979 resultados para Cochlea - anatomy
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Resumo: A hiperplasia benigna da prstata (HBP) tem elevada prevalncia nos homens entre os 50 e 79 anos de idade, sendo ubiquitria com o envelhecimento. Devido significativa morbi-mortalidade associada aos tratamentos mdicos e cirrgicos currentemente disponveis, so necessrias novas tecnologias para melhorar os resultados e minimizar o desconforto dos doentes. Recentemente, estudos preliminares de experimentao animal e em 3 doentes tratados, sugeriram a embolizao arterial prosttica selectiva (EAPS) como hiptese teraputica para a HBP. Decidimos investigar se a EAPS poderia ser um procedimento bem sucedido no tratamento da HBP gravemente sintomtica. Para tal realizmos um estudo antomo-radiolgico e clnico em 63 doentes com recurso a uma teraputica inovadora minimamente invasiva guiada pela imagem. Avalimos 126 hemiplvis com recurso a Angio-RM, Angio-TC e Angiografia Digital de Subtraco, com o intuito de definir os padres bsicos de bifurcao das artrias ilacas internas at agora apenas descritos em estudos cadavricos. Estudmos ainda o suprimento vascular arterial prosttico, identificando: 1 as artrias prostticas; 2 origem e direco; 3 os ramos intra-prostticos; 4 anastomoses com outras artrias. Em relao aos resultados anatmicos, identificmos 181 artrias prostticas, j que em 43.7% das hemiplvis existiam dois pedculos arteriais prostticos com origens independentes. A origem mais frequente foi a artria pudenda interna (39.7%), seguida do tronco comum glteo-pudendo (21%) e da artria vesical superior (18.2%). Origens menos frequentes foram a artria obturadora (12.1%), as artrias glteas inferior (3.9%)ou superior (1.7%), ramos rectais provenientes da artria mesentrica inferior (1.7%) e a artria pudenda acessria (1.7%). Identificaram-se anastomoses com as artrias adjacentes em 57.9% dos casos: com a terminao da artria pudenda interna (41.6%),artrias prostticas contra-laterais (18.2%) e homo-laterais (11.7%), com ramos rectais (15.6%) e com artrias vesicais (12.9%). Em relao ao estudo clnico tratmos 63 doentes (idades compreendidas entre 52 - 82 anos, mdia 69.5 anos) com HBP gravemente sintomtica refractria teraputica mdica h mais de 6 meses. Foi possvel avaliao aps o tratamento em 37 doentes: mdia de seguimento de 4.7 meses (variando entre 1 e 12 meses). A EAPS unilateral foi possvel em todos os doentes, com embolizao bilateral em 73% dos casos. A embolizao bilateral no foi possvel em 27% dos casos devido a tortuosidade, alteraes ateroesclerticas e pequeno calibre das artrias ilacas e/ou prostticas. Em mdia houve uma melhoria do International Prostate Symptom Score (IPSS) de 10.8 pontos, da QoL de 1.5 pontos e do Internationl Index of Erectile Function (IIEF) de 2.1 pontos. Houve uma reduo mdia do PSA de 30% (2.4 ng/mL), um aumento do pico de fluxo urinrio (Qmax) de 3.1 - 3.85 mL/s e uma reduo mdia do volume prosttico de 21% (18.5 mL). Registou-se uma complicao major: pequena rea de isqumia da parede vesical tratada cirurgicamente. Em 75% dos doentes tratados obteve-se sucesso clnico com franca melhoria dos sintomas, enquanto 25% dos doentes foram considerados insucesso clnico por se ter registado uma fraca ou ausente melhoria sintomtica aps a embolizao. Os restantes doentes tratados esto sob controlo evolutivo, pararam toda a medicao prosttica, sem qualquer caso de disfuno sexual associada com o tratamento. Este trabalho constitui o primeiro estudo anatmico descritivo in vivo das artrias prostticas, conseguido devido utilizao de tcnicas de imagem nunca usadas para este fim. O uso clnico dos dados anatmicos acima referidos permitiu a implementao de tcnicas de Radiologia de Interveno no tratatamento de uma doena de elevada prevalncia. ------------------------------- ABSTRACT: Benign prostatic hyperplasia (BPH) has high prevalence in men aged 5079 years being ubiquitous with aging. Due to significant morbi-mortality associated with currently available medical and surgical treatments, there is the need for innovative technologies to continue to improve outcomes and minimize patient discomfort and morbidity. Recently, prostatic arterial embolization (PAE) was suggested as a treatmentoption for BPH based on preliminary results from animal studies and 3 treated patients. We decided to investigate if PAE might be a successful treatment option for severely symptomatic BPH patients. We performed a clinical and anatomical-radiological study in 63 patients with the use of an inovative image-guided minimally invasive technique. We evaluated 126 pelvic sides using Angio-MR or Angio-CT and Catheter Angiography before embolisation to treat symptomatic BPH. We aimed to define the main branching patterns of the male internal iliac arteries, so far only studied in the cadaver. We also evaluated the prostatic arterial supply, identifying: 1 the prostatic arteries; 2 origin and direction; 3 intra-prostatic branches; 4 anastomoses with surrounding arteries. Regarding the anatomical study we identified 181 prostatic arteries, because in 43.7% of pelvic sides 2 separate prostatic vascular pedicles were found. The most frequent origin was the internal pudendal artery (39.7%) with the common glutealpudendal trunk (21%) and superior vesical arteries (18.2%) the next commonest. Less frequent origins were the obturator artery (12.1%), the inferior (3.9%) or superior (1.7%) gluteal arteries, rectal branches from the inferior mesenteric artery (1.7%) and the accessory pudendal artery (1.7%). There were anastomoses with the surrounding arteries in 57.9% of cases: termination of the internal pudendal artery (41.6%), contralateral prostatic arteries (18.2%), same-side prostatic arteries (11.7%), rectal branches (15.6%), and vesical arteries (12.9%).Regarding the clinical study, we treated 63 patients aged 5282 years (mean 69.5 years) who presented with symptomatic BPH refractory to medical treatment for at least 6 months. Follow-up evaluation (mean 4.7 months, range 1-12 months) was possible in 37 patients. PAE was achieved in all patients with bilateral embolization in 73%. In 27% PAE was performed unilaterally due to tortuosity, atherosclerotic changes and small size of iliac and prostatic arteries. There was a mean decrease in the IPSS of 10.8 points, a mean improvement in QoL of 1.5 points, and a mean increase in the sexual function score of 2.1 points. There was a mean PSA reduction of 30% (2.4 ng/mL), a Qmax increase of 3.1 to 3.85 mL/sec, and a mean prostate volume decrease of 21% (18.5 mL). There was one major complication: a small area of bladder wall ischemia treated by surgery. Overall, 75% of patients were considered clinical success with major improvement after PAE, while 25% of patients were considered clinical failure with little or no improvement after PAE. All remaining patients are under follow-up, stopped all prostatic medication, and reported no sexual dysfunction. This study is the first one to describe the radiological anatomy of the prostatic arteries, with the use of imaging techniques never used for this purpose before. The clinical use of the anatomical findings allowed the implementation of Interventional Radiology tehniques in the treatment of a disease with a high prevalence.
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Nesta dissertao apresentado um estudo dos sistemas de processamento automtico de imagem em contexto de um problema relacionado com a individualizao de neurnios em imagens da nematoda C. elegans durante estudos relacionados com a doena de Parkinson. Apresenta-se uma breve introduo anatomia do verme, uma introduo doena de Parkinson e uso do C. elegans em estudos relacionados e tambm feita a anlise de artigos em contexto de processamento de imagem para contextualizar a situao atual de solues para o problema de extrao de caractersticas e regies especficas. Neste projeto desenvolvida uma pipeline com o auxilio do software CellProfiler para procurar uma resposta para o problema em questo.
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BACKGROUND: Mesenchymal stem/stromal cells have unique properties favorable to their use in clinical practice and have been studied for cardiac repair. However, these cells are larger than coronary microvessels and there is controversy about the risk of embolization and microinfarctions, which could jeopardize the safety and efficacy of intracoronary route for their delivery. The index of microcirculatory resistance (IMR) is an invasive method for quantitatively assessing the coronary microcirculation status. OBJECTIVES: To examine heart microcirculation after intracoronary injection of mesenchymal stem/stromal cells with the index of microcirculatory resistance. METHODS: Healthy swine were randomized to receive by intracoronary route either 30x106 MSC or the same solution with no cells (1% human albumin/PBS) (placebo). Blinded operators took coronary pressure and flow measurements, prior to intracoronary infusion and at 5 and 30 minutes post-delivery. Coronary flow reserve (CFR) and the IMR were compared between groups. RESULTS: CFR and IMR were done with a variance within the 3 transit time measurements of 6% at rest and 11% at maximal hyperemia. After intracoronary infusion there were no significant differences in CFR. The IMR was significantly higher in MSC-injected animals (at 30 minutes, 14.2U vs. 8.8U, p = 0.02) and intragroup analysis showed a significant increase of 112% from baseline to 30 minutes after cell infusion, although no electrocardiographic changes or clinical deterioration were noted. CONCLUSION: Overall, this study provides definitive evidence of microcirculatory disruption upon intracoronary administration of mesenchymal stem/stromal cells, in a large animal model closely resembling human cardiac physiology, function and anatomy.
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Considering Alan Turings challenge in Computing Machinery and Intelligence (1950) can machines play the imitation game? it is proposed that the requirements of the Turing test are already implicitly being used for checking the credibility of virtual characters and avatars. Like characters, Avatars aim to visually express emotions (the exterior signs of the existence of feeling) and its creators have to resort to emotion codes. Traditional arts have profusely contributed for this field and, together with the science of anatomy, shaped the grounds for current Facial Action Coding System (FACS) and their databases. However, FACS researchers have to improve their instruction tables so that the machines will be able, in a near future, to be programmed to carry out the operation of recognizing human expressions (face and body) and classify them adequately. For the moment, the reproductions have to resort to the copy of real life expressions, and the presente smile of avatars comes from mirroring their human users.
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The Gallus gallus (chicken) embryo is a central model organism in evolutionary developmental biology. Its anatomy and developmental genetics have been extensively studied and many relevant evolutionary implications have been made so far. However, important questions regarding the developmental origin of the chicken skull bones are still unresolved such that no solid homology can be established across organisms. This precludes evolutionary comparisons between this and other avian model systems in which skull anatomy has evolved significantly over the last millions of years.(...)
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RESUMO: Os mais recentes mtodos de neuro imagem tal como a Ressonncia Magntica (RM) permitiram obter imagens detalhadas do crebro humano in vivo. Essas imagens revelam, muitas vezes, achados imprevistos face ao padro normal, com elevada propenso para os indivduos idosos e franca coexistncia com fatores de risco vascular, como caracterstica dum processo de envelhecimento normal. Embora na ltima dcada tenham surgido vrias publicaes sobre este assunto, ele continua ainda pouco explicado. Um pouco por todo o mundo tm emergido os programas de preveno da doena e promoo da sade desenvolvidos pela Sade Pblica suportadas sobretudo pelo avano das tecnologias mdicas que resultaram, entre outros impactos, num crescimento da populao idosa. Estima-se, em 2030, uma composio demogrfica com 20% de indivduos acima dos 65 anos. Neste contexto, a doena microvascular cerebral a causa mais frequente de comprometimento cognitivo vascular no idoso sendo as caractersticas senescentes na imagem por RM do tipo leses isqumicas da Substncia Branca (Leukoaraiosis) e enfartes lacunares (Status lacunar), atrofia cerebral, gliose e acumulao excessiva de ferro nos ncleos da base. Esta tese, considerando a linha de investigao de que deriva Cincias da Vida - especializao em Medicina Clinica - Biotecnologia, rene e reflete sobre trs vertentes ligadas RM e interdependentes em relao a uma problemtica comum. A primeira trata da caracterizao da Tecnologia por Ressonncia Magntica existente em Portugal, a qual inclui uma avaliao exploratria da aplicao da tcnica de Difuso Anisotrpica nos estudos cerebrais. As dimenses analticas estudadas foram a Tecnolgica, Sociodemogrfica e Econmica. Na recolha de dados recorreu-se a vrias fontes de informao e a uma metodologia exploratria faseada, validada pela triangulao dos resultados. A sua anlise obedeceu a critrios de estratificao e agrupamento segundo as mesmas dimenses analticas. Otimizao da anisotropia fronto-calosa e [RM 1,5T] no idoso normal e com risco crebro-vascular A segunda descreve o estudo antomo radiolgico que recaiu sobre parmetros de quantificao assente na temtica do crebro do idoso em cadver segundo uma metodologia experimental aplicada s mtricas da difuso por RM. Na terceira, e ltima, apresentado o estudo tcnico - radiolgico para avaliao e otimizao da imagem ponderada em difuso em estudos clnicos associados ao crebro do idoso The Usual Brain Aging ou Envelhecimento Cerebral Normal, com base metodolgica assente nos critrios e indicadores estabelecidos pelo Estudo de Imagem de Roterdo (Rotterdam Scan Study - RSS). Como principais resultados obteve-se que no existem em Portugal estruturas para avaliao dos equipamentos pesados ou Agncia de Avaliao das Tecnologias da Sade para desenvolver o importante papel da produo de estudos comparativos entre os equipamentos disponveis no mercado, a relao preo-qualidade e a sua afetao s necessidades clnico-epidemiolgicas. Constatou-se que a implementao de equipamentos de RM est fortemente assente em critrios econmicos carecendo de recomendaes e diretivas para o uso racionalizado destas tecnologias. Quanto a dados quantitativos conclumos que a maioria dos equipamentos est instalada em instituies privadas (80,2%); a intensidade de campo magntico mais frequente [1,5T] com 119 equipamentos; os equipamentos esto instalados maioritariamente nos distritos de Lisboa (55 unidades) e do Porto (39 unidades); o rcio mdio de equipamentos por habitante em Portugal de 1 para 65 195 habitantes; a amplitude de gradientes com maior expresso na amostra 30-39mT/m; a maioria dos equipamentos foi instalada no intervalo temporal [2009-2012] com 59 equipamentos; apenas 6 instituies desenvolvem investigao clinica e a maioria das bobinas para estudos de crnio so do tipo Array. O estudo de otimizao da tcnica da difuso revelou, quanto avaliao dos valoresb, que os mais baixos (b=500 s/mm2 e b=1000 s/mm2), apresentam maior IS e SNR sendo esta uma boa medida referente qualidade de imagem, no entanto, os valores-b mais elevados (b=2000 s/mm2) apresentam maior CNR e CR, face aos anteriores, o Otimizao da anisotropia fronto-calosa e [RM 1,5T] no idoso normal e com risco crebro-vascular que apesar de proporcionar inferior detalhe anatmico e consequentemente inferior qualidade de imagem, num encfalo normal, pode auxiliar na interpretao e apresentar vantagens na identificao de leses microvasculares sempre que persistirem dvidas em relao ao diagnstico diferencial de doena microvascular do tipo status lacunar ou Hiperintensidades da Substncia Branca. As alteraes deste parmetro so particularmente refletidas nas diferenas da avaliao da qualidade de imagem na regio fronto-calos Conclumos da avaliao quantitativa da concentrao mdia de ferro (26Fe) em todas as faixas etrias que os ncleos da base que apresentam maior concentrao so, por ordem decrescente: Substncia Nigra, Globus Pallidus, Putamen, Tlamo, Ncleo Rubro e Ncleo Caudado; que existe uma predominncia na concentrao de ferro (26Fe) no hemisfrio esquerdo e que os indivduos do gnero masculino apresentam mais ferro (26Fe) que os do gnero feminino nas faixas etrias [30-40[, [40-50[ e [50-60[. Como principal concluso do estudo da concentrao mdia de ferro em relao idade destacamos que a concentrao mdia de ferro (26Fe) superior nos grupos etrios superiores, logo aumenta com a idade, sobretudo na Substncia Nigra e no Ncleo Lenticular. No estudo tcnico-radiolgico encontrmos evidncias do aumento da difusibilidade da gua na substncia branca subcortical dos sujeitos idosos comparativamente aos mais jovens. Uma relao idntica foi avaliada nos tlamos. O aumento relacionado com a idade parece ser predominantemente observado em doentes com mais de 65 anos de idade o que pode refletir alteraes estruturais ligeiras associados ao envelhecimento normal. Os resultados indicam que a anlise quantitativa das imagens ponderadas em difuso fornece informaes, sobre a estrutura do crebro, as quai s no esto disponveis apenas por inspeo visual, tanto nas imagens ponderadas em difuso como em outras sequncias de aplicao clnica de rotina. Para fazer face s desvantagens dos sistemas de quantificao das HSB os quais so dispendiosos, complexos, requererem tecnologia e formao especficas, recomendamos que a aplicao automatizada GUIAL, desenvolvida ao longo do nosso trabalho de utilizao elementar e prtica para que seja introduzida nos sistemas de aquisio de imagem por RM com o fim de integrar o processamento de imagem nos indivduos portadores de fatores de risco vascular. A avaliao do ADC, nesta amostra, permitiu concluir que a variao desta varivel explicada estatisticamente pela existncia da condio clnica de status lacunar em ambos os hemisfrios ou por outras palavras, o status lacunar influencia o valor de ADC. Embora uma pequena percentagem da variao do ADC seja explicada pelo gnero, o ADC nos homens foi superior ao das mulheres o que no nos surpreende, pois so tambm os homens onde a frequncia de doena microvascular se revelou mais expressiva. Os valores do ADC, globalmente, entre os hemisfrios cerebrais no mostraram alteraes exceto na SB entre os idosos e no idosos. A SB da regio frontal mostrou valores diminudos na anisotropia e isotropia face s restantes reas anatmicas. Os estudos indicam que na idade avanada existe uma maior predisposio para suscetibilidades de estrutura com status de desconexo. A classificao das HSB foi superior em indivduos mais velhos e com status lacunar, e em menor quantidade (inferior rating de classificao) nos indivduos idosos sem status lacunar. As alteraes volumtricas foram mais frequentes no homem do que na mulher, presumivelmente devido associao com a elevada classificao de status lacunar. Um aumento do ndice de Evan correspondeu, neste estudo, ao aumento das HSB, diminuio do volume cerebral total, expanso ventrculo-sulcal frontal e ao aumento da medida do ngulo caloso. Estes resultados foram agravados pela classificao elevada de status lacunar nos indivduos que apresentaram indcios de doena de pequenos vasos, com manifesto aumento dos espaos de Virchow-Robin,enfartes lacunares ou HSB. Esses resultados foram mais expressivos no gnero masculino do que no feminino revelando uma maior vulnerabilidade sobretudo na atrofia frontal nos homens. Por sua vez as dimenses do Corpo Caloso tornaram-se reduzidas devido compresso dos ventrculos laterais e terceiro ventrculo. Estes indicadores tiveram expresso particularmente nos indivduos com mais de 65 anos. ---------------------------------------------------------------------------------------------ABSTRACT: The latest neuroimaging methods, such as Magnetic Resonance Imaging (MRI), have enabled detailed images of in vivo human brain. These images reveal often unexpected findings related to the normal pattern, with high predisposition for the elderly people with forthright coexistence with vascular risk factors such as characteristics of a normal aging process. Although it has been, in the last decade, several publications on this subject, it is still little explained. All over the world have emerged disease prevention programs and health promotion developed by the Public Health sector, supported mainly by the advancement of medical technologies that have resulted, among other impacts, in a growing of the elderly population. It is estimated, in 2030, a demographic composition with 20% o people over 65 years. In this context, microvascular disease is the most common cause of cognitive vascular impairment in the elderly and senescent characteristics in the MRI trough ischemic lesions of the white matter (Leukoaraiosis) and lacunar infarcts (lacunar status), cerebral atrophy, gliosis and iron accumulation in the basal ganglia in excess.This thesis, considering the research line that stems - Life Sciences - specialization in Clinical Medicine, Biotechnology, gathers and reflects on three aspects linked to MR, interdependent and related to a common problem. The first deals with the Magnetic Resonance Technology characterization in Portugal, which includes an exploratory evaluation of the implementation of Anisotropic Diffusion technique in brain studies. The analytical dimensions studied were the Technologic, Socio-demographic and Economics. Collecting data was supported by different sources of information and was applied an exploratory methodology whose results were validated by triangulation. The research method was grouped and stratified criteria under the same analytical dimensions. The second describes the anatomical study - which was focused on radiological measurement parameters, based on the brains specimen under an experimental methodology applied to MRI diffusion metrics. Radiological evaluation and optimization of the weighted image diffusion in clinical studies were associated with the brain of the elderly "The Usual Brain Aging" with methodological basis based on established criteria and indicators by Rotterdam Scan Study (RSS). The main results obtained reveal the inexistence frameworks in Portugal for evaluation of equipments or Agency of Health Technology to produce studies comparing the equipment available on the market, the value for money and its allocation to clinical and epidemiological needs. It was found that the implementation of MRI equipment is strongly based on economic criteria lacking recommendations and guidelines for the rationalized use of these technologies. As the quantitative data we conclude that most of the scanners are located in private clinical institutions (80,2%); the most frequent magnetic field intensity is [1.5T] with 119 scanners; the scanners are mainly installed in Lisbon (55 units) and Porto (39 units) districts; the average ratio of equipment per capita in Portugal is 1 to 65 195 people; the gradient power with higher expression in the sample is 30-39mT / m;most of the scanners were installed in the years range [2009-2012 years] with 59 equipment; only 6 clinical placements develop clinical research and the most coils for brain studies are of Array type. The optimization study of diffusion technique revealed, as the assessment of the bvalues, the lower (b = 500 s / mm2 and b = 1000 s / mm 2), promotes an increase in the SI and SNR being this measure related to a higher image quality, however the highest b values (b = 2000 s / mm 2) have a higher CNR (Contrast to Noise-Ratio) and CR (Contrast Ratio), compared to the previous ones. This may provide less anatomical details and, thus, ower image quality, of a normal brain, however can help the interpretation and have advantages in identifying microvascular injuries when doubts persist regarding the differential diagnosis of microvascular disease of lacunar or WMH (White Matter Hyperintensities) status type. Changes on this parameter are Otimizao da anisotropia fronto-calosa e [RM 1,5T] no idoso normal e com risco crebro-vascular particularly reflected in the differences of image quality evaluation in the frontocallosum anatomical area. We conclude from the quantitative assessment of the average concentration of iron (26Fe), in all age groups to the basal ganglia, that the higher concentrations are, in descending order: Nigral Substantia, Globus pallidus, Putamen, Thalamus, Rubio nucleus and Caudate nucleus; that there is a predominance in the concentration of iron (26Fe) in the left hemisphere and that male gender show higher iron (26Fe) level tha females, in the age groups [30-40 [[40-50 [and [50- 60 [. Regarding a main conclusion of the mean concentration study of iron, in terms of age we point out that the average concentration of iron (26Fe) is higher among older groups and increases with age, especially in Nigral Substantia and Lenticular Nucleus. On the technical and radiological study we found evidence of an increased in water /diffusivity in the ubcortical white matter of the elderly compared with younger subjects. A similar relationship was assessed in the Thalamus. The increase agerelated seems to be predominantly observed in patients over 65 years which may reflect minor structural changes associated with normal aging. The results indicate that quantitative analysis of diffusion weighted imaging can provide information about the structure of the brain which is not reached only by visual inspection or standard sequences applied in clinical routine. To address the disadvantages the systems of quantification of WMH which the authors state that are costly, complex, require specific technology and training, we recommend that the automated application GUIAL, developed over our work is basic and practical to use and to be introduced in MR image systems acquisition in order to integrate image processing in patients with vascular risk factors. The evaluation of the ADC showed that its variation is statistically explained by the existence of the medical condition of lacunar status, in both hemispheres, or in other words, the lacunar status influences the ADC value. Although a small percentage of the ADC variation is explained by gender, the ADC in men was higher than women which Otimizao da anisotropia fronto-calosa e [RM 1,5T] no idoso normal e com risco crebro-vascular do not surprise us, since they are also men where the frequency of microvasculardisease has proved more significant. The values of ADC, overall, between the cerebral hemispheres showed no changes but were different in WM among the elderly and non-elderly subjects.The WM's forehead showed decreased values in anisotropy and isotropy face the other anatomical areas. The studies indicate that in old age there is a greater tendency to higher susceptibility to disconnection- status framework. The classification of WMH was higher in elderly people and lacunar status, and fewer (lower classification rating) in the elderly without lacunar status. volumetric changes were more frequent in men than in women, most probably because of its association with high lacunar status rating. An increase of Evan index corresponded, in this study, to an increase in WMH, to a decreased of total brain volume, to a ventricle sulcal frontal and callous angle expansion. These results were wound up by high ranking of lacunar status in subjects who had small vessel disease, clear increase in spaces of Virchow-Robin, lacunar infarctions or WMH. These results were more significant in males than in females revealing vulnerability particularly in the frontal atrophy in men. In turn the size of Corpus Callosum because reduced due to the compression of the lateral and third ventricles. These indicators had expression particularly in individuals over 65 years.
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Resection of midline skull base lesions involve approaches needing extensive neurovascular manipulation. Transnasal endoscopic approach (TEA) is minimally invasive and ideal for certain selected lesions of the anterior skull base. A thorough knowledge of endonasal endoscopic anatomy is essential to be well versed with its surgical applications and this is possible only by dedicated cadaveric dissections. The goal in this study was to understand endoscopic anatomy of the orbital apex, petrous apex and the pterygopalatine fossa. Six cadaveric heads (3 injected and 3 non injected) and 12 sides, were dissected using a TEA outlining systematically, the steps of surgical dissection and the landmarks encountered. Dissection done by the "2 nostril, 4 hands" technique, allows better transnasal instrumentation with two surgeons working in unison with each other. The main surgical landmarks for the orbital apex are the carotid artery protuberance in the lateral sphenoid wall, optic nerve canal, lateral optico-carotid recess, optic strut and the V2 nerve. Orbital apex includes structures passing through the superior and inferior orbital fissure and the optic nerve canal. Vidian nerve canal and the V2 are important landmarks for the petrous apex. Identification of the sphenopalatine artery, V2 and foramen rotundum are important during dissection of the pterygopalatine fossa. In conclusion, the major potential advantage of TEA to the skull base is that it provides a direct anatomical route to the lesion without traversing any major neurovascular structures, as against the open transcranial approaches which involve more neurovascular manipulation and brain retraction. Obviously, these approaches require close cooperation and collaboration between otorhinolaryngologists and neurosurgeons.
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The straightforward anatomical organisation of the developing and mature rat spinal cord was used to determine and interpret the time of appearance and expression patterns of microtubule-associated proteins (MAP) 1b and 2. Immunoblots revealed the presence of MAP1b and 2 in the early embryonic rat spinal cord and confirmed the specificity of the used anti-MAP mouse monoclonal antibodies. The immunocytochemical data demonstrated a rostral-to-caudal and ventral-to-dorsal gradient in the expression of MAP1b/2 within the developing spinal cord. In the matrix layer, MAP1b was found in a distinct radial pattern distributed between the membrana limitans interna and externa between embryonal day (E)12 and E15. Immunostaining for vimentin revealed that this MAP1b pattern was morphologically and topographically different from the radial glial pattern which was present in the matrix layer between E13 and E19. The ventral-to-dorsal developmental gradient of the MAP1b staining in the spinal cord matrix layer indicates a close involvement of MAP1b either in the organisation of the microtubules in the cytoplasmatic extensions of the proliferating neuroblasts or neuroblast mitosis. MAP2 could not be detected in the developing matrix layer. In the mantle and marginal layer, MAP1b was abundantly present between E12 and postnatal day (P)0. After birth, the staining intensity for MAP1b gradually decreased in both layers towards a faint appearance at maturity. The distribution patterns suggest an involvement of MAP1b in the maturation of the motor neurons, the contralaterally and ipsilaterally projecting axons and the ascending and descending long axons of the rat spinal cord. MAP2 was present in the spinal cord grey matter between E12 and maturity, which reflects a role for MAP2 in the development as well as in the maintenance of microtubules. The present description of the expression patterns of MAP1b and 2 in the developing spinal cord suggests important roles of the two proteins in various morphogenetic events. The findings may serve as the basis for future studies on the function of MAP1b and 2 in the development of the central nervous system.
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Background The distally based anterolateral thigh (ALT) flap is an interesting reconstructive solution for complex soft tissue defects of the knee. In spite of a low donor site morbidity and wide covering surface as well as arch of rotation, it has never gained popularity among reconstructive surgeons. Venous congestion and difficult flap dissection in the presence of a variable anatomy of the vascular pedicle are the possible reasons.Methods An anatomical study of 15 cadaver legs was performed to further clarify the blood supply of the distally based ALT. Our early experience with the use of preoperative angiography and a safe flap design modification that avoids distal intramuscular skeletonization of the vascular pedicle and includes a subcutaneous strip ranging from the distal end of the flap to the pivot point is presented.Results The distally based ALT presents a constant and reliable retrograde vascular contribution from the superior genicular artery. Preoperative angiography reliably identified and avoided critical Shieh Type II pedicled flaps. The preservation of a subcutaneous strip ranging from the distal flap end to the upper knee was associated with the absence of venous congestion in a short case series.Conclusions Preoperative angiography and a flap design modification are proposed to allow the safe transfer of the distally based ALT to reconstruct soft tissue defects of the knee.
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OBJECTIVES: To investigate the development of the ureterovesical junction in rats. METHODS: A total of 110 albino rats (50 prenatal and 60 newborn) with a gestation of 21 days were studied at the age of 17 days after conception until 5 days after birth. The lower urinary tract was microdissected. Microphotography (110 animals), histologic examination (44 animals), and scanning electron microscopy (66 animals) of the ureterovesical junction were performed. Urea and creatinine from the amniotic fluid of 20 fetuses and from the urine of 10 neonates were measured. RESULTS: At day 17 after conception, separate penetration of the mesonephric duct and ureter into the wall of the urogenital sinus was observed. Continuity between the lumen of the ureter and the urogenital sinus was established on day 19 after conception. The straight passage of the intramural ureter into the urogenital sinus at day 17 after conception changed to the definitive L-shape with a vertical entry into the bladder on day 5 after birth. In the distal ureter, the change of the mesenchymal tissue into immature smooth muscle was first observed at birth, and the muscle became mature on the fifth postnatal day. At birth, Waldeyer's sheath was recognized. The creatinine and urea levels were stable prenatally (average 22.4 micromol/L and 6.88 mmol/L, respectively) and rose significantly postnatally (average 133 micromol/L and 32.65 mmol/L, respectively). CONCLUSIONS: The attachment of the ureter to the urogenital sinus and later to the bladder, the modification of its passage, and its mobility within Waldeyer's sheath may be essential in preventing vesicoureteral reflux. The production of urine and its flow does not seem to be the trigger of ureteral smooth muscle formation.
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Anatomical structures and mechanisms linking genes to neuropsychiatric disorders are not deciphered. Reciprocal copy number variants at the 16p11.2 BP4-BP5 locus offer a unique opportunity to study the intermediate phenotypes in carriers at high risk for autism spectrum disorder (ASD) or schizophrenia (SZ). We investigated the variation in brain anatomy in 16p11.2 deletion and duplication carriers. Beyond gene dosage effects on global brain metrics, we show that the number of genomic copies negatively correlated to the gray matter volume and white matter tissue properties in cortico-subcortical regions implicated in reward, language and social cognition. Despite the near absence of ASD or SZ diagnoses in our 16p11.2 cohort, the pattern of brain anatomy changes in carriers spatially overlaps with the well-established structural abnormalities in ASD and SZ. Using measures of peripheral mRNA levels, we confirm our genomic copy number findings. This combined molecular, neuroimaging and clinical approach, applied to larger datasets, will help interpret the relative contributions of genes to neuropsychiatric conditions by measuring their effect on local brain anatomy.Molecular Psychiatry advance online publication, 25 November 2014; doi:10.1038/mp.2014.145.
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OBJECTIVE: Contemporary free-breathing non contrast enhanced cardiovascular magnetic resonance angiography (CMRA) was qualitatively and quantitatively evaluated to ascertain the reproducibility of the method for coronary artery luminal dimension measurements. SUBJECTS AND METHODS: Twenty-two healthy volunteers (mean age 32 +/- 7 years, 12 males) without coronary artery disease were imaged at 2 centers (1 each in Europe and North America) using navigator-gated and corrected SSFP CMRA on a commercial whole body 1.5T System. Repeat images of right (RCA, n = 21), left anterior descending (LAD, n = 14) and left circumflex (LCX, n = 14) coronary arteries were obtained in separate sessions using identical scan protocol and imaging parameters. True visible vessel length, signal-to-noise (SNR), contrast-to-noise ratios (CNR) and the average luminal diameter over the first 4 cm of the vessel were measured. Intra-observer, inter-observer and inter-scan reproducibility of coronary artery luminal diameter were determined using Pearson's correlation, Bland-Altman analysis and intraclass correlation coefficients (ICC). RESULTS: CNR, SNR and the mean length of the RCA, LAD and LCX imaged for original and repeat scans were not significantly different (all p > 0.30). There was a high degree of intra-observer, inter-observer and inter-scan agreements for RCA, LAD and LCX luminal diameter respectively on Bland-Altman and ICC analysis (ICC's for RCA: 0.98. 0.98 and 0.86; LAD: 0.89, 0.89 and 0.63; LCX: 0.95, 0.94 and 0.79). CONCLUSION: In a 2-center study, we demonstrate that free-breathing 3D SSFP CMRA can visualize long continuous segments of coronary vessels with highly reproducible measurements of luminal diameter.
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The determination of characteristic cardiac parameters, such as displacement, stress and strain distribution are essential for an understanding of the mechanics of the heart. The calculation of these parameters has been limited until recently by the use of idealised mathematical representations of biventricular geometries and by applying simple material laws. On the basis of 20 short axis heart slices and in consideration of linear and nonlinear material behaviour we have developed a FE model with about 100,000 degrees of freedom. Marching Cubes and Phong's incremental shading technique were used to visualise the three dimensional geometry. In a quasistatic FE analysis continuous distribution of regional stress and strain corresponding to the endsystolic state were calculated. Substantial regional variation of the Von Mises stress and the total strain energy were observed at all levels of the heart model. The results of both the linear elastic model and the model with a nonlinear material description (Mooney-Rivlin) were compared. While the stress distribution and peak stress values were found to be comparable, the displacement vectors obtained with the nonlinear model were generally higher in comparison with the linear elastic case indicating the need to include nonlinear effects.
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Pleistocene glacial and interglacial periods have moulded the evolutionary history of European cold-adapted organisms. The role of the different mountain massifs has, however, not been accurately investigated in the case of high-altitude insect species. Here, we focus on three closely related species of non-flying leaf beetles of the genus Oreina (Coleoptera, Chrysomelidae), which are often found in sympatry within the mountain ranges of Europe. After showing that the species concept as currently applied does not match barcoding results, we show, based on more than 700 sequences from one nuclear and three mitochondrial genes, the role of biogeography in shaping the phylogenetic hypothesis. Dating the phylogeny using an insect molecular clock, we show that the earliest lineages diverged more than 1 Mya and that the main shift in diversification rate occurred between 0.36 and 0.18 Mya. By using a probabilistic approach on the parsimony-based dispersal/vicariance framework (MP-DIVA) as well as a direct likelihood method of state change optimization, we show that the Alps acted as a cross-roads with multiple events of dispersal to and reinvasion from neighbouring mountains. However, the relative importance of vicariance vs. dispersal events on the process of rapid diversification remains difficult to evaluate because of a bias towards overestimation of vicariance in the DIVA algorithm. Parallels are drawn with recent studies of cold-adapted species, although our study reveals novel patterns in diversity and genetic links between European mountains, and highlights the importance of neglected regions, such as the Jura and the Balkanic range.
