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Previously, we reported the one-pot synthesis of polyacetylene (PA) diblock copolymers which formed various nanostructures via the in situ nanoparticlization of conjugated polymers (INCP), using a two-step protocol based on sequential monomer addition. Herein, we report a much simpler one-shot method for nanostructure formation by the synthesis of PA blocklike copolymers. The blocklike copolymers could be prepared by the one-shot ROMP of comonomers with large differences in their reactivities because the monomers that formed the first block, namely norbornene (NB) derivatives or endo-tricyclo[4.2.2.0]deca-3,9-diene (TD) derivatives, polymerized much faster than the monomers that formed the second PA block, cyclooctatetraene (COT). Owing to their blocklike microstructures, the copolymers formed various nanostructures such as nanospheres, nanocaterpillars, and nanoaggregates depending on the chemical structures of the soluble shell polymers and feed ratio of COT, which formed the insoluble PA core. Using dynamic light scattering (DLS) and atomic force microscopy (AFM), it was observed that the nanostructures produced from the blocklike copolymers were essentially the same as those produced from the block copolymers synthesized by conventional sequential monomer addition. The blocklike microstructures of the copolymers formed by one-shot ROMP were further supported by an in situ ¹H NMR kinetic experiment and UV/vis spectroscopy. From these results, we were able to confirm that the ROMP of TD and COT produced near-perfect block copolymers. Furthermore, the 1H NMR spectra of the one-shot copolymerization provided insights into the INCP process. [ABSTRACT FROM AUTHOR]

We report a direct one-pot route for the preparation of supramolecules from simple polyacetylene diblock copolymers synthesized by mild ring-opening metathesis polymerization of cyclooctatetraene. This in situ nanoparticlization of conjugated polymer (INCP) approach is advantageous over conventional self-assembly processes because this method does not require any tedious postsynthetic treatments. Also, this direct approach provides intriguing supramolecules with a unique nanostructure resembling a caterpillar. Furthermore, the new supramolecules are highly stable adducts because the polyacetylene core block provides an exceptionally strong driving force for the self-assembly. Even though pristine polyacetylene is unstable in air, the polyacetylene segment in the nanocaterpillar is very stable because it is protected within the shell of the supramolecule. [ABSTRACT FROM AUTHOR]

We proposed a rapid method to estimate the efficacies of air controlling devices in situ using ATP bioluminescence in combination with an inertial impactor. The inertial impactor was designed to have 1 μm of cutoff diameter, and its performance was estimated analytically, numerically, and experimentally. The proposed method was characterized using Staphylococcus epidermidis, which was aerosolized with a nebulizer. The bioaerosol concentrations were estimated within 25 min using the proposed method without a culturing process, which requires several days for colony formation. A linear relationship was obtained between the results of the proposed ATP method (RLU/m³) and the conventional culture-based method (CFU/m³), with R² 0.9283. The proposed method was applied to estimate the concentration of indoor bioaerosols, which were identified as a mixture of various microbial species including bacteria, fungi, and actinomycetes, in an occupational indoor environment, controlled by mechanical ventilation and an air cleaner. Consequently, the proposed method showed a linearity with the culture-based method for indoor bioaerosols with R² 0.8189, even though various kinds of microorganisms existed in the indoor air. The proposed method may be effective in monitoring the changes of relative concentration of indoor bioaerosols and estimating the effectiveness of air control devices in indoor environments. [ABSTRACT FROM AUTHOR]

Silver aerosol nanoparticles generated by an atomizer were investigated as an antimicrobial agent against B. subtilis bioaerosols, a model for Gram-positive bacteria. The bioaerosols and silver aerosol nanoparticles were mixed in a test duct for 15 s and sampled on nutrient agar plates by an impactor. Peak concentrations of the silver aerosol nanoparticles at the mobility diameter of 80 nm were controlled from 1.5 105 to 1.0 106 particlescm3, depending on the concentration of silver hydrosol nanoparticles. The maximal antimicrobial efficiency of silver aerosol nanoparticles was 76 under selected experimental conditions. [ABSTRACT FROM AUTHOR]

Even though activated carbon fiber (ACF) filters have been widely used in air cleaning for the removal of hazardous gaseous pollutants, because of their extended surface area and high adsorption capacity, bacteria may breed on the ACF filters as a result of their good biocompatibility; ACF filters can themselves become a source of bioaerosols. In this study, silver particles were coated onto an ACF filter, using an electroless deposition method and their efficacy for bioaerosol removal was tested. First, various surface analyses, including scanning electron microscopy, inductively coupled plasma and X-ray diffraction were carried out to characterize the prepared ACF filters. Filtration and antimicrobial tests were then performed on the filters. The results showed that the silver-deposited ACF filters were effective for the removal of bioaerosols by inhibition of the survival of microorganisms, whereas pristine ACF filters were not Two bacteria, Bacillus subtilis and Escherichia coli, were completely inhibited within 10 and 60 mm, respectively. Electroless silver deposition did not influence the physical characteristics of ACF filters such as pressure drop and filtration efficiency. The gas adsorptive ability of the silver-deposited ACF filter, as represented by the micropore specific surface area, decreased by about 20% compared to the pristine filter because of the blockage of the ACF micropores by silver particles. Therefore, the amount of silver particles on the ACF filters needs to be optimized to avoid excessive reduction of their adsorptive characteristics and to show effective antimicrobial activity. [ABSTRACT FROM AUTHOR]

The surgical indications for the treatment of gastroesophageal reflux disease (GERD) in patients with esophageal motility disorders have been debated. We report a case of antireflux surgery performed in a patient with absent esophageal motility as categorized by the Chicago classification (2011). A 54-year-old man underwent laparoscopic Toupet fundoplication due to apparent GERD and desire to discontinue all medications. After surgery, his subjective symptoms improved. Furthermore, objective findings including manometry and 24- hour pH-metry also improved. In our experience, antireflux surgery can improve GERD symptoms patients, even with absent esophageal motility. [ABSTRACT FROM AUTHOR]

Nanostar and nanonetwork crystals were prepared from fully conjugated poly(3-(2-ethylhexyl)thiophene)-block-polythiophene (P3EHT-b-PT) via a simple INCP process. The structural conformation of the nanocrystals was investigated in detail, revealing that with an increase in the block length of PT, the morphology of the nanocrystals changed from nanospheres to nanorods, nanostars, and to nanonetworks. [ABSTRACT FROM AUTHOR]

Purpose: With an increase in life expectancy, more elderly patients are presenting with gastric cancer. As a result it is yet be resolved whether laparoscopy assisted distal gastrectomy is a suitable treatment for elderly patients with early gastric cancer. This study retrospectively compared surgical outcomes of laparoscopy assisted distal gastrectomy between elderly and nonelderly patients with gastric cancer. Materials and Methods: The study group was comprised of 316 patients who underwent laparoscopy assisted distal gastrectomy between April 2005 and December 2010. Of these patients, 93 patients whose ages were 65 years or more were compared with 223 patients who were younger. Results: There were no differences in the short term outcome or minor complication rate between the elderly patients and the nonelderly patients. The hospital stay was significantly longer and the major complication rate was significantly higher for the elderly patients compared with nonelderly patients. Conclusions: Laparoscopy assisted distal gastrectomy for early gastric cancer in the elderly patients had comparable operation time and blood loss with the nonelderly group. However, the safety and advantage of laparoscopy assisted distal gastrectomy in the elderly patients need to be further studied in higher volume trials. [ABSTRACT FROM AUTHOR]

There is great interest in the fabrication of micro- and nanopatterned metallic structures on substrates for a wide range of electronic, photonic, and magnetic devices. One of the most widely used techniques is the electroless deposition (ELD) of metal, which requires the surface activation of the substrates with a metal catalyst. This paper introduces a method of catalytic surface activation by producing platinum aerosol nanoparticles via spark generation and then thermophoretically depositing the particles onto a flexible polyimide (PI) substrate through the pattern hole of a mask. After annealing, the catalytically activated substrate is placed into a solution for electroless silver deposition. The silver is then formed only on the activated regions of the substrate. Silver line patterns having a width of 18 µm and a height of 1 µm are created with the ability to be effectively reproduced. The average value of the resistivities is approximately 6.8 μΩ·cm, which is almost comparable to the theoretical resistivity of bulk silver (1.6 μΩ·cm). Other silver micropatterns containing square dot array, line, line array, Y-branched line, and tapered line using different pattern masks are also demonstrated. [ABSTRACT FROM AUTHOR]

Introduction: Petersen’s hernia (PH) is a potentially fatal complication of bowel infarction that is difficult to treat by laparoscopic reduction. Aim: To define predictive computed tomography (CT) profiles to identify PH patients who would be suitable for laparoscopic reduction by a comparative analysis between patients treated by laparoscopic and open reduction. Material and methods: We retrospectively collected the clinical data of patients (n = 28) who underwent PH reduction surgery after minimally invasive gastrectomy for gastric cancer in the period 2015–2018 at four training hospitals. We examined the preoperative CT scans to identify the indications for laparoscopic PH reduction. Results: We compared the laparoscopic reduction group (laparoscopic group, n = 15) and the open reduction group (open group, n = 13). Patients in the laparoscopic group were younger (55.7 ±10.4) than those in the open group (69.3 ±9.1), but there were no differences in clinical or laboratory findings. We found that there were two CT profiles with significant differences between the open and laparoscopic groups: superior mesenteric vein (SMV) narrowing and small bowel dilation. We found that small bowel dilatation was an independent factor on multivariate analysis for laparoscopic PH reduction. Conclusions: We found that small bowel dilatation is the most important CT profile for identifying PH patients contraindicated for laparoscopic reduction. Despite the retrospective design of this study, these CT profiles are expected to define the scope of laparoscopic reduction in PH patients and to establish indications for the laparoscopic approach. [ABSTRACT FROM AUTHOR]

Background and Objectives: This study aimed to evaluate the efficacy of post-operative oral nutrition supplementation after major gastrointestinal surgery.Methods and Study Design: A prospective randomized controlled trial was conducted to evaluate 174 subjects who were discharged within 2 weeks after major gastrointestinal surgery. The subjects in the study group were prescribed 400 ml/day of Encover® from the day of discharge for 8 weeks, but no supplementation was allowed in the control group. The primary endpoint was the weight loss rate at 8 weeks after discharge compared with the pre-operative weight, and the secondary endpoints included changes in body weight, body mass index, Patient-Generated Subjective Global Assessment score/grade, hematological/ biochemical parameters, and adverse events evaluated at 2, 4, and 8 weeks after discharge.Results: The weight loss rate at 8 weeks after discharge did not differ between two groups (4.23±5.49% vs 4.80±4.84%, p=0.481). The total lymphocyte count, the level of total cholesterol, total protein, and albumin were significantly higher in the study group after discharge. Diarrhea was the most frequent adverse event, and the incidence of adverse events with a severity score of >=3 did not differ between groups (2.3% vs 1.2%).Conclusions: The utility of routine oral nutritional support after major gastrointestinal surgery was not proven in terms of weight loss at 8 weeks after discharge. However, it can be beneficial for early recovery of biochemical parameters. [ABSTRACT FROM AUTHOR]

Purpose: At present, a human epidermal growth factor receptor 2 (HER2)-based concept of tumor biology has been established, and trastuzumab (Herceptin®; Genentech/Roche, San Francisco, CA, USA), a monoclonal humanized antibody directed against HER2, is a pivotal agent for the management of HER2 positive (HER2+) metastatic breast cancer. It is also known that HER2 has a predictive value in gastric cancer; however, its association with the prognosis of this disease remains uncertain. The purpose of this study was to evaluate both the relationship between HER2 overexpression in the tumors of gastric cancer patients, and the prognosis of these patients who have had curative resection. Materials and Methods: A total of 139 consecutive patients with gastric cancer who underwent surgery at the Kosin University Gospel Hospital between October 2011 and March 2012 were included in this retrospective study. All tumor samples were examined for HER2 expression by immunohistochemistry. A retrospective review of the medical records was conducted to determine the correlation between the presence of HER2 overexpression and clinicopathological factors. Results: The HER2+ rate was 15.1%. HER2 overexpression was associated with histological grade (P=0.044) and Lauren classification (P=0.036). There was no significant difference in the 2-year overall survival between HER2+ and HER2- patients (P=0.396). Multivariate analysis showed that HER2 was not an independent prognostic factor. Conclusions: HER2 overexpression in tumors was associated with histological grade and Lauren classification in gastric cancer patients with curative resection. However, HER2 was not an independent prognostic factor for gastric cancer in our study. [ABSTRACT FROM AUTHOR]

Purpose: Laparoscopy-assisted distal gastrectomy for early gastric cancer has gained acceptance and popularity worldwide. However, laparoscopy-assisted distal gastrectomy for advanced gastric cancer is still controversial. Therefore, we propose this prospective randomized controlled multi-center trial in order to evaluate the safety and feasibility of laparoscopy assisted D2-gastrectomy for advanced stage gastric cancer. Materials and Methods: Patients undergoing distal gastrectomy for advanced gastric cancer staged cT2/3/4 cN0/1/2/3a cM0 by endoscopy and computed tomography are eligible for enrollment after giving their informed consent. Patients will be randomized either to laparoscopyassisted distal gastrectomy or open distal gastrectomy. Sample size calculation revealed that 102 patients are to be included per treatment arm. The primary endpoint is the non-compliance rate of D2 dissection; relevant secondary endpoints are three-year disease free survival, surgical and postoperative complications, hospital stay and unanimity rate of D2 dissection evaluated by reviewing the intraoperative video documentation. Discussion: Oncologic safety is the major concern regarding laparoscopy-assisted distal gastrectomy for advanced gastric cancer. Therefore, the non-compliance rate of clearing the N2 area was chosen as the most important parameter for the technical feasibility of the laparoscopic procedure. Furthermore, surgical quality will be carefully reviewed, that is, three independent experts will review the video records and score with a check list. For a long-term result, disease free survival is considered a secondary endpoint for this trial. This study will offer promising evidence of the feasibility and safety of Laparoscopy-assisted distal gastrectomy for advanced gastric cancer. Trial Registration: NCT01088204 (international), NCCCTS-09-448 (Korea) [ABSTRACT FROM AUTHOR]

Metastatic leptomeningeal carcinomatosis is estimated to occur in 3% to 8% of solid carcinomas. The most common causes of leptomeningeal carcinomatosis are breast cancer, lung cancer and malignant melanoma. Leptomeningeal carcinomatosis associated with gastric cancer, especially in its early stages, is exceedingly rare. Its presenting symptoms include headache, nauseaand seizures. In this report, we describe a case of leptomeningeal metastasis that presented with early-stage gastric cancer. A 67-year-old woman with a history of early-stage gastric cancer in remission was admitted to our hospital with 3 days of headache and nausea. Her gastric cancer had been treated 29 months prior to presentation by a radical subtotal gastrectomy with a Billroth I anastomosis. She had an uneventful recovery until she was diagnosed with metastases to the left axilla and neck 26 months after surgery. Her presenting symptoms of headache and nausea prompted cytologic examination of the cerebrospinal fluid and measurement of tumor markers, which revealed metastatic leptomeningeal carcinomatosis from her gastric cancer. This report aims to raise awareness of the possibility that even early-stage gastric cancer can lead to leptomeningeal carcinomatosis. [ABSTRACT FROM AUTHOR]