Short term safety of magnetic sphincter augmentation vs minimally invasive fundoplication: an ACS-NSQIP analysis.

PURPOSE: Magnetic Sphincter Augmentation (MSA) is an FDA-approved anti-reflux procedure with comparable outcomes to fundoplication. However, most data regarding its use are limited to single or small multicenter studies which may limit the generalizability of its efficacy. The purpose of this study is to evaluate the outcomes of patients undergoing MSA vs fundoplication in a national database. MATERIALS AND METHODS: The 2017-2020 American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) Registry was utilized to evaluate patients undergoing MSA or fundoplication. Patients requiring Collis gastroplasty, paraesophageal hernia repair, and emergency cases, were excluded. Patient outcomes included overall complication rates, readmissions, reoperations, and mortality. RESULTS: A total of 7,882 patients underwent MSA (n = 597) or fundoplication (n = 7285). MSA patients were younger (51 vs 57, p < 0.001), and more often male (49.6 vs 34.3%, p < 0.001). While patients undergoing MSA experienced similar rates of reoperation (1.0 vs 2.0%, p = 0.095), they experienced fewer readmissions (2.2 vs 4.7%, p = 0.005), complications (0.6 vs 4.0%, p < 0.001), shorter mean (SD) hospital length of stay(days) (0.4 ± 4.3 vs 1.8 ± 4.6, p < 0.001) and operative time(min) (80.8 ± 36.1 vs 118.7 ± 63.7, p < 0.001). Mortality was similar between groups (0 vs 0.3%, p = 0.175). On multivariable analysis, MSA was independently associated with reduced postoperative complications (OR 0.23, CI 0.08 to 0.61, p = 0.002), readmissions (OR 0.53, CI 0.30 to 0.94, p = 0.02), operative time (RC - 36.56, CI - 41.62 to - 31.49. p < 0.001) and length of stay (RC - 1.22, CI - 1.61 to - 0.84 p < 0.001). CONCLUSION: In this national database study, compared to fundoplication MSA was associated with reduced postoperative complications, fewer readmissions, and shorter operative time and hospital length of stay. While randomized trials are lacking between MSA and fundoplication, both institutional and national database studies continue to support the use of MSA as a safe anti-reflux operation.

Use of magnetic sphincter augmentation as an adjunct procedure in paraesophageal hernia repair.

Magnetic sphincter augmentation (MSA) is an anti-reflux procedure with comparable outcomes to fundoplication, yet its use in patients with larger hiatal or paraesophageal hernias has not been widely reported. This review discusses the history of MSA and how its utilization has evolved from initial Food and Drug Administration (FDA) approval in 2012 for patients with small hernias to its contemporary use in patients with paraesophageal hernias and beyond.

Insulin and IGF-I stimulate the formation of the eukaryotic initiation factor 4F complex and protein synthesis in C2C12 myotubes independent of availability of external amino acids.

The objective of this study was to investigate the effect of insulin and IGF-I on protein synthesis and translation initiation in C2C12 myotubes in nutrient-deprived Dulbecco's phosphate buffered saline (DPBS). The results showed that insulin and IGF-I increased protein synthesis by 62% and 35% respectively in DPBS, and the effect was not affected by rapamycin, but was blocked by LY294002. Insulin and IGF-I stimulated eukaryotic initiation factor 4E (eIF4E) binding protein (4EBP1) phosphorylation in a dose-dependent manner, and the stimulation was independent of availability of external amino acids. Both LY294002 and rapamycin blocked the insulin and IGF-I-induced increases in 4EBP1 phosphorylation. The results also showed that insulin and IGF-I were able to stimulate PKB/Akt phosphorylation, glycogen synthase kinase (GSK) 3beta phosphorylation and mTOR phosphorylation in DPBS. Insulin and IGF-I increased the amount of eIF4G associated with eIF4E in nutrient-deprived C2C12 myotubes. The amount of 4EBP1 associated with eIF4E was decreased after insulin or IGF-I stimulation. We conclude that in C2C12 myotubes, insulin and IGF-I may regulate protein synthesis and translation initiation independent of external amino acid supply via the phosphatidylinositol-3 kinase-PKB/Akt-mTOR pathway.

Anabolic effects of insulin and IGF-I in the ovine fetus are reduced by prolonged maternal fasting.

Fetal nutritional stress may result in intrauterine growth restriction and postnatal insulin resistance. To determine whether insulin resistance can begin in utero, we subjected late-gestation (130-135 days) ewes to 120 h of complete fasting and compared the results with our previous work in fed ewes (38). We determined the effect of insulin and/or recombinant human (rh)IGF-I infusion on ovine fetal phenylalanine kinetics, protein synthesis, and phenylalanine accretion. Experimental infusates were 1) saline, 2) rhIGF-I plus a replacement dose of insulin (40 nmol IGF-I/h + 16 mIU insulin/h), 3) insulin (890 mIU/h), and 4) IGF-I plus insulin (40 nmol IGF-I/h + 890 mIU insulin/h). During hormone infusion, both glucose and amino acid concentrations were clamped at basal concentrations. Amino acid infusion was required during infusion of either hormone to maintain plasma concentrations constant. However, the amount required during insulin infusion was less than during IGF-I infusion and 40% less than the amount required during identical studies in nonfasted animals. Phenylalanine used for protein synthesis and accretion was increased compared with control animals but again less so than in the nonfasted animals. In contrast to nonfasted animals, neither hormone increased the fractional synthetic rate of skeletal muscle protein nor that of plasma albumin. These results indicate that a short but severe nutritional stress can significantly alter the fetal anabolic response to insulin even when both glucose and amino acid substrate supplies are restored. Therefore, adaptive responses characterized by insulin resistance begin in utero when the fetus is subjected to sufficient nutritional stress.

Protein anabolic effects of insulin and IGF-I in the ovine fetus.

We determined the effect of insulin and/or recombinant human (rh)IGF-I infusion on ovine fetal phenylalanine kinetics, protein synthesis, and phenylalanine accretion. The chronically catheterized fetal lamb model was used at 130 days gestation. All studies were performed while fetal glucose and amino acid concentrations were held constant. Experimental infusates were 1). saline, 2). rhIGF-I plus a replacement dose of insulin (40 nmol), 3). insulin (890 mIU/h), and 4). IGF-I plus insulin (40 nmol IGF-I/h and 890 mIU insulin/h). Both hormones increased glucose and amino acid utilization, with insulin having a greater effect. The major effect on phenylalanine kinetics was a pronounced fall in phenylalanine hydroxylation, again with insulin having the greatest effect. Whole body protein breakdown was not significantly altered by either hormone; whole body protein synthesis was significantly increased during the combined infusion. Protein accretion was increased by both hormones, with the greatest increase during combined infusion. The fractional synthetic rate (FSR) of circulating albumin was increased by IGF-I but not by insulin. Both hormones significantly increased skeletal muscle FSR without a synergistic effect. The anabolic effects of insulin and IGF-I were more pronounced in these studies than in previous studies where amino acid concentrations were not maintained. The present data also suggest that insulin and IGF-I promote fetal growth through distinct, organ-specific mechanisms.

Fibronectin facilitates Mycobacterium tuberculosis attachment to murine alveolar macrophages.

Mycobacterium tuberculosis remains a major cause of pulmonary infection worldwide. Attachment of M. tuberculosis organisms to alveolar macrophages (AMs) represents the earliest phase of primary infection in pulmonary tuberculosis. In this study fibronectin (Fn), an adhesive protein, is shown to bind M. tuberculosis organisms and facilitates attachment of M. tuberculosis to murine AMs. A monoclonal antibody (MAb) specific to the heparin binding domain (HBD) of Fn decreases (125)I-Fn binding to M. tuberculosis; whereas MAbs specific to either the cell binding domain (CBD) or the gelatin binding domain (GBD) have no effect on Fn binding to M. tuberculosis. In the presence of exogenous Fn (10 microg/ml) M. tuberculosis attachment to AMs increased significantly from control levels (means +/- standard errors of the means) of 11.5% +/- 1.1% to 44.2% +/- 4.2% (P < 0.05). Fn-enhanced attachment was significantly decreased from 44.2% +/- 4.2% to 10.8% +/- 1.2% (P < 0.05) in the presence of anti-Fn polyclonal antibodies. The attachment is also inhibited in the presence of MAbs specific for the HBD and CBD, whereas MAbs specific to GBD did not affect the attachment. Further, an Fn cell binding peptide, Arg-Gly-Asp-Ser (RGDS), decreased the attachment from 44.2% +/- 4.2% to 15.3% +/- 1.2% (P < 0.05), whereas addition of a control peptide, Arg-Gly-Glu-Ser (RGES) did not affect the attachment (40.5% +/- 1.8%). These results suggest that Fn-mediated attachment of M. tuberculosis can occur through the binding of Fn to the AM via the CBD and to M. tuberculosis organisms via the HBD.