923 resultados para FIBROUS SHEATH
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Numerous pulmonary schistosome egg granulomas were present in mice submitted to partial portal vein ligation (Warren's model). The granulomas were characterized by cellular aggregations formed within alveolar tissue. Main cellular types were macrophages (epithelioid cells), eosinophils, plasma cells and lymphocytes. These cells were supported by scanty fibrous stroma and exhibited close membrane contact points amongst themselves, but without forming specialized adhesion apparatus. When granulomas involved arterial structures, proliferation of cndothelial and smooth muscle cells occurred and fibrosis associated with angiogenesis became more evident. Granulomas formed around mature eggs in the pulmonary alveolar tissue presented approximately the same size and morphology regardless of the time of infection, the latter being 10, 18 and 25 weeks after cercarial exposure. This persistence of morphological appearance suggests that pulmonary granulomas do not undergo immunological modulation, as is the case with the granulomas in the liver and, to a lesser extent, in the intestines. Probably, besides general immunological factors, local (stromal) factors play an important role in schistosomal granuloma modulation.
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RESUMO A Esclerose Múltipla (EM) é uma doença desmielinizante crónica do Sistema Nervoso Central (SNC), provocada, em grande parte, por um ataque imuno-mediado contra diversos elementos da bainha de mielina. Dentro dos alvos antigénicos desta resposta autoimune, vários componentes proteicos e lipídicos da mielina têm vindo a ser identificados ao longo dos anos, entre os quais se destacam a proteína básica de mielina(MBP), glicoproteína ligodendrocitária da mielina (MOG), proteína proteolipídica (PLP) e glicoproteína associada à mielina (MAG). Com o desenvolvimento do modelo animal de Encefalomielite Autoimune Experimental (EAE), diversas terapias antigénio-específicas foram desenhadas, baseadas na modificação benéfica da resposta autoimune contra a mielina, tais como a administração de mielina ou seus componentes, os copolímeros terapêuticos, os ligandos peptídeos alterados e, recentemente, a vacinação com ácido desoxirribonucleico (ADN) codificador de proteínas de mielina, integrado em plasmídeos e purificado para administração parentérica. Neste trabalho, apresentamos os resultados de um extenso conjunto de experiências, subordinadas a dois temas fundamentais: 1) avaliação do potencial terapêutico, e dos mecanismos de acção, da vacinação tolerizadora com ADN codificador de proteínas de mielina (MBP, MOG, PLP, MAG) na EAE, e da associação desta vacinação com a administração de ADN de citocinas Th2, ou de oligonucleótidos imunomoduladores; 2) identificação e caracterização da resposta imune contra um novo componente da mielina com potencial antigénico, a proteína inibidora do recrescimento axonal, Nogo-A. No que respeita à vacinação com ADN, os nossos resultados comprovam a eficácia desta terapêutica antigénio-específica na prevenção e tratamento da EAE. Os seus mecanismos de acção incluem, entre outros, a supressão anérgica da proliferação antigénioespecífica dos linfócitos T anti-mielina (no modo de prevenção da doença), o enviesamento Th2 da resposta imune (quando co-administrada com a vacina de ADN codificadora da citocina IL-4, funcionando como terapia génica local), e a redução da diversificação de epítopos da resposta humoral anti-mielina, avaliada através de myelin spotted arrays. A associação das vacinas de ADN com oligonucleótidos imunomoduladores GpG, desenvolvidos para contrariar as sequências CpG imunoestimuladoras presentes no vector de vacinação, levou à melhoria da sua eficácia terapêutica, devida, provavelmente, ao efeito estimulador preferencial dos oligonucleótidos GpG sobre linfócitos Th2 e sobre células reguladoras NK-T. Com base nestes resultados a vacinação com ADN foi desenvolvida para o tratamento da EM em humanos, com ensaios clínicos a decorrerem neste momento. Em relação à proteína Nogo-A, estudos de estrutura primária e de previsão de antigenicidade identificaram a região Nogo-66 como alvo antigénico potencial para a EAE. Nas estirpes de ratinho SJL/J e C57BL/6, fomos capazes de induzir sinais clínicos e histológicos de EAE após imunização com os epítopos encefalitogénicos Nogo1-22, Nogo23- 44 e Nogo45-66, utilizando protocolos de quebra de tolerância imune. Ao mesmo tempo, identificámos e caracterizámos uma resposta linfocitária T específica contra os antigénios contidos na região Nogo-66, e uma resposta linfocitária B com diversificação intra e intermolecular a vários determinantes presentes noutras proteínas da mielina. A transferência adoptiva de linhas celulares Th2 anti-Nogo45-66, levou à melhoria clínica e histológica da EAE em animais recipientes induzidos com outros antigénios de mielina, após migração destas células para o SNC. Estes dados comprovam a importância da Nogo-66 como antigénio na EAE, e a eficácia de terapias antigénio-específicas nela baseadas. No seu conjunto, os nossos resultados confirmam o potencial terapêutico das vacinas de ADN codificadoras de proteínas de mielina, bem como a importância dos encefalitogénios contidos na proteína Nogo-A para a fisiopatologia da EAE e da EM, com eventual relevância para o desenvolvimento de novas terapias antigénio-específicas. O aperfeiçoamento futuro destas terapias poderá levar, eventualmente, a uma capacidade de manipulação da resposta imune que permita o tratamento eficaz das doenças inflamatórias desmielinizantes, como a Esclerose Múltipla. ABSTRACT Multiple Sclerosis (MS) is a chronic demyelinating disease of the Central Nervous System (CNS), caused, mainly, by an immune-mediated attack against several elements of the myelin sheath. Among the antigenic targets for this autoimmune response, several proteic and lipidic myelin components have been identified throughout the years, of which myelin basic protein (MBP), myelin oligodendrocyte glycoprotein (MOG), proteolipidic protein (PLP), and myelin associated glycoprotein (MAG) are the best characterized. With the development of the animal model for MS, Experimental Autoimmune Encephalomyelitis (EAE), several antigen-specific therapies have been designed, based on beneficial modifications of the autoimmune response against myelin. These have included myelin and myelin component administration, therapeutic copolymers, altered peptide ligands and, more recently, vaccination with myelin-protein encoding deoxyribonucleic acid (DNA), integrated into plasmids and purified for parenteral administration. In this work we present the results of an extensive series of experiments, subordinate to two fundamental areas: 1) evaluating the therapeutic potential, and mechanisms of action, of tolerizing myelin protein (MBP, MOG, PLP, MAG) DNA vaccination in EAE, alone and in association with Th2 cytokine DNA administration, or immunomodulatory oligonucleotides; 2) identifying and characterizing the immuneresponse against a new myelin component with antigenic potential, the axonal regrowth inhibitor Nogo-A. Regarding DNA vaccination, our results prove the efficacy of this antigen-specific therapy for the prevention and treatment of EAE. Its mechanisms of action include, among others, anergic suppression of antigen-specific T-cell proliferation against myelin (in prevention mode), Th2 biasing of the immune response (when co-administered with the IL- 4 codifying DNA vaccine, acting as local gene therapy), and reduction of epitope spreading of the anti-myelin antibody response, assessed by myelin spotted arrays. The combination of myelin DNA vaccination with the administration of GpG immunomodulatory oligonucleotides, designed to counteract immunostimulatory CpG motifs present in the vaccination vector, led to an improvement in therapeutic efficacy, probably due to the preferential stimulatory effect of GpG oligonucleotides on Th2 lymphocytes and on regulatory NK-T cells. Based on these results, tolerizing DNA vaccination is being developed for human use, with ongoing clinical trials. As concerns the Nogo-A protein, based on studies of primary structure and prediction of antigenicity, we identified the Nogo-66 region (responsible for the most of the inhibitory capacity of this protein) as a potential antigenic target for EAE. In the SJL/Jand C57BL/6 mouse strains, we were able to induce clinical and histological signs of EAE,after immunization with the encefalitogenic epitopes Nogo1-22, Nogo23-44 and Nogo45-66,using a tolerance breakdown protocol. Concomitantly, we identified and characterized a specific T cell response against these antigens, together with a B cell response which showed extensive intra and intermolecular epitope spread to several determinants present in other myelin proteins. Adoptive transfer of nti-Nogo45-66 Th2 cell lines resulted in clinical and histological improvement of EAE in recipient animals induced with other myelin antigens, after intraparenchymal CNS migration of anti-Nogo cells. These data confirm the relevance of Nogo-66 as an antigen in EAE, as well as the efficacy of antigenspecific therapies based on the response against this protein.In conclusion, our results substantiate the therapeutic potential of myelin-encoding DNA vaccination, as well as the importance of encefalitogenic epitopes present in the Nogo-A protein for the pathophysiology of EAE and MS, with potential relevance for the creation of new antigen specific-therapies. The future development of these therapies may eventually lead to a degree of manipulation of the immune response that allows the effective treatment of autoimmune, inflammatory, demyelinating diseases, such as Multiple Sclerosis.
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Os autores apresentam um caso de tumor fibroso localizado na pleura, maligno, com dimensões gigantes: 26x14x12 cm e P=1,25 Kg, de um doente de sexo feminino de 56 anos. O tumor ocupava praticamente os 2/3 inferiores do campo pulmonar direito com uma inserção invulgar na pleura parietal diafragmática não pediculado e com características histológicas malignas. O diagnóstico de tumor fibroso localizado na pleura, foi feito no material obtido por punção aspirativa por agulha fina. O estudo imunocitoquímico realizado posteriormente na peça operatória confirmou o diagnóstico feito na citologia aspirativa. A avaliação da malignidade só foi feita no exame histológico da peça operatória, utilizando os critérios histológicos de alta celularidade, pleomorfismo celular, actividade mitótica (mais de quatro mitoses em dez campos de grande ampliação do microscópio), áreas de hemorragia e de necrose.
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Introduction: Anatomical variations of the extensor tendons to the fingers are of great clinical interest, due to the relatively high frequency of tendon injury in clinical practice. Material and methods: During routine dissection of the right upper limb of a 67-year-old female preserved corpse, the extensor indicis proprius (EIP) muscle belly originated 3 independent tendons, each with a separate fascial sheath, forming a triple EIP tendon. There was a larger tendon, which occupied a central position, that represented the usual single EIP tendon. In addition, there were two thinner radial and ulnar accessory EIP tendons. The radial-EIP tendon crossed deep to the extensor digitorum communis (EDC) tendon to the index finger in the distal half of the dorsum of the hand to reach the radial side of the extensor expansion hood of the index finger. Discussion: According to the literature, the frequency of a triple EIP tendon ranges from 0%, to as high as 7%, although most authors do not acknowledge the presence of this variant in their series. This variant of the EIP tendon, in which the radial-EIP terminated laterally to the termination of the tendon of the EDC to the index finger, may be a source of confusion intraoperatively, as the EIP tendon has traditionally been identified on the basis of its ulnar location with respect to the EDC tendon. Conclusion: The possibility of a triple EIP tendon should certainly be born in mind by all surgeons when performing tendon repairs, tenoplasties or tendon transfers.
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Introdução: O leiomioma vesical é um tumor benigno raro que representa,aproximadamente, 0,5% do total de neoplasias da bexiga. É frequentemente um achado imagiológico, sendo a sua localização e dimensões determinantes no desenvolvimento de sintomatologia e no tipo de procedimento a efectuar. Caso Clínico: Reporta-se o caso de um doente com queixas urinárias de disúria, polaquiúria e esforço miccional, inicialmente interpretadas como HBP. A investigação diagnóstica culminou com a enucleação de uma volumosa massa intramural da bexiga, com diagnóstico histológico de leiomioma, num doente com antecedentes de doença de Madelung e excisão prévia de um tumor fibroso paravesical. Discussão: O leiomioma vesical, embora apresentando características imagiológicas típicas, deve ser sempre biopsado para confirmação histológica da sua etiologia. O tumor fibroso pélvico apresenta sempre indicação cirúrgica pois, numa minoria de casos, pode apresentar comportamento agressivo com infiltração dos órgãos adjacentes.
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Glass fibre-reinforced plastics (GFRP), nowadays commonly used in the construction, transportation and automobile sectors, have been considered inherently difficult to recycle due to both the cross-linked nature of thermoset resins, which cannot be remoulded, and the complex composition of the composite itself, which includes glass fibres, polymer matrix and different types of inorganic fillers. Hence, to date, most of the thermoset based GFRP waste is being incinerated or landfilled leading to negative environmental impacts and additional costs to producers and suppliers. With an increasing awareness of environmental matters and the subsequent desire to save resources, recycling would convert an expensive waste disposal into a profitable reusable material. In this study, the effect of the incorporation of mechanically recycled GFRP pultrusion wastes on flexural and compressive behaviour of polyester polymer mortars (PM) was assessed. For this purpose, different contents of GFRP recyclates (0%, 4%, 8% and 12%, w/w), with distinct size grades (coarse fibrous mixture and fine powdered mixture), were incorporated into polyester PM as sand aggregates and filler replacements. The effect of the incorporation of a silane coupling agent was also assessed. Experimental results revealed that GFRP waste filled polymer mortars show improved mechanical behaviour over unmodified polyester based mortars, thus indicating the feasibility of GFRP waste reuse as raw material in concrete-polymer composites.
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It is known that the fibrous structure of muscle causes light scattering. This phenomenon occurs due to the refractive index discontinuities located between muscle fibers and interstitial fluid. To study the possibility of reducing light scattering inside muscle, we consider its spectral transmittance evolution during an immersion treatment with an optical clearing solution containing ethanol, glycerol, and distilled water. Our methodology consists of registering spectral transmittance of muscle samples while immersed in that solution. With the spectral data collected, we represent the transmittance evolution for some wavelengths during the treatment applied. Additionally, we study the variations that the treatment has caused on the samples regarding tissue refractive index and mass. By analyzing microscopic photographs of tissue cross section, we can also verify changes in the internal arrangement of muscle fibers caused by the immersion treatment. Due to a mathematical model that we develop, we can explain the variations observed in the studied parameters and estimate the amount of optical clearing agent that has diffused into the tissue samples during the immersion treatment. At the end of the study, we observe and explain the improvement in tissue spectral transmittance, which is approximately 65% after 20 min.
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Antiphospholipid syndrome nephropathy and lupus nephritis have similar clinical and laboratory manifestations and achieving the accuracy of diagnosis required for correct treatment frequently necessitates a kidney biopsy. We report the case of a 29-year-old woman referred to the nephrology service for de novo hypertension, decline of renal function and proteinuria. She had had systemic lupus erythematosus and antiphospholipid syndrome since the age of 21 and was taking oral anticoagulation. Two weeks later, after treatment of hypertension and achievement of adequate coagulation parameters, a percutaneous renal biopsy was performed. The biopsy revealed chronic lesions of focal cortical atrophy, arterial fibrous intimal hyperplasia and arterial thromboses, which are typical features of antiphospholipid syndrome nephropathy. We describe the clinical manifestations and histopathology of antiphospholipid syndrome nephropathy and review the literature on renal biopsy in patients receiving anticoagulation.
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Precocious puberty, defined as the development of secondary sexual characteristics before the age of 8, often leads to anxiety in patients and their families but also in clinicians searching for the final diagnosis. After adequate investigation, the majority of the cases in girls turn out to be idiopathic. The authors present a case of McCune Albright syndrome in order to call attention to a rare cause of sexual precocity and the value of ultrasound in the evaluation of these situations. 10 years old infant girl admitted in our department due to irregular menstrual bleeding. She experienced a vaginal bleeding by the age of 3 which led to the diagnosis of McCune Albright Syndrome after a complete evaluation. Pubertal assessment revealed a reversed sequence in the remaining events with adrenarche at 5 and thelarche at 8. Hormonal evaluation demonstrated low FSH and LH levels (11,2 and 6,72 respectively) with high estrogen (204). Pelvic ultrasound showed a normal sized uterus (73x 29x32 mm), endometrial thickness of 5 mm and ovaries with several microfollicles and a copus luteum measuring 23 mm in the right ovary. McCune Albright syndrome is a very uncommon cause of sexual precocity that should, however, be suspected in all infant girls who present with vaginal bleeding. It is characterized by a triad: polyostotic fibrous dysplasia, gonadotropin-independent precocious puberty and café-au-lait skin spots. Due to autonomous production of estrogen by the ovaries, ultrasound image of the female reproductive tract is inconsistent with chronologic age. Pelvic ultrasound demonstrates a normal sized uterus with a well defined cervix and clearly identified ovaries with several follicles, similar to adult women of reproductive age. Ultrasonography of the pelvis has also an important role excluding other causes of GnRH-independent precocious puberty conditions like ovarian cysts or tumors.
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We report a case of a woman, aged 53 years, presenting with a right atrial mass due to idiopathic fibrosing mediastinitis with periaortic involvement. This challenging diagnosis was confirmed by different imaging modalities and histopathologic analysis. The diagnosis of cardiac tumours is often difficult. To our knowledge, this is the first reported case of an intracavitary cardiac mass due to fibrosing mediastinitis. This rare disorder, which is characterized by invasive proliferation of fibrous tissue within the mediastinum, should be included in the differential diagnosis of intracardiac tumours.
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Pretende-se neste trabalho fazer uma revisão retrospectiva duma patologia, rara na sua incidência(5% de todos os tumores pleurais) e singular nas suas características, analisando na nossa casuística as formas de apresentação, terapêutica cirúrgica e resultados obtidos. Os tumores solitários da pleura são formações neoplásicas raras, cujo comportamento biológico não é obrigatoriamente correlacionável com características imuno-histoquímicas, pois os considerados benignos apresentam um sensível índice de recidiva e metastização, independentemente do volume que apresentam. A cirurgia é o único tratamento disponível e a excisão cirúrgica completa é decisiva para a cura. De Agosto de 1995 a Janeiro de 2003, na casuística do Serviço de Cirurgia Cardiotorácica do Hospital de Santa Marta, foram analisados todos os doentes com o diagnóstico de tumor fibroso localizado da pleura (TFLP). Neste contexto, identificaram-se 11 doentes com idade média de 57,54 anos, dos quais 6 do sexo feminino, em que foi colocado o diagnóstico de tumor fibroso localizado da pleura; 6 dos tumores foram classificados como malignos e 5 como benignos. Nesta série, todos os doentes foram submetidos a intervenção cirúrgica, com técnicas variadas, sem mortalidade intra-operatória ou morbilidade intra-hospitalar significativas, apesar da dificuldade da cirurgia nos tumores mais volumosos (um dos tumores pesava 2,5 kg). O follow up decorreu entre os 4 e os 84 meses (média – 39,4 meses). Um doente faleceu 13 meses após a intervenção, por embolia pulmonar maciça, depois de várias crises de tromboembolismo pulmonar (sem relação determinável com a cirurgia ou a patologia base), apesar da anticoagulação iniciada e controlada na Consulta do Hospital.
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An instrument consisting of a sheath-like tube 22 1/2 cm. long with a rod or trocar and attached cutting blade is described. It may be used to obtain fragments of non hollow organs, 7mm wide by five to ten centimeters long, to substitute the classic viscerotome. No failures have occurred in viscerotomies of the liver so far. The greatest advantage of this instrument is its relatively small size. Its more practical use is to overcome the difficulties which may hamper the use of the classical viscerotome. This is very important as the need arose to reorganize the network of viscerotomy service. In some areas or countries where no complete autopsies can be performed, biopsy samples have been reduced to such a small size that no practical Information has been received in the last few years. The difficulties of performing an autopsy prevents the obtention of useful vathological data on several diseases affecting the population, even among putients dying in hospitais. The viscerotomy is also the practical solution for this problem.
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Dependendo da localização e do número de ossos envolvidos, a Displasia Fibrosa (D.F.) crânio-facial pode ser responsável por síndromes dismórficos e por sintomatologia otológica, oftalmológica ou rinológica. Este artigo tem por objectivo i1ustrar dois casos clínicos de D. F. Poliostótica com envolvimento predominante dos ossos temporal a etmóide. No primeiro caso clínico o envolvimento do osso temporal é responsável por síndrome vertiginoso resultante de hipofunção vestibular esquerda e da obliteração do aqueduto vestibular homolateral. Neste coso o doente foi submetido a neurectomia dos nervos vestibulares, por via retrosigmóide. O segundo caso clínico é um caso de D.F. predominantemente do osso etmóide, acompanhado de proptose e obstrução nasal, em que se procedeu à excisão total por via paralateronasal sob controlo endoscópico. Os autores fazem uma revisão da literatura sobre a clínica, o diagnóstico, e a terapêutica do da doença a nível crânio-facial.
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Introduction: Brachial plexus (BP) tumors are very rare tumors, with less than 800 cases been described in the literature worldwide since 1970. These tumors often present as local or radicular pain, with scant or no neurological deficits. These symptoms are shared by many other more common rheumatologic diseases, thus making their diagnosis difficult in most cases. Additionally, these tumors often present as lumps and are therefore biopsied, which carries a significant risk of iatrogenic nerve injury. Material and Methods: In this paper the authors describe their experience with the management of 5 patients with BP tumors followed up for at least 2 years. There were 4 males and 1 female. Median follow-up time was 41 ± 21 months. Average age at diagnosis was 40,0 ± 19,9 years. The most common complaints at presentation were pain and sensibility changes. All patients had a positive Tinel sign when the lesion was percussed. In all patients surgery was undertaken and the tumors removed. In 4 patients nerve integrity was maintained. In one patient with excruciating pain a segment of the nerve had to be excised and the nerve defect was bridged with sural nerve grafts. Results: Pathology examination of the resected specimens revealed a Schwannoma in 4 cases and a neurofibroma in the patient submitted to segmental nerve resection. Two years postoperatively, no recurrences were observed. All patients revealed clinical improvement. The patient submitted to nerve resection had improvement in pain, but presented diminished strength and sensibility in the involved nerve territory. Conclusion: Surgical excision of BP tumors is not a risk free procedure. Most authors suggest surgery if the lesion is symptomatic or progressing in size. If the tumor is stationary and not associated with neurological dysfunction a conservative approach should be taken.
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Materials Science Forum Vols. 730-732 (2013) pp 617-622