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Background Laparoscopic sleeve gastrectomy (LSG) has become the preferred bariatric procedure in many countries. However, there is one shortcoming of LSG in the long-term follow-up, and this is the onset of gastro-esophageal reflux disease (GERD) and erosive esophagitis (EE). Conversion to Roux-en-Y gastric bypass (RYGB) is considered an option in patients unresponsive to medical therapy. Currently, there is no evidence of EE improvement or resolution after conversion surgery. In this study, we objectively evaluate the effectiveness of RYGB in management of EE with upper endoscopy (EGD) to identify the significant variables in patients with GERD symptoms post LSG refractory to medical therapy and require conversion surgery. Methods Over a period of 11 years (2008–2019) at Singapore General Hospital, we retrospectively reviewed a prospectively collected database of a cohort of patients whom had conversion surgery to RYGB for refractory GERD and EE after LSG. Patient’s endoscopic findings and demographic and anthropometric data were analyzed. Results We identified a total of 14 patients who underwent LSG to RYGB conversions for endoscopic proven erosive esophagitis in our unit during the study period. Eight patients (57.1%) had concurrent hiatal hernia repaired. Nine (64.3%) patients were females. The median age of patients in this cohort was 44 (range 30–61) years. Mean weight and BMI were 87.7 kg (± 19.2) and 32.8 (± 3.09) kg/m2, respectively, on the day of conversion surgery. The median time between LSG and revision to RYGB was 36 (range 6–68) months. Seven patients (50%) had complete resolution of GERD symptoms after conversion, and 6 patients (42.9%) had partial resolution. Six out of 7 patients had complete resolution of EE. There were 4 anastomotic strictures (28.6%). Older patients, Indian ethnicity, present of hiatal hernia and lower weight loss after initial LSG were more likely to undergo conversion surgery. Conclusion Conversion to RYGB after LSG is clinically relevant and may be a feasible solution if patients have ongoing GERD refractory to medical therapy. Ninety-three percent of our patients achieved complete resolution of their GERD symptoms and significant improvement of erosive esophagitis with significant weight loss after conversion. This study has important implications as LSG is increasingly being performed and a proportion of these will need revision surgery for various reasons, particularly GERD which is extremely prevalent.

Palmar lip fractures at the base of the middle phalanx are well-regarded as a difficult condition to treat, with many treatment strategies leading to pain and impairment. Hemi-hamate resurfacing arthroplasty for the proximal interphalangeal joint surface has been described in the literature as a surgical option in the management of this fracture type. This case series aims to describe our institution’s experience with hemi-hamate arthroplasty for this type of fracture. Six patients from a single institution who underwent hemi-hamate arthroplasty for treatment of impacted dorsal fracture dislocations of the base of the middle phalanx between 2014 and 2018 were retrospectively reviewed. Four patients were managed at a time frame greater than 100 days, with a range between 32 and 50% of articular joint involvement. Functional outcomes and pain scores following hemi-hamate arthroplasty in both acute and chronic presentations resulted in adequate range of motion and grip strength, with minimal pain at either fracture or donor site. No cases of non-union were seen in our cohort. Based on our experience, hemi-hamate arthroplasty is a viable option in the management of intra-articular fracture dislocations of the base of the middle phalanx. Level of evidence: Level IV, therapeutic study.

Anastomotic leak following Ivor Lewis oesophago-gastrectomy is a major complication with high morbidity and mortality. We report our experience with three such cases where endoscopically deployed double pigtail stents (DPT) were used to help manage the leaks. Methods Three patients from October 1, 2019 to February 29, 2020 experienced leakage from the oesophago-gastric anastomosis following minimally invasive Ivor Lewis oesophago-gastrectomy. These occurred on post-operative day 9, day 29 and day 7 respectively. All cases were managed with endoscopic deployment of double pigtail stents along with other adjunctive measures. Results To date all patients remain alive, with sepsis under control. One of the patients had been able to have his double pigtail stent removed at six weeks and he has been able to commence adjuvant chemotherapy. Another patient had a follow-up contrast study one week after DPT insertion which showed no further contrast extravasation and was able to recommence oral intake. The third patient has a left empyema (managed conservatively with a combination of internal DPT and external pigtail drainage) which is gradually resolving. Conclusion Endoscopically deployed DPTs are a useful tool in the armamentarium for managing oesophago-gastric anastomotic leaks in selected patients following Ivor Lewis oesophago-gastrectomy. They are advantageous in that stent migration does not appear to be an issue, nor is there any problem with leakage around the stent. Patients are mostly able to restart oral intake soon after insertion of DPTs. This reduces the morbidity associated with these anastomotic leaks, and reduces the number of interventions needed.

Temperature and heat are difficult concepts for children to grasp due to their abstractness. An image-to-writing approach, guided by the visualisation practices of scientists, was designed to engage elementary students with constructing images to represent their ideas about phenomena and translating these images into text using scientific terminologies. Taking a quasi-experimental approach, the experimental group students received inquiry-based instruction based on the image-to-writing approach, while the control group students received a mix of direct instruction and inquiry activities without explicit focus on multimodal representations. An instrument consisting of four free response questions was developed and administered to 129 primary 4 students (aged 9–10) before (pre-test) and after (post-test) instruction to determine their conceptual understanding and representational competences. ANCOVA showed that students in the experimental group perform significantly better than those in the control group in their conceptual understanding. Further analysis revealed that a larger percentage of students in the experimental group demonstrated higher levels of conceptual understanding after instruction, compared to the control group for more complex phenomena, even though both groups showed similar levels of representational competences. The findings suggest that an image-to-writing approach can help students develop deeper conceptual understanding as well as use representations to demonstrate their conceptual understanding. The use of images could have helped students in their thinking and learning of complex phenomena, which allowed them to better convey their understanding of the concepts.

There is concern over how to survey the remnant upper gastrointestinal tract, as well as what to do if a patient subsequently develops an upper gastrointestinal cancer following bariatric surgery. We hereby report a case of gastric cancer arising 8 years after a laparoscopic sleeve gastrectomy (LSG). The patient, a 42 year-old woman, was diagnosed with a gastric cancer via esophagogastroduodenoscopy (EGD). As such, she underwent a laparoscopic total gastrectomy with lymphadenectomy. The final histopathology was that of a poorly differentiated adenocarcinoma with signet-ring cells without lymph node metastases (staging pT4aN0). The background gastric mucosa displayed no Helicobacter pylori. There have only been a few reported cases of gastric cancer after sleeve gastrectomy. Nevertheless, it may be wise to consider performing EGD at regular intervals after bariatric surgery, especially in Asia. In this regard, LSG holds an advantage over Roux-en-Y gastric bypass with respect to the feasibility of surveillance of the remnant stomach.

Significance In a world that strives to accommodate population growth and climate pattern changes, there is a compelling need to develop new technologies to enhance agricultural output while minimizing inputs and mitigating their effects on the environment. In this study, we describe a biomaterial-based approach to engineer the microenvironment of seeds through the preservation and delivery of plant growth promoting rhizobacteria (PGPRs) that are able to fix nitrogen and mitigate soil salinity. PGPRs are encapsulated in silk–trehalose (ST) coatings that achieve bacterial preservation and delivery upon sowing. The biomaterial choice is inspired by a recent finding that a combination of proteins and disaccharides is key for anhydrobiosis. This simple technology is effective to boost seed germination and mitigate soil salinity., Human population growth, soil degradation, and agrochemical misuse are significant challenges that agriculture must face in the upcoming decades as it pertains to global food production. Seed enhancement technologies will play a pivotal role in supporting food security by enabling germination of seeds in degraded environments, reducing seed germination time, and boosting crop yields. So far, a great effort has been pursued in designing plants that can adapt to different environments and germinate in the presence of abiotic stressors, such as soil salinity, heat, and drought. The technology proposed here seeks a different goal: To engineer the microenvironment of seeds by encapsulation, preservation, and precise delivery of biofertilizers that can boost seed germination and mitigate abiotic stressors. In particular, we developed a biomaterial based on silk fibroin (S) and trehalose that can be mixed with rhizobacteria and applied on the surface of seeds, retrofitting currently used techniques for seed coating, i.e., dip coating or spray drying. A micrometer thick transparent robust coating is formed by material assembly. The combination of a polymorphic protein as S and of a disaccharide used by living systems to tolerate abiotic stressors provides a beneficial environment for the survival of nonspore forming rhizobacteria outside the soil and in anhydrous conditions. Using Rhizobium tropici CIAT 899 and Phaseolus vulgaris as working models, we demonstrated that rhizobacteria delivered in the soil after coating dissolution infect seedlings’ roots, form root nodules, enhance yield, boost germination, and mitigate soil salinity.

Data on attitudes and perceptions towards obesity are lacking in Asia. Participants who attended an obesity public forum were surveyed concerning obesity and its treatment options. Although obesity is generally accepted as a disease with biological underpinnings such as hormonal imbalances and slow metabolic rate, it is also regarded as an issue of personal responsibility. 65.1% believed that weight-loss medications are dangerous. 20.6% thought that pharmacotherapy is effective for weight loss, whereas 41.1% were unsure. Most believed that bariatric surgery could improve health (81.9%) and diabetes control (74.0%) although 64.1% were unsure of its risks.

Laparoscopic sleeve gastrectomy (LSG) has become the preferred bariatric procedure in many countries. However, there is one shortcoming of LSG in the long-term follow-up and this is the onset of GERD and erosive esophagitis (EE). Current evidence of the effect of SG on GERD did not consolidate to a consensus. In this study, we objectively evaluate the incidence of EE 1 year post-LSG with upper endoscopy (EGD) and try to identify the significant variables and possible underlying mechanisms of the EE post-LSG. Over a period of 5 years (2011–2016) at Singapore General Hospital, we retrospectively reviewed a prospectively collected database of a cohort of patients whom had LSG by a single surgeon who routinely performed EGD pre-operative and 1 year post-operative to assess EE and hiatal hernia. Patient’s endoscopic findings and demographic and anthropometric data were analyzed. We identified a total of 97 obese patients who underwent LSG at our hospital by studied surgeon. Sixty-three patients (64.9% of original sample) were finally evaluated in the present study, 40 (59.7%) of whom were female. The mean (range) age of patients was 38.2 (18–66) years, and mean BMI was 36.3 ± 4.1 kg/m2. Median time to follow-up EGD was 13 months (range, 12–15). Following LSG, there was a significant decrease in both BMI (42.1 ± 1.2 vs. 29.9 ± 1.0 kg/m2) and percentage excess weight loss of 56.6 ± 3.6%. The prevalence of EE on endoscopy increased from 9 (14.3%) to 28 (44.4%) patients. Of which 15 (23.8%) were grade A, 11 (17.5%) were grade B, and 2 (3.2%) were grade C. There was no correlation between GERD symptoms with EE; however, our study found a trend suggesting higher prevalence of EE with a sleeve diameter measuring > 2 cm wide (p = 0.069). Although LSG is effective in treating obesity and its metabolic syndromes, the prevalence of EE increased significantly 1 year after the surgery. Since we do not fully understand the long-term impact of chronic esophagitis in post-sleeve population, we recommend follow-up EGD assessment post-operatively and treat the esophagitis if present.

Study Design Descriptive Epidemiological Study. Introduction Ligament tears between carpal bones are easily missed on initial presentation, but can have potentially debilitating effects on the patient if they progress to an instability. They are usually the result of a fall onto an outstretched hand with the wrist in hyperextension. Current incidence of carpal instability after these falls is unknown. Purpose of the Study Using established clinical and radiological measures, we sought to establish the cumulative incidence of carpal instability in people who have fallen onto an outstretched hand in the second year after injury. We also sought to describe its relationship with functional impairment. Methods We used emergency department records of an inner-urban tertiary hospital to contact all patients who presented with wrist pain following fall onto outstretched hand who were between one and two years after injury. Carpal instability was defined by blinded radiological evaluations and provocative clinical tests, including Scaphoid Shift (Watson’s) test, Ballottement, and mid-carpal shift test. Wrist-related pain and disability was measured using the Patient-Rated Wrist and Hand Evaluation. Results Of the 279 potentially eligible cases, only 146 were contactable, and fifty (28 male, 22 female; mean age of 48 years) attended for assessment. We found a cumulative incidence of 44% of carpal instability within the second year after injury. Of these, 12 (24%) cases had scapho-lunate instability, 12 (24%) had luno-triquetral instability and 7 (14%) had mid-carpal instability. There were no significant correlations between clinically confirmed carpal instability and pain, function, or work participation. Discussion and Conclusion This study found a higher than anticipated cumulative incidence of carpal instability in the second year after injury, which may reflect volunteer bias. Patients should be advised to monitor symptoms in the year after injury and seek a review if symptoms of pain, clicking or clunking arise. Level of Evidence II

The precise deployment of functional payloads to plant tissues is a new approach to help advance the fundamental understanding of plant biology and accelerate plant engineering. Here, the design of a silk‐based biomaterial is reported to fabricate a microneedle‐like device, dubbed “phytoinjector,” capable of delivering a variety of payloads ranging from small molecules to large proteins into specific loci of various plant tissues. It is shown that phytoinjector can be used to deliver payloads into plant vasculature to study material transport in xylem and phloem and to perform complex biochemical reactions in situ. In another application, it is demonstrated Agrobacterium‐mediated gene transfer to shoot apical meristem (SAM) and leaves at various stages of growth. Tuning of the material composition enables the fabrication of another device, dubbed “phytosampler,” which is used to precisely sample plant sap. The design of plant‐specific biomaterials to fabricate devices for drug delivery in planta opens new avenues to enhance plant resistance to biotic and abiotic stresses, provides new tools for diagnostics, and enables new opportunities in plant engineering., A silk‐based biomaterial is designed to fabricate a microneedle‐like device with controlled degradation rate in planta via tuning material composition. The device enables precise access to xylem, phloem, and other plant tissues, thus being capable of serving as a delivery tool to release cargo molecules and as a sampling tool for analysis of plants fluid.

We report an artificial intelligence (AI) based method to predict the molecular structure of proteins, focused here on an important subclass of proteins dominated by alpha-helix secondary structure, as found in many structural biomaterials such as keratin and membrane proteins. Fast yet accurate predictions of an unknown protein’s 3D all-atom structure can yield a pre-screened set of candidate proteins to be investigated further via large-scale protein expression in bacteria or yeast. However, classical molecular simulations are greatly limited by the time scale and significant computational cost needed for the complete folding of a long peptide into a complex structure from scratch, which can easily exceed the capability of a supercomputer. To accelerate simulations at low computational cost here we report an innovative machine learning method to offer a high-throughput prediction of the protein structure, as well as the material and biological functions from purely the protein sequences. To achieve this, we designed a novel Multi-scale Neighborhood-based Neural Network (MNNN) model that is capable of learning the neighborhood structured information in the raw protein sequence trained on the database of over 120,000 protein structures. The method directly predicts the phi-psi dihedral angles of the backbone of each constituting amino acid, which is then used to construct the full all-atom 3D structure of the corresponding protein without any template or co-evolutional information. We find that our machine learning model can accurately predict all dihedral angles of any target sequence. The prediction yields a maximum average error of 2.1 A of the predicted 3D structure compared with experimental measurement. We find that the predicted folded structure from MNNN consumes less than six orders of magnitude time than classical molecular dynamics simulations, offering extremely fast folding predictions. Our results suggest that the MNNN model can be used to greatly accelerate the prediction of protein structures.

Background: Accelerated lipolysis and the accumulation of incomplete products of fatty acid metabolism may contribute to insulin resistance (IR). It remains unclear whether the improvement in IR during the early period following bariatric surgery could be related to changes in lipid metabolism. Aims and Hypothesis: In this study, we compared the rates of lipolysis, lipid-related acylcarnitines (ACs) and IR in morbidly obese individuals at baseline, 6-months after bariatric surgery and with lean controls. Methods: 10 morbidly obese individuals scheduled for sleeve gastrectomy and 14 lean controls were recruited. IR was quantified using OGTT while body composition was measured using the 2H2O technique or DXA scans. Glycerol flux represents whole-body lipolysis and was measured using 2H5-glycerol infusion. Plasma lipid-derived ACs were measured using mass spectrometry as an indicator of complete fatty acid oxidation. Obese subjects were reassessed 6-months after bariatric surgery. Results: Compared to lean controls, obese subjects had significantly higher fat mass (50.7 ± 1.9 vs. 16.8 ± 1.0 kg) and were significantly more IR. They had higher HOMA-IR (6.6 ± 1.0 vs. 1.43 ± 0.31), glucose and insulin AUC after OGTT. Glycerol flux (16098.1 ± 1136.2 vs. 7266.20± 497.66 umol/h), plasma glycerol (117.13 ± 10.96 vs, 46.79± 3.15 umol/L), C14 (0.225 ± 0.079 vs. 0.042± 0.012) and C16 (0.136 ± 0.016 vs. 096 ± 0.003 umol/L) ACs were significantly higher in the obese individuals. 8 subjects returned at 6-months and lost 19% of their total weight, 29% of fat mass and had a 68% decrease in HOMA-IR. Glycerol flux, plasma glycerol, C14 and C18 ACs however did not show any difference compared to baseline and remained significantly higher compared to the lean controls. Conclusion: IR improved 6-months following sleeve gastrecotmy despite accelerated lipolysis and accumulation of byproducts of incomplete fatty acid metabolism. Disclosure H. Tan: None. J.W. Hsu: None. J. Kovalik: None. C. Khoo: None. S. Chacko: None. S. Ganguly: None. E. Tai: Advisory Panel; Self; Amgen Inc., BASF. O. Lai: None. E. Lim: None. F. Jahoor: None.

In article number 1903551, Benedetto Marelli and co‐workers design a silk‐based biomaterial to fabricate a microneedle‐like device with controlled degradation rate in planta via tuning material composition. The device enables precise access to xylem, phloem, and other plant tissues, thus being capable of serving as a delivery tool to release cargo molecules and as a sampling tool for analysis of plants fluid. [Image: see text]

Obesity-induced insulin resistance leads to abnormalities in glucose, lipid, and amino acid metabolism. Our study examined the differences in insulin-mediated glucose, amino acid, and lipid metabolism between morbidly obese subjects with non-obese controls and the associated changes following sleeve gastrectomy (SG). Non-obese controls and individuals with morbid obesity and scheduled for SG were recruited. Metabolic assessments were performed for all subjects at baseline and at 6 months after SG for eight subjects. The hyperinsulinemic-euglycemic clamp technique together with comprehensive metabolomic profiling was used to quantify insulin-mediated glucose, amino acid, and lipid metabolism. Eleven morbidly obese non-diabetic subjects scheduled for SG and nine non-obese controls were recruited. Compared to controls, obese subjects had significantly lower glucose uptake (4.4 ± 0.6 vs. 17.3 ± 2.4 mg/kg FFM/min per μU/mL·100) and higher concentration of branched-chain amino acids (BCAAs, 332.5 ± 26.8 vs. 235.3 ± 11.0 μM), non-esterified fatty acid (52.9 ± 9.9 vs. 25.6 ± 6.7 μM), and lipid-related acylcarnitines (intermediate chain 389.8 ± 32.5 vs. 285.9 ± 20.5; long chain 301.7 ± 22.1 vs. 236.0 ± 13.3 nM) during insulin clamp. Body weight significantly reduced at 6 months after bariatric surgery (92.5 ± 6.3 vs. 115.2 ± 6.9 kg), together with improvements in insulin-mediated glucose uptake, and suppression of BCAAs, non-esterified fatty acids, and lipid-related metabolites. Morbid obesity in Asian individuals was associated with impairment in the regulatory actions of insulin on glucose, amino acid, and lipid metabolism, and these obesity-induced regulatory dysfunctions improved significantly 6 months after SG.