Search

We developed a model of blood hyperviscosity avoiding extreme impact on the blood. The model shows reproducibility in rat blood under common storage conditions (4±1°C; stabilization with citrate-phosphate-glucose additive solution). Storage of rat blood under these condition leads to impairment of its rheological properties, which manifested in an increase in blood viscosity in a wide range of shear rates (3-300 sec—1). An increase in blood viscosity appeared the first day of storage and reached a maximum on the third day. During further 11-day storage, the blood viscosity did not change significantly. A hybrid macromolecular compound O-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoyl)-(1→6)-α-D-glucan improved the hemorheological properties during storage. The most pronounced effect was observed on the third day of storage and manifested in a decrease in blood viscosity in the range of shear rates of 50-300 sec—1. Thus, storage of rat blood with citrate-phosphate-glucose additive solution for 3 days at 4±1°C reproduces the phenomenon of blood hyperviscosity; this model can be used to screen agents with hemorheological activity. [ABSTRACT FROM AUTHOR]

Coagulation and optical (based on chromogenic substrate) methods were employed to examine antithrombin activity of erythrocytes and erythrocyte-derived microvesicles isolated days 7, 14, 21, and 28 on erythrocyte storage. The erythrocyte-derived microvesicles decelerated fibrin clot formation from fibrinogen in the presence of exogenous thrombin both with and without heparin. Microvesicles reduced optical density of chromogenic substrate. These data suggest that erythrocyte-derived microvesicles display a prominent antithrombin activity, which significantly increases during erythrocyte storage. [ABSTRACT FROM AUTHOR]

Purpose: There is substantial conjecture regarding the clinical significance of packed red blood cell (PRBC) changes that occur during in vitro storage. Here, we present a meta- and systematic analysis of adult studies published between 1994 and 2015 with the aim of updating existing quantitative reviews and providing a comprehensive cover of the six most commonly studied outcomes-mortality, infection, renal dysfunction, multiple organ dysfunction syndrome (MODS), thrombotic complications and prolonged hospital length of stay.Methods: Computerised searches of Pubmed and EMBASE identified publications that reported target outcomes and PRBC storage duration prior to transfusion. Bibliographies of relevant literature were manually searched to incorporate missed studies. Randomised controlled trial (RCT) data was meta-analysed using a random effects model with Cochrane Collaboration Review Manager (RevMan) version 5.1 software. Observational investigations were systematically reviewed.Results: Sixty-four papers were selected covering 462,581 patients with the majority of studies being observational in nature. Meta-analysis of eight RCTs demonstrated a trend towards decreased mortality with stored PRBC transfusion; albeit this effect was not statistically significant (OR 0.91, 95 % CI 0.78-1.05, p = 0.20). In a small subset of intensive care unit (ICU), cardiac surgery and trauma patients; observational studies suggested that prolonged storage may be correlated with increased mortality. Trauma and cardiac surgery patients appeared to be most susceptible to the potential infectious complications of stored PRBCs. Stored PRBCs were unlikely to affect thrombotic complications or hospital length of stay. There were inadequate data to determine whether stored PRBCs had clinically relevant effects on renal dysfunction and MODS.Conclusion: Although literature presents a concerning picture of potential storage complications, current findings are too inconsistent to drive changes in clinical practice. Results from current RCTs will likely play a role in PRBC age guidelines for cardiac surgery and ICU patients. However, these studies may be less efficacious at detecting small effects that are limited to specific subpopulations. [ABSTRACT FROM AUTHOR]

Lysostaphin, a staphylococcus-derived staphylocidal substance, has widely been used in assays of granulocyte phagocytic and bactericidal capability. It rapidly kills extracellular bacteria. Thus, a separate determination of intracellular surviving bacteria can be performed. One prerequisite for this approach is the safe inactivation of lysostaphin (usually brought about by trypsin) before the intracellular bacteria are externalized for plating. This inactivation has been found by others to be incomplete. Data are presented demonstrating a safe inactivation of lysostaphin by trypsin, if the pH value is maintained within the alkaline range. A low variation of results is obtained by plotting the total number of bacteria killed per incubate vs the logarithm of initial bacterial inoculum or of the intracellular surviving bacteria, leading to linear regression lines. The variation of the results increases greatly for initial bacteria/granulocyte proportions of > 5/1. The results obtained for two different St. aureus strains are significantly different. Dexamethasone pretreatment (12 mg p.o. within 8 h) had no detectable influence, when fresh blood was assayed, while blood storage at room temperature for 12 h (without dexamethasone pretreatment) led to a significant functional impairment, mainly of bactericidal capability when analyzed in a pairwise fashion. A major limitation of this kind of assays is that killed bacteria cannot be determined directly. [ABSTRACT FROM AUTHOR]

Copyright of Blut: Zeitschrift für die Gesamte Blutforschung is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Blut: Zeitschrift für die Gesamte Blutforschung is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We evaluated structural damage to DNA (%TDNA) in blood leukocytes from healthy donors of different age at different periods (0-6 days) of blood storage at 4-8°C. It was found that the basal level of DNA damage increased and intracellular antioxidant level decreased during storage. Mean %TDNA was 6.8±3.3% in the fresh blood and 19.2±8.1% after 5-day storage. The experiments with exposure to reactive oxygen species induced by irradiation suggest that depletion of low-molecular-weight endogenous antioxidants occurs as soon as after 5-h storage. Our results suggest that storage time should be taken into account when assessing the basal and induced levels of leukocyte DNA damage by the comet assay. [ABSTRACT FROM AUTHOR]

Long-term monitoring of blood glucose in diabetic patients is a powerful tool in the clinical practice, and HbA assay is probably suitable for this purpose. The importance of this parameter requires a high degree of affidability together with routine feasibility. In this work we showed that a number of factors can interfere with the precision and accuracy of glycosylated hemoglobin detection by the presently investigated method. However, care in the storage of samples and in the control of the operating temperature may be easily obtained and lead to satisfactory results. [ABSTRACT FROM AUTHOR]

Human whole blood was irradiated with 2.5 Gy of 220 kVp X-rays and stored before culture with 9.7 μM BrdU and 19.4 or 38.7 μM BrdU for 0, 24, 48 and 72 h. The frequency of dicentrics and ring chromosomes was determined in cells staining as first division (M1) metaphases with the fluorescence plus Giemsa technique. Storage had no influence on the observed aberration yields in 44 h cultures containing 9.7 μM BrdU. In 66 h cultures at 19.4 μM BrdU the observed yields after 2 and 3 days' storage were significantly lower as compared to cultures from fresh blood. No storage effect was revealed in 66 h cultures containing 38.7 μM BrdU. In cases where cytogenetic radiation dosimetry has to be carried out using blood samples which have been in transit for 2-3 days, the findings are of relevance for a correct determination of the chromosome damage in M1 cells. [ABSTRACT FROM AUTHOR]