905 resultados para Nasal cavity


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Primary olfactory neurons project axons from the olfactory neuroepithelium lining the nasal cavity to,the olfactory bulb in the brain. These axons grow within large mixed bundles in the olfactory nerve and then sort out into homotypic fascicles in the nerve fiber layer of the olfactory bulb before terminating in topographically fixed glomeruli. Carbohydrates expressed on the cell surface have been implicated in axon sorting within the nerve fiber layer. We have identified two novel subpopulations of primary olfactory neurons that express distinct alpha-extended lactoseries carbohydrates recognised by monoclonal antibodies LA4 and KH10. Both carbohydrate epitopes are present on novel glycoforms of the neural cell adhesion molecule, which we have named NOC-7 and NOC-8. Primary axon fasciculation is disrupted in vitro when interactions between these cell surface lactoseries carbohydrates and their endogenous binding molecules are inhibited by the LA4 and KH10 antibodies or lactosamine sugars. We report the expression of multiple members of the lactoseries binding galectin family in the primary olfactory system. In particular, galectin-3 is expressed by ensheathing cells surrounding nerve fascicles in the submucosa and nerve fiber layer, where it may mediate cross-linking of axons. Galectin-4, -7, and -8 are expressed by the primary olfactory axons as they grow from the nasal cavity to the olfactory bulb. A putative role for NOC-7 and NOC-8 in axon fasciculation and the expression of multiple galectins in the developing olfactory nerve suggest that these molecules may be involved in the formation of this pathway, particularly in the sorting of axons as they converge towards their target. (C) 2004Wiley-Liss, Inc.

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Este estudo avaliou a estabilidade das alterações dentárias e esqueléticas produzidas pela Expansão Rápida da Maxila Assistida Cirurgicamente (ERMAC), no sentido transversal e vertical. A amostra selecionada para este estudo retrospectivo foi composta de 60 telerradiografias em norma frontal, de 15 pacientes, sendo 6 do sexo masculino e 9 do sexo feminino, com média de idade de 23 anos e 3 meses. Utilizou-se o disjuntor tipo Hyrax e o procedimento cirúrgico foi caracterizado pela osteotomia sagital mediana da maxila e não abordagem da sutura pterigopalatina. O início da ativação ocorreu no terceiro dia pós-operatório, sendo que, os limites para a expansão foram determinados por critérios eminentemente clínicos. Todos os pacientes foram radiografados nas fases pré-expansão (T1), pós-expansão imediata (T2), 3 meses pós- expansão (com o próprio disjuntor como contenção) (T3) e 6 meses pós-expansão (com a placa de acrílico removível como contenção) (T4). Medidas lineares foram obtidas a partir dos traçados cefalométricos gerados por um programa computadorizado (Radiocef Studio 2) e analisadas estatisticamente pelo teste de variância (ANOVA) e Tukey ao nível de 5% de significância. Concluiu-se que a ERMAC produziu um aumento estatisticamente significante, da cavidade nasal, largura maxilar, distância intermolares superiores, de T1 para T2, e que se mantiveram em T3 e T4. A largura facial e as distâncias intermolares inferiores não apresentaram alterações após a ERMAC. Avaliando o comportamento vertical da face, notou-se um aumento da AFAI nos tempos T1 para T2 que, diminuiu após a contenção de 3 meses (T3) e permaneceu estável em T4, embora aumentada se comparada com T1.(AU)

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O objetivo desta pesquisa constituiu em avaliar, por meio das telerradiografias posteroanteriores, as alterações transversais promovidas pelo aparelho Frankel-2 em pacientes com maloclusão de Classe II, divisão 1, além de verificar a estabilidade das mesmas após um período médio de 7,11 anos pós-tratamento. A amostra compreendeu um total de 45 telerradiografias posteroanteriores provenientes de 15 pacientes tratados com o RF-2, realizadas em três fases: (T1) início do tratamento; (T2) final de tratamento; (T3) pós-tratamento. Foram avaliadas outras 36 telerradiografias posteroanteriores de 18 pacientes não tratados (grupo controle), acompanhados num período correspondente ao tratamento (T1-T2). As telerradiografias foram digitalizadas e foi utilizado o software Radiocef Studio 2 para realizar as mensurações das medidas cefalométricas. Para a comparação entre as alterações ocorridas no grupo tratado e no grupo controle, foi aplicado o teste t não pareado. Já para as modificações nas fases inicial, final e pós-tratamento no grupo tratado, foi empregada a Análise de Variância seguida do teste de comparações múltiplas de Tukey, com o valor crítico de 0,05. Os resultados mostraram que durante o período de tratamento as distâncias intercaninos inferiores e intermolares superiores aumentaram de forma estatisticamente significante. Já as distâncias que representam a largura da cavidade nasal, altura facial inferior, largura mandibular e distância intermolares inferiores não sofreram alterações estatisticamente significantes. No período pós-tratamento, observou-se uma suave redução nas distâncias intercaninos inferiores e intermolares superiores. Porém, considerando-se as alterações ocorridas devido ao crescimento e desenvolvimento transversal dos arcos dentários no período analisado, em que haveria uma redução destas distâncias, provavelmente houve uma estabilidade relativa das alterações dentárias transversais promovidas pelo RF-2. Portanto, pode-se concluir que o RF-2 não possui qualquer efeito esquelético transversal. Contudo, há um aumento das distâncias intermolares superiores e intercaninos inferiores durante o tratamento, que permanece relativamente estável, considerando-se as alterações ocorridas pelo crescimento e desenvolvimento normal dos arcos dentários.

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The aim of this study was to develop and characterize an intranasal delivery system for amantadine hydrochloride (AMT). Optimal formulations consisted of a thermosensitive polymer Pluronic® 127 and either carboxymethyl cellulose or chitosan which demonstrated gel transition at nasal cavity temperatures (34 ± 1°C). Rheologically, the loss tangent (Tan δ) confirmed a 3-stage gelation phenomena at 34 ± 1°C and non-Newtonian behavior. Storage of optimized formulation carboxymethyl cellulose and optimal formulation chitosan at 4°C for 8 weeks resulted in repeatable release profiles at 34°C when sampled, with a Fickian mechanism earlier on but moving toward anomalous transport by week 8. Polymers (Pluronic® 127, carboxymethyl cellulose, and chitosan) demonstrated no significant cellular toxicity to human nasal epithelial cells up to 4 mg/mL and up to 1 mM for AMT (IC50: 4.5 ± 0.05 mM). Optimized formulation carboxymethyl cellulose and optimal formulation chitosan demonstrated slower release across an in vitro human nasal airway model (43%-44% vs 79 ± 4.58% for AMT). Using a human nasal cast model, deposition into the olfactory regions (potential nose-to-brain) was demonstrated on nozzle insertion (5 mm), whereas tilting of the head forward (15°) resulted in greater deposition in the bulk of the nasal cavity.

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Rhinoscleroma is a chronic granulomatous infectious disease that is rare in Western Europe. We report the case of a 5-year-old Portuguese boy diagnosed with rhinoscleroma in the context of recurrent epistaxis. He had a 6-month course of antibiotic (amoxicillin plus clavulanate) therapy with full recovery.

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Introdução: O melanoma maligno da mucosa (MMM) é uma doença rara com mau prognóstico. Material e Métodos: Estudo retrospetivo de 32 doentes do Instituto Português de Oncologia Francisco Gentil de Lisboa com MMM da cabeça e pescoço, no período de 1998 a 2012. Resultados: Dos 32 casos analisados a idade média foi de 70 anos. O tumor primário localizou-se na cavidade nasal e seios peri-nasais em 24 doentes e na cavidade oral em 8 casos. A maioria dos doentes (23) foi submetida a tratamento cirúrgico. Destes, 16 foram propostos para terapêutica complementar com Radioterapia. O tempo de seguimento variou de 26 dias a 10 anos. A sobrevida aos 5 anos foi de 18%. Conclusões: A maioria dos doentes apresentou um estadio avançado na altura do diagnóstico e, apesar dos tratamentos instituídos, verificou-se uma elevada mortalidade. O tratamento de escolha é a cirurgia. O papel da radioterapia continua a ser controverso.

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Aim Review the literature from 1990 to 2013 to determine known anatomic sites, risk factors, treatments, and outcomes of head and neck squamous cell carcinoma (HNSCC) in sub-Saharan Africa. Methods Using a systematic search strategy, literature pertaining to HNSCC in sub-Saharan Africa was reviewed and patient demographics, anatomic sites, histology, stage, treatment, and outcomes were abstracted. The contributions of human immunodeficiency virus (HIV), human papillomavirus (HPV) and behavioural risk factors to HNSCC in the region were assessed. Results Of the 342 papers identified, 46 were utilized for review, including 8611 patients. In sub-Saharan Africa, the oropharyngeal/oral cavity was found to be the most common site, with 7750 cases (90% of all cases). Few papers distinguished oropharyngeal from oral cavity, making identification of possible HPV-associated oropharyngeal squamous cell carcinoma (SCC) difficult. SCC of the nasopharynx, nasal cavity, or paranasal sinuses was identified in 410 patients (4.8% of all cases). Laryngeal SCC was found in 385 patients (4.5% of all cases), and only 66 patients (0.8% of all cases) with hypopharyngeal SCC were identified. In 862 patients with data available, 43% used tobacco and 42% used alcohol, and reported use varied widely and was more common in laryngeal SCC than that of the oropharyngeal/oral cavity. Toombak and kola nut use was reported to be higher in patients with HNSCC. Several papers reported HIV-positive patients with HNSCC, but it was not possible to determine HNSCC prevalence in HIV-positive compared to negative patients. Reports of treatment and outcomes were rare. Conclusions The oropharyngeal/oral cavity was by far the most commonly reported site of HNSCC reported in sub-Saharan Africa. The roles of risk factors in HNSCC incidence in sub-Saharan Africa were difficult to delineate from the available studies, but a majority of patients did not use tobacco and alcohol.

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The objective of the current study was to analyze the effects of rhinoseptoplasty on internal nasal dimensions and speech resonance of individuals with unilateral cleft lip and palate, estimated by acoustic rhinometry and nasometry, respectively. Twenty-one individuals (aged 15-46 years) with previously repaired unilateral cleft lip and palate were analyzed before (PRE), and 6 to 9 (POST1) and 12 to 18 months (POST2) after surgery. Acoustic rhinometry was used to measure the cross-sectional areas (CSAs) of segments corresponding to the nasal valve (CSA1), anterior portion (CSA2), and posterior portion (CSA3) of the lower turbinate, and the volumes at the nasal valve (V1) and turbinate (V2) regions at cleft and noncleft sides, before and after nasal decongestion with a topical vasoconstrictor. Nasometry was used to evaluate speech nasalance during the reading of a set of sentences containing nasal sounds and other devoid of nasal sounds. At the cleft side, before nasal decongestion, there was a significant increase (P < 0.05) in mean CSA1 and V1 values at POST1 and POST2 compared with PRE. After decongestion, increased values were also observed for CSA2 and V2 at POST2. No significant changes were observed at the noncleft side. Mean nasalance values at PRE, POST1, an POST2 were not different from each other in both oral and nasal sentences. The measurement of CSAs and volumes by acoustic rhinometry revealed that rhinoseptoplasty provided, in most cases analyzed, a significant increase in nasal patency, without concomitant changes in speech resonance, as estimated by nasalance assessment.

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O linfoma de células natural killers (NK)/T extranodal é um tumor maligno agressivo com características clinicopatológicas distintas, caracterizadas por invasão e destruição vasculares, necrose proeminente, fenótipo linfocítico citotóxico e uma forte associação com o vírus Epstein-Barr. Relatamos aqui um caso de linfoma de células NK/T nasal extranodal, envolvendo o seio maxilar, assoalho de órbita, e interessantemente estendendo-se para a cavidade oral através do osso alveolar e mucosa vestibular, preservando o palato, levando a um diagnóstico inicial equivocado de doença periodontal agressiva. Ainda, nós investigamos pela primeira vez a expressão imunoistoquímica das proteínas Fatty acid sinthase (FASN) e glucose transporter 1 (GLUT-1) nesta neoplasia. FASN revelou uma forte expressão citoplasmática nas células neoplásicas, enquanto GLUT-1 e CD44 foram negativas. Estes achados sugerem que a expressão de FASN e a perda de CD44 podem estar envolvidas na patogênese do linfoma de células NK/T nasal extranodal, e que GLUT-1 não deve participar da adaptação das células tumorais ao ambiente de hipóxia. Estudos adicionais com séries maiores são necessários para confirmar nossos resultados iniciais.

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A complete series of cross-sectional computed tomography (CT) scans were obtained of a mummy of an Egyptian priestess, Tjenmutengebtiu, (Jeni), who lived in the twenty-second Dynasty (c. 945-715 BC). The purpose of this joint British Museum and St. Thomas’ Hospital project was effectively to ‘unwrap’ a mummy using cross-sectional X-rays. Jeni is encased in a beautifully decorated anthropomorphic cartonnage coffin. The head and neck were scanned with 2mm slices, the teeth with 1mm slices and the rest of the body with 4 mm slices, a 512 x 512 matrix was used. The 2D CT images, and 3D surface reconstruction’s, demonstrate many features of the embalming techniques and funerary customs of the XXII Dynasty. The presence of cloth protruding from the nasal cavities into the otherwise empty cranial cavity indicates that the brain was extracted via the nose. The remains of the heart can be seen as well as four organ packs corresponding to the mummified and repackaged lungs, intestines, stomach and liver. Each of the organ packs encloses a wax figurine representing one of the four sons of Horus. The teeth are in very good condition with little signs of wear, which, considering the gritty diet of the Egyptians, indicates that Jeni must have been very young when she died. A young age of death is also suggested by analysis of the shape of the molar teeth. The body is generally in very good condition demonstrating the consummate skill of the twenty-second Dynasty embalmers.

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Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections are emerging in southeast Queensland, Australia, but the incidence of carriage of CA-MRSA strains is unknown. The aim of this study was to assess the nasal carriage rate of S. aureus, including CA-MRSA strains, in the general adult population of southeast Queensland. 396 patients presenting to general practices in two Brisbane suburbs and 303 volunteers randomly selected from the electoral rolls in the same suburbs completed a medical questionnaire and had nasal swabs performed for S. aureus. All isolates of S. aureus underwent antibiotic susceptibility testing and single-nucleotide polymorphism (SNP) and binary typing, including determination of Panton–Valentine leukocidin (PVL). The nasal carriage rate of methicillin-susceptible S. aureus (MSSA) was 202/699 (28%), a rate similar to that found in other community-based nasal carriage studies. According to multivariate analysis, nasal carriage of S. aureus was associated with male sex, young adult age group and Caucasian ethnicity. Only two study isolates (one MSSA and one CA-MRSA) carried PVL. The nasal carriage rate of MRSA was low, at 5/699 (0.7%), and only two study participants (0.3%) had CA-MRSA strains. CA-MRSA is an emerging cause of infection in southeast Queensland, but as yet the incidence of carriage of CA-MRSA in the general community is low.

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Unsteady natural convection inside a triangular cavity subject to a non-instantaneous heating on the inclined walls in the form of an imposed temperature which increases linearly up to a prescribed steady value over a prescribed time is reported. The development of the flow from start-up to a steady-state has been described based on scaling analyses and direct numerical simulations. The ramp temperature has been chosen in such a way that the boundary layer is reached a quasi-steady mode before the growth of the temperature is completed. In this mode the thermal boundary layer at first grows in thickness, then contracts with increasing time. However, if the imposed wall temperature growth period is sufficiently short, the boundary layer develops differently. It is seen that the shape of many houses are isosceles triangular cross-section. The heat transfer process through the roof of the attic-shaped space should be well understood. Because, in the building energy, one of the most important objectives for design and construction of houses is to provide thermal comfort for occupants. Moreover, in the present energy-conscious society it is also a requirement for houses to be energy efficient, i.e. the energy consumption for heating or air-conditioning houses must be minimized.

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Spatially resolved cathodoluminescence (CL) study of a ZnO nanonail, having thin shank, tapered neck, and hexagonal head sections, is reported. Monochromatic imaging and line scan profiling indicate that the wave guiding and leaking from growth imperfections in addition to the oxygen deficiency variation determine the spatial contrast of CL emissions. Occurrence of resonance peaks at identical wavelengths regardless of CL-excitation spots is inconsistent with the whispering-gallery mode (WGM) resonances of a two-dimensional cavity in the finite difference time domain simulation. However, three dimensioanl cavity simulation produced WGM peaks that are consistent with the experimental spectra, including transverse-electric resonances that are comparable to transverse-magnetic ones.

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The hexagonal resonator characteristics of an individual ZnO-nanonail’s head were investigated via spatially resolved cathodoluminescence (CL) at room temperature. The positions of most of distinct CL peaks in visible range were well matched to those of whispering gallery modes (WGMs) of a hexagonal dielectric cavity when we took birefringence and dispersion of refractive indices into account. The broad and weak peaks for TE polarization in long wavelength range were consistent with refractive-index values below the threshold for total internal inflection. CL peaks that were not matched to WGMs were identified as either triangular quasi-WGM or Fabry–Pérot resonance modes.