The effect of sleeve gastrectomy on oxidative stress in obesity

High concentrations of free radicals are present in the blood of obese patients. Free radicals are associated with endothelial dysfunction, diabetes, and neoplastic transformation, all conditions that are closely related to obesity. The purpose of our study was to determine whether bariatric surgery modifies the production of free radicals in obese patients. In total, 20 patients with morbid obesity, who were candidates for laparoscopic sleeve gastrectomy (SG), and 18 controls were enrolled in the study. Oxidative stress was studied in obese subjects before and after sleeve gastrectomy. The evaluation of oxidative stress was carried out on blood samples using electron paramagnetic resonance, a refined spectroscopic technique used to identify and quantify the major free radicals, such as •OH, O2•, ONOO-, and NO. Oxidative stress was higher in subjects with morbid obesity prior to surgery, compared to the controls (CP• 9.9 ± 0.3 µM vs. 5.8 ± 0.2 µM). After SG, values decreased to levels comparable to those of controls (CP• 5.4 ± 0.2 µM). Further analysis identified O2• as the main free radical responsible for the oxidative stress. Obesity is associated with an increased blood concentration of free radicals. The normalization of free radicals after sleeve gastrectomy highlights another important benefit of this bariatric surgery technique

A possible role for selenoprotein glutathione peroxidase (GPx1) and thioredoxin reductases (TrxR1) in thyroid cancer. Our experience in thyroid surgery

Abstract Background: Oxidative stress is responsible for some alterations in the chemical structure and, consequently, in the function of proteins, lipids, and DNA. Recent studies have linked oxidative stress to cancers, particularly thyroid cancer, but the mechanisms remain unclear. Here, we further characterize the role of oxidative stress in thyroid cancer by analyzing the expression of two selenium antioxidant molecules, glutathione peroxidase (GPx1) and thioredoxin reductase (TrxR1) in thyroid cancer cells. Methods: Samples of both healthy thyroid tissue and thyroid tumor were taken for analysis after total thyroidectomy. The expression of GPx1 and TrxR1 was revealed by Western blot analysis and quantified by densitometric analyses, while the evaluation of free radicals was performed by Electron Paramagnetic Resonance (EPR)-spin trapping technique. Results: Our results show a decrease in the expression of GPx1 and TrxR1 (− 45.7 and − 43.2% respectively, p < 0.01) in the thyroid cancer cells compared to the healthy cells. In addition, the EPR technique shows an increase of free radicals in tumor tissue, significantly higher than that found in healthy thyroid tissue (+ 116.3%, p < 0.01). Conclusions: Our findings underscore the relationship between thyroid cancer and oxidative stress, showing the imbalance of the oxidant/antioxidant system in thyroid cancer tissue. These results suggest that either the inability to produce adequate antioxidant defense or an increased consumption of antioxidants, due to the hyper-production of free radicals, may play a crucial role in thyroid cancer. Keywords: Oxidative stress, Thyroid cancer, Glutathione peroxidase (GPx1), Thioredoxin reductases (TrxR1), Selenium enzyme

Spider surgical system versus multiport laparoscopic surgery. Performance comparison on a surgical simulator

BACKGROUND: The rising interest towards minimally invasive surgery has led to the introduction of laparo-endoscopic single site (LESS) surgery as the natural evolution of conventional multiport laparoscopy. However, this new surgical approach is hampered with peculiar technical difficulties. The SPIDER surgical system has been developed in the attempt to overcome some of these challenges. Our study aimed to compare standard laparoscopy and SPIDER technical performance on a surgical simulator, using standardized tasks from the Fundamentals of Laparoscopic Surgery (FLS). METHODS: Twenty participants were divided into two groups based on their surgical laparoscopic experience: 10 PGY1 residents were included in the inexperienced group and 10 laparoscopists in the experienced group. Participants performed the FLS pegboard transfers task and pattern cutting task on a laparoscopic box trainer. Objective task scores and subjective questionnaire rating scales were used to compare conventional laparoscopy and SPIDER surgical system. RESULTS: Both groups performed significantly better in the FLS scores on the standard laparoscopic simulator compared to the SPIDER. Inexperienced group: Task 1 scores (median 252.5 vs. 228.5; p = 0.007); Task 2 scores (median 270.5 vs. 219.0; p = 0.005). Experienced group: Task 1 scores (median 411.5 vs. 309.5; p = 0.005); Task 2 scores (median 418.0 vs. 331.5; p = 0.007). Same aspects were highlighted for the subjective evaluations, except for the inexperienced surgeons who found both devices equivalent in terms of ease of use only in the peg transfer task. CONCLUSIONS: Even though the SPIDER is an innovative and promising device, our study proved that it is more challenging than conventional laparoscopy in a population with different degrees of surgical experience. We presume that a possible way to overcome such challenges could be the development of tailored training programs through simulation methods. This may represent an effective way to deliver training, achieve mastery and skills and prepare surgeons for their future clinical experience

Perioperative care in elderly patients undergoing thyroid surgery

AbstractThe features of western world population are rapidly changing. The increment geriatric population obliges clinicians to implement specific recommendations and guidelines to manage these patients.In the field of thyroid surgery, when indications are represented by benign conditions, surgeons and endocrinologists tent to avoid surgery for the increased perioperative risks in the over 70 year old population.We reviewed our experience in thyroid surgery in geriatric patients within the environment of a “week surgery unit”. This unit was conceived to offer a highly specialized setting for thyroid patients needing short stay after surgery.Results showed that the surgical outcomes were comparable to the ones from third surgery in young patients.The week surgery approach is the best and safest formula to offer to the geriatric population needing thyroid surgery

P-Selectin as a new gender associated biomarker in patients with metabolic syndrome

[No abstract available

Thyroglobulin measurement in the washout of fine needle aspirates for the diagnosis of suspicious cervical lymph nodes

Ultrasound-guided fine-needle aspiration cytology (FNAC) for suspicious cervical lymph nodes (CLN) is the gold standard technique for the identification of metastases from differentiated thyroid carcinomas. Thyroglobulin protein (Tgp) assay in the washout of needles employed for FNA biopsies (FNAB) has been reported to refine and support FNAC performances, especially in cases of inadequate sampling or cystic lymph nodes. In the present work, we evaluated the usefulness of routine measurement of Tgp in the FNAB washout of suspicious cervical lymph nodes (CLN), and its ability to increase the FNAC accuracy in the diagnosis of metastatic CLN. A case study of 45 CLN with histological diagnosis from 36 patients was analyzed. Histology showed metastases from papillary thyroid carcinomas (PTC) in 31 CLN, from anaplastic thyroid cancer (ATC) in 3 CLN, from medullary thyroid cancer (MTC) in 4 CLN, and metastases from extrathyroidal malignancies in 5 CLN. Two CLN analyzed were found to be non-neoplastic. The overall accuracy of FNAC was 82.9%, and that of Tgp was 91.1%, not statistically different. However, Tgp determination was found essential in 4 cases of metastatic CLN from DTC with inadequate cytology, and in 1 case in which the FNAC provided a false negative result. We demonstrated that FNAC and Tgp assay show similar diagnostic accuracies, and that Tgp measurement may represent the only available information in case of inadequate lymph node sampling or cystic lymph nodes

Metabolomic Reprogramming Detected by 1H-NMR Spectroscopy in Human Thyroid Cancer Tissues

Thyroid cancer cells demonstrate an increase in oxidative stress and decreased antioxidant action, but the effects of this increased oxidative stress on cell function remain unknown. We aimed to identify changes in the metabolism of thyroid cancer cells caused by oxidative stress, using proton nuclear magnetic resonance (1H-NMR) spectroscopy. Samples of thyroid cancer and healthy thyroid tissue were collected from patients undergoing thyroidectomy and analyzed with 1H-NMR spectroscopy for a wide array of metabolites. We found a significant increase in lactate content in thyroid cancer tissue compared to healthy tissue. Metabolomic analysis demonstrated significant differences between cancer tissue and healthy tissue, including an increase in aromatic amino acids, and an average decrease in citrate in thyroid cancer tissue. We hypothesize that these changes in metabolism may be due to an oxidative stress-related decrease in activity of the Krebs cycle, and a shift towards glycolysis in cancer tissue. Thus, thyroid cancer cells are able to reprogram their metabolic activity to survive in conditions of high oxidative stress and with a compromised antioxidant system. Our findings, for the first time, suggested a connection between oxidative stress and the alteration of the metabolic profile in thyroid tumors

Il ruolo dello stress ossidativo nei tumori della tiroide, valutato attraverso la spettroscopia di risonanza paramagnetica elettronica e di risonanza magnetica nucleare: la nostra esperienza in chirurgia tiroidea

In molti casi , nelle cellule tumorali tiroidee è stato evidenziato un aumento dello stress ossidativo ed un deficit nel sistema antiossidante, ma gli effetti dello stress ossidativo sulla funzione cellulare rimangono ancora in gran parte sconosciuti. In questo studio abbiamo approfondito il ruolo di alcuni enzimi antiossidanti contenenti selenio, come glutatione perossidasi (GPx1) e tioredossina reduttasi (TrxR1), nei tumori della tiroide, valutando anche, mediante la spettroscopia di Risonanza Paramagnetica Elettronica (EPR), la formazione diretta dei radicali liberi nelle cellule tumorali. Inoltre, utilizzando la spettroscopia di risonanza magnetica nucleare ad alta risoluzione (HR-NMR), abbiamo identificato alcuni metaboliti nelle cellule tumorali della tiroide, che potrebbero essere l’espressione di un cambiamento del metabolismo cellulare in questo tipo di tumore. Campioni di carcinoma tiroideo e tessuto tiroideo sano sono stati raccolti da pazienti sottoposti a tiroidectomia totale per tumore tiroideo ed utilizzati per eseguire sia le analisi spettroscopiche con EPR e NMR, sia la valutazione dell’espressione degli enzimi antiossidanti. Nei nostri campioni abbiamo riscontrato un aumento significativo della formazione dei radicali liberi, mediante spettroscopia EPR, ed una riduzione sia dell’espressione degli enzimi antiossidanti GPx1 e TrxR1. L'analisi metabolomica, condotta mediante spettroscopia NMR, ha dimostrato, inoltre, una differenza significativa nell’espressione di alcuni metaboliti nel tessuto sano, rispetto al tessuto tumorale, evidenziando, in quest’ultimo, una riduzione di succinato, aspartato, mioinositolo, Cho, citrato e glutatione e un aumento di glutammato e acetato. Questi cambiamenti nel metabolismo cellulare riflettono una riduzione dell'attività del ciclo di Krebs a favore della glicolisi nei tumori tiroidei, in presenza di un significativo aumento dello stress ossidativo. I nostri risultati evidenziano che le cellule tumorali tiroidee sono in grado di riprogrammare la loro attività metabolica per sopravvivere in condizioni di elevato stress ossidativo e con un sistema antiossidante compromesso, evidenziando per la prima volta, una connessione tra stress ossidativo e l'alterazione del profilo metabolico nei tumori della tiroide