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.     

Biostimulation of wound healing in rats by combined soft and middle power lasers

For some time now, the combined soft- and middle-power laser has been used for treating wounds and various skin diseases, but its effect has not yet been confirmed in experiments on animals. For this reason, a controlled test on the effect of this laser on wound healing in rats was conducted. In 16 rats, 3-cm long skin incisions were made on the wall of the abdomen and then sutured using standard surgical technique with 5 stitches. Eight rats were then treated with laser light, the other 8 receiving a control treatment. The wounds were photographed on the 1st, 2nd, 3rd, 5th, 8th and 15th postoperative day. The photographs were shown to 10 doctors who rated the wounds from 1 to 4 on the basis of the criteria inflammation and adaptation. While the wounds of the laser group were not judged to be significantly better than those of the control group in terms of inflammation, adaptation was judged to be significantly better in the laser-treated group. This effect was particularly evident at the beginning of treatment (3rd day: average rating of laser group: 1.68; S = 0.32; control group: 2.41; S = 0.53; analysis of variance parameters for repeated measurements: p = 0.027 less than 0.05). These results demonstrate that in all probability the combined soft- and middle-power laser promotes the closing of wounds in rats, especially in the first postoperative days, while there is no positive effect on inflammation.     

The role of endogenous porphyrins in laser therapy of experimental skin wounds

The role of endogenous porphyrins in the effect of laser irradiation on the superoxide dismutase (SOD) activity of wound exudate and rat leukocyte activity has been studied on models of aseptic incised skin wounds. Wounds were irradiated with a He-Ne laser (632.8 nm, 1.5 J/cm²) on the 2nd, 3rd, and 4th days after the beginning of the experiment. Irradiation effects were evaluated by the SOD activity (NBT test) and the activity of leukocytes of the wound exudate (as a chemiluminescent response to opsonized zymosan). It was found that in animals subjected to laser irradiation, the SOD activity sharply increased. This effect depended on endogenous porphyrin concentration and was retained throughout the experiment. The SOD activity in unirradiated animals decreased from the 2nd to the 5th day of experiment. The evaluation of the activity of wound exudate leukocytes did not reveal any distinct dependence of the effect on the concentration of endogenous porphyrins.     

The effect of low-energy laser on skin-flap survival in the rat and porcine animal models.

Low-energy lasers are currently being used in the therapy of rheumatoid arthritis, chronic pain, muscle strain, and the promotion of wound healing in human and veterinary medicine. This study examined the effects of low-energy laser on skin-flap survival in a controlled interspecies study using the rat and porcine models. Twenty dorsal skin flaps based caudally were performed in 20 rats (10 laser-treated and 10 control flaps). The wounds were closed, and the flaps were sutured over the skin. Forty dorsal pig skin flaps based medially were raised in five pigs. The flaps were treated once per day for 10 days: 4 days preoperatively, the day of surgery, and 5 days postoperatively (30 s/cm3 per day). The average surviving rat flap surface area for the laser-treated flaps was 653 +/- 112 mm (mean +/- SD) and 580 +/- 60 mm in the control flaps, which was not significant (p greater than 0.05). In the porcine model, the average surviving area for the 20 laser-treated flaps was 949 +/- 174 mm, and the control average (n = 20) was 969 +/- 147 mm, also not significant. No beneficial effect was seen with low-energy laser preoperative and postoperative treatment of skin flaps in the rat and porcine models.     

Acceleration of healing,reduction of fibrotic scar,and normalization of tissue architecture by an angiotensin analogue,NorLeu3-A(1-7)

Angiotensin peptides have been demonstrated to modulate cellular proliferation, angiogenesis, and dermal repair. In this report, the effects of an analogue of the active angiotensin peptide angiotensin(1-7), namely norLeu3-angiotensin(1-7) (NorLeu3-A(1-7)), on the healing of epithelial wounds are presented. Three models were used to evaluate the normal (rats) and delayed (diabetic mice) healing responses of full-thickness excision wounds and the healing responses of full-thickness incision wounds (rats). NorLeu3-A(1-7) was superior to the naturally occurring angiotensin peptide angiotensin(1-7) and to Regranex (Ortho McNeil, Somerville, N.J.) (a formulation of recombinant platelet-derived growth factor used clinically for the treatment of diabetic ulcers) in accelerating tissue repair. By day 9 (normal rats) and day 11 (diabetic mice), the differences in the rates of closure of full-thickness excision wounds between NorLeu3-A(1-7) and Regranex were statistically significant (n = 5 per group). Full healing was observed for 60 percent of the diabetic mice treated topically with NorLeu3-A(1-7) by day 18 after injury, at which time full healing of wounds on placebo-treated or Regranex-treated diabetic mice was not observed. In the rat incision model, accelerated healing and reduced gross appearance of scarification were observed. Administration of NorLeu3-A(1-7) reduced fibrosis and scarring in the healing wounds. This action was more pronounced with longer administration of the peptide after injury. In fact, if systemic administration of the peptide (NorLeu3-A(1-7)) was continued during the remodeling phase, then the formation of new adnexal structures at the center of full-thickness excision wounds was observed, with an increase in the appearance of small immature hair follicles at the sites of the excision wounds. The action of this peptide was blocked by the AT receptor antagonist d-Ala7-angiotensin(1-7), which suggests that this receptor is involved in the healing responses to exogenous NorLeu3-A(1-7). These data suggest that this novel angiotensin peptide has the potential to be of benefit in accelerating wound repair and reducing scar formation.     

低功率He-Ne激光照射下细胞内活性氧自由基的产生和游离Ca^2＋浓度的研究

在临床应用中,低功率He-Ne激光(632.8 nm)能促进骨骼肌修复,加速创伤愈合,降低牙齿的超敏感性,减缓疼痛等.大量研究表明:低功率He-Ne激光能调节细胞的众多行为,如细胞增殖、分泌、迁移、粘附、蛋白质合成和基因表达等.但低功率He-Ne激光调节细胞行为的分子机制并未阐明,考察低功率He-Ne激光照射后细胞内活性氧自由基的产生水平和游离ca2 浓度是否会发生变化,通过激光扫描共聚焦显微镜,分别利用H:DCFDA和Fluo-3/AM这两种荧光探针,检测到经He-Ne激光照射后,肺腺癌细胞内活性氧自由基的水平上调以及游离Ca2 浓度增加.该研究为低功率He-Ne激光的生物光刺激效应提供了可能的分子机理.     

氦氖激光对大鼠心肌超微结构、SOD和MDA影响的观察

为了解低强度氦氖激光对心肌细胞超微结构、超氧化物歧化酶（SOD）和丙二醛（MDA）的影响,采用2．87J／cm^2,7.17J/cm^2和28.66J/cm^2三种剂量氦氖激光照射大鼠心前区,电镜观察心肌超微结构,测定心肌组织SOD和MDA的含量。结果发现心肌线粒体有轻微损伤,心肌组织SOD含量在7．17J／cm^2剂量显著下降（P＜0．05）,而在28．66J／cm^2剂量显著升高（P＜0．05）,心肌组织MDA含量在7．17J／cm^2和28．66J／cm^2两种剂量下降有显著升高（P＜0．01）,在2．87J／cm^2剂量,心肌组织SOD和MDA含量均无显著变化（P＜0．05）。结果提示心肌SOD含量和脂质过氧化随不同的激光剂量而变化。     

Demonstration of elevated type I and type III procollagen mRNA levels in cutaneous wounds treated with helium-neon laser. Proposed mechanism for enhanced wound healing

To assess laser modulation of wound healing, full-thickness cutaneous wounds were produced in the backs of pigs, and subjected to treatment with helium-neon laser. For comparison, some wounds were treated with non-laser energy source (a tungsten light) or left untreated as controls. Type I and type III procollagen mRNA levels were determined in the wounds by molecular hybridization with cDNA probes. The results indicated that type I and type III mRNA levels were markedly increased at days 17 and 28 of the healing in wounds treated with He-Ne laser, when compared to control or tungsten light-treated wounds. The results suggest that helium-neon laser stimulates wound healing by enhancing procollagen gene expression. These observations may have relevance to previous clinical studies suggesting that helium-neon laser stimulates wound healing.     

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。     

Modulation of macrophage phenotype by soluble product(s) released from neutrophils

The regulation of macrophage phenotype by neutrophils was studied in the s.c. polyvinyl alcohol sponge wound model in mice made neutropenic by anti-Gr-1 Ab, as well as in cell culture. Wounds in neutropenic mice contained 100-fold fewer neutrophils than those in nonneutropenic controls 1 day after sponge implantation. Wound fluids from neutropenic mice contained 68% more TNF-alpha, 168% more IL-6, and 61% less TGF-beta1 than those from controls. Wound fluid IL-10 was not different between the two groups, and IL-4 was not detected. Intracellular TNF-alpha staining was greater in cells isolated from neutropenic wounds than in those from control wounds. The hypothesis that wound neutrophil products modulate macrophage phenotype was tested in Transwell cocultures of LPS-stimulated J774A.1 macrophages and day 1 wound cells (84% neutrophils/15% macrophages). Overnight cocultures accumulated 60% less TNF-alpha and IL-6 than cultures of J774A.1 alone. The suppression of cytokine release was mediated by a soluble factor(s), because culture supernatants from wound cells inhibited TNF-alpha and IL-6 release from LPS-stimulated J774A.1 cells. Culture supernatants from purified wound neutrophils equally suppressed TNF-alpha release from LPS-stimulated J774A.1 cells. Wound cell supernatants also suppressed TNF-alpha and superoxide release from murine peritoneal macrophages. The TNF-alpha inhibitory factor has a molecular mass <3000 Da and is neither PGE2 nor adenosine. The present findings confirm a role for neutrophils in the regulation of innate immune responses through modulation of macrophage phenotype.     

全身放射损伤对皮肤伤口成纤维细胞参与组织修复能力的影响

合并全身放射损伤的创伤（放创复合伤）是一种重要而有代表性的难愈性创伤,其难愈机制尚未完全阐明,成纤维细胞是最为重要的组织修复细胞,其辐射敏感性较低,为了明确放创复合伤时合并的放射损伤是否对伤口成纤维细胞有直接损伤作用,以及这些损伤作用对创伤愈合的影响,实验检测了分离,培养的放创复合伤和单纯创伤大鼠皮肤伤口成纤维细胞的增殖,凋亡及其他反映其参与组织修复能力的指标变化,结果发现,在去除全身因素和局部因素,特别是创伤局部细胞因子和细胞外基质对成纤维细胞的反馈作用后,放创复合伤组伤口成纤维细胞增殖力,贴壁力和粘附力均显著弱于单纯创伤组,而成纤维细胞的凋亡率则显著增加,这些细胞表明,全身放射损伤对伤口成纤维细胞有直接损伤作用,使其参与组织修复能力显著受抑,这是合并全身放射损伤时创伤难愈的重要原因。     

Healing of burns after treatment with 670-nanometer low-power laser light

Recent investigations have reported contradictory results on the influence of low-power laser light on wound healing. Low-power laser with a power output of 250 mW and an emitted laser light of 670 nm have been insufficiently investigated to date. The effect of a 250-mW/670-nm laser light on the healing of burning wounds in rats was investigated. Thirty rats were burned on both flanks. One wound was irradiated with 670-nm laser light (2 J/cm2), whereas the other side remained untreated. Macroscopic evaluation of the wounds was performed daily; 10, 20, and 30 days after burning, 10 rats were killed and the wounds histologically evaluated. Neither macroscopic nor histologic examination of the irradiated wound showed accelerated wound healing when compared with control wounds. In the present study, irradiation of burns with a 250-mW/670-nm laser light produced no beneficial effects on wound-healing processes.     

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.     

He—Ne激光照射离体鼠巨噬细胞对线粒体跨膜电势的影响

目的：研究Ｈｅ－Ｎｅ激光照射鼠巨噬细胞对线粒体跨膜电势的影响,及其与激光剂量的关系。方法：用亲脂性阳离子荧光染料Ｒｈｏｄａｍｉｎｅ１２３对鼠巨噬细胞线粒体作荧光标记,以不同的激光剂量照射,采用图像分析系统（ＩＡＳ）和荧光显微镜观察线粒体跨膜电势荧光强度的变化。结果：低功率Ｈｅ－Ｎｅ激光照射５,１０,１５ｍｉｎ,激光剂量分别为０．６４９,１．３８８和２．０８２Ｊ／ｃｍ＾２,巨噬细胞线粒体跨膜电势荧光     

低强度He-Ne激光照射人外周血淋巴细胞两组试验结果的分析

本文采用染色体畸变 (chromosomalaberration CA)试验和微核 (micronucleus)试验两种方法对低强度He Ne激光辐照育龄妇女外周血淋巴细胞。激光能量密度分别为 14.31J cm2 (辐照 5′)、2 8.6 2J cm2 (辐照 10′) ,5 7.2 4J cm2(辐照 2 0′) ,114.5 2J cm2 (辐照 40′)。照射血样后 ,染色体畸变试验检测其淋巴细胞染色体畸变率 ,激光照射及空白对照组 ,血样染色体畸变率分别为 4.2 9‰、3.96‰、3.81、3.5 9‰和 4.19‰ ,X2 检验无显著意义 (P >0 .0 5 )。阳性对照丝裂霉素MMC处理的血样淋巴细胞CA率平均为 14.41‰ ,明显高于激光照射和空白对照组 ,X2 检验有显著差异(P <0 .0 1)。微核试验检测结果 ,微核染色体分别为 1.0 2‰ ,1.17‰ ,1.18‰ ,1.31‰和 1.19‰对照 ,经统计分析激光照射各组与对照组微核率均在 2‰以下 (P >0 .0 5 ) ,属正常人体微核范围内。结果显示两组试验监测诱变均具有一致性。证明He Ne激光辐照人体细胞对染色体无致畸效应。且表明He Ne激光在治疗范围内应用安全、有效、不会对不体造成危害。     

Acute ethanol exposure impairs angiogenesis and the proliferative phase of wound healing

Acute ethanol exposure represents an increased risk factor for morbidity and mortality associated with surgical or traumatic injury. Despite clinical observations suggesting that ethanol exposure before injury alters tissue repair processes, little direct evidence about the mechanism by which ethanol affects the wound healing process is available. In this study, excisional wounds from female BALB/c mice with or without circulating ethanol levels of 100 mg/dl were used to assess wound closure, angiogenesis, and collagen content. Ethanol exposure resulted in a significant but transient delay in wound closure at day 2 postwounding (28 +/- 4% vs. 17 +/- 1%). In addition, total collagen content was significantly reduced by up to 37% in wounds from ethanol-treated mice compared with controls. The most significant effect of ethanol exposure on wounds was on vascularity because angiogenesis was reduced by up to 61% in wounds from ethanol-treated mice. The reduction in vessel density occurred despite near-normal levels of proangiogenic factors VEGF and FGF-2, suggesting a direct effect of ethanol exposure on endothelial cell function. Further evidence for a direct effect was observed in an in vitro angiogenesis assay because the exposure of endothelial cells to ethanol reduced angiogenic responsiveness to just 8.33% of control in a cord-forming assay. These studies provide novel information regarding the effect of a single dose of ethanol on multiple parameters of the wound healing process in vivo and suggest a potential mechanism by which ethanol impairs healing after traumatic injury.     

烧烫伤创面感染的小鼠模型构建

目的探讨一种简单、稳定的烧烫伤创面感染的小鼠模型构建方法,以便进行相关烧烫伤创面修复研究。方法取30只BALB/c小鼠,采用自制木质烫伤板,沸水浴法烫取直径8 mm的圆形创面,烫伤时间分别为5 s、10 s、15 s。伤后48 h,取创面组织进行HE染色观察,筛选最佳创面烫伤时间。另取72只小鼠制成深Ⅱ度烫伤创面,采用擦刮法分别接种20μL菌浓度为1×106、l×107、1×108CFU/mL金黄色葡萄球菌标准菌株ATCC 25923的菌液。接种细菌后72 h,取创面组织HE染色观察创面炎症反应情况,并测定3、7、14 d的皮肤菌负荷,筛选最佳的细菌接种浓度。最后,按最佳条件建模后,观察创面的完全愈合时间以及创面愈中、愈后的组织学变化,以确定此创面感染模型是否建立成功。结果组织学结果表明,10 s为深Ⅱ度创面的理想致伤时间,最佳接种菌浓度为l×108CFU/mL,此时期,14 d内菌负荷均高于l×105CFU/g。该模型的创面愈合时间(21±0.95 d)较正常创面愈合时间(15.92±0.34 d)明显延长(P<0.01),炎性反应明显,愈后不佳。结论烧烫伤创面感染的小鼠模型构建成功,可作为感染创面防治研究的实验动物模型。     

Effect of sodium diphenylhydantoin on skin wound healing in rats

This study evaluated the effect of phenytoin (sodium diphenylhydantoin) on skin wound healing in a rat model. The study was divided into two parts. In part I, 20 mul of phenytoin (10 mg/ml) was subcutaneously injected into the 3-cm dorsal full-thickness incisional wounds of 14 rats on postoperative days 0, 3, and 6. Twelve rats that received saline injections were used as the controls. The skin samples were harvested and tested for tensile strength and histology. An additional 12 rats with the same incisional wounds were tested for chemokine gene expressions. In part II, 20 mul of phenytoin (10 mg/ml) was applied topically once a day on a 4 x 4 cm area of the open dorsal wounds of 10 rats. Saline was applied to the wounds of the 10 control group rats. The wounds were measured weekly. The results showed that the average tensile strength of the phenytoin-treated wound was 0.49 +/- 0.08 MPa compared with the control group at 0.02 +/- 0.01 MPa (p < 0.05). The density ratio of chemokine monocyte chemotactic protein (MCP-1) to beta-actin in the phenytoin-treated group was also significantly higher than in the control group (p < 0.05). Histologic analysis of the phenytoin group showed a large amount of fibroblast proliferation, collagen synthesis, and neovascularization. Phenytoin-treated wounds were also smaller at 1 to 6 weeks postoperatively than the control group wounds. The authors conclude that the administration of phenytoin can promote wound healing and significantly increase MCP-1 expression. Phenytoin-treated wounds showed significant increase in collagen deposition and neovascularization, which resulted in an increased wound tensile strength and accelerated healing of both open and closed wounds.     

Does the light of soft lasers or of combination soft and middle-power lasers improve wound healing in rats? Continuing studies

In recent years, soft and middle-power lasers have been employed in the treatment of wounds and various dermatoses, but as yet no experimental confirmation of their effects has come available. However, we have been able to show in a recent study that light from combined soft and middle-power lasers applied on postoperative days 1, 2, 3, 5 and 8 has a positive effect on wound healing in rats. The present study was intended to clarify the influence of the type of laser light and treatment duration under controlled conditions. In 24 rats, a 3-cm incision was made in the abdominal wall and sutured with 5 single knots. Eight of the animals served as controls, while the remaining animals were treated with laser light, 8 with a soft laser for 10 min/day on postoperative days 2, 3, 5, 8 and 15, the other 8 for 20 min. on day 1 only with combined soft and middle-power lasers. The wounds were photographed on post-operative days 1, 2, 3, 5, 8 and 15. 10 independent observers rated the photographs on a scale of 1 to 4 on the basis of edge approximation and absence of inflammation. Soft laser light alone did not improve wound healing as judged by these criteria. Nor did a single dose of combined soft and middle-power laser light have any statistically significant effect.     

激光辐射公牛精液效应的研究

用不同剂量的激光辐射公牛的离体精液,发现低剂量的氦氖激光可以提高精子的活力、顶体完整率和顶体反应率,降低精液中的钙含量,表明激光能改善公牛的精液品质,可应用于养牛生产中。