An Ocimum basilicum Extract Containing Rosmarinic Acid Restores the Disruption of Collagen Fibers Caused by Repetitive UVA Irradiation of Dermal Fibroblasts.

Photoaged skin is characterized by the appearance of pigmented spots such as solar lentigos, deep wrinkles and sags, and progresses due to chronic sun exposure. Among the wavelengths of sunlight, UVA is responsible for the appearance of wrinkles and sags that originate from structural alterations in the dermis of photoaged skin such as the depletion of collagen fibers. Thus, improving and restoring collagen fibers is an effective approach to reduce skin photoaging and maintain a youthful appearance. This study was conducted to evaluate the potential of an extract of Ocimum basilicum (OC), which contains rosmarinic acid (RA), as an anti-photoaging material focusing on the capacity to restore collagen fibers that are disrupted due to intracellular oxidative stress. In spite of their relatively low capacities for chemical scavenging of reactive oxygen species (ROS), both OC and RA showed efficient removal of biological oxidative stress by reducing levels of intracellular ROS and carbonylated proteins (CPs) in fibroblasts following exposure to single or repetitive UVA irradiations. Fibroblasts irradiated with repetitive UVA as a model for chronic sun-exposed cells showed significant increases in matrix metalloproteinase-1 and decreases in type I collagen synthesis and formed reduced numbers of collagen fibers. Since both OC and RA restored the adverse phenomena caused by repetitive UVA irradiation, we conclude that OC containing RA is an effective anti-photoaging material.

Pueraria montana var. lobata root extract inhibits photoaging on skin through Nrf2 pathway.

Pueraria montana var. lobata is a bioactive substance, in possession of a variety of beneficial health effects, which has long been extensively used as a traditional medication for the treatment of fever, acute dysentery, diabetes, and cardiovascular diseases in North-East Asian countries. The purpose of this study was to evaluate the cytoprotective activity of Pueraria montana var. lobata ethanol extract (PLE) for ultraviolet B (UVB) induced oxidative stress in human dermal fibroblasts (HDF). It was hypothesized that PLE treatment (25-100 µg/mL) would reduce intracellular reactive oxygen species (ROS) levels as well as increase collagen production in UVB-irradiated HDF. The results confirmed this theory, with collagen production increasing in the PLE treatment group in a dose-dependent manner. In addition, regulators of cellular ROS accumulation, including HO-1 and NOQ-1, were activated by Nrf2, which was mediated by PLE. Hence, intracellular levels of ROS were also reduced in the PLE treatment group in a dose-dependent manner. In conclusion, PLE increases collagen production and maintains hyaluronic acid (HA) levels in human dermal fibroblasts exposed to UVB-irradiation, thereby inhibiting photoaging.

Accelerated collagen cross-linking in the management of advanced Acanthamoeba keratitis / Cross-linking acelerado de colágeno no controle da ceratite por Acanthamoeba avançada

ABSTRACT Purpose: To report our initial experience in the treatment of Acanthamoeba keratitis with accelerated corneal collagen cross-linking. Methods: Retrospective chart review of patients diagnosed with Acanthamoeba keratitis with progressive corneal melting who were treated with accelerated collagen cross-linking. Results: A total of 6 eyes (5 patients) were reviewed. All the patients received adjuvant therapy with moxifloxacin and chlorhexidine. In 4 cases, the ulcer healed with a mean interval to epithelialization of 108.8 days (range 59-217). In 2 eyes, there was a persistent neurotrophic ulcer. The melting was not progressive in any case, nor did any eye required emergency penetrating keratoplasy. Conclusion: This study suggests a beneficial effect of accelerated collagen cross-linking in cases of Acanthamoeba keratitis with corneal melting. Thus, collagen cross-linking may be considered as adjuvant treatment for Acanthamoeba keratitis.

RESUMO Objetivo: Relatar nossa experiência inicial no tra tamento da ceratite por Acanthamoeba com reticulação acelerada de colágeno corneano. Métodos: Revisão retrospectiva de prontuários de pacientes diagnosticados com ceratite por Acanthamoeba, com deformação progressiva da córnea, tratados com reticulação acelerada de colágeno. Resultados: Seis olhos (5 pacientes) foram incluídos. Todos os pacientes receberam terapia adjuvante com moxifloxacina e clorexidina. Em 4 casos, a úlcera cicatrizou com uma média de epitelização de 108,8 dias (amplitude de 59-217 dias). Em dois pacientes, a úlcera apresentou um comportamento neurotrófico. A deformação não foi progressiva em nenhum dos pacientes e nenhum dos olhos exigiu ceratoplastia penetrante de emergência. Conclusão: Este estudo sugeriu um efeito benéfico da reticulação acelerada de colágeno em casos de ceratite por Acanthamoeba infecciosa com deformação corneal. A reticulação de colágeno parece ser uma alternativa coadjuvante possível para casos de ceratite por Acanthamoeba.

Accelerated collagen cross-linking in the management of advanced Acanthamoeba keratitis.

PURPOSE: To report our initial experience in the treatment of Acanthamoeba keratitis with accelerated corneal collagen cross-linking. METHODS: Retrospective chart review of patients diagnosed with Acanthamoeba keratitis with progressive corneal melting who were treated with accelerated collagen cross-linking. RESULTS: A total of 6 eyes (5 patients) were reviewed. All the patients received adjuvant therapy with moxifloxacin and chlorhexidine. In 4 cases, the ulcer healed with a mean interval to epithelialization of 108.8 days (range 59-217). In 2 eyes, there was a persistent neurotrophic ulcer. The melting was not progressive in any case, nor did any eye required emergency penetrating keratoplasy. CONCLUSION: This study suggests a beneficial effect of accelerated collagen cross-linking in cases of Acanthamoeba keratitis with corneal melting. Thus, collagen cross-linking may be considered as adjuvant treatment for Acanthamoeba keratitis.

Effect of 670 nm laser photobiomodulation on vascular density and fibroplasia in late stages of tissue repair.

This study aimed to investigate the effects of gallium-aluminum-arsenium (GaAlAs) (670 nm) laser therapy on neoangiogenesis and fibroplasia during tissue remodelling. Forty male Wistar rats underwent cutaneous surgery and were divided into 2 experimental groups: the Control and Laser group (9 mW, 670 nm, 0.031 W/cm2 , 4 J/cm2 ). After 14, 21, 28, and 35 days, the animals were euthanised. Descriptive and quantitative analyses were performed in sections stained with haematoxylin-eosin and Sirius Red, respectively. The amounts of VEGF+ and CD31+ cells were evaluated by immunohistochemistry and histomorphometric analysis, respectively. Statistical analysis was performed using the Mann-Whitney, Friedman, and Spearman correlation test, P < 0.05. The collagen expression was significantly higher in the laser group compared with the control group on days 14 and 21 after the creation of the skin wound (P = 0.008; P = 0.016) and in the control group between 14 and 28 and 14 and 35 days (P = 0.001; P = 0.007). There were more blood vessels in three periods of the study only in the (Laser) treated group, with statistical significance at day 14 (P = 0.016). There was no statistically significant difference in VEGF+ cell count in the different experimental groups throughout the study, although a positive correlation was shown with the area of collagen on days 14 and 28 (P = 0.037). Laser treatment had a positive effect in the late course of healing, particularly with regards to collagen expression and the number of newly formed vessels. VEGF+ cells were present in both experimental groups, and VEGF appeared to influence fibroplasia in the treated group.

The efficacy of supplementary sonic irrigation using the EndoActivator® system determined by removal of a collagen film from an ex vivo model.

AIM: To evaluate the efficacy of sonic irrigation (EndoActivator® ) using various polymer tips and power settings in a stained collagen ex vivo model. METHODOLOGY: The root canals of fifty human, straight single-rooted extracted teeth were prepared to size 40, .08 taper. The roots were split longitudinally; stained collagen applied to the canal surfaces, photographed and re-assembled. The canals were subjected to syringe without supplementary (group 1, n = 10) or with supplementary sonic (groups 2-5, n = 10) irrigation. EndoActivator® tip sizes (size 15, .02 taper for groups 2 and 3; size 35, .04 taper for groups 4 and 5) and power settings (low for groups 2 and 4; high for groups 3 and 5) were tested. After irrigation, the canals were re-photographed and the area of residual stained collagen was quantified using the UTHSCA Image Tool program (Version 3.0). The data were analysed using Wilcoxon signed rank test and general linear mixed models. RESULTS: Supplementary sonic irrigation using EndoActivator® resulted in significantly (P < 0.0001) less residual collagen compared with syringe irrigation only. Agitation of irrigant using the large EndoActivator® tip with high power resulted in significantly less (22.4% - 29.5%) residual collagen compared to other combinations (large tip/low power P = 0.001; small tip/low power P = 0.01; small tip/high power P = 0.04). There was no significant difference amongst the latter three groups (P > 0.5). CONCLUSIONS: Supplementary sonic irrigation using the EndoActivator® system was significantly more effective in removing stained collagen from the canal surface than syringe irrigation alone. EndoActivator® used with large tip (size 35, .04 taper) and high power setting in size 40, .08 taper canals was more effective than other combinations.

Treatment of pseudoxanthoma elasticum-like papillary dermal elastolysis with nonablative fractional resurfacing laser resulting in clinical and histologic improvement in elastin and collagen.

OBJECTIVE: Pseudoxanthoma elasticum-like papillary dermal elastolysis (PXE-PDE) is a rare skin condition seen predominantly in elderly females. These asymptomatic lesions are brought to the dermatologist's attention due to patient's displeasure in their appearance. We report a case of a 28-year-old female with PXE-PDE on the right neck treated with nonablative fractional resurfacing (NAFR). CASE: The patient on examination had yellow-to-skin-colored papules that coalesced into a cobblestone-appearing plaque on her lateral neck. The area was treated with NAFR to improve texture and cosmesis. After three treatments, the patient noted at least a 50% improvement of appearance and texture in the affected skin. Adverse effects were mild without development of serious side effects, such as scarring and/or permanent dyspigmenation. CONCLUSION: Established therapies for elastin disorders like PXE-PDE have yielded unsatisfactory results by patient and clinician standards. Positive results with NAFR, illustrated in our PXE-PDE case, further provides a role for NAFR in elastin disorders.

Experimental burns: Comparison between silver sulfadiazine and photobiomodulation.

OBJECTIVE: To analyze morphological characteristics and organization of the collagen fibers of third degree burns from scalding compared to laser therapy and silver sulfadiazine, the latter considered as the gold standard. METHOD: Were selected 12 animals (Rattus norvegicus) also divided into three groups (control group [CG] - untreated burns; sulfadiazine group [SG] - burns were treated with silver sulfadiazine at 1%; laser group [LG] - burns were treated with photobiomodulation). The scald burns were carried out by using PVC mold, and the material collected on the 14th day after burn was prepared for morphological and optical retardation analysis for evaluation of inflammatory infiltrates and collagen organization, respectively. RESULTS: On the 14th day, the laser and sulfadiazine groups had mild inflammatory response, while the control group showed an intense inflammatory process, with statistical significance between laser and control groups, but not between sulfadiazine and control groups. Laser and sulfadiazine groups no longer had granulation tissue, opposite to what was seen in the control group. The presence of hair follicles and ulcer did not significantly differ between groups. The optical retardation of collagen fibers was higher in sulfadiazine group, followed by laser and control groups. As for systemic effect, we were able to identify it by simply analyzing the presence or absence of granulation tissue. CONCLUSION: Morphologically, the laser or silver sulfadiazine treatments were similar and both provided better organization of collagen fibers in relation to the untreated group. However, the sulfadiazine group modulated the deposition of collagen fibers more efficiently than the laser group.

Experimental burns: Comparison between silver sulfadiazine and photobiomodulation / Queimadura experimental: comparativo entre sulfadiazina de prata e fotobiomodulação

Summary Objective: To analyze morphological characteristics and organization of the collagen fibers of third degree burns from scalding compared to laser therapy and silver sulfadiazine, the latter considered as the gold standard. Method: Were selected 12 animals (Rattus norvegicus) also divided into three groups (control group [CG] - untreated burns; sulfadiazine group [SG] - burns were treated with silver sulfadiazine at 1%; laser group [LG] - burns were treated with photobiomodulation). The scald burns were carried out by using PVC mold, and the material collected on the 14th day after burn was prepared for morphological and optical retardation analysis for evaluation of inflammatory infiltrates and collagen organization, respectively. Results: On the 14th day, the laser and sulfadiazine groups had mild inflammatory response, while the control group showed an intense inflammatory process, with statistical significance between laser and control groups, but not between sulfadiazine and control groups. Laser and sulfadiazine groups no longer had granulation tissue, opposite to what was seen in the control group. The presence of hair follicles and ulcer did not significantly differ between groups. The optical retardation of collagen fibers was higher in sulfadiazine group, followed by laser and control groups. As for systemic effect, we were able to identify it by simply analyzing the presence or absence of granulation tissue. Conclusion: Morphologically, the laser or silver sulfadiazine treatments were similar and both provided better organization of collagen fibers in relation to the untreated group. However, the sulfadiazine group modulated the deposition of collagen fibers more efficiently than the laser group.

Resumo Objetivo: Analisar características morfológicas e organização das fibras colágenas de queimaduras de terceiro grau provocadas por escaldo em relação à terapia com laser e àquela considerada padrão-ouro, a sulfadiazina de prata. Método: Foram selecionados 12 animais (Rattus norvegicus), divididos igualmente em três grupos (grupo controle [GC] - queimaduras não tratadas; grupo sulfadiazina [GS] - queimaduras tratadas com sulfadiazina de prata 1%; grupo laser [GL] - queimaduras tratadas com fotobiomodulação). As queimaduras foram realizadas por escaldo com a utilização de molde de PVC, e o material coletado no 14º dia pós-queimadura foi preparado para análise morfológica e de retardo óptico, para avaliação do infiltrado inflamatório e da organização do colágeno, respectivamente. Resultados: No 14º dia, os grupos laser e sulfadiazina apresentaram resposta inflamatória leve, enquanto o grupo controle apresentou processo inflamatório intenso, havendo significância estatística entre os grupos laser e controle, mas não entre os grupos sulfadiazina e controle. Enquanto os grupos laser e sulfadiazina não apresentavam mais tecido de granulação, o grupo controle ainda apresentava. A presença de folículo piloso e de úlcera não diferiu significantemente entre os grupos. O retardo óptico das fibras colágenas foi maior no grupo sulfadiazina, seguido dos grupos laser e controle. Apenas a análise da presença ou ausência de tecido de granulação permitiu identificar o efeito sistêmico. Conclusão: Morfologicamente, os tratamentos com laser ou sulfadiazina de prata foram similares e ambos proporcionaram maior organização das fibras colágenas em relação ao grupo não tratado. Entretanto, o grupo sulfadiazina modulou a deposição das fibras colágenas mais eficientemente que o grupo laser.

Phototherapy for sclerosing skin conditions.

Phototherapy is an effective treatment strategy for a variety of sclerosing skin conditions. There are a number of phototherapeutic modalities used for the treatment of sclerosing skin conditions, including ultraviolet (UV)A1, broadband UVA, psoralen plus UVA, and narrowband UVB phototherapy. As controlled trials with validated outcome measures are lacking for these therapies, existing evidence is largely level II for morphea and is even more minimal for scleroderma and other sclerosing disorders (scleroderma, lichen sclerosus, and chronic graft-versus-host disease, among others). Studies do suggest that phototherapy may be effective for many of these disorders, including those that have been unresponsive to other therapies. Phototherapy remains an attractive therapeutic option for patients due to its efficacy and favorable risk-versus-benefit profile. Phototherapy also offers a therapeutic alternative to systemic immunosuppressives for patients who cannot tolerate these medications.

Effects of neodymium-yttrium-aluminum garnet (Nd:YAG) pulsed high-intensity laser therapy on full thickness wound healing in an experimental animal model.

OBJECTIVE: Wound healing can be aided by the use of low- and medium-intensity lasers. The use of pulsed neodymium-doped yttrium aluminum garnet (Nd:YAG) high-intensity laser therapy (HILT) with a 1064-nm wavelength laser provides deeper and more efficient penetration into tissue as it is being less absorbed by chromophores in tissue, e.g., hemoglobin, melanin, and water, thereby enhancing the wound-healing process. In this study, we examined the effect of HILT on wound healing with a Q-switched pulsed Nd:YAG laser in an animal model. DESIGN: Sixty SKH1 hairless male mice (seven weeks old) were randomly divided into four groups according to the amount of laser fluence: control, group 1 (0.8 J/cm2), group 2 (1.6 J/cm2), and group 3 (2.0 J/cm2). Laser treatment was provided to groups 1, 2, and 3 with a 1064-nm Q-switched Nd:YAG laser. Histological analysis was performed with hematoxylin and eosin staining, Masson's Trichrome staining, and Ki-67 staining. RESULTS: Statistically significant increases in the accumulation of collagen fibers, thickness of granulation tissue, and numbers of fibroblasts were observed in group 2 (treated with 1.6 J/cm2) as compared with the control (no laser treatment), group 1 (treated with 0.8 J/cm2), and group 3 (treated with 2.0 J/cm2). CONCLUSION: Nd:YAG HILT stimulated fibroblast proliferation and increased extracellular matrix production. We expect that this therapy could accelerate the wound-healing process.

Effects of L-Glutamine oral supplementation on prostate of irradiated rats.

OBJECTIVES: To investigate the protective effect of L-Glutamine in animals undergone to ventral radiation when the target organ is not the prostate. MATERIALS AND METHODS: Wistar rats were divided into groups of 10 animals each: Controls (C), maintained under standard conditions and not exposed to radiation, Radiated group (R) undergone to abdominal radiation only and Radiated plus supplemented by L-glutamine group (R+G). The animals of group R+G were supplemented with L-glutamine at the beginning of the experiment until death in the 22nd day. The ventral prostate was dissected and processed for morphometrical analysis. The epithelial height, collagen density and acinar area were objectively assessed in histological sections. RESULTS: Epithelial height was significantly reduced in R group in comparison to C group (p= 0.005). However, there was no statistical difference between the C and R+G groups. Collagen surface density in the C and R groups were not statistically different, but a significant difference was observed when comparing groups R+G and R (p=0.040). The R+G group values did not differ significantly from C group. The acinar prostate area of group R was similar to that of C (p= 0.971), but in R+G it was significantly reduced when compared with the C (p= 0.038) and R (p= 0.001) groups. CONCLUSIONS: Pelvic radiation promotes structural modifications in ventral prostate of rats, which can be reduced by L-Glutamine.

Skin healing and collagen changes of rats after fractional erbium:yttrium aluminum garnet laser: observation by reflectance confocal microscopy with confirmed histological evidence.

The fractional erbium:yttrium aluminum garnet (Er:YAG) laser is widely applied. Microstructural changes after laser treatment have been observed with histopathology. Epidermal and dermal microstructures have also been analyzed using reflectance confocal microscopy (RCM). However, no studies have compared these two types of microstructural changes in the same subject at multiple time points after irradiation, and it is unclear if these two types of changes are consistent. We use RCM to observe the effect of different laser energies on skin healing and collagen changes in the skin of Sprague-Dawley rats that had been irradiated by fractional Er:YAG lasering at different energies. RCM was used to observe skin healing and detect collagen changes at different time points. Collagen changes were observed using hematoxylin and eosin (H&E) staining and quantitatively analyzed by western blot. RCM showed that, irrespective of laser energy, microscopic treatment zones (MTZs) were larger at 1 day after irradiation. The MTZs then reduced in size from 3 to 7 days after irradiation. The higher the energy, the larger the MTZ area. The amount of collagen also increased with time from 1 day to 8 weeks. However, the increase in the collagen amount on both RCM and H&E staining was not influenced by the laser energy. Western blotting confirmed that the amount of type I and type III collagens increased over time, but there were no significant differences between the different energy groups (p > 0.05). In conclusion, RCM is a reliable technique for observing and evaluating skin healing and collagen expression after laser irradiation.

Effects of L-Glutamine oral supplementation on prostate of irradiated rats

ABSTRACT Objectives To investigate the protective effect of L-Glutamine in animals undergone to ventral radiation when the target organ is not the prostate. Materials and Methods Wistar rats were divided into groups of 10 animals each: Controls (C), maintained under standard conditions and not exposed to radiation, Radiated group (R) undergone to abdominal radiation only and Radiated plus supplemented by L-glutamine group (R+G). The animals of group R+G were supplemented with L-glutamine at the beginning of the experiment until death in the 22nd day. The ventral prostate was dissected and processed for morphometrical analysis. The epithelial height, collagen density and acinar area were objectively assessed in histological sections. Results Epithelial height was significantly reduced in R group in comparison to C group (p= 0.005). However, there was no statistical difference between the C and R+G groups. Collagen surface density in the C and R groups were not statistically different, but a significant difference was observed when comparing groups R+G and R (p= 0.040). The R+G group values did not differ significantly from C group. The acinar prostate area of group R was similar to that of C (p= 0.971), but in R+G it was significantly reduced when compared with the C (p= 0.038) and R (p= 0.001) groups. Conclusions Pelvic radiation promotes structural modifications in ventral prostate of rats, which can be reduced by L-Glutamine.

Laser and Light Treatments for Striae Distensae: A Comprehensive Review of the Literature.

Striae distensae (SD) are common dermatologic lesions that often arise as a result of rapid weight change, certain endocrine conditions, or prolonged exposure to steroids. SD initially present as raised edematous plaques (striae rubra), after which they become white and atrophic (striae alba) owing to local breakdown and reorganization of collagen and elastin. There currently exists no reliable treatment option, though numerous topical applications have been attempted. Lasers and light represent emerging noninvasive therapies that have demonstrated some success targeting vascular chromophores in striae rubra and stimulating collagen and elastin production in striae alba. An extensive literature review was performed to gather all available articles studying laser and light treatments for SD. Lasers and light can significantly improve the appearance of both striae rubra and striae alba. Generally, striae rubra are more responsive to therapy and can be treated successfully with a variety of lasers without major adverse effects. Fractional lasers exhibit the strongest results for striae alba repigmentation and collagen induction, and several other lasers produce temporary repigmentation. Lasers in combination with other modalities such as topical agents and additional energy devices have also demonstrated promising preliminary results; however, large comparative studies are necessary to validate these outcomes.

Radiofrequency preserves histoarchitecture and enhances collagen synthesis in experimental tendon injury.

We investigated the action of radiofrequency (RF) on the healing process after inducing experimental lesions of the Achilles tendon in rats. Wistar rats were surgically subjected to bilateral partial transverse sectioning of the Achilles tendon. The right tendon was treated with radiofrequency (RFT), whereas the left tendon served as a control (CT). On the third postoperative day, the rats were divided into three experimental groups consisting of ten rats each, which were treated with monopolar radiofrequency (Tonederm™) until they were sacrificed on the 7th, 14th or 28th days. The histological specimens were studied for inflammatory cell content, collagen types I and III, immunostaining and morphometry. Total collagen were biochemically analyzed and to evalute fibroblast and myofibroblast proliferation by vimentin and α-actin smooth muscle immunohistochemistry methods. Statistical analysis was performed using the Student's t-test, the sign test and the Kruskal-Wallis test to compare tendons treated with radiofrequency with the non-treated tendons (α=5%; α=10%). Larger amounts of collagen I with hydroxyproline content and myofibroblast cells were clearly evident within 7 days (p<0.05). No difference was observed in the inflammatory cell content between the groups. We found better collagen arrangement with RF administration across the entire time studied. Radiofrequency administration preserves histoarchitecture and enhances collagen synthesis during the initial phases of cicatrization, suggesting that the treatment can provide improved stiffness during the most vulnerable phases of tendon healing. Clinical studies may include RF among the therapeutic tools in tendinous lesion management.

Analysis of the healing process of the wounds occurring in rats using laser therapy in association with hydrocolloid.

PURPOSE: To evaluate wound healing in rats by using low-level laser therapy (LLLT) associated with hydrocolloid occlusive dressing. METHODS: Forty male, adult, Wistar rats were used, distributed into four groups: LG (received 2 J/cm² of laser therapy); HG (treated with hydrocolloid); LHG (treated with 2 J/cm² of laser therapy and hydrocolloid); and the CG (treated with 1 mL of 0.9% saline). The wound was evaluated at pre-determined periods 3rd and 7th days, considering the macroscopic and histological parameters (inflammatory cells, capillary neoformation, fibroblasts, collagen formation and reepithelialization). RESULTS: The LG group at seven days showed increased collagen formation, the LHG group at 3 days showed mild collagen formation. The HG group and the CG at 7 days showed complete reepithelialization. CONCLUSION: Low-level laser therapy as well as the hydrocolloid dressing have favored the wound-healing process in rats.

Analysis of the healing process of the wounds occurring in rats using lasertherapy in association with hydrocolloid

PURPOSE: To evaluate wound healing in rats by using low-level laser therapy (LLLT) associated with hydrocolloid occlusive dressing. METHODS: Forty male, adult, Wistar rats were used, distributed into four groups: LG (received 2 J/cm² of laser therapy); HG (treated with hydrocolloid); LHG (treated with 2 J/cm² of laser therapy and hydrocolloid); and the CG (treated with 1 mL of 0.9% saline). The wound was evaluated at pre-determined periods 3rd and 7th days, considering the macroscopic and histological parameters (inflammatory cells, capillary neoformation, fibroblasts, collagen formation and reepithelialization).RESULTS: The LG group at seven days showed increased collagen formation, the LHG group at 3 days showed mild collagen formation. The HG group and the CG at 7 days showed complete reepithelialization.CONCLUSION: Low-level laser therapy as well as the hydrocolloid dressing have favored the wound-healing process in rats.

Phototherapy promotes healing of cutaneous wounds in undernourished rats

BACKGROUND: Various studies have shown that phototherapy promotes the healing of cutaneous wounds. OBJECTIVE: To investigate the effect of phototherapy on healing of cutaneous wounds in nourished and undernourished rats. METHODS: Forty rats, 20 nourished plus 20 others rendered marasmus with undernourishment, were assigned to four equal groups: nourished sham, nourished Light Emitting Diode treated, undernourished sham and undernourished Light Emitting Diode treated. In the two treated groups, two 8-mm punch wounds made on the dorsum of each rat were irradiated three times per week with 3 J/cm2 sq cm of combined 660 and 890nm light; wounds in the other groups were not irradiated. Wounds were evaluated with digital photography and image analysis, either on day 7 or day 14, with biopsies obtained on day 14 for histological studies. RESULTS: Undernourishment retarded the mean healing rate of the undernourished sham wounds (p < 0.01), but not the undernourished Light emission diode treated wounds, which healed significantly faster (p < 0.001) and as fast as the two nourished groups. Histological analysis showed a smaller percentage of collagen in the undernourished sham group compared with the three other groups, thus confirming our photographic image analysis data. CONCLUSION: Phototherapy reverses the adverse healing effects of undernourishment. Similar beneficial effects may be achieved in patients with poor nutritional status. .