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Biomedical subjects

R V Ambartsumian

Publications and source records attributed to R V Ambartsumian.

5 recordsLinked to original sources
PubMed2003

Activation of molecular oxygen by infrared laser radiation in pigment-free aerobic systems.

With the goal of mimicking the mechanisms of the biological effects of low energy laser irradiation, we have shown that infrared low intensity laser radiation causes oxygenation of the chemical traps of singlet oxygen dissolved in organic media and water saturated by air at normal atmospheric pressure. The photooxygenation rate was directly proportional to the oxygen concentration and strongly inhibited by the singlet oxygen quenchers. The maximum of the photooxygenation action spectrum coincided with the maximum of the oxygen absorption band at 1270 nm. The data provide unambiguous evidence that photooxygenation is determined by the reactive singlet (1)Delta(g )state formed as a result of direct laser excitation of molecular oxygen. Hence, activation of oxygen caused by its direct photoexcitation may occur in natural systems.

Aerobiosis↗
PubMed1991

[The content of biologically active substances in the margin of a stomach ulcer being treated with a copper-vapor laser].

A study was made of the effect of laser therapy on the content of she biologically active substances serotonin, histamine, PGE2 and PGF2 alpha as well as on the adenylate cyclase system--adenylate cyclase activity and cGMP content. Direct exposure to laser produced an appreciable increase of the content of serotonin and histamine, PGE2 and PGF2 alpha, cAMP and of adenylate cyclase activity. On the healing of ulcerous defect after 5-6 sessions of laser therapy a decrease of the content of serotonin, a rise of histamine, PGE2, PGF2 alpha, cAMP accumulation and adenylate cyclase activation were recorded.

Adult↗
PubMed1991

[Effect of laser irradiation of different intensities on the processes of healing of stomach ulcers].

Patients with stubborn peptic ulcers were exposed to copper vapor laser of various intensities with similar irradiation energy. The best therapeutic effect (more rapid ulcer healing) was achieved when ulcer bottom and edges were exposed to laser of higher intensity; the effect is explained by a higher stimulation of inflammation and a more rapid and clear-cut restructuring of connective-tissue stroma on ulcer bottom.

Adolescent↗