1,721,094 research outputs found
Sarcomatoid Carcinoma of the Anorectal Junction With Neuroendocrine and Rhabdomyoblastic Features.
No full textA case of sarcomatoid carcinoma of the anorectal junction in a 71-year-old woman showing neuroendocrine and rhabdomyoblastic features is described. The tumor was diffusely infiltrative and metastases to regional lymph nodes were found at laparotomy. The patient died 6 months after surgery with widespread metastases
Supratentorial cortical ependymoma: report of three cases.
No full textOBJECTIVE AND IMPORTANCE: Extraventricular ependymomas account for 50% of supratentorial ependymomas. Some tumors may extend to the gray matter reaching the pial surface, but pure cortical ependymomas are uncommon. Here, we report three patients with supratentorial intracortical ependymoma. CLINICAL PRESENTATION: We reviewed the clinicopathological findings of all patients operated on for ependymomas at the Bellaria Hospital during an 11-year period and found three lesions described as cortical ependymomas. The three lesions represented 2.5% of all ependymal tumors and 21.4% of supratentorial tumors operated on during the study period. The patient were aged 52, 24, and 11 years (mean, 32.3 yr). One was female. All presented with seizures. On imaging, the lesions were confined to the gray matter, were solid, and demonstrated diffuse enhancement. INTERVENTION: Gross total resection was achieved in all instances. Two patients were treated with surgery, and one was treated with surgery and postoperative radiotherapy. All tumors were low grade. After a mean follow-up of 92.6 months, no patient had recurrence or leptomeningeal dissemination. Review of preoperative magnetic resonance imaging scans confirmed an intracortical location. Routine sections were reviewed, and additional immunoreactions for epithelial membrane antigen, glial fibrillary acidic protein, synaptophysin, neurofilament proteins, S-100 protein, and Ki-67 and electron microscopy were performed. CONCLUSION: Cortical ependymomas seem to behave as benign tumors amenable to surgical removal. Local recurrence and leptomeningeal dissemination seem to be unlikely. Postoperative radiotherapy is unnecessary
Low levels of cobalamin, epidermal growth factor, and normal prions in multiple sclerosis spinal cord
No full textWe have previously demonstrated that multiple sclerosis (MS) patients have abnormal cerebrospinal fluid (CSF) levels of the key myelin-related molecules cobalamin (Cbl), epidermal growth factor (EGF), and normal cellular prions (PrPCs), thus confirming that some CSF abnormalities may be co-responsible for remyelination failure. We determined the levels of these three molecules in post-mortem spinal cord (SC) samples taken from MS patients and control patients. The control SC samples, almost all of which came from non-neurological patients, did not show any microscopic lesions of any type. All of the samples were supplied by the U.K. MS Tissue Bank. The Cbl, EGF, and PrPC levels were determined using enzyme-linked immunosorbent assays. The SC total homocysteine level was determined using a competitive immunoenzymatic assay. CSF samples, taken from a further group of MS patients, were used for the assay of holo-transcobalamin (holo-TC) levels. The Cbl, EGF, and PrPC levels were significantly decreased in MS SCs in comparison with controls and, paradoxically, the decreased Cbl levels were associated with decreased SC levels of homocysteine, a biochemical marker of Cbl deficiency. The trends of EGF and PrPC levels paralleled those previously found in CSF, whereas that of Cbl was the opposite. There was no significant difference in CSF holo-TC levels between the MS patients and the controls. Given that we have previously demonstrated that Cbl positively regulates central nervous system EGF levels, it is conceivable that the low EGF levels in the MS SC may be causally related to a local decrease in Cbl levels. Only PrPC levels were invariably decreased in both the SC and CSF regardless of the clinical course of the disease. These findings suggest that the simultaneous lack of Cbl, EGF, and PrPCs may greatly hamper the remyelination process in MS patients, because they are key molecules of the machinery for remyelination
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Rare primary non-neuroendocrine tumours of the sella
No full textAbout 1% of primary tumour of the sellar region can be diagnostically challenging. The spectrum of these lesions includes lesions that have been codified in 4th edition of the WHO classification of tumours of the pituitary gland published in 2017 such as posterior lobe and neuronal and paraneuronal tumours as well as lesions that have not been included such as the sellar atypical teratoid rhabdoid tumour, salivary gland-like tumours and primary sellar melanocytic tumours. This review aims to provide the diagnostic criteria for these rare lesions and an overview of their essential clinical and neuroimaging features
Levels of p27 sensitize to dual PI3K/mTOR inhibition
No full textConstitutive activation of the phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR signaling cascade occurs in a variety of human malignancies, where it sustains tumor cell proliferation and survival. Pharmacologic blockade of this pathway exerts antineoplastic activity by triggering apoptosis and/or cell-cycle arrest. Pituitary adenomas show activation of the PI3K/AKT/mTOR pathway, but only a fraction of them respond in vitro to the antiproliferative action of rapamycin and RAD001 (mTOR inhibitors), possibly because of the described negative feedback loop on AKT which reactivates the signaling cascade. Rats affected by the multiple endocrine neoplasia-like syndrome (MENX) develop pituitary adenomas showing increased activated AKT. In this study, we comparatively investigated the antitumor potential of the novel dual PI3K/mTOR inhibitor NVP-BEZ235 and the single mTOR inhibitor RAD001 on rat pituitary adenoma cells in primary culture. NVP-BEZ235 inhibits the PI3K pathway both upstream and downstream of AKT, thereby preventing the negative feedback loop. NVP-BEZ235 was more effective than RAD001 in reducing cell viability of pituitary adenomas. Consistently, NVP-BEZ235 treatment decreased Akt and S6 phosphorylation and triggered apoptosis. Because MENX is caused by a germline loss-of-function mutation in the cell-cycle inhibitor p27Kip1, we investigated the relationship between this defect and response to NVP-BEZ235 treatment. The levels of p27Kip1 positively correlate with the response to NVPBEZ235 treatment. Combined treatment with NVP-BEZ235 and the proteasome inhibitor bortezomib, which increases p27Kip1 amount, shows synergistic antiproliferative effects on pituitary adenoma cells. Our data suggest that NVP-BEZ235 may represent an effective therapeutic modality for pituitary adenomas and that p27Kip1 levels represent a potential predictor of response to dual PI3K/mTOR inhibition. ©2011 AACR
Crooke's hyalinization in silent corticotroph adenoma: Report of two cases
No full textCorticotroph adenomas rarely show Crooke's hyaline change in neoplastic cells, a feature similar to that of normal corticotroph cells exposed to excess cortisol. Crooke's cell adenomas are usually associated with Cushing's disease. Nonfunctioning examples are uncommon. We report two clinically silent corticotroph adenomas featuring extensive Crooke's hyalinization in neoplastic cells. The two patients were 49 and 59 yr of age and neither had Cushing's disease. Serum and urinary cortisol were normal. One patient had elevated serum adrenocorticotropic hormone. In our experience, the two patients accounted for 0.4% of pituitary adenomas operated on from January 1992 to December 2001 and 3.5% of all corticotroph adenomas. The two lesions had features of the subtype 1 silent corticotroph adenoma. Cytogenetic analysis performed on one lesion showed a normal karyotype (46;XY). Hyalinization in clinically silent Crooke's cell adenoma indicates that hyaline changes do not always relate to excess cortisol. It is known that neoplastic Crooke's cells show immunoreactivity for glucocorticoid receptors stronger than nontumorous Crooke's corticotrophs. This fact suggests that receptor overexpression or lack of receptor downregulation may result in hypersensitivity of neoplastic Crooke's cells to physiologic cortisol plasma levels
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Colorectal carcinoma to pituitary tumour: tumour to tumour metastasis
No full textWe document a patient with colon adenocarcinoma who presented with rapidly worsening visual impairment. Staging computer tomography and subsequent magnetic resonance scans documented a sellar, suprasellar lesion compressing the optic chiasm. The patient underwent trans-sphenoidal surgery to relieve optic chiasm compression and obtain tissue for diagnosis. Histological examination revealed a metastatic mucinous adenocarcinoma in a gonadotroph pituitary neuroendocrine tumour (PitNET, formerly pituitary adenoma). The patient underwent adjuvant radiotherapy to the sella and chemotherapy but he died nine months after pituitary surgery. This report highlights the diagnostic and management challenges of metastases to PitNET
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