Caracterização de colágenos tipos I e III no estroma do carcinoma de células escamosas cutâneo em cães

Evaluation of the alcoholic extract of Dipteryx alata Vogel almonds and bark in skin wound healing in C57BL6 mice

ABSTRACT The aim of this study was to evaluate the topical application of alcoholic extracts of Dipteryx alata Vogel almonds and bark in skin wound healing in mice. Fifty-four C57BL/6 mice were equally distributed into three groups: Control, Almond, and Bark. A 9 mm skin fragment was resected from the dorsal region of the animals’ thorax. The wounds were submitted to topical application of base cream (vehicle), 10% hydroalcoholic almond extract, or bark extract twice a day. Macroscopic, histological, and immunohistochemical evaluations were conducted on the 7th, 14th, and 21st postoperative days. No significant difference was observed regarding skin wound area among groups, with the parameter presenting only a temporal effect on healing (p>0.05). The almond and control groups exhibited more intense collagenization than the bark group (p<0.05). Dipteryx alata Vogel showed to be inert in the wound healing process in mice.

Macroscopic and Histological Morphology of the Equine Digital Cushion and Its Association with Subcutaneous Fat Thickness

This study evaluated the influence of the Body Condition Score (BCS) and subcutaneous fat thickness on the tissue composition of the digital cushion in horses. Sixty mixed breeds of Criollo horses (21 males and 39 females) were sent for slaughter. All animals were submitted to BCS analysis, through visual antemortem evaluation, and then ultrasound evaluation to estimate the subcutaneous fat thickness. Macroscopic analyses of the thoracic and a pelvic limb (weight, volume, and density of the hooves and digital cushions) were performed. In addition, measurements of the area of internal structures to the hoof and histological analyzes were carried out to measure the areas of adipose, fibroelastic, and collagen fibers of the digital cushion. There were no macroscopic differences in the digital cushion between thoracic and pelvic limbs or between genders (P > .05). Likewise, the histological characteristics between the limbs and the genders were similar (P > .05). There was no correlation between the weight, volume, and density of the digital cushion with the BCS (P > .05). A positive correlation was observed with the area of adipose tissue (P = .038, R² = 0.28) and a negative correlation with area of fibroelastic tissue (P = .005, R² = -0.37) and collagen fibers (P = .003, R² = -0.39). In conclusion, the adipose tissue, fibroelastic tissue, and collagen fibers of equine digital cushion alter their areas in the functions of the various subcutaneous fat patterns in horses.

Evaluation of angiogenesis, inflammation, and healing on irradiated skin graft with low-level laser therapy in rats (Rattus norvegicus albinus wistar)

The reconstructive techniques have been widely used in Veterinary Medicine. The post-operative adjuvants therapies like the low-level laser therapy (LLLT) are used to decrease inherent complications to reconstructive surgeries. This article purposed to define the LLLT effects on the healing, inflammation, and vascularization of the skin grafts in applicable time intervals to veterinary surgical routine. Forty rats (Rattus norvegicus albinus wistar) were used and each one was submitted to autogenous cutaneous mesh grafting in the interescapular region. The rats were randomly distributed in five groups (G1, G2, G3, G4, and G5) in accordance with the 6 J/cm² or 10 J/cm² dose every 3 or 5 days. These treatments were applied on the skin graft for 15 days. The histochemical evaluation with Picrosirius showed greater expression of collagen type 1 - red in grafts of G5 (p < 0.05), while in G1 did not; the expression of collagen type III - green was not induced by LLLT. The histochemical evaluation with hematoxylin-eosin showed greater numbers of fibroblasts in grafts of G4 (p < 0.05) and less hemorrhage in grafts of G5 (p < 0.05). There was modulation of the inflammatory response in irradiated skin grafts. It is concluded the exhibition of the skin grafts to 6 J/cm² or 10 J/cm² dose every 5 days improved the healing and the modulation of the local inflammation.

Photodynamic Therapy Versus Glucose for the Treatment of Telangiectasia: A Randomised Controlled Study in a Rabbit Ear Model

OBJECTIVES

Telangiectasia is a common venous formation that mainly affects women and causes discomfort, including psychological distress. This study compared photodynamic therapy (PDT) with glucose for vessel sclerosis in a rabbit ear model.

METHODS

Thirty-six ears of 18 rabbits were randomly divided into four groups: Group 1: only injection of Photogem (4 mg/mL); Group 2: only light (635 nm, 100 mW/cm², 8 min, 48 J/cm²); Group 3: glucose 75% injection; Group 4: PDT procedure with injection of Photogem and illumination immediately after. Injections were made into the central ear artery. After injection or sham procedures, manual compression of the marginal vein was maintained for 8 min in all ears. Follow up was immediately after the procedures, and one and six days later. The percentage of length reduction of spider veins, the target vessels, was analysed in digital photographs with Image J software. Ear thermographs were made with a thermocamera device and average temperatures were collected for analysis. Ear biopsies were obtained after six days. Endothelium average, inflammation, fibrosis, necrosis, skin burn, and vascular thrombosis were assessed using a specific score.

RESULTS

The mean vessel length reduction was 26% for Group 4, 2.4% for Group 3, .4% for Group 1, and 0 for Group 2, highlighting that in Group 4, the vessel lengths were significantly reduced compared with the other groups (p < .001). In the thermal analysis, in Group 3, the temperature was unchanged from the initial temperature and the central diameter vessel increased after six days, while, in Group 4, the temperature decreased and the vessels were not clearly detected, suggesting a reduction of the vessels and smaller infusion. Histology showed no difference among groups and one case of necrosis was found in Group 4.

CONCLUSIONS

PDT was associated with significantly more target vessel sclerosis than glucose injection and controls.

Quantificação do colágeno dérmico equino por duas técnicas morfométricas: contagem de pontos e segmentação de cor

RESUMO Os colágenos tipos I e III apresentam diferentes tonalidades de birrefringência em cortes histológicos corados com Picrosirius red e analisados em microscópio sob luz polarizada. Com base nessa propriedade, os colágenos podem ser quantificados por histomorfometria. Entretanto, são muitas as variáveis que podem afetar a distribuição das cores na imagem histológica, e a escolha adequada dos parâmetros de análise têm grande influência no resultado final. O objetivo deste trabalho foi comparar a quantificação histomorfométrica de colágeno em pele equina pela morfometria por contagem de pontos e pela segmentação de cor com diversas configurações, a fim de se determinar o melhor método de avaliação. Para a morfometria por contagem de pontos, foram utilizadas três gratículas diferentes (391, 588 e 792 pontos de interseções) e, para a segmentação de cor, seis combinações de hue e brightness no software ImageJ. Os valores foram submetidos ao teste de Friedman, seguido pelo teste de Tukey com 5% de significância. Os resultados demonstraram que a quantificação dos colágenos na gratícula de 792 pontos foi equivalente aos resultados da segmentação de cor com brightness de 1-255 e hue de 0-42 e 43-120 para os colágenos tipos I e III, respectivamente. Dessa forma, conclui-se que a análise automática da segmentação de cor, utilizando configuração adequada para brightness e hue, pode substituir a morfometria por contagem de pontos de forma confiável e segura.

Characterization of Collagen Fibers (I, III, IV) and Elastin of Normal and Neoplastic Canine Prostatic Tissues

This study aimed to investigate collagen (Coll-I, III, IV) and elastin in canine normal prostate and prostate cancer (PC) using Picrosirius red (PSR) and Immunohistochemical (IHC) analysis. Eight normal prostates and 10 PC from formalin-fixed, paraffin-embedded samples were used. Collagen fibers area was analyzed with ImageJ software. The distribution of Coll-I and Coll-III was approximately 80% around prostatic ducts and acini, 15% among smooth muscle, and 5% surrounding blood vessels, in both normal prostate and PC. There was a higher median area of Coll-III in PC when compared to normal prostatic tissue (p = 0.001 for PSR and p = 0.05 for IHC). Immunostaining for Coll-IV was observed in the basal membrane of prostate acini, smooth muscle, blood vessels, and nerve fibers of normal and PC samples. Although there was no difference in Coll-IV area between normal tissue and PC, tumors with Gleason score 10 showed absence of Coll-IV, when compared to scores 6 and 8 (p = 0.0095). Elastic fibers were found in the septa dividing the lobules and around the prostatic acini of normal samples and were statistically higher in PC compared to normal tissue (p = 0.00229). Investigation of ECM components brings new information and should be correlated with prognosis in future studies.

Surgical sponge associated with platelets rich plasma in skin mesh grafts and layer in rabbits (Oryctolagus cuniculus)

ABSTRACT The aim of this study was to evaluate of the efficacy of PRP employment associated with surgical sponges to improve the integration of the graft in the recipient bed. It was held at the Veterinary Hospital UNESP, Campus of Jaboticabal - SP, a study of 64 rabbits, divided into eight groups with eight animals. The groups were divided in control with saline solution 0,9%, control with PRP both without the sponge, surgical sponge with PRP, surgical sponge without PRP, and were used mesh and layer grafts in the respective groups. The data were submitted to statistical analysis (paired t-test, Kruskal-Wallis test, with subsequent use of the multiple comparison tests of Dunn, analysis of variance (F) test, Tukey test, P< 0.05). Edema and exudate with 3 and 3 and 7 days (P= 0,03 e P= 0,0049); coloring on the 14th day (P= 0,0001); cosmetic appearance on the 7th and 14th day (P= 0,0026 and P= 0,0001); mononuclear cells (P= 0,01) and polymorphonuclear (P= 0,01); fibroblast proliferation (P= 0,01); collagenous (P= 0,05); hemorrhage (P-007); necrosis and re-epithelialization (P= 0,2928 and P= 0,1). We concluded that the use of Platelet Rich Plasma Gel on skin grafts associated with a sponge as a compressive dressing promote the skin graft survival without a previous granulation tissue.

Evaluation of dermal collagen stained with picrosirius red and examined under polarized light microscopy

The special picrosirius red staining highlights the natural birefringence of collagen fibers when exposed to polarized light. The results from birefringence allow to evaluate the organization of the collagen fibers in the tissues. The authors intend to elucidate all steps to obtain and capture images of histological sections stained with picrosirius red and evaluated under polarized light microscopy, as well as possible artefacts that may occur.