Avaliação da resposta tecidual e capacidade de mineralização de cimentos que contém compostos biocerâmicos, resinosos e com hidróxido de cálcio

Pós-graduação em Ciência Odontólogica - FOA

The effects of environmental enrichment on biochemical and metric parameters of aged rats

The enriched environment (EE) is a promoter of physical activity, by its characteristics such as ample room for movement and exploration, presence of wheels, tunnels and toys. The maintenance of animals in enriched environment can bring a range of benefits, but the majority of the researches investigate cognitive parameters and changes related to the nervous system. The aim of this study was to examine the effects of the maintenance of aged rats in enriched cages on biochemical and metric parameters. Wistar rats were randomly distributed (n=6) into two groups during 6 weeks: control (C) in a conventional cage and enriched environment (EE). The body mass were recorded weekly and the body length at the end of the study. After euthanasia, blood was collected for analysis of glucose, triglycerides and the brain was collected for analysis of mass. The EE group had higher brain mass and lower gain of body weight compared to control group. The control group animals had normal values of blood glucose and triglyceride levels, and the maintenance in an EE did not promote changes in these parameters. Therefore, it can be concluded that the EE group increases brain mass and reduces the gain of body weight without changing the blood glucose and triglycerides in aged animals.

Effect of mesenchymal stem cells on movement and urination of rats with spinal cord injury

Cell therapy has frequently been reported as a possible treatment for spinal trauma in humans and animals; however, without pharmacologically curative action on damage from the primary lesion. In this study, we evaluated the effect of administering human adipose-derived stem cells (hADSC) in rats after spinal cord injury. The hADSC were used between the third and fifth passages and a proportion of cells were transduced for screening in vivo after transplantation. Spinal cord injury was induced with a Fogarty catheter no. 3 inserted into the epidural space with a cuff located at T8 and filled with 80 mu L saline for 5 min. The control group A (n = 12) received culture medium (50 mu L) and group B (n = 12) received hADSC (1.2 x 10(6)) at 7 and 14 days post-injury, in the tail vein. Emptying of the bladder by massage was performed daily for 3 months. Evaluation of functional motor activity was performed daily until 3 months post-injury using the Basso-Beattie-Bresnahan scale. Subsequently, the animals were euthanized and histological analysis of the urinary bladder and spinal cord was performed. Bioluminescence analysis revealed hADSC at the application site and lungs. There was improvement of urinary bladder function in 83.3% animals in group B and 16.66% animals in group A. The analysis of functional motor activity and histology of the spinal cord and urinary bladder demonstrated no significant difference between groups A and B. The results indicate that transplanted hADSC improved urinary function via a telecrine mechanism, namely action at a distance.

Diuretic and hipotensive activity of aqueous extract of parsley seeds (Petroselinum sativum Hoffm.) in rats

A espécie vegetal, Petroselinum sativum Hoff, conhecida como salsa, é amplamente utilizada na medicina popular brasileira como diurético. O objetivo desse estudo é verificar se o uso brasileiro do extrato aquoso da salsa tem efeitos semelhantes com investigações que mostram o efeito diurético da P. sativum em ratos. MÉTODOS: 19 Ratos foram anestesiados e canulamos a traquéia, artéria carótida esquerda (para a medição da pressão arterial) e bexiga urinária (para coletar urina). Depois de 40 minutos para adaptação das condições cirúrgicas, ratos anestesiados foram administrados de acordo com seus grupos: controle (CON), administração oral com 1.0 mL de água filtrada, e grupo tratado (AE), administração oral com extrato aquoso de sementes de salsa 20% (AE). Urina foi coletada três vezes (de 30 em 30 minutos) e então esse material foi utilizado para determinações de sódio e potássio, para avaliar a quantidade excretada desses íons. Pressão arterial foi medida pelo manômetro de mercúrio por 9 vezes. Todos os dados foram estatisticamente avaliados. RESULTADOS E CONCLUSÃO: nos parâmetros anestesiados, o grupo CON não mostrou nenhuma diferença; mas o grupo AE mostrou um aumento do fluxo urinário e da quantidade excretada de sódio e potássio, e também uma diminuição da pressão arterial. Todos os parâmetros apresentaram essas modificações após 30 minutos de administração do AE (p<0,05). Esses resultados mostram que o tratamento com o AE leva a efeitos natriurético e hipotensor em ratos Wistar anestesiados, confirmando o uso da população brasileira dessa erva como diurético.

Influência do extrato de chá verde na remodelação cardíaca induzida por administração de doxorrubicina

Pós-graduação em Fisiopatologia em Clínica Médica - FMB

Efeitos da administração em longo prazo do omeprazol sobre a densidade mineral óssea e as propriedades mecânicas do osso

Objectives: Epidemiological studies have shown a relationship between long-term use of proton pump inhibitors and bone metabolism. However, this relationship has not yet become established. The aim of the present study was to analyze the mechanical properties and bone mineral density (BMD) of rats that were subjected to long-term omeprazole use. Methods: Fifty wistar rats weighing between 200 and 240 g were divided equally into five groups: OMP300 (omeprazole intake at a dose of 300 moL/kg/day); OMP200 (200 moL/ kg/day); OMP40 (40 moL/kg/day); OMP10 (10 moL/kg/day); and Cont (control group; intake of dilution vehicle). The solutions were administered for 90 consecutive days. After the rats had been sacrificed, their BMD, the mechanical properties of the dissected femurs and their serum Ca++ levels were analyzed. Results: The BMD of the OMP300 group was lower than that of the controls (p = 0.006). There was no difference in comparing the OMP200, OMP40 and OMP10 groups with the controls. The maximum strength and rigidity of the femur did not differ in the experimental groups in comparison with the controls. The OMP300 group had a statistically lower serum Ca++ concentration than that of the controls (p = 0.049), but the other groups did not show any difference in relation to the controls. Conclusion: Daily intake of 300moL/kg/day of omeprazole decreased the BMD of the femur, but without changes to the rigidity and strength of the femur in adult rats. © 2

Erva mate minimiza as alterações do perfil lipídico promovidas por elevado consumo de sacarose

The yerba mate (Ilex paraguariensis) is composed of bioactive that interfere with lipid metabolism. The objective was to evaluate if daily consumption of mate tea (MT) change the lipid deposits and dyslipidemia caused by excessive consumption of sucrose. Thirty male Wistar rats (40 days old) were divided into four groups: Group C - free access to commercial chow and deionized water; S - free access to commercial food, water and sucrose solution 30% (w/v) in water; MTS and deionized - free access to commercial feed solution, water, 30% sucrose (w/v) and treated with daily infusion of MT (soluble mate Leão Júnior®) via orogastric tube at a dose of 100 mg/kg/mc for 8 weeks. After the trial period the lipid profile was evaluated by the following parameters: a) direct weighing of the retroperitoneal (RP) and epididymal (EPI) adipose tissues; b) determination of plasma total cholesterol, triglycerides and HDL cholesterol concentration. The MT promoted the reduction of 1.4 times in both tissues RP and EPI in MTS group compared to group S. Treatment with MT decreased 2.7 times triglyceride in the MTS group compared with the group S. The sucrose consumption did not alter the plasma cholesterol concentration, however the consumption of MT significantly reduced total cholesterol circulating. The HDL cholesterol concentration, in the MTS group, showed higher concentration than in group S (1.3 times). MT prevents in young male rats the increase of lipid deposits and dyslipidemia caused by excessive consumption of sucrose.

Delayed tooth replantation after treatment of necrotic periodontal ligament with citric acid

Objective: to evaluated the effect of treating root-adhered necrotic periodontal ligament (PDL) with citric acid on the healing process in delayed rat tooth replantation. Material and Methods: Forty Wistar rats, assigned to 4 groups (n=10), had their upper right incisor extracted and kept dry on a workbench. For Group I (control), the teeth were replanted after a 5 min extra-alveolar time. For the other groups, replantation was hydroxide-based paste and the teeth were replanted with no root surface treatment. In Group III, the teeth were immersed in citric acid (pH 1) for replanted. In Group IV, instead of the immersion, the roots were scrubbed with gauze soaked in citric acid and the teeth were replanted. The animals difference (p > 0.05) was found among the groups regarding the areas difference (p < 0.05) between the control group and Group IV regarding ankylosis. The control group showed the least replacement resorption percent means compared to the other groups (p < 0.05). The root structure was more affected by replacement resorption and ankylosis in Group IV statistically (p > 0.05). Conclusion: the treatment of root surface-adhered necrotic periodontal ligament with citric acid was not able to prevent the delayed rat tooth replantation.

Delayed tooth repalantetion after treatment of necrotic periodontal ligament with citric acid

Objective: to evaluated the effect of treating root-adhered necrotic periodontal ligament (PDL) with citric acid on the healing process in delayed rat tooth replantation. Material and Methods: Forty Wistar rats, assigned to 4 groups (n=10), had their upper right incisor extracted and kept dry on a workbench. For Group I (control), the teeth were replanted after a 5 min extra-alveolar time. For the other groups, replantation was done after 60 min. In Group II, the root canals were filled with a calcium hydroxide-based paste and the teeth were replanted with no root surface treatment. In Group III, the teeth were immersed in citric acid (pH 1) for 3 min, the canals were filled with calcium hydroxide and the teeth were replanted. In Group IV, instead of the immersion, the roots were scrubbed with gauze soaked in citric acid and the teeth were replanted. The animals were sacrificed 60 days postoperatively. Results: Regarding replacement resorption, there was statistically significant difference (p < 0.05) between the control group and the other three groups. No statistically significant difference (p > 0.05) was found among the groups regarding the areas of inflammatory resorption. There was also a statistically significant difference (p < 0.05) between the control group and Group IV regarding ankylosis. The control group showed the least replacement resorption percent means compared to the other groups (p < 0.05). The root structure was more affected by replacement resorption and ankylosis in Group IV compared to the Groups II and III, but this difference was not significant statistically (p > 0.05). Conclusion: the treatment of root surface-adhered necrotic periodontal ligament with citric acid was not able to prevent the occurrence of ankylosis, root resorption and inflammatory resorption in delayed rat tooth replantation.

O efeito do consumo abusivo de alvool no torque de remoção de implantes de titânio

Studies have reported that alcohol may lead to imbalance in bone formation and resorption, however, its effects on osseointegration of titanium implants continues to be an inconclusive subject. In this context, the aim of this study was to make a biomechanical evaluation of the effect of abusive alcohol consumption on the removal torque of osseointegrated titanium implants. Male Wistar rats (n=30) were divided into two experimental groups (15 each) receiving only water (Control) or 36% alcohol solution oral administration. Thirty days later, all animals were submitted to titanium implant (2.2 mm x 4 mm) placement in the right and left tibiae. The surgical alveoli were prepared with a 2 mm drill mounted in a counter-angle hand-piece (20:1 ratio, 35 Ncm torque at 1200 rpm) under abundant cooling. Five animals from each group were euthanized at 15, 30, and 60 days. Tibiae were submitted to reverse torque analysis. Data obtained were submitted to statistical analysis by the non-parametric Kruskal-Wallis and Dunn Tests (p < 0.05). Animals in the alcohol group presented lower removal torque values when compared with control group animals for all periods tested (p < 0.05). It can be concluded that abusive alcohol consumption can reduce the removal torque of titanium implants placed in rat tibiae, suggesting that alcohol may interfere in the osseointegration process of titanium implants.

O efeito do consumo abusivo de álcool no torque de remoção de implante de titânio

Studies have reported that alcohol may lead to imbalance in bone formation and resorption, however, its effects on osseointegration of titanium implants continues to be an inconclusive subject. In this context, the aim of this study was to make a biomechanical evaluation of the effect of abusive alcohol consumption on the removal torque of osseointegrated titanium implants. Male Wistar rats (n=30) were divided into two experimental groups (15 each) receiving only water (Control) or 36% alcohol solution oral administration. Thirty days later, all animals were submitted to titanium implant (2.2 mm x 4 mm) placement in the right and left tibiae. The surgical alveoli were prepared with a 2 mm drill mounted in a counter-angle hand-piece (20:1 ratio, 35 Ncm torque at 1200 rpm) under abundant cooling. Five animals from each group were euthanized at 15, 30, and 60 days. Tibiae were submitted to reverse torque analysis. Data obtained were submitted to statistical analysis by the non-parametric Kruskal-Wallis and Dunn Tests (p < 0.05). Animals in the alcohol group presented lower removal torque values when compared with control group animals for all periods tested (p < 0.05). It can be concluded that abusive alcohol consumption can reduce the removal torque of titanium implants placed in rat tibiae, suggesting that alcohol may interfere in the osseointegration process of titanium implants.

Reação de tecido subcutâneo ao cimento Portland modificado (CPM)

Introdução: o objetivo do estudo foi avaliar a resposta do tecido subcutâneo de ratos a implantes de tubos de polietileno com cimento Portland modificado (CPM) (EGEO S.R.L., Buenos Aires, Argentina) comparado com o MTA Angelus® (Angelus, Londrina/PR). Métodos: esses materiais foram colocados em tubos de polietileno e implantados no tecido conjuntivo dorsal de ratos Wistar por 7, 15, 30, 60 e 90 dias. Os espécimes foram preparados e corados com hematoxilina e eosina ou Von Kossa, ou não corados por luz polarizada. Foram realizadas avaliações quantitativas e qualitativas das reações. Resultados: ambos os materiais causaram reações moderadas em 7 dias, decaindo com o tempo. O MTA Angelus causou reações leves em 15 dias, decaindo com o tempo. A resposta foi similar ao controle em 30, 60 e 90 dias com CPM e MTA Angelus. Foram observadas mineralização e granulações birrefringentes à luz polarizada em ambos os materiais. Conclusões: foi possível concluir que o CPM e o MTA Angelus foram biocompatíveis em modelo de rato e estimularam a mineralização.

Efeito da inibição dos receptores canabinóides CB₁ ou CB₂ durante o período neonatal sobre o dimorfismo sexual esquelético ao longo do desenvolvimento

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo comparativo do Biogran® e Endobon® associados a implantes com defeitos periimplantares

Pós-graduação em Odontologia - FOA

Estudo comparativo do desempenho de diferentes membranas oclusivas de Látex Natural no reparo ósseo

Introduction: In dentistry, alveolar bone resorption is a limiting factor in the well being of individuals directly interfering in the stomatognathic system, causing problems in the context of overall health. Aiming to promote biological methods that can stimulate bone regeneration, several biomimetic strategies have been developed by the use of diverse materials possible to the bone matrix, culminating in the development of techniques that promote such repair. Objective: This work is a comparative study of the performance of films made with latex as occlusive membrane for Guided Bone Regeneration (GBR) procedure in three preparations: Latex preserved in ammonia, produced by Latex rubber clones IAN873 and PR255 polymerized immediately after collection and without use ammonia as a preservative. Methods: Sixty Wistar rats were randomly divided into 4 groups of 15 animals in which bone defects of critical size (8mm diameter) were made surgically in the skull. Group A was treated by GBR through the membrane latex preserved with ammonia, Group B received the membrane made of latex from IAN873, Group C, the membrane clone PR255 and group D was not treated by GBR. After a period of 7, 15 and 50 days, 5 animals from each group were euthanized, and specimens containing bone defect collected for microscopic examination (descriptive histology and histomorphometry). Results: The results showed that after 50 days there was bone formation in higher proportions in group D (p <0.05, ANOVA followed by Tukey), suggesting that further experiments should be conducted to conclude about the presence of ammonia and the influence of kind of rubber. Conclusion: GOR is a procedure proven effective in the treatment of bone defects. Therefore, further experiments should be conducted to reach a conclusion regarding the presence of ammonia in the latex composition for the manufacture of membranes, as well as the difference induced by the species of rubber.