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Pancreatic cancer is the fourth leading cause of cancer-related death with a 10% 5-year overall survival rate (OS). Radiation therapy (RT) in addition to dose escalation improves the outcome by significantly increasing the OS at 2 and 3 years but is hindered by the toxicity of the duodenum. Our group showed that the insertion of hydrogel spacer reduces duodenal toxicity, but the complex anatomy and the demanding procedure make the benefits highly uncertain. Here, we investigated the feasibility of augmenting the workflow with intraoperative feedback to reduce the adverse effects of the uncertainties.We simulated three scenarios of the virtual spacer for four cadavers with two types of gross tumor volume (GTV) (small and large); first, the ideal injection; second, the nonideal injection that incorporates common spacer placement uncertainties; and third, the corrective injection that uses the simulation result from nonideal injection and is designed to compensate for the effect of uncertainties. We considered two common uncertainties: (1) "Narrowing" is defined as the injection of smaller spacer volume than planned. (2) "Missing part" is defined as failure to inject spacer in the ascending section of the duodenum. A total of 32 stereotactic body radiation therapy (SBRT) plans (33 Gy in 5 fractions) were designed, for four cadavers, two GTV sizes, and two types of uncertainties. The preinjection scenario for each case was compared with three scenarios of virtual spacer placement from the dosimetric and geometric points of view.We found that the overlapping PTV space with the duodenum is an informative quantity for determining the effective location of the spacer. The ideal spacer distribution reduced the duodenal V33Gy for small and large GTV to less than 0.3 and 0.1cc, from an average of 3.3cc, and 1.2cc for the preinjection scenario. However, spacer placement uncertainties reduced the efficacy of the spacer in sparing the duodenum (duodenal V33Gy: 1.3 and 0.4cc). The separation between duodenum and GTV decreased by an average of 5.3 and 4.6 mm. The corrective feedback can effectively bring back the expected benefits from the ideal location of the spacer (averaged V33Gy of 0.4 and 0.1cc).An informative feedback metric was introduced and used to mitigate the effect of spacer placement uncertainties and maximize the benefits of the EUS-guided procedure.

Background and Aim SpyGlass® cholangiopancreatoscopy system has shown early success in aiding diagnosis and management of pancreaticobiliary diseases. We aimed to assess the technical success, clinical success, diagnostic yield, therapeutic yield, and safety of the SpyGlass® system at a single institution. Methods A retrospective, single-center review of consecutive patients who underwent endoscopic retrograde cholangiopancreatography with SpyGlass® between January 2008 and August 2013 for a variety of indications. Technical success was defined as the procedure being completed as planned. Clinical success was defined as a successful outcome using diagnostic, clinical, laboratory, or imaging evidence. Results SpyGlass® cholangioscopy was carried out in 88 patients (49 females, mean age 56.9 ± 15.5 years). Indications were diagnostic in 67 and therapeutic in 21. Overall, technical success was seen in 87.5% and clinical success in 77.3%. Thirty-nine patients with indeterminate biliary stricture had technical and clinical success rates of 92.3% and 74.4%, respectively. In this subgroup, malignancy was ultimately diagnosed in 13 with 12 patients diagnosed by SpyGlass® and confirmed by surgical specimens in 12/12 cases; positive predictive value 100%). In the 23 remaining patients with indeterminate biliary strictures, one was later found to have malignancy (negative predictive value 95.8%) after 1 year of follow up. In the 13 therapeutic cases of stone removal, technical and clinical success was seen in 77.0% for both. Overall, adverse events were seen in 15.9%. Conclusions SpyGlass® demonstrated acceptable technical and clinical success rates in both diagnostic and therapeutic procedures. In particular, it allows for an accurate rate of diagnosis of indeterminate biliary strictures.

Background Premature ventricular complex (PVC) has been regarded as benign; however, when frequent, the arrhythmia can induce left ventricular (LV) systolic dysfunction. Meanwhile, the influence of PVCs on cardiac structural remodeling and functional change before occurrence of overt systolic heart failure has not been fully described. In this study, we attempted to identify early cardiac structural/functional manifestations of frequent PVCs in patients with normal LV systolic function. Methods A total of 146 patients (age: 55 ± 15 years, 48 males) with frequent PVCs observed on 24-hour Holter monitoring (>10/h) and normal LV ejection fraction (LV EF ≥ 55% on echocardiography) were enrolled. Clinical characteristics and echocardiographic parameters of the patients were compared with those of an age-/sex-matched control group (n = 292, age: 55 ± 15 years, 96 males). Results Patients with frequent PVCs had significantly larger left atrial volume index (LAVI [28 ± 9 mL/m2 vs. 24 ± 7 mL/m2]), along with larger LV end-diastolic dimension (49.4 ± 4.4 mm vs. 48.5 ± 3.9 mm), lower LV EF (63 ± 7% vs. 66 ± 6%), and lower peak systolic mitral annular velocity (7 ± 2 cm/s vs. 8 ± 2 cm/s; P < 0.05 for all), whereas other clinical characteristics were similar. In particular, in patients with frequent PVCs, LAVI showed linear correlation with PVC burden (R = 0.30, P < 0.001), and, in a multiple regression model, PVC burden independently estimated LAVI, even after controlling for age, sex, comorbidities, and systolic function (β = 0.309, P < 0.001). Conclusion Frequent PVC is associated with LA enlargement in patients with normal LV EF. Atrial anatomical remodeling may precede LV geometry change and systolic dysfunction in patients with frequent PVCs.

Objective To determine the effects of balanced deep-sea water (BDSW) on adipocyte hypertrophy and liver steatosis in high-fat diet (HFD)-induced obese C57BL/6J mice. Methods BDSW was prepared by mixing deep-sea water (DSW) mineral extracts and desalinated water. C57BL/6J mice were fed a normal diet or HFD with or without BDSW with different hardness (500, 1000, or 2000) for 20 weeks. Results BDSW suppressed body weight gain in HFD-fed mice. Histopathologic assays of the fat and liver revealed that BDSW inhibited the increase in adipocyte size and improved severe liver steatosis in HFD-fed mice. BDSW suppressed the expression of adipogenic, lipogenic, lipolytic, and pro-inflammatory cytokine genes and increased the expression of adipokines and β-oxidation genes in fat. In the liver, BDSW suppressed the expression of genes involved in lipogenesis and cholesterol synthesis, and increased the expression of genes related to β-oxidation. Furthermore, BDSW improved the impaired phosphorylation of IRS-1, LKB1, AMPK, and mTOR in fat and liver tissues of HFD-fed mice. Conclusions These results suggest that BDSW has potential as an anti-lipidemic agent, given its ability to suppress body weight gain and liver steatosis through the regulation of lipid metabolism by signal molecule activation.

A systematic investigation of the microstructure of ethylene copolymers has been carried out as a function of the comonomer type and content, employing small-angle X-ray scattering (SAXS) experiments to study the lamellar structure, and solid-state NMR to study the local conformational freedom. The SAXS results clearly show that the major consequence of incorporating commonomers (butene and octene) is the absence of lamellar thickening during the crystallization. From solid-state NMR study, applying the rotor-encoded rotational echo double resonance technique (REREDOR), it is found that the extent of the orientational order in the noncrystalline region of semicrystalline polyethylene is substantial but this order is not significantly affected by the incorporation of comonomer units. Therefore, the major cause for the significant improvements of mechanical properties observed for ethylene copolymers is not a change in the thermodynamic state of the noncrystalline region, but most likely a significant change in the intermolecular topological structure due to the blocking of disentanglement processes required by the lamellar thickening step during crystallization.