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91.
Verhoeven VJ Hysi PG Saw SM Vitart V Mirshahi A Guggenheim JA Cotch MF Yamashiro K Baird PN Mackey DA Wojciechowski R Ikram MK Hewitt AW Duggal P Janmahasatian S Khor CC Fan Q Zhou X Young TL Tai ES Goh LK Li YJ Aung T Vithana E Teo YY Tay W Sim X Rudan I Hayward C Wright AF Polasek O Campbell H Wilson JF Fleck BW Nakata I Yoshimura N Yamada R Matsuda F Ohno-Matsui K Nag A McMahon G Pourcain BS Lu Y Rahi JS Cumberland PM Bhattacharya S Simpson CL Atwood LD Li X Raffel LJ Murgia F Portas L 《Human genetics》2012,131(9):1467-1480
Myopia is a complex genetic disorder and a common cause of visual impairment among working age adults. Genome-wide association studies have identified susceptibility loci on chromosomes 15q14 and 15q25 in Caucasian populations of European ancestry. Here, we present a confirmation and meta-analysis study in which we assessed whether these two loci are also associated with myopia in other populations. The study population comprised 31 cohorts from the Consortium of Refractive Error and Myopia (CREAM) representing 4 different continents with 55,177 individuals; 42,845 Caucasians and 12,332 Asians. We performed a meta-analysis of 14 single nucleotide polymorphisms (SNPs) on 15q14 and 5 SNPs on 15q25 using linear regression analysis with spherical equivalent as a quantitative outcome, adjusted for age and sex. We calculated the odds ratio (OR) of myopia versus hyperopia for carriers of the top-SNP alleles using a fixed effects meta-analysis. At locus 15q14, all SNPs were significantly replicated, with the lowest P value 3.87?×?10(-12) for SNP rs634990 in Caucasians, and 9.65?×?10(-4) for rs8032019 in Asians. The overall meta-analysis provided P value 9.20?×?10(-23) for the top SNP rs634990. The risk of myopia versus hyperopia was OR 1.88 (95?% CI 1.64, 2.16, P?0.001) for homozygous carriers of the risk allele at the top SNP rs634990, and OR 1.33 (95?% CI 1.19, 1.49, P?0.001) for heterozygous carriers. SNPs at locus 15q25 did not replicate significantly (P value 5.81?×?10(-2) for top SNP rs939661). We conclude that common variants at chromosome 15q14 influence susceptibility for myopia in Caucasian and Asian populations world-wide. 相似文献
92.
Nakhjavani M Morteza A Asgarani F Khalilzadeh O Ghazizadeh Z Bathaie SZ Esteghamati A 《Gene》2012,498(1):107-111
Background
Experimental evidence suggests that heat shock proteins (HSP) and asymmetric dimethylarginine (ADMA) are induced in the state of chronic inflammation and stress conditions. They are both inhibitors of nitric oxide synthase (NOS). The aim of this study was to evaluate the correlation between ADMA and HSP70, in patients with type 2 diabetes with respect to serum levels of C reactive protein (CRP).Methods
We quantified serum HSP70, ADMA and CRP in 80 newly-diagnosed patients with type 2 diabetes plus 80 age-, sex and BMI-matched healthy controls. The patients and controls were also stratified into groups of high and low CRP levels (cut-point: 2.5 mg/ml).Results
Patients with type 2 diabetes had significantly higher serum HSP70 (0.52 [0.51–0.66] vs. 0.27 [0.26–0.36], p < 0.001), ADMA (0.86 [0.81–0.92] vs. 0.72 [0.71–0.85], p < 0.05) and CRP (2.9 [1.7–3.4] vs. 1.6[1.2–2.3], p < 0.05) compared with healthy controls. Serum HSP70 and ADMA levels were significantly correlated in patients with high CRP levels (r = 0.89, p < 0.01), whereas there were no correlation in patients with low CRP (r = − 0.37, p = 0.07) and controls. This correlation was significant (r = 0.77, p < 0.001) in patients with high CRP and also in patients with low CRP levels (r = − 0.51, p < 0.05), after multiple adjustments for LDL and HDL levels.Discussion
We showed that, in a state of high inflammation; serum levels of ADMA parallel the HSP70 levels. However in low inflammation, they are negatively correlated. The duality in HSP70 and ADMA correlation may be related to the duality of NOS function in low and high CRP levels. 相似文献93.
94.
95.
Computational simulation of internal bone remodelling around dental implants: a sensitivity analysis
Hasan I Rahimi A Keilig L Brinkmann KT Bourauel C 《Computer methods in biomechanics and biomedical engineering》2012,15(8):807-814
This study aimed to predict the distribution of bone trabeculae, as a density change per unit time, around a dental implant based on applying a selected mathematical remodelling model. The apparent bone density change as a function of the mechanical stimulus was the base of the applied remodelling model that describes disuse and overload bone resorption. The simulation was tested in a finite element model of a screw-shaped dental implant in an idealised bone segment. The sensitivity of the simulation to different mechanical parameters was investigated; these included element edge length, boundary conditions, as well as direction and magnitude of the implant loads. The alteration in the mechanical parameters had a significant influence on density distribution and model stability, in particular at the cortical bone region. The remodelling model could succeed to achieve trabeculae-like structure around osseointegrated dental implants. The validation of this model to a real clinical case is required. 相似文献
96.
M Noureddini J Verdi SA Mortazavi-Tabatabaei S Sharif A Azimi P Keyhanvar A Shoae-Hassani 《Cell biology international》2012,36(10):961-966
The potential of cell therapy is promising in nerve regeneration, but is limited by ethical considerations about the proper and technically safe source of stem cells. We report the successful differentiation of human EnSCs (endometrial stem cells) as a rich source of renewable and safe progenitors into high-efficiency cholinergic neurons. The extracellular signals of NGF (nerve growth factor) and bFGF (basic fibroblast growth factor) could induce cholinergic neuron differentiation. ChAT (choline acetyltransferase), MAP2 (microtubule associated protein 2) and NF-l (neurofilament L) increased after administration of bFGF and NGF to the EnSC cultures. trkC and FGFR2 (fibroblast growth factor receptor 2), which belong to the NGF and bFGF receptors respectively, were determined in populations of EnSCs. NGF, bFGF and their combination differentially influenced human EnSCs high efficiency differentiation. By inducing cholinergic neurons from EnSCs in a chemically defined medium, we could produce human neural cells without resorting to primary culture of neurons. This in vitro method provides an unlimited source of human neural cells and facilitates clinical applications of EnSCs for neurological diseases. 相似文献
97.
A Fallah EA Akl S Ebrahim GM Ibrahim A Mansouri CJ Foote Y Zhang MG Fehlings 《PloS one》2012,7(8):e43407
Objective
To estimate the effectiveness of anterior cervical discectomy with arthroplasty (ACDA) compared to anterior cervical discectomy with fusion (ACDF) for patient-important outcomes for single-level cervical spondylosis.Data sources
Electronic databases (MEDLINE, EMBASE, Cochrane Register for Randomized Controlled Trials, BIOSIS and LILACS), archives of spine meetings and bibliographies of relevant articles.Study selection
We included RCTs of ACDF versus ACDA in adult patients with single-level cervical spondylosis reporting at least one of the following outcomes: functionality, neurological success, neck pain, arm pain, quality of life, surgery for adjacent level degeneration (ALD), reoperation and dysphonia/dysphagia. We used no language restrictions. We performed title and abstract screening and full text screening independently and in duplicate.Data synthesis
We used random-effects model to pool data using mean difference (MD) for continuous outcomes and relative risk (RR) for dichotomous outcomes. We used GRADE to evaluate the quality of evidence for each outcome.Results
Of 2804 citations, 9 articles reporting on 9 trials (1778 participants) were eligible. ACDA is associated with a clinically significant lower incidence of neurologic failure (RR = 0.53, 95% CI = 0.37–0.75, p = 0.0004) and improvement in the Neck pain visual analogue scale (VAS) (MD = 6.56, 95% CI = 3.22–9.90, p = 0.0001; Minimal clinically important difference (MCID) = 2.5. ACDA is associated with a statistically but not clinically significant improvement in Arm pain VAS and SF-36 physical component summary. ACDA is associated with non-statistically significant higher improvement in the Neck Disability Index Score and lower incidence of ALD requiring surgery, reoperation, and dysphagia/dysphonia.Conclusions
There is no strong evidence to support the routine use of ACDA over ACDF in single-level cervical spondylosis. Current trials lack long-term data required to assess safety as well as surgery for ALD. We suggest that ACDA in patients with single level cervical spondylosis is an option although its benefits and indication over ACDF remain in question. 相似文献98.
99.
Makoto Sasaki Paul Jordan Tomas Welbourne Alireza Minagar Takashi Joh Makoto Itoh John W Elrod J Steven Alexander 《BMC physiology》2005,5(1):3
Background
Cytokine mediated induction of the mucosal addressin cell adhesion molecule-1(MAdCAM-1) expression is associated with the onset and progression of inflammatory bowel disease (IBD). 相似文献100.
Mohammad Houshmand Teresa Mortera Blanco Paola Circosta Narjes Yazdi Alireza Kazemi Giuseppe Saglio Mahin Nikougoftar Zarif 《World journal of stem cells》2019,11(8):476-490
Bone marrow microenvironment(BMM) is the main sanctuary of leukemic stem cells(LSCs) and protects these cells against conventional therapies. However, it may open up an opportunity to target LSCs by breaking the close connection between LSCs and the BMM. The elimination of LSCs is of high importance, since they follow cancer stem cell theory as a part of this population. Based on cancer stem cell theory, a cell with stem cell-like features stands at the apex of the hierarchy and produces a heterogeneous population and governs the disease.Secretion of cytokines, chemokines, and extracellular vesicles, whether through autocrine or paracrine mechanisms by activation of downstream signaling pathways in LSCs, favors their persistence and makes the BMM less hospitable for normal stem cells. While all details about the interactions of the BMM and LSCs remain to be elucidated, some clinical trials have been designed to limit these reciprocal interactions to cure leukemia more effectively. In this review, we focus on chronic myeloid leukemia and acute myeloid leukemia LSCs and their milieu in the bone marrow, how to segregate them from the normal compartment, and finally the possible ways to eliminate these cells. 相似文献