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1.
J Endocrinol Invest ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38502285

RESUMO

BACKGROUND: Recurrence of acromegaly after successful surgery is a rare event, but no clear data are reported in the literature about its recurrence rates. This study aimed to evaluate the recurrence rate in a series of acromegalic patients treated by transsphenoidal surgery (TSS) with a long follow-up. METHODS: We retrospectively analyzed data from 283 acromegalic patients who underwent TSS at two pituitary units in Milan (Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico and IRCCS Humanitas Research Hospital). The diagnosis and recurrence of acromegaly were defined by both elevated IGF-1 levels and a lack of GH suppression based on appropriate criteria for the assay used at the time of diagnosis. RESULTS: After surgery, 143 patients (50%) were defined as not cured, 132 (47%) as cured and 8 (3%) as partially cured because of normalization of only one parameter, either IGF1 or GH. In the cured group, at the last follow-up (median time 86.8 months after surgery), only 1 patient (0.7%) showed full recurrence (IGF-1 + 5.61 SDS, GH nadir 1.27 µg/l), while 4 patients (3%) showed only increased IGF1. In the partially cured group at the last follow-up, 2/8 (25%) patients showed active acromegaly (IGF-1 SDS + 2.75 and + 3.62; GH nadir 0.6 and 0.5 µg/l, respectively). CONCLUSIONS: In the literature, recurrence rates range widely, from 0 to 18%. In our series, recurrence occurred in 3.7% of patients, and in fewer than 1%, recurrence occurred with elevation of both IGF-1 and the GH nadir. More frequently (25%), recurrence came in the form of incomplete normalization of either IGF-1 or GH after surgery.

2.
Radiat Environ Biophys ; 53(4): 671-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25169705

RESUMO

Characterizing the biological effects of flattening filter-free (FFF) X-ray beams from linear accelerators is of importance, due to their increasing clinical availability. The purpose of this work is to determine whether in vitro cell survival is affected by the higher dose-per-pulse present in FFF beams in comparison with flattened X-ray beams. A Varian TrueBeam(®) linear accelerator was used to irradiate the T98G, V79-4 and U87-MG cell lines with a single fraction of 5 Gy or 10 Gy doses of X-rays. Beams with energies of 6 MegaVolt (MV), 6 MV FFF and 10 MV FFF were used, with doses-per-pulse as measured at the monitor chamber of 0.28, 0.78 and 1.31 mGy/pulse for 6 MV, 6 MV FFF and 10 MV FFF, respectively. The dose delivered to each Petri dish was verified by means of ionization chamber measurements. No statistically significant effects on survival fraction were observed for any of the cell lines considered, either as a function of dose-per-pulse, average dose rate or total dose delivered. Biological effects of higher instantaneous rates should not be excluded on the basis of in vitro experimental results such as the ones presented in this work. The next step toward an assessment of the biological impact of FFF beams will require in vivo studies.


Assuntos
Doses de Radiação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Humanos , Aceleradores de Partículas , Raios X
3.
Eur Arch Otorhinolaryngol ; 270(8): 2249-53, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23292123

RESUMO

In the past decade, surgical treatment of skull base pathologies has greatly advanced through the advent of the endoscope and later of the high definition endoscope. Recently a new type of three dimensional (3D) scope has been introduced to permit the surgeon a real stereoscopic vision of the operating field and to overcome the limitations of the 2D endoscopic set up. As with all new technologies a formalized adaptation period is essential for the surgeon to secure steady outcomes and low complications. To determine the subjective difficulties that one may encounter during this sensitive period we therefore devised and analyzed a questionnaire that evaluated the first ten procedures with the 3D device of junior and senior ENT and neurosurgeons. 52 consecutive patients were treated with purely 3D transnasal endoscopy for skull base pathologies. Sensation of strain or dizziness, difficulties in anatomical orientation and difficulties in performing the surgical gesture were assessed for each surgeon. The learning curve and difficulties of junior and senior surgeons are discussed and strategies to overcome the initial problems are devised. Our results confirm that after only few procedures, the advantages of the 3D endoscopic system including better visualization and depth perception are able to outweigh the inconveniences that go hand in hand with the learning of a new skill set.


Assuntos
Endoscópios , Endoscopia/educação , Imageamento Tridimensional/métodos , Neurocirurgia/educação , Otolaringologia/educação , Base do Crânio/cirurgia , Adulto , Idoso , Endoscopia/instrumentação , Endoscopia/métodos , Desenho de Equipamento , Feminino , Humanos , Curva de Aprendizado , Masculino , Pessoa de Meia-Idade , Neurocirurgia/instrumentação , Otolaringologia/instrumentação , Inquéritos e Questionários
4.
Endocrine ; 72(3): 915-922, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33242176

RESUMO

PURPOSE: The management of pituitary adenomas in the elderly has become a relevant clinical issue, in relationship with improved life expectancy and spreading use of imaging techniques. In this single-center and retrospective study, we investigated the impact of age on peri- and postsurgical outcomes in patients undergoing transnasal sphenoidal (TNS) surgery for pituitary adenomas. METHODS: One-hundred-sixty-nine patients (62% males) undergoing endoscopic transphenoidal (TNS) surgery for nonfunctioning pituitary adenomas (NFPAs) were enrolled. Patients were subdivided into three groups according to age tertiles: ≤56 (group 1), 57-69 (group 2), and ≥70 (group 3) years. Postsurgical and endocrinological outcomes were evaluated and compared among the three age groups. RESULTS: 37/169 patients (21.9%) developed at least one perisurgical complication, without significant association with the patients' age (P = 0.838), Charlson co-morbidity score (P = 0.326), and American Society of Anesthesiologist score (P = 0.616). In the multivariate regression analysis, the adenoma size resulted the only determinant of perisurgical complication (odds ratio [OR] 1.07, 95% confidence interval [C.I.] 1.00-1.13; P = 0.044). The development and the recovery of at least one pituitary hormone deficiency were observed in 12.2% and 14.2% of patients, respectively. The risk of developing new pituitary hormone deficiencies was correlated with cavernous sinus invasion as evaluated by magnetic resonance imaging (hazard ratio [HR] 4.19, 95% C.I. 1.39-12.66; P = 0.010), whereas the probability to normalize at least one pituitary hormone deficiency was significantly correlated with younger age of patients (HR 0.27, 95% CI 0.12-0.61; P = 0.002). CONCLUSIONS: The results of this study reinforce the concept that endoscopic TNS surgery is a safe therapeutic option in the elderly patients with NFPA, even in presence of comorbidities and high anesthetic risk.


Assuntos
Adenoma , Hipopituitarismo , Neoplasias Hipofisárias , Adenoma/cirurgia , Idoso , Pré-Escolar , Endoscopia , Feminino , Humanos , Hipopituitarismo/epidemiologia , Hipopituitarismo/etiologia , Masculino , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
5.
Phys Med Biol ; 66(4): 045035, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33207334

RESUMO

Many surrogate-based motion models (SMMs), proposed to guide motion management in radiotherapy, are constructed by correlating motion of an external surrogate and internal anatomy during CT-simulation. Changes in this correlation define model break down. We validate a methodology that incorporates fluoroscopic (FL) images acquired during treatment for SMM construction and update. Under a prospective IRB, 4DCT scans, VisionRT (VRT) surfaces, and orthogonal FLs were collected from five lung cancer patients. VRT surfaces and two FL time-series were acquired pre- and post-treatment. A simulated annealing optimization scheme was used to estimate optimal lung deformations by maximizing the mutual information (MI) between digitally reconstructed radiographs (DRRs) of the SMM-estimated 3D images and FLs. Our SMM used partial-least-regression and was trained using the optimal deformations and VRT surfaces from the first breathing-cycle. SMM performance was evaluated using the MI score between reference FLs and the corresponding SMM or phase-assigned 4DCT DRRs. The Hausdorff distance for contoured landmarks was used to evaluate target position estimation error. For four out of five patients, two principal components approximated lung surface deformations with submillimeter accuracy. Analysis of the MI score between more than 4000 pairs of FL and DRR demonstrated that our model led to more similarity between the FL and DRR images compared to 4DCT and DRR images from a model based on an a priori correlation model. Our SMM consistently displayed lower mean and 95th percentile Hausdorff distances. For one patient, 95th percentile Hausdorff distance was reduced by 11 mm. Patient-averaged reductions in mean and 95th percentile Hausdorff distances were 3.6 mm and 7 mm for right-lung, and 3.1 mm and 4 mm for left-lung targets. FL data were used to evaluate model performance and investigate the feasibility of model update. Despite variability in breathing, use of post-treatment FL preserved model fidelity and consistently outperformed 4DCT for position estimation.


Assuntos
Fluoroscopia , Tomografia Computadorizada Quadridimensional , Pulmão/diagnóstico por imagem , Pulmão/fisiologia , Modelos Biológicos , Movimento , Humanos , Respiração
6.
J Endocrinol Invest ; 32(5): 460-4, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19494715

RESUMO

BACKGROUND: Peri-operative steroids are administered routinely to patients with pituitary adenoma undergoing transsphenoidal adenomectomy (TSA). AIM: To evaluate hypothalamic-pituitary-adrenal (HPA) axis before and after programmed endoscopic TSA (E-TSA) in patients with clinically non-functioning pituitary macroadenoma (NFPA). DESIGN: Open prospective. SETTING: Tertiary referral hospitals. PATIENTS: Seventy-two consecutive patients (20-87 yr, 37 males). INTERVENTIONS: Adrenal steroid replacement therapy (ASRT) was given only in patients with hypocortisolism [08:00 h cortisol (F) <8 microg/dl]. MAIN OUTCOME MEASUREMENTS: After ETSA, achieving wide (>90%) selective resection of the adenoma in all, F and clinical picture were checked at day 2. The low-dose (1 microg) ACTH test (LDACTH) was performed at 6 weeks and repeated at 12 months. RESULTS: Hypocortisolism was present pre-operatively in 14 patients (19.4%), persisted post-operatively in all but one, and was detected de novo at the post-operative day 2 control in 6 (10.3%). In all but one the post-operative day 2 basal F and peak F during LDACTH test were concordant. No patient whose F was > 8 microg/dl was treated with ASRT or developed symptoms of adrenal failure during the follow-up (1-11 yr, median 5). CONCLUSIONS: HPA function is usually preserved in NFPA and is infrequently impaired after complete tumor removal by E-TSA. The 08:00 h. plasma cortisol evaluation before and 2 days after surgery, using as cut-off the value of 8 microg/dl, allows full evaluation of HPA status. Peri-operative steroid treatment should be given only in patients with hypocortisolism.


Assuntos
Adenoma/diagnóstico , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/fisiopatologia , Neoplasias Hipofisárias/diagnóstico , Sistema Hipófise-Suprarrenal/fisiopatologia , Adenoma/sangue , Adenoma/fisiopatologia , Adenoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/sangue , Neoplasias Hipofisárias/fisiopatologia , Neoplasias Hipofisárias/cirurgia , Complicações Pós-Operatórias/diagnóstico , Período Pós-Operatório , Período Pré-Operatório , Prognóstico , Adulto Jovem
7.
Med Phys ; 46(12): 5407-5420, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31518437

RESUMO

PURPOSE: We develop and validate a motion model that uses real-time surface photogrammetry acquired concurrently with four-dimensional computed tomography (4DCT) to estimate respiration-induced changes within the entire irradiated volume, over arbitrarily many respiratory cycles. METHODS: A research, couch-mounted, VisionRT (VRT) system was used to acquire optical surface data (15 Hz, ROI = 15 × 20 cm2 ) from the thoraco-abdominal surface of a consented lung SBRT patient, concurrently with their standard-of-care 4DCT. The end-exhalation phase from the 4DCT was regarded as reference and for each remaining phase, deformation vector fields (DVFs) with respect to the reference phase were computed. To reduce dimensionality, the first two principal components (PCs) of the matrix of nine DVFs were calculated. In parallel, ten phase-averaged VRT surfaces were created. Surface DVFs and corresponding PCs were computed. A principal least squares regression was used to relate the PCs of surface DVF to those of volume DVFs, establishing a relationship between time-varying surface and the underlying time-varying volume. Proof-of-concept validation was performed during each treatment fraction by concurrently acquiring 30 s time series of real-time surface data and "ground truth" kV fluoroscopic data (FL). A ray-tracing algorithm was used to create a digitally reconstructed fluorograph (DRF), and motion trajectories of high-contrast, soft-tissue, anatomical features in the DRF were compared with those from kV FL. RESULTS: For five of the six fluoroscopic acquisition sessions, the model out-performed 4DCT in predicting contour Dice coefficient with respect to fluoroscopy-derived contours. Similarly, the model exhibited a marked improvement over 4DCT for patch positions on the diaphragm. Model patch position errors varied from 5 to -15 mm while 4DCT errors ranged between 5 and -22.4 mm. For one fluoroscopic acquisition, a marked change in the a priori internal-external correlation resulted in model errors comparable to those of 4DCT. CONCLUSIONS: We described the development and a proof-of-concept validation for a volumetric motion model that uses surface photogrammetry to correlate the time-varying thoraco-abdominal surface to the time-varying internal thoraco-abdominal volume. These early results indicate that the proposed approach can result in a marked improvement over 4DCT. While limited by the duration of the fluoroscopic acquisitions as well as the resolution of the acquired images, the DRF-based proof-of-concept technique developed here is model-agnostic, and therefore, has the potential to be used as an in-patient validation tool for other volumetric motion models.


Assuntos
Tomografia Computadorizada Quadridimensional , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Modelos Biológicos , Movimento , Fotogrametria , Idoso , Fracionamento da Dose de Radiação , Humanos , Neoplasias Pulmonares/fisiopatologia , Masculino , Respiração , Fatores de Tempo
8.
J Neurol ; 232(5): 277-9, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4056834

RESUMO

Forty-nine patients who suffered a spontaneous subarachnoid hemorrhage (SAH), and in whom panangiography did not show the cause of the bleeding, were evaluated after a long follow-up (median 8 years). No relationship was found between outcome and antifibrinolytic treatment or blood pressure level. Angiography was repeated in cases with spasm or after rebleeding: one aneurysm was found (7%). The authors suggest that angiography should be repeated in these circumstances. The early mortality was 2%. Late functional capacity was normal in 94% of the patients. No particular restrictions should therefore be recommended.


Assuntos
Hemorragia Subaracnóidea/diagnóstico , Adulto , Idoso , Ácido Aminocaproico/efeitos adversos , Angiografia Cerebral , Feminino , Seguimentos , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/terapia
9.
Neurosurgery ; 26(5): 783-6; discussion 786-7, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2352596

RESUMO

Long-term results (average follow-up, 9.3 years) obtained in 1000 consecutive patients suffering from cryptogenetic ("essential") trigeminal neuralgia treated with percutaneous thermorhizotomy are analyzed. Pain relief was obtained in 95% of the treated patients. Permanent morbidity was as follows: masseter weakness in 105 patients; oculomotor palsies in 5 patients; weakening of the corneal reflex in 197 patients, 6 of whom requested an ocular operation for keratitis; and painful dysesthesia in 52 patients, 15 of whom developed a painful anesthesia syndrome. There was a recurrence rate of 18.1%, and a correlation between postoperative sensory deficit and the cure rate was found. These results are discussed and compared to the results obtained with different techniques.


Assuntos
Eletrocoagulação , Ondas de Rádio , Neuralgia do Trigêmeo/cirurgia , Idoso , Idoso de 80 Anos ou mais , Denervação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Raízes Nervosas Espinhais/cirurgia , Gânglio Trigeminal/cirurgia , Nervo Trigêmeo/cirurgia
10.
Neurosurgery ; 25(2): 153-60, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2671779

RESUMO

The long-term results obtained in a series of 174 patients operated on for spinal meningiomas are critically analyzed. This series was similar to those of other authors with regard to age, sex, location of the tumors, and clinical presentation. Before surgery, about 70% of the patients were included in Groups I and II (mild neurological impairment), and about 30% of the patients were classified in Groups III and IV (significant to severe neurological impairment, up to paraplegia). Complete tumor removal was achieved in 96.5% of the patients, and surgical mortality was about 1%. Microsurgical technique, which was adopted in the last 29 cases, proved to be very effective in reducing undue damage to the spinal cord and in minimizing the postoperative neurological deficits. Of the 174 patients who underwent surgery, 156 underwent late follow-up study for an average of 15 years (2 patients died in the immediate postoperative period, and 16 patients were lost to follow-up). Twenty-nine patients died of causes unrelated to the spinal meningioma; of the remaining 126 patients, 92% were categorized in Groups I and II, and only 8% in Groups III and IV. The rate of recurrence was 6% (9 patients) among the 150 patients who had complete tumor removal, and the rate of regrowth was 17% (1 patient with anaplastic meningioma) among the 6 patients treated by subtotal removal. The early diagnosis of the disease and the use of microsurgical technique appeared as the most relevant factors for further improvement of the surgical results.


Assuntos
Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Neoplasias da Medula Espinal/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Laminectomia , Imageamento por Ressonância Magnética , Masculino , Neoplasias Meníngeas/patologia , Meningioma/patologia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Complicações Pós-Operatórias , Neoplasias da Medula Espinal/patologia
11.
J Neurosurg Sci ; 35(4): 179-85, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1812242

RESUMO

A surgical series of 59 patients with cerebellar or spinal cord hemangioblastomas or von Hippel-Lindau's (VHL) syndrome is analyzed. The presence of the tumor is easily detected by Computerized Tomography (CT) and Nuclear Magnetic Resonance (NMR), but angiography is still necessary for a correct surgical planning. The value of a sharp distinction among patients with single hemangioblastomas and the ones with Lindau's disease and VHL syndrome is stressed. In fact patients with single cerebellar or spinal hemangioblastomas have a good prognosis, while patients with disseminated hemangioblastomas have a rather poor outlook. Neuropathological studies with immunohistochemical techniques have been performed to identify the nature of the stromal cells of the hemangioblastomas: their origin from glial, endothelial and monociticphagocitic elements seems excluded.


Assuntos
Neoplasias Cerebelares/fisiopatologia , Neoplasias Cerebelares/cirurgia , Hemangiossarcoma/fisiopatologia , Hemangiossarcoma/cirurgia , Neoplasias da Medula Espinal/fisiopatologia , Neoplasias da Medula Espinal/cirurgia , Doença de von Hippel-Lindau/cirurgia , Adolescente , Adulto , Idoso , Neoplasias Cerebelares/patologia , Criança , Diagnóstico Diferencial , Feminino , Seguimentos , Proteína Glial Fibrilar Ácida/análise , Hemangiossarcoma/patologia , Humanos , Imuno-Histoquímica , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Muramidase/análise , Estudos Retrospectivos , Neoplasias da Medula Espinal/patologia , Vimentina/análise , alfa 1-Antiquimotripsina/análise , alfa 1-Antitripsina/análise , Doença de von Hippel-Lindau/patologia , Doença de von Hippel-Lindau/fisiopatologia , Fator de von Willebrand/análise
12.
J Neurosurg Sci ; 45(4): 216-9; discussion 219, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11912473

RESUMO

Pigmented villonodular synovitis (PVNS) is a disease of the joints which uncommonly involves the spine. We present a 70-year-old woman with radicular symptoms who was found to have a mass arising from a lumbar zygapophyseal joint with extension into the spinal canal. Following gross-total excision of the mass, histology revealed PVNS. One month after surgery, the patient had no symptoms and there was no evidence of residual or recurrent disease.


Assuntos
Vértebras Lombares/diagnóstico por imagem , Doenças da Coluna Vertebral/diagnóstico por imagem , Doenças da Coluna Vertebral/patologia , Sinovite Pigmentada Vilonodular/diagnóstico por imagem , Sinovite Pigmentada Vilonodular/patologia , Idoso , Descompressão Cirúrgica , Feminino , Humanos , Laminectomia , Perna (Membro) , Vértebras Lombares/cirurgia , Dor/etiologia , Radiografia , Doenças da Coluna Vertebral/cirurgia , Sinovite Pigmentada Vilonodular/complicações , Sinovite Pigmentada Vilonodular/cirurgia
13.
Surg Neurol ; 26(6): 581-4, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3490704

RESUMO

A patient harboring multiple hereditary exostoses with a long-lasting tetraparesis owing to intraspinal osteochondroma is described. The results of surgical treatment were poor in contrast to the results achieved by other previous authors performing decompression of the spinal cord. The related literature is briefly reviewed and conclusions are drawn in favor of computed tomographic examination of the spine of patients with vertebral complaints.


Assuntos
Exostose Múltipla Hereditária/complicações , Compressão da Medula Espinal/etiologia , Doenças da Coluna Vertebral/complicações , Adulto , Condroma/complicações , Humanos , Masculino , Neoplasias da Coluna Vertebral/complicações
14.
Surg Neurol ; 21(5): 427-35, 1984 May.
Artigo em Inglês | MEDLINE | ID: mdl-6710323

RESUMO

The immediate results of surgery--for the most part radical surgery--in 342 cases of parasagittal and falx meningiomas are presented. The late outcome in 317 survivors observed for at least five years and possible ways of avoiding them are discussed with special reference to recurrences and disabling sequels.


Assuntos
Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/cirurgia
15.
Endocrinology ; 155(8): 2932-41, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24828612

RESUMO

Somatostatin receptor type 2 (SST2) is the main pharmacological target of medical therapy for GH-secreting pituitary tumors, but molecular mechanisms regulating its expression and signaling are largely unknown. The aim of this study was to investigate the role of cytoskeleton protein filamin A (FLNA) in SST2 expression and signaling in somatotroph tumor cells. We found a highly variable expression of FLNA in human GH-secreting tumors, without a correlation with SST2 levels. FLNA silencing in human tumoral cells did not affect SST2 expression and localization but abolished the SST2-induced reduction of cyclin D1 (-37% ± 15% in control cells, P < .05 vs basal) and caspase-3/7 activation (+63% ± 31% in control cells, P < .05 vs basal). Overexpression of a FLNA dominant-negative mutant that specifically prevents SST2-FLNA binding reduced SST2 expression after prolonged agonist exposure (-55% ± 5%, P < .01 vs untreated cells) in GH3 cells. Moreover, SST2-induced apoptotic effect (77% ± 54% increase of caspase activity, P < .05 vs basal) and SST2-mediated ERK1/2 inhibition (48% ± 17% reduction of ERK1/2 phosphorylation, P < .01 vs basal) were abrogated in cells overexpressing another FLNA mutant that prevents FLNA interaction with partner proteins but not with SST2, suggesting a scaffold function of FLNA in somatotrophs. In conclusion, these data demonstrate that FLNA is involved in SST2 stabilization and signaling in tumoral somatotrophs, playing both a structural and functional role.


Assuntos
Filaminas/fisiologia , Receptores de Somatostatina/fisiologia , Transdução de Sinais/fisiologia , Somatotrofos/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Estabilidade Proteica , Ratos , Receptores de Somatostatina/agonistas
16.
Mol Cell Endocrinol ; 383(1-2): 193-202, 2014 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-24373949

RESUMO

In the pituitary the activation of cyclic adenosine 3'-5'-monophosphate (cAMP) dependent pathways generates proliferative signals in somatotrophs, whereas in pituitary cells of other lineages its effect remains uncertain. Moreover, the specific role of the two main cAMP effectors, protein kinase A (PKA) and exchange proteins directly activated by cAMP (Epac), has not been defined. Aim of this study was to investigate the effect of cAMP on pituitary adenomatous cells proliferation and to identify PKA and Epac differential involvement. We found that cAMP increased DNA synthesis and cyclin D1 expression in somatotropinomas, whereas it reduced both parameters in prolactinomas and nonfunctioning adenomas, these effects being replicated in corresponding cell lines. Moreover, the divergent cAMP effects were mimicked by Epac and PKA analogs, which activated Rap1 and CREB, respectively. In conclusion, we demonstrated that cAMP exerted opposite effects on different pituitary cell types proliferation, these effects being mediated by both Epac and PKA.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/genética , AMP Cíclico/metabolismo , Regulação Neoplásica da Expressão Gênica , Fatores de Troca do Nucleotídeo Guanina/genética , Hipófise/metabolismo , Subunidades Proteicas/genética , Adenoma/genética , Adenoma/metabolismo , Adenoma/patologia , Animais , Proliferação de Células , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Gonadotrofos/metabolismo , Gonadotrofos/patologia , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Lactotrofos/metabolismo , Lactotrofos/patologia , Hipófise/patologia , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Prolactinoma/genética , Prolactinoma/metabolismo , Prolactinoma/patologia , Subunidades Proteicas/metabolismo , Ratos , Transdução de Sinais , Somatotrofos/metabolismo , Somatotrofos/patologia , Proteínas rap1 de Ligação ao GTP/genética , Proteínas rap1 de Ligação ao GTP/metabolismo
17.
Acta Otorhinolaryngol Ital ; 33(2): 102-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23853400

RESUMO

The recent introduction of the 3D endoscope for endonasal surgery has been welcomed because of its promise to overcome the main limitation of endoscopy, namely the lack of stereoscopic vision. This innovation particularly regarded the most complex transnasal surgery of the skull base. We therefore discuss our early experience as ENT surgeons with the use of a purely 3D endoscopic expanded endonasal approach for supradiaphragmatic lesions in 10 consecutive patients. This article will focus on the surgical technique, the complications, the outcome, and more importantly the advantages and limitations of the new device. We believe that the new 3D system shows its main drawback when surgery is conducted in the narrow nasal spaces. Nevertheless, the improved knowledge of the three-dimensional nasal anatomy enabled the ENT surgeon to perform a more selective demolition of the nasal structures even in the anterior part of the nose. The depth perception obtained with the 3D system also permitted a better understanding of the plasticity of the surgical defects, increasing the confidence to perform successful skull base plasties. We believe that, for both the ENT surgeon and the neurosurgeon, the expanded endonasal approach is the main indication for this exciting tool, although larger prospective studies are needed to determine the equality to the 2D HD endoscope in oncological terms.


Assuntos
Endoscópios , Endoscopia , Imageamento Tridimensional , Procedimentos Cirúrgicos Nasais/instrumentação , Procedimentos Cirúrgicos Nasais/métodos , Base do Crânio/cirurgia , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nariz , Estudos Retrospectivos
18.
J Neuroendocrinol ; 23(12): 1214-21, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21883533

RESUMO

Patients with Cushing's disease are known to present a variable secretory response to stimulatory and inhibitory challenges. Evaluation of the secretory behaviour of pituitary adrenocorticotrophic hormone (ACTH)-secreting adenomas in vitro aids in the comprehension of its behaviour in vivo; however, given the small size of these tumours and the consequent paucity of material available to in vitro studies, a comprehensive study on the secretory behaviour of human corticotroph tumours has not yet been performed. The present study aimed to assess the spectrum of responses to the two main corticotroph modulators, corticotrophin-releasing hormone (CRH) and dexamethasone, in a large series of human ACTH-secreting pituitary tumours. Seventy-two ACTH-secreting pituitary tumours were collected during surgery and established in culture. Specimens were incubated with 10 nm CRH and/or 10 nm dexamethasone for 4 h and 24 h. Secretion in unstimulated, control wells was set at 100% and changes in ACTH concentrations by at least 20% were considered as responses. Parallel experiments in 12 rat anterior pituitary primary cultures were evaluated. A marked ACTH increase was observed during incubation with CRH in 70% of tumoural specimens at 4 h (range 124-3500% of control wells) and in 57% at 24 h (range 122-3323%). Dexamethasone reduced ACTH secretion in almost 50% of tumours (range 78-2% of control at 4 h; 76-3% at 24 h), whereas it did not affect ACTH medium levels in 30% of specimens and induced a paradoxical ACTH increase in 20% of tumours (range 130-327% of control at 4 h; 156-348% at 24 h). By comparison, CRH uniformly increased ACTH levels in rat anterior pituitary primary cultures (mean 745 ± 84% at 4 h; 347 ± 25% at 24 h), whereas dexamethasone decreased ACTH levels by 40-50% in all experiments. In conclusion, the present study of a large series of human ACTH-secreting pituitary tumours in vitro revealed a considerable variability in the responses to CRH and dexamethasone. This finding indicates the existence of multiple corticotroph tumoural phenotypes and may account for the different responses to physiological and pharmacological modulators in vivo.


Assuntos
Adenoma Hipofisário Secretor de ACT/metabolismo , Adenoma/metabolismo , Hormônio Liberador da Corticotropina/farmacologia , Dexametasona/farmacologia , Adenoma Hipofisário Secretor de ACT/patologia , Adenoma/patologia , Hormônio Adrenocorticotrópico/metabolismo , Animais , Estudos de Coortes , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Masculino , Fenótipo , Ratos , Estudos Retrospectivos , Fatores de Tempo , Carga Tumoral , Células Tumorais Cultivadas
19.
J Neuroendocrinol ; 22(4): 294-300, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20136686

RESUMO

Prepro-thyrotrophin-releasing hormone (TRH) (178-199), a 22-amino acid cleavage product of the TRH prohormone, has been postulated to act as an adrenocorticotrophin hormone (ACTH)-release inhibitor. Indeed, although in vitro evidence indicates that this peptide may inhibit basal and stimulated ACTH secretion in rodent anterior pituitary primary cultures and cell lines, not all studies concur and no study has as yet evaluated the effect of this peptide in Cushing's disease. The present study aimed to test the effect of preproTRH(178-199) in human tumoural corticotrophs. Twenty-four human ACTH-secreting pituitary tumours (13 macroadenomas, 11 microadenomas) were collected during surgery and incubated with 10 or 100 nm preproTRH(178-199). ACTH secretion was assessed after 4 and 24 h of incubation by immunometric assay and expressed relative to levels observed in control, unchallenged wells (= 100%). Parallel experiments were performed in rat anterior pituitary primary cultures. A clear inhibition of ACTH secretion at 4 and 24 h was observed in 12 specimens (for 10 nm ppTRH: 70 +/- 4% control at 4 h and 83 +/- 5% control at 24 h; for 100 nm ppTRH: 70 +/- 4% control at 4 h and 85 +/- 5% control at 24 h), whereas a mild and short-lasting stimulatory effect was observed in three tumours and no changes in ACTH secretion in the remaining nine tumoural specimens. The inhibitory effect of preproTRH(178-199) was more evident in macroadenomas and significantly correlated with sensitivity to dexamethasone inhibition. Significant inhibition of ACTH secretion by preproTRH(178-199) in rat pituitary cultures was observed after 24 h of incubation. The present study conducted in a large series of human corticotroph tumours shows that preproTRH(178-199) inhibits tumoural ACTH secretion in a sizable proportion of specimens, in close relation to the size of the tumour and its sensitivity to glucocorticoid negative feedback. This appears a promising avenue of research and further studies are warranted to explore the full scope of preproTRH(178-199) as a regulator of ACTH secretion.


Assuntos
Adenoma Hipofisário Secretor de ACT/metabolismo , Adenoma/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , Fragmentos de Peptídeos/farmacologia , Precursores de Proteínas/farmacologia , Hormônio Liberador de Tireotropina/farmacologia , Adenoma Hipofisário Secretor de ACT/patologia , Adenoma/patologia , Animais , Técnicas de Cultura de Células , Células Cultivadas , Hormônio Liberador da Corticotropina/farmacologia , Dexametasona/farmacologia , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Antagonistas de Hormônios/farmacologia , Humanos , Masculino , Adeno-Hipófise/efeitos dos fármacos , Adeno-Hipófise/metabolismo , Ratos
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