Correlation of the mineralization rate index in the forearm after intravenous and oral application of 47Ca

U ovom radu željeli smo ispitati, da li način primjene radioaktivnog kalcija utječe na određivanje indeksa brzine mineralizacije (aF). Indeks brzine mineralizacije podlaktice odredili smo na 13 ispitanika od kojih je pet primilo radioaktivni kalcij (47Ca) intravenski, a osam oralno. Rezultate obih skupina usporedili smo s brzinom mineralizacije podlaktice izračunatom na osnovi radioaktivnog stroncija (85Sr), koji su svi ispitanici primili intravenski. Statistička obrada rezultata pokazala je da nema značajne razlike u indeksu brzine mineralizacije između dva načina primjene radioaktivnog kalcija.In the present preliminary communication we wanted to find out whether the way of application of radioactive calcium influences the determination of the index of mineralization rate ar. The index of mineralization rate in the forearm was determined in 13 subjects, of whom 5 received radioactive calcium intravenously and 8 orally. The results obtained in the two groups were compared with the mineralization rate in the forearm calculated on the basis of radioactive strontium (85Sr), which was administered in the same experiment intravenously. A statistical evaluation of the results showed that there exists no significant difference concerning the index of mineralization rate obtained with either way of isotope application. Besides there is a tendency to obtain lower values with 85Sr compared to those obtained with 47Ca

Coagulation activity of stored blood at +4°C

U ovom je radu ispitana koagulaciona aktivnost uskladištene krvi na +4°C. Primijenjeno je osam koagulacionih testova, a promjene koagulacione aktivnosti prikazane su grafički. Testiranje je izvršeno odmah nakon vađenja krvi, te drugi, sedmi i četrnaesti dan. Rezultati autora uspoređeni su s rezultatima iz literature.The coagulation activity of blood stored at 4°C was investigated. Eight different clotting tests were used. The changes in the coagulation activity are presented graphically. The testing was performed .immediately after the blood was taken from the vein and then after the first, seventh and forteenth day of storage. The authors compare their results with the data reported in literature. On each figure the time of storage in days is marked on the abscissa. The ordinate indicates the clotting time in sec. (Fig. 1), the prothrombin time in sec. (Fig. 2), the prothrombin consumption test in sec. (Fig. 3), the number of platelets x 10-3 (Fig. 4), the tromboplastin generation test, % activity (Fig. 5), the antihemophilic globulin % (Fig. 6), factor V activity % (Fig. 7), factor VII activity % (Fig. 8)

Electrophoretic investigation of the plasma calcium transportation

Elelotroforetskim metodama ispitivana je uloga proteina plazme u transportu kalcija. Plazma je bila 12 sati inkubirana s radioaktivnim kalcijem kod 37° C. Elektroforeza označene plazme vršena je u barbituratnom mediju, diskontinuiranom i kontinuiranom tehnikom. Metodom ultrafiltracije određivana je količina radioaktivnog kalcija vezanog na proteine plazme. Diskontinuiranom elektroforezom vršena je separacija radioaktivnog kalcija u plazmi, ultrafiltratu i ugušćenoj plazmi koja zaostaje nakon ultrafiltracije. Elektroforeza je·rađena uz jakost polja od 7 V/cm u vremenu od 2 sata, tako da se na elektroforetskoj traci nalazi i zona kalcija koja odgovara ionskom kalciju. U proteinskoj zoni zaostaje znatno manje kalcija nego što odgovara proteinski vezanom kalciju dobivenom metodom ultrafiltracije. Kontinuiranom elektroforetskom tehnikom dobiveni su slični rezulltati. U ovom radu primijenili smo i jednu modifikaciju metode za ispitivanje transporta kalcija na proteinima plazme. U toku kontinuirane elektroforeze u barbituratnom mediju putovala je, naime, preko separiranih zona proteina zona kalcija-45. U određenim uvjetima ispitivanja pokazalo se da u transportu kalcija mogu sudjelovati albumini, beta i gama globulini.The role of plasma proteins in the calcium transportation was studied with electrophoretic methods. The plasma was 12 hours incubated with radioactive calcium at 37°C. Labelled plasma electrophoresis was carried out in the barbiturate medium with the aid of discontinual and continual technique. The amount of plasma protein bound radioactive calcium was determined by the method of ultrafiltration. Separation of radioactive calcium in plasma, in ultrafiltrate and in the concentrated ultrafiltration residue was carried out by the discontinued electrophoresis. Electrophoresis was performed at the field intensity of 7 V/cm in the period of 2 hours so that the zone of calcium corresponding to ionized calcium was also found on the electrophoretic band. In the zone of proteins considerably less calcium was retained than it would have corresponded to the protein hound calcium obtained by the method of ultrafiltration. Similar results were obtained by the technique of continual electrophoresis. In this work a modification was also applied of the method for study of plasma protein calcium transportation. In the course of continual electrophoresis in the barbiturate medium over the separated zones of proteins has, namely, run the zone of calcium-45. At the determined condition of the study it was shown that albumins, beta and gama globulins may take part in the transportation of calcium

Kinetika radioaktivnog kalcija (47Ca) kod čovjeka

Kinetics of 47Ca was investigated in 9 healthy subjects. In this paper slight modifications of the Wenderberg method were applied. Our modification of the method is technically simpler, giving equally valuable results. The following values were obtained: Accretion: 0.57 ± 0.12 g Ca/day, S compartment: 2.10 ± 0.32 g Ca and E compartment: 2.86 ± 0.83 g Ca.U devet zdravih osoba ispitivana je kinetika radioaktivnog kalcija. U svom radu primijenjene su manje modifikacije Wendebergove metode. Te modifikacije pojednostavljaju ispitivanja a daju jednako vrijedne rezultate. Dobivene su ove vrijednosti: akrecija: 0.57 ± 0.12 g Ca/dan, S prostor: 2.10 ± 0.32 g Ca i E prostor: 2.86 ± 0.83 g Ca

Procenjivanje metode rotacije uzorka u mjerenju gama aktivnosti velikih nehomogenih uzoraka biološkog materijala

The sample rotation method was evaluated with an instrument partly constructed at the Institute for Medical Research and Occupational Health. The purpose of our investigation was to find the optimal compromise between the sensitivity of \u27the instrument and the measuring error due to the inhomogeneity of the sample. The method was evaluated with 85Sr and 47Ca. On the basis of our experimental data we conclude that for the determination of radioactivity in large samples of biological material a relatively modest instrument accessible to all clinical radioisotope operating institutions can be used.Evaluirali smo metodu rotacije za mjerenje radio-aktivnosti velikih uzoraka biološkog materijala uređajem djelomično konstruiranim na Institutu za medicinska istraživanja i medicinu rada. Cilj rada bio je naći optimalni kompromis između osjetljivosti mjerenja i mjerne pogreške uvjetovane nehomogenošću uzorka. Valjanost metode provjerena je određivanjem aktivnosti 85Sr i 47Ca. Na osnovi naših rezultata može se doći do zaključka da za određivanje radio-aktivnosti velikih uzoraka biološkog materijala mogu poslužiti relativno skromne aparature pristupačne svim kliničkim ustanovama, koje rade s radioizotopima

Electrophoretic investigation of the plasma calcium transportation

Elelotroforetskim metodama ispitivana je uloga proteina plazme u transportu kalcija. Plazma je bila 12 sati inkubirana s radioaktivnim kalcijem kod 37° C. Elektroforeza označene plazme vršena je u barbituratnom mediju, diskontinuiranom i kontinuiranom tehnikom. Metodom ultrafiltracije određivana je količina radioaktivnog kalcija vezanog na proteine plazme. Diskontinuiranom elektroforezom vršena je separacija radioaktivnog kalcija u plazmi, ultrafiltratu i ugušćenoj plazmi koja zaostaje nakon ultrafiltracije. Elektroforeza je·rađena uz jakost polja od 7 V/cm u vremenu od 2 sata, tako da se na elektroforetskoj traci nalazi i zona kalcija koja odgovara ionskom kalciju. U proteinskoj zoni zaostaje znatno manje kalcija nego što odgovara proteinski vezanom kalciju dobivenom metodom ultrafiltracije. Kontinuiranom elektroforetskom tehnikom dobiveni su slični rezulltati. U ovom radu primijenili smo i jednu modifikaciju metode za ispitivanje transporta kalcija na proteinima plazme. U toku kontinuirane elektroforeze u barbituratnom mediju putovala je, naime, preko separiranih zona proteina zona kalcija-45. U određenim uvjetima ispitivanja pokazalo se da u transportu kalcija mogu sudjelovati albumini, beta i gama globulini.The role of plasma proteins in the calcium transportation was studied with electrophoretic methods. The plasma was 12 hours incubated with radioactive calcium at 37°C. Labelled plasma electrophoresis was carried out in the barbiturate medium with the aid of discontinual and continual technique. The amount of plasma protein bound radioactive calcium was determined by the method of ultrafiltration. Separation of radioactive calcium in plasma, in ultrafiltrate and in the concentrated ultrafiltration residue was carried out by the discontinued electrophoresis. Electrophoresis was performed at the field intensity of 7 V/cm in the period of 2 hours so that the zone of calcium corresponding to ionized calcium was also found on the electrophoretic band. In the zone of proteins considerably less calcium was retained than it would have corresponded to the protein hound calcium obtained by the method of ultrafiltration. Similar results were obtained by the technique of continual electrophoresis. In this work a modification was also applied of the method for study of plasma protein calcium transportation. In the course of continual electrophoresis in the barbiturate medium over the separated zones of proteins has, namely, run the zone of calcium-45. At the determined condition of the study it was shown that albumins, beta and gama globulins may take part in the transportation of calcium

Kinetics of radioiodine elimination

Na osnovi matematičkih rješenja vlastitog kinetičkog modela sa šest odjeljaka izučavali smo eliminacionu kinetiku radiojoda. Ispitali smo neke mogućnosti ubrzanja eliminacije radiojoda. To su: potpuni blok ulaza joda u štitnjaču, blok organifikacije joda u štitnjači, povećanje bubrežnog klirensa za jodide i ubrzavanje izlučivanja organskog joda iz štitnjače. Izgleda da bi bilo najjednostavnije blokirati ulazak joda u štitnjaču. Blok organifikacije joda u štitnjači također je vrlo djelotvoran način ubrzanja eliminacije. Preostale dvije mogućnosti, koje smo razmatrali, mogle bi samo iznimno doći u obzir, jer ti postupci ne bi bili tako efikasni.Applying mathematical solutions of our own six-compartment model of iodine kinetics we studied radioiodine elimination and examined certain possibilities of enhancing it. These were: the complete blocking of the thyroid iodine uptake, the blocking of iodine binding in the thyroid, increased renal clearance for iodides and faster elimination of organic iodine from the thyroid. The simplest seems to be the blocking of iodine entry into the thyroid. The blocking of iodine binding in the thyroid is also a very efficient way of enhancing elimination. The other two possibilities could be taken into account only exceptionally, as they would not be equally efficient

Plant assemblages respond sensitively to aluminium solubility in acid soils

Aluminium as a growth limiting factor has been recognized for many years. At high concentrations, aluminium (Al) ions reduce nutrient availability in soils, harm plant cells and thus inhibit plant growth. In addition, Al concentration may be a major factor filtering species composition on acid soils in favour of Al-resistant plants. In this study we analyse species responses and turnover along soil pH and Al gradients and we attempt to interpret the results with respect to the recognised aluminium solubility patterns. Plant community and soil data collected from mesophilous and acidophilous submontane broad-leaved forests of Western Slovakia were used for this purpose. Topsoil horizons were analysed for soil reaction (pH), organic carbon and extractable total aluminium. Species responses to the Al measurements were analysed and tested using CCA and the Huisman-Olff-Fresco (HOF) model. We calculated species turnover by accumulating the first derivatives of all HOF response curves, and interpreted them with respect to the Al solubility pattern observed in the soil dataset. We also performed a bioindication experiment to test how a species assemblage indicates the aluminium gradient. In total, 81% of species shows a significant response to the soil Al gradient. We identified that a rapid retreat of many species and, in consequence, high compositional turnover (ecotone) corresponded with a discontinuity in Al solubility observed at 130 mg Al kg−1 (pH 3.8). Here, the exchangeable Al became increasingly under-saturated with respect to the equilibrium attained at higher pH. This discontinuity was also visible in the bioindication experiment, where the prediction algorithm operated better at the acidic end of the gradient. The results indicate that the studied plant assemblages respond sensitively to soil Al solubility. Changes in aluminium solubility in soils correspond with ecotone between adjacent types of vegetation