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I present a study of laser-induced plasmas (LIPs) produced on the surfaces of molecular targets to create optimal conditions for high-order harmonics generation during the propagation of femtosecond pulses through the LIP. The resonance enhancement of a harmonic, two-color pump of plasma, quasi-phase-matching and nanoparticle-induced growth of the harmonic yield are analyzed, which allows for the formation of sources of coherent extreme ultraviolet radiation based on molecular plasma formation.

Our research has shown that the degree of photosensitivity of the cysteine proteases can be arranged in the following order: bromelain → ficin → papain. After the UV irradiation with 151 J·m -2 intensity of a bromelain solution, the enzyme activity has increased. No decrease in the catalytic capacity and the change in the size of the molecule was recorded in the 151-6040 J·m -2 range of irradiation intensities. A decrease in the catalytic capacity of ficin and the increase of its globule size occurred after exposure to a radiation of 3020 J·m -2 intensity. The decrease in papain activity was observed at the UV irradiation intensity of 453 J·m -2 , and an increase of the papain globule size was detected at 755 J·m -2 . Immobilization on chitosan matrix leads to the increase in the stability of heterogeneous biocatalysts with respect to UV irradiation in comparison with free enzymes. The changes in IR spectra of immobilized cysteine proteases practically do not affect the bands due to the protein component of the system: amide I, amide II, amide III. Therefore, it can be postulated that the chitosan matrix acts as photoprotector for immobilized ficin, bromelain and papain. The obtained results can be helpful for development of drugs based on chitosan and cysteine proteases in combination with phototherapy, as well as for choosing their sterilization conditions., (Copyright © 2019 Elsevier B.V. All rights reserved.)

We studied the effect of UV light (240-390 nm) in doses of 75.5-4530 J/m(2) on functional properties and level of intracellular messengers (cAMP, Ca(2+), NO) in lymphocytic cells of the peripheral blood. Correcting effects of UV light in a dose of 151 J/m(2) on cytotoxic activity of lymphocytes against Ehrlich ascetic carcinoma and calcium concentration in lymphocyte cytosol were observed. We found that UV light reduces the cAMP content and increases NO concentration (151-4530 J/m(2)) in photomodified cells. The involvement of adenylate cyclase and phosphoinositide signaling pathway into the mechanisms of modulation of functional properties of lymphocytes after exposure to UV light was demonstrated.

Activation of NADPH-oxidase enzymatic complex was observed after UV irradiation of the blood and neutrophil suspension in a dose of 151 J/m(2). UV irradiation in doses of 75.5 and 151.0 J/m(2) corrected myeloperoxidase activity and intensity of LPO processes in donor blood.

The UV-light influence (240-390 nm) in the doses range of 75.5 divided by 2265 J/m2 has been studied on structurally functional state of lymphocytes by the method of determination of the TBA-active products, spectrophotometric method and enzyme-linked immunosorbent assay. It has been shown that UV-irradiation dose increase led to the intensification of lipids peroxide photooxidation processes on lymphocytes, accompanied by the increase of their natural peroxidase activity and ability to sorb exogenic peroxidase. The association of peroxidase with the native and UV-irradiated lymphocytes results in the decrease of its catalytic activity.

It has been all round investigation of UV-irradiation influence in a wide dose range on the structural and functional properties of human blood lactate dehydrogenase (LDH) isoenzymes. The photoprotective action of biogenous amines on the functional activity of different enzyme isoforms was found. It has been established that the protective action of biogenous amines is caused by the formation of complex LDH--biogenous amine and by the acception of the active oxygen forms by the molecules of lactate dehydrogenase. Under the conditions of exogenous singlet oxygen generation in the presence of methylene blue, the inactivation of immobilized LDH tetramers and subunits was observed, that shows participation of this active intermediate in the processes of UV-modification of the enzyme in soluble and immobilized states. The scheme of processes of LDH molecules phototransformations in the presence of biogenous amines has been suggested.

The effect of UV radiation on the spectral characteristics of human nitrosohemoglobin in a wide dose range (151-4530 J/m2) was studied. It was shown that the irradiation of hemoprotein solutions with low doses of UV light (151-453 J/m2) led to local conformational rearrangements of the iron porphyrin moiety of the molecule. The apoprotein exhibited a high photostability under the conditions of the experiment. High doses of UV radiation (1359-4530 J/m2) induced the accumulation of methemoglobin in the protein sample. A scheme of the photoinduced formation of methemoglobin was elaborated.

The influence of ultraviolet (UV) radiation on structural and functional condition of membranes T- and B-lymphocytes of human blood is investigated. It is shown, that intergral flow of UV-light (240-390 nm) in doses 151-1359 J/m2 leads to the increase of the expression of some HLA-antigen (DR1, DR2, DR5, DR7) and Fc-receptors on membranes of B-lymphocytes. The level of HLA-antigen was increased by 20-500% from the initial state after exposure to different doses. The growth of the expression of Fc-receprots was registered in 80% of the donors in the range from 20 up to 540%. The minimum dose of UV-light (151 J/m2) caused the maximum effect. The reduction of the level of Fc-receptors by 10-90% relatively to the native condition was registered for T-cells in 80% of the donors. Groups of the donors were revealed, T-lymphocytes of which differed by the sensitivity to UV-radiation. The effect of "strengthening--weakening", resulting to the reduction of the initially high parameters and to increase in the initially low ones was found.

Photoinduced changes of human ceruloplasmin (hCp) under laser and ultraviolet (UV) radiation have been studied. A complex character of hCp spectral modifications points to a different degree of the protein molecule folding. After the influence of UV radiation (240-390 nm) in a dose range 906-4530 J/m2 the decrease of oxidase hCp activity was registered. These changes are thought to be connected with modification of the conformation of hCp active centre or copper reduction that was confirmed by the decrease of optical density at 610 nm. An inactivation constant (kf = 3.8 x 10(-4) 1/s) and a photoinactivation quantum yield (1.4 x 10(-4)) were calculated. Kinetic dependencies of o-phenilen-diamine oxidation by intact and UV-modified glycoprotein do not correspond to Michaelis-Menten equation. UV radiation in a dose range 151-4530 J/m2 induced increasing of ceruloplasmin superoxiddismutase activity. The influence of He-Ne laser radiation (1.3 mW; lambda = 632.8 nm, exposure time from 1 up to 30 min) leads to the raise of the hCp functional activity; superoxiddismutase activity changes more significantly. Possible photophysical and photochemical processes in hCp molecule, leading to photomodification and changes of protein functional activity have been represented on the scheme.

The investigation results on the UV-induced changes of lactate dehydrogenase structural and functional properties in the presence of some chemical substances, which are able to interact with the oxygen active forms have been summarized. As well the kinetic characteristics of the photoinactivation processes for heart and muscle LDH types in free state and in the complex with the exogenous agents have been studied. Singlet molecular oxygen has been shown to play an important role in the process of UV-modification of different protein isoforms. The scheme of probable physical and chemical processes, leading to the inactivation of lactate dehydrogenase molecules, has been suggested.

The contribution of hem and globin components of electrophoretic fractions of UV-irradiated human carboxyhemoglobin to photodestruction of the protein was studied. The changes observed are the result of summation of some processes unequal in intensity and direction that take place in microheterogeneous media of photomodified protein. Photosensitivity of hemoproteid in electrophoretic fraction depends on apoprotein condition, whereas the hem photoresistance cannot be the evidence of the photostability of the whole molecule.

The structural transformations of C1q-protein induced by the UV-light at doses 151 and 2265 J/m2 has been determined by means of acid-basic titration, IR- ans UV-spectrophotometry. These transformations are stipulated by unfolding of its molecules without change of the secondary structure types ratio and accompanies by exposition on aromatic amino acid residues as well as glutamine and asparagine acids, lysine, hydroxylysine and cysteine on the globule surface. The correlation between structural photomodifications and processes of functional activation of C1q has been established.