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1.
J Endocrinol Invest ; 47(7): 1751-1762, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38386266

RESUMEN

BACKGROUND: Limited information exists on postoperative hypocortisolism and hypothalamus-pituitary-adrenal axis recovery in patients with adrenal incidentaloma following unilateral adrenalectomy. We evaluated frequency of postoperative hypocortisolism and predictors for recovery in non-aldosterone-producing adrenocortical adenoma patients after unilateral adrenalectomy. METHODS: A retrospective analysis of 32 adrenal incidentaloma patients originally included in the ITACA trial (NCT04127552) with confirmed non-aldosterone-producing adrenocortical adenoma undergoing unilateral adrenalectomy from September 2019 to April 2023 was conducted. Preoperative assessments included adrenal MRI, anthropometrics, evaluation of comorbidities, adrenal function assessed via ACTH, urinary free cortisol, and 1 mg dexamethasone suppression test. ACTH and serum cortisol or Short Synacthen test were performed within 6 days, 6 weeks, 6 months, and a year after surgery. RESULTS: Six days postoperative, 18.8% of patients had normal adrenal function. Among those with postoperative hypocortisolism, 53.8% recovered by 6 weeks. Patients with earlier adrenal recovery (6 weeks) had lower preoperative 1 mg dexamethasone suppression test (median 1 mg dexamethasone suppression test 76.2 [61.8-111.0] nmol/L vs 260.0 [113.0-288.5] nmol/L, p < 0.001). Univariate analysis showed preoperative 1 mg dexamethasone suppression test negatively related with baseline ACTH levels (r = - 0.376; p = 0.041) and negatively associated with the 6-week baseline (r = - 0.395, p = 0.034) and 30-min cortisol levels during Short Synacthen test (r = - 0.534, p = 0.023). Logistic regression analysis demonstrated preoperative 1 mg dexamethasone suppression test as the only biochemical predictor for 6-week adrenal recovery: ROC curve identified a 1 mg dexamethasone suppression test threshold of 131 nmol/L predicting 6-week recovery with 89.5% sensitivity and 72.7% specificity (AUC 0.87; 95% CI 66.9-98.7, p < 0.001). Other preoperative assessments (tumor size, ACTH levels and anthropometrics) were not associated with postoperative hypothalamus-pituitary-adrenal axis function, but the presence of diabetes was associated with a lower probability of recovery (OR = 24.55, p = 0.036). ACTH levels increased postoperatively in all patients but did not predict hypothalamus-pituitary-adrenal axis recovery. CONCLUSIONS: The preoperative 1 mg dexamethasone suppression test cortisol value and presence of diabetes are the only relevant predictor of hypothalamus-pituitary-adrenal axis recovery in patients with non-aldosterone- producing adrenocortical adenoma undergoing surgery, regardless other clinical and biochemical variables. Notably, pre- and postoperative ACTH levels did not predict hypothalamus-pituitary-adrenal axis recovery. These findings point towards the potential for saving resources by optimizing their allocation during follow-up assessments for patients with non-aldosterone-producing adrenocortical adenoma undergoing unilateral adrenalectomy.


Asunto(s)
Adrenalectomía , Adenoma Corticosuprarrenal , Hidrocortisona , Complicaciones Posoperatorias , Humanos , Femenino , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Hidrocortisona/sangre , Adenoma Corticosuprarrenal/cirugía , Adenoma Corticosuprarrenal/sangre , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/sangre , Anciano , Neoplasias de la Corteza Suprarrenal/cirugía , Neoplasias de la Corteza Suprarrenal/sangre , Sistema Hipófiso-Suprarrenal/metabolismo , Sistema Hipotálamo-Hipofisario/metabolismo , Pronóstico , Adulto , Hormona Adrenocorticotrópica/sangre , Estudios de Seguimiento , Dexametasona , Neoplasias de las Glándulas Suprarrenales
2.
J Physiol Pharmacol ; 70(4)2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31741459

RESUMEN

Umbilical vessels have a low sensitivity to dilate, and this property is speculated to have physiological implications. We aimed to investigate the different relaxing responses of human umbilical arteries (HUAs) and veins (HUVs) to agonists acting through the cAMP and cGMP pathways. Vascular rings were suspended in organ baths for isometric force measurement. Following precontraction with the thromboxane prostanoid (TP) receptor agonist U44069, concentration-response curves to the nitric oxide (NO) donor sodium nitroprusside (SNP), the soluble guanylate cyclase (sGC) stimulator BAY 41-2272, the adenylate cyclase (AC) activator forskolin, the ß-adrenergic receptor agonists isoproterenol (ADRB1), salmeterol (ADRB2), and BRL37344 (ADRB3), and the phosphodiesterase (PDE) inhibitors milrinone (PDE3), rolipram (PDE4), and sildenafil (PDE5) were performed. None of the tested drugs induced a relaxation higher than 30% of the U44069-induced tone. Rings from HUAs and HUVs showed a similar relaxation to forskolin, SNP, PDE inhibitors, and ADRB agonists. BAY 41-2272 was significantly more efficient in relaxing veins than arteries. ADRB agonists evoked weak relaxations (< 20%), which were impaired in endothelium-removed vessels or in the presence of the NO synthase inhibitor L-NAME, sGC inhibitor ODQ. PKA and PKG inhibitors impaired ADBR1-mediated relaxation but did not affect ADRB2-mediated relaxation. ADRB3-mediated relaxation was impaired by PKG inhibition in HUAs and by PKA inhibition in HUVs. Although HUA and HUV rings were relaxed by BRL37344, immunohistochemistry and RT-qPCR analysis showed that, compared to ADRB1 and ADRB2, ADRB3 receptors are weakly or not expressed in umbilical vessels. In conclusion, our study confirmed the low relaxing capacity of HUAs and HUVs from term infants. ADRB-induced relaxation is partially mediated by endothelium-derived NO pathway in human umbilical vessels.


Asunto(s)
AMP Cíclico/fisiología , GMP Cíclico/fisiología , Arterias Umbilicales/fisiología , Venas Umbilicales/fisiología , Vasodilatación/fisiología , Células Cultivadas , Células Endoteliales/fisiología , Humanos , Recién Nacido , Receptores Adrenérgicos beta/fisiología , Arterias Umbilicales/efectos de los fármacos , Venas Umbilicales/efectos de los fármacos , Vasoconstrictores/farmacología , Vasodilatación/efectos de los fármacos , Vasodilatadores/farmacología
3.
J Microsc ; 270(2): 210-216, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29323729

RESUMEN

We propose an innovative experimental approach to estimate the two-photon absorption (TPA) spectrum of a fluorescent material. Our method develops the standard indirect fluorescence-based method for the TPA measurement by employing a line-shaped excitation beam, generating a line-shaped fluorescence emission. Such a configuration, which requires a relatively high amount of optical power, permits to have a greatly increased fluorescence signal, thus avoiding the photon counterdetection devices usually used in these measurements, and allowing to employ detectors such as charge-coupled device (CCD) cameras. The method is finally tested on a fluorescent isothiocyanate sample, whose TPA spectrum, which is measured with the proposed technique, is compared with the TPA spectra reported in the literature, confirming the validity of our experimental approach.

4.
Rev Sci Instrum ; 85(2): 02B908, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24593613

RESUMEN

SPES (Selective Production of Exotic Species) is an Isotope Separation On-Line (ISOL) based accelerator facility that will be built in the Legnaro-Istituto Nazionale di Fisica Nucleare (INFN) Laboratory (Italy), intended to provide intense neutron-rich radioactive ion beams obtained by proton-induced fission of a uranium carbide (UCx) target. Besides this main target material, silicon carbide (SiC) will be the first to be used to deliver p-rich beams. This target will also validate the functionality of the SPES facility with aluminum beam as result of impinging SiC target with proton beam. In the past, off line studies on laser photoionization of aluminum have been performed in Pavia Spectroscopy Laboratory and in Laboratori Nazionali di Legnaro; a XeCl excimer laser was installed in order to test the laser ionization in the SPES hot cavity. With the new Wien filter installed a better characterization of the ionization process in terms of efficiency was performed and results are discussed.

5.
Rev Sci Instrum ; 83(2): 02B317, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22380296

RESUMEN

Selective production of exotic species (SPES) is an ISOL-based accelerator facility that will be built in the Legnaro INFN Laboratory (Italy), intended to provide an intense neutron-rich radioactive ion beams obtained by proton induced fission of an uranium carbide target. Beside this main target, a silicon carbide (SiC) target will the first to be used to deliver some p-rich beams. This target will validate also the functionality of the SPES facility with aluminum beam as result of hitting SiC target with protons. In the past off-line studies on laser photoionization of aluminum have performed in Pavia Spectroscopy Laboratory and in Laboratori Nazionali di Legnaro where, recently, a XeCl excimer laser was installed in order to test the laser ionization in the SPES hot cavity. Results are promising to justify further studies with this technique, aiming a better characterization of the SPES ion extraction capability under laser photoionization.

7.
Am J Cardiol ; 88(2): 101-6, 2001 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-11448403

RESUMEN

Technetium-99m (Tc-99m)-tetrofosmin is a radio isotope that has been shown to be an accurate alternative to thallium-201 for detecting coronary artery disease. However, its prognostic value is less well determined. To this end, 459 consecutive patients (mean age 58 +/- 10 years) with suspected or known coronary artery disease underwent exercise single-photon emission tomography Tc-99m-tetrofosmin scintigraphy. Follow-up, defined as the time from scanning until a soft event (revascularization procedures), a hard event (myocardial infarction and cardiac death), or patient response, lasted up to 78 months (median 38). An ischemic scintigraphic perfusion score, which takes into account both the extent and severity of reversible perfusion defects, was calculated to estimate the severity of perfusion abnormalities. Patients with normal scans were at low risk of events (yearly hard event rate 0.5% and soft event rate 0.9%). The rate of outcomes increased significantly with abnormal scans (yearly hard event rate 4.9% and soft event rate 10.3%). Statistical analysis using the Kaplan-Meyer survival curves showed a significant difference in event-free survival between patients with normal and abnormal scans. With use of Cox proportional-hazards analysis, after adjusting for prescan information, nuclear data provided incremental prognostic value for hard events (clinical and exercise data vs nuclear data; chi-square = 15.5 vs 33.4, p <0.001). Exercise single-photon emission tomographic scintigraphy using Tc-99m-tetrofosmin provides significant independent information on the subsequent risk of hard and soft events. The annual event rate for hard and soft events is <1% for patients with a normal scan. Furthermore, this tracer yields incremental prognostic information in addition to that provided by clinical and exercise data for hard events.


Asunto(s)
Enfermedad Coronaria/diagnóstico por imagen , Compuestos Organofosforados , Compuestos de Organotecnecio , Radiofármacos , Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/epidemiología , Supervivencia sin Enfermedad , Prueba de Esfuerzo , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Medición de Riesgo , Factores de Tiempo , Tomografía Computarizada de Emisión de Fotón Único
9.
Phys Rev B Condens Matter ; 50(8): 5699-5702, 1994 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-9976917
10.
Opt Lett ; 17(24): 1764-6, 1992 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-19798309

RESUMEN

A novel method for measuring the beam quality of short, powerful laser pulses is presented. The method is based on the Z-scan technique used to investigate the nonlinear susceptibilities of optical materials. It is shown that both two-photon absorption and nonlinear refraction of a nonlinear sample can be used to obtain information about the spatial quality of the pulses.

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