Concurrent minimally invasive bariatric surgery and ventral hernia repair with mesh; Is it safe? Propensity score matching analysis using the 2015-2022 MBSAQIP database.

BACKGROUND: Obesity is a risk factor for the development of ventral hernias. Approximately eight percent of patients undergoing bariatric surgery have a concomitant ventral hernia. However, the optimal timing of hernia repair in these patients is debated. Concerns regarding mesh insertion in a potentially contaminated field are often cited by opponents of a combined approach. Our study compares 30-day outcomes of bariatric surgery with concurrent ventral hernia repair with mesh versus bariatric surgery alone. METHODS: Using the 2015-2022 MBSAQIP database, patients aged 18-65 years who underwent minimally invasive sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB) with or without concurrent ventral hernia repair with mesh (VHR-M) were identified. 30-day postoperative outcomes were compared between patients who underwent SG or RYGB with VHR-M versus SG or RYGB alone. 1:1 propensity score matching was performed using 26 preoperative characteristics to adjust confounders. RESULTS: Among 1,236,644 patients who underwent SG (n = 871,326) or RYGB (n = 365,318), 3,121 underwent SG + VHR-M and 2,321 RYGB + VHR-M. The concurrent approach had longer operative times, in SG + VHR-M (86.06 ± 42.78 vs. 73.80 ± 38.45 min, p < 0.001), and in RYGB + VHR-M (141.91 ± 58.68 vs. 128.47 ± 62.37 min, p < 0.001). The RYGB + VHR-M cohort had higher rates of reoperations (3.2% vs. 2.1%, p = 0.024). Overall, 30-day outcomes, and bariatric-specific complications such as mortality, unplanned ICU admissions, surgical site complications, cardiac, pulmonary, renal complications, anastomotic leaks, postoperative bleeding, and intestinal obstruction were similar between SG + VHR-M or RYGB + VHR-M groups versus SG or RYGB alone. CONCLUSION: Bariatric surgery performed concurrently with VHR-M is safe and feasible and does not excessively prolong operative times. However, patients undergoing RYGB with VHR-M do have a higher rate of reoperations, therefore a staged VHR is recommended. On the other hand, concurrent SG and VHR-M may benefit after an appropriate individualized risk stratification assessment.

Increased staple line leak rates following re-sleeve: analysis comparing re-sleeve versus Roux-en-Y gastric bypass conversion and primary sleeve gastrectomy.

BACKGROUND: Sleeve gastrectomy is the most common bariatric procedure and its long-term complications include inadequate weight loss, weight regain, and de novo GERD, often requiring revisional surgery. Revisions, notably re-sleeve and conversion to Roux-en-Y gastric bypass (RYGB), are frequently performed, but safety data is limited. Herein, we used the MBSAQIP database to compare 30 day outcomes of primary sleeve gastrectomy (SG) with re-sleeve (RS) and SG to RYGB conversion. METHODS: Patients who underwent primary SG, RS, and SG to RYGB conversion within the MBSAQIP data registry from January 1, 2020 to December 31, 2022 were included in this study. Using Propensity Score Matching analysis, the cohorts were matched for 23 preoperative characteristics. We then compared 30 day postoperative outcomes and bariatric-specific complications between primary SG and RS (analysis 1) and between RS and SG to RYGB conversion (analysis 2). RESULTS: A total of 302,961 were included. The matched cohorts in analysis 1 (n = 1630) and analysis 2 (n = 1633) had similar pre-operative characteristics. Propensity-matched outcomes in analysis 1 showed that patients in the RS group had significantly higher staple line leak (1.3% vs. 0.1%, p < 0.001) when compared to primary SG. Similarly, longer operative times (90.16 ± 51.90 min vs. 68.32 ± 37.54 min, p < 0.001) and higher rates of readmissions (5.5% vs. 2.1%, p < 0.001), reoperations (2.3% vs. 0.6%, p < 0.001), interventions (2.5% vs. 0.4%, p < 0.001) were found in those who underwent RS. In analysis 2, RS showed higher leak rates (1.3% vs. 0.5%, p = 0.015) when compared to conversion from SG to RYGB. CONCLUSION: The RS group has a higher risk of staple line leaks compared to primary SG and conversion from SG to RYGB. In our study, there was a 2.6-fold increase in staple line leak after re-sleeve compared to RYGB conversion and a 13-fold increase compared to primary SG.

Case report: Concurrent intussusception and bleeding marginal ulcer in a patient with gastric bypass.

INTRODUCTION: The source of abdominal pain in patients with a history of gastric bypass can be difficult to determine. Synchronous disease processes may ultimately be the cause of their symptoms. Among the etiologies for hematemesis and obstruction in this population are the diagnoses of marginal ulcer and internal hernia. Given the potential complications of bariatric surgery, it is important to maintain a broad differential diagnosis during the workup of these patients. PRESENTATION: A female with history of laparoscopic Roux-en-Y gastric bypass (RYGB) presented with abdominal pain and hematemesis. Intraoperative findings revealed intussusception of the jejunojejunostomy resulting in obstruction and ischemic bowel. Additionally, a perforated marginal ulcer of the Roux-limb was found to be present. This patient underwent esophagogastroduodenoscopy, bowel resection, jejunojejunostomy revision, and Graham patch repair. DISCUSSION: This case highlights a patient with history of RYGB presenting with obstruction and gastrointestinal bleeding. Although initially diagnosed with internal hernia and Mallory-Weiss hematemesis, surgical exploration revealed concurrent intussusception and marginal ulceration. While intussusception is a rare complication of bariatric surgery, it can occur secondary to mesenteric thinning and motility dysfunction from significant weight loss. It is imperative to maintain a broad differential diagnosis for the causes of obstruction and GI bleeding that include adhesive disease, abdominal wall hernia, internal hernia, intussusception, and marginal ulcers. CONCLUSION: Findings of obstruction or GI bleeding after bariatric surgery may represent a surgical emergency. While these symptoms may be attributed to a single diagnosis, clinicians must consider the presence of synchronous pathologies during the workup of patients.

Outcomes of Sleeve Gastrectomy in Patients With Organ Transplant-Related Immunosuppression.

INTRODUCTION: Obesity is frequent among organ transplant recipients, increasing the risk of acute graft rejection and overall morbimortality. Laparoscopic sleeve gastrectomy (LSG) effectively improves graft survival and associated comorbidities. We first compared 30-d outcomes between chronic immunosuppressed (CI) and nonchronic immunosuppressed (non-CI) patients. Then, between organ transplant and non-organ transplant CI patients who underwent LSG. METHODS: Patients who underwent LSG within the metabolic and bariatric surgery accreditation and quality improvement program 2017-2019 were included. Using 1:1 and 1:4 propensity score matching analysis, the cohorts were matched for 30 characteristics. We then compared 30-d outcomes between CI and non-CI (analysis 1) and between organ transplant and non-organ transplant CI patients who underwent LSG (analysis 2). RESULTS: A total of 486,576 patients were included. The matched cohorts in analysis 1 (n = 8978) and analysis 2 (n = 1152, n = 371) had similar preoperative characteristics. Propensity score matching in analysis 1 showed that patients in the CI group had significantly higher rates of renal complications (0.4% versus 0.2%, P = 0.006), unplanned intensive care unit admission (1.1% versus 0.7%, P = 0.003), blood transfusions (1.1% versus 0.7%, P = 0.003), readmissions (4.6% versus 3.5%, P < 0.001), reoperations (1.4% versus 1.0%, P = 0.033), interventions (1.3% versus 1.0%, P = 0.026), and postoperative bleeding (0.6% versus 0.4%, P = 0.013). In analysis 2, patients with organ transplant CI had a higher rate of pulmonary complications (1.1% versus 0.3%, P = 0.043), renal complications (2.4% versus 0.2%, P < 0.001), blood transfusions (6.5% versus 1.3%, P < 0.001), and readmissions (10.0% versus 4.6%, P < 0.001). CONCLUSIONS: Patients with transplant-related CI who underwent LSG have higher 30-d postoperative complication rates compared to nontransplant-related CI patients; however, there were no differences in terms of mortality, intensive care unit admissions, staple line leaks, or bleeding. LSG is safe and feasible in this high-risk population.

A superior approach? The role of robotic sleeve gastrectomy in patients with super super obesity using the 2019-2022 MBSAQIP database.

BACKGROUND: Laparoscopic sleeve gastrectomy (LSG) in patients with BMI ≥ 60 presents technical challenges, that might be overcome by robotic surgery, but its effectiveness has not been rigorously evaluated. We compared the 30-day outcomes of LSG and robotic sleeve gastrectomy (RSG) in patients with BMI < 60 versus ≥ 60 and between LSG and RSG in patients with BMI ≥ 60. METHODS: Patients aged 18-65 years who underwent sleeve gastrectomy were included using the 2019-2022 MBSAQIP database. We performed a Propensity Score Matching analysis, with 21 preoperative characteristics. We compared 30-day postoperative outcomes for patients with BMI < 60 versus ≥ 60 using either a laparoscopic (Analysis 1) or robotic approach (Analysis 2) and compared LSG versus RSG in patients with BMI ≥ 60 (Analysis 3). RESULTS: 297,250 patients underwent LSG and 81,008 RSG. Propensity-matched¸ outcomes in analysis 1 (13,503 matched cases), showed that patients with BMI ≥ 60 had higher rates of mortality (0.1% vs. 0.0%, p = 0.014), staple line leak (0.3% vs. 0.2%, p = 0.035), postoperative bleeding (0.2% vs 0.1%, p = 0.028), readmissions (3.5% vs. 2.4%, p < 0.001), and interventions (0.7% vs. 0.5%, p = 0.028) when compared to patients with BMI < 60. In analysis 2 (4350 matched cases), patients with BMI ≥ 60 demonstrated longer operative times, length of stay, and higher rates of unplanned ICU when compared to patients with BMI < 60. In analysis 3 (4370 matched cases), patients who underwent RSG had fewer readmissions (2.9% vs. 3.7%, p = 0.037), staple line leaks (0.1% vs. 0.3%, p = 0.029), and postoperative bleeding (0.1% vs. 0.3%, p = 0.045), compared to LSG. Conversely, a longer operative time (92.74 ± 38.65 vs. 71.69 ± 37.45 min, p < 0.001) was reported. CONCLUSION: LSG patients with BMI ≥ 60 have higher rates of complications compared to patients with a BMI < 60. Moreover, some outcomes may be improved with the robotic approach in patients with BMI ≥ 60. These results underscore the importance of considering a robotic approach in this super super obese population.

Facet-Defined Dilute Metal Alloy Nanorods for Efficient Electroreduction of CO2 to n-Propanol.

Electroreduction of CO2 into liquid fuels is a compelling strategy for storing intermittent renewable energy. Here, we introduce a family of facet-defined dilute copper alloy nanocrystals as catalysts to improve the electrosynthesis of n-propanol from CO2 and H2O. We show that substituting a dilute amount of weak-CO-binding metals into the Cu(100) surface improves CO2-to-n-propanol activity and selectivity by modifying the electronic structure of catalysts to facilitate C1-C2 coupling while preserving the (100)-like 4-fold Cu ensembles which favor C1-C1 coupling. With the Au0.02Cu0.98 champion catalyst, we achieve an n-propanol Faradaic efficiency of 18.2 ± 0.3% at a low potential of -0.41 V versus the reversible hydrogen electrode and a peak production rate of 16.6 mA·cm-2. This study demonstrates that shape-controlled dilute-metal-alloy nanocrystals represent a new frontier in electrocatalyst design, and precise control of the host and minority metal distributions is crucial for elucidating structure-composition-property relationships and attaining superior catalytic performance.

The Digital Transition: Are Adults Aged 65 Years or Older Willing to Complete Online Forms and Questionnaires in Patient Portals?

INTRODUCTION: Patients are being encouraged to complete forms electronically using patient portals rather than on paper, but willingness of older adults to make this transition is uncertain. METHODS: The authors analyzed data for 4105 Kaiser Permanente Northern California 2020 Member Health Survey respondents aged 65-85 years who answered a question about willingness to complete online forms and questionnaires using a patient portal. Data weighted to the Kaiser Permanente Northern California membership were used to estimate percentages of older adults willing to complete patient portal forms and questionnaires. Chi-square tests and log-Poisson regression models that included sociodemographic, internet use, and patient portal variables were used to identify factors predictive of willingness. RESULTS: Overall, 59.6% of older adults were willing to complete patient portal forms, 17.6% were not willing, and 22.8% were not sure. Adults aged 75-85 (49.5%) vs 65-74 years (64.8%) and Black (51.9%) and Latino (46.5%) vs White (62.8%) adults were less likely to indicate willingness. In addition to racial and ethnic differences and younger age, higher educational attainment, use of the internet alone (vs internet use with help or not at all), having an internet-enabled computer or tablet, and having sent at least 1 message through the patient portal increased likelihood of being willing. CONCLUSIONS: Health care teams should assess older adults' capabilities and comfort related to completion of patient portal-based forms and support those willing to make the digital transition. Paper forms and oral collection of information should remain available for those unable or unwilling to make this digital transition.

Diastereoselective Hydrogenation of Tetrasubstituted Olefins using a Heterogeneous Pt-Ni Alloy Catalyst.

Stereoselective hydrogenation of tetrasubstituted olefins is an attractive method to access compounds with two contiguous stereocenters. However, homogeneous catalysts for enantio- and diastereoselective hydrogenation exhibit low reactivity toward tetrasubstituted olefins due to steric crowding between the ligand scaffold and the substrate. Monometallic heterogeneous catalysts, on the other hand, provide accessible surface active sites for hindered olefins but exhibit unpredictable and inconsistent stereoinduction. In this work, we develop a Pt-Ni bimetallic alloy catalyst that can diastereoselectively hydrogenate unactivated, sterically-bulky tetrasubstituted olefins, utilizing the more oxophilic Ni atoms to adsorb a hydroxyl directing group and direct facially-selective hydrogen addition to the olefin via the Pt atoms. Structure-activity studies on several Pt-Ni compositions underscore the importance of exposing a uniform PtNi alloy surface to achieve high diastereoselectivity and minimize side reactions. The optimized Pt-Ni/SiO2 catalyst exhibits good functional group tolerance and broad scope for tetrasubstituted olefins in a cyclopentene scaffold, generating cyclopentanol products with three contiguous stereocenters. The synthetic utility of the method is demonstrated in a four-step synthesis of (1R,2S)-(+)-cis-methyldihydrojasmonate with high yield and enantiopurity.

Fitting in a workgroup in unique ways: A latent profile analysis of perceived person-group fit characteristics.

Research has identified seven characteristics-value congruence, shared interests, perceived demographic similarity, needs-supplies match, goal similarity, common workstyle, and complementary attributes-on which group members simultaneously evaluate their perceived person-group (PG) fit. Most of extant research has focused on how each characteristic or them as a composite predicts outcomes. However, these variable-centered approaches fail to address how there may be subpopulations of members who differentially combine the PG fit characteristics and how such conjunctive effects differentially relate to various work outcomes. To address these issues, we adopt a profile-based approach using latent profile analysis to understand how group members are similar to and different from each other on more holistic configurations of perceived PG fit experiences. With two widely different samples of employees working in group settings, we found seven unique profiles of PG fit: perfect fits, comfortable fits, surface-level misfits, out of syncs, social misfits, lone wolves, and total misfits. We also found in Sample 2 that these profiles differentially predicted group member outcomes commonly studied in the PG fit literature, including attitudes (satisfaction and cohesion), performance behaviors (task performance and citizenship behaviors of helping and voice), and withdrawal (social loafing and turnover). Complementing research that used variable-centered approaches, our profile-based results reveal new theoretical and practical insights of perceived PG fit, suggesting that different group members have distinct configurations of PG fit, and that higher levels of PG fit are not universally positive, and neither is every type of misfit universally negative. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Vitamin D Status among Women of Different Asian Subgroups Initiating Osteoporosis Therapy.

Among 1866 Asian women (901 Filipina women, 654 Chinese women, and 311 Japanese women) who had vitamin D assessment prior to initiation of osteoporosis therapy, Filipina women had a lower prevalence of vitamin D deficiency compared to Chinese women, despite higher body mass index. In multivariable analyses that adjusted for age, body mass index, and smoking status, the relative risk of low vitamin D was significantly higher for Chinese women (relative risk 1.4, 95% confidence interval 1.1-1.7) but not Japanese women (relative risk 1.2, 95% confidence interval 0.9-1.6). The 40% higher risk of low Vitamin D in Chinese compared to Filipina women emphasizes the importance of disaggregating Asian race when examining nutritional health attributes.

Reaction Chemistry at Discrete Organometallic Fragments on Black Phosphorus.

Black phosphorus (bP) is a two-dimensional van der Waals material unique in its potential to serve as a support for single-site catalysts due to its similarity to molecular phosphines, ligands quintessential in homogeneous catalysis. However, there is a scarcity of synthetic methods to install single metal centers on the bP lattice. Here, we demonstrate the functionalization of bP nanosheets with molecular Re and Mo complexes. A suite of characterization techniques, including infrared, X-ray photoelectron and X-ray absorption spectroscopy as well as scanning transmission electron microscopy corroborate that the functionalized nanosheets contain a high density of discrete metal centers directly bound to the bP surface. Moreover, the supported metal centers are chemically accessible and can undergo ligand exchange transformations without detaching from the surface. The steric and electronic properties of bP as a ligand are estimated with respect to molecular phosphines. Sterically, bP resembles tri(tolyl)phosphine when monodentate to a metal center, and bis(diphenylphosphino)propane when bidentate, whereas electronically bP is a σ-donor as strong as a trialkyl phosphine. This work is foundational in elucidating the nature of black phosphorus as a ligand and underscores the viability of using bP as a basis for single-site catalysts.

Laparoscopic sleeve gastrectomy to Roux-en-Y gastric bypass conversion versus primary Roux-en-Y gastric bypass: a propensity score matching analysis.

BACKGROUND: Secondary bariatric surgery rates have increased, accounting for approximately 19% of the total bariatric cases in the last years, most commonly conversion of sleeve gastrectomy to gastric bypass. Using the MBSAQIP, we evaluate the outcomes of this procedure compared to the primary RYGB surgery. METHODS: The new variable, conversion of sleeve gastrectomy to RYGB in the 2020 and 2021 MBSAQIP database was analyzed. Patients who underwent primary laparoscopic RYGB and those who underwent laparoscopic sleeve gastrectomy to RYGB conversion were identified. Using Propensity Score Matching analysis, the cohorts were matched for 21 preoperative characteristics. We then compared 30-day outcomes and bariatric-specific complications between primary RYGB and conversion from sleeve gastrectomy to RYGB. RESULTS: There were 43,253 primary RYGB procedures performed and 6,833 conversions from sleeve gastrectomy to RYGB. The matched cohorts (n = 5912) for the two groups have similar pre-operative characteristics. Propensity-matched outcomes showed that conversion from sleeve gastrectomy to RYGB was associated with more readmissions (6.9% vs 5.0%, p < 0.001), interventions (2.6% vs 1.7%, p < 0.001), conversion to open (0.7% vs 0.2%, p < 0.001), length of stay (1.79 ± 1.77 days vs 1.62 ± 1.66 days, p < 0.001), and operative time (119.16 ± 56.82 min vs 138.27 ± 66.00, p < 0.001). There were no significant differences in mortality (0.1% vs 0.1%, p = 0.405), and bariatric-specific complications such as anastomotic leak (0.5% vs 0.4%, p = 0.585), intestinal obstruction (0.1% vs 0.2%, p = 0.808), internal hernia (0.2% vs 0.1%, p = 0.285) or anastomotic ulcer (0.3% vs 0.3%, p = 0.731) rates. CONCLUSION: Conversion from sleeve gastrectomy to RYGB is a safe and feasible operation with reasonable outcomes compared with primary RYGB.

Comparative outcomes of bariatric surgery in patients with ESRD on dialysis in the modern era of renal transplantation: analysis using the 2015-2020 MBSAQIP database.

BACKGROUND: Severe obesity is a relative contraindication for renal transplantation, therefore bariatric surgery is an important option as a pre-kidney transplant weight loss strategy. However, comparative data regarding postoperative outcomes of laparoscopic sleeve gastrectomy (LSG) or laparoscopic Roux-en-Y gastric bypass (LRYGB) in patients with or without ESRD on dialysis are scarce. METHODS: Patients between 18- and 80-year-old who underwent LSG and RYGB were included. To determine the outcomes of patient who underwent bariatric surgery with ESRD on dialysis, a 1:4 PSM was performed between the patients with ESRD on dialysis and those without renal disease. The PSM analyses in both groups were performed using 20 preoperative characteristics. Then 30-day postoperative outcomes were assessed. RESULTS: The operative time and postoperative-LOS were significantly longer in ESRD patients on dialysis compared to those with no renal disease either for LSG (82.37 ± 40.42 vs. 73.62 ± 38.65; P < 0.001, 2.22 ± 3.01 vs. 1.67 ± 1.90; P < 0.001) or for LRYGB (129.13 ± 63.20 vs. 118.72 ± 54.16; P = 0.002, 2.53 ± 1.74 vs. 2.00 ± 1.68; P < 0.001). In the LSG cohort (2137 vs. 8495 matched cases), patients with ESRD on dialysis showed significant increase in mortality (0.7% vs 0.3%; P = 0.019), unplanned ICU admission (3.1% vs 1.3%; P < 0.001), blood transfusions (2.3% vs 0.8%; P 0.001), readmissions (9.1% vs. 4.0%; P < 0.001), reoperations (3.4% vs. 1.2%; P < 0.001), interventions (2.3% vs. 1.0%; P = 0.006). In the LRYGB group (443 vs. 1769 matched cases), patients with ESRD on dialysis showed a significantly higher need for unplanned ICU admission (3.8% vs. 1.4%; P = 0.027), readmissions (12.4% vs. 6.6%; P = 0.011), and interventions (5.2% vs. 2.0%; P = 0.050). CONCLUSION: Bariatric surgery is a safe procedure for patients with ESRD on dialysis to help them get a kidney transplant. Even though this group experienced a higher incidence of postoperative complications compared to those without kidney disease, the absolute complication rates are low and not associated with bariatric-specific complications. Therefore, ESRD should not be perceived as contraindications to bariatric surgery.

Do advances in technology translate to improved outcomes? Comparing robotic bariatric surgery outcomes over two-time intervals utilizing the MBSAQIP database.

BACKGROUND: This study aims to compare outcomes and utilization of robotics in bariatric procedures across two-time intervals, chosen because they correspond to drastic changes in technology utilization-namely, a new platform and a new stapling device. Outcomes of robotic Roux-en-Y gastric bypass (rRYGB) and robotic sleeve gastrectomy (rSG) across this changing landscape have not been well studied, despite increasing popularity. METHODS: The MBSAQIP database was analyzed over early (2015-2016) and late (2019-2020) time intervals. Patients who underwent rSG and rRYGB were identified, and the cohorts were matched for 26 preoperative characteristics using Propensity Score Matching Analysis. We then compared 30-day outcomes and bariatric-specific complications between the early and late time frames for rSG and rRYGB. RESULTS: 49,442 rSG were identified: 13,526 cases in the early time frame and 35,916 in the late time frame. The matched cohorts were 13,526 for the two groups. 30-day outcomes showed that in the late time frame, rSG was associated with lower rates of pulmonary complications (0.1% vs 0.3%, p < 0.001), readmissions (2.5% vs 3.6%, p < 0.001), interventions (0.6% vs 1.4%, p < 0.001), reoperations (0.7% vs 1.0%, p = 0.024), length of stay (1.36 ± 1.01 days vs 1.76 ± 1.79 days, p < 0.001), operative time (92.47 ± 41.70 min vs102.76 ± 45.67 min p < 0.001), staple line leaks (0.2% vs 0.4%, p = 0.001) and strictures (0.0% vs 0.2%, p < 0.001). Similarly, 21,933 rRYGB were found: 6,514 cases were identified in the early time frame and 15,419 in the late time frame. The matched cohorts were 6,513 for the two groups. 30-day outcomes revealed that the late time fame rRYGB was associated with lower rates of pulmonary complications (0.1% vs 0.3%, p = 0.012), readmissions (6.3% vs 7.2%, p = 0.050), interventions (2.0% vs 3.1%, p < 0.001), length of stay (1.69 ± 1.46 days vs 2.13 ± 2.12 days p < 0.001), postoperative bleeding (0.4% vs 0.7%, p = 0.001), stricture (0.4% vs 0.8%, p < 0.001) and anastomotic ulcer (0.2% vs 0.4%, p = 0.013). CONCLUSION: Compared to early robotic bariatric surgery outcomes, a significant reduction in pulmonary complications, readmissions, reoperations, interventions and length of stay were seen in 2019-20 after rSG and rRYGB. Potential contributing factors include increased surgical experience and advances in the robotic platform. A significant recent reduction in staple line leaks with faster operative times associated with rSG suggests that stapling technology has had a positive impact on patient outcomes.

Solution-Phase Synthesis of Vanadium Intercalated 1T'-WS2 with Tunable Electronic Properties.

Metal ion intercalation into Group VI transition metal dichalcogenides enables control over their carrier transport properties. In this work, we demonstrate a low-temperature, solution-phase synthetic method to intercalate cationic vanadium complexes into bulk WS2. Vanadium intercalation expands the interlayer spacing from 6.2 to 14.2 Å and stabilizes the 1T' phase of WS2. Kelvin-probe force microscopy measurements indicate that vanadium binding in the van der Waals gap causes an increase in the Fermi level of 1T'-WS2 by 80 meV due to hybridization of vanadium 3d orbitals with the conduction band of the TMD. As a result, the carrier type switches from p-type to n-type, and carrier mobility increases by an order of magnitude relative to the Li-intercalated precursor. Both the conductivity and thermal activation barrier for carrier transport are readily tuned by varying the concentration of VCl3 during the cation-exchange reaction.

Parameters, architecture and emergent properties of the Pseudomonas aeruginosa LasI/LasR quorum-sensing circuit.

Quorum sensing is a widespread process in bacteria that controls collective behaviours in response to cell density. Populations of cells coordinate gene expression through the perception of self-produced chemical signals. Although this process is well-characterized genetically and biochemically, quantitative information about network properties, including induction dynamics and steady-state behaviour, is scarce. Here we integrate experiments with mathematical modelling to quantitatively analyse the LasI/LasR quorum sensing pathway in the opportunistic pathogen Pseudomonas aeruginosa. We determine key kinetic parameters of the pathway and, using the parametrized model, show that quorum sensing behaves as a bistable hysteretic switch, with stable on and off states. We investigate the significance of feedback architecture and find that positive feedback on signal production is critical for induction dynamics and bistability, whereas positive feedback on receptor expression and negative feedback on signal production play a minor role. Taken together, our data-based modelling approach reveals fundamental and emergent properties of a bacterial quorum sensing circuit, and provides evidence that native quorum sensing can indeed function as the gene expression switch it is commonly perceived to be.

Adipose Tissue Insulin Resistance Predicts the Severity of Liver Fibrosis in Patients With Type 2 Diabetes and NAFLD.

CONTEXT: Although type 2 diabetes (T2D) is a risk factor for liver fibrosis in nonalcoholic fatty liver disease (NAFLD), the specific contribution of insulin resistance (IR) relative to other factors is unknown. OBJECTIVE: Assess the impact on liver fibrosis in NAFLD of adipose tissue (adipose tissue insulin resistance index [adipo-IR]) and liver (Homeostatic Model Assessment of Insulin Resistance [HOMA-IR]) IR in people with T2D and NAFLD. DESIGN: Participants were screened by elastography in the outpatient clinics for hepatic steatosis and fibrosis, including routine metabolites, cytokeratin-18 (a marker of hepatocyte apoptosis/steatohepatitis), and HOMA-IR/adipo-IR. SETTING: University ambulatory care practice. PARTICIPANTS: A total of 483 participants with T2D. INTERVENTION: Screening for steatosis and fibrosis with elastography. MAIN OUTCOME MEASURES: Liver steatosis (controlled attenuation parameter), fibrosis (liver stiffness measurement), and measurements of IR (adipo-IR, HOMA-IR) and fibrosis (cytokeratin-18). RESULTS: Clinically significant liver fibrosis (stage F ≥ 2 = liver stiffness measurement ≥8.0 kPa) was found in 11%, having more features of the metabolic syndrome, lower adiponectin, and higher aspartate aminotransferase (AST), alanine aminotransferase, liver fat, and cytokeratin-18 (P < 0.05-0.01). In multivariable analysis including just clinical variables (model 1), obesity (body mass index [BMI]) had the strongest association with fibrosis (odds ratio, 2.56; CI, 1.87-3.50; P < 0.01). When metabolic measurements and cytokeratin-18 were included (model 2), only BMI, AST, and liver fat remained significant. When fibrosis stage was adjusted for BMI, AST, and steatosis (model 3), only Adipo-IR remained strongly associated with fibrosis (OR, 1.51; CI, 1.05-2.16; P = 0.03), but not BMI, hepatic IR, or steatosis. CONCLUSIONS: These findings pinpoint to the central role of dysfunctional, insulin-resistant adipose tissue to advanced fibrosis in T2D, beyond simply BMI or steatosis. The clinical implication is that targeting adipose tissue should be the priority of treatment in NAFLD.

Sex and Sexual Identity Differences in Poly-tobacco Use and Psychological Distress in U.S. Adults: Results From the National Health Interview Survey.

INTRODUCTION: Poly-tobacco use (PTU), or the concomitant use of two or more nicotine and tobacco products, are a growing public health concern. Adults reporting increased psychological distress (PD) experience profound nicotine and tobacco health-related disparities. Sexual minority (SM) adults report more PTU and higher levels of PD than heterosexuals, yet little is known about patterns of nicotine and tobacco use and its relationship to PD in SM populations. AIMS AND METHODS: The purpose of this study was to investigate sexual identity differences in PD and PTU. Data were drawn from the 2016-2018 National Health Interview Survey (N = 83 017), an annual cross-sectional survey of a nationally representative sample of U.S. adults. PD was assessed using the Kessler Psychological Distress Scale (K6). We fit sex-stratified, weighted, adjusted logistic models to compare PTU and PD by sexual identity. RESULTS: PTU was more prevalent in adults with higher K6 scores. Female adults and SM adults had significantly higher K6 scores and were significantly more likely to experience serious PD when compared to their male and heterosexual counterparts. CONCLUSIONS: The current study provides a snapshot of trends in PTU in relation to PD, gender, and sexual identity. Findings suggest higher rates of both PD and PTU in SM adults. Further research examining the mechanisms underlying this disparity is critical to the development of effective intervention and prevention strategies. IMPLICATIONS: Little is known about sex and sexual identity differences in the relations between patterns of tobacco product use and PD. This study is the first to examine the effect of gender and sexual identity on both PD and PTU. SMs reported higher rates of PD and were more likely to be poly-tobacco users. As new ways of engaging nicotine/tobacco continue to proliferate, health risks will endure especially for marginalized populations. An increased understanding of the psychological and social correlates of PTU in SMs is warranted.