Novel Retractor-Camera System Facilitates Less Traumatic Minimally Invasive Procedures and Declutters the Operation Field.

Objective: To develop a novel endoscopic system that reduces trauma to the patient and declutters the surgical field for the surgeon in minimally invasive heart valve surgery.

Methods: We designed and developed a retractor-camera combination for minimally invasive heart surgery; the cable and camera were connected to the underbelly of the left atrial retractor blade to provide an illuminated, wide-angle view of the mitral valve. We conducted ex vivo, in vivo, and, ultimately, a first-in-man randomized, nonanonymized clinical trial on 20 patients who required minimally invasive mitral valve surgery.

Amorphous ITZO-Based Selector Device for Memristor Crossbar Array.

In the era of digital transformation, a memristor and memristive circuit can provide an advanced computer architecture that efficiently processes a vast quantity of data. With the unique characteristic of memristor, a memristive crossbar array has been utilized for realization of nonvolatile memory, logic-in-memory circuit, and neuromorphic system. However, the crossbar array architecture suffers from leakage of current, known as the sneak current, which causes a cross-talk interference problem between adjacent memristor devices, leading to an unavoidable operational error and high power consumption.

Early experience of laparoscopic resection and comparison with open surgery for gastric gastrointestinal stromal tumor: a multicenter retrospective study.

The advantages of laparoscopic resection over open surgery in the treatment of gastric gastrointestinal stromal tumor (GIST) are not conclusive. This study aimed to evaluate the postoperative and oncologic outcome of laparoscopic resection for gastric GIST, compared to open surgery. We retrospectively reviewed the prospectively collected database of 1019 patients with gastric GIST after surgical resection at 13 Korean and 2 Japanese institutions.

A simple segmentation and quantification method for numerical quantitative analysis of cells and tissues.

Background: Microscopic image analysis based on image processing is required for quantitative evaluation of decellularization. Existing methods are not widely used because of expensive commercial software, and machine learning-based techniques lack generality for decellularization because many high-resolution image data has to be processed.

Objective: In this study, we developed an image processing algorithm for quantitative analysis of tissues and cells in a general microscopic image.

A simple method for removing initial irregularity of an electrocardiogram during a transient state of a power supply in a defibrillator.

Background: The defibrillator is a device that instantaneously discharges the high energy stored in the capacitor to the human body to help revitalize the heart. The circuit for charging the capacitor uses the same power source as the biosignal measurement unit. Therefore, variation in main power supply voltage, ground noise, and electromagnetic interference from the charging circuit can induce distortion into the biosignal at the initial stage of charging.

Multicenter Phase 2 Study about the Safety of No Antimicrobial Prophylaxis Use in Low-Risk Patients Undergoing Laparoscopic Distal Gastrectomy for Gastric Carcinoma (KSWEET-01 Study).

Background: Recent studies have shown a lower risk of surgical site infections (SSI) after laparoscopic distal gastrectomy compared to open surgery. This is a phase 2 study aiming to determine the incidence of SSI after laparoscopic distal gastrectomy without using antimicrobial prophylaxis (AMP).

Methods: cT1N0 gastric cancers that were subject to laparoscopic distal gastrectomy were enrolled.

Long-Term Surgical Outcome of 1057 Gastric GISTs According to 7th UICC/AJCC TNM System: Multicenter Observational Study From Korea and Japan.

The aim of this study was to evaluate the treatment and prognosis of gastric gastrointestinal stromal tumors (GISTs) according to the 7th UICC/AJCC tumor-node-metastasis (TNM) system and the modified National Institutes of Health (NIH) risk classification. The study cohort consisted of 1057 patients with gastric GIST who underwent surgery between January 2000 and December 2007 from 13 institutions in Korea and 2 in Japan. Clinicopathologic characteristics, surgical outcomes, recurrence, and 5-year recurrence-free survival were evaluated.

Effect of visceral fat area on outcomes of laparoscopyassisted distal gastrectomy for gastric cancer: subgroup analysis by gender and parameters of obesity.

Purpose: The aim of this study was to investigate the impact of the visceral fat area (VFA) of patients with gastric cancer undergoing laparoscopic surgery on operative outcomes such as number of retrieved lymph nodes (LNs) and operative time.

Methods: We retrospectively reviewed the medical records and the CT scans of 597 patients with gastric cancer who underwent laparoscopy assisted distal gastrectomy (LADG) with partial omentectomy and LN dissection (>D1 plus beta). Patients were stratified by gender, VFA, and body mass index (BMI), and the clinicopathologic characteristics and operative outcomes were evaluated.

Role of percutaneous transhepatic biliary drainage in patients with complications after gastrectomy.

Objective: The aim of this study was to elucidate the role of PTBD in patients with DSL and ALS post-gastrectomy for malignancy or benign ulcer perforation.

Summary Of Background Data: Percutaneous transhepatic biliary drainage (PTBD) is an interventional radiologic procedure used to promote bile drainage. Duodenal stump leakage (DSL) and afferent loop syndrome (ALS) can be serious complications after gastrectomy.

Risk factors associated with multiple and missed gastric neoplastic lesions after endoscopic resection: prospective study at a single institution in south Korea.

Background/aims: Only a small part of visible gas tric mucosal lesion can be removed by endoscopic resection. This study is aimed to identify incidence rate and associated risk factors of multiple and missed gastric lesions, and proper timing of follow-up en doscopy.

Methodology: Endoscopic surveillance was performed on 1 week, and 1, 6, 12 months af ter endoscopic resection.

The differences in clinicopathological features and prognosis among the subtypes of signet ring cell, mucinous, papillary, and lymphoepithelioma-like carcinoma in advanced gastric cancer.

Background/aims: There are differing histologic subtypes of gastric cancer. We investigated the clinicopathological features and prognosis of: signet ring cell (SRC), mucinous (MGC), papillary (PGC), and lymphoepithelioma-like (LELC) carcinoma in advanced gastric cancer.

Methodology: One hundred thirty six advanced gastric cancer patients, including 62 SRCs, 43 MGCs, 9 PGCs, and 22 LELCs, who underwent R0 gastrectomy between 2002 and 2013, were retrospectively evaluated.

How much progress has been made in minimally invasive surgery for gastric cancer in Korea?: a viewpoint from Korean prospective clinical trials.

Gastric cancer is the most common cancer in Korea. Because the incidence of gastric cancer is still high even with early detection and because of developments in surgical instruments and technological advances, minimally invasive surgery has rapidly become an accepted treatment for gastric cancer in Korea. Many Korean gastric surgeons have contributed to the rapid adaptation of minimally invasive surgery for gastric cancer: not only the Korean Laparoscopic Gastrointestinal Surgery Study (KLASS) group, but also other expert surgeons after the 2000s.

Risk factors for duodenal stump leakage after gastrectomy for gastric cancer and management technique of stump leakage.

Background/aims: The goal of this study was to elucidate the risk factors for duodenal stump leakage after gastrectomy for gastric cancer. In addition, the management of duodenal stump leakage is reviewed.

Methodology: From January 2002 through December 2012, 1,195 patients with gastric cancer who underwent gastric R0 resection were enrolled in this study.

Comprehension of readmission after laparoscopy assisted distal gastrectomy: what are the causes?

Purpose: The aim of this study is to evaluate long-term outcomes regarding readmission for laparoscopy-assisted distal subtotal gastrectomy (LADG) compared to conventional open distal subtotal gastrectomy (CODG) for early gastric cancer (EGC).

Methods: Between January 2003 and December 2006, 223 and 106 patients underwent LADG and CODG, respectively, for EGC by one surgeon. The clinicopathologic characteristics, postoperative outcomes, postoperative complications, overall 5-year survival, recurrence, and readmission were retrospectively compared between the two groups.

Is the rate of postoperative complications following laparoscopy-assisted gastrectomy higher in elderly patients than in younger patients?

Background: With an increase in life expectancy, very elderly patients are presenting with gastric cancer more commonly than ever. The present study retrospectively analyzed the surgical outcomes of laparoscopy-assisted gastrectomy for gastric cancer in the young, elderly, and very elderly age groups.

Methods: The study group consisted of 1,055 patients who underwent laparoscopy-assisted gastrectomy between February 2002 and December 2012.

Analysis of prognostic factors and outcomes of gastric cancer in younger patients: a case control study using propensity score methods.

Aim: To understand the clinicopathological and prognostic features of gastric cancer in younger and older patients.

Methods: Between January 2002 and December 2008, 1667 patients underwent curative gastric surgery. For comparative purposes, the patients were divided into two groups: younger patients who were less than 40 years old (112 patients), and older patients who were 40 years old and older (1555 patients).

Prognostic significance of thymidylate synthase, thymidine phosphorylase and dihydropyrimidine dehydrogenase expression in biliary tract cancer patients receiving adjuvant 5-fluorouracil-based chemotherapy.

Biliary tract cancer (BTC) is a relatively uncommon type of cancer, accounting for ∼4% of the malignant neoplasms of the gastrointestinal tract. The aim of this study was to determine whether the expression of thymidylate synthase (TS), thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD) predict clinical outcome in BTC patients treated with adjuvant 5-fluorouracil (5-FU)-based chemotherapy. TS and TP expression were found to be significantly correlated with cancer location (P=0.

Light shutter using dichroic-dye-doped long-pitch cholesteric liquid crystals.

We propose a light shutter device using dichroic-dye-doped liquid crystals (LCs) whose Bragg reflection wavelength is set to be infrared by controlling the pitch of cholesteric liquid crystals (ChLCs). A dye-doped long-pitch ChLC cell is switchable between the dark planar state and the transparent homeotropic state. It has the advantages of high transmittance, low operation voltage, and an easy fabrication process relative to previous LC light shutter devices.

Readmissions following elective radical total gastrectomy for early gastric cancer: a case-controlled study.

Background: Readmission after gastrectomy is one of the factors that reflect quality of life. Therefore, we analyzed the several factors related to readmissions after total gastrectomy for early gastric cancer.

Methods: From January 2002 through December 2009, 102 consecutive patients who underwent radical total gastrectomy for early gastric cancer were enrolled in this study.

Is laparoscopy-assisted total gastrectomy feasible for the treatment of gastric cancer? A case-matched study.

Background: The aim of this study was to clarify the short- and long-term outcomes of laparoscopy-assisted total gastrectomy (LATG) for gastric cancer compared to conventional open total gastrectomy (COTG) with a case-control study.

Methods: Between January 2002 and December 2010, a series of 264 patients with gastric cancer underwent R0 total gastrectomy (61 LATG patients and 203 COTG patients). Age, gender, and pathological stage were matched by propensity scoring, and 120 patients (60 LATG and 60 COTG) were selected for analysis.

Prognostic significance of neutrophil lymphocyte ratio and platelet lymphocyte ratio in advanced gastric cancer patients treated with FOLFOX chemotherapy.

Background: Several inflammatory response materials could be used for prediction of prognosis of cancer patients. The neutrophil lymphocyte ratio (NLR), and the platelet lymphocyte ratio (PLR) have been introduced for prognostic scoring system in various cancers. The objective of this study was to determine whether the NLR or the PLR would predict the clinical outcomes in advanced gastric cancer patients treated with oxaliplatin/ 5-fluorouracil (FOLFOX).

In-plane switching of vertically aligned negative liquid crystals for high transmittance and wide viewing angle.

We propose a method for in-plane switching of vertically aligned negative liquid crystals (LCs) for high transmittance and wide viewing angle. By applying an in-plane electric field using a double-layered electrode structure, LC molecules can be rotated by the vertical as well as the in-plane components of the applied field over the entire region so that high transmittance can be achieved. The threshold voltage difference can be obtained simply by varying the electrode structure, which can reduce the off-axis gamma shift in a multidomain vertical alignment LC cell.

Association between phosphorylated AMP-activated protein kinase and MAPK3/1 expression and prognosis for patients with gastric cancer.

Objectives: Phosphorylated AMP-activated protein kinase (pAMPK) plays a central role in cellular metabolic sensing and energy balance homeostasis, and interacts with various pathways [e.g., TP53, mTOR, NUAK2 (sucrose nonfermenting-like kinase), MAPK3/1 (ERK) and PDK].

Fascin expression is related to poor survival in gastric cancer.

Fascin is an actin-binding protein that provides mechanical support and cell motility, and involves cancer cell metastasis. We investigated fascin protein expression in gastric cancer and assessed their relationship with clinicopathologic parameters and survival rates. In addition, we researched galectin-3 protein expression to study fascin action mechanisms.

Dual mode switching of cholesteric liquid crystal device with three-terminal electrode structure.

We propose a cholesteric liquid crystal device with a three-terminal electrode structure that can be operated in both the dynamic and the bistable modes. Fast switching (less than 5 ms) between the planar and the in-plane-field-induced states can be realized by applying an in-plane electric field, and conventional bistable switching between the planar and focal conic states can be realized by applying a vertical electric field.