METHOD COMPARISON STUDIES IN MEDICINE

2013 ◽  
Vol 16 (1) ◽  
pp. 16-22
Author(s):  
Rafdzah Z ◽  
Bulgiba A ◽  
Ismail NA
Keyword(s):  
2011 ◽  
Vol 8 (1) ◽  
Author(s):  
Wen-ying Sylvia Chou ◽  
Paul Han ◽  
Alison Pilsner ◽  
Kisha Coa ◽  
Larrie Greenberg ◽  
...  

Author(s):  
Ye Yang ◽  
Suiyang Liao ◽  
Zhi Luo ◽  
Runzhang Qi ◽  
Niamh Mac Fhionnlaoich ◽  
...  

Accurate nanoparticle (NP) size determination is essential across research domains, with many functions in nanoscience and biomedical research being size-dependent. Although transmission electron microscopy (TEM) is capable of resolving a single NP down to the sub-nm scale, the reliable representation of entire populations is plagued by challenges in providing statistical significance, predominantly due to limited sample counts, suboptimal preparation procedures and operator bias during image acquisition and analysis. Meanwhile alternative techniques exist, but reliable implementation requires a detailed understanding of appendant limitations. Herein, conventional TEM is compared to the size determination of sub-10 nm gold NPs in solution by small-angle X-ray scattering and analytical ultracentrifugation. Form-free Monte Carlo fitting of scattering profiles offers access to a direct representation of the core size distribution while ultracentrifugation sedimentation velocity analysis provides information of the hydrodynamic size distribution. We report a comparison of these three methods in determining the size of quasi-monodisperse, polydisperse and bimodal gold nanoparticles of 2 – 7 nm and discuss advantages and limitations of each technique.


2020 ◽  
Vol 17 ◽  
Author(s):  
Zhiping Jiang ◽  
Zhizhang Tian ◽  
Chuntao Zhang ◽  
Dengke Li ◽  
Ruoxin Wu ◽  
...  

Background: Speciation analysis is defined as the analytical activities of identifying and/or measuring the quantities of one or more individual chemical species in a sample. The knowledge of elemental species provides more complete information about mobility, bioavailability and the impact of elements on ecological systems or biological organisms. It is no longer sufficient to quantitate the total elemental content of samples to define toxicity or essentiality. Thus speciation analysis is of vital importance and generally offers a better understanding of a specific element. Discussion: Thorough speciation scheme consisting of sampling, sample preparation, species analysis and evaluation were described. Special emphasis is placed on recent speciation analysis approaches including both direct and coupling methods. A current summary of advantages and limitations of the various methods as well as an illustrative method comparison are presented. Certain elements and species of interest are briefly mentioned and practical examples of speciation applications in tobacco and other important economic crops are also discussed. Aim/Conclusion: This review aims to offer comprehensive knowledge about elemental speciation and provide readers with valuable information. Many strategies have been developed for the determination of multiple elemental species in tobacco and other important economic crops. Nevertheless, it is an eternal pursuit to establish speciation methods which can balance accuracy, agility as well as universality.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1598.3-1598
Author(s):  
K. Romanowska-Prochnicka ◽  
A. Wajda ◽  
A. Paradowska-Gorycka ◽  
A. Felis-Giemza ◽  
E. Walczuk ◽  
...  

Background:PDGF is a potential important factor in the pathogenesis of scleroderma. PDGF is almost undetectable in healthy skin or lung. Immunohistochemical studies have revealed increased presence of PDGFαand PDGFβreceptors in scleroderma skin biopsies.Objectives:The aim of this study was to determine the mRNA level ofIFNα1,IL-4, TGFβ1,TGFβ2,PDGFα,PDGFβ,TNFαin whole blood in SSc patients in the aspect of clinicalMethods:A group of 14 patients (50% were women) with systemic sclerosis based on EULAR / ACR 2013 criteria was included in the study. The modified Rodnan Skin Score (mRSS) was evaluated by same assistant at the beginning of the study and six months later. DLCO, HRCT, echocardiography and NFC were measured.Gene expression was determined using validated TaqMan probes in qPCR. Constitutive mRNA level of selected genes was analyzed using ΔCt method. Comparison between different groups of patients was determined using non-parametric Mann-Whitney U test. Correlation was analyzed using non-parametric Spearman test.Results:The mean age of the patients was 60 ± 15.66. 100% of patients had organ involvement as pulmonary fibrosis. 78% - had active changes -features of ground glass.64% of patients had mild mRSS-1-10 skin involvement, 36% had moderate to severe skin involvement. In SSc patientsTGFβ1andIFNα1revealed the highest level of expression in comparison to other analyzed genes. Additionally, very high and significant correlation betweenTNFαandTGFβ1(r=0.7 p=0.004) has been noted. High and significant correlation between mRNAPDGFβandTNFαlevels have been observed. We did not reveal significant differences in analyzed genes expression when compare limited and diffuse SSc. Nevertheless, patients with dSSc were characterized by higher level ofIFNα1(almost 2 times) andTGFβ1. On the border of significance higherPDGFαmRNA level was observed in dSSc patients when compared to lSSc. AveragePDGFαexpression is higher in SSc patients with Scl70 positive than than in patients without Scl70 (p=0.04).In the aspect of clinical parameters, patients with ESR ≤12 mm/h revealed almost 6 times higher level ofIFNα1(p=0.01) in comparison to the patient with ESR>12mm/h.Patients with mRSS above10 points revealed significantly higher ofPDGFαexpression in comparison to patients with mRSS ≤10 (p=0.04). In these group of patients CRP and ESR were not different significantly.In the case of patients with active fibrosis (ground glass) in HRCTIFNα1expression was almost 2.5-times higher than in patients with HRCT non-active. Significantly higherPDGFα has been revealed in patients with active HRCT when compared with patient with non-active HRCT. Nevertheless these two groups did not differ in ESR or OB parameter.SSc patients in active phase of NFC revealed almost 3 times higher level ofIFNα1expression in comparison with the patient in late phase.Conclusion:The mRNA level ofPDGFαmay be a potential blood marker to predict worse prognosis in sclerodermaReferences:[1]Rheumatology (Oxford). 2008 Oct;47 Suppl 5:v2-4. doi: 10.1093/rheumatology/ken265.Role of PDGF in fibrotic diseases and systemic sclerosis.Trojanowska M1.Acknowledgments:NoDisclosure of Interests:None declared


JIMD Reports ◽  
2021 ◽  
Author(s):  
Komalben Parmar ◽  
Maua Mosha ◽  
David A. Weinstein ◽  
Rebecca Riba‐Wolman

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