Effect of estrogen depression on alveolar bone microarchitecture and periodontal ligament cells during orthodontic movement.

This study aimed to evaluate the effects of the estrogen depression during orthodontic tooth movement on alveolar bone microarchitecture and periodontal ligament. Female Wistar rats were divided into two groups, one consisting of non-ovariectomized animals subjected to orthodontic tooth movement, and one comprising ovariectomized animals subjected to orthodontic tooth movement. Micro-CT assessment of bone volume to total volume (BV/TV), total porosity, trabecular thickness (Tb.Th), trabecular number (Tb.N), and trabecular separation (Tb.Sp) in the alveolar bone of the orthodontically moved tooth was performed. Histomorphometric analyses were made in the periodontal ligament, and immunoexpression of RANK, RANKL, OPG, and TUNEL were quantified. Orthodontic tooth movement in the group of ovariectomized rats was faster than in non-ovariectomized animals. The alveolar bone area showed lower values of BV/TV and trabecular thickness, and higher bone porosity and trabeculae numbers in the ovariectomized rats. Histological analyses in the ovariectomized group revealed an increase in collagen fibers in the periodontal ligament. The apoptotic cell counts in the periodontal ligament were higher in the group of ovariectomized rats than in the sham-operated rats. Ovariectomy resulted in an increase in tooth movement and alteration of the alveolar bone microstructure in the first 7 day of orthodontic tooth movement, and in the presence of apoptotic cells in the periodontal ligament.

Liver fibrotic development is reduced through inflammation prevention by an adenosine derivative compound.

BACKGROUND: Liver fibrosis is a global health problem, and studying its development provides important information to address its treatment. Here, we characterized the effects of an adenosine compound (IFC-305) on preventing fibrosis and liver inflammation. METHODS: We studied the impact of IFC-305 on a carbon tetrachloride-induced liver fibrosis model in Wistar male rats at 4, 6, and 8 weeks. The effects were characterized by liver tissue histology, macrophages identification by flow cytometry with CD163+/CD11b/c+ antibodies, hepatic and plasmatic cytokine levels employing MILLIPLEX MAP and ELISA, Col1a1 and Il6 gene expression by RTqPCR, lipoperoxidation by TBARS reaction, and reactive oxygen species using 2'-7'dichlorofluorescin diacetate. RESULTS: CCl4-induced liver fibrosis and inflammation were significantly reduced in rats treated with IFC-305 at 6 and 8 weeks. In addition, we observed diminished expression of Col1a1; a decrease in the inflammatory cytokines IL-1ß, IL-6, MCP-1, TNF-α, and IL-4 a; reduction in inflammatory macrophages; inhibition of lipoperoxidation; and ROS production in Kupffer cells. CONCLUSION: This study showed that IFC-305 can inhibit liver fibrosis establishment by regulating the immune response during CCl4-induced damage. The immunomodulatory action of IFC-305 supports its use as a potential therapeutic strategy for preventing liver fibrosis.

Cardioprotective Effects of the 4-Week Aerobic Running Exercises Before Treatment with Doxorubicin in Rats.

Doxorubicin is associated with cardiotoxicity, and physical exercise seeks to minimize the toxic effects of doxorubicin through physiological cardiac remodeling, as well as the reduction of oxidative stress, evidenced by previous studies. This study aimed to analyze whether running training before treatment with doxorubicin influences tolerance to physical exertion and cardiotoxicity. Thirty-nine male Wistar rats, aged 90 days and weighing between 250 and 300 g, were divided into 4 groups: Control (C), Doxorubicin (D), Trained (T), and Trained + Doxorubicin (TD). Animals in groups T and DT were submitted to treadmill running for 3 weeks, 5 times a week at 18 m/min for 20-30 min before treatment with doxorubicin. Animals in groups D and DT received intraperitoneal injections of doxorubicin hydrochloride three times a week for two weeks, reaching a total cumulative dose of 7.50 mg/kg. Our results show an increase in total collagen fibers in the D group (p = 0.01), but no increase in the TD group, in addition to the attenuation of the number of cardiac mast cells in the animals in the TD group (p = 0.05). The animals in the TD group showed maintenance of tolerance to exertion compared to group D. Therefore, running training attenuated the cardiac damage caused by the treatment with doxorubicin, in addition to maintaining the tolerance to exertion in the rats.

Effects of different subcutaneous sites on heterotopic autotransplantation of canine ovarian tissue.

Ovarian tissue transplantation makes it possible to restore fertility; however, the success of this technique depends on the transplant region used. Therefore, this study aimed to evaluate the effect of two subcutaneous regions on canine ovarian transplantation, pinna (Pi) and neck (Ne), for 7 and 15 days. Ovaries collected by ovariosalpingohysterectomy were fragmented using a punch device. Fresh fragments were fixed, and the others were immediately grafted onto the animal itself in the Pi and Ne regions for 7 and 15 days. Recovered fragments were evaluated for histology (morphology, development and stromal density), picrosirius (collagen fibers), and immunohistochemistry (fibrosis and cell proliferation). The results showed that follicular normality rates were lower in Pi-7 (78%) vs. control (90%) and Pi-15 (86%), similar in Ne-7 (92%) and superior in Ne-15 (97%) compared to the control, with the effect of the region Ne (94%) superior (P < 0.05) to Pi (82%). Stromal density reduced in both regions vs. control but was similar within 15 days. Fragments from both regions showed higher fibronectin labeling and deposition of type I and lower type III collagen fibers (P < 0.05) vs. control. Proliferation rates in Ne-7 were higher (P < 0.05) than in control, and Pi-15 was higher (P < 0.05) than Ne-15. In conclusion, the pinna may be a region with greater potential than the neck after a 15-day autotransplantation of canine ovarian tissue.

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.

Heterotopic ovarian allotransplantation in goats: Preantral follicle viability and tissue remodeling.

An appropriate implantation site favors angiogenesis and avoids ovarian tissue damage after tissue grafting. The objective of this study was to evaluate the effects of intramuscular (IM) and subcutaneous (SC) sites for ovarian grafts in goats by evaluating follicular morphology and activation, preantral follicle and stromal cell densities, tissue DNA fragmentation, collagen types I and III depositions, and graft revascularizations. Ovarian cortical tissue was transplanted in IM or SC sites and recovered 7 or 15 days post-transplantation. There was a greater percentage of developing follicles and lesser follicular and stromal cell densities in all grafted tissues as compared to ovarian tissues of the control group. The stromal cell density and percentage of normal follicles were positively associated. At 15 days post-transplantation, tissues at the SC and IM sites had similar amounts of DNA fragmentation and type III collagen content. In contrast, tissues at the SC, as compared with IM site, had greater abundances of collagen type I. Furthermore, there was a positive association between collagen type I and percentage of morphologically normal follicles post-transplantation. In addition to a marked decrease in follicular density 15 days post-transplantation in ovarian grafts at the SC and IM sites, low percentages of normal follicles and follicular activation were observed similarly in both transplantation sites. There were also positive associations of stromal cell density and abundance of type I collagen fibers with the percentage of intact follicles in grafted ovarian tissues.

Chronic cachaça consumption affects the structure of tibial bone by decreasing bone density and density of mature collagen fibers in middle-aged Wistar rats.

Several studies have demonstrated that alcohol consumption can decrease bone density and alter its structure. However, most of the studies did not investigate the effects of specific alcoholic beverages. This study determined the effects of chronic consumption of cachaça (a Brazilian beverage containing alcohol) on body weight (BW), tibia bone density and on the tibia collagen density in middle-aged Wistar rats. Rats with 9 months old were submitted for 100 days, to a liquid diet of cachaça diluted in water with a progressive and controlled concentration (10°GL, 15°GL, 20°GL, 25°GL, and 30°GL). Chronic cachaça intake produced a significant decrease in BW and altered bone remodeling, decreasing trabecular bone density. In chronic cachaça-treated group (CT), the production of collagen fibers in bone tissue has predominantly green birefringence. It appears that they are immature fibers that do not exist in the control group, in which there are standard predominantly yellowish mature fibers. In conclusion, chronic cachaça consumption affects the structure of the tibial bone of middle-aged rats by decreasing the bone density and reducing the density of mature collagen fibers.

Short time insulin treatment post burn improves elastic-collagen rearrangement and reepithelization.

Extensive burn may cause acute resistance to insulin, which accentuates hypermetabolism, impairs glucose metabolism, immune dysfunction and risks of sepsis. To minimize these effects, insulin is used as a treatment. The purpose was to analyze the collagen-elastic arrangement effects of insulin on the burned skin. Wistar rats were assigned in groups: control (C); control with insulin (C + I); scald burn injury (SBI); and SBI with insulin (SBI+ I). SBI were submitted to 45% total body surface area burn and the insulin-treated groups received insulin (5 UI/Kg/day) for 4 or 14 days (d). Insulin levels, glucose tolerance test and HOMA index were determined. The skin sections were analyzed for histophatological and morphoquantitative data. Histopathological findings showed increased reepithelization of SBI+ I and formation of a new muscle layer after 14 days. In the collagen-elastic arrangement, insulin for 4 days increased the volume fraction (Vv) of thin collagen and elastic fibers. After 14 days, independently of injury, insulin decreased the elastic fibers. Insulin was able to reverse damages in the collagen-elastic rearrangement and stimulate reepithelization after 4 days. Untreated scald-burned animals showed higher Vv of thick collagen after 4 days, while those treated had a higher Vv of thin collagen. The Vv of elastic fibers was increased in SBI+ I for 4 days. In conclusion, insulin treatment was able to stimulate reepithelization. It also reversed the damages to the collagen-elastic arrangement in the scald-burned group, improving the organization of thin collagen and increasing the Vv of elastic fibers in the injured group treated with insulin for a short time, that is, for 4 days.

Swimming training potentiates the recovery of femoral neck strength in young diabetic rats under insulin therapy

OBJECTIVE: To test whether swimming training benefits femoral neck strength in young diabetic rats under insulin therapy. METHODS: A total of 60 male Wistar rats (age: 40 days) were divided equally into the following six groups: control sedentary, control exercise, diabetic sedentary, diabetic exercise, diabetic sedentary plus insulin and diabetic exercise plus insulin. Diabetes was induced with a unique intraperitoneal injection (60 mg/kg body weight) of streptozotocin. Seven days after the injection and after 12 hours of fasting, the animals with blood glucose levels ≥300 mg/dL were considered diabetic. Seven days after the induction of diabetes, the animals in the exercise groups were subjected to progressive swimming training (final week: 90 min/day; 5 days/week; 5% load) for eight weeks. The animals in the insulin groups received a daily dose of insulin (2-4 U/day) for the same period. RESULTS: Severe streptozotocin-induced diabetes reduced the structural properties of the femoral neck (trabecular bone volume, trabecular thickness and collagen fiber content). The femoral neck mechanical properties (maximum load and tenacity) were also impaired in the diabetic rats. Insulin therapy partially reversed the damage induced by diabetes on the structural properties of the bone and mitigated the reductions in the mechanical properties of the bone. The combination of therapies further increased the femoral neck trabecular bone volume (∼30%), trabecular thickness (∼24%), collagen type I (∼19%) and type III (∼13%) fiber contents, maximum load (∼25%) and tenacity (∼14%). CONCLUSIONS: Eight weeks of swimming training potentiates the recovery of femoral neck strength in young rats with severe streptozotocin-induced diabetes under insulin therapy.

Morphological analysis of the elastic and collagen fibers in the ram penis / Análise morfológica de fibras elásticas e colágenas no pênis de ovinos

The penis represents the organ of the male's copulation. It is essential to know the reproductive biology and the morphology of the reproductive organs to increase animal production. In order to contribute to this knowledge and provides information on the ram reproductive morphology, the purpose of this work was to describe the distribution, based on light microscopy, of the collagen and elastic fibers in the ram penis. For that, were collected transverse fragments of the penis (root, sigmoid flexure, body and glans) of seven rams. The specimens were fixed in paraformaldehyde for 24h and destined for the histological routine. The extracellular matrix of the ram penis was composed of collagen and elastic fibers. The penis was enveloped by the tunica albuginea, consisting essentially of collagen fibers, which were arranged in two layers: an outer longitudinal and an inner circular. This tunic emitted septa that penetrated the corpus cavernosum. The elastic fibers appeared transversely and longitudinally in the corpus cavernosum, corpus spongiosum, and next to the neurovascular bundle of the penis. This structure was not different to that reported for other domestic ruminants such as cattle and buffaloes.(AU)

O pênis representa o órgão da cópula do macho. É fundamental que se conheça a biologia reprodutiva e a morfologia dos órgãos reprodutores para o incremento da produção animal. Com o objetivo de contribuir para este conhecimento e fornecer informações sobre a morfologia reprodutiva de ovinos, o propósito deste trabalho foi descrever a distribuição, com base na microscopia de luz, das fibras colágenas e elásticas no pênis de ovinos. Para tanto, foram coletados fragmentos transversais do pênis (raiz, flexura sigmoide, corpo e glande) de sete ovinos. Os exemplares foram fixados em paraformaldeído por 24h e destinados à rotina histológica. A matriz extracelular do pênis de ovinos estava constituída por fibras colágenas e elásticas. O pênis estava envolvido pela túnica albugínea, formada essencialmente por fibras colágenas, que estavam arranjadas em duas camadas: longitudinal externa e circular interna. Esta túnica emitiu septos que penetraram no corpo cavernoso. As fibras elásticas apareceram de modo transversal e longitudinal nos corpos cavernoso e esponjoso e junto ao feixe vásculo-nervoso do pênis de ovinos. Esta estrutura mostrou-se similar ao encontrado em outros ruminantes domésticos como bovinos e bubalinos.(AU)

Morphological analysis of the elastic and collagen fibers in the ram penis / Análise morfológica de fibras elásticas e colágenas no pênis de ovinos

The penis represents the organ of the male's copulation. It is essential to know the reproductive biology and the morphology of the reproductive organs to increase animal production. In order to contribute to this knowledge and provides information on the ram reproductive morphology, the purpose of this work was to describe the distribution, based on light microscopy, of the collagen and elastic fibers in the ram penis. For that, were collected transverse fragments of the penis (root, sigmoid flexure, body and glans) of seven rams. The specimens were fixed in paraformaldehyde for 24h and destined for the histological routine. The extracellular matrix of the ram penis was composed of collagen and elastic fibers. The penis was enveloped by the tunica albuginea, consisting essentially of collagen fibers, which were arranged in two layers: an outer longitudinal and an inner circular. This tunic emitted septa that penetrated the corpus cavernosum. The elastic fibers appeared transversely and longitudinally in the corpus cavernosum, corpus spongiosum, and next to the neurovascular bundle of the penis. This structure was not different to that reported for other domestic ruminants such as cattle and buffaloes.(AU)

O pênis representa o órgão da cópula do macho. É fundamental que se conheça a biologia reprodutiva e a morfologia dos órgãos reprodutores para o incremento da produção animal. Com o objetivo de contribuir para este conhecimento e fornecer informações sobre a morfologia reprodutiva de ovinos, o propósito deste trabalho foi descrever a distribuição, com base na microscopia de luz, das fibras colágenas e elásticas no pênis de ovinos. Para tanto, foram coletados fragmentos transversais do pênis (raiz, flexura sigmoide, corpo e glande) de sete ovinos. Os exemplares foram fixados em paraformaldeído por 24h e destinados à rotina histológica. A matriz extracelular do pênis de ovinos estava constituída por fibras colágenas e elásticas. O pênis estava envolvido pela túnica albugínea, formada essencialmente por fibras colágenas, que estavam arranjadas em duas camadas: longitudinal externa e circular interna. Esta túnica emitiu septos que penetraram no corpo cavernoso. As fibras elásticas apareceram de modo transversal e longitudinal nos corpos cavernoso e esponjoso e junto ao feixe vásculo-nervoso do pênis de ovinos. Esta estrutura mostrou-se similar ao encontrado em outros ruminantes domésticos como bovinos e bubalinos.(AU)

Collagen analysis by second-harmonic generation microscopy predicts outcome of luminal breast cancer.

Second-harmonic generation microscopy represents an important tool to evaluate extracellular matrix collagen structure, which undergoes changes during cancer progression. Thus, it is potentially relevant to assess breast cancer development. We propose the use of second-harmonic generation images of tumor stroma selected on hematoxylin and eosin-stained slides to evaluate the prognostic value of collagen fibers analyses in peri and intratumoral areas in patients diagnosed with invasive ductal breast carcinoma. Quantitative analyses of collagen parameters were performed using ImageJ software. These parameters presented significantly higher values in peri than in intratumoral areas. Higher intratumoral collagen uniformity was associated with high pathological stages and with the presence of axillary lymph node metastasis. In patients with immunohistochemistry-based luminal subtype, higher intratumoral collagen uniformity and quantity were independently associated with poorer relapse-free and overall survival, respectively. A multivariate response recursive partitioning model determined 12.857 and 11.894 as the best cut-offs for intratumoral collagen quantity and uniformity, respectively. These values have shown high sensitivity and specificity to differentiate distinct outcomes. Values of intratumoral collagen quantity and uniformity exceeding the cut-offs were strongly associated with poorer relapse-free and overall survival. Our findings support a promising prognostic value of quantitative evaluation of intratumoral collagen by second-harmonic generation imaging mainly in the luminal subtype breast cancer.

Quantitative evaluation of collagen and elastic fibers after intense pulsed light treatment of mouse skin.

BACKGROUND AND OBJECTIVE: The aging of human skin includes intrinsic aging and photo-aging, which are characterized by a decrease in collagen and the deposition of abnormal elastic fibers. Intense pulsed light (IPL) sources are widely used in medicine to treat various cosmetic problems, including photo-damaged skin. Few studies have examined the microscopic changes produced by IPL. The objective of this study was to quantitatively evaluate the effects of IPL on collagen and elastic fibers in mice. MATERIALS AND METHODS: Forty female BALB/c mice were divided into four subgroups. Group 1 was the control group (n = 10), and groups 2, 3, and 4 were treatment groups (n = 10 in each group). Group 2 received one treatment, group 3 received two treatments, and group 4 received three treatments every 2 weeks. Skin tissue was obtained from irradiated areas 24 hours after the last treatment in each mouse. Collagen fibers were identified using the picrosirius red method. Elastic fibers were marked by Weigert-oxone stain. All samples were analyzed and quantified by a light microscope using analyzer system images. RESULTS: Group 4, which received three IPL treatments, showed significant quantitative increases in both collagen fibers (P < 0.05) and elastic fibers (P < 0.01). Collagen fibers demonstrated a better parallel distribution in relation to the epidermis. CONCLUSION: IPL treatment significantly increased the number of collagen and elastic fibers within the dermis and improved the parallel distribution of collagen fibers in relation to the epidermis. These results were evident after three IPL treatments. Lasers Surg. Med. © 2018 Wiley Periodicals, Inc.

Quantitative evaluation of collagen and elastic fibers after intense pulsed light treatment of mouse skin

Background and Objective The aging of human skin includes intrinsic aging and photo-aging, which are characterized by a decrease in collagen and the deposition of abnormal elastic fibers. Intense pulsed light (IPL) sources are widely used in medicine to treat various cosmetic problems, including photo-damaged skin. Few studies have examined the microscopic changes produced by IPL. The objective of this study was to quantitatively evaluate the effects of IPL on collagen and elastic fibers in mice. Materials and Methods Forty female BALB/c mice were divided into four subgroups. Group 1 was the control group (n?=?10), and groups 2, 3, and 4 were treatment groups (n?=?10 in each group). Group 2 received one treatment, group 3 received two treatments, and group 4 received three treatments every 2 weeks. Skin tissue was obtained from irradiated areas 24 hours after the last treatment in each mouse. Collagen fibers were identified using the picrosirius red method. Elastic fibers were marked by Weigert-oxone stain. All samples were analyzed and quantified by a light microscope using analyzer system images. Results Group 4, which received three IPL treatments, showed significant quantitative increases in both collagen fibers (P<0.05) and elastic fibers (P<0.01). Collagen fibers demonstrated a better parallel distribution in relation to the epidermis. Conclusion IPL treatment significantly increased the number of collagen and elastic fibers within the dermis and improved the parallel distribution of collagen fibers in relation to the epidermis. These results were evident after three IPL treatments.

Avaliação das fibras colágenas de feridas dérmicas de coelhos tratadas com diferentes fontes de plasma rico em plaquetas / Evaluation of collagen in dermal wounds of rabbits treated with different sources of platelet-rich plasma

Para comparar a regeneração tecidual de feridas dérmicas em coelhos tratados e não tratados, de forma seriada, com diferentes fontes de plasma rico em plaquetas (PRP) gel, biópsias dérmicas foram feitas na região dorsal, com auxílio de um punch de 8mm, em que o lado direito foi tratado com NaCl 0,9%® e o lado esquerdo recebeu aplicação de diferentes fontes de PRPs (autóloga, heteróloga e homóloga), nos dias zero, três, sete, 10, 14, tendo sido acompanhadas durante 17 dias. Ao final do 17º dia, foi realizada avaliação histopatológica das feridas. Do total de 24 animais, seis coelhos (três machos e três fêmeas) foram utilizados somente como doadores para obtenção do PRP homólogo gel. Um cão adulto, saudável, foi utilizado como doador durante o experimento para o preparo do PRP gel do grupo heterólogo. As médias das fibras dos grupos autólogo e homólogo foram muito semelhantes (75,0±13,7 e 73,1±10,2, respectivamente), quando comparadas às médias obtidas no grupo controle (71,5±10,8). Já as fibras colágenas do grupo heterólogo foram inferiores (P<0,05) às dos demais grupos (59,4±11,3). Conclui-se que a fonte heteróloga produz fibras colágenas menos organizadas e menos homogêneas, sendo o último recurso a ser utilizado para promover uma cicatrização de boa qualidade.(AU)

In order to compare the tissue regeneration of dermal wounds in treated and untreated rabbits serially with different sources of platelet rich plasma (PRP) gel, dermal biopsies were made in the dorsal region with the aid of an 8mm punch. The right side was treated with 0.9% NaCl and, on the left side, the different sources of PRPs (autologous, heterologous and homologous) on days 0, 3, 7, 10, 14 were applied and monitored for 17 days. At the end of the 17th day, histopathological evaluation of the wounds was performed. From the total of 24 animals, six rabbits (3 males and 3 females) were used only as donors to obtain the homologous PRP gel. A healthy, adult dog was used as a donor during the experiment to prepare the PRP gel from the heterologous group. The mean values of the fibers of the autologous and homologous groups were very similar (75.0±13.7 and 73.1±10.2, respectively), when compared to the means obtained in the control group (71.5±10.8). The collagen fibers of the heterologous group were inferior (P<0.05) to the other groups (59.4±11.3). It is concluded that the heterologous source produces less organized and homogeneous collagen fibers and should be the last resource to be used in order to promote good quality healing.(AU)

Avaliação das fibras colágenas de feridas dérmicas de coelhos tratadas com diferentes fontes de plasma rico em plaquetas / Evaluation of collagen in dermal wounds of rabbits treated with different sources of platelet-rich plasma

Para comparar a regeneração tecidual de feridas dérmicas em coelhos tratados e não tratados, de forma seriada, com diferentes fontes de plasma rico em plaquetas (PRP) gel, biópsias dérmicas foram feitas na região dorsal, com auxílio de um punch de 8mm, em que o lado direito foi tratado com NaCl 0,9%® e o lado esquerdo recebeu aplicação de diferentes fontes de PRPs (autóloga, heteróloga e homóloga), nos dias zero, três, sete, 10, 14, tendo sido acompanhadas durante 17 dias. Ao final do 17º dia, foi realizada avaliação histopatológica das feridas. Do total de 24 animais, seis coelhos (três machos e três fêmeas) foram utilizados somente como doadores para obtenção do PRP homólogo gel. Um cão adulto, saudável, foi utilizado como doador durante o experimento para o preparo do PRP gel do grupo heterólogo. As médias das fibras dos grupos autólogo e homólogo foram muito semelhantes (75,0±13,7 e 73,1±10,2, respectivamente), quando comparadas às médias obtidas no grupo controle (71,5±10,8). Já as fibras colágenas do grupo heterólogo foram inferiores (P<0,05) às dos demais grupos (59,4±11,3). Conclui-se que a fonte heteróloga produz fibras colágenas menos organizadas e menos homogêneas, sendo o último recurso a ser utilizado para promover uma cicatrização de boa qualidade.(AU)

In order to compare the tissue regeneration of dermal wounds in treated and untreated rabbits serially with different sources of platelet rich plasma (PRP) gel, dermal biopsies were made in the dorsal region with the aid of an 8mm punch. The right side was treated with 0.9% NaCl and, on the left side, the different sources of PRPs (autologous, heterologous and homologous) on days 0, 3, 7, 10, 14 were applied and monitored for 17 days. At the end of the 17th day, histopathological evaluation of the wounds was performed. From the total of 24 animals, six rabbits (3 males and 3 females) were used only as donors to obtain the homologous PRP gel. A healthy, adult dog was used as a donor during the experiment to prepare the PRP gel from the heterologous group. The mean values of the fibers of the autologous and homologous groups were very similar (75.0±13.7 and 73.1±10.2, respectively), when compared to the means obtained in the control group (71.5±10.8). The collagen fibers of the heterologous group were inferior (P<0.05) to the other groups (59.4±11.3). It is concluded that the heterologous source produces less organized and homogeneous collagen fibers and should be the last resource to be used in order to promote good quality healing.(AU)

Idiopathic atrophoderma of Pasini and Pierini: A case study of collagen and elastin texture by multiphoton microscopy.

BACKGROUND: The diagnosis of idiopathic atrophoderma of Pasini and Pierini (IAPP) relies on typical clinical features, particularly distinctive pigmented ovular/round depressed plaques. Histologic examination often reveals no obvious changes, but patterns of collagen distribution, using multiphoton imaging and second harmonic generation can help track hidden details of tissue organization contributing to atrophy. OBJECTIVE: To identify histologic features that distinguish IAPP from unaffected skin. METHODS: Eleven patients were included for conventional analyses. Masson trichrome- and Unna-Tanzer orcein-stained sections were evaluated using automated morphometry. Hematoxylin-eosin-stained sections were analyzed by multiphoton imaging using 2-photon excited fluorescence and second harmonic generation. RESULTS: No abnormalities were found under light microscopy or by automated quantification. Multiphoton imaging revealed no difference in optical density of either collagen or elastic fibers in lesioned and unaffected skin; however, horizontal collagen fiber organization in lesion specimens increased toward the lower dermis, whereas elastic fibers featured greater disorganization within the upper dermis. LIMITATIONS: The low number of patients evaluated. CONCLUSION: The atrophic appearance of IAPP lesions reflects changes in organization, but not in collagen and elastic tissue content. Minute organizational differences that are imperceptible to the experienced pathologist and undetectable by automated analyses were revealed by multiphoton analyses, particularly second harmonic generation, in association with texture analyses.

Experimental tooth movement and photobiomodulation on bone remodeling in rats.

Photobiomodulation (PBM) is a therapy induced by a specific type of laser that affects biologic systems through non-thermal ways. The study of its basic mechanism has gained interest since little is known about the causes of the different effects of this treatment. In the present study, we investigated the action of the PBM application rate changes in the peri-implant tissues in rats subjected to tooth movement in different periods. Wistar rats (±250 g) received an apparatus in the region of the central incisors superiors tightly (70 g) or not, and they were also subjected to one or three PBM sessions. After 7 or 14 days, the rats were subjected to euthanasia and the jaws were dissected and processed for histology. For analysis, serial sections were made that were stained by Picrosirius Red for analysis of collagen fibers, Masson's trichrome for newly formed bone scan, and Hematoxylin-Eosin for quantification of osteoblasts. PBM applied in one or three sessions increased the population of osteoblasts. Still, the application of three sessions of PBM increased the density of collagen fibers and new bone formation compared to the controls. An increase was observed in the interincisal distance in irradiated groups with three PBM sessions and the application of force for both 7 or 14 days. These findings suggest that PBM can contribute positively to the orthodontic movement. So the laser therapy can be used as an adjunct procedure to be performed concurrently for orthodontic treatment in the dental clinic.

Effects of aging on the architecture of the ileocecal junction in rats.

AIM: To evaluate the structural organization of the elastic and collagen fibers in the region of the ileocecal transition in 30 young and old male Wistar rats. METHODS: Histology, immunohistochemistry (IHC), transmission electron microscopy and scanning electron microscopy were employed in this study. The results demonstrated that there was a demarcation of the ileocecal region between the ileum and the cecum in both groups. RESULTS: The connective tissue fibers had different distribution patterns in the two groups. IHC revealed the presence of nitric oxide synthase, enteric neurons and smooth muscle fibers in the ileocecal junctions (ICJs) of both groups. Compared to the young group, the elderly group exhibited an increase in collagen type I fibers, a decrease in collagen type III fibers, a decreased linear density of oxytalan elastic fibers, and a greater linear density of elaunin and mature elastic fibers. CONCLUSION: The results revealed changes in the patterns of distribution of collagen and elastic fibers that may lead to a possible decrease in ICJ functionality.

Microanatomy of the lateral femoral cutaneous nerve in relation to inguinal ligament and its clinical importance / Microanatomia do nervo cutâneo femoral lateral em relação ao ligamento inguinal e sua importância clínica

BACKGROUND: A better knowledge of the composition and properties of connective tissue related to the Lateral Femoral Cutaneous Nerve (LFCN) and to the Inguinal Ligament may be important to understand the diagnosis and treatment applicable to injuries such as meralgia paresthetica. OBJECTIVE: To determine the relative amounts of the non-fascicular components in the following areas: (i) proximal to the inguinal ligament [LFCN-1], (ii) deep to the inguinal ligament [LFCN-2], or (iii) distal to LFCN-2 [LFCN-3]. These amounts were discriminated as adipose [FAT] and non-adipose (connective) [NON-FAT] tissues. METHOD: Samples of LFCN-1, LFCN-2 and LFCN-3 from 21 human cadaveric samples were used. Paraffin sections of these structures were processed by Masson's trichrome stain for connective tissue. The number of fascicles was counted in each of these structures; FAT and NON-FAT areas were determined in the non-fascicular areas of the structures. RESULTS: There were more fascicles in LFCN-3 vs. LFCN-1 or LFCN-2; there was more NON-FAT vs. FAT in LFCN-2 vs. LFCN-1 and LFCN-3; inversely, there was more FAT vs. NON-FAT in LFCN-3 vs. LFCN-1 and LFCN-2. All of these comparisons were statistically significant. CONCLUSION: The presence of a higher content of NON-FAT in LFCN-2 and FAT in LFCN-3 may help to explain meralgia paresthetica resulting from compression or focal entrapment of the Lateral Femoral Cutaneous Nerve as it passes deep relative to the inguinal ligament.

TEMA: Um melhor conhecimento da composição e propriedades do tecido conjuntivo relacionadas ao Nervo Cutâneo Femoral Lateral (NCFL) e ao Ligamento Inguinal pode ser importante para compreender o diagnóstico e o tratamento aplicável a lesões como a meralgia parestética. OBJETIVO: Determinar as quantidades relativas dos componentes não-fasciculares nas seguintes áreas: (i) proximal ao ligamento inguinal [NCFL-1], (ii) em profundidade ao ligamento inguinal [NCFL-2], ou (iii) distal a NCFL-2 [NCFL-3]. Esses valores foram discriminados como tecido conjuntivo adiposo [FAT] ou não-adiposo [NON_FAT]. MÉTODO: Foram utilizadas amostras de NCFL-1, NCFL-2 e NCFL-3 a partir de 21 amostras de cadáveres humanos. As secções em parafina destas estruturas foram processadas por coloração Masson para tecido conjuntivo. O número de fascículos foi contado em cada uma destas estruturas; áreas de gordura e sem gordura foram determinadas nas áreas não-fasciculares das estruturas. RESULTADOS: Foram contados mais fascículos em NCFL-3 vs. NCFL-1 ou NCFL-2; havia mais NON-FAT vs. FAT em NCFL-2 vs. NCFL-1 e NCFL-3; inversamente, houve mais FAT vs. NON-FAT em NCFL-3 vs. NCFL-1 e NCFL-2. Todas estas comparações foram estatisticamente significativas. CONCLUSÃO: A presença de um maior teor de NONFAT em NCFL-2 e FAT em NCFL-3 pode ajudar a explicar o aparecimento de paresthetica meralgia resultante da compressão ou encarceramento focal do Nervo Cutâneo Femoral Lateral que passa profundamente ao ligamento inguinal.