MARCELLO DELANO BRONSTEIN
Projetos de Pesquisa
Unidades Organizacionais
LIM/25 - Laboratório de Endocrinologia Celular e Molecular, Hospital das Clínicas, Faculdade de Medicina
7 resultados
Resultados de Busca
Agora exibindo 1 - 7 de 7
- Editorial: Is macroprolactinemia just a diagnostic pitfall?(2012) BRONSTEIN, Marcello D.
- Pituitary autoimmune disease: nuances in clinical presentation(2012) GLEZER, A.; BRONSTEIN, M. D.Pituitary autoimmune disease is considered an autoimmune organ-specific disorder, characterized by a pituitary infiltration of lymphocytes, macrophages, and plasma cells that could lead to loss of pituitary function. Hypophysitis may be secondary to systemic diseases or infections. Primary pituitary hypophysitis is classified into lymphocytic, granulomatous, xanthomatous, mixed forms (lymphogranulomatous, xanthogranulomatous), necrotizing and IgG4 plasmacytic, according to the histological findings. Concerning lymphocytic hypophysitis (LH), it is characterized by lymphocytic infiltration and can be subclassified according to the affected area on: lymphocytic adenohypophysitis, lymphocytic infundibulo-neurohypophysitis and lymphocytic panhypophysitis. LH had always been considered a rare disease. Nevertheless, with improved imaging techniques, especially magnetic resonance imaging (MRI), LH diagnosis has been increased. This disease usually affects young women during pregnancy or postpartum period with headache, visual impairment, ACTH deficiency and a homogenous sellar mass with thickening of pituitary stalk in MRI. Definitive diagnosis depends on histopathological evaluation; nevertheless, a presumptive diagnosis could be done in a typical case. As no specific autoantigen was identified in LH, there is no antipituitary antibody (APA) method available for helping diagnosis. However, APA used in some centers for research could support an autoimmune origin for some hypopituitarism previously named as idiopathic, confirming nuances in clinical presentation of pituitary autoimmune disease. Therapeutic approach should be based on the grade of suspicious and clinical manifestations of LH.
article 4 Citação(ões) na Scopus Primary antiphospholipid syndrome and panhypopituitarism: a unique presentation(2012) SILVA, Barbara Santos Pires da; BONIN, Camila; BUENO, Cristina Bellotti Formiga; GLEZER, Andrea; BRONSTEIN, Marcello D.; CARVALHO, Jozelio FreireLymphocytic hypophysitis (LH) has been described previously in systemic lupus erythematosus (1.3%), Sjogren's syndrome (0.8%). Lymphocytic hypo physitis (LH) is rarely associated with rheumatic diseases, although three cases of pituitary disease associated with antiphospholipid syndrome (APS) have been described. Here, we report a possible association between APS and LH for the first time. A 34-yr-old woman with primary APS presented with polyuria, polydipsia, hypernatremia and impaired vision. Her hormone profile was compatible with panhypopituitarism, and sellar magnetic resonance imaging (MRI) depicted a normal pituitary gland with a thickened and displaced stalk and infundibulum portion. Hormone replacement was started, and the patient experienced a good clinical evolution.bookPart 0 Citação(ões) na Scopus Hormonal influence in neurofibromatosis type 1-associated neurofibromas(2012) CUNHA, K. S. G.; BRONSTEIN, M.; MEZITIS, S.; GELLER, M.One of the main clinical manifestations of Neurofibromatosis type 1 (NF1) is the development of multiple neurofibromas. It has been suggested that loss of heterozygosity (LOH) of the NF1 gene in Schwann cells represents the first step in the development of NF1-associated neurofibromas. Beyond mutations of the NF1 gene, numerous additional factors probably influence neurofibroma formation and growth. Periods of hormonal changes (puberty and pregnancy) have been correlated with an increase in number and growth rate of discrete neurofibromas, and also with malignant transformation of plexiform neurofibromas. Research advances have been made in elucidating the hormonal influence in neurofibromas of NF1. Most of the studies developed to date focused on the study of steroid hormones, mainly sex steroid hormones, on the development of neurofibromas. It seems that progesterone and androgen are responsible, at least in part, for the alterations observed in neurofibromas during periods of hormonal changes. The investigations of the influence of growth hormone (GH) in neurofibromas are still in their initial steps, but it is known that the majority of NF1-associated neurofibromas express GH receptor and also insulin-like growth factor 1 (IGF-1) receptor. Current knowledge suggests that selective hormone receptor could be useful for the treatment of NF1-associated neurofibromas. © 2012 by Nova Science Publishers, Inc. All rights reserved.- Mutation and genomic amplification of the PIK3CA proto-oncogene in pituitary adenomas(2012) MURAT, C. B.; BRAGA, P. B. S.; FORTES, M. A. H. Z.; BRONSTEIN, M. D.; CORREA-GIANNELLA, M. L. C.; GIORGI, R. R.The tumorigenesis of pituitary adenomas is poorly understood. Mutations of the PIK3CA proto-oncogene, which encodes the p110-alpha catalytic subunit of PI3K, have been reported in various types of human cancers regarding the role of the gene in cell proliferation and survival through activation of the PI3K/Akt signaling pathway. Only one Chinese study described somatic mutations and amplification of the PIK3CA gene in a large series of pituitary adenomas. The aim of the present study was to determine genetic alterations of PIK3CA in a second series that consisted of 33 pituitary adenomas of different subtypes diagnosed by immunohistochemistry: 6 adrenocorticotropic hormone-secreting microadenomas, 5 growth hormone-secreting macroadenomas, 7 prolactin-secreting macroadenomas, and 15 nonfunctioning macroadenomas. Direct sequencing of exons 9 and 20 assessed by qPCR was employed to investigate the presence of mutations and genomic amplification defined as a copy number >= 4. Previously identified PIK3CA mutations (exon 20) were detected in four cases (12.1%). Interestingly, the Chinese study reported mutations only in invasive tumors, while we found a PIK3CA mutation in one noninvasive corticotroph microadenoma. PIK3CA amplification was observed in 21.2% (7/33) of the cases. This study demonstrates the presence of somatic mutations and amplifications of the PIK3CA gene in a second series of pituitary adenomas, corroborating the previously described involvement of the PI3K/Akt signaling pathway in the tumorigenic process of this gland.
- Approach to the Patient with Persistent Hyperprolactinemia and Negative Sellar Imaging(2012) GLEZER, Andrea; BRONSTEIN, Marcello D.Hyperprolactinemia is a common cause of menstrual disturbances affecting young women. There is a diversity of causes, from physiological, such as pregnancy, to pharmacological and pathological, such as hypothyroidism. Renal and hepatic failure, intercostal nerve stimulation by trauma or surgery, prolactinomas, other tumors in the hypothalamus-pituitary region, as well as macroprolactinemia can also be considered. Identifying the correct cause is important to establish the correct treatment. Should all these causes be ruled out and pituitary imaging revealed as negative, idiopathic hyperprolactinemia is therefore diagnosed. In symptomatic patients, treatment with dopaminergic agonists is indicated. As for the asymptomatic hyperprolactinemic individuals, macroprolactinemia should be screened, and once it is detected, there is no need for pituitary imaging study or for dopaminergic agonist use.
- The use of nasal dilator strips as a placebo for trials evaluating continuous positive airway pressure(2012) AMARO, Aline C. S.; DUARTE, Felipe H. G.; JALLAD, Raquel S.; BRONSTEIN, Marcello D.; REDLINE, Susan; LORENZI-FILHO, GeraldoOBJECTIVES: The aim of the current study was to compare the objective and subjective effects of continuous positive airway pressure to the use of nasal dilator strips in patients with acromegaly and moderate to severe obstructive sleep apnea. METHODS: We studied 12 patients with acromegaly and moderate to severe obstructive sleep apnea (male/females = 8/4, age = 52 +/- 8 ys, body mass index = 33.5 +/- 4.6 Kg/m(2), apnea-hypopnea index = 38 +/- 14 events/h) who had been included in a randomized, crossover study to receive three months of treatment with continuous positive airway pressure and nasal dilator strips. All patients were evaluated at study entry and at the end of each treatment by polysomnography, and Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index and treatment satisfaction questionnaires. ClinicalTrials.gov: NCT01265121 RESULTS: The apnea-hypopnea index values decreased significantly with continuous positive airway pressure treatment but did not change with the use of nasal dilator strips. All of the subjective symptoms improved with both treatments, but these improvements were significantly greater with continuous positive airway pressure than with the nasal dilator strips. CONCLUSION: The use of nasal dilator strips had a much smaller effect on the severity of obstructive sleep apnea in patients with acromegaly and moderate to severe obstructive sleep apnea in comparison to the use of continuous positive airway pressure. Moreover, the improvement in several subjective parameters without any significant objective improvement in obstructive sleep apnea resulting from the use of nasal dilator strips is compatible with a placebo effect.