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1.
Appl Opt ; 62(7): B188-B194, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37132906

RESUMO

We have created high-precision, miniaturized, substrate-free filters, based on ion beam sputtering on a sacrificial substrate. The sacrificial layer is cost efficient and environmentally friendly and can be dissolved using only water. We demonstrate an improved performance compared to filters on thin polymer layers from the same coating run. With these filters, a single-element coarse wavelength division multiplexing transmitting device for telecommunication applications can be realized by inserting the filter between fiber ends.

2.
Appl Opt ; 62(12): 3112-3117, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37133158

RESUMO

Atomic layer deposition (ALD) has been proven as an excellent method for depositing high-quality optical coatings due to its outstanding film quality and precise process control. Unfortunately, batch ALD requires time-consuming purge steps, which leads to low deposition rates and highly time-intensive processes for complex multilayer coatings. Recently, rotary ALD has been proposed for optical applications. In this, to the best of our knowledge, novel concept, each process step takes place in a separate part of the reactor divided by pressure and nitrogen curtains. To be coated, substrates are rotated through these zones. During each rotation, an ALD cycle is completed, and the deposition rate depends primarily on the rotation speed. In this work, the performance of a novel rotary ALD coating tool for optical applications is investigated and characterized with S i O 2 and T a 2 O 5 layers. Low absorption levels of <3.1p p m and <6.0p p m are demonstrated at 1064 nm for around 186.2 nm thick single layers of T a 2 O 5 and 1032 nm S i O 2, respectively. Growth rates up to 0.18 nm/s on fused silica substrates were achieved. Furthermore, excellent non-uniformity is also demonstrated, with values reaching as low as ±0.53% and ±1.07% over an area of 135×60m m for T a 2 O 5 and S i O 2, respectively.

3.
Appl Opt ; 60(31): 9828-9836, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34807170

RESUMO

Optical networks can carry significantly higher data rates than their equivalent electrical systems. Because of their unique properties and constraints, optical networks have their own design rules. In this paper, an algorithm for the optimization of optical networks is presented. In addition, an optimized optical decimal-binary converter is flexographically manufactured and examined for its transmission properties. It is verified that optimization can minimize attenuation by several orders of magnitude, and points of high optical losses can also be predicted and adjusted.

4.
Artigo em Inglês | MEDLINE | ID: mdl-29977732

RESUMO

Infection of donor sites in split-thickness skin grafts is one of the complications of skin transplantation. Nutrition status and associated diseases play important roles in healing of donor sites. There are different ways used to treat infected donor sites. Water-filtered infrared-A (wIRA), as a special form of heat radiation with a high tissue penetration and a low thermal load to the skin surface, can improve the healing of acute and chronic wounds both by thermal and thermic as well as by non-thermal and non-thermic effects. Water-filtered infrared-A (wIRA) increases tissue temperature, tissue oxygen partial pressure and tissue perfusion. These three factors are decisive for a sufficient supply of tissue with energy and oxygen and consequently also for wound healing and infection defense. This was confirmed in a case with a late severe healing disturbance of the donor sites after skin transplantation.

5.
Appl Opt ; 56(31): 8607-8617, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29091671

RESUMO

Research for new production chains in the field of waveguide fabrication is a challenging task. Realizing a cost efficient manufacturing process allows integrating optical data communication in arbitrary structures, for example, the wing of an airplane or the body of a car. The production chain described in this paper contains the design, simulation, and fabrication process of printed polymer optical waveguides (POWs).

6.
Ger Med Sci ; 15: Doc11, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28794695

RESUMO

Case description: A patient with a Barrett oesophageal carcinoma and a resection of the oesophagus with gastric pull-up developed swallowing disorders 6 years and 2 months after the operation. Within 1 year and 7 months two recurrences of the tumor at the anastomosis were found and treated with combined chemoradiotherapy or chemotherapy respectively. 7 years and 9 months after the operation local tumor masses and destruction were present with no ability to orally drink or eat (full feeding by jejunal PEG tube): quality of life was poor, as saliva and mucus were very viscous (pulling filaments) and could not be swallowed and had to be spat out throughout the day and night resulting in short periods of sleep (awaking from the necessity to spit out). In total the situation was interpreted more as a problem related to a feeling of choking (with food or fluid) in the sense of a functional dysphagia rather than as a swallowing disorder from a structural stenosis. At that time acetylcysteine (2 times 200 mg per day, given via the PEG tube) and irradiation with water-filtered infrared-A (wIRA), a special form of heat radiation, of the ventral part of the neck and the thorax were added to the therapy. Within 1 day with acetylcysteine saliva and mucus became less viscous. Within 2 days with wIRA (one day with 4 to 5 hours with irradiation with wIRA at home) salivation decreased markedly and quality of life clearly improved: For the first time the patient slept without interruption and without the need for sleep-inducing medication. After 5 days with wIRA the patient could eat his first soft dumpling although drinking of fluids was still not possible. After 2½ weeks with wIRA the patient could eat his first minced schnitzel (escalope). Following the commencement of wIRA (with typically approximately 90-150 minutes irradiation with wIRA per day) the patient had 8 months with good quality of life with only small amounts of liquid saliva and mucus and without the necessity to spit out. During this period the patient was able to sleep during the night. Discussion: The main physiological effects of water-filtered infrared-A (wIRA) are: wIRA increases tissue temperature, tissue oxygen partial pressure and tissue perfusion markedly. The five main clinical effects of wIRA are: wIRA decreases pain, inflammation and exudation/hypersecretion, and promotes infection defense and regeneration, all in a cross-indication manner. Therefore there is a wide range of indications for wIRA. The effects of wIRA are based on both its thermal effects (relying on transfer of heat energy) and thermic effects (temperature-dependent effects, occurring together with temperature changes) as well as on non-thermal and temperature-independent effects like direct effects on cells, cell structures or cell substances. Conclusion: Besides in a variety of other indications for wIRA, in cases of swallowing disorders (functional dysphagia) and hypersalivation or hypersecretion of mucus the use of wIRA should be considered as part of the treatment regime for improving a patient's quality of life.


Assuntos
Transtornos de Deglutição/terapia , Raios Infravermelhos/uso terapêutico , Sialorreia/terapia , Esôfago de Barrett/complicações , Esôfago de Barrett/cirurgia , Filtração , Temperatura Alta , Humanos , Masculino , Pessoa de Meia-Idade , Água
7.
Ger Med Sci ; 14: Doc08, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27408610

RESUMO

BACKGROUND: Water-filtered infrared-A (wIRA) is a special form of heat radiation with high tissue penetration and a low thermal load to the skin surface. wIRA corresponds to the major part of the sun's heat radiation, which reaches the surface of the Earth in moderate climatic zones filtered by water and water vapour of the atmosphere. wIRA promotes healing of acute and chronic wounds both by thermal and thermic as well as by non-thermal and non-thermic cellular effects. METHODS: This publication includes a literature review with search in PubMed/Medline for "water-filtered infrared-A" and "wound"/"ulcus" or "wassergefiltertes Infrarot A" and "Wunde"/"Ulkus", respectively (publications in English and German), and additional analysis of study data. Seven prospective clinical studies (of these six randomized controlled trials (RCT), the largest study with n=400 patients) were identified and included. All randomized controlled clinical trials compare a combination of high standard care plus wIRA treatment vs. high standard care alone. The results below marked with "vs." present these comparisons. RESULTS: wIRA increases tissue temperature (+2.7°C at a tissue depth of 2 cm), tissue oxygen partial pressure (+32% at a tissue depth of 2 cm) and tissue perfusion (effect sizes within the wIRA group). wIRA promotes normal as well as disturbed wound healing by diminishing inflammation and exudation, by promotion of infection defense and regeneration, and by alleviation of pain (with respect to alleviation of pain, without any exception during 230 irradiations, 13.4 vs. 0.0 on a visual analogue scale (VAS 0-100), median difference between groups 13.8, 95% confidence interval (CI) 12.3/16.7, p<0.000001) with a substantially reduced need for analgesics (52-69% less in the three groups with wIRA compared to the three control groups in visceral surgery, p=0.000020 and 0.00037 and 0.0045, respectively; total of 6 vs. 14.5 analgesic tablets on 6 surveyed days (of weeks 1-6) in chronic venous stasis ulcers, median difference -8, 95% CI -10/-5, p=0.000002). Further effects are: Faster reduction of wound area (in severely burned children: 90% reduction of wound size after 9 vs. 13 days, after 9 days 89.2% vs. 49.5% reduction in wound area, median difference 39.5% wound area reduction, 95% CI 36.7%/42.2%, p=0.000011; complete wound closure of chronic venous stasis ulcers after 14 vs. 42 days, median difference -21 days, 95% CI -28/-10, p=0.000005). Better overall evaluation of wound healing (surgical wounds: 88.6 vs. 78.5 on a VAS 0-100, median difference 8.9, 95% CI 6.1/12.0, p<0.000001). Better overall evaluation of the effect of irradiation (79.0 vs. 46.8 on a VAS 0-100 with 50 as neutral point, median difference 27.9, 95% CI 19.8/34.6, p<0.000001). Higher tissue oxygen partial pressure during irradiation with wIRA (at a tissue depth of 2 cm 41.6 vs. 30.2 mmHg, median difference 11.9 mmHg, 95% CI 9.6/14.2 mmHg, p<0.000001). Higher tissue temperature during irradiation with wIRA (at a tissue depth of 2 cm 38.9 vs. 36.4°C, median difference 2.6°C, 95% CI 2.2/2.9°C, p<0.000001). Better cosmetic result (84.5 vs. 76.5 on a VAS 0-100, median difference 7.9, 95% CI 3.7/12.0, p=0.00027). Lower wound infection rate (single preoperative irradiation: 5.1% vs. 12.1% wound infections in total, difference -7.0%, 95% CI -12.8%/-1.3%, p=0.017, of these: late wound infections (postoperative days 9-30) 1.7% vs. 7.7%, difference -6.0%, 95% CI -10.3%/-1.7%, p=0.007). Shorter hospital stay (9 vs. 11 postoperative days, median difference -2 days, 95% CI -3/0 days, p=0.022). Most of the effects have been proven with an evidence level of 1a or 1b. CONCLUSION: Water-filtered infrared-A is a useful complement for the treatment of acute and chronic wounds.


Assuntos
Hipertermia Induzida/métodos , Raios Infravermelhos/uso terapêutico , Infecção da Ferida Cirúrgica/terapia , Ferida Cirúrgica/terapia , Úlcera Varicosa/terapia , Cicatrização , Doença Aguda , Queimaduras/terapia , Doença Crônica , Humanos , Úlcera da Perna/terapia , Oxigênio/metabolismo , Pressão Parcial , Água
8.
Mol Endocrinol ; 23(9): 1494-504, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19460859

RESUMO

We have previously shown that treatment with the thyroid hormone T(3) increases the voltage-gated Na(+)current density (Nav-D) in hippocampal neurons from postnatal rats, leading to accelerated action potential upstrokes and increased firing frequencies. Here we show that the Na(+) current regulation depends on the presence of glial cells, which secrete a heat-instable soluble factor upon stimulation with T(3). The effect of conditioned medium from T(3)-treated glial cells was mimicked by basic fibroblast growth factor (bFGF), known to be released from cerebellar glial cells after T(3) treatment. Neutralization assays of astrocyte-conditioned media with anti-bFGF antibody inhibited the regulation of the Nav-D by T(3). This suggests that the up-regulation of the neuronal sodium current density by T(3) is not a direct effect but involves bFGF release and satellite cells. Thus glial cells can modulate neuronal excitability via secretion of paracrinely acting factors.


Assuntos
Hipocampo/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismo , Sódio/metabolismo , Tri-Iodotironina/metabolismo , Regulação para Cima , Animais , Astrócitos/citologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Modelos Biológicos , Técnicas de Patch-Clamp , Ratos , Ratos Wistar , Canais de Sódio/metabolismo
9.
GMS Krankenhhyg Interdiszip ; 4(2): Doc12, 2009 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-20204090

RESUMO

Water-filtered infrared-A (wIRA), as a special form of heat radiation with a high tissue penetration and a low thermal load to the skin surface, can improve the healing of acute and chronic wounds both by thermal and thermic as well as by non-thermal and non-thermic effects. wIRA increases tissue temperature (+2.7 degrees C at a tissue depth of 2 cm), tissue oxygen partial pressure (+32% at a tissue depth of 2 cm) and tissue perfusion. These three factors are decisive for a sufficient supply of tissue with energy and oxygen and consequently also for wound healing and infection defense. wIRA can considerably alleviate pain (without any exception during 230 irradiations) with substantially less need for analgesics (52-69% less in the groups with wIRA compared to the control groups). It also diminishes exudation and inflammation and can show positive immunomodulatory effects. The overall evaluation of the effect of irradiation as well as the wound healing and the cosmetic result (assessed on visual analogue scales) were markedly better in the group with wIRA compared to the control group. wIRA can advance wound healing (median reduction of wound size of 90% in severely burned children already after 9 days in the group with wIRA compared to 13 days in the control group; on average 18 versus 42 days until complete wound closure in chronic venous stasis ulcers) or improve an impaired wound healing (reaching wound closure and normalization of the thermographic image in otherwise recalcitrant chronic venous stasis ulcers) both in acute and in chronic wounds including infected wounds. After major abdominal surgery there was a trend in favor of the wIRA group to a lower rate of total wound infections (7% versus 15%) including late infections following discharge from hospital (0% versus 8%) and a trend towards a shorter postoperative hospital stay (9 versus 11 days). Even the normal wound healing process can be improved. The mentioned effects have been proven in six prospective studies, with most of the effects having an evidence level of Ia/Ib.wIRA represents a valuable therapy option and can generally be recommended for use in the treatment of acute as well as of chronic wounds.

10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 78(4 Pt 1): 040802, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18999372

RESUMO

In this Rapid communication, we show, with colloidal probe atomic force microscopy(AFM) measurements, that the formation and subsequent disruption of polymer bridges between two solid surfaces is characterized by slow relaxation times. This is due to the retardation of polymer dynamics near a surface. For colloidal particles that are in constant (Brownian) motion kinetic aspects are key. To understand these effects, we develop a model of polymer bridging and bridge disruption that agrees quantitatively with our experiments.

11.
Ger Med Sci ; 6: Doc08, 2008 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-19675735

RESUMO

BACKGROUND: Water-filtered infrared-A (wIRA) irradiation has been shown to enhance penetration of clinically used topically applied substances in humans through investigation of functional effects of penetrated substances like vasoconstriction by cortisone. AIM OF THE STUDY: Investigation of the influence of wIRA irradiation on the dermatopharmacokinetics of topically applied substances by use of optical methods, especially to localize penetrating substances, in a prospective randomised controlled study in humans. METHODS: The penetration profiles of the hydrophilic dye fluorescein and the lipophilic dye curcumin in separate standard water-in-oil emulsions were determined on the inner forearm of test persons by tape stripping in combination with spectroscopic measurements. Additionally, the penetration was investigated in vivo by laser scanning microscopy. Transepidermal water loss, hydration of the epidermis, and surface temperature were determined. Three different procedures (modes A, B, C) were used in a randomised order on three separate days of investigation in each of 12 test persons. In mode A, the two dyes were applied on different skin areas without water-filtered infrared-A (wIRA) irradiation. In mode B, the skin surface was irradiated with wIRA over 30 min before application of the two dyes (Hydrosun radiator type 501, 10 mm water cuvette, orange filter OG590, water-filtered spectrum: 590-1400 nm with dominant amount of wIRA). In mode C, the two dyes were applied and immediately afterwards the skin was irradiated with wIRA over 30 min. In all modes, tape stripping started 30 min after application of the formulations. Main variable of interest was the ratio of the amount of the dye in the deeper (second) 10% of the stratum corneum to the amount of the dye in the upper 10% of the stratum corneum. RESULTS: The penetration profiles of the hydrophilic fluorescein showed in case of pretreatment or treatment with wIRA (modes B and C) an increased penetration depth compared to the non-irradiated skin (mode A): The ratio of the amount of the dye in the deeper (second) 10% of the stratum corneum to the amount of the dye in the upper 10% of the stratum corneum showed medians and interquartile ranges for mode A of 0.017 (0.007/0.050), for mode B of 0.084 (0.021/0.106), for mode C of 0.104 (0.069/0.192) (difference between modes: p=0.0112, significant; comparison mode A with mode C: p<0.01, significant). In contrast to fluorescein, the lipophilic curcumin showed no differences in the penetration kinetics, in reference to whether the skin was irradiated with wIRA or not. These effects were confirmed by laser scanning microscopy. Water-filtered infrared-A irradiation increased the hydration of the stratum corneum: transepidermal water loss rose from approximately 8.8 g m(-2) h(-1) before wIRA irradiation to 14.2 g m(-2) h(-1) after wIRA irradiation and skin hydration rose from 67 to 87 relative units. Skin surface temperature increased from 32.8 degrees C before wIRA to 36.4 degrees C after wIRA irradiation. DISCUSSION: The better penetration of the hydrophilic dye fluorescein after or during skin irradiation (modes B and C) can be explained by increased hydration of the stratum corneum by irradiation with wIRA. CONCLUSIONS: As most topically applied substances for the treatment of patients are mainly hydrophilic, wIRA can be used to improve the penetration of substances before or after application of substances - in the first case even of thermolabile substances - with a broad clinical relevance as a contact free alternative to an occlusive dressing.

12.
Ger Med Sci ; 6: Doc11, 2008 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-19675738

RESUMO

BACKGROUND: Water-filtered infrared-A (wIRA) is a special form of heat radiation with a high tissue-penetration and with a low thermal burden to the surface of the skin. wIRA is able to improve essential and energetically meaningful factors of wound healing by thermal and non-thermal effects. AIM OF THE STUDY: prospective study (primarily planned randomised, controlled, blinded, de facto with one exception only one cohort possible) using wIRA in the treatment of patients with recalcitrant chronic venous stasis ulcers of the lower legs with thermographic follow-up. METHODS: 10 patients (5 males, 5 females, median age 62 years) with 11 recalcitrant chronic venous stasis ulcers of the lower legs were treated with water-filtered infrared-A and visible light irradiation (wIRA(+VIS), Hydrosun radiator type 501, 10 mm water cuvette, water-filtered spectrum 550-1400 nm) or visible light irradiation (VIS; only possible in one patient). The uncovered wounds of the patients were irradiated two to five times per week for 30 minutes at a standard distance of 25 cm (approximately 140 mW/cm(2) wIRA and approximately 45 mW/cm(2) VIS). Treatment continued for a period of up to 2 months (typically until closure or nearly closure of the ulcer). The main variable of interest was "percent change of ulcer size over time" including complete wound closure. Additional variables of interest were thermographic image analysis, patient's feeling of pain in the wound, amount of pain medication, assessment of the effect of the irradiation (by patient and by clinical investigator), assessment of feeling of the wound area (by patient), assessment of wound healing (by clinical investigator) and assessment of the cosmetic state (by patient and by clinical investigator). For these assessments visual analogue scales (VAS) were used. RESULTS: The study showed a complete or nearly complete healing of lower leg ulcers in 7 patients and a clear reduction of ulcer size in another 2 of 10 patients, a clear reduction of pain and pain medication consumption (e.g. from 15 to 0 pain tablets per day), and a normalization of the thermographic image (before the beginning of the therapy typically hyperthermic rim of the ulcer with relative hypothermic ulcer base, up to 4.5 degrees C temperature difference). In one patient the therapy of an ulcer of one leg was performed with the fully active radiator (wIRA(+VIS)), while the therapy of an ulcer of the other leg was made with a control group radiator (only VIS without wIRA), showing a clear difference in favour of the wIRA treatment. All mentioned VAS ratings improved remarkably during the period of irradiation treatment, representing an increased quality of life. Failures of complete or nearly complete wound healing were seen only in patients with arterial insufficiency, in smokers or in patients who did not have venous compression garment therapy. DISCUSSION AND CONCLUSIONS: wIRA can alleviate pain considerably (with an impressive decrease of the consumption of analgesics) and accelerate wound healing or improve a stagnating wound healing process and diminish an elevated wound exudation and inflammation both in acute and in chronic wounds (in this study shown in chronic venous stasis ulcers of the lower legs) and in problem wounds including infected wounds. In chronic recalcitrant wounds complete healing is achieved, which was not reached before. Other studies have shown that even without a disturbance of wound healing an acute wound healing process can be improved (e.g. reduced pain) by wIRA. wIRA is a contact-free, easily used and pleasantly felt procedure without consumption of material with a good penetration effect, which is similar to solar heat radiation on the surface of the earth in moderate climatic zones. Wound healing and infection defence (e.g. granulocyte function including antibacterial oxygen radical formation of the granulocytes) are critically dependent on a sufficient energy supply (and on sufficient oxygen). The good clinical effect of wIRA on wounds and also on problem wounds and wound infections can be explained by the improvement of both the energy supply and the oxygen supply (e.g. for the granulocyte function). wIRA causes as a thermal effect in the tissue an improvement in three decisive factors: tissue oxygen partial pressure, tissue temperature and tissue blood flow. Besides this non-thermal effects of infrared-A by direct stimulation of cells and cellular structures with reactions of the cells have also been described. It is concluded that wIRA can be used to improve wound healing, to reduce pain, exudation, and inflammation and to increase quality of life.

13.
GMS Krankenhhyg Interdiszip ; 2(2): Doc52, 2008 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-20204086

RESUMO

The central portion of chronic wounds is often hypoxic and relatively hypothermic, representing a deficient energy supply of the tissue, which impedes wound healing or even makes it impossible. Water-filtered infrared-A (wIRA) is a special form of heat radiation with a high tissue penetration and a low thermal load to the skin surface. wIRA produces a therapeutically usable field of heat and increases temperature, oxygen partial pressure and perfusion of the tissue. These three factors are decisive for a sufficient tissue supply with energy and oxygen and consequently as well for wound healing, especially in chronic wounds, and infection defense. wIRA acts both by thermal and thermic as well as by non-thermal and non-thermic effects. wIRA can advance wound healing or improve an impaired wound healing process and can especially enable wound healing in non-healing chronic wounds. wIRA can considerably alleviate the pain and diminish wound exudation and inflammation and can show positive immunomodulatory effects.In a prospective, randomized, controlled study of 40 patients with chronic venous stasis ulcers of the lower legs irradiation with wIRA and visible light (VIS) accelerated the wound healing process (on average 18 vs. 42 days until complete wound closure, residual ulcer area after 42 days 0.4 cm(2) vs. 2.8 cm(2)) and led to a reduction of the required dose of pain medication in comparison to the control group of patients treated with the same standard care (wound cleansing, wound dressing with antibacterial gauze, and compression garment therapy) without the concomitant irradiation. Another prospective study of 10 patients with non-healing chronic venous stasis ulcers of the lower legs included extensive thermographic investigation. Therapy with wIRA(+VIS) resulted in a complete or almost complete wound healing in 7 patients and a marked reduction of the ulcer size in another 2 of the 10 patients, a clear reduction of pain and required dose of pain medication, and a normalization of the thermographic image. In a current prospective, randomized, controlled, blinded study patients with non-healing chronic venous stasis ulcers of the lower legs are treated with compression garment therapy, wound cleansing, wound dressings and 30 minutes irradiation five times per week over 9 weeks. A preliminary analysis of the first 23 patients of this study has shown in the group with wIRA(+VIS) compared to a control group with VIS an advanced wound healing, an improved granulation and in the later phase of treatment a decrease of the bacterial burden. Some case reports have demonstrated that wIRA can also be used for mixed arterial-venous ulcers or arterial ulcers, if irradiation intensity is chosen appropriately low and if irradiation is monitored carefully. wIRA can be used concerning decubital ulcers both in a preventive and in a therapeutic indication. wIRA can improve the resorption of topically applied substances also on wounds. An irradiation with VIS and wIRA presumably acts with endogenous protoporphyrin IX (or protoporphyrin IX of bacteria) virtually similar as a mild photodynamic therapy (endogenous PDT-like effect). This could lead to improved cell regeneration and wound healing and to antibacterial effects. In conclusion, these results indicate that wIRA generally should be considered for the treatment of chronic wounds.

14.
Ger Med Sci ; 5: Doc08, 2007 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-19675716

RESUMO

BACKGROUND: Excessive exposure to solar ultraviolet radiation is involved in the complex biologic process of cutaneous aging. Wavelengths in the ultraviolet-A and -B range (UV-A and UV-B) have been shown to be responsible for the induction of proteases, e. g. the collagenase matrix metalloproteinase 1 (MMP-1), which are related to cell aging. As devices emitting longer wavelengths are widely used in therapeutic and cosmetic interventions and as the induction of MMP-1 by water-filtered infrared-A (wIRA) had been discussed, it was of interest to assess effects of wIRA on the cellular and molecular level known to be possibly involved in cutaneous degeneration. OBJECTIVES: Investigation of the biological implications of widely used water-filtered infrared-A (wIRA) radiators for clinical use on human skin fibroblasts assessed by MMP-1 gene expression (MMP-1 messenger ribonucleic acid (mRNA) expression). METHODS: Human skin fibroblasts were irradiated with approximately 88% wIRA (780-1400 nm) and 12% red light (RL, 665-780 nm) with 380 mW/cm(2) wIRA(+RL) (333 mW/cm(2) wIRA) on the one hand and for comparison with UV-A (330-400 nm, mainly UV-A1) and a small amount of blue light (BL, 400-450 nm) with 28 mW/cm(2) UV-A(+BL) on the other hand. Survival curves were established by colony forming ability after single exposures between 15 minutes and 8 hours to wIRA(+RL) (340-10880 J/cm(2) wIRA(+RL), 300-9600 J/cm(2) wIRA) or 15-45 minutes to UV-A(+BL) (25-75 J/cm(2) UV-A(+BL)). Both conventional Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) and quantitative real-time RT-PCR techniques were used to determine the induction of MMP-1 mRNA at two physiologic temperatures for skin fibroblasts (30 degrees C and 37 degrees C) in single exposure regimens (15-60 minutes wIRA(+RL), 340-1360 J/cm(2) wIRA(+RL), 300-1200 J/cm(2) wIRA; 30 minutes UV-A(+BL), 50 J/cm(2) UV-A(+BL)) and in addition at 30 degrees C in a repeated exposure protocol (up to 10 times 15 minutes wIRA(+RL) with 340 J/cm(2) wIRA(+RL), 300 J/cm(2) wIRA at each time). RESULTS: Single exposure of cultured human dermal fibroblasts to UV-A(+BL) radiation yielded a very high increase in MMP-1 mRNA expression (11 +/-1 fold expression for RT-PCR and 76 +/-2 fold expression for real-time RT-PCR both at 30 degrees C, 75 +/-1 fold expression for real-time RT-PCR at 37 degrees C) and a dose-dependent decrease in cell survival. In contrast, wIRA(+RL) did not produce cell death and did not induce a systematic increase in MMP-1 mRNA expression (less than twofold expression, within the laboratory range of fluctuation) detectable with the sensitive methods applied. Additionally, repeated exposure of human skin fibroblasts to wIRA(+RL) did not induce MMP-1 mRNA expression systematically (less than twofold expression by up to 10 consecutive wIRA(+RL) exposures and analysis with real-time RT-PCR). CONCLUSIONS: wIRA(+RL) even at the investigated disproportionally high irradiances does not induce cell death or a systematic increase of MMP-1 mRNA expression, both of which can be easily induced by UV-A radiation. Furthermore, these results support previous findings of in vivo investigations on collagenase induction by UV-A but not wIRA and show that infrared-A with appropriate irradiances does not seem to be involved in MMP-1 mediated photoaging of the skin. As suggested by previously published studies wIRA could even be implicated in a protective manner.

15.
GMS Krankenhhyg Interdiszip ; 2(2): Doc53, 2007 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-20204084

RESUMO

Water-filtered infrared-A (wIRA) as a special form of heat radiation with a high tissue penetration and with a low thermal load to the skin surface acts both by thermal and thermic as well as by non-thermal and non-thermic effects. wIRA produces a therapeutically usable field of heat in the tissue and increases tissue temperature, tissue oxygen partial pressure, and tissue perfusion. These three factors are decisive for a sufficient tissue supply with energy and oxygen and consequently as well for wound healing and infection defense. wIRA can considerably alleviate the pain (with remarkably less need for analgesics) and diminish an elevated wound exudation and inflammation and can show positive immunomodulatory effects. wIRA can advance wound healing or improve an impaired wound healing both in acute and in chronic wounds including infected wounds. Even the normal wound healing process can be improved.A prospective, randomized, controlled, double-blind study with 111 patients after major abdominal surgery at the University Hospital Heidelberg, Germany, showed with 20 minutes irradiation twice a day (starting on the second postoperative day) in the group with wIRA and visible light VIS (wIRA(+VIS), approximately 75% wIRA, 25% VIS) compared to a control group with only VIS a significant and relevant pain reduction combined with a markedly decreased required dose of analgesics: during 230 single irradiations with wIRA(+VIS) the pain decreased without any exception (median of decrease of pain on postoperative days 2-6 was 13.4 on a 100 mm visual analog scale VAS 0-100), while pain remained unchanged in the control group (p<0.001). The required dose of analgesics was 57-70% lower in the subgroups with wIRA(+VIS) compared to the control subgroups with only VIS (median 598 versus 1398 ml ropivacaine, p<0.001, for peridural catheter analgesia; 31 versus 102 mg piritramide, p=0.001, for patient-controlled analgesia; 3.4 versus 10.2 g metamizole, p=0.005, for intravenous and oral analgesia). During irradiation with wIRA(+VIS) the subcutaneous oxygen partial pressure rose markedly by approximately 30% and the subcutaneous temperature by approximately 2.7 degrees C (both in a tissue depth of 2 cm), whereas both remained unchanged in the control group: after irradiation the median of the subcutaneous oxygen partial pressure was 41.6 (with wIRA) versus 30.2 mm Hg in the control group (p<0.001), the median of the subcutaneous temperature was 38.9 versus 36.4 degrees C (p<0.001). The overall evaluation of the effect of irradiation, including wound healing, pain and cosmesis, assessed on a VAS (0-100 with 50 as indifferent point of no effect) by the surgeon (median 79.0 versus 46.8, p<0.001) or the patient (79.0 versus 50.2, p<0.001) was markedly better in the group with wIRA compared to the control group. This was also true for single aspects: Wound healing assessed on a VAS by the surgeon (median 88.6 versus 78.5, p<0.001) or the patient (median 85.8 versus 81.0, p=0.040, trend) and cosmetic result assessed on a VAS by the surgeon (median 84.5 versus 76.5, p<0.001) or the patient (median 86.7 versus 73.6, p=0.001). In addition there was a trend in favor of the wIRA group to a lower rate of total wound infections (3 of 46, approximately 7%, versus 7 of 48, approximately 15%, p=0.208) including late infections after discharge, caused by the different rate of late infections after discharge: 0 of 46 in the wIRA group and 4 of 48 in the control group. And there was a trend towards a shorter postoperative hospital stay: 9 days in the wIRA group versus 11 days in the control group (p=0.037). The principal finding of this study was that postoperative irradiation with wIRA can improve even a normal wound healing process.A prospective, randomized, controlled, double-blind study with 45 severely burned children at the Children's Hospital Park Schönfeld, Kassel, Germany, showed with 30 minutes irradiation once a day (starting on the first day, day of burn as day 1) in the group with wIRA and visible light VIS (wIRA(+VIS), approximately 75% wIRA, 25% VIS) compared to a control group with only VIS a markedly faster reduction of wound size. On the fifth day (after 4 days with irradiation) decision was taken, whether surgical debridement of necrotic tissue was necessary because of deeper (second degree, type b) burns (11 of 21 in the group with wIRA, 14 of 24 in the control group) or non-surgical treatment was possible (second degree, type a, burns). The patients treated conservatively were kept within the study and irradiated till complete reepithelialization. The patients in the group with wIRA showed a markedly faster reduction of wound area: a median reduction of wound size of 50% was reached already after 7 days compared to 9 days in the control group, a median reduction of wound size of 90% was already achieved after 9 days compared to 13 days in the control group. In addition the group with wIRA showed superior results till 3 months after the burn in terms of the overall surgical assessment of the wound, cosmesis, and assessment of effects of irradiation compared to the control group. In a prospective, randomized, controlled study with 12 volunteers at the University Medical Center Charité, Berlin, Germany, within each volunteer 4 experimental superficial wounds (5 mm diameter) as an acute wound model were generated by suction cup technique, removing the roof of the blister with a scalpel and a sterile forceps (day 1). 4 different treatments were used and investigated during 10 days: no therapy, only wIRA(+VIS) (approximately 75% wIRA, 25% VIS; 30 minutes irradiation once a day), only dexpanthenol (= D-panthenol) cream once a day, wIRA(+VIS) and dexpanthenol cream once a day. Healing of the small experimental wounds was from a clinical point of view excellent with all 4 treatments. Therefore there were only small differences between the treatments with slight advantages of the combination wIRA(+VIS) and dexpanthenol cream and of dexpanthenol cream alone concerning relative change of wound size and assessment of feeling of the wound area. However laser scanning microscopy with a scoring system revealed differences between the 4 treatments concerning the formation of the stratum corneum (from first layer of corneocytes to full formation) especially on the days 5-7: fastest formation of the stratum corneum was seen in wounds treated with wIRA(+VIS) and dexpanthenol cream, second was wIRA(+VIS) alone, third dexpanthenol cream alone and last were untreated wounds. Bacterial counts of the wounds (taken every 2 days) showed, that wIRA(+VIS) and the combination of wIRA(+VIS) with dexpanthenol cream were able to inhibit the colonisation with physiological skin flora up to day 5 when compared with the two other groups (untreated group and group with dexpanthenol cream alone). At any investigated time, the amount of colonisation under therapy with wIRA(+VIS) alone was lower (interpreted as more suppressed) compared with the group with wIRA(+VIS) and dexpanthenol cream. During rehabilitation after hip and knee endoprosthetic operations the resorption of wound seromas and wound hematomas was both clinically and sonographically faster and pain was reduced by irradiation with wIRA(+VIS). wIRA can be used successfully for persistent postoperative pain e.g. after thoracotomy.As perspectives for wIRA it seems clinically prudent to use wIRA both pre- and postoperatively, e.g. in abdominal and thoracic operations. wIRA can be used preoperatively (e.g. during 1-2 weeks) to precondition donor and recipient sites of skin flaps, transplants or partial-thickness skin grafts, and postoperatively to improve wound healing and to decrease pain, inflammation and infections at all mentioned sites. wIRA can be used to support routine pre- or intraoperative antibiotic administration or it might even be discussed to replace this under certain conditions by wIRA.

16.
GMS Krankenhhyg Interdiszip ; 2(2): Doc54, 2007 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-20204085

RESUMO

The experience of the pleasant heat of the sun in moderate climatic zones arises from the filtering of the heat radiation of the sun by water vapor in the atmosphere of the earth. The filter effect of water decreases those parts of infrared radiation (most parts of infrared-B and -C and the absorption bands of water within infrared-A), which would cause - by reacting with water molecules in the skin - only an undesired thermal load to the surface of the skin. Technically water-filtered infrared-A (wIRA) is produced in special radiators, whose full spectrum of radiation of a halogen bulb is passed through a cuvette, containing water, which absorbs or decreases the described undesired wavelengths of the infrared radiation. Within infrared the remaining wIRA (within 780-1400 nm) mainly consists of radiation with good penetration properties into tissue and therefore allows - compared to unfiltered heat radiation - a multiple energy transfer into tissue without irritating the skin, similar to the sun's heat radiation in moderate climatic zones. Typical wIRA radiators emit no ultraviolet (UV) radiation and nearly no infrared-B and -C radiation and the amount of infrared-A radiation in relation to the amount of visible light (380-780 nm) is emphasized. Water-filtered infrared-A as a special form of heat radiation with a high tissue penetration and with a low thermal load to the skin surface acts both by thermal (related to heat energy transfer) and thermic (temperature depending, with a relevant change of temperature) as well as by non-thermal (without a relevant transfer of heat energy) and non-thermic (not depending on temperature, without a relevant change of temperature) effects. wIRA produces a therapeutically usable field of heat in the tissue and increases tissue temperature, tissue oxygen partial pressure, and tissue perfusion. These three factors are vital for a sufficient tissue supply with energy and oxygen. As wound healing and infection defense (e.g. granulocyte function including their antibacterial oxygen radical formation) depend decisively on a sufficient supply with energy and oxygen, one explanation for the good clinical effect of wIRA on wounds and wound infections can be the improvement of both the energy supply per time (increase of metabolic rate) and the oxygen supply. In addition wIRA has non-thermal and non-thermic effects, which are based on putting direct stimuli on cells and cellular structures.wIRA can considerably alleviate the pain (with remarkably less need for analgesics) and diminish an elevated wound exudation and inflammation and can show positive immunomodulatory effects. wIRA can advance wound healing or improve an impaired wound healing both in acute and in chronic wounds including infected wounds. Even the normal wound healing process can be improved.wIRA is contact-free, easily applied, without discomfort to the patient, with absent consumption of material and with a good effect in the depth. The irradiation of the typically uncovered wound is carried out with a wIRA radiator.

17.
Ger Med Sci ; 4: Doc05, 2006 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-19675696

RESUMO

AIM OF THE STUDY: Investigation, whether water-filtered infrared-A (wIRA) irradiation during moderate bicycle ergometer endurance exercise has effects especially on local fat reduction and on weight reduction beyond the effects of ergometer exercise alone. METHODS: Randomised controlled study with 40 obese females (BMI 30-40 (median: 34.5), body weight 76-125 (median: 94.9) kg, age 20-40 (median: 35.5) years, isocaloric nutrition), 20 in the wIRA group and 20 in the control group. In both groups each participant performed 3 times per week over 4 weeks for 45 minutes bicycle ergometer endurance exercise with a constant load according to a lactate level of 2 mmol/l (aerobic endurance load, as determined before the intervention period). In the wIRA group in addition large parts of the body (including waist, hip, and thighs) were irradiated during all ergometries of the intervention period with visible light and a predominant part of water-filtered infrared-A (wIRA), using the irradiation unit "Hydrosun 6000" with 10 wIRA radiators (Hydrosun Medizintechnik, Müllheim, Germany, radiator type 500, 4 mm water cuvette, yellow filter, water-filtered spectrum 500-1400 nm) around a speed independent bicycle ergometer. MAIN VARIABLE OF INTEREST: change of "the sum of circumferences of waist, hip, and both thighs of each patient" over the intervention period (4 weeks). Additional variables of interest: body weight, body mass index BMI, body fat percentage, fat mass, fat-free mass, water mass (analysis of body composition by tetrapolar bioimpedance analysis), assessment of an arteriosclerotic risk profile by blood investigation of variables of lipid metabolism (cholesterol, triglycerides, high density lipoproteins HDL, low density lipoproteins LDL, apolipoprotein A1, apolipoprotein B), clinical chemistry (fasting glucose, alanin-aminotransferase ALT (= glutamyl pyruvic transaminase GPT), gamma-glutamyl-transferase GGT, creatinine, albumin), endocrinology (leptin, adiponectin (= adipo Q), homocysteine, insulin). All variables were at least measured before and after the intervention period. Ergometry (ECG, blood pressure behaviour, lactate curve with power at 2, 3 and 4 mmol/l) before the intervention period. In addition: nutrition training ahead of and during the intervention period with a nutrition protocol over one week for assessment of the daily energy intake; calculation of basic metabolic rate and total energy requirement. Assessment of undesired effects. Only methods of non-parametric statistics were used, both descriptive (median, percentiles of 25 and 75 (= interquartile range), minimum, maximum) and confirmatory (two-sided Mann-Whitney U test for unpaired samples for the only one main variable of interest). Total error probability: .05 (5%). An intention to treat analysis ITT with last observed carry forward method was used preferably (presented results) and in addition an on treatment analysis OT. Only 2 (treatment group) and 4 (control group) drop-outs occurred (mostly due to lack of time). RESULTS: The "sum of circumferences of waist, hip, and both thighs of each patient" decreased during the 4 weeks significantly more (p<.001) in the wIRA group than in the control group: medians and interquartile ranges: -8.0 cm (-10.5 cm/-4.1 cm) vs. -1.8 cm (-4.4 cm/0.0 cm). As well "body weight of each patient" decreased during the 4 weeks markedly more in the wIRA group than in the control group: medians and interquartile ranges: -1.9 kg (-4.0 kg/0.0 kg) vs. 0.0 kg (-1.5 kg/+0.4 kg); median of body weight changed from 99.3 kg to 95.6 kg (wIRA) vs. 89.9 kg to 89.6 kg (control). A similar effect showed the body mass index BMI. Blood variables of interest remained unchanged or showed some slight improvements during the treatment period, concerning most variables with no obvious differences between the two groups; insulin showed a slight trend to decrease in the wIRA group and to increase in the control group. Undesired effects of the treatment were not seen. DISCUSSION: The results of the study suggest, that wIRA - during moderate bicycle ergometer endurance exercise as lipolytic stimulus - increases local lipolysis with a local fat reduction (thighs) in the otherwise bradytrophic fatty tissue. The presumably underlying mechanisms of wIRA have already been proven: wIRA acts both by thermal effects and by non-thermal effects. Thermal effects of wIRA are the generation of a therapeutic field of warmth with the increase of tissue temperature, tissue oxygen partial pressure, and tissue blood flow, and by this regional metabolism. As fatty tissue normally has a slow metabolism (bradytrophic and hypothermic tissue) with a low rate of lipolysis, wIRA can increase lipolysis in fatty tissue and the mobilized fats are burned in musculature during the ergometer exercise. CONCLUSION: The results of the study indicate, that wIRA irradiation during moderate ergometer endurance exercise can be used - in combination with an appropriate nutrition - to improve body composition, especially local fat distribution, and the reduction of fat and body weight in obese persons.

19.
Ger Med Sci ; 2: Doc08, 2004 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-19675691

RESUMO

BACKGROUND: Common warts (verrucae vulgares) are human papilloma virus (HPV) infections with a high incidence and prevalence, most often affecting hands and feet, being able to impair quality of life. About 30 different therapeutic regimens described in literature reveal a lack of a single striking strategy. Recent publications showed positive results of photodynamic therapy (PDT) with 5-aminolevulinic acid (5-ALA) in the treatment of HPV-induced skin diseases, especially warts, using visible light (VIS) to stimulate an absorption band of endogenously formed protoporphyrin IX. Additional experiences adding waterfiltered infrared A (wIRA) during 5-ALA-PDT revealed positive effects. AIM OF THE STUDY: First prospective randomised controlled blind study including PDT and wIRA in the treatment of recalcitrant common hand and foot warts. Comparison of "5-ALA cream (ALA) vs. placebo cream (PLC)" and "irradiation with visible light and wIRA (VIS+wIRA) vs. irradiation with visible light alone (VIS)". METHODS: Pre-treatment with keratolysis (salicylic acid) and curettage. PDT treatment: topical application of 5-ALA (Medac) in "unguentum emulsificans aquosum" vs. placebo; irradiation: combination of VIS and a large amount of wIRA (Hydrosun) radiator type 501, 4 mm water cuvette, waterfiltered spectrum 590-1400 nm, contact-free, typically painless) vs. VIS alone. Post-treatment with retinoic acid ointment. One to three therapy cycles every 3 weeks. Main variable of interest: "Percent change of total wart area of each patient over the time" (18 weeks). Global judgement by patient and by physician and subjective rating of feeling/pain (visual analogue scales). 80 patients with therapy-resistant common hand and foot warts were assigned randomly into one of the four therapy groups with comparable numbers of warts at comparable sites in all groups. RESULTS: The individual total wart area decreased during 18 weeks in group 1 (ALA+VIS+wIRA) and in group 2 (PLC+VIS+wIRA) significantly more than in both groups without wIRA (group 3 (ALA+VIS) and 4 (PLC+VIS)): medians and interquartile ranges: -94% (-100%/-84%) vs. -99% (-100%/-71%) vs. -47% (-75%/0%) vs. -73% (-92%/-27%). After 18 weeks the two groups with wIRA differed remarkably from the two groups without wIRA: 42% vs. 7% completely cured patients; 72% vs. 34% vanished warts. Global judgement by patient and by physician and subjective rating of feeling was much better in the two groups with wIRA than in the two groups without wIRA. CONCLUSIONS: The above described complete treatment scheme of hand and foot warts (keratolysis, curettage, PDT treatment, irradiation with VIS+wIRA, retinoic acid ointment; three therapy cycles every 3 weeks) proved to be effective. Within this treatment scheme wIRA as non-invasive and painless treatment modality revealed to be an important, effective factor, while photodynamic therapy with 5-ALA in the described form did not contribute recognisably - neither alone (without wIRA) nor in combination with wIRA - to a clinical improvement. For future treatment of warts an even improved scheme is proposed: one treatment cycle (keratolysis, curettage, wIRA, without PDT) once a week for six to nine weeks.

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