[From a scientific idea to clinical use]. / Od naucne ideje do klinicke primene.

INTRODUCTION: In the nineteenth century, medicine, a former empiric skill, obtained its scientific basis owing to the development of physics, chemistry, biology, physiology, histology, biochemistry and other natural sciences. Fast progress in medicine was thus possible, but at the same time made the introduction of new scientific ideas into clinical use very difficult and therefore majority of them never reach satisfactory clinical application. Two examples from the author's own experience are presented here. FROM RADIOACTIVITY TO NUCLEAR MEDICINE: Soon after the discovery of radioactivity, George Hevesy gave a scientific basis for its use as a diagnostic and therapeutic tool in medicine. The first nuclear medicine laboratory was established in Vojvodina in 1963 and during the following twenty years, clinical application of radioactive tracers was developed very successfully in this area. But in the subsequent years the use of nuclear medicine methods declined dramatically for many reasons, mainly because of unsatisfactory cost/benefit ratio. FROM EXPERIMENTAL BLEEDING TO ERYTHROPOIETIN: The scientific idea of humoral regulation of hematopoiesis was proposed by Carnot at the beginning of the twentieth century, but it was introduced for clinical application only a hundred years later. It became possible by pharmaceutical production of recombinant hematopoietic growth factors by genetic engineering, and some of them, erythropoietin and granulocyte CSF, are available at high prices. They were used successfully for anemia in renal failure and some cases of neutropenic syndrome respectively, but compared to the initial expectations and quantity of research invested this is an unsatisfactory result. INSTEAD OF CONCLUSION: The introduction of these two presented scientific ideas into clinical application failed because of inadequate organization of medical scientific research and lack of financial support.

Effect of serum from thrombocytopenic patients on platelet count in blood of mice.

Estimation of the effect of sera obtained from patients suffering from several forms of megakaryocytic (immune) thrombocytopenia (19), and those with acute non-lymphoblastic leukemia (13), on the platelet count in the peripheral blood of mice was carried out. Several groups of mice were injected intravenously with 0.2 ml of patients' sera, and the platelet count was followed up for 10 days. A marked and highly significant decrease of platelet count in recipient mice was established even 6 hours after the application of both groups of patients' sera. In the control group of mice receiving pooled serum of healthy persons this decrease was not registered. It can be presumed with great probability that the mechanism of development of thrombocytopenia in both groups of patients is very similar: there is an extremely increased destruction of platelets in the peripheral blood in cases with immune thrombocytopenia by antibodies, and in cases with acute leukemias by antibodies and/or other cytotoxic substances. In further investigations the influence of thrombopoietin on this phenomenon will be tested.

[Clinical use of thrombopoietin (c-Mpl Ligand)]. / Klinicka upotreba trombopoetina (c-Mpl LIGANDA).

INTRODUCTION: Results in clinical use of thrombopoietin have been published later than of other hematopoietic growth factors, because until recently the research was the least understood aspect of blood cell development. Reasons for this time gap were numerous, from inconvenient methods for measurement of thrombopoietin activity, to difficulties of its chemical purification. It is claimed recently that the understanding of platelet production has been profoundly advanced by the recombinant-gene synthesis and characterization of c-Mpl ligand (Megakaryocyte Growth and Development Factor), a substance which strongly enhances the proliferation of megakaryocytic line and the production of platelets. In this paper, some historical facts and biology of thrombopoietin are briefly discussed as well as the recent of the clinical use of thrombopoietin. THE HISTORY OF RESEARCH AND PRODUCTION OF THROMBOPOIETIN: The concept that the platelet production is underlying humoral regulation was first promoted by a group of Hungarian authors and they also named that humoral regulator--thrombopoietin. Further research followed in several countries including our own, and the initial studies proved that the serum of thrombocytopenic animals induced proliferation and maturation of megakaryocytic cell line and thrombocytosis in the peripheral blood of recipient animals. Later, when in vitro techniques were developed, it was shown that this humoral regulator has also a colony stimulating activity on megakaryocytic precursors. During the following two decades, studies of megakarycytopoiesis supported the hypothesis that two types of factors are involved in platelet production: early acting--megakaryocyte colony stimulating factors (Meg-CSF), and late acting--megakaryocyte potentiators, first of all thrombopoietin (TPO). However, extensive attempts on the purification of substances that either stimulate megakaryocyte development or augment platelet production failed to yield a homogeneous protein adequate for protein sequencing and cDNA cloning, the usual route which led to the production of other hematopoietic growth factors. Furthermore, a large number of other cytokines were described that possessed activity in various assays of megakaryocyte development. In spite of great number of accumulated data, it seemed in early 1990s that the production of a distinct, clinically useful lineage specific thrombopoietin will not be soon possible to achieve. The breakthrough occurred in 1994, when four groups of investigators published simultaneously their successful results on production of c-Mpl ligand, a substance which specifically binds to the Mpl receptors on megakaryocytes and has a very potent thrombocytopoietic effect. This production is based on genetic engineering and two companies (Kirin and Amgen) are already able to produce recombinant human thrombopoietin in large amounts, for clinical use. Although this substance is not commercially available yet, it passed the preclinical and clinical trials whose results are presented here. RESULTS OF THE PRECLINICAL TRIALS OF RECOMBINANT THROMBOPOIETIN: The chemical structure of human recombinant thrombopoietin (rTPO) is well defined, it is a glycoprotein consisting of 353 amino acids and molecular weight of 30 kD. The biologic actions of this molecule are in vitro: stimulation of megakaryocyte colony forming, endoreduplication of chromosomes and megakaryocyte maturation, and in vivo: increase of the number of progenitors and of megakaryocytes in the bone marrow, and an extensive elevation of platelet count in the peripheral blood 4-7 days after its application. Also, in synergism with other pluripotent cytokines, it can stimulate the proliferation of other progenitors including CD34+ stem cells. Based on these data it is considered that c-Mpl ligand is the main physiological humoral regulator of thrombocytopoiesis, having the biological actions both of MegCSF and TPO.

[Clinical use of granulocyte colony stimulating-factors (GM-CSF and G-CSF]. / Klinicka upotreba faktora stimulacije granulocitnih kolonija (GM-CSF i G-CSF).

Humoral regulation of granulocytopoiesis was proven 30 years ago by discovery of factors which stimulate production of granulocyte colonies (CSF-colony stimulating factors), while clinical utilization of recombinant human colony stimulating factors (rhGM-CSF and rh-CSF) is present for the last 10 years. On the basis of this, today we have a lot of experience in regard to indications, modes and results of their clinical utilization. Clinical utilization of CSF is divided into three fields: treatment of the neutropenic syndrome, utilization in oncologic patients and in bone marrow transplantation. The best results have been achieved in neutropenic syndrome therapy, both chronic (congenital, cyclic and idiopathic neutropenia, aplastic anemia and myelodysplastic syndrome) and acute (granulocytopenia drug induced, postirradiation neutropenia). In oncologic patients it is used to eliminate neutropenia which occurs after cytostatic therapy with standard doses or high dose cytostatic therapy with better effects on the tumor, but with myeloablation. Granulocyte colony-stimulating factor is also used for stimulating fast granulocytopoiesis in autologous or allogeneic bone marrow transplantation, in unsatisfactory transplants especially. In recent years it has been used for mobilization of progenitor CD34+ cells in the donor in order to perform their transplantation, especially in treatment of chronic myeloid leukemia. At our institution G-CSF has been successfully used in 17 patients.

[The role and achievements in clinical pathophysiology in the Novi Sad region]. / Mesto i dostignuca klinicke patofiziologije u nasoj sredini.

Nowadays, clinical pathophysiology in our conditions is a firmly founded branch of medicine which has had an important role in the improvement of diagnostics, scientific and researching work and all forms and levels of education at the Medical Faculty in Novi Sad. The value and usefulness of clinical pathophysiology has been particularly important in the team work within the Clinical center in Novi Sad in the time it was organized as an unique health care institution. Pathological physiology was ready to take over all its tasks foreseen within this type of organization, and through further constructional and equipment improvements it could soon achieve European standards in its work. Professionally unjustified decision for abandoning the concept of Clinical center in Novi Sad has greatly affected health care service in general. Twenty years of work on the improvement of pathophysiology have been thrown away and its important role in the first-class treatment of the patients has been certainly discredited but not denied. If health care service happens to be reorganized following the model of developed countries there will be a chance for the revitalization of clinical pathophysiology and finalization of its development to fulfill the interests of patients for obtaining the high quality treatment in our conditions.

[Clinical use of erythropoietin]. / Klinicka upotreba eritropoetina.

Humoral regulation of erythropoiesis has been known for 100 years, while clinical utilization of recombinant human erythropoietin (rhEPO) only for two decades. It can be said that there is much experience in regard to indications, models and results of its clinical utilization. According to the standpoint of secretion of erythropoietin, anemias can be divided into those where secretion is increased and satisfactory, those where it is increased but not satisfactory and into those where it is not increased or it is even decreased. Anemias of the first group are not an indication for rhEPO utilization, the second group is relative and the third group absolute indication for its utilization. The best results are achieved with absolute indications and it is anemia in chronic renal insufficiency and nonphysiologic anemia of premature babies. Good results can be expected, but not predicted in relative indications, such as anemias in chronic infections, anemias in malignant diseases, myelodysplastic syndrome, aplastic anemia and other secondary anemias. Utilization of rhEPO is useful also in certain states without anemia, especially in transfusiology.

[Clinical use of hematopoietic growth factors--general principles]. / Klinicka upotreba hematopoeznih faktora rasta--opsti principi.

Biology of haematopoietic growth factors in the process of haematopoiesis is well known, but their clinical utilization started with production of recombinant preparations. Today only preparations of Erythropoietin, GM-CSF and G-CSF are commercially at disposal. Absolute indications for utilization of haematopoietic growth factors are states caused by decreased production of certain classes of blood cells as a consequence of shortage of a growth factor necessary for production of a certain class. As these states are very rare, relative indications spread to other states characterized by a decreased number of blood cells or necessity for stimulation of haematopoiesis due to any other reason. This paper contains results of clinical researches only for those growth factors which are not commercially utilized.: M-CSF, Interleukin 3, PIXY321, SCF, Interleukin 6, Interleukin 11, Interleukin 1, Interleukin 2 and Thrombopoietin. Our institution utilizes only the preparations of Erythropoietin (Eprex) and G-CSF (Neuprogen) in 38 patients.

[The effect of blood from patients with idiopathic thrombocytopenia and thrombopoietin on the thrombocyte count in the blood of mice]. / Uticaj seruma osobe obolele od idiopatske trombocitopenije i trombopoetina na broj trombocita u krvi misa.

We examined effects of serum belonging to persons suffering from chronic autoimmune thrombocytopenia on the number of thrombocytes in the peripheral blood of mice. The serum, 0.2 ml, was given to groups of mice intravenously and then the number of thrombocytes was examined during 14 days. A significant decrease of thrombocytes was established in mice receivers during the period of 6 hours to 12 days (it was maximal from the 4th to the 6th day). The same serum was given to two groups of mice and then one of them was also given thrombopoietin preparation. The number of thrombocytes was established 4 and 6 days later and in the group where only serum was given there was a significant decrease of thrombocytes. In the group where thrombopoietin was given apart from the serum, the number of thrombocytes remained normal. On the basis of these findings it has been suggested that, using such an experimental model, a biological in vivo test could be made to demonstrate antibodies in autoimmune thrombocytopenias and to establish that thrombopoietin could be a useful drug in cases of chronic autoimmune thrombocytopenia.

[Blood of patients with acute leukemia increases the leukocyte count in the peripheral blood of mice]. / Serum bolesnika obolelih od akutne leukemije povecava broj leukocita u perifernoj krvi miseva.

Serum of 23 patients suffering from acute myeloid leukemia were given to groups of six mice (s.c. 0.6 ml); 3 and 5 days later the total number of leucocytes, granulocytes and lymphocytes was determined in the peripheral blood of mice. Serums of all patients caused significant increase of leucocytes in mice 3 and/or 5 days after the serum's application. In most cases the increase was caused by increased number of granulocytes and lymphocytes, and in 6 cases only by increase of granulocytes or only lymphocytes. This increase can also be thought of as a stimulation of leukocytopoiesis by increased concentration of hematopoetic growth factors in blood of those suffering from acute leukemia.

[Use of radionuclide quantitative analysis in routine diagnosis of metabolic bone diseases]. / Primena radioizotopskih kvantitativnih analiza u rutinskoj dijagnostici metabolickih bolesti kosti.

Global and regional quantity indexes of metabolic bone activities are determined on the basis of given scintigraphic dose for skeleton examination. The calculation of all analyzed indexes was carried out in all cases of the control group and patients with established disturbance of bone tissue metabolism. When choosing the method used in the routine work, apart from diagnostic value of analysis numerous criteria have been respected. The analyzed global quantity indexes of metabolic bone activity adapted to conditions of routine work have similar diagnostic value, while the best regional index relating bone soft tissue is the one concerned with the upper leg. As the examined quantity indexes enable more reliable interpretation of the scintigraphic findings, in everyday work the scintigraphic examination should be filled in by determination of corrected retention of activity in the whole body and calculation of radiosotope analysis significantly depend one the kidney function and urine elimination.

[The work of the Serbian Medical Society--the Medical Society of Vojvodina under present conditions]. / Rad Srpskog lekarskog drustva--Drustva lekara Vojvodine u savremenim uslovima.

The content of work of medical society in Vojvodina has always been primarily set by the founder with its main goal: the physicians professional and scientific specialization. In recent years there have been many socio-political, moral and social changes which have had great influence on the work of medical organizations. The poverty of the whole society, especially of the health service, has completely disabled organization of big professional meeting so that the professional activity meant mostly one-day meetings in health institutions. Although there was a threatening possibility to stop publishing the professional journal "Medical Review" after 47 years of appearing in print, today problem is solved by financial help by the government. Apart from professional work, other activities of physicians organizations are becoming important today. An appropriate attitude toward war generally speaking was declared in 1992 as an "Appeal for Peace". A request was made to distinguish profession and politics in the work of physicians so that the society acted only as a professional organization without political involvement and there is an initiative to found a medical association. Physicians gave their best in this hard situation to maintain work of the health service, but as it was not possible any more at one moment, an extra congress of physicians of Serbia was organized verifying serious consequences of war considering the health of the whole population. Society has been extremely engaged in solving numerous problems of ethics which have appeared due to war such as lack of medicines and health care materials as well as abuse of the private medical practice.

Usage of quantitative static scintigraphy of the thyroid gland in defining the therapeutical dose of radioiodine.

In a group of 21 patients sent by endocrinologist for antihyperthyreosis therapy with radioactive iodine, we calculated and compared the weight of the thyroid gland by quantitative static scintigraphy, using two computed parameters--according to surface and volume of the gland. Statistically we came to the conclusion that weight of the thyroid gland calculated on the basis of surface gives significantly higher values than calculation by the use of volume. The calculation of weight of the thyroid gland using the surface of scan image is recommended, while quantitative static scintigraphy increases the standardisation of the procedure very much.

[The importance of intact parathyroid hormone determination in the evaluation of parathyroid gland function]. / Znacaj odredivanja intaktnog paratireoidnog hormona u proceni funkcije paratireoidnih zlezda.

The study investigates the importance of determining the intact parathormone in the evaluation of parathyroid gland function in different conditions of change in their function and the alteration of parathormone metabolism: primary and secondary hyperparathyroidism, hypoparathyroidism and hyperthyroidism. The role and place of intact parathormone determination in routine diagnostic schemes of calcium homeostasis disorders was reviewed by the simultaneous determination of the indicators of calcium and bone metabolism and other calcium homeostasis hormone regulators, as well as the C- and N-terminal parathormone fragments and by establishing their mutual links with the values of the intact parathormone.

[Quantitative static scintigraphy of the thyroid gland]. / Mogucnosti kvantitativne staticke stintigrafije stitaste zlezde.

The paper describes a static scintigram computer processed by the Siemens-Euromeni method which gives rather accurate parameters concerning the overall functional thyroid tissue mass, as well as functions of a certain thyroid gland node. It facilitates the calculation of the dimensions of the right-angled field which borders the thyroid gland (cm), radioactivity uptake (% of a given dose) in the whole gland, left and right lobe, the ratio between the left and right lobe uptake, the surface (cm2) of the whole gland and of the left and right lobe, the ratio between the left and right lobe surfaces, the number of impulses (imp) registered in the whole gland and in the left and right lobe, the volume (cm3) of the whole gland and of the left and right lobe, the ratio between the left and right lobe volume, as well as the surface and radioactivity uptake (% of a given dose and % of the total uptake) in the marked nodes. An additional calculation could offer an uptake ratio per surface unit between the node and paranodal tissue which, by the use of suppression tests offers a very accurate assessment of the function and compensation of each node. The method represents a significant contribution to an accurate assessment of the functional mass as well as to the assessment of nodal changes of the thyroid gland.

[Radioimmunologic determination of growth factors. II. Comparative development of methods for the determination of hematopoietic growth factors]. / Radioimunolosko odredivanje faktora rasta. II. Uporedni razvoj metoda za odredivanje hematopoeznih faktora rasta.

On the basis of our long-term experience, presented are the current clinically useful methods for determining erythropoietin, the granulocytopoiesis growth factor and thrombocytopoietin with the results in their use. Facts are shown, concerning the long-used method of determining erythropoietin through the use of the biological test on polycythemic mice. In our conditions, mice treated with physiological solution (negative controls) have a Fe-59 incorporation below 0.5% of the given dose, while 0.2 units of the international erythropoietin standard (positive control) increases that incorporation to 3.0%. Also presented, are results of determining erythropoietin by means of the newest immunometric method which has shown exceptional features: the whole procedure, including necessary rinsings, lasts about six hours, and it is possible, in the course of one work day, to all at once precisely determine the erythropoietin concentration in 80 samples of human serum. This fact, as well as the outstanding sensitivity of the method which is about 2 mJ/ml (that is 50 times the sensitivity of the biological test) has as a result, the wide introduction of erythropoietin determination in the clinical use of today and the definition of its clinical importance. The measurement range of the method is from 2-200 J/L which can be extended further by specimen dilution. It is especially important that duplicate measurements at one point of the curve almost coincide, which indicates great method precision. The lowest measured concentration in our series amounted to 0 J/L and the greatest to greater than 250 J/L. Elevated values were found in 17 of the 114 serums.(ABSTRACT TRUNCATED AT 250 WORDS)

[Significance of highly sensitive (immunoradiometry assay) TSH in the evaluation of hypothalamo-hypophyseal-thyroid axis function]. / Znacaj visokoosetljivog (IRMA) TSH u proceni funkcije hipotalamo-hipofizno-tireoidne osovine.

A diagnostic value of immunoradiometric TSH assay in the evaluation of the function of hypothalamo-hypophyseal-thyroid axis was investigated in this paper. Normal values of basal TSH and TSH response during TRH test were determined by the use of ROC analysis. It was found out that there was a highly significant correlation between basal TSH and the responses during TRH test and that the diagnostic value of basal TSH in the evaluation of function of thyroid axis was almost identical to the diagnostic value of responses during TRH test. This finding pointed to the fact that basal TSH determination could replace the application of TRH test in diagnostic of thyroid axis disturbances. Comparing diagnostic value of basal TSH with other tests which served for the confirmation of thyroid axis disturbances, this test proved to be dominant, the most specific and the most sensitive in respect to other applied tests and could be regarded as the first step in diagnostic scheme of thyroid disturbances.