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Biomedical subjects

L N Tarasova

Publications and source records attributed to L N Tarasova.

At least 19 recordsLinked to original sources
PubMed2004

[Obtaining active extracts for use in production of soluble thromboplastin].

Methods of obtaining (from cadaveric human brain) the highly-active extracts to be used later as raw-materials for thromboplastin manufacturing, which is applied to determine the prothrombin (thromboplastin) time of human plasma or blood, are described in the paper. The study resulted in defining the optimal requirements to choosing the raw-materials, storing regime, centrifuging and extraction. The thus elaborated technology of soluble thromboplastin manufacturing ensures the production of a reagent with a high sensitivity to a changing level of factors VII and X and to a reducing activity of the prothrombin complex, which is achieved through the impact of indirect anticoagulants.

Brain Chemistry↗
PubMed2002

[Effect of activators for activated partial thromboplastin time test on its results in the tube and automated test versions].

Effects of activators used in combination with partial thromboplastin (PT), manufactured by the Kirov Institute of Hematology and Blood Transfusion, on the results of the activated partial thromboplastin time (APTT) test and its sensitivity to heparin were studied. Kaolin manufactured in Russia and by Aldrich firm and silica from Sigma were used. The method was reproduced in tubes and on Organon Teknika photooptic coagulometers: semiautomatic Coag-A-Mate XM and automated Coag-A-Mate RA-4. The concentration and optical density of the activator affected the results of APTT test, which prompts the use of kits calibrated for the PT/activator combination but not separate reagents. Combination of PT manufactured by the Kirov Institute and suspension of Russian kaolin ensured high sensitivity of the method to heparin content in the plasma and good reproducibility of the method both in tubes and on Organon Teknika coagulometers: coefficient of variation of APTT in all variants of the tube test were no higher than 10% and in the automated variant 2.6-6.2%.

Autoanalysis↗
PubMed2000

[The quality indices of the Quick method using thromboplastin reagents performed manually and instrumentally].

The reproduction and results of Quick's method with tissue thromboplastin (Kirov Institute of Hematology and Blood Transfusion--KIHBT) and Excel and Excel S simplastins (Organon Teknika, Netherlands) in the tube and automated versions were compared. Semiautomated coagulometer COAG-A-MATE XM and automated COAG-A-MATE RA-4 of the same firm were used. Three Verifi plasmas (Organon Teknika) with different activities of factors II, VII, IX, and X were used. Tests with thromboplastin manufactured by KIHBT were well reproduced both in the tube and automated modifications (CV < 10%). This thromboplastin can be used for monitoring the efficiency of therapy by indirect anticoagulants. For evaluating the correlation between results, plasma samples from 21 donors and 12 patients treated by indirect anticoagulants with the prothrombin index (PI) lower than 75% were analyzed. The PI of the tube and automated modifications were in good correlation. Tests with the Russian thromboplastin showed high coefficients of correlation between the two modifications of Quick's test, which recommends the use of these device-reagent combinations for evaluation of PI.

Blood Coagulation Tests↗
PubMed2000

[Hemostatic changes during the treatment of acute promyelocytic leukemia with all-transretinoic acid].

AIM: To study hemostasis in ATRA treatment of acute promyelocytic leukemia (APL). MATERIAL AND METHODS: Hemostasis was studied in 8 newly admitted APL patients treated with ATRA. All of them had hemorrhages, thrombocytopenia 5-15 x 10(9)/l at diagnosis, laboratory signs of the DIC syndrome at induction therapy. RESULTS: Hemorrhage arresting was seen on the ATRA therapy day 14 to 30. Duration of thrombocytopenia under 20 x 10(9)/l was 5.8 +/- 1.8 days. After 7 days of ATRA therapy coagulation tests improved with some hypercoagulation tendency. Subsequent condition of hemostasis was considered as normo/hypercoagulation accompanied by constant thrombin persistence (in the presence of FDP) and depression of hageman-dependent fibrinolysis even in remission. A case of ileofemoral thrombosis followed by fatal thromboembolism of the pulmonary artery is reported. CONCLUSION: It is suggested to use heparin, especially low molecular weight heparin when there are signs of hypercoagulation in APL patients.

Adolescent↗
PubMed1997

[Immunological aspects of tuberculosis uveitis pathogenesis].

Based on clinical and immunological examinations of 251 patients with tuberculous uveitis (TU), 3 types of its course (productive, exudative, and mixed) were identified. The immunopathologic pattern of each type was found to be different: the productive type was characterized by delayed hypersensitivity, the exudative one had immediate hypersensitivity, and the mixed one had both. The immunogenetic markers of mixed TU were defined. These included HLA antigens, such as A2, B7, B21, and B27.

Adolescent↗
PubMed1995

[Pathomorphosis of tuberculous uveitis and keratitis].

Pathomorphosis of tuberculous uveitis and keratitis was investigated as regards present-day clinical presentation and literature data on prebacterial period. There was chronic productive inflammation, exudative inflammation and mixed tuberculous infection. Pathomorphosis was evident from a sharp diminution of uveitis and keratitis incidence and severity at young age, in more apparent exudative response, polymorphism of clinical symptoms and more frequent recurrences.

Adult↗
PubMed1991

[The use of lyophilized plasma as a reference sample for determining factor VIII].

The activity of lyophilized Soviet reference plasma Factor VIII was measured by a single-stage Papayan and Khrolova's method. This factor is referent in respect of the prothrombin complex factors, stored for 18-43.5 months. Factor VIII activity was found to be within 55-135 percent. Differences in the values of antihemophilic globulin activities obtained in parallel studies in different days may be explained by the fact that the native control was not standard. The results are promising as regards the possibility of using lyophilized donor reference plasma as a reference reagent for estimation of Factor VIII activity.

Blood Preservation↗
PubMed1991

[The evaluation of lyophilized plasma as a reference standard for the prothrombin complex].

Analysis of a number of parameters of a lyophilized donor plasma reference sample to be used for the assessment of the prothrombin complex factors has shown the stability of this sample over the course of 14 months (a follow-up period). The sample may be used as a reference one in estimation of plasma prothrombin complex factor activities, and of PPSB activity. The reference sample activity should be estimated from the fresh donor plasma native pool, whose procoagulant activity is conventionally estimated as 100% or 1 U/ml. Use of a lyophilized reference sample helps obtain objective results compatible within this country, particularly so if all biologic reagents included in the test systems are standardized.

Blood Coagulation Factors↗
PubMed1990

[A lyophilized reagent for standardization of the activated partial thromboplastin time].

Native partial thromboplastin, prepared from cadaver brain thromboplastin (a reagent), is a cephalin analog used to detect disorders in the first phase of coagulation. It was lyophilized with the aim of its stabilization, potential commercial manufacture, and introduction into practical clinical laboratories. Native emulsion was distributed into 0.2 ml penicillin flasks and lyophilized for 18-20 hrs in IZ-9 (CSR) or similar equipment at the maximum temperature of the product 5 degrees C. Lyophilized reagent is a white or slightly cream-colored powder. It retains its activity for at least a year as evidenced by the activated partial thromboplastin time test. The range of activities within one lot is less if commercial lyophilized donor reference plasma is used in the test. The reagent is stored in a refrigerator at 4-8 degrees C.

Blood Coagulation Tests↗
PubMed1990

[Lyophilized plasma for use in calculating the activity of the prothrombin complex factors].

Soviet lyophilized donor reference plasma (a reagent), intended for plotting a calibration graph or for calculating the activities of prothrombin factors (index) according to a formula, is stable for 12-14 months. It is fit for the aforesaid purposes with the blood plasma of both donors and patients suffering from various degrees of the studied procoagulant deficits.

Adolescent↗
PubMed1990

[Evaluation of single-stage methods of studying the activity of factor VIII].

Accurate diagnosis of coagulopathies related to changed factor VIII activity, studies of specific activities of antihemophilic cryoprecipitate globulin used for hemostatic correction in patients, and monitoring of therapy efficacy are impossible without a reproducible, sensitive, standard, and available method. The authors have compared two single-stage methods developed by Soviet scientists: that by V. P. Baluda et al. and that by L. P. Papayan and P. V. Khrolova. Both methods have proved sufficiently sensitive and capable to detect factor VIII deep deficiency, but L. P. Papayan and P. V. Khrolova's modification was found higher reproducible, and therefore chosen for further investigation in order to standardize it. Besides the conditions of reproducing the method, reference plasma, substrate plasma deficient for factor VIII, and partial thromboplastin are to be standardized.

Evaluation Studies as Topic↗
PubMed1989

[Evaluation of methods of studying hemostasis].

Comparative assessment of the methods for studies of platelet aggregation, used in the USSR and in Hungary, has demonstrated the usefulness and reproducibility of both. The reagents manufactured by Reanal (Hungary) are characterized by a higher sensitivity, inducing a more distinct and rapid formation of aggregates. This fact is of particular importance when no aggregometers are available and the 'snow whirl' is assessed visually. Another advantage of the Hungarian aggregants is the presence of the whole set of reagents in the kit and standardization of these reagents. Assessment of the activated partial thromboplastin time of mixed donor native plasma with the use of the Soviet native partial thromboplastin stored frozen and with the use of the Reanal reagent has demonstrated a high variability of the results; this may be explained by the employment of nonstandard reference plasma. The advantages of the imported lyophilized reagent are a year's shelf life and the possibility of transportation.

Blood Coagulation Tests↗