Clopidogrel Enhances Periodontal Repair in Rats Through Decreased Inflammation

Aim We hypothesized that platelet inactivation induced by drugs might interfere with periodontal repair in experimental periodontitis by suppressing the release of biological mediators from platelets at the site of injury. Material and Methods 60 rats were randomly assigned to 6 groups (n=10) and ligatures were placed around lower first molars of three groups. The other three groups were used as negative controls. Ligatures were removed after 10 days of periodontitis induction and all groups were submitted to treatment with aspirin (Asp) (30 mg/kg), clopidogrel (Clop) (75 mg/kg) or NaCl 0.9% intragastrically once daily for 3 days. Periodontal tissue was assessed by the measurement of CXCL12, CXCL4, CCL5 and PDGF by ELISA; histomorphometric analysis of PMN infiltration, attachment loss, bone loss and osteoclast numbers and quantification of blood vessels by imunnohistochemistry. Results During periodontal repair and treatment with NaCl 0.9%, CCL5 was decreased and CXCL12 increased when compared to negative control groups. Asp and Clop did not affect CCL5 expression, decreased CXCL12 but only Clop decreased CXCL4 and PDGF content compared to saline-treated animals. Clop increased blood vessel number, reduced PMN count, and decreased attachment and bone loss, also decreased osteoclast number in animals submitted or not to periodontal repair. Conclusion Systemic administration of Clop during 3 days improved the repair process associated with experimental periodontal disease, suggesting that it may have therapeutic value under situations where tissues undergo a transition from inflammation to repair

Diabetes Reduces Mesenchymal Stem Cells in Fracture Healing Through a TNFα-Mediated Mechanism

Aims/hypothesis Diabetes interferes with bone formation and impairs fracture healing, an important complication in humans and animal models. The aim of this study was to examine the impact of diabetes on mesenchymal stem cells (MSCs) during fracture repair. Methods Fracture of the long bones was induced in a streptozotocin-induced type 1 diabetic mouse model with or without insulin or a specific TNFα inhibitor, pegsunercept. MSCs were detected with cluster designation-271 (also known as p75 neurotrophin receptor) or stem cell antigen-1 (Sca-1) antibodies in areas of new endochondral bone formation in the calluses. MSC apoptosis was measured by TUNEL assay and proliferation was measured by Ki67 antibody. In vitro apoptosis and proliferation were examined in C3H10T1/2 and human-bone-marrow-derived MSCs following transfection with FOXO1 small interfering (si)RNA. Results Diabetes significantly increased TNFα levels and reduced MSC numbers in new bone area. MSC numbers were restored to normal levels with insulin or pegsunercept treatment. Inhibition of TNFα significantly reduced MSC loss by increasing MSC proliferation and decreasing MSC apoptosis in diabetic animals, but had no effect on MSCs in normoglycaemic animals. In vitro experiments established that TNFα alone was sufficient to induce apoptosis and inhibit proliferation of MSCs. Furthermore, silencing forkhead box protein O1 (FOXO1) prevented TNFα-induced MSC apoptosis and reduced proliferation by regulating apoptotic and cell cycle genes. Conclusions/interpretation Diabetes-enhanced TNFα significantly reduced MSC numbers in new bone areas during fracture healing. Mechanistically, diabetes-enhanced TNFα reduced MSC proliferation and increased MSC apoptosis. Reducing the activity of TNFα in vivo may help to preserve endogenous MSCs and maximise regenerative potential in diabetic patients

Proposta de acompanhamento tutorial : um projecto de acção em contexto escolar

No presente estudo, analisam-se os principais problemas diagnosticados num Agrupamento de Escolas, identificando as principais necessidades, fragilidades, assim como os recursos vigentes no mesmo. Nesse sequência é apresentada uma Proposta de Acompanhamento Tutorial de forma a dotar o Agrupamento de meios que possam servir as exigências, colocadas no âmbito do domínio da acção socioeducativa. A proposta de acompanhamento tutorial que se apresenta, assenta neste propósito, enquadrando e reflectindo o papel fundamental de uma equipa multidisciplinar permanente, constituída pelos seguintes técnicos: Psicólogo, Professor Tutor e Director de Turma, que em conjunto elaboram um Plano Individual de Acompanhamento Tutorial (PIAT). No PIAT são mencionadas as áreas onde o aluno requer um acompanhamento técnico e definidas as estratégias a serem desenvolvidas por cada ano lectivo, durante todo o seu percurso escolar. Após a definição dos possíveis técnicos a intervir e recursos necessários, para a sua implementação, é definida nomeadamente a duração da mesma e a articulação com a família e redes sociais envolventes.In this study, we analyze the main problems diagnosed in a Group of Schools, identifying key needs, weaknesses, and resources existing in it. Following this is a Proposal Monitoring Tutorial in order to provide the grouping of resources which can serve the demands placed within the field of socio-educational action. The proposed follow tutorial that shows, based on this point, framing and reflecting the fundamental role of a permanent multi-disciplinary team, consisting of the following technicians: Psychologist, Teacher and Director of Tutor Team, which together draw up an Individual Plan Monitoring Tutorial (PIAT). PIAT are mentioned in the areas where the student requires a technical monitoring and defined strategies to be developed for each academic year throughout their school careers. After defining the technical potential to intervene and resources necessary for its implementation, is defined including its duration and interaction with the surrounding family and social networks

The Effect of Supra- and Subphysiologic Testosterone Levels on Ligature-Induced Bone Loss in Rats - A Radiographic and Histologic Pilot Study

Background: Testosterone is the primary male sexual hormone, and varying concentrations of the hormone mediated by physiologic, pathologic, or pharmacologic mechanisms may induce large variations in the body. Data regarding the general role of testosterone in mediating inflammation are still inconclusive. Therefore, the purpose of this study is to assess the consequences of supra- and subphysiologic levels of testosterone on ligature-induced bone loss in rats.Methods: Three male adult Holtzman rats were used to observe the course of serum testosterone concentration following orchiectomy (Ocx) and testosterone injections. Another 60 rats were randomly assigned to the following groups: 1) sham-operation controls (n = 10); 2) sham-operation and ligature-induced bone loss (n = 10); 3) orchiectomy without ligature (Ocx; n = 10); 4) Ocx and ligature (n = 10); 5) Ocx plus 250 mg/kg body weight intramuscular testosterone esters injection without ligature (Ocx+T; n = 10); and 6) Ocx, T, and ligature (n = 10). The ligatures were placed 30 days post-orchiectomy (or sham-operation) and maintained for 15 days. Thereafter, the rats were sacrificed, and their hemimandibles were used for radiographic evaluation of bone loss along with histologic and histometric analyses of gingival tissue.Results: The results indicated a significant increase in bone loss in the Ocx and Ocx+T groups in the presence and absence of inflammation, respectively. In addition, the Ocx and Ocx+T groups presented increased gingival area accompanying ligature-induced bone loss.Conclusions: Both sub- and supraphysiologic testosterone levels may influence bone metabolism, but only subphysiologic levels significantly increase ligature-induced bone loss. Moreover, testosterone has a regulatory effect on the gingival area. J Periodontol 2012;83:1432-1439.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Platelet-rich plasma stimulates cytokine expression and alkaline phosphatase activity in osteoblast-derived osteosarcoma cells

Objective: The aim of this study was to investigate the effects of PRP on SAOS-2 cells in terms of cytokine expression, cell activity and oxidative stress. Design: Cell line SAOS-2 (1 x 10(5) cells/mL) were grown in culture medium alpha-MEM with 10% FBS for 24 h and stimulated (or not) with PRP at concentrations of 3, 10 and 20%, LPS (E. coli, 10 g/mL) and IL-1 beta (1 mg/mL) for 24 h. The supernatant was collected and analyzed for the expression of cytokines in a panel array, ALP using a commercial kit and NO2- with Griess reaction method. Also, the cells were analyzed using Western blot for RANKL and slot blotting for nitrotyrosine expression. Result: There were no significant differences amongst the groups in terms of NO2-, protein nitrotyrosine content and RANKL expression. However, all stimuli increased ALP activity and in case of PRP, it was in a dose-dependent manner (p < 0.001). Also, all stimuli induced an increase in cytokines and chemokines expression, but only PRP promoted an increase of component C5, sICAM-1 and RANTES expression. Whilst IL-1 receptor antagonist (IL-1ra) expression was down-regulated by PRP, both LPS and IL-1 beta caused up-regulation of this cytokine. Conclusions: PRP can stimulate osteoblast activity and cytokine/chemokine release, as well as indicate some of the mediators that can (and cannot) be involved in this activation. (C) 2012 Elsevier Ltd. All rights reserved.Sao Paulo Research Foundation (FAPESP, Sao Paulo, SP, Brazil) [08/02893-4, 09/1515-0]Sao Paulo Research Foundation (FAPESP, Sao Paulo, SP, Brazil)National Council for Scientific and Technological Development (CNPq, Brasilia, DF, Brazil)National Council for Scientific and Technological Development (CNPq), Brasilia, DF, Brazi

Microbial invasion: focal infection and relationship with atherosclerosis

Os extraordinários avanços no desempenho de técnicas laboratoriais corroboram na evolução do entendimento dos mecanismos das doen- ças de modo geral, facilitando o tratamento e/ou a prevenção. De fato, informações equilibradas, acuradas e atuais estão colaborando de forma estimulante no estudo da relação entre doença periodontal e periapical crônica com o desenvolvimento ou estabelecimento de algumas doen- ças cardiovasculares. Dessa forma, o objetivo da presente trabalho foi descrever de forma sucinta e objetiva a relação entre doença periodontal crônica e doença periapical como fatores de risco para o desenvolvimento ou estabeleciomento da aterosclerose. Estudos epidemiológicos têm procurado demonstrar que indivíduos com doença periodontal ou periapical poderiam apresentar um aumento significativo do risco de desenvolver algumas doenças sistêmicas incluindo a aterosclerose

Curcumin modulates the immune response associated with LPS-induced periodontal disease in rats

Curcumin is a plant-derived dietary spice ascribed various biological activities. Curcumin therapeutic applications have been studied in a variety of conditions, but not on periodontal disease. Periodontal disease is a chronic inflammatory condition initiated by an immune response to micro-organisms of the dental biofilm. Experimental periodontal disease was induced in rats by injecting LPS in the gingival tissues on the palatal aspect of upper first molars (30 mu g LPS, 3 times/week for 2 weeks). Curcumin was administered to rats daily via oral gavage at 30 and 100 mg/kg body weight. Reverse transcriptase-qPCR and ELISA were used to determine the expression of IL-6, TNF-alpha and prostaglandin E-2 synthase on the gingival tissues. The inflammatory status was evaluated by stereometric and descriptive analysis on hematoxylin/eosin-stained sections, whereas modulation of p38 MAPK and NK-kappa B signaling was assessed by Western blot. Curcumin effectively inhibited cytokine gene expression at mRNA and protein levels, but NF-kappa B was inhibited only with the lower dose of curcumin, whereas p38 MAPK activation was not affected. Curcumin produced a significant reduction on the inflammatory infiltrate and increased collagen content and fibroblastic cell numbers. Curcumin potently inhibits innate immune responses associated with periodontal disease, suggesting a therapeutic potential in this chronic inflammatory condition.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES