Behaviour of oligodendrocytes and Schwann cells in an experimental model of toxic demyelination of the central nervous system

Oligodendrocytes and Schwann cells are engaged in myelin production, maintenance and repairing respectively in the central nervous system (CNS) and the peripheral nervous system (PNS). Whereas oligodendrocytes act only within the CNS, Schwann cells are able to invade the CNS in order to make new myelin sheaths around demyelinated axons. Both cells have some limitations in their activities, i.e. oligodendrocytes are post-mitotic cells and Schwann cells only get into the CNS in the absence of astrocytes. Ethidium bromide (EB) is a gliotoxic chemical that when injected locally within the CNS, induce demyelination. In the EB model of demyelination, glial cells are destroyed early after intoxication and Schwann cells are free to approach the naked central axons. In normal Wistar rats, regeneration of lost myelin sheaths can be achieved as early as thirteen days after intoxication; in Wistar rats immunosuppressed with cyclophosphamide the process is delayed and in rats administered cyclosporine it may be accelerated. Aiming the enlightening of those complex processes, all events concerning the myelinating cells in an experimental model are herein presented and discussed.

Diretrizes curriculares nacionais para o ensino médio: avaliação de documento

This text offers some contributions to the debate on the changes proposed to the National Curricular Directives to reform secondary education in Brazil. In the first part, the political and economic scene is evaluated as the context which generated the last stage of reforms in the educational field in the 90s. It questions the option for a model of structural reform (in the Brazilian case more restricted to the Program for Reform of Professional Education - PROEP) and of the curriculum, whose themes find their justification in the contemporary economic, social cultural and political context. It discusses the use of a model that bases itself on experiences developed in other countries and takes the international orientation of the multilateral organizations as its theoretical methodological reference, leaving out the peculiarities and injunctions of the Brazilian political administrative system. Such a policy measure can increase the tension and distance normally existing between government programs and the possibility of their real implementation in the school network. In the second part, it discusses the Resolution of the National Education Council, the Congress on Basic Education, no.3, of 16.698 that instituted the National Curricular Directives for secondary education, as well as the Legal Bases - Part I - of the National Curricular Parameters for secondary education. The analysis of official discourse takes Bardin's (1977, p. 209) proposals as its methodological reference for the models of structural analysis, seeking to make the implicit values and the connotations of the legal texts explicit

Identificação eletrônica para avaliação do comportamento dos suínos na fase de gestação

The efficiency of swine production performance depends on the herd administration, such as good nutrition, sanitary control, facilities and appropriate environmental conditions. The concept of this production model is directly related with the reduction of selective losses and the process control. Each production segment is controlled to reach the optimization in the system totality, it is necessary to apply animals handling concepts, environmental control implementation, diseases control, nutrition control, information concerning in guaranteeing the animal welfare and individual identification. The present work presents as objective the development of the mathematical model to evaluate interactions among the internal atmosphere of the installation and the thermal animals preference, in the expectation of detecting a relationship among the frequency access to the drinking fountain and the atmosphere conditions - temperature, black globe temperature and relative humidity, using as tool the electronic identification. The results obtained by the mathematical model, allowed to conclude accurately the evaluation of the swine thermal preference correlating with the climatic variables in the pregnancy stage.

Creatina quinase e dor muscular tardia na musculação : estudo experimental em adultos e jovens com o "circuit weight training" e o "multiple set system"

Universidade Estadual de Campinas . Faculdade de Educação Física

Ta ligado mano : o hip-hop como lazer e resgate da cidadania

Universidade Estadual de Campinas . Faculdade de Educação Física

Formação continuada de professores de educação fisica em ambiente escolar inclusivo

Universidade Estadual de Campinas. Faculdade de Educação Física

Modelo de inclusão digital para construção do conhecimento em qualidade de vida e atividade fisica

Universidade Estadual de Campinas. Faculdade de Educação Física

Concepção e implementação de um sistema para analise cinematica de movimentos humanos

Universidade Estadual de Campinas. Faculdade de Educação Física

Treinamento fisico militar e aptidão fisica relacionada a saude : estudo a partir de conscritos do Tiro-de-Guerra 02-40 Sorocaba, S.P

Universidade Estadual de Campinas. Faculdade de Educação Física

A contribuição da Educação Fisica no processo de humanização do adolescente

Universidade Estadual de Campinas. Faculdade de Educação Física

Microbial distribution in the root canal system after periapical lesion induction using different methods

The aim of this study was to evaluate the microbial distribution in the root canal system after periapical lesion induction in dogs' teeth using different methods. Fifty-two root canals were assigned to 4 groups (n=13). Groups I and II: root canals were exposed to the oral cavity for 180 days; groups III and IV: root canals were exposed for 7 days and then the coronal openings were sealed for 53 days. The root apices of groups I and III were perforated, while those of groups II and IV remained intact. After the experimental periods, the animals were euthanized and the anatomic pieces containing the roots were processed and stained with the Brown & Brenn method to assess the presence and distribution of microorganisms. The incidence of microorganisms at different sites of the roots and periapical lesions was analyzed statistically by the chi-square test at 5% significance level. All groups presented microorganisms in the entire root canal system. A larger number of microorganisms was observed on the root canal walls, apical delta and dentinal tubules (p<0.05), followed by cementum and cemental resorption areas. In spite of the different periods of exposure to the oral environment, the methods used for induction of periapical periodontitis yielded similar distribution of microorganisms in the root canal system.

Influence of sodium hypochlorite and edta on the microtensile bond strength of a self-etching adhesive system

Chemical substances used during biomechanical preparation of root canals can alter the composition of dentin surface and affect the interaction with restorative materials. OBJECTIVE: The purpose of this study was to evaluate the microtensile bond strength (µTBS) of a self-etching adhesive system to dentin irrigated with sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA). MATERIAL AND METHODS: Thirty human third molars were sectioned 3 mm below the occlusal surface, polished with 600- to 1200-grit silicon carbide papers, and randomly divided into 3 groups: G1 (control): no irrigating solution; G2: 1% NaOCl; and G3: 1% NaOCl followed by the application of 17% EDTA. The specimens received the self-etching adhesive system (XENO III - Dentsply), restored with microhybrid composite resin (Z250 - 3M ESPE), sectioned and trimmed to create 4 hourglass-shaped slabs of each tooth. The slabs were tested in microtensile strength in a universal testing machine (Emic DL 2000) at a crosshead speed of 0.5 mm/min until fracture. The results were analyzed statistically by ANOVA and Newman-Keuls test. RESULTS: Mean µTBS values and standard deviations in MPa were: G1 = 11.89 ± 4.22; G2 = 19.41 ± 5.32; G3 = 11.34 ± 4.73. 1% NaOCl increased the adhesive resistance significantly (p<0.001/F=22.5763). The application of 1% NaOCl/17% EDTA resulted in statistically similar µTBS to the control group. CONCLUSIONS: None of the irrigants affected negatively the µTBS of XENO III to dentin. The use of 1% NaOCl alone resulted in higher bond strength than the other treatments. The combination of 1% NaOCl and 17% EDTA produced similar bond strength to that of untreated dentin.

Prevalence of malocclusions in the 13-20-year-old categories of football athletes

The dentist can offer athletes improvement in their physical performance through the maintenance of oral health, preventing and treating any and all changes in the stomatognathic system, such as dental malocclusions, that compromise the athletes' performance. The objective of this study is to research the presence of dental malocclusions in athletes of the category between 13 and 20 years of age, from the São Paulo Football Club. 84 athletes participated in this study, dealing with the following topics: molar relation (Angle's classification); presence of overbite; underbite; overcrowding; abnormal spacing; open bite; and anterior, posterior, bilateral and unilateral crossbite; midline deviation and facial type (mesofacial, brachyfacial and dolichofacial). Only one table was made, showing percentages. In regard to Angle's molar relation, 89% are in Class I, 8% in Class II, 3% Class III, 9% of the athletes had overbite, 4% had underbite, 13% had overcrowding and 21% had abnormal spacing. In regard to the bite, 11% presented anterior open bite. In regard to crossbite, 7% presented unilateral crossbite on the right side and 2% on the left side; 5% presented posterior crossbite and 4% anterior crossbite. In regard to midline deviations, 4% presented deviation in the maxilla and 33% in the mandible. In regard to facial type: 39% are dolichofacial, 4% brachyfacial and 57% mesofacial. Based on the results shown, proposals for the implementation of dental, phoniatric, and Ear, Nose and Throat (ENT) practices are already being discussed with the multidisciplinary team of the club involved.

Do the origins of primary teeth affect the bond strength of a self-etching adhesive system to dentin?

The aim of this in vitro study was to evaluate the tensile bond strength of a self-etching adhesive system to three different dentinal substrates. Primary molar teeth that had been recently exfoliated (RE), with unknown time of exfoliation (UT), and extracted due to prolonged retention (PR) were used for this investigation. Ten primary molar teeth of each group were cut in the middle following the mesio-distal direction, creating a total of twenty specimens per group. The specimens were included in acrylic resin and had a flat dentin surface exposed. The self-etching adhesive system was applied to this surface and a 3-millimeter high cone with diameter of 2 mm in the adhesion area was constructed using composite resin. The specimens were stored in distilled water at 37ºC for 24 hours. Fifteen specimens of each substrate were used for the tensile bond test (n = 15) and 5 had the interface analyzed by scanning electron microscopy (SEM). The data was examined by one-way ANOVA and presented no significant differences between groups (p = 0.5787). The mean values obtained for RE, UT and PR were 18.39 ± 9.70, 19.41 ± 7.80, and 23.30 ± 9.37 MPa, respectively. Any dentinal substrates of primary teeth studied are safe for tensile bond strength tests with adhesive systems.

Effectiveness of sealing active proximal caries lesions with an adhesive system: 1-year clinical evaluation

The objective of this study was to evaluate the effectiveness of a therapeutic sealant to arrest non-cavitated proximal carious lesion progression. The study population comprised 44 adolescents who had bitewing radiographs taken for caries diagnosis. Non-cavitated lesions extending up to half of dentin thickness were included in the sample. In the experimental group (n = 33), the proximal caries-lesion surfaces were sealed with an adhesive (OptiBond Solo, Kerr) after tooth separation. The control group (n = 11) received no treatment, except for oral hygiene instructions including use of dental floss. Follow-up radiographs were taken after one year and were analyzed in comparison with baseline radiographs. In a blind study setting, visual readings were performed by two examiners, blinded to whether the examined radiograph was baseline or follow-up, and whether it concerned a test or control lesion. The efficacy of sealing treatment was evaluated by the McNemar test (0.05). About 22% of the sealed lesions showed reduction, 61% showed no change and 16% showed progression. For the control lesions, the corresponding values were 27%, 36% and 36% respectively. The number of lesions that showed reduction and no changes were merged and therefore 83.3% of the sealed lesions and 63.6% of the control lesions were considered clinically successful. No statistical significance was detected (p > 0.05). In the course of 1 year, sealing proximal caries lesions was not shown to be superior to lesion monitoring.