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1.
Molecules ; 26(6)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805847

RESUMO

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, n = 30) were submitted to a surgical procedure to create the bone defect and were divided into three groups: Control Group (CG, n = 10), defects filled with blood clot; E24/37 Group (E24/37, n = 10), defects filled with bovine elastin matrix hydrolyzed for 24 h at 37 °C and C24/25 Group (C24/25, n = 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).


Assuntos
Biopolímeros/química , Regeneração Óssea/fisiologia , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Birrefringência , Matriz Óssea/química , Matriz Óssea/fisiologia , Remodelação Óssea/fisiologia , Substitutos Ósseos/química , Calcificação Fisiológica/fisiologia , Bovinos , Colágeno/química , Colágeno/metabolismo , Elastina/química , Elastina/metabolismo , Imageamento Tridimensional , Masculino , Teste de Materiais , Ratos , Ratos Wistar , Crânio/diagnóstico por imagem , Crânio/lesões , Crânio/fisiologia , Suínos , Engenharia Tecidual/métodos , Microtomografia por Raio-X
2.
Arq. bras. med. vet. zootec. (Online) ; 73(1): 132-140, Jan.-Feb. 2021. ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-1153043

RESUMO

Defeitos ósseos constituem um problema de saúde global. O sistema Rigenera permite a extração de microenxertos ricos em células-tronco mesenquimais (CTMs). Objetivou-se avaliar o processo de regeneração óssea por enxertos obtidos pelo sistema Rigenera em defeitos críticos na calvária de ratos. Foram utilizados 18 ratos Wistar, machos, pesando 285±29g, distribuídos em três grupos (n=6), sendo cada animal controle de si mesmo, denominados G15-Controle e G15-Tratado (15 dias); G30-Controle e G30-Tratado (30 dias) e G60-Controle e G60-Tratado (60 dias). Foram realizadas duas lesões de 5mm de diâmetro em cada antímero da calvária. Nos grupos tratados, foram utilizados microenxertos autólogos de cartilagem xifoide, obtidos pelo sistema Rigenera. O defeito contralateral serviu como controle em todos os animais. Os animais foram eutanasiados aos 15, 30 e 60 dias após a cirurgia, e as amostras foram processadas para a histoquímica. Nos grupos controle, não foram observados sinais de regeneração óssea, enquanto nos grupos tratamento foram verificadas áreas de formação óssea e tecido mesenquimal ativado. O sistema Rigenera foi eficiente na obtenção de microenxertos autólogos, para terapia celular em defeito crítico de calvária de ratos. Com o aprimoramento do protocolo, o sistema Rigenera poderá ser amplamente utilizado no tratamento de lesões ósseas.(AU)


Bone defects are a global health problem. The Rigenera system allows the extraction of micro grafts rich in mesenchymal stem cells (MSCs). The objective of this study was to evaluate the bone regeneration process by grafts obtained by the Rigenera system in defects in the rats calvarian. Eighteen male Wistar rats were used, weighing 285 ± 29g, distributed in three groups (n = 6), where each animal was treatment and control, called G15-Control and G15-Treated (15 days); G30-Control and G30-Treated (30 days) and G60-Control and G60-Treated (60 days). Two 5mm diameter lesions were performed on each calvaria side. In the treated groups, autologous micrograft from xiphoid cartilage, obtained by the Rigenera system, were used. The other defect served as a control in all animals. The animals were euthanized at 15, 30 and 60 days after the surgery and the samples were processed for histochemistry. In the control groups, no signs of bone regeneration were observed, while in the treatment groups, areas of bone formation and activated mesenchymal tissue were verified. The Rigenera system was efficient in obtaining autologous micrograft for cell therapy in a critical calvaria defect in rats. Rigenera system can be widely used in the treatment of bone injuries.(AU)


Assuntos
Animais , Ratos , Crânio/lesões , Regeneração Óssea , Células-Tronco Mesenquimais , Traumatismos Craniocerebrais/terapia , Traumatismos Craniocerebrais/veterinária , Ratos Wistar/lesões , Autoenxertos
3.
Am J Phys Anthropol ; 174(4): 614-630, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33382102

RESUMO

OBJECTIVES: This study uses osteological and radiocarbon datasets combined with formal quantitative analyses to test hypotheses concerning the character of conflict in the Nasca highlands during the Late Intermediate Period (LIP, 950-1450 C.E.). We develop and test osteological expectations regarding what patterns should be observed if violence was characterized by intragroup violence, ritual conflict, intermittent raiding, or internecine warfare. MATERIALS AND METHODS: Crania (n = 267) were examined for antemortem and perimortem, overkill, and critical trauma. All age groups and both sexes are represented in the sample. One hundred twenty-four crania were AMS dated, allowing a detailed analysis of diachronic patterns in violence among various demographic groups. RESULTS: Thirty-eight percent (102/267) of crania exhibit some form of cranial trauma, a significant increase from the preceding Middle Horizon era. There are distinct trauma frequencies within the three subphases of the LIP, but Phase III (1300-1450 C.E.) exhibits the highest frequencies of all trauma types. Males exhibit significantly more antemortem trauma than females, but both exhibit similar perimortem trauma rates. DISCUSSION: There was chronic, internecine warfare throughout the Late Intermediate Period with important variations in violence throughout the three temporal phases. Evidence for heterogeneity in violent mortality shows a pattern consistent with social substitutability, whereby any and all members of the Nasca highland population were appropriate targets for lethal and sublethal violence. We argue that by testing hypotheses regarding the targets and types of conflict we are better able to explain the causes and consequences of human conflict.


Assuntos
Indígenas Sul-Americanos/etnologia , Indígenas Sul-Americanos/história , Violência/etnologia , Violência/história , Adolescente , Adulto , Antropologia Física , Criança , Pré-Escolar , Feminino , História do Século XV , História Medieval , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Peru/etnologia , Crânio/lesões , Crânio/patologia , Guerra/etnologia , Guerra/história , Adulto Jovem
4.
J Biomater Appl ; 35(2): 205-214, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32362163

RESUMO

Biomaterials and bone grafts, with the ability of stimulating tissue growth and bone consolidation, have been emerging as very promising strategies to treat bone fractures. Despite its well-known positive effects of biosilicate (BS) on osteogenesis, its use as bone grafts in critical situations such as bone defects of high dimensions or in non-consolidated fractures may not be sufficient to stimulate tissue repair. Consequently, several approaches have been explored to improve the bioactivity of BS. A promising strategy to reach this aim is the inclusion of an organic part, such as collagen, in order to mimic bone structure. Thus, the present study investigated the biological effects of marine spongin (SPG)-enriched BS composites on the process of healing, using a critical experimental model of cranial bone defect in rats. Histopathological and immunohistochemistry analyzes were performed after two and six weeks of implantation to investigate the effects of the material on bone repair (supplemental material-graphical abstract). Histological analysis demonstrated that for both BS and BS/SPG, similar findings were observed, with signs of material degradation, the presence of granulation tissue along the defect area and newly formed bone into the area of the defect. Additionally, histomorphometry showed that the control group presented higher values for Ob.S/BS (%) and for N.Ob/T.Ar (mm2) (six weeks post-surgery) compared to BS/SPG and higher values of N.Ob/T.Ar (mm2) compared to BS (two weeks post-surgery). Moreover, BS showed higher values for OV/TV (%) compared to BS/SPG (six weeks post-surgery). Also, VEGF immunohistochemistry was increased for BS (two weeks post-surgery) and for BS/SPG (six weeks) compared to CG. TGFb immunostaining was higher for BS compared to CG. The results of this study demonstrated that the BS and BS/SPG scaffolds were biocompatible and able to support bone formation in a critical bone defect in rats. Moreover, an increased VEGF immunostaining was observed in BS/SPG.


Assuntos
Materiais Biocompatíveis/química , Vidro/química , Poríferos/química , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/uso terapêutico , Masculino , Ratos Wistar , Crânio/lesões , Crânio/patologia , Crânio/ultraestrutura , Engenharia Tecidual/métodos
5.
Am J Phys Anthropol ; 172(2): 246-269, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31943137

RESUMO

OBJECTIVES: This study examines violence-related cranial trauma frequencies and wound characteristics in the pre-Hispanic cemetery of Uraca in the lower Majes Valley, Arequipa, Peru, dating to the pre- and early-Wari periods (200-750 CE). Cranial wounds are compared between status and sex-based subgroups to understand how violence shaped, and was shaped by, these aspects of identity, and to reconstruct the social contexts of violence carried out by and against Uracans. MATERIALS AND METHODS: Presence, location, and characteristics (lethality, penetration, and post-traumatic sequelae) of antemortem and perimortem cranial fractures are documented for 145 crania and compared between subgroups. Cranial wounds are mapped in ArcGIS and the locational distribution of injuries is compared between male and female crania. RESULTS: Middle adult males were disproportionately interred at Uraca, particularly in the elite Sector I. The Uraca mortuary population presents the highest rate of cranial trauma reported for pre-Hispanic Peru: 67% of adults present trauma, and among those, 61.1% present more than one cranial injury. Males exhibit significantly more cranial trauma than females and present a higher mean number of injuries per person. Elite males show the highest mean number of injuries per person, more antemortem injuries, and are the only ones with perimortem cranial trauma, bladed injuries, penetrating injuries, and post-traumatic sequelae. Both sexes were most frequently injured on the anterior of the cranium, while the proportion of posterior injuries was higher for females. DISCUSSION: The rate, intensity, and locational patterns of cranial trauma suggests the community was engaged in raids and/or war with enemy groups, some of which may have increased physical violence between community members. Engaging in violence was likely a prerequisite for burial in the elite sector and was bound up with the generation and maintenance of social status differences linked to male social life.


Assuntos
Traumatismos Craniocerebrais , Indígenas Sul-Americanos , Crânio/lesões , Violência , Adulto , Arqueologia , Traumatismos Craniocerebrais/etnologia , Traumatismos Craniocerebrais/história , Traumatismos Craniocerebrais/patologia , Feminino , História Antiga , História Medieval , Humanos , Indígenas Sul-Americanos/etnologia , Indígenas Sul-Americanos/história , Masculino , Peru/etnologia , Violência/etnologia , Violência/história
6.
J Biomed Mater Res A ; 108(3): 446-457, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31657517

RESUMO

Here, we investigated the biocompatibility of a bioactive sodium calcium silicate glass containing 2.6 mol% Nb2 O5 (denoted BGPN2.6) and compare the results with the archetypal 45S5 bioglass. The glass bioactivity was tested using a range of in vitro and in vivo experiments to assess its suitability for bone regeneration applications. in vitro studies consisted of assessing the cytocompatibility of the BGPN2.6 glass with bone-marrow-derived mesenchymal stem cells (BM-MSCs). Systemic biocompatibility was verified by means of the quantification of biochemical markers and histopathology of liver, kidneys, and muscles. The glass genotoxicity was assessed using the micronucleus test. The regeneration of a calvarial defect was assessed using both qualitative and quantitative analysis of three-dimensional microcomputed tomography images. The BGPN2.6 glass was not cytotoxic to BM-MSCs. It is systemically biocompatible causing no signs of damage to high metabolic and excretory organs such as the liver and kidneys. No mutagenic potential was observed in the micronucleus test. MicroCT images showed that BGPN2.6 was able to nearly fully regenerate a critical-sized calvarial defect and was far superior to standard 45S5 Bioglass. Defects filled with BGPN2.6 glass showed over 90% coverage compare to just 66% for 45S5 Bioglass. For one animal the defect was completely filled in 8 weeks. These results clearly show that Nb-containing bioactive glasses are a safe and effective biomaterial for bone replacement.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/farmacologia , Cerâmica/farmacologia , Nióbio/farmacologia , Animais , Linhagem Celular , Vidro , Humanos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Ratos , Crânio/efeitos dos fármacos , Crânio/lesões
7.
Clin Oral Investig ; 24(5): 1637-1650, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31338633

RESUMO

OBJECTIVES: The effect of leucocyte- and platelet-rich fibrin (L-PRF), associated with DBBM (deproteinized bovine bone mineral; Bio-Oss®) was investigated and compared with autogenous bone graft as a standard material for filling bone defects. MATERIAL AND METHODS: A defect of 5 mm in diameter was performed in 40 calvaria of rats. The animals were divided into 5 groups and received blood clot (CO), autogenous bone (AUT), DBBM (BIO), L-PRF, or DBBM associated with L-PRF (BIO-LPRF). After 4 and 8 weeks, bone regeneration was assessed by histometric and immunohistochemical analyses. RESULTS: The highest mean percentage of bone formation found at 4 and 8 weeks was observed for the BIO-L-PRF group (54.0% ± 2.8 and 63.6% ± 2.2). The lowest mean percentage at 4 and 8 weeks was observed for the CO group (16.7% ± 2.5 and 20.5% ± 1.0). There was statistical similarity among the AUT, BIO, and L-PRF groups. The expressions OC, RUNX 2, and VEGF showed a favorable aspect in the formation of new bone for BIO-L-PRF. VEGF was the marker with the highest expression because it was related to the initial healing process, promoting the migration and proliferation of endothelial cells in the region of the defect. Even after weeks, VEGF maintained a moderate expression. CONCLUSIONS: The association of L-PRF with DBBM improved bone repair when these biomaterials were inserted into the defects of the calvaria of rats. CLINICAL RELEVANCE: This reinforces the good performance of bovine bone and L-PRF as filler materials, especially when associated.


Assuntos
Regeneração Óssea , Substitutos Ósseos/uso terapêutico , Minerais/uso terapêutico , Fibrina Rica em Plaquetas , Crânio/lesões , Animais , Bovinos , Células Endoteliais/citologia , Ratos
8.
Rio de Janeiro; s.n; 2020. 65 p. ilus..
Tese em Português | BBO - Odontologia, LILACS | ID: biblio-1532545

RESUMO

O presente trabalho teve como objetivo avaliar a regeneração óssea de defeitos ósseos críticos na calvária de ratos com a utilização de enxerto xenógeno Bio-Oss Small ( Bio-Oss® Geistlich Pharma AG, Wolhusen, Suíça) e hidroxiapatita sintética, (Alobone poros Osseocon Biomateriais Ltda., Rio de Janeiro/RJ, Brasil ) puros e enriquecidos com a fração mononuclear medular de célula tronco. Material e métodos: quarenta ratos adultos jovens machos, Sprague Dawley, com doze semanas distribuídos em cinco grupos com oito animais, sendo assim denominados: grupo controle, grupo 1, grupo 2, grupo 3, e grupo 4. Além dos quarenta ratos adultos jovens, mais oito ratos adultos jovens machos, Sprague Dawley, com doze semanas foram utilizados como doadores de medula óssea. Os cinco grupos foram submetidos a defeitos ósseos críticos com trefina de 8 (oito) milímetros de diâmetro, na região temporoparietal. No grupo controle não teve a colocação de biomaterial, no grupo 1 os defeitos críticos foram preenchidos por hidroxiapatita sintética ,0.10 gramas, (Alobone poros Osseocon Biomateriais Ltda., Rio de Janeiro/RJ, Brasil), no grupo 2 foram preenchidos com hidroxiapatita bovina,0,10 gramas, Bio-Oss Small (Bio-Oss® Geistlich Pharma AG, Wolhusen, Suíça), no grupo 3 os defeitos críticos foram preenchidos por hidroxiapatita sintética,0,10 gramas, (Alobone poros Osseocon Biomateriais Ltda, Rio de Janeiro/RJ, Brasil) enriquecida com 300 µl da fração mononuclear medular de células tronco na concentração de 1 x 10 6, obtida dos animais doadores de medula, e no grupo 4 os defeitos críticos foram preenchidos por hidroxiapatita bovina, 0,10 gramas, Bio-Oss Small (Bio-Oss® Geistlich Pharma AG, Wolhusen, Suíça) também enriquecida com 300 µl da fração mononuclear medular de células tronco na concentração de 1 x 10 6, obtida dos animais doadores de medula Após oito semanas, os cinco grupos tiveram todos os animais eutanasiados, por intermédio de overdose anestésica de Pentobarbital (180 mg/ kg intraperitoneal). Os grupos, foram submetidos a análises histomorfométrica, preparados corados com tricrômico de Masson, e técnicas imuno-histoquímica de VEGF e Osteopontina. Não existiu diferença estatisticamente significativa entre os grupos 1, 2, 3 e 4, porém existiu entre o grupo controle e os demais grupos que receberam tratamento para regeneração dos defeitos ósseos críticos.


The present study aimed to evaluate the bone regeneration of critical bone defects in the calvaria of rats using xenogenous grafts, Bio-Oss Small (Bio-Oss® Geistlich Pharma AG, Wolhusen, Switzerland) and synthetic hypooxypatite, (Alobone poros Osseocon Biomateriais Ltda., Rio de Janeiro / RJ, Brazil) pure or enriched with the medullary mononuclear fraction of stem cells, in the material and methods: forty young adult male rats, Sprague Dawley, were used, with twelve weeks distributed in five groups with eight animals, being thus named: control group, group 1, group 2, group 3, and group 4. In addition to the forty young adult rats, eight more animals were used as bone marrow donors. The Five groups were submitted to critical size bone defects with 8 (eight) millimeter diameter trephine, in the temporoparietal region. In the control group there was no biomaterial placement, in group 1 the critical size bone defects were filled with synthetic hydroxyapatite, 0,10 grams, (Alobone poros Osseocon Biomateriais Ltda., Rio de Janeiro / RJ, Brazil), in group 2 they were filled with bovine hydroxyapatite,0,10gramas, Bio-Oss Small (Bio-Oss® Geistlich Pharma AG, Wolhusen, Switzerland), in group 3 the critical size bone defects were filled with synthetic hydroxyapatite,0,10 grams, (Alobone poros Osseocon Biomateriais Ltda., Rio de Janeiro / RJ, Brazil) enriched with 300 µl of BMMF containing 1x106 cells, obtained from bone marrow donors animals, and in group 4 the critical size bone defects were filled with bovine hydroxyapatite, 0,10 grams Bio-Oss Small (Bio-Oss® Geistlich Pharma AG, Wolhusen, Switzerland) enriched with 300 µl of BMMF containing 1x106 cells, obtained from bone marrow donors animals. After eight weeks, all five of animals were euthanized by Pentobarbital anesthetic overdose (180 mg / kg intraperitoneal). The groups were submitted to histomorphometric analysis, using Masson's trichrome Stain, and immunohistochemical techniques of VEGF and Osteopontin. There was no statistically significant difference among groups 1, 2, 3 and 4, but it did exist with the control group and the other groups that received treatment for the regeneration of critical bone defects.


Assuntos
Masculino , Cobaias , Ratos , Crânio/lesões , Ratos Sprague-Dawley , Substitutos Ósseos , Células-Tronco Mesenquimais , Aloenxertos , Xenoenxertos
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