Yiseul Kim

Clinical and angiographic follow-up of spontaneous isolated superior mesenteric artery dissection.

OBJECTIVES To observe the clinical features and angiographic findings in patients with a spontaneous isolated superior mesenteric artery dissection (SISMAD) and to identify any correlation between them. METHODS From a single institution, 32 patients (22 symptomatic patients at presentation; mean age 54years; men 97%) with SISMAD were retrospectively reviewed. All patients were available for clinical follow-up after treatment (conservative, n=28, 88%, open or endovascular superior mesenteric artery (SMA) reconstruction, n=4, 12%), and follow-up CT scans were available in 28 patients (mean 22months, range 1-80months). RESULTS We found a positive correlation between pain severity and dissection length (p=0.03, rho=0.50, Spearmans partial correlation analysis). After conservative treatment, only one patient (3%) required bowel resection, and there was no difference in outcome between patients who were treated with anticoagulation or anti-platelet therapy and those who were not (p=1.00, Fishers exact test). No patients had progression of their lesion on the follow-up CT angiography. CONCLUSIONS In SISMAD patients, dissection length is positively associated with more severe clinical symptoms. After conservative treatment, we observed a benign clinical course and no CT progression of the dissection, even without anticoagulation or anti-platelet therapy. Based on our observation, patients with SISMAD can be treated conservatively without anticoagulation therapy.

The TRPA1 agonist, methyl syringate suppresses food intake and gastric emptying.

Transient receptor potential channel ankryn 1 (TRPA1) expressed in the gastrointestinal tract is associated with gastric motility, gastric emptying, and food intake. In this study, we investigated the effects of methyl syringate, a specific and selective TRPA1 agonist, on food intake, gastric emptying, and gut hormone levels in imprinting control region (ICR) mice. The administration of methyl syringate suppressed cumulative food intake and gastric emptying. In addition, treatment with ruthenium red (RR), a general cation channel blocker, and HC-030031, a selective TRPA1 antagonist, inhibited methyl syringate-induced reduction of food intake and delayed gastric emptying in ICR mice. Methyl syringate also increased plasma peptide YY (PYY) levels, but not glucagon-like peptide-1 (GLP-1) levels. The elevation in PYY was blocked by treatment with RR and HC-030031. The present findings indicate that methyl syringate regulates food intake and gastric emptying through a TRPA1-mediated pathway and, by extension, can contribute to weight suppression.

Umami-bitter interactions: the suppression of bitterness by umami peptides via human bitter taste receptor.

Taste-taste interactions often showed in human psychophysical studies. Considering that each tastant in foodstuffs individually stimulates its responsible gustatory systems to elicit relevant taste modalities, taste-taste interaction should be performed in taste receptor cell-based assay. While umami substances have been proposed to suppress the bitterness of various chemicals in human sensory evaluation, the bitter-umami interaction has not been explored in bitter taste receptors, TAS2Rs. We investigated umami-bitter taste interactions by presenting umami peptides with bitter substance (salicin) on Ca(2+)-flux signaling assay using hTAS2R16-expressing cells. Five representative umami peptides (Glu-Asp, Glu-Glu, Glu-Ser, Asp-Glu-Ser, and Glu-Gly-Ser) derived from soybean markedly attenuated the salicin-induced intracellular calcium influx in a time-dependent manner, respectively, while Gly-Gly, a tasteless peptide did not. The efficacies of Glu-Glu suppressing salicin-induced activation of hTAS2R16 were higher than that of probenecid, a specific antagonist of hTAS2R16. According to Ca(2+)-flux signaling assay using the mixtures of salicin and umami peptides, all five umami peptides suppressed salicin-induced intracellular calcium influx in a noncompetitive manner. These results may provide evidence that umami peptides suppress bitter taste via bitter taste receptor(s). This is the first report which defines the interaction between bitter and umami taste in taste receptor level.

Proper Selection of Patients for Percutaneous Embolo-Sclerotherapy in Patients with Congenital Vascular Malformations (CVMs)

For the treatment of congenital vascular malformation (CVM), conservative, endovascular and/or surgical treatment have been sporadically attempted according to the type, location and clinical manifestations of the vascular lesions. At current practice, with no established treatment guidelines for CVM patients, there is much room for ineffective interventions and occurrence of complications related with the treatment. Therefore, it is important to select proper candidates for the endovascular or surgical treatment in CVM patients to avoid ineffective treatment and its complications and to obtain better treatment results. We describe the basic considerations before the selection of candidates for percutaneous embolo-sclerotherapy in patients with CVM based on our own experiences at a specialised CVM clinic.

Five hTRPA1 Agonists Found in Indigenous Korean Mint, Agastache rugosa.

Transient receptor potential ankyrin1 (TRPA1) and transient receptor potential vanilloid 1 (TRPV1) are members of the TRP superfamily of structurally related, nonselective cation channels and mediators of several signaling pathways. Previously, we identified methyl syringate as an hTRPA1 agonist with efficacy against gastric emptying. The aim of this study was to find hTRPA1 and/or hTRPV1 activators in Agastache rugosa (Fisch. et Meyer) O. Kuntze (A.rugosa), commonly known as Korean mint to improve hTRPA1-related phenomena. An extract of the stem and leaves of A.rugosa (Labiatae) selectively activated hTRPA1 and hTRPV1. We next investigated the effects of commercially available compounds found in A.rugosa (acacetin, 4-allylanisole, p-anisaldehyde, apigenin 7-glucoside, L-carveol, β-caryophyllene, trans-p-methoxycinnamaldehyde, methyl eugenol, pachypodol, and rosmarinic acid) on cultured hTRPA1- and hTRPV1-expressing cells. Of the ten compounds, L-carveol, trans-p-methoxycinnamaldehyde, methyl eugenol, 4-allylanisole, and p-anisaldehyde selectively activated hTRPA1, with EC50 values of 189.1±26.8, 29.8±14.9, 160.2±21.9, 1535±315.7, and 546.5±73.0 μM, respectively. The activities of these compounds were effectively inhibited by the hTRPA1 antagonists, ruthenium red and HC-030031. Although the five active compounds showed weaker calcium responses than allyl isothiocyanate (EC50=7.2±1.4 μM), our results suggest that these compounds from the stem and leaves of A.rugosa are specific and selective agonists of hTRPA1.

Modulation of Sweet Taste by Umami Compounds via Sweet Taste Receptor Subunit hT1R2

Although the five basic taste qualities—sweet, sour, bitter, salty and umami—can be recognized by the respective gustatory system, interactions between these taste qualities are often experienced when food is consumed. Specifically, the umami taste has been investigated in terms of whether it enhances or reduces the other taste modalities. These studies, however, are based on individual perception and not on a molecular level. In this study we investigated umami-sweet taste interactions using umami compounds including monosodium glutamate (MSG), 5’-mononucleotides and glutamyl-dipeptides, glutamate-glutamate (Glu-Glu) and glutamate-aspartic acid (Glu-Asp), in human sweet taste receptor hT1R2/hT1R3-expressing cells. The sensitivity of sucrose to hT1R2/hT1R3 was significantly attenuated by MSG and umami active peptides but not by umami active nucleotides. Inhibition of sweet receptor activation by MSG and glutamyl peptides is obvious when sweet receptors are activated by sweeteners that target the extracellular domain (ECD) of T1R2, such as sucrose and acesulfame K, but not by cyclamate, which interact with the T1R3 transmembrane domain (TMD). Application of umami compounds with lactisole, inhibitory drugs that target T1R3, exerted a more severe inhibitory effect. The inhibition was also observed with F778A sweet receptor mutant, which have the defect in function of T1R3 TMD. These results suggest that umami peptides affect sweet taste receptors and this interaction prevents sweet receptor agonists from binding to the T1R2 ECD in an allosteric manner, not to the T1R3. This is the first report to define the interaction between umami and sweet taste receptors.

Identification of a key umami-active fraction in modernized Korean soy sauce and the impact thereof on bitter-masking

Food protein hydrolysates created by natural fermentation have been used for centuries as food flavorings. The aim of this study was to define the key umami-active fraction of modernized Korean soy sauce (mJGN) and the impact thereof on bitter-masking of human sensory and bitter-taste receptor-expressing cells. We found strong correlations between taste profiles of mJGN and a contained fraction (F05). The latter contained compounds of less than 500Da, and elicits a distinct umami taste. Both free amino acids and Glu-enriched oligopeptides are suggested to be crucial in terms of the effects of F05 on taste. F05 not only reduced human-perceived bitterness, but also effectively suppressed the intracellular Ca2+ response induced by caffeine in the hTAS2R43 and hTAS2R46 human bitter-taste receptor-expressing cells. This suggests that F05, a key umami-active fraction of mJGN, contains components that at least partially modulate human bitter-taste receptor action, improving food flavor.

Correction: A Comparison of Microbial Water Quality and Diversity for Ballast and Tropical Harbor Waters.

[This corrects the article DOI: 10.1371/journal.pone.0143123.].

Unrecognized myocardial infarction detected on cardiac magnetic resonance imaging: Association with coronary artery calcium score and cardiovascular risk prediction scores in asymptomatic Asian cohort

Background To investigate the association between unrecognized myocardial infarction (UMI) assessed with cardiac magnetic resonance (CMR) and coronary artery calcium (CAC) and cardiovascular risk prediction scores in asymptomatic Asian subjects. Materials and methods Total 872 asymptomatic subjects without prior cardiovascular event (male:female, 817:55; age, 53.88 ± 5.91) who underwent both CMR and CAC scoring CT were included. UMI were accessed and framingham risk score (FRS) and ASCVD (atherosclerotic cardiovascular disease) risk score by ACC/AHA were calculated. Results Late gadolinium enhancement indicating UMI was noted in 23 of 872 subjects (2.64%), but only three of them showed ECG abnormality (13.04%). Subjects with UMI showed higher CAC scores, FRS, and ASCVD scores than those without UMI (p < .001, p = .011 and p = .024, respectively). The prevalence of UMI differed significantly according to the CAC scores as follows: 1% in CAC = 0 (4/403), 1% in 1 ≤ CAC <100 (2/293), 6.1% in 100 ≤ CAC < 400 (7/114) and 14.5% in CAC ≥ 400 (9/62), respectively (p < .001). Receiver operating characteristics (ROC) analysis by using CAC score demonstrated an area under the curve (AUC) of 0.816 (95% confidence interval (CI), 0.780–0.848; p < .0001) for predicting UMI, which is superior to FRS [AUC, 0.712; 95% CI, 0.671–0.751; p = .009] and ASCVD risk score [AUC, 0.689; 95% CI, 0.648–0.729; p = .036]. Conclusion The prevalence of UMI increases with increasing burden of CAC and FRS. CAC score is a good discriminator for UMI, superior to FRS and ASCVD score, in asymptomatic population.

Relationship between cardiovascular risk factors and myocardial strain values of both ventricles in asymptomatic Asian subjects: measurement using cardiovascular magnetic resonance tissue tracking

The purpose of this study was to evaluate the association between myocardial deformation parameters and cardiovascular risk factors in asymptomatic Asian subjects and to provide reproducibility for deformation parameters of both ventricles using cardiovascular magnetic resonance (CMR) tissue tracking (TT). We enrolled 129 asymptomatic healthy adults who underwent CMR and assessed the cardiovascular risk factors in all individuals. All subjects had normal left ventricular systolic function. Commercial software was used to derive myocardial deformation parameters of both ventricles from short-axis cine images and long-axis cine images with two-, three-, and four-chamber views. Linear regression analysis was performed for evaluation of the association with all strain parameters for each age and systolic blood pressure. Intra class correlation was also calculated in CMR-TT to determine interobserver variability. In all 129 patients, the strain values for the left ventricle (LV) were 48.90 ± 9.05 for radial strain (RS, %), − 22.30 ± 2.33 for circumferential strain (CS, %), and − 19.76 ± 2.22 for longitudinal strain (LS, %). The strain values for the right ventricle (RV) were 18.63 ± 6.52 for RS, − 10.60 ± 3.33 for CS, and − 25.06 ± 3.01 for LS. In all 129 patients (male, n = 105), all strain parameters of LV and RV was significantly different among males and females (all p values < 0.05). The LV strain parameters were significantly associated with age by univariate linear regression analysis: RS, beta = 0.219, p = 0.002; CS, beta = − 0.668, p = 0.014 (except for LS, beta = − 0.104, p = 0.720). With regard to hypertension, diabetes mellitus and dyslipidemia, the values of all strain parameters in both ventricles were not significantly different between individuals with or without risk factors. Inter-observer agreement for three strain variables of LV and RV was 0.915 and 0.715 by iota index, and intra-observer agreement of LV and RV was 0.955 and 0.959 by iota index. The strain parameters by CMR-TT showed an association with age and significant difference in gender, on the other hands, not significantly different between with or without of the other conventional cardiovascular risk factors. The reproducibility of three LV strain parameters was higher than that of the respective RV strain parameters.