and specialists. To obtain valid and reliable information about medical students’ needs, three types of instruments were used: ethnographic methods, including sustained observation and participation in a research setting; reflective journals; and a questionnaire and in-depth interview. The questionnaire design was based on essays collected from the students during their study, and the items were constructed from the students’ own words. To the best of my knowledge, this study is the first attempt in the literature to triangulate both methods and data with a focus on critical pedagogy to diagnose EAP needs. The findings are the result of the triangulation of data and methodology to ensure the reliability and validity of the findings. A total of 525 subjects participated in the research (186 participants in the pilot study and 339 participants in the main study. The findings revealed medical students’ expectations of their English for specific purposes (ESP instructor, students’ shortcomings, and the problems and strategies they use while learning medical English. The interview data analysis sought to determine whether higher education students can be a reliable source to consult for their own educational needs in higher education. The methodology followed here can be replicated in other mainstream classrooms.

  13. Time-Course Gene Set Analysis for Longitudinal Gene Expression Data.

    Directory of Open Access Journals (Sweden)

    Boris P Hejblum

    2015-06-01

    Full Text Available Gene set analysis methods, which consider predefined groups of genes in the analysis of genomic data, have been successfully applied for analyzing gene expression data in cross-sectional studies. The time-course gene set analysis (TcGSA introduced here is an extension of gene set analysis to longitudinal data. The proposed method relies on random effects modeling with maximum likelihood estimates. It allows to use all available repeated measurements while dealing with unbalanced data due to missing at random (MAR measurements. TcGSA is a hypothesis driven method that identifies a priori defined gene sets with significant expression variations over time, taking into account the potential heterogeneity of expression within gene sets. When biological conditions are compared, the method indicates if the time patterns of gene sets significantly differ according to these conditions. The interest of the method is illustrated by its application to two real life datasets: an HIV therapeutic vaccine trial (DALIA-1 trial, and data from a recent study on influenza and pneumococcal vaccines. In the DALIA-1 trial TcGSA revealed a significant change in gene expression over time within 69 gene sets during vaccination, while a standard univariate individual gene analysis corrected for multiple testing as well as a standard a Gene Set Enrichment Analysis (GSEA for time series both failed to detect any significant pattern change over time. When applied to the second illustrative data set, TcGSA allowed the identification of 4 gene sets finally found to be linked with the influenza vaccine too although they were found to be associated to the pneumococcal vaccine only in previous analyses. In our simulation study TcGSA exhibits good statistical properties, and an increased power compared to other approaches for analyzing time-course expression patterns of gene sets. The method is made available for the community through an R package.

  14. The impact of removing financial incentives from clinical quality indicators: longitudinal analysis of four Kaiser Permanente indicators.

    NARCIS (Netherlands)

    Lester, H.; Schmittdiel, J.; Selby, J.; Fireman, B.; Campbell, S.M.; Lee, J.; Whippy, A.; Madvig, P.

    2010-01-01

    OBJECTIVE: To evaluate the effect of financial incentives on four clinical quality indicators common to pay for performance plans in the United Kingdom and at Kaiser Permanente in California. DESIGN: Longitudinal analysis. SETTING: 35 medical facilities of Kaiser Permanente Northern California,

  15. An analysis of the effects of aeroelasticity on static longitudinal stability and control of a swept-back-wing airplane

    Science.gov (United States)

    Skoog, Richard B

    1951-01-01

    A theoretical analysis of the effects of aeroelasticity on the stick-fixed static longitudinal stability and elevator angle required for balance of an airplane is presented together with calculated effects for a swept-wing bomber of relatively high flexibility. Although large changes in stability due to certain parameters are indicated for the example airplane, the over-all stability change after considering all parameters was quite small, compared to the individual effects, due to the counterbalancing of wing and tail contributions. The effect of flexibility on longitudinal control for the example airplane was found to be of little real importance.

  16. A retrospective analysis of longitudinal changes in bone mineral content in cystic fibrosis.

    Science.gov (United States)

    Chirita-Emandi, Adela; Shepherd, Sheila; Kyriakou, Andreas; McNeilly, Jane D; Dryden, Carol; Corrigan, Donna; Devenny, Anne; Ahmed, Syed Faisal

    2017-08-28

    We aimed to describe the longitudinal changes in bone mineral content and influencing factors, in children with cystic fibrosis (CF). One hundred children (50 females) had dual X-ray absorptiometry (DXA) performed. Of these, 48 and 24 children had two to three scans, respectively over 10 years of follow-up. DXA data were expressed as lumbar spine bone mineral content standard deviation score (LSBMCSDS) adjusted for age, gender, ethnicity and bone area. Markers of disease, anthropometry and bone biochemistry were collected retrospectively. Baseline LSBMCSDS was >0.5 SDS in 13% children, between -0.5; 0.5 SDS, in 50% and ≤-0.5 in the remainder. Seventy-eight percent of the children who had baseline LSBMCSDS >-0.5, and 35% of the children with poor baseline (LSBMCSDS0.5), showed decreasing values in subsequent assessments. However, mean LS BMC SDS did not show a significant decline in subsequent assessments (-0.51; -0.64; -0.56; p=0.178). Lower forced expiratory volume in 1 s percent (FEV1%) low body mass index standard deviation scores (BMI SDS) and vitamin D were associated with reduction in BMC. Bone mineral content as assessed by DXA is sub-optimal and decreases with time in most children with CF and this study has highlighted parameters that can be addressed to improve bone health.

  17. Colorimetric and longitudinal analysis of leukocoria in recreational photographs of children with retinoblastoma.

    Directory of Open Access Journals (Sweden)

    Alireza Abdolvahabi

    Full Text Available Retinoblastoma is the most common primary intraocular tumor in children. The first sign that is often reported by parents is the appearance of recurrent leukocoria (i.e., "white eye" in recreational photographs. A quantitative definition or scale of leukocoria--as it appears during recreational photography--has not been established, and the amount of clinical information contained in a leukocoric image (collected by a parent remains unknown. Moreover, the hypothesis that photographic leukocoria can be a sign of early stage retinoblastoma has not been tested for even a single patient. This study used commercially available software (Adobe Photoshop® and standard color space conversion algorithms (operable in Microsoft Excel® to quantify leukocoria in actual "baby pictures" of 9 children with retinoblastoma (that were collected by parents during recreational activities i.e., in nonclinical settings. One particular patient with bilateral retinoblastoma ("Patient Zero" was photographed >7, 000 times by his parents (who are authors of this study over three years: from birth, through diagnosis, treatment, and remission. This large set of photographs allowed us to determine the longitudinal and lateral frequency of leukocoria throughout the patient's life. This study establishes: (i that leukocoria can emerge at a low frequency in early-stage retinoblastoma and increase in frequency during disease progression, but decrease upon disease regression, (ii that Hue, Saturation and Value (i.e., HSV color space are suitable metrics for quantifying the intensity of retinoblastoma-linked leukocoria; (iii that different sets of intraocular retinoblastoma tumors can produce distinct leukocoric reflections; and (iv the Saturation-Value plane of HSV color space represents a convenient scale for quantifying and classifying pupillary reflections as they appear during recreational photography.

  18. Training, Innovation and Business Performance: An Analysis of the Business Longitudinal Survey.

    Science.gov (United States)

    Dockery, A. Michael

    This paper uses the Australian Bureau of Statistics' Business Longitudinal Survey to explore relationships between training, innovation, and firm performance for Australian businesses with less than 200 employees. The longitudinal nature of the data is used to test various hypotheses about the nature of the link between training, business changes,…

  19. Longitudinal Analysis of Personal and Work-Related Factors Associated With Turnover Among Nurses

    NARCIS (Netherlands)

    Estryn-Behar, Madeleine; van der Heijden, Beatrice; Fry, Clementine; Hasselhorn, Hans Martin

    2010-01-01

    AB Background: Although many scholars have acknowledged the relationship between personal and work-related factors associated with job search and actual turnover, there is a lack of longitudinal designs that test this relationship empirically. Objectives: This longitudinal study examines specific

  20. Post-traumatic Stress Disorder and Risk of Parkinson Disease: A Nationwide Longitudinal Study.

    Science.gov (United States)

    Chan, Yee-Lam E; Bai, Ya-Mei; Hsu, Ju-Wei; Huang, Kai-Lin; Su, Tung-Ping; Li, Cheng-Ta; Lin, Wei-Chen; Pan, Tai-Long; Chen, Tzeng-Ji; Tsai, Shih-Jen; Chen, Mu-Hong

    2017-08-01

    Increasing evidence has suggested a relationship between post-traumatic stress disorder (PTSD) and neurodegenerative disorder, such as Alzheimer disease. The association between PTSD and Parkinson disease (PD), however, remains unclear. Using the Taiwan National Health Insurance Research Database, 7,280 subjects (1,456 patients aged ≥45 years with PTSD and 5,824 age-/sex-matched individuals without PTSD) were enrolled between 2002 and 2009 and followed to the end of 2011. Subjects who developed PD during the follow-up period were identified. An increased risk of developing PD was found in patients with PTSD (Wald χ 2  = 12.061, hazard ratio [HR]: 3.46, 95% confidence interval [CI]: 1.72-6.96) compared with individuals without PTSD, after adjusting for demographic data and medical and psychiatric comorbidities. The sensitivity tests after excluding the first year observation (Wald χ 2  = 7.948, HR: 3.01, 95% CI: 1.40-6.46) and the first 3-year observation (Wald χ 2  = 5.099, HR: 3.07, 95% CI: 1.16-8.15) were consistent. Patients with PTSD had an elevated risk of developing PD in later life. Further studies would be required to clarify the exact pathophysiology between PTSD and PD and to investigate whether the prompt intervention for PTSD may reduce this risk. Copyright © 2017 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

  1. Alterations of the Subgingival Microbiota in Pediatric Crohn's Disease Studied Longitudinally in Discovery and Validation Cohorts.

    Science.gov (United States)

    Kelsen, Judith; Bittinger, Kyle; Pauly-Hubbard, Helen; Posivak, Leah; Grunberg, Stephanie; Baldassano, Robert; Lewis, James D; Wu, Gary D; Bushman, Frederic D

    2015-12-01

    Oral manifestations are common in Crohn's disease (CD). Here we characterized the subgingival microbiota in pediatric patients with CD initiating therapy and after 8 weeks to identify microbial community features associated with CD and therapy. Pediatric patients with CD were recruited from The Children's Hospital of Pennsylvania. Healthy control subjects were recruited from primary care or orthopedics clinic. Subgingival plaque samples were collected at initiation of therapy and after 8 weeks. Treatment exposures included 5-ASAs, immunomodulators, steroids, and infliximab. The microbiota was characterized by 16S rRNA gene sequencing. The study was repeated in separate discovery (35 CD, 43 healthy) and validation cohorts (43 CD, 31 healthy). Most subjects in both cohorts demonstrated clinical response after 8 weeks of therapy (discovery cohort 88%, validation cohort 79%). At week 0, both antibiotic exposure and disease state were associated with differences in bacterial community composition. Seventeen genera were identified in the discovery cohort as candidate biomarkers, of which 11 were confirmed in the validation cohort. Capnocytophaga, Rothia, and TM7 were more abundant in CD relative to healthy controls. Other bacteria were reduced in abundance with antibiotic exposure among CD subjects. CD-associated genera were not enriched compared with healthy controls after 8 weeks of therapy. Subgingival microbial community structure differed with CD and antibiotic use. Results in the discovery cohort were replicated in a separate validation cohort. Several potentially pathogenic bacterial lineages were associated with CD but were not diminished in abundance by antibiotic treatment, suggesting targets for additional surveillance.

  2. Predictive Biomarkers of Gastroesophageal Reflux Disease and Barrett's Esophagus in World Trade Center Exposed Firefighters: a 15 Year Longitudinal Study.

    Science.gov (United States)

    Haider, Syed H; Kwon, Sophia; Lam, Rachel; Lee, Audrey K; Caraher, Erin J; Crowley, George; Zhang, Liqun; Schwartz, Theresa M; Zeig-Owens, Rachel; Liu, Mengling; Prezant, David J; Nolan, Anna

    2018-02-15

    Gastroesophageal reflux disease (GERD) and Barrett's Esophagus (BE), which are prevalent in the World Trade Center (WTC) exposed and general populations, negatively impact quality of life and cost of healthcare. GERD, a risk factor of BE, is linked to obstructive airways disease (OAD). We aim to identify serum biomarkers of GERD/BE, and assess the respiratory and clinical phenotype of a longitudinal cohort of never-smoking, male, WTC-exposed rescue workers presenting with pulmonary symptoms. Biomarkers collected soon after WTC-exposure were evaluated in optimized predictive models of GERD/BE. In the WTC-exposed cohort, the prevalence of BE is at least 6 times higher than in the general population. GERD/BE cases had similar lung function, D LCO , bronchodilator response and long-acting β-agonist use compared to controls. In confounder-adjusted regression models, TNF-α ≥ 6 pg/mL predicted both GERD and BE. GERD was also predicted by C-peptide ≥ 360 pg/mL, while BE was predicted by fractalkine ≥ 250 pg/mL and IP-10 ≥ 290 pg/mL. Finally, participants with GERD had significantly increased use of short-acting β-agonist compared to controls. Overall, biomarkers sampled prior to GERD/BE presentation showed strong predictive abilities of disease development. This study frames future investigations to further our understanding of aerodigestive pathology due to particulate matter exposure.

  3. Mendelian randomization analysis of a time-varying exposure for binary disease outcomes using functional data analysis methods.

    Science.gov (United States)

    Cao, Ying; Rajan, Suja S; Wei, Peng

    2016-12-01

    A Mendelian randomization (MR) analysis is performed to analyze the causal effect of an exposure variable on a disease outcome in observational studies, by using genetic variants that affect the disease outcome only through the exposure variable. This method has recently gained popularity among epidemiologists given the success of genetic association studies. Many exposure variables of interest in epidemiological studies are time varying, for example, body mass index (BMI). Although longitudinal data have been collected in many cohort studies, current MR studies only use one measurement of a time-varying exposure variable, which cannot adequately capture the long-term time-varying information. We propose using the functional principal component analysis method to recover the underlying individual trajectory of the time-varying exposure from the sparsely and irregularly observed longitudinal data, and then conduct MR analysis using the recovered curves. We further propose two MR analysis methods. The first assumes a cumulative effect of the time-varying exposure variable on the disease risk, while the second assumes a time-varying genetic effect and employs functional regression models. We focus on statistical testing for a causal effect. Our simulation studies mimicking the real data show that the proposed functional data analysis based methods incorporating longitudinal data have substantial power gains compared to standard MR analysis using only one measurement. We used the Framingham Heart Study data to demonstrate the promising performance of the new methods as well as inconsistent results produced by the standard MR analysis that relies on a single measurement of the exposure at some arbitrary time point. © 2016 WILEY PERIODICALS, INC.

  4. Optimization and Analysis of a U-Shaped Linear Piezoelectric Ultrasonic Motor Using Longitudinal Transducers.

    Science.gov (United States)

    Yu, Hongpeng; Quan, Qiquan; Tian, Xinqi; Li, He

    2018-03-07

    A novel U-shaped piezoelectric ultrasonic motor that mainly focused on miniaturization and high power density was proposed, fabricated, and tested in this work. The longitudinal vibrations of the transducers were excited to form the elliptical movements on the driving feet. Finite element method (FEM) was used for design and analysis. The resonance frequencies of the selected vibration modes were tuned to be very close to each other with modal analysis and the movement trajectories of the driving feet were gained with transient simulation. The vibration modes and the mechanical output abilities were tested to evaluate the proposed motor further by a prototype. The maximum output speed was tested to be 416 mm/s, the maximum thrust force was 21 N, and the maximum output power was 5.453 W under frequency of 29.52 kHz and voltage of 100 V rms . The maximum output power density of the prototype reached 7.59 W/kg, which was even greater than a previous similar motor under the exciting voltage of 200 V rms . The proposed motor showed great potential for linear driving of large thrust force and high power density.

  5. Vocal fold immobility: a longitudinal analysis of etiology over 20 years.

    Science.gov (United States)

    Rosenthal, Laura H Swibel; Benninger, Michael S; Deeb, Robert H

    2007-10-01

    To determine the current etiology of vocal fold immobility, identify changing trends over the last 20 years, and compare results to historical reports. The present study is a retrospective analysis of all patients seen within a tertiary care institution between 1996 and 2005 with vocal fold immobility. The results were combined with a previous study of patients within the same institution from 1985 through 1995. Results were compared to the literature. The medical records of all patients assigned a primary or additional diagnostic code for vocal cord paralysis were obtained from the electronic database. Eight hundred twenty-seven patients were available for analysis (435 from the most recent cohort), which is substantially larger than any reported series to date. Vocal fold immobility was most commonly associated with a surgical procedure (37%). Nonthyroid surgeries (66%), such as anterior cervical approaches to the spine and carotid endarterectomies, have surpassed thyroid surgery (33%) as the most common iatrogenic causes. These data represent a change from historical figures in which extralaryngeal malignancies were considered the major cause of unilateral immobility. Thyroidectomy continues to cause the majority (80%) of iatrogenic bilateral vocal fold immobility and 30% of all bilateral immobility. This 20-year longitudinal assessment revealed that the etiology of unilateral vocal fold immobility has changed such that there has been a shift from extralaryngeal malignancies to nonthyroid surgical procedures as the major cause. Thyroid surgery remains the most common cause of bilateral vocal fold immobility.

  6. The Walking Renaissance: A Longitudinal Analysis of Walking Travel in the Greater Los Angeles Area, USA

    Directory of Open Access Journals (Sweden)

    Kenneth Joh

    2015-07-01

    Full Text Available Promoting walking travel is considered important for reducing automobile use and improving public health. Recent U.S. transportation policy has incentivized investments in alternative, more sustainable transportation modes such as walking, bicycling and transit in auto-oriented cities such as Los Angeles. Although many past studies have analyzed changes in walking travel across the U.S., there is little clarity on the drivers of change. We address this gap by conducting a longitudinal analysis of walking travel in the greater Los Angeles area from 2001 to 2009. We use travel diary and household data from regional and national surveys to analyze changes in walking trip shares and rates across our study area. Results show that walking has significantly increased across most of Los Angeles, and that increases in walking trips generally correspond with increases in population, employment, and transit service densities. Estimates from fixed-effects regression analysis generally suggest a positive association between population density and walking, and that higher increases in transit stop density are correlated with increased walking trips to and from transit stops. These findings illustrate how regional planning efforts to pursue a coordinated land use-transit planning strategy can help promote walking in auto-oriented or vehicle adopting cities.

  7. Analysis of Exhaled Breath for Disease Detection

    Science.gov (United States)

    Amann, Anton; Miekisch, Wolfram; Schubert, Jochen; Buszewski, Bogusław; Ligor, Tomasz; Jezierski, Tadeusz; Pleil, Joachim; Risby, Terence

    2014-06-01

    Breath analysis is a young field of research with great clinical potential. As a result of this interest, researchers have developed new analytical techniques that permit real-time analysis of exhaled breath with breath-to-breath resolution in addition to the conventional central laboratory methods using gas chromatography-mass spectrometry. Breath tests are based on endogenously produced volatiles, metabolites of ingested precursors, metabolites produced by bacteria in the gut or the airways, or volatiles appearing after environmental exposure. The composition of exhaled breath may contain valuable information for patients presenting with asthma, renal and liver diseases, lung cancer, chronic obstructive pulmonary disease, inflammatory lung disease, or metabolic disorders. In addition, oxidative stress status may be monitored via volatile products of lipid peroxidation. Measurement of enzyme activity provides phenotypic information important in personalized medicine, whereas breath measurements provide insight into perturbations of the human exposome and can be interpreted as preclinical signals of adverse outcome pathways.

  8. Automated cross-sectional and longitudinal hippocampal volume measurement in mild cognitive impairment and Alzheimer's disease.

    Science.gov (United States)

    Leung, Kelvin K; Barnes, Josephine; Ridgway, Gerard R; Bartlett, Jonathan W; Clarkson, Matthew J; Macdonald, Kate; Schuff, Norbert; Fox, Nick C; Ourselin, Sebastien

    2010-07-15

    Volume and change in volume of the hippocampus are both important markers of Alzheimer's disease (AD). Delineation of the structure on MRI is time-consuming and therefore reliable automated methods are required. We describe an improvement (multiple-atlas propagation and segmentation (MAPS)) to our template library-based segmentation technique. The improved technique uses non-linear registration of the best-matched templates from our manually segmented library to generate multiple segmentations and combines them using the simultaneous truth and performance level estimation (STAPLE) algorithm. Change in volume over 12months (MAPS-HBSI) was measured by applying the boundary shift integral using MAPS regions. Methods were developed and validated against manual measures using subsets from Alzheimer's Disease Neuroimaging Initiative (ADNI). The best method was applied to 682 ADNI subjects, at baseline and 12-month follow-up, enabling assessment of volumes and atrophy rates in control, mild cognitive impairment (MCI) and AD groups, and within MCI subgroups classified by subsequent clinical outcome. We compared our measures with those generated by Surgical Navigation Technologies (SNT) available from ADNI. The accuracy of our volumes was one of the highest reported (mean(SD) Jaccard Index 0.80(0.04) (N=30)). Both MAPS baseline volume and MAPS-HBSI atrophy rate distinguished between control, MCI and AD groups. Comparing MCI subgroups (reverters, stable and converters): volumes were lower and rates higher in converters compared with stable and reverter groups (pmethods give accurate and reliable volumes and atrophy rates across the clinical spectrum from healthy aging to AD. Copyright 2010 Elsevier Inc. All rights reserved.

  9. A longitudinal study on clinical diseases and disorders of cattle and goats in Sylhet, Bangladesh

    Directory of Open Access Journals (Sweden)

    Nasrin Sultana Lucky

    2016-03-01

    Full Text Available Objective: The objective of this research work was to find out the prevalence of clinically occurring diseases and the disorders in cattle and goats at the Sylhet Agricultural University area, Sylhet during January to December 2013. Materials and methods: This clinical study was carried out on 775 clinical cases (553 cattle and 222 goats based on the general, clinical, physical and microscopical examination along with common laboratory techniques. Results: The clinically observed cases in cattle were (i gyneco-obstetrical (15.37%; n=85/553; P=0.038, (ii metabolic and nutritional (9.94%; n=55/553; P=0.245, (iii bacterial and viral (26.22%; n=145/553; P=<0.001, (iv parasitic (26.58%; n=147/553; P=<0.001, and (v digestive diseases (21.88%; n=121/553; P=0.008. Similarly, in goats, the prevalences were found to be 14.41 (n=32/222; P=0.041, 15.76 (n=35/222; P=0.078, 30.63 (n=68/222; P=0.001, 23.87 (n=53/222; P=0.020, and 15.31% (n=34/222; P=0.069, respectively. Conclusion: This research work is a groundwork which may facilitate the potential researchers to investigate the details possessions for extensive therapeutic exercises in Bangladesh particularly in Sylhet region for designing the control strategies and conducting the treatment of infection and disorders in cattle and goats. [J Adv Vet Anim Res 2016; 3(1.000: 24-37

  10. Monitoring the newly qualified nurses in Sweden: the Longitudinal Analysis of Nursing Education (LANE study

    Directory of Open Access Journals (Sweden)

    Wallin Lars

    2010-04-01

    Full Text Available Abstract Background The Longitudinal Analysis of Nursing Education (LANE study was initiated in 2002, with the aim of longitudinally examining a wide variety of individual and work-related variables related to psychological and physical health, as well as rates of employee and occupational turnover, and professional development among nursing students in the process of becoming registered nurses and entering working life. The aim of this paper is to present the LANE study, to estimate representativeness and analyse response rates over time, and also to describe common career pathways and life transitions during the first years of working life. Methods Three Swedish national cohorts of nursing students on university degree programmes were recruited to constitute the cohorts. Of 6138 students who were eligible for participation, a total of 4316 consented to participate and responded at baseline (response rate 70%. The cohorts will be followed prospectively for at least three years of their working life. Results Sociodemographic data in the cohorts were found to be close to population data, as point estimates only differed by 0-3% from population values. Response rates were found to decline somewhat across time, and this decrease was present in all analysed subgroups. During the first year after graduation, nearly all participants had qualified as nurses and had later also held nursing positions. The most common reason for not working was due to maternity leave. About 10% of the cohorts who graduated in 2002 and 2004 intended to leave the profession one year after graduating, and among those who graduated in 2006 the figure was almost twice as high. Intention to leave the profession was more common among young nurses. In the cohort who graduated in 2002, nearly every fifth registered nurse continued to further higher educational training within the health professions. Moreover, in this cohort, about 2% of the participants had left the nursing

  11. Longitudinal analysis of meta-analysis literatures in the database of ISI Web of Science.

    Science.gov (United States)

    Zhu, Changtai; Jiang, Ting; Cao, Hao; Sun, Wenguang; Chen, Zhong; Liu, Jinming

    2015-01-01

    The meta-analysis is regarded as an important evidence for making scientific decision. The database of ISI Web of Science collected a great number of high quality literatures including meta-analysis literatures. However, it is significant to understand the general characteristics of meta-analysis literatures to outline the perspective of meta-analysis. In this present study, we summarized and clarified some features on these literatures in the database of ISI Web of Science. We retrieved the meta-analysis literatures in the database of ISI Web of Science including SCI-E, SSCI, A&HCI, CPCI-S, CPCI-SSH, CCR-E, and IC. The annual growth rate, literature category, language, funding, index citation, agencies and countries/territories of the meta-analysis literatures were analyzed, respectively. A total of 95,719 records, which account for 0.38% (99% CI: 0.38%-0.39%) of all literatures, were found in the database. From 1997 to 2012, the annual growth rate of meta-analysis literatures was 18.18%. The literatures involved in many categories, languages, fundings, citations, publication agencies, and countries/territories. Interestingly, the index citation frequencies of the meta-analysis were significantly higher than that of other type literatures such as multi-centre study, randomize controlled trial, cohort study, case control study, and cases report (Panalysis has been becoming more and more prominent in recent years. In future, in order to promote the validity of meta-analysis, the CONSORT and PRISMA standard should be continuously popularized in the field of evidence-based medicine.

  12. Longitudinal evaluation of the prevalence of overweight/obesity in children with congenital heart disease.

    Science.gov (United States)

    Tamayo, Catalina; Manlhiot, Cedric; Patterson, Katie; Lalani, Sheliza; McCrindle, Brian W

    2015-02-01

    Regarding long-term cardiovascular health, obesity may have greater implications for children with congenital heart disease (CHD). We sought to determine trends in anthropometry over time and its association with exercise capacity. Medical records of pediatric patients with CHD were randomly sampled. Serial measurements of weight and height were abstracted, body mass index (BMI) was calculated, and measurements were converted to percentiles and z scores. Analyses of trends were performed using regression models adjusted for repeated measures. Median follow-up after diagnosis for 725 patients was 7.1 years (interquartile range, 1.9-12.8 years). The median initial weight z score was -1.1 (fifth/95th percentile, -3.6/+1.1) and increased over time (+0.103 [0.007] standard deviations [SD]/y; P 2 years old; at that age, the median BMI z score was -0.2 (fifth/95th percentile, -2.6/+1.9) and increased over time (+0.042 [0.007] SD/y; P obesity, 28% of patients had at least 1 BMI measurement indicating overweight and 17% indicating obesity. Available exercise test results (n = 153) showed that overweight/obese patients had lower percent predicted maximum oxygen consumption (-16 [2]%; P obesity over time that may increase their cardiovascular risk and impair their exercise capacity. Copyright © 2015 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  13. Longitudinal PET evaluation of cerebral glucose metabolism in rivastigmine treated patients with mild Alzheimer's disease

    International Nuclear Information System (INIS)

    Stefanova, E.; Forsberg, A.; Wall, A.; Nilsson, A.; Langstroem, B.; Almkvist, O.; Nordberg, A.

    2006-01-01

    In this study 11 patients with mild Alzheimer's disease (AD) were treated with the cholinesterase inhibitor rivastigmine (mean dose 8.6 ± 1.3 mg) for 12 months and underwent positron emission tomography (PET) studies of cerebral glucose metabolism (CMRglc) and neuropsychological testing at baseline and after 12 months. An untreated group of 10 AD patients served as control group. While the untreated AD patients showed a significant decline of CMRglc in the temporo-parietal and frontal cortical regions after 12 months follow-up the rivastigmine-treated patients showed no decline in CMRglc in corresponding cortical brain regions. Furthermore, a significant dose-related increase in CMRglc was recorded in the right frontal association region after 12 months rivastigmine treatment. A positive correlation was observed between changes in CMRglc and several cognitive tests in patients receiving higher doses (10.5-12 mg) of rivastigmine. These results suggest a stabilization effect of rivastigmine on CMRglc in mild AD patients receiving long-term rivastigmine treatment. (author)

  14. The effect of education on rCBF changes in Alzheimer's disease: a longitudinal SPECT study

    International Nuclear Information System (INIS)

    Hanyu, Haruo; Sato, Tomohiko; Shimizu, Soichiro; Kanetaka, Hidekazu; Iwamoto, Toshihiko; Koizumi, Kiyoshi

    2008-01-01

    To determine the relationship of differing levels of education on regional cerebral blood flow (rCBF) in patients with Alzheimer's disease (AD). Fifty-three patients with AD followed-up for an average of 36 months were divided into the high-educated group (HE, ≥12 years of schooling) and low-educated group (LE, 123 I]-iodoamphetamine and the SPECT data were analyzed by 3D-stereotactic surface projections. At initial evaluation, the HE group had greater rCBF deficits in the parietotemporal regions than did the LE group, even though both groups had comparable MMSE and FAST scores. When compared with initial SPECT, follow-up SPECT showed a significant rCBF reduction in widespread regions, including the frontal, parietal, temporal, and limbic lobes of the HE group, while it a significant rCBF reduction in scattered and small regions of the parietotemporal, cingulate, and occipital areas of the LE group, as the HE group had faster cognitive and functional decline than the LE group. The HE group showed lower rCBF at initial SPECT than the LE group, suggesting more advanced AD pathology. As a result, the HE group demonstrated a more extensive and severe reduction of rCBF on follow-up SPECT in association with faster cognitive and functional decline than the LE group. Our SPECT study provides stronger support for the cognitive reserve effects of education in AD. (orig.)

  15. Longitudinal study of self-imposed driving restrictions and deficit awareness in patients with Alzheimer disease.

    Science.gov (United States)

    Cotrell, V; Wild, K

    1999-01-01

    Thirty-five patients with Alzheimer disease (AD), including 19 who were still driving, were evaluated for level of awareness and driving status. There was no significant correlation between driving status and Mini-Mental State Examination (MMSE) scores. Only the attention subscore of the awareness questionnaire yielded a statistically significant difference between drivers and nondrivers. Follow-up of the patients who were still driving was conducted 12-18 months later. All but 4 patients had stopped driving. Caregivers responded to a questionnaire assessing the patient's driving behaviors since the onset of AD. There was no correlation between MMSE and driving status. In 7 of 10 cases, caregivers or patients made the decision that the patient should stop driving. However, caregivers reported long periods between the caregiver's perception that the patient should stop driving and actual cessation (0.5-48 months). Results suggest that AD patients do restrict several areas of their driving voluntarily and that a failure to do so may be associated with an awareness deficit. In particular, a deficit of awareness for attention was significantly associated with an absence of restricted driving behaviors such as avoiding unfamiliar routes. Awareness of a deficit that is related to driving performance may be critical to restricted driving behavior, and this change in behavior may enable the patient to prolong his or her status as a driver.

  16. Filaggrin gene variants and atopic diseases in early childhood assessed longitudinally from birth

    DEFF Research Database (Denmark)

    Bønnelykke, Klaus; Pipper, Christian Bressen; Tavendale, Roger

    2010-01-01

    Copenhagen Prospective Study on Asthma in Childhood (COPSAC) was one of the discovery cohorts of the association between eczema and variants in the filaggrin coding gene (FLG). Here, we study the FLG-associated risk of asthma symptoms in early life and describe the temporal relationship in the de......Copenhagen Prospective Study on Asthma in Childhood (COPSAC) was one of the discovery cohorts of the association between eczema and variants in the filaggrin coding gene (FLG). Here, we study the FLG-associated risk of asthma symptoms in early life and describe the temporal relationship...... diagnosed prospectively by the investigators. FLG variants R501X and Del4 were determined in 382 Caucasians. Filaggrin variants increased risk of developing recurrent wheeze, asthma and asthma exacerbations (hazard ratio 1.82 [1.06-3.12], p = 0.03), which was expressed within the first 1.5 yr of life...... fully in the first year of life (point prevalence ratio for age 0-5 was 1.75 [1.29-2.37]; p-value = 0.0003) contrasting the increased risk of specific sensitization by age 4 (odds ratio 3.52 [1.72-7.25], p = 0.0007) but not age 1.5. This study describes a FLG-associated pattern of atopic diseases...

  17. Striatal dopamine in Parkinson disease: A meta-analysis of imaging studies.

    Science.gov (United States)

    Kaasinen, Valtteri; Vahlberg, Tero

    2017-12-01

    A meta-analysis of 142 positron emission tomography and single photon emission computed tomography studies that have investigated striatal presynaptic dopamine function in Parkinson disease (PD) was performed. Subregional estimates of striatal dopamine metabolism are presented. The aromatic L-amino-acid decarboxylase (AADC) defect appears to be consistently smaller than the dopamine transporter and vesicular monoamine transporter 2 defects, suggesting upregulation of AADC function in PD. The correlation between disease severity and dopamine loss appears linear, but the majority of longitudinal studies point to a negative exponential progression pattern of dopamine loss in PD. Ann Neurol 2017;82:873-882. © 2017 American Neurological Association.

  18. A longitudinal study about the body image and psychosocial adjustment of breast cancer patients during the course of the disease.

    Science.gov (United States)

    Moreira, Helena; Canavarro, Maria Cristina

    2010-09-01

    The research of body image among breast cancer patients is characterized by some limitations, such as the lack of longitudinal studies or the absence of a multidimensional perspective of body image. This study intends to overcome these limitations, by examining the evolution of body image dimensions (investment, emotions and evaluations) from the period of surgery (T1) to 6-months after the treatment's ending (T2). It also aims to explore the predictors of body image at T2 and, simultaneously, the predictive role of initial body image to psychosocial adjustment at T2. A total of 56 breast cancer patients participated in both assessments and completed a battery of instruments that included measures of body image dimensions (appearance investment, self-consciousness of appearance, shame and appearance satisfaction) and psychosocial adjustment (quality of life and emotional distress). Within the dimensions of body image, only shame increased over time. In general, initial levels of investment predicted subsequent body image dimensions and having a mastectomy done was associated with higher shame and lower appearance satisfaction at T2. Initial body image did not predict later adjustment, with the exception of depression, where appearance investment played a relevant role. Our findings contributed to the advance of knowledge in this area, providing relevant data about the evolution of body image dimensions, its predictors and its predictive role on psychosocial adjustment among breast cancer patients. This study also suggested some clinical implications that can assist health professionals to implement strategies focused on body image throughout the disease.

  19. Spinal cord injury and Parkinson's disease: a population-based, propensity score-matched, longitudinal follow-up study.

    Science.gov (United States)

    Yeh, T-S; Huang, Y-P; Wang, H-I; Pan, S-L

    2016-12-01

    To investigate whether patients with spinal cord injury (SCI) are at an increased risk of developing Parkinson's disease (PD). A population-based, propensity score-matched, longitudinal follow-up cohort study. The study was conducted using the National Health Insurance (NHI) Research Database. A total of 10 125 patients with at least 2 ambulatory visits with a diagnosis of SCI in 2001 were enrolled in the SCI group. The non-SCI group comprised 10 125 propensity score-matched patients without SCI. The propensity scores were computed using a logistic regression model that included age, sex, comorbidities and socioeconomic status. The PD-free survival rates of the two groups were estimated using the Kaplan-Meier method. Stratified Cox proportional hazard regression was used to estimate the effect of SCI on subsequent occurrence of PD. During the 3-year follow-up period, 99 subjects in the SCI group and 59 in the non-SCI group developed PD. The hazard ratio of PD for the SCI group compared with the non-SCI group was 1.65 (95% confidence interval 1.16-2.33, P=0.0049). The PD-free survival rate for the SCI group was lower than that for the non-SCI group (P=0.0017). This study shows that SCI is associated with a subsequent increased risk of PD. Further studies are needed to elucidate the mechanism underlying this association.

  20. Longitudinal observations on circadian blood pressure variation in chronic kidney disease stages 3-5

    DEFF Research Database (Denmark)

    Elung-Jensen, T.; Strandgaard, S.; Kamper, Anne-Lise

    2008-01-01

    BACKGROUND: It has been suggested that status as a 'non-dipper' determined from 24-h blood pressure (BP) recordings is associated with increased risk of end-organ damage but little is known about the consistency of dipper status in renal patients. The present post hoc analysis evaluated dipper...... were classified as dippers or non-dippers based on the presence or absence of a nighttime reduction in both systolic and diastolic BP > 10%. Antihypertensive treatment aimed at an office BP determined from 24-h...

  1. Longitudinal assessment of high blood pressure in children with nonalcoholic fatty liver disease.

    Science.gov (United States)

    Schwimmer, Jeffrey B; Zepeda, Anne; Newton, Kimberly P; Xanthakos, Stavra A; Behling, Cynthia; Hallinan, Erin K; Donithan, Michele; Tonascia, James

    2014-01-01

    Nonalcoholic fatty liver disease (NAFLD) affects 9.6% of children and may put these children at elevated risk of high blood pressure and subsequent cardiovascular morbidity and mortality. Therefore, we sought to determine the prevalence of and risk factors for high blood pressure in children with NAFLD. Cohort study performed by the NIDDK NASH Clinical Research Network. There were 484 children with NAFLD ages 2 to 17 at enrollment; 382 children were assessed both at enrollment and 48 weeks afterwards. The main outcomes were high blood pressure at baseline and persistent high blood pressure at both baseline and 48 weeks. Prevalence of high blood pressure at baseline was 35.8% and prevalence of persistent high blood pressure was 21.4%. Children with high blood pressure were significantly more likely to have worse steatosis than children without high blood pressure (mild 19.8% vs. 34.2%, moderate 35.0% vs. 30.7%, severe 45.2% vs. 35.1%; P = 0.003). Higher body mass index, low-density lipoprotein, and uric acid were independent risk factors for high blood pressure (Odds Ratios: 1.10 per kg/m2, 1.09 per 10 mg/dL, 1.25 per mg/dL, respectively). Compared to boys, girls with NAFLD were significantly more likely to have persistent high blood pressure (28.4% vs.18.9%; P = 0.05). In conclusion, NAFLD is a common clinical problem that places children at substantial risk for high blood pressure, which may often go undiagnosed. Thus blood pressure evaluation, control, and monitoring should be an integral component of the clinical management of children with NAFLD.

  2. Longitudinal assessment of high blood pressure in children with nonalcoholic fatty liver disease.

    Directory of Open Access Journals (Sweden)

    Jeffrey B Schwimmer

    Full Text Available Nonalcoholic fatty liver disease (NAFLD affects 9.6% of children and may put these children at elevated risk of high blood pressure and subsequent cardiovascular morbidity and mortality. Therefore, we sought to determine the prevalence of and risk factors for high blood pressure in children with NAFLD.Cohort study performed by the NIDDK NASH Clinical Research Network. There were 484 children with NAFLD ages 2 to 17 at enrollment; 382 children were assessed both at enrollment and 48 weeks afterwards. The main outcomes were high blood pressure at baseline and persistent high blood pressure at both baseline and 48 weeks.Prevalence of high blood pressure at baseline was 35.8% and prevalence of persistent high blood pressure was 21.4%. Children with high blood pressure were significantly more likely to have worse steatosis than children without high blood pressure (mild 19.8% vs. 34.2%, moderate 35.0% vs. 30.7%, severe 45.2% vs. 35.1%; P = 0.003. Higher body mass index, low-density lipoprotein, and uric acid were independent risk factors for high blood pressure (Odds Ratios: 1.10 per kg/m2, 1.09 per 10 mg/dL, 1.25 per mg/dL, respectively. Compared to boys, girls with NAFLD were significantly more likely to have persistent high blood pressure (28.4% vs.18.9%; P = 0.05.In conclusion, NAFLD is a common clinical problem that places children at substantial risk for high blood pressure, which may often go undiagnosed. Thus blood pressure evaluation, control, and monitoring should be an integral component of the clinical management of children with NAFLD.

  3. A longitudinal study on lung disease in dental technicians: What has changed after seven years?

    Directory of Open Access Journals (Sweden)

    Derya Özdemir Dogan

    2013-10-01

    Full Text Available Objectives: The aim of this 7-year follow-up study was to determine respiratory changes in dental technicians. Material and Methods: In our region, in the year 2005, 36 dental technicians were evaluated with a cross-sectional study on respiratory occupational diseases, and in 2012 we evaluated them again. Inclusion of information on respiratory symptoms and demographic features questionnaires was applied. Pulmonary function tests (PFT were performed. Chest X-rays (CXR were evaluated according to the ILO-2000 classification. For the comparisons of the technicians' findings in 2005 and 2012, data analyses were performed with the Wilcoxon test in addition to descriptive statistical procedures. Results: In 2012, 19 out of the 36 technicians continued to work in the same place, so we were able to evaluate their findings. The prevalence of respiratory symptoms in dental technician was as follows: dyspnea 7 (37%, cough 6 (32%, and phlegm 5 (26%. According to ILO classifications in 2005, among the 36 technicians, 5 (13.8% had pneumoconiosis. At the end of 7 years, there were 9 pneumoconiosis cases among the 19 remaining technicians (47%. Thus, there was a statistically significant progression on the profusion of the radiologic findings (p < 0.005. Also there was a significant worsening on spirometric findings (p < 0.05. Conclusion: In dental technicians, a determination of both radiologic and functional progressions at the end of 7 years demonstrate that the primary and secondary preventive measures are necessary for these workplaces. Workplaces must be regularly controlled for worker health and hygiene.

  4. Impact of a child's cancer disease on parents' everyday life: a longitudinal study from Sweden.

    Science.gov (United States)

    Hovén, Emma; Grönqvist, Helena; Pöder, Ulrika; von Essen, Louise; Lindahl Norberg, Annika

    2017-01-01

    A child's cancer disease may disrupt the daily life of the affected family for a long period. The aim was to describe restrictions on parents' leisure activities and work/studies during and after the child's treatment. This study used data from a cohort of mothers and fathers (n = 246) of children diagnosed with cancer. Data was collected five times from two months after diagnosis to one year after end of treatment. Reports of restrictions were evaluated over time, between mothers and fathers, and in relation to parent-reported child symptom burden (The Memorial Symptom Assessment Scale) and partial post-traumatic stress disorder (PTSD) (The PTSD Checklist-Civilian Version). Two (51%) and four (45%) months after diagnosis, about half reported that their leisure activities were restricted at least some of the time. Corresponding percentages for restrictions on work/studies were 84% and 77%. One year after end of treatment, the great majority reported that their leisure activities (91%) and/or work/studies (76%) were never/seldom restricted. During treatment, more mothers than fathers reported restrictions on work/studies all/most of the time. After end of treatment, gender was only related to reports of restrictions among parents not reporting partial PTSD. More parents who reported being restricted all/most of the time also reported partial PTSD and/or a greater symptom burden for the child. Parents report frequent restrictions on everyday life during treatment. One year after end of treatment, parents report only a limited impact of the child's cancer on their leisure activities and work/studies. More parents who report restrictions also report partial PTSD and/or a greater child symptom burden. The effect of gender on restrictions varies depending on reports of partial PTSD. Future studies of gender differences regarding the impact of a child's cancer on parents' everyday life should thus consider mothers' and fathers' level of psychological distress.

  5. Longitudinal brain metabolic changes from amnestic mild cognitive impairment to Alzheimer's disease

    Science.gov (United States)

    Fouquet, Marine; Desgranges, Béatrice; Landeau, Brigitte; Duchesnay, Edouard; Mézenge, Florence; De La Sayette, Vincent; Viader, Fausto; Baron, Jean-Claude; Eustache, Francis; Chételat, Gaël

    2009-01-01

    A sensitive marker for monitoring progression of early Alzheimer’s Disease (AD) would help to develop and test new therapeutic strategies. The present study aimed at investigating brain metabolism changes over time, as potential monitoring marker, in patients with amnestic Mild Cognitive Impairment (aMCI), according to their clinical outcome (converters or non-converters), and in relation to their cognitive decline. Seventeen aMCI patients underwent MRI and 18FDG-PET scans both at inclusion and 18 months later. Baseline and follow-up PET data were corrected for partial volume effects and spatially normalized using MRI data, scaled to the vermis and compared using SPM2. ‘PET-PAC’ maps reflecting metabolic percent annual changes were created for correlation analyses with cognitive decline. In the whole sample, the greatest metabolic decrease concerned the posterior cingulate-precuneus area. Converters had significantly greater metabolic decrease than nonconverters in two ventro-medial prefrontal areas, the subgenual (BA25) and anterior cingulate (BA24/32). PET-PAC in BA25 and BA24/32 combined allowed complete between-group discrimination. BA25 PET-PAC significantly correlated with both cognitive decline and PET-PAC in the hippocampal region and temporal pole, while BA24/32 PET-PAC correlated with posterior cingulate PET-PAC. Finally, the metabolic change in BA8/9/10 was inversely related to that in BA25 and showed relative increase with cognitive decline, suggesting that compensatory processes may occur in this dorso-medial prefrontal region. The observed ventro-medial prefrontal disruption is likely to reflect disconnection from the hippocampus, both indirectly through the cingulum bundle and posterior cingulate cortex for BA24/32, and directly through the uncinate fasciculus for BA25. Altogether, our findings emphasize the potential of 18FDG-PET for monitoring early AD progression. PMID:19477964

  6. Longitudinal course of disease in a large cohort of myositis patients with autoantibodies recognizing the signal recognition particle

    Science.gov (United States)

    Werner, Jessie L.; Albayda, Jemyma; Paik, Julie; Danoff, Sonye K.; Casciola-Rosen, Livia; Christopher-Stine, Lisa; Mammen, Andrew L.

    2016-01-01

    Objective Patients with immune-mediated necrotizing myopathy (IMNM) often have autoantibodies recognizing the signal recognition particle (SRP) or HMG-CoA reductase (HMGCR). Here, we studied a cohort of anti-SRP patients to identify factors associated with disease severity and clinical improvement; we also compared the severity of weakness in those with anti-SRP versus anti-HMGCR autoantibodies. Methods All anti-SRP patients in the Johns Hopkins Myositis Cohort from 2002 to 2015 were included. Longitudinal information regarding proximal muscle strength, creatine kinase (CK) levels, and immunosuppressive therapy were recorded at each visit. Univariate and multivariate multilevel regression models were used to assess prognostic factors influencing recovery. Strength in the anti-SRP patients was compared to strength in 49 previously described anti-HMGCR subjects. Results Data from 37 anti-SRP patients and 380 total clinic visits was analyzed. Younger age at onset was associated with more severe weakness at the first visit (p=0.02) and all subsequent visits (p=0.002). Only 50% of patients reached near-full or full strength after 4 years of treatment and most of these continued to have elevated CK levels. Rituximab appeared to be effective in 13 of 17 anti-SRP patients. Anti-SRP patients were significantly weaker than those with anti-HMGCR autoantibodies (−1.3 strength points, p=0.001). Conclusions Younger age at onset is associated with more severe weakness in anti-SRP myositis. Furthermore, even among anti-SRP patients whose strength improved with immunosuppression, most had ongoing disease activity as demonstrated by elevated CK levels. Finally, anti-SRP patients were significantly weaker than anti-HMGCR patients, providing evidence that these autoantibodies are associated with distinct forms of IMNM. PMID:27111848

  7. Effect of traffic pollution on respiratory and allergic disease in adults: cross-sectional and longitudinal analyses

    Directory of Open Access Journals (Sweden)

    Whyatt Duncan

    2009-08-01

    Full Text Available Abstract Background Epidemiological research into the role of traffic pollution on chronic respiratory and allergic disease has focused primarily on children. Studies in adults, in particular those based on objective outcomes such as bronchial hyperresponsiveness, skin sensitisation, and lung function, are limited. Methods We have used an existing cohort of 2644 adults aged 18–70 living in Nottingham, UK, for whom baseline health and demographic data were collected in 1991 and computed two markers of exposure to traffic: distance between the home and nearest main road and modelled outdoor nitrogen dioxide (NO2 concentration at the home location. Using multiple regression techniques, we analysed cross-sectional associations with bronchial hyperresponsiveness, FEV1, spirometry-defined COPD, skin test positivity, total IgE and questionnaire-reported wheeze, asthma, eczema and hayfever in 2599 subjects, and longitudinal associations with decline in FEV1 in 1329 subjects followed-up nine years later in 2000. Results There were no significant cross-sectional associations between home proximity to the roadside or NO2 level on any of the outcomes studied (adjusted OR of bronchial hyperresponsiveness in relation to living ≤150 m vs >150 m from a road = 0.92, 95% CI 0.68 to 1.24. Furthermore, neither exposure was associated with a significantly greater decline in FEV1 over time (adjusted mean difference in ΔFEV1 for living ≤150 m vs >150 m of a road = 10.03 ml, 95% CI, -33.98 to 54.04. Conclusion This study found no evidence to suggest that living in close proximity to traffic is a major determinant of asthma, allergic disease or COPD in adults.

  8. Longitudinal study on clinical and microbial analysis of periodontal status in pregnancy

    Directory of Open Access Journals (Sweden)

    Fernanda Campos MACHADO

    Full Text Available Abstract This study was aimed to provide a longitudinal overview of the subgingival bacterial microbiome using fluorescence in situ hybridization (FISH technique, in women in the second trimester of pregnancy (between 14 and 24 weeks, and 48 h and 8 weeks postpartum. Of 31 women evaluated during pregnancy, 24 returned for the 48-h and 18 for their 8-week exams postpartum. Probing depth (PD, bleeding on probing, clinical attachment level, and presence of calculus were recorded. Subgingival plaque samples were collected, and FISH was used to identify the numbers of eight periodontal pathogens. Friedman test was used to compare differences between follow-up examinations, followed by a multiple comparison test for a post hoc pairwise comparison. Clinically, a significantly greater number of teeth with PD = 4–5 mm were found during pregnancy than on postpartum examinations. Microbial analysis showed a statistically significant decrease in cell count over the study period for Prevotella nigrescens. P. intermedia, Campylobacter rectus, and Porphyromonas gingivalis also decrease, although not significantly, and Aggregatibacter actinomycetemcomitans increased. No significant changes were found for Fusobacterium nucleatum, Treponema denticola, or Tannerella forsythia. Our data demonstrate a change in the subgingival microbiota during pregnancy, at least for P. nigrescens.

  9. Longitudinal Model Building Using Latent Transition Analysis: An Example Using School Bullying Data

    Directory of Open Access Journals (Sweden)

    Ji Hoon Ryoo

    2018-05-01

    Full Text Available Applications of latent transition analysis (LTA have emerged since the early 1990s, with numerous scientific findings being published in many areas, including social and behavioral sciences, education, and public health. Although LTA is effective as a statistical analytic tool for a person-centered model using longitudinal data, model building in LTA has often been subjective and confusing for applied researchers. To fill this gap in the literature, we review the components of LTA, recommend a framework of fitting LTA, and summarize what acceptable model evaluation tools should be used in practice. The proposed framework of fitting LTA consists of six steps depicted in Figure 1 from step 0 (exploring data to step 5 (fitting distal variables. We also illustrate the framework of fitting LTA with data on concerns about school bullying from a sample of 1,180 students ranging from 5th to 9th grade (mean age = 12.2 years, SD = 1.29 years at Time 1 over three semesters. We identified four groups of students with distinct patterns of bullying concerns, and found that their concerns about bullying decreased and narrowed to specific concerns about rumors, gossip, and social exclusion over time. The data and command (syntax files needed for reproducing the results using SAS PROC LCA and PROC LTA (Version 1.3.2 (2015 and Mplus 7.4 (Muthén and Muthén, 1998–2015 are provided as online supplementary materials.

  10. Longitudinal analysis of raccoon rabies in West Virginia, 2000–2015: a preliminary investigation

    Directory of Open Access Journals (Sweden)

    K. Bert Plants

    2018-04-01

    Full Text Available Animal borne rabies virus is a source of infection in humans, and raccoons (Procyon lotor are the primary terrestrial reservoir in West Virginia (WV. To assess the behavior and status of raccoon variant rabies virus (RRV cases in WV, a longitudinal analysis for the period 2000–2015 was performed, using data provided by the state Bureau of Public Health. The analytic approach used was negative binomial regression, with exclusion of those counties that had not experienced RRV cases in the study period, and with further examination of those counties where oral rabies vaccine (ORV baits had been distributed as compared with non-ORV counties. These analyses indicated that there had been a reduction in numbers of RRV positive animals over the study period, predominantly due to a decrease in raccoon infections. Non-raccoon hosts did not appear to have a similar decline, however. The rates of decline for the ORV zone were found to be significantly greater as compared to the non-ORV area. The study was limited by the lack of data for season or point location of animal collection, and by lack of surveillance effort data. Even so, this study has implications for the preventive measures currently being implemented, including expanded vaccination effort in domestic animals. Spatial analyses of RRV and further examination of the virus in non-raccoon hosts are warranted.

  11. Finite element analysis of lordosis restoration with anterior longitudinal ligament release and lateral hyperlordotic cage placement.

    Science.gov (United States)

    Uribe, Juan S; Harris, Jeffrey E; Beckman, J M; Turner, Alexander W L; Mundis, Gregory M; Akbarnia, Behrooz A

    2015-04-01

    Restoring sagittal alignment is an important factor in the treatment of spinal deformities. Recent investigations have determined that releasing the anterior longitudinal ligament (ALL) and placing hyperlordotic cages can increase lordosis, while minimizing need for 3 column osteotomies. The influences of parameters such as cage height and angle have not been determined. Finite element analysis was employed to assess the extent of lordosis achievable after placement of different sized lordotic cages. A 3-dimensional model of a L3-4 segment was used. Disc distraction was simulated by inserting interbody cages mid-body in the disc space. Analyses were performed in the following conditions: (1) intact, (2) ALL release, (3) ALL release + facetectomy, and (4) ALL release + posterior column osteotomy. Changes in segmental lordosis, disc height, foraminal height, and foraminal area were measured. After ALL resection and insertion of hyperlordotic cages, lordosis was increased in all cases. The lordosis achieved by the shorter cages was less due to posterior disc height maintained by the facet joints. A facetectomy increased segmental lordosis, but led to contact between the spinous processes. For some configurations, a posterior column osteotomy was required if the end goal was to match cage angle to intradiscal angle. Increased segmental lumbar lordosis is achievable with hyperlordotic cages after ALL resection. Increased cage height tended to increase the amount of lordosis achieved, although in some cases additional posterior bone resection was required to maximize lordosis. Further studies are needed to evaluate the impact on regional lumbar lordosis.

  12. Human values and beliefs and concern about climate change: a Bayesian longitudinal analysis.

    Science.gov (United States)

    Prati, Gabriele; Pietrantoni, Luca; Albanesi, Cinzia

    2018-01-01

    The aim of this study was to investigate the influence of human values on beliefs and concern about climate change using a longitudinal design and Bayesian analysis. A sample of 298 undergraduate/master students filled out the same questionnaire on two occasions at an interval of 2 months. The questionnaire included measures of beliefs and concern about climate change (i.e., perceived consequences, risk perception, and skepticism) and human values (i.e., the Portrait Values Questionnaire). After controlling for gender and the respective baseline score, universalism at Time 1 was associated with higher levels of perceived consequences of climate change and lower levels of climate change skepticism. Self-direction at Time 1 predicted Time 2 climate change risk perception and perceived consequences of climate change. Hedonism at Time 1 was associated with Time 2 climate change risk perception. The other human values at Time 1 were not associated with any of the measures of beliefs and concern about climate change at Time 2. The results of this study suggest that a focus on universalism and self-direction values seems to be a more successful approach to stimulate public engagement with climate change than a focus on other human values.

  13. A Longitudinal Analysis of Changes in Job Control and Mental Health.

    Science.gov (United States)

    Bentley, Rebecca J; Kavanagh, Anne; Krnjacki, Lauren; LaMontagne, Anthony D

    2015-08-15

    Deteriorating job control has been previously shown to predict poor mental health. The impact of improvement in job control on mental health is less well understood, yet it is of policy significance. We used fixed-effects longitudinal regression models to analyze 10 annual waves of data from a large Australian panel survey (2001-2010) to test within-person associations between change in self-reported job control and corresponding change in mental health as measured by the Mental Component Summary score of Short Form 36. We found evidence of a graded relationship; with each quintile increase in job control experienced by an individual, the person's mental health increased. The biggest improvement was a 1.55-point increase in mental health (95% confidence interval: 1.25, 1.84) for people moving from the lowest (worst) quintile of job control to the highest. Separate analyses of each of the component subscales of job control-decision authority and skill discretion-showed results consistent with those of the main analysis; both were significantly associated with mental health in the same direction, with a stronger association for decision authority. We conclude that as people's level of job control increased, so did their mental health, supporting the value of targeting improvements in job control through policy and practice interventions. © The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Protocol for the modeling the epidemiologic transition study: a longitudinal observational study of energy balance and change in body weight, diabetes and cardiovascular disease risk

    Directory of Open Access Journals (Sweden)

    Luke Amy

    2011-12-01

    Full Text Available Abstract Background The prevalence of obesity has increased in societies of all socio-cultural backgrounds. To date, guidelines set forward to prevent obesity have universally emphasized optimal levels of physical activity. However there are few empirical data to support the assertion that low levels of energy expenditure in activity is a causal factor in the current obesity epidemic are very limited. Methods/Design The Modeling the Epidemiologic Transition Study (METS is a cohort study designed to assess the association between physical activity levels and relative weight, weight gain and diabetes and cardiovascular disease risk in five population-based samples at different stages of economic development. Twenty-five hundred young adults, ages 25-45, were enrolled in the study; 500 from sites in Ghana, South Africa, Seychelles, Jamaica and the United States. At baseline, physical activity levels were assessed using accelerometry and a questionnaire in all participants and by doubly labeled water in a subsample of 75 per site. We assessed dietary intake using two separate 24-hour recalls, body composition using bioelectrical impedance analysis, and health history, social and economic indicators by questionnaire. Blood pressure was measured and blood samples collected for measurement of lipids, glucose, insulin and adipokines. Full examination including physical activity using accelerometry, anthropometric data and fasting glucose will take place at 12 and 24 months. The distribution of the main variables and the associations between physical activity, independent of energy intake, glucose metabolism and anthropometric measures will be assessed using cross-section and longitudinal analysis within and between sites. Discussion METS will provide insight on the relative contribution of physical activity and diet to excess weight, age-related weight gain and incident glucose impairment in five populations' samples of young adults at different stages

  15. What motivates early adolescents for school? A longitudinal analysis of associations between observed teaching and motivation

    NARCIS (Netherlands)

    Stroet, Kim; Opdenakker, Marie-Christine; Minnaert, Alexander

    For many early adolescent students, motivation for school declines after their transition to secondary education. Increasingly, the decisive importance of teachers in shaping early adolescents' motivation is stressed; thus far, however, both longitudinal and observational studies on this topic have

  16. Flight Test and Handling Qualities Analysis of a Longitudinal Flight Control System Using Multiobjective Techniques

    National Research Council Canada - National Science Library

    Anderson, John

    1998-01-01

    ...) and AFIT MXTOOLS toolboxes were used to produce the optimal, multiobjective designs. These designs were implemented for flight test on the Calspan VSS I Learjet, simulating the unstable longitudinal dynamics of an F-16 type aircraft...

  17. Employee identification before and after an internal merger: a longitudinal analysis

    NARCIS (Netherlands)

    Bartels, J.; Pruyn, A.T.H.; Jong, de M.D.T.

    2009-01-01

    Earlier studies have shown that perceived external prestige (PEP) and communication climate influence employees' overall organizational identification. This paper presents the results of a longitudinal study into the determinants of organizational identification at two organizational levels during

  18. Employee indentification before and after an internal merger: A longitudinal analysis

    NARCIS (Netherlands)

    Bartels, J.; Pruyn, Adriaan T.H.; de Jong, Menno D.T.

    2009-01-01

    Earlier studies have shown that perceived external prestige (PEP) and communication climate influence employees' overall organizational identification. This paper presents the results of a longitudinal study into the determinants of organizational identification at two organizational levels during

  19. Longitudinal analysis of music education on executive functions in primary school children

    NARCIS (Netherlands)

    Jaschke, A.C.; Honing, H.; Scherder, E.J.A.

    Background: Research on the effects of music education on cognitive abilities has generated increasing interest across the scientific community. Nonetheless, longitudinal studies investigating the effects of structured music education on cognitive sub-functions are still rare. Prime candidates for

  20. Safe RESIDential Environments? A longitudinal analysis of the influence of crime-related safety on walking

    OpenAIRE

    Foster, Sarah; Hooper, Paula; Knuiman, Matthew; Christian, Hayley; Bull, Fiona; Giles-Corti, Billie

    2016-01-01

    Background Numerous cross-sectional studies have investigated the premise that the perception of crime will cause residents to constrain their walking; however the findings to date are inconclusive. In contrast, few longitudinal or prospective studies have examined the impact of crime-related safety on residents walking behaviours. This study used longitudinal data to test whether there is a causal relationship between crime-related safety and walking in the local neighbourhood. Methods Parti...

  1. Like a virgin (mother): analysis of data from a longitudinal, US population representative sample survey

    OpenAIRE

    Herring, Amy H; Attard, Samantha M; Gordon-Larsen, Penny; Joyner, William H; Halpern, Carolyn T

    2013-01-01

    Objective To estimate the incidence of self report of pregnancy without sexual intercourse (virgin pregnancy) and factors related to such reporting, in a population representative group of US adolescents and young adults. Design Longitudinal, population representative sample survey. Setting Nationally representative, multiethnic National Longitudinal Study of Adolescent Health, United States. Participants 7870 women enrolled at wave I (1995) and completing the most recent wave of data collect...

  2. Neoplastic pericardial disease. Analysis of 26 patients

    Directory of Open Access Journals (Sweden)

    Helena Nogueira Soufen

    1999-01-01

    Full Text Available PURPOSE: To characterize patients with neoplastic pericardial disease diagnosed by clinical presentation, complementary test findings, and the histological type of tumor. METHODS: Twenty-six patients with neoplastic pericardial disease were retrospectively analyzed. RESULTS: Clinical manifestations and abnormalities in chest roentgenograms and electrocardiograms were frequent, but were not specific. Most patients underwent surgery. There was a high positivity of the pericardial biopsy when associated with the cytological analysis of the pericardial liquid used to determine the histological type of the tumor, particularly when the procedure was performed with the aid of pericardioscopy. CONCLUSION: The correct diagnosis of neoplastic pericardial disease involves suspicious but nonspecific findings during clinical examination and in screen tests. The suspicious findings must be confirmed through more invasive diagnostic approaches, in particular pericardioscopy with biopsy and cytological study.

  3. Big data in multiple sclerosis: development of a web-based longitudinal study viewer in an imaging informatics-based eFolder system for complex data analysis and management

    Science.gov (United States)

    Ma, Kevin; Wang, Ximing; Lerner, Alex; Shiroishi, Mark; Amezcua, Lilyana; Liu, Brent

    2015-03-01

    In the past, we have developed and displayed a multiple sclerosis eFolder system for patient data storage, image viewing, and automatic lesion quantification results stored in DICOM-SR format. The web-based system aims to be integrated in DICOM-compliant clinical and research environments to aid clinicians in patient treatments and disease tracking. This year, we have further developed the eFolder system to handle big data analysis and data mining in today's medical imaging field. The database has been updated to allow data mining and data look-up from DICOM-SR lesion analysis contents. Longitudinal studies are tracked, and any changes in lesion volumes and brain parenchyma volumes are calculated and shown on the webbased user interface as graphical representations. Longitudinal lesion characteristic changes are compared with patients' disease history, including treatments, symptom progressions, and any other changes in the disease profile. The image viewer is updated such that imaging studies can be viewed side-by-side to allow visual comparisons. We aim to use the web-based medical imaging informatics eFolder system to demonstrate big data analysis in medical imaging, and use the analysis results to predict MS disease trends and patterns in Hispanic and Caucasian populations in our pilot study. The discovery of disease patterns among the two ethnicities is a big data analysis result that will help lead to personalized patient care and treatment planning.

  4. Social relationships and cognitive decline: a systematic review and meta-analysis of longitudinal cohort studies.

    Science.gov (United States)

    Kuiper, Jisca S; Zuidersma, Marij; Zuidema, Sytse U; Burgerhof, Johannes Gm; Stolk, Ronald P; Oude Voshaar, Richard C; Smidt, Nynke

    2016-08-01

    Although poor social relationships are assumed to contribute to cognitive decline, meta-analytic approaches have not been applied. Individual study results are mixed and difficult to interpret due to heterogeneity in measures of social relationships. We conducted a systematic review and meta-analysis to investigate the relation between poor social relationships and cognitive decline. MEDLINE, Embase and PsycINFO were searched for longitudinal cohort studies examining various aspects of social relationships and cognitive decline in the general population. Odds ratios (ORs) with 95% confidence intervals (CIs) were pooled using random effects meta-analysis. Sources of heterogeneity were explored and likelihood of publication bias was assessed. We stratified analyses according to three aspects of social relationships: structural, functional and a combination of these. We identified 43 articles. Poor social relationships predicted cognitive decline; for structural (19 studies): pooled OR: 1.08 (95% CI: 1.05-1.11); functional (8 studies): pooled OR: 1.15 (95% CI: 1.00-1.32); and combined measures (7 studies): pooled OR: 1.12 (95% CI: 1.01-1.24). Meta-regression and subgroup analyses showed that the heterogeneity could be explained by the type of social relationship measurement and methodological quality of included studies. Despite heterogeneity in study design and measures, our meta-analyses show that multiple aspects of social relationships are associated with cognitive decline. As evidence for publication bias was found, the association might be overestimated and should therefore be interpreted with caution. Future studies are needed to better define the mechanisms underlying these associations. Potential causality of this prognostic association should be examined in future randomized controlled studies. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

  5. Comparison of bias-corrected covariance estimators for MMRM analysis in longitudinal data with dropouts.

    Science.gov (United States)

    Gosho, Masahiko; Hirakawa, Akihiro; Noma, Hisashi; Maruo, Kazushi; Sato, Yasunori

    2017-10-01

    In longitudinal clinical trials, some subjects will drop out before completing the trial, so their measurements towards the end of the trial are not obtained. Mixed-effects models for repeated measures (MMRM) analysis with "unstructured" (UN) covariance structure are increasingly common as a primary analysis for group comparisons in these trials. Furthermore, model-based covariance estimators have been routinely used for testing the group difference and estimating confidence intervals of the difference in the MMRM analysis using the UN covariance. However, using the MMRM analysis with the UN covariance could lead to convergence problems for numerical optimization, especially in trials with a small-sample size. Although the so-called sandwich covariance estimator is robust to misspecification of the covariance structure, its performance deteriorates in settings with small-sample size. We investigated the performance of the sandwich covariance estimator and covariance estimators adjusted for small-sample bias proposed by Kauermann and Carroll ( J Am Stat Assoc 2001; 96: 1387-1396) and Mancl and DeRouen ( Biometrics 2001; 57: 126-134) fitting simpler covariance structures through a simulation study. In terms of the type 1 error rate and coverage probability of confidence intervals, Mancl and DeRouen's covariance estimator with compound symmetry, first-order autoregressive (AR(1)), heterogeneous AR(1), and antedependence structures performed better than the original sandwich estimator and Kauermann and Carroll's estimator with these structures in the scenarios where the variance increased across visits. The performance based on Mancl and DeRouen's estimator with these structures was nearly equivalent to that based on the Kenward-Roger method for adjusting the standard errors and degrees of freedom with the UN structure. The model-based covariance estimator with the UN structure under unadjustment of the degrees of freedom, which is frequently used in applications

  6. Chinese social media analysis for disease surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Xiaohui [Wuhan Univ., Wuhan (China); Yang, Nanhai [Wuhan Univ., Wuhan (China); Wang, Zhibo [Wuhan Univ., Wuhan (China); East China Institute of Technology, Nanchang (China); Hu, Cheng [Wuhan Univ., Wuhan (China); Zhu, Weiping [Wuhan Univ., Wuhan (China); Li, Hanjie [Wuhan Univ., Wuhan (China); Ji, Yujie [Wuhan Univ., Wuhan (China); Liu, Cheng [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-11

    Here, it is reported that there are hundreds of thou- sands of deaths caused by seasonal flu all around the world every year. More other diseases such as chickenpox, malaria, etc. are also serious threats to people’s physical and mental health. There are 250,000–500,000 deaths every year around the world. Therefore proper techniques for disease surveillance are highly demanded. Recently, social media analysis is regarded as an efficient way to achieve this goal, which is feasible since growing number of people have been posting their health information on social media such as blogs, personal websites, etc. Previous work on social media analysis mainly focused on English materials but hardly considered Chinese materials, which hinders the application of such technique to Chinese peo- ple. In this paper, we proposed a new method of Chinese social media analysis for disease surveillance. More specifically, we compared different kinds of methods in the process of classification and then proposed a new way to process Chinese text data. The Chinese Sina micro-blog data collected from September to December 2013 are used to validate the effectiveness of the proposed method. The results show that a high classification precision of 87.49 % in average has been obtained. Comparing with the data from the authority, Chinese National Influenza Center, we can predict the outbreak time of flu 5 days earlier.

  7. The association between disease activity and NT-proBNP in 238 patients with rheumatoid arthritis: a 10-year longitudinal study

    Science.gov (United States)

    Provan, Sella A; Angel, Kristin; Ødegård, Sigrid; Mowinckel, Petter; Atar, Dan; Kvien, Tore K

    2008-01-01

    Introduction Disease activity in patients with rheumatoid arthritis (RA) is associated with increased cardiovascular morbidity and mortality, of which N-terminal pro-brain natriuretic peptide (NT-proBNP) is a predictor. Our objective was to examine the cross-sectional and longitudinal associations between markers of inflammation, measures of RA disease activity, medication used in the treatment of RA, and NT-proBNP levels (dependent variable). Methods Two hundred thirty-eight patients with RA of less than 4 years in duration were followed longitudinally with three comprehensive assessments of clinical and radiographic data over a 10-year period. Serum samples were frozen and later batch-analyzed for NT-proBNP levels and other biomarkers. Bivariate, multivariate, and repeated analyses were performed. Results C-reactive protein (CRP) levels at baseline were cross-sectionally associated with NT-proBNP levels after adjustment for age and gender (r2 adjusted = 0.23; P < 0.05). At the 10-year follow-up, risk factors for cardiovascular disease were recorded. Duration of RA and CRP levels were independently associated with NT-proBNP in the final model that was adjusted for gender, age, and creatinine levels (r2 adjusted = 0.38; P < 0.001). In the longitudinal analyses, which adjusted for age, gender, and time of follow-up, we found that repeated measures of CRP predicted NT-proBNP levels (P < 0.001). Conclusion CRP levels are linearly associated with levels of NT-proBNP in cross-sectional and longitudinal analyses of patients with RA. The independent associations of NT-proBNP levels and markers of disease activity with clinical cardiovascular endpoints need to be further investigated. PMID:18573197

  8. DETERMINANTS OF HEALTHCARE EXPENDITURE ON HUMAN CAPITAL AND ECONOMIC GROWTH IN BANGLADESH: A LONGITUDINAL DATA ANALYSIS FROM 1995-2010

    OpenAIRE

    SHONGKOUR ROY

    2014-01-01

    The objective of this study was to examine the determinants of healthcare expenditure in Bangladesh between 1995 and 2010 byapplying the World development indicator data. First, I developed an empirical model for longitudinal data analysis to determinant thehealthcare expenditure under the human capital and economic growth. Next, I explored the dynamic relationships among healthcareexpenditure, human capital and economic growth usingOLSmodel. The expenditure in private healthcare was 2.3% and...

  9. Lifestyle factors, medication use and risk for ischaemic heart disease hospitalisation: a longitudinal population-based study.

    Directory of Open Access Journals (Sweden)

    Anthony S Gunnell

    Full Text Available BACKGROUND: Lifestyle factors have been implicated in ischaemic heart disease (IHD development however a limited number of longitudinal studies report results stratified by cardio-protective medication use. PURPOSE: This study investigated the influence of self-reported lifestyle factors on hospitalisation for IHD, stratified by blood pressure and/or lipid-lowering therapy. METHODS: A population-based cohort of 14,890 participants aged 45+ years and IHD-free was identified from the Western Australian Health and wellbeing Surveillance System (2004 to 2010 inclusive, and linked with hospital administrative data. Adjusted hazard ratios for future IHD-hospitalisation were estimated using Cox regression. RESULTS: Current smokers remained at higher risk for IHD-hospitalisation (adjusted HR=1.57; 95% CI: 1.22-2.03 after adjustment for medication use, as did those considered overweight (BMI=25-29 kg/m(2; adjusted HR=1.28; 95% CI: 1.04-1.57 or obese (BMI of ≥30 kg/m(2; adjusted HR=1.31; 95% CI: 1.03-1.66. Weekly leisure-time physical activity (LTPA of 150 minutes or more and daily intake of 3 or more fruit/vegetable servings reduced risk by 21% (95% CI: 0.64-0.97 and 26% (95% CI: 0.58-0.96 respectively. Benefits of LTPA appeared greatest in those on blood pressure lowering medication (adjusted HR=0.50; 95% CI: 0.31-0.82 [for LTPA=150 mins]. IHD risk in smokers was most pronounced in those taking neither medication (adjusted HR=2.00; 95% CI: 1.41-2.83. CONCLUSION: This study confirms the contribution of previously reported lifestyle factors towards IHD hospitalisation, even after adjustment for antihypertensive and lipid-lowering medication use. Medication stratified results suggest that IHD risks related to LTPA and smoking may differ according to medication use.

  10. Disease management programs for patients with COPD in Germany: a longitudinal evaluation of routinely collected patient records.

    Science.gov (United States)

    Mehring, Michael; Donnachie, Ewan; Fexer, Johannes; Hofmann, Frank; Schneider, Antonius

    2014-07-01

    The primary aim of the disease management program (DMP) for patients with COPD is to improve health outcomes and thereby to reduce overall costs. Six years after its introduction in Germany, no consensus has yet been reached as to whether the DMP has been effective in reaching these goals. The objective of the study was an evaluation of the DMP for COPD in Bavaria using routinely collected subject medical records. A longitudinal population-based study, comparing the total DMP population of up to 86,560 patients with a stable cohort of 17,549 subjects over a period of 5 years. The effect of subject dropout in the cohort is further estimated by means of inverse probability weighting. The proportion of subjects in the total population who were prescribed and received treatment with oral corticosteroids declined at a constant rate of 1.0% per year (P management education. While the proportion of smokers in the total population remained constant because of the effect of newly enrolled subjects, the proportion of smokers decreased significantly even after dropout adjustment, from 29% to 21%. The occurrence of exacerbations decreased steadily at a rate of 0.9% (total population) or 0.7% (cohort) per year. While the occurrence of emergency hospital admissions decreased in the total population, an increase was observed within the cohort. Summarizing all results leads to the suggestion that the German DMP for COPD has been effective in enhancing the quality of care in regard to an improved adherence to guidelines, pharmacotherapy, exacerbations, and self-management education. However, the DMP was not able to prevent an increase in emergency hospital admissions for the stable population in the cohort. Copyright © 2014 by Daedalus Enterprises.

  11. Accuracy of Consecutive Fecal Calprotectin Measurements to Predict Relapse in Inflammatory Bowel Disease Patients Under Maintenance With Anti-TNF Therapy: A Prospective Longitudinal Cohort Study.

    Science.gov (United States)

    Ferreiro-Iglesias, Rocio; Barreiro-de Acosta, Manuel; Lorenzo-Gonzalez, Aurelio; Dominguez-Muñoz, Juan E

    2018-03-01

    Predicting relapse in inflammatory bowel disease (IBD) patients could allow early changes in therapy. We aimed at evaluating the accuracy of consecutive fecal calprotectin (FC) measurements to predict flares in IBD patients under maintenance treatment with anti-tumor necrosis factor (TNF) drugs. A prospective longitudinal cohort study with 16-month follow-up period was designed. IBD patients in clinical remission for at least 6 months under anti-TNF therapy were included. FC was quantified at 4-month intervals for 1 year, and patients were clinically evaluated for relapse at 2-month intervals. Diagnostic accuracy of FC for predicting relapse was evaluated by receiver-operating characteristic curve analysis. In total, 95 of 106 included patients finalized the study and were analyzed (median age 44 y, 50.5% female, 75% with Crohn's disease). A total of 30 patients (31.6%) had a relapse over follow-up. FC concentration was significantly higher in patients who relapsed (477 μg/g) than in patients who maintained in remission (65 μg/g) (Ppredict remission was 130 μg/g (negative predictive value of 100%), and 300 μg/g to predict relapse (positive predictive value of 78.3%). FC is a good predictor of clinical relapse and a particularly good predictor of remission over the following 4 months in patients with IBD on maintenance therapy with anti-TNF drugs. FC levels 300 μg/g allow predicting relapse with a high probability at any time over the following 4 months.

  12. Eating frequency in relation to BMI in very young children: a longitudinal analysis.

    Science.gov (United States)

    Taylor, Rachael W; Iosua, Ella; Heath, Anne-Louise M; Gray, Andrew R; Taylor, Barry J; Lawrence, Julie A; Hanna, Maha; Cameron, Sonya L; Sayers, Rachel; Galland, Barbara

    2017-06-01

    Eating less frequently is associated with increased obesity risk in older children but data are potentially confounded by reverse causation, where bigger children eat less often in an effort to control their weight. Longitudinal data, particularly in younger children, are scarce. We aimed to determine whether eating frequency (meals and snacks) at 2 years of age is associated with past, current or subsequent BMI. Cohort analysis of a randomised controlled trial. Eating frequency at 2 years of age was estimated using 48 h diaries that recorded when each child ate meals and snacks (parent-defined) in five-minute blocks. Body length/height and weight were measured at 1, 2 and 3·5 years of age. Linear regression assessed associations between the number of eating occasions and BMI Z-score, before and after adjustment for potential confounding variables. Prevention of Overweight in Infancy (POI) study, Dunedin, New Zealand. Children (n 371) aged 1-3·5 years. On average, children ate 5·5 (sd 1·2) times/d at 2 years of age, with most children (88-89 %) eating 4-7 times/d. Eating frequency at 2 years was not associated with current (difference in BMI Z-score per additional eating occasion; 95 % CI: -0·02; -0·10, 0·05) or subsequent change (0·02; -0·03, 0·06) in BMI. Similarly, BMI at age 1 year did not predict eating frequency at 2 years of age (difference in eating frequency per additional BMI Z-score unit; 95 % CI: -0·03; -0·19, 0·13). Number of eating occasions per day was not associated with BMI in young children in the present study.

  13. Monthly food insecurity assessment in rural mkushi district, Zambia: a longitudinal analysis

    Directory of Open Access Journals (Sweden)

    Muzi Na

    2017-03-01

    Full Text Available Abstract Background Perception-based scales are widely used for household food insecurity (HFI assessment but were only recently added in national surveys. The frequency of assessments needed to characterize dynamics in HFI over time is largely unknown. The study aims to examine longitudinal changes in monthly reported HFI at both population- and household-level. Methods A total of 157 households in rural Mkushi District whose children were enrolled in the non-intervened arm of an efficacy trial of biofortified maize were included in the analysis. HFI was assessed by a validated 8-item perception-based Likert scale on a monthly basis from October 2012 to March 2013 (6 visits, characterizing mostly the lean season. An HFI index was created by summing scores over the Likert scale, with a possible range of 0–32. The Wilcoxon matched signed-ranks test was used to compare distribution of HFI index between visits. A random effect model was fit to quantify the sources of variance in indices at household level. Results The median [IQR] HFI index was 4.5 [2, 8], 5 [1, 8], 4 [1, 7], 4 [1, 6], 3 [1, 7] and 4 [1, 6] at the six monthly visits, respectively. HFI index was significantly higher in visit 1 and 2 than visit 3–6 and on average the index decreased by 0.25 points per visit. Within- and between-household variance in the index were 10.6 and 8.8, respectively. Conclusions The small change in mean monthly HFI index over a single lean season indicated that a seasonal HFI measure may be sufficient for monitoring purposes at population level. Yet, higher variation within households suggests that repeated assessments may be required to avoid risk of misclassification at household level and to target households with the greatest risk of food insecurity.

  14. Longitudinal Analysis of Music Education on Executive Functions in Primary School Children

    Science.gov (United States)

    Jaschke, Artur C.; Honing, Henkjan; Scherder, Erik J. A.

    2018-01-01

    Background: Research on the effects of music education on cognitive abilities has generated increasing interest across the scientific community. Nonetheless, longitudinal studies investigating the effects of structured music education on cognitive sub-functions are still rare. Prime candidates for investigating a relationship between academic achievement and music education appear to be executive functions such as planning, working memory, and inhibition. Methods: One hundred and forty-seven primary school children, Mage = 6.4 years, SD = 0.65 were followed for 2.5 years. Participants were randomized into four groups: two music intervention groups, one active visual arts group, and a no arts control group. Neuropsychological tests assessed verbal intelligence and executive functions. Additionally, a national pupil monitor provided data on academic performance. Results: Children in the visual arts group perform better on visuospatial memory tasks as compared to the three other conditions. However, the test scores on inhibition, planning and verbal intelligence increased significantly in the two music groups over time as compared to the visual art and no arts controls. Mediation analysis with executive functions and verbal IQ as mediator for academic performance have shown a possible far transfer effect from executive sub-function to academic performance scores. Discussion: The present results indicate a positive influence of long-term music education on cognitive abilities such as inhibition and planning. Of note, following a two-and-a-half year long visual arts program significantly improves scores on a visuospatial memory task. All results combined, this study supports a far transfer effect from music education to academic achievement mediated by executive sub-functions. PMID:29541017

  15. Longitudinal Analysis of Music Education on Executive Functions in Primary School Children

    Directory of Open Access Journals (Sweden)

    Artur C. Jaschke

    2018-02-01

    Full Text Available Background: Research on the effects of music education on cognitive abilities has generated increasing interest across the scientific community. Nonetheless, longitudinal studies investigating the effects of structured music education on cognitive sub-functions are still rare. Prime candidates for investigating a relationship between academic achievement and music education appear to be executive functions such as planning, working memory, and inhibition.Methods: One hundred and forty-seven primary school children, Mage = 6.4 years, SD = 0.65 were followed for 2.5 years. Participants were randomized into four groups: two music intervention groups, one active visual arts group, and a no arts control group. Neuropsychological tests assessed verbal intelligence and executive functions. Additionally, a national pupil monitor provided data on academic performance.Results: Children in the visual arts group perform better on visuospatial memory tasks as compared to the three other conditions. However, the test scores on inhibition, planning and verbal intelligence increased significantly in the two music groups over time as compared to the visual art and no arts controls. Mediation analysis with executive functions and verbal IQ as mediator for academic performance have shown a possible far transfer effect from executive sub-function to academic performance scores.Discussion: The present results indicate a positive influence of long-term music education on cognitive abilities such as inhibition and planning. Of note, following a two-and-a-half year long visual arts program significantly improves scores on a visuospatial memory task. All results combined, this study supports a far transfer effect from music education to academic achievement mediated by executive sub-functions.

  16. Analysis of aspects of quality of life in teachers' voice after discharged: longitudinal study.

    Science.gov (United States)

    Ferreira, Josiane Mendes; Campos, Nathália Ferreira; Bassi, Iara Barreto; Santos, Marco Aurélio Rocha; Teixeira, Letícia Caldas; Gama, Ana Cristina Côrtes

    2013-01-01

    To evaluate the long-term effects of voice therapy on the life quality of teachers who were discharged or abandoned the voice therapy for dysphonia. This was a longitudinal study based on analysis of assessments with teachers of municipal schools in Belo Horizonte, who were referred to voice therapy and were discharged or abandoned the speech-language therapy for more than six months. A total of 33 teachers in the discharged group and 20 teachers in the abandoned group were contacted by phone and invited to participate in the study by answering the Voice activity and participation profile, which was forwarded to the researchers and sent via letter. At the moment of the pre speech therapy, the discharged and abandoned groups were homogeneous, except in relation to daily communication parameter. Comparing the discharged group in the pre and post speech-language therapy, it was showed improvements in social communication parameter as well as in the total score. The discharged group presented worsening in self-perception parameter when comparing the average values in the post therapy and current moments, and the group abandoned presented worsening in work, social communication and total score when comparing to the average values in the pre therapy and current moments. The discharged and abandoned groups differ in the present moment in all investigated parameters. Speech-language therapy for dysphonia have long term positive effects on life quality and voice of teachers who were soon discharged from the therapy and in a period of two years on average. Teachers who have abandoned treatment and did not obtain improvement in the voice showed negative impact in life quality and voice in a time of 2 years and 2 months on average.

  17. Verbal and physical client aggression - A longitudinal analysis of professional caregivers' psychophysiological stress response and burnout.

    Science.gov (United States)

    Kind, Nina; Eckert, Anne; Steinlin, Célia; Fegert, Jörg M; Schmid, Marc

    2018-05-02

    We investigated the impact of verbal and physical client aggression on risk of developing high hair cortisol concentration (HCC) as an indicator of chronic stress exposure and burnout in a Swiss population of professional caregivers working in youth residential care. Participants (n = 121; 62.0% women) reported on client aggression and burnout symptoms and provided hair samples at four annual sampling points. HCC was determined in the first 1.5 cm hair segment. Sociodemographic variables, private stressors, burnout symptoms, and HCC were compared between participants reporting either 'no aggression', 'verbal' aggression, or 'verbal + physical' aggression. Cox proportional hazards regressions were calculated to compute hazard ratios (HR) and 95% confidence intervals (CI) for the association between client aggression and risk of high HCC or burnout over the course of three years. Professional caregivers reporting 'verbal + physical' aggression had higher HCC, more cognitive burnout symptoms, and greater burden in interpersonal domains. Both 'verbal' and 'verbal + physical' aggression were positively associated with burnout risk (verbal: HR = 1.83; 95% CI = 1.27-2.65; verbal + physical: HR = 2.44, 95% CI = 1.56-3.84). 'Verbal + physical' aggression was positively associated with risk of high HCC (HR = 1.58; 95% CI = 1.07-2.36). This longitudinal analysis suggested that psychophysiological stress response is primarily associated with combined verbal and physical aggression. The emotional wearing-down associated with verbal aggression should however not be disregarded. Our exploratory findings could have implications for youth welfare policy, clinical child psychiatry, and future research. Copyright © 2018. Published by Elsevier Ltd.

  18. Factors Associated With Changes in Magnesium Levels in Asymptomatic Neonates: A Longitudinal Analysis.

    Science.gov (United States)

    Mehta, Yogesh; Shitole, Charudatta; Setia, Maninder Singh

    2016-02-01

    Neonates and infants with hypomagnesemia present with seizures and psychomotor delay. The present study evaluated the changes in magnesium (Mg) levels and factors associated with these in the first three days of life. We monitored 50 clinically asymptomatic neonates; they were not given any magnesium supplements even if they had hypomagnesemia at baseline. The variables analysed were: serum Mg; gestational age; birth weight; length; and the ponderal index. We used random effects (RE) models for longitudinal analysis of these data. The mean standard deviation (SD) gestational age was 36.3 (3.6) weeks and the mean (SD) weight was 2604.2 (754.4) grams. About 31% of the neonates had hypomagnesemia (< 1.6 mg/dL) on day one; however, all had normal magnesium levels by day three of life (P < 0.001). At birth, after adjusting for intrauterine growth retardation status (IUGR), serum Mg levels were lower by 0.0097 mg/dL (95% CI: -0.019 to -0.0003) per 100 grams increase in weight of the neonate. After adjusting for IUGR status, the mean increase in the serum Mg levels was 0.14 mg/dL (95% confidence intervals [CI]: 0.10 to 0.18) per day. The per-day increase in magnesium levels was significantly higher in low birth weight babies (0.10, 95% CI: 0.01 to 0.18) compared with normal birth weight babies. Asymptomatic neonates may have a high prevalence of hypomagnesemia; however, the levels become normal without any magnesium supplementation. Even though regular monitoring of magnesium levels is useful, no supplements are required - particularly in clinically asymptomatic neonates.

  19. Time course of neck-shoulder pain among workers: A longitudinal latent class growth analysis.

    Science.gov (United States)

    Hallman, David M; Rasmussen, Charlotte D Nørregaard; Jørgensen, Marie Birk; Holtermann, Andreas

    2018-01-01

    Objectives The aims of this study were to (i) identify trajectories of neck-shoulder pain (NSP) over one year in an occupational population and (ii) determine whether these trajectories are predicted by NSP characteristics as well as personal and occupational factors at baseline. Methods This longitudinal study was conducted among Danish workers (N=748) from 2012-2014. Text messages were used to collect frequent data on NSP over one year (14 waves in total). Peak NSP intensity in the past month was rated on a 0-10 numeric scale. A baseline questionnaire covered NSP characteristics (pain intensity, duration, comorbidity, pain medication, and pain interference) as well as personal (age, gender, body mass index) and occupational (seniority, work type, physical strain at work) factors. Latent class growth analysis was used to distinguish trajectories of NSP. Multivariate regression models with odds ratios (OR) were constructed to predict trajectories of NSP. Results Six distinct trajectories of NSP were identified (asymptomatic 11%, very low NSP 10%, low recovering NSP 18%, moderate recovering NSP 28%, strong fluctuating NSP 24% and severe persistent NSP 9% of the workers). Female gender, age, physical strain at work, NSP intensity and duration, pain medication, and pain interference in daily work at baseline were positively associated with severe persistent NSP and strong fluctuating NSP (all P<0.05). Altogether, personal and occupational factors accounted for 14% of the variance, while NSP characteristics accounted for 54%. Conclusions In an occupational sample, six distinct trajectories of NSP were identified. Physical strain at work appears to be a pertinent occupational factor predicting strong fluctuating and severe persistent NSP.

  20. Longitudinal Analysis of Music Education on Executive Functions in Primary School Children.

    Science.gov (United States)

    Jaschke, Artur C; Honing, Henkjan; Scherder, Erik J A

    2018-01-01

    Background: Research on the effects of music education on cognitive abilities has generated increasing interest across the scientific community. Nonetheless, longitudinal studies investigating the effects of structured music education on cognitive sub-functions are still rare. Prime candidates for investigating a relationship between academic achievement and music education appear to be executive functions such as planning, working memory, and inhibition. Methods: One hundred and forty-seven primary school children, M age = 6.4 years, SD = 0.65 were followed for 2.5 years. Participants were randomized into four groups: two music intervention groups, one active visual arts group, and a no arts control group. Neuropsychological tests assessed verbal intelligence and executive functions. Additionally, a national pupil monitor provided data on academic performance. Results: Children in the visual arts group perform better on visuospatial memory tasks as compared to the three other conditions. However, the test scores on inhibition, planning and verbal intelligence increased significantly in the two music groups over time as compared to the visual art and no arts controls. Mediation analysis with executive functions and verbal IQ as mediator for academic performance have shown a possible far transfer effect from executive sub-function to academic performance scores. Discussion: The present results indicate a positive influence of long-term music education on cognitive abilities such as inhibition and planning. Of note, following a two-and-a-half year long visual arts program significantly improves scores on a visuospatial memory task. All results combined, this study supports a far transfer effect from music education to academic achievement mediated by executive sub-functions.

  1. Comparative analysis of maximum renal longitudinal length with positional changes on ultrasound with multiplanar reconstructed MR image in Korea Adults

    International Nuclear Information System (INIS)

    Jang, Yun Hee; Cho, Bum Sang; Kang, Min Ho; Kang, Woo Young; Lee, Jisun; Kim, Yook; Lee, Soo Hyun; Lee, Soo Jung; Lee, Jin Yong

    2016-01-01

    The purpose of this study was to determine a suitable position in which the measured length on ultrasound is close to the true renal length obtained through a multiplanar reconstructed MR image. A total of 33 individuals (males: 15, females: 18) without any underlying renal disease were included in the present study. Renal length was measured as the longest axis at the level of the renal hilum in three positions-supine, lateral decubitus, and prone, respectively. With a 3.0 T MR scanner, 3D eTHRIVE was acquired. Subsequently, the maximum longitudinal length of both the kidneys was measured through multiplanar reconstructed MR images. Paired t-test was used to compare the renal length obtained from ultrasonographic measurement with the length obtained through multiplanar reconstructed MR images. Our study demonstrated significant difference between sonographic renal length in three positions and renal length through MRI (p < 0.001). However, the longest longitudinal length of right kidney among the measured three values by ultrasound was statistically similar to the renal length measured by reconstructed MR image. Among them, the lateral decubitus position showed the strongest correlation with true renal length (right: 0.887; left: 0.849). We recommend measurement of the maximum renal longitudinal length in all possible positions on ultrasonography. If not allowed, the best measurement is on the lateral decubitus showing the strongest correlation coefficient with true renal length

  2. Comparative analysis of maximum renal longitudinal length with positional changes on ultrasound with multiplanar reconstructed MR image in Korea Adults

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Yun Hee; Cho, Bum Sang; Kang, Min Ho; Kang, Woo Young; Lee, Jisun; Kim, Yook; Lee, Soo Hyun; Lee, Soo Jung [Dept. of Radiology, Chungbuk National University Hospital, Cheongju (Korea, Republic of); Lee, Jin Yong [Public Health Medical Service, Seoul National University Boramae Medical Center, Seoul (Korea, Republic of)

    2016-07-15

    The purpose of this study was to determine a suitable position in which the measured length on ultrasound is close to the true renal length obtained through a multiplanar reconstructed MR image. A total of 33 individuals (males: 15, females: 18) without any underlying renal disease were included in the present study. Renal length was measured as the longest axis at the level of the renal hilum in three positions-supine, lateral decubitus, and prone, respectively. With a 3.0 T MR scanner, 3D eTHRIVE was acquired. Subsequently, the maximum longitudinal length of both the kidneys was measured through multiplanar reconstructed MR images. Paired t-test was used to compare the renal length obtained from ultrasonographic measurement with the length obtained through multiplanar reconstructed MR images. Our study demonstrated significant difference between sonographic renal length in three positions and renal length through MRI (p < 0.001). However, the longest longitudinal length of right kidney among the measured three values by ultrasound was statistically similar to the renal length measured by reconstructed MR image. Among them, the lateral decubitus position showed the strongest correlation with true renal length (right: 0.887; left: 0.849). We recommend measurement of the maximum renal longitudinal length in all possible positions on ultrasonography. If not allowed, the best measurement is on the lateral decubitus showing the strongest correlation coefficient with true renal length.

  3. Importance of Collateralization in Patients With Large Artery Intracranial Occlusive Disease: Long-Term Longitudinal Assessment of Cerebral Hemodynamic Function

    Directory of Open Access Journals (Sweden)

    Larissa McKetton

    2018-04-01

    Full Text Available Patients with large artery intracranial occlusive disease (LAICOD are at risk for both acute ischemia and chronic hypoperfusion. Collateral circulation plays an important role in prognosis, and imaging plays an essential role in diagnosis, treatment planning, and prognosis of patients with LAICOD. In addition to standard structural imaging, assessment of cerebral hemodynamic function is important to determine the adequacy of collateral supply. Among the currently available methods of assessment of cerebral hemodynamic function, measurement of cerebrovascular reactivity (CVR using blood oxygen level-dependent (BOLD MRI and precisely controlled CO2 has shown to be a safe, reliable, reproducible, and clinically useful method for long-term assessment of patients. Here, we report a case of long-term follow-up in a 28-year-old Caucasian female presented to the neurology clinic with a history of TIAs and LAICOD of the right middle cerebral artery (MCA. Initial structural MRI showed a right MCA stenosis and a small right coronal radiate lacunar infarct. Her CVR study showed a large area of impaired CVR with a paradoxical decrease in BOLD signal with hypercapnia involving the right MCA territory indicating intracerebral steal. The patient was managed medically with anticoagulant and antiplatelet therapy and was followed-up for over 9 years with both structural and functional imaging. Cortical thickness (CT measures were longitudinally assessed from a region of interest that was applied to subsequent time points in the cortical region exhibiting steal physiology and in the same region of the contralateral healthy hemisphere. In the long-term follow-up, the patient exhibited improvement in her CVR as demonstrated by the development of collaterals with negligible changes to CT. Management of patients with LAICOD remains challenging since no revascularization strategies have shown efficacy except in patients with moyamoya disease. Management is well

  4. Longitudinal micro-CT as an outcome measure of interstitial lung disease in TNF-transgenic mice.

    Directory of Open Access Journals (Sweden)

    Richard D Bell

    Full Text Available Rheumatoid arthritis associated interstitial lung disease (RA-ILD is a debilitating condition with poor survival prognosis. High resolution computed tomography (CT is a common clinical tool to diagnose RA-ILD, and is increasingly being adopted in pre-clinical studies. However, murine models recapitulating RA-ILD are lacking, and CT outcomes for inflammatory lung disease have yet to be formally validated. To address this, we validate μCT outcomes for ILD in the tumor necrosis factor transgenic (TNF-Tg mouse model of RA.Cross sectional μCT was performed on cohorts of male TNF-Tg mice and their WT littermates at 3, 4, 5.5 and 12 months of age (n = 4-6. Lung μCT outcomes measures were determined by segmentation of the μCT datasets to generate Aerated and Tissue volumes. After each scan, lungs were obtained for histopathology and 3 sections stained with hematoxylin and eosin. Automated histomorphometry was performed to quantify the tissue area (nuclei, cytoplasm, and extracellular matrix and aerated area (white space within the tissue sections. Spearman's correlation coefficients were used to evaluate the extent of association between μCT imaging and histopathology endpoints.TNF-Tg mice had significantly greater tissue volume, total lung volume and mean intensity at all timepoints compared to age matched WT littermates. Histomorphometry also demonstrated a significant increase in tissue area at 3, 4, and 5.5 months of age in TNF-Tg mice. Lung tissue volume was correlated with lung tissue area (ρ = 0.81, p<0.0001, and normalize lung aerated volume was correlated with normalized lung air area (ρ = 0.73, p<0.0001.We have validated in vivo μCT as a quantitative biomarker of ILD in mice. Further, development of longitudinal measures is critical for dissecting pathologic progression of ILD, and μCT is a useful non-invasive method to study lung inflammation in the TNF-Tg mouse model.

  5. Importance of Collateralization in Patients With Large Artery Intracranial Occlusive Disease: Long-Term Longitudinal Assessment of Cerebral Hemodynamic Function.

    Science.gov (United States)

    McKetton, Larissa; Venkatraghavan, Lakshmikumar; Poublanc, Julien; Sobczyk, Olivia; Crawley, Adrian P; Rosen, Casey; Silver, Frank L; Duffin, James; Fisher, Joseph A; Mikulis, David J

    2018-01-01

    Patients with large artery intracranial occlusive disease (LAICOD) are at risk for both acute ischemia and chronic hypoperfusion. Collateral circulation plays an important role in prognosis, and imaging plays an essential role in diagnosis, treatment planning, and prognosis of patients with LAICOD. In addition to standard structural imaging, assessment of cerebral hemodynamic function is important to determine the adequacy of collateral supply. Among the currently available methods of assessment of cerebral hemodynamic function, measurement of cerebrovascular reactivity (CVR) using blood oxygen level-dependent (BOLD) MRI and precisely controlled CO 2 has shown to be a safe, reliable, reproducible, and clinically useful method for long-term assessment of patients. Here, we report a case of long-term follow-up in a 28-year-old Caucasian female presented to the neurology clinic with a history of TIAs and LAICOD of the right middle cerebral artery (MCA). Initial structural MRI showed a right MCA stenosis and a small right coronal radiate lacunar infarct. Her CVR study showed a large area of impaired CVR with a paradoxical decrease in BOLD signal with hypercapnia involving the right MCA territory indicating intracerebral steal. The patient was managed medically with anticoagulant and antiplatelet therapy and was followed-up for over 9 years with both structural and functional imaging. Cortical thickness (CT) measures were longitudinally assessed from a region of interest that was applied to subsequent time points in the cortical region exhibiting steal physiology and in the same region of the contralateral healthy hemisphere. In the long-term follow-up, the patient exhibited improvement in her CVR as demonstrated by the development of collaterals with negligible changes to CT. Management of patients with LAICOD remains challenging since no revascularization strategies have shown efficacy except in patients with moyamoya disease. Management is well defined for acute

  6. Analysis of the proton longitudinal structure function from the gluon distribution function

    International Nuclear Information System (INIS)

    Boroun, G.R.; Rezaei, B.

    2012-01-01

    We make a critical, next-to-leading order, study of the relationship between the longitudinal structure function F L and the gluon distribution proposed in Cooper-Sarkar et al. (Z. Phys. C 39:281, 1988; Acta Phys. Pol. B 34:2911 2003), which is frequently used to extract the gluon distribution from the proton longitudinal structure function at small x. The gluon density is obtained by expanding at particular choices of the point of expansion and compared with the hard Pomeron behavior for the gluon density. Comparisons with H1 data are made and predictions for the proposed best approach are also provided. (orig.)

  7. A systematic review and meta-analysis on the longitudinal relationship between eating pathology and depression.

    Science.gov (United States)

    Puccio, Francis; Fuller-Tyszkiewicz, Matthew; Ong, Deborah; Krug, Isabel

    2016-05-01

    Undertake a meta-analysis to provide a quantitative synthesis of longitudinal studies that assessed the direction of effects between eating pathology and depression. A second aim was to use meta-regression to account for heterogeneity in terms of study-level effect modifiers. A systematic review was conducted on 42 studies that assessed the longitudinal relationship between eating pathology and depression. Of these 42 studies, multilevel random-effects meta-analyses were conducted on 30 eligible studies. Meta-analysis results showed that eating pathology was a risk factor for depression (rm  = 0.13) and that depression was a risk factor for eating pathology (rm  = 0.16). Meta-regression analyses showed that these effects were significantly stronger for studies that operationalized eating pathology as an eating disorder diagnosis versus eating pathology symptoms, and for studies that operationalized the respective outcome measure as a categorical variable (e.g., a diagnosis of a disorder or where symptoms were "present"/"absent") versus a continuous measure. Results also showed that in relation to eating pathology type, the effect of an eating disorder diagnosis and bulimic symptoms on depression was significantly stronger for younger participants. Eating pathology and depression are concurrent risk factors for each other, suggesting that future research would benefit from identifying factors that are etiological to the development of both constructs. Llevar a cabo un meta-análisis para proporcionar una síntesis cuantitativa de los estudios longitudinales que evaluaron la dirección de los efectos entre la alimentación patológica y la depresión. Un segundo objetivo fue utilizar la meta-regresión para dar cuenta de la heterogeneidad en términos de modificadores del efecto a nivel de estudio. MÉTODO: Una revisión sistemática se llevó a cabo en 42 estudios que evaluaron la relación longitudinal entre la alimentación patológica y la depresión. De

  8. Fetal chromosome analysis: screening for chromosome disease?

    DEFF Research Database (Denmark)

    Philip, J; Tabor, Ann; Bang, J

    1983-01-01

    The aim of the study was to investigate the rationale of the current indications for fetal chromosome analysis. 5372 women had 5423 amniocentesis performed, this group constituting a consecutive sample at the chromosome laboratory, Rigshospitalet, Copenhagen from March 1973 to September 1980 (Group...... A + B). Pregnant women 35 years of age, women who previously had a chromosomally abnormal child, families with translocation carriers or other heritable chromosomal disease, families where the father was 50 years or more and women in families with a history of Down's syndrome (group A), were compared...... to women having amniocentesis, although considered not to have any increased risk of fetal chromosome abnormality (1390 pregnancies, group B). They were also compared with 750 consecutive pregnancies in women 25-34 years of age, in whom all heritable diseases were excluded (group C). The risk of unbalanced...

  9. A comparative analysis of longitudinal computed tomography and histopathology for evaluating the potential of mesenchymal stem cells in mitigating radiation-induced pulmonary fibrosis.

    Science.gov (United States)

    Perez, Jessica R; Lee, Sangkyu; Ybarra, Norma; Maria, Ola; Serban, Monica; Jeyaseelan, Krishinima; Wang, Li Ming; Seuntjens, Jan; Naqa, Issam El

    2017-08-22

    Radiation-induced pulmonary fibrosis (RIPF) is a debilitating side effect that occurs in up to 30% of thoracic irradiations in breast and lung cancer patients. RIPF remains a major limiting factor to dose escalation and an obstacle to applying more promising new treatments for cancer cure. Limited treatment options are available to mitigate RIPF once it occurs, but recently, mesenchymal stem cells (MSCs) and a drug treatment stimulating endogenous stem cells (GM-CSF) have been investigated for their potential in preventing this disease onset. In a pre-clinical rat model, we contrasted the application of longitudinal computed tomography (CT) imaging and classical histopathology to quantify RIPF and to evaluate the potential of MSCs in mitigating RIPF. Our results on histology demonstrate promises when MSCs are injected endotracheally (but not intravenously). While our CT analysis highlights the potential of GM-CSF treatment. Advantages and limitations of both analytical methods are contrasted in the context of RIPF.

  10. Explaining the increasing heritability of cognitive ability across development: a meta-analysis of longitudinal twin and adoption studies.

    Science.gov (United States)

    Briley, Daniel A; Tucker-Drob, Elliot M

    2013-09-01

    Genes account for increasing proportions of variation in cognitive ability across development, but the mechanisms underlying these increases remain unclear. We conducted a meta-analysis of longitudinal behavioral genetic studies spanning infancy to adolescence. We identified relevant data from 16 articles with 11 unique samples containing a total of 11,500 twin and sibling pairs who were all reared together and measured at least twice between the ages of 6 months and 18 years. Longitudinal behavioral genetic models were used to estimate the extent to which early genetic influences on cognition were amplified over time and the extent to which innovative genetic influences arose with time. Results indicated that in early childhood, innovative genetic influences predominate but that innovation quickly diminishes, and amplified influences account for increasing heritability following age 8 years.

  11. Self-control and early adolescent antisocial behavior: A longitudinal analysis

    NARCIS (Netherlands)

    de Kemp, R.A.T.; Vermulst, A.A.; Finkenauer, C.; Scholte, R.H.J.; Overbeek, G.; Rommes, E.W.M.; Engels, R.C.M.E.

    2009-01-01

    The article discusses a three-wave longitudinal study that investigates the relationship between self-control and aggressive and delinquent behavior of early adolescent boys and girls. The sample consists of 1,012 Dutch adolescents (mean age = 12.3) in their first year of secondary education.

  12. A Longitudinal Analysis of Students' Motives for Communicating with Their Instructors

    Science.gov (United States)

    Myers, Scott A.

    2017-01-01

    This study utilized the longitudinal survey research design using students' motives to communicate with their instructors as a test case. Participants were 282 undergraduate students enrolled in introductory communication courses at a large Mid-Atlantic university who completed the Student Communication Motives scale at three points (Time 1:…

  13. Numerical Analysis on Longitudinal Location Optimization of Vortex Generator in Compact Heat Exchangers

    DEFF Research Database (Denmark)

    Gorji, M.; Mirgolbababei, H.; Barari, Amin

    2011-01-01

    In this paper, numerical, curvilinear and turbulent model has been used to investigate the effect of vortex generator's longitudinal displacement on heat transfer and fluid flow in different Reynolds numbers ranging from 500 to 3000. The numerical model has been validated with experimental results...

  14. A 3-year longitudinal analysis of changes in fitness, physical activity, fatness and screen time

    DEFF Research Database (Denmark)

    Aires, L; Andersen, Lars Bo; Mendonça, D

    2010-01-01

    in fitness. METHODS: This is a 3-year longitudinal study of 345 high school students aged 11-19 years. Students performed curl-ups, push-ups and 20-m shuttle run tests from Fitnessgram. PA and ST were evaluated using a standard questionnaire. Standardized scores of fitness tests were summed. Changes over...

  15. A Longitudinal Analysis of Adolescent Decision-Making with the Iowa Gambling Task

    Science.gov (United States)

    Almy, Brandon; Kuskowski, Michael; Malone, Stephen M.; Myers, Evan; Luciana, Monica

    2018-01-01

    Many researchers have used the standard Iowa Gambling Task (IGT) to assess decision-making in adolescence given increased risk-taking during this developmental period. Most studies are cross-sectional and do not observe behavioral trajectories over time, limiting interpretation. This longitudinal study investigated healthy adolescents' and young…

  16. Longitudinal Examination of Optimism, Personal Self-Efficacy and Student Well-Being: A Path Analysis

    Science.gov (United States)

    Phan, Huy P.

    2016-01-01

    The present longitudinal study, based on existing theoretical tenets, explored a conceptual model that depicted four major orientations: optimism, self-efficacy, and academic well-being. An important question for consideration, in this case, involved the testing of different untested trajectories that could explain and predict individuals'…

  17. Maternal Alcohol Consumption During the Perinatal and Early Parenting Period: A Longitudinal Analysis.

    Science.gov (United States)

    Liu, Weiwei; Mumford, Elizabeth A; Petras, Hanno

    2016-02-01

    Despite potential health risks for women and children, one in five women report alcohol use during pregnancy and a significant proportion of those who quit during pregnancy return to drinking post-delivery. This study seeks to understand the longitudinal patterns of alcohol consumption before, during pregnancy and post-delivery, and the role of maternal characteristics for purposes of informing prevention design. General growth mixture models were used to describe the average developmental patterns of maternal weekly drinking quantity at six time points, from preconception through child entering kindergarten, as well as heterogeneity in these patterns among 9100 mothers from the Early Childhood Longitudinal Study representing the 2001 US national birth cohort. Four distinct classes of mothers were defined by their longitudinal alcohol consumption patterns: Low Probability Drinkers (50.3 %), Escalating Risk Drinkers (12.0 %), Escalating Low Risk Drinkers (27.4 %), and Early Parenting Quitters (10.2 %). Heterogeneous covariate associations were observed. For example, mothers who gave birth after age 36 were twice as likely to be Escalating Risk Drinkers and Escalating Low Risk Drinkers (vs Low Probability Drinkers), but not more likely to be Early Parenting Quitters, when compared to mothers who gave birth between the ages of 26 and 35. There is significant heterogeneity in maternal longitudinal alcohol use patterns during the perinatal period. Baseline maternal characteristics and behavior associated with these heterogeneous patterns provide valuable tools to identify potential risky drinkers during this critical time period and may be synthesized to tailor pre- and postnatal clinical counseling protocols.

  18. Temperament, Parenting, and South Korean Early Adolescents' Physical Aggression: A Five-Wave Longitudinal Analysis

    Science.gov (United States)

    Lee, Julie

    2014-01-01

    Objective: This study examined the growth pattern in physical aggression over a five-year period among South Korean early adolescents and the effects of temperament (anger/frustration and emotion regulation) and parenting (harsh parenting and parental monitoring) on early adolescents' physical aggression. Design: A five-year longitudinal design…

  19. Predictors of Changes in Weight Esteem among Mainland Chinese Adolescents: A Longitudinal Analysis

    Science.gov (United States)

    Chen, Hong; Jackson, Todd

    2009-01-01

    Weight and body image concerns are prevalent among adolescents across cultures and pose significant threats to well-being, yet there is a paucity of longitudinal research on samples living in non-Western and developing countries. This prospective study assessed the extent to which select sociocultural, psychological, and biological risk factors…

  20. The Use of Longitudinal Analysis to Identify More and Less Effective Schools.

    Science.gov (United States)

    Goldberg, Zandra S.; Spartz, James L.

    Three longitudinal studies of student achievement test data were conducted to examine the extent to which the variation in student achievement can be explained by differences in student background (including socioeconomic and prior achievement data) and school resources. This model assumes that achievement test performance may be predicted by…

  1. Forms and Functions of Aggression in Adolescent Friendship Selection and Influence : A Longitudinal Social Network Analysis

    NARCIS (Netherlands)

    Sijtsema, Jelle J.; Ojanen, Tiina; Veenstra, Rene; Lindenberg, Siegwart; Hawley, Patricia H.; Little, Todd D.

    Aggressive children are known to have friends. However, less is known about the impact of aggression on friendship development and how this can differ for overt and relational (i.e., the forms) and instrumental and reactive (i.e., the functions) aggression. This longitudinal study utilized the forms

  2. Quality of life in patients with depression, panic syndrome, other anxiety syndrome, alcoholism and chronic somatic diseases: a longitudinal study in Slovenian primary care patients.

    Science.gov (United States)

    Cerne, Anja; Rifel, Janez; Rotar-Pavlic, Danica; Svab, Igor; Selic, Polona; Kersnik, Janko

    2013-01-01

    To analyse the correlates between the quality of life and chronic diseases and socio-demographic characteristics of patients in family medicine with a special emphasis on depression, panic syndrome, other anxiety syndrome and alcoholism. In a longitudinal study, the data set of 516 family practice attendees recruited from 60 family practices was analysed. Depression, panic syndrome, other anxiety syndrome and alcoholism were diagnosed using appropriate diagnostic interviews. Quality of life was assessed using the SF-12 questionnaire, measuring a mental health score and a physical health score. Data about the number of chronic somatic diseases were obtained from the patients' medical records. Physical health score was negatively associated with higher age (β = -0.25, p chronic somatic diseases (β = -0.10, p chronic somatic diseases as they are associated with poorer quality of life.

  3. Stream gradient Hotspot and Cluster Analysis (SL-HCA) for improving the longitudinal profiles metrics

    Science.gov (United States)

    Troiani, Francesco; Piacentini, Daniela; Seta Marta, Della

    2016-04-01

    Many researches successfully focused on stream longitudinal profiles analysis through Stream Length-gradient (SL) index for detecting, at different spatial scales, either tectonic structures or hillslope processes. The analysis and interpretation of spatial variability of SL values, both at a regional and local scale, is often complicated due to the concomitance of different factors generating SL anomalies, including the bedrock composition. The creation of lithologically-filtered SL maps is often problematic in areas where homogeneously surveyed geological maps, with a sufficient resolution are unavailable. Moreover, both the SL map classification and the unbiased anomaly detection are rather difficult. For instance, which is the best threshold to define the anomalous SL values? Further, is there a minimum along-channel extent of anomalous SL values for objectively defining over-steeped segments on long-profiles? This research investigates the relevance and potential of a new approach based on Hotspot and Cluster Analysis of SL values (SL-HCA) for detecting knickzones on long-profiles at a regional scale and for fine-tuning the interpretation of their geological-geomorphological meaning. We developed this procedure within a 2800 km2-wide area located in the mountainous sector of the Northern Apennines of Italy. The Getis-Ord Gi∗ statistic is applied for the SL-HCA approach. The value of SL, calculated starting from a 5x5 m Digital Elevation Model, is used as weighting factor and the Gi∗ index is calculated for each 50 m-long channel segment for the whole fluvial system. The outcomes indicate that high positive Gi∗ values imply the clustering of SL anomalies, thus the occurrence of knickzones on the stream long-profiles. Results show that high and very high Gi* values (i.e. values beyond two standard deviations from the mean) correlate well with the principal knickzones detected with existent lithologically-filtered SL maps. Field checks and remote sensing

  4. Nutritional status, cachexia, and anorexia in women with peritoneal metastasis and intraperitoneal chemotherapy: a longitudinal analysis.

    Science.gov (United States)

    Hilal, Ziad; Rezniczek, Günther A; Klenke, Robert; Dogan, Askin; Tempfer, Clemens B

    2017-11-01

    To describe the nutritional status of women with peritoneal metastasis (PM) from recurrent ovarian, fallopian, or peritoneal cancer and to assess longitudinal variations of the cachexia-anorexia syndrome (CAS) during palliative pressurized intraperitoneal aerosol chemotherapy (PIPAC). Nutritional assessment included body mass index (BMI), bioelectrical impedance analysis (BIA), and blood chemistry. CAS presence/absence was recorded before and during repeated cycles (1-11) of PIPAC. Eighty-four patients with peritoneal cancer (n=5) or PM from recurrent ovarian (n=77) or fallopian tube (n=2) cancer were included. At baseline, resting metabolism (RM) (1,432±172 kcal/day), visceral fat level (7.5±3.2), skeletal muscle mass (27.2%±4.6%), upper arm circumference (27.9±4.6 cm), lower leg circumference (35.1±3.9 cm), serum parameters (albumin [3.5±0.7 g/dL], total protein [6.3±0.9 g/dL], and transferrin [202±60 mg/dL]) were below normal limits. C-reactive protein (CRP) (4.3±6.8 mg/dL), caliper body fat (35.7%±6.3%), and total body fat mass (35.6%±8.5%) were above normal limits. Nineteen/84 (23%) patients had CAS at baseline. Deterioration or stabilization/improvement of CAS was observed in 9/55 (16.4%) and 46/55 (83.6%) patients with follow-up data, respectively. Baseline body fat mass, visceral fat level, skeletal muscle mass, caliper body fat, BMI, ascites, Karnofsky index, RM, and CRP, as well as tumor response were not predictive of CAS deterioration. Nutritional decline and onset or deterioration of CAS are difficult to predict. Careful measuring and monitoring of nutritional parameters and CAS in all patients seems to be necessary in order to identify those patients in need of enteral/parenteral nutrition support. Copyright © 2017. Asian Society of Gynecologic Oncology, Korean Society of Gynecologic Oncology

  5. Analysis of Medical Tourism for Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Catalina Liliana Andrei

    2014-11-01

    Full Text Available Increasing costs of treatments have led to the apparition of the medical tourism. Patients in high-income countries seek to solve their health problems in developing countries where the cost of medical treatment is much lower. This cost difference has led to the medical tourism industry that is currently estimated with an annual growth rate of about 20%. Cardiovascular diseases are a leading cause of death worldwide. The high cost of treating these diseases cause many patients to seek treatment options abroad. This paper presents an analysis of the medical tourism industry highlighting the factors that led to its development, barriers to medical tourism, and the economic impact of this industry. Although Romania has highly appreciated doctors it hasn’t achieved yet the high level of other developing countries where medical tourism is more intense. Spa tourism is still far from Romania’s potential in this area due to the very small investments and the lack of necessary infrastructure. Using statistical and econometric techniques we examined key health indicators in Romania showing the lack of correlation between the prevalence of cardiovascular diseases, the development of the endowment of the health system in Romania, expenditures on health care and evolution of the number of foreign tourists coming to Romania to treat these diseases. We used statistical data series provided by N.S.I. that were processed using Eviews. We also tested whether there is a causal relationship in the Granger sense between the percentage of GDP allocated to the health care system and the number of nights spent by foreign tourists in resorts in Romania or the number of arrivals of foreign tourists.

  6. Disease management programs for patients with type 2 diabetes mellitus in Germany: a longitudinal population-based descriptive study.

    Science.gov (United States)

    Mehring, Michael; Donnachie, Ewan; Bonke, Florian Cornelius; Werner, Christoph; Schneider, Antonius

    2017-01-01

    The primary aim of the disease management program (DMP) for patients with diabetes mellitus type 2 is to improve the quality of health care and the treatment process. 12 years after its introduction in Germany, there is still no consensus as to whether DMP has been effective in reaching these goals. A retrospective longitudinal population-based study between 2004 and 2015 were conducted to evaluate the DMP for type 2 diabetes in Bavaria using routinely collected patient medical records hold from the National Association of Statutory Health Insurance Physicians of Bavaria. During the first 12 years of DMP, the number of participants increased continually to reach 580,222 in 2015. The proportion of participants older than 70 years increased during the observation from 41.6 to 51.1%. The percentage of smokers increased slightly from 9 to 11%. Similarly, the distribution of body mass index remained constant with approximately 50% of patients having a body mass index >30 kg/m 2 . Control of HbA1c was without an appreciable change over the course, with between 8.3 and 9.4% of all patients with uncontrolled values higher than 8.5%. Prescription of metformin increased from 40.5% in 2004 to 54.1% in 2015. Among patients receiving insulin, the proportion receiving a combined therapy with metformin increased from 28.4% in 2004 to 50.8% in 2015. In contrast, the percentage with insulin monotherapy decreased from 55.4 to 33.7%. The proportion of patients with a diabetic education increased within the course from 12.8 to 29.3%. Data from the German DMP for type 2 diabetes demonstrates an improvement in the quality of care with respect to pharmacotherapy and patient education and therefore to an improved adherence to guidelines. However, no appreciable improvement was observed with regard to smoking status, obesity or HbA1c control.

  7. Internet Searching About Disease Elicits a Positive Perception of Own Health When Severity of Illness Is High: A Longitudinal Questionnaire Study.

    Science.gov (United States)

    Sassenberg, Kai; Greving, Hannah

    2016-03-04

    The Internet is one of the primary sources for health information. However, in research, the effects of Internet use on the perception of one's own health have not received much attention so far. This study tested how Internet use for acquiring health information and severity of illness influence patients with a chronic disease with regard to the perception of their own health. Negative psychological states are known to lead to preferential processing of positive information. In particular, the self-directed nature of Internet use provides room for such biases. Therefore, we predicted that patients experiencing negative health states more frequently, due to more frequent episodes of a chronic illness, will gain a more positive perception of their health if they use the Internet frequently to gain health information, but not if they use the Internet rarely. This effect was not expected for other sources of information. A longitudinal questionnaire study with two measurement points-with a 7-month time lag-tested the hypothesis in a sample of patients with chronic inflammatory bowel disease (n=208). This study assessed patients' frequency of Internet use, their participation in online social support groups, their use of other sources of health information, and several indicators of the participants' perceptions of their own health. A structure equation model (SEM) was used to test the predictions separately for Internet searches and other sources of information. Data analysis supported the prediction; the interaction between frequency of health-related information searches and frequency of episodes at the first measurement point (T1) was related to participants' positive perceptions of their own health at the second measurement point (T2) (B=.10, SE=.04, P=.02) above and beyond the perceptions of their own health at T1. When participants used the Internet relatively rarely (-1 SD), there was no relationship between frequency of episodes and positive perceptions of

  8. Enabling Analysis of Big, Thick, Long, and Wide Data: Data Management for the Analysis of a Large Longitudinal and Cross-National Narrative Data Set.

    Science.gov (United States)

    Winskell, Kate; Singleton, Robyn; Sabben, Gaelle

    2018-03-01

    Distinctive longitudinal narrative data, collected during a critical 18-year period in the history of the HIV epidemic, offer a unique opportunity to examine how young Africans are making sense of evolving developments in HIV prevention and treatment. More than 200,000 young people from across sub-Saharan Africa took part in HIV-themed scriptwriting contests held at eight discrete time points between 1997 and 2014, creating more than 75,000 narratives. This article describes the data reduction and management strategies developed for our cross-national and longitudinal study of these qualitative data. The study aims to inform HIV communication practice by identifying cultural meanings and contextual factors that inform sexual behaviors and social practices, and also to help increase understanding of processes of sociocultural change. We describe our sampling strategies and our triangulating methodologies, combining in-depth narrative analysis, thematic qualitative analysis, and quantitative analysis, which are designed to enable systematic comparison without sacrificing ethnographic richness.

  9. The risk of falling into poverty after developing heart disease: a survival analysis.

    Science.gov (United States)

    Callander, Emily J; Schofield, Deborah J

    2016-07-15

    Those with a low income are known to have a higher risk of developing heart disease. However, the inverse relationship - falling into income poverty after developing heart disease has not been explored with longitudinal data. This paper aims to determine if those with heart disease have an elevated risk of falling into poverty. Survival analysis was conducted using the longitudinal Household Income and Labour Dynamics in Australia survey, between the years 2007 and 2012. The study focused on the Australian population aged 21 years and over in 2007 who were not already in poverty and did not already have heart disease, who were followed from 2007 to 2012. Cox regression models adjusting for age, sex and time-varying co-variates (marital status, home ownership and remoteness of area of residence) were constructed to assess the risk of falling into poverty. For those aged 20 who developed heart disease, the hazard ratio for falling into income poverty was 9.24 (95 % CI: 8.97-9.51) and for falling into multidimensional poverty the hazard ratio was 14.21 (95 % CI: 13.76-14.68); for those aged 40 the hazard ratio for falling into income poverty was 3.45 (95 % CI: 3.39-3.51) and for multidimensional poverty, 5.20 (95 % CI: 5.11-5.29); and for those aged 60 the hazard ratio for falling into income poverty was 1.29 (95 % CI: 1.28-1.30) and for multidimensional poverty, 1.52 (95 % CI: 1.51-1.54), relative those who never developed heart disease. The risk for both income and multidimensional poverty decreases with age up to the age of 70, over which, those who developed heart disease had a reduced risk of poverty. For those under the age of 70, developing heart disease is associated with an increased risk of falling into both income poverty and multidimensional poverty.

  10. The effects of workplace flexibility on health behaviors: a cross-sectional and longitudinal analysis.

    Science.gov (United States)

    Grzywacz, Joseph G; Casey, Patrick R; Jones, Fiona A

    2007-12-01

    To examine the cross-sectional and longitudinal associations between workplace flexibility and health behaviors, and estimate the potential importance of flexibility for effective worksite health promotion programs. Cross-sectional and longitudinal health risk appraisal data were obtained from US based employees of a multinational pharmaceutical company (n = 3193). Examined health behaviors were hours of sleep, physical activity frequency, health education seminar attendance, frequency of practicing personal resilience techniques, and self-appraised lifestyle. Self-reported flexibility in the workplace was the primary independent variable. Each health behavior, except regular attendance in health education seminars, was positively related to perceived flexibility in cross-sectional analyses. Sleep and self-appraised lifestyle were significantly related to changes in perceived flexibility over time. Workplace flexibility may contribute to positive lifestyle behaviors, and may play an important role in effective worksite health promotion programs.

  11. Maternal patterns of postpartum alcohol consumption by age: A longitudinal analysis of adult urban mothers

    OpenAIRE

    Liu, Weiwei; Mumford, Elizabeth A.; Petras, Hanno

    2015-01-01

    The purpose of this study is to investigate a) longitudinal patterns of maternal postpartum alcohol use as well as its variation by maternal age at child birth; b) within maternal age groups, the association between other maternal characteristics and alcohol use patterns for the purposes of informed prevention design. Study sample consists of 3,397 mothers from the Fragile Families and Child Wellbeing Study representing medium and large U.S. urban areas. Maternal drinking and binge drinking w...

  12. Fracture mechanics analysis of a longitudinally cracked bend under cyclic loading

    International Nuclear Information System (INIS)

    Kussmaul, K.; Uhlmann, D.; Koski, K.; Hunger, H.

    1993-01-01

    Where information is available about the actual crack configuration, the boundary conditions of the load case, the geometry, and the material characteristics, extensive numerical calculations by means of the finite element method allow crack growth to be calculated for pipe bends carrying longitudinal cracks. If the influence of multiple-crack fields is taken into account in the crack growth calculations, good agreement is obtained with experimental findings. Less sophisticated assessments of individual cracks furnish results which are on the safe side. (author)

  13. Longitudinal analysis of music education on executive functions in primary school children

    OpenAIRE

    Jaschke, A.C.; Honing, H.; Scherder, E.J.A.

    2018-01-01

    Background: Research on the effects of music education on cognitive abilities has generated increasing interest across the scientific community. Nonetheless, longitudinal studies investigating the effects of structured music education on cognitive sub-functions are still rare. Prime candidates for investigating a relationship between academic achievement and music education appear to be executive functions such as planning, working memory, and inhibition. Methods: One hundred and forty-seven ...

  14. Longitudinal Analysis of Music Education on Executive Functions in Primary School Children

    OpenAIRE

    Artur C. Jaschke; Artur C. Jaschke; Henkjan Honing; Erik J. A. Scherder

    2018-01-01

    Background: Research on the effects of music education on cognitive abilities has generated increasing interest across the scientific community. Nonetheless, longitudinal studies investigating the effects of structured music education on cognitive sub-functions are still rare. Prime candidates for investigating a relationship between academic achievement and music education appear to be executive functions such as planning, working memory, and inhibition.Methods: One hundred and forty-seven p...

  15. Cluster emergence and network evolution A longitudinal analysis of the inventor network in Sophia-Antipolis

    OpenAIRE

    Anne L. J. ter Wal

    2008-01-01

    Abstract It is increasingly acknowledged that clusters do not necessarily exhibit networks of local collective learning. This paper addresses the question under which conditions this is the case. Through a longitudinal case study of the business park Sophia-Antipolis it investigates how networks of collective learning emerged throughout the growth of the cluster. Network reconstruction with patent data shows that an innovation network emerged only in Information Technology, in whic...

  16. Development of sedentary behavior across childhood and adolescence: longitudinal analysis of the Gateshead Millennium Study

    OpenAIRE

    Janssen, Xanne; Mann, Kay D.; Basterfield, Laura; Parkinson, Kathryn N.; Pearce, Mark S.; Reilly, Jessica K.; Adamson, Ashley J.; Reilly, John J.

    2016-01-01

    Background In many parts of the world policy and research interventions to modify sedentary behavior of children and adolescents are now being developed. However, the evidence to inform these interventions (e.g. how sedentary behavior changes across childhood and adolescence) is limited. This study aimed to assess longitudinal changes in sedentary behavior, and examine the degree of tracking of sedentary behavior from age 7y to 15y. Methods Participants were part of the Gateshead Millennium S...

  17. Predicting Children's Media Use in the USA: Differences in Cross-Sectional and Longitudinal Analysis

    Science.gov (United States)

    Lee, Sook-Jung; Bartolic, Silvia; Vandewater, Elizabeth A.

    2009-01-01

    The purpose of this paper is to examine the predictors of children's media use in the USA, comparing cross-sectional and longitudinal analyses. Data come from Waves 1 and 2 of the Child Development Supplement (CDS-I; CDS-II), a nationally representative sample of American children aged 0-12 in 1997 and 5-18 in 2002. Twenty-four hour time use…

  18. The Relationship Between Job Satisfaction and Productivity-Related Costs: A Longitudinal Analysis.

    Science.gov (United States)

    Arnold, Amélie E; Coffeng, Jennifer K; Boot, Cécile R L; van der Beek, Allard J; van Tulder, Maurits W; Nieboer, Dagmar; van Dongen, Johanna M

    2016-09-01

    The aim of this study was to examine the longitudinal relationship between job satisfaction and total productivity-related costs, and between job satisfaction and absenteeism and presenteeism costs separately. A secondary aim was to explore whether these relationships differed across job types. Linear generalized estimating equation analyses were used to explore the longitudinal relationships. To explore whether the relationships differed across job types, stratified analyses were performed. A significant relationship was found between job satisfaction and total productivity-related costs [β = &OV0556;-273; 95% confidence interval (95% CI): -407 to -200] and between job satisfaction and presenteeism costs (β = &OV0556;-276; 95% CI: -367 to -235), but not between job satisfaction and absenteeism costs. These relationships differed across job types. Higher levels of job satisfaction were longitudinally related to lower total productivity-related costs and presenteeism costs, but not to lower absenteeism costs. These relationships seem to differ across job types.

  19. A Longitudinal Analysis of the Influence of a Peer Run Warm Line Phone Service on Psychiatric Recovery.

    Science.gov (United States)

    Dalgin, Rebecca Spirito; Dalgin, M Halim; Metzger, Scott J

    2018-05-01

    This article focuses on the impact of a peer run warm line as part of the psychiatric recovery process. It utilized data including the Recovery Assessment Scale, community integration measures and crisis service usage. Longitudinal statistical analysis was completed on 48 sets of data from 2011, 2012, and 2013. Although no statistically significant differences were observed for the RAS score, community integration data showed increases in visits to primary care doctors, leisure/recreation activities and socialization with others. This study highlights the complexity of psychiatric recovery and that nonclinical peer services like peer run warm lines may be critical to the process.

  20. Analysis of the Mechanism of Longitudinal Bending Deformation Due to Welding in a Steel Plate by Using a Numerical Model

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Rae; Yan, Jieshen; Kim, Jae-Woong [Yeungnam Univ., Gyeongsan (Korea, Republic of); Song, Gyu Yeong [Gyeongbuk Hybrid Technology Institute, Yeongcheon (Korea, Republic of)

    2017-01-15

    Welding deformation is a permanent deformation that is caused in structures by welding heat. Welding distortion is the primary cause of reduced productivity, due to welded structural strength degradation, low dimensional accuracy, and appearance. As a result, research and numerous experiments are being carried out to control welding deformation. The aim of this study is to analyze the mechanism of longitudinal bending deformation due to welding. Welding experiments and numerical analyses were performed for this study. The welding experiments were performed on 4 mm and 8.5 mm thickness steel plates, and the numerical analysis was conducted on the welding deformation using the FE software MSC.marc.

  1. Haplotype-based association analysis of general cognitive ability in Generation Scotland, the English Longitudinal Study of Ageing, and UK Biobank [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    David M. Howard

    2017-08-01

    Full Text Available Background: Cognitive ability is a heritable trait with a polygenic architecture, for which several associated variants have been identified using genotype-based and candidate gene approaches. Haplotype-based analyses are a complementary technique that take phased genotype data into account, and potentially provide greater statistical power to detect lower frequency variants. Methods: In the present analysis, three cohort studies (ntotal = 48,002 were utilised: Generation Scotland: Scottish Family Health Study (GS:SFHS, the English Longitudinal Study of Ageing (ELSA, and the UK Biobank. A genome-wide haplotype-based meta-analysis of cognitive ability was performed, as well as a targeted meta-analysis of several gene coding regions. Results: None of the assessed haplotypes provided evidence of a statistically significant association with cognitive ability in either the individual cohorts or the meta-analysis. Within the meta-analysis, the haplotype with the lowest observed P-value overlapped with the D-amino acid oxidase activator (DAOA gene coding region. This coding region has previously been associated with bipolar disorder, schizophrenia and Alzheimer’s disease, which have all been shown to impact upon cognitive ability. Another potentially interesting region highlighted within the current genome-wide association analysis (GS:SFHS: P = 4.09 x 10-7, was the butyrylcholinesterase (BCHE gene coding region. The protein encoded by BCHE has been shown to influence the progression of Alzheimer’s disease and its role in cognitive ability merits further investigation. Conclusions: Although no evidence was found for any haplotypes with a statistically significant association with cognitive ability, our results did provide further evidence that the genetic variants contributing to the variance of cognitive ability are likely to be of small effect.

  2. A longitudinal analysis of arterial dopler parameters in growth restricted fetuses

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    Miković Željko

    2003-01-01

    Full Text Available Doppler parameters enable noninvasive and direct detection of placental insufficiency and brain sparing effect, which occurs as an adaptive mechanism to chronic hypoxemia. It is of great interest if further changes of Doppler parameters, which occur after the detection of the first pathologic value, can anticipate a moment of fetal distress. We investigated growth-restricted fetuses with the brain sparing effect in the time interval between the detection of blood flow redistribution until the distress. The aim of our study was to evaluate longitudinally Doppler parameters in umbilical (Aum, medial cerebral (MCA, renal (AR and femoral (AF artery and find: 1 if there are significant changes in their value; 2 the character and time interval of these changes; and 3 if they differ from changes in biophysical profile (BFP. MATERIALS AND METHODS Prospective clinical study evaluated 35 pregnancies with fetal growth restriction. Fetuses were selected for the study if: 1 there were pathologic cerebral/umbilical (C/U ratio, 2 at least four Doppler examinations in 3-4 days interval were performed and 3 prepartal fetal distress, defined as silent fetal heart rate pattern with spontaneous and late decelerations, was present. In 28 neonates after delivery umbilical artery gas and acid-base status was determined. Blood flow velocity waveforms were evaluated in Aum MCA, AR, and AF. Arterial blood flow was estimated by pulsatility index (Pi, while in Aum we also used: present end-diastolic velocity (PEDV absent end-diastolic velocity (AEDV and reverse end-diastolic velocity (REDV. All of the fetuses were monitored by cardiotocogram (CTG once to twice a day and by BFP twice a week. Elective Cesarean section was done in the presence of distress, except if severe immaturity or extreme malnutrition occurred. RESULTS Etiological factors of placental insufficiency were: 1 hypertensive syndrome (n=26, 2 chronic renal disease (n=3, 3 primary antiphospholipid syndrome (n

  3. Factors of risk and protection/resilience in adolescent scholar bullying. Longitudinal analysis

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    Hernández de Frutos, Teodoro

    2014-12-01

    Full Text Available Theories of risk, protection and resilience have gained widespread acceptance in recent years, as the university community, to a large extent, consider that they offer a satisfactory explanation as to why some adolescents fail to survive in a hostile environment while others cope adequately, almost as if they were immunized against the difficulties they encounter in the course of their lives. Applying these theories to adolescent harassment could explain why certain youth fall victim to it and others do not, despite sharing the same life variables: age, sex, school structure, family structure, residential area, mass media and so on. This longitudinal analysis examines the risks and resilience associated with the social environment, using Bronfenbrenner’s version, taking into account that resilience is not necessarily due to individual personality conditioning or other significant factors, as some theories hold. Rather, it argues that environmental factors may also be responsible for increasing or reducing its effects. Given that some experts use this concept in a manner that leads to confusion, understanding adolescent bullying to be aggressive behavior on an individual level, it is necessary to highlight that it is understood here to be a multidimensional concept. It is a single variable which includes individual aggression, collective aggression, individual and collective victimization. This will avoid the misunderstanding arising from a holistic and undifferentiated use of the term. It also takes into account that the aggressor as well as the victim is also exposed, although to a lesser degree, to risks, protection and resilience.Las teorías del riesgo, protección/resiliencia han surgido con fuerza en los últimos años porque explican satisfactoriamente, en opinión de una por parte significativa de la comunidad universitaria, porque algunos adolescentes se hunden en un medio ambiente hostil, mientras que otros sobreviven sin que parezca

  4. Longitudinal control behaviour: Analysis and modelling based on experimental surveys in Italy and the UK.

    Science.gov (United States)

    Pariota, Luigi; Bifulco, Gennaro Nicola; Galante, Francesco; Montella, Alfonso; Brackstone, Mark

    2016-04-01

    This paper analyses driving behaviour in car-following conditions, based on extensive individual vehicle data collected during experimental field surveys carried out in Italy and the UK. The aim is to contribute to identify simple evidence to be exploited in the ongoing process of driving assistance and automation which, in turn, would reduce rear-end crashes. In particular, identification of differences and similarities in observed car-following behaviours for different samples of drivers could justify common tuning, at a European or worldwide level, of a technological solution aimed at active safety, or, in the event of differences, could suggest the most critical aspects to be taken into account for localisation or customisation of driving assistance solutions. Without intending to be exhaustive, this paper moves one step in this direction. Indeed, driving behaviour and human errors are considered to be among the main crash contributory factors, and a promising approach for safety improvement is the progressive introduction of increasing levels of driving automation in next-generation vehicles, according to the active/preventive safety approach. However, the more advanced the system, the more complex will be the integration in the vehicle, and the interaction with the driver may sometimes become unproductive, or risky, should the driver be removed from the driving control loop. Thus, implementation of these systems will require the interaction of human driving logics with automation logics and then an enhanced ability in modelling drivers' behaviour. This will allow both higher active-safety levels and higher user acceptance to be achieved, thus ensuring that the driver is always in the control loop, even if his/her role is limited to supervising the automatic logic. Currently, the driving mode most targeted by driving assistance systems is longitudinal driving. This is required in various driving conditions, among which car-following assumes key importance

  5. Statistical analysis of entropy generation in longitudinally finned tube heat exchanger with shell side nanofluid by a single phase approach

    Directory of Open Access Journals (Sweden)

    Konchada Pavan Kumar

    2016-06-01

    Full Text Available The presence of nanoparticles in heat exchangers ascertained increment in heat transfer. The present work focuses on heat transfer in a longitudinal finned tube heat exchanger. Experimentation is done on longitudinal finned tube heat exchanger with pure water as working fluid and the outcome is compared numerically using computational fluid dynamics (CFD package based on finite volume method for different flow rates. Further 0.8% volume fraction of aluminum oxide (Al2O3 nanofluid is considered on shell side. The simulated nanofluid analysis has been carried out using single phase approach in CFD by updating the user-defined functions and expressions with thermophysical properties of the selected nanofluid. These results are thereafter compared against the results obtained for pure water as shell side fluid. Entropy generated due to heat transfer and fluid flow is calculated for the nanofluid. Analysis of entropy generation is carried out using the Taguchi technique. Analysis of variance (ANOVA results show that the inlet temperature on shell side has more pronounced effect on entropy generation.

  6. Longitudinal burnout-collaboration patterns in Japanese medical care workers at special needs schools: a latent class growth analysis

    Directory of Open Access Journals (Sweden)

    Kanayama M

    2016-06-01

    Full Text Available Mieko Kanayama,1 Machiko Suzuki,1 Yoshikazu Yuma2 1Department of Human Health Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan; 2Department of Human Development Education, Graduate School of Education, Hyogo University of Teacher Education, Kato, Hyogo, Japan Abstract: The present study aimed to identify and characterize potential burnout types and the relationship between burnout and collaboration over time. Latent class growth analysis and the growth mixture model were used to identify and characterize heterogeneous patterns of longitudinal stability and change in burnout, and the relationship between burnout and collaboration. We collected longitudinal data at three time points based on Japanese academic terms. The 396 study participants included academic teachers, yogo teachers, and registered nurses in Japanese special needs schools. The best model included four types of both burnout and collaboration in latent class growth analysis with intercept, slope, and quadratic terms. The four types of burnout were as follows: low stable, moderate unstable, high unstable, and high decreasing. They were identified as involving inverse collaboration function. The results indicated that there could be dynamic burnout types, namely moderate unstable, high unstable, and high decreasing, when focusing on growth trajectories in latent class analyses. The finding that collaboration was dynamic for dynamic burnout types and stable for stable burnout types is of great interest. This was probably related to the inverse relationship between the two constructs. Keywords: burnout, collaboration, latent class growth analysis, interprofessional care, special needs schools

  7. Quantitative longitudinal interrelationships between brain metabolism and amyloid deposition during a 2-year follow-up in patients with early Alzheimer's disease

    International Nuclear Information System (INIS)

    Foerster, Stefan; Yousefi, Behrooz H.; Wester, Hans-Juergen; Klupp, Elisabeth; Rominger, Axel; Foerstl, Hans; Kurz, Alexander; Grimmer, Timo; Drzezga, Alexander

    2012-01-01

    Similar regional anatomical distributions were reported for fibrillary amyloid deposition [measured by 11 C-Pittsburgh compound B (PIB) positron emission tomography (PET)] and brain hypometabolism [measured by 18 F-fluorodeoxyglucose (FDG) PET] in numerous Alzheimer's disease (AD) studies. However, there is a lack of longitudinal studies evaluating the interrelationships of these two different pathological markers in the same AD population. Our most recent AD study suggested that the longitudinal pattern of hypometabolism anatomically follows the pattern of amyloid deposition with temporal delay, which indicates that neuronal dysfunction may spread within the anatomical pattern of amyloid pathology. Based on this finding we now hypothesize that in early AD patients quantitative longitudinal decline in hypometabolism may be related to the amount of baseline amyloid deposition during a follow-up period of 2 years. Fifteen patients with mild probable AD underwent baseline (T1) and follow-up (T2) examination after 24 ± 2.1 months with [ 18 F]FDG PET, [ 11 C]PIB PET, structural T1-weighted MRI and neuropsychological testing [Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological battery]. Longitudinal cognitive measures and quantitative PET measures of amyloid deposition and metabolism [standardized uptake value ratios (SUVRs)] were obtained using volume of interest (VOI)-based approaches in the frontal-lateral-retrosplenial (FLR) network and in predefined bihemispheric brain regions after partial volume effect (PVE) correction of PET data. Statistical group comparisons (SUVRs and cognitive measures) between patients and 15 well-matched elderly controls who had undergone identical imaging procedures once as well as Pearson's correlation analyses within patients were performed. Group comparison revealed significant cognitive decline and increased mean PIB/decreased FDG SUVRs in the FLR network as well as in several AD-typical regions in

  8. Quantitative longitudinal interrelationships between brain metabolism and amyloid deposition during a 2-year follow-up in patients with early Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Foerster, Stefan [Technische Universitaet Muenchen, Department of Nuclear Medicine, Munich (Germany); Technische Universitaet Muenchen, TUM-Neuroimaging Center (TUM-NIC), Munich (Germany); Technische Universitaet Muenchen (TUM), Klinik und Poliklinik fuer Nuklearmedizin, Klinikum rechts der Isar, Munich (Germany); Yousefi, Behrooz H.; Wester, Hans-Juergen; Klupp, Elisabeth [Technische Universitaet Muenchen, Department of Nuclear Medicine, Munich (Germany); Rominger, Axel [Ludwig Maximilians Universitaet Muenchen, Department of Nuclear Medicine, Munich (Germany); Foerstl, Hans; Kurz, Alexander; Grimmer, Timo [Technische Universitaet Muenchen, Department of Psychiatry and Psychotherapy, Munich (Germany); Drzezga, Alexander [Technische Universitaet Muenchen, Department of Nuclear Medicine, Munich (Germany); Technische Universitaet Muenchen, TUM-Neuroimaging Center (TUM-NIC), Munich (Germany)

    2012-12-15

    Similar regional anatomical distributions were reported for fibrillary amyloid deposition [measured by {sup 11}C-Pittsburgh compound B (PIB) positron emission tomography (PET)] and brain hypometabolism [measured by {sup 18}F-fluorodeoxyglucose (FDG) PET] in numerous Alzheimer's disease (AD) studies. However, there is a lack of longitudinal studies evaluating the interrelationships of these two different pathological markers in the same AD population. Our most recent AD study suggested that the longitudinal pattern of hypometabolism anatomically follows the pattern of amyloid deposition with temporal delay, which indicates that neuronal dysfunction may spread within the anatomical pattern of amyloid pathology. Based on this finding we now hypothesize that in early AD patients quantitative longitudinal decline in hypometabolism may be related to the amount of baseline amyloid deposition during a follow-up period of 2 years. Fifteen patients with mild probable AD underwent baseline (T1) and follow-up (T2) examination after 24 {+-} 2.1 months with [{sup 18}F]FDG PET, [{sup 11}C]PIB PET, structural T1-weighted MRI and neuropsychological testing [Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological battery]. Longitudinal cognitive measures and quantitative PET measures of amyloid deposition and metabolism [standardized uptake value ratios (SUVRs)] were obtained using volume of interest (VOI)-based approaches in the frontal-lateral-retrosplenial (FLR) network and in predefined bihemispheric brain regions after partial volume effect (PVE) correction of PET data. Statistical group comparisons (SUVRs and cognitive measures) between patients and 15 well-matched elderly controls who had undergone identical imaging procedures once as well as Pearson's correlation analyses within patients were performed. Group comparison revealed significant cognitive decline and increased mean PIB/decreased FDG SUVRs in the FLR network as well as

  9. Mortality among immigrants in England and Wales by major causes of death, 1971-2012: A longitudinal analysis of register-based data.

    Science.gov (United States)

    Wallace, Matthew; Kulu, Hill

    2015-12-01

    Recent research has found a migrant mortality advantage among immigrants relative to the UK-born population living in England and Wales. However, while all-cause mortality is useful to show differences in mortality between immigrants and the host population, it can mask variation in mortality patterns from specific causes of death. This study analyses differences in the causes of death among immigrants living in England and Wales. We extend previous research by applying competing-risks survival analysis to study a large-scale longitudinal dataset from 1971 to 2012 to directly compare causes of death. We confirm low all-cause mortality among nearly all immigrants, except immigrants from Scotland, Northern Ireland and the Republic of Ireland (who have high mortality). In most cases, low all-cause mortality among immigrants is driven by lower mortality from chronic diseases (in nearly all cases by lower cancer mortality and in some cases by lower mortality from cardiovascular diseases (CVD)). This low all-cause mortality often coexists with low respiratory disease mortality and among non-western immigrants, coexists with high mortality from infectious diseases; however, these two causes of death contribute little to mortality among immigrants. For men, CVD is the leading cause of death (particularly among South Asians). For women, cancer is the leading cause of death (except among South Asians, for whom CVD is also the leading cause). Differences in CVD mortality over time remain constant between immigrants relative to UK-born, but immigrant cancer patterns shows signs of some convergence to the cancer mortality among the UK-born (though cancer mortality is still low among immigrants by age 80). The study provides the most up-to-date, reliable UK-based analysis of immigrant mortality. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Morbidade em creche de Brasília: estudo longitudinal de incidência de enfermidades no ano de 1977 Morbidity in a Brasilia day care center: a longitudinal study of disease incidence in 1977

    Directory of Open Access Journals (Sweden)

    Ana Maria Low

    1980-12-01

    Full Text Available Foi feito estudo longitudinal de morbidade em creche de Brasília (Brasil freqüentada por crianças com bom estado nutricional. Foram admitidas na creche durante o ano de 1977 o total de 67 crianças (34 do sexo masculino e 33 do sexo feminino, com idade entre 3 e 21 meses. Infecções de vias aéreas superiores (25,4%, diarréia (23,6% e febre não esclarecida (18,4% representaram dois terços dos diagnósticos. A seguir, em ordem de freqüência, apareceram conjuntivite (15,5%, viroses da infância (7,9%, doenças de pele (3,8%, pequenos acidentes (2,6%, hepatite (2,6% e meningococcemia (0,3%. Houve um total de 343 episódios agudos, dando uma taxa de incidência de 14 enfermidades por criança por ano, independente de sexo e idade.A longitudinal morbidity study was carried out in a day care center in Brasilia (Brazil on a sample of 67 (34 male and 33 female, 3 to 21 months of age well-fed children from middle-class families. A pediatrician was on duty daily in the center. The incidence of disease was: upper respiratory, 25.4%; diarrhea, 23.6%; and undetermined fever, 18.4%. These represented 2/3 of the diagnoses. The other diseases found (and here listed in order of frequency were: conjunctivitis, 15.5%; childhood infections, 7.9%; skin diseases, 3.8%; accidents, 2.6%; hepatitis, 2.6%; and meningitis, 0.3%. There were a total of 343 acute illnesses, giving a mean incidence rate of 14 illnesses per child per year, independent of sex and age. Perhaps the incidence of illnesses would have been lower if the children had not been attending the center, a natural factor in the dissemination of communicable diseases.

  11. Income inequality is associated with adolescent fertility in Brazil: a longitudinal multilevel analysis of 5,565 municipalities.

    Science.gov (United States)

    Chiavegatto Filho, Alexandre D P; Kawachi, Ichiro

    2015-02-07

    Brazil has one of the highest adolescent fertility rates in the world. Income inequality has been frequently linked to overall adolescent health, but studies that analyzed its association with adolescent fertility have been performed only in developed countries. Brazil, in the past decade, has presented a rare combination of increasing per capita income and decreasing income inequality, which could influence future desirable pathways for other countries. We analyzed every live birth from 2000 and from 2010 in each of the 5,565 municipalities of Brazil, a total of 6,049,864 births, which included 1,247,145 (20.6%) births from women aged 15 to 19. Income inequality was assessed by the Gini Coefficient and adolescent fertility by the ratio between the number of live births from women aged 15 to 19 and the number of women aged 15 to 19, calculated for each municipality. We first applied multilevel models separately for 2000 and 2010 to test the cross-sectional association between income inequality and adolescent fertility. We then fitted longitudinal first-differences multilevel models to control for time-invariant effects. We also performed a sensitivity analysis to include only municipality with satisfactory birth record coverage. Our results indicate a consistent and positive association between income inequality and adolescent fertility. After controlling for per capita income, college access, youth homicide rate and adult fertility, higher income inequality was significantly associated with higher adolescent fertility for both 2000 and 2010. The longitudinal multilevel models found similar results. The sensitivity analysis indicated that the results for the association between income inequality and adolescent fertility were robust. Adult fertility was also significantly associated with adolescent fertility in the cross-sectional and longitudinal models. Income inequality is expected to be a leading concern for most countries in the near future. Our results suggest

  12. The neural determinants of age-related changes in fluid intelligence: a pre-registered, longitudinal analysis in UK Biobank.

    Science.gov (United States)

    Kievit, Rogier A; Fuhrmann, Delia; Borgeest, Gesa Sophia; Simpson-Kent, Ivan L; Henson, Richard N A

    2018-01-01

    Background:  Fluid intelligence declines with advancing age, starting in early adulthood. Within-subject declines in fluid intelligence are highly correlated with contemporaneous declines in the ability to live and function independently. To support healthy aging, the mechanisms underlying these declines need to be better understood. Methods:  In this pre-registered analysis, we applied latent growth curve modelling to investigate the neural determinants of longitudinal changes in fluid intelligence across three time points in 185,317 individuals (N=9,719 two waves, N=870 three waves) from the UK Biobank (age range: 39-73 years). Results:  We found a weak but significant effect of cross-sectional age on the mean fluid intelligence score, such that older individuals scored slightly lower. However, the mean longitudinal slope was positive, rather than negative, suggesting improvement across testing occasions. Despite the considerable sample size, the slope variance was non-significant, suggesting no reliable individual differences in change over time. This null-result is likely due to the nature of the cognitive test used. In a subset of individuals, we found that white matter microstructure (N=8839, as indexed by fractional anisotropy) and grey-matter volume (N=9931) in pre-defined regions-of-interest accounted for complementary and unique variance in mean fluid intelligence scores. The strongest effects were such that higher grey matter volume in the frontal pole and greater white matter microstructure in the posterior thalamic radiations were associated with higher fluid intelligence scores. Conclusions:  In a large preregistered analysis, we demonstrate a weak but significant negative association between age and fluid intelligence. However, we did not observe plausible longitudinal patterns, instead observing a weak increase across testing occasions, and no significant individual differences in rates of change, likely due to the suboptimal task design

  13. Association between carotid intima-media thickness and adiponectin in participants without diabetes or cardiovascular disease of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

    Science.gov (United States)

    de Almeida-Pititto, Bianca; Ribeiro-Filho, Fernando Flexa; Santos, Itamar S; Lotufo, Paulo A; Bensenor, Isabela M; Ferreira, Sandra Rg

    2017-01-01

    Objective The study assessed the association of adiponectin concentration with carotid intima-media thickness (CIMT) in middle-aged participants of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) without diabetes or cardiovascular disease. Design Cross-sectional analyses. Methods A sample of 687 individuals (35-54 years old) without diabetes or cardiovascular disease was stratified into two categories according to CIMT (< or ≥ 75th percentile). Traditional risk factors, C-reactive protein and adiponectin values were compared between categories by Student's t-test and frequencies by chi-square test. In linear regression models, associations of CIMT with adiponectin, adjusted for adiposity, blood pressure, C-reactive protein and homeostasis model assessment-insulin resistance were tested. Mean CIMT values were compared across quartiles of adiponectin concentrations using analysis of variance. Results Three hundred and forty-one individuals (49.6%) were women and 130 (19.0%) had three traditional cardiovascular risk factors. Those with elevated CIMT (21.8%) had greater mean values of body mass index (26.2(3.8) vs. 27.7(4.0)kg/m 2 , p < 0.001), waist circumference (86.9(10.1) vs. 90.1(10.8) cm, p = 0.001), systolic blood pressure (116.2(13.6) vs.121.2(16.1) mmHg, p < 0.001), homeostasis model assessment index (1.4(0.9-2.4) vs. 1.8(1.1-2.9), p = 0.011), C-reactive protein (1.2 (0.6-2.6) vs. 1.4(0.8-3.2) mg/l, p = 0.054) and adiponectin (9.9 (6.0-14.7) vs. 8.9 (5.3-13.8) µg/ml, p = 0.002) levels than the counterpart, while plasma glucose and lipids were not different between groups. In the adjusted model, blood pressure (directly) and adiponectin (inversely) persisted associated with high CIMT. Mean CIMT was greater in the first quartile of adiponectin when compared with the other three quartiles ( p = 0.019). Conclusions Lower adiponectin levels together with higher blood pressure were independently associated with

  14. Modifiable predictors of insufficient sleep durations: A longitudinal analysis of youth in the COMPASS study.

    Science.gov (United States)

    Patte, Karen A; Qian, Wei; Leatherdale, Scott T

    2018-01-01

    The purpose of the current study was to simultaneously examine commonly proposed risk and protective factors for sleep deprivation over time among a large cohort of Ontario and Alberta secondary school students. Using 4-year linked longitudinal data from youth in years 1 through 4 (Y 1 [2012/2013], Y 2 [2013/2014], Y 3 [2014/2015], Y 4 [2015/2016]) of the COMPASS study (n=26,205), the likelihood of students meeting contemporary sleep recommendations was tested based on their self-reported substance use, bullying victimization, physical activity, and homework and screen time. Models controlled for the effect of student-reported gender, race/ethnicity, grade, school clustering, and all other predictor variables. Relative to baseline, students became less likely to meet the sleep recommendations if at follow-up they had initiated binge drinking, experienced cyber bullying victimization, or were spending more time doing homework, with other factors held constant. The likelihood of reporting sufficient sleep increased if students had begun engaging in resistance training at least three times a week. No longitudinal effect was observed when students increased their caffeine consumption (energy drinks, coffee/tea), initiated cannabis or tobacco use, experienced other forms of bullying victimization (physical, verbal, or belongings), engaged in more moderate-vigorous physical activity, or increased their screen use of any type. Few of the commonly purported modifiable risk and protective factors for youth sleep deprivation held in multinomial longitudinal analyses. Causal conclusions appear premature, with further research required to confirm the targets likely to be most effective in assisting more youth in meeting the sleep recommendations. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Analysis of the high frequency longitudinal instability of bunched beams using a computer model

    International Nuclear Information System (INIS)

    Messerschmid, E.; Month, M.

    1976-01-01

    The effects of high frequency longitudinal forces on bunched beams are investigated using a computer model. These forces are thought to arise from the transfer of energy between the beam and various structures in the vacuum chamber, this coupling being characterized by a longitudinal impedance function. The simulation is performed with a passive cavity-like element. It is found that the instability can be generated if three conditions are fulfilled: (1) the impedance must be sufficiently large, (2) the induced field must have a fast wake, and (3) the frequency of the induced field must be high enough. In particular, it is shown that the coasting beam threshold criterion for the longitudinal impedance accurately describes the onset of instability, if local values along the bunch of energy spread and current are used. It is also found that the very fast initial growth rate is in good agreement with linear theory and that the coasting beam overshoot expression may be used as a rough guide of the limiting growth for unstable bunches. Concerning the wake field, it is shown how the instability tends to disappear as the fields persist longer. It is furthermore demonstrated that as the wavelength of the unstable mode is increased, initially unstable conditions begin to weaken and vanish. This, it should be emphasized, is primarily a result of the strong correlation between the unstable mode frequency and the time rate of attenuation of the induced fields. ISR parameters are used throughout and a correspondence between the microwave instability observed in the ISR bunches and the simulated instability is suggested. (Auth.)

  16. Estimation of Covariance Matrix on Bi-Response Longitudinal Data Analysis with Penalized Spline Regression

    Science.gov (United States)

    Islamiyati, A.; Fatmawati; Chamidah, N.

    2018-03-01

    The correlation assumption of the longitudinal data with bi-response occurs on the measurement between the subjects of observation and the response. It causes the auto-correlation of error, and this can be overcome by using a covariance matrix. In this article, we estimate the covariance matrix based on the penalized spline regression model. Penalized spline involves knot points and smoothing parameters simultaneously in controlling the smoothness of the curve. Based on our simulation study, the estimated regression model of the weighted penalized spline with covariance matrix gives a smaller error value compared to the error of the model without covariance matrix.

  17. Changes in consumption of added sugars from age 13 to 30 years: a systematic review and meta-analysis of longitudinal studies.

    Science.gov (United States)

    Winpenny, E M; Penney, T L; Corder, K; White, M; van Sluijs, E M F

    2017-11-01

    Added sugar intake during adolescence has been associated with weight gain and cardiometabolic risk factors. Moreover, dietary habits may persist into adulthood, increasing chronic disease risk in later life. This systematic review investigated changes in intake of added sugars between the ages of 13 and 30 years. Literature databases were searched for longitudinal studies of diet during adolescence or early adulthood. Retrieved articles were screened for studies including multiple measures of intake of sugars or sugary foods from cohort participants between the ages of 13 and 30. Data were analysed using random-effects meta-analysis, by the three main nutrient and food group categories identified (PROSPERO: CRD42015030126). Twenty-four papers reported longitudinal data on intake of added sugar or sucrose (n = 6), sugar-sweetened beverages (SSBs) (n = 20) and/or confectionery (n = 9). Meta-analysis showed a non-significant per year of age decrease in added sugar or sucrose intake (-0.15% total energy intake (95%CI -0.41; 0.12)), a decrease in confectionery consumption (-0.20 servings/week (95%CI -0.41; -0.001)) and a non-significant decrease in SSB consumption (-0.15 servings/week (95%CI -0.32; 0.02)). Taken together, the overall decrease in added sugar intake observed from adolescence to early adulthood may suggest opportunities for intervention to further improve dietary choices within this age range. © 2017 The Authors. Obesity Reviews published by John Wiley & Sons Ltd on behalf of World Obesity Federation.

  18. Novel Longitudinal and Propensity Score Matched Analysis of Hands-On Cooking and Nutrition Education versus Traditional Clinical Education among 627 Medical Students

    Directory of Open Access Journals (Sweden)

    Dominique J. Monlezun

    2015-01-01

    Full Text Available Background. Physicians are inadequately equipped to respond to the global obesity and nutrition-associated chronic disease epidemics. We investigated superiority of simulation-based medical education with deliberate practice (SBME-DP hands-on cooking and nutrition elective in a medical school-based teaching kitchen versus traditional clinical education for medical students. Materials and Methods. A 59-question panel survey was distributed to an entire medical school twice annually from September 2012 to May 2014. Student diet and attitudes and competencies (DACs counseling patients on nutrition were compared using conditional multivariate logistic regression, propensity score-weighted, and longitudinal panel analyses. Inverse-variance weighted meta-analysis (IVWM was used for planned subgroup analysis by year and treatment estimates across the three methods. Results. Of the available 954 students, 65.72% (n=627 unique students were followed to produce 963 responses. 11.32% (n=109 of responses were from 84 subjects who participated in the elective. SBME-DP versus traditional education significantly improved fruit and vegetable diet (OR = 1.38, 95% CI: 1.07–1.79, p=0.013 and attitudes (OR = 1.81, 95% CI: 1.40–2.35, p<0.001 and competencies (OR = 1.72, 95% CI: 1.54–1.92, p<0.001. Conclusions. This study reports for the first time superiority longitudinally for SBME-DP style nutrition education for medical students which has since expanded to 13 schools.

  19. Joint analysis of longitudinal feed intake and single recorded production traits in pigs using a novel horizontal model

    DEFF Research Database (Denmark)

    Shirali, M.; Strathe, A. B.; Mark, T.

    2017-01-01

    - and first-order Legendre polynomials of age on test, respectively. The fixed effect and random residual variance were estimated for each weekly FI trait. Residual feed intake (RFI) was derived from the conditional distribution of FI given the breeding values of ADG100 and LMP. The heritability of FI varied......A novel Horizontal model is presented for multitrait analysis of longitudinal traits through random regression analysis combined with single recorded traits. Weekly ADFI on test for Danish Duroc, Landrace, and Yorkshire boars were available from the national test station and were collected from 30...... to 100 kg BW. Single recorded production traits of ADG from birth to 30 kg BW (ADG30), ADG from 30 to 100 kg BW (ADG100), and lean meat percentage (LMP) were available from breeding herds or the national test station. The Horizontal model combined random regression analysis of feed intake (FI...

  20. Regulation and dysregulation of esophageal peristalsis by the integrated function of circular and longitudinal muscle layers in health and disease

    OpenAIRE

    Mittal, Ravinder K.

    2016-01-01

    Muscularis propria throughout the entire gastrointestinal tract including the esophagus is comprised of circular and longitudinal muscle layers. Based on the studies conducted in the colon and the small intestine, for more than a century, it has been debated whether the two muscle layers contract synchronously or reciprocally during the ascending contraction and descending relaxation of the peristaltic reflex. Recent studies in the esophagus and colon prove that the two muscle layers indeed c...

  1. A longitudinal analysis of maternal depressive symptoms and children's food consumption and weight outcomes.

    Science.gov (United States)

    Morrissey, Taryn W; Dagher, Rada K

    2014-12-01

    Maternal depressive symptoms negatively impact mothers' parenting practices and children's development, but the evidence linking these symptoms to children's obesity is mixed. We use a large sample to examine contemporaneous and lagged associations between maternal depressive symptoms and children's BMI, obesity and food consumption, controlling for background characteristics. Data from the Early Childhood Longitudinal Study-Birth Cohort (ECLS-B), a longitudinal study of children from infancy through kindergarten in the USA, were collected at four waves from 2001 to 2007, when children were 9 months, 2 years, 4 years and 5½years of age, through surveys, child assessments and observations. A sub-sample of children from the ECLS-B is used (n 6500). Between 17 % and 19 % of mothers reported experiencing depressive symptoms; 17 % to 20 % of children were obese. Maternal depressive symptoms were associated with a small decrease in the likelihood her child was obese (0·8 percentage points) and with lower consumption of healthy foods. The duration of maternal depressive symptoms was associated with higher BMI (0·02 sd) among children whose parents lacked college degrees. Results indicate that mothers' depressive symptoms have small associations with children's food consumption and obesity. Among children whose parents lack college degrees, persistent maternal depressive symptoms are associated with slightly higher child BMI. Findings highlight the need to control for depression in analyses of children's weight. Interventions that consider maternal depression early may be useful in promoting healthy weight outcomes and eating habits among children.

  2. Parenting stress mediates the association between negative affectivity and harsh parenting: A longitudinal dyadic analysis.

    Science.gov (United States)

    Le, Yunying; Fredman, Steffany J; Feinberg, Mark E

    2017-09-01

    The current study examined parenting stress (disaggregated into personal distress and child rearing stress) at 12 months postpartum as a mediator of the longitudinal association between parental negative affectivity at 6 months postpartum and harsh parenting at 3 years postpartum for first-time parents with a child transitioning from late toddlerhood to the early preschool years. Analyses were conducted using Mediation for Actor Partner Interdependence Modeling in a sample of 164 couples who participated in a randomized controlled trial of a universal, couple-based transition to parenthood program. There were indirect actor effects of negative affect on a parent's own harsh parenting through both dimensions of parenting stress, with a stronger mediating effect for personal distress than child rearing stress. There were also indirect partner effects of negative affect on one's partner's harsh parenting through the partner's parenting stress, with a stronger indirect partner effect from mothers' negative affect to fathers' harsh parenting than vice versa. Specifically, the mediating effect of personal distress was found for both mothers and fathers, whereas the mediating effect of child rearing stress was found from mothers' negative affect to fathers' harsh parenting only. Findings highlight the importance of a dyadic approach in examining the longitudinal association between negative affect and harsh parenting and suggest that reducing parenting stress in the first year postpartum may decrease the risk of future harsh parenting among couples in which one or both partners experience negative affectivity. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  3. Workplace Bullying and Mental Health: A Meta-Analysis on Cross-Sectional and Longitudinal Data

    Science.gov (United States)

    2015-01-01

    Background A growing body of research has confirmed that workplace bullying is a source of distress and poor mental health. Here we summarize the cross-sectional and longitudinal literature on these associations. Methods Systematic review and meta-analyses on the relation between workplace bullying and mental health. Results The cross-sectional data (65 effect sizes, N = 115.783) showed positive associations between workplace bullying and symptoms of depression (r = .28, 95% CI = .23–.34), anxiety (r = .34, 95% CI = .29–.40) and stress-related psychological complaints (r = .37, 95% CI = .30–.44). Pooling the literature that investigated longitudinal relationships (26 effect sizes, N = 54.450) showed that workplace bullying was related to mental health complaints over time (r = 0.21, 95% CI = 0.13–0.21). Interestingly, baseline mental health problems were associated with subsequent exposure to workplace bullying (r = 0.18, 95% CI = 0.10–0.27; 11 effect sizes, N = 27.028). Limitations All data were self-reported, raising the possibility of reporting- and response set bias. Conclusions Workplace bullying is consistently, and in a bi-directional manner, associated with reduced mental health. This may call for intervention strategies against bullying at work. PMID:26305785

  4. A Multilevel, Longitudinal Analysis of Middle School Math and Language Achievement

    Directory of Open Access Journals (Sweden)

    Keith Zvoch

    2003-07-01

    Full Text Available The performance of schools in a large urban school district was examined using achievement data from a longitudinally matched cohort of middle school students. Schools were evaluated in terms of the mean achievement and mean growth of students in mathematics and language arts. Application of multilevel, longitudinal models to student achievement data revealed that 1 school performance varied across both outcome measures in both subject areas, 2 significant proportions of variation were associated with school-to-school differences in performance, 3 evaluations of school performance differed depending on whether school mean achievement or school mean growth in achievement was examined, and 4 school mean achievement was a weak predictor of school mean growth. These results suggest that assessments of school performance depend on choices of how data are modeled and analyzed. In particular, the present study indicates that schools with low mean scores are not always “poor performing” schools. Use of student growth rates to evaluate school performance enables schools that would otherwise be deemed low performing to demonstrate positive effects on student achievement. Implications for state accountability systems are discussed.

  5. [Antecedents and consequences of workplace bullying: a longitudinal analysis with a structural equation model].

    Science.gov (United States)

    Carretero Domínguez, Noelia; Gil-Monte, Pedro Rafael; Luciano Devis, Juan Vicente

    2011-11-01

    Most studies focusing on the antecedents and consequences of workplace bullying have used a cross-sectional design, which impedes determining the causality of the relationships. In the present work, we analyzed, by means of structural equation models, the relationship between workplace bullying and some variables that are considered antecedents (interpersonal conflicts, role ambiguity, role conflict, and workplace social support) or consequences (health complaints and inclination to absenteeism from work) of this phenomenon. Multicenter study with two phases. The sample consisted of 696 employees from 66 centers. Workplace bullying was assessed by means of the "Mobbing-UNIPSICO" questionnaire, and the other variables with frequency scales. The cross-sectional models indicated a significant association between role conflict, workplace social support, and workplace bullying in both study periods. Concerning the longitudinal relationships, only workplace social support was a significant predictor of workplace bullying, which, in turn, was a cross-sectional and longitudinal predictor of workers' health complaints. Our results show the mediating effect of workplace bullying between certain work conditions and health complaints, and it is recommendable to replicate these findings in a multi-occupational sample.

  6. Workplace Bullying and Mental Health: A Meta-Analysis on Cross-Sectional and Longitudinal Data.

    Directory of Open Access Journals (Sweden)

    Bart Verkuil

    Full Text Available A growing body of research has confirmed that workplace bullying is a source of distress and poor mental health. Here we summarize the cross-sectional and longitudinal literature on these associations.Systematic review and meta-analyses on the relation between workplace bullying and mental health.The cross-sectional data (65 effect sizes, N = 115.783 showed positive associations between workplace bullying and symptoms of depression (r = .28, 95% CI = .23-.34, anxiety (r = .34, 95% CI = .29-.40 and stress-related psychological complaints (r = .37, 95% CI = .30-.44. Pooling the literature that investigated longitudinal relationships (26 effect sizes, N = 54.450 showed that workplace bullying was related to mental health complaints over time (r = 0.21, 95% CI = 0.13-0.21. Interestingly, baseline mental health problems were associated with subsequent exposure to workplace bullying (r = 0.18, 95% CI = 0.10-0.27; 11 effect sizes, N = 27.028.All data were self-reported, raising the possibility of reporting- and response set bias.Workplace bullying is consistently, and in a bi-directional manner, associated with reduced mental health. This may call for intervention strategies against bullying at work.

  7. Workplace Bullying and Mental Health: A Meta-Analysis on Cross-Sectional and Longitudinal Data.

    Science.gov (United States)

    Verkuil, Bart; Atasayi, Serpil; Molendijk, Marc L

    2015-01-01

    A growing body of research has confirmed that workplace bullying is a source of distress and poor mental health. Here we summarize the cross-sectional and longitudinal literature on these associations. Systematic review and meta-analyses on the relation between workplace bullying and mental health. The cross-sectional data (65 effect sizes, N = 115.783) showed positive associations between workplace bullying and symptoms of depression (r = .28, 95% CI = .23-.34), anxiety (r = .34, 95% CI = .29-.40) and stress-related psychological complaints (r = .37, 95% CI = .30-.44). Pooling the literature that investigated longitudinal relationships (26 effect sizes, N = 54.450) showed that workplace bullying was related to mental health complaints over time (r = 0.21, 95% CI = 0.13-0.21). Interestingly, baseline mental health problems were associated with subsequent exposure to workplace bullying (r = 0.18, 95% CI = 0.10-0.27; 11 effect sizes, N = 27.028). All data were self-reported, raising the possibility of reporting- and response set bias. Workplace bullying is consistently, and in a bi-directional manner, associated with reduced mental health. This may call for intervention strategies against bullying at work.

  8. Work engagement or burnout: Which comes first? A meta-analysis of longitudinal evidence

    Directory of Open Access Journals (Sweden)

    Laurențiu P. Maricuțoiu

    2017-06-01

    Full Text Available Currently, burnout (BU and work engagement (WE and are considered different forms of workplace well-being, negatively related that might even co-occur, or as direct opposites and mutually exclusive. These contrasting views generate difficulties regarding the true nature of the relationship between the two concepts. In the present paper, we aim at clarifying this issue by testing the cross-lagged effects between BU and WE. We conducted systematic database searches using keywords relevant for WE, BU and design type (e.g., longitudinal, and we found 25 eligible research studies (Ntotal = 13271 participants. The selected papers a reported a longitudinal research study; b included measures of BU and WE, and c reported the correlation matrix between BU and WE at all measurement moments. First, we used meta-analytical formulas to compute the averaged correlations between BU and WE. Second, we used the averaged effects to complete a correlation matrix, which was used to test the cross-lagged effects between BU and WE, using structural equations modeling. On the entire sample of studies, we found insignificant cross-lagged effects between BU and WE. However, when the time-lag between the two measurement moments was used as a moderator, significant reciprocal cross-lagged effects were found between exhaustion and WE, at 12-month time lag. Notably, it appears that the validity of causal perspective depends on the size of the time lag.

  9. Adaptive Quantification and Longitudinal Analysis of Pulmonary Emphysema with a Hidden Markov Measure Field Model

    Science.gov (United States)

    Häme, Yrjö; Angelini, Elsa D.; Hoffman, Eric A.; Barr, R. Graham; Laine, Andrew F.

    2014-01-01

    The extent of pulmonary emphysema is commonly estimated from CT images by computing the proportional area of voxels below a predefined attenuation threshold. However, the reliability of this approach is limited by several factors that affect the CT intensity distributions in the lung. This work presents a novel method for emphysema quantification, based on parametric modeling of intensity distributions in the lung and a hidden Markov measure field model to segment emphysematous regions. The framework adapts to the characteristics of an image to ensure a robust quantification of emphysema under varying CT imaging protocols and differences in parenchymal intensity distributions due to factors such as inspiration level. Compared to standard approaches, the present model involves a larger number of parameters, most of which can be estimated from data, to handle the variability encountered in lung CT scans. The method was used to quantify emphysema on a cohort of 87 subjects, with repeated CT scans acquired over a time period of 8 years using different imaging protocols. The scans were acquired approximately annually, and the data set included a total of 365 scans. The results show that the emphysema estimates produced by the proposed method have very high intra-subject correlation values. By reducing sensitivity to changes in imaging protocol, the method provides a more robust estimate than standard approaches. In addition, the generated emphysema delineations promise great advantages for regional analysis of emphysema extent and progression, possibly advancing disease subtyping. PMID:24759984

  10. Longitudinal burnout-collaboration patterns in Japanese medical care workers at special needs schools: a latent class growth analysis

    Science.gov (United States)

    Kanayama, Mieko; Suzuki, Machiko; Yuma, Yoshikazu

    2016-01-01

    The present study aimed to identify and characterize potential burnout types and the relationship between burnout and collaboration over time. Latent class growth analysis and the growth mixture model were used to identify and characterize heterogeneous patterns of longitudinal stability and change in burnout, and the relationship between burnout and collaboration. We collected longitudinal data at three time points based on Japanese academic terms. The 396 study participants included academic teachers, yogo teachers, and registered nurses in Japanese special needs schools. The best model included four types of both burnout and collaboration in latent class growth analysis with intercept, slope, and quadratic terms. The four types of burnout were as follows: low stable, moderate unstable, high unstable, and high decreasing. They were identified as involving inverse collaboration function. The results indicated that there could be dynamic burnout types, namely moderate unstable, high unstable, and high decreasing, when focusing on growth trajectories in latent class analyses. The finding that collaboration was dynamic for dynamic burnout types and stable for stable burnout types is of great interest. This was probably related to the inverse relationship between the two constructs. PMID:27366107

  11. Sibling analysis of adolescent intelligence and chronic diseases in older adulthood.

    Science.gov (United States)

    Jokela, Markus; Batty, G David; Deary, Ian J; Silventoinen, Karri; Kivimäki, Mika

    2011-07-01

    We examined whether associations of adolescent intelligence with chronic diseases in adulthood are explained by socioeconomic factors, health behaviors, or common sources of variance in intelligence and chronic disease risk. A prospective cohort study (Wisconsin Longitudinal Study) of high school graduates and their siblings with intelligence assessed in adolescence and chronic diseases reported in adulthood (n = 10,168; mean age 53.9 and n = 9051; mean age 64.8 in two follow-ups). After adjustment for age and sex, greater intelligence was associated with lower risk of heart disease (odds ratio per 1 SD advantage in intelligence 0.93; 95% confidence interval 0.87-0.99), circulation problems (0.85; 0.79-0.92), stroke (0.80; 0.70-0.91), and diabetes (0.88; 0.81-0.95). Participants' risk of stroke and circulation problems also was predicted by their sibling's intelligence, suggesting potential common causes for intelligence and cerebrovascular diseases. Sibling analysis provided no support for shared family environment in explaining associations between intelligence and disease outcomes because between-families and within-siblings regression models were not different. Adjusting for common risk factors had little impact on these associations. In contrast, adjusting for adult socioeconomic status attenuated the associations by 25%-100% (66% on average). Multiple mechanisms may link intelligence with occurrence of chronic diseases of major public health importance. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Diabetes as an independent predictor of left ventricular longitudinal strain reduction at rest and during dobutamine stress test in patients with significant coronary artery disease.

    Science.gov (United States)

    Wierzbowska-Drabik, Karina; Trzos, Ewa; Kurpesa, Malgorzata; Rechcinski, Tomasz; Miskowiec, Dawid; Cieslik-Guerra, Urszula; Uznanska-Loch, Barbara; Sobczak, Maria; Kasprzak, Jaroslaw Damian

    2017-12-09

    Diabetes (DM) is a strong cardiovascular risk factor modifying also the left ventricular (LV) function that may be objectively assessed with echocardiographic strain analysis. Although the impact of isolated DM on myocardial deformation has been already studied, few data concern diabetics with coronary artery disease (CAD), especially in all stages of dobutamine stress echocardiography (DSE). We compared LV systolic function during DSE in CAD with and without DM using state-of-the art speckle-tracking quantification and assessed the impact of DM on LV systolic strain. DSE was performed in 250 patients with angina who afterwards had coronarography with ≥50% stenosis in the left main artery and ≥70% in other arteries considered as significant. In this analysis, we included 127 patients with confirmed CAD: 42 with DM [DM(+); mean age 64 ± 9 years] and 85 patients without DM [DM(-); mean age 63 ± 9 years]. The severity of CAD and LV ejection fraction (EF) were similar in both groups. Global and regional LV peak systolic longitudinal strain (PSLS) revealed in all DSE phases lower values in DM(+) group: 14.5 ± 3.6% vs. 17.4 ± 4.0% at rest; P = 0.0001, 13.8 ± 3.9% vs. 16.7 ± 4.0% at peak stress; P = 0.0002, and 14.2 ± 3.1% vs. 15.5 ± 3.5% at recovery; P = 0.0432 for global parameters, although dobutamine challenge did not enhance further resting differences. LV EF, body surface area, and diabetes were independent predictors for strain in 16-variable model (R2 = 0, 51, P coexisting CAD and DM on myocardial strain. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

  13. A New Approach to Assess Lifetime Dietary Patterns Finds Lower Consumption of Animal Foods with Aging in a Longitudinal Analysis of a Health-Oriented Adventist Population

    Science.gov (United States)

    Martins, Marcia C. T.; Jaceldo-Siegl, Karen; Fan, Jing; Mashchak, Andrew

    2017-01-01

    Life-course diet patterns may impact risk of disease, but little is known about dietary trends with aging. In a retrospective longitudinal analysis we estimated lifetime intake of animal products and adherence to vegetarian dietary patterns among 51,082 Adventist Health Study-2 (AHS-2) subjects using data from a reliable life-course dietary (meats, dairy, eggs) questionnaire. Results showed a marked tendency to consume fewer animal products (in total) in older years and to reduce consumption of meat, poultry and fish, but not eggs or dairy. Among the 29% of elderly subjects who during their lifetime kept the same dietary pattern (LTS) were: LTS-vegans (1.1%), LTS-lacto-ovo vegetarians (31.2%), LTS-pesco vegetarians (0.49%), LTS-semi vegetarians (3.7%), and LTS-non-vegetarians (63.5%). Among the 71% of switchers were “Converters” (59.7%) who moved towards and “Reverters” (9.1%) who moved away from vegetarian diets, and Multiverters (31.2%), who had moved in both directions. LTS-non-vegetarians, and also reverters, were more overweight and showed a less healthy lifestyle than others. We conclude that the dietary patterns are dynamic with strong trends to reduce animal foods and to adopt more vegetarian patterns with aging. The disease experience of subjects with different lifetime dietary patterns can be compared. PMID:29027960

  14. A longitudinal analysis of bibliometric and impact factor trends among the core international journals of nursing, 1977-2008.

    Science.gov (United States)

    Smith, Derek R

    2010-12-01

    Although bibliometric analysis affords significant insight into the progression and distribution of information within a particular research field, detailed longitudinal studies of this type are rare within the field of nursing. This study aimed to investigate, from a bibliometric perspective, the progression and trends of core international nursing journals over the longest possible time period. A detailed bibliometric analysis was undertaken among 7 core international nursing periodicals using custom historical data sourced from the Thomson Reuters Journal Citation Reports®. In the 32 years between 1977 and 2008, the number of citations received by these 7 journals increased over 700%. A sustained and statistically significant (pnursing. Impressive and continual impact factor gains suggest that published nursing research is being increasingly seen, heard and cited in the international academic community. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Corporate Foresight and its Impact on Firm Performance: A Longitudinal Analysis

    DEFF Research Database (Denmark)

    Rohrbeck, René; Kum, Menes Etingue

    2018-01-01

    ’s future preparedness (FP) by assessing the need for corporate foresight (CF) and comparing it to the maturity of its CF practices. We apply a longitudinal research design in which we measure future preparedness in 2008 and its impact on firm performance in 2015. The results indicated future preparedness......Corporate foresight is applied with the expectation that it will help firms to break away from path dependency, help decision makers to define superior courses of action, and ultimately enable superior firm performance. To empirically test this assumption, we developed a model that judges a firm...... to be a powerful predictor for becoming an outperformer in the industry, for attaining superior profitability, and for gaining superior market capitalization growth. In the article, we also calculate the average bonus/discount that can be expected by sufficiently/insufficiently future-prepared firms....

  16. Analysis of the braking longitudinal force considered by NBR7187 (2003 through a case study

    Directory of Open Access Journals (Sweden)

    G. C. Bettazzi

    Full Text Available This paper analyzed the mechanical behavior of a railway bridge by the Finite Element Method and by monitoring strain deformations with extensometry during its operation. To represent the situations that occur in its operation, tests were made with train braking. The results of monitoring the bottom cross section of column P15 of the bridge are presented. Based on the obtained data, the deformations occurring during the tests are verified against the calculated values obtained by the FEM method and those prescribed by NBR 7187(2003. The comparison between the real behavior of the structure, recorded experimentally through extensometry, and the numerical forecast and its assumptions from the project conceived was done. From this comparison, it verified that the value of longitudinal force due to braking recommended by the standard is appropriate.

  17. Stability and accuracy of metamemory in adulthood and aging: a longitudinal analysis.

    Science.gov (United States)

    McDonald-Miszczak, L; Hertzog, C; Hultsch, D F

    1995-12-01

    The stability and accuracy of memory perceptions in 2 longitudinal samples was examined. Sample 1 consisted of 231 adults (22-78 years) tested twice over 2 years. Sample 2 consisted of 234 adults (55-86 years) tested 3 times over 6 years. Measures of perceived and actual memory change were obtained. A primary focus was whether perceptions of memory change stem from application of an implicit theory about aging and memory or from accurate monitoring of actual changes in performance. Individual differences in metamemory were highly stable over time. Results suggested at least some accurate monitoring of memory in Sample 2, in which actual change was greatest. However the overall pattern of results is largely consistent with predictions derived from an implicit theory hypothesis.

  18. Divorce, approaches to learning, and children's academic achievement: a longitudinal analysis of mediated and moderated effects.

    Science.gov (United States)

    Anthony, Christopher J; DiPerna, James Clyde; Amato, Paul R

    2014-06-01

    Data from the Early Childhood Longitudinal Study--Kindergarten Cohort (ECLS-K) were used to test the hypothesis that approaches to learning (ATL) mediates the link between parental divorce and academic achievement. Fixed effects regression was utilized to test for mediation, and subsequent moderation analyses examining gender and age at time of divorce also were conducted. Results indicated that divorce was associated with less growth in test scores and that ATL mediated 18% and 12% of this association in reading and mathematics respectively. Parental divorce also was associated with larger negative effects for children who experienced divorce at an older age as well as for girls' mathematics test scores. These findings contribute to the understanding of the impact of parental divorce on children's academic achievement and underscore the importance of focusing on the variability of child outcomes following parental divorce. Copyright © 2014 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

  19. Personality, work characteristics, and employee well-being: a longitudinal analysis of additive and moderating effects.

    Science.gov (United States)

    Houkes, Inge; Janssen, Peter P M; de Jonge, Jan; Bakker, Arnold B

    2003-01-01

    This study tested the longitudinal influence of personality (measured by the characteristics growth need strength, negative affectivity [NA], and upward striving) on 3 psychological outcomes (intrinsic work motivation, emotional exhaustion, and turnover intention), using a pattern of specific relationships between work characteristics and these outcomes as a framework. The study hypotheses were tested in a multioccupational sample consisting of bank employees and teachers, using a 2-wave panel design with a 1-year time interval and structural equation modeling. NA had a cross-lagged direct and additive relationship with emotional exhaustion and also moderated the relationship between Time 1 workload and Time 2 emotional exhaustion. The authors concluded that NA may have multiple effects on emotional exhaustion that persist over time.

  20. Criteria for analysis and optimization of longitudinal fins with convective tip

    International Nuclear Information System (INIS)

    Gomes, E.S.

    1983-01-01

    The problem of heat transfer in longitudinal fins with the main geometries used in equipaments of heat transfer by convection is analyzed. The equation of energy is solved analytically of several geometries fins, with unidimensional formulation, through the use of the convective heat transfer coefficient. The problem of fin optimization is approached analytically yielding the parameters which allow the maximum heat transfer for each particular material waste in the fin. The use of the insulated tip model suggests the use of fins and its optimization for any Biot number of the fin. The use of the convective tip model allows us to determine when is vantageous or disadvantageous to use fins and when fin optimization is possible according to the value of the Biot number and to a convection parameter on the fin tip. (Author) [pt

  1. Self-rated health in Canadian immigrants: analysis of the Longitudinal Survey of Immigrants to Canada.

    Science.gov (United States)

    Setia, Maninder Singh; Lynch, John; Abrahamowicz, Michal; Tousignant, Pierre; Quesnel-Vallee, Amelie

    2011-03-01

    Using a multi-level random effects logistic model, we examine the contribution of source country, individual characteristics and post-migration experiences to the self-rated health (SRH) of 2468 male and 2614 female immigrants from the Longitudinal Survey of Immigrants to Canada (2001-2005). Sex/gender differences were found for all categories of health determinants. Source country characteristics explained away some ethnic differentials in health and had independent negative effects, particularly among women. Thus, women from countries lower on the development index appear at greater risk of poor SRH, and should be at the forefront of public health programmes aimed at new immigrants in Canada. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Indigenous migration dynamics in the Ecuadorian Amazon: a longitudinal and hierarchical analysis.

    Science.gov (United States)

    Davis, Jason; Sellers, Samuel; Gray, Clark; Bilsborrow, Richard

    2017-01-01

    Amazonian indigenous populations are approaching a critical stage in their history in which increasing education and market integration, rapid population growth and degradation of natural resources threaten the survival of their traditions and livelihoods. A topic that has hardly been touched upon in this context is migration and population mobility. We address this by analysing a unique longitudinal dataset from the Ecuadorian Amazon on the spatial mobility of five indigenous groups and mestizo co-residents. Analyses reveal traditional and new forms of population mobility and migrant selectivity, including gendered forms of marriage migration and rural-urban moves driven by education. These results illustrate a dynamic present and an uncertain future for indigenous populations in which rural, natural-resource-based lifeways may well be sustained but with increasing links to urban areas.

  3. Falls among community-residing stroke survivors following inpatient rehabilitation: a descriptive analysis of longitudinal data

    Directory of Open Access Journals (Sweden)

    Hunsaker Amanda E

    2009-10-01

    Full Text Available Abstract Background Stroke victims are at relatively high risk for injurious falls. The purpose of this study was to document longitudinal fall patterns following inpatient rehabilitation for first-time stroke survivors. Methods Participants (n = 231 were recruited at the end of their rehab stay and interviewed monthly via telephone for 1 to 32 months regarding fall incidents. Analyses were conducted on: total reports of falls by month over time for first-time and repeat fallers, the incidence of falling in any given month; and factors differing between fallers and non fallers. Results The largest percentage of participants (14% reported falling in the first month post-discharge. After month five, less than 10% of the sample reported falling, bar months 15 (10.4% and 23 (13.2%. From months one to nine, the percentage of those reporting one fall with and without a prior fall were similar. After month nine, the number of individuals who reported a single fall with a fall history was twice as high compared to those without a prior fall who reported falling. In both cases the percentages were small. A very small subset of the population emerged who fell multiple times each month, most of whom had a prior fall history. At least a third of the sample reported a loss of balance each month. Few factors differed significantly between fallers and non-fallers in months one to six. Conclusion Longitudinal data suggest that falls most likely linked to first time strokes occur in the first six months post discharge, particularly month one. Data routinely available at discharge does not distinguish fallers from non-fallers. Once a fall incident has occurred however, preventive intervention is warranted.

  4. Nonlinear mixed effects modelling for the analysis of longitudinal body core temperature data in healthy volunteers.

    Science.gov (United States)

    Seng, Kok-Yong; Chen, Ying; Wang, Ting; Ming Chai, Adam Kian; Yuen Fun, David Chiok; Teo, Ya Shi; Sze Tan, Pearl Min; Ang, Wee Hon; Wei Lee, Jason Kai

    2016-04-01

    Many longitudinal studies have collected serial body core temperature (T c) data to understand thermal work strain of workers under various environmental and operational heat stress environments. This provides the opportunity for the development of mathematical models to analyse and forecast temporal T c changes across populations of subjects. Such models can reduce the need for invasive methods that continuously measure T c. This current work sought to develop a nonlinear mixed effects modelling framework to delineate the dynamic changes of T c and its association with a set of covariates of interest (e.g. heart rate, chest skin temperature), and the structure of the variability of T c in various longitudinal studies. Data to train and evaluate the model were derived from two laboratory investigations involving male soldiers who participated in either a 12 (N  =  18) or 15 km (N  =  16) foot march with varied clothing, load and heat acclimatisation status. Model qualification was conducted using nonparametric bootstrap and cross validation procedures. For cross validation, the trajectory of a new subject's T c was simulated via Bayesian maximum a posteriori estimation when using only the baseline T c or using the baseline T c as well as measured T c at the end of every work (march) phase. The final model described T c versus time profiles using a parametric function with its main parameters modelled as a sigmoid hyperbolic function of the load and/or chest skin temperature. Overall, T c predictions corresponded well with the measured data (root mean square deviation: 0.16 °C), and compared favourably with those provided by two recently published Kalman filter models.

  5. Cognitive behavioural therapy for MS-related fatigue explained: A longitudinal mediation analysis.

    Science.gov (United States)

    van den Akker, L E; Beckerman, H; Collette, E H; Knoop, H; Bleijenberg, G; Twisk, J W; Dekker, J; de Groot, V

    2018-03-01

    Cognitive behavioural therapy (CBT) effectively reduces fatigue directly following treatment in patients with Multiple Sclerosis (MS), but little is known about the process of change during and after CBT. Additional analysis of a randomized clinical trial. To investigate which psychological factors mediate change in fatigue during and after CBT. TREFAMS-CBT studied the effectiveness of a 16-week CBT treatment for MS-related fatigue. Ninety-one patients were randomized (44 to CBT, 47 to the MS-nurse consultations). Mediation during CBT treatment was studied using assessments at baseline, 8 and 16weeks. Mediation of the change in fatigue from post-treatment to follow-up was studied separately using assessments at 16, 26 and 52weeks. Proposed mediators were: changes in illness cognitions, general self-efficacy, coping styles, daytime sleepiness, concentration and physical activity, fear of disease progression, fatigue perceptions, depression and physical functioning. Mediators were separately analysed according to the product-of-coefficients approach. Confidence intervals were calculated with a bootstrap procedure. During treatment the decrease in fatigue brought on by CBT was mediated by improved fatigue perceptions, increased physical activity, less sleepiness, less helplessness, and improved physical functioning. Post-treatment increases in fatigue levels were mediated by reduced physical activity, reduced concentration, and increased sleepiness. These results suggests that focusing on improving fatigue perceptions, perceived physical activity, daytime sleepiness, helplessness, and physical functioning may further improve the effectiveness of CBT for fatigue in patients with MS. Maintenance of treatment effects may be obtained by focusing on improving physical activity, concentration and sleepiness. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. Cluster Analysis on Longitudinal Data of Patients with Adult-Onset Asthma.

    Science.gov (United States)

    Ilmarinen, Pinja; Tuomisto, Leena E; Niemelä, Onni; Tommola, Minna; Haanpää, Jussi; Kankaanranta, Hannu

    Previous cluster analyses on asthma are based on cross-sectional data. To identify phenotypes of adult-onset asthma by using data from baseline (diagnostic) and 12-year follow-up visits. The Seinäjoki Adult Asthma Study is a 12-year follow-up study of patients with new-onset adult asthma. K-means cluster analysis was performed by using variables from baseline and follow-up visits on 171 patients to identify phenotypes. Five clusters were identified. Patients in cluster 1 (n = 38) were predominantly nonatopic males with moderate smoking history at baseline. At follow-up, 40% of these patients had developed persistent obstruction but the number of patients with uncontrolled asthma (5%) and rhinitis (10%) was the lowest. Cluster 2 (n = 19) was characterized by older men with heavy smoking history, poor lung function, and persistent obstruction at baseline. At follow-up, these patients were mostly uncontrolled (84%) despite daily use of inhaled corticosteroid (ICS) with add-on therapy. Cluster 3 (n = 50) consisted mostly of nonsmoking females with good lung function at diagnosis/follow-up and well-controlled/partially controlled asthma at follow-up. Cluster 4 (n = 25) had obese and symptomatic patients at baseline/follow-up. At follow-up, these patients had several comorbidities (40% psychiatric disease) and were treated daily with ICS and add-on therapy. Patients in cluster 5 (n = 39) were mostly atopic and had the earliest onset of asthma, the highest blood eosinophils, and FEV 1 reversibility at diagnosis. At follow-up, these patients used the lowest ICS dose but 56% were well controlled. Results can be used to predict outcomes of patients with adult-onset asthma and to aid in development of personalized therapy (NCT02733016 at ClinicalTrials.gov). Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Early Expansion of the Intracranial CSF Volume After Palliative Whole-Brain Radiotherapy: Results of a Longitudinal CT Segmentation Analysis

    International Nuclear Information System (INIS)

    Sanghera, Paul; Gardner, Sandra L.; Scora, Daryl; Davey, Phillip

    2010-01-01

    Purpose: To assess cerebral atrophy after radiotherapy, we measured intracranial cerebrospinal fluid volume (ICSFV) over time after whole-brain radiotherapy (WBRT) and compared it with published normal-population data. Methods and Materials: We identified 9 patients receiving a single course of WBRT (30 Gy in 10 fractions over 2 weeks) for ipsilateral brain metastases with at least 3 years of computed tomography follow-up. Segmentation analysis was confined to the tumor-free hemi-cranium. The technique was semiautomated by use of thresholds based on scanned image intensity. The ICSFV percentage (ratio of ICSFV to brain volume) was used for modeling purposes. Published normal-population ICSFV percentages as a function of age were used as a control. A repeated-measures model with cross-sectional (between individuals) and longitudinal (within individuals) quadratic components was fitted to the collected data. The influence of clinical factors including the use of subependymal plate shielding was studied. Results: The median imaging follow-up was 6.25 years. There was an immediate increase (p < 0.0001) in ICSFV percentage, which decelerated over time. The clinical factors studied had no significant effect on the model. Conclusions: WBRT immediately accelerates the rate of brain atrophy. This longitudinal study in patients with brain metastases provides a baseline against which the potential benefits of more localized radiotherapeutic techniques such as radiosurgery may be compared.

  8. A longitudinal analysis of the effects of different patterns of employment and unemployment on school-leavers.

    Science.gov (United States)

    Feather, N T; O'Brien, G E

    1986-11-01

    Large samples of young employed and unemployed respondents in metropolitan Adelaide, South Australia, completed questionnaires on two occasions one year apart. A wide range of variables was assessed that included measures of aspects of the self-concept, Protestant Ethic values, desired work values, stress symptoms, life satisfaction, unemployment disappointment, job need, employment value, external control and attributions for youth unemployment. There was little evidence from longitudinal analyses of change scores that a shift from employment to unemployment or the reverse transition had significant effects on psychological well-being, but unemployment attributions were affected. The shift from employment to unemployment led to less internal and more external causal attributions for youth unemployment; the reverse transition had the opposite effects. Cross-sectional comparisons of findings from the employed and unemployed samples replicated previous results that were consistent with the conclusion that many of the obtained differences were present when respondents were still at school. Variables assumed to reflect employment importance did not have moderating effects on psychological well-being when employed and unemployed groups were compared in either longitudinal or cross-sectional analyses but they were involved in significant associations with other measures. Results suggested the need for more empirical and conceptual analysis of the concepts of psychological well-being and employment importance.

  9. Optimization analysis of convective–radiative longitudinal fins with temperature-dependent properties and different section shapes and materials

    International Nuclear Information System (INIS)

    Mosayebidorcheh, S.; Hatami, M.; Mosayebidorcheh, T.; Ganji, D.D.

    2015-01-01

    Graphical abstract: Temperature distribution along the fins obtained for different material and section shapes. - Highlights: • The steady state thermal analysis of longitudinal fins is presented. • The properties of fins are assumed as a function of temperature. • The rectangular, convex, triangular and concave profiles are considered for fin shape. • Least Square Method (LSM) is used for solving the governing equation. • Thermal optimization of fin geometry is presented based on maximum value of heat transfer. - Abstract: The main aim of this study is to obtain an optimum design point for fin geometry, so that heat transfer rate reaches to a maximum value in a constant fin volume. Effect of fin thicknesses ratio (τ), convection coefficient power index (m), profile power parameter (n), base thickness (δ) and fin material are evaluated in the fin optimization point for heat transfer rate, effectiveness and efficiency. It’s assumed that the thickness of longitudinal fins varies with length in a special profile, so four different shapes (rectangular, convex, triangular and concave) are considered. In present study, temperature-dependent heat generation, convection and radiation are considered and an analytical technique based on the least square method is proposed for the solution methodology. Results show that by increasing the fin thicknesses ratio, maximum heat transfer rate decreases and Copper among the other materials has the most heat transfer rate in a constant volume.

  10. Sickness absence and psychosocial job quality: an analysis from a longitudinal survey of working Australians, 2005-2012.

    Science.gov (United States)

    Milner, Allison; Butterworth, Peter; Bentley, Rebecca; Kavanagh, Anne M; LaMontagne, Anthony D

    2015-05-15

    Sickness absence is associated with adverse health, organizational, and societal outcomes. Using data from a longitudinal cohort study of working Australians (the Household, Income and Labour Dynamics in Australia (HILDA) Survey), we examined the relationship between changes in individuals' overall psychosocial job quality and variation in sickness absence. The outcome variables were paid sickness absence (yes/no) and number of days of paid sickness absence in the past year (2005-2012). The main exposure variable was psychosocial job quality, measured using a psychosocial job quality index (levels of job control, demands and complexity, insecurity, and perceptions of unfair pay). Analysis was conducted using longitudinal fixed-effects logistic regression models and negative binomial regression models. There was a dose-response relationship between the number of psychosocial job stressors reported by an individual and the odds of paid sickness absence (1 adversity: odds ratio (OR) = 1.26, 95% confidence interval (CI): 1.09, 1.45 (P = 0.002); 2 adversities: OR = 1.28, 95% CI: 1.09, 1.51 (P = 0.002); ≥3 adversities: OR = 1.58, 95% CI: 1.29, 1.94 (P job quality. These results suggest that workplace interventions aiming to improve the quality of work could help reduce sickness absence. © The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Lp-PLA2 activity is associated with increased risk of diabetic retinopathy: a longitudinal disease progression study.

    Science.gov (United States)

    Siddiqui, Moneeza K; Kennedy, Gwen; Carr, Fiona; Doney, Alexander S F; Pearson, Ewan R; Morris, Andrew D; Johnson, Toby; McLaughlin, Megan M; Williams, Rachel E; Palmer, Colin N A

    2018-06-01

    The aim of the study was to examine the association between lipoprotein-associated phospholipase A 2 (Lp-PLA 2 ) activity levels and incident diabetic retinopathy and change in retinopathy grade. This was a cohort study of diabetic participants with serum collected at baseline and routinely collected diabetic retinal screening data. Participants with type 2 diabetes from the GoDARTS (Genetics of Diabetes Audit and Research in Tayside Scotland) cohort were used. This cohort is composed of individuals of white Scottish ancestry from the Tayside region of Scotland. Survival analysis accounting for informative censoring by modelling death as a competing risk was performed for the development of incident diabetic retinopathy from a disease-free state in a 3 year follow-up period (n = 1364) by stratified Lp-PLA 2 activity levels (in quartiles). The same analysis was performed for transitions to more severe grades. The hazard of developing incident diabetic retinopathy was 2.08 times higher (95% CI 1.64, 2.63) for the highest quartile of Lp-PLA 2 activity compared with the lowest. Higher Lp-PLA 2 activity levels were associated with a significantly increased risk for transitions to all grades. The hazards of developing observable (or more severe) and referable (or more severe) retinopathy were 2.82 (95% CI 1.71, 4.65) and 1.87 (95% CI 1.26, 2.77) times higher for the highest quartile of Lp-PLA 2 activity compared with the lowest, respectively. Higher Lp-PLA 2 levels are associated with increased risk of death and the development of incident diabetic retinopathy, as well as transitions to more severe grades of diabetic retinopathy. These associations are independent of calculated LDL-cholesterol and other traditional risk factors. Further, this biomarker study shows that the association is temporally sensitive to the proximity of the event to measurement of Lp-PLA 2.

  12. Association between Periodontal disease and Prostate cancer: Results of a 12-year Longitudinal Cohort Study in South Korea

    Science.gov (United States)

    Lee, Jae-Hong; Kweon, Helen Hye-In; Choi, Jung-Kyu; Kim, Young-Taek; Choi, Seong-Ho

    2017-01-01

    The incidence of prostate cancer (PC) accompanying periodontal disease (PD) is anticipated to increase due to population aging. The aim of this study was to determine the association between PD and PC using data in the National Health Insurance Service-Health Examinee Cohort (NHIS-HEC). A random stratified sample of 187,934 South Koreans was collected from the NHIS database from 2002 to 2013. We assessed the relationship between PD and PC while adjusting for potential confounding factors (sex, age, household income, insurance status, residence area, hypertension, diabetes mellitus, cerebral infarction, angina pectoris, myocardial infarction, smoking status, alcohol intake, and regular exercise). The overall incidence of PC with PD among those aged 40 years and older was 0.28% (n = 531). In the multivariate Cox proportional-hazard regression analysis with adjustment for confounding factors, PD was associated with a 14% higher risk of PC (HR = 1.14, 95% CI = 1.01-1.31, P = 0.042). The findings of this study suggest that PD is significantly and positively associated with PC. Further studies are required to identify the mechanisms underlying the links between PD and PC. PMID:28928887

  13. Studies of generalized elemental imbalances in neurological disease patients using INAA [instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Ehmann, W.D.; Vance, D.E.; Khare, S.S.; Kasarskis, E.J.; Markesbery, W.R.

    1988-01-01

    Evidence has been presented in the literature to implicate trace elements in the etiology of several age-related neurological diseases. Most of these studies are based on brain analyses. Using instrumental neutron activation analysis (INAA), we have observed trace element imbalances in brains of patients with Alzheimer's disease, amyotrophic lateral sclerosis (ALS), and Picks's disease. The most prevalent elemental imbalances found in the brain were for bromine, mercury, and the alkali metals. In this study the authors report INAA studies of trace elements in nonneural tissues from Alzheimer's disease and ALS patients. Samples from household relatives were collected for use as controls wherever possible. Hair samples were washed according to the International Atomic Energy Agency recommended procedure. Fingernail samples were scraped with a quartz knife prior to washing by the same procedure. For ALS patients, blood samples were also collected. These data indicate that elemental imbalances in Alzheimer's disease and ALS are not restricted to the brain. Many elements perturbed in the brain are also altered in the several nonneural tissues examined to date. The imbalances in different tissues, however, are not always in the same direction. The changes observed may represent causes, effects, or simply epiphenomena. Longitudinal studies of nonneural tissues and blood, as well as tissue microprobe analyses at the cellular and subcellular level, will be required in order to better assess the role of trace elements in the etiology of these diseases

  14. Longitudinal analysis of hearing loss in a case of hemosiderosis of the central nervous system

    NARCIS (Netherlands)

    Weekamp, H H; Huygen, P L M; Merx, J L; Kremer, H P H; Cremers, Cor W R J; Longridge, Neil S

    OBJECTIVE: To describe cochleovestibular aspects of superficial hemosiderosis of the central nervous system. BACKGROUND: Superficial hemosiderosis of the central nervous system is a rare disease in which cochleovestibular impairment, cerebellar ataxia, and myelopathy are the most frequent signs.

  15. Longitudinal analysis of hearing loss in a case of hemosiderosis of the central nervous system.

    NARCIS (Netherlands)

    Weekamp, H.; Huygen, P.L.M.; Merx, J.L.; Kremer, H.P.H.; Cremers, C.W.R.J.; Longridge, N.S.

    2003-01-01

    OBJECTIVE: To describe cochleovestibular aspects of superficial hemosiderosis of the central nervous system. BACKGROUND: Superficial hemosiderosis of the central nervous system is a rare disease in which cochleovestibular impairment, cerebellar ataxia, and myelopathy are the most frequent signs.

  16. Long-term effect of coffee consumption on autosomal dominant polycystic kidneys disease progression: results from the Suisse ADPKD, a Prospective Longitudinal Cohort Study.

    Science.gov (United States)

    Girardat-Rotar, Laura; Puhan, Milo A; Braun, Julia; Serra, Andreas L

    2018-02-01

    Previous in vitro experiments of human polycystic kidney disease (PKD) cells reported that caffeine is a risk factor for the promotion of cyst enlargement in patients with autosomal dominant PKD (ADPKD). The relentless progression of ADPKD inclines the majority of physicians to advocate minimization of caffeine consumption despite the absence of clinical data supporting such a recommendation so far. This is the first clinical study to assess prospectively the association between coffee consumption and disease progression in a longitudinal ADPKD cohort. Information on coffee consumption and disease progression was collected at each follow-up visit using standardized measurement methods. The main model for the outcomes, kidney size (height-adjusted total kidney volume, htTKV) and kidney function (estimated glomerular filtration rate, eGFR), was a linear mixed model. Patients entered the on-going Swiss ADPKD study between 2006 and June 2014 and had at least 1 visit every year. The sample size of the study population was 151 with a median follow-up of 4 visits per patient and a median follow-up time of 4.38 years. After multivariate adjustment for age, smoking, hypertension, sex, body mass index and an interaction term (coffee*visit), coffee drinkers did not have a statistically significantly different kidney size compared to non-coffee drinkers (difference of -33.03 cm 3 height adjusted TKV, 95% confidence interval (CI) from -72.41 to 6.34, p = 0.10). After the same adjustment, there was no statistically significant difference in eGFR between coffee and non-coffee drinkers (2.03 ml/min/1.73 m 2 , 95% CI from -0.31 to 4.31, p = 0.089). Data derived from our prospective longitudinal study do not confirm that drinking coffee is a risk factor for ADPKD progression.

  17. Longitudinal analysis of standardized test scores of students in the Science Writing Heuristic approach

    Science.gov (United States)

    Chanlen, Niphon

    The purpose of this study was to examine the longitudinal impacts of the Science Writing Heuristic (SWH) approach on student science achievement measured by the Iowa Test of Basic Skills (ITBS). A number of studies have reported positive impact of an inquiry-based instruction on student achievement, critical thinking skills, reasoning skills, attitude toward science, etc. So far, studies have focused on exploring how an intervention affects student achievement using teacher/researcher-generated measurement. Only a few studies have attempted to explore the long-term impacts of an intervention on student science achievement measured by standardized tests. The students' science and reading ITBS data was collected from 2000 to 2011 from a school district which had adopted the SWH approach as the main approach in science classroom