Effects of Various Pharmaceutical Excipients on the Intestinal Transport and Absorption of Sulfasalazine,a Typical Substrate of Breast Cancer Resistance Protein Transporter

Breast cancer resistance protein (BCRP) transporter is an efflux transporter that utilizes energy from adenosine triphosphate hydrolysis to push its substrates, regardless of the concentration gradient. Its presence on the apical membrane of the intestinal mucosa is a major obstacle for the intestinal absorption of its substrates. In this study, we examined the effects of various pharmaceutical excipients on the intestinal transport and absorption of sulfasalazine, a BCRP substrate. Four excipients, including 0.05% and 0.075% BL-9EX, 0.01% and 0.05% Brij 97, 0.075% Labrasol, and 0.05% and 0.1% Tween 20 decreased the secretory transport of sulfasalazine in an in vitro diffusion chamber. Further investigation in an in situ closed loop experiment in rats showed that 0.05% and 0.1% BL-9EX and 0.1% Brij 97 effectively enhanced the intestinal absorption of sulfasalazine while maintaining minimal toxicity to the intestinal mucosa. However, 0.1% Brij 97 also increased the intestinal absorption of 5(6)-carboxyfluorescein, a paracellular marker compound. These findings suggest that BL-9EX might effectively inhibit the BCRP-mediated efflux of sulfasalazine in vivo, indicating that BL-9EX could improve the intestinal absorption of sulfasalazine and other BCRP substrates.     

Double potential step chronoreflectometry approach to bi-stable potential region of the faradaic phase transition of heptyl viologen at a HOPG electrode

The phase transition of an adsorption layer of heptyl viologen (HV) at a basal plane HOPG electrode was investigated using double potential step chrono-reflectometry in the visible wavelength region. For the first order faradaic phase transition between an expanded adsorption layer of oxidized form (HV²⁺) and a two-dimensional (2D) condensed monolayer of reduced form (HV⁺), the nature of the bi-stable potential region was targeted to be explored. The merit of chrono-reflectometry capable of directly tracking the change of 2D superficial fractions of the two phases on the electrode surface was demonstrated experimentally. The double potential step measurements made it possible to gain access to the steady-state coexistence of the two phases in the bi-stable potential region. After the secondary reverse potential step to the positive direction into the bi-stable potential region was given from a transient nucleation state at the first step potential, the superficial fraction of the condensed phase monitored by reflectance was saturated. The plot of this saturated value (φ_dbl) as a function of potential (E) in the bi-stable potential region was found to be dependent on the time period spent at the transient nucleation potential. Therefore, the φ_dbl–E curve thus obtained does not necessarily represent a unique, true equilibrium relationship.     

Infarction of lesser omental fat mimicking an exophytic pancreatic tumor by sonography

We report a case of infarction of lesser omental fat in a 30-year-old woman who presented with epigastric pain. Sonography revealed a painful echogenic mass in the epigastrium that could not be separated from the adjacent hyperechoic pancreas and mimicked an exophytic pancreatic tumor. On CT, the mass was identified as an inflammatory lipomatous mass in the lesser sac, leading to the diagnosis of infarction of lesser omental fat. The patient was successfully treated conservatively.     

Superficial Surgical Site Infection in Hepatobiliary-Pancreatic Surgery: Subcuticular Suture Versus Skin Staples

Purpose

Postoperative superficial surgical site infection is a major complication in hepatobiliary-pancreatic surgery. We aimed to compare the efficacy of subcuticular sutures versus staples for skin closure in preventing superficial surgical site infection in hepatobiliary-pancreatic surgery.

Methods

Consecutive patients who underwent hepatobiliary-pancreatic surgery at our hospital from October 2006 to March 2011 and from April 2012 to March 2015 were reviewed retrospectively. Superficial surgical site infection incidence was evaluated in patients who received subcuticular sutures and those who received staples for skin closure. Propensity score matching analysis was used to adjust bias from confounding factors.

Results

A total of 691 patients were included. Patients with skin staple closures (n?=?346) were compared with patients with subcuticular suture closures (n?=?345). After a propensity score matching analysis, a significant difference in superficial surgical site infection incidence was found between the skin stapler group (11.3%) and subcuticular sutures group (2.6%). The same comparison was performed by a subgroup analysis and supported this finding in patients after hepatectomy without biliary reconstruction, pancreatoduodenectomy, or open laparotomy surgeries and in patients with body mass index <?25.

Conclusions

Subcuticular suturing after hepatobiliary-pancreatic surgery was more efficacious in reducing postoperative superficial surgical site infection incidence than staples for skin closure.

     

Skeletonization and Isolation of the Glissonean and Venous Branches in Liver Surgery With an Ultrasonic Scalpel Technology

This study describes a novel technique for skeletonization and isolation of Glissonean and venous branches during liver surgery using a harmonic scalpel (HS). Hepatic resections with HS were performed with the skeletonization and isolation technique in 50 patients (HS group). Variables evaluated were blood loss, operative time, biliary leak, and morbidity. The results were compared with 50 hepatic resections that were performed using a previously established technique: Cavitron ultrasonic surgical aspirator with electric cautery, ligatures, and hemoclips (NHS group). The HS group had shorter total operative times (285 versus 358 minutes; P = 0.01), less blood loss (389 versus 871 mL; P = 0.034), and less crystalloid infusion (2744 versus 3299 mL; P = 0.027) compared with the NHS group. Postoperative liver function and complication rates were similar when comparing the two groups. These data demonstrate that HS is a simple, easy, and effective instrument for the skeletonization and isolation of vessels during liver transection.Key words: Liver resection, Ultrasonic scalpel, Skeletonization, Cavitation effectVarious devices are available for liver transection, but the availability of comparative data for transection techniques is limited by the diversity of operative procedures. Clamp crushing (CC) and a Cavitron ultrasonic surgical aspirator are widely used for splitting the liver parenchyma,^1,2 and hemostasis is achieved by bipolar coagulation, ligatures, or hemoclips. Various coagulating devices, such as Ligasure,³ Tissuelink,⁴ and the Harmonic Scalpel (HS),^5–7 have recently been developed to aid in liver splitting. The choice of instrument is often based on individual surgeon preference. Higami et al^8,9 described a novel technique to skeletonize and harvest the internal thoracic artery with the HS, and the present study capitalizes on their experience to describe a unique method to skeletonize and isolate the Glissonean and venous branches using an HS.