Investigation du rôle de Myo9b dans la migration des interneurones GABAergiques corticaux

Les encéphalopathies épileptogènes sont des maladies graves de l’enfance associant une épilepsie, souvent réfractaire, et un retard de développement. Les mécanismes sous-tendant ces maladies sont peu connus. Cependant, nous postulons que ces épilepsies puissent être causées par une dysfonction du réseau inhibiteur. En effet, des défauts de migration ou de maturation des interneurones GABAergiques (INs) corticaux induisent l’épilepsie, tant chez l’humain que chez la souris. Dans le but d’étudier les causes génétiques des encéphalopathies épileptogènes sporadiques inexpliquées, le laboratoire de la Dre Rossignol a procédé au séquençage d’exome entier d’une cohorte d’enfants atteints. Cela a permis d’identifier, chez un patient, une nouvelle mutation de novo, possiblement pathogène, dans le gène MYO9b. MYO9b est impliqué dans la migration de cellules immunitaires et cancéreuses et est exprimée durant le développement cérébral. Nous émettons l’hypothèse voulant que MYO9b puisse être importante pour la migration des INs corticaux. Les résultats présentés dans ce mémoire démontrent que Myo9b est exprimé dès le stade embryonnaire par les progéniteurs des INs corticaux et que son expression se restreint aux INs dans le cortex mature. De plus, nous démontrons que la répression ex vivo de Myo9b sélectivement dans les INs au sein de tranches corticales organotypiques embryonnaires mène à des défauts morphologiques majeurs de ces cellules en migration. En effet, ces cellules présentent une morphologie multipolaire et des neurites rostraux plus longs et plus complexes. Ces changements morphologiques pourraient avoir un impact majeur sur la migration des INs et ainsi perturber le développement des réseaux inhibiteurs.

Soluciones hipertónicas en trauma craneoencefálico: revisión sistemática de la literatura

El traumatismo craneoencefálico, es la epidemia silenciosa de nuestra época, que genera gastos en salud, en países como Estados Unidos, cercanos a los 60 billones de dólares anuales, y cerca de 400 billones en rehabilitación de los discapacitados. El pilar del manejo médico del trauma craneoencefálico moderado o severo, es la osmoterapia, principalmente con sustancias como el manitol y las soluciones hipertónicas. Se realizó la revisión de 14 bases de datos, encontrando 4657754 artículos, quedando al final 40 artículos después de un análisis exhaustivo, que se relacionaban con el manejo de la hipertensión endocraneana y terapia osmótica. Resultados: Se compararon diferentes estudios, encontrando gran variabilidad estos, sin homogenización en los análisis estadísticos, y la poca rigurosidad no permitieron, la recolección de datos y la comparación entre los diferentes estudios, no permitió realizar el meta-análisis y por esto se decidió la realización de una revisión sistemática de la literatura. Se evidenció principalmente tres cosas: la primera es la poca rigurosidad con la que se realizan los estudios clínicos; la segunda, es que aún falta mucha más investigación principalmente, la presencia de estudios clínicos aleatorizados multicéntricos, que logren dar una sólida evidencia y que genere validez científica que se requiere, a pesar de la evidencia clara en la práctica clínica; la tercera es la seguridad para su uso, con poca presencia de complicaciones para las soluciones salinas hipertónicas.

Factors relacionats amb l'ús del casc en adolescents i aspectes canviants després d'un accident amb ciclomotor

Les lesions cerebrals per traumatismes craniencefàlics són la causa més freqüent de defunció en els accidents de trànsit en els que estan implicats vehicles de dues rodes. Malgrat la provada eficàcia de l'ús del casc per amortir les lesions en cas d'accidents, molts adolescents i joves no el fan servir o fan un ús incorrecte. El principal objectiu d'aquesta investigació és identificar les variables que millor prediuen l'ús del casc entre els adolescents. En la recerca es combinen la metodologia quantitativa i qualitativa i consta de dues fases. A la primera fase participen 876 estudiants de secundària (46,8% nois) amb edats compreses entre 14 i 18 anys. A la segona fase, s'estudien quatre casos d'adolescents que han patit un accident greu circulant amb ciclomotor i que no portaven el casc o feien un ús incorrecte. Els resultats suggereixen que l'edat i la influència social són les variables més rellevants per predir l'ús continuat del casc entre els adolescents. De l'estudi se'n deriven estratègies d'intervenció per incrementar l'ús del casc entre els dolescents.

Influence of rhBMP-2 on bone formation and osseointegration in different implant systems after sinus-floor elevation. An in vivo study on sheep

Background Several studies have reported certain bone morphogenic proteins (BMPs) to have positive effects on bone generation Although some investigators have studied the effects of human recombinant BMP (rhBMP-2) in sinus augmentation in sheep, none of these studies looked at the placement of implants at the time of sinus augmentation Furthermore, no literature could be found to report on the impact that different implant systems, as well as the positioning of the implants had on bone formation if rhBMP-2 was utilized in sinus-lift procedures Purpose The aim of this study was to compare sinus augmentation with rhBMP-2 on a poly-D, L-lactic-co-glycolic acid gelatine (PLPG) sponge with sinus augmentation with autologous pelvic cancellous bone in the maxillary sinus during the placement of different dental Implants Materials and methods Nine adult female sheep were submitted to bilateral sinus-floor elevation In one side (test group) the sinus lift was performed with rhBMP-2 on a PLPG-sponge, while the contralateral side served as the control by using cancellous bone from the iliac crest Three different implants (Branemark (R), 31 (R) and Straumann (R)) were inserted either simultaneously with the sinus augmentation or as a two staged procedure 6 weeks later The animals were sacrificed at 6 and 12 weeks for histological and histomorphometrical evaluations during which bone-to-implant contact (BIC) and bone density (BD) were evaluated Results BD and BIC were significantly higher at 12 weeks in the test group if the Implants were placed at the time of the sinus lift (p < 0 05) No difference was observed between the different implant systems or positions Conclusions The use of rhBMP-2 with PLPG-sponge increased BIC as well as BD in the augmented sinuses if compared to autologous bone Different implant systems and positions of the implants had no effect on BIC or BD (C) 2010 European Association for Cranio-Maxillo-Facial Surgery

Evaluation of Low Intensity Laser Therapy In Myofascial Pain Syndrome

Limited studies have demonstrated that low intensity laser therapy (LILT) may have a therapeutic effect on the treatment of myofascial pain syndrome (MPS). Sixty (60) patients with MPS and having one active trigger point in the anterior masseter and anterior temporal muscles were selected and assigned randomly to six groups (n=10): Groups I to III were treated with GaAIAS (780 nm) laser, applied in continuous mode and in a meticulous way, twice a week, for four weeks. Energy was set to 25 J/cm(2), 60 J/cm2 and 105 J/cm2, respectively. Groups IV to VI were treated with placebo applications, simulating the same parameters as the treated groups. Pain scores were assessed just before, then immediately after the fourth application, immediately after the eighth application, at 15 days and one month following treatment. A significant pain reduction was observed over time (p<0.001). The analgesic effect of the LILT was similar to the placebo groups. Using the parameters described in this experiment, LILT was effective in reducing pain experienced by patients with myofascial pain syndrome. Thus, it was not possible to establish a treatment protocol. Analyzing the analgesic effect of LILT suggests it as a possible treatment of MPS and may help to establish a clinical protocol for this therapeutic modality.

Electromyographic Evaluation of Neuromuscular Coordination of Subject After Orthodontic Intervention

The aim of this work was to investigate the neuromuscular changes associated with the orthodontic post-treatment using surface electromyography. One hundred (100) young, healthy adults without signs and symptoms of temporomandibular dysfunction (TMD) were divided into two groups: 60 subjects who were undergoing orthodontic intervention (Ortho Group) and 40 subjects who had no orthodontic intervention (Control Group), aged 18-25 years. EMG activity of masseter and temporalis anterior muscle was recorded during two different tests: 1. maximum voluntary clench (MVC) with cotton rolls; and 2. MVC in intercuspal position. In all subjects, both tests were performed with symmetric muscular patterns (more than 85%) and with insignificant latero-deviating of the mandible (lower than 10%). There are no statistically significant differences between the subjects of both groups evaluated. Both groups showed medium index values calculated according to the normal standards established previously.

Characteristics of TMD noise analyzed by electrovibratography

Studying joint noise is an important parameter for diagnosing temporomandibular dysfunction. In this study, eight groups (n=9) were formed according to joint dysfunction classification, provided by employing vibration analysis equipment. Parameters for analyzing joint noise were: total vibration energy, peak amplitude, and peak frequency. Mouth opening range was also analyzed. Statistical analysis results for each parameter were significant at 1 %. Each analyzed group presented different noise characteristics. This allowed for inclusion of the groups within a determined value category. The patient group with normal condyle/disk relationship always presented the lowest values. The type of joint noise was characterized by analyzing total integral noise, peak amplitude, peak frequency, and mouth opening. Analyzing joint noise using electrovibratography suggests the type of joint dysfunction and may help to establish a diagnosis, as well as a treatment plan.

Evolução morfométrica dos anexos embrionários e fetais bovinos obtidos por monta natural, com 10 a 70 dias da gestação

O período inicial da gestação de bovinos é caracterizado por grandes perdas embrionárias. Considerando a importância deste fator no âmbito da reprodução animal foram estudados os anexos embrionários e fetais bovinos fecundados por monta natural de 15-70 dias de gestação, com o objetivo de estabelecer parâmetros morfométricos da placenta na fase inicial da gestação. Com uso de um paquímetro foram realizadas mensurações do comprimento (crânio caudal), largura (latero lateral) e altura (dorso ventral) das membranas corioalantóide e amniótica. O início da formação dos cotilédones foi observado e quantificado, assim como, o peso placentário. O peso médio do saco gestacional aumentou com o evoluir da idade gestacional, entretanto, o crescimento foi acelerado a partir de 20-30 dias de gestação. O comprimento crânio caudal e dorso ventral da membrana corioalantóide e do âmnio apresentaram crescimento lento e gradual com o evoluir dos períodos gestacionais analisados. Com 30-40 dias de gestação, os primeiro cotilédones já eram visualizados e contatos com facilidade na superfície coriônica. Os períodos de crescimento coincidiram com os maiores índices de perdas gestacionais em bovinos. Os parâmetros aqui analisados poderão servir para futuras investigações dos anexos embrionários de organismos manipulados em laboratório.

Electromyographic analysis of the masseter and buccinator muscles with the Pro-Fono Facial Exerciser use in bruxers

The aim of this study was to evaluate the efficiency of the Pro-Fono Facial Exerciser (Pro-Fono Productos Especializaclos para Fonoaudiologia Ltda.., Barueri/SP, Brazil) to decrease bruxism, as well as the correlation between the masseter and the buccinator muscles using electromyography (EMG). In this study, 39 individuals ranging from 23 to 48 years of age were selected from a dental school and then underwent surface EMG at three different periods of time: 0, 10, and 70 days. They were divided into a normal control group, a bruxer control group (without device), and an experimental bruxer group who used the device. The bruxer group showed a greater masseter EMG amplitude when compared to the normal group, while the experimental group had deceased activity with a reduction in symptoms. The buccinator EMG spectral analysis of the experimental bruxist group showed asynchronous contractions of the masseter muscle (during jaw opening) after using the Pr6-Fono Facial Exerciser. The normal group also showed asynchronous contractions. Upon correlation of the data between these muscles, the inference is that there is a reduction in bruxism when activating the buccinator muscle.

Clinical evaluation of the bicoronal flap in the treatment of facial fractures. Retrospective study of 132 patients

The aim of the present study was to evaluate the postoperative complications of bicoronal flaps used to treat facial fractures. One hundred and thirty two patients that received bicoronal flaps for the treatment of upper and middle third facial fractures were called for clinical and radiographic examination. Minimum follow-up was 1 year and all patients had charts with adequate information about their perioperative care pertinent to the study. Results showed as complications hypoesthesia (17%), partial unilateral frontal motor deficit (11%), infection (3%), hypertrophic scars (3%), varying degrees of alopecia (18%), seroma or hematoma in the immediate postoperative period (5%). The flap provided wide surgical access to the upper and middle facial thirds with very few serious complications, most frequently allowing good aesthetic results. (C) 2011 European Association for Cranio-Maxillo-Facial Surgery.

In vitro comparison of 1.5 mm vs. 2.0 mm screws for fixation in the sagittal split osteotomy

Purpose: Numerous "in vitro" investigations have been conducted to evaluate the role of screw size and pattern in determining optimal resistance to deformation, often these have been controversial. The aim of this study was to evaluate the effect of screw size and insertion technique on the stability of sagittal split osteotomies.Materials and methods: This study used twenty polyurethane replicas of human hemimandibles with a prefabricated sagittal split ramus osteotomy (SSRO). The hemimandibles were stabilized with 1.5 mm and 2.0 mm titanium screws inserted in an inverted L configuration. All specimens were tested to determine the strength and stability of the fixation.Results: In all cases there was failure of the synthetic bone before there was any evidence of screw failure. There were no significant differences in the load necessary to make the construct fail between the 1.5 or 2.0 mm screw sizes.Conclusion: There was no statistically significant difference between the strengths achieved with screws of 1.5 and 2.0 mm diameters for fixation of SSRO performed in synthetic mandibles. There was no fracture of the 1.5 mm or 2.0 mm diameter screws in any of the tests. 1.5 mm diameter screws in an inverted L pattern have as much stability and mechanical resistance as a 2.0 mm screw, may be safely used for this procedure. (C) 2010 European Association for Cranio-Maxillo-Facial Surgery.

Multiscale Fractal Descriptors and Polynomial Classifier for Partial Pixels Identification in Regions of Interest of Mammographic Images

Computer systems are used to support breast cancer diagnosis, with decisions taken from measurements carried out in regions of interest (ROIs). We show that support decisions obtained from square or rectangular ROIs can to include background regions with different behavior of healthy or diseased tissues. In this study, the background regions were identified as Partial Pixels (PP), obtained with a multilevel method of segmentation based on maximum entropy. The behaviors of healthy, diseased and partial tissues were quantified by fractal dimension and multiscale lacunarity, calculated through signatures of textures. The separability of groups was achieved using a polynomial classifier. The polynomials have powerful approximation properties as classifiers to treat characteristics linearly separable or not. This proposed method allowed quantifying the ROIs investigated and demonstrated that different behaviors are obtained, with distinctions of 90% for images obtained in the Cranio-caudal (CC) and Mediolateral Oblique (MLO) views.

The influence of local administration of simvastatin in calvarial bone healing in rats

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

Kinesiographic study of deglutition in dentate individuals and complete denture wearers

Swallowing is used as a clinical method in prosthodontics to determine and record jaw relationships. The aim of this study was to perform a quantitative evaluation, in naturally dentate subjects and complete denture wearers, of three measurements associated with the mandibular position during the act of swallowing water: 1. intermaxillary distance on vertical axis; 2. anteroposterior deviation; and 3. lateral deviation. Two groups were selected: Group I (GI) included 40 subjects with complete dentition (mean age 45.27 yrs) and Group II (GII) included 40 bimaxillary edentate subjects, complete denture wearers (mean age 63.92 yrs). A kinesiographic instrument was used for analysis. Three records were taken for each measurement and a mean value obtained. It was concluded that: 1. intermaxillary distance on vertical axis and horizontal deviation were similar for both groups; 2. there was a significant intermaxillary distance on the vertical axis; and 3. for anteroposterior and lateral axis, results showed moderate deviation in relation to maximal intercuspation (MI).

Multidisciplinary approach to chronic pain from myofascial pain dysfunction syndrome: A four-year experience at a Brazilian center

Chronic pain is the major complaint of myofascial pain dysfunction syndrome (MPDS) and is a complex problem which involves physical, psychological and social aspects, the etiology of MPDS is multifactorial and the multidisciplinary approach is essential for differential diagnosis and for comprehensive treatment planning, In 1993, the Dental School of Piracicaba-UNICAMP, Brazil, opened a Center for Pain Studies (CPS), staffed by health care providers including, dentists, psychologists, physicians, physiotherapists and phonoaudiologists. The major aims of the CPS are to provide clinical care and to develop basic and applied research, Sixty-two MPDS patients had been admitted to the CPS by 1997, There were 60 females and 2 males, mean age -32.5 years, the mean duration of chronic pain was 48 months. Pain intensity and unpleasantness were measured employing the Visual Analogue Scale, the tendency to develop stress-related diseases was assessed by the Social Readjustment de Scale, There was a mean reduction of chronic pain of 69.89% and 71.78% relative to intensity and unpleasantness, respectively, the experience of clinical attendance at a multidisciplinary center showed the relevance of a team consisting of health care providers from different specialties with well-established aims, completely integrated and sensitive enough to understand the painful complaints of MPDS patients.