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Extracellular matrix (ECM) proteins in the mammary gland provide structure and regulate its development and homeostasis. Alterations in its structure can regulate and support pathogenesis, like breast tumors. Aiming to identify the health and tumoral canine mammary ECM scaffold protein profile by immunohistochemistry, the decellularization process was carried out to remove the cellular content. Additionally, it was verified the influence of health and tumoral ECM on the attachment of health and tumoral cells. The types I, III, IV, and V structural collagens were scarce in the mammary tumor, and ECM fibers were disorganized. Vimentin and CD44 were more common in mammary tumor stroma, suggesting a role in cell migration that results in tumor progression. Elastin, fibronectin, laminin, vitronectin, and osteopontin were similarly detected under healthy and tumor conditions, providing the attachment of normal cells in healthy ECM, while tumoral cells were able to attach in tumoral ECM. The protein pattern demonstrates ECM alteration in canine mammary tumorigenesis, presenting new knowledge on mammary tumor ECM microenvironment.

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OBJECTIVE: To evaluate the effect of several final irrigation protocols on radicular dentin microhardness, biochemical composition, and DMP1-CT expression. MATERIALS AND METHODS: A total of 140 single-rooted human teeth were prepared with WaveOne Gold files and randomly distributed into 7 groups (n = 20) according to the final irrigation protocol: distilled water (DW); sodium hypochlorite-EDTA (NaOCl-EDTA); EDTA (EDTA); EDTA-NaOCl (EDTA-NaOCl); EDTA-chlorhexidine (EDTA-CHX); passive ultrasonic irrigation (PUI:NaOCl-EDTA); and PUI:NaOCl-EDTA-NaOCl. Dentin microhardness (n = 10) was evaluated in the root canal lumen using Vickers hardness tester. Immunohistochemical analysis (n = 5) was used to evaluate DMP1-CT expression. Dentin ultrastructure and biochemical composition were evaluated by using Raman and energy dispersive X-ray analysis (EDAX) (n = 5) with a scanning electron microscope (SEM). Analysis of variance (ANOVA) and Tukey test were performed (p˂0.05). RESULTS: Raman spectra of the organic content and DMP1-CT expression were lower at the lumen canal in EDTA-NaOCl, PUI:NaOCl-EDTA, and PUI:NaOCl-EDTA-NaOCl when compared to control (p < 0.05). EDAX showed reduced values for calcium and phosphorus in EDTA-NaOCl, PUI:NaOCl-EDTA, and PUI:NaOCl-EDTA-NaOCl. SEM microphotography's showed completely cleaned dentin, permeable tubules, and dentin erosion, mainly when PUI was used. NaOCl-EDTA presented significantly higher microhardness values than PUI:NaOCl-EDTA-NaOCl (p < 0.05). PUI:NaOCl-EDTA-NaOCl exhibited the lowest Vickers hardness values of all groups. CONCLUSION: The final irrigation protocols that used a final rinse with NaOCl and PUI showed a detrimental effect on radicular dentin DMP1-CT expression, biochemical composition, and microhardness. CLINICAL RELEVANCE: The adequate irrigation protocol could be advantageous to preserve the radicular dentin ultrastructure, promote adequate adhesion, and sustain favorable conditions for biomineralization and regeneration.

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The biomineralisation of radicular dentin involves complex molecular signalling. Providing evidence of protein binding sites for calcium ions and mineral precipitation is essential for a better understanding of the remineralisation process. This study aimed to evaluate the functional relationship of metalloproteinases (MMPs) and non-collagenous proteins (NCPs) with mineral initiation and maturation during the biomineralisation of radicular dentin. A standardized demineralisation procedure was performed to radicular dentin slices. Samples were remineralised in a PBS-bioactive material system for different periods of time. Assessments of ion exchange, Raman analysis, and energy dispersive X-ray analysis (EDAX) with a scanning electron microscope (SEM) were used to evaluate the remineralisation process. Immunohistochemistry and zymography were performed to analyse NCPs and MMPs expression. SEM evaluation showed that the mineral nucleation and growth occurs, exclusively, on the demineralised radicular dentin surface. Raman analysis of remineralised dentin showed intense peaks at 955 and 1063 cm-1, which can be attributed to carbonate apatite formation. Immunohistochemistry of demineralised samples revealed the presence of DMP1-CT, mainly in intratubular dentin, whereas DSPP in intratubular and intertubular dentin. DMP1-CT and DSPP binding sites control carbonate apatite nucleation and maturation guiding the remineralisation of radicular dentin.

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BACKGROUND: External apical root resorption as a consequence of orthodontic treatment is an inflammatory pathological process that results in permanent loss of tooth structure from the root apex. OBJECTIVES: This study aimed to investigate the diagnostic potential of human dentine fractions and salivary IgG in external apical root resorption. PATIENTS AND METHODS: Saliva samples were collected from 10 patients before (T0) and after 3 (T3), 6 (T6) and 12 (T12) months of orthodontic treatment. The total dentinal extract, obtained from human third molars, was fractioned by gel filtration chromatography in three fractions denominated FI, FII and FIII. The root resorption analysis of the upper central incisors was performed by digital image subtraction method. Reactivity of salivary IgG to antigenic fractions of dentine was determined by enzyme-linked immunosorbent assay (Elisa). RESULTS: Regardless of treatment, FI dentin fraction with high MM (<300kDa) was the one that presented highest reactivity with salivary IgG. However, it was found higher salivary IgG reactivity for FII (69 to 45 kilodalton [kDa]) as compared to FIII (<45kDa) at (T6) and (T12), (P<0.05), the same periods in that the root resorptions were detected. CONCLUSION: Our results suggest that FII human dentine fraction and salivary IgG have potential to be used in diagnosis and monitoring of external apical root resorption. The development of a practical and accessible biochemical test using saliva and FII dentine fraction may help in the prevention of severe root resorption.

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In recent years, the scientific community has undertaken research on plant extracts, searching for compounds with pharmacological activities that can be used in diverse fields of medicine. Calendula officinalis L. is known to have antioxidant, anti-inflammatory, antibacterial, and wound healing properties when used to treat skin burns. Therefore, the purpose of this study was to analyze the effects of C. officinalis on the initial phase of Achilles tendon healing. Wistar rats were separated in three groups: Calendula (Cal)-rats with a transected tendon were treated with topical applications of C. officinalis cream and then euthanized 7 days after injury; Control (C)-rats were treated with only vehicle after transection; and Normal (N)-rats without tenotomy. Higher concentrations of hydroxyproline (an indicator of total collagen) and non-collagenous proteins were observed in the Cal group in relation to the C group. Zymography showed no difference in the amount of the isoforms of metalloproteinase-2 and of metalloproteinase-9, between C and Cal groups. Polarization microscopy images analysis showed that the Cal group presented a slightly higher birefringence compared with the C group. In sections of tendons stained with toluidine blue, the transected groups presented higher metachromasy as compared with the N group. Immunocytochemistry analysis for chondroitin-6-sulfate showed no difference between the C and Cal groups. In conclusion, the topical application of C. officinalis after tendon transection increases the concentrations of collagen and non-collagenous proteins, as well as the collagen organization in the initial phase of healing.

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Although several treatments for tendon lesions have been proposed, successful tendon repair remains a great challenge for orthopedics, especially considering the high incidence of re-rupture of injured tendons. Our aim was to evaluate the pharmacological potential of Aloe vera on the content and arrangement of glycosaminoglycans (GAGs) during tendon healing, which was based on the effectiveness of A. vera on collagen organization previously observed by our group. In rats, a partial calcaneal tendon transection was performed with subsequent topical A. vera application at the injury site. The tendons were treated with A. vera ointment for 7 days and excised on the 7(th) , 14(th) , or 21(st) day post-surgery. Control rats received ointment without A. vera. A higher content of GAGs and a lower amount of dermatan sulfate were detected in the A. vera-treated group on the 14(th) day compared with the control. Also at 14 days post-surgery, a lower dichroic ratio in toluidine blue stained sections was observed in A. vera-treated tendons compared with the control. No differences were observed in the chondroitin-6-sulfate and TGF-ß1 levels between the groups, and higher amount of non-collagenous proteins was detected in the A. vera-treated group on the 21(st) day, compared with the control group. No differences were observed in the number of fibroblasts, inflammatory cells and blood vessels between the groups. The application of A. vera during tendon healing modified the arrangement of GAGs and increased the content of GAGs and non-collagenous proteins.

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