Evaluation of Adaptive Changes by Non-Invasive Imaging in Hepatic Vein Outflow Obstruction

Hepatic vein outflow obstruction induces remarkable changes of intra–hepatic blood circulation; the significance of these changes remains uncertain. Six patients with obstruction of the hepatic veins were evaluated by duplex Doppler ultrasound and computed tomography. The adaptive changes secondary to obstruction were analyzed and their significance was correlated with the clinical findings. Four patients presenting unilateral hepatic vein occlusion had unilateral reversed portal flow. Two of them, with lobar liver atrophy and contralateral compensatory hypertrophy required operation; the other two, with normal appearance of the liver, benefitted from conservative treatment. Two patients with bilateral hepatic vein occlusion, intra-hepatic bypasses, bilateral lobar atrophy and caudate lobe hypertrophy, received operations. Intrahepatic unilateral portal flow reversal compensates for unilateral hepatic outflow obstruction. The combination of complete or subtotal hepatic vein obstruction and atrophy–hypertrophy complex predicates advanced disease despite flow reversal or spontaneous shunt

Особенности электрохимического осаждения тугоплавких сплавов на алмазах

The analysis of theoretical foundations of electrochemical separation of refractory elements (tungsten and molybdenum) from aqueous solutions of electrolytes and practical production of refractory alloys (nickel-tungsten and nickel-molybdenum) for diamond grit’s metal coatings is shown. The influence of current load on the metallization degree and alloy output current is established. The structure of the surface coatings, their composition and effect of composition on the dynamic strength of coated diamond powders are defined. The areas for further work on granulation of high-strength metal-coated diamond grits and the creation of heterogeneous wear-resistant metal-diamond structures are identified

Toward homochiral protocells in noncatalytic peptide systems

The activation-polymerization-epimerization-depolymerization (APED) model of Plasson et al. has recently been proposed as a mechanism for the evolution of homochirality on prebiotic Earth. The dynamics of the APED model in two-dimensional spatially-extended systems is investigated for various realistic reaction parameters. It is found that the APED system allows for the formation of isolated homochiral proto-domains surrounded by a racemate. A diffusive slowdown of the APED network such as induced through tidal motion or evaporating pools and lagoons leads to the stabilization of homochiral bounded structures as expected in the first self-assembled protocells.Comment: 10 pages, 5 figure

Comparative Analysis of Opioid Use Between Robotic and Open Pancreatoduodenectomy

BACKGROUND/PURPOSE: Risk-stratified pancreatectomy clinical pathways using regional anesthesia and multimodality analgesia have decreased overall opioid use, but the additional benefits of robotic surgery in opioid reduction for pancreatoduodenectomy (PD) are unknown. We compared the inpatient opioid use between robotic PD and open PD. METHODS: Patients undergoing open PD within a protocol evaluating preincisional regional anesthetic block bundles were compared to consecutively-treated patients undergoing robotic PD identified from a prospectively maintained single-institutional database. Clinical characteristics, operative outcomes, pain scores and inpatient oral morphine equivalent (OME) use were compared between patients treated with robotic or open PD. Patients with a history of continuous-release opioid dependence were excluded. RESULTS: Of 114 total patients, 25 underwent robotic PD and 89 underwent open PD. Intraoperative opioid use was not different (P = .87), nor were cumulative pain scores. Robotic PD patients used significantly fewer OMEs per day on postoperative days 1-4 (P = .039), used fewer total OMEs during hospitalization (robotic: median = 79, IQR 42.5-141; open: median = 126, IQR 61.3-203.8; P = .0036) and were discharged with fewer OMEs (robotic: median = 0, IQR 0-43.8; open: median = 25, IQR 0-75; P = .009) despite a shorter length of stay (robotic: median = 4, open: median = 5, P = .002). CONCLUSIONS: Robotic PD patients required fewer inpatient OMEs than open PD while maintaining similar pain scores. A higher percentage of robotic PD patients tapered off of opioids prior to discharge than open surgery patients treated with a standardized opioid reduction protocol despite a shorter length of stay. These results provide a rationale for choosing robotic PD when feasible to minimize opioid use

Assessment of Future Remnant Liver Function Using Hepatobiliary Scintigraphy in Patients Undergoing Major Liver Resection

Tc-99m-mebrofenin hepatobiliary scintigraphy (HBS) was used as a quantitative method to evaluate liver function. The aim of this study was to compare future remnant liver function assessed by Tc-99m-mebrofenin hepatobiliary scintigraphy with future remnant liver volume in the prediction of liver failure after major liver resection. Computed tomography (CT) volumetry and Tc-99m-mebrofenin hepatobiliary scintigraphy were performed prior to major resection in 55 high-risk patients, including 30 patients with parenchymal liver disease. Liver volume was expressed as percentage of total liver volume or as standardized future remnant liver volume. Receiver operating characteristic (ROC) curve analysis was performed to identify a cutoff value for future remnant liver function in predicting postoperative liver failure. Postoperative liver failure occurred in nine patients. A liver function cutoff value of 2.69%/min/m(2) was calculated by ROC curve analysis. Tc-99m-mebrofenin hepatobiliary scintigraphy demonstrated better sensitivity, specificity, and positive and negative predictive value compared to future remnant liver volume. Using Tc-99m-mebrofenin hepatobiliary scintigraphy, one cutoff value suffices in both compromised and noncompromised patients. Preoperative Tc-99m-mebrofenin hepatobiliary scintigraphy is a valuable technique to estimate the risk of postoperative liver failure. Especially in patients with uncertain quality of the liver parenchyma, Tc-99m-mebrofenin HBS proved of more value than CT volumetr

Neoadjuvant FOLFIRI+bevacizumab in patients with resectable liver metastases from colorectal cancer: a phase 2 trial.

BACKGROUND: Preoperative treatment of resectable liver metastases from colorectal cancer (CRC) is a matter of debate. The aim of this study was to assess the feasibility and activity of bevacizumab plus FOLFIRI in this setting. METHODS: Patients aged 18-75 years, PS 0-1, with resectable liver-confined metastases from CRC were eligible. They received bevacizumab 5 mg kg(-1) followed by irinotecan 180 mg m(-)(2), leucovorin 200 mg m(-)(2), 5-fluorouracil 400 mg m(-)(2) bolus and 5-fluorouracil 2400 mg m(-)(2) 46-h infusion, biweekly, for 7 cycles. Bevacizumab was stopped at cycle 6. A single-stage, single-arm phase 2 study design was applied with 1-year progression-free rate as the primary end point, and 39 patients required. RESULTS: From October 2007 to December 2009, 39 patients were enrolled in a single institution. Objective response rate was 66.7% (95% exact CI: 49.8-80.9). Of these, 37 patients (94.9%) underwent surgery, with a R0 rate of 84.6%. Five patients had a pathological complete remission (14%). Out of 37 patients, 16 (43.2%) had at least one surgical complication (most frequently biloma). At 1 year of follow-up, 24 patients were alive and free from disease progression (61.6%, 95% CI: 44.6-76.6). Median PFS and OS were 14 (95% CI: 11-24) and 38 (95% CI: 28-NA) months, respectively. CONCLUSION: Preoperative treatment of patients with resectable liver metastases from CRC with bevacizumab plus FOLFIRI is feasible, but further studies are needed to define its clinical relevance

Tuning chelation by the surfactant-like peptide A6H using predetermined pH values

We examine the self-assembly of a peptide A6H comprising a hexa-alanine sequence A6 with a histidine (H) “head group”, which chelates Zn2+ cations. We study the self assembly of A6H and binding of Zn2+ ions in ZnCl2 solutions, under acidic and neutral conditions. A6H self-assembles into nanotapes held together by a β-sheet structure in acidic aqueous solutions. By dissolving A6H in acidic ZnCl2 solutions, the carbonyl oxygen atoms in A6H chelate the Zn2+ ions and allow for β-sheet formation at lower concentrations, consequently reducing the onset concentration for nanotape formation. A6H mixed with water or ZnCl2 solutions under neutral conditions produces short sheets or pseudocrystalline tapes, respectively. The imidazole ring of A6H chelates Zn2+ ions in neutral solutions. The internal structure of nanosheets and pseudocrystalline sheets in neutral solutions is similar to the internal structure of A6H nanotapes in acidic solutions. Our results show that it is possible to induce dramatic changes in the self-assembly and chelation sites of A6H by changing the pH of the solution. However, it is likely that the amphiphilic nature of A6H determines the internal structure of the self-assembled aggregates independent from changes in chelation

Insights on the mechanism of formation of protein microspheres in a biphasic system

Microspheres of bovine serum albumin (BSA) and silk fibroin are produced by applying ultrasound in a biphasic system consisting of an aqueous protein solution and an organic solvent. The protein microspheres are dispersed in an aqueous media where the protein remains at the interface covering the organic solvent. This only occurs when high shear forces are applied that induce changes to force the protein to the interface. Fourier transform infrared results indicate a large increase in the content of the β-sheet during the formation of silk fibroin microspheres. Molecular dynamics simulations show a clear adaption on the 3D structure of BSA when stabilized at the interface, without major changes in secondary structure. Further studies demonstrate that high water content, oil solvents, and larger peptides with separated and clear hydrophobic and hydrophilic areas lead to more stable and smaller spheres. This is the first time that these results are presented. We also present herein the rationale to produce tailored protein microspheres with a controlled size, controlled charge, and increased stability.This work was supported by Lidwine Project-Multifunctional medical textiles for wound (e.g., Decubitus) prevention and improved wound healing NMP2-CT-2006-026741. H.F. thanks POPH/FSE for cofinancing and FCT for Fellowship SFRH/BPD/38939/2007. We acknowledge Silvia Cappellozza from "Sezione Specializzata per la Bachicoltura" for the supply of silk cocoons