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The possibilities of using the energy dispersion synchrotron radiation X-ray fluorescence analysis (SRXFA) for control of blood plasma and liver trace element (TE) content in rats with hyperproduction of oxygen radicals and hair TE content in women with mammary hyperplasia and cancer are demonstrated. Our data show that activity of antioxidant enzymes superoxide dismutase (SOD) and catalase in the blood and liver depends on the amount of TE incorporated into the structure of the active center of these enzymes, which are responsible for antioxidant protection. A decrease of activity of these enzymes is accompanied by an increase of production of free OH radicals in the tissues. Clinical data demonstrated that scalp hair of patients with oncological mammary pathology was characterized by a significant decrease of concentrations of selenium (Se) and zinc (Zn) and by an increase of chromium (Cr). The Se deficit was more pronounced in patients with cancer than in those with mammary hyperplasia ( p The SRXFA method permits one to carry out a controllable correction of TE imbalance in many diseases whose development is caused by oxygen radical injury.

We have acquired the experience in the use of the linear electron accelerators type ILU in two main technological directions. The first one is the radiation-induced immobilization of various biologically active substances on polymer matrix. The second one is the radiation-induced linkage of low molecular polyethilenoxides in water solutions at the stage of formation of gels which are used as the basic component in the production of creams, gel-like toothpastes, contact media for ultrasonic diagnostics, absorption pastes. The report describes the production of cellulase complex stabilized on polymer carrier. The immobilization improved the quality of preparation: the pH range is widened with simultaneous increase of activity in more wide working temperature range (up to 70 centigrades). As a result the possibilities of their application for hydrolytic decomposition of cellulose containing materials are increased.

Possibilities of multielemental highly sensitive techniques of analysis have been studied: synchrotron radiation X-ray fluorescence analysis (SR XFA), and atomic emission spectrometry with inductively bound plasma (ISP) and atomic absorption spectrometry (AAS) with flame (air–acetylene) atomization for assay of element composition of bone tissue with minimal preparation procedure. Results of comparative studies of elemental composition of bone tissue samples from experimental animals with inherited accelerated aging (rats of OXYS strain) using the SR XFA, ISP and AAS techniques are presented. It is shown that there exists in principle a possibility of assay of 22 biologically important essential macro- and trace elements within the range of 1.0–100,000 μg/g with a mean square analysis error of no more them 10–15% when using SR XFA.

Two attenuated total reflection (ATR) spectrometers for study of substances highly-absorbing in the terahertz range have been developed. First system is a home-made single-reflection silicon ATR sampling module with an isolated sample cell to VECTOR-30 and IFS 66v/S Bruker spectrometers. This module was used for the examination of biological objects, including human blood, grounded rat bone, and other tissues. Second system is an imaging terahertz spectrometer using a tunable 100-W terahertz free electron laser as a source and a 160times120 microbolometer focal plane array camera (repetition rate up to 90 frames/s) as a recorder.

Progress in the construction of the second stage of Novosibirsk free electron laser and main results obtained during the year at the terahertz user stations are described.

Osteoporosis is a major cause of morbidity of older people. Direct financial expenditure for the treatment of osteoporotic fracture in the U.S. is estimated at $10-$15 billion per year. Though there are a number of methods for diagnostics of osteoporosis, X-ray radioscopy, NMR, element analysis, densitometry, etc., the development of new methods, which are complementary to the existing ones, is highly desirable. We have carried out first experiments on the examination of spectroscopic characteristics of healthy and osteoporosis-affected bone tissues in the terahertz spectral range. The samples were prepared by pressing of grounded bone tissue obtained from the intact rats Wistar and from the senescence-accelerated rats OXYS. The OXYS rats suffered hereditary osteoporosis developed early in life are, therefore, a useful model for examining osteoporosis. The first experiments using a Fourier-spectrometer showed considerable difference in the bone tissue absorbance for two strains, though statistic tests are still required. Because the bone tissue is a highly-absorbing substance, the attenuated total reflection spectroscopy seems to be the most adequate method for detailed bone study. Imaging radioscopy of bone samples using a matrix of microbolometers as a sensor and the Novosibirsk free electron laser as a source of monochromatic terahertz radiation is described.