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We report the results of investigating a low-voltage, polarization-insensitive, reflective-type modulator based on an epsilon-GaSe crystal and operated at the 1.960-eV line of a He-Ne laser. We demonstrate that the modulation in an Al-epsilon-GaSe-Cu device results mainly from the Franz-Keldysh effect. Relatively high speed and low operating voltage could make these modulators with Schottky-barrier contacts attractive devices in the red range of the spectrum.

Phosphoglycolate phosphatase (PGPase), a key enzyme of photorespiration in photosynthetic organisms, was purified from Chlamydomonas reinhardtii. The enzyme was an approximately 65-kDa homodimer with a pI value of 5.1 composed of approximately 32-kDa subunits not connected by any S-S bridges. It was also highly specific for phosphoglycolate with a K(m) value of 140 microm and an optimal pH between 8 and 9. The activity was strongly inhibited by CaCl(2), and it recovered competitively following the addition of MgCl(2) or EGTA. A mobility shift was observed in SDS-polyacrylamide gel electrophoresis by the addition of CaCl(2), indicating that the enzyme binds to Ca(2+). The N-terminal region of amino acid sequence deduced from cDNA sequence that was not contained in the purified PGPase had similar characteristics to those of typical stroma-targeting transit peptides in C. reinhardtii. The following region of the deduced sequence containing 302 amino acid residues was similar to p-nitrophenylphosphatase-like proteins, although the purified PGPase did not hydrolyze p-nitrophenylphosphate. Genomic DNA fragments from wild type containing the sequence homologous to the cDNA for PGPase complemented the PGPase-deficient mutant pgp1. Possible regulatory mechanisms during adaptation to limiting CO(2) were discussed based on the characteristics of the purified PGPase and the deduced amino acid sequence.

The literature data on the changes in composition, structure and properties of hemoglobin under the influence of ionizing radiation in vivo are reviewed. The algorithm of calculation of damaged hemoglobin molecule percentage is proposed. Four main realizations of radiation-chemical damage are considered. By the algorithm the estimation of the damaged molecules percentage resulted from the exposure of 10 Gy is given. Hemoglobin radiation damage is considered as one of the most important mechanisms triggering radiation sickness.

The binding of propranolol with plasma proteins and erythrocytes after oral administration of 80 mg of anapriline was studied in 12 patients with hypertensive disease. The content of propranolol fraction bound to plasma proteins was on the average 0.84 +/- 0.4. It was shown that propranolol to a considerable degree is captured by erythrocytes. The ratios of the erythrocyte content of propranolol free form to the plasma content were on the average 3.72 +/- 0.92 and 2.70 +/- 1.20, respectively, 2 and 4 hours after anapriline intake. During the assessment of the pharmacological parameters it is recommended to determine the contents of the total and free forms of propranolol in the whole blood rather than in plasma.

Thirty-two patients with hypertensive disease were treated with a cardioselective blocker of beta-adrenergic receptors acebutolol ("Sectral-400", Rhone Poulenc, France). The binding of the drug and its metabolites diacetolol to plasma proteins and erythrocytes and their excretion with the saliva were studied. The significant binding of acebutolol and diacetolol to erythrocytes was shown. The ratio of the content of the free form of these substances in erythrocytes to plasma content was on the average 1.54 +/- 0.96 for diacetolol and 1.93 +/- 1.01 for acebutolol. A good correlation of acebutolol and diacetolol contents in the saliva with their contents in plasma was found. The mean values of the protein-bound fraction were for acebutolol 0.133 +/- 0.038 and for diacetolol 0.106 +/- 0.050.

Gypsum models were constructed to study the transversal pharynx width and palate defect in 57 children with congenital opened palate clefts. Age-dependent increase in the defect width was noted and attributed to muscular dystrophy in the soft palate and lateral walls of the pharynx as a result of their dysfunction and hypodynamia.