972 resultados para Neoplasms, unknown primary
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Background Cortical cultures grown long-term on multi-electrode arrays (MEAs) are frequently and extensively used as models of cortical networks in studies of neuronal firing activity, neuropharmacology, toxicology and mechanisms underlying synaptic plasticity. However, in contrast to the predominantly asynchronous neuronal firing activity exhibited by intact cortex, electrophysiological activity of mature cortical cultures is dominated by spontaneous epileptiform-like global burst events which hinders their effective use in network-level studies, particularly for neurally-controlled animat (‘artificial animal’) applications. Thus, the identification of culture features that can be exploited to produce neuronal activity more representative of that seen in vivo could increase the utility and relevance of studies that employ these preparations. Acetylcholine has a recognised neuromodulatory role affecting excitability, rhythmicity, plasticity and information flow in vivo although its endogenous production by cortical cultures and subsequent functional influence upon neuronal excitability remains unknown. Results Consequently, using MEA electrophysiological recording supported by immunohistochemical and RT-qPCR methods, we demonstrate for the first time, the presence of intrinsic cholinergic neurons and significant, endogenous cholinergic tone in cortical cultures with a characterisation of the muscarinic and nicotinic components that underlie modulation of spontaneous neuronal activity. We found that tonic muscarinic ACh receptor (mAChR) activation affects global excitability and burst event regularity in a culture age-dependent manner whilst, in contrast, tonic nicotinic ACh receptor (nAChR) activation can modulate burst duration and the proportion of spikes occurring within bursts in a spatio-temporal fashion. Conclusions We suggest that the presence of significant endogenous cholinergic tone in cortical cultures and the comparability of its modulatory effects to those seen in intact brain tissues support emerging, exploitable commonalities between in vivo and in vitro preparations. We conclude that experimental manipulation of endogenous cholinergic tone could offer a novel opportunity to improve the use of cortical cultures for studies of network-level mechanisms in a manner that remains largely consistent with its functional role.
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Over the last decades, technical-scientific advances of oncology have brought about an increased survival rate for cancer patients. As a result, oncologists have detected an increased number of patients presenting with other neoplasms. This research aimed to analyze factors related to demography and to the anatomic site in patients having a FPT of the mouth who developed a SPT. Medical charts of 848 patients neoplasm admitted for treatment at the Head and Neck Surgery Department of the Hospital do Cancer, Antonio Candido Camargo, Brazil, from January of 1984 to December, were analysed. of these, 12 6 developed a SPT. 49.21 % were from 51 to 65 years of age, while 83.33% were of the male gender and Caucasian. Regarding FPT site 38.89% were of the tongue, and 28.5% were of the floor of the mouth. The esophagus, excepting skin (13.49%), was more often subject to SPT (11.9%), of these 74.6% were metachronic, 15.87% simultaneous and 9.52% synchronous.
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Chromosome analysis was performed on samples from 20 Brazilian patients with breast cancer. All the samples were from untreated patients who presented the clinical symptoms for months or years before surgical intervention. Six cases showed axillary lymph node metastases. Clonal chromosome abnormalities were detected in all cases. The numerical alterations most frequently observed involved the loss of chromosomes X, 19, 20, and 22 followed by gain of chromosomes 9 and 8. Among the structural anomalies observed, there was preferential involvement of chromosomes 11, 6, 1, 7, 3, and 12, supporting previous reports that these chromosomes may harbour genes of importance in the development of breast tumors. Two cases with a family history of breast cancer had in common total or partial trisomy 1.
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The incidence of secondary testicular tumors ranges from 0.02 to 2.5% among autopsies in general. With the exception of leukemias and lymphomas, prostate cancer is the most common primary site. It is diagnosed in autopsies or incidentally, following therapeutic orchiectomies in more advanced stages of the disease. In the present report, we show a case of testicular metastasis derived from prostate neoplasm whose clinical presentation as a single metastasis was similar to a primary testicular neoplasm. The diagnosis was evidenced after orchiectomy by histological examination and immunohistochemical tests.
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Adenocarcinoma of the lung that metastasizes to the mandible is very uncommon; only a few cases have been described in the English-language literature. This article presents a metastasis from adenocarcinoma of the lung affecting the mandible of a 64-year-old woman, in which the first discovered metastatic lesion was detected before the primary tumor. The immunoreactivity for human thyroid transcription factor-1 (TTF-1) in the oral lesion was essential for determining the site and type of the primary tumor, as the patient showed no clinical or radiographic evidence of a tumor in the thyroid gland. After the primary tumor in the lung was diagnosed, radiotherapy and chemotherapy were initiated; unfortunately, the patient died two months after the start of treatment. This article emphasizes the importance of a well-conducted examination for diagnosing metastatic oral lesions.
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Breast cancer is the most common type of cancer among women worldwide. Research using breast cancer cell lines derived from primary tumors may provide valuable additional knowledge regarding this type of cancer. Therefore, the aim of this study was to investigate the phenotypic profiles of MACL-1 and MGSO-3, the only Brazilian breast cancer cell lines available for comparative studies. We evaluated the presence of hormone receptors, proliferation, differentiation and stem cell markers, using immunohistochemical staining of the primary tumor, cultured cells and xenografts implanted in immunodeficient mice. We also investigated the ability of the cell lines to form colonies and copy number alterations by array comparative genomic hybridization. Histopathological analysis showed that the invasive primary tumor from which the MACL-1 cell line was derived, was a luminal A subtype carcinoma, while the ductal carcinoma in situ (DCIS) that gave rise to the MGSO-3 cell line was a HER2 subtype tumor, both showing different proliferation levels. The cell lines and the tumor xenografts in mice preserved their high proliferative potential, but did not maintain the expression of the other markers assessed. This shift in expression may be due to the selection of an 'establishment' phenotype in vitro. Whole-genome DNA evaluation showed a large amount of copy number alterations (CNAs) in the two cell lines. These findings render MACL-1 and MGSO-3 the first characterized Brazilian breast cancer cell lines to be potentially used for comparative research. © 2013 Spandidos Publications Ltd. All rights reserved.
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Objectives: Primary failure of tooth eruption (PFE) is a rare autosomal-dominant disease characterized by severe lateral open bite as a consequence of incomplete eruption of posterior teeth. Heterozygous mutations in the parathyroid hormone 1 receptor (PTH1R) gene have been shown to cause PFE likely due to protein haploinsufficiency. To further expand on the mutational spectrum of PFE-associated mutations, we report here on the sequencing results of the PTH1R gene in 70 index PFE cases. Materials and methods: Sanger sequencing of the PTH1R coding exons and their immediate flanking intronic sequences was performed with DNA samples from 70 index PFE cases. Results: We identified a total of 30 unique variants, of which 12 were classified as pathogenic based on their deleterious consequences on PTH1R protein while 16 changes were characterized as unclassified variants with as yet unknown effects on disease pathology. The remaining two variants represent common polymorphisms. Conclusions: Our data significantly increase the number of presently known unique PFE-causing PTH1R mutations and provide a series of variants with unclear pathogenicity which will require further in vitro assaying to determine their effects on protein structure and function. Clinical relevance: Management of PTH1R-associated PFE is problematic, in particular when teeth are exposed to orthodontic force. Therefore, upon clinical suspicion of PFE, molecular DNA testing is indicated to support decision making for further treatment options. © 2013 Springer-Verlag Berlin Heidelberg.
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Lower gastrointestinal tract neoplasms are rare in domestic animals, representing 3% of all biopsies and necropsies. Our objective is to describe the histopathological and B-mode ultrasound findings in a case of duodenal adenocarcinoma in a dog, since it commonly occurs in the large intestine. On ultrasound examination, there was transmural wall thickening in the duodenum with loss of layer structure, focal peritonitis and adenopathy. Histopathological examination of the intestinal mass revealed a malignant epithelial neoplasm, densely cellular and infiltrative, extending through the lamina propria, submucosa, muscle and hypodermis, characterizing a duodenal adenocarcinoma. We conclude that adenocarcinomas may be included in the differential diagnosis of transmural lesions in the duodenum in B-mode ultrasound examinations, but a laparotomy and biopsy are required for definitive diagnosis.
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Dentoalveolar ankylosis is described as the direct union between root cementum/dentin and alveolar bone. Its etiology is unknown, and conflicting opinions have been presented to explain it. Late detection of ankylosed primary teeth may cause serious problems to the occlusion and generally demands a more complex treatment approach. The purpose of this report is to present an unusual case of severe infraocclusion of the primary maxillary right second molar associated with a posterior crossbite in a 6-year-old child. The initial treatment option was tooth extraction, but the tooth resumed eruption spontaneously. After correction of the posterior crossbite and a 1-year follow-up, the tooth remained in occlusion and the permanent successor was developing without problems. From this unusual outcome, it may be concluded that further investigation of this anomaly of eruption is needed. (J Dent Child 2013;80(2):88-91)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The diagnosis of T-cell large granular lymphocytic leukemia in association with other B-cell disorders is uncommon but not unknown. However, the concomitant presence of three hematological diseases is extraordinarily rare. We report an 88-year-old male patient with three simultaneous clonal disorders, that is, CD4+/CD8(weak) T-cell large granular lymphocytic leukemia, monoclonal gammopathy of unknown significance and monoclonal B-cell lymphocytosis. The patient has only minimal complaints and has no anemia, neutropenia or thrombocytopenia. Lymphadenopathy and hepatosplenomegaly were not present. The three disorders were characterized by flow cytometry analysis, and the clonality of the T-cell large granular lymphocytic leukemia was confirmed by polymerase chain reaction. Interestingly, the patient has different B-cell clones, given that plasma cells of monoclonal gammopathy of unknown significance exhibited a kappa light-chain restriction population and, on the other hand, B-lymphocytes of monoclonal B-cell lymphocytosis exhibited a lambda light-chain restriction population. This finding does not support the antigen-driven hypothesis for the development of multi-compartment diseases, but suggests that T-cell large granular lymphocytic expansion might represent a direct antitumor immunological response to both B-cell and plasma-cell aberrant populations, as part of the immune surveillance against malignant neoplasms.
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Purpose: To examine the accuracy of a screening programme for potentially malignant disorders of the oral mucosa by visual inspection in primary health care. Materials and Methods: The study was based on secondary data from the Primary Care Information System maintained by seven units of family health in Sao Paulo City managed by a non-governmental agency. The reference population was composed of 15,072 residents 50 years old or more of both genders. The study population comprised 2,980 individuals. During screening in community settings, the oral mucosa was examined by trained dentists and distributed into two categories: (a) screen negative (b) screen positive. All participants underwent comprehensive clinical exams by a general dental practitioner supervised by a specialist. Individual records were grouped in a working dataset. Point and 95% confidence interval estimates were calculated regarding measures of sensitivity (Se), specificity (Sp) and positive and negative predictive values (PPV and NPV, respectively). Results: 18.0% of the population was considered screen positive. A total of 133 lesions (4.5%) were identified and 8 cases of oral cancer were confirmed, which corresponded to a prevalence rate of 27 cases in 10,000 people, a much higher rate than expected. The measures found were Se: 91.7% (85.3-95.6), Sp: 85.4% (84.1-86.7), PPV: 22.7% (19.3-26.5), NPV: 99.5% (99.2-99.8). The visual screen presented high accuracy. Conclusion: The test presented high sensibility and specificity values. From a public health point of view, the high accuracy levels showed the importance of oral health teams on family health strategy for more comprehensive primary care. Targeting risk groups and delegating the screening to community health agents may improve PPV and coverage.
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The DOK1 gene is a putative tumour suppressor gene located on the human chromosome 2p13 which is frequently rearranged in leukaemia and other human tumours. We previously reported that the DOK1 gene can be mutated and its expression down-regulated in human malignancies. However, the mechanism underlying DOK1 silencing remains largely unknown. We show here that unscheduled silencing of DOK1 expression through aberrant hypermethylation is a frequent event in a variety of human malignancies. DOK1 was found to be silenced in nine head and neck cancer (HNC) cell lines studied and DOK1 CpG hypermethylation correlated with loss of gene expression in these cells. DOK1 expression could be restored via demethylating treatment using 5-aza-2'deoxycytidine. In addition, transduction of cancer cell lines with DOK1 impaired their proliferation, consistent with the critical role of epigenetic silencing of DOK1 in the development and maintenance of malignant cells. We further observed that DOK1 hypermethylation occurs frequently in a variety of primary human neoplasm including solid tumours (93% in HNC, 81% in lung cancer) and haematopoietic malignancy (64% in Burkitt's lymphoma). Control blood samples and exfoliated mouth epithelial cells from healthy individuals showed a low level of DOK1 methylation, suggesting that DOK1 hypermethylation is a tumour specific event. Finally, an inverse correlation was observed between the level of DOK1 gene methylation and its expression in tumour and adjacent non tumour tissues. Thus, hypermethylation of DOK1 is a potentially critical event in human carcinogenesis, and may be a potential cancer biomarker and an attractive target for epigenetic-based therapy.
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Abstract Introduction The natural history of patients with spontaneous parathyroid necrosis is unknown. In this case report we describe the clinical course, laboratory, radiographic, bone densitometry tests, parathyroid ultrasonography and scintigraphy examinations of a patient performed over a period of eight years after she first presented with a sudden episode of spontaneous resolution of primary hyperparathyroidism (PHPT). Case presentation A 24-year-old woman with a clinical history and laboratory and radiographic tests compatible with PHPT suffered a sudden episode of cervical pain and presented with clinical evidence of hypocalcemia. Biopsy of a cervical nodule revealed necrotic material compatible with ischemia of the parathyroid. The follow-up of the patient presented four distinct phases: the first, which lasted two years, was compatible with a period of bone hunger during which it was necessary to introduce calcitriol and calcium carbonate. During this period, the patient showed bone mass gain. The second phase was characterized by normalization of calcium and parathyroid hormone levels and its end was difficult to define. During the third phase there was a recurrence of hypercalcemia associated with elevated parathyroid hormone (PTH) levels and loss of bone mass. The last phase corresponded to the interval after parathyroidectomy, which was characterized by normalization of serum levels of calcium and PTH, as well as bone mass gain. Conclusion This case report indicates that spontaneous resolution of PHPT by adenoma necrosis is potentially temporary. Thus, in cases in which a conservative approach is chosen, clinical and laboratory follow-up is indispensable. Bone mass measurement is a useful tool in the follow-up of these cases. However, this option exposes the patient to a potential roller-coaster ride of bone mass gain and loss, whose long term consequences are still unknown.