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991.
Analysis of three-dimensional (3D) images of human torsos for torso deformities such as scoliosis requires classifying torso distortion. Assessing torso distortion from 3D images is not trivial as actual torsos are non-symmetric and show an outstanding range of variations leading to high classification errors. As the degree of spinal deformity (and classification of torso shape) influences scoliosis treatment options, the development of more accurate classification procedures is desirable. This paper presents a technique for assessing torso shape and classifying scoliosis into mild, moderate and severe categories using two indices, 'twist' and 'bend', obtained from orthogonally transformed images of the complete torso surface called orthogonal maps. Four transforms (axial line, unfolded cylinder, enclosing cylinder and subtracting cylinder) were used. Blind tests on 361 computer models with known deformation parameter values show 100% classification accuracy. Tests on eight volunteers without scoliosis validated the system and tests on 22 torso images of volunteers with scoliosis showed up to 95.5% classification accuracy. In addition to classifying scoliosis, orthogonal maps present the entire torso in one view and are viable for use in scoliosis clinics for monitoring the progression of scoliosis. 相似文献
992.
Geoffrey Nelson Joanna Ochocka Rich Janzen John Trainor Paula Goering Jonathan Lomotey 《Journal of community psychology》2007,35(5):655-665
The objective of this study was to evaluate the impacts of participation in mental health Consumer/Survivor Initiatives (CSIs), organizations run by and for people with mental illness. A nonequivalent comparison group design was used to compare three groups of participants: (a) those who were continually active in CSIs over a 36‐month period (n = 25); (b) those who had been active in CSIs at 9‐ and 18‐month follow‐up periods, but who were no longer active at 36 months (n = 35); and (c) a comparison group of participants who were never active in CSIs (n = 42). Data were gathered at baseline, 9‐, 18‐, and 36‐month follow‐ups. The three groups were comparable at baseline on a wide range of demographic variables, self‐reported psychiatric diagnosis, service use, and outcome measures. At 36 months, the continually active participants scored significantly higher than the other two groups of participants on community integration, quality of life (daily living activities), and instrumental role involvement, and significantly lower on symptom distress. No differences between the groups were found on other outcome measures. Improvements in 36‐month outcomes for people with mental illness who participated in CSIs suggest the potential value of these peer support organizations. Further research is needed to determine the replicability of these positive findings. © 2007 Wiley Periodicals, Inc. J Comm Psychol 35: 655–665, 2007. 相似文献
993.
Laura Annaratone Marco Volante Sofia Asioli Nelson Rangel Gianni Bussolati 《Endocrine pathology》2013,24(2):83-91
The aim of this study was to assess the suitability of using real-time quantitative PCR (RT-qPCR) to characterize neuroendocrine (NE) tumors of the pancreas. For a series of tumors, we evaluated several genes of interest, and the data were matched with the “classical” immunohistochemical (IHC) features. In 21 cases, we extracted RNA from formalin-fixed paraffin-embedded (FFPE) blocks, and in nine cases, we also extracted RNA from fresh-frozen tissue. The RT-qPCR procedure was performed using two sets of customized arrays. The test using the first set, covering 96 genes of interest, was focused on assessing the feasibility of the procedure, and the results were used to select 18 genes indicative of NE differentiation, clinical behavior, and therapeutic responsiveness for use in the second set of arrays. Threshold cycle (Ct) values were used to calculate the fold-changes in gene expression using the 2-??Ct method. Statistical procedures were used to analyze the results, which were matched with the IHC and follow-up data. Material from fresh-frozen samples performed better in terms of the level of amplification, but acceptable and concordant results were also obtained from FFPE samples. In addition, high concordance was observed between the mRNA and protein expression levels of somatostatin receptor type 2A (R?=?0.52, p?=?0.016). Genes associated with NE differentiation, as well as the gastrin-releasing peptide receptor and O-6-methylguanine-DNA methyltransferase genes, were underexpressed, whereas angiogenesis-associated markers (CDH13 and SLIT2) were overexpressed in tissues with malignant behavior. The RT-qPCR procedure is practical and feasible in economic terms for the characterization of NE tumors of the pancreas and can complement morphological and IHC-based evaluations. Thus, the results of the RT-qPCR procedure might offer an objective basis for therapeutic choices. 相似文献
994.
James D. Richardson Adam J. Nelson Andrew C. W. Zannettino Stan Gronthos Stephen G. Worthley Peter J. Psaltis 《Stem cell reviews》2013,9(3):281-302
Despite current treatment options, cardiac failure is associated with significant morbidity and mortality highlighting a compelling clinical need for novel therapeutic approaches. Based on promising pre-clinical data, stem cell therapy has been suggested as a possible therapeutic strategy. Of the candidate cell types evaluated, mesenchymal stromal/stem cells (MSCs) have been widely evaluated due to their ease of isolation and ex vivo expansion, potential allogeneic utility and capacity to promote neo-angiogenesis and endogenous cardiac repair. However, the clinical application of MSCs for mainstream cardiovascular use is currently hindered by several important limitations, including suboptimal retention and engraftment and restricted capacity for bona fide cardiomyocyte regeneration. Consequently, this has prompted intense efforts to advance the therapeutic properties of MSCs for cardiovascular disease. In this review, we consider the scope of benefit from traditional plastic adherence-isolated MSCs and the lessons learned from their conventional use in preclinical and clinical studies. Focus is then given to the evolving strategies aimed at optimizing MSC therapy, including discussion of cell-targeted techniques that encompass the preparation, pre-conditioning and manipulation of these cells ex vivo, methods to improve their delivery to the heart and innovative substrate-directed strategies to support their interaction with the host myocardium. 相似文献
995.
Linda Broer Veryan Codd Dale R Nyholt Joris Deelen Massimo Mangino Gonneke Willemsen Eva Albrecht Najaf Amin Marian Beekman Eco J C de Geus Anjali Henders Christopher P Nelson Claire J Steves Margie J Wright Anton J M de Craen Aaron Isaacs Mary Matthews Alireza Moayyeri Grant W Montgomery Ben A Oostra Jacqueline M Vink Tim D Spector P Eline Slagboom Nicholas G Martin Nilesh J Samani Cornelia M van Duijn Dorret I Boomsma 《European journal of human genetics : EJHG》2013,21(10):1163-1168
Telomere length (TL) has been associated with aging and mortality, but individual differences are also influenced by genetic factors, with previous studies reporting heritability estimates ranging from 34 to 82%. Here we investigate the heritability, mode of inheritance and the influence of parental age at birth on TL in six large, independent cohort studies with a total of 19 713 participants. The meta-analysis estimate of TL heritability was 0.70 (95% CI 0.64–0.76) and is based on a pattern of results that is highly similar for twins and other family members. We observed a stronger mother–offspring (r=0.42; P-value=3.60 × 10−61) than father–offspring correlation (r=0.33; P-value=7.01 × 10−5), and a significant positive association with paternal age at offspring birth (β=0.005; P-value=7.01 × 10−5). Interestingly, a significant and quite substantial correlation in TL between spouses (r=0.25; P-value=2.82 × 10−30) was seen, which appeared stronger in older spouse pairs (mean age ≥55 years; r=0.31; P-value=4.27 × 10−23) than in younger pairs (mean age<55 years; r=0.20; P-value=3.24 × 10−10). In summary, we find a high and very consistent heritability estimate for TL, evidence for a maternal inheritance component and a positive association with paternal age. 相似文献
996.
Tiffany L. Sudduth Frederick A. Schmitt Peter T. Nelson Donna M. Wilcock 《Neurobiology of aging》2013
Alzheimer's disease (AD) involves progressive neurodegeneration in the presence of misfolded proteins and poorly-understood inflammatory changes. However, research has shown that AD is genetically, clinically, and pathologically heterogeneous. In frozen brain samples of frontal cortex (diseased) and cerebellum (nondiseased) from the University of Kentucky Alzheimer's Disease Center autopsy cohort, we performed gene expression analysis for genes categorizing inflammatory states (termed M1 and M2) from early and late stage AD, and age-matched nondemented controls. We performed analysis of the serum samples for a profile of inflammatory proteins and examined the neuropathologic data on these samples. Striking heterogeneity was found in early AD. Specifically, early-stage AD brain samples indicated apparent polarization toward either the M1 or M2 brain inflammatory states when compared with age-matched nondisease control tissue. This polarization was observed in the frontal cortex and not in cerebellar tissue. We were able to detect differences in AD neuropathology, and changes in serum proteins that distinguished the individuals with apparent M1 versus M2 brain inflammatory polarization. 相似文献
997.
998.
Mauro Castellarin Katy Milne Thomas Zeng Kane Tse Michael Mayo Yongjun Zhao John R Webb Peter H Watson Brad H Nelson Robert A Holt 《The Journal of pathology》2013,229(4):515-524
High‐grade serous carcinoma (HGSC) is the most common and fatal form of ovarian cancer. While most tumours are highly sensitive to cytoreductive surgery and platinum‐ and taxane‐based chemotherapy, the majority of patients experience recurrence of treatment‐resistant tumours. The clonal origin and mutational adaptations associated with recurrent disease are poorly understood. We performed whole exome sequencing on tumour cells harvested from ascites at three time points (primary, first recurrence, and second recurrence) for three HGSC patients receiving standard treatment. Somatic point mutations and small insertions and deletions were identified by comparison to constitutional DNA. The clonal structure and evolution of tumours were inferred from patterns of mutant allele frequencies. TP53 mutations were predominant in all patients at all time points, consistent with the known founder role of this gene. Tumours from all three patients also harboured mutations associated with cell cycle checkpoint function and Golgi vesicle trafficking. There was convergence of germline and somatic variants within the DNA repair, ECM, cell cycle control, and Golgi vesicle pathways. The vast majority of somatic variants found in recurrent tumours were present in primary tumours. Our findings highlight both known and novel pathways that are commonly mutated in HGSC. Moreover, they provide the first evidence at single nucleotide resolution that recurrent HGSC arises from multiple clones present in the primary tumour with negligible accumulation of new mutations during standard treatment. 相似文献
999.
Y-S. Victor Liu Janice K. Daniels Patricia A. Nelson 《Journal of immunoassay & immunochemistry》2013,34(3-4):335-348
Abstract An enzyme-linked immunosorbent assay on nitrocellulose based microtiter plates for the detection of uncharacterized tumor associated antigens in squamous cell carcinoma and adenocarcinoma cancer patients' sera is described. Nitrocellulose microtiter plates are more sensitive than the plastic plates of polystyrene and polyvinyl chloride for the detection of antigens in serum. Monoclonal antibodies were selected for their net reactivities toward cancer patients' sera as compared to nomal sera. Sera from benign liver and kidney disease patients and activated human peripheral blood leukocyte supernatant were used to reduce potential false positives toward inflammatory and benign diseases. Using this system, fourteen antibodies were selected out of over eight hundred antibodies for their potential serodiagnostic application. 相似文献
1000.
Saeheon Jang Sungwon Jung Chiun Pae Blanchard Portland Kimberly J Craig Nelson Ashwin A. Patkar 《Journal of affective disorders》2013