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A novel solid-phase microextraction Arrow was used to separate volatile organic compounds from soy sauce, and the results were verified by using gas chromatography with mass spectrometry. Solid-phase microextraction Arrow was optimized in terms of three extraction conditions: type of fiber used (polydimethylsiloxane, polyacrylate, carbon wide range/polydimethylsiloxane, and divinylbenzene/polydimethylsiloxane), extraction temperature (40, 50, and 60°C), and extraction time (10, 30, and 60 min). The optimal solid-phase microextraction Arrow conditions were as follows: type of fiber = polyacrylate, extraction time = 60 min, and extraction temperature = 50°C. Under the optimized conditions, the solid-phase microextraction Arrow was compared with conventional solid-phase microextraction to determine extraction yields. The solid-phase microextraction Arrow yielded 6-42-fold higher levels than in solid-phase microextraction for all 21 volatile organic compounds detected in soy sauce due to the larger sorption phase volume. The findings of this study can provide practical guidelines for solid-phase microextraction Arrow applications in food matrixes by providing analytical methods for volatile organic compounds.

Pesticides are used to increase crop yields and preserve quality by protecting crops against pests; however, their overuse can adversely affect human health and the environment. Herein, we report the development of a multi-pesticide screening method using optimized QuEChERS coupled with liquid chromatography/quadrupole time-of-flight (QTOF) mass spectrometry for the analysis of 13 pesticides in wheat flour. Mass accuracies with errors of less than 2.4 ppm were obtained for all analysed pesticides, and the method provided satisfactory recovery and linearity. Repeatabilities of 0.3-12.7% and reproducibilities of 2.5-15.2% were observed in full-scan TOF mode. The performance of the developed full-scan TOF method was compared to that obtained in high-resolution multiple reaction monitoring (MRM-HR) mode. The limits of quantification for the full-scan TOF and MRM-HR modes ranged from 2 to 10, and 3 to 9 μg kg

Omija (Schisandra chinesis Baillon) is a cluster of berries, mainly cultivated in East Asian countries. The objective of this study was to conduct an instrumental volatile flavor analysis and descriptive analysis of omija samples using headspace stir-bar sorptive extraction gas chromatography-mass spectrometry. Three omija fruits were included and pre-treated using three different methods: frozen omija (FO), frozen-blended omija (FBO), and freeze-dried omija (FDO). A total of 28 volatiles were identified, and significant differences in concentrations found among omija samples were noted, especially for previously identified aroma-active compounds such as α-pinene, α-terpinene, and (E)-β-ocimene (p .05). In terms of sensory perception, significant differences were observed in three sensory attributes that included, ginger, pine needle, and wet grassy aromatics among the samples (p 0.05). While similarities and dissimilarities were observed among the three samples in the instrumental flavor analysis results, a principal component analysis revealed that FBO and FDO shared similar flavor characteristics while FO had distinctive flavor characteristics.

A new solid phase microextraction (SPME)-Arrow method was evaluated for the analysis of volatile compounds in kanari-aekjeot, a Korean traditional salt–fermented sand lance sauce, and compared it to the standard headspace–SPME method. Factors observed to affect the extraction, including the fiber used, extraction temperature, extraction time, and NaCl concentration were carefully optimized. The Carboxen/Polydimethylsiloxane fiber exhibited the highest extraction efficiency for both analytical methods and was selected for further optimization of the extraction. The major volatile compounds extracted using both methods were 3-methyl butanoic acid, butanoic acid, acetic acid, 2,6-dimethylpyrazine, and benzaldehyde. The relative concentration (mg/L) of 3-methyl butanoic acid was 1.4-fold higher when using SPME. However, the SPME-Arrow method was more effective at extracting aromatic compounds including alcohol, aldehydes, and pyrazine. In particular, 3-methyl-1-butanol, 2-furanmethanol, and phenylethyl alcohol could only be detected using SPME-Arrow due to its larger sorbent volume. Thus, SPME-Arrow was evaluated as being more suitable for the extraction of pyrazines in sand lance fish sauce and might be useful for determining a broader range of volatile compounds in complex fermented foods.

A rapid analytical method was developed for the determination of 4-methylimidazole from red ginseng products containing caramel colors by using dispersive liquid-liquid microextraction with in situ derivatization followed by gas chromatography with mass spectrometry. Chloroform and acetonitrile were selected as the extraction and dispersive solvents, and based on the extraction efficiency, their optimum volumes were 200 and 100 μL, respectively. The optimum volumes of the derivatizing agent (isobutyl chloroformate) and catalyst (pyridine), pH, and concentration of NaCl in the sample solution were determined to be 25 and 100 μL, pH 7.6, and 0% w/v, respectively. Validation of the optimized method showed good linearity (R2 > 0.999), accuracy (≥89.86%), intra- (≤6.70%) and interday (≤4.17%) repeatability, limit of detection (0.96 μg/L), and limit of quantification (5.79 μg/L). The validated method was applied to quantify 4-methylimidazole in red ginseng juices and concentrates, 4-methylimidazole was only found in red ginseng juices containing caramel colorant (42.91-2863.4 μg/L) and detected in red ginseng concentrates containing >1% caramel colorant.

Makgeolli is a traditional Korean rice wine reported to have anticancer, anti-inflammatory, and antioxidant effects. We developed an approach involving solvent extraction coupled with gas chromatography-mass spectrometry to determine four bioactive compounds, farnesol (FOH), squalene (SQ), and newly identified 4-vinyl guaiacol (4-VG) and 2,4-di-tert-butylphenol (DTBP), in makgeolli. The method was validated with the linearity, limit of detection, limit of quantification, intra- and inter-day precision, and accuracy. The validated method was then applied to several makgeolli, beer, and wine samples. 4-VG and DTBP were identified in all beverages, but FOH and SQ were only identified in makgeolli.

Schisandra chinensis (Turcz.) Baill., which is known as omija in South Korea, is mainly cultivated in East Asia. The present study aimed to investigate the chemical composition of essential oil from the omija (OMEO) fruit obtained by supercritical fluid extraction using CO2 and to confirm the antioxidant and anti-inflammatory activity of OMEO using HaCaT human keratinocyte and RAW 264.7 murine macrophages. As a result of the chemical composition analysis of OMEO using gas chromatography-mass spectrometry, a total of 41 compounds were identified. The detailed analysis results are sesquiterpenoids (16), monoterpenoids (14), ketones (4), alcohols (3), aldehydes (2), acids (1), and aromatic hydrocarbons (1). OMEO significantly reduced the increased ROS levels in HaCaT keratinocytes induced by UV-B irradiation (p &lt, 0.05). It was confirmed that 5 compounds (α-pinene, camphene, β-myrcene, 2-nonanone, and nerolidol) present in OMEO exhibited inhibitory activity on ROS production. Furthermore, OMEO showed excellent anti-inflammatory activity in RAW 264.7 macrophages induced by lipopolysaccharide. OMEO effectively inhibited NO production (p &lt, 0.05) by suppressing the expression of the iNOS protein. Finally, OMEO was investigated for exhibition of anti-inflammatory activity by inhibiting the activation of NF-κB pathway. Taken together, OMEO could be used as a functional food ingredient with excellent antioxidant and anti-inflammatory activity.

A simple and rapid dispersive liquid-liquid microextraction method coupled with gas chromatography and mass spectrometry was applied for the determination of glyoxal as quinoxaline, methylglyoxal as 2-methylquinoxaline, and diacetyl as 2,3-dimethylquinoxaline in red ginseng products. The performance of the proposed method was evaluated under optimum extraction conditions (extraction solvent: chloroform 100 μL, disperser solvent: methanol 200 μL, derivatizing agent concentration: 5 g/L, reaction time: 1 h, and no addition of salt). The limit of detection and limit of quantitation were 1.30 and 4.33 μg/L for glyoxal, 1.86 and 6.20 μg/L for methylglyoxal, and 1.45 and 4.82 μg/L for diacetyl. The intra- and interday relative standard deviations were

We evaluated organosulphur compounds in Allium vegetables, including garlic, elephant garlic and onion, using high-performance liquid chromatography. Among organosulphur compounds, elephant garlic had considerable γ-glutamyl peptides, and garlic had the highest alliin content. Onion had low level of organosulphur compounds than did elephant garlic and garlic. In addition, antioxidant capacities were evaluated by oxygen radical absorbance capacity (ORAC) values and 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging assay. The results showed that garlic had the highest antioxidant capacity, followed by elephant garlic and onion. Furthermore, a positive correlation was observed between antioxidant activities and organosulphur compounds (R > 0.77). Therefore, our results indicate that there was a close relationship between antioxidant capacity and organosulphur compounds in Allium vegetables.

Summary Aims In spite of the reported efficacy and safety of antimuscarinics in men with OAB (overactive bladder) and BPO (benign prostatic obstruction), many patients do not persist with the treatment. We aimed to evaluate persistence and the reasons for the discontinuation of solifenacin add-on therapy in men with residual symptoms of OAB after tamsulosin monotherapy for BPO in a real clinical environment. Methods Men aged ≥ 45 years with IPSS ≥ 12 and symptoms of OAB (OAB-V8 ≥ 8, micturition ≥ 8/24 h, urgency ≥ 2/24 h) were prescribed tamsulosin 0.2 mg. After 4 weeks, men who had residual symptoms of OAB (OAB-V8 ≥ 8, micturition ≥ 8/24 h, urgency ≥ 1/24 h) and reported that they were ‘dissatisfied’ or ‘a little satisfied’ with the therapy were enrolled and prescribed solifenacin 5 mg in combination with tamsulosin. After 52 weeks, persistence and the reasons for the discontinuation of solifenacin were evaluated. Factors related to persistence were analysed. Results Of the 305 men who had been treated with tamsulosin, 176 were prescribed solifenacin. After 52 weeks, 44 (25%) remained on solifenacin therapy. Of the 132 who discontinued solifenacin, 85 were evaluated on the reason for discontinuation. The three most common reasons for discontinuation were adverse events (AEs) (35%), lack of efficacy (33%), and improvement in symptoms (16%). The aggravation of voiding symptoms was the most common AE leading to discontinuation. Retention was observed in 11 men. None of the demographical or clinical characteristics were significantly related to persistence. Conclusions Only 25% men with OAB and BPO remained on antimuscarinic add-on therapy after 1 year, mostly because of AEs and lack of efficacy. Realistic data should be added to what is already known about antimuscarinic treatment in men by including patients who were excluded or who dropped out of well-designed clinical trials.

An analytical method involving QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation, followed by LC-MS/MS and GC-MS/MS was developed and validated for the determination of 60 pesticides in eggs. Recoveries of 70-120% were achieved for selected pesticides and relative standard deviations20% were obtained for most analytes at three concentrations. The limit of quantification was10 µg kg

Summary Aim: Standardised traditional outcome measures may fail to address factors that are important to patients and address irrelevant factors. Aim of this study was to assess patient-reported goals and goal achievement (GA) in the antimuscarinic treatment for overactive bladder (OAB) patients. Methods: Men and women aged ≥ 18 years with OAB symptoms were eligible for the study. Treatment began with a dose of 10 mg oxybutynin, to be increased if necessary to 30 mg. Before treatment, each patient’s primary treatment goal was identified. After 12-week treatment, patients reported GA using a Likert scale from 0 (no achievement) to 5 (complete achievement). Successful achievement was defined as a score of 4 or 5. Traditional outcome measures including voiding diaries, the OAB questionnaire short form, patient perception of bladder condition, and treatment benefit and satisfaction were assessed. Baseline characteristics affecting GA and the correlation between GA and traditional outcome measures were evaluated. Results: A total of 303 goals were identified from 303 patients (51 men, 252 women). Of those, 72.3% addressed symptom relief and frequency as the most common target symptom. Other goals addressed were improving quality of life (13.5%) and eliminating coping behaviours (14.2%). After treatment, 42% had a successful GA with a median score of 3 (interquartile range; 2–4). Age had a negative effect on GA. Goal achievement was the outcome measure most correlated with treatment benefit and satisfaction. Discussion and Conclusions: Goal achievement can be a valuable outcome measure in OAB patients, addressing individual treatment goals and reflecting treatment benefit and patient satisfaction.

Summary Aims: Efficacy of antimuscarinic therapy for overactive bladder (OAB) has been demonstrated; however, the durability of its effects is unknown. The study was conducted to evaluate symptom change and retreatment rate after discontinuation of antimuscarinic therapy. Also, we tried to find risk factors for retreatment. Methods: This was a prospective, randomised, open-label, multicentre trial at four university hospitals. Women who had OAB symptoms for ≥ 6 months and who showed successful response to 1 month of Tolterodine 4 mg medication were randomly assigned to one of three groups: (A) discontinue medication, (B) 2-month additional medication and (C) 5-month additional medication. After completion of the 1-, 3- or 6-month treatment, patients stopped the medication and were followed up for additional 3 months to assess symptom relapse and retreatment rates. Risk factors for retreatment were evaluated. Results: Of a total of 558 patients who took the study medication, 173 were randomised and 108 (A: 40, B: 40, C: 28) were included in the analysis. At the end of the treatment, the mean micturition frequency was decreased to 8.3/24 h from 11.7/24 h, and the mean urgency episode was decreased to 2.2/24 h from 8.0/24 h. Three months after discontinuation, the micturition frequency and the urgency episode were increased to 9.1/24 and 4.4/24 h respectively. Sixty five per cent of patients requested retreatment, and 62% experienced symptom relapse. Baseline health-related quality of life was the only independent risk factor for retreatment. Discussion and conclusion: Discontinuation of antimuscarinic therapy resulted in high symptom relapse and retreatment rates regardless of treatment duration. The results provide new information on the durability of the efficacy of antimuscarinics, and may improve treatment efficacy by promoting the medication persistence of antimuscarinics in OAB patients.

The aim of the current study is to compare the prevalence, severity and location of cerebral white matter hyperintensities (WMH) between patients with panic disorder (PD) and healthy control subjects. Patients with PD (n = 24) and matched healthy control subjects (n = 24) were scanned using a 3.0 Tesla whole-body magnetic resonance scanner. Axial T2-weighted and fluid-attenuated inversion recovery images were acquired and evaluated for the prevalence, severity and location of WMH using the modified composite scale of Fazekas and Coffey and coded separately for deep and periventricular WMH. Logistic regression analyses were used to assess the association between WMH and the diagnosis of PD. A greater severity of total WMH was associated with a diagnosis of PD in a dose-dependent pattern (odds ratio [OR] = 8.8, P = 0.005 for mild WMH; OR = 27.7, P = 0.007 for moderate to severe WMH). Deep WMH, where most group differences originated, were predominantly located in the frontal region of the brain (n = 16 in PD, n = 1 in control). The current report is the first study to report an increased prevalence of WMH in patients with PD.

We report the drastic enhancement of Shubnikov–de Haas (SdH) oscillations observed in a GaN/AlGaN heterostructure by microwave modulation. The dependence of the SdH pattern on microwave power and temperature are investigated. The underlying mechanism is attributed to the effect of carrier heating. This technique helps study the transport properties of two-dimensional electrons in a GaN/AlGaN heterostructure. In addition, this method has the advantage of keeping the carrier concentration fixed and not requiring expensive high-energy laser facilities compared with carrier-modulated SdH measurements.

We studied the insulator-quantum Hall conductor transition which separates the low-field insulator from the quantum Hall state of the filling factor $\nu=4$ on a gated two-dimensional GaAs electron system containing self-assembled InAs quantum dots. To enter the $\nu=4$ quantum Hall state directly from the low-field insulator, the two-dimensional system undergoes a crossover from the low-field localization to Landau quantization. The crossover, in fact, covers a wide range with respect to the magnetic field rather than only a small region near the critical point of the insulator-quantum Hall conductor transition., Comment: Our experimental results are inconsistent with Huckestein's argument [PRL 84, 3141 (2000)]

Objectives – The aim of this study was to investigate gray matter volume changes in narcolepsy. Materials and methods – An optimized voxel-based morphometry was conducted for 17 young adults with a sole diagnosis of human leukocyte antigen DQB1 0602 positive narcolepsy with cataplexy (26.6 ± 5.2 years old) and 17 comparison subjects (24.6 ± 4.9 years old) using 3 Tesla scanner. Gray matter volumes in the bilateral hypothalamic voxel of interests (VOI) were also calculated. Results – Compared with the comparison subjects, narcoleptic patients had gray matter volume decrease in the right hypothalamus and other regions including subcortical, prefrontal, limbic and occipital areas. Narcoleptic patients also had lower gray matter volume on predefined VOI at the bilateral hypothalamus, which correlated with the Ullanlinna Narcolepsy Scale score. Conclusions – Current findings suggest that narcoleptic patients have structural abnormalities in hypothalamus, which might be related to the clinical manifestation of narcolepsy with cataplexy.