Thermal-induced release of sulforhodamine dye from laser-irradiated diphosphatidylcholine liposomes occurs during a gel-liquid crystal phase transition process and has important ramifications for targeted photodynamic therapy protocols for the treatment of a variety of diseases.

Permanent infections recognized as oncogenic factor. STD is common concomitant diseases in early precancerous genital tract lesions. Simple optical detection of early regressive pre cancer in cervix is the aim of this study. Hereditary immunosupression most likely is risk factor for cervical cancer development. Light induced fluorescence point monitoring fitted to live cervical tissue diagnostics in 42 patients. Human papilloma virus DNR in cervix tested by means of Hybrid Capture II method. Ultraviolet (337 nm) laser excited fluorescence spectra in the live cervical tissue analyzed by Principal Component (PrC) regression method and spectra decomposition method. PCr method best discriminated pathology group "CIN I and inflammation"(AUC=75%) related to fluorescence emission in short wave region. Spectra decomposition method suggested a few possible fluorophores in a long wave region. Ultraviolet (398 nm) light excitation of live cervix proved sharp selective spectra intensity enhancement in region above 600nm for High-grade cervical lesion. Conclusion: PC analysis of UV (337 nm) light excitation fluorescence spectra gives opportunity to obtain local immunity and Low-grade cervical lesion related information. Addition of shorter and longer wavelengths is promising for multi wave LIF point monitoring method progress in cervical pre-cancer diagnostics and utility for cancer prevention especially in developing countries.

PDT is a treatment which uses a light-sensitive chemical, an appropriate wavelength light and tissue oxygen to achieve tumour necrosis. Its originates at the beginning of the 20" Century but in the last 10-15 years PD and PDT become real clinical practicalities. PDT has been shown to be an effective cancer treatment method in all common human cancers. In lung cancer its aims are palliation with survival benefit in advanced stage disease and curative intent in early stage tumours. At the Yorkshire Laser Centre (YLC), PD has been used for endoscopic diagnosis particularly lung cancer. PDT has been used in all major specialities particularly with lung and oesophageal cancer. The major work of the YLC has related to the prospective study of PDT in lung and oesophageal cancer. Our experience in lung cancer suggests indications for PD to be: diagnosis of early superficial cancer, to aid mapping of bronchoscopic extent of tumour allowing complete resection, monitoring treatment, and surveillance of operated patients. Our PDT results in lung cancer confirm: good palliation in advanced stage cancer with survival benefit in some subsets of patients, and long survival/cure of disease in early stage disease (>70% 5 year survival).

The Yorkshire Laser Centre has been engaged in Photodynamic Therapy (PDT) since 1990. In this article we present our experience highlighting the lesson learnt. 280 bronchoscopic PDT treatments have been carried out in 160 patients divided in 2 groups. Group A: (Nr 144) with advanced inoperable disease and Group E (Nr 16) with early stage cancer. PDT method was intravenous administration of 2mg/kg bw of Photofrin followed by bronchoscopic illumination of 630nm laser light. There was no procedure-related mortality. A total of 9 cases of photosensitivity (skin burn) occurred in the series (5.6% of patients). Every patient in both groups expressed their total satisfaction to treatment. Group A: Symptom relief was achieved in all. This was matched by improvement in significant bronchial opening (58.1%). Survival was 9.6 months (mean).This was greater in patients with better performance status and lower stage of disease. Group E: Every patient had a complete response to treatment. Survival in this group was 75.4 months (mean). We conclude that bronchoscopic PDT is indicated in both advanced and early stage lung cancer. In the former it provides symptomatic relief in all and survival benefit in some; in the latter it achieves long survival and potential cure.

Arginine, a semi-essential amino acid, and metabolites of arginine exert multiple biological effects. It has been known that arginine causes the release of various hormones such as insulin, glucagon, growth hormone, prolactin, and adrenal catecholamines. Arginine infusion also produces vasodilation, and in the kidney increased plasma flow accompanied by increases in glomerular filtration rate (GFR). Recent studies have showed that blue and red light irradiation in vitro and in vivo can increase production of nitric oxide (NO), superoxide anion, and related reactive oxygen species (ROS). These then can modulate the production and secretion of several cytokines and other mediators and play an important role as regulatory mediators in signaling processes which can then modulate the production, mobilization and homing of stem cells. It is proposed that some of the therapeutic effects of light can be considered to be due to the changes in the metabolism of L-arginine. The regulation of L-arginine turnover by the use of light at blue wavelengths between 400nm and 510nm can be the explanation for some of the observed effects of blue light: lowering of blood pressure, pain killing effect, regulating insulin production, anti-inflammatory action, and possible effects on the release and homing of stem cells.

Activation of angiogenesis under laser irradiation is one of the feasible explanations for long lasting treatment effects of laser therapy. The aim of the current study is the investigation of red low level laser light influence on angiogenesis study in vitro, and comparison with effects of vascular endothelial growth factor (VEGF) application. The study was done on rat thoracic aortal rings. Samples of group 1 served as control, group 2 samples were incubated with VEGF, group 3 samples were irradiated with low level laser (660 nm, 20 mW) during 10 min, and group 4 samples were incubated with VEGF and received 10 min of laser irradiation. Low level laser irradiation activates the process of angiogenesis. In the control group angiogenesis of new vessels was not detected. Laser irradiation promoted angiogenesis. The area covered by new vessels was 1,9±0,29 mm² and the maximal length of vessels was 0,75±0,lO mm. No statistical difference was discovered between laser irradiation and VEGF application. After combined influence of VEGF and laser light irradiation the area covered by new vessels was 6,98±0,88 mm² and the maximal length of vessels was 1,7±0,23 mm. So, laser irradiation can intensify effects of VEGF on angiogenesis.

The aim of this study was to assess the effects of low output laser therapy as an adjuvant treatment in grade 1 diabetic foot ulcers. Methods: Sixteen patients were randomly divided equally into two groups. Group A had daily dressing only, while group B had low output laser therapy instituted five days a week in addition to daily dressing. Serial measurement of the ulcer was done weekly using digital photography and analyzed. Results: The rate of healing in group A was 10.42 mm²/week, and in group B was 66.14mm²/week. The difference in the rate of healing was statistically significant, p<0.05. Conclusion: Laser therapy as an adjuvant treatment accelerates diabetic ulcer healing by six times in a six week period.

The long-term effects of low level laser therapy can involve mechanisms connected with activation of migration of stem cells towards damaged areas. Stromal cell-derived factor-1 alpha (SDF-1) plays a critical role in stem cell migration towards areas of tissue injury and hypoxia. This study examines the influence of laser light on migration of stem cells (FDCP-mix stem cell line) in absence and in presence of SDF-1, using Transwell system with 2 connected chambers separated by a filter. The first chamber contained medium and stem cells, second chamber contained medium with or without SDF. Group 1 cells served as a control. Cells of groups 2 and 5 were irradiated by red diode laser (660 nm, 20 mW, 15 min). Cells of groups 3 and 6 received infrared (IR) diode laser (958 nm, 36 mW, 15 min). Group 4 was SDF-1 control. Stem cells were seeded into first chamber of the Transwell system, and filters were placed into the wells containing medium with 150 ng/ml SDF-1 (groups 4,5,6) or without SDF-1 (groups 1,2,3). After incubation cells were collected and counted. The count of spontaneously migrated cells was 1496,5±409 (100%) in case of control. Red and IR laser light increased motility of stem cells up to 1892±283 (126%) and 2255,5±510 (151%) accordingly. Influence of SDF-1 caused directed migration of 3365,5±489 cells (225%). Combined effects of light irradiation and SDF-1 were significantly stronger (p<0,05): 5813±1199 (388%) for SDF-1 and red laser , 6391,5±540 (427%) for SDF-1 and IR laser. Study shows that laser radiation can up-regulate stem cell migration towards higher SDF-1 gradient.

Nd:YAP slab crystal in the form of triangle with the Brewster-angle-cut input faces was used as an active medium for diode-side-pumped laser. Optical pumping was accomplished by a quasi-CW diode ARR18P400 with peak power 400 W closely attached to the active crystal without any coupling optics. The maximum generated output energy in free-running multimode regime was 26 mJ and 17 mJ for wavelengths 1079.6 nm and 1341.6 nm, respectively. Corresponding maximal slope efficiency was 30% and 19%, respectively. The output radiation was horizontally polarized. With the insertion of the LiF:F₂^- saturable absorber in to the optimized resonator, the pulses with the peak power 30 kW (wavelength 1079.6 nm, length 70 ns FWHM, energy 2 mJ) were obtained at wavelength 1079.6 nm. This system is enough compact and power-full to be useful tools for medical application.

The aim of the work was to investigate the possibility of the ureter wall perforation by Er:YAG laser radiation and to explore the basic interaction characteristics for ureter surface and its deep structures. For these experiments Er:YAG laser system (wavelength 2.94 μm) working in free-running and Q-switched regime was utilized. Laser radiation was delivered to the investigated tissue by a special waveguide system. The basic part was a cyclic olefin polymer-coated silver hollow glass waveguide (inner/outer diameter 700/850 μm or 320/450 μm). Sealed cap of the waveguide was used for contact treatment. Maximum interaction pulse energy and length for free-running Er:YAG I laser with the 700μm waveguide were 100mJ and 200μs, respectively (corresponding intensity was 130 kW/cm²). Similarly the maximum interaction pulse energy and length for free-running Er:YAG II laser with the 320 μm waveguide were 80 mJ and 200 μs , respectively (corresponding intensity was 500 kW/cm²). Maximum interaction pulse energy and length in Q-switched regime were 17 mJ and 70 ns, respectively (corresponding intensity 63 MW/cm²). The number of pulses needed to perforate the ureter wall tissue (thickness ~1 mm) for using long 200 μs Er:YAG pulses (thermal ablation) and short 70 ns Er:YAG pulses (photoablation) was found. From the histological evaluation it follows that the application of Q-switched Er:YAG laser radiation on ureteral tissue resulted in minimum adjacent tissue alteration (up to 50μm from the surface) without any influence on the deeper layers.

This study aims to verify the effects of AsGa Laser in the scarring of tendon lesion in rats with low nourishment condition and to analyze the ideal light density by means of histopathologic findings highlighted by light microscopy. After the proposed nutritional condition was verified the animals were divided into 3 groups denominated as follows: GI control group, GII laser 1 J/sq.cm. and GIII laser 4 J/sq.cm. The lesions were induced by means of routine surgical process for tendon exposure: There was a crushing process with Allis pincers followed by saturated incision. The data obtained in relation to the amount of macrophage, leukocyte, fibroblast, vessel neoformation, fibrosis and collagen were submitted to parametric statistic procedures of variance analysis and "Tukey" Test and the result obtained was p < 0,05. According to the obtained results it can be concluded that low power laser therapy proved to be efficient in tendon repairing even though the animals suffered from malnutrition as well as the 1 J energy density proved to be more efficient in this case.

The authors present the results of recorded changes in the endothelium in rabbit's veins following photocoagulation by laser diode. In our study we concentrate mainly on the detailed description of individual changes in the rabbit's venous system in the area of the pelvis following laser therapy. The aim of our experiments was to reach the obliteration of rabbits' v. saphena lateralis using 980 nm laser diode with 200 micron fibre. The intensity of discharge was 3,5,6 and 7 watts. We examined the relationship between changes and the amount of joules that affect the endothelium of the rabbit's veins. The operation was conducted under general anaesthetic. All the animals survived treatment and were returned to breeders. Within the time span of one, three, six and eight weeks the laser treated veins were removed. They were fixated in formaldehyde and sent for microscopic examination. We were interested in how long it will take for fibrous changes to occur in the endothelium of the vein and thus also the subsequent occlusion of the vein depending on the amount of joules applied per one centimetre of the vein.

Optical spectroscopy in the ultraviolet, visible and mid-infrared spectral regions has been used to discriminate between healthy and diseased teeth of patients in the age range 15-75 years. Spectral scans of absorbance versus wavenumber and fluorescence intensity versus wavelength have been recorded and investigated for caries and periodontal disease. Such optical diagnostics can prove very useful in the early detection and treatment of tooth decay.

Technological advances in medicine are often directed towards the development of minimally invasive treatment modalities. The spatial selectivity of irradiation and the dose control are essential criteria's that influence the effectiveness of a laser treatment. We propose a new irradiation technique to improve the laser irradiation selectivity and dose control. The technique is based on the use of a spatial light modulator to project a'rectangular laser image of 8×5mm in our prototype. The spatial distribution of the irradiation is controlled in real time by image analysis to discriminate between the target area to be irradiated and the surrounding parts to be preserved. This technique is able to achieve a multi targets irradiation simultaneously. The resolution is about 12μm and is only limited by the camera resolution. Thanks to a collinear optical scheme, the calibration of the system is simple and robust. The duration of the control loop between image acquisition and laser treatment can be less than 200ms for the entire image (depending on the image analysis complexity).

In the field of neurosurgery for brain tumor, it is crucially important to remove almost totally certain brain tumors because of patients' quality of life. However, there has been few effective means of determining the boundaries between tumor tissue and surrounding normal brain parenchyma, making tumor resection totally dependent on the experiencing judgment of surgeons. Therefore, it is quite desirable to construct a real-time and highly sensitive monitoring system to detect tumor margins during surgery. In this study, proposed is the novel photo-dynamic diagnosis method for glioma-surgery. Using excited fluorescence from an oncotropic luminophore dye generally used in PDT and auto-fluorescence from some intracellular enzymes, e.g. NADH (Reduced Nicotinamide Adenine Dinucleotide), the ratio-metric technique in two-color laser-induced fluorescence was experimentally applied to brain tumor detection. The experiment was conducted using brain tumor rat models. An oncotoropic fluorescent dye, NPe6 (mono-L-aspartyl chlorin e6), was injected intravenously and then two fluorescence images were taken with irradiation of violet light, The fluorescence intensities of intracellular enzymes and NPe6 were found to decrease and increase in tumor lesions, respectively. Fluorescence intensity ratio could quantitatively identify tumor margins. Undesirable fluorescence variation could be reduced, which was dependent on inhomogeneous irradiation intensity distribution due to brain surface shape and illuminating light source itself. Thus, the ratio image could achieve higher contrast enhancement in tumor boundaries than single-color PDD. Furthermore, the histological examination provided correlation with ratio-image enhanced area. Consequently, the present method was clarified to be effective to brain tumor monitoring and quantitative tumor boundary demarcation.

It was proved that singulair does not cause macroscopical and histological alterations on the animals, but it is not known its influence on the molecular level. The purpose of our work is to explore teratogenic effects of singulair on the animals by using our non-standard method (which is preciser than standard method, because it showes not only macroscopical, but also and molecular alterations in the damage tissue), hoping, that it would be the help for the pregnant women to decide can they take this drug or not. We injected singulair (25 mg/kg of rat) to one group of pregnant rats in rareripe period (from the first to the eight day) of embryogenesis. Another group of pregnant rats got injections of teratogenic substance ochratoxin A (25 pg/kg of rat) in the same period of embryogenesis. The third group got injections of physiological solution. There were taken 10 rats to everyone group. In the end of rareripe period we took a blood sample from each rat of the rats and wrote a spectrum of everyone sample by using spectrophotometer. We got, that spectra of solutions from the first and the third group were very similar (there were no statistical difference) and spectra of solutions from the second group were very similar (there were no statistical difference), but statistical difference was between the first and the third group together and the second group in the zone of 200-350 nm. At the twentieth day of pregnancy we made Caesarean section to all of the rats, compared embryos interpendent and did not find any defects in anyone of them through all the first and the third group, but everyone embryo from the second group had a lot of defects.

We combined a non-linear microscope with a sensitive prism-based spectrograph and employed it for the imaging of the auto fluorescence of skin tissues. The system has a sub-micron spatial resolution and a spectral resolution of better than 5 nm. The spectral images contain signals arising from two-photon excited fluorescence (TPEF) of endogenous fluorophores in the skin and from second harmonic generation (SHG) produced by the collagen fibers, which have non-centrosymmetric structure. Non-linear microscopy has the potential to image deep into optically thick specimens because it uses near-infrared (NIR) laser excitation. In addition, the phototoxicity of the technique is comparatively low. Here, the technique is used for the spectral imaging of unstained skin tissue sections. We were able to image weak cellular autofluorescence as well as strong collagen SHG. The images were analyzed by spectral unmixing and the results exhibit a clear spectral signature for the different skin layers.

The enourmus boost from adopting biomolecular startegies associated to a better understanding of genetic phenomena opened the way to new methodologies. Among those we can surely locate dermoelectroporation, a methodology that uses the transdermal absorption capacity by means of an apparatus that delivers controlled electrical pulses able to open some "electrical doors". This methodology allows us a protocol of treatment suitable in subjects exhibiting the effects of acne, initial stages of skin ageing without tissue yield. and upkeep of aesthetic surgery. With the term "Biolifting" we signifie a treatment procedure aimed at rejuvenating the face by non-surgical, "soft" and out-patient treatment means. This treatment requires bi-monthly or monthly sessions, a total of four to eight, of a procedure consisting first in superficial microdermabrasion performed with corundum crystals, intended for the removal of the corneus layer and for vascularization. Immediately afterwards, active substances are introduced by means of the Dermoelectroporation treatment, characterized by the possibility of creating the opening of "intercellular gates" that allow the passage of the molecules. The session can be concluded with the application of pulsating light which introduces energy and stimulates the regenerating properties of connective tissues. A home treatment with moisturizing and regenerating creams ends the treatment which is used, with interesting results, also for the aesthetic therapy of stretch marks or hypertrophic scars.

The aim of this study was to compare the efficacy of three types of treatments in the periarthritis of the shoulder: corticosteroid injections, Low Level Laser Therapy (LLLT) or wait-and-see-policy. BACKGROUND DATA: Low level laser irradiation is a treatment method widely used in medical science. Many disorders, such as osteoarthritis and musculoskeletal conditions with pain, have been treated with LLLT. METHODS: Patients, suffering from periarthritis of the shoulder of at least 6 weeks' duration, were recruited by family doctors. We randomly allocated eligible patients to 6 weeks of treatment n. 20 (33%) with corticosteroid injection, n. 21 (35%) with LLLT and with wait-and-see policy n.19 (31%). We applied a number of 12 sessions with infrared Diode Laser Ga-As (904 nm), 60 W maximum power, peak power per pulse 27 W, pulse frequency 1280 Hz, average point region 2-8 J; dose/point = 3-4 J; total energy density 24 J/cm². Outcome measures included general improvement, severity of the main complaint, pain, shoulder disability, and patient satisfaction. Severity of shoulder complaints, abduction and elevation of the arm, and the pressure pain threshold were assessed. The principal analysis was done on an intention treatment basis. We assessed all outcomes at 3,6, 12, 26, 52 weeks. RESULTS: We randomly assigned 60 patients. At 6 weeks, corticosteroid injections were significantly better than all other therapy options for all outcome measures. Success rates were 90% (18) compared with 52% (11) for LLLT and 35% (7) for wait-and-see policy. Long-term differences between injections and LLLT were significantly in favour of LLLT. Success rate at 52 weeks were 14 (70%) for injections, 19 (90.5%) for LLLT, and 16 (84%) for wait-and-see policy. LLLT had better results than a wait-and-see policy, but differences were not significant ( p < 0.0001). CONCLUSIONS: Patients should be properly informed about the advantages and disadvantages of the treatment options for the periarthritis of the shoulder. The decision to treat with LLLT or to adopt a wait-and-see policy might depend on available resources, since the relative gain of LLLT is better, but also small at long-term.

Background: Presently, there is no unanimous consensus regarding the methods to introduce laser therapy, on a large scale, into a medical assistance system. These methods may vary from one country to another, depending on some factors. Although, there are some compulsory stages that must be reached. Purpose: This paper's purpose is to present the necessary stages, in our opinion, to successfully introduce laser therapy in hospitals and treatment rooms in our country. They include, among others: an information of the public at large, by brochures or other informative materials, on therapeutic lasers' action; the introducing in high level medicine schools of courses on the biological action of low-level lasers; laboratory studies on action mechanisms of low level laser radiation on live tissues; establishing the more objective methods of patients' assessment; obtaining approval from the Bioethics Committee for clinical studies on volunteers, according to current legislation. Materials and methods: There had been done a preliminary clinical study on volunteers (over 100 in number), using mainly subjective methods of evaluation. The patients have been also monitored also after the treatment, during one to six months. We present briefly a method of monitoring and objective assessment, by optical means, for laser therapy results, which we intend to use in the near future. Results:-There are presented the stages we reached till now. In the preliminary clinical study we have treated patients with various pathologies: skin diseases, dental, surgical and neuralgic pathology etc. We observed an amelioration or total remission on the most patients and also a good mood after the treatments. There are presented a few cases with significant results. Discussion and conclusion: We estimate the success rate of our treatments with over 60 percents. We hope this study shall be useful for the purpose mentioned in the paper's title. In a country where living standard is low, laser therapy may be a viable alternative to the methods of conservative medicine, characterized by large costs and with a series of shortcomings.

Purpose: To discuss present and future treatment possibilities in different types of choroidal neovascularisation. Methods: Presented are angiographic- and OCT-findings in patients with macular degeneration of different origin. Choroidal neovascularisations, which are not likely to respond positively to established procedures like thermal laser coagulation or photodynamic therapy will be discussed. Results and conclusions: Present study-guidelines and new methods of pharmacological intervention are analysed in different patterns of macular degeneration. Conventional laser coagulation in the treatment of classic, extrafoveal CNV and photodynamic therapy of predominantly classic subfoveal CNV still represent a gold standard. There are new recommendations, loosening the tight criteria of the TAP and VIP-guidelines, which cover, for instance, wider visual acuity ranges and the treatment of juxtafoveally located choroidal neovascularisations. Positive findings in literature confirm the role of PDT in pathologic myopia and other non-AMD CNV. Studies about surgical procedures, like macula- or RPE-translocation after surgical removal or thermal laser destruction of the CNV are in progress and are expected to show promising results. Phase II/III studies will soon point out the effect of anti-VEGF agents. The application of intravitreal (triamcinolone) or peribulbar (anecortave acetat) steroids could be useful. The combination with surgical or laser techniques could bring further benefit to the patient.

Oral squamous cell carcinoma (OSCC) has been shown to spread locally and infiltrate adjacent bone or via the lymphatic system to the cervical lymph nodes. This usually necessitates a surgical neck dissection and either a local or segmental resection for bone clearance. While histopathology remains the gold standard for tissue diagnosis, several new diagnostic techniques are being developed that rely on physical and biochemical changes that mirror or precede malignant changes within tissue. The aim of this study was to compare findings of Elastic Scattering Spectroscopy (ESS) with histopathology on formalin-fixed specimens of both neck lymph node dissections and de-calcified archival bone from patients with OSCC. We wished to see if this technique could be used as an adjunct or alternative to histopathology in defining cervical nodal involvement and if it could be used to identify bone resection margins positive for tumour. 130 lymph nodes were examined from 13 patients. The nodes were formalin-fixed, bivalved and examined by ESS. The intensity of the spectrum at 4 points was considered for comparison; at 360nm, 450nm, 630nm and 690nm. 341 spectra were taken from the mandibular specimens of 21 patients, of which 231 spectra were taken from histologically positive sites and the rest were normal. The nodes and bone specimens were then routinely processed with haematoxylin and eosin-stained sections, examined histopathologically, and the results compared. Using Linear Discriminant Analysis (LDA) as a statistical method, a sensitivity of 98% and a specificity of 68% was obtained for the neck nodes and a sensitivity of 87% and a specificity of 80% for the bone margins.