999 resultados para NERVE SHEATH TUMOR
Resumo:
Insect ganglia are often composed of fused segmental units or neuromeres. We estimated the evolution of the ventral nerve cord (VNC) in higher Diptera by comparing the patterns of neuromere fusion among 33 families of the Brachycera. Variation within families is uncommon, and VNC architecture does not appear to be influenced by body shape. The outgroup pattern, seen in lower Diptera, is fusion of neuromeres belonging to thoracic segments 1 and 2 (T1 and T2), and fusion of neuromeres derived from T3 and abdominal segment 1 (A1). In the abdomen, neuromeres A7-10 are fused into the terminal abdominal ganglion (TAG). Increased neuromere fusion is a feature of the Brachycera. No brachyceran shows less fusion than the outgroups. We established six pattern elements; (1) fusion of T1 and T2, (2) fusion of T3 and A1, (3) fusion of the T1/T2 andT3/A1 ganglia, (4) increase in the number of neuromeres comprising the TAG, (5) anteriorward fusion of abdominal neuromeres, and (6) the complete fusion of thoracic and abdominal neuromeres into a synganglion. States 1 and 2 are present in the outgroup lower Diptera, and state 3 in the Xylophagomorpha, Stratiomyomorpha, Tabanomorpha and Cyclorrhapha. State 4 is a feature of all Eremoneura. State 5 is present in Cyclorrhapha only, and state 6, fusion into a synganglion, has evolved at least 4 times in the Eremoneura. Synapomorphies are provided for the Cyclorrhapha and Muscoidea, and a grouping of three basal brachyceran infraorders Xylophagomorpha, Stratiomyomorpha and Tabanomorpha. The patterns of fusion suggest that VNC architecture has evolved irreversibly, in accordance with Dollo's law.
Resumo:
Involvement of nerve tissue may contribute to the persistence of pain following a whiplash injury. This study aimed to investigate responses to the brachial plexus provocation test (BPPT) in 156 subjects with chronic whiplash associated disorder (WAD) with and without associated arm pain and 95 asymptomatic control subjects. The range of elbow extension (ROM) and visual analogue scale (VAS) pain scores were measured. Subjects with chronic WAD demonstrated significantly less ROM and higher VAS scores with the BPPT than the asymptomatic subjects (P
Resumo:
Axonal regeneration of retinal ganglion cells (RGCs) into a normal or pre-degenerated peripheral nerve graft after an optic nerve pre-lesion was investigated. A pre-lesion performed 1-2 weeks before a second lesion has been shown to enhance axonal regeneration in peripheral nerves (PN) but not in optic nerves (ON) in mammals. The lack of such a beneficial pre-lesion effect may be due to the long delay (1-6 weeks) between the two lesions since RGCs and their axons degenerate rapidly 1-2 weeks following axotomy in adult rodents. The present study examined the effects of the proximal and distal ON pre-lesions with a shortened delay (0-8 days) on axonal regeneration of RGCs through a normal or pre-degenerated PN graft. The ON of adult hamsters was transected intraorbitallv at 2 mm. (proximal lesion) or intracranially at 7 mm (distal lesion) from the optic disc. The pre-lesioned ON was re-transected at 0.5 mm from the disc after 0, 1, 2, 4, or 8 days and a normal or a pre-degenerated PN graft was attached onto the ocular stump. The number of RGCs regenerating their injured axons into the PN graft was estimated by retrograde labeling with FluoroGold 4 weeks after grafting. The number of regenerating RGCs decreased significantly when the delay-time increased in animals with both the ON pre-lesions (proximal or distal) compared to control animals without an ON pre-lesion. The proximal ON pre-lesion significantly reduced the number of regenerating RGCs after a delay of 8 days in comparison with the distal lesion. However, this adverse effect can be overcome, to some degree, by a pre-degenerated PN graft applied 2, 4, or 8 days after the distal ON pre-lesion enhanced more RGCs to regenerate than the normal PN graft. Thus, in order to obtain the highest number of regenerating RGCs, a pre-degenerated PN should be grafted immediately after an ON lesion.
Resumo:
We report a 12-month-old infant who presented with a 4-month history of isosexual precocious puberty secondary to an estrogenizing Sertoli-Leydig cell tumor of the ovary. Total serum immunoreactive inhibin and subunits A and B were markedly elevated before surgical resection and subsequently decreased 7 wk later into the normal prepubertal range. Twenty weeks following surgical removal, the patient presented again with central precocious puberty; inhibin B levels were raised on this occasion, a luteinizing releasing hormone stimulation test confirmed central precocious puberty. This is the youngest reported occurrence of this rare sex cord stromal neoplasm. The prognosis of this extremely rare tumor presenting at this early juvenile stage is uncertain. This report illustrates the usefulness of serum inhibin as a tumor marker during therapeutic suppression with leuprorelin acetate for central precocious puberty. Analysis of genomic and tumor DNA revealed a normal nucleotide sequence for the LH receptor and the G{alpha}s gene. To understand the molecular pathogenesis of this tumor we analyzed mRNA levels for the inhibin A and B subunits, FSH receptor, LH receptor aromatase, steroidogenic factor-1 and the ER ß genes. Molecular characterization reveals the presence of genes specific for granulosa and Leydig cells; the relative expression of these genes, in addition to its histologic characteristics, suggests that this tumor may result from a dysdifferentiation of a primordial follicle.
Resumo:
Background: The response of hepatocellular carcinoma (HCC) to therapy is often disappointing and new modalities of treatment are clearly needed. Active immunotherapy based on the injection of autologous dendritic cells (DC) co-cultured ex vivo with tumor antigens has been used in pilot studies in various malignancies such as melanoma and lymphoma with encouraging results. Methods: In the present paper, the preparation and exposure of patient DC to autologous HCC antigens and re-injection in an attempt to elicit antitumor immune responses are described. Results: Therapy was given to two patients, one with hepatitis C and one with hepatitis B, who had large, multiple HCC and for whom no other therapy was available. No significant side-effects were observed. The clinical course was unchanged in one patient, who died a few months later. The other patient, whose initial prognosis was considered poor, is still alive and well more than 3 years later with evidence of slowing of tumor growth based on organ imaging. Conclusions: It is concluded that HCC may be a malignancy worthy of DC trials and sufficient details in the present paper are given for the protocol to be copied or modified. (C) 2002 Blackwell Publishing Asia Pty Ltd.
Resumo:
The apparent L-[H-3]glutamate uptake rate (v') was measured in synaptic vesicles isolated from cerebral cortex synaptosomes prepared from autopsied Alzheimer and non-Alzheimer dementia cases, and age-matched controls. The initial synaptosome preparations exhibited similar densities of D-[H-3]aspartate membrane binding sites (B-MAX values) in the three groups. In control brain the temporal cortex D-[H-3]aspartate B-MAX was 132% of that in motor cortex, parallel with the L- [H-3]glutamate v' values (temporal = 139% of motor; NS). Unlike D- [H-3]aspartate B-MAX values, L- [H-3]glutamate v' values were markedly and selectively lower in Alzheimer brain preparations than in controls, particularly in temporal cortex. The difference could not be attributed to differential effects of autopsy interval or age at death. Non-Alzheimer dementia cases resembled controls. The selective loss of vesicular glutamate transport is consistent with a dysfunction in the recycling of transmitter glutamate.
Resumo:
This study investigated the haemodynamic response to the 90-minute application of 85 Hz transcutaneous electrical nerve stimulation (TENS) to the T1 and T5 nerve roots. Comparison was made between 20 healthy subjects who had TENS stimulation and a separate group of 20 healthy subjects who rested for 90 minutes. Pulse and blood pressure were measured just prior to the start of TENS stimulation, after 30 minutes of stimulation, and after 90 minutes of stimulation (immediately after stopping TENS) or at completion of the rest time depending on group allocation. The rate pressure product was calculated from the pulse and systolic blood pressure data. Multivariate repeated measures analysis showed a significant group effect for TENS (p = 0.048). Univariate repeated measures analyses showed a significant group by time effect due to TENS on systolic blood pressure over the 90-minute time period (p = 0.028). Separate group repeated measures ANOVA showed a significant decline in heart rate (p = 0.000), systolic blood pressure (p = 0.013) and rate pressure product (p = 0.000) for the TENS group, while the control resting group showed a significant decline in heart rate only (p = 0.04). The application of 85 Hz TENS to the upper thoracic nerve roots causes no adverse haemodynamic effects in healthy subjects.
Resumo:
WT1 encodes a transcription factor involved in kidney development and tumorigenesis. Using representational difference analysis, we identified a new set of WT1 targets, including a homologue of the Drosophila receptor tyrosine kinase regulator, sprouty. Sprouty1 was up-regulated in cell lines expressing wild-type but not mutant WT1. WT1 bound to the endogenous sprouty1 promoter in vivo and directly regulated sprouty1 through an early growth response gene-1 binding site. Expression of Sprouty1 and WT1 overlapped in the developing metanephric mesenchyme, and Sprouty1, like WT1, plays a key role in the early steps of glomerulus formation. Disruption of Sprouty1 expression in embryonic kidney explants by antisense oligonucleotides reduced condensation of the metanephric mesenchyme, leading to a decreased number of glomeruli. In addition, sprouty1 was expressed in the ureteric tree and antisense-treated ureteric trees had cystic lumens. Therefore, sprouty1 represents a physiologically relevant target gene of WT1 during kidney development.
Resumo:
We show here that nerve growth factor (NGF), the canonical neurotrophic factor, is synthesized and released by breast cancer cells. High levels of NGF transcript and protein were detected in breast cancer cells by reverse transcription-PCR, Western blotting, ELISA assay and immunohistochemistry. Conversely, NGF production could not be detected in normal breast epithelial cells at either the transcriptional or protein level. Confocal analysis indicated the presence of NGF within classical secretion vesicles. Breast cancer cell-produced NGF was biologically active, as demonstrated by its ability to induce the neuronal differentiation of embryonic neural precursor cells. Importantly, the constitutive growth of breast cancer cells was strongly inhibited by either NGF-neutralizing antibodies or K-252a, a pharmacological inhibitor of NGF receptor TrkA, indicating the existence of an NGF autocrine loop. Together, our data demonstrate the physiological relevance of NGF in breast cancer and its potential interest as a marker and therapeutic target.
Resumo:
Up-regulation of receptor-ligand pairs during interaction of an MHC-presented epitope on dendritic cells (DCs) with cognate TCR may amplify, sustain, and drive diversity in the ensuing T cell immune response. Members of the TNF ligand superfamily and the TNFR superfamily contribute to this costimulatory molecule signaling. In this study, we used replication deficient adenoviruses to introduce a model tumor-associated Ag (the E7 oncoprotein of human papillomavirus 16) and the T cell costimulatory molecule 4-IBBL into murine DCs, and monitored the ability of these recombinant DO to elicit E7-directed T cell responses following immunization. Splenocytes from mice immunized with DCs expressing E7 alone elicited E7-directed effector and memory CTL responses. Coexpression of 4-1BBL in these E7-expressing DO increased effector and memory CTL responses when they were used for immunization. 4-1BBL expression up-regulated CD80 and CD86 second signaling molecules in DO. We also report an additive effect of 4-IBBL and receptor activator of NF-kappaB/receptor activator of NF-kappaB ligand coexpression in E7-transduced DC inummogens on E7-directed effector and memory CTL responses and on MHC class II and CD80/86 expression in DCs. Additionally, expression of 4-1BBL in E7-transduced DCs reduced nonspecific T cell activation characteristic of adenovirus vector-associated immunization. The results have generic implications for improved or tumor Ag-expressing DC vaccines by incorporation of exogenous 4-1BBL. There are also specific implications for an improved DC-based vaccine for human papillomavirus 16-associated cervical carcinoma.
Resumo:
The role of natural killer T (NKT) cells in the immune response to tumor cells has been largely unexplored. As a model of adoptive tumor immunotherapy, cells from the draining lymph nodes of mice immunized with a tumor-specific or irrelevant antigen were transferred to naive recipients with established tumor. Inhibition of early tumor growth (day 4) required the transfer of both CD8(+) and Jalpha18(+) (NKT) cells from immunized animals without regard to immunogen. In contrast, CD8(+) cells, but not Jalpha18(+) cells, were necessary for the inhibition of late tumor growth (day 8). Thus, the developing tumor changes in sensitivity to NKT-mediated events and the role for NKT cells cannot be replaced by the presence of tumor-specific cells during early tumor growth. This suggests that recruitment/activation of Jalpha18(+) NKT cells is an important consideration during the immune therapy of early stage tumors.
Resumo:
The outcome of dendritic cell (DC) presentation of Ag to T cells via the TCR/MHC synapse is determined by second signaling through CD80/86 and, importantly, by ligation of costimulatory ligands and receptors located at the DC and T cell surfaces. Downstream signaling triggered by costimulatory molecule ligation results in reciprocal DC and T cell activation and survival, which predisposes to enhanced T cell-mediated immune responses. In this study, we used adenoviral vectors to express a model tumor Ag (the E7 oncoprotein of human papillomavirus 16) with or without coexpression of receptor activator of NF-kappaB (RANK)/RANK ligand (RANKL) or CD40/CD40L costimulatory molecules, and used these transgenic DCs to immunize mice for the generation of E7-directed CD8(+) T cell responses. We show that coexpression of RANK/RANKL, but not CD40/CD40L, in E7-expressing DCs augmented E7-specific IFN-gamma-secreting effector and memory T cells and E7-specific CTLs. These responses were also augmented by coexpression of T cell costimulatory molecules (RANKL and CD40L) or DC costimulatory molecules (RANK and CD40) in the E7-expressing DC immunogens. Augmentation of CTL responses correlated with up-regulation of CD80 and CD86 expression in DCs transduced with costimulatory molecules, suggesting a mechanism for enhanced T cell activation/survival. These results have generic implications for improved tumor Ag-expressing DC vaccines, and specific implications for a DC-based vaccine approach for human papillomavirus 16-associated cervical carcinoma.
Resumo:
INTRODUÇÃO: A neoangiogênese e a resposta imunológica são mecanismos importantes no desenvolvimento das metástases. OBJETIVO: Avaliar a reatividade linfonodal e a densidade microvascular nas metástases cervicais de carcinoma epidermóide com tumor primário oculto, considerando a sua relação com outras variáveis histológicas e clínicas. TIPO DE ESTUDO: Série de casos, retrospectiva. CASUÍSTICA E MÉTODO: 19 pacientes submetidos a esvaziamento cervical entre 1983 e 2000. Os linfonodos foram reavaliados quanto ao tipo de reatividade, considerando a área cortical e paracortical. Nas metástases foi avaliado o grau de diferenciação, desmoplasia, necrose, e densidade microvascular (CD34). Foi estabelecida a relação entre as diferentes variáveis histológicas e clínicas, incluindo o estadiamento e a evolução dos pacientes. RESULTADOS: A densidade microvascular apresentou mediana de 91 vasos/mm2, variando de 28 a 145. A reatividade paracortical foi mais freqüente nos pacientes com menos de 55 anos (90% x 44%, p= 0,05). A sobrevida livre de doença foi de 52% em 3 anos, sendo similar entre os pacientes com maior ou menor densidade microvascular tumoral. CONCLUSÕES: A densidade microvascular nas metástases de tumor primário oculto apresenta grande variação individual. Não foi possível estabelecer relação entre a densidade microvascular e as variáveis clínicas e histológicas estudadas.
Resumo:
O tumor odontogênico adenomatóide é uma lesão relativamente incomum, que acomete preferencialmente indivíduos do sexo feminino durante a segunda década de vida, exibindo como sítio de predileção a região anterior da maxila. A lesão geralmente está associada à coroa de um dente incluso, comumente o canino. Neste trabalho é relatado o caso de um tumor odontogênico adenomatóide associado a cisto dentígero ocorrendo na região maxilar esquerda, em paciente do sexo feminino com 13 anos de idade, discutindo-se, ainda, as características clínicas, radiográficas, histopatológicas e terapêuticas do caso.