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61.
Does Bone Resorption Stimulate Periosteal Expansion? A Cross‐Sectional Analysis of β‐C‐telopeptides of Type I Collagen (CTX), Genetic Markers of the RANKL Pathway,and Periosteal Circumference as Measured by pQCT 下载免费PDF全文
John P Kemp Adrian Sayers Lavinia Paternoster David M Evans Kevin Deere Beate St Pourcain Nicholas J Timpson Susan M Ring Mattias Lorentzon Terho Lehtimäki Joel Eriksson Mika Kähönen Olli Raitakari Marika Laaksonen Harri Sievänen Jorma Viikari Leo‐Pekka Lyytikäinen George Davey Smith William D Fraser Liesbeth Vandenput Claes Ohlsson Jon H Tobias 《Journal of bone and mineral research》2014,29(4):1015-1024
We hypothesized that bone resorption acts to increase bone strength through stimulation of periosteal expansion. Hence, we examined whether bone resorption, as reflected by serum β‐C‐telopeptides of type I collagen (CTX), is positively associated with periosteal circumference (PC), in contrast to inverse associations with parameters related to bone remodeling such as cortical bone mineral density (BMDC). CTX and mid‐tibial peripheral quantitative computed tomography (pQCT) scans were available in 1130 adolescents (mean age 15.5 years) from the Avon Longitudinal Study of Parents and Children (ALSPAC). Analyses were adjusted for age, gender, time of sampling, tanner stage, lean mass, fat mass, and height. CTX was positively related to PC (β = 0.19 [0.13, 0.24]) (coefficient = SD change per SD increase in CTX, 95% confidence interval)] but inversely associated with BMDC (β = –0.46 [–0.52,–0.40]) and cortical thickness [β = –0.11 (–0.18, –0.03)]. CTX was positively related to bone strength as reflected by the strength‐strain index (SSI) (β = 0.09 [0.03, 0.14]). To examine the causal nature of this relationship, we then analyzed whether single‐nucleotide polymorphisms (SNPs) within key osteoclast regulatory genes, known to reduce areal/cortical BMD, conversely increase PC. Fifteen such genetic variants within or proximal to genes encoding receptor activator of NF‐κB (RANK), RANK ligand (RANKL), and osteoprotegerin (OPG) were identified by literature search. Six of the 15 alleles that were inversely related to BMD were positively related to CTX (p < 0.05 cut‐off) (n = 2379). Subsequently, we performed a meta‐analysis of associations between these SNPs and PC in ALSPAC (n = 3382), Gothenburg Osteoporosis and Obesity Determinants (GOOD) (n = 938), and the Young Finns Study (YFS) (n = 1558). Five of the 15 alleles that were inversely related to BMD were positively related to PC (p < 0.05 cut‐off). We conclude that despite having lower BMD, individuals with a genetic predisposition to higher bone resorption have greater bone size, suggesting that higher bone resorption is permissive for greater periosteal expansion. © 2014 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. 相似文献
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Raffaele Ferrari Mia Kero Kin Mok Anders Paetau Pentti J. Tienari Olli Tynninen John Hardy Parastoo Momeni Auli Verkkoniemi-Ahola Liisa Myllykangas 《Neurobiology of aging》2014
A hexanucleotide repeat expansion in the chromosome 9 open reading frame 72 gene (C9orf72) was recently identified as the most common genetic cause of frontotemporal dementia/amyotrophic lateral sclerosis. Here we describe the clinical, pathologic, and genetic features of a Finnish C9orf72 expansion carrier, who developed a dysplastic gangliocytoma (Lhermitte-Duclos disease), a rare hamartoma/overgrowth syndrome of cerebellar granule cells associated with mutations in the phosphatase and tensin homolog gene. In addition to the dysplastic gangliocytoma, the patient showed typical transactive response DNA-binding protein with Mr 43 kD (TDP-43) pathology mainly in the cortex and the substantia nigra and numerous p62-positive/TDP-43-negative inclusions in the cerebellar granule cells. His sister carried the same gene defect and showed a similar type of TDP-43/p62 pathology in her brain. Our findings confirm that the clinical and pathologic picture of C9orf72 mutation carriers is more heterogeneous than originally thought and warrants further studies on the possible involvement of phosphatase and tensin homolog gene pathway in the specific cerebellar granule cell pathology associated with C9orf72 expansion. 相似文献
64.
Luz E. Cabrera Constanze Schmotz Moin A. Saleem Sanna Lehtonen Olli Vapalahti Antti Vaheri Satu Mkel Jukka Mustonen Tomas Strandin 《Viruses》2022,14(3)
Old–world orthohantaviruses cause hemorrhagic fever with renal syndrome (HFRS), characterized by acute kidney injury (AKI) with transient proteinuria. It seems plausible that proteinuria during acute HFRS is mediated by the disruption of the glomerular filtration barrier (GFB) due to vascular leakage, a hallmark of orthohantavirus–caused diseases. However, direct infection of endothelial cells by orthohantaviruses does not result in increased endothelial permeability, and alternative explanations for vascular leakage and diminished GFB function are necessary. Vascular integrity is partly dependent on an intact endothelial glycocalyx, which is susceptible to cleavage by heparanase (HPSE). To understand the role of glycocalyx degradation in HFRS–associated proteinuria, we investigated the levels of HPSE in urine and plasma during acute, convalescent and recovery stages of HFRS caused by Puumala orthohantavirus. HPSE levels in urine during acute HFRS were significantly increased and strongly associated with the severity of AKI and other markers of disease severity. Furthermore, increased expression of HPSE was detected in vitro in orthohantavirus–infected podocytes, which line the outer surfaces of glomerular capillaries. Taken together, these findings suggest the local activation of HPSE in the kidneys of orthohantavirus–infected patients with the potential to disrupt the endothelial glycocalyx, leading to increased protein leakage through the GFB, resulting in high amounts of proteinuria. 相似文献
65.
Antibadies against Yersinia,Campylobacter, SalmoneUa,and Chlamydia in patients with Behqet's disease
66.
Urho M. Kujala Jyrki Kettunen Heli Paananen Teuvo Aalto Michele C. Batti Olli Impivaara Tapio Videman Seppo Sarna 《Arthritis \u0026amp; Rheumatology》1995,38(4):539-546
Objective. To determine the relationship between different physical loading conditions and findings of knee osteoarthritis (OA). Methods. We selected 117 male former top-level athletes (age range 45–68 years) who had participated in sports activities with distinctly different loading conditions: 28 had been long-distance runners, 31 soccer players, 29 weight lifters, and 29 shooters. Histories of lifetime occupational and athletic knee loading, knee injuries, and knee symptoms were obtained, and subjects were examined clinically and radiographically for knee findings of OA. Results. The prevalence of tibiofemoral or patellofemoral OA based on radiographic examination was 3% in shooters, 29% in soccer players, 31% in weight lifters, and 14% in runners (P = 0.016 between groups). Soccer players had the highest prevalence of tibiofemoral OA (26%), and weight lifters had the highest prevalence of patellofemoral OA (28%). Subjects with radiographically documented knee OA had more symptoms, clinical findings, and functional limitations than did subjects without knee OA. By stepwise logistic regression analysis, the risk for having knee OA was increased in subjects with previous knee injuries (odds ratio [OR] 4.73), high body mass index at the age of 20 (OR 1.76/unit of increasing body mass index), previous participation in heavy work (OR 1.08/work-year), kneeling or squatting work (OR 1.10/work-year), and in subjects participating in soccer (OR 5.21). Conclusion. Soccer players and weight lifters are at increased risk of developing premature knee OA. The increased risk is explained in part by knee injuries in soccer players and by high body mass in weight lifters. 相似文献
67.
目的:肺癌分期与肿瘤直径的关系已被证实是一个预后指标,因此被纳入1986年肺癌分类的国际系统。近年来由于CT飞速发展,人们可以诊断出更小的肺癌,于是有人提倡对肺癌Ⅰ期进一步分期,即根据肿瘤直径小于还是大于30mm,将无确切远处淋巴结转移的病例(Ⅰ期病例)细分为Ⅰa和Ⅰb期。在诊断无症状(即潜伏)的肺癌时,CT普查的开展使人们考虑肿瘤大小的预后价值。在此我们对CT普查诊断的无症状潜伏型肺癌作了分期与大小关系的报道。 相似文献
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70.
Spatial aspects of oncogenic signalling determine the response to combination therapy in slice explants from Kras‐driven lung tumours 下载免费PDF全文
Katja Närhi Ashwini S Nagaraj Elina Parri Riku Turkki Petra W van Duijn Annabrita Hemmes Jenni Lahtela Virva Uotinen Mikko I Mäyränpää Kaisa Salmenkivi Jari Räsänen Nina Linder Jan Trapman Antti Rannikko Olli Kallioniemi Taija M Af Hällström Johan Lundin Wolfgang Sommergruber Simon Anders Emmy W Verschuren 《The Journal of pathology》2018,245(1):101-113
A key question in precision medicine is how functional heterogeneity in solid tumours informs therapeutic sensitivity. We demonstrate that spatial characteristics of oncogenic signalling and therapy response can be modelled in precision‐cut slices from Kras‐driven non‐small‐cell lung cancer with varying histopathologies. Unexpectedly, profiling of in situ tumours demonstrated that signalling stratifies mostly according to histopathology, showing enhanced AKT and SRC activity in adenosquamous carcinoma, and mitogen‐activated protein kinase (MAPK) activity in adenocarcinoma. In addition, high intertumour and intratumour variability was detected, particularly of MAPK and mammalian target of rapamycin (mTOR) complex 1 activity. Using short‐term treatment of slice explants, we showed that cytotoxic responses to combination MAPK and phosphoinositide 3‐kinase–mTOR inhibition correlate with the spatially defined activities of both pathways. Thus, whereas genetic drivers determine histopathology spectra, histopathology‐associated and spatially variable signalling activities determine drug sensitivity. Our study is in support of spatial aspects of signalling heterogeneity being considered in clinical diagnostic settings, particularly to guide the selection of drug combinations. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. 相似文献