scholarly journals Human Bone Proteomes before and after Decomposition: Investigating the Effects of Biological Variation and Taphonomic Alteration on Bone Protein Profiles and the Implications for Forensic Proteomics

2021 ◽  
Author(s):  
Hayley L. Mickleburgh ◽  
Edward C. Schwalbe ◽  
Andrea Bonicelli ◽  
Haruka Mizukami ◽  
Federica Sellitto ◽  
...  
Keyword(s):  
Biological Variation ◽  
Human Bone ◽  
Protein Profiles ◽  
Before And After

Assessment of the Biological Variation of Plasma Tissue Inhibitor of Metalloproteinases-1

2008 ◽  
Vol 23 (1) ◽  
pp. 42-47 ◽  
Author(s):  
C.B. Frederiksen ◽  
A.F. Lomholt ◽  
T. Lottenburger ◽  
G.J. Davis ◽  
B.L. Dowell ◽  
...  
Keyword(s):  
Physical Exercise ◽  
Intraclass Correlation ◽  
Circadian Variation ◽  
Biological Variation ◽  
Elisa Assay ◽  
Tissue Inhibitor Of Metalloproteinases ◽  
Tissue Inhibitor ◽  
Global Test ◽  
Before And After ◽  
Analytical Variation

Background Tissue inhibitor of metalloproteinases-1 (TIMP-1) measurements in plasma may be useful for the early detection and prognosis of colorectal cancer (CRC). Data on analytical performance and normal intra- and interindividual biological variation are required in order to interpret the utility of TIMP-1 in CRC. The aim of this study was to establish the biological and analytical variation of plasma TIMP-1 in volunteers. Material and methods Three separate studies were undertaken. 1: Plasma was collected from 23 volunteers 6 times within a 3-week period, first in September 2004 (round [R] 1), then repeated in May 2005 (R2) and May 2006 (R3) in the same group of individuals. TIMP-1 levels were determined by the MAC15 ELISA assay and with the Abbott ARCHITECT i2000 Immunoanalyzer. 2: Circadian variation was evaluated in plasma collected 7 times within a 24-hour period (n=16). 3: Effects of physical exercise were evaluated in plasma collected before and after bicycling (n=14). In studies 2 and 3 TIMP-1 levels were determined with the MAC15 ELISA assay only. Results A significant correlation between TIMP-1 MAC15 and ARCHITECT i2000 was shown (rs=0.78, p<0.002), with consistently higher levels being detected by the ARCHITECT i2000. Median levels of TIMP-1 (ARCHITECT) at 8 a.m. in each round were 74.9 ng/mL (range 65.7–89.9) (R1), 87.3 ng/mL (range 72.7–127.9) (R2), and 81.9 ng/mL (range 66.8–113.6) (R3). The within-subject variation was 10.7%, the variation between rounds was 7.4%, and the intraclass correlation was 46.2%. Comparison between the 3 rounds and time of collection showed that TIMP-1 values decreased by 11% after storage for more than 16 months (p=0.0002). A systematic circadian variation in plasma TIMP-1 levels was not observed (p=0.17). No significant variation of plasma TIMP-1 was found in relation to physical exercise (p=0.92 [global test]). Conclusion Levels of plasma TIMP-1 in volunteers show limited circadian, day-to-day, week-to-week and season-to-season variation. In addition, physical exercise has no impact on plasma TIMP-1 levels. Possible storage-dependent decreases in plasma TIMP-1 levels warrant further investigation.

Application of the CLSI EP15-A3 Guideline as an Alternative Troubleshooting Tool for Verification of Assay Precision

2019 ◽  
Vol 152 (Supplement_1) ◽  
pp. S88-S88
Author(s):  
Jose Jara Aguirre ◽  
Karl Ness ◽  
Alicia Algeciras-Schimnich
Keyword(s):  
Quality Control ◽  
Carcinoembryonic Antigen ◽  
Laboratory Investigation ◽  
Analysis Of Variance ◽  
Experimental Approach ◽  
Biological Variation ◽  
Analytical Performance ◽  
Microsoft Excel ◽  
Before And After ◽  
Assay Precision

Abstract Introduction The CLSI EP15-A3 guideline “User Verification of Precision and Estimation of Bias” provides a simple experimental approach to estimate a method’s imprecision and bias. The objective is to determine if the laboratory precision performance of repeatability (SR) and within-laboratory imprecision (SWL) are in accordance to the manufacturer specification claims (MSCs). Objectives Evaluate the utility of the EP15-A3 protocol to verify method precision during a troubleshooting investigation and after major instrument maintenance, using a carcinoembryonic antigen (CEA) immunoassay as an example. Methods CEA was performed on the Beckman Coulter DxI (Beckman Coulter, Brea, CA). Quality control (QC) levels (L1: 2.89; L2: 21.10; L3: 39.10 ng/mL) (Bio-Rad Laboratories, Irvine, CA) were used. Each QC level was measured before and after instrument maintenance as follows: five replicates per run, one run per day, and during 5 days. Imprecision estimates (IEs) for SR (%CVR) and SWL (%CVWL) were calculated by one-way analysis of variance using Microsoft Excel Analyse-it software. Estimated imprecision was compared to MSC and desirable imprecision specifications based on biological variation (BV). Results A change in the analytical performance of CEA was detected by a decreased sigma-metric indicator. After a bias problem was ruled out, the observed %CVR for L1, L2, and L3 were 7.2%, 3.7%, and 4.8%, respectively. The %CVWL were 8.3%, 5.0%, and 5.5%, which exceeded the MSC of %CVWL~4.0% to 4.5%. After a laboratory investigation, major instrument maintenance was performed by the manufacturer. The %CVR and %CVWL estimates for L1, L2, and L3 after maintenance were 3.2%, 3.8%, 3.5% and 3.9%, 4.2%, 4.0%, respectively. After maintenance, the CEA performance was consistent with the MSC for each of the levels analyzed and within the BV impression goal of %CV ≤6.4. Conclusion CLSI EP15-A3 guideline is an alternative troubleshooting tool that can be used to investigate and verify method precision performance before and after significant instrument maintenance.

Effect of Ion-Exchange Adsorption on the Protein Profiles of White Wines

2001 ◽  
Vol 7 (3) ◽  
pp. 217-224 ◽  
Author(s):  
M. R. Sarmento ◽  
J. C. Oliveiraz ◽  
M. Slatner ◽  
R. B. Boulton
Keyword(s):  
Ion Exchange ◽  
Euclidean Distance ◽  
Protein Profiles ◽  
Protein Peak ◽  
Profile Similarity ◽  
Two Samples ◽  
Before And After ◽  
Exchange Adsorption ◽  
Peak Areas ◽  
Hplc Fractionation

The protein profiles of two different wines of Austrian and Portuguese origin, characterized by HPLC fractionation, were compared before and after ion-exchange adsorption of the wine proteins. Conventionally used sodium bentonite and three alternative nonswelling commercial resins were used. Profile similarity was assessed in terms of the Euclidean distance of all protein peak areas for two samples, and of the average of the differences between each protein peak percentile area between two samples. In general, the differences between profiles for the same material increased with the amount of wine adsorbed, showing that some protein fractions were more easily adsorbed than others. Differences between the adsorption with bentonite or with the alternative adsorbents were not statistically significant, with the exception of one adsorbent in one of the wines, where protein removal was more extensive.

Comparison of selected properties of cements modified with glassy carbon and cancellous bone

2020 ◽  
Vol 1 (105) ◽  
pp. 31-41
Author(s):  
P. Choryłek
Keyword(s):  
Bone Cement ◽  
Glassy Carbon ◽  
Reference Sample ◽  
Surface Profile ◽  
Human Bone ◽  
Compression Tests ◽  
Hardness Tests ◽  
Before And After ◽  
Human Body Temperature ◽  
Positive Effect

Purpose: The aim of this manuscript was to study and analyse the properties of bone cement (VertaPlex) before and after modification with glassy carbon (Alfa Aesar) and human bone (MaxGraft). Design/methodology/approach: To achieve the assumed goal, a series of samples was made - five samples for each mixture, where: 5 bone cement samples, 5 bone cement samples mixed with 20-50 μm glassy carbon in the ratio of 1 g carbon per 40 g of cement, and 5 samples of bone cement mixed with 20-50 μm glassy carbon and human bone in the ratio of 1 g of carbon per 40 g of cement and 0.4 g of bone per 40 g of cement. The produced samples (4 for each mixture, 1 was the reference sample) were subjected to tests - compression test, microscopic observations with a 3D microscope, surface profile tests and hardness tests. Findings: The study has shown that modifications with glassy carbon and bone change the mechanical properties, as well as the strength of the samples. Compression tests have shown that the material without admixtures is characterized by the highest compressive strength and the doping of the glassy carbon itself makes the material more brittle. A significant increase in hardness was also observed for samples with glassy carbon and bones after the pressing process. Practical implications: The study was made synthetically, without taking into account the effect of the environment of body fluids and the human body temperature. This study is an introduction to further considerations where samples for which these conditions will be applied are currently being prepared. Originality/value: For commercial use, in treatment of patients, cements modified with glassy carbon and bone glassy carbon have not been used so far. Due to the prerequisites of a positive effect of glassy carbon addition on osseointegration and biocompatibility, the study in this area has been undertaken.

Application of a method for correcting an observed regression between change and initial value for the bias caused by random errors in the initial value.

1977 ◽  
Vol 23 (10) ◽  
pp. 1845-1848 ◽  
Author(s):  
N Blomqvist ◽  
G Cederblad ◽  
K Korsan-Bengtsen ◽  
S Wallerstedt
Keyword(s):  
Blood Coagulation ◽  
Plasma Protein ◽  
Coagulation Factor ◽  
Biological Variation ◽  
Random Errors ◽  
Initial Value ◽  
Before And After

Abstract When studying the correlation between the change of a variable during treatment and the value before treatment, random errors (errors of measurement as well as intra-individual biological variation) may yield seriously biased results. In the present work a method to adjust for this bias is presented. The method was applied to data from blood coagulation factor and plasma protein analyses in chronic alcoholics before and after one week of abstinence. It was found that many of the significant correlations were lost when the data were adjusted.

Xenogeneic Transplantation of Human Bone Sarcomas before and after Preoperative Chemotherapy1

2015 ◽  
pp. 316-320
Author(s):  
P. Groscurth ◽  
L. Huizink ◽  
M. Cserhati ◽  
A. von Hochstetter ◽  
V. Hofmann ◽  
...  
Keyword(s):  
Human Bone ◽  
Xenogeneic Transplantation ◽  
Before And After ◽  
Bone Sarcomas

Comparative Serum Protein Profiles in IPF Patients Before and After Nintedanib Therapy

2019 ◽  
Author(s):  
E. Bargagli ◽  
L. Bergantini ◽  
P. Cameli ◽  
M. D'alessandro ◽  
L. Bini ◽  
...  
Keyword(s):  
Serum Protein ◽  
Protein Profiles ◽  
Before And After

Deformation Replication

1970 ◽  
Vol 28 ◽  
pp. 280-281
Author(s):  
J. Temple Black
Keyword(s):  
Cutting Speed ◽  
Machining Process ◽  
Depth Of Cut ◽  
Rake Face ◽  
Orthogonal Machining ◽  
Aluminum Chips ◽  
Before And After ◽  
Materials Used ◽  
Glass Knife ◽  
Very High

Tool materials used in ultramicrotomy are glass, developed by Latta and Hartmann (1) and diamond, introduced by Fernandez-Moran (2). While diamonds produce more good sections per knife edge than glass, they are expensive; require careful mounting and handling; and are time consuming to clean before and after usage, purchase from vendors (3-6 months waiting time), and regrind. Glass offers an easily accessible, inexpensive material ($0.04 per knife) with very high compressive strength (3) that can be employed in microtomy of metals (4) as well as biological materials. When the orthogonal machining process is being studied, glass offers additional advantages. Sections of metal or plastic can be dried down on the rake face, coated with Au-Pd, and examined directly in the SEM with no additional handling (5). Figure 1 shows aluminum chips microtomed with a 75° glass knife at a cutting speed of 1 mm/sec with a depth of cut of 1000 Å lying on the rake face of the knife.

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