Efeito modulador da estratégia vacinal BCG/DNAhsp65 na encefalite autoimune experimental(EAE)

Tanto o BCG (Bacilo de Calmette-Guérin) quanto a DNAhsp65 são vacinas contra tuberculose, porém além da atividade protetora desejável ambas apresentam atividade imunomoduladora. Seguindo a linha de pesquisa de nosso laboratório que investiga a atividade da DNAhsp65 sobre doenças autoimunes, avaliamos o efeito da associação destas vacinas sob a forma de uma estratégia vacinal tipo prime-boost (priming com BCG seguida de booster com DNAhsp65), sobre o desenvolvimento da Encefalite Autoimune Experimental (EAE), que é modelo animal de esclerose múltipla. Ratos Lewis fêmeas foram divididos em grupos de 5 a 6 animais (salina, BCG, EAE, BCG/EAE, BCG/vetor/EAE e BCG/vacina/EAE) e imunizados em intervalos de 15 dias. Os animais receberam um primming com 2 - 10 x 105 unidades formadoras de colônias de BCG subcutâneo seguido de dois boosters com 300 g de pVAXhsp65 numa solução de sacarose 25% por via intramuscular. A EAE foi induzida 15 dias após a última imunização, por inoculação de 25 g de proteína básica de mielina (MBP) associada ao Adjuvante Completo de Freund contendo Mycobacterium butyricum. Aqueles que não receberam os inóculos descritos foram injetados com salina, exceto o grupo BCG/vetor/EAE que recebeu 300 g de pVAX (vetor plasmidial vazio) também em solução de sacarose. Os animais foram acompanhados diariamente até serem submetidos à eutanásia, 3 semanas mais tarde, durante a fase de recuperação da doença para avaliação da resposta imune, escore clínico e presença de infiltrado inflamatório no SNC. A evolução clínica da EAE foi similar entre animais vacinados e não vacinados, mas a análise histopatológica revelou que a imunização prévia com BCG ou BCG/DNAhsp65 diminui o processo inflamatório. No cérebro foi observada redução acentuada do processo inflamatório nos grupos BCG/EAE, ...(Resumo completo, clicar acesso eletrônico abaixo)

Validação de uma câmara para exposição experimental a vapores, pela via respiratória, pelo sistema nose only exposure system

A exposição experimental a vapores de solventes pela via respiratória pode ser realizada em câmaras de dois tipos: a que expõe todo o animal por imersão na atmosfera experimental e aquela em que a exposição se dá apenas pelo nariz. O sistema para exposição apenas pelo nariz, denominado de NOES- Nose Only Exposure System, tem as vantagens de utilizar menos material, ter uma atmosfera continuamente renovada, produzir exposição mais uniforme entre os animais, ser mais facilmente controlado e evitar a penetração dos solventes por outras vias. A desvantagem está no fato na restrição do tempo do experimento por provocar estresse ao animal. O projeto experimental consistiu na validação de uma câmara de exposição para ratos, do tipo NOES, dotada de 44 portas, através da avaliação da homogeneidade e da estabilidade das concentrações de voláteis na atmosfera a ser inalada, utilizando etanol combustível como agente químico para os testes. Os resultados indicaram que a variabilidade das concentrações entre os planos da câmara (portas da camada superior e inferior), entre portas de exposição e, também, entre as médias apuradas para cada tempo não diferem expressivamente entre si. Assim, pode-se considerar que o equipamento mostrou-se adequado para manter a homogeneidade e a estabilidade das concentrações durante as 6 horas de experimentação, para o etanol combustível

Concentrações séricas e peritoneal de proteínas de fase aguda em equinos submetidos à endotoxemia experimental, tratados ou não com lidocaína

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Modelo experimental de conjuntivite alérgica: efeito do tratamento farmacológico com a proteína anti-inflamatória galectina - 1

Pós-graduação em Genética - IBILCE

Processo de reparo ósseo diante de três tipos de superfície de titânio: análise histomorfométrica e por microscopia eletrônica de varredura associada ao EDS: estudo experimental

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Interferência do parecoxibe sobre a função renal e lesão de rins submetidos ao estresse isquêmico: trabalho experimental em ratos com uso de NGAL como marcador da função renal

Pós-graduação em Anestesiologia - FMB

Avaliação histopatológica da cápsula posterior associada ao implante intraocular com superfície modificada: estudo experimental em coelhos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Deproteinized Bovine Bone Mineral or Autologous Bone at Dehiscence Type Defects at Implants Installed Immediately into Extraction Sockets: An Experimental Study in Dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Host responses induced by different animal models of periodontal disease: a literature review

Periodontitis is an infectious disease characterized by chronic inflammation of the periodontium, and it is mediated and modulated by the host immune system. In the presence of microorganisms or other antigens, immune cells (macrophages/monocytes, dendritic cells, lymphocytes, neutrophils), endothelial cells and fibroblasts secrete cytokines and trigger immune and inflammatory reactions. However, when synthesized at high levels, cytokines modify the pattern of cellular response, participating substantially in the development of chronic inflammatory pathologies, such as periodontal disease. Understanding the origin and progression of bone resorption is one of the primary goals of the field of periodontics, aiming to arrest the disease progression and to optimize future treatments. For this purpose, the development of experimental models is an important and necessary step before entering into clinical trials with new therapies. The purpose of this study is to characterize/evaluate the tissue changes induced by various models of experimental periodontitis through a literature review.

Estudo da migração de células peritoneais na paracoccidioidomicose experimental murina: avalaição do efeito da estimulaçao de células peritoneais por lectina sobra a evolução da lesão paracoccidióidica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Treatment with vitamin D/MOG association suppresses experimental autoimmune encephalomyelitis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Dimensional changes in soft tissues around dental implants following free gingival grafting: an experimental study in dogs

ObjectiveTo study the buccal dimensional tissue changes at oral implants following free gingival grafting, with or without including the keratin layer, performed at the time of implant installation into alveolar mucosa.Material and methodsThe mandibular premolars and first molars were extracted bilaterally in six Beagle dogs. In the right side of the mandible (Test), flaps were first elevated, and the buccal as well as part of the lingual masticatory mucosa was removed. An incision of the periosteum at the buccal aspect was performed to allow the flap to be coronally repositioned. Primary wound closure was obtained. In the left side, the masticatory (keratinized) mucosa was left in situ, and no sutures were applied (Control). After 3months of healing, absence of keratinized mucosa was confirmed at the test sites. Two recipient sites were prepared at each side of the mandible in the region of the third and fourth premolars. All implants were installed with the shoulder placed flush with the buccal alveolar bony crest, and abutments were connected to allow a non-submerged healing. Two free gingival mucosal grafts were harvested from the buccal region of the maxillary canines. One graft was left intact (gingival mucosal graft), while for the second, the epithelial layer was removed (gingival connective tissue graft). Subsequently, the grafts were fixed around the test implants in position of the third and fourth premolars, respectively. After 3months, the animals were euthanized and ground sections obtained.ResultsSimilar bony crest resorption and coronal extension of osseointegration were found at test and control sites. Moreover, similar dimensions of the peri-implant soft tissues were obtained at test and control sites.ConclusionsThe increase in the alveolar mucosal thickness by means of a gingival graft affected the peri-implant marginal bone resorption and soft tissue recession around implants. This resulted in outcomes that were similar to those at implants surrounded by masticatory mucosa, indicating that gingival grafting in the absence of keratinized mucosa around implants may reduce the resorption of the marginal crest and soft tissue recession.

Influence of bone marrow on osseointegration in long bones: an experimental study in sheep

Aim To evaluate the influence of yellow bone marrow on osseointegration of titanium oral implants using a long bone model.Material and methodsThe two tibiae of eight sheep were used as experimental sites. Two osteotomies for implant installation were prepared in each tibia. At the control sites, no further treatments were performed while, at the test sites, bone marrow was removed from the osteotomy site with a curette to an extent that exceeded the implant dimensions. As a result, the apical portion of the implants at the control sites was in contact with bone marrow while, at the test sites, it was in contact with the blood clot. After 2months, the same procedures were performed in the contralateral side. After another month, the animal was sacrificed. Ground sections were obtained for histological analysis.ResultsAfter 1month of healing, no differences between test and control sites were found in the apical extension of osseointegration and the percentage of new bone-to-implant contact. However, after 3months of healing, a higher percentage of new bone-to-implant contact was found at the test compared to the control sites in the marrow compartment. The apical extension of osseointegration, however, was similar to that found at the 1-month healing period both for test and control sites.ConclusionsOsseointegration appeared to be favored by the presence of a blood clot when compared to the presence of yellow fatty bone marrow. Moreover, the contact with cortical bone appeared to be a prerequisite for the osseointegration process in the long bone model.

Healing at implant sites prepared conventionally or by means of Sonosurgery (R): an experimental study in dogs

ObjectiveTo compare peri-implant tissue healing at implants installed in sites prepared with conventional drills or a sonic device.Material and methodsIn six Beagle dogs, the mandibular premolars and first molars were extracted bilaterally. After 3 months, full-thickness muco-periosteal flaps were elevated and recipient sites were prepared in both sides of the mandible. In the right side (control), the osteotomies were prepared using conventional drills, while, at the left side (test), a sonic device (Sonosurgery((R))) was used. Two implants were installed in each side of the mandible. After 8weeks of non-submerged healing, biopsies were harvested and ground sections prepared for histological evaluation.ResultsThe time consumed for the osteotomies at the test was more than double compared to the conventional control sites. No statistically significant differences were found for any of the histological variables evaluated for hard and soft tissue dimensions. Although not statistically significant, slightly higher mineralized bone-to-implant contact was found at the test (65.4%) compared to the control (58.1) sites.ConclusionsSimilar healing characteristics in osseointegration and marginal hard tissue remodeling resulted at implants installed into osteotomies prepared with conventional drills or with the sonic instrument (Sonosurgery((R))).

Healing of implants installed in over- or under-prepared sites: an experimental study in dogs

ObjectiveTo study bone healing at implants installed with different insertion torques.Material and methodsIn six Labrador dogs, all mandibular premolars and first molars were extracted. After 4months of healing, flaps were elevated, and two implant sites were prepared at each side of the mandible. In the right side of the mandible, the distal sites were prepared conventionally, while the mesial sites were over-prepared by 0.2mm. As a consequence, a final insertion torque of similar to 30Ncm at the distal and a minimal insertion torque close to 0Ncm at the mesial sites were obtained. In the left sides of the mandible, however, the recipient sites were underprepared by 0.3mm resulting in an insertion torque of 70Ncm at both implants. Cover screws were applied, and flaps sutured to fully submerge the experimental sites. After 4months, the animals were sacrificed and ground sections obtained for histological evaluation.ResultsThe mineralized bone-to-implant contact was in the range of 55.2-62.1%, displaying the highest value at implants with similar to 30Ncm insertion torque and the lowest value at the implant sites with close to 0Ncm insertion torque. No statistically significant differences were revealed. Bone density was in the range of 43.4-54.9%, yielding the highest value at implants with 70Ncm insertion torque and the lowest at the implant sites with close to 0Ncm insertion torque. The difference between the sites of similar to 30Ncm and the corresponding 70Ncm insertion torque reached statistical significance.ConclusionsSimilar amounts of osseointegration were obtained irrespective of the insertion torque applied. Moreover, implants installed in sites with close to 0Ncm insertion torque may properly osseointegrate as well.