O tratamento da apneia obstrutiva do sono e a utilização de implantes osseointegráveis: revisão da literatura

The obstructive sleep apnea syndrome affects millions of people around the world. The mandibular repositioning devices have been indicated in cases of mild/moderate syndrome; however in edentulous patients its use is deficient since there is no retention. Therefore the objective of this study was to conduct a review on the use of this treatment method combined to osseointegrated implants. A search on the theme: Dental implant and sleep apnea syndromewas performed in the Medline/PubMed, ISI, Cochrane, Dentistry Oral Science, Clinical Trials, Controlled Trials, and Bireme-BvS, databases, and 22 articles were found. After anevaluation 2 studies were selected and the review was complemented with an analysis of randomized controlled trials in the previous seven bases using the key-words: Sleep apnea syndrome, Oral appliance and Randomized controlled trial. The search returned 37 articles, and after they were submitted to inclusion criteria 17 studies were selected. There are a small number of studies presenting the use of dental implants as a mean to assist the stabilization of the mandibular repositioning appliances; those that are available are case reports that focusing on the effectiveness of the technique. Studies examining the effect these appliances in dentate patients indicate improvement in the levels of apnea and snoring. The use of mandibular repositioning appliances in dentate patients is an effective technique in treatment of patients with obstructive sleep apnea syndrome mild/moderate. Randomized controlled trialsare required in order to enable an analysis of the use of mandibular repositioning devices with the aid of dental implants .

Relationship Between Oral Health-Related Quality of Life, Oral Health, Socioeconomic, and General Health Factors in Elderly Brazilians

Objectives To assess the impact of oral health on quality of life in elderly Brazilians and to evaluate its association with clinical oral health measures and socioeconomic and general health factors. Design Cross-sectional study. Setting Population-based cohort study on health, well-being, and aging. Participants Eight hundred fifty-seven participants representing 588,384 community-dwelling elderly adults from the city of Sao Paulo, Brazil. MeasurementS Self-perceived impact of oral health on quality of life was measured using the Geriatric Oral Health Assessment Index (GOHAI), with scores categorized as good, moderate, or poor, indicating low, moderate, and high degrees of negative impact on quality of life, respectively. Results Nearly half of the individuals had good GOHAI scores (44.7% of overall sample, 45.9% of dentate participants, and 43.4% of edentulous participants). In the overall sample, those with poor self-rated general health and a need for dental prostheses were more likely to have poor and moderate GOHAI scores. Individuals with depression were significantly more likely to have poor GOHAI scores. No socioeconomic variables were related to the outcome, except self-perception of sufficient income, which was a protective factor against a poor GOHAI score in dentate participants. Conclusion Moderate and high degrees of negative impact of oral health on quality of life were associated with general health and clinical oral health measures, independent of socioeconomic factors.

The effect of a Lucia jig for 30 minutes on neuromuscular re-programming, in normal subjects

The Lucia jig is a technique that promotes neuromuscular reprogramming of the masticatory system and allows the stabilization of the mandible without the interference of dental contacts, maintaining the mandible position in harmonic condition with the musculature in normal subjects or in patients with temporomandibular dysfunction (TMD). This study aimed to electromyographically analyze the activity (RMS) of the masseter and temporal muscles in normal subjects (control group) during the use of an anterior programming device, the Lucia jig, in place for 0, 5, 10, 20 and 30 minutes to demonstrate its effect on the stomatognathic system. Forty-two healthy dentate individuals (aged 21 to 40 years) with normal occlusion and without parafunctional habits or ternporomandibular dysfunction (RDC/TMD) were evaluated on the basis of the electromyographic activity of the masseter and temporal muscles before placement of a neuromuscular re-programming device, the Lucia jig, on the upper central incisors. There were no statistically significant differences (p < 0.05) in the electromyographic activity of the masticatory muscles in the different time periods. The Lucia jig changed the electromyographic activity by promoting a neuromuscular reprogramming. In most of the time periods, it decreased the activation of the masticatory muscles, showing that this device has wide applicability in dentistry. The use of a Lucia jig over 0, 5, 10, 15, 20 and 30 minutes did not promote any statistically significant increase in muscle activity despite differences in the data, thus showing that this intra-oral device can be used in dentistry.

Factors related to poor self-perceived oral health among community-dwelling elderly individuals in Sao Paulo, Brazil

The present study investigated the prevalence of poor self-perceived oral health and its association with oral health, general health and socioeconomic factors among elderly individuals from Sao Paulo, Brazil. The sample consisted of 871 elderly individuals enrolled in the Health, Wellbeing and Aging cohort study. Self-perceived oral health was measured by the question: "How would you rate your oral health?". Most subjects self-rated their oral health as good. Among dentate individuals, poor oral health was related to depression, poor self-rated health, dental treatment, dental checkups and the psychosocial sub-scale scores of the Geriatric Oral Health Assessment Index. Edentulous individuals were more likely to report poor oral health, whereas those with higher psychosocial scores were less likely to report poor self-rated oral health. Poor self-rated oral health is associated with general health factors and the psychosocial impact of oral health on quality of life, regardless of socioeconomic and clinical health measures.

Neurogenic neuroprotection: Future perspectives

Neurogenic neuroprotection elicited by deep brain stimulation is emerging as a promising approach for treating patients with ischemic brain lesions. In rats, stimulation of the fastigial nucleus, but not dentate nucleus, has been shown to reduce the volume of focal infarction. Protection of neural tissue is a rapid intervention that has a relatively long-lasting effect, rendering fastigial nucleus stimulation (FNS) a potentially valuable method for clinical application. We review some of the main findings of animal experimental research from a clinical perspective. Results: Although the complete mechanisms of neuroprotection induced by FNS remain unclear, important data has been presented in the last two decades. The acute effect of electrical stimulation of the fastigial nucleus is likely mediated by a prolonged opening of potassium channels, and the sustained effect appears to be linked to inhibition of the apoptotic cascade. A better understanding of the cellular and molecular mechanisms underlying neurogenic neuroprotection by stimulation of deep brain nuclei, with special attention to the fastigial nucleus, can contribute toward improving neurological outcomes in ischemic brain insults.

Consequences of pilocarpine-induced status epilepticus in immunodeficient mice

Systemic injection of pilocarpine in rodents induces status epilepticus (SE) and reproduces the main characteristics of temporal lobe epilepsy (TLE). Different mechanisms are activated by SE contributing to cell death and immune system activation. We used BALB/c nude mice, a mutant that is severely immunocompromised, to characterize seizure pattern, neurochemical changes, cell death and c-Fos activation secondarily to pilocarpine-induced SE. The behavioral seizures were less severe in BALB/c nude than in BALB/c wild type mice. However, nude mice presented more tonic clonic episodes and higher mortality rate during SE. The c-Fos expression was most prominent in the caudate-putamen, CA3 (p < 0.05), dentate gyrus, entorhinal cortex (p < 0.001), basolateral nucleus of amygdala (p < 0.01) and piriform cortex (p < 0.05) of BALB/c nude mice than of BALB/c. Besides, nude mice subjected to SE presented high number of Fluorojade-B (FJB) stained cells in the piriform cortex, amygdala (p < 0.05) and hilus (p < 0.05) in comparison with BALB/c mice. A significant increase in the level of glutamate and GABA was found in the hippocampus and cortex of BALB/c mice presenting SE in comparison to controls. However, the level of glutamate was higher in the brains of BALB nude mice than in the brains of BALB/c wild type mice, while the levels of GABA were unchanged. These results indicate that the brains of immunodeficient nude mice are more vulnerable to the deleterious effects of pilocarpine-induced SE as they present intense activation, increased glutamate levels and more cell death. Published by Elsevier B.V.

Masticatory efficiency in class II and class III dentofacial deformities

Masticatory efficiency may be impaired in individuals with dentofacial deformities. The objective of the present study was to determine the condition of masticatory efficiency in individuals with dentofacial deformities. 30 patients with class II (DG-II) and 35 patients with class III (DG-III) dentofacial deformity participated in the study, all had an indication for orthognathic surgery. 30 volunteers (CG) with no alterations of facial morphology or dental occlusion and with no signs or symptoms of temporomandibular joint dysfunction also participated. Masticatory efficiency was analysed using a bead system (colorimetric method). Each individual chewed 4 beads, one at a time, over 20 s measured with a chronometer. The groups were compared in term's of masticatory efficiency using analysis of variance (ANOVA), with the level of significance set at P < 0.05. Masticatory efficiency was significantly greater in CG (P < 0.05) than in DG-II and DG-III in all chewing tasks tested, with no significant difference between DG-II and DG-III (P > 0.05). It was observed that the presence of class II and class III dentofacial deformity affected masticatory efficiency compared to CG, although there was no difference between DG-II and DG-III.

Novelty, but Not Operant Aversive Learning, Enhances Fos and Egr-1 Expression in the Medial Prefrontal Cortex and Hippocampal Areas of Rats

Immediate early genes (IEG) are presumed to be activated in response to stress, novelty, and learning. Evidence supports the involvement of prefrontal and hippocampal areas in stress and learning, but also in the detection of novel events. This study examined whether a previous experience with shocks changes the pattern of Fos and Egr-1 expression in the medial prefrontal cortex (mPFC), the hippocampal cornus ammonis 1 (CA1), and dentate gyrus (DG) of adult male Wistar rats that learned to escape in an operant aversive test. Subjects previously exposed to inescapable footshocks that learned to escape from Shocks were assigned to the treated group (EXP). Subjects from Group Novelty (NOV) rested undisturbed during treatment and also learned to escape in the test. The nonshock group (NSH) rested undisturbed in both sessions. Standard immunohistochemistry procedures were used to detect the proteins in brain sections. The results show that a previous experience with shocks changed the pattern of IEG expression, then demonstrating c-fos and egr-1 induction as experience-dependent events. Compared with NSH and EXP an enhanced Fos expression was detected in the mPFC and CA1 subfield of Group NOV, which also exhibited increased Egr-1 expression in the mPFC and DG in comparison to NSH. No differences were found in the DG for Fos, or in the CA1 for Egr-1. Novelty, and not the operant aversive escape learning, seems to have generated IEG induction. The results suggest novel stimuli as a possible confounding factor in studies on Fos and/or Egr-1 expression in aversive conditions.

Texture analysis of high resolution MRI allows discrimination between febrile and afebrile initial precipitating injury in mesial temporal sclerosis

A computational pipeline combining texture analysis and pattern classification algorithms was developed for investigating associations between high-resolution MRI features and histological data. This methodology was tested in the study of dentate gyrus images of sclerotic hippocampi resected from refractory epilepsy patients. Images were acquired using a simple surface coil in a 3.0T MRI scanner. All specimens were subsequently submitted to histological semiquantitative evaluation. The computational pipeline was applied for classifying pixels according to: a) dentate gyrus histological parameters and b) patients' febrile or afebrile initial precipitating insult history. The pipeline results for febrile and afebrile patients achieved 70% classification accuracy, with 78% sensitivity and 80% specificity [area under the reader observer characteristics (ROC) curve: 0.89]. The analysis of the histological data alone was not sufficient to achieve significant power to separate febrile and afebrile groups. Interesting enough, the results from our approach did not show significant correlation with histological parameters (which per se were not enough to classify patient groups). These results showed the potential of adding computational texture analysis together with classification methods for detecting subtle MRI signal differences, a method sufficient to provide good clinical classification. A wide range of applications of this pipeline can also be used in other areas of medical imaging. Magn Reson Med, 2012. (c) 2012 Wiley Periodicals, Inc.

Manganese-enhanced magnetic resonance imaging detects mossy fiber sprouting in the pilocarpine model of epilepsy

Purpose: Mossy fiber sprouting (MFS) is a frequent finding following status epilepticus (SE). The present study aimed to test the feasibility of using manganese-enhanced magnetic resonance imaging (MEMRI) to detect MFS in the chronic phase of the well-established pilocarpine (Pilo) rat model of temporal lobe epilepsy (TLE). Methods: To modulate MFS, cycloheximide (CHX), a protein synthesis inhibitor, was coadministered with Pilo in a subgroup of animals. In vivo MEMRI was performed 3 months after induction of SE and compared to the neo-Timm histologic labeling of zinc mossy fiber terminals in the dentate gyrus (DG). Key Findings: Chronically epileptic rats displaying MFS as detected by neo-Timm histology had a hyperintense MEMRI signal in the DG, whereas chronically epileptic animals that did not display MFS had minimal MEMRI signal enhancement compared to nonepileptic control animals. A strong correlation (r = 0.81, p < 0.001) was found between MEMRI signal enhancement and MFS. Significance: This study shows that MEMRI is an attractive noninvasive method for detection of mossy fiber sprouting in vivo and can be used as an evaluation tool in testing therapeutic approaches to manage chronic epilepsy.

SCG postnatal remodelling - hypertrophy and neuron number stability - in Spix's Yellow-toothed Cavies (Galea spixii)

Whilst a fall in neuron numbers seems a common pattern during postnatal development, several authors have nonetheless reported an increase in neuron number, which may be associated with any one of a number of possible processes encapsulating either neurogenesis or late maturation and incomplete differentiation. Recent publications have thus added further fuel to the notion that a postnatal neurogenesis may indeed exist in sympathetic ganglia. In the light of these uncertainties surrounding the effects exerted by postnatal development on the number of superior cervical ganglion (SCG) neurons, we have used state-of-the-art design-based stereology to investigate the quantitative structure of SCG at four distinct timepoints after birth, viz., 1-3 days, 1 month, 12 months and 36 months. The main effects exerted by ageing on the SCG structure were: (i) a 77% increase in ganglion volume; (ii) stability in the total number of the whole population of SCG nerve cells (no change - either increase or decrease) during post-natal development; (iii) a higher proportion of uninucleate neurons to binucleate neurons only in newborn animals; (iv) a 130% increase in the volume of uninucleate cell bodies; and (v) the presence of BrdU positive neurons in animals at all ages. At the time of writing our results support the idea that neurogenesis takes place in the SCG of preas, albeit it warrants confirmation by further markers. We also hypothesise that a portfolio of other mechanisms: cell repair, maturation, differentiation and death may be equally intertwined and implicated in the numerical stability of SCG neurons during postnatal development. (C) 2011 ISDN. Published by Elsevier Ltd. All rights reserved.

Factors related to poor self-perceived oral health among community-dwelling elderly individuals in São Paulo, Brazil

The present study investigated the prevalence of poor self-perceived oral health and its association with oral health, general health and socioeconomic factors among elderly individuals from São Paulo, Brazil. The sample consisted of 871 elderly individuals enrolled in the Health, Wellbeing and Aging cohort study. Self-perceived oral health was measured by the question: "How would you rate your oral health?". Most subjects self-rated their oral health as good. Among dentate individuals, poor oral health was related to depression, poor self-rated health, dental treatment, dental checkups and the psychosocial subscale scores of the Geriatric Oral Health Assessment Index. Edentulous individuals were more likely to report poor oral health, whereas those with higher psychosocial scores were less likely to report poor self-rated oral health. Poor self-rated oral health is associated with general health factors and the psychosocial impact of oral health on quality of life, regardless of socioeconomic and clinical health measures.

Chronic unpredictable mild stress alters an anxiety-related defensive response, Fos immunoreactivity and hippocampal adult neurogenesis

Previous results show that elevated T-maze (ETM) avoidance responses are facilitated by acute restraint. Escape, on the other hand, was unaltered. To examine if the magnitude of the stressor is an important factor influencing these results, we investigated the effects of unpredictable chronic mild stress (UCMS) on ETM avoidance and escape measurements. Analysis of Fos protein immunoreactivity (Fos-ir) was used to map areas activated by stress exposure in response to ETM avoidance and escape performance. Additionally, the effects of the UCMS protocol on the number of cells expressing the marker of migrating neuroblasts doublecortin (DCX) in the hippocampus were investigated. Corticosterone serum levels were also measured. Results showed that UCMS facilitates ETM avoidance, not altering escape. In unstressed animals, avoidance performance increases Fos-ir in the cingulate cortex, hippocampus (dentate gyrus) and basomedial amygdala, and escape increases Fos-ir in the dorsolateral periaqueductal gray and locus ceruleus. In stressed animals submitted to ETM avoidance, increases in Fos-ir were observed in the cingulate cortex, ventrolateral septum, hippocampus, hypothalamus, amygdala, dorsal and median raphe nuclei. In stressed animals submitted to ETM escape, increases in Fos-ir were observed in the cingulate cortex, periaqueductal gray and locus ceruleus. Also, UCMS exposure decreased the number of DCX-positive cells in the dorsal and ventral hippocampus and increased corticosterone serum levels. These data suggest that the anxiogenic effects of UCMS are related to the activation of specific neurobiological circuits that modulate anxiety and confirm that this stress protocol activates the hypothalamus-pituitary-adrenal axis and decreases hippocampal adult neurogenesis.

Analisi e valutazione delle performance acustiche degli aeromobili nella fase di atterraggio

Nella tesi si analizzano le principali fonti del rumore aeronautico, lo stato dell'arte dal punto di vista normativo, tecnologico e procedurale. Si analizza lo stato dell'arte anche riguardo alla classificazione degli aeromobili, proponendo un nuovo indice prestazionale in alternativa a quello indicato dalla metodologia di certificazione (AC36-ICAO) Allo scopo di diminuire l'impatto acustico degli aeromobili in fase di atterraggio, si analizzano col programma INM i benefici di procedure CDA a 3° rispetto alle procedure tradizionali e, di seguito di procedure CDA ad angoli maggiori in termini di riduzione di lunghezza e di area delle isofoniche SEL85, SEL80 e SEL75.

Le funzioni wavelet nelle applicazioni scientifiche

Le wavelet sono una nuova famiglia di funzioni matematiche che permettono di decomporre una data funzione nelle sue diverse componenti in frequenza. Esse combinano le proprietà dell’ortogonalità, il supporto compatto, la localizzazione in tempo e frequenza e algoritmi veloci. Sono considerate, perciò, uno strumento versatile sia per il contenuto matematico, sia per le applicazioni. Nell’ultimo decennio si sono diffuse e imposte come uno degli strumenti migliori nell’analisi dei segnali, a fianco, o addirittura come sostitute, dei metodi di Fourier. Si parte dalla nascita di esse (1807) attribuita a J. Fourier, si considera la wavelet di A. Haar (1909) per poi incentrare l’attenzione sugli anni ’80, in cui J. Morlet e A. Grossmann definiscono compiutamente le wavelet nel campo della fisica quantistica. Altri matematici e scienziati, nel corso del Novecento, danno il loro contributo a questo tipo di funzioni matematiche. Tra tutti emerge il lavoro (1987) della matematica e fisica belga, I. Daubechies, che propone le wavelet a supporto compatto, considerate la pietra miliare delle applicazioni wavelet moderne. Dopo una trattazione matematica delle wavalet, dei relativi algoritmi e del confronto con il metodo di Fourier, si passano in rassegna le principali applicazioni di esse nei vari campi: compressione delle impronte digitali, compressione delle immagini, medicina, finanza, astonomia, ecc. . . . Si riserva maggiore attenzione ed approfondimento alle applicazioni delle wavelet in campo sonoro, relativamente alla compressione audio, alla rimozione del rumore e alle tecniche di rappresentazione del segnale. In conclusione si accenna ai possibili sviluppi e impieghi delle wavelet nel futuro.