Publications by authors named "Marcelo Rodrigues Cunha"

19 Publications

  • Page 1 of 1

Photobiomodulation Therapy as a Possible New Approach in COVID-19: A Systematic Review.

Life (Basel) 2021 Jun 18;11(6). Epub 2021 Jun 18.

Department of Biological Sciences, Bauru School of Dentistry (FOB/USP), University of São Paulo, Bauru 17012-901, SP, Brazil.

COVID-19 is a viral disease characterized as a pandemic by the World Health Organization in March 2020. Since then, researchers from all over the world have been looking for ways to fight this disease. Many cases of complications arise from insufficient immune responses due to low immunity, with intense release of pro-inflammatory cytokines that can damage the structure of organs such as the lung. Thus, the hypothesis arises that photobiomodulation therapy (PBMT) with the use of a low-level laser (LLLT) may be an ally approach to patients with COVID-19 since it is effective for increasing immunity, helping tissue repair, and reducing pro-inflammatory cytokines. This systematic review was performed with the use of PubMed/MEDLINE, Web of Science, Scopus and Google Scholar databases with the following keywords: "low-level laser therapy OR photobiomodulation therapy AND COVID-19". The inclusion criteria were complete articles published from January 2020 to January 2021 in English. The exclusion criteria were other languages, editorials, reviews, brief communications, letters to the editor, comments, conference abstracts, and articles that did not provide the full text. The bibliographic search found 18 articles in the Pubmed/MEDLINE database, 118 articles on the Web of Science, 23 articles on Scopus, and 853 articles on Google Scholar. Ten articles were included for qualitative synthesis, of which four commentary articles discussed the pathogenesis and the effect of PBMT in COVID-19. Two in vitro and lab experiments showed the effect of PBMT on prevention of thrombosis and positive results in wound healing during viral infection, using the intravascular irradiation (ILIB) associated with Phthalomethyl D. Two case reports showed PBMT improved the respiratory indexes, radiological findings, and inflammatory markers in severe COVID-19 patients. One case series reported the clinical improvement after PBMT on 14 acute COVID-19 patients, rehabilitation on 24 patients, and as a preventive treatment on 70 people. One clinical trial of 30 patients with severe COVID-19 who require invasive mechanical ventilation, showed PBMT-static magnetic field was not statistically different from placebo for the length of stay in the Intensive Care Unit, but improved diaphragm muscle function and ventilation and decreased the inflammatory markers. This review suggests that PBMT may have a positive role in treatment of COVID-19. Still, the necessity for more clinical trials remains in this field and there is not sufficient research evidence regarding the effects of PBMT and COVID-19 disease, and there is a large gap.
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http://dx.doi.org/10.3390/life11060580DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8233727PMC
June 2021

Effect of antioxidant treatment with n-acetylcysteine and swimming on lipid expression of sebaceous glands in diabetic mice.

Sci Rep 2021 Jun 7;11(1):11924. Epub 2021 Jun 7.

Morphology and Basic Pathology Department, Jundiaí Medical School (JMS) Jundiaí, Francisco Telles, 250 - Vila Arens II, 1109, Jundiaí, SP, 13202-550, Brazil.

The sebaceous gland (SG) is involved in different inflammatory, infectious and neoplastic processes of the skin and can be related to specific diseases, e.g., diabetes mellitus. Sometimes, the histological diagnosis requires complementary tests due to the ability of diseases to mimic other tumors. We evaluated the sebaceous gland density in Non-obese diabetic mice to analyze the N-acetylcystein effects and swimming exercise treatment in sebaceous glands healing, using specific staining in histochemistry and immunohistochemistry reactions in the identification of the lipid expression in the sebaceous gland. We investigated the intracytoplasmic lipid expression and analysis of gland density from SG in dorsal skin samples from the Non-obese diabetic (NOD mice) and diabetic animals submitted to antioxidant treatment and physical exercise. For histological analysis of the sebaceous glands, specific staining in histochemistry with sudan black and immunohistochemistry reaction with adipophilin were used in the evaluation. Statistical analysis showed significant proximity between the values of the control group and the diabetic group submitted to the swimming exercise (DS group) and similar values between the untreated diabetic group (UD group) and diabetic group treated with the antioxidant N-acetylcysteine (DNa group), which did not prevent possible differences where p < 0.01. Adipophilin (ADPH) immunohistochemistry permitted more intense lipid staining in SGs, the preservation of the SG in the control group, and a morphological deformed appearance in the UD and DNa groups. However, weak morphological recovery of the SG was observed in the DS-Na group, being more expressive in the DS group. In conclusion, the groups submitted to physical exercises showed better results in the recovery of the analyzed tissue, even being in the physiological conditions caused by spontaneous diabetes.
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http://dx.doi.org/10.1038/s41598-021-91459-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8184763PMC
June 2021

Osseointegration Improvement of Co-Cr-Mo Alloy Produced by Additive Manufacturing.

Pharmaceutics 2021 May 14;13(5). Epub 2021 May 14.

Faculty of Medicine of Jundiaí, Jundiaí 13202-550, São Paulo, Brazil.

Cobalt-base alloys (Co-Cr-Mo) are widely employed in dentistry and orthopedic implants due to their biocompatibility, high mechanical strength and wear resistance. The osseointegration of implants can be improved by surface modification techniques. However, complex geometries obtained by additive manufacturing (AM) limits the efficiency of mechanical-based surface modification techniques. Therefore, plasma immersion ion implantation (PIII) is the best alternative, creating nanotopography even in complex structures. In the present study, we report the osseointegration results in three conditions of the additively manufactured Co-Cr-Mo alloy: (i) as-built, (ii) after PIII, and (iii) coated with titanium (Ti) followed by PIII. The metallic samples were designed with a solid half and a porous half to observe the bone ingrowth in different surfaces. Our results revealed that all conditions presented cortical bone formation. The titanium-coated sample exhibited the best biomechanical results, which was attributed to the higher bone ingrowth percentage with almost all medullary canals filled with neoformed bone and the pores of the implant filled and surrounded by bone ingrowth. It was concluded that the metal alloys produced for AM are biocompatible and stimulate bone neoformation, especially when the Co-28Cr-6Mo alloy with a Ti-coated surface, nanostructured and anodized by PIII is used, whose technology has been shown to increase the osseointegration capacity of this implant.
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http://dx.doi.org/10.3390/pharmaceutics13050724DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8156199PMC
May 2021

In Vivo Biological Behavior of Polymer Scaffolds of Natural Origin in the Bone Repair Process.

Molecules 2021 Mar 13;26(6). Epub 2021 Mar 13.

Department of Morphology and Pathology, Medical College of Jundiai, Jundiaí, São Paulo 13202-550, SP, Brazil.

Autologous bone grafts, used mainly in extensive bone loss, are considered the gold standard treatment in regenerative medicine, but still have limitations mainly in relation to the amount of bone available, donor area, morbidity and creation of additional surgical area. This fact encourages tissue engineering in relation to the need to develop new biomaterials, from sources other than the individual himself. Therefore, the present study aimed to investigate the effects of an elastin and collagen matrix on the bone repair process in critical size defects in rat calvaria. The animals (Wistar rats, 30) were submitted to a surgical procedure to create the bone defect and were divided into three groups: Control Group (CG, 10), defects filled with blood clot; E24/37 Group (E24/37, 10), defects filled with bovine elastin matrix hydrolyzed for 24 h at 37 °C and C24/25 Group (C24/25, 10), defects filled with porcine collagen matrix hydrolyzed for 24 h at 25 °C. Macroscopic and radiographic analyses demonstrated the absence of inflammatory signs and infection. Microtomographical 2D and 3D images showed centripetal bone growth and restricted margins of the bone defect. Histologically, the images confirmed the pattern of bone deposition at the margins of the remaining bone and without complete closure by bone tissue. In the morphometric analysis, the groups E24/37 and C24/25 (13.68 ± 1.44; 53.20 ± 4.47, respectively) showed statistically significant differences in relation to the CG (5.86 ± 2.87). It was concluded that the matrices used as scaffolds are biocompatible and increase the formation of new bone in a critical size defect, with greater formation in the polymer derived from the intestinal serous layer of porcine origin (C24/25).
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http://dx.doi.org/10.3390/molecules26061598DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8002007PMC
March 2021

Elastin-derived scaffolding associated or not with bone morphogenetic protein (BMP) or hydroxyapatite (HA) in the repair process of metaphyseal bone defects.

PLoS One 2020 20;15(4):e0231112. Epub 2020 Apr 20.

Department of Morphology and Pathology, Medical College of Jundiai, Jundiaí, São Paulo, Brazil.

Tissue engineering represents a promising alternative for reconstructive surgical procedures especially for the repair of bone defects that do not regenerate spontaneously. The present study aimed to evaluate the effects of the elastin matrix (E24/50 and E96/37) incorporated with hydroxyapatite (HA) or morphogenetic protein (BMP) on the bone repair process in the distal metaphysis of rat femur. The groups were: control group (CG), hydrolyzed elastin matrix at 50°C/24h (E24/50), E24/50 + HA (E24/50/HA), E24/50 + BMP (E24/50/BMP), hydrolyzed elastin matrix at 37°C/96h (E96/37), E96/37 + HA (E96/37/HA), E96/37 + BMP (E96/37/BMP). Macroscopic and radiographic analyses showed longitudinal integrity of the femur in all groups without fractures or bone deformities. Microtomographically, all groups demonstrated partial closure by mineralized tissue except for the E96/37/HA group with hyperdense thin bridge formation interconnecting the edges of the ruptured cortical. Histologically, there was no complete cortical recovery in any group, but partial closure with trabecular bone. In defects filled with biomaterials, no chronic inflammatory response or foreign body type was observed. The mean volume of new bone formed was statistically significant higher in the E96/37/HA and E24/50 groups (71.28 ± 4.26 and 66.40 ± 3.69, respectively) than all the others. In the confocal analysis, it was observed that all groups presented new bone markings formed during the experimental period, being less evident in the CG group. Von Kossa staining revealed intense calcium deposits distributed in all groups. Qualitative analysis of collagen fibers under polarized light showed a predominance of red-orange birefringence in the newly regenerated bone with no difference between groups. It was concluded that the E24/50 and E96/37/HA groups promoted, with greater speed, the bone repair process in the distal metaphysis of rat femur.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0231112PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7170266PMC
July 2020

Anatomical study of the brachial plexus in human fetuses and its relation with neonatal upper limb paralysis.

Einstein (Sao Paulo) 2020 27;18:eAO5051. Epub 2020 Jan 27.

Faculdade de Medicina de Jundiaí, Jundiaí, SP, Brazil.

Objective: To study the anatomy of the brachial plexus in fetuses and to evaluate differences in morphology during evolution, or to find anatomical situations that can be identified as the cause of obstetric paralysis.

Methods: Nine fetuses (12 to 30 weeks of gestation) stored in formalin were used. The supraclavicular and infraclavicular parts of the brachial plexus were dissected.

Results: In its early course, the brachial plexus had a cord-like shape when it passed through the scalene hiatus. Origin of the phrenic nerve in the brachial plexus was observed in only one fetus. In the deep infraclavicular and retropectoralis minor spaces, the nerve fibers of the brachial plexus were distributed in the axilla and medial bicipital groove, where they formed the nerve endings.

Conclusion: The brachial plexus of human fetuses presents variations and relations with anatomical structures that must be considered during clinical and surgical procedures for neonatal paralysis of the upper limbs.
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http://dx.doi.org/10.31744/einstein_journal/2020AO5051DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6980293PMC
March 2020

Suitability of the use of an elastin matrix combined with bone morphogenetic protein for the repair of cranial defects.

Am J Transl Res 2019 15;11(8):5261-5271. Epub 2019 Aug 15.

Department of Morphology and Pathology, Medical College of Jundiai São Paulo, Jundiaí 13202-550, SP, Brazil.

The use of biomaterials in medical and dental areas has become increasingly important due to the need to restore areas with bone loss or defects. This study analyzed the use of a new elastin polymer matrix combined with Bone Morphogenetic Protein for the repair of cranial defects in rats. Thirty rats were divided into five groups: control (C) defect without graft, E24 (defect filled with elastin matrix submitted to alkaline hydrolysis at 50°C for 24 h), E24/BMP (defect filled with elastin matrix treated at 50°C for 24 h plus BMP), E96 (defect filled with elastin matrix treated at 37°C for 96 h) and E96/BMP (defect filled with elastin matrix treated at 37°C for 96 h plus BMP). The animals were killed after 6 weeks. In the histological and microtomographic analysis, all groups showed bone growth from the defect margins remaining in this region without a marked inflammatory process, but in the E96/BMP group the lamellae were thicker and the collagen fibers more organized. Histometrically, the same group presented higher percentage of new formation (43.25 ± 3.72) in relation to the other groups. It was concluded that the support and delivery system formed by the elastin matrix associated with BMPs had a positive effect on the bone repair process.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6731398PMC
August 2019

Effects of the combination of low-level laser therapy and anionic polymer membranes on bone repair.

Lasers Med Sci 2020 Jun 29;35(4):813-821. Epub 2019 Aug 29.

Department of Morphology and Pathology, Faculty of Medicine of Jundiaí, Francisco Telles st., 250, Vila Arens, Jundiaí, São Paulo, 13202-550, Cx Postal 1295, Brazil.

In view of the limitations of bone reconstruction surgeries using autologous grafts as a gold standard, tissue engineering is emerging as an alternative, which permits the fabrication and improvement of scaffolds to stimulate osteogenesis and angiogenesis, processes that are essential for bone repair. Polymers are used to mimic the extracellular bone matrix and support cell growth. In addition, bone neoformation can be induced by external factors such as laser irradiation, which stimulates bone metabolism. The objective of this study was to evaluate the regeneration of bone defects using collagen and elastin membranes derived from intestinal serosa and bovine auricular cartilage combined with low-level laser application. Thirty-six Wistar rats were operated to create a 3-mm defect in the distal metaphysis of the left femur and divided into six groups: G1 (control, no treatment); G2 (laser); G3 (elastin graft), G4 (elastin+laser); G5 (collagen graft); G6 (collagen+laser). The animals were sacrificed 6 weeks after surgery and the femurs were removed for analysis of bone repair. Macroscopic and radiological results showed the absence of an infectious process in the surgical area. This was confirmed by histological analysis, which revealed no inflammatory infiltrate. Histomorphometry showed that the formation of new bone started from the margins of the bone defect and its volume was greater in elastin+laser and collagen+laser. We conclude that newly formed bone in the graft area was higher in the groups that received the biomaterials and laser. The collagen and elastin matrices showed biocompatibility.
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http://dx.doi.org/10.1007/s10103-019-02864-8DOI Listing
June 2020

Use of an anionic collagen matrix made from bovine intestinal serosa for in vivo repair of cranial defects.

PLoS One 2018 12;13(7):e0197806. Epub 2018 Jul 12.

Department of Morphology and Pathology, Faculty of Medicine of Jundiaí, São Paulo, Brazil, Jundiaí -SP, Brazil.

Polymeric biomaterials composed of extracellular matrix components possess osteoconductive capacity that is essential for bone healing. The presence of collagen and the ability to undergo physicochemical modifications render these materials a suitable alternative in bone regenerative therapies. The objective of this study was to evaluate the osteogenic capacity of collagen-based matrices (native and anionic after alkaline hydrolysis) made from bovine intestinal serosa (MBIS). Twenty-five animals underwent surgery to create a cranial defect to be filled with native and anionic collagen matrixes, mmineralized and non mineralized. The animals were killed painlessly 6 weeks after surgery and samples of the wound area were submitted to routine histology and morphometric analysis. In the surgical area there was new bone formation projecting from the margins to the center of the defect. More marked bone neoformation occurred in the anionic matrices groups in such a way that permitted union of the opposite margins of the bone defect. The newly formed bone matrix exhibited good optical density of type I collagen fibers. Immunoexpression of osteocalcin by osteocytes was observed in the newly formed bone. Morphometric analysis showed a greater bone volume in the groups receiving the anionic matrices compared to the native membranes. Mineralization of the biomaterial did not increase its osteoregenerative capacity. In conclusion, the anionic matrix exhibits osteoregenerative capacity and is suitable for bone reconstruction therapies.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0197806PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6042682PMC
December 2018

Role of GAD peptides p217 and p290 in the repair of INS receptor in salivary tissues of type 1 diabetic mice.

Pak J Pharm Sci 2017 Sep;30(5):1545-1550

Tissue Morphology Laboratory, Department of Morphology and Basic Pathology, Faculty of Medicine of Jundiaí, São Paulo, Brazil.

Glutamate decarboxylase or glutamic acid decarboxylase (GAD) is a protein associated with autoimmune diseases, including type-1 diabetes. This disease is primarily associated with the occurrence of a specific isoform: GAD65. Conversely, some specific peptides of this protein may block autoimmunity in diabetes. In this respect, understanding the relationship between GAD and the development of diabetes is important, and it is necessary to understand the role of each GAD peptide to design effective autoimmune diabetes treatments. The purpose of the present study was to analyze the effects of treatment with GAD-derived peptides p217 and p290 on INS receptors in the salivary epithelium of nonobese diabetic (NOD) animals. Three groups of 7 mice each were studied: I, BALB/c mice (control); II, NOD mice; and III, NOD mice treated with peptides p290 and p217. Groups I and II only received buffered saline solution. Glucose levels were measured daily during the 21 days of the experiment. After the study, the animals were euthanized and the parotid and submandibular glands were removed for the analysis of INS-R by fluorescence microscopy. Therapy with two peptides together was associated with reduced glucose levels in NOD mice and intense INS-R expression in both salivary organs. Our approach of combining GAD p217 and p290 peptides contributed to hormonal balance and promoted the repair of INS-R.
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September 2017

A new heterologous fibrin sealant as scaffold to recombinant human bone morphogenetic protein-2 (rhBMP-2) and natural latex proteins for the repair of tibial bone defects.

Acta Histochem 2015 Apr 29;117(3):288-96. Epub 2015 Mar 29.

Department of Morphology and Pathology, School of Medicine of Jundiaí, Rua Francisco Telles, 250, Vila Arens, Cx. Postal 1295, Jundiaí CEP: 13202-550, SP, Brazil. Electronic address:

Tissue engineering has special interest in bone tissue aiming at future medical applications Studies have focused on recombinant human bone morphogenetic protein-2 (rhBMP-2) and natural latex proteins due to the osteogenic properties of rhBMP-2 and the angiogenic characteristic of fraction 1 protein (P-1) extracted from the rubber tree Hevea brasiliensis. Furthermore, heterologous fibrin sealant (FS) has been shown as a promising alternative in regenerative therapies. The aim of this study was to evaluate these substances for the repair of bone defects in rats. A bone defect measuring 3mm in diameter was created in the proximal metaphysis of the left tibia of 60 rats and was implanted with rhBMP-2 or P-1 in combination with a new heterologous FS derived from snake venom. The animals were divided into six groups: control (unfilled bone defect), rhBMP-2 (defect filled with 5μg rhBMP-2), P-1 (defect filled with 5μg P-1), FS (defect filled with 8μg FS), FS/rhBMP-2 (defect filled with 8μg FS and 5μg rhBMP-2), FS/P-1 (defect filled with 8μg FS and 5μg P-1). The animals were sacrificed 2 and 6 weeks after surgery. The newly formed bone projected from the margins of the original bone and exhibited trabecular morphology and a disorganized arrangement of osteocyte lacunae. Immunohistochemical analysis showed intense expression of osteocalcin in all groups. Histometric analysis revealed a significant difference in all groups after 2 weeks (p<0.05), except for the rhBMP-2 and FS/rhBMP-2 groups (p>0.05). A statistically significant difference (p<0.05) was observed in all groups after 6 weeks in relation to the volume of newly formed bone in the surgical area. In conclusion, the new heterologous fibrin sealant was found to be biocompatible and the combination with rhBMP-2 showed the highest osteogenic and osteoconductive capacity for bone healing. These findings suggest a promising application of this combination in the regeneration surgery.
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http://dx.doi.org/10.1016/j.acthis.2015.03.006DOI Listing
April 2015

Use of a new fibrin sealant and laser irradiation in the repair of skull defects in rats.

Braz Dent J 2013 Sep-Oct;24(5):456-61

Department of Morphology and Pathology, FMJ - Medical School of Jundiai, JundiaíSP, Brazil.

This study evaluated the osteogenic capacity of a new fibrin sealant (FS) combined with bone graft and laser irradiation in the bone repair. Defects were created in the skull of 30 rats and filled with autogenous graft and FS derived from snake venom. Immediately after implantation, low-power laser was applied on the surgical site. The animals were divided in: control group with autogenous graft (G1), autogenous graft and laser 5 J/cm2 (G2), autogenous graft and laser 7 J/cm2 (G3), autogenous graft and FS (G4), autogenous graft, FS and laser 5 J/cm2 (G5), autogenous graft, FS and laser 7 J/cm2 (G6). The animals were sacrificed 6 weeks after implant. Results showed absence of inflammatory infiltrate in the bone defect. New bone formation occurred in all groups, but it was most intense in G6. Thus, the FS and laser 7 J/cm2 showed osteoconductive capacity and can be an interesting resource to be applied in surgery of bone reconstruction.
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http://dx.doi.org/10.1590/0103-6440201302265DOI Listing
November 2015

Osteoconductive capacity of hydroxyapatite implanted into the skull of diabetics.

J Craniofac Surg 2011 Nov;22(6):2048-52

Department of Morphology and Pathology, Faculty of Medicine of Jundiaí, Jundiaí, São Paulo, Brazil.

Diabetes mellitus can cause various diseases, including loss of bone mineral density as a characteristic manifestation of osteoporosis. In this condition, bone is more vulnerable to pathologic fractures that can be treated by implantation of biomaterial grafts. The aim of this study was to evaluate the osteogenic capacity of hydroxyapatite implanted into bone defects in the skull of nonobese diabetic mice. Fifteen nonobese diabetic mice were divided into 3 groups: control (nondiabetic), spontaneously diabetic, and spontaneously diabetic receiving insulin replacement applied subcutaneously into the dorsum. Defects were created experimentally in the skull with a surgical bur and filled with hydroxyapatite granules. The animals were killed 4 weeks after surgery, and samples were obtained for analysis. Quantitative methods were used for measurement of the new bone formation. Data were analyzed by analysis of variance followed by the Tukey test (P < 0.05). Radiographic results showed good radiopacity of the hydroxyapatite; however, radiolucent spots were seen between the hydroxyapatite granules in the diabetic groups, indicating infiltration of connective tissue. Microscopic results showed projections of newly formed bone from the margin of bone defect toward the implant. The quantity of newly formed bone was significantly higher (P < 0.05) than that observed in the diabetic groups. The recipient area of diabetic groups contained a larger amount of connective tissue as demonstrated by radiographic analyses. In conclusion, the osteogenesis guided by the properties of hydroxyapatite may even occur in bone suffering from the effects of diabetes, but the quantity of newly formed bone is lower, and the process is slower.
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http://dx.doi.org/10.1097/SCS.0b013e3182319876DOI Listing
November 2011

Study of the osteoconductive capacity of hydroxyapatite implanted into the femur of ovariectomized rats.

Microsc Res Tech 2012 Feb 14;75(2):133-7. Epub 2011 Jul 14.

Departamento de Morfologia e Patologia Básica da Faculdade de Medicina de Jundiaí, Rua Francisco Telles, 250, Vila Arens, Jundiaí-SP, Brazil.

Osteoporosis is a global public health that affects postmenopausal women due to the deficiency of estrogen, a hormone that plays an important role in the microarchitecture of bone tissue. Osteoporosis predisposes to pathological bone fracture that can be repaired by conventional methods. However, depending on the severity and quantity of bone loss, the use of autogenous grafts or biomaterials such as hydroxyapatite might be necessary. The latter has received increasing attention in the medical field because of its good biological properties such as osteoconductivity and biocompatibility with bone tissue. The objective of this study was to evaluate using histologic and radiographic analyses, the osteogenic capacity of hydroxyapatite implanted into the femur of rats with ovariectomy-induced osteoporosis. Eighteen rats were divided into three groups with six animals in each: group nonovariectomized, bilaterally ovariectomized not receiving estrogen replacement therapy, and bilaterally ovariectomized submitted to estrogen replacement therapy. Defects were created experimentally in the distal epiphysis of the femur with a surgical drill and filled with porous hydroxyapatite granules. The animals were sacrificed 8 weeks after surgery. The volume of newly formed bone in the implant area was quantified by morphometrical methods. The results were analyzed by ANOVA followed by the Tukey test (P < 0.05). The hydroxyapatite granules showed good radiopacity. Histological analysis revealed less quantity of newly formed bone in the ovariectomized group not submitted to hormone replacement therapy. In conclusion, bone neoformation can be expected even in bones compromised by estrogen deficiency, but the quantity and velocity of bone formation are lower.
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http://dx.doi.org/10.1002/jemt.21035DOI Listing
February 2012

Effect of alveolex on the bone defects repair stimulated by rhBMP-2: Histomorphometric study.

Microsc Res Tech 2012 Jan 26;75(1):36-41. Epub 2011 May 26.

Department of Dental Materials and Prosthodontics, Faculty of Dentistry of Ribeirão Preto, University of São Paulo, Avenida Café s/n, Ribeirão Preto, SP, Brazil.

Objective: The aim of this study was to evaluate histomorphometrically the effect of alveolex (Propolis 10%) on the repair of bone cavities in the calvaria of rats.

Materials And Methods: A 5 mm diameter bone defect was made in the calvaria of male Wistar rats using the drill-type trephine. The defects were filled with rhBMP-2+Alveolex, rhBMP-2, Alveolex, or coagulum. Twenty-eight animals with seven subjects on each were sacrificed 30 days after surgery and samples were fixed and embedded in paraffin. Histological sections stained by HE (hematoxylin and eosin) were obtained from the calvaria bone defect and analyzed by a differential point-counting method.

Results: Group I and II, rhBMP-2+Alveolex and rhBMP-2, respectively, presented higher levels of newly formed bone than other groups (P < 0.001). There were not significant differences between groups I and II (P > 0.05). In addition, there was not significant difference between groups III and IV, Control-Coagulum and Alveolex, respectively (P > 0.05).

Conclusion: Alveolex has increased the bone repair in calvaria defects of rats when associated to rhBMP-2, however without significant differences for rhBMP-2 isolated group; Alveolex isolated group showed the lowest levels of newly formed bone with no significant differences to coagulum group (control).
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http://dx.doi.org/10.1002/jemt.21019DOI Listing
January 2012

Epithelial-stromal interactions in salivary glands of rats exposed to chronic passive smoking.

Arch Oral Biol 2011 Jun 18;56(6):580-7. Epub 2010 Dec 18.

Tissue Morphology Laboratory, Department of Morphology and Basic Pathology, Faculty of Medicine of Jundiaí, Jundiaí, São Paulo, Brazil.

Objectives: Cigarette smoke leads to precancerous and cancerous lesions in the mouth even when the exposure is passive. The salivary glands are amongst the tissues exposed to the smoke but it is unclear whether or not passive cigarette exposure is related to detectable changes in these tissues. The objective of this study was to observe the tissue architecture of the parotid and submandibular glands in rats after passive cigarette exposure and to measure any changes that occurred.

Design: Twenty Wistar rats were divided into 10 non-smoking animals and 10 animals exposed to cigarette smoke. After 6 months of smoke exposure samples were collected from both exposed and unexposed salivary glands for histological examination under both transmitted and polarized light microscopy.

Results: Changes in the glands of exposed animals included involution of the cytoplasm and nucleus of the acinar cells and the presence of an inflammatory infiltrate. There was an abnormal accumulation of type I collagen in the stroma and an enlarged interacinar space filled with extracellular matrix.

Conclusion: Passive smoking led to substantial structural changes in the salivary glands which could significantly affect function.
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http://dx.doi.org/10.1016/j.archoralbio.2010.11.017DOI Listing
June 2011

BIOMATERIAL IMPLANTS IN BONE FRACTURES PRODUCED IN RATS FIBULAS.

Rev Bras Ortop 2010 Sep-Oct;45(5):478-82. Epub 2015 Dec 12.

Department of Morphology and Basic Pathology, Discipline of Anatomy, Jundiaí School of Medicine, Jundiaí, SP, Brazil.

Unlabelled: To evaluate the importance of collagen and hydroxyapatite in the regeneration of fractures experimentally induced in the fibulas of rats.

Method: 15 rats were used. These were subjected to surgery to remove a fragment from the fibula. This site then received a graft consisting of a silicone tubes filled with hydroxyapatite and collagen.

Results: Little bone neoformation occurred inside the tubes filled with the biomaterials. There was more neoformation in the tubes with collagen.

Conclusion: The biomaterials used demonstrated biocompatibility and osteoconductive capacity that was capable of stimulating osteogenesis, even in bones with secondary mechanical and morphological functions such as the fibula of rats.
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http://dx.doi.org/10.1016/S2255-4971(15)30439-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4799216PMC
April 2016

Implants of polyanionic collagen matrix in bone defects of ovariectomized rats.

J Mater Sci Mater Med 2008 Mar 4;19(3):1341-8. Epub 2007 Oct 4.

Department of Cell Biology, Institute of Biology, State University of Campinas, P.O. Box 6109, Campinas, SP 13084-971, Brazil.

In recent years, there has been a great interest in the development of biomaterials that could be used in the repair of bone defects. Collagen matrix (CM) has the advantage that it can be modified chemically to improve its mechanical properties. The aim of the present study was to evaluate the effect of three-dimensional membranes of native or anionic (submitted to alkaline treatment for 48 or 96 h) collagen matrix on the consolidation of osteoporosis bone fractures resulting from the gonadal hormone alterations caused by ovariectomy in rats subjected to hormone replacement therapy. The animals received the implants 4 months after ovariectomy and were sacrificed 8 weeks after implantation of the membranes into 4-mm wide bone defects created in the distal third of the femur with a surgical bur. Macroscopic analysis revealed the absence of pathological alterations in the implanted areas, suggesting that the material was biocompatible. Microscopic analysis showed a lower amount of bone ingrowth in the areas receiving the native membrane compared to the bone defects filled with the anionic membranes. In ovariectomized animals receiving anionic membranes, a delay in bone regeneration was observed mainly in animals not subjected to hormone replacement therapy. We conclude that anionic membranes treated with alkaline solution for 48 and 96 h presented better results in terms of bone ingrowth.
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http://dx.doi.org/10.1007/s10856-006-0105-yDOI Listing
March 2008

Subperiosteal hydroxyapatite implants in rats submitted to ethanol ingestion.

Arch Oral Biol 2004 Sep;49(9):747-53

Department of Anatomy, Institute of Biology, State University of Campinas, CP 6109, CEP 13084971, Sao Paulo, Brazil.

It has been reported that excessive alcohol consumption can contribute to failures on the osteointegration process in the site of implantation. Hydroxyapatite blocks were implanted under the periosteum of the femur and skull of 40 rats divided into two groups of 20 animals, one of them received 25% ethanol diluted in water and the other did not. Bone formation close to the hydroxyapatite implant was observed in the femur of all animals 2 weeks after surgery, however the bone volume was lower in ethanol-treated animals. It was observed in the skulls of the ethanol-treated animals a delay in new bone formation process, as a lower bone volume, too. After 4 weeks of the implantation, just one ethanol-treated animal showed no new bone formation in the femur, while no bone formation was observed in the skulls of two other rats. On the 8th and 16th weeks, bone formation was observed in both femur and skull from both groups, although always with less volume in ethanol-treated rats. We concluded that ethanol consumption did not impair osteointegration of ceramic implants, but it might have reduced the osteogenic capacity of periosteal cells in the femur and parietal bone of the rats.
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September 2004
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