Development of metabolomic biomarkers to discriminate the geographical origin of Korean and Russian snow crabs using CE-TOF/MS.

The quantity of snow crabs (Chionoecetes opilio) harvested in Korea is subject to seasonal restrictions; therefore, snow crabs are imported from Russia. Metabolites in snow crabs from two geographic origins were compared. The metabolites were subjected to metabolomic analysis to prevent fraudulent sales of marine products from a particular country. Capillary electrophoresis time-of-flight mass spectrometry was used. Seventy-seven target metabolites were identified using a mass spectral library. Through orthogonal partial least squares discriminant analysis, the top 25 biomarker candidates were evaluated based on p-values and fold changes. A total of 246 peaks (187 and 59 in the cation and anion modes, respectively) were identified. Among the biomarker candidates, 2-oxovaleric acid, asymmetric dimethylarginine, hypotaurine, and allo-threonine were selected as final biomarkers to unequivocally determine the geographic origin. Overall, metabolic analyses allowed us to differentiate snow crabs from different geographic origins. This method could also be extended of other marine products.

Development of biomarkers to distinguish different origins of red seabreams (Pagrus major) from Korea and Japan by fatty acid, amino acid, and mineral profiling.

Red seabream (Pagrus major) has been one of the most popular fish in East Asia since early times. However, the discharge of nuclear wastewater into the sea following the Fukushima nuclear disaster in Japan has led to violations of the country of origin labeling. Therefore, the aim of the present study was to determine the origin of fish based on fatty acid, amino acid, and mineral analyses, and to develop biomarkers that can discriminate between Japanese and Korean red seabream. To identify the differences between the two groups, 29 fatty acid families, 17 amino acids, and 4 minerals were analyzed in 60 fish samples (standard sample collected in autumn), and fatty acid profiles were analyzed using heatmap with hierarchical clustering analysis and orthogonal projections to latent structures discriminant analysis. The top 10 fatty acids that were different between the two groups were selected from all seasonal fish samples by combining variable importance in projection scores and p-values. According to the receiver operating characteristic curve analysis results, we proposed percentage linoleic acid (C18:2n-6, cis) as a candidate biomarker with excellent sensitivity and specificity. This study introduces a strategy to identify the origins of red seabream using linoleic acid obtained from fatty acid analysis.

Impact of Urea on Monoclonal Antibodies: Multiple Destabilization and Aggregation Effects for Therapeutic Immunoglobulin G Proteins.

We performed nano differential scanning fluorimetry (nanoDSF) measurements of immunoglobulin G (IgG) in urea gradient solutions under thermal unfolding. Our results show that the denaturing effect of urea on individual IgG domains can be monitored via a linear mapping of thermal shift curves to the corresponding urea concentrations. Assignment of IgG domains to each thermal shift curve allows for a reliable differentiation of the underlying mechanisms. Further results show a decisive influence of salt-induced electrostatic screening effects. We are able to explain all findings by preferential binding mechanisms in combination with electrostatic effects. The results of our study shed more light on the complex interaction mechanisms between buffer solutions and complex proteins, which are important for improving the shelf life of protein therapeutic formulation.

Perception of Long-Term Oxygen Therapy for Chronic Lung Diseases May Affect Poor Adherence in Korea.

BACKGROUND: Long-term oxygen therapy (LTOT) improves the survival of patients with hypoxemia due to chronic respiratory diseases. The clinical outcomes of LTOT are strongly associated with patient adherence. To improve the adherence of patients, physicians have focused on the efficacy of LTOT. However, poor adherence may stem from patients' perceptions of LTOT. Herein we evaluated patients' perceptions of LTOT affecting adherence. METHODS: We conducted a cross-sectional survey study using descriptive, open, and closed-ended questionnaire. Patients using oxygen therapy (OT) or requiring it but avoiding OT responded to the questionnaires at three university hospitals. RESULTS: Seventy-nine patients responded to the questionnaires. The number of patients using home and portable OT was 69 (93%) and 37 (46.3%), respectively. Patients with good adherence were 22 (30.1%). Among patients with good adherence, 90.9% used oxygen according to physicians' prescriptions whereas only 37.3% of those with poor adherence followed physicians' prescriptions (p<0.01). The reasons for avoiding using home OT were fear of permanent use (50%), unwanted attention (40%), and lack of symptoms (40%). They avoided portable OT because of unwanted attention (39%), heaviness (31.7%), and lack of symptoms (21.6%). CONCLUSION: Patients on LTOT had the perception of the misunderstanding the effects of OT and of psychosocial barriers to initiate or use LTOT. Considering these findings, health professionals need to provide effective education on the purpose of LTOT to improve patient adherence to OT and provide sufficient support for the management of psychosocial barriers in patients using LTOT.

Biomarker Development for Identifying Mud Loach (Misgurnus mizolepis) Origin Country Using Untargeted Metabolite Profiling.

Mud loach (Misgurnus mizolepis) has long been consumed in Korea. Recently, Chinese mud loaches were replaced with expensive Korean mud loaches, owing to taste and preference. Such issues occur in aquatic food distribution processes, leading to inferior food delivery. Previously, a study was conducted to confirm the origin of mud loaches using genetic analysis. However, untargeted metabolites profiling of mud loaches has not been reported. Untargeted metabolomics provides information on the overall metabolic profiling of a sample, allowing the identification of new metabolites. Here, we analyzed the metabolites of mud loaches of different geographical origins using liquid chromatography (LC)-quadrupole-time-of-flight mass spectrometry (MS). Orthogonal partial least squares discriminant analysis from LC/MS datasets showed a clear distinction between Korean and Chinese mud loaches, and univariate statistical analysis showed significantly different metabolites between them. N-acetylhistidine and anserine were selected as biomarkers for geographical origin discrimination using the receiver operating characteristic curve. N-acetylhistidine and anserine levels were significantly higher in Chinese than in Korean mud loaches. These results indicate that metabolic analysis can be used to discriminate between the geographical origins of mud loaches, curtailing the inadvertent substitution of mud loaches from different regions.

Complete mitochondrial genome of scorpionfish Scorpaena neglecta (Actinopterygii).

Scorpaena neglecta (Temminck and Schlegel, 1843) is a marine fish, in the family Scorpaenidae, order Scorpaeniformes, class Actinopterygii of the phylum Chordata. The first species of Scorpaena with a complete mitochondrial genome is described in the present study. The circular mitochondrial genome of S. neglecta has 17,202 bp with 54.75% A + T content and encodes 37 genes, including 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA), and two ribosomal RNA (rRNA). The phylogenetic tree indicates S. neglecta clustered into one branch and is closely related to other Scorpaenidae species. The mitochondrial genome structure and gene content of S. neglecta will support the study of evolution and phylogenetic relationships among Scorpaenidae species.

Comparison of Extraction Methods and Extraction Optimization in Aqueous Two-Phase System for Ethyl Carbamate Analysis in Model Systems for Maesil Wine.

Ethyl carbamate (EC) is a known carcinogen, and therefore its intake is regulated internationally. The objectives of this study were to compare the EC recovery yields under different liquid-liquid extraction (LLE) conditions and to investigate the optimum conditions of the aqueous two-phase system (ATPS) for EC extraction. Our results showed that for the LLE method, addition of 15% NaCl improved the EC yield by 15%, and dichloromethane as the extraction solvent showed a slightly higher yield (about 5%) than chloroform. However, there was little difference in the yield when mixing was performed using an ultrasonic bath compared to a vortex mixer. Using response surface methodology with central composite design to analyze the ATPS results, optimal extraction was found to occur at 21.5°C for 2.8 h in the sample containing 70% alcohol and 15% phosphate, showing a recovery yield of 75.64%. This information can be applied to alcoholic beverages and other fermented food products to analyze EC with better extraction methods, depending on the types of food.

Complete mitochondrial genome of marine Petrale sole Eopsetta jordani (Pleuronectiformes: Pleuronectidae) flatfish.

Petrale sole Eopsetta jordani (Pleuronectiformes: Pleuronectidae) is a species of flounder, found in the northeastern Pacific Ocean and the Bering Sea of the United States and Canada. The complete mitochondrial DNA (mtDNA) of E. jordani has 16,483 bp with an overall A + T content of 61% and consists of 2 ribosomal RNA (rRNA) genes, 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, and a non-coding control region. It has incomplete stop codon genes in ND2, COII, ATPase6, COIII, ND3, and ND4. Phylogenetic analysis indicated that E. jordani is not monophyletic with cogeneric Eopsetta grigorjewi and is separated from other species in the same family by a large distance. Present study results provide useful data for further research on genetic diversity and evolution of the Eopsetta and the Pleuronectidae.

Characterization of the complete mitochondrial genome of demersal flatfish Eopsetta grigorjewi (Pleuronectiformes: Pleuronectidae) from South Korea.

Eopsetta grigorjewi (Pleuronectiformes: Pleuronectidae) is a demersal flatfish found in South Korea, Japan, Taiwan, China, and the Yellow Sea. E. grigorjewi complete mitochondrion DNA (mtDNA) consists of 16,921 bp and a 54% A + T content. It includes 2 ribosomal RNA (rRNA), 22 transfer RNA (tRNA), 13 protein-coding genes, and 1 non-coding regulatory area. ND2, ND3, ND4, COII, COIII, ATPase6, and CytB all have incomplete stop codon genes. The evolutionary analysis of 13 species from the same family indicated a close relationship. This work will be valuable for future research on molecular evolution and the creation of biomarker databases for determining the originality of E. grigorjewi.

Ethyl Carbamate Formation from Cyanate in Model System of Ethanol-Water Media Using Response Surface Methodology.

Ethyl carbamate (EC) has been identified as a possible human carcinogen belonging to Group 2A. EC is naturally formed during the fermentation and storage of alcoholic drinks and fermented foods. When ingested in large amounts, EC can cause various health problems, such as gastroenteric hemorrhage, vomiting, and cancer. In this study, optimization of EC formation from cyanate was examined using response surface methodology (RSM), a central composite design that includes variables such as alcohol concentration (10, 15, 20, 25, and 30%), pH (2.5, 3.0, 3.5, 4.0, and 4.5), storage temperature (5, 10, 15, 20, and 25°C), and storage duration (2, 4, 6, 8, and 10 days). EC content was determined using gas chromatography with flame ionization detection and the results were optimized using RSM. EC formation from cyanate degradation was found to increase with storage duration and temperature, acidity, and alcohol concentration. Cy-anate degradation was associated with the formation of EC. Approximately 83.1±0.1% of cyanate was degraded to 538±9 µM of EC. However, not all of the cyanate reacted with ethanol during fermentation to form EC. This study aimed to develop the ideal conditions for EC analysis to reduce EC production in alcoholic drinks and fermented foods.

Development and validation of multiplex PCR assay for differentiating tunas and billfishes.

Commercially available tunas and billfishes are generally processed as steaks, making it difficult to visually distinguish between the two. We developed and validated species-specific primers to prevent the adulteration of tunas by billfishes. Tunas and billfishes primers were designed on the cytochrome oxidase subunit I. Multiplex PCR bands obtained were 579 bp, 291 bp and 114 bp for tunas, billfishes and internal control. Sensitivity was determined to be 5 ng for tunas and billfishes. A total of 50 samples were monitored: 49 for tunas and 1 for billfish. As a result of the monitoring, the fake tunas did not show due to the agreement between product name and the raw material of the wrapping paper. Our results indicate that the species-specific primers developed in this study are suitable for differentiating tunas and billfishes. The newly developed multiplex PCR assay is a time and cost effective technique for determining the authenticity of tunas and billfishes.

Complete mitochondrial genome of sea peach Halocynthia aurantium (stolidobranchia: Pyuridae) from Korea.

Halocynthia aurantium (Stolidobranchia: Pyuridae) is a species of tunicate of commercial value that is commonly found in the northern Pacific Ocean and in the Bering Sea. Here, we determined the complete mitogenome of sea peach H. aurantium using 150 PE high-throughput sequencing. The assembled mitogenome is 14,979 bp in length (overall A + T contents 56.2%), and contains 13 protein-coding genes, 21 transfer RNAs, two ribosomal RNAs. Phylogenetic analysis of the mitogenome sequence of H. aurantium fully resolved it in a clade with H. roretzi. These data and results will be useful for future studies on the evolution of the Halocynthia and the Pyuridae.

The complete mitochondrial genome of pitted stingray Bathytoshia brevicaudata (Myliobatiformes: Dasyatoidea).

The complete mitochondrial genome of pitted stingray, Bathytoshia brevicaudata (Myliobatiformes: Dasyatoidea) was investigated by next-generation sequencing. The analyzed mitochondrial genome was 17,640 nucleotides in length and had 59.2% for AT contents. This genome contains 2 ribosomal RNA genes, 13 protein-coding genes, 22 transfer RNA genes. and 1 putative control region. Five protein-coding genes (ATPase6, COII, ND2, ND3, ND4) including incomplete stop codons and four tRNAs have atypical codons. The phylogenetic inference including 13 species of the same family revealed a close relationship with Pteroplatytrygon violacea. This is the first mitochondrial genome report from genus Bathytoshia.

Signal detection of human papillomavirus vaccines using the Korea Adverse Events Reporting System database, between 2005 and 2016.

Background Adverse events (AEs) not listed on drug labels have recently been reported in young girls vaccinated against HPV, but signal detection related to the human papillomavirus (HPV) vaccine has never been conducted in South Korea using the Korea Adverse Event Reporting System database of Korea Institute of Drug Safety & Risk Management at Ministry of Food and Drug Safety. Objective To analyze signals associated with HPV vaccines using the Korean spontaneous AEs reporting system and data-mining methods and compare the results to current vaccine label information in South Korea and the United States of America, United Kingdom, European Union, and Japan to detect signals not currently listed on the labels. Setting We evaluated the Korea Institute of Drug Safety & Risk Management database from January 2005 to December 2016. After pre-screening the data, the adjusted total numbers of HPV-related AE reports and AEs were 2566 and 4748 and those of all other vaccine-related AE reports and AEs were 21,878 and 120,688, respectively. Methods Three data mining algorithms (proportional reporting ratio, reporting odds ratio and information component) were used to assess AEs. A signal was defined when the criteria for all three indicators were satisfied. The detected signals were compared to the label information of HPV vaccines from South Korea, the United States of America, United Kingdom, European Union, and Japan. Main outcome measure Signals of AE after HPV vaccination, which met all three data mining indices. Results In this study, we found a total 97 signals of AE after HPV vaccination. Of these, 78 AEs were already present on the HPV vaccine labels of South Korea and the following 19 AEs were not listed: neuralgia, tremor, neuritis, depersonalization, axillary pain, personality disorder, increased salivation, peptic ulcer, circulatory failure, hypotension, peripheral ischemia, cerebral hemorrhage, micturition disorder, facial edema, ovarian cyst, weight increase, pain anxiety, oral edema, and back pain. Moreover, AE information on the current HPV vaccine labels of South Korea, the United States of America, United Kingdom, European Union, and Japan was inconsistent. When comparing the 19 AE signals that were not listed on the drug label in South Korea with the labels from the other countries, neuritis, axillary pain, cerebral hemorrhage, facial edema, pain anxiety, and back pain appreared on the U.S. Food and Drug Administration HPV vaccine labels but not on the United Kingdom labels, and hypotension was listed only on labels in the European Union and Japan. Conclusions South Korea should develop a system for proactively updating HPV labels. These results also suggest potential research directions such as vaccination label expansion, pharmacovigilance studies, and identification of causality in AEs associated with HPV vaccination.

Evolutionary Comparison of the Chloroplast Genome in the Woody Sonchus Alliance (Asteraceae) on the Canary Islands.

The woody Sonchus alliance consists primarily of woody species of the genus Sonchus (subgenus Dendrosonchus; family Asteraceae). Most members of the alliance are endemic to the oceanic archipelagos in the phytogeographic region of Macaronesia. They display extensive morphological, ecological, and anatomical diversity, likely caused by the diverse habitats on islands and rapid adaptive radiation. As a premier example of adaptive radiation and insular woodiness of species endemic to oceanic islands, the alliance has been the subject of intensive evolutionary studies. While phylogenetic studies suggested that it is monophyletic and its major lineages radiated rapidly early in the evolutionary history of this group, genetic mechanisms of speciation and genomic evolution within the alliance remain to be investigated. We first attempted to address chloroplast (cp) genome evolution by conducting comparative genomic analysis of three representative endemic species (Sonchus acaulis, Sonchus canariensis, and Sonchus webbii) from the Canary Islands. Despite extensive morphological, anatomical, and ecological differences among them, their cp genomes were highly conserved in gene order and content, ranging from 152,071 to 152,194 bp in total length. The number of repeat variations and six highly variable regions were identified as valuable molecular markers. Phylogenetic analysis of 32 species in the family Asteraceae revealed the phylogenetic position of the woody Sonchus alliance within the tribe Cichorieae and the sister relationship between the weedy Sonchus oleraceus and the alliance.

Complete chloroplast genome of Ulleung Island endemic pokeweed, Phytolacca insularis (Phytolaccaceae), in Korea.

The first complete chloroplast genome sequences of Korean endemic pokeweed in Ulleung Island, Phytolacca insularis, were reported in this study. The P. insularis plastome was 156,419 bp long, with the large single copy (LSC) region of 86,106 bp, the small single copy (SSC) region of 18,335 bp, and two inverted repeat (IR) regions of 25,989 bp. The plastome contained 132 genes, including 84 protein-coding, eight ribosomal RNA, and 39 transfer RNA genes. The overall GC content was 36.8%. Phylogenetic analysis of 13 representative plastomes within the order Caryophyllales suggests that P. insularis is closely related to the species in family Aizoaceae.

The complete mitochondrial genome of bobo croaker Pseudotolithus elongatus (Perciformes: Sciaenidae).

The complete mitochondrial genome of Pseudotolithus elongatus (Perciformes: Sciaenidae) is determined based on NGS technology. The assembled mitogenome is a 16,497 bp in length containing a typical set of the 13 protein-coding genes, 22 tRNAs, 2 rRNA genes, and the 1 putative control region. The overall base composition is A (27.8%), T (25.3%), G (16.1%), and C (30.8%) with an A-T content of 53.1%. The phylogenetic analysis of 36 mitogenomes from the GenBank indicated that P. elongatus is closely related to the Aplodinotus grunniens. This mitogenome information of the P. elongatus would be useful to understand evolutionary and phylogenetic analysis of the family Sciaenidae fishes.

Chloroplast genome of critically endangered Cotoneaster wilsonii (Rosaceae) endemic to Ulleung Island, Korea.

Cotoneaster wilsonii Nakai is an endangered species endemic to Ulleung Island, Korea. Here we reported the first complete chloroplast gnome sequences of C. wilsonii, which is 159,999 bp in total length with the large single copy (LSC) region of 87,868 bp, the small single copy (SSC) region of 19,335 bp, and two inverted repeat (IR) regions of 26,399 bp. The plastome contains 131 genes, including 84 protein-coding, eight ribosomal RNA, and 37 transfer RNA genes. The overall GC content is 42.6% and those in the LSC, SSC, and IR regions are 34.2, 30.3, and 42.6%, respectively. Phylogenetic analysis of 21 representative plastomes within the family Rosaceae suggests strongly the monophyly of Cotoneaster and C. wilsonii being sister to the clade of Cotoneaster franchetii and Cotoneaster horizontalis.