5-year Follow-up of Reimplanted Parathyroid Glands in Forearm Subcutaneous Tissue During Thyroidectomy. A Confirmation of Graft Vitality in a Large Series of Patients.

INTRODUCTION: The aim of this study is to assess the outcomes of parathyroid gland reimplantation with PR-FaST technique in patients undergoing thyroid surgery, focusing on graft functionality over a 5-year follow-up period. MATERIALS AND METHODS: We analyzed data from 131 patients who underwent parathyroid reimplantation using the PR-FaST technique during thyroid surgery due to inadvertent parathyroid removal or evident vascular damage. Postoperative evaluations included serum calcium (Ca), magnesium (Mg), and phosphorus (P) analyses on the 1st and 2nd postoperative days, at 10 days, and at 1, 3, 6 months, 1 year, and 5 years of follow-up. Additionally, the mean values of serum intact parathyroid hormone (iPTH) concentration were measured from blood samples collected from both the reimplanted arm (iPTH RA) and non-reimplanted arm (iPTH NRA) within the same period. RESULTS: Among 131 patients, at 10 days post-surgery, only 46 patients (35.1%) out of 131 exhibited graft viability (iPTH ratio >1.5). This percentage increased to 72.8% (94 patients) after 1 month and further to 87.8% (108 patients) after 3 months post-surgery. At 1 year, 84.7% of patients showed good graft functionality. After 5 years, the percentage remained stable, with graft viability observed in 81.3% of patients. Only 91 of the initial 131 patients completed follow-up up to 5 years, with a dropout rate of 30.5 %. CONCLUSIONS: Parathyroid reimplantation using the PR-FaST technique is a viable option for patients undergoing thyroidectomy and has been shown to be a reproducible and effective technique in most patients, with sustained graft functionality and parathyroid hormone production over a 5-year follow-up period.

Impact of Intermittent Intraoperative Neuromonitoring (IONM) on the Learning Curve for Total Thyroidectomy by Residents in General Surgery.

INTRODUCTION: Recurrent laryngeal nerve (RNL) identification constitutes the standard in thyroidectomy. Intraoperative nerve monitoring (IONM) has been introduced as a complementary tool for RLN functionality evaluation. The aim of this study is to establish how routine use of IONM can affect the learning curve (LC) in thyroidectomy. METHODS: Patients undergoing total thyroidectomy performed by surgery residents in their learning curve course in 2 academic hospitals, were divided into 2 groups: Group A, including 150 thyroidectomies performed without IONM by 3 different residents, and Group B, including 150 procedures with routine use of intermittent IONM, by other 3 different residents. LC was measured by comparing operative time (OT), its stabilization during the development of the LC, perioperative complication rate. RESULTS: As previously demonstrated, the LC was achieved after 30 procedures, in both groups, with no differences due to the use of IONM. Similarly, there were no significant differences among the 2 groups, and between subgroups independently matched, for both OT and complications, even when comparing RLN palsy. Direct nerve visualization and IONM assessment rates were comparable in all groups, and no bilateral RLN palsy (transient or permanent) were reported. No case of interrupted procedure to unilateral lobectomy, due to evidence of RLN injury, was reported. CONCLUSIONS: The study demonstrates that the use of IONM thyroid surgery, despite requiring a specific training with experienced surgeons, does not particularly affect the learning curve of residents approaching this kind of surgery, and for this reason its routine use should be encouraged even for trainees.

Readmission and reoperation rates after laparoscopic bariatric surgery in an Italian center of excellence.

BACKGROUND: The aim of this study was to analyze short-term outcomes focusing on readmissions after laparoscopic bariatric metabolic surgery (BMS) in an Italian academic Bariatric Center of Excellence IFSO-European Chapter (EC). METHODS: This is a retrospective study based on the analysis of a prospectively maintained institutional database. Patients aged between 18 and 65 years who underwent primary BMS and/or revisional BMS (RBMS) between 2012 and 2021 were included. Primary endpoint was to analyze the readmission rate at 30 postoperative days. The secondary endpoint involved assessing the causes of readmission within 30 days of discharge, the rates, and types of reoperations and/or additional procedures related to the first surgery, and the outcomes of readmitted patients. RESULTS: A total of 2297 patients were included in the study. Among them, 2143 underwent primary surgery and 154 patients underwent RBMS. Eighty-two percent of the Enhanced Recovery after Surgery (ERAS) protocol items were applied starting from 2016. Within 30 days after discharge, 48 patients (2.09%) were readmitted. Overall readmission rate following primary and revisional BMS was 2.15%, respectively 1.30%. Ten readmitted patients (20.8%) had complications graded IIIb or more (Clavien-Dindo classification) and needed additional procedures. Mortality rate was 4.17% among readmitted patients. CONCLUSIONS: Only 2.09% of patients undergoing laparoscopic bariatric surgery were readmitted. Of these, 20.8% required additional procedures. Standardization of surgical techniques and perioperative protocols in a bariatric center of excellence resulted in a low readmission rate even in RBMS.

Application of enhanced recovery after surgery (ERAS) protocols in adrenal surgery: A retrospective, preliminary analysis.

BACKGROUND: The present study was conducted to evaluate the impact of enhanced recovery after surgery (ERAS) pathway in patients undergoing laparoscopic adrenalectomy (LA) for primary and secondary adrenal disease, in reducing the length of primary hospital stay and return to daily activities. MATERIALS AND METHODS: This retrospective study was carried out on 61 patients who underwent LA. A total of 32 patients formed the ERAS group. A total of 29 patients received conventional perioperative care and were assigned as the control group. Groups were compared in terms of patient's characteristics (sex, age, pre-operative diagnosis, side of tumour, tumour size and co-morbidities), post-operative compliance (anaesthesia time, operative time, post-operative stay, post-operative numeric rating scale (NRS) score, analgesic assumption and days to return to daily activities) and post-operative complications. RESULTS: No significant differences in anaesthesia time ( P = 0.4) and operative time ( P = 0.6) were reported. NRS score 24 h postoperatively was significantly lower in the ERAS group ( P < 0.05). The analgesic assumption in post-operative period in the ERAS group was lower ( P < 0.05). ERAS protocol led to a significantly shorter length of post-operative stay ( P < 0.05) and to return to daily activities ( P < 0.05). No differences in peri-operative complications were reported. DISCUSSION: ERAS protocols seem safe and feasible, potentially improving perioperative outcomes of patients undergoing LA, mainly improving pain control, hospital stay and return to daily activities. Further studies are needed to investigate overall compliance with ERAS protocols and their impact on clinical outcomes.

Passive Recording of Bioelectrical Signals from Non-Excitable Cells by Fluorescent Mirroring.

Bioelectrical variations trigger different cell responses, including migration, mitosis, and mutation. At the tissue level, these actions result in phenomena such as wound healing, proliferation, and pathogenesis. Monitoring these mechanisms dynamically is highly desirable in diagnostics and drug testing. However, existing technologies are invasive: either they require physical access to the intracellular compartments, or they imply direct contact with the cellular medium. Here, we present a novel approach for the passive recording of electrical signals from non-excitable cells adhering to 3D microelectrodes, based on optical mirroring. Preliminary results yielded a fluorescence intensity output increase of the 5,8% in the presence of a HEK-293 cell on the electrode compared to bare microelectrodes. At present, this technology may be employed to evaluate cell-substrate adhesion and monitor cell proliferation. Further refinements could allow extrapolating quantitative data on surface charges and resting potential to investigate the electrical phenomena involved in cell migration and cancer progression.

Clinical and Radiological Evaluation of a Self-Condensing Bone Implant in One-Stage Sinus Augmentation: A 3-Year Follow-Up Retrospective Study.

Stabilization of dental implants in the sinus region with a bone height below 4 mm gen-erally requires a two-stage sinus floor elevation surgery. To improve this aspect, the aim of this retrospective study was to demonstrate the feasibility of performing a one-stage maxillary sinus augmentation using an innovative self-condensing implant design, even in case of a bone height close to 2 mm. Clinical and radiological outcomes from 54 patients (26 females; 28 males; 69 total implants positioned) were analyzed 3 years post-surgery. The three-dimensional grafts change was evaluated by Cone-Beam Computed Tomography (CBCT) before surgery (T0), immediately after surgery (T1), and 1-year post-surgery (T2). The sinus floor levels measured at the medial (M-W), middle (MD-W), and lateral (L-W) walls reported: M-W of 1.9 ± 2.4 mm (T1) and 1.7 ± 2.6 mm (T2); MD-W of -0.1 ± 2.7 mm (T1) and 0.7 ± 2.4 mm (T2); L-W of 3.1 ± 3.0 mm (T1) and 3.1 ± 3.0 mm (T2); besides a bone crest height (C-F) of 4.6 ± 2.0 mm (T1) and 12.1 ± 1.4 mm (T2). Moreover, after 3 years only 1 implant was lost, and so an implant survival rate of 98.55% was recorded. In conclusion, these results suggest the efficacy of using this implant design for a one-stage sinus lift approach, not only in terms of increased implant survival rate and decreased marginal bone loss, but also for its potential applicability in case of reduced bone height.

Ultrasound-guided Transversus Abdominis Plane Block is Effective as Laparoscopic Trocar site infiltration in Postoperative Pain Management in Patients Undergoing Adrenal Surgery.

BACKGROUND: Pain management in patients undergoing laparoscopy is still a matter of debate as several techniques have been proposed to reduce postoperative analgesic consumption and improve recovery. Among these, transversus abdominis plane (TAP) block is considered as safe, effective, and easy to perform under ultrasound guidance; even so, recently laparoscopically guided trocar site anesthetic infiltration has been proposed as a "surgeon-dependent alternative to TAP block." The aim of this evaluation is to compare these analgesic techniques in the setting of laparoscopic adrenalectomy. METHODS: This is a retrospective evaluation of a prospectively maintained database. Patients were divided into two groups: Group A patients received laparoscopic-assisted trocar site infiltration of ropivacaine; Group B patients received bilateral ultrasound-guided TAP block with ropivacaine. All patients received 24 h infusion of 20 mg morphine postoperatively; pain was checked at 6, 24 and 48 h after surgery. A rescue analgesia was given if numerical rating scale (NRS) score was > 4 or on patient request. RESULTS: One hundred and three patients were enrolled in the evaluation (57 in group A and 46 in group B). There were no differences in operative time, complications and postoperative stay, and no complications related to trocar site infiltration. There were no differences in NRS at 6, 24, and 48 hours as well as in patients requiring further analgesic administration. CONCLUSIONS: Laparoscopic-guided trocar site ropivacaine infiltration has similar pain outcomes compared to ultrasound-guided TAP block in the management of postoperative pain in patients undergoing laparoscopic adrenalectomy. Since there is no difference among these techniques, the decision can be based on surgeon or anesthesiologist preference.

Multicenter retrospective cohort Italian study on elective laparoscopic cholecystectomy performed by the surgical residents.

PURPOSE: This retrospective multicenter cohort study aimed to evaluate the clinical outcomes (mortality rate, operative time, complications) of elective laparoscopic cholecystectomy (LC) when performed by a surgical resident in comparison to experienced consultant in the backdrop of Italian academic centers. METHODS: Retrospective review of all patients undergoing elective LC between January 2016 and January 2022 at six teaching hospitals across Italy was performed. Cases were identified using the Current Procedural Terminology (CPT) code 5123 (LC without cholangiogram). All cases of emergency surgery, ASA score > 3, or when cholecystectomy was performed with another surgical procedure, were excluded. All suitable cases were divided into 2 groups based on primary surgeon: consultant or senior resident. Main outcome was complication rates (intraoperative and peri/postoperative); secondary outcomes included operative time, the length of stay, and the rate of conversion to open. RESULTS: A total of 2331 cases (1425 females) were included, of which, consultants performed 1683 LCs (72%), while the residents performed 648 (28%) surgeries. The groups were statistically comparable regarding demographics, history of previous abdominal surgery, operative time, or intraoperative complications. The rate of conversion to open cholecystectomy was 1.42% for consultant and none for resident (p = 0.02). A statistically significant difference was observed between groups regarding the average length of stay (2.2 ± 3 vs 1.6 ± 1.3 days p = 0.03). Similarly, postoperative complications (1.7% vs 0.5%) resulted in statistically significant (p = 0.02) favoring resident group. CONCLUSIONS: Our study demonstrates that in selected patients, senior residents can safely perform LC when supervised by senior staff surgeons.

Long-term outcomes of sleeve gastrectomy as a revisional procedure after failed gastric band: a multicenter cross-matched cohort study.

Laparoscopic adjustable gastric band (LAGB) is the bariatric procedure most likely subject to revisional surgery. Both laparoscopic sleeve gastrectomy (LSG) and Roux-en-Y gastric bypass (LRYGB) represent viable options, but the long-term results are still lacking. In 2014, we published the 2-year follow-up of our multicenter cohort of revisional LSG after failed LAGB. Evaluate the long-term follow-up (median 9.3 years) of the same cohort of patients. University and primary-care hospitals, Italy. We retrospectively examined a prospectively maintained database of the previously published multicenter cohort of 56 patients who underwent LSG after failed LAGB between 2008-2011. The control group included cross-matched non-revisional LSGs. The primary endpoint was weight loss, secondary endpoints co-morbidities, and the need for further bariatric surgery. The study group included 44 patients and the control group 56. We found %EWL 53% Vs. 67% (p = .021), %EBMIL (54 Vs. 68%, p = .018), %TWL (26 Vs. 34%, p = .002). We also found more severe GERD (gastroesophageal reflux disease) symptoms in the revisional than in the primary group (9.0 vs. 1.8% mild and 23.0 vs. 3.0% severe). Ten patients from the revisional group (22.7%) vs. eight in the primary group (13%) underwent further bariatric surgery (LRYGB). Our results showed less favorable weight loss in revisional than primary LSG after LABG, higher prevalence of GERD, and a more frequent need for further revisional surgery. Despite the study's limitations, the present data suggest that the long-term outcomes may offset the possible reduced short-term complication rate after revisional sleeve gastrectomy for a failed LABG.

Colorectal cancer after bariatric surgery (Cric-Abs 2020): Sicob (Italian society of obesity surgery) endorsed national survey.

BACKGROUND: The published colorectal cancer (CRC) outcomes after bariatric surgery (BS) are conflicting, with some anecdotal studies reporting increased risks. The present nationwide survey CRIC-ABS 2020 (Colo-Rectal Cancer Incidence-After Bariatric Surgery-2020), endorsed by the Italian Society of Obesity Surgery (SICOB), aims to report its incidence in Italy after BS, comparing the two commonest laparoscopic procedures-Sleeve Gastrectomy (SG) and Roux-en-Y gastric bypass (GBP). METHODS: Two online questionnaires-first having 11 questions on SG/GBP frequency with a follow-up of 5-10 years, and the second containing 15 questions on CRC incidence and management, were administered to 53 referral bariatric, high volume centers. A standardized incidence ratio (SIR-a ratio of the observed number of cases to the expected number) with 95% confidence intervals (CI) was calculated along with CRC incidence risk computation for baseline characteristics. RESULTS: Data for 20,571 patients from 34 (63%) centers between 2010 and 2015 were collected, of which 14,431 had SG (70%) and 6140 GBP (30%). 22 patients (0.10%, mean age = 53 ± 12 years, 13 males), SG: 12 and GBP: 10, developed CRC after 4.3 ± 2.3 years. Overall incidence was higher among males for both groups (SG: 0.15% vs 0.05%; GBP: 0.35% vs 0.09%) and the GBP cohort having slightly older patients. The right colon was most affected (n = 13) and SIR categorized/sex had fewer values < 1, except for GBP males (SIR = 1.07). CONCLUSION: Low CRC incidence after BS at 10 years (0.10%), and no difference between procedures was seen, suggesting that BS does not trigger the neoplasm development.

Binding of tyrosine kinase inhibitor to epidermal growth factor receptor: surface-enhanced infrared absorption microscopy reveals subtle protein secondary structure variations.

Surface-Enhanced Infrared Absorption (SEIRA) has been proposed as a valuable tool for protein binding studies, but its performances have been often proven on model proteins undergoing severe secondary structure rearrangements, while ligand binding only marginally involves the protein backbone in the vast majority of the biologically relevant cases. In this study we demonstrate the potential of SEIRA microscopy for highlighting the very subtle secondary structure modifications associated with the binding of Lapatinib, a tyrosine kinase inhibitor (TKI), to epidermal growth factor receptor (EGFR), a well-known driver of tumorigenesis in pathological settings such as lung, breast and brain cancers. By boosting the performances of Mid-IR plasmonic devices based on nanoantennas cross-geometry, accustoming the protein purification protocols, carefully tuning the protein anchoring methodology and optimizing the data analysis, we were able to detect EGFR secondary structure modification associated with few amino acids. A nano-patterned platform with this kind of sensitivity bridges biophysical and structural characterization methods, thus opening new possibilities in studying of proteins of biomedical interest, particularly for drug-screening purposes.

Telematics pre-operative psychological and nutritional assessment in candidates for bariatric surgery during COVID-19 phase 2: a pilot prospective observational study.

BACKGROUND: Obesity represents a risk factor for COVID-19 infection. Therefore, in order to reduce COVID-19 related comorbidities in obese population a continuation of obesity treatment is needed. However, bariatric procedures were postponed because of COVID-19 restrictions, delaying treatment for obese patients seeking for surgery. This study aimed to test the feasibility of a telematics pre-operative psychological and nutritional assessment as an alternative tool during COVID-19 outbreak. METHODS: Twenty-six patients were contacted. The pre-operative assessment consisted in 3-weekly one-to-one online sessions and a final in-person multidisciplinary session. The protocol feasibility has been evaluated on the following outcome: rejection rate (%), dropout rate (%), compliance and satisfaction's degree. RESULTS: Eighteen participants completed the whole protocol and 10% dropped-out. Seventy-two percent of participants obtained an excess weight loss ≥5%. All participants were satisfied of the telematics assessment. CONCLUSIONS: COVID-19 emergency has changed standard hospital procedures and this study could represent a landmark for an online pre-operative assessment method to adopt in case of new restrictions.

Hiatal Surface Area's CT scan measurement is useful in hiatal hernia's treatment of bariatric patients.

INTRODUCTION: Hiatal surface area (HSA) measurement has been recently proposed as useful tool for tailored treatment of hiatal defects. Multidetector CT scan (MDCT) of the hiatal area was shown to be useful in hiatal hernia (HH) management. PURPOSE: MDCT preoperative HSA measurements validation as a useful method in the surgical repair decision making process of hiatal defects in candidates to antireflux ± bariatric surgery. MATERIAL AND METHODS: Twenty-five obese patients (group A), candidates to laparoscopic cruroplasty ± bariatric surgery, were prospectively evaluated preoperatively and after one year, using an original MDCT algorithm, compared with intraoperative HSA measurement. Twelve non-obese (group B) and 12 obese patients (group C), without GERD or HH, were used as control groups. RESULTS: Median preoperative HSA was 7.9 cm2, (interquartile IQR 5.97-9.80) while intraoperative median HSA was 6 cm2 (6-9.5), p = .84. Postoperative median HSA was 3.8 cm2 (3.21-4.8), showing the efficacy of cruroplasty, comparable with HSA calculated in the control groups (3.98 for B and 3.69 cm2 for C, p = .8547). No statistically significant difference between MDCT preoperative measurement and intraoperative findings was observed. CONCLUSIONS: Preliminary results demonstrate MDCT scan HSA measurements as a valid, non-invasive method to predict intraoperative findings. It allows the HSA monitoring in order to correlate the symptoms onset and failure of cruroplasty.

Concomitant hiatal hernia repair during bariatric surgery: does the reinforcement make the difference?

BACKGROUND: Hiatal hernia repair (HHR) is still controversial during bariatric procedures, especially in case of laparoscopic sleeve gastrectomy (LSG). AIMS: to report the long-term results of concomitant HHR, evaluating the safety and efficacy of posterior cruroplasty (PC), simple or reinforced with biosynthetic, absorbable Bio-A® mesh (Gore, Flagstaff, AZ, USA). Primary endpoint: PC's failure, defined as symptomatic HH recurrence, nonresponding to medical treatment and requiring revisional surgery. METHODS: The prospective database of 1876 bariatric operations performed in a center of excellence between 2011-2019 was searched for concomitant HHR. Intraoperative measurement of the hiatal surface area (HSA) was performed routinely. RESULTS: A total of 250 patients undergone bariatric surgery and concomitant HHR (13%). Simple PC (group A, 151 patients) was performed during 130 LSG, 5 re-sleeves and 16 gastric bypasses; mean BMI 43.4±5.8 kg/m2, HSA mean size 3.4±2 cm2. Reinforced PC (group B) was performed in 99 cases: 62 primary LSG, 22 LGB and 15 revisions of LSG; mean BMI 44.6±7.7 kg/m2, HSA mean size 6.7±2 cm2. PC's failure, with intrathoracic migration (ITM) of the LSG was encountered in 12 cases (8%) of simple vs. only 4 cases (4%) of reinforced PC (P=0.23); hence, a repeat, reinforced PC and R-en-Y gastric bypass (LRYGB) was performed laparoscopically in all cases. No mesh-related complications were registered perioperatively or after long-term follow-up (mean 50 months). One case of cardiac metaplasia without goblet cells was detected 4 years postoperatively; conversion to LRYGB, with reinforced redo of the PC was performed. The Cox hazard analysis showed that the use of more than four stitches for cruroplasty represents a negative factor on recurrence (HR=8; P<0.05). CONCLUSIONS: An aggressive search for and repair of HH during any bariatric procedure seems advisable, allowing a low HH recurrence rates. Additional measures, like mesh reinforcement of crural closure with biosynthetic, absorbable mesh, seem to improve results on long term follow-up, especially in case of larger hiatal defects. In our experience, reinforcement of even smaller defects seems advisable in obese population.

Multiplexed Discrimination of Single Amino Acid Residues in Polypeptides in a Single SERS Hot Spot.

The SERS-based detection of protein sequences with single-residue sensitivity suffers from signal dominance of aromatic amino acid residues and backbones, impeding detection of non-aromatic amino acid residues. Herein, we trap a gold nanoparticle in a plasmonic nanohole to generate a single SERS hot spot for single-molecule detection of 2 similar polypeptides (vasopressin and oxytocin) and 10 distinct amino acids that constitute the 2 polypeptides. Significantly, both aromatic and non-aromatic amino acids are detected and discriminated at the single-molecule level either at individual amino acid molecules or within the polypeptide chains. Correlated with molecular dynamics simulations, our results suggest that the signal dominance due to large spatial occupancy of aromatic rings of the polypeptide sidechains on gold surfaces can be overcome by the high localization of the single hot spot. The superior spectral and spatial discriminative power of our approach can be applied to single-protein analysis, fingerprinting, and sequencing.

Long-Term Results After Laparoscopic Sleeve Gastrectomy with Concomitant Posterior Cruroplasty: 5-Year Follow-up.

BACKGROUND: Hiatal hernia (HH) repair during laparoscopic sleeve gastrectomy (LSG) has been advocated to reduce the incidence of postoperative gastroesophageal reflux disease (GERD) and/or intrathoracic migration (ITM). The necessity of intraoperative repair in asymptomatic patients is still controversial. Previous, mid-term results of a prospective, comparative study evaluating posterior cruroplasty concomitant with LSG (group A 48 patients with simple vs. group B 48 reinforced with bioabsorbable mesh) confirmed the safety and effectiveness of simultaneous procedures. Present aim was to report the 60 months follow-up update, evaluating GERD and esophageal lesions' incidence and HH's recurrence. RESULTS: Follow-up was completed in 87.5% of the patients. Recurrent GERD was registered in 6/38 (15.7%, group A) and in 9/46 (19.5%, group B) (p = 1.0000). Grade A esophagitis and GERD was shown in 2 patients (5.2%), respectively 2 (4.3%) of each group (p = 1.0000), and recurrent HH was confirmed subsequently by contrast study and CT scan. Neither Barrett's lesions nor de novo GERD was found in any patient. Failure of the cruroplasty with ITM was recorded in 7 patients from group A (18.4%) and 2 patients from group B (4.3%) p < 0.05; hence, a repeat posterior, reinforced cruroplasty was performed in all cases. A total of 12 patients (14.2%, 8 respective 4) were converted within 5 years for persistent/recurrent GERD, with only 1 case of de novo (group B). CONCLUSIONS: Accurate patient selection and proper sleeve technique, combined with posterior cruroplasty (simple or reinforced) ensure effectiveness, with a rate of failure (HH recurrence) at 5 years of 10.7%.

Time resolved and label free monitoring of extracellular metabolites by surface enhanced Raman spectroscopy.

Metabolomics is an emerging field of cell biology that aims at the comprehensive identification of metabolite levels in biological fluids or cells in a specific functional state. Currently, the major tools for determining metabolite concentrations are mass spectrometry coupled with chromatographic techniques and nuclear magnetic resonance, which are expensive, time consuming and destructive for the samples. Here, we report a time resolved approach to monitor metabolite dynamics in cell cultures, based on Surface Enhanced Raman Scattering (SERS). This method is label-free, easy to use and provides the opportunity to simultaneously study a broad range of molecules, without the need to process the biological samples. As proof of concept, NIH/3T3 cells were cultured in vitro, and the extracellular medium was collected at different time points to be analyzed with our engineered SERS substrates. By identifying individual peaks of the Raman spectra, we showed the simultaneous detection of several components of the conditioned medium, such as L-tyrosine, L-tryptophan, glycine, L-phenylalanine, L-histidine and fetal bovine serum proteins, as well as their intensity changes during time. Furthermore, analyzing the whole Raman data set with the Principal Component Analysis (PCA), we demonstrated that the Raman spectra collected at different days of culture and clustered by similarity, described a well-defined trajectory in the principal component plot. This approach was then utilized to determine indirectly the functional state of the macrophage cell line Raw 264.7, stimulated with the lipopolysaccharide (LPS) for 24 hours. The collected spectra at different time points, clustered by the PCA analysis, followed a well-defined trajectory, corresponding to the functional change of cells toward the activated pro-inflammatory state induced by the LPS. This study suggests that our engineered SERS surfaces can be used as a versatile tool both for the characterization of cell culture conditions and the functional state of cells over time.

Perioperative hemorrhagic complications after laparoscopic sleeve gastrectomy: four-year experience of a bariatric center of excellence.

BACKGROUND: Bleeding and gastric fistula are the most common postoperative complications after laparoscopic sleeve gastrectomy (LSG). The long stapler line represents the most frequent source of bleeding, which ranges between 0 and 20%. The aim of this retrospective study was to analyze the 4-year experience of a high-volume center with respect to the prevention and management of perioperative LSG bleeding. METHODS: The prospectively maintained database from June 2012 to June 2016 was reviewed. Outcomes, especially perioperative bleeding (until patient discharge), its management, and follow-ups, were analyzed. RESULTS: Out of 870 LSG (603 females, 267 males), 31 cases (3.5%) of postoperative complications were registered: bleeding was the most frequent complication (1.9%). Hemoperitoneum was managed laparoscopically in 9/17 patients (52.9%) with only one conversion to laparotomy (11.1%). Conservative treatment successfully controlled bleeding in 8/17 patients (47.1%). However, four patients (50%) developed an infected hematoma; two of them were treated conservatively with a CT-guided drainage, and the other two were complicated by late gastric leak treated laparoscopically. No mortalities occurred in the investigated cases. CONCLUSIONS: In a high-volume center, the expected incidence of bleeding after LSG is 1.7% even after the adoption of all preventive strategies. The intraoperative protocol for detecting silent bleeding was effective, and no cases of bleeding were observed since its application. Our findings showed that the conservative management of postoperative bleeding should be considered as a high-risk condition for late leakage.

A Model Study to Unravel the Complexity of Bio-Oil from Organic Wastes.

Binary and ternary mixtures of cellulose, bovine serum albumin (BSA) and tripalmitin, as biomass reference compounds for carbohydrates, proteins and triglycerides, respectively, were treated under hydrothermal liquefaction (HTL) conditions to describe the main reaction pathways involved in the process of bio-oil production from municipal organic wastes. Several analytical techniques (elemental analysis, GC-MS, atmospheric-pressure photo-ionisation high-resolution Fourier transform ion cyclotron resonance mass spectrometry, and 13 C cross-polarisation magic-angle spinning NMR spectroscopy) were used for the molecular-level characterisation of the resulting aqueous phase, solid residue and bio-oil, in particular. The main reaction pathways led to free fatty acids, fatty acid amides, 2,5-diketopiperazines and Maillard-type compounds as the main components of the bio-oil. The relationship of such compounds to the original components of the biomass was thus determined, which highlights the fate of the heteroatom-containing molecules in particular. Finally, the molecular composition of the bio-oils from our reference compounds was matched with that of the bio-oil from municipal organic waste biomass by comparing their high-resolution Fourier transform ion cyclotron resonance mass spectra, and we obtained a surprisingly high similarity. Hence, the ternary mixture acts as a reliable biomass model and is a powerful tool to clarify the degradation mechanisms that occur in the biomass under HTL treatment, with the ultimate goal to improve the HTL process itself by modulating the input of the organic starting matter and then the upgrading steps to bio-fuels.