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M Stajić

Publications and source records attributed to M Stajić.

At least 37 records · Page 2Linked to original sources
PubMed1979

Detection of drugs using XAD-2 resin. I:Choice of resin, chromatographic conditions, and recovery studies.

Amberlite XAD-2, a nonionic polystyrene divinylbenzene resin, was first used for the analysis of drugs in urine and a number of reports have described the development at optimal conditions for extraction, including type of resin columns, pH conditions, and eluting solvents. XAD-4 and XAD-7 resins were compared to the similarly structured XAD-2 resin and no significant advantage over the XAD-2 resin for drug screening was observed. A quantity of 5 to 6 g of resin was found to have sufficient capacity for the extraction of 200 ml of pentobarbital solution (1 mg/100ml). A column flow rate of approximately 15 ml/min (gravitational flow) was sufficient for analysis and slower rates were not more efficient. A mixture of ethyl acetate and 1,2-dichloroethane (3:2) was found to give best overall recovery (66 to 94%) of drugs, the resulting extracts being reasonably free of interfering substances. A pH value of 8.5 is recommended as optimum for comprehensive analysis of acidic and basic drugs. Recovery studies were conducted on spiked samples to determine drug losses occuring during various steps in the XAD-2 extraction procedure for four acidic (amobarbital, secobarbital, pentobarbital, and phenobarbital) and four basic (morphine, codeine, meperidine, and methadone) drugs. A relatively small amount (0 to 5%) of the drugs was not adsorbed by the resin and amounts varying from 6 to 40% failed to be desorbed by the eluting solvent. Additional losses occurred during the removal and analysis of TLC spots. Recovery of drugs from aqueous solutions analyzed with the XAD-2 resin were compared to recoveries reported in the literature with other XAD-2 resin methods for the extraction of drugs from urine. Recovery of phenobarbital, morphine, and codeine improved by 4 to 23% while recoveries of amobarbital, pentobarbital, secobarbital, methadone, and meperidine were 4 to 28% less efficient when compared to literature data.

Barbiturates↗
PubMed1979

Detection of drugs using XAD-2 resin. II:Analysis of liver in medical examiner's cases.

Liver tends to concentrate drugs in quantities generally higher than those found in blood or other body compartments. This fact as well as the general availability of liver in postmortem cases makes it an important specimen for comprehensive toxicologic investigation. A scheme for the analysis of liver for drugs with tissue hydrolysis, XAD-2 resin extraction, and TLC has been developed and the parameters affecting recovery have been studied. The hydrolysis of liver specimens at various pH conditions resulted in an improved recovery for morphine by using pH 2 (2N hydrochloric acid). Recoveries of barbiturates, codeine, and meperidine were essentially the same at pH 2 and pH 3. A considerable loss (22 to 55%) was observed for four drugs (pentobarbital, morphine, codeine, and meperidine) as a result of drug binding to the tissue pellets during the process of centrifuging the liver homogenates. This method is recommended as a comprehensive screening procedure for drugs in liver tissue. For quantitative purposes, however, it is necessary to determine a correction factor for all the losses occurring at the various steps of the procedure. This procedure compared favorably with other procedures for liver analysis reported in literature.

Barbiturates↗
PubMed1979

Detection of drugs using XAD-2 resin. III:A routine screening procedure for bile.

The ability of bile to concentrate drugs and metabolites coupled with its general availability make it suitable for analysis and often the fluid of choice in postmorten cases requiring drug screening. Bile (5 to 10 ml) was diluted with water, sulfuric acid was added, and the mixture was autoclaved. The precipitated bile salts were easily removed by filtration and the filtrate (pH adjusted to 8.0 to 8.5) extracted with XAD-2 resin. Drugs were eluted with a mixture of ethyl acetate/1,2-dichloroethane and analyzed with thin-layer chromatography. Varying the dilution of bile improved the recovery of morphine, codeine, methadone, amobarbital, and phenobarbital. Excessive dilution, however, caused a washing phenomenon and reduced recovery of some drugs, as shown with morphine and codeine. The procedure described is useful for the rapid screening of bile specimens for drugs.

Barbiturates↗
PubMed1978

[Transfusion of leukocytes and platelets in the treatment of acute leukemia].

Supportive therapy of concentrated leukocytes and platelets has no obvious significance. In the paper authors presented the methods of separation of concentrated leukocytes and platelets, investigation of number and functional abilities of preserved leukocytes and platelets as well as the monitoring of the transfusion effect in the patients with acute myeloblastic leukemia. Special attention was paid to the separation of blood cells by the cell centrifuge with continuous flow. Side effects after leukocytes and platelet transfusion was monitored -- occurence of the sensibilization to the HL-A antigens. For the detection of HL-A antibodies two-stage microlymphocytotoxic test was used for the investigation of patient's serum; for the application of leukocyte and platelet transfusion we used cross-match test between donor's lymphocytes and patient's serum in progressive dilution. In the paper authors discussed the correlation between the appearance of HL-A antibodies and the number of given transfusions.

Blood Transfusion↗
PubMed1977

[Diagnosis of von Willebrand's disease].

Diagnosis and differential diagnosis of von Willebrand's disease was a special problem. Criteria up to date: prolonged bleeding time, reduced platelet adhesiveness, decreased F. VIII coagulant activity, as well as a particularly behaviour after the infusion of F. VIII, were not sufficient to differentiatie this disease from other congenital disorder of F. VIII. Recent investigations, introducing the immunological methods for determination of F. VIII--related antigen, as well as the investigation of ristocetin induced platelet aggregation, give the new approach in the diagnosis of von Willebrand's disease. Authors presented preliminary results of investigations of F. VIII--related antigen in the patients with von Willebrand's disease, as well as the results of investigation of the patients with hemophilia A and normal subjects, as a control group.

Adult↗
PubMed1976

[Concentrated antihemophilic globulin in the treatment of hemorrhagic syndromes].

The author presented the general informations on the preparation of the Factor VIII and Factor IX concentrates, on their use and side effects. Special attention was paid to the resolutions of the Scientific group on the Inherited Blood Clotting Disorders, in the meeting of the World Health Organization, which was held in Geneva, 1972.

Afibrinogenemia↗
PubMed1976

[Substitution therapy in the treatment of acute leukoses].

In the treatment of acute leukoses, from the first onset of the disease till the occurrence of the first remission, as well as in the course of intesive hemiotherapy, the substitution therapy by blood derivatives has the great importance. Anaemia, granulocytopenia, hypoproteinaemia and hemorrhagic syndroms, caused by thrombocytopenia, liver diseases and disseminated intravascular coagulation, are the most frequent disorders requiring the substitution therapy. Authors presented the advantages of the substitution therapy by blood derivatives upon the whole blood.

Acute Disease↗
PubMed1975

[Experiences at the Blood Transfusion Center of the Socialist Republic of Serbia in providing aimed transfusions].

The development of modern medicine causes the more and more needs of blood in providing the complete health care of the patients. The increased need can be satisfied only by the rational use of blood on the principle of selective transfusions. In this work our present possibilities are given, in the separations of certain blood components, their good and bad effects, as well as the indications for use in some pathological states.

Blood Platelets↗