scholarly journals HMGB1 concentration measurements in trauma patients: assessment of pre-analytical conditions and sample material

2019 ◽  
Vol 26 (1) ◽  
Author(s):  
William Ottestad ◽  
Ingrid N. Rognes ◽  
Erlend Skaga ◽  
Cassandra Frisvoll ◽  
Guttorm Haraldsen ◽  
...  

Abstract Background HMGB1 is a mediator of systemic inflammation in sepsis and trauma, and a promising biomarker in many diseases. There is currently no standard operating procedure for pre-analytical handling of HMGB1 samples, despite that pre-analytical conditions account for a substantial part of the overall error rate in laboratory testing. We hypothesized that the considerable variations in reported HMGB1 concentrations and kinetics in trauma patients could be partly explained by differences in pre-analytical conditions and choice of sample material. Methods Trauma patients (n = 21) admitted to a Norwegian Level I trauma center were prospectively included. Blood was drawn in K2EDTA coated tubes and serum tubes. The effects of delayed centrifugation were evaluated in samples stored at room temperature for 15 min, 3, 6, 12, and 24 h respectively. Plasma samples subjected to long-term storage in − 80 °C and to repeated freeze/thaw cycles were compared with previously analyzed samples. HMGB1 concentrations in simultaneously acquired arterial and venous samples were also compared. HMGB1 was assessed by standard ELISA technique, additionally we investigated the suitability of western blot in both serum and plasma samples. Results Arterial HMGB1 concentrations were consistently lower than venous concentrations in simultaneously obtained samples (arterial = 0.60 x venous; 95% CI 0.30–0.90). Concentrations in plasma and serum showed a strong linear correlation, however wide limits of agreement. Storage of blood samples at room temperature prior to centrifugation resulted in an exponential increase in plasma concentrations after ≈6 h. HMGB1 concentrations were fairly stable in centrifuged plasma samples subjected to long-term storage and freeze/thaw cycles. We were not able to detect HMGB1 in either serum or plasma from our trauma patients using western blotting. Conclusions Arterial and venous HMGB1 concentrations cannot be directly compared, and concentration values in plasma and serum must be compared with caution due to wide limits of agreement. Although HMGB1 levels in clinical samples from trauma patients are fairly stable, strict adherence to a pre-analytical protocol is advisable in order to protect sample integrity. Surprisingly, we were unable to detect HMGB1 utilizing standard western blot analysis.

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5178
Author(s):  
Qiuxia Han ◽  
Songyan Li ◽  
Bo Fu ◽  
Dongwei Liu ◽  
Maoqing Wu ◽  
...  

BackgroundThe importance of circulating antibodies as biomarkers of kidney disease has recently been recognized. However, no study has systematically described the methodology of sample preparation and storage regarding antibodies as biomarkers of kidney disease. It remains unknown whether repetitive freeze-thaw cycles, physical disturbances, storage at different temperatures or for different periods of time, or haemolytic or turbid serum samples affect antibody measurements. The aim of this study was to investigate the stabilities of antibodies associated with kidney disease in serum samples under various relevant clinical and research conditions.MethodsWe stored serum samples in the following different conditions: repetitive freeze-thaw cycles (1, 6 or 12 times), long-term storage (7 or 12 months at −80 °C), physical disturbance (1 or 8 h), and storage at 4 °C (1, 3 or 6 weeks) and room temperature (1 or 7 days). The stabilities of the anti-phospholipase A2 receptor (anti-PLA2R), anti-glomerular basement membrane, anti-myeloperoxidase and anti-proteinase 3 antibodies were evaluated with enzyme-linked immunosorbent assays (ELISA).ResultsWe found that repetitive freeze-thaw cycles did not have a significant effect on the stabilities of the abovementioned antibodies in clear serum samples. The ELISA readings of haemolytic and turbid serum samples tended to increase and decrease, respectively. Neither long-term storage at −80 °C nor physical disturbance had a significant effect on anti-PLA2R antibody stability in sealed serum samples. The concentrations of most of these antibodies increased in unsealed serum samples that were stored at 4 °C for more than 6 weeks or at room temperature for more than 7 days.DiscussionOur findings revealed that the abovementioned circulating antibodies that are used as biomarkers for kidney disease had stable physicochemical properties, structures and immunoreactivities such that they were not influenced by repetitive freeze-thaw cycles, physical disturbances or long-term storage at −80 °C. However, the ELISA readings tended to change for haemolytic, turbid and unsealed serum samples.


Author(s):  
A. Sinebryukhova ◽  
A. Shipelova ◽  
E. Darnotuk ◽  
A. Chekanov ◽  
O. Baranova ◽  
...  

The optimal conditions were selected for obtaining homogeneous nanoemulsions (NE) of lipoic acid conjugates (LA-conjugates) based on Pluronic F68 (1,8%) with a particle size not exceeding 400 nm, characterized by 97±2% encapsulation efficiency of substances in nanoparticles (NP). A heterogeneous NE (polydispersity index, PDI>0,3) with the derivative of LA and myo-inositol based on phosphatidylcholine (PC, C = 3 mg/ml) was also obtained consisting of 2 particle fractions: 20–70 nm (27%) and 122–212 nm (73%). The obtained NEs with LA-conjugates based on Pluronic F68 and PC were stable during long-term storage (more than 12 months) at room temperature. The effect of the obtained NEs of LA-conjugates on platelet aggregation (Pt) caused by arachidonic acid (AA) was determined, and a mechanism of their action was proposed.


2008 ◽  
Vol 584-586 ◽  
pp. 1039-1044
Author(s):  
Andrey Korotitskiy ◽  
K.E. Inaekyan ◽  
Vladimir Brailovski ◽  
Sergey Prokoshkin

Ti-50.26at.%Ni shape memory alloy samples were subjected to cold rolling (CR) with true strains encompassing from moderate (logarithmic strain e=0.25) to severe (e=2.1) deformation. СR with e = 0.5 and more initiated a partial austenite amorphization. The evaluation of structural changes in the material during its long-term storage was performed using Vickers microhardness (HV) technique. It was shown that during storage at room temperature up to 9 months, microhardness varied following a dome-shaped trend, thus reflecting commonly encountered interaction between two concurrent time-dependent phenomena, the first responsible for the material hardening, and the second, for the material softening. To represent such phenomena, a simple mathematical model was proposed and experimentally validated.


2005 ◽  
Vol 1 ◽  
pp. 117693510500100 ◽  
Author(s):  
Breeana L Mitchell ◽  
Yutaka Yasui ◽  
Christopher I Li ◽  
Annette L. Fitzpatrick ◽  
Paul D Lampe

Mass spectrometry approaches to biomarker discovery in human fluids have received a great deal of attention in recent years. While mass spectrometry instrumentation and analysis approaches have been widely investigated, little attention has been paid to how sample handling can impact the plasma proteome and therefore influence biomarker discovery. We have investigated the effects of two main aspects of sample handling on MALDI-TOF data: repeated freeze-thaw cycles and the effects of long-term storage of plasma at –70°C. Repeated freeze-thaw cycles resulted in a trend towards increasing changes in peak intensity, particularly after two thaws. However, a 4-year difference in long-term storage appears to have minimal effect on protein in plasma as no differences in peak number, mass distribution, or coefficient of variation were found between samples. Therefore, limiting freeze/thaw cycles seems more important to maintaining the integrity of the plasma proteome than degradation caused by long-term storage at –70°C.


Author(s):  
Margarita Ishmuratova ◽  
◽  
Damirzhan Baigarayev ◽  
Saltanat Tleukenova ◽  
Elena Gavrilkova ◽  
...  

This article presents the summarized data on cryopreservation of seeds of the medical plant Nepeta cataria. Cryopreservation is a highly promising method for saving of seed materials, allowing to organize long-term storage without viability loss. The purpose of present work is to optimize conditions of cryopreservation of seed materials of Nepeta cataria. Assessment of seed survival rate in the storage showed a linear decrease in seed viability and energy of germination. After 30 months of storage at the low positive temperature (+5 ºC) in paper pack seed rate decreased to 12.0 % and energy of germination to 11.2 %; after 4 years of storage seeds lost viability. During conduction of research the type of container, condition of thawing, optimal moisture of seeds and cryoprotectants are optimized. The optimal container for cryopreservation in liquid nitrogen was plastic cryo tubes; defrosting at room temperature. The best seed rate is found at moisture 3 %; the best cryoprotectant was glucose, the optimal concentration was 15 %. The result of the research is used for creation of the long-term storage medicinal cultures’ seed bank in the liquid nitrogen.


2018 ◽  
Vol 29 (1) ◽  
pp. 94-111 ◽  
Author(s):  
Tomás Barranco ◽  
Asta Tvarijonaviciute ◽  
Damián Escribano ◽  
Fernando Tecles ◽  
José J Cerón ◽  
...  

Introduction: In this report, we aimed to examine the stability of various analytes in saliva under different storage conditions. Materials and methods: Alpha-amylase (AMY), cholinesterase (CHE), lipase (Lip), total esterase (TEA), creatine kinase (CK), aspartate aminotransferase (AST), lactate dehydrogenase (LD), lactate (Lact), adenosine deaminase (ADA), Trolox equivalent antioxidant capacity (TEAC), ferric reducing ability (FRAS), cupric reducing antioxidant capacity (CUPRAC), uric acid (UA), catalase (CAT), advanced oxidation protein products (AOPP) and hydrogen peroxide (H2O2) were colorimetrically measured in saliva obtained by passive drool from 12 healthy voluntary donors at baseline and after 3, 6, 24, 72 hours, 7 and 14 days at room temperature (RT) and 4 ºC, and after 14 days, 1, 3 and 6 months at – 20 ºC and – 80 ºC. Results: At RT, changes appeared at 6 hours for TEA and H2O2; 24 hours for Lip, CK, ADA and CUPRAC; and 72 hours for LD, Lact, FRAS, UA and AOPP. At 4 ºC changes were observed after 6 hours for TEA and H2O2; 24 hours for Lip and CUPRAC; 72 hours for CK; and 7 days for LD, FRAS and UA. At – 20 ºC changes appeared after 14 days for AST, Lip, CK and LD; and 3 months for TEA and H2O2. At – 80 ºC observed changes were after 3 months for TEA and H2O2. Conclusions: In short-term storage, the analytes were more stable at 4 ºC than at room temperature, whereas in long-term storage they were more stable at - 80 ºC than at – 20 ºC.


1992 ◽  
Vol 38 (2) ◽  
pp. 304-304 ◽  
Author(s):  
Yu-Ming Chen ◽  
Nitza M Cintrón ◽  
Peggy A Whitson

Biomics ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 552-563
Author(s):  
R.R. Garafutdinov ◽  
A.R. Sakhabutdinova ◽  
A.V. Chemeris

The simplest and most common method of long-term storage of DNA samples at present is the storage of their frozen solutions, which, however, has a number of disadvantages, including the destruction of DNA molecules during freezing and thawing, as well as energy consumption and the likelihood of losing valuable samples in the event of possible accidents. In this regard, long-term storage of DNA samples at room temperature in a dried state is preferable, especially since an even greater increase in the number of stored DNA samples is planned due to the planned preservation of non-biological data in this molecule, which is recognized at the International Economic Forum 2019 among the 10 most important innovative technologies as “DNA Data Storage” of the near future of mankind. Such storage requires the exclusion of hydrolysis and oxidation of DNA molecules under the action of water and reactive oxygen species, which can be achieved by placing DNA in an inert anhydrous atmosphere, including in the presence of additional ingredients in the form of, for example, trehalose, imitating wildlife, since it is known that this simple disaccharide, capable of vitrification, protects a wide range of anhydrobiont organisms from adverse environmental conditions. Currently, there are a number of technologies that provide long-term storage of DNA at room temperature, including those available from commercial sources, but not all problems have yet been solved, which is reflected in this review article.


Sign in / Sign up

Export Citation Format

Share Document