***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The use of low levels of visible or near infrared light for reducing pain , inflammation and edema , promoting healing of wounds , deeper tissues and nerves , and preventing cell death and tissue damage has been known for over forty years since the invention of lasers . Despite many reports of positive findings from experiments conducted in vitro , in animal models and in r and omized controlled clinical trials , LLLT remains controversial in mainstream medicine . The biochemical mechanisms underlying the positive effects are incompletely understood , and the complexity of rationally choosing amongst a large number of illumination parameters such as wavelength , fluence , power density , pulse structure and treatment timing has led to the publication of a number of negative studies as well as many positive ones . A biphasic dose response has been frequently observed where low levels of light have a much better effect on stimulating and repairing tissues than higher levels of light . The so-called Arndt-Schulz curve is frequently used to describe this biphasic dose response . This review will cover the molecular and cellular mechanisms in LLLT , and describe some of our recent results in vitro and in vivo that provide scientific explanations for this biphasic dose response BACKGROUND Experimental evidence suggests that cyclosporine , which inhibits the opening of mitochondrial permeability-transition pores , attenuates lethal myocardial injury that occurs at the time of reperfusion . In this pilot trial , we sought to determine whether the administration of cyclosporine at the time of percutaneous coronary intervention ( PCI ) would limit the size of the infa rct during acute myocardial infa rct ion . METHODS We r and omly assigned 58 patients who presented with acute ST-elevation myocardial infa rct ion to receive either an intravenous bolus of 2.5 mg of cyclosporine per kilogram of body weight ( cyclosporine group ) or normal saline ( control group ) immediately before undergoing PCI .  Infa rct size was assessed in all patients by measuring the release of creatine kinase and troponin I and in a subgroup of 27 patients by performing magnetic resonance imaging ( MRI ) on day 5 after infa rct ion . RESULTS The cyclosporine and control groups were similar with respect to ischemia time , the size of the area at risk , and the ejection fraction before PCI . The release of creatine kinase was significantly reduced in the cyclosporine group as compared with the control group ( P=0.04 ) . The release of troponin I was not significantly reduced ( P=0.15 ) . On day 5 , the absolute mass of the area of hyperenhancement ( i.e. , infa rct ed tissue ) on MRI was significantly reduced in the cyclosporine group as compared with the control group , with a median of 37 g ( interquartile range , 21 to 51 ) versus 46 g ( interquartile range , 20 to 65 ; P=0.04 ) . No adverse effects of cyclosporine administration were detected . CONCLUSIONS In our small , pilot trial , administration of cyclosporine at the time of reperfusion was associated with a smaller infa rct by some measures than that seen with placebo . These data are preliminary and require confirmation in a larger clinical trial Background Remote ischemic preconditioning ( RIPC ) has been shown to enhance the tolerance of remote organs to cope with a subsequent ischemic event . We hypothesized that RIPC reduces postoperative neurocognitive dysfunction ( POCD ) in patients undergoing complex cardiac surgery . Methods We conducted a prospect i ve , r and omized , double-blind , controlled trial including 180 adult patients undergoing elective cardiac surgery with cardiopulmonary bypass . Patients were r and omized either to RIPC or to control group . Primary endpoint was postoperative neurocognitive dysfunction 5–7 days after surgery assessed by a comprehensive test battery . Cognitive change was assumed if the preoperative to postoperative difference in 2 or more tasks assessing different cognitive domains exceeded more than one SD ( 1 SD criterion ) or if the combined Z score was 1.96 or greater ( Z score criterion ) . Results According to 1 SD criterion , 52 % of control and 46 % of RIPC patients had cognitive deterioration 5–7 days after surgery ( p = 0.753 ) . The summarized Z score showed a trend to more cognitive decline in the control group ( 2.16±5.30 ) compared to the RIPC group ( 1.14±4.02 ; p = 0.228 ) . Three months after surgery , incidence and severity of neurocognitive dysfunction did not differ between control and RIPC . RIPC tended to decrease postoperative troponin T release at both 12 hours [ 0.60 ( 0.19–1.94 ) µg/L vs. 0.48 ( 0.07–1.84 ) µg/L ] and 24 hours after surgery [ 0.36 ( 0.14–1.89 ) µg/L vs. 0.26 ( 0.07–0.90 ) µg/L ] . Conclusions We failed to demonstrate efficacy of a RIPC protocol with respect to incidence and severity of POCD and secondary outcome variables in patients undergoing a wide range of cardiac surgery . Therefore , definitive large-scale multicenter trials are needed . Trial Registration Clinical Trials.gov OBJECTIVE The aim of this r and omized , placebo-controlled , double-blind trial was to investigate changes in the content of 10 cytokines in the human peripheral blood after transcutaneous and in vitro irradiation with polychromatic visible and infrared ( IR ) polarized light at therapeutic dose . BACKGROUND DATA The role of cytokines in development of anti-inflammatory , immunomodulatory , and wound-healing effects of visible and IR light remains poorly studied . METHODS The sacral area of volunteers was exposed ( 480 - 3400 nm , 95 % polarization , 12 J/cm(2 ) ) ; in parallel , the blood sample s of the same subjects were irradiated in vitro ( 2.4 J/cm(2 ) ) . Determination of cytokine content was performed using enzyme-linked immunosorbent assay ( ELISA ) . RESULTS A dramatic decrease in the level of pro-inflammatory cytokines TNF-alpha , IL-6 , and IFN-gamma was revealed : at 0.5 h after exposure of volunteers ( with the initial parameters exceeding the norm ) , the cytokine contents fell , on average , 34 , 12 , and 1.5 times . The reduced concentrations of TNF-alpha and IL-6 were preserved after four daily exposures , whereas levels of IFN-gamma and IL-12 decreased five and 15 times . At 0.5 h and at later times , the amount of anti-inflammatory cytokines was found to rise : that of IL-10 rose 2.7 - 3.5 times ( in subjects with normal initial parameters ) and of TGF-beta1 1.4 - 1.5 times ( in the cases of its decreased level ) . A peculiarity of the light effect was a fast rise of IFN-gamma at 3.3 - 4.0 times in subjects with normal initial values . The content of IL-1beta , IL-2 , IFN-alpha , and IL-4 did not change . Similar regularities of the light effects were recorded after in vitro irradiation of blood , as well as on mixing the irradiated and non-irradiated autologous blood at a volume ratio 1:10 ( i.e. , at modeling the events in a vascular bed of the exposed person when a small amount of the transcutaneously photomodified blood contacts its main circulating volume ) . CONCLUSION Exposure of a small area of the human body to light leads to a fast decrease in the elevated pro-inflammatory cytokine plasma content and to an increase in the the anti-inflammatory factor concentration , which may be an important mechanism of the anti-inflammatory effect of phototherapy . These changes result from transcutaneous photomodification of a small volume of blood and a fast transfer of the light-induced changes to the entire pool of circulating blood Abstract We suggested that low-level laser irradiation ( LLLI ) precondition prior to cell transplantation might remodel the hostile milieu of infa rct ed myocardium and subsequently enhance early survival and therapeutic potential of implanted bone marrow mesenchymal stem cells ( BMSCs ) . Therefore , in this study we wanted to address : ( 1 ) whether LLLI pre-treatment change the local cardiac micro-environment after myocardial infa rct ion ( MI ) and ( 2 ) whether the LLLI preconditions enhance early cell survival and thus improve therapeutic angiogenesis and heart function .  MI was induced by left anterior descending artery ligation in female rats . A 635 nm , 5 mW diode laser was performed with energy density of 0.96 J/cm2 for 150 sec. for the purpose of myocardial precondition . Three weeks later , qualified rats were r and omly received with LLLI precondition ( n= 26 ) or without LLLI precondition ( n= 27 ) for LLLI precondition study . Rats that received thoracotomy without coronary ligation were served as sham group ( n= 24 ) . In the cell survival study , rats were r and omly divided into 4 groups : serum-free culture media injection ( n= 8) , LLLI precondition and culture media injection ( n= 8) , 2 million male BMSCs transplantation without LLLI pre-treatment ( n= 26 ) and 2 million male BMSCs transplantation with LLLI precondition ( n= 25 ) group , respectively . Vascular endothelial growth factor ( VEGF ) , glucose-regulated protein 78 ( GRP78 ) , superoxide dismutase ( SOD ) and malondialdehyde ( MDA ) in the infa rct ed myocardium were evaluated by Western blotting , real-time PCR and colorimetry , respectively , at 1 hr , 1 day and 1 week after laser irradiation . Cell survival was assayed with quantitative real-time PCR to identify Y chromosome gene and apoptosis was assayed with transferase-mediated dUTP end labelling staining . Capillary density , myogenic differentiation and left ventricular function were tested by immunohistochemistry and echocardiography , respectively , at 1 week . After LLLI precondition , increased VEGF and GRP78 expression , as well as the enhanced SOD activity and inhibited MDA production , was observed . Compared with BMSC transplantation and culture media injection group , although there was no difference in the improved heart function and myogenic differentiation , LLLI precondition significantly enhanced early cell survival rate by 2-fold , decreased the apoptotic percentage of implanted BMSCs in infa rct ed myocardium and thus increased the number of newly formed capillaries . Taken together , LLLI precondition could be a novel non-invasive approach for intraoperative cell transplantation to enhance cell early survival and therapeutic potential The angioplasty procedure is associated with a release of numerous factors triggering the local inflammatory reaction in vascular wall and leading thus to the restenosis . In this study , we hypothesize that the low-energy laser irradiation may exert beneficial effect by limiting this process . A group of 101 subjects ( 75 men and 26 women , mean age : 59.1 ± 10.3 ) treated with percutaneous coronary intervention ( PCI ) , were recruited to this study . While 52 patients ( 40 men and 12 women ) were subjected to the intravascular low-energy laser irradiation ( λ = 808 nm ) of dilated lesion during the PCI , the remaining patients ( 35 men and 14 women ) constituted the control group . The levels of interleukin 1β , 6 and 10 ( IL 1β , IL 6 and IL 10 ) were measured immediately before the procedure , and then at the 6th , 12th hour as well as after 1 month following the PCI . Significantly lower levels of IL 1β and IL 6 in the irradiated group during each analysis after the procedure were observed . Moreover , significantly lower IL 10 level in irradiated group within 6 and 12 hours after PCI was observed . Irradiation of the lesion with low-energy laser radiation during the PCI procedure results in a decrease in the levels of pro-inflammatory IL 1β and IL 6 as well as in an increase in the levels of anti-inflammatory IL 10 , which may result in decreased risk for restenosis Objectives The usefulness and safety of percutaneous myocardial laser therapy in selected patients have been identified in previous 1-year r and omized trial reports , including that from a double-blind , sham-controlled trial we independently conducted . We aim ed to determine whether the 1-year effects are maintained through a long-term , longitudinal follow-up . Methods Patients ( n=77 ) with chronic , stable , medically refractory angina ( class III or IV ) not amenable to conventional revascularization and with evidence of reversible ischemia , ejection fraction ≥25 % , and myocardial wall thickness ≥8 mm were treated with percutaneous myocardial laser . After the 1-year follow-up and disclosure of all r and omized assignments as prespecified in the respective study protocol , patients were followed up longitudinally for a mean of 3 years for angina class , left ventricular ejection fraction , medication usage , and adverse events . Results No procedural mortality , myocardial infa rct ion , or cerebral embolism occurred . Pericardiocentesis was required in two patients ( 2.6 % ) . Card 
    Output:
    
Photobiomodulation in animal models showed consistently positive effects over a range of wavelengths and application parameters , with reductions in total infa rct size ( up to 76 % ) , decreases in inflammation and scarring , and increases in tissue repair .
Multiple molecular pathways were identified , including modulation of inflammatory cytokines , signalling molecules , transcription factors , enzymes and antioxidants .