Phytotherapy: an introduction to its history, use and application

There has been a great advance in the pharmacognosy field, which has increased the use of medicinal plants by health professionals and practitioners of folk medicine. This systematic review explored the history and the present day application of phytotherapeutic medicines. We searched the databases Cochrane Library, Embase, Lilacs, PubMed, Scielo and a specialized bibliography. We concluded that there are many therapeutic potentialities in the use of phytotherapeutic medicines and medicinal plants. We also concluded that despite the increasing number of publications in the field each year, there is still a lack of reviews and meta-analyses that could promote a better integration of the knowledge produced. In addition, research about pharmacological interactions and multidisciplinary studies may promote a quicker and safer process from the workbench up to the clinical trials.

Influence of Platform and Abutment Angulation on Peri-Implant Bone. A Three-Dimensional Finite Element Stress Analysis

The aim of this study was to evaluate stress distribution on the pen-implant bone, simulating the influence of Nobel Select implants with straight or angulated abutments on regular and switching platform in the anterior maxilla, by means of 3-dimensional finite element analysis. Four mathematical models of a central incisor supported by external hexagon implant (13 mm x 5 mm) were created varying the platform (R, regular or S. switching) and the abutments (S, straight or A, angulated 15 degrees). The models were created by using Mimics 13 and Solid Works 2010 software programs. The numerical analysis was performed using ANSYS Workbench 10.0. Oblique forces (100 N) were applied to the palatine surface of the central incisor. The bone/implant interface was considered perfectly integrated. Maximum (sigma(max)) and minimum (sigma(min)) principal stress values were obtained. For the cortical bone the highest stress values (sigma(max)) were observed in the RA (regular platform and angulated abutment, 51 MPa), followed by SA (platform switching and angulated abutment, 44.8 MPa), RS (regular platform and straight abutment, 38.6 MPa) and SS (platform switching and straight abutment, 36.5 MPa). For the trabecular bone, the highest stress values (sigma(max)) were observed in the RA (6.55 MPa), followed by RS (5.88 MPa), SA (5.60 MPa), and SS (4.82 MPa). The regular platform generated higher stress in the cervical periimplant region on the cortical and trabecular bone than the platform switching, irrespective of the abutment used (straight or angulated).

Stress distribution on dentin-cement-post interface varying root canal and glass fiber post diameters. A three-dimensional finite element analysis based on micro-C data

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

Análise de falhas por fadiga de alto ciclo em eixos de transmissão utilizando o método dos elementos finitos

This work presents a study that aims to validate the fatigue analyses developed on finite element commercial software, ANSYS Workbench. It was based on mechanical tests development of traction and hardness, to verify the mechanical properties of material that the shaft was manufactured (ABNT 1045 steel), it was developed bend test, with purpose to prove the confiability degree of computational analyses, obtaining the maximum stress in a work condition determined with 40 [kgf] of load applied, and at the end, was developed the fatigue test to obtain the number of cycles that the transmission shaft can support in a work condition with 8 [kgf] of load applied. The results obtained during the work present, have to be quite satisfactory with the theoretically expected

Distribuição de tensões em bocais de vasos de pressão

This work is to analyze the behavior of context concentrated stresses generated around a nozzle connected to a pressure vessel. For this analysis we used the finite element method via a computer interface, the software ANSYS WORKBENCH. It was first necessary to study and intensive training of the software used, and also a study of the ASME Code, Section VIII, which is responsible for the standards used in pressure vessels. We analyzed three cases, which differ primarily in the variation of the diameter of the nozzle in order to analyze the variation of the stresses according to the variation of the diameters. The nozzle diameters were 35, 75 and 105 mm. After the model designed vessel, a pressure was applied on the innervessel of 0.5 MPa. For the smallest diameter, was found the lowest tensions concentrated. Varying between 1 and 223 MPa. Increasing the diameter of the nozzle resulted in increased tensions concentrated around the junction nozzle /vessel. The maximum stresses increased by 78% when the value was increased in diameter from 35 to 75 mm. Since the increase in diameter from 75 to 105 mm, the values of the tensions increased around 43%. These figures emphasize that stress concentrations increased with increasing the diameter of the nozzles, but not linearly

Análise estática de um guindaste de torre, utilizando o método dos elementos finitos

The finite element method is of great importance for the development and analysis of a new product being designed or already on the market, and that requires some specific request or special application. The tower crane, being an essential equipment for modern construction to increase productivity and safety on construction sites, is required for many types of special applications day after day, in many kinds of work. Paying attention to this growing need for handling special projects for the tower crane, faced with the importance and necessity of development and improvement of knowledge in more accurate and practical calculation methods such as the finite element method , for greater agility and precision in the response to a new project. The tower crane is defined by the maximum load moment that it can act with a certain amount of load. The tower crane which will be analyzed in this work , for example, is a tower crane with a resulting capacity of 85 Metric Tons which are considered basic dimensions data of a fisical tower crane of a crane company Liebherr in Guaratinguetá . Thus, the project analysis will begin with the threedimensional representation of the crane lines with AutoCAD software , conversion of this model to the format accepted ANSYS Workbench and completion of 3D modeling of structural components in Design module ANSYS software. After structural modeling is completed, the simulation is performed in static simulation of ANSYS Workbench software mode. The standards will be adopted to DIN (Deutsches Institut für Normung) and EN 14439 (Europäische Normung 14439) and some NR 's related to specific security class of tower cranes, which will be referred throughout the work

Projeto estrutural e parametrização de uma comporta deslizante utilizando o software inventor

Pós-graduação em Engenharia Mecânica - FEG

Stress distribution in delayed replanted teeth splinted with different orthodontic wires: a three-dimensional finite element analysis

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

Influence of occlusal contact area on cusp defection and stress distribution

The purpose of this study was to evaluate the effect of occlusal contact area for loading on the cuspal defection and stress distribution in a first premolar restored with a high elastic modulus restorative material. The Rhinoceros 4.0 software was used for modeling the three-dimensional geometries of dental and periodontal structures and the inlay restoration. Thus, two different models, intact and restored teeth with three occlusal contact areas, 0.1, 0.5 and 0.75 mm(2), on enamel at the occlusal surface of buccal and lingual cusps. Finite element analysis (FEA) was performed with the program ANSYS (Workbench 13.0), which generated a mesh with tetrahedral elements with greater refinement in the regions of interest, and was constrained at the bases of cortical and trabecular bone in all axis and loaded with 100 N normal to each contact area. To analysis of maximum principal stress, the smaller occlusal contact area showed greater compressive stress in region of load application for both the intact and inlay restored tooth. However, tensile stresses at the occlusal isthmus were similar for all three tested occlusal contact areas (60 MPa). To displacement of the cusps was higher for teeth with inlay (0.46-0.48 mm). For intact teeth, the smaller contact area showed greater displacement (0.10 mm). For teeth with inlays, the displacement of the cusps were similar in all types of occlusal area. Cuspal displacement was higher in the restored tooth when compared to the intact tooth, but there were no significant variations even with changes in the occlusal contact area. RELEVANCE CLINICAL: Occlusal contacts have a great influence on the positioning of teeth being able to maintain the position and stability of the mandible. Axial loads would be able to generate more uniform stress at the root presenting a greater concentration of load application in the point and the occlusal surface. Thus, is necessary to analyze the relationship between these occlusal contacts as dental wear and subsequent occlusal interferences.

Zirconia-based dental crown to support a removable partial denture: a three-dimensional finite element analysis using contact elements and micro-CT data

Veneer fracture is the most common complication in zirconia-based restorations. The aim of this study was to evaluate the mechanical behavior of a zirconia-based crown in a lower canine tooth supporting removable partial denture (RPD) prosthesis, varying the bond quality of the veneer/coping interface. Microtomography (μCT) data of an extracted left lower canine were used to build the finite element model (M) varying the core material (gold core - MAu; zirconia core - MZi) and the quality of the veneer/core interface (complete bonded - MZi; incomplete bonded - MZi-NL). The incomplete bonding condition was only applied for zirconia coping by using contact elements (Target/Contact) with 0.3 frictional coefficients. Stress fields were obtained using Ansys Workbench 10.0. The loading condition (L = 1 N) was vertically applied at the base of the RPD prosthesis metallic support towards the dental apex. Maximum principal (σmax) and von Mises equivalent (σvM) stresses were obtained. The σmax (MPa) for the bonded condition was similar between gold and zirconia cores (MAu, 0.42; MZi, 0.40). The incomplete bonded condition (MZi-NL) raised σmax in the veneer up to 800% (3.23 MPa) in contrast to the bonded condition. The peak of σvM increased up to 270% in the MZi-NL. The incomplete bond condition increasing the stress in the veneer/zirconia interface.

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.

Avaliação da distribuição das forças produzidas com arco lingual removível pelo método de elementos finitos

Pós-graduação em Ciências Odontológicas - FOAR

Role of ATM and PTEN in prostatic carcinogenic dog prostate: validation of aCGH results

The canis lupus familiares is the only species besides human that spontaneously develop prostatic carcinoma (PCa). In addition, the metastatic sites are similar to those frequently reported in men. For these reasons, the dog is the best natural model to study the molecular mechanisms in PCa development providing a natural animal model for treatment by molecular targets. Previously, we investigated copy number alterations by arrayCGH (Canine Genome CGH Microarray 4x44K-G2519F, Agilent Technologies) in canine prostatic lesions: 3 benign prostatic hyperplasias (BPH), 4 proliferative inflammatory atrophies (PIA), and 14 PCa. Five histologically normal prostatic tissues were used as reference. Genomic alterations were evaluated using Genomic Workbench Standard Edition 5.0.14. This previous study revealed significant copy number losses of Atm and Pten exclusively in PCa. In the present study, ATM and PTEN immunoexpression were investigated using a tissue microarray (TMA) containing 149 canine prostatic paraffin-embedded lesions (BPH, PIA and PCa) collected from 67 animals. Immunohistochemical reactions were performed using the polyclonal rabbit antibody anti-PTEN (Santa Cruz Biotech, 1:50) and anti-ATM (Abcam, 1:50). The sections were developed with diaminobenzidine (DAB) and peroxidase. The immunohistochemical staining was assessed in each core by the distribution of positive cells for each antibody per lesion (score 1: <25% cells positive, 2: 26% to 50%, 3: being 51% and 75% and 4:> 75%) and intensity (1: weak, 2: moderate, 3: intense). Chi-square or Fisher exact test was used to determine the association between the categorical variables using GraphPad Prism 5 (GraphPad Software Inc., La Jolla, CA). Distribution of positive cells did not differ among lesions. PCa and PIA showed more samples with weak intensity for ATM when compared to normal prostatic tissue and BPH (PCa: p=0,032 and PIA: p=0,025). Benign prostatic hyperplasia and normal samples presented intense PTEN immunostaining than PCa (p=0,021) and PIA (p=0,0013). These results suggest that ATM and PTEN proteins expression in canine prostatic carcinoma are downregulated possibly by copy number losses. These findings are similar from those described in prostate carcinomas from human corroborating for the use of dogs as a natural model to study prostatic disease in men.

Genomic gains in prostatic carcinoma and proliferative inflammatory atrophy in dogs

The dog can spontaneously develop prostate cancer and consequently can be used as an experimental model for prostatic diseases associated with aging, including benign prostate hyperplasia (BPH) and prostate carcinoma (PCa). DNA copy number variations (CNVs) have been used to identify genes associated with cancer development and progression. DNA microarray based comparative genomic hybridization (aCGH) is a technique that allows to identify copy number of thousands of genes throughout the genome. aCGH was used to identify genomic regions with significantly different DNA copy number in three benign prostatic hyperplasia (BPH), four proliferative inflammatory atrophy (PIA), and 14 canine prostate carcinoma (PCa). Five histologically normal prostate tissue were used as reference. Genomic DNA was extracted from formalin fixed and paraffin embedded samples and CNVs data was evaluated in Canine Genome CGH Microarray 4x44K (G2519F, Design ID021193, Agilent). Data analysis was performed using Genomic Workbench Standard Edition 5.0.14 (Agilent). PCa showed higher number of altered genes related to canonical diseases process, cellular functions and molecular pathways as well as greater inter-relationship between genes, compared with PIA and BPH. In conclusion, PCa showed a more complex genotype, being losses the most frequent genomic changes. Some discrepancies between genomic alterations in human and canine carcinomas may indicate the different clinical behavior of these tumors in these two species. In addition, it was observed was an ascending pattern of genomic complexity in BPH, PIA and CA consistent with a model of multistep tumor progression.