Hemolysis tests

Kadoma, Y.. Nakabayashi, N., Masuhara, E. and Yamauchi, J. (1978) Synthesis and hemolysis test of the polymer containing phosphorylcholine groups. Kobunshi Ronbunshu, 35, 423-427. 

Deficiency of vitamin E is characterized by low serum tocopherol levels and a positive hydrogen peroxide hemolysis test. This deficiency is believed to occur in patients with biliary, pancreatic, or intestinal disease that is characterized by excessive steatorrhea. Premature infants with a high intake of fatty acids exhibit a deficiency syndrome characterized by edema, anemia, and low tocopherol levels. This condition is reversed by giving vitamin E. 

Experiment. Prepare hemolyzed plasma or serum by spiking hemolyzed whole blood into nonhemolyzed plasma at low QC level. Hemolyzed blood for these experiments can be prepared by freezing, thawing and centrifuging whole blood. Three levels of hemolysis are used 0 % (100 % normal plasma/serum), 0.5 % of above (99.5 % normal plasma/serum), and 2 % of above (98 % normal plasma/ serum). Analyze six (6) replicates for each group. Compare the mean instrument response of the 0.5 % or 2 % hemolysis test samples to that of the 0.0 % control group. 

These in vitro cytotoxicity studies are not indicative of in vivo toxicity but rather provide a method to classify the CDs for their potential to destabilize or disrupt cellular membranes. In fact, when whole blood is used instead of erythrocytes for the hemolysis tests, the cytotoxicity of the CDs is diminished 10-fold by the presence of hydrophobic serum components. Thus, the membrane damaging effects of the CDs are observed in vivo only under situations of high concentrations. 

Note The international unit of vitamin E is equal to one mg of standard eff-o-tocopheryl acetate. The d-form is more active 1 mg = 1.36 I, U. J- -Tocopheryl acetate has 42% of rhe activity of d-o- -rocopheryl acetate in the rat hemolysis test. Based on this activity a potency ratio of 1.4 1.0 for d-a-tocophery] acerate compared to dl-a-tocopheryl acetate has been established. 

In this work, porous AI2O3 ceramics were fabricated by freeze casting from AI2O3 aqueous ceramic slurries, and its biological properties, such as, in vitro cytotoxicity, acute hemolysis tests, and skin sensitization reactions were also investigated. 

The disinfected ceramics were immersed in culture solution DMEM (Dulbecoo s Modified Eagle s Medium) for cytotoxicity test and physiological saline was also used to get the extract for hemolysis test. The extract experiment was conducted under 37°C for 24 h and 10 ml physiological saline for each 0.2 g porous AI2O3 was used. 

As to the biomaterial for human tissue replacement, it is necessary to demonstrate if the material has any effect on the biological properties of the tissue. Bioceramics exhibit some possible toxic reactions due to metal ions leaching from the ceramics, resulting in the tissue dying or heavy reactions. In this experiment, cytotoxicity test, hemolysis test as well as skin irritation were conducted to value the biocompatibility of the porous AI2O3 ceramics. 

The acute hemolysis test The results of the hemolysis test are presented in table 4. The absorbance is based on the hemoglobin solubility from the erythrocytes. Thus, the absorbance corresponds to the number of hemolyzed erythrocytes. The data directly reflected if newly prepared porous AI2O3... 

According to the results of cytotoxicity test, acute hemolysis test, skin irritation test, the in vitro biological reactions of the porous AI2O3 ceramics prepared via freeze casting is biosafe and can be further used in implant experiments. 

The. animal work will be described only sufficiently to allow the reader to appreciate lietter the discussion of the human studies. When it became apparent in 19.55 that the peroxide hemolysis test was dependent not only on the tocopherol level of the blood but also upon the level of linoleic acid (and other autoxidizable components) in the stroma of the erythrocyte, animal experiments were designed to obtain more exact correlations between tocopherol needs and linoleic acid intake. This relationship between linoleic acid content of the diet and the incidence of chick encephalomalacia (Century and Horwitt, 19.58) was not recorded until later (Century et al., 19.59 Century and Horwitt, 19.59) when observation of cerebellar encephalomalacia in an infant that had been fed a commercial cottonseed oil preparation intravenously came to our attention (Horwitt and Bailey, 1959). In the meantime, there had been a number of reports to certify the relationship between linoleic acid consumption and chick encephalomalacia (Dam et al, 19.58 Machlin and Gordon, 1960). With the advent of better gas chromatographic techniques, it was soon possible to show that the linoleic acid content of the cerebellum was diet dependent (Horwitt et al., 1959 Witting et al., 1961). The marked effects of diet on the fatty acids of the mitochondria of chick brains has also been reported (Horwitt, 1981a). The levels of linoleic acid are much lower in brain tissues than in any tissue analyzed to date and this relatively low linoleic acid level may be considered a characteristic of brain tissue. The significance of this difference is not known. It is of interest to note that the current interpretations of the effect of more unsaturated fats on the production of chick encephalomalacia were anticipated by Dam in 1944. 

The plasma tocopherol technique used was essentially simihir to that described by Quaife and Biehler (1945) and the peroxide hemolysis method used was a modification of that reported by Rose and GySrgy (1952). The most important artifact in the peroxide hemolysis test is the varying rate at which different batches of peroxide are decomposed. This artifact does not change the rank order of the results on a given day but precautions must be taken to standardize the peroxide if results obtained at different times are to be compared. In recent years, the 2.5% peroxide solution used in the test has been aged in Pyrex glass bottles for several days before use, and this procedure has made the results more uniform from day to day. 

In order to estimate whether there is any possible relationship of the in vitro peroxide hemolysis test with the survival rate of the erythrocytes... 

In sophisticated areas, milled wheat flour is artificially aged and bleached, and chlorine dioxide is now preferred as the bleaching agent. Using the paper chromatography method, Moore et al. (1957) observed that 80% of the tocopherols in flour were destroyed when 30 parts per million (ppm) of chlorine dioxide were used to bleach. Later, they confirmed this result by hemolysis tests and rat assays (Moore et al., 1958). 

No. 276 Disposable blood oxygenator set 1. Extractive substances i. Transparency and appearance ii> Foam teat ill. pH (The difference to the blank solution) iv. Potassium permanganate-reducing substances V. Residue on evaporation Vi. Zink vii. Lead 2. Hemolysis test 3. Pyrogen test... 

No. 273 and No. 301 are the specification for plastics used in medical practice, in Japan. These testing items consist of extraction test, heavy metal analysis, acute toxicity test, hemolysis test and pyrogen test. All the results of the examination passed the regulations and indicate that the 1, 2-PBD is safe enough to be used as a plastic packaging for foods. In the case of acute toxicity, the number of deaths of the mice was zero. Further, it is assumed that the 1, 2-PBD has the possibi-bility to be applied to the medical plastics field. 

An unoommon sign, which cannot be detected from the smear, but can be elicited by a sucrose water test" of peripheral blood, is transient paroxysmal nocturnal hemoglobinuria (PNH), which may first occur insidiously during a period of established aplastic anemia, and may be followed within one to a few years by the appearanoe of rapidly fatal aoute myelogenous leukemia. Clinioal detection of PNH, whioh ooours in only one or two peroent of those destined to have aoute myelogenous leukemia, may be difficult if the sucrose water test is positive, the somewhat more definitive Ham test, also known as the acid-serum hemolysis test, may provide confirmation. 

New compounds were pushed along a pass/fail multistep testing protocol that followed the order water solubility stability in water, plasma, and whole blood and hemolysis. Each failure resulted in the compound being discarded. Those passing the hemolysis test entered cytotoxicity tests in several cell lines, and, when positively cleared, entered the in vivo animal model test. The best readouts of acute Uver failure rescue were obtained for the family of isocyanide derivatives Mo(CO)3 (CNCRi r2COOH)3. ... 

The cytotoxicity of star-shaped FOL-PEG-PCL micelle to MCE-7 cell was evaluated using MTT assay method. Fig. 3 demonstrates the cell viability after 24 hours incubation with polymeric micelle at various concentrations (0.001, 0.01, 0.1, 0.5 and 1.0 mg/irL). The results showed that cell viability of MCF-7 cell decreased as the concentration of micelle increased. However, the lowest cell viability approximately 92% was observed at a concentration of 1.0 mg/irL. The cells viability assay indicates that the star-shaped FOL-PEG-PCL micelle has generally low cytotoxicity to the MCF-7 cells with concentration up to 1.0 mg/irL. The data of macrophage response and hemolysis test suggest that the star-shaped FOL-PEG-PCL micelle prepared in this study had a moderate to low in vitro toxicity and could be safe for intravenous injection. 

Hemocompatibility (IS 10993-4) Evaluates the effects on blood and blood components by blood-contacting materials/devices. Example, static hemolysis test RRBC. 

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