A study of the effect of low-intensity laser radiation of the blue, green, and red spectral regions on the healing of experimental skin wounds in rats

The effect of low-intensity laser radiation of the blue (441.2 nm), green (532 nm), and red (632.8 nm) spectral regions on the healing of experimental skin wounds in rats has been studied. The effect of the traditionally applied laser radiation in the red region has been compared with the effect of laser radiation in the other spectral regions, assuming that, upon irradiation of wounds by lasers emitting in the blue and green regions, a similar effect can be achieved at lower doses. The following parameters characterizing the healing of experimental wounds were used: the functional activity of phagocytes of wound exudates, which was determined by luminol-dependent chemiluminescence, and their number; the antioxidant activity of wound exudates; and the rate of healing, which was determined as a change in the wound area. It was shown that irradiation with laser accelerated the healing of wounds in all cases. The exposure to laser radiations in the red (1.5 J/cm), blue, and green (0.75 J/cm2) spectral regions shortened the time of wound healing from 22 to 17 and 19 days, respectively. The functional activity of leukocytes after the exposure increased on day 5 after the infliction of the wound, whereas in the control it decreased. The superoxide dismutase activity increased in all experimental groups by day 5 after the operation. A maximum increase in the superoxide dismutase activity occurred after the exposure to laser radiation in the red region at a dose of 1.5 J/cm and in the blue and green spectral regions at a dose of 0.75 J/cm2.     

Effect of copper vapor laser on the microrelief and ultrastructure of gastric mucosal glandulocytes

It was investigated the influence of low intensive irradiation by the copper++ vapor laser (lambda-510.6 nm) on the glandulocytes of gastric mucosa of 28 white rats. The doses of endogastric irradiation were 6.78, 20.34 and 33.90 J/cm2. It has been shown that after irradiation of gastric mucosa with the copper++ vapor laser the microrelief and ultrastructure of glandulocytes changes testified to stimulation of specific secret function. This changes took place under irradiation doses from 6.78 to 20.34 J/cm2. The doses exceeded 20.34 J/cm2 caused the alterations of the epitheliocytes. Thus it is necessary to take into account that during laser therapy of the ulcers with copper++ vapor laser, doses of 20.34 J/cm2 caused the alterative effect on the epitheliocytes.     

The influence of the parasite invasion on antioxidant enzyme activity in the liver and muscles of a host, the Black Sea flounder Psetta maxima maeotica

The influence of the intestine cestode Botriocephalus gregarius on the antioxidant enzyme system in the liver and muscle of its host, the Black Sea flounder Psetta maxima maeotica, was studied. The significant increase of superoxidedismutase activity in examined tissues and changes of catalase and peroxidase activities were detected. High correlation (r > or = 0.6) between enzyme activities and the parasite number was noted. The possibility to use antioxidant enzyme activity as biomarkers of the parasite invasion in fish is discussed.     

The effect of low-intensity laser irradiation in the blue, green, and red spectral ranges on healing of experimental skin wounds in rats

The effects of low-intensity laser irradiation in the red (632.8 nm), green (532 nm), and blue (441.2 nm) spectral ranges on wound healing has been studied in rats. The effect of the traditionally used red laser irradiation has been compared with the effect caused by laser irradiation in other spectral ranges, aiming to support the provisional hypothesis that a similar healing effect could be achieved at lower doses of wound irradiation by lasers emitting in the blue and green spectral ranges. The following parameters have been used to characterize healing of the experimental wounds: the functional activity of phagocytes in the wound exudate, which was determined from luminol-dependent chemiluminescence, the phagocyte number; the wound exudates’ antioxidant activity; and the rate of healing, which was determined as the change of the wound surface area. It was found that in all cases the laser irradiation accelerated the healing of wounds. Exposure to red laser irradiation at the dose of 1.5 J/cm²), and to blue or green laser irradiation at a dose of 0.75 J/cm² shortened the time of the wound healing from 22 to 17 and 19 days, respectively. The functional activity of leukocytes in irradiated groups increased by day 5 after surgery, whereas in the control group it decreased. The superoxide dismutase activity increased in all experimental groups by day 5 after surgery. Laser irradiation in the red spectral range at a dose of 1.5 J/cm² resulted in a larger increase in superoxide dismutase activity, as compared to that found after exposure to laser irradiation in the blue and green spectral ranges at a dose of 0.75 J/cm².     

低能量激光照射对小鼠脾脏NK细胞活性影响的试验研究

目的：研究能量激光照射对小鼠NK细胞活性的影响,以便从NK细胞活性的角度阐明其免疫调节效应。方法：以BALB／c小鼠为研究对象,应用7.337J/cm^2,11．00J/cm^2,14．67J/cm^2,22．00J/cm^2和36．67J/cm^2五种剂量的氦氖激光作小鼠内眼角照射,连续照射8d,并于照射开始后第3d,6d,9d,13d和第17d,动脉监测实验鼠脾脏NK细胞活性。结果：以日剂量为7.33J/cm^2,11.00J/cm^2,14.67J/cm^2和22.00J/cm^2LELI照射小鼠四个剂量组均可增强NL细胞的活性（P＜0．01或P＜0．05）,但其峰值的出现随着LELI剂量的增大而加快,22．00J/cm^2剂量组在第3d就达到峰值,而其余三组则分别在第9d或第13d时达到峰值,与相相反,大剂量36.6J/cm^2ELEI组NK活性则表现出明显的抑制效应。结论：适当剂量的低能量激光照射剂可对小鼠脾脏NK细胞活性产生增强效应,而过大剂是LELI则产生抑制效应。     

Modulating effect of helium-neon laser radiation on the state of antioxidant and hydroxylation systems of quail liver under X-ray irradiation and chemical intoxication

Red laser light (lambda = 633 nm) in a dose of 9.5 mJ/cm2 defends quail's embryo from X-ray irradiation (8.5 Gr). It is expressed in the 1.9 times decrease of embryo mortality on early term of incubation and 1.6 times increase of hatch in a group of embryos, which were affected by X-rays and laser radiation compared with an embryo, irradiated only by X-rays. Repeated laser irradiation of adult quails (dose 21 J) after CCl4-intoxication led to normalization of hydroxylation and antioxidant systems functions.     

Single cell analysis of PKC activation during proliferation and apoptosis induced by laser irradiation

Laser irradiation has been shown to trigger cellular proliferation and apoptosis in various cell types. Studying the signaling pathways involved in the laser irradiation is important for understanding these processes. In present study, to monitor the protein kinase Cs (PKCs) activity in living cells in real time, we transfected and screened human lung adenocarcinoma cells (ASTC-a-1) stably expressing C kinase activity reporter (CKAR) constructed based on fluorescence resonance energy transfer (FRET) technique. The CKAR is a specific, reversible reporter of phosphorylation by PKCs and it can monitor the ongoing balance between PKCs and phosphatases. The increasing dynamics of PKCs activity is monitored during cell proliferation induced by low-power laser irradiation (LPLI) (0.8 J/cm2) in serum-starved ASTC-a-1 cells stably expressing CKAR reporter using FRET imaging on laser scanning confocal microscope and using spectrofluorometric analysis on a luminescence spectrometer, respectively. However, the decreasing dynamics of PKCs activity has been monitored in real time using FRET imaging for the cells treated with high fluence LPLI (60 J/cm2), which was previously found to induce cell apoptosis. Taken together, LPLI induces the ASTC-a-1 cell proliferation by specifically activating PKCs. However, PKCs activity decreases during cell apoptosis induced by high fluence LPLI. Our results indicate that PKCs play an important role in the laser irradiation-induced biological effects.     

The response of Na+/K+ -ATPase of human erythrocytes to green laser light treatment

The objective of this study was to investigate the response of Na(+)/K(+)-ATPase of human erythrocytes to green laser irradiation. Effects of green laser light of fluences 9.5-63.3 J.cm(-2) and merocyanine 540-mediated laser light treatment were studied. Isolated erythrocyte membranes (protein concentration of 1 mg/ml) were irradiated by Nd:YAG laser (532 nm, 30 mW) and then incubated in a medium with 2 mM ATP for 30 min. Activity of ATPase was determined colorimetrically by measuring the colored reaction product of liberated inorganic phosphate and malachite green at 640 nm. Contribution of Na(+)/K(+)-ATPase to overall phosphate production was determined using ouabain. A positive effect of green laser light on Na(+)/K(+)-ATPase activity was observed. The dependence of enzymatically liberated inorganic phosphate on light fluence showed a linear correlation (R(2)=0.96, P=0.0005) for all fluences applied (9.5-63.3 J.cm(-2)). On the other hand, MC 540-mediated phototreatment caused a suppression of enzyme activity.     

The role of lipid peroxidation products in the effect of He-Ne laser on human blood leukocytes

The role of lipid peroxidation products formed in membranes of human blood leukocytes after irradiation with He-Ne laser was studied. It was found that low-intensity laser irradiation (0.3-1.6 J/cm2) leads to both cell activation and an increase in the content of lipid peroxidation products. The intensity of lipid peroxidation was analyzed by estimating the amount of TBA reactive products and lipid diene conjugates. Irradiation in the presence of an exogenous photosensitizer (protoporphyrin IX) enhanced the phenomena observed. The use of antioxidants (tocopherol and ionol) completely eliminated the laser-induced effects (changes in leukocyte activity and accumulation of lipid peroxidation products). These results can be explained by the fact that laser irradiation leads to the activation of lipid peroxidation in leukocyte membranes, which in turn enhances the response of cells to the stimulus (priming).     

DNA synthesis in monkey kidney cellular culture, hematoporphyrin sensitized and He--Ne laser irradiated.

He--Ne laser irradiation for 1-45 J/cm2 has four actions upon monkey kidney cell cultures: a) a stimulation of nuclear DNA synthesis after 20 J/cm2; b) a diminution of replication after higher dose (45 J/cm2); c) inhibition of nuclear DNA synthesis and d) a marked cytotoxic effect. At lower radiation fluences (1-5 J/cm2) the influence on the biosynthesis of DNA is not significant.     

The effect of low-intensity red and infrared laser radiation on the rat arterial and deoxygenated blood

In vitro experiments the effect of low-intensity red or near-infrared laser irradiation on the blood samples (1.5 ml from abdominal aorta of Wistar rats) were studied. The diode laser light (lambda = 650 nm or 808 nm, power density 15.6 mW/cm2, duration 15 min) were used. In some experiments the deoxygenated blood as object for comparison with arterial blood was chosen. Under red laser irradiation we observed a significant increase of average volume of erythrocytes as well as mean amount of free (disaggregated) leukocytes especially in case of the deoxygenated blood. At the same time the concentration of Ca2+ and Na+ were decreased. The effects of infrared laser irradiation on indices mentioned above were not significant. We believe that red low-intensity laser irradiation on the blood is an important factor for theological properties in the field of microcirculation.     

Antimicrobial activity of argon fluoride (ArF) excimer laser on gram-negative bacteria

The objective of this study was to evaluate the antibacterial activity of argon fluoride (ArF) excimer laser radiation on clinically important strains of gram-negative bacteria. The antibacterial activity of ArF excimer laser radiation was evaluated on two Acinetobacter baumannii, one Enterobacter cloacae, three Escherichia coli, two Helicobacter pylori, one Klebsiella pneumoniae and two Pseudomonas aeruginosa strains. The strains were isolated from clinical specimens and typed by the usual biochemical procedures. Square agar plates of 12 x 12 cm were divided into rectangular (2 x 3 cm) regions and spread with 0.5x 10(4) colony forming units (CFU)/ml of bacterial suspension. The excess liquid was removed and the plates were allowed to dry for 30 min. A total of 96 rectangular (2x3 cm) regions were used for each strain, in order to test an equal number of laser parameters. Each rectangular region was irradiated with different laser parameters, using a 193 nm ArF excimer laser, linked with a simple Galilean afocal system and a rectangular diaphragm of the same dimensions as the original laser beam cross-section, at a distance of 10 cm from the irradiated surface. This system was used in order to keep the laser pulse energy under 80 mJ and to cut-out the non-transverse electromagnetic mode branches of the laser beam. We then studied the bacterial survival ratio versus the number of laser pulses, the repetition frequency and the total laser beam fluence. Our results showed that the total laser beam fluence was the most important parameter to consider in evaluating the bactericidal effect of ArF excimer laser radiation. A critical value of the total fluence was determined for each strain, such that, for laser beam fluences greater than this critical value, no colonies appeared to survive while, for laser fluences less than this critical value, the survival ratio did not exceed 2 x 10(7) CFU (2 x 10(-5)%). These critical values were found to vary between 8 J/cm2 and 16 J/cm2 for the bacterial species studied. Under these conditions, ArF laser irradiation is promising for the sterilisation of hard surfaces and for in situ application.     

578.2 nm激光照射对兔视网膜的损伤效应研究

研究578.2 nm激光照射对兔视网膜的作用特点,以新西兰白兔5只10眼为实验对象,铜蒸汽激光(578.2 nm)通过裂隙灯照射兔视网膜后极部,照射时间为100 s,光斑直径为2 mm,照射剂量分别为60 J/cm2、80 J/cm2、100 J/cm2、120 J/cm2、160 J/cm2、200 J/cm2,每组4个光斑。照后1 h及24 h进行眼底照相及光镜观察。照光后可见,随激光功率密度的增加,兔视网膜的损伤也逐渐加重,并且照后24 h的损伤要重于照后1h。80 J/cm2和60 J/cm2在照后1 h和24 h均未发现明显改变。578.2 nm激光照射白兔后的主要病理学改变位于脉络膜。因此,以578.2 nm激光作为光动力治疗眼底疾病的光源时,照射剂量不宜超过80 J/cm2。     

Antioxidant status of ewe's blood during pregnancy and lactation

Antioxidant status of ewe's blood during pregnancy and lactation was studied. It is revealed that the lipid peroxidation in erythrocytes is decreased, whereas in blood plasma is increased in the middle pregnancy, reaching the maximum shortly before peak of progesterone production. The activities of antioxidant enzymes are increased at the end of pregnancy, when the level of progesterone in blood is maximal. The positive correlation between plasma progesterone level and activity of erythrocyte superoxide dismutase (p < 0.01), between plasma cortisol concentration and total antioxidant capacity of blood plasma (p < 0.05) are revealed. It is shown, that the activities of antioxidant enzymes reach a maximum in the critical periods of pregnancy, providing the protection of the maternal organism and the fetus against negative influence of free radicals. The positive correlation between a level of hormones and separate parameters of antioxidant system in blood allows to assume, that progesterone participates in the regulation of enzymatic part of the antioxidant system, while cortisol is implicated in the regulation of the non-enzymatic component of this system in ewes.     

B16 melanoma development in black mice exposed to low-level microwave radiation

The effect of low-level microwave exposure, 2,450 MHz, at a power density of 1 mW/cm2 and specific absorption rate of 1.2 mW/g, continuous waves (CW) or pulsed waves (PW), 2.5 h/day, 6 sessions/week until death (up to 690 h of irradiation), has been studied in black C57/6J mice with B16 melanoma. The results show that no significant effects are observed on tumor development or on survival times compared to controls, or between CW- and PW-treated animals.     

Effects of UV-irradiation of carp sperm and its modification by caffeine

In connection with the development of UV-induced mutagenesis in carp, the effects of UV-irradiation of sperms have been studied in the range of doses 0.3-40 J/m2. The irradiation did not cause reduced fertilization ability and cleavage delay. Small doses of irradiation (0.6 J/m2) produced stimulating effect on embryo survival, the larvae yield decreasing and the amount of aberrant anaphases increasing, as the doses are increased. LD50 is 6.0 J/m2 for embryonal period of carp development, photoreactivation increases it up to 23.5 J/m2. Correlation between embryo viability and their resistance to UV has been found (r = +0.68 +/- 0.20). Modification of the effect of sperms irradiation with caffeine has been also studied. Strengthening of lethal and cytogenetic effects was only observed in case when embryos were placed in the caffeine solution, prior to onset of the first DNA replication in the male pronucleus. This may indicate the existence of caffeine-dependent prereplicative repair in carp embryos.     

Effects of endogenous photosensitizers on the laser-induced priming of leucocytes

The influence of He-Ne (lambda = 632.8 nm) laser irradiation on the functional activity of leucocytes was investigated. The functional activity of leucocytes irradiated in the presence of plasma with phthalocyanine raised. Irradiation of leucocytes without plasma had no influence on the chemiluminescent response of the blood cells. An increase in the concentration of phthalocyanine in plasma first led to an increase and then a decrease in the functional activity of the leucocytes. Similar results were obtained for the case of endogenous porphyrins in plasma. These results make it possible to consider the influence of laser irradiation on the leucocytes' functional activity as the priming. The basic concepts of the free-radical mechanism of laser therapy were formulated.     

氦氖激光对离体小鼠腹腔巨噬细胞功能的影响

为探索低功率激光照射治疗的机理,本实验用氦氖激光照射离体小白鼠腹腔巨噬细胞观察其吞噬鸡红细胞折功能。当照射１５分钟时,巨噬细胞蚕噬功能达到最大值,以后开始下降,照射至４０分时,巨噬细胞吞噬功能下降至对照组以下,出现抑制现象。     

The influence of electromagnetic radiation of extremely high frequencies on the pro- and antioxidant status of blood in experiments

The influence of electromagnetic radiation of extremely high frequencies in the noise mode on the level of the activity of proand antioxidant systems in a model of skin-flap ischemia was studied in vivo. Rats of the Wistar line were used in this work. The cutaneous reflex projection field of the animals was exposed once a day for 7 days in the post-operative period to electromagnetic radiation of an extremely high frequency in the range from 53.57 to 78.33 GHz with a dose of 1.2 mJ in the noise mode. The dynamics of proand antioxidant protection were compared to those of intact animals that were not irradiated. Using data on induced biochemiluminescence and estimation of malondialdehyde activity it was shown that irradiation in a course mode contributed to a decrease in the intensity of lipid peroxidation. In parallel we observed an increase in the total antioxidant reserves of blood and the activity of bioradical protection enzymes. Our findings suggest that electromagnetic radiation at extremely high frequencies in a noise mode has a regulatory impact on the state of proand antioxidant systems of the body; this can be used for the correction of postoperative ischemic disorders and the restoration of disturbed homeostasis.     

Influence of hematoporphyrin derivative concentration, incubation time, temperature during incubation and laser dose fractionation on photosensitivity of normal hemopoietic progenitors or leukemic cells

Photodynamic therapy represents a new approach for the local control of cancers. It has recently been claimed that photodynamic therapy mediated by hematoporphyrin derivative (HPD) is selectively more efficient for killing leukemic cells than normal progenitors. To improve this effect, we studied the influence of hematoporphyrin dose, temperature during incubation and/or treatment, hematoporphyrin derivative incubation time, and fractionation of the argon laser light (488-514 nm) used for hematoporphyrin stimulation. Plating efficiency calculated after a 7-day period of growth on collagen gel medium showed a dose-dependent phototoxicity of HPD reaching 0.01% for normal hemopoietic progenitors and 0.001% for leukemic cells (dose = 12.5 micrograms/ml). The 10:1 ratio of normal hemopoietic progenitors to leukemic cells was also found to be the same or increased when temperature was 37 degrees C during incubation and 4 degrees C during laser irradiation. Similar results were also found when incubation time was varied from 75-120 min, or when laser irradiation dose was fractionated into 2 or 3 periods. The ratio of normal progenitors to leukemic cells reached 100:1 when 75 J/cm2 were fractionated into 3 periods after an incubation time of 120 min with 10 micrograms/ml HPD. Selectivity in photodynamic treatment seems to occur between normal hemopoietic progenitors and leukemic cells. The mechanism of this selectivity remains unclear, but experiments with the fractionated irradiation dose suggest that as in radiotherapy, better potentially lethal damage repair in normal cells could be a factor for selectivity in photodynamic therapy. Our results obtained with leukemic cells are fully in agreement with data in the literature concerning similar experimental models.