Hemolysis phenomenon

The answers are 484-k 485-j. (tlardman, pp 1061-1062, 1682-1685.) Sulfonamides can cause acute hemolytic anemia. In some patients it mayr be related to a sensitization phenomenon, and in other patients the hemolysis is due to a glucose-6-phosphate dehydrogenase deficiency Sulfamethoxazole alone or in combination with trimethoprim is used to treat UTls. The sulfonamide sulfasalazine is employed in the treatment of ulcerative colitis. Daps one, a drug that is used in the treatment of leprosy, and primaquine, an anti mala rial agent, can produce hemolysis, particularly in patients with a glucose-6-phosphate dehydrogenase deficiency. 

One such distribution phenomenon can occur as a result of hemolysis of the sample. Preparation of the TDM sample involves centrifugation to separate the cells and platelets from the plasma. If the sample is hemolyzed, then the centrifugation may not adequately separate cell fragments from the plasma. That can result in an increase in the apparent concentration of drug in plasma. 

Saponins consist of a terpenoid core (the aglycone), having oxygenated positions bound to sugar moieties (up to ten monosaccharidic units). In water they form colloidal solutions which foam on shaking and precipitate cholesterol. When saponins are near cell membranes, their interaction with cholesterol may create pore-like structures that eventually cause the membrane to burst. Hemolysis is an example of this phenomenon (i.e. the distraction of erythocyte membranes, but not hemoglobin). Occasionally, they cause hypersecretion, which could explain their expectorant activities and also their toxicity to fish. 

In similar experiments using red blood cells it has also been demonstrated that when cells were frozen at approximately 50,000°C/min by spray-freezing and then thawed very rapidly (7000°C/min), the hemolysis ratio was lower than that obtained from rapid freezing. The ice crystal diameter in these experiments was less than 500 nm. A similar phenomenon might be expected to occur in microorganisms. 

Mammalian red blood cells have a biconcave (doughnut-like) shape. If red blood cells are placed in a 0.3 M NaCl solution, there is little net osmotic movement of water, the size and shape of the cells stay the same the NaCl solution is isotonic to the cell. If red blood cells are placed in a solution with a lower solute concentration than is found in the cells, water moves into the cells by osmosis, causing the cells to swell such a solution is hypotonic to the cells. When red blood cells are placed in pure water, water rapidly enters the cells by osmosis and causes the cells to burst, a phenomenon known as hemolysis. If the red blood cells are placed in a solution with a higher solute concentration, water moves out of the cell by osmosis, the cell becomes smaller and crenated in shape such a solution is hypertonic to the cells. 

Two studies have provided insights into the incidence and risk factors of the immune-mediated comphcations of interferon alfa in patients with chronic myeloid leukemia. In the first study, 13 of 46 patients had autoimmune manifestations consisting of a combination of autoimmune thyroiditis in four, a direct antiglobulin test without hemolysis in eight, cryoagglutinins in one, Raynaud s phenomenon in two, and chronic autoimmune hepatitis in one (343). Overall, six patients had chnically symptomatic manifestations after a median of 15 months of treatment. In the second study, there were autoimmune diseases in seven of 76 patients after a median of 19 months of treatment, including hypothyroidism in one, immune-mediated hemolysis in two, systemic lupus erythematosus in two, Raynaud s phenomenon in one, and mixed connective tissue disease in one (344). In... 

Renal damage ototoxicity bone marrow depression hemolysis hypomagnesemia peripheral neuropathy hypocalcemia hypokalemia Raynaud s phenomenon sterility hypophosphatemia hyperuricemia anorexia... 

The severity of drug-induced immune hemolytic anemia is usually a function of the rate of hemolysis. Hemolytic anemia caused by drugs via the hapten/adsorption and autoimmune mechanisms tend to be slower in onset and mild to moderate in severity. Conversely, hemolysis prompted via the neoantigen mechanism (innocent bystander) phenomenon may have a sudden onset, lead to severe hemolysis, and result in renal failure. The treatment of drug-induced immune hemolytic anemia includes the removal of the offending agent and supportive care. Glucocorticoids are usually unnecessary, and practitioners have questioned their efficacy. ... 

The osmotic pressure phenomenon manifests itself in many interesting applications. To study the contents of red blood cells, which are protected from the external environment by a semipermeable membrane, biochemists use a technique called hemolysis. The red blood cells are placed in a hypotonic solution. Because the hypotonic solution is less concentrated than the interior of the cell, water moves into the cells, as shown in Figure 12.14(b). The cells swell and eventually burst, releasing hemoglobin and other molecules. 

Flavonoids can interact with 02 in two different ways they can combine chemically with 02 or they can transfer the excitation energy of 02 to the flavonoid molecule, which then enters an excited state. The latter phenomenon is called quenching [35]. Flavonoids have been reported to quench singlet oxygen [17, 135-137], but only Toumaire et al. tried to establish a structure-activity relationship [17]. Sorata et al. studied the suppression of photosensitized hemolysis of human erythrocytes by the flavonols quercetin and rutin [135]. At lower concentrations, the effect of quercetin was more important than that of rutin [135]. According to Takahama et al., quercetin suppressed >02-dependent photobleaching of... 

Soiutions that have identical osmotic pressures are said to be isotonic solutions. Fluids administered intravenously must be isotonic with body fluids. For example, if red blood cells are bathed in a hypertonic solution, which is a solution having an osmotic pressure higher than that of the cell fluids, the cells will shrivel because of a net transfer of water out of the cells. This phenomenon is called crenation. The opposite phenomenon, called hemolysis, occurs when cells are bathed in a hypotonic solution, a solution with an osmotic pressure lower than that of the cell fluids. In this case, the cells rupture because of the flow of water into the cells. 

One of the most striking phenomenon discovered in the case of Q-P(TDAE)n was the effect of Ae order of addition of the charged species present in resuspended RBC on agglutination and hemolysis. Some of the studied polycations behaved similarly whereas others did not show any sensitivity. Hemolysis of desialylated RBC suspended in albumin was not significantly affected by the order of addition, thus showing that the sialic acids did play a significant complexing role, as borne out by the fixation of the fluorescence labeled Q-P(TDAE)n polycationic molecules at the cell surface. 

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