Design and Experimental Validation of a 3D-Printed Embedded-Sensing Continuum Robot for Neurosurgery.

A minimally-invasive manipulator characterized by hyper-redundant kinematics and embedded sensing modules is presented in this work. The bending angles (tilt and pan) of the robot tip are controlled through tendon-driven actuation; the transmission of the actuation forces to the tip is based on a Bowden-cable solution integrating some channels for optical fibers. The viability of the real-time measurement of the feedback control variables, through optoelectronic acquisition, is evaluated for automated bending of the flexible endoscope and trajectory tracking of the tip angles. Indeed, unlike conventional catheters and cannulae adopted in neurosurgery, the proposed robot can extend the actuation and control of snake-like kinematic chains with embedded sensing solutions, enabling real-time measurement, robust and accurate control of curvature, and tip bending of continuum robots for the manipulation of cannulae and microsurgical instruments in neurosurgical procedures. A prototype of the manipulator with a length of 43 mm and a diameter of 5.5 mm has been realized via 3D printing. Moreover, a multiple regression model has been estimated through a novel experimental setup to predict the tip angles from measured outputs of the optoelectronic modules. The sensing and control performance has also been evaluated during tasks involving tip rotations.

Role of glucocorticoid receptor polymorphism in adrenal incidentalomas.

BACKGROUND: Adrenal incidentalomas (AI) have been associated with and an increased prevalence of metabolic and bone complications. The N363S and BclI polymorphisms of the glucocorticoid receptor (GR) have been associated with an increased sensitivity to glucocorticoid (GC). This observational study aims to evaluate whether BclI and N363S polymorphisms play a role in the development of complications in AI. MATERIALS AND METHODS: We enrolled 100 patients with AI (66 F; 34M). The presence of diabetes, arterial hypertension (AH), dyslipidaemia, osteoporosis and vertebral fracture (Fx), waist circumference and the Body Mass Index (BMI) were assessed. DNA samples were genotyped. Patients with wild-type BclI, wild-type N363S and heterozygous BclI polymorphism were classified as carriers of haplotype 1 (H1; n = 86), patients with homozygous BclI and heterozygous N363S polymorphism of GR of haplotype 2 (H2; n = 14). RESULTS: We found no clinical or biochemical differences between haplotype 1 and 2 groups, but a higher prevalence of the simultaneous presence of Fx plus AH in H2 patients (H2 n = 7, H1 n = 16, P = 0.01). Logistic regression analysis showed that the presence of Fx and of AH and the combination of the presence of Fx plus AH were associated with the H2 genotype regardless of the degree of cortisol secretion, age, BMI and BMD (OR 4.88, 95%CI 1.47-18.40, P = 0.05; OR 8.25, 95%CI 0.98-69.52, P = 0.05; OR 7.25, 95%CI 1.57-35.78, P = 0.011; respectively). CONCLUSIONS: In AI patients, the presence of the haplotype 2 of BclI and N363S is associated with the presence of AH, Fx and with the combination of Fx and AH.

Comparison between six-year therapy with long-acting somatostatin analogs and successful surgery in acromegaly: effects on cardiovascular risk factors.

CONTEXT: The effects of chronic therapy with long-acting somatostatin analogs (SSTa) on metabolic and cardiovascular parameters have been partially elucidated in acromegalic patients. OBJECTIVE: The objective of this study was to compare the long-term effects of SSTa treatment and successful surgery on GH/IGF-I secretion and cardiovascular risk parameters in acromegaly. DESIGN, PATIENTS, AND INTERVENTION: This was a retrospective study of 36 acromegalic patients treated with SSTa and evaluated after a median of 66 months and of 33 sex-, age-, and body mass index-matched cured patients evaluated after a similar period of remission, all from the Institute of Endocrine Sciences (Milan, Italy). MAIN OUTCOME MEASURES: The main outcome measures were fasting and post-oral load glucose homeostasis, hemoglobin A(1c), insulin sensitivity and secretion by several indexes, lipid profile, and blood pressure. RESULTS: Fasting and areas under the glucose response curve rose in patients controlled (n = 29) and not controlled (n = 7) by SSTa, becoming higher than those in cured subjects. A 1% hemoglobin A(1c) increase was observed in all nondiabetic SSTa patients, but not in cured subjects. Basal insulin secretion and resistance, evaluated by homeostasis model assessment, decreased in all SSTa patients, whereas oral glucose tolerance test-derived insulin secretion and resistance, evaluated by insulinogenic index and oral glucose tolerance test-derived insulin secretion, improved only in SSTa-treated controlled patients. Triglycerides did not change during SSTa, whereas high-density lipoprotein cholesterol increased in SSTa-treated controlled patients. At the last visit, the contemporary presence of at least three cardiovascular risk factors was more frequent in patients treated with SSTa than in cured subjects. CONCLUSIONS: SSTa therapy induces long-lasting disease control and improvement of insulin sensitivity and high-density lipoprotein cholesterol levels in responsive patients. The progressive glucose homeostasis alterations, observed independently from the degree of cure, suggest the need for glucose homeostasis and peripheral vascular complications monitoring during chronic SSTa treatment.