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Unique occurrence of magnetism is shown, in which magnetism appears ex nihilo, when organic molecules are self-assembled as monolayers on gold substrate. The molecules as well as the substrate, when they stand alone, are diamagnetic. Using a superconducting quantum interference device type magnetometer we obtained direct evidence that close-packed organized thio-organic films adsorbed on gold substrates possess magnetic properties at room temperature. The films studied show very high specific magnetization, up to many tens Bohr magnetons per adsorbed molecule, with a very small hysteresis. It is highly anisotropic and shows almost no temperature dependence. The magnetism observed is related to charge transfer between the organic layer and the metal substrate. Yet, the uniqueness here is that many spins are polarized per adsorbed molecules. The magnetic effect is related to the two dimensional organization of the organic molecules on the metal substrate which might explain the high anisotropy. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Background: Glucagon-like-peptide-1 receptor agonists (G1RA) have gained popularity as a treatment for weight loss in patients who are overweight or obese, but their utilization patterns and impact on candidates for metabolic and bariatric surgery (MBS) remain understudied., Objective: We aimed to investigate the prevalence, characteristics, and outcomes of patients with a history of G1RA utilization among MBS candidates., Setting: Five high-volume MBS centers in Israel., Methods: Data were collected retrospectively from February 1st, 2023, to September 30th, 2023. Demographic, clinical, and treatment data were analyzed to assess a history of G1RA use, associated factors, adverse events, and treatment outcomes., Results: Four hundred thirty-four MBS candidates were included in the study. A history of G1RA utilization was obtained in 275 (63%) MBS candidates, with Liraglutide and Semaglutide being the most commonly used agents. Younger age, type 2 diabetes mellitus, dyslipidemia, and no previous MBS history were associated with a higher rate of G1RA utilization. With these medications, median maximal weight loss was 5.38 kg, and mean duration of use was 19 weeks. Patients using G1RA for ≥6 weeks experienced significantly greater weight loss compared to those using it for shorter periods (6.3 ± 6.43 vs 1.65 ± 1.69; P < .001). GI-related adverse events were reported in 57.8% of patients. Over 95% of patients discontinued G1RA due to insufficient weight loss and/or adverse effects. Patients reaching the maximal recommended dose exhibited significantly greater weight loss versus patients who did not reach it for both Liraglutide (5.9 ± 4.98 kg vs. 3.9 ± 5.53 kg; P = .03) and Semaglutide (6.5 ± 7.8 kg vs. 2.5 ± 3.8 kg; P = .016)., Conclusion: Pre-MBS G1RA utilization and failure are prevalent among MBS candidates. Our study underscores the need for further research to understand the role of G1RA therapy in obesity management and the development of guidelines for its appropriate use in MBS candidates., Competing Interests: Disclosure The authors have no commercial associations that might be a conflict of interest in relation to this article., (Copyright © 2024 American Society for Metabolic and Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

Current management of esophageal carcinoma (EC) involves combining different modalities, offering the opportunity of personalized strategies. This is particularly enticing in the geriatric population, where tailoring treatment modalities remains key to achieve good outcomes in terms of both quality of life and survival. Primary outcomes of our review included (1) evidence on short-term outcomes following esophagectomy, and (2) evidence on long-term outcomes following esophagectomy. Secondary review questions compared outcomes of (1) neoadjuvant treatment versus upfront surgery for locally advanced esophageal carcinoma, (2) endoscopic submucosal dissection versus esophagectomy for early esophageal carcinoma, and (3) definitive radiation with or without chemotherapy versus surgery. Twenty-six articles were included in the review for the main review questions. Our systematic review underscores the need for comprehensive geriatric evaluations to guide decision-making. Despite concerns about perioperative risks, well-selected older patients can derive survival benefits from surgical intervention.

The purpose of this study was to evaluate the quality of life (QoL), early post-operative complications, and hernia recurrence rate following laparoscopic enhanced-view Totally Extra-Peritoneal (eTEP) Rives-Stoppa (RS) for incisional and primary ventral hernia repair. Retrospective review of a prospectively maintained database of all patients undergoing eTEP-RS between 2017 and 2020. Data retrieved included demographics, and clinical and operative variables. QoL was assessed using the EuraHS-QoL scale prior to- and following eTEP-RS. During the study period, 61 patients met the inclusion criteria. Age and BMI were 62 (60.4 ± 13.8) years and 29.7 (30.4 ± 6) kg/m 2 , respectively. Incisional hernia was the most common pathology (n = 40, 65%) followed by primary ventral hernia (n = 21, 35%), with 24 patients (39%) having a previous hernia repair. Diastasis-recti repair was undertaken in 34 patients (55%), a concomitant inguinal hernia was repaired in 6 patients (10%), and 13 patients (21%) underwent transversus abdominis release (TAR). Median follow-up time was 13 months and 15 patients (25%) had at least 2 years of follow-up. Hernia recurrence was found in 4 patients (6.5%). Pre-operative and post-operative EuraHS-QOL questionnaire scores were available for 46 patients (75%) and showed significant improvement in pain (7 vs. 0.5, p < 0.0001; 5 vs. 0.5, p < 0.0001; 5 vs. 1.5; p < 0.006), restrictions (median of 5 vs. 0.5, p < 0.0001; 5 vs. 0, p < 0.0001; median of 5 vs. 1, p < 0.0001, of 6.5 vs. 1.5, p < 0.0001), and cosmetic appearance (8 vs. 4, p < 0.0001). Abdominal wall repair using the eTEP-RS approach significantly improves subjective QoL variables with an acceptable post-operative complications and hernia recurrence rates in a short-term follow-up., (© 2023. Italian Society of Surgery (SIC).)

Background: Bariatric surgery (BS) is the optimal approach for sustained weight loss and may alter donation candidacy in potential donors with obesity. We evaluated the long-term effects of nephrectomy after BS on metabolic profile, including body mass index, serum lipids and diabetes, and kidney function of donors., Methods: This was a single-center retrospective study. Live kidney donors who underwent BS before nephrectomy were matched for age, gender, and body mass index with patients who underwent BS alone and with donors who underwent nephrectomy alone. Estimated glomerular filtration rate (eGFR) was calculated according to Chronic Kidney Disease Epidemiology Collaboration and adjusted to individual body surface area to create absolute eGFR., Results: Twenty-three patients who underwent BS before kidney donation were matched to 46 controls who underwent BS alone. At the last follow-up, the study group showed significantly worse lipid profile with low-density lipoprotein of 115 ± 25 mg/dL versus the control group with low-density lipoprotein of 99 ± 29 mg/dL ( P  = 0.036) and mean total cholesterol of 191 ± 32 versus 174 ± 33 mg/dL ( P  = 0.046). The second control group of matched nonobese kidney donors (n = 72) had similar serum creatinine, eGFR, and absolute eGFR as the study group before nephrectomy and 1 y after the procedure. At the end of follow-up, the study group had significantly higher absolute eGFR compared with the control group (86 ± 21 versus 76 ± 18 mL/min; P  = 0.02) and similar serum creatinine and eGFR., Conclusions: BS before live kidney donation is a safe procedure that could increase the donor pool and improve their health in the long run. Donors should be encouraged to maintain their weight and avoid adverse lipid profile and hyperfiltration., Competing Interests: B.R.Z. received consultation fees from Fresenius, Novartis, and Sanofi, and speaker fees from AstraZeneca. The other authors declare no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Biological and synthetic molecular motors, fueled by various physical and chemical means, can perform asymmetric linear and rotary motions that are inherently related to their asymmetric shapes. Here, we describe silver-organic micro-complexes of random shapes that exhibit macroscopic unidirectional rotation on water surface through the asymmetric release of cinchonine or cinchonidine chiral molecules from their crystallites asymmetrically adsorbed on the complex surfaces. Computational modeling indicates that the motor rotation is driven by a pH-controlled asymmetric jet-like Coulombic ejection of chiral molecules upon their protonation in water. The motor is capable of towing very large cargo, and its rotation can be accelerated by adding reducing agents to the water., (© 2023. The Author(s).)

Purpose: Assess the subjective impact of gastro-esophageal reflux disease (GERD) symptoms on patients undergoing revision from laparoscopic sleeve gastrectomy (LSG) to one-anastomosis gastric bypass (OAGB) using the Reflux Disease Questionnaire for GERD (RDQ) and the GERD-health related quality of life score (GERD-HRQL), prior to- and following conversion., Methods: Patients undergoing revision from LSG to OAGB were prospectively followed between May 2015 and December 2020. Data retrieved included demographics, anthropometrics, previous bariatric history, time interval between LSG and OAGB, weight loss, and co-morbidities. Pre- and post-OAGB RDQ and GERD-HRQL questionnaires were obtained. In the case of sleeve dilatation, sleeve resizing was performed., Results: During the study period, 37 patients underwent revision from LSG to OAGB. Mean ages at LSG and pre-OAGB were 38 ± 11.74 and 46 ± 12.75, respectively. Median follow-up time was 21.5 months (range 3-65). All patients underwent sleeve resizing. RDQ and GERD-HRQL scores were obtained at a median of 14 months (range 3-51) between pre- and post-OAGB. Median RDQ score pre-OAGB vs post-OAGB was significantly reduced (30 (range 12-72) vs 14 (range 12-60), p = 0.007). All 3 parts of the GERD- HRQL questionnaires were significantly reduced between pre-OAGB and post-OAGB: Symptoms (20; 62.5% vs 10; 31.3%, p = 0.012), overall score (15 (0-39) vs 7 (0-28), p = 0.04) and subjective improvement (10; 31% vs 20; 62.5%, p = 0.025)., Conclusion: Conversion of LSG to OAGB showed subjective improvement of GERD symptoms both in RDQ and in GERD-HRQL., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Introduction: Bariatric surgery is an effective tool for weight loss in the obese population, improving and often resolving related co-morbidities such as diabetes and hypertension, reducing overall morbidity and mortality. However, many patients suffer from excess and redundant skin in many areas of their body. Skin excess can cause physical, functional, psychological and aesthetic impairments such as fungal infections and skin rashes, difficulty maintaining personal hygiene, low self-esteem and self-image, social isolation, depression and low quality of life. Areas most commonly affected are the abdomen, upper arms, thighs and breasts. Body contouring surgery (post-bariatric surgery) can resolve health issues related to skin excess, improve quality of life and body image and help maintain weight loss. Since its establishment, the post-bariatric unit has performed 76 post-bariatric surgeries on 56 patients in Assuta Ashdod Hospital (67.1% abdominoplasties, 14.47% thigh-lifts, 10.52% brachioplasties, 5.26% breast surgeries, 2% gynecomastia repairs). In this article, we present the post-bariatric service in Assuta Ashdod Hospital including the pre-and post-operative treatment protocols and results.

Introduction: Accurate early diagnosis of a gastrointestinal anastomotic leak remains a challenge. When an anastomotic leak develops, the electrical properties of the tissue undergoing inflammatory processes change, resulting from the extravasation of inflammatory fluid and cellular infiltration. The method described here intends to provide a novel early anastomotic leak warning system based upon measurable changes in tissue impedance nearby an acute inflammatory process., Methods: A biodegradable Mg-alloy was compared with a nonabsorbable stainless steel (STS) electrode connected to a wireless recording system for impedance measurement. In vitro measurements were made in physiological solutions and small animal (eight mice) and large animal (eight pigs) models with an anastomotic leak simulated by an open colotomy. Measurements were made at 10 mm intervals from the open colon at baseline and up to 120 min comparing these with a sutured colonic wound and normal tissue., Results: In-vitro biodegradable magnesium electrode impedance evaluation showed good sensitivity to different media due to its environmental corrosion properties. The impedance of an acidic environment (1.06 ± 0.02 kΩ for citric acid) was twice that of phosphate-buffered saline (PBS) (0.64 ± 0.008 kΩ) with a distinction between Normal Saline (0.42 ± 0.013 kΩ) and PBS (0.64 ± 0.008 kΩ). This was in contrast to the performance characteristics of the control STS electrodes, where impedance in an acidic environment was lower than saline or PBS (citric acid:0.76 ± 0.01 kΩ versus PBS: 1.32 ± 0.014 kΩ). In a mouse model simulating an anastomotic leak, there was a significant increase in impedance after 120 min when compared with controls (99.7% increase versus 9.6% increase, respectively; P < 0.02). This effect was confirmed in a pig model when relative impedance measurements of the leak and control groups were compared (1.86 ± 0.46 versus 1.07 ± 0.02, respectively; P < 0.027)., Conclusions: Electrophysiological measurement shows diagnostic sensitivity for a gastrointestinal leak with potential clinical utility in the postoperative detection of early intra-abdominal sepsis. Further investigation of biodegradable tissue sensors capable of monitoring an early anastomotic leak is required., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: The increasing prevalence of morbid obesity (MO) results in parallel growth of obesity-associated liver diseases necessitating liver transplantation (LT)., Objective: To examine the feasibility and safety of Roux-en-Y gastric bypass or sleeve gastrectomy in the setting of LT., Methods: This retrospective chart review included the data on all the MO candidates before and after LT who underwent bariatric surgery (BS) in our institution between 04/2013-09/2016. The reported outcomes were weight change and early and late postoperative complications (mean follow-up: 43 ± 11.1 months)., Results: Eighteen MO peri-LT patients (10 females, 8 males, average age 48 years) were included in the study. Ten had cirrhosis (mean Model of End-stage Liver Disease [MELD] score of 12.5 ± 6.42), three underwent concurrent LT and BS (mean MELD score 23.7 ± 0.58), and five had LT (mean of 56 months from LT). The mean percentage of total and excess weight loss was 31% and 81%, respectively. Six of the eight patients with type 2 diabetes mellitus became normoglycemic after BS. Three patients sustained perioperative complications. Two cirrhotic patients died 1 and 4.5 years after BS with decompensation., Conclusions: Bariatric surgery appears to effectively address obesity in cirrhotic and LT patients. The surgical risk is higher than that of the regular BS population., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The efficient optoelectronic properties of photosynthetic proteins were explored in the quest for the fabrication of novel solid biohybrid devices. As most optoelectronic devices function in a dry environment, an attempt was made to fabricate an efficient electronic junction by covalent binding of photosynthetic reaction center proteins to metals, transparent semiconductor polymers, and solid semiconductors that function in a dry environment. The primary stages of photosynthesis take place in nanometric-size protein-chlorophyll complexes. Such is photosystem I (PSI), which generates a photovoltage of 1 V. The isolated PSI generates an absorbed light-energy conversion efficiency of ∼47% (∼23% solar energy) and internal quantum efficiency of ∼100%. The robust cyanobacterial PSI was used in the fabrication of solid-state optoelectronic devices by forming oriented multilayers from genetically engineered cysteine mutants between metal and transparent conducting semiconductor electrodes. Current-voltage measurements of the cells generated diode- and photodiode-like responses in the dark and the light, respectively. The cells were stable for many months in a dry environment. The generation of photocurrent and V oc indicated the formation of good electronic coupling between PSI and the electrodes, which can serve in the fabrication of solid-state biohybrid optoelectronic devices.

Background: Staple-line leaks (SLL) after sleeve gastrectomy (SG) are a rare but serious complication requiring radiologic and endoscopic interventions with varying degrees of success. When failed, a chronic gastrocutaneous fistula forms with decreasing chances of closure with time. Definitive surgical management of chronic SLL after SG include laparoscopic revision to total/subtotal gastrectomy (LTG/LSTG) or a fistulo-jejunostomy (LRYFJ), both with Roux-en-Y reconstruction., Objectives: Comparison of SG revisions to LTG/LSTG versus LRYFJ as a definitive treatment for chronic SLL., Setting: High-volume bariatric unit., Methods: Retrospective review of a prospectively maintained database identified 17 patients with chronic gastric fistula after SG that were revised to either LTG/LSTG or LRYFJ between September 2011 and May 2020. Demographic characteristics, clinical data, quality of life, and laboratory values for both options were compared., Results: Of the 17 conversions, 8 were revised to LTG/LSTG and 9 to LRYFJ. Mean age and body mass index at revision were 36.85 years (range, 21-66 yr) and 29 kg/m 2 (range, 21-36 kg/m 2 ), respectively. Average preoperative endoscopic attempts was 5 (range, 1-16). The overall average operation time of revision was 183 minutes (range, 130-275 min) with no significant difference between either conversion options. Mean follow-up time was 46.5 months (range, 1-81 mo) and was available for 10 patients (58.8%). Food intolerance was significantly better after revision to LRYFJ (n = 6/6, 100% versus n = 1/5, 20%, P < .05). There were no significant differences between revisional procedures and laboratory abnormalities., Conclusion: Laparoscopic revision to LRYFJ is a safe and feasible treatment for chronic SLL., (Copyright © 2020 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

In biological systems, membrane proteins play major roles in energy conversion, transport, sensing, and signal transduction. Of special interest are the photosynthetic reaction centers involved in the initial process of light energy conversion to electrical and chemical energies. The oriented binding of membrane proteins to solid surfaces is important for biotechnological applications. In some cases, novel properties are generated as a result of the interaction between proteins and solid surfaces. We developed a novel approach for the oriented tagging of membrane proteins. In this unique process, bifunctional molecules are used to chemically tag the exposed surfaces of membrane proteins at selected sides of membrane vesicles. The isolated tagged membrane proteins were self-assembled on solid surfaces, leading to the fabrication of dens-oriented layers on metal and glass surfaces, as seen from the atomic force microscopy (AFM) images. In this work, we used chromatophores and membrane vesicles containing protein chlorophyll complexes for the isolation of the bacterial reaction center and photosystem I, from photosynthetic bacteria and cyanobacteria, respectively. The oriented layers, which were fabricated on metal surfaces, were functional and generated light-induced photovoltage that was measured by the Kalvin probe apparatus. The polarity of the photovoltage depended on the orientation of proteins in the layers. Other membrane proteins can be tagged by the same method. However, we preferred the use of reaction centers because their orientation can be easily detected by the polarity of their photovoltages.

Background: The surgical risk of morbidly obese patients is high and even higher for kidney transplant candidates. A BMI > 35-40 kg/m 2 is often a contraindication for that surgery. The safety, feasibility, and outcome of bariatric surgery for those patients are inconclusive., Methods: We conducted a retrospective chart review of prospectively collected data on morbidly obese renal transplant candidates who underwent laparoscopic sleeve gastrectomy (LSG) or laparoscopic Roux-en-Y gastric bypass (LRYGB) in our institution between January 2009 and September 2017. The reported outcome included body weight and graft status after a mean follow-up of 47 months (range 0.5-5 years)., Results: Twenty-four patients (8 females, 16 males, average age 54 years, average preoperative BMI 41 kg/m 2 [range 35-51]) underwent LSG (n = 17) or LRYGB (n = 7). Sixteen of them (67%) proceeded to kidney transplantation. Of the 8 pre-transplant and post-bariatric surgery patients, 5 are on the waitlist, and 2 patients died (one of staple line leakage, and one from sepsis unrelated to the bariatric surgery). The average time from bariatric surgery to transplantation was 1.5 years (range 1 month to 4.3 years). The average pre-transplantation BMI was 28 kg/m 2 (range 19-36). The mean percentage of excess weight loss was 66% (n = 21), and the total percentage of weight loss was 29% (n = 21). Comorbidities (type 2 diabetes, hypertension, and dyslipidemia) improved significantly following both surgical approaches., Conclusions: LSG and LRYGB appear to effectively address obesity issues before kidney transplantation and improve surgical access. Morbidly obese transplant candidates would benefit from prior bariatric surgery.

Background: Data on the benefits of bariatric surgery for morbid obesity among kidney transplant recipients are scarce., Objective: To examine the effect of bariatric surgery on graft function and survival and on obesity-related co-morbidities., Setting: University hospital., Methods: This case-control study used retrospectively collected data of all kidney recipients who underwent bariatric surgery in our institution between November 2011 and August 2016 (n = 30, 11 females). Nonbariatric operated kidney recipients matched for age, sex, and time elapsed since transplantation served as controls (n = 50, 23 females). Main outcomes were renal function, graft loss events, mortality, and obesity-related co-morbidities., Results: The mean follow-up duration was 2.4 ± 1.3 years for both groups. At final follow-up, there was an increase in estimated glomerular filtration rates for the bariatric surgery group, and a decrease for the controls (13.4 ± 19.9 and -3.9 ± 15.8 mL/min/1.73 m 2 , respectively, P < .001). The chronic kidney disease classification improved in 9 bariatric surgery group patients and in 6 controls (P = .1). Two patients in the bariatric surgery group and 6 controls died. Total death or graft function loss during the follow-up was 6.7% and 16.7%, respectively (P = .3). The total numbers of co-morbidities and medications were lower in the bariatric surgery patients (-.7 and -2, respectively) and higher in the controls (+.3 and +1.1; P < .001) at study closure., Conclusions: There was an improvement in renal function, graft survival, and obesity-related co-morbidities among kidney transplant recipients who underwent bariatric surgery compared with those who did not. These findings support bariatric surgery in this population and warrant prospective studies., (Copyright © 2019 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

The surgical risk of transplanted patients is high, and the modified gastrointestinal anatomy after bariatric surgery (BS) may lead to pharmacokinetic alterations in the absorption of immunosuppressive drugs. Data on outcomes of BS and the safety and feasibility of maintaining immunosuppression and graft safety among solid organ transplanted patients are scarce. In the current study, weight loss, improvement in comorbidities, and changes in dosage and trough levels of immunosuppression drugs before and after BS were analyzed for all transplanted patients who underwent laparoscopic sleeve gastrectomy (LSG) or laparoscopic Roux-en-Y gastric bypass (LRYGB) in our institution between November 2011 and January 2017. Thirty-four patients (13 females, 21 males, average age 53 years) were included in the study. A successful weight loss (>50% excess weight loss in 28 of them [82%]) was recorded at the last follow-up. Comorbidities improved significantly. Immunosuppressive stability increased from 39% to 47% among all patients. The tacrolimus blood trough levels declined slightly, but remained within therapeutic range. These data suggest that LSG and LRYGB ensure good immunosuppressive maintenance together with significant weight loss and improvement in comorbidities without serious graft rejection or dysfunction. The surgical risk is higher than in the regular BS population., (© 2018 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Background: Gastroesophageal reflux disease and inadequate weight loss (IWL) are long-term complications of laparoscopic sleeve gastrectomy (LSG) and indications for a laparoscopic conversion to an alternative bariatric procedure. The aim of this study is to report the long-term outcomes of biliopancreatic diversion with a duodenal switch (DS) or a Roux-en-Y gastric bypass (RYGB) as conversion procedures for weight loss failure after LSG., Methods: The data of all patients who underwent post-LSG conversion to either a RYGB or a DS at our institution between November 2006 and May 2016 was retrospectively analyzed. Included were all patients with > 1-year follow-up who were operated due to IWL or weight regain. Patients with the indication of reflux were excluded., Results: Sixty-six patients underwent conversion from LSG to RYGB, DS, or one-anastomosis gastric bypass during the study period. There were 21 revisions to DS and 18 to RYGB that met the inclusion criteria. The respective weight and body mass index (BMI) before and after LSG were 125 and 110 kg and 46 and 40.5 kg/m 2 in the RYGB group and 148 and 126 kg and 53.7 and 46 kg/m 2 in the DS group. At the last follow-up (> 2 years), 15 RYGB patients had a reduction in BMI of 8.5-31.9 kg/m 2 and 18 DS patients had a reduction in BMI of 12.8-31.9 kg/m 2 . The mean follow-up was 48.5 months (range 24-76). All comorbidities improved or underwent complete remission., Conclusion: Conversion from SG to RYGB or DS is an efficient and effective treatment for IWL and improvement of comorbidities. Further studies are warranted to evaluate long-term weight regain.

Molecule-plasmon interactions have been shown to have a definite role in light propagation through optical microcavities due to strong coupling between molecular excitations and surface plasmons. This coupling can lead to macroscopic extended coherent states exhibiting increment in temporal and spatial coherency and a large Rabi splitting. Here, we demonstrate spatial modulation of light transmission through a single microcavity patterned on a free-standing Au film, strongly coupled to one of the most efficient energy transfer photosynthetic proteins in nature, photosystem I. Here we observe a clear correlation between the appearance of spatial modulation of light and molecular photon absorption, accompanied by a 13-fold enhancement in light transmission and the emergence of a distinct electromagnetic standing wave pattern in the cavity. This study provides the path for engineering various types of bio-photonic devices based on the vast diversity of biological molecules in nature.

Background: The Silastic ring vertical gastroplasty (SRVG), a newer modification of Mason's vertical banded gastroplasty (VBG), was the restrictive procedure of choice for many bariatric surgeons before the advent of the laparoscopic adjustable gastric banding. However, a high rate of reoperations for failure and severe complications was reported in long-term studies. Around 50% of the patients underwent conversion to other bariatric procedures., Objectives: The aim of this study is to report our experience in laparoscopic conversion of failed VBG and SRVG to biliopancreatic diversion (BPD)., Settings: The setting of the study was at the University hospital., Methods: Between March 2010 and July 2013, 12 patients underwent laparoscopic conversion of VBG and SRVG to BPD. Using a prospectively collected database, we analyzed their data and outcomes., Results: Eighty-six percent of the conversions were successfully completed laparoscopically. The mean operative time was 220 min. There was no mortality. Perioperative complications occurred in four patients (33%). One (9%) late complication, an adhesional small bowel obstruction, was encountered later than 30 days postoperatively. The follow-up rate was 100%, but only three patients reached 3 years at the time of this writing. At a mean follow-up of 19 (3-40) months, the mean body mass index (BMI) decreased from 45.3 to 27.8 kg/m2. Percent excess weight loss (EWL) was 65.7, and 86.3% at 1 and 3 years, respectively., Conclusion: Laparoscopic conversion of failed VBG to BPD is feasible and effective in further reducing weight in morbidly obese patients. Weight loss continues beyond the first postoperative year. However, the complication rate is much higher than in the primary procedure.

Introduction: Surgical antibiotic prophylaxis (AP) guidelines balance the need to prevent infection with the risks of adverse drug effects. Our aim was to assess compliance with AP guidelines., Methods: A retrospective study was performed in a pediatric medical center. Included were patients aged 0 to 18 years that underwent clean-contaminated surgery during a 1-year period (2008-2009) and required AP. Compliance with four AP bundle guidelines was evaluated. Risk factors for noncompliance were identified using univariate and multivariate analyses., Results: AP was given to 239 of 247 (96.8%) of patients. Complete compliance with AP guidelines was achieved in 16 of 247 (6.5%) patients. Compliance with guidelines for appropriate antibiotic, drug dose, correct timing, and treatment duration were found in 97.1, 52.2, 31.9, and 35.9% of patients, respectively. Multivariable analysis showed that inappropriate timing was associated with age ≥ 4 years (p = 0.002), urgent surgery (p = 0.0018), surgical department AP administration (p = 0.0001), and night-time surgery (p = 0.015). Incorrect AP dose was associated with presence of comorbidities (p = 0.006). No risk factor was related to incorrect AP duration., Conclusions: We have found a low rate of full compliance with AP guidelines. AP should only be given in the operating room. Increased awareness to AP guidelines is needed., (Georg Thieme Verlag KG Stuttgart · New York.)

Background: Failed sleeve gastrectomy (SG), defined by inadequate weight loss or weight regain, can be treated by a laparoscopic conversion to a biliopancreatic diversion with duodenal switch (DS) or a Roux-en-Y gastric bypass (RYGB). We report the outcomes of these procedures after SG failure., Methods: All patients who underwent DS (n=9) or RYGB (n=10) due to inadequate weight loss or weight regain between December 2006 and November 2012 after a failed SG were enrolled., Results: The mean pre-SG weight and body mass index (BMI) for the DS and RYGB patients were 143±36 kg and 51.5±11 kg/m2 and 120±26 kg and 44.5±5 kg/m2, respectively. The interval between the SG and the conversion to DS and to RYGB was 27±18 months and 36±17 months, respectively. The operation time and hospital stay were 191±64 minutes and 4.3±2.4 days for DS, and 111±37 minutes and 3.1±1.1 days for RYGB. At reoperation, the weight, BMI and percentage of excess weight loss (%EWL) were 113±22 kg, 43±6 kg/m2 and 28±16.5% and 107±27.5 kg, 40±5.7 kg/m2 and 25±12.7% (all P>.05), for the DS and RYGB, respectively. None of the patients were lost to follow-up. The post-DS weight, BMI, and %EWL were 84±19 kg, 30.7±7.4 kg/m2, and 80±40%. The post-RYGB weight, BMI, and %EWL were 81±21 kg, 30.2±4.8 kg/m2, and 65.5±34% (all P>.05)., Conclusion: DS and RYGB are feasible and effective operations after a failed SG. The DS yields a greater weight loss. The mechanism of failure should guide selection of the second procedure., (Copyright © 2015 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

Photosystem I (PSI) is one of the most studied electron transfer (ET) systems in nature; it is found in plants, algae, and bacteria. The effect of the system structure and its electronic properties on the electron transfer rate and yield was investigated for years in details. In this work we show that not only those system properties affect the ET efficiency, but also the electrons' spin. Using a newly developed spintronic device and a technique which enables control over the orientation of the PSI monolayer relative to the device (silver) surface, it was possible to evaluate the degree and direction of the spin polarization in ET in PSI. We find high-spin selectivity throughout the entire ET path and establish that the spins of the electrons being transferred are aligned parallel to their momenta. The spin selectivity peaks at 300 K and vanishes at temperatures below about 150 K. A mechanism is suggested in which the chiral structure of the protein complex plays an important role in determining the high-spin selectivity and its temperature dependence. Our observation of high light induced spin dependent ET in PSI introduces the possibility that spin may play an important role in ET in biology., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Photosynthesis is used by plants, algae and bacteria to convert solar energy into stable chemical energy. The initial stages of this process--where light is absorbed and energy and electrons are transferred--are mediated by reaction centres composed of chlorophyll and carotenoid complexes. It has been previously shown that single small molecules can be used as functional components in electric and optoelectronic circuits, but it has proved difficult to control and probe individual molecules for photovoltaic and photoelectrochemical applications. Here, we show that the photocurrent generated by a single photosynthetic protein-photosystem I-can be measured using a scanning near-field optical microscope set-up. One side of the protein is anchored to a gold surface that acts as an electrode, and the other is contacted by a gold-covered glass tip. The tip functions as both counter electrode and light source. A photocurrent of ∼10 pA is recorded from the covalently bound single-protein junctions, which is in agreement with the internal electron transfer times of photosystem I.

Control over the T(c) value of high-T(c) superconductors by self-assembled monolayers is demonstrated (T(c) = critical temperature). Molecular control was achieved by adsorption of polar molecules on the superconductor surface (see scheme) that change its carrier concentration through charge transport or light-induced polarization., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The photosystem I (PS I) protein is one of nature's most efficient light harvesting complexes and exhibits outstanding optoelectronic properties. Here we demonstrate how metal nanoparticles which act as artificial antennas can enhance the light absorption of the protein. This hybrid system shows an increase in light absorption and of circular dichroism over the entire absorption band of the protein rather than at the specific plasmon resonance wavelength of spherical metal nanoparticles (NPs). This is explained by broad-resonant and nonresonant field enhancements caused by metal NP aggregates, by the high dielectric constant of the metal, and by NP-PS I-NP antenna junctions which effectively enhance light absorption in the PS I.

We optoelectronically functionalize carbon nanotubes (CNTs) with the photosynthetic reaction center photosystem I (PSI) according to three different on-chip chemical routes. The PSI is bound to the CNTs via covalent, hydrogen, or electrostatic bonds. Our approach allows the electrical contact of single PSI-CNT hybrid systems where the orientation of the PSI with respect to the CNTs depends on the binding mechanism. Our data are consistent with the interpretation that if the PSI is anchored with its internal electron transport path perpendicular to CNTs, the optical excitation of the PSI leads to an enhanced photoconductance of the hybrid system.

The photoconductance properties of photosystem I (PSI) covalently bound to carbon nanotubes (CNTs) are measured. We demonstrate that the PSI forms active electronic junctions with the CNTs, enabling control of the CNTs' photoconductance by the PSI. In order to electrically contact the photoactive proteins, a cysteine mutant is generated at one end of the PSI by genetic engineering. The CNTs are covalently bound to this reactive group using carbodiimide chemistry. We detect an enhanced photoconductance signal of the hybrid material at photon wavelengths resonant to the absorption maxima of the PSI compared to non-resonant wavelengths. The measurements prove that it is feasible to integrate photosynthetic proteins into optoelectronic circuits at the nanoscale.

An extremely fast electron transfer through an electronically coupled junction between covalently bound oriented photosynthetic reaction center protein photosystem I (PS I) and n-GaAs was measured by time-resolved photoluminescence. It was found that the n-GaAs band edge luminescence intensity increased by a factor of 2, and the fast exponential decay constant was increased by a factor of 2.6 following the PS I self-assembly. We attribute this to picosecond electron transfer from the PS I to the n-GaAs surface states.