Introduction: Photodynamic therapy is indicated for the treatment of superficial basal cell carcinoma, Bowen's disease and actinic keratosis. Reactive oxygen radicals are released from the metabolite of the topically applied photosensitizer that is excited by light, which selectively leads to the destruction of tumor cells. The procedure can be performed with an artificial light source or with the use of sunlight. The latter is called daylight photodynamic therapy, which is an effective and painless procedure. Objective: Our aim was to introduce daylight photodynamic therapy in actinic keratoses at our department and to optimize the treatment protocol for the local climatic conditions. Method: Three clinical trials were performed. The difference between the treatment protocols was between the incubation time of the photosensitizer on the skin and in the time patients spent under the sunlight. Results: When using the international treatment protocol, 73% of the actinic keratoses showed complete, while 27% partial remission. By reducing the proportion of time patients spent outdoor, complete remission was achieved in two-thirds and partial remission in one-third of the lesions. At doses above 100 J/cm(2), severe erythema was observed 24 hours after the treatment. To avoid this, we calculated the time to be spent outdoor by dosimetry. Partial remission was achieved in 15%, complete remission in 85% of the actinic keratoses with good tolerability. Discussion: The stepwise modification of the treatment protocol resulted in an effective and well-tolerated treatment in actinic keratoses under the local climatic conditions. Conclusion: The method has been successfully adapted in our clinic and is used in daily practice to treat actinic keratoses.

INTRODUCTION Photodynamic therapy is indicated for the treatment of superficial basal cell carcinoma, Bowen's disease and actinic keratosis. Reactive oxygen radicals are released from the metabolite of the topically applied photosensitizer that is excited by light, which selectively leads to the destruction of tumor cells. The procedure can be performed with an artificial light source or with the use of sunlight. The latter is called daylight photodynamic therapy, which is an effective and painless procedure. OBJECTIVE Our aim was to introduce daylight photodynamic therapy in actinic keratoses at our department and to optimize the treatment protocol for the local climatic conditions. METHOD Three clinical trials were performed. The difference between the treatment protocols was between the incubation time of the photosensitizer on the skin and in the time patients spent under the sunlight. RESULTS When using the international treatment protocol, 73% of the actinic keratoses showed complete, while 27% partial remission. By reducing the proportion of time patients spent outdoor, complete remission was achieved in two-thirds and partial remission in one-third of the lesions. At doses above 100 J/cm², severe erythema was observed 24 hours after the treatment. To avoid this, we calculated the time to be spent outdoor by dosimetry. Partial remission was achieved in 15%, complete remission in 85% of the actinic keratoses with good tolerability. DISCUSSION The stepwise modification of the treatment protocol resulted in an effective and well-tolerated treatment in actinic keratoses under the local climatic conditions. CONCLUSION The method has been successfully adapted in our clinic and is used in daily practice to treat actinic keratoses. Orv Hetil. 2022; 163(36): 1422-1429.

The therapeutic effect of ultraviolet (UV) light is generally attributed to its immunosuppressive and immunomodulatory effects. Since chronic inflammation is the major factor in the development of nasal polyposis, we have previously used mixed ultraviolet-visible light (mUV-VIS, Rhinolight®) phototherapy for the treatment of nasal polyps. In the present open, multicenter study, our aim was to delineate whether mUV-VIS applied postoperatively in vivo together with intranasal steroid treatment could reduce the recurrence of nasal polyps. After functional endoscopic sinus surgery, one group of patients received mUV-VIS light together with standard intranasal steroid (mometason furoate 2 × 200 μg) application for a 12-week treatment period, whereas the other patient group obtained only intranasal steroid for the same duration. We recorded nasal endoscopy images and obtained demographical and clinical data, total nasal score (TNS), and nasal obstruction symptom evaluation (NOSE). We performed acoustic rhinometry and measured nasal inspiratory peak flow. Follow-up was 12 months. We found that the recurrence of nasal polyps was significantly diminished, and based on video-endoscopic measurements, the size and grade of recurrent polyps were significantly smaller in the phototherapy-receiving group. Nasal obstruction values and NOSE were significantly better throughout the follow-up period in the mUV-VIS light-treated group than in the intranasal steroid monotreatment group. Rhinophototherapy together with standard nasal steroid application may have a supportive role in the treatment of recurrent bilateral nasal polyps.

Neonatal blue-light phototherapy induced a blistering reaction followed by eruption of melanocytic nevi on the exposed skin surface of a child with transient neonatal porphyrinemia. New nevi are still developing 4 years after the triggering event. The role of phototoxicity-induced epidermal injury, that of porphyrins and the influence of neonatal blue-light therapy, in this unique phenomenon are discussed.

Intranasal phototherapy has been found to be effective for the treatment of nasal polyposis (NP) therefore the aim was to investigate the apoptosis inducing effect of phototherapy in NP. In this ex vivo study nasal polyp tissue was surgically collected from 21 consecutive patients with chronic rhinosinusitis (CRS) associated with NP. The removed polyps were cut into pieces and tissue samples were irradiated in vitro by different doses of combined ultraviolet and visible light (UV/VIS: 280–650 nm) and by selective ultraviolet and visible light (sUV/VIS: 295–650 nm). Photodynamic therapy (PDT) was performed by presensitizing tissue samples with 5-delta-aminolevulinic acid (DALA) then irradiated with visible light (VIS: 395–650 nm). Tunel assay was applied to detect apoptosis of epithelial and inflammatory cells in irradiated and control nasal polyp tissue samples. UV/VIS light significantly increased epithelial cell and subepithelial leukocyte apoptosis compared to control groups. PDT treatment showed the highest surface epithelial cell as well as subepithelial leukocyte apoptosis compared to all other groups. Intranasal phototherapy may serve as a new potential therapeutical method in treatment of NP.

Az OTKA palyazatunk soran impulzuslezeres vekonyreteg epitessel jo minősegű wolfram, wolfram-nitrid, bor-karbid, gyemantszerű-szen, hidrogenezett amorf szen, szilicium karbid, amorf szilicium, teflon, biologiailag aktiv polihidroxi-butirat, pepszin es ureaz vekonyretegeket allitottunk elő. A retegek osszetetelet es szerkezetet meghatarozo lezeres plazmakeltes folyamatait in situ optikai meresekkel es főleg a retegek mikroszkopiai es spektroszkopiai vizsgalataval tanulmanyoztuk. Kiserleteinkkel megvizsgaltuk majd ertelmeztuk az ultrarovid es rovid lezerimpulzusok teljesitmenysűrűsegenek az ablaciora es a retegepitesre gyakorolt hatasat. Ertelmeztuk az inert es reaktiv gazban tortenő lezeres vekonyreteg epitest, es valtozatos osszetetelű illetve szerkezetű amorf, mikrokristalyos es nanoreszecskekből allo retegeket hoztunk letre. Preselt es fagyasztott celtargyakbol ultrarovid lezerimpulzusokkal es matrixszal elősegitett lezerdeszorpcios ionizacioval bioszenzorikai alkalmazasok celjara is alkalmas, biologiai funkciojukat megtarto retegeket hoztunk letre. | In the frame of the OTKA project we deposited good quality tungsten, tungsten-nitride, boron-carbide, diamond-like carbon, hydrogenated amorphous carbon, silicon carbide, amorphous silicon, Teflon, biologically active polyhydroxyl-butyrate, pepsin and urease thin films. We studied the processes of plasma formation that determine the composition and structure of the films with in-situ optical measurements and mainly with the microscopic and spectroscopic investigations of the deposited films. We investigated and interpreted the influence of the power density of short and ultra short laser pulses on the ablation and film formation. We explored the thin film deposition in inert and reactive atmospheres, and produced films of various compositions: amorphous, microcrystalline and nanostructured layers. We also deposited thin films with biological functionality suitable for biosensor purposes from pressed and frozen targets with ultrashort laser pulses and with matrix assisted laser desorption ionization.

We earlier reported that intranasal irradiation with the 308 nm xenon chloride (XeCl) ultraviolet-B laser and irradiation with a combination of ultraviolet-B (UVB), ultraviolet-A (UVA) and visible light (VIS) is highly effective in the treatment of allergic rhinitis and inhibit the immediate-type hypersensitivity reaction in the skin. Since photochemotherapy with 8-methoxypsoralen (8-MOP) plus UVA light (PUVA) is widely used in the treatment of different inflammatory skin disorders due to its immunosuppressive effect, in the present study we investigated the efficacy of intranasal PUVA treatment in allergic rhinitis and the effect of PUVA treatment on the skin prick test (SPT) reaction. An open study was performed in 17 patients with hay fever. Intranasal PUVA therapy was given four times weekly for 3 weeks. The treatment was started with a fluence of 0.5× of the individual minimal phototoxic dose (MPD) and the dosages were gradually increased. Evaluation was based on the symptom scores. The effect of PUVA treatment on the allergen-induced wheal formation was also studied in the SPT. PUVA treatment of the nasal cavity significantly decreased the nasal symptoms of the patients with allergic rhinitis. Treatment of the skin with PUVA also significantly suppressed the allergen-induced wheal formation in the SPT reaction. These data suggest that intranasal PUVA phototherapy is also an effective modality in the treatment of allergic rhinitis.

BACKGROUND:Narrow-band ultraviolet B phototherapy is an effictive and safe treatment for atopic dermatitis. We have previously found that the 308 nm xenon chloride excimer laser was more effective than the narrow-band ultraviolet B light for the treatment of psoriasis, suggesting that ultraviolet B laser might offer advantages over narrow-band ultraviolet B. OBJECTIVE:The purpose of this study was to evaluate the therapeutic efficacy of the 308 nm excimer laser in atopic dermatitis. PATIENTS AND METHODS:Fifteen patients with atopic dermatitis (less than 20% body area involvement) were treated with a xenon chloride excimer laser (XTRAC laser, Photomedex Inc.) twice weekly. The severity of the atopic dermatitis was assessed via (i) a clinical score characterizing the intensity of erythema, infiltration, lichenification and excoriation; (ii) the quality of life, determined by means of a questionnaire; and (iii) a visual linear analogue scale, with which the patients scored the severity of their pruritus. RESULTS:After 1 month of laser therapy, the clinical scores were significantly lower than the initial values. Similar decreases were observed for the quality of life and pruritus scores. No serious or unpleasant side-effects were observed. CONCLUSION:These results suggest that the xenon chloride excimer laser is an effective and well-tolerated treatment for localized atopic dermatitis.

Background: Phototherapy has a profound immunosuppressive effect and is able to inhibit hypersensibility reactions in the skin.Objective: We evaluated whether phototherapy using a combination of UV-B (5%), UV-A (25%), and visible light (70%), referred to as mUV/VIS, is effective in treating allergic rhinitis. Methods: We conducted a randomized, double-blind study, in 49 patients with hay fever. The study was performed during the ragweed season. Each intranasal cavity was illuminated 3 times a week for 3 weeks with mUV/VIS or with low-intensity visible light. Symptom scores, inflammatory cells, and their mediators were assessed in nasal lavages. In vitro effects of mUV/VIS irradiation on T-cell and eosinophil apoptosis and its inhibitory effect on mediator release from basophils were examined.Results: Rhinophototherapy was tolerated well and resulted in a significant improvement of clinical symptoms for sneezing (P < .016), rhinorrhea (P < .007), nasal itching (P < .014), and total nasal score (P < .004). None of the scores improved significantly in the control group. Scores for nasal obstruction slightly improved after mUV/VIS treatment and significantly increased in the control group (P < .017). In the nasal lavage, phototherapy significantly reduced the number of eosinophils and the level of eosinophil cationic protein and IL-5. In vitro irradiation of T cells and eosinophils with mUV/VIS light dose-dependently induced apoptosis. Furthermore, mUV/VIS irradiation inhibited the mediator release from RBL-2H3 basophils.Conclusion: These results suggest that phototherapy is an effective modality to treat allergic rhinitis and offer new options for the treatment of immune-mediated mucosal diseases.

Recently we found that ultraviolet B (UVB) irradiation in erythematous doses significantly inhibited the immediate type hypersensibility reaction in the skin. In the present study we investigated the effects of different wavelengths on the skin prick test reaction (SPT). The forearm of ragweed allergic patients was irradiated with increasing doses of ultraviolet A (UVA), visible light (VIS) or combined UVB, UVA and VIS light, referred to as mUV/VIS. SPTs were performed 24 h after irradiation both on irradiated and non-irradiated control skin areas using ragweed extract. UVA and VIS irradiation led to a slight, not significant inhibition of allergen-induced wheal formation. Mixed irradiation with mUV/VIS light resulted in a dose-dependent inhibition of the allergen-induced wheal formation. The inhibition was significant already at suberythematous doses. As there is a good correlation between SPT and the nasal symptoms in patients with hay fever these data suggest that phototherapy with mUV/VIS light might be an effective and safe treatment modality for immediate type hypersensibility reactions in the skin and nasal mucosa.

We earlier reported that the 308 nm xenon chloride (XeCl) ultraviolet B (UVB) laser is highly effective for the treatment of inflammatory skin diseases. Since UVB irradiation has been shown to exert both local and systemic immunosuppression, we investigated the clinical efficacy of UVB irradiation in allergic rhinitis. In an open study, groups of patients with severe allergic rhinitis received intranasal irradiation with a 308 nm XeCl UVB excimer laser for two weeks. In the low-dose group (n=10), treatment was given twice weekly, starting with 0.25 × the individual minimal erythema dose (MED), whereas patients in the medium-dose group (n=8) were treated four times weekly, starting with 0.4 × MED. In each group, the dosage was gradually increased. Evaluation was based on the symptom scores. The effect of the XeCl laser on the skin prick test reaction was also studied. In the low-dose group, seven patients completed the study, and there was no improvement in the nasal symptoms. In the medium-dose group, the XeCl UVB irradiation significantly inhibited the rhinorrhoea, the sneezing, the nasal obstruction and the total nasal score (p<0.05). The XeCl UVB excimer laser also inhibited the allergen-induced skin prick test in a dose-dependent manner. These results suggest that the XeCl UVB excimer laser might serve as a new therapeutic tool in the treatment of allergic rhinitis.

Recently we found that ultraviolet B (UVB) irradiation in erythematous doses significantly inhibited the immediate type hyper- sensibility reaction in the skin. In the present study we investigated the effects of different wavelengths on the skin prick test reaction (SPT). The forearm of ragweed allergic patients was irradiated with increasing doses of ultraviolet A (UVA), visible light (VIS) or combined UVB, UVA and VIS light, referred to as mUV/VIS. SPTs were performed 24 h after irradiation both on irradiated and non-irradiated control skin areas using ragweed extract. UVA and VIS irradiation led to a slight, not significant inhibition of aller- gen-induced wheal formation. Mixed irradiation with mUV/VIS light resulted in a dose-dependent inhibition of the allergen-induced wheal formation. The inhibition was significant already at suberythematous doses. As there is a good correlation between SPT and the nasal symptoms in patients with hay fever these data suggest that phototherapy with mUV/VIS light might be an effective and safe treatment modality for immediate type hypersensibility reactions in the skin and nasal mucosa. 2004 Elsevier B.V. All rights reserved.

Since ultraviolet-B (UVB) lht has been shown to exert both local and systemic immunosuppression, we investigated the clinical efficacy of UVB light in allergic rhinitis. In an open study, groups of patients with severe allergic rhinitis received intranasal irradiation with 308 nm xenon chloride (XeCl) UVB excimer laser for two weeks. In the low-dose group (n=7), treatment was given twice weekly, started with 0.25 × minimal erythema dose (MED), measured on the gluteal skin, whereas patients in the medium-dose group (n=8) were treated four times weekly starting with 0.4 × MED. In each group the light dosage was increased gradually. Evaluation was based on the symptom scores. The effect of XeCl laser on the skin prick test (SPT) reaction was also studied. In the low-dose group there was no improvement in the nasal symptoms. In the medium-dose group the XeCl UVB light significantly reduced rhinorrhoea, sneezing, nasal obstruction and total nasal score (p<0.05). The XeCl UVB excimer laser also inhibited the allergen induced skin prick reaction (SPT) in a dose dependent manner. XeCl UVB excimer laser might be a new therapeutic tool in the treatment of allergic rhinitis.

Experimental investigations and thermal calculations of laser induced backside wet etching (LIBWE) of fused silica are presented. Fused silica plates having 1 mm thickness were irradiated by an ArF excimer laser in the presence of liquid absorber. The absorbing liquids were naphthalene–methyl-methacrylate solutions with different concentrations (0, 0.21, 0.43, 0.85 and 1.71 mol/dm3). The absorption coefficients (α) of these solutions at the applied wavelength were determined using a plano–concave microcuvette. It was found that the value of α could be varied in the range of 39400–62300 cm−1 by the change of the naphthalene content. The dependence of the etch rate on both the absorption coefficient of the liquid absorbers and the applied fluence was studied. The etch depths were measured by an atomic force microscope. At 450 mJ/cm2 laser fluence, the etch rates were found to be between 13.3 and 22.2 nm/pulse depending on the actual absorption coefficient. In the next experiment the laser fluence was varied from 110 to 860 mJ/cm2 and the etch rate was found to vary between 4.7 and 49.5 nm/pulse when the concentration of the applied solution was constant 0.85 mol/dm3. The mechanism of the LIBWE can be explained in the first approximation by thermal effects and their consequences. We calculated the maximal depth of melted fused silica layer by numerical solution of the one-dimension heat flow equation taking into account the phase transformations of the liquid reagents and the fused silica target. These calculations proved that the thickness of the melted quartz layer depends linearly on both of the absorption coefficient of the liquid and the laser fluence. Our calculations give an upper estimation of the etch rate. On the basis of our results a possible interpretation of the LIBWE was suggested.

Allergic-type diseases are current nowadays, and they are frequently caused by certain metals. We demonstrated that the metal objects can be covered by Teflon protective thin layers using a pulsed laser deposition procedure. An ArF excimer laser beam was focused onto the surface of pressed PTFE powder pellets; the applied fluences were 7.5–7.7 J/cm2. Teflon films were deposited on fourteen-carat gold, silver and titanium plates. The number of ablating pulses was 10000. Post-annealing of the films was carried out in atmospheric air at oven temperatures between 320 and 500 °C. The thickness of the thin layers was around 5 μm. The prepared films were granular without heat treatment or after annealing at a temperature below 340 °C. At 360 °C a crystalline, contiguous, smooth, very compact and pinhole-free thin layer was produced; a melted and re-solidified morphology was observed above 420 °C. The adhesion strength between the Teflon films and the metal substrates was determined. This could exceed 1–4 MPa depending on the treatment temperature. It was proved that the prepared Teflon layers can be suitable for prevention of contact between the human body and allergen metals and so for avoidance of metal allergy.

The most known feature of polytetrafluoroethylene (PTFE) is its adhesion behavior: it is hydrophobic and oleophobic at the same time. This can cause serious problems and obstacles during the surface treatment and fixing of PTFE objects. During our experiments Teflon films were irradiated by an ArF excimer laser beam in presence of liquid photoreagents containing amine groups (aminoethanol, 1,2-diaminoethane, triethylenetetramine). In consequence of the treatment the adhesion of the modified surfaces significantly increased, the samples could be glued and moistened. The adhesion strength of the glued surfaces was measured in the function of the applied laser fluence. The adhesion strength increased drastically between 0-1 mJ/cm(2) and showed saturation above 1 mJ/cm(2) at approximately 5-9 MPa values depending on the applied photoreagents. On the basis of our experiments it was found that the treatment with triethylene-tetramine was the most effective. The surface chemical modifications of the treated Teflon samples can be due to the incorporation of amine groups into the surface layer.