Low-level 809 nm GaAlAs laser irradiation increases the proliferation rate of human laryngeal carcinoma cells in vitro

The aim of the study was to investigate the effect of low-level 809 nm laser irradiation on the proliferation rate of human larynx carcinoma cells in vitro. Epithelial tumor cells were obtained from a laryngeal carcinoma and cultured under standard conditions. For laser treatment the cells were spread on 96-well tissue culture plates. Sixty-six cell cultures were irradiated with an 809 nm GaAlAs laser. Another 66 served as controls. Power output was 10 mW(cw) and the time of exposure 75–300 s per well, corresponding to an energy fluence of 1.96–7.84 J/cm². Subsequent to laser treatment, the cultures were incubated for 72 h. The proliferation rate was determined by means of fluorescence activity of a redox indicator (Alamar Blue Assay) added to the cultures immediately after the respective treatment. The indicator is reduced by metabolic activity related to cellular growth. Proliferation was determined up to 72 h after laser application. The irradiated cells revealed a considerably higher proliferation activity. The differences were highly significant up to 72 h after irradiation (Mann–Whitney U test, p < 0.001). A cellular responsiveness of human laryngeal carcinoma cells to low-level laser irradiation is obvious. The cell line is therefore suitable for basic research investigations concerning the biological mechanisms of LLLT on cells.     

Evaluation of the effects of cryopreservation on viability,proliferation and colony formation of human spermatogonial stem cells in vitro culture

Proliferation of spermatogonial stem cells (SSCs) in vitro system is very important. It can enhance SSCs numbers for success of transplantation and treatment of infertility in cancer patients. In this study, testicular cells that obtained from azoospermia patients (n = 8) by enzymatic digestion were cryopreserved at the beginning and after 2 weeks of culture. Then, frozen‐thawed SSCs were co‐cultured on fresh Sertoli cells (experimental group 1), and frozen‐thawed Sertoli cells (experimental group 2) for another 3 weeks. In control group, fresh SSCs were co‐cultured on fresh Sertoli cells. Viability rate after enzymatic digestion was 93.4%±5.0. Frozen‐thawed testicular cells after 2 weeks of culture had a significantly (P < 0.05) higher percentage of living cells compared to frozen‐thawed testicular cells at the beginning of culture (59.2 ± 7.05 and 46.3 ± 8.40 respectively). The number of colonies in the experimental group 1 was significantly higher than experimental group 2 (19.6 ± 2.8 and 8.33 ± 1.5, respectively, P < 0.05). The diameter of the colonies in the experimental group 1 was significantly higher than control and experimental group 2 (P < 0.05) after 3 weeks of culture (269.7 ± 52.1, 204.34 ± 24.1 and 112.52 ± 23.5 μm, respectively). Cryopreservation technique will raise the possibility of banking SSCs for men who have a cancer‐related illness and waiting for radiotherapy and/or chemotherapy.     

Evidence for the existence of low-energy laser bioeffects on the nervous system

The reported effects of low-energy laser irradiation on the nervous system are manifested in alterations in cellular and extracellular biochemical constituents and reactions, as well as in changes in cell division rates. These bioeffects were observed in both in vivo and in vitro experiments. Other observed phenomena relate to the function of the nervous system and consist mainly of induced alteration in electrical conduction, stimulation thresholds, and behavioral effects. Clinical aspects of low-energy laser bioeffects relate mainly to pain mitigation and postponement of the posttraumatic neural degeneration processes. Many of the reported observations were obtained by experiments apparently conducted according to less than rigorous scientific criteria, and some could not be duplicated. On the whole, however, there is little doubt that low-energy laser irradiation exerts some effects on the nervous system under specific conditions of irradiation and tissue exposure via a mechanism which is probably photochemical in nature.     

Q开关Nd:YAG激光低能量祛除21例文身疗效观察

目的:探讨Q开关Nd:YAG激光多次低能量祛除文身的临床疗效观察。方法:临床选取21例文身患者,治疗采用自身对比:A区为试验区,使用Q开关1064nm波长激光,光斑直径4～6mm,能量密度为2.0～4.0J/cm2,平行均匀照射1遍,术后即刻反应皮损变白霜,无皮肤出血点,每天治疗1次,连续治疗3～4次;B区为对照区,使用Q开关1064nm波长激光,光斑直径3～4mm,能量密度为5.0～8.0J/cm2,均匀照射1遍,即刻反应皮损灰白或皮肤出血。两组病例均于术后6个月观察疗效。结果:术后6个月观察,试验区:治愈9例(42.8%),显效12例(57.2%),无瘢痕形成;对照区:治愈3例(14%),显效5例(24%),好转13例(62%),2例(9.5%)出现轻度增生性瘢痕。结论:采用Q开关Nd:YAG激光多次低能量治疗文身的方法可加快文身消退病程,减少文身治疗中能量密度过大形成瘢痕或色素脱失的风险,为文身治疗提供一种新的治疗方法。     

The effect of low level laser irradiation on adult human adipose derived stem cells

This study investigated the effect of low level laser irradiation on primary cultures of adult human adipose derived stem cells (ADSC) using a 635-nm diode laser, at 5 J/cm(2) with a power output of 50.2 mW and a power density of 5.5 mW/cm(2). Cellular morphology did not appear to change after irradiation. Using the trypan blue exclusion test, the cellular viability of irradiated cells increased by 1% at 24 h and 1.6% at 48 h but was not statistically significant. However, the increase of cellular viability as measured by ATP luminescence was statistically significant at 48 h (p < 0.05). Proliferation of irradiated cells, measured by optical density, resulted in statistically significant increases in values compared to nonirradiated cells (p < 0.05) at both time points. Western blot analysis and immunocytochemical labeling indicated an increase in the expression of stem cell marker beta1-integrin after irradiation. These results indicate that 5 J/cm(2) of laser irradiation can positively affect human adipose stem cells by increasing cellular viability, proliferation, and expression of beta1-integrin.     

Low-level laser irradiation (LLLI) promotes proliferation of mesenchymal and cardiac stem cells in culture

BACKGROUND AND OBJECTIVES: Low-level laser irradiation (LLLI) was found to promote the proliferation of various types of cells in vitro. Stem cells in general are of significance for implantation in regenerative medicine. The aim of the present study was to investigate the effect of LLLI on the proliferation of mesenchymal stem cells (MSCs) and cardiac stem cells (CSCs). STUDY DESIGN/MATERIALS AND METHODS: Isolation of MSCs and CSCs was performed. The cells were cultured and laser irradiation was applied at energy densities of 1 and 3 J/cm2. RESULTS: The number of MSCs and CSCs up to 2 and 4 weeks respectively, post-LLLI demonstrated a significant increase in the laser-treated cultures as compared to the control. CONCLUSION: The present study clearly demonstrates the ability of LLLI to promote proliferation of MSCs and CSCs in vitro. These results may have an important impact on regenerative medicine.     

Effect of low level diode laser irradiation of human oral mucosa fibroblasts in vitro

The effects of low level laser (LLL) irradiation on the proliferation of human buccal fibroblasts were studied. A standardized LLL set-up was developed (812 nm, 4.5 ± 0.5 mW/cm2). Cultures in petridishes were divided into eight groups (1 group served as control). On day 6 after seeding, routine growth medium was replaced with PBS for 1/2 hour. At the beginning of this period, LLL irradiation was performed for 0, 1, 3, 10, 32, 100, 316, or 1,000 seconds, respectively—corresponding to the radiant exposures 0, 4.5, 13.5, 45, 144, 450, 1,422, 4,500 mJ/cm2. Subsequently the cells received 3H-dT in fresh medium for 16 hours DNA-incorporation. Scintillations from tritium and total protein concentration per culture dish were determined. The individual 3H-cpm/protein-concentration ratios were calculated in % of control. Three experiments were performed (N = 151). Following LLL exposure the H-cpm/protein ratio was increased with maximum cpm/protein ratio (132.5% ± 10.6% SEM) in the group receiving 450 mJ/cm2 (P < 0.03 nonparametric Kruskal Wallis one-way ANOVA-test). This study demonstrated an increased incorporation on tritiated thymidine in cultured human oral fibroblasts following LLL exposure and suggests that LLL irradiation can induce increased DNA Synthesis. © 1994 Wiley-Liss, Inc.     

Low power laser irradiation alters gene expression of olfactory ensheathing cells in vitro

BACKGROUND AND OBJECTIVES: Both photobiomodulation (PBM) and olfactory ensheathing cells (OECs) transplantation improve recovery following spinal cord injury. However, neither the combination of these two therapies nor the effect of light on OECs has been reported. The purpose of this study was to determine the effect of light on OEC activity in vitro. MATERIALS AND METHODS: OECs were purified from adult rat olfactory bulbs and exposed to 810 nm light (150 mW; 0, 0.2, or 68 J/cm(2)). After 7-21 days in vitro, cells underwent immunocytochemistry or RNA extraction and RT-PCR. RESULTS: Analysis of immunolabeling revealed a significant decrease in fibronectin expression in the cultures receiving 68 J/cm(2). Analysis of gene expression revealed a significant (P < 0.05) increase in brain derived neurotrophic factor (BDNF), glial derived neurotrophic factor (GDNF), and collagen expression in the 0.2 J/cm(2) group in comparison to the non-irradiated and 68 J/cm(2) groups. OEC proliferation was also found to significantly increase in both light treated groups in comparison to the control group (P < 0.001). CONCLUSIONS: These results demonstrate that low and high dosages of PBM alter OEC activity, including upregulation of a number of neurotrophic growth factors and extracellular matrix proteins known to support neurite outgrowth. Therefore, the application of PBM in conjunction with OEC transplantation warrants consideration as a potential combination therapy for spinal cord injury.     

Effects of mycophenolic acid on human renal proximal and distal tubular cells in vitro.

BACKGROUND:Mycophenolic acid has been shown to be effective for the prevention and treatment of renal allograft rejection. Rejection episodes were found to be associated with an infiltration of lymphocytes and macrophages/monocytes into the diseased kidney. Expression of RANTES, HLA-DR and ICAM-1 may be important for the pathogenesis of this leukocyte infiltration. Therefore the aim of this study was to evaluate the effect of the antiproliferative and immunosuppressive agent mycophenolic acid (MPA) on cell growth and cytokine-induced expression of RANTES, HLA-DR and ICAM-1 of highly purified proximal (PTC) and distal tubular cells (DTC) from human kidney. METHODS:Human PTC and DTC were cultured in the presence of different concentrations of MPA (0.25-50 microM) or MPA plus guanosine (100 microM). Total cell number (DNA content) was determined after 4 days of cell culture by a non-radioactive fluorescence assay. Cells were stimulated by a combination of cytokines (IL1beta+gammaIFN+TNFalpha=cytomix) or cytomix plus MPA. Secretion of RANTES protein was evaluated with an enzyme-linked-immunosorbent assay. Cell surface expression of HLA-DR and ICAM-1 was assessed by flow cytometric analysis. RESULTS:MPA inhibited cell growth of PTC and DTC in a dose-dependent manner. This effect was totally abolished by the addition of guanosine. Cytokine-induced RANTES expression was synergistically increased in the presence of MPA, an effect that was partially prevented by the addition of guanosine. Cytokine stimulation resulted in de novo expression of HLA-DR and a marked increase of ICAM-1 expression, which was partially inhibited by dexamethasone. Addition of MPA did not influence this stimulated expression. CONCLUSIONS:We demonstrate that MPA has an effect on cell growth and chemokine release of tubular epithelial cells, and that these effects are dependent on the inhibition of cellular guanosine production. The clinical consequences of this possible pro-inflammatory effect of MPA on RANTES release may be abolished by a concomitant treatment with steroids.     

Choukroun’SPRF对体外培养人脂肪干细胞增殖及成骨分化的影响

目的：观察自体富血小板纤维蛋白Choukroun＇s PRF（Choukroun＇s platelct-rich fibrin）对体外培养人脂肪来源干细胞（adipose-derived stem cells,ADSCs）增殖及成骨分化能力的影响。方法：取吸脂术者自愿捐献的脂肪组织分离培养ADSCs,采用Choukroun法制备自体PRF备用,观察细胞生长情况。取第3代ADSCs分别向骨细胞、脂肪细胞、神经球细胞定向诱导分化鉴定,并行细胞表面抗原CD29、CD45、CD90流式检测鉴定。将第3代ADSCs分别采用含PRF的普通培养基（PRF组Ⅰ）和不含PRF的普通培养基（对照组Ⅰ）进行培养,观察细胞生长情况,培养1天、3天、5天、7天后采用CCK-8试剂检测细胞增殖活性。另外分别采用含PRF的成骨诱导培养基（PRF组Ⅱ）、不含PRF的成骨诱导培养基（对照组Ⅱ）及不合PRF的普通培养基（空白组）进行培养,第7天、14天、21天、28天行碱性磷酸酶活性（ALP活性）检测;诱导细胞培养后第7天、14天天各组分别行von Kossa染色观察钙结节形成情况。结果：第3代ADSCs倒置显微镜下观察大多呈梭形,向骨细胞、脂肪细胞、神经干细胞定向诱导鉴定均为阳性,流式检测鉴定CD29、CD90为阳性,CD45为阴性。CCK-8法示PRF组Ⅰ的0D值均大于对照组Ⅰ,两组比较差异均有统计学意义（P〈0．01）。ALP活性检测示PRF组Ⅱ第7天、14天、21天、28天细胞活性较对照组Ⅱ均大,两组比较差异均有统计学意义（P〈0．01）。PRF组Ⅱ成骨诱导7天后vonKossa染色阳性;14天后阳性细胞增多,对照组Ⅱ诱导7天未见钙结节,14天见少量阳性钙结节,空白组培养14天未见黑色钙结节。结论：Choukroun’sPRF明显促进脂肪干细胞增殖及成骨分化,为骨组织工程提供了新的技术。PRF与干细胞共同培养可能还有许多潜在的临床及生物工程应用价值,值得进一步研究。     

UVB照射对PIG1细胞增殖活性的影响

目的：探讨UVB照射对正常人黑素细胞PIG1细胞形态及增殖活性的影响。方法：取对数生长期的PIG1细胞,分别以50、100、200、300、400、500、600和700mJ/cm2剂量的UVB照射后继续培养0h、24h和48h,在倒置显微镜下观察其形态学变化,用MTT法检测UVB照射对细胞增殖活性的影响。结果：在50～200 mJ/cm2的UVB辐射下,随辐射剂量的增大,PIG1细胞的增殖活性逐渐增加,倒置相差显微镜从形态学上证实了一定剂量的UVB照射可以促进细胞增殖。结论：一定剂量的UVB照射有刺激PIG1细胞增殖及树突生长的作用。     

前癃通胶囊对体外人前列腺基质细胞增殖的影响

目的在临床基础和动物实验研究的基础上,进一步探讨前癃通胶囊对前列腺基质细胞增殖的影响.方法进行体外培养人前列腺基质细胞,并采用四氮唑蓝法(MTT)检测细胞增殖的影响(波长630nm).结果前癃通胶囊低、中、高浓度组的OD值在24h、48h、72h时明显低于细胞空白对照组(P＜0.01),且与药物浓度呈剂量依赖性;低浓度组的OD值在72h点明显低于细胞空白对照组(P＜0.05),在24h、48h点与细胞空白对照组相比无明显差异(P＞0.05).结论前癃通胶囊能抑制体外培养的前列腺基质细胞的增殖,这种作用呈剂量依赖性.     

Effect of low-power He-Ne laser irradiation on rabbit articular chondrocytes in vitro

BACKGROUND AND OBJECTIVES: In the orthopaedic field, the repair of articular cartilage is still a difficult problem, because of the physiological characters of cartilaginous tissues and chondrocytes. To find an effective method of stimulating their regeneration, this in vitro study focuses on the biostimulation of rabbit articular chondrocytes by low-power He-Ne laser. STUDY DESIGN/MATERIALS AND METHODS: The articular chondrocytes isolated from the cartilage of the medial condyle of the femur of the rabbit were incubated in DMEM/HamF(12) medium. The second passage culture were spread on 24 petri dishes and were irradiated with laser at power output of 2-12 mW for 6.5 minutes, corresponding to the energy density of 1-6 J/cm(2). Laser treatment was performed three times at a 24-hour interval. After lasering, incubation was continued for 24 hours. Non-irradiated cells were kept under the same conditions as the irradiated ones. The cell proliferation activity was evaluated with a XTT colorimetric method and the cell secretion activity was analyzed by metachromasia and immunocytochemistry. RESULTS: Irradiation of 4-6 J/cm(2) increased the cell numbers and revealed a considerably higher cell proliferation activity comparing to control cultures. Thereinto, the energy density of 4 and 5 J/cm(2) remarkably increased cell growth, with positive effect on synthesis and secretion of extracellular matrix. CONCLUSIONS: The present study showed that a particular laser irradiation stimulates articular chondrocytes proliferation and secretion. These findings might be clinically relevant, indicating that low-power laser irradiation treatment is likely to achieve the repair of articular cartilage in clinic.     

P-glycoprotein-expressing tumor cells are resistance to anticancer drugs in human gastrointestinal cancer

The resistance to doxorubicin (DOX) by some tumor cells is mainly due to the effect of P-glycoprotein encoded by the multidrug resistance-1 (mdr1) gene. We tried to prove the correlations between P-glycoprotein expression and the sensitivity for anticancer drugs including DOX and other cytotoxic drugs that are currently used for gastrointestinal cancer patients. We quantified the P-glycoprotein expression by flow cytometry techniques, and the sensitivity for anticancer drugs using a tetrazolium salt, 3-(4,5-di-methylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), assay in highly purified fresh human tumor cells obtained from 25 cancer patients. The inhibition rates were the lowest in DOX and mitomycin C (MMC), compared with other drugs. The most significant correlation between DOX and MMC was seen in the inhibition rates. A significant correlation was also seen between the inhibition rates for DOX and P-glycoprotein expression, whereas only a slight correlation between the sensitivity for MMC and P-glycoprotein expression was observed. We should therefore pay close attention to the effect of P-glycoprotein when treating cancer patients, especially if both the inhibition rates of DOX and MMC are low based on the findings of an MTT assay.     

Transcranial application of low-energy laser irradiation improves neurological deficits in rats following acute stroke

BACKGROUND AND OBJECTIVES: Low-level laser therapy (LLLT) has been shown to have beneficial effects on ischemic skeletal and heart muscles tissues. The aim of the present study was to approve the effectiveness of LLLT treatment at different locations on the brain in acute stroked rats. STUDY DESIGN/MATERIALS AND METHODS: Stroke was induced in 169 rats that were divided into four groups: control non-laser and three laser-treated groups where laser was employed ipsilateral, contralateral, and both to the side of the induced stroke. Rats were tested for neurological function. RESULTS: In all three laser-treated groups, a marked and significant improvement in neurological deficits was evident at 14, 21, and 28 days post stroke relative to the non-treated group. CONCLUSIONS: These observations suggest that LLLT applied at different locations in the skull and in a rather delayed-phase post stroke effectively improves neurological function after acute stroke in rats.