A Novel Indocyanine Green Fluorescence-Guided Laparoscopic Technique to Map the Site of Obscure Gastrointestinal Haemorrhage.

The aim of our study was to explore the feasibility of a novel fluorescence-guided laparoscopic technique to localize the obscure GI haemorrhage, using the vascular wash-out properties of indocyanine green (ICG). Method: The feasability study included patients with previous surgical modifications of the gut architecture, qualified as an overt obscure GI bleeding with an urgent need to be localized and controlled. Five mL of ICG was injected intravenously and laparoscopic infrared inspection was performed 30 minutes after the dye was eliminated from the bloodstream. The bleeding area mapping was demonstrated and the haemostasis was carefully performed using endoscopy or laparoscopic techniques. Results: A series of two cases were included in our fesability study so far. Case 1. A 43-year old male, who recently received a Laparoscopic Roux-en-Y gastric bypass (RYGB), developed a recurrent GI bleeding. Post dye wash-out intense signal was demonstrated at the level of duodenum and weaker at the gastric remnant. The laparoscopic trans-gastric exploration of the remnant identified an active bleeding source siding the stapled line and haemostasis was achieved with laparoscopic ligation using stitches. Case 2. A 66-year old male patient who underwent an open Whipple resection nine months before, was admitted for a repeated GI bleeding. The inspection of the biliopancreatic limb noticed an intense fluorescent signal toward the enteral proximal end. Upper digestive endoscopy confirmed the presence of an active bleeding source from ectopic jejunal varices siding the choledoco-jejunal anastomosis. Argon plasma coagulation was performed endoscopically and achieved hemostasis. Conclusions: A successful novel ICG fluorescence-guided laparoscopic mapping technique was used to localize the site of the obscure GI haemorrhage and to facilitate the prompt bleeding control. To the best of our knowledge these are the first published cases for which this technique was used.

The impact of the surgical technique on stenosis after laparoscopic sleeve gastrectomy.

BACKGROUND: Laparoscopic sleeve gastrectomy (LSG) has gained worldwide popularity in the last 10 years as self alone bariatric procedure. Symptomatic stenosis (SS) is a potential severe postoperative complication and it can be divided in organic stenosis (OS) and functional stenosis (FS). The aim of this paper is to propose a modified surgical technique to prevent FS. METHODS: A retrospective review on 5235 LSG performed in Ponderas Academic Hospital between January 2011 and December 2019, searched FS in two consecutive patients groups, divided based on the modified surgical technique introduced in 2015, with fixation of the gastric tube to the prepancreatic fascia and stapler line's over-sewn running suture. RESULTS: Group A (2011-2014) included 1332 LSG, 16 SS were registered (1.2%), 7 OS and 9 FS; 3903 LSG included in group B (2015-2019), counting for 37 SS (0.95%), 27 OS and 10 FS. A statistically significant difference between the 2 groups was observed for the FS incidence (P=0.03), while it was non-significant for the OS (P=0.52) and the total number of SS (P=0.43). The endoscopic approach was used in forty-eight SS (90.5%) with a successful rate of 83%, while specifically for the FS it was 100%; only one complication was registered during endoscopic treatment, that required further surgical solution. CONCLUSIONS: Fixation of the gastric tube to the prepancreatic fascia and stapler line's over-sewn running suture during LSG, introduced lately, are beneficial in preventing the postoperative functional stenosis of the LSG, contributing to the improvement of the patient's quality of life.

Short Term Outcomes of Using Fecal Immunochemical Test for a Pilot Colorectal Cancer Screening Program. A Single Center Study on 3024 Consecutive Patients.

Background: In Romania, colorectal cancer does not benefit yet from a national screening program. In order to decrease the harm and burden of colorectal cancer (CRC), opportunistic programs relying on endoscopy has been adopted by each centre according to its capacity. A colorectal cancer (CRC) screening programme based on faecal immunochemical test (FIT) was launched at Ponderas Academic Hospital (PAH) in 2019. Aim: The present study analyses the outcomes after the first 1500 tests in the PAH-FIT-CRC Screening Program. We have also aimed to compare the efficiency of the FIT testing program with the screening colonoscopies performed in our Center, withing the same time interval (2019). Methods: The test was recommended in asymptomatic patients over 45 years, and it was followed by a colonoscopy when the test results were positive. Furthermore, we performed a retrospective observational study gathering data from all the consecutive patients prospectively included in the respective databases of our hospital, comparing the efficacy of the two colorectal cancer screening methods (FIT versus colonoscopy). Results: Between 01.01.2019 and 01.01.2020, 1524 screening colonoscopies were performed, and the resulting data were compared with those obtained in the FIT group (1500 FIT tests freely distributed). In the screening colonoscopy group, the polyp detection rate was 38.98% and 22 (1.44%) adenocarcinomas were identified. In the FIT group, the FIT uptake rate was 71% with a positivity rate of 21.7%. The colonoscopy compliance rate for positive FIT patients was 29.4%, with only 2 adenocarcinomas detected. Conclusions: Following data analysis, the need for improvement of uptake rate and colonoscopy compliance rate was suggested, due to the lower acceptance of FIT tests and colonoscopies, especially among men. Moreover, special efforts should be made in order to improve quality indicators for screening colonoscopies (especially adenoma detection rate) with the purpose of decreasing interval CRC.

SRED-ARCE Recommendations for Minimally Invasive Interventions During the COVID-19 Pandemic in Romania.

The Romanian Society of Digestive Endoscopy (SRED) and the Romanian Association of Endoscopic Surgery (ARCE) have decided to establish a joint working group to elaborate specific recommendations for organizing the diagnostic and the minimally invasive interventional procedures, in the context of the COVID-19 pandemic. The recommendations are based on the guidelines of the international societies of endoscopy and gastroenterology (ESGE / BSG / ASGE / ACG / AGA), respectively endoscopic surgery (EAES SAGES) (4-8), on the experience of countries severely affected by the pandemic (Italy, France, Spain, USA, Germany, etc.) and they will be applied within the limits of measures imposed at local and governmental level by the competent authorities. On the other hand, these recommendations should have a dynamic evolution, depending on the upward or downward trend of the COVID-19 pandemic at regional and local level, but also according to the findings of professional and academic societies, requiring regular reviews based on the publica tion of further recommendations or international clinical trials. The objectives of the SRED and ARCE recommendations target the endoscopic and laparoscopic surgery activities, to support their non discriminatory used for diagnostic or therapeutic purposes, pursuing the demonstrated benefits of these procedures, in safe conditions for patients and medical staff.

Adhesiolysis-Related Challenges for Laparoscopic Procedures after Ventral Hernia Repair with Intraperitoneal Mesh.

Background: Laparoscopic procedures in patients with history of abdominal surgery can be challenging due to the unknown risk of postoperative adhesions (POA). The intraperitoneal onlay mesh procedures (IPOM) are frequently used for open or laparoscopic repair for incisional and ventral hernia. The risk of PoA can be increased in these patients, thus, any further laparoscopic exploration might be considered difficult. The aim of our study is to analyze the adhesiolysis-related challenges and complications in patients requiring laparoscopic surgery after IPOM ventral hernia repair. Methods: All the patients who underwent any laparoscopic procedure after open or video-assisted IPOM ventral hernia repair in Ponderas Academic Hospital from May 2011 to December 2018, were retrospectively analyzed. Two trained experts reviewed all video recordings and collected data on surgical history, adhesion location and density, dissection difficulty, interval time to release adhesions from the mesh and complications. Results: Twenty-nine patients were included into the study. There were 17 females, mean age of 58.0 +- 14.5 years, mean BMI of 28.7 +- 7.0 Kg/m2 and a median number of abdominal surgeries of 3/ patient. Risk factors for adhesion formation, other than the mesh itself were found in16 patients. The median time from the last IPOM procedure to the laparoscopic exploration was 26 months and it was related to the hernia repair technique in 21 patients and indicated for other pathologies in 8 patients.Adherences to the mesh were found in the majority of the cases (96%).The mean score of surface adhesion and adhesion tenacity was 4.0 +- 1.7 and 3.0 +- 0.8, respectively. The median time to complete the adhesiolysis to the mesh was 22 minutes. Small bowel was open during the dissection in six patients. Mesh migration was encountered in two. There were three conversions to open surgery and one to robotic surgery. History of peritonitis and septic complications at the last surgery were significantly associated with a higher rate of conversion. One surgical site infection and no mesh infection were encountered. The median postoperative hospital stay was 4 days. The 30-day postoperative mortality was nil. The median postoperative follow-up was 13 months. There are 3 recurrent incisional hernias. Conclusions: The study demonstrates that laparoscopic approach after previous IPOM is feasible but challenging. Adherences to the mesh are expected in the majority of the cases. History of peritonitis, a large number of open abdominal procedures, and septic complication at last surgery correlate with a high difficulty of adhesiolysis.

Intraoperative cardiovascular response of natural orifice transluminal endoscopic surgery versus laparoscopy: A comparative animal study.

BACKGROUND: Natural orifice transluminal endoscopic surgery (NOTES) emerged as a new alternative method in minimally invasive techniques. Although a very small number of studies have compared the physiologic response in NOTES to laparoscopy, the results remain controversial. AIM: This experimental animal study aims to evaluate the intraoperative cardiovascular and respiratory effects of pure transluminal natural orifice surgery and conventional laparoscopy. MATERIALS AND METHODS: Twenty female pigs (Sus scrofa domesticus) equally divided into two study groups were assigned to either pure natural orifice transluminal endoscopic techniques (Group 1) or conventional laparoscopic surgery (Group 2) and monitored intraoperatively in terms of heart rate (HR), systolic blood pressure (SBP) and O2saturation (SpO2) for 1 h. Both groups underwent simple surgical procedures such as gastrojejunostomy, oophorectomy and adnexectomy. RESULTS: All procedures were successfully completed. The findings indicated statistically significant differences between SBP (P = 0.0065) and SpO2(P = 0.027) in the two groups at the beginning of the interventions. HR showed significant differences during the last 20 min of the interventions (min 40 and 45; P < 0.001). For the whole procedure (from the beginning of the intervention to 60 min interval), HR, SBP and SpO2values showed no statistical difference. CONCLUSIONS: Although significant differences in terms of HR, mean blood pressure and SpO2were noted at specific intervals during surgery, no real variance of the cardiovascular parameters was observed when considering the entire procedure. Therefore, NOTES seems to be a safe approach with minimally intraoperative cardiovascular and respiratory implications.

Symptomatic Stenosis after Laparoscopic Sleeve Gastrectomy - Incidence and Management in a High-Volume Bariatric Surgery Center.

Background: Owing to the increased use of laparoscopic sleeve gastrectomy (LSG) as a metabolic procedure, a rarely associated complication, the Symptomatic Stenosis (SS) will be more often encounter. The objective of this study is to establish a safe and effective management of SS after LSG. Methods: We have analyzed all the patients with SS after LSG treated in Ponderas Academic Hospital from 2011 to 2018. The information was retrospectively extracted from a prospectively maintained database. Laparoscopy and/or endoscopy were used to treat the organic or functional SS. The procedure's outcomes (effectiveness and complications) were analyzed. Results: Out of the 4304 patients with LSG 47 (1.1%) patients were identified with SS after LSG. The incidence is depending on the LSG technique. Other 4 patients referred to our center have been added. Surgery was the first choice in 9 cases with only 33.3% success rate. For the 46 patients referred to endoscopy there have been 79 pneumatic dilation with an average of 1.7+- 1.1 per patient. We have encountered 1 perforation but any hemorrhage or death. Follow-up rate was 93.5%. Over all, the success rate of endoscopic dilatations was 90.7%. Conclusion: The incidence of SS is low. Endoscopic pneumatic dilation is a safe and effective procedure and should be the front line choice in the management of SS after LSG.

Corrosion of carbon steel by bacteria from North Sea offshore seawater injection systems: laboratory investigation.

Influence of sulfidogenic bacteria, from a North Sea seawater injection system, on the corrosion of S235JR carbon steel was studied in a flow bioreactor; operating anaerobically for 100days with either inoculated or filtrated seawater. Deposits formed on steel placed in reactors contained magnesium and calcium minerals plus iron sulfide. The dominant biofilm-forming organism was an anaerobic bacterium, genus Caminicella, known to produce hydrogen sulfide and carbon dioxide. Open Circuit Potentials (OCP) of steel in the reactors was, for nearly the entire test duration, in the range -80045), suggested pitting on steel samples within the inoculated environment. However, the actual degree of corrosion could neither be directly correlated with the electrochemical data and nor with the steel corrosion in the filtrated seawater environment. Further laboratory tests are thought to clarify the noticed apparent discrepancies.

Analysis of alkyl polyglucosides in industrial products by capillary electrophoresis with pulsed amperometric detection.

Pulsed amperometric detection following micellar electrokinetic chromatography has been applied successfully to the direct detection of alkyl polyglucosides (APGs) in shampoos and other industrial products without prior conversion to highly absorbing or fluorescing derivatives. For electrochemical detection, it is necessary to dissociate the hydroxyl groups of the APGs. Thus, we used 0.1 M NaOH in the outlet vial to dissociate the APGs. The main problems associated with the combination of electrochemical detection and capillary electrophoresis are the need to isolate the detector from the electric field used in the capillary electrophoresis separation and the difficulty of aligning the working electrode with the end of the capillary. To overcome these problems, a simple capillary-electrode holder was constructed. This holder automatically aligns the capillary and the electrode in a wall-jet configuration without the aid of micropositioners and facilitates the replacement of electrodes and capillaries without reconstruction of the entire capillary/electrode setup. Special microcylindrical gold electrodes have been produced by sealing 300-microm-diameter gold wire into borosilicate-glass capillaries.

Redox competition mode of scanning electrochemical microscopy (RC-SECM) for visualisation of local catalytic activity.

In order to locally analyse catalytic activity on modified surfaces a transient redox competition mode of scanning electrochemical microscopy (SECM) has been developed. In a bi-potentiostatic experiment the SECM tip competes with the sample for the very same analyte. This leads to a current decrease at the SECM tip, if it is positioned in close proximity to an active catalyst site on the surface. Specifically, local catalytic activity of a Pt-catalyst modified sample with respect to the catalytic reduction of molecular oxygen was investigated. At higher local catalytic activity the local 02 partial pressure within the gap between accurately positioned SECM tip and sample is depleted, leading to a noticeable tip current decrease over active sites. A flexible software module has been implemented into the SECM to adapt the competition conditions by proper definition of tip and sample potentials. A potential pulse profile enables the localised electrochemically induced generation of molecular oxygen prior to the competition detection. The current decay curves are recorded over the entire duration of the applied reduction pulse. Hence, a time resolved processing of the acquired current values provides movies of the local oxygen concentration against x,y-position. The SECM redox competition mode was verified with a macroscopic Pt-disk electrode as a test sample to demonstrate the feasibility of the approach. Moreover, highly dispersed electro-deposited spots of gold and platinum on glassy carbon were visualised using the redox competition mode of SECM. Catalyst spots of different nature as well as activity inhomogeneities within one spot caused by local variations in Pt-loading were visualised successfully.

Fabrication of a potentiometric/amperometric bifunctional enzyme microbiosensor.

We report the fabrication and functional characterization of a needle-type bifunctional enzyme microbiosensor that has, as technical novelty, simultaneously integrated a potentiometric and amperometric detection of an enzyme-catalyzed reaction at the tip of a pulled glass micropipet. The construction involved immobilizing an enzyme onto the platinized outer tip surface using the precipitation of electrodeposition paint with direct entrapment of the biocomponent in the slowly growing polymer film. Products of enzyme-substrate reaction could then be targeted in a dual-detection mode on one hand with the covered Pt layer at the tip region as amperometric detector and on the other hand with a proton-selective liquid membrane-based potentiometric sensor inside the open pipet tip. Completing and testing bifunctional glucose microsensors demonstrated the functionality of the proposed strategy. Synchronized amperometric and potentiometric detection of the addition of a glucose standard to a buffer solution became evident by observing stepwise increases in the amperometric H2O2 oxidation current and corresponding increases in the potential of the pH-selective sensor, which translates to a local pH decrease around the tip due to hydrolysis of enzymatically formed gluconic acid.

Imaging immobilised ssDNA and detecting DNA hybridisation by means of the repelling mode of scanning electrochemical microscopy (SECM).

The supposed repelling mode of scanning electrochemical microscopy (SECM) allows truly label-free electrochemical recognition of the presence and hybridisation of nucleic acids that are immobilised on conducting DNA chips. Basically, the SECM-based detection of single- and double-stranded DNA profits from the electrostatic repulsion between deprotonated phosphate groups at the backbone of the oligonucleotides and a free-diffusing negatively charged redox mediator (e.g. [Fe(CN)(6)](3-/4-)). In electrolytes of proper pH and ionic strength, this coulomb interaction is heavily influencing the diffusion properties of the mediator in the vicinity of the surface-anchored DNA strands. This charge interaction modulates the diffusional mass transport for the charged redox species in the DNA modified regions, and thus locally decreases the positive feedback currents measured with a SECM tip placed within the electrochemical nearfield of the chip surface. This approach was used to study arrays of synthetic 20-base oligonucleotide probes that were immobilised on monolayer-modified gold surfaces. Evidence is provided that the density of probes, the ionic strength of solution and the tip-to-sample distance have a strong impact on the capability of the repelling mode of SECM to visualise probe spots and hybridisation while the concentration of the chosen mediator did not significantly affect detection.

Scanning electrochemical microscopy (SECM) of nanolitre droplets using an integrated working/reference electrode assembly.

Scanning electrochemical microscopy (SECM) has been performed in the restricted space of nanolitre droplets with a robust and easy-to-handle coaxial electrode assembly centring a Pt microdisk in a circular Ag electrode. Straightforward and reproducible fabrication of the specially designed probe tips was achieved by using Tollens' reaction to chemically deposit a uniform and well-adhering layer of silver on the body of a glass-insulated Pt microdisk electrode. The suitability of the novel dual-electrode SECM tip for measurement in small volumes was evaluated by imaging an array of four Pt band microelectrodes in 500 nL electrolyte.

Ink-jet printing for micropattern generation of laminin for neuronal adhesion.

In order to achieve defined adhesion and neurite outgrowth, the growth substrate must be patterned in an appropriate way. We utilised ink-jet printing by means of a piezo-based microdispenser to create defined line patterns of a polymer with typical dimensions of 100 microm width on glass, silicon, gold and carbon substrates. Vinnapas, a co-polymer of vinyl acetate and ethylene, was mixed with the extracellular matrix protein laminin to achieve neuronal adhesion on the surface of the patterns. It could be demonstrated that the laminin entrapped in the polymer lines can be recognised by a specific antibody. Adhesion of embryonic chicken forebrain neurones is following the prepared lines, and identity of adhering cells could be shown by neurofilament staining. These findings open the route for the generation of complex small neuronal arrays and for the electrochemical investigation of the obtained neuronal matrix.