Assessing biofilm formation and resistance of vibrio parahaemolyticus on UV-aged microplastics in aquatic environments.

UV degradation of marine microplastics (MPs) could increase their vector potential for pathogenic bacteria and threaten human health. However, little is known about how the degree of UV aging affects interactions between MPs and pathogens and how various types of MPs differ in their impact on seafood safety. This study investigated five types of UV-aged MPs and their impact on Vibrio parahaemolyticus, a seafood pathogen. MPs exposed to UV for 60 days showed similar physicochemical changes such as surface cracking and hydrophobicity reduction. Regardless of the type, longer UV exposure of MPs resulted in more biofilm formation on the surface under the same conditions. V. parahaemolyticus types that formed biofilms on the MP surface showed 1.4- to 5.0-fold upregulation of virulence-related genes compared to those that did not form biofilms, independently of UV exposure. However, longer UV exposure increased resistance of V. parahaemolyticus on MPs to chlorine, heat, and human gastrointestinal environment. This study implies that the more UV degradation occurs on MPs, the more microbial biofilm formation is induced, which can significantly increase virulence and environmental resistance of bacteria regardless of the type of MP.

Reconfigurable Multilevel Optical PUF by Spatiotemporally Programmed Crystallization of Supersaturated Solution.

Physical unclonable functions (PUFs) are emerging as an alternative to information security by providing an advanced level of cryptographic keys with non-replicable characteristics, yet the cryptographic keys of conventional PUFs are not reconfigurable from the ones assigned at the manufacturing stage and the overall authentication process slows down as the number of entities in the dataset or the length of cryptographic key increases. Herein, a supersaturated solution-based PUF (S-PUF) is presented that utilizes stochastic crystallization of a supersaturated sodium acetate solution to allow a time-efficient, hierarchical authentication process together with on-demand rewritability of cryptographic keys. By controlling the orientation and the average grain size of the sodium acetate crystals via a spatiotemporally programmed temperature profile, the S-PUF now includes two global parameters, that is, angle of rotation and divergence of the diffracted beam, in addition to the speckle pattern to produce multilevel cryptographic keys, and these parameters function as prefixes for the classification of each entity for a fast authentication process. At the same time, the reversible phase change of sodium acetate enables repeated reconfiguration of the cryptographic key, which is expected to offer new possibilities for a next-generation, recyclable anti-counterfeiting platform.

Screening of Carbofuran-Degrading Bacteria Chryseobacterium sp. BSC2-3 and Unveiling the Change in Metabolome during Carbofuran Degradation.

Carbofuran is one of the most commonly used N-methylcarbamate-based pesticides and is excellent for controlling pests; however, carbofuran also causes soil and water pollution. Although various studies have been conducted on the bioremediation of pesticide-contaminated soil, the changes occurring in the metabolome during the bioremediation of carbofuran are not fully understood. In this study, the intracellular and extracellular metabolites of the Chryseobacterium sp. BSC2-3 strain were analysed during carbofuran degradation by using a liquid chromatography-mass spectrometry-based metabolomics approach. We found that the BSC2-3 strain extracellularly transformed carbofuran into 3-hydroxycarbofuran. Intracellular metabolite analysis revealed that carbofuran mainly affected aminobenzoate degradation, ubiquinone and terpenoid-quinone biosynthesis, and arginine and proline metabolism. Carbofuran especially affected the metabolic pathway for the degradation of naphthalene and aminobenzoate. Metabolomics additionally revealed that the strain produces disease resistance inducers and plant growth regulators. We also identified the genes involved in the production of indole-3-acetic acid, which is one of the most active auxins. Overall, we identified the metabolic changes induced in carbofuran-degrading bacteria and the genes predicted to be responsible for the degradation of carbofuran.

Transarterial Radioembolization for Unresectable Hepatocellular Carcinoma: Real-Life Efficacy and Safety Analysis of Korean Patients.

Transarterial radioembolization (TARE) has become widely used in the treatment of HCC, one of the most common causes of cancer mortality worldwide. Here we investigated the long-term clinical outcomes of patients with hepatocellular carcinoma (HCC) treated with TARE in a multi-medical center in Korea. A total of 149 patients treated with TARE from 2008-2014 were recruited. The pre-treatment HCC stage was classified according to the BCLC stage, of which C and D were defined as advanced HCC. Advanced HCC stage and Child-Turcotte-Pugh (CTP) score A were identified in 62 (42%) and 134 (90%) patients, respectively. Portal vein thrombosis (PVT) was identified in 58 patients (38.9%). The median time to progression (TTP) was 14 months, and the median overall survival (OS) and progression-free survival (PFS) were 18.6 and 8.9 months, respectively. The overall tumor response was 47%, and the disease control rate was 78%. OS and PFS differed significantly according to the presence of liver cirrhosis, extrahepatic metastasis, tumor response and curative treatment after TARE (all, p < 0.05). Multiple tumors and major PVT were other independent factors related to OS, while the des-gamma carboxy protein level predicted PFS (all, p < 0.05). Tumor size was an independent predictor of tumor response. TTP, OS and PFS all differed among BCLC stages. The serious adverse effect after TARE was clinically not significant. Therefore, TARE is safe and effective in treating early to advanced HCCs.

Fabrication of Perforated PDMS Microchannel by Successive Laser Pyrolysis.

Poly(dimethylsiloxane) has attracted much attention in soft lithography and has also been preferred as a platform for a photochemical reaction, thanks to its outstanding characteristics including ease of use, nontoxicity, and high optical transmittance. However, the low stiffness of PDMS, an obvious advantage for soft lithography, is often treated as an obstacle in conducting precise handling or maintaining its structural integrity. For these reasons, a Glass-PDMS-Glass structure has emerged as a straightforward alternative. Nevertheless, several challenges are remaining in fabricating Glass-PDMS-Glass structure through the conventional PDMS patterning techniques such as photolithography and etching processes for master mold. The complicated techniques are not suitable for frequent design modifications in research-oriented fields, and fabrication of perforated PDMS is hard to achieve using mold replication. Herein, we utilize the successive laser pyrolysis technique to pattern thin-film PDMS for microfluidic applications. The direct use of thin film at the glass surface prevents the difficulties of thin-film handling. Through the precise control of photothermal pyrolysis phenomena, we provide a facile fabrication process for perforated PDMS microchannels. In the final demonstration, the laminar flow has been successfully created owing to the smooth surface profile. We envision further applications using rapid prototyping of the perforated PDMS microchannel.

Bacterial protoplast-derived nanovesicles as vaccine delivery system against bacterial infection.

The notion that widespread infectious diseases could be best managed by developing potent, adjuvant-free vaccines has resulted in the use of various biological immune-stimulating components as new vaccine candidates. Recently, extracellular vesicles, also known as exosomes and microvesicles in mammalian cells and outer membrane vesicles in Gram-negative bacteria, have gained attention for the next generation vaccine. However, the more invasive and effective the vaccine is in delivery, the more risk it holds for severe immune toxicity. Here, in optimizing the current vaccine delivery system, we designed bacterial protoplast-derived nanovesicles (PDNVs), depleted of toxic outer membrane components to generate a universal adjuvant-free vaccine delivery system. These PDNVs exhibited significantly higher productivity and safety than the currently used vaccine delivery vehicles and induced strong antigen-specific humoral and cellular immune responses. Moreover, immunization with PDNVs loaded with bacterial antigens conferred effective protection against bacterial sepsis in mice. These nonliving nanovesicles derived from bacterial protoplast open up a new avenue for the creation of next generation, adjuvant-free, less toxic vaccines to be used to prevent infectious diseases.

Gastroprotective effect of Cochinchina momordica seed extract in nonsteroidal anti-inflammatory drug-induced acute gastric damage in a rat model.

BACKGROUND/AIMS: The major compounds of Cochinchina momordica seed extract (SK-MS10) include momordica saponins. We report that the gastroprotective effect of SK-MS10 in an ethanol-induced gastric damage rat model is mediated by suppressing proinflammatory cytokines and downregulating cytosolic phospholipase A2 (cPLA2), 5-lipoxygenase (5-LOX), and the activation of calcitonin gene-related peptide. In this study, we evaluated the gastroprotective effects of SK-MS10 in the nonsteroidal anti-inflammatory drug (NSAID)-induced gastric damage rat model. METHODS: The pretreatment effect of SK-MS10 was evaluated in the NSAID-induced gastric damage rat model using aspirin, indomethacin, and diclofenac in 7-week-old rats. Gastric damage was evaluated based on the gross ulcer index by gastroenterologists, and the damage area (%) was measured using the MetaMorph 7.0 video image analysis system. Myeloperoxidase (MPO) was measured by enzyme-linked immunosorbent assay, and Western blotting was used to analyze the levels of cyclooxygenase (COX)-1, COX-2, cPLA2, and 5-LOX. RESULTS: All NSAIDs induced gastric damage based on the gross ulcer index and damage area (p<0.05). Gastric damage was significantly attenuated by SK-MS10 pretreatment compared with NSAID treatment alone (p<0.05). The SK-MS10 pretreatment group exhibited lower MPO levels than the diclofenac group. The expression of cPLA2 and 5-LOX was decreased by SK-MS10 pretreatment in each of the three NSAID treatment groups. CONCLUSIONS: SK-MS10 exhibited a gastroprotective effect against NSAID-induced acute gastric damage in rats. However, its protective mechanism may be different across the three types of NSAID-induced gastric damage models in rats.

Correlation between Endoscopic and Histological Diagnoses of Gastric Intestinal Metaplasia.

BACKGROUND/AIMS: Intestinal metaplasia (IM) is a premalignant condition. This study aimed to evaluate the correlation between endoscopic and histological findings of IM. METHODS: The cases of IM were graded by conventional endoscopy, and biopsies were taken from the antrum and body of 1,333 subjects for histological IM diagnosis. Multivariate analyses were performed to identify the factors that affect the sensitivity of endoscopic IM diagnosis. RESULTS: The sensitivity/specificity of endoscopic IM diagnosis based on histology was 24.0%/91.9% for the antrum and 24.2%/88.0% for the body. As indicated by multivariate analysis, the presence of endoscopic atrophic gastritis (AG) (odds ratio [OR], 4.73; 95% confidence interval [CI], 2.07 to 10.79) and the activity of mucosal inflammation (OR, 2.21; 95% CI, 1.08 to 4.54) were associated with the sensitivity of endoscopic IM diagnosis in the antrum, while the presence of endoscopic AG (OR, 8.02; 95% CI, 4.55 to 14.15), dysplasia (OR, 2.40; 95% CI, 1.07 to 5.39), and benign gastric ulcers (OR, 0.35; 95% CI, 0.15 to 0.081) were associated with the sensitivity of endoscopic IM diagnosis in the body. CONCLUSIONS: As the sensitivity of endoscopic IM diagnosis was low, a high index of suspicion for IM is necessary in the presence of atrophy, and confirmation by histology is also necessary.

Comparison of gastroesophageal reflux disease symptoms and proton pump inhibitor response using gastroesophageal reflux disease impact scale questionnaire.

BACKGROUND/AIMS: To compare gastroesophageal reflux disease (GERD) symptoms and response to proton pump inhibitor (PPI) in patients with erosive esophagitis (EE), non-erosive reflux disease (NERD) or functional heartburn (FH) using GERD impact scale (GIS) questionnaire. METHODS: Total 126 patients with GERD symptoms were diagnosed as EE (n = 62), NERD (n = 34) and FH (n = 30) by endoscopy, 24-hour esophageal pH testing and Bernstein test, prospectively. Analysis of risk factors and GIS questionnaire for GERD symptoms and quality of life were performed before and 8 weeks after PPI treatment. RESULTS: EE group had a higher proportion of men, frequent alcohol consumption, smoking, hiatal hernia, body mass index ≥ 25 kg/m(2) and triglyceride levels (≥ 150 mg/dL) than the other groups (all P < 0.05). On the other hand, both psychiatric treatment and psychopharmacotherapy were more frequent in patients with FH than in those with EE and NERD (both P < 0.05). Among GERD symptoms, chest pain was more frequent in FH group than in EE and NERD groups (P < 0.05). Eating problems and limitation of productive daily activities occurred frequently in FH group and NERD group, respectively. GIS after 8 week PPI treatment showed improvement in all of the GERD symptoms in EE (all P < 0.05) and in acid regurgitation, epigastric pain and hoarseness in NERD group (all P < 0.05). In terms of quality of life, PPI treatment improved sleep disturbance in EE (P = 0.031) and limitation of productive activity in the NERD group (P = 0.001). CONCLUSIONS: GIS questionnaire showed that different characteristics and symptoms improved after PPI therapy among patients with EE, NERD and FH, demonstrating the usefulness of the GIS questionnaire.

[Comparison among conventional 4 L polyethylene glycol, split method of 4 L polyethylene glycol and combination of 2 L polyethylene glycol and sodium phosphate solution for colonoscopy preparation].

BACKGROUND/AIMS: The aim of this study was to compare polyethylene glycol (PEG) 4 L, split method of PEG 4 L and PEG 2 L plus sodium phosphate (NaP) in the aspect of bowel preparation quality, safety, patients' compliance and preference. METHODS: Total 249 subjects were prospectively enrolled and received bowel preparation for colonoscopy from August to October in 2010; PEG 4 L (93 subjects), split method of 4 L PEG (74 subjects) and PEG 2 L plus NaP 90 mL group (82 subjects). To investigate the completion, preference for bowel preparation and safety, a questionnaire survey was conducted before colonoscopy. RESULTS: There were no significant intergroup differences in the aspect of completion of preparation, cecal intubation time and success rate. Satisfaction and preference were higher in PEG 2 L plus NaP 90 mL and split method of 4 L PEG compared with PEG 4 L. In the aspect of the bowel preparation quality PEG 4 L showed significantly higher quality in the morning colonoscopy (p<0.001). However, in the afternoon colonoscopy PEG 2 L plus NaP 90 mL showed better result than PEG 4 L (p=0.009). Hyperphosphatemia was most frequently observed in PEG 2 L plus NaP 90 mL, but no severe adverse events occurred (p<0.001). CONCLUSIONS: PEG 4 L showed better result than split method of 4 L PEG or PEG 2 L plus NaP 90 mL in the aspect of bowel preparation quality and safety.

Fraction of exhaled nitric oxide in patients with acute eosinophilic pneumonia.

BACKGROUND: Acute eosinophilic pneumonia (AEP) is an idiopathic disease characterized by pulmonary eosinophilia. Because the fraction of exhaled nitric oxide (Feno) is a surrogate of eosinophilic inflammation, we evaluated the levels, changed treatments, and the diagnostic role of Feno in patients with AEP. METHODS: Between June 2010 and March 2011, we prospectively enrolled patients at the Armed Forces Capital Hospital who had pulmonary infiltrates and a febrile illness and who were clinically suspected to have AEP. We measured Feno twice at the initial visit (pretreatment) and 2 weeks after the initial measurement (posttreatment). RESULTS: A total of 60 subjects were enrolled, and 31 were given a diagnosis of AEP. The pretreatment Feno levels of the patients with AEP were significantly higher than those of the patients without AEP (median, 48 parts per billion [ppb] [range, 10-138] vs 14 ppb [range, 5-41]; P < .001). The cut-off value (23.5 ppb) showed that the maximal area under the receiver operating characteristic curve predicted AEP with a sensitivity of 0.87 and a specificity of 0.83. The posttreatment Feno levels decreased significantly in the patients with AEP, and the levels were similar to the patients without AEP (median, 19 ppb [range, 7-44] vs 14 ppb [range, 1-58]; P = .21) CONCLUSIONS: The Feno level was significantly higher in patients with AEP than in those without AEP. Feno measurement can be used as a diagnostic tool to differentiate patients with AEP from those without AEP. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01152424; URL: www.clinicaltrials.gov.