Effect of low-intensity He-Ne laser irradiation on rat mesenteric microcirculation

Changes in microcirculation during low-intensity He-Ne laser irradiation were studied by measurement of blood vessels and lymphangions' diameter in anesthetized rat mesentery using method of videomicroscopy in vivo. We demonstrated that the red coherent light induced a significant increase in contractility of vessels' smooth muscle cells. The flow decreased in the mesenteric microvessels during H2O2-mediated oxidant stress was restored after He-Ne laser irradiation.     

Effect of fungal infection on the composition of acyl lipids in wheat seedlings

Infection of etiolated wheat seedlings with a root rot fungus Bipolaris sorokiniana caused a strong deviation in the fatty acid composition of their total lipids from the control. The deviation occurred at the expense of that lipid group, which predominates in a given plant organ (shoots or roots), and peak deviation coincided with the onset of a severe inhibition of growth.     

Effects of low-intensity laser irradiation on the state of blood proteins

The action of a low-intensity 632.8 nm-wavelength laser radiation on blood elements was studied. The degree of binding the fluorescence probes 1.8 ANS by blood proteins and cells was taken to be the index of the response to irradiation. The change of fluorescence of the oppositely charged probes indicates that a He-Ne laser radiation causes processes leading to a change of charge in proteins of a blood plasma with the negative charge decreased in most cases. The effect depends on individual characteristics of a biological object, on the exposure dose and the incubation time following the irradiation.     

Influence low-intensity laser irradiation on the ultrastructural organization of loach embryo cells

The ultrastructural organization of loach embryo cells (Misgurnus fossilis L.) at the stage of the first and the tenth embryo divisions was investigated under the influence of low intensity helium-neon laser irradiation of 5 min exposure. It was determined that the effect of laser irradiation led to ultrastructural changes: the shape of mitochondria and multivesicular bodies changes. The obtained results explain the possible mechanism of influence of low-intensity laser irradiation at the cellular level.     

Effect of photosensitizers pheophorbide a and protoporphyrin IX on skin wound healing upon low-intensity laser irradiation

The effect of photosensitizer with subsequent He-Ne (632.8 nm; 3 mW/cm²) laser irradiation on experimental skin wound healing has been studied. Pheophorbide a and protoporphyrin IX were used as photosensitizers. It was found that application of the photosensitizer and subsequent laser irradiation, first, decreased the amount and the functional activity of leukocytes in the wound exudate and, second, inhibited the SOD activity as compared with that of the control group. Moreover, pheophorbide and protoporphyrin practically did not affect the total healing period but decreased the length of the inflammation stage. It was supposed that these effects are related to generation of reactive oxygen species during irradiation.     

Protective effect of low-intensity laser irradiation under acute toxic stress

We studied how short-term preexposure of the thymus zone in male outbred NMRI mice to helium-neon laser light (632.8 nm, 0.2 mW/cm²) affects the activity of cells of the immune system under acute toxic stress. The stress was modeled by introducing a bacterial lipopolysaccharide that significantly enhanced the production of a number of cytokines in macrophages: interleukins 1α, 1β, 6, and 10, and tumor necrosis factor TNF-α. Single exposure of healthy mice to laser light did not cause any significant change in the production of cytokines and nitric oxide in cells but increased the production of the heat shock proteins HSP25, HSP70, and HSP90. Nonetheless, if mice were exposed to red light before inducing toxic stress, then the production of almost all the cytokines studied and nitric oxide was noticeably normalized. Moreover, the production of the heat shock proteins studied was also normalized. Thus, preexposure of a small region of the animal skin surface to laser light markedly decreased the toxic effect of lipopolysaccharide.     

The three-dimensional structure of presynaptic mitochondria in a factorial experiment involving irradiation of the brain with a low-intensity laser

Parameters of the mitochondrial ultrastructure in the presynaptic terminals of the dorsal horn have been investigated in the control cats and in those exposed to helium-neon laser. Using the factor analysis and stereologic approach changes have been revealed in actual tridimensional parameters of organelles.     

Effect of continuous low-intensity microwave irradiation on the behavior of albino rats

A study was made of a single 10 min exposure of albino rats to microwaves (6 GHz, 0.2 MW/cm2) on their orientative-trying reaction. The locomotive activity, attentiveness and trying activity of the experimental animals were found to increase.     

Effect of laser microbeam irradiation of the nucleus on the cleavage of mouse eggs in culture

Two-cell mouse eggs were irradiated by a helium-cadmium laser on a spot of about 4 micron2 (d = 2.2 micron) in one or both nuclei either continuously or repeatedly at 0.36 erg micron-2 sec-1 and then cultured to observe cellular development. After exposing one nucleus to the microbeam to five or seven 1-sec pulses (1.80 or 2.52 ergs micron-2, respectively), about 45% developed to the 3-cell stage in 24 hr of culture. In overnight cultures of the 2-cell eggs in which both nuclei were irradiated for 9 or 20 sec continuously, 40 (9 sec) and 50% (20 sec) of the eggs remained at the 2-cell stage, while 45 (9 sec) and 25% (20 sec) developed to the 4-cell stage. Irradiating only one nucleus in a 2-cell egg by seven pulses in a spot of 4 micron2 amounting to 10 ergs reduced cleavage 45%. When both nuclei were each irradiated by a 9-sec continuous laser beam (totaling 13 ergs), about 40% of the embryos of the 2-cell stage did not divide. The effect of seven pulses on the blastomere cleavage of 2-cell mouse eggs appeared to be comparable to that of continuous 9-sec laser irradiation. Both pulse and continuous laser microirradiation methods may be developed for inactivation of the nucleus as a nonpipetting , less injurious method for enucleation of mammalian eggs.     

Modification of the damaging effect of alpha-particles on Escherichia coli K-12 by low-intensity laser irradiation

A study was made of the combined effect of laser (helium-neon laser, lambda = 633 nm) and alpha-radiation on survival of Escherichia coli K-12 cells of different genotypes. Pre- and post-irradiation exposures to laser-radiation diminished the damaging effect of alpha-particles. In the latter case, modification of survival was more pronounced.     

Effect of one-time and chronic low-intensity irradiation on cathepsin L activity in rat brain

The effect of the total single and chronic roentgen irradiation in the dose of 0.25 Gy on the rats to alteration dynamics in lysosomal cysteine cathepsin L [CE 3.4.22.15] level in different brain regions (cortex, cerebellum, middle brain, varolian, hippocampus, striatum) was studied as a result of 1, 12, 24, 120 and 168 hours of exposure. The data obtained displayed the opposite consequences of chronic effect of 0.01 Gy during 25 days if compare with the single irradiation by 0.25 Gy that led to the cathepsin L changes different in directivity and activity level in dependence on brain region and post-irradiation period.     

Effect of low-intensity laser radiation on the brain cholinesterase activity of rats

In studying the activity of cholinesterase in subcellular fractions of rat brain affected by laser radiation of low intensity (9 mW) symbasic changes were noted which were more pronounced in vitro than in vivo.     

Effect of stearoylethanolamine on composition of various classes of lipids in rat heart tissue under ischemia-reperfusion

The effect N-stearoilethanolamines on lipide classes and their fatty acid composition was studied in the isolated rat heart under ischemia--reperfusion. It was shown that the amount of cholesterol esters increased at ischemia--reperfusion by 4.6 fold. The addition of 10(-7) M, 10(-6) M and 10(-5) M of N-stearoilethanolamines into perfused solution prevented these negative consequences of the myocardium ischemic injury. The addition of N-stearoilethanolamines decreased the quantity oleinic (18:1 omega 9) and free n-6 fatty acids. N-stearoilethanolamine lowered the amount of short chain saturated fatty acids and also polyunsaturated n-6 fatty acids in cholesterol esters. As well the lipide composition of perfused solutions was also investigated.     

Effect of six species of white-rot basidiomycetes on the chemical composition and rumen degradability of wheat straw

This study was conducted to investigate changes in in vitro dry matter digestibility (IVDMD), volatile fatty acids (VFA) production and cell-wall constituent degradation in wheat straw treated with six white-rot fungi: Daedalea quercina, Hericium clathroides, Phelinus laevigatus, Inonotus andersonii, Inonotus obliquus, and Inonotus dryophilus. The incubation of wheat straw for 30 days at 28 C improved IVDMD from 41.4 (control) to 59.2% for D. quercina, 56.3% for H. clathroides, 50.2% for P. laevigatus, 51.4% for I. andersonii, 52% for I. obliquus, and 55.9% for I. dryophilus. In contrast, the growth of fungi was accompanied by the dry matter loss of wheat straw: 43% for D. quercina, 12% for H. clathroides, and 22-25% for the other fungi. It is evident that the increase in digestibility by D. quercina was not offset by a loss of dry matter. The total VFA production during the rumen fermentation of fungus-treated straw was slightly increased by H. clathroides and I. dryophilus only. Neutral detergent fiber (NDF) and acid detergent fiber (ADF) were reduced in fungus-treated straw. Out of the three fractions (hemicellulose, cellulose, and lignin), hemicellulose and lignin showed the largest proportionate loss after inoculation with the fungi D. quercina, H. clathroides, P. laevigatus, and I. obliquus. The other two fungi showed the largest proportionate loss in cellulose and hemicellulose contents. The results of this study suggest that the digestion enhancement of wheat straw colonized by white-rot fungi is regulated by complex factors including the degradation of structural carbohydrates and lignin.