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Purpose: This study compared different energy densities of laser on second degrees burns in rats aiming to determine the most effective dosimetry in stimulation of the healing process., Methods: Burns were induced in the dorsal skin of 54 animals divided into three groups (n: 18): 1-without treatment; 2-irradiated lesions by the Indium Gallium Phosphide (InGaP) 670nm (4.93J/cm 2 ) laser; 3-irradiated lesions by the InGaP-670nm (9.86J/cm 2 ) laser. Samples were collected on the 2, 10 and 18 days after injury for structural, morphometry, biochemical analysis and Western blotting., Results: The energy densities examined were effective in significantly increasing the total number of fibroblasts and blood vessels and reduce the number of inflammatory cells particularly in irradiated lesions with 9.86J/cm 2 . This same energy density significantly increased the amount of GAGs (Glycosaminoglycans), decreased the TGF-β1 (Transforming Growth Factor β1) and increased the VEGF (Vascular and Endothelial Growth Factor) during the experimental period. This energy density also significantly increased the Collagen type I and decreased Collagen type III and the active isoform of metalloproteinase 9 (MMP-9)., Conclusions: The energy density of 9.86J/cm 2 was more effective in promoting cellular responses related to neoangiogenesis, decreasing inflammation and collagen fibers reorganization., (Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.)

Introduction: In order to avoid epidermal heat damage, we developed a novel irradiation method termed "Focused multiple laser beams (FMLB)," which allows long-pulse neodymium:yttrium aluminum garnet (Nd:YAG) laser beams to be irradiated from several directions in a concentric fashion followed by focusing into the dermis without epidermal damage. This study aimed to assess whether FMLB achieves the desired dermal improvement without epidermal damage., Materials and Methods: The dorsal skin of New Zealand White rabbits was irradiated with FMLB. Macroscopic and histological analyses were performed after 1 hour and 1, 2, 3 and 4 weeks. Real-time PCR analysis of type I and III collagen expression was performed at two and four weeks., Results: Control groups exhibited skin ulcers which were healed with scar formation whereas FMLB groups remained intact macroscopically. Histologically, FMLB group showed increase in dermal thickness at four weeks while the epidermis remained intact. Real-time PCR demonstrated that both type I and III collagen increased at two weeks but decreased at four weeks., Conclusions: FMLB can deliver the target laser energy to the dermis without significantly affecting the epidermis.

Background: Monopolar radiofrequency (mRF) devices have been shown to be clinically effective for treating aging skin, but there are few histologic studies about the mechanisms., Objective: To histologically analyze chronologic and quantitative change in collagens after mRF treatment to determine the mechanisms of the antiaging effect., Methods: Five patients were enrolled in this study. Skin specimens were taken before and 1 and 3 months after treatment. Immunostaining was performed to determine change in type I and III collagen levels and stem and other cell counts in skin layers., Results: In all cases, both types of collagen significantly increased after irradiation in the dermis (p < .05), and their changes were noticed uniformly in all layers. No significant change was noticed in stem and other cell counts., Conclusions: This study histologically demonstrated that type I and III collagen increased significantly in the dermis after mRF treatment. The amount of stem cells did not affect the increase in collagens., (© 2014 by the American Society for Dermatologic Surgery, Inc. Published by Wiley Periodicals, Inc.)

Objective: Patients who have had pelvic radiotherapy as part of their cancer therapy may develop subsequent urinary bladder effects such as hyperactive bladder, incontinence, and dysuria. Therefore, the goal of this study was to evaluate whether glutamine supplementation could prevent collagen expression damage in healthy urinary bladder caused by radiotherapy., Methods: Fifteen adult Wistar rats were separated into a control group that received food and water ad libitum (C group), an irradiated group that received a single pelvic radiation dose of 1164 cGy (I group), and an irradiated group supplemented with l-glutamine every day during the entire experimental period (0.65 g/kg of body weight; I+G group). All animals were sacrificed 15 d after irradiation. The extracellular matrix and muscle were quantified by a morphometric method. Picro Sirius Red was used to visualize the different collagen types. Reverse transcription-polymerase chain reaction and immunohistochemistry were used to determine collagen type I and III expressions., Results: The extracellular matrix (C group 36.84±4.37, I group 31.64±5.00, I+G group 35.53±2.60, P=0.0001), muscle (C group 36.43±6.15, I group 29.39±7.08, I+G group 31.38±3.14, P=0.0001), and gene expressions of collagen type I (C group 1.067±0.31, I group 0.579±0.17, I+G group 1.816±0.66, P=0.0009) and type III (C group 0.99±0.28, I group 0.54±0.13, I+G group 1.07±0.28, P=0.0080) were decreased in the I group. Apart from muscle, glutamine supplementation prevented these alterations. Immunohistochemistry and Picro Sirius Red showed similar results., Conclusion: Supplementation with l-glutamine seems to prevent bladder wall damage in relation to extracellular matrix volumetric density and collagen expression. These results suggest that glutamine supplementation could be efficient in protecting healthy tissues from the adverse effects of radiotherapy., (Copyright © 2011. Published by Elsevier Inc.)

This study determined the effects of gallium-aluminum-arsenide laser (GaAlAs), gallium-arsenide laser (GaAs) and Dersani healing ointment on skin wounds in Wistar rats. The parameters analyzed were: type I and III collagen fiber concentrations as well as the rate of wound closure. Five wounds, 12 mm in diameter, were made on the animals' backs. The depth of the surgical incision was controlled by removing the epithelial tissue until the dorsal muscular fascia was exposed. The animals were anesthetized with ketamine and xylazine via intraperitoneal injection. The rats were randomly divided into five groups of 6 animals each, according to the treatment received. Group 1 (L4): GaAs laser (4 J/cm(2)); group 2 (L30): GaAlAs laser (30 J/cm(2)); group 3 (L60): GaAlAs laser (60 J/cm(2)); group 4 (D): Dersani ointment; group 5 (control): 0.9% saline. The applications were made daily over a period of 20 days. Tissue fragments were stained with picrosirius to distinguish type I collagen from type III collagen. The collagen fibers were photo-documented and analyzed using the Quantum software based on the primary color spectrum (red, yellow and blue). Significant results for wound closing rate were obtained for group 1 (L4), 7.37 mm/day. The highest concentration of type III collagen fibers was observed in group 2 (L30; 37.80 + or - 7.10%), which differed from control (29.86 + or - 5.15%) on the 20th day of treatment. The type I collagen fibers of group 1 (L4; 2.67 + or - 2.23%) and group 2 (L30; 2.87 + or - 2.40%) differed significantly from control (1.77 + or - 2.97%) on the 20th day of the experiment.

Background: Infrared irradiation stimulates collagen production, but histological differences in its long-term effects on type I versus type III collagen and elastin in human tissue are unclear., Objective: To investigate the effects of infrared irradiation., Methods and Materials: In vivo human tissues in sun-protected and sun-exposed areas were irradiated with infrared. Histological samples were analyzed, and visual changes were assessed up to 90 days post-treatment., Results: Infrared irradiation provided long-term increases in collagen and elastin levels on post-irradiation days 30, 60 and 90 compared to controls. Significant increases in type I collagen persisted until 30 and 60 days, and in sun-protected and exposed skin biopsies, respectively. Significant increases in type III collagen and elastin persisted until 90 days in both sun-protected and sun-exposed skin biopsies., Conclusion: Infrared irradiation provides safe and effective long-term stimulation of collagen I and III and elastin, which is beneficial for improving skin laxity and wrinkles.

Background: Skin aging consists of photoaging and intrinsic aging. It is characterized clinically not only by rhytides, but also by pigmentary alterations and facial telangiectasias. There continues to be a growing interest in the efficacy of intense pulsed light (IPL) devices in the treatment of skin aging, as well as further defining its mechanism of action., Objectives: The objective of this clinical trial was to evaluate the effects and the mechanism of action of an IPL by comparing clinical photographs and biopsy results before and after treatment., Methods: A total of 58 patients were treated using a new IPL device. Clinical photographs were taken before treatment and compared to those taken 3 weeks after the treatment. Also, 4 cases had pathological analyses of tissues that were stained by haematoxylin-eosin and Uana orcein. Immunohistology of human collagen of types 1 and 3 and quantitative analyses of elastin and collagen were performed by a poly-functional digital image light microscope; a transmission electron microscope was used for 2 of the cases to look for additional changes., Results: After 3 treatments, 62.1% of the patients showed improvement in wrinkles and skin texture. Pigmentation improved in 84.6% of the patients, and a reduction in telangiectasis was seen in 81.25% of the patients. Pathological examination showed that both type 1 and type 3 collagens increased following treatment, but elastin content decreased; however, the elastin fibers were arranged more neatly. In the transmission electron microscope study, the amount of fibroblast activity increased, the fibroblasts were more active, and there were more collagen fibers neatly rearranged within the stroma., Conclusion: Clinical and pathological studies demonstrated that the IPL was effective in improving wrinkles and skin texture. The mechanism of action may be through the increasing activity of the fibroblasts, hyperplasia of the fibroblasts, and rearrangement of both collagen and elastin within the stroma.

Objective: To investigate the effects of quercetin and X-ray on collagen synthesis of cultured human keloid-derived fibroblast and the mechanism., Methods: Collagen synthesis of cultured human keloid and normal fibroblasts were detected by hydroxyproline colorimetric analysis. Immunocytochemical staining was used to investigate collagen I and III expression. mRNA expression of collagen I and III, and transforming growth factor (TGF)-beta 1 were assayed by reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR., Results: Quercetin inhibited the collagen synthesis of both keloid and normal fibroblasts in a dose-dependent manner. Immunocytochemical staining indicated that collagen I and III were down-regulated by quercetin and X-ray (P < 0.05), particularly collagen I (P < 0.05). mRNA expression of both collagen I and III in quercetin groups significantly decreased compared with that in control group (P < 0.05), especially in the group treated with both quercetin and X-ray (P < 0.01). mRNA level of TGF-beta 1 gene was down-regulated by quercertin (P < 0.05)., Conclusions: Quercetin will probably be one of the new medicines which could effectively treat keloid. Quercetin combined with X-ray could reduce the dose of radiation.

Exposure to gamma ray irradiation is a frequent, clean, and superior method used to prevent bacterial contamination of sterilized biomedical end products. However, the potential damage induced by gamma ray irradiation of collagen is of concern because of the decay of bioactivity, which correlates with considerable structural alterations. In this experiment, antenna-coupling microwave plasma was utilized to activate nonwoven polypropylene (PP) fabric, and then the sample was grafted to acrylic acid (AAc). Type III collagen was immobilized by using water-soluble 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide as a coupling agent. The collagen-immobilized samples, with temperatures of under 4 degrees C, were exposed to gamma ray irradiation at different dose intervals. Gamma ray irradiation was applied to evaluate the bioactivity on the collagen-immobilized nonwoven polypropylene and to determine the results of sterilization. Five kinds of sterilization index bacteria, all subject to Good Manufacturing Practice (GMP) criteria, were applied as a standard plate-count sterilization test. Our experimental results demonstrate that in human plasma incubated with various intervals of gamma ray irradiation, fibrinogen concentration decreases while platelet and red blood cell adhesion increase. However, the dose required for thrombination demonstrated a significant change in gamma ray irradiation exposure of fewer than 10 KGy (p = 0.05). The decay of bioactivity of the gamma-ray-irradiated collagen-bonded surfaces was evaluated and indicated that the decrease of R-CONHR', the degradation of amides ([broken bond]C[bond]N bonds of collagen and formation of the ROCNH(2) and O[double bond]CR' bonds), and the increase of C[bond]O, C[double bond]O bonds gradually may damage collagen by increasing the intervals of gamma ray irradiation. These effects considerably influence the bioactivity of the collagen-bonded fabric. It is clear that gamma ray irradiation exposure of approximately 10 KGy has the potential of moderating the bioactivities of collagen and therefore likely is a vital factor in the acceleration of biodegradation. The dose required for thrombination and sterilization reaches significance at 7.5 KGy., (Copyright 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 1033-1043, 2003)

Systemic and pulmonary hypertension is characterised by structural reconstruction of the vascular wall which includes hypertrophy and hyperplasia of vascular smooth muscle cells (VSMCs) and fibroproduction. We hypothesise that these changes are stimulated by non-enzymatic modification of collagen molecules in the injured vascular wall by radicals. We exposed collagen III to ultraviolet (UV) light irradiation which, as indicated by fluorescence and electrophoretic analyses, resulted in its fragmentation. Both irradiated and control unmodified collagen were adsorbed on culture dishes and seeded with VSMCs derived from the rat thoracic aorta. During the first week after seeding, the cells on the modified collagen attained significantly higher population density (by 15-83%), higher mitotic index (by 31-135%) and higher BrdU labelling index (by 32%). However, these cells were less resistant to spontaneous and trypsin-mediated detachment from the growth support. As revealed using enzyme-linked immunosorbent assay in 3-day-old cultures, the cells growing on the irradiated collagen exhibited a lower concentration of beta-1 integrins (-10%, measured per milligram of protein), vinculin (-18%), talin (-6%) and vimentin (-15%). Immunofluorescence staining showed that these molecules were distributed more diffusely and less organised into focal adhesion plaques or cytoskeletal fibres. The concentration of two adhesion molecules of immunoglobulin type, ICAM-1 and VCAM-1, was increased by 11% and 16%, respectively. The concentration of alpha-v integrins and alpha-actin was unchanged; the latter, however, formed fewer distinct microfilament bundles in cells on the modified collagen. Our results suggest that the VSMCs growing on UV-modified collagen are more prone to escape the growth control mediated by cell-extracellular matrix contact and can bind the cells of the immune system.