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1.
Int J Pharm ; 652: 123765, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38195032

ABSTRACT

Despite the successful use of the radiopharmaceutical radium-223 dichloride ([223Ra]RaCl2) for targeted alpha therapy of castration-resistant prostate cancer patients with bone metastases, some short-term side effects, such as diarrhea and vomiting, have been documented, causing patient discomfort. Hence, we prepared a nanosized micellar solution of [223Ra]RaCl2 and evaluated its biodistribution, pharmacokinetics, and induced biochemical changes in healthy mice up to 96 h after intraperitoneal administration as an alternative to overcome the previous limitations. In addition, we evaluated the bone specificity of micellar [223Ra]RaCl2 in patient-derived xenografts in the osteosarcoma model. The biodistribution studies revealed the high bone-targeting properties of the micellar [223Ra]RaCl2. Interestingly, the liver uptake remained significantly low (%ID/g = 0.1-0.02) from 24 to 96 h after administration. In addition, the micellar [223Ra]RaCl2 exhibited a significantly higher uptake in left (%ID/g = 0.85-0.23) and right (%ID/g = 0.76-0.24) kidneys than in small (%ID/g = 0.43-0.06) and large intestines (%ID/g = 0.24-0.09) over time, suggesting its excretion pathway is primarily through the kidneys into the urine, in contrast to the non-micellar [223Ra]RaCl2. The micellar [223Ra]RaCl2 also had low distribution volume (0.055 ± 0.003 L) and longer elimination half-life (28 ± 12 days). This nanosystem was unable to change the enzymatic activities of alanine aminotransferase, aspartate aminotransferase, gamma GT, glucose, and liquiform lipase in the treated mice. Finally, microscopic examination of the animals' osteosarcoma tumors treated with micellar [223Ra]RaCl2 indicated regression of the tumor, with large areas of necrosis. In contrast, in the control group, we observed tumor cellularity and cell anaplasia, mitotic figures and formation of neoplastic extracellular bone matrix, which are typical features of osteosarcoma. Therefore, our findings demonstrated the efficiency and safety of nanosized micellar formulations to minimize the gastrointestinal excretion pathway of the clinical radiopharmaceutical [223Ra]RaCl2, in addition to promoting regression of the osteosarcoma. Further studies must be performed to assess dose-response outcomes and organ/tissue dosimetry for clinical translation.


Subject(s)
Bone Neoplasms , Osteosarcoma , Prostatic Neoplasms, Castration-Resistant , Humans , Male , Animals , Mice , Radiopharmaceuticals/pharmacokinetics , Tissue Distribution , Renal Elimination , Bone Neoplasms/drug therapy , Bone Neoplasms/radiotherapy , Osteosarcoma/drug therapy , Prostatic Neoplasms, Castration-Resistant/pathology
2.
Rev Bras Ortop (Sao Paulo) ; 58(5): e798-e807, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37908532

ABSTRACT

Objective To reproduce in an animal model the surgical technique of Masquelet used in the treatment of critical bone defects and to analyze the characteristics of the membrane formed around the bone cement. Methods A 10mm critical defect was created in the femoral shaft of 21 Sprague-Dawley rats. After resection of the central portion of the diaphysis, the defect was stabilized with a Kirschner wire introduced through the medullary canal and with the interposition of a bone cement spacer. After 2, 4, and 6 weeks of the surgical procedure, the animals were euthanized and evaluated on radiographs of the posterior limb regarding the size of the defect, alignment and stability of the osteosynthesis. The membranes formed around the spacer were subjected to histological analysis to assess thickness, connective tissue maturation and vascular density. Results Over time, the membranes initially made up of loose connective tissue were replaced by membranes represented by dense connective tissue, rich in thick collagen fibers. At six weeks, membrane thickness was greater (565 ± 208µm) than at four (186.9 ± 70.21µm, p = 0.0002) and two weeks (252.2 ± 55.1µm, p = 0.001). All membranes from the initial time showed foci of osteogenic differentiation that progressively reduced over time. Conclusion In addition to the structural and protective function of the membrane, its intrinsic biological characteristics can actively contribute to bone regeneration. The biological activity attributed by the presence of foci of osteogenesis confers to the membrane the potential of osteoinduction that favors the local conditions for the integration of the bone graft.

3.
Rev. bras. ortop ; 58(5): 798-807, Sept.-Oct. 2023. tab, graf
Article in English | LILACS | ID: biblio-1529933

ABSTRACT

Abstract Objective To reproduce in an animal model the surgical technique of Masquelet used in the treatment of critical bone defects and to analyze the characteristics of the membrane formed around the bone cement. Methods A 10mm critical defect was created in the femoral shaft of 21 Sprague-Dawley rats. After resection of the central portion of the diaphysis, the defect was stabilized with a Kirschner wire introduced through the medullary canal and with the interposition of a bone cement spacer. After 2, 4, and 6 weeks of the surgical procedure, the animals were euthanized and evaluated on radiographs of the posterior limb regarding the size of the defect, alignment and stability of the osteosynthesis. The membranes formed around the spacer were subjected to histological analysis to assess thickness, connective tissue maturation and vascular density. Results Over time, the membranes initially made up of loose connective tissue were replaced by membranes represented by dense connective tissue, rich in thick collagen fibers. At six weeks, membrane thickness was greater (565 ± 208μm) than at four (186.9 ± 70.21μm, p = 0.0002) and two weeks (252.2 ± 55.1μm, p = 0.001). All membranes from the initial time showed foci of osteogenic differentiation that progressively reduced over time. Conclusion In addition to the structural and protective function of the membrane, its intrinsic biological characteristics can actively contribute to bone regeneration. The biological activity attributed by the presence of foci of osteogenesis confers to the membrane the potential of osteoinduction that favors the local conditions for the integration of the bone graft.


Resumo Objetivo Reproduzir em modelo animal a técnica cirúrgica de Masquelet utilizada no tratamento de defeitos ósseos críticos e analisar as características da membrana formada em torno do cimento ósseo. Métodos Um defeito crítico de 10mm foi realizado na diáfise femoral de 21 ratos Sprague-Dawley. Após a ressecção da porção central da diáfise o defeito foi estabilizado com fio de Kirschner introduzido pelo canal medular e com a interposição de espaçador de cimento ósseo. Após 2, 4, e 6 semanas do procedimento cirúrgico os animais foram eutanasiados e avaliados em radiografias do membro posterior quanto ao tamanho do defeito, o alinhamento e a estabilidade da osteossíntese. As membranas formadas em torno do espaçador foram submetidas a análise histológica para avaliação da espessura, da maturação do tecido conjuntivo e da densidade vascular. Resultados Ao longo do tempo as membranas inicialmente constituídas por tecido conjuntivo frouxo foram substituídas por membranas representadas por tecido conjuntivo denso, rico em fibras colágenas espessas. Com seis semanas a espessura das membranas foi maior (565 ± 208μm) do que com quatro (186,9 ± 70,21μm, p = 0,0002) e duas semanas (252,2 ± 55,1μm, p = 0,001). Todas as membranas do tempo inicial apresentaram focos de diferenciação osteogênica que reduziram progressivamente ao longo do tempo. Conclusão Além da função estrutural e protetora da membrana, suas características biológicas intrínsecas podem contribuir ativamente para a regeneração óssea. A atividade biológica atribuída pela presença de focos de osteogênese confere à membrana potencial de osteoindução que favorece as condições locais para a integração do enxerto ósseo.


Subject(s)
Animals , Bone Regeneration , Models, Animal
4.
Bone ; 158: 116018, 2022 05.
Article in English | MEDLINE | ID: mdl-34023543

ABSTRACT

Current xenograft animal models fail to accurately replicate the complexity of human bone disease. To gain translatable and clinically valuable data from animal models, new in vivo models need to be developed that mimic pivotal aspects of human bone physiology as well as its diseased state. Above all, an advanced bone disease model should promote the development of new treatment strategies and facilitate the conduction of common clinical interventional procedures. Here we describe the development and characterisation of an orthotopic humanised tissue-engineered osteosarcoma (OS) model in a recently genetically engineered x-linked severe combined immunodeficient (X-SCID) rat. For the first time in a genetically modified rat, our results show the successful implementation of an orthotopic humanised tissue-engineered bone niche supporting the growth of a human OS cell line including its metastatic spread to the lung. Moreover, we studied the inter- and intraspecies differences in ultrastructural composition of bone and calcified tissue produced by the tumour, pointing to the crucial role of humanised animal models.


Subject(s)
Bone Neoplasms , Osteosarcoma , Animals , Bone Neoplasms/secondary , Bone and Bones/pathology , Cell Line , Cell Line, Tumor , Humans , Osteosarcoma/drug therapy , Rats , Tissue Engineering
5.
Rev Bras Ortop (Sao Paulo) ; 54(4): 408-415, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31435107

ABSTRACT

Objectives To evaluate the factors that influence the outcome of osteosynthesis after closed reduction of the fracture of the femoral neck in young adult patients. Methods A retrospective study was conducted, reviewing the data of patients operated in a large orthopedic hospital from 2003 to 2011; a total of 81 patients met the inclusion criteria. The time interval between the fracture and the surgery, the initial fracture deviation, the quality of the reduction, and the placement of the implant were evaluated. Results The present study observed a strong relationship between the quality of the reduction and therapeutic success. The degree of the initial deviation and the time elapsed between the initial trauma and the osteosynthesis did not influence the surgical outcome regarding bone consolidation. The correct positioning of the implants was associated with a satisfactory evolution in the postoperative period. Conclusion The quality of the reduction and the positioning of the implants are factors that influence the results of osteosynthesis in fractures of the femoral neck in young adult patients.

6.
Rev. bras. ortop ; 54(4): 408-415, July-Aug. 2019. tab, graf
Article in English | LILACS | ID: biblio-1042432

ABSTRACT

Abstract Objectives To evaluate the factors that influence the outcome of osteosynthesis after closed reduction of the fracture of the femoral neck in young adult patients. Methods A retrospective study was conducted, reviewing the data of patients operated in a large orthopedic hospital from 2003 to 2011; a total of 81 patients met the inclusion criteria. The time interval between the fracture and the surgery, the initial fracture deviation, the quality of the reduction, and the placement of the implant were evaluated. Results The present study observed a strong relationship between the quality of the reduction and therapeutic success. The degree of the initial deviation and the time elapsed between the initial trauma and the osteosynthesis did not influence the surgical outcome regarding bone consolidation. The correct positioning of the implants was associated with a satisfactory evolution in the postoperative period. Conclusion The quality of the reduction and the positioning of the implants are factors that influence the results of osteosynthesis in fractures of the femoral neck in young adult patients.


Resumo Objetivos Avaliar os fatores que influenciam o resultado da osteossíntese pela redução fechada da fratura do colo femoral nos pacientes jovens. Métodos Foi feito um estudo retrospectivo com revisão dos dados dos pacientes operados em um hospital ortopédico de grande porte, de 2003 a 2011, com um total de 81 pacientes que atenderam aos critérios de inclusão. O intervalo de tempo entre a fratura e a cirurgia, o desvio inicial da fratura, a qualidade da redução e o posicionamento dos implantes foram os fatores avaliados. Resultados O estudo encontrou forte relação entre a qualidade da redução e o sucesso terapêutico. O grau de desvio inicial e o tempo entre o trauma inicial e a osteossíntese não influenciaramo desfecho cirúrgico emrelação à consolidação óssea. O correto posicionamento dos implantes mostrou relação com a evolução satisfatória no pós-operatório dos pacientes. Conclusão A qualidade da redução e o posicionamento dos implantes são fatores que influenciamoresultadodaosteossíntesenafraturadocolodofêmurnopacienteadultojovem.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Pseudarthrosis , Femoral Neck Fractures , Femur Head Necrosis , Femur Neck
7.
Int Orthop ; 43(5): 1205-1213, 2019 05.
Article in English | MEDLINE | ID: mdl-29948010

ABSTRACT

OBJECTIVE: Percutaneous fixation of the acetabulum is a treatment option for select acetabular fractures. Intra-operative fluoroscopy is required, and despite various described imaging strategies, it is debatable as to which combination of fluoroscopic views provides the most accurate and reliable assessment of screw position. MATERIALS AND METHODS: Using five synthetic pelvic models, an experimental setup was created in which the anterior acetabular columns were instrumented with screws in five distinct trajectories. Five fluoroscopic images were obtained of each model (Pelvic Inlet, Obturator Oblique, Iliac Oblique, Obturator Oblique/Outlet, and Iliac Oblique/Outlet). The images were presented to 32 pelvic and acetabular orthopaedic surgeons, who were asked to draw two conclusions regarding screw position: (1) whether the screw was intra-articular and (2) whether the screw was intraosseous in its distal course through the bony corridor. RESULTS: In the assessment of screw position relative to the hip joint, accuracy of surgeon's response ranged from 52% (iliac oblique/outlet) to 88% (obturator oblique), with surgeon confidence in the interpretation ranging from 60% (pelvic inlet) to 93% (obturator oblique) (P < 0.0001). In the assessment of intraosseous position of the screw, accuracy of surgeon's response ranged from 40% (obturator oblique/outlet) to 79% (iliac oblique/outlet), with surgeon confidence in the interpretation ranging from 66% (iliac oblique) to 88% (pelvic inlet) (P < 0.0001). CONCLUSIONS: The obturator oblique and obturator oblique/outlet views afforded the most accurate and reliable assessment of penetration into the hip joint, and intraosseous position of the screw was most accurately assessed with pelvic inlet and iliac oblique/outlet views. EVIDENCE: Clinical Question.


Subject(s)
Acetabulum/diagnostic imaging , Acetabulum/surgery , Bone Screws , Fracture Fixation, Internal/methods , Fractures, Bone/diagnostic imaging , Fractures, Bone/surgery , Pelvic Bones/diagnostic imaging , Acetabulum/injuries , Fluoroscopy , Fracture Fixation, Internal/instrumentation , Humans , Intraoperative Care , Models, Anatomic , Pelvis/diagnostic imaging , Surgeons
8.
Rev Bras Parasitol Vet ; 25(4): 450-458, 2016.
Article in English | MEDLINE | ID: mdl-27925060

ABSTRACT

This study describes the occurrence of dogs naturally co-infected with Hepatozoon canis and two Leishmania species: L. infantum or L. braziliensis. Four dogs serologically diagnosed with Visceral Leishmaniasis were euthanized. Liver and spleen samples were collected for histopathological analysis and DNA isolation. H. canis meronts were observed in tissues from all four dogs. H. canis infection was confirmed by PCR followed by sequencing of a fragment of 18S rRNA gene. Leishmania detection and typing was confirmed by ITS1' PCR-RFLP and parasite burden was calculated using ssrRNA quantitative qPCR. A DPP - Dual Path platform test was performed. One out (Dog #2) of four animals was asymptomatic. Dogs #1 and #4 were infected by L. infantum and were DPP test positive. Dogs #2 and #3 were infected by L. braziliensis and were DPP test negative. Furthermore, visceral dissemination was observed in Dogs #2 and #3, since L. braziliensis was detected in liver and spleen samples. The visceral dissemination of L. braziliensis associated with systemic signs suggested that this co-infection could influence the parasite burden and disease progression.


Subject(s)
Coccidiosis/veterinary , Coinfection/veterinary , Dog Diseases/parasitology , Leishmaniasis, Visceral/veterinary , Animals , Coccidia , Coccidiosis/parasitology , Coinfection/parasitology , Dogs , Leishmania infantum , Leishmaniasis, Visceral/parasitology , Polymorphism, Restriction Fragment Length
9.
Rev. bras. parasitol. vet ; 25(4): 450-458, Sept.-Dec. 2016. tab, graf
Article in English | LILACS | ID: biblio-830049

ABSTRACT

Abstract This study describes the occurrence of dogs naturally co-infected with Hepatozoon canis and two Leishmania species: L. infantum or L. braziliensis. Four dogs serologically diagnosed with Visceral Leishmaniasis were euthanized. Liver and spleen samples were collected for histopathological analysis and DNA isolation. H. canis meronts were observed in tissues from all four dogs. H. canis infection was confirmed by PCR followed by sequencing of a fragment of 18S rRNA gene. Leishmania detection and typing was confirmed by ITS1' PCR-RFLP and parasite burden was calculated using ssrRNA quantitative qPCR. A DPP - Dual Path platform test was performed. One out (Dog #2) of four animals was asymptomatic. Dogs #1 and #4 were infected by L. infantum and were DPP test positive. Dogs #2 and #3 were infected by L. braziliensis and were DPP test negative. Furthermore, visceral dissemination was observed in Dogs #2 and #3, since L. braziliensis was detected in liver and spleen samples. The visceral dissemination of L. braziliensis associated with systemic signs suggested that this co-infection could influence the parasite burden and disease progression.


Resumo O presente estudo descreve a ocorrência de coinfecção com Hepatozoon canis e duas espécies de Leishmania (L. infantum ou L. braziliensis) em cães. Quatro cães sorologicamente diagnosticados com leishmaniose visceral foram eutanasiados. Amostras do baço e fígado foram submetidas à histopatologia e extração de DNA. Merontes de H. canis foram observados nos quatro cães. A infecção por H. canis foi confirmada por PCR e sequenciamento de um fragmento do gene 18S rRNA. A infecção por Leishmania e tipagem foram realizadas por PCR-RFLP do região intergênica ITS1. A carga parasitária foi calculada pela qPCR quantitativa baseada no gene ssrRNA. O teste DPP - Dual Path platform foi realizado. Apenas o Cão #2 era assintomático. Os cães #1 e #4 estavam infectados com L. infantum e foram positivos no DPP. Os cães #2 e #3 estavam infectados com L. braziliensis e foram negativos no DPP. Além disso, visceralização foi observada nos cães #2 e #3, nos quais L. braziliensis foi detectada em amostras de baço e fígado. A visceralização da L. braziliensis associada a sinais clínicos sistêmicos sugerem que esta coinfecção pode ter influenciado na carga parasitária e progressão da doença.


Subject(s)
Animals , Dogs , Coccidiosis/veterinary , Dog Diseases/parasitology , Coinfection/veterinary , Leishmaniasis, Visceral/veterinary , Polymorphism, Restriction Fragment Length , Coccidia , Coccidiosis/parasitology , Leishmania infantum , Coinfection/parasitology , Leishmaniasis, Visceral/parasitology
10.
Rev Bras Ortop ; 51(4): 459-65, 2016.
Article in English | MEDLINE | ID: mdl-27517027

ABSTRACT

OBJECTIVE: Giant cell tumors are benign bone neoplasms that are relatively rare in adults and their biological behavior is still unpredictable. The incidence of local recurrence has presented variation between 0% and 65% in studies conducted worldwide, but few data are available on this complication in the Brazilian population. METHODS: Information on 155 patients with confirmed histological diagnoses of giant cell tumor who were treated in our institution's orthopedic oncology service between January 2000 and July 2014 was gathered. Demographic characteristics were evaluated and compared between patients who presented local recurrence during the clinical follow-up. RESULTS: Local recurrence was observed in 26 patients (16.7%), of whom 22 were female (84.6%). The most common site of local recurrence was the distal femur (38.4%). Eleven patients presented early recurrence, while 15 cases were diagnosed after 15 months, representing 42.3% and 57.7%, respectively. Metastases were identified in five patients (3.2%). CONCLUSION: Tumor-related factors did not show any increased incidence of local recurrence of giant cell tumors. Surgical treatment with an intralesional margin is a valid option for treating local recurrences and does not show any difference in disease-free survival in relation to other types of procedures. Clinical treatment is reserved for cases of unresectable tumors or when surgical treatment is impossible.


OBJETIVOS: O tumor de células gigantes (TCG) é uma neoplasia óssea benigna relativamente rara em adultos, porém seu comportamento biológico ainda é imprevisível. A incidência de recidiva local apresenta variação entre 0­65% em estudos internacionais, porém há poucos dados referentes a essa complicação em nossa população. MÉTODOS: Foram coletadas informações sobre 155 pacientes com diagnóstico histológico confirmado de TCG, acompanhados no serviço de oncologia ortopédica da nossa instituição, de janeiro de 2000 a julho de 2014. As características demográficas foram avaliadas e comparadas entre os pacientes que apresentaram recidiva local durante o seguimento clínico. RESULTADOS: Houve recidiva local em 26 pacientes (16,7%), dos quais 22 eram do sexo feminino (84,6%). A localização mais comum de recidiva local foi o fêmur distal (38,4%). Onze pacientes apresentaram recidiva precoce, enquanto 15 casos foram diagnosticados após 15 meses, o que representa, respectivamente, 42,3% e 57,7%. Metástases foram identificadas em cinco pacientes (3,2%). CONCLUSÃO: Os fatores relacionados ao tumor não evidenciaram aumento da incidência de recidiva local de tumor de células gigantes. O tratamento cirúrgico com margem intralesional é uma opção válida no tratamento de recidivas locais e não apresenta diferença de sobrevida livre de doença entre outros tipos de procedimentos. Tratamento clínico é reservado em casos de tumores irressecáveis ou impossibilidade de tratamento cirúrgico.

11.
Rev. bras. ortop ; 51(4): 459-465, July-Aug. 2016. tab, graf
Article in English | LILACS | ID: lil-792739

ABSTRACT

ABSTRACT OBJECTIVE: Giant cell tumors are benign bone neoplasms that are relatively rare in adults and their biological behavior is still unpredictable. The incidence of local recurrence has presented variation between 0% and 65% in studies conducted worldwide, but few data are available on this complication in the Brazilian population. METHODS: Information on 155 patients with confirmed histological diagnoses of giant cell tumor who were treated in our institution's orthopedic oncology service between January 2000 and July 2014 was gathered. Demographic characteristics were evaluated and compared between patients who presented local recurrence during the clinical follow-up. RESULTS: Local recurrence was observed in 26 patients (16.7%), of whom 22 were female (84.6%). The most common site of local recurrence was the distal femur (38.4%). Eleven patients presented early recurrence, while 15 cases were diagnosed after 15 months, representing 42.3% and 57.7%, respectively. Metastases were identified in five patients (3.2%). CONCLUSION: Tumor-related factors did not show any increased incidence of local recurrence of giant cell tumors. Surgical treatment with an intralesional margin is a valid option for treating local recurrences and does not show any difference in disease-free survival in relation to other types of procedures. Clinical treatment is reserved for cases of unresectable tumors or when surgical treatment is impossible.


RESUMO OBJETIVOS: O tumor de células gigantes (TCG) é uma neoplasia óssea benigna relativamente rara em adultos, porém seu comportamento biológico ainda é imprevisível. A incidência de recidiva local apresenta variação entre 0-65% em estudos internacionais, porém há poucos dados referentes a essa complicação em nossa população. MÉTODOS: Foram coletadas informações sobre 155 pacientes com diagnóstico histológico confirmado de TCG, acompanhados no serviço de oncologia ortopédica da nossa instituição, de janeiro de 2000 a julho de 2014. As características demográficas foram avaliadas e comparadas entre os pacientes que apresentaram recidiva local durante o seguimento clínico. RESULTADOS: Houve recidiva local em 26 pacientes (16,7%), dos quais 22 eram do sexo feminino (84,6%). A localização mais comum de recidiva local foi o fêmur distal (38,4%). Onze pacientes apresentaram recidiva precoce, enquanto 15 casos foram diagnosticados após 15 meses, o que representa, respectivamente, 42,3% e 57,7%. Metástases foram identificadas em cinco pacientes (3,2%). CONCLUSÃO: Os fatores relacionados ao tumor não evidenciaram aumento da incidência de recidiva local de tumor de células gigantes. O tratamento cirúrgico com margem intralesional é uma opção válida no tratamento de recidivas locais e não apresenta diferença de sobrevida livre de doença entre outros tipos de procedimentos. Tratamento clínico é reservado em casos de tumores irressecáveis ou impossibilidade de tratamento cirúrgico.


Subject(s)
Humans , Male , Female , Epidemiology , Giant Cell Tumors , Recurrence
12.
Rev. bras. ortop ; 51(1): 70-74, Jan.-Feb. 2016. tab, graf
Article in Portuguese | LILACS | ID: lil-775652

ABSTRACT

This study evaluated in vitro differentiation of mesenchymal stromal cells isolated from bone marrow, in tenocytes after treatment with bovine tendon extract. METHODS: Bovine tendons were used for preparation of the extract and were stored at -80 °C. Mesenchymal stromal cells from the bone marrow of three donors were used for cytotoxicity tests by means of MTT and cell differentiation by means of qPCR. RESULTS: The data showed that mesenchymal stromal cells from bone marrow treated for up to 21 days in the presence of bovine tendon extract diluted at diminishing concentrations (1:10, 1:50 and 1:250) promoted activation of biglycan, collagen type I and fibromodulin expression. CONCLUSION: Our results show that bovine tendon extract is capable of promoting differentiation of bone marrow stromal cells in tenocytes.


O estudo avalia a diferenciação in vitro das células mesenquimais isoladas do estroma da medula óssea em tenócitos após tratamento com extrato de tendão bovino. MÉTODOS: Tendões bovinos foram usados para confecção do extrato e estocados a -80 °C. Células mesenquimais do estroma da medula óssea (BMSCs) de três doadores foram usadas para os testes de citotoxicidade por MTT e diferenciação celular por qPCR. RESULTADOS: Os dados mostram que células mesenquimais do estroma da medula óssea tratadas por até 21 dias em presença do extrato de tendão bovino diluído em concentrações crescentes (1:10, 1:50 e 1:250) promovem a ativação da expressão de biglican, colágeno tipo I e fibromodulina. CONCLUSÃO: Nossos resultados mostram que o extrato de tendão bovino é capaz de promover a diferenciação das BMSCs em tenócitos.


Subject(s)
Animals , Cattle , Bone Marrow , Mesenchymal Stem Cells , Tendons
13.
BMC Vet Res ; 10: 36, 2014 Feb 05.
Article in English | MEDLINE | ID: mdl-24495743

ABSTRACT

BACKGROUND: The repair of large bone defects is a major orthopedic challenge because autologous bone grafts are not available in large amounts and because harvesting is often associated with donor-site morbidity. Considering that bone marrow stromal cells (BMSC) are responsible for the maintenance of bone turnover throughout life, we investigated bone repair at a site of a critically sized segmental defect in sheep tibia treated with BMSCs loaded onto allografts. The defect was created in the mid-portion of the tibial diaphysis of eight adult sheep, and the sheep were treated with ex-vivo expanded autologous BMSCs isolated from marrow aspirates and loaded onto cortical allografts (n = 4). The treated sheep were compared with control sheep that had been treated with cell-free allografts (n = 4) obtained from donors of the same breed as the receptor sheep. RESULTS: The healing response was monitored by radiographs monthly and by computed tomography and histology at six, ten, fourteen, and eighteen weeks after surgery. For the cell-loaded allografts, union was established more rapidly at the interface between the host bone and the allograft, and the healing process was more conspicuous. Remodeling of the allograft was complete at 18 weeks in the cell-treated animals. Histologically, the marrow cavity was reestablished, with intertrabecular spaces being filled with adipose marrow and with evidence of focal hematopoiesis. CONCLUSIONS: Allografts cellularized with AOCs (allografts of osteoprogenitor cells) can generate great clinical outcomes to noncellularized allografts to consolidate, reshape, structurally and morphologically reconstruct bone and bone marrow in a relatively short period of time. These features make this strategy very attractive for clinical use in orthopedic bioengineering.


Subject(s)
Bone Transplantation/veterinary , Mesenchymal Stem Cell Transplantation/veterinary , Mesenchymal Stem Cells/physiology , Sheep , Animals , Bone Diseases/surgery , Bone Regeneration , Hindlimb/surgery
14.
Rio de Janeiro; s.n; 2014. xxiii,136 p. ilus, tab, graf, mapas.
Thesis in Portuguese | LILACS | ID: lil-774295

ABSTRACT

A Leishmaniose Visceral causada pela Leishmania infantum é uma doença zoonótica no Novo Mundo em que o cão é o principal hospedeiro doméstico. O conhecimento prévio dos mecanismos imunopatogênicos associados à infecção porL. infantum é necessário para o desenvolvimento de vacinas e outras estratégias decontrole. O objetivo geral desta tese foi correlacionar a expressão clínica, a cargaparasitária, a resposta imunológica do hospedeiro e a diversidade genética dosparasitos em cães naturalmente infectados por L. infantum. O presente estudo éuma avaliação transversal de noventa e dois cães naturalmente infectados por L.infantum provenientes do estado do Mato Grosso. A infecção dos animais incluídosno estudo foi confirmada por sorologia, cultura e /ou PCR. O diagnóstico etiológicofoi realizado por PCR-RFLP para o gene hsp70 e por eletroforese de enzimas nosparasitos isolados. Foram ainda analisados os sinais clínicos, a resposta imune pelaexpressão gênica de citocinas, a carga parasitária por qPCR, as alteraçõeshistológicas no baço e fígado e a as populações e genótipos de L. infantumcirculantes por meio da análise do polimorfismo de microssatélites. Foram definidosgrupos de acordo com a carga parasitária esplênica e hepática. Os animais com altacarga parasitária apresentaram altos títulos de anticorpos específicos antiLeishmaniae mais sinais clínicos da doença. A carga parasitária no baço foi maiordo que no fígado e houve correlação com o rompimento da arquitetura esplênica,caracterizado principalmente pela desorganização da polpa branca. No fígado, acarga parasitária foi correlacionada positivamente à ocorrência de granulomas, àdegeneração dos hepatócitos bem como à intensidade do infiltrado inflamatório.Mostramos que a maior carga parasitária promoveu menor expressão gênica de IL-12, IFNgama, TNF, IL-6, TGFbeta e IL-10 no baço e maior expressão de CCL2, CXCL8 eMAP4K4 no fígado...


Visceral leishmaniasis is a zoonotic disease in the New World and the domestic dogis the main host of Leishmania infantum. Prior knowledge of the immunopathogenicmechanisms associated with infection by L. infantum is required for the developmentof vaccines and other control strategies. The overall aim of this thesis was tocompare the clinical expression, parasite load, the host immune response andgenetic diversity of parasites in dogs naturally infected with L. infantum. This study isa cross-sectional assessment of ninety-two dogs naturally infected by L. infantum.Infection was confirmed by serology, parasite culture and / or PCR. The etiology wasassessed by hsp70 PCR-RFLP and MLEE. We further analyzed clinical signs,immune response by cytokine gene expression, molecular parasite load by qPCR,histological changes in splenic and hepatic compartments and also L. infantumpopulations and genotypes through microsatellite analysis. Groups according to thespleen and liver parasite load were defined. Animals with high parasite load had hightiters of anti-Leishmania antibodies and more clinical signs. The parasite load in thespleen was higher than in liver and correlated with disruption of splenic architecture,mainly characterized by white pulp disorganization. Liver parasite load wascorrelated with the occurrence of granulomas, degeneration and intensity of theinflammatory infiltrate. We show that the higher parasite load promoted lower geneexpression of IL-12, IFN gama, TNF, IL-6, IL-10 and TGF beta in the spleen and increasedexpression of CCL2, CXCL8 MAP4K4 in the liver. Genetic analysis of parasites isindicative of polyclonal infection and tissue tropism of some clones, more evident inthe analysis of paired samples (strain isolated and tissue)...


Subject(s)
Dogs , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Visceral/immunology , Parasite Load , Immunity, Mucosal , Serologic Tests
15.
Biomed Res Int ; 2013: 790842, 2013.
Article in English | MEDLINE | ID: mdl-23710460

ABSTRACT

Bone marrow stromal cells (BMSCs) are a valuable resource for skeletal regenerative medicine because of their osteogenic potential. In spite of the very general term "stem cell," this population of cells is far from homogeneous, and different BMSCs clones have greatly different phenotypic properties and, therefore, potentially different therapeutic potential. Adherence to a culture flask surface is a primary defining characteristic of BMSCs. We hypothesized that based on the adherence time we could obtain an enriched population of cells with a greater therapeutic potential. We characterized two populations of bone marrow-derived cells, those that adhered by three days (R-cells) and those that did not adhere by three days but did by six days (L-cells). Clones derived from L-cells could be induced into adipogenic, chondrogenic, and osteogenic differentiation in vitro. L-cells appeared to have greater proliferative capacity, as manifested by larger colony diameter and clones with higher CD146 expression. Only clones from L-cells developed bone marrow stroma in vivo. We conclude that the use of late adherence of BMSCs is one parameter that can be used to enrich for cells that will constitute a superior final product for cell therapy in orthopedics.


Subject(s)
Cell Adhesion/genetics , Cell Differentiation , Mesenchymal Stem Cells/cytology , Osteogenesis , Stem Cell Niche , Adult , CD146 Antigen/biosynthesis , Cell Lineage/genetics , Cells, Cultured , Female , Fibroblasts/cytology , Gene Expression Regulation , Humans , Male , Middle Aged , Regenerative Medicine
16.
Rev. Soc. Bras. Med. Trop ; 44(6): 771-773, Nov.-Dec. 2011. ilus
Article in English | LILACS | ID: lil-611760

ABSTRACT

INTRODUCTION: Visceral leishmaniasis presents urban behavior in some Brazilian cities, with domestic dogs as the main infection source. In Cuiabá, MT, canine visceral leishmaniasis was diagnosed and characterized as recommended by the Ministry of Health. METHODS: Biological samples from suspected canine carriers were analyzed by the isoenzyme electrophoresis technique. The 6PGDH enzyme and reference strain IOC/L0566 (MHOM/BR/1975/M2903) of Leishmania (Leishmania) infantum was used as one of the controls. RESULTS: Electrophoresis analysis revealed that the canine isolates belonged to the species L. (L.) infantum. CONCLUSIONS: The authors emphasize the importance of species characterization, particularly in areas of mixed infection like Cuiabá.


INTRODUÇÃO: A leishmaniose visceral apresenta comportamento urbano em algumas cidades brasileiras, sendo os cães domésticos as principais fontes de infecção. Em Cuiabá-MT, a leishmaniose visceral canina foi diagnosticada e caracterizada, como recomendação do Ministério da Saúde. MÉTODOS: Amostras biológicas de cães suspeitos foram analisadas por eletroforese de isoenzimas. Foram utilizadas a enzima 6PGDH e a cepa de referência IOC/L0566 (MHOM/BR/1975/M2903) de Leishmania (Leishmania) infantum, como um dos controles. RESULTADOS: A análise eletroforética revelou que os isolados pertenciam à espécie L. (L.) infantum. CONCLUSÕES: Os autores ressaltam a importância da caracterização da espécie, principalmente em cidades com infecção mista, como Cuiabá.


Subject(s)
Animals , Dogs , Dog Diseases/parasitology , Leishmania infantum/isolation & purification , Leishmaniasis, Visceral/veterinary , Brazil/epidemiology , Dog Diseases/diagnosis , Dog Diseases/epidemiology , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Visceral/parasitology , Prevalence , Urban Population
17.
Rev Soc Bras Med Trop ; 44(6): 771-3, 2011.
Article in English | MEDLINE | ID: mdl-22231252

ABSTRACT

INTRODUCTION: Visceral leishmaniasis presents urban behavior in some Brazilian cities, with domestic dogs as the main infection source. In Cuiabá, MT, canine visceral leishmaniasis was diagnosed and characterized as recommended by the Ministry of Health. METHODS: Biological samples from suspected canine carriers were analyzed by the isoenzyme electrophoresis technique. The 6PGDH enzyme and reference strain IOC/L0566 (MHOM/BR/1975/M2903) of Leishmania (Leishmania) infantum was used as one of the controls. RESULTS: Electrophoresis analysis revealed that the canine isolates belonged to the species L. (L.) infantum. CONCLUSIONS: The authors emphasize the importance of species characterization, particularly in areas of mixed infection like Cuiabá.


Subject(s)
Dog Diseases/parasitology , Leishmania infantum/isolation & purification , Leishmaniasis, Visceral/veterinary , Animals , Brazil/epidemiology , Dog Diseases/diagnosis , Dog Diseases/epidemiology , Dogs , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Visceral/parasitology , Prevalence , Urban Population
18.
Rev. bras. ciênc. vet ; 16(3): 119-123, 2009.
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1491394

ABSTRACT

Foram avaliadas quatro técnicas de sincronização da onda folicular em protocolos de superovulação. Para tal, foram utilizadas 112 vacas doadoras, das raças Simental, Limousin e Red Angus, com escore corporal médio de 3,0. Os animais foram divididos aleatoriamente em cinco grupos experimentais de acordo com o método de sincronização da emergência da onda folicular. Foram realizadas 30 superovulações em cada grupo, considerando os seguintes protocolos: GI - grupo controle – animais superovulados entre o 8o e o 12o dia do ciclo estral (dia zero = estro); GII – animais que sofreram punção folicular no 9o dia (dia 0 = estro) e início do tratamento superovulatório no 11o dia; GIII – animais que sofreram punção folicular em fase não conhecida do ciclo estral, associada ao uso de um dispositivo intravaginal contendo progesterona (P4) e tratamento superovulatório iniciado 48h após a punção, GIV – animais que utilizaram implante intravaginal de progesterona colocadoem fase aleatória do ciclo estral, mantido por nove dias, associado à administração de 50 mg de P4 e de 2mg de benzoato de estradiol, sendo o tratamento superovulatório iniciado cinco dias após a colocação do dispositivo e GV – animais que receberam implante intravaginal de P4 colocado em fase aleatória do ciclo estral e mantido por oito dias, associado à administração de 50mg de P4 e 2mg de 17â-estradiol, sendo o tratamento superovulatório iniciado quatro dias após a colocação do dispositivo. Nos grupos I, II, III, IV e V o total de estruturas coletadas e de embriões viáveis foram, respectivamente (13,53±9,23 vs 13,87 ± 7,85 vs 18,70 ± 10,88 vs 9,03 ± 4,97 vs 13,60 ± 8,39) e (8,43±5,68 vs 8,27 ± 7,06 vs 10,47 ± 8,19 vs 5,37 ± 2,92 vs 7,23 ± 5,30). Os resultados observados no GIII foram superiores ao GI, GII, GIV e GV (P 0,05), enquanto o desempenho de GIV foi inferior (P<0,05). Os resultados permitem concluir que é possível sincronizar a emergência da onda folicular de vacas doadoras, com início da superovulação em qualquer momento do ciclo estral, e que o tratamento progestágeno associado à punção folicular oferece os melhores resultados.


We evaluated four different techniques of follicular wave synchronization by comparing total number of structures recovery, number of viable and degenerated embryos, number of oocytes recovery and cost of uterine flushing. One hundred twelve Simental, Limousin and Red Angus donators were randomly allocated in five treatment groups according to protocol used for follicular wave emergence synchronization. Thirty superovulations were performed in each group, the programs were: G1- Control, superovulation treatment between days 8 and 12 of the estrous cycle; G2- follicle aspiration on day 9 of the estrous cycle; G3- follicle aspiration plus intravaginal progesterone implant; G4- intravaginal progesterone implant plus estradiol benzoate and G5- intravaginal progesterone implant plus estradiol-17â. Artificial insemination was performed twice, 12 and 24 hours after detection of behavioral estrus. Embryo collection was performed on day 7 after inseminations. Total number of recovered structures (18,70 ± 10,88 vs 13,53 ± 9,23) and viable embryos (10,47 ± 8,19 vs 8,43 ± 5,68) were higher (P0,05) were detected amongst groups 2, 5 and 1, while performance of G4 was the lowest (P<0,05). Results demonstrate to be possible synchronize follicular wave emergence by initiating superstimulation at any time of the estrous cycle. Additionally we verified that the program using progesterone associated to follicular ablation had the best results in synchronizing follicular wave emergence aiming superstimulation in cattle.


Subject(s)
Female , Animals , Cattle , Follicular Phase/metabolism , Superovulation/genetics , Cattle/classification , Hormones , Biological Treatment/methods
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