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Changes of selenium, chromium, antimony, silver, cobalt, rubidium, zinc, iron and bromine concentration in whole blood of Wistar rats were examined in early period after gamma irradiation by 3, 7.5 and 10 Gy. Level of these trace elements was measured by instrumental neutron activation and X-ray fluorescence analysis. Diagnostic and prognostic significance of some trace elements were established.

The authors have for the first time developed a device and created an experimental model of osteotomy in 13 adult mongrel dogs for comprehensive (radionuclide, x-ray, histologic, neutron-activation methods) investigations of the time course of reparative regeneration of maxillary laminar osseous tissue in conditions of perforating osteotomy, followed by dosed distraction (0.75 mm in 48 h by the device activation twice a day). The tension and stretching factors were found conducive to bone formation in the laminar osseous tissue. Based on these data, new osteotomy methods may be developed and the existent ones improved, as well as the methods for the treatment of patients with facial bone defects and deformations, based on the distraction methods of treatment.

A technique of in vivo neutron activation analysis (NAA) of calcium levels in lumbar, thoracic and cervical segments of the spinal column separately and as a whole has been developed. Special device provides selective irradiation by neutrons of a vertebral segment under study while a highly-sensitive spectrometric unit registers radionuclides induced in bone tissue during radiation exposure. For radiation exposure 5 or 10 238Pu-Be neutron sources with 5.10(7) neutrons s-1 output of each source are used. The spectrometric unit consists of 4 scintillation detectors with NaI (Tl) crystals of 150 mm in diameter and 100 mm- thickness arranged in a line tightly one after another. The time of exposure depends on the number and mutual arrangement of the neutron sources and is selected given the dose equivalent at depth of positioning of the spinal cord does not exceed 1 cZv (REM), the quality factor for fast neutrons equals 10. The recording duration is 20 min, the intervals between radiation exposure and recording do not exceed 3 min. The magnitude of the total error of an individual measurement estimated by reproducibility of the data obtained in 2 series of in vivo NAA of the spinal calcium levels in 6 volunteers with the use of 5 neutron sources amounts to an average of 4.8%. When used 10 sources, this error can be reduced to 2.0-3.2%.

The levels of 21 chemical elements (N, Na, Mg, P, Cl, K, Ca, Sc, Cr, Mn, Fe, Co, Cu, Zn, Se, Br, Rb, Sr, Ag, Sb, Hg) were measured in 52 normal subjects aged 18 to 35 years with the use of a complex of instrumental methods including the neutron activation and x-ray fluorescence analysis. Effects of day time, season, sex and age on salivary composition were examined. The measured concentrations of chemicals in mixed nonstimulated saliva were different in each individual; some of them were liable to change only in the course of 24 hrs, therefore the time for saliva collection had to be strictly defined: 10-12 a.m. were found the optimal hours for saliva collection. Neither sex, nor age, nor season influenced the concentrations of the examined 21 chemicals, except Hg whose concentration grows with age.

Male rats of the Wistar strain were for 40 days exposed to hypokinesia and hypodynamia. After exposure bone biochemical, physical, chemical, morphological and strength parameters were investigated. Both simulation studies led to changes in calcium and phosphorus metabolism but the nature of bone changes was different. It is concluded that the efficacy of drugs used as countermeasures in animal simulation experiments should be assessed by both exposures, viz. small size cages and suspension, because they reproduce different mechanisms of potential bone lesions in microgravity. It is also inferred that various countermeasures should be used in combination to yield the best results.

The major mineral components and electrolytes (K, P, Mg, Na, Cl, Mn, Fe, Co, Zn, Br, Sr) of the maxillary lamellar bone tissue and of the reparative regenerate were examined over the course of healing of maxillary nasofrontal artificial defects of various sizes (5 X 20, 7 X 20, 10 X 20 mm) perforating the nasal cavity. Check-ups carried out in 3, 4, and 8 mos after surgery have shown no osteal joining of the maxillary defect. The level of ossification by the 8th month of the follow-up, as evidenced by the content of the major osteotropic elements, just a little surpasses 50-70% of the normal value.

As it has been demonstrated by a morphological investigation of the prostate from 85 corpses of various ages, each age period defined has certain specific objective morphometric indices, histological peculiar features of epithelium and changes in zinc content. The prostatic epithelium is the most monomorphous and the least active in the prepubertal group. In persons 14-40 years of age, the epithelium is characterized by morpho-functional features of high activity with preservation of its histological peculiarities. This corresponds to zinc content within the limits 48.10+/-9.10-64.10+/- +/-6.10 mg/kg in dry tissue of the gland. The most outstanding feature of the prostatic epithelium during transitional period of age is polymorphism of its structure, which corresponds to the greatest zinc content (115.10 +/- 13.10 mg/kg). In elderly and old persons this index is somewhat decreasing.

Due to activation analysis involving the use of neutrons from a nuclear reactor, the concentrations of 11 trace elements: scandium, iron, cobalt, mercury, rubidium, selenium, silver, antimony, chrome, zinc and terbium in intact bone and skeletal tumors were measured. 76 specimens of bioptates and resected material of operations for bone tumors and 10 specimens of normal bone tissue obtained in autopsies of cases of sudden death were examined. The concentrations of trace elements and their dispersion patterns in tumor tissue were found to be significantly higher than those in normal bone tissue. Also, the concentrations of some trace elements in tumor differed significantly from those in normal tissue; moreover, they were found to depend on the type and histogenesis of the neoplasm.

A method of instrumental photonuclear activational analysis is developed for estimation of nitrogen, fluorine and phosphorus in bone tissue samples. The irradiation with maximal energy 15.6 MeV, obtained on linear accelerator of electrons LUE-25 RIMR AMN USSR, was used for activation. Estimations were carried out by the relative method with recording the intensity of positron radiation of 13N, 18F and 30P in samples and standards by means of device for gamma-gamma-coincidence. In chosen regimens of the analysis the statistical errors of nitrogen and phosphorus estimation did not esceed 1.5%, of fluorine-5%; the sensitivity of the method for nitrogen was found to be 0.06% for fluorine-0.006%, for phosphorus-0.12%; on analysis of recovery the relative standard deviation in results accounted for nitrogen-5.4%, for fluorine-6.7% for phosphorus 6.2%. Correctness in concentrations of the elements, estimated by the method described, correlated with the data, obtained in activation with reactor neutrons and with 14MeV generator neutrons.

A method of a combined use of fiber gastroscopy and x-ray fluorescent analysis was elaborated for a study of the chemical composition of the gastric mucosa. Fr, Cu, Zn, Br, and Rb concentrations were determined in gastric mucosa biopsy specimens obtained during fiber gastroscopy, using x-ray fluorescent analysis. The concentrations of trace elements in the gastric mucosa were determined in 13 healthy persons, in 23 patients with chronic mucosal atrophy, in 15--with gastric ulcer, and in 16--with polyps. Besides, the content of trace elements was determined in the tumorous tissue of 66 gastric cancer patients. The results of the investigation revealed a statistically significant rise of mean Fr concentrations on the ulcer edge, in polyps and tumorous tissue as compared to the unchanged mucosa. Polypous tissue differed from the normal gastric mucosa by a low level of Cu, the difference being statistically significant. A tendency to a decrease in Zn content as compared to the unchanged mucosa was noted in the edge of ulcerative defects. The method can be effectively used for intravital studies on Fr, Cu, Zn, Br, and Rb levels in the G. I. tract mucosa.

A study was made of the dynamics of structural, morphological and histological changes in the thyroid gland of Wistar rats subjected to gamma-irradiation (7.5 Gy) and thermal burn (15% of a body surface) and a combined effect of these two factors. Concurrently, an estimation was made of the iodine content of the gland, using the roentgen-fluorescent method, and of the thyroxin concentration in blood. The results obtained were considered in relation to the clinical course and the outcome of the affection caused by the combined and individual effects of radiation and heat. It is conluded that the cell-tissue substrate providing the thyroid hormones synthesis does not undergo substantial variations from normal values which could be considered as a cause of the decrease in the hormone content of blood after burn, irradiation and the combined radiation and thermal injury. Other possible causes of hyperthyroxynemia are discussed.

Neutron-activation method was employed to determine the concentration of magnium, sodium, chlorine, phosphorus and calcium in different bone tumors. In relation to normal skeletal tissue in tumor tissues higher concentrations of chlorine and sodium but lower concentrations of calcium and phosphorus were found. The greatest changes in the macromolecular content were noted in sarcoma tissues. Bone tumors differ reliably one from the other by concentrations or ratios of macroelements concentrations, this fact may be used for the differential diagnosis.

The stable intrathyroid iodine concentrations characteristic of nodular goiter, thyroid adenoma and cancer were determined by means of neutron activation analysis of resected material, Mean iodine levels in the destruction focus in cancer, adenoma and nodular goiter were 32 +/- 5, 174 +/- 38 and 344 +/- 43, respectively. while 960 +/- 91, 527+/-138 and 639+/-66 micrograms of iodine per 1g of wet weight were found in the surrounding apparently intact tissues of thyroid parenchyma. The importance of the difference between the absolute value of iodine concentration in the destruction focus and that in intact tissue for differential diagnosis of thyroid cancer is discussed.

In Wistar rats a study was made of a functional condition of the thyroid gland 1, 6 and 24 hours after partial pancreatectomy. The following signs-served as criteria of a functional condition of the gland: the amount of neutrone-activated iodine in iron, iodine-absorptive capacity of the gland by I131, the amount of protein-bound stable and radioactive iodine in the blood, a morphological condition of the gland structures. It was demonstrated that, despite the initial intensification of the process of synthesis and secretion in the thyroid gland, its secretory activity fell by the end of the experiment. This reduction is regarded as an adaptive response to partial insulin deficiency.