36 research outputs found
Mimicking the Neurotrophic Factor Profile of Embryonic Spinal Cord Controls the Differentiation Potential of Spinal Progenitors into Neuronal Cells
Recent studies have indicated that the choice of lineage of neural progenitor cells is determined, at least in part, by environmental factors, such as neurotrophic factors. Despite extensive studies using exogenous neurotrophic factors, the effect of endogenous neurotrophic factors on the differentiation of progenitor cells remains obscure. Here we show that embryonic spinal cord derived-progenitor cells express both ciliary neurotrophic factor (CNTF) and brain-derived neurotrophic factor (BDNF) mRNA before differentiation. BDNF gene expression significantly decreases with their differentiation into the specific lineage, whereas CNTF gene expression significantly increases. The temporal pattern of neurotrophic factor gene expression in progenitor cells is similar to that of the spinal cord during postnatal development. Approximately 50% of spinal progenitor cells differentiated into astrocytes. To determine the effect of endogenous CNTF on their differentiation, we neutralized endogenous CNTF by administration of its polyclonal antibody. Neutralization of endogenous CNTF inhibited the differentiation of progenitor cells into astrocytes, but did not affect the numbers of neurons or oligodendrocytes. Furthermore, to mimic the profile of neurotrophic factors in the spinal cord during embryonic development, we applied BDNF or neurotrophin (NT)-3 exogenously in combination with the anti-CNTF antibody. The exogenous application of BDNF or NT-3 promoted the differentiation of these cells into neurons or oligodendrocytes, respectively. These findings suggest that endogenous CNTF and exogenous BDNF and NT-3 play roles in the differentiation of embryonic spinal cord derived progenitor cells into astrocytes, neurons and oligodendrocytes, respectively
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Criteria for the definition of Pituitary Tumor Centers of Excellence (PTCOE): A Pituitary Society Statement
Introduction
With the goal of generate uniform criteria among centers dealing with pituitary tumors and to enhance patient care, the Pituitary Society decided to generate criteria for developing Pituitary Tumors Centers of Excellence (PTCOE).
Methods
To develop that task, a group of ten experts served as a Task Force and through two years of iterative work an initial draft was elaborated. This draft was discussed, modified and finally approved by the Board of Directors of the Pituitary Society. Such document was presented and debated at a specific session of the Congress of the Pituitary Society, Orlando 2017, and suggestions were incorporated. Finally the document was distributed to a large group of global experts that introduced further modifications with final endorsement.
Results
After five years of iterative work a document with the ideal criteria for a PTCOE is presented.
Conclusions
Acknowledging that very few centers in the world, if any, likely fulfill the requirements here presented, the document may be a tool to guide improvements of care delivery to patients with pituitary disorders. All these criteria must be accommodated to the regulations and organization of Health of a given country
Pituitary society expert Delphi consensus: operative workflow in endoscopic transsphenoidal pituitary adenoma resection
Abstract: Purpose: Surgical workflow analysis seeks to systematically break down operations into hierarchal components. It facilitates education, training, and understanding of surgical variations. There are known educational demands and variations in surgical practice in endoscopic transsphenoidal approaches to pituitary adenomas. Through an iterative consensus process, we generated a surgical workflow reflective of contemporary surgical practice. Methods: A mixed-methods consensus process composed of a literature review and iterative Delphi surveys was carried out within the Pituitary Society. Each round of the survey was repeated until data saturation and > 90% consensus was reached. Results: There was a 100% response rate and no attrition across both Delphi rounds. Eighteen international expert panel members participated. An extensive workflow of 4 phases (nasal, sphenoid, sellar and closure) and 40 steps, with associated technical errors and adverse events, were agreed upon by 100% of panel members across rounds. Both core and case-specific or surgeon-specific variations in operative steps were captured. Conclusions: Through an international expert panel consensus, a workflow for the performance of endoscopic transsphenoidal pituitary adenoma resection has been generated. This workflow captures a wide range of contemporary operative practice. The agreed “core” steps will serve as a foundation for education, training, assessment and technological development (e.g. models and simulators). The “optional” steps highlight areas of heterogeneity of practice that will benefit from further research (e.g. methods of skull base repair). Further adjustments could be made to increase applicability around the world
Prolactinomas, Cushing's disease and acromegaly: debating the role of medical therapy for secretory pituitary adenomas
Pituitary adenomas are associated with a variety of clinical manifestations resulting from excessive hormone secretion and tumor mass effects, and require a multidisciplinary management approach. This article discusses the treatment modalities for the management of patients with a prolactinoma, Cushing's disease and acromegaly, and summarizes the options for medical therapy in these patients
Precipitating factors in pituitary apoplexy
Pituitary apoplexy is a rare but life threatening condition caused by sudden haemorrhage or infarction of the pituitary gland. Potential precipitating factors in the occurrence of acute pituitary apoplexy in 30 consecutive patients were identified and compared with the clinical characteristics and outcome of patients with and without associated factors. Six patients had a previously known pituitary adenoma. All patients complained of severe headaches, associated with neuro-ophthalmological symptoms and signs in 83% and altered mental status in 30%. Potential risk factors were identified in nine patients (30%). When there was an associated factor, the clinical presentation was no different than in patients without such factors although altered mental status may be more frequent in patients with associated diseases. In these patients, the visual prognosis was worse and the diagnosis was more difficult to establish. Acute pituitary apoplexy is unpredictable and should be considered in any patient with abrupt neuro-ophthalmological deterioration associated with headache. Patients with pituitary apoplexy often have an associated disease that confounds recognition and treatment despite a typical presentation.