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Red blood cell enzyme tests
Various metabolic processes occur in red blood cells: glycolysis, the pentose phosphate pathway for the oxidation of glucose, the reduction of glutathione, the destruction of hydrogen peroxide and other metabolic reactions. Violations of these processes can be associated with hereditary defects in the synthesis of enzymes (enzymopathy). The most common red blood cell enzyme pathology is a violation of the synthesis of glucose-6-phosphate dehydrogenase (G-6-FDH), a key enzyme of the pentose phosphate pathway for glucose oxidation. There is an inverse relationship between the activity of G-6-FDG and erythrocyte resistance, so a deficiency of G-6-FDH in the cell can lead to hemolysis of red blood cells (hemolytic crisis) when patients take a number of drugs that act as oxidants - antimalarials (primaquine), acetylsalicylic acids, sulfanilamides, nitrofurans, 5-NOC, PASK, phenacitin, etc. To diagnose G-6-FDH deficiency, both qualitative methods and quantitative determination of its activity in red blood cells are used.
Heinz Taurus Education Test - Erlich
In healthy people, the formation of single red bodies is observed in red blood cells. A small number of Heinz bodies are found in the cells of newborns or patients after splenectomy.
In red blood cells with a deficiency of G-6-FDG, 4-6 bodies are found. The sample is nonspecific because Heinz bodies appear in red blood cells with an overdose of sulfa drugs, poisoning with aniline dyes, deficiency of other enzymes (glutathione reductase, 6-phosphogluconate dehydrogenase), and carriers of unstable hemoglobins.
Qualitative Motulsky-Campbell technique
In healthy people, the mixture discolors after 40-55 minutes.
Slowing down the bleaching time of the mixture for more than 90 min indicates a deficiency in red blood cells G-6-FDG
With hemolytic enzyme deficiency anemia, bleaching occurs after 3-24 hours.
Qualitative Bernstein technique
In healthy people, discoloration of the mixture occurs after 15-20 minutes.
Elongation of bleaching time indicates a deficiency in red blood cells G-6-FDG. Incomplete discoloration in 30 minutes corresponds to a slight decrease in enzyme activity, and the absence of discoloration by this time corresponds to a sharp decrease.
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Red blood cell enzyme tests
- OTHER FUNCTIONAL TESTS
Eye-cardiac reflex (Danyini-Ashner test) Used to assess the reactivity of the parasympathetic division of the ANS. Test procedure: After a 15-minute rest, an ECG is recorded for 1 minute with the determination of the average heart rate (heart rate). Without stopping the registration of the ECG, the fingertips press for both eyeballs for 15-25 seconds until a slight pain
- Red blood cell count
The calculation of the number of red blood cells in 1 μl of blood is based on blood dilution (200), the number of squares counted (80) and the volume of 1 small square (1/4000 μl) according to the following formula: X = (ax 4000x200) / 200, where X is the number red blood cells in 1 μl of blood; and - the number of counted red blood cells. As a result of the reduction X = a x 10,000. The causes of errors in the calculation of red blood cells: 1) inaccuracy in taking blood
- Stress test
To identify ischemia in most patients with suspected stable angina, ECG recording during exercise tests is a more sensitive and specific method than at rest. Stress and pharmacological tests provoke myocardial ischemia by increasing myocardial oxygen demand (treadmill test, VEM, dobutamine test) or reducing oxygen delivery to the myocardium
- Hereditary hemolytic anemia due to impaired activity of red blood cell enzymes
Enzymatopathies or non-spherocytic hemolytic anemias are characterized by a hereditary decrease in the activity or instability of red blood cell enzymes. Inherited autosomal recessive or X-linked recessive type. The most severe hemolytic manifestations are observed, as a rule, in homozygous carriers with an almost complete absence of enzyme activity in
- Erythrocyte resistance
To assess the physicochemical properties of red blood cells, their resistance to various influences is examined. Most often, the osmotic resistance of red blood cells is determined in the clinic. Distinguish between minimum and maximum resistance. The minimum resistance of red blood cells is determined by the maximum concentration of a hypotonic (less than 0.85%) sodium chloride solution (gradually
- Colloidal sedimentation tests
To study protein metabolism in CDL colloidal sediment samples are widely used. The main reactions of this type are thymol and sublimate tests. The thymol test is based on the turbidity of the mixture: when the serum interacts with a saturated solution of thymol in veronalon buffer. The determination of the degree of turbidity is carried out photometrically at a wavelength of 630-690 nm against a working reagent
- Conclusion according to the results of a stress test
In conclusion, according to the results of a stress test, indicate: 1. Demographic data: surname and name of the patient, age or date of birth, gender, body weight, height, date of the study, 2. The purpose of the stress test. 3. Clinical features of the patient: risk factors for coronary heart disease, the use of drugs, ECG changes at rest. 4. Research results: • used
- Red blood cells
Red blood cells are the largest cell population. In the bloodstream under normal physiological conditions, the red blood cell has the shape of a biconcave disc. The dry substance of an erythrocyte contains about 95% of hemoglobin, the remaining 5% are other proteins, lipids, enzymes. The main function of red blood cells is to supply tissues with oxygen and transport carbon dioxide. They are involved in
- PHARMACOLOGICAL SAMPLES
Sample with adrenaline or insulin Used to assess the reactivity of both departments of the ANS. Sample methodology: In the morning, not earlier than 1.5 hours after eating after a 15-minute rest, an ECG is recorded for 1 minute with the average heart rate determined (heart rate). Then, 0.3 ml of a 0.1% solution of adrenaline or insulin is administered under the skin of the shoulder at a dose of 0.15 U / kg. Register
- Exercise Dosed Samples
An ECG recorded at rest, outside a pain attack, in a patient without a history of MI, may be normal. During the test with dosed physical activity, the patient performs an increasing load on the treadmill or VEM, while heart rate and ECG are constantly recorded, blood pressure is monitored at regular intervals (1-3 minutes). Treadmill test in comparison with VEM has both advantages and
- Vagus tests.
Against the background of stable hemodynamics and clear patient consciousness, the relief of paroxysm of supraventricular tachycardia with a narrow QRS complex begins with techniques aimed at irritating the vagus nerve and slowing the passage through the atrioventricular node. Conducting vagal tests is contraindicated in the presence of acute coronary syndrome, suspected pulmonary embolism, in pregnant women. The following tricks may
- PHYSICAL LOAD SAMPLES
Stress tests are a common as well as affordable method for diagnosing and examining patients with cardiovascular diseases. Back in 1929, Master and Oppenheimer developed a standardized load protocol to assess the functional status of patients with coronary artery disease. Over the next 30 years, the mechanisms of ST segment displacement, the influence of the position of the electrodes on ECG changes were studied,
- Red blood cell sedimentation rate
Red blood cell sedimentation - the property of fresh blood cells to freely settle on the bottom of the vessel while stabilizing it in a non-coagulating state with an anticoagulant. The spontaneous (not to be confused with hematocrit!) Erythrocyte sedimentation occurs due to their higher relative density compared to that in plasma. Red blood cells, moving down, displace the plasma up. Normal upward and downward impact