Deep Learning-Based Diagnostic System for Velopharyngeal Insufficiency Based on Videofluoroscopy in Patients With Repaired Cleft Palates.

Velopharyngeal insufficiency (VPI), which is the incomplete closure of the velopharyngeal valve during speech, is a typical poor outcome that should be evaluated after cleft palate repair. The interpretation of VPI considering both imaging analysis and perceptual evaluation is essential for further management. The authors retrospectively reviewed patients with repaired cleft palates who underwent assessment for velopharyngeal function, including both videofluoroscopic imaging and perceptual speech evaluation. The final diagnosis of VPI was made by plastic surgeons based on both assessment modalities. Deep learning techniques were applied for the diagnosis of VPI and compared with the human experts' diagnostic results of videofluoroscopic imaging. In addition, the results of the deep learning techniques were compared with a speech pathologist's diagnosis of perceptual evaluation to assess consistency with clinical symptoms. A total of 714 cases from January 2010 to June 2019 were reviewed. Six deep learning algorithms (VGGNet, ResNet, Xception, ResNext, DenseNet, and SENet) were trained using the obtained dataset. The area under the receiver operating characteristic curve of the algorithms ranged between 0.8758 and 0.9468 in the hold-out method and between 0.7992 and 0.8574 in the 5-fold cross-validation. Our findings demonstrated the deep learning algorithms performed comparable to experienced plastic surgeons in the diagnosis of VPI based on videofluoroscopic velopharyngeal imaging.

Augmented Reality-Based Visual Cue for Guiding Central Catheter Insertion in Pediatric Oncologic Patients.

BACKGROUND: Pediatric hemato-oncologic patients require central catheters for chemotherapy, and the junction of the superior vena cava and right atrium is considered the ideal location for catheter tips. Skin landmarks or fluoroscopic supports have been applied to identify the cavoatrial junction; however, none has been recognized as the gold standard. Therefore, we aim to develop a safe and accurate technique using augmented reality technology for the location of the cavoatrial junction in pediatric hemato-oncologic patients. METHODS: Fifteen oncology patients who underwent chest computed tomography were enrolled for Hickman catheter or chemoport insertion. With the aid of augmented reality technology, three-dimensional models of the internal jugular veins, external jugular veins, subclavian veins, superior vena cava, and right atrium were constructed. On inserting the central vein catheters, the cavoatrial junction identified using the three-dimensional models were marked on the body surface, the tip was positioned at the corresponding location, and the actual insertion location was confirmed using a portable x-ray machine. The proposed method was evaluated by comparing the distance from the cavoatrial junction to the augmented reality location with that to the conventional location on x-ray. RESULTS: The mean distance between the cavoatrial junction and augmented reality location on x-ray was 1.2 cm, which was significantly shorter than that between the cavoatrial junction and conventional location (1.9 cm; P = 0.027). CONCLUSIONS: Central catheter insertion using augmented reality technology is more safe and accurate than that using conventional methods and can be performed at no additional cost in oncology patients.

Effects of smartphone mirroring-based telepresence exercise on body composition and physical function in obese older women.

AIMS: This study aimed to develop a smartphone mirroring-based telepresence exercise program that can be performed at home while allowing for real-time feedback by instructors. METHODS: For this randomized controlled trial, 29 obese older women aged 66-87 years with ≥ 30% body fat were recruited at a senior citizen center. The intervention group was provided with the smartphone mirroring-based telepresence exercise program, in which participants exercised in their homes for 20-40 min three times a week for 12 weeks. Participants in the control group performed the same exercise program at the senior citizen center. Body composition and functional abilities were measured before and after the program. RESULTS: Women in the intervention group showed a decrease in their body fat percentage (P = 0.026) and an increase in grip strength (P = 0.008). In the control group, women demonstrated a decrease in their weight (P = 0.006) and body fat percentage (P = 0.001) and an increase in skeletal muscle (P = 0.044) and grip strength (P = 0.006). CONCLUSION: Smartphone mirroring-based telepresence exercises at home lower body fat percentage and increase muscle strength similar to traditional group exercises. They present an innovative way for obese older women to improve and maintain their health. TRIAL REGISTRATION: Clinical Research Information Service KCT0006147.

Influence of ABCB1 and CYP3A5 genetic polymorphisms on the pharmacokinetics of quetiapine in healthy volunteers.

BACKGROUND AND OBJECTIVES: Quetiapine is an atypical antipsychotic drug used to treat schizophrenia and acute episodes of mania. Quetiapine is metabolized by CYP3A enzymes including CYP3A5 and is a substrate of P-glycoprotein, an efflux drug transporter encoded by the ABCB1 gene. We assessed the effects of ABCB1 [c.1236C>T (rs1128503), c.2677G>T/A (rs2032582), c.3435C>T (rs1045642)] and CYP3A5*3 (6986A>G) (rs776746) polymorphisms on the pharmacokinetics of quetiapine in humans. MATERIALS AND METHODS: Forty healthy male individuals were enrolled, and their ABCB1 and CYP3A5 polymorphisms were assessed. After a single dose of 100 mg quetiapine was administered, plasma concentrations of quetiapine were measured for 24 h and pharmacokinetic analysis was carried out. RESULTS: The ABCB1 polymorphisms including c.1236C>T, c.2677G>T/A, and c.3435C>>T did not affect plasma levels of quetiapine, and its pharmacokinetic parameters did not differ among ABCB1 genotype groups. However, the CYP3A5*3 polymorphism significantly affected the plasma level of quetiapine and its pharmacokinetics. The peak plasma concentration of quetiapine was 208.39 ng/ml for CYP3A5*1/*1, 243.46 ng/ml for CYP3A5*1/*3, and 332.94 ng/ml for CYP3A5*3/*3 (P=0.0118). The mean AUC(inf) (area under the time vs. concentration curve from 0 to infinity) value was 627.3, 712.77, and 1045.29 ng h/ml, respectively (P=0.0017). CONCLUSION: The results indicated that the genetic polymorphism of CYP3A5*3 but not ABCB1 significantly influences the plasma level of quetiapine and its pharmacokinetics. These findings suggest that the CYP3A5 genetic polymorphism affects the disposition of quetiapine and provide a plausible explanation for interindividual variation in the disposition of this drug.

Multiplex pyrosequencing method to determine CYP2C9*3, VKORC1*2, and CYP4F2*3 polymorphisms simultaneously: its application to a Korean population and comparisons with other ethnic groups.

Warfarin is an anticoagulant that is difficult to administer because of the wide variation in dose requirements to achieve a therapeutic effect. CYP2C9, VKROC1, and CYP4F2 play important roles in warfarin metabolism, and their genetic polymorphisms are related to the variability in dose determination. In this study we describe a new multiplex pyrosequencing method to identify CYP2C9*3 (rs1057910), VKORC1*2 (rs9923231), and CYP4F2*3 (rs2108661) simultaneously. A multiplex pyrosequencing method to simultaneously detect CYP2C9*3, VKORC1*2, and CYP4F2*3 alleles was designed. We assessed the allele frequencies of the polymorphisms in 250 Korean subjects using the multiplex pyrosequencing method. The results showed 100 % concordance between single and multiplex pyrosequencing methods, and the polymorphisms identified by pyrosequencing were also validated with the direct sequencing method. The allele frequencies of these polymorphisms in this population were as follows: 0.040 for CYP2C9*3, 0.918 for VKORC1*2, and 0.416 for CYP4F2*3. Although the allele frequencies of the CYP2C9*3 and VKROC1*2 were comparable to those in Japanese and Chinese populations, their frequencies in this Korean population differed from those in other ethnic groups; the CYP4F2*3 frequency was the highest among other ethnic populations including Chinese and Japanese populations. The pyrosequencing methods developed were rapid and reliable for detecting CYP2C9*3, VKORC1*2, and CYP4F2*3. Large ethnic differences in the frequency of these genetic polymorphisms were noted among ethnic groups. CYP4F2*3 exhibited its highest allele frequency among other ethnic populations compared to that in a Korean population.

Development of Prediction Model for Intensive Care Unit Admission Based on Heart Rate Variability: A Case-Control Matched Analysis.

This study aimed to develop a predictive model for intensive care unit (ICU) admission by using heart rate variability (HRV) data. This retrospective case-control study used two datasets (emergency department [ED] patients admitted to the ICU, and patients in the operating room without ICU admission) from a single academic tertiary hospital. HRV metrics were measured every 5 min using R-peak-to-R-peak (R-R) intervals. We developed a generalized linear mixed model to predict ICU admission and assessed the area under the receiver operating characteristic curve (AUC). Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated from the coefficients. We analyzed 610 (ICU: 122; non-ICU: 488) patients, and the factors influencing the odds of ICU admission included a history of diabetes mellitus (OR [95% CI]: 3.33 [1.71-6.48]); a higher heart rate (OR [95% CI]: 3.40 [2.97-3.90] per 10-unit increase); a higher root mean square of successive R-R interval differences (RMSSD; OR [95% CI]: 1.36 [1.22-1.51] per 10-unit increase); and a lower standard deviation of R-R intervals (SDRR; OR [95% CI], 0.68 [0.60-0.78] per 10-unit increase). The final model achieved an AUC of 0.947 (95% CI: 0.906-0.987). The developed model effectively predicted ICU admission among a mixed population from the ED and operating room.

SLCO2B1 genetic polymorphisms in a Korean population: pyrosequencing analyses and comprehensive comparison with other populations.

SLCO2B1, also known as OATP2B1 (Organic Anion Transporter) or OATP-B or SLC21A9, is an organic anion uptake transporter that is encoded by the SLCO2B1 gene. In this study we assessed the frequencies of SLCO2B1 polymorphisms in a Korean population using newly developed pyrosequencing methods and compared their frequencies with those in other ethnic groups. We developed pyrosequencing methods to identify the following six SLCO2B1 non-synonymous polymorphisms: c.1175C > T (rs1621378), c.1457C > T (rs2306168), c.43C > T (rs56837383), c.935G > A (rs12422149), c.601G > A (rs35199625) and c.644A > T (rs72559740). The allele frequencies of these polymorphisms were analyzed in 227 Korean subjects. The allele frequencies of SLCO2B1 polymorphisms in the population tested were as follows: 0.0 for c.1175C > T, c.43C > T and c.644A > T; 0.2687 for c.1457C > T; 0.4273 for c.935G > A; and 0.0727 for c. 601G > A. Even though the allele frequencies of the c.1175C > T and c.1457C > T polymorphisms were comparable to those in Japanese subjects, the frequencies in this Korean population differed from those in other ethnic groups. The developed pyrosequencing methods are rapid and reliable for detecting non-synonymous SLCO2B1 polymorphisms. Large ethnic differences in the frequency of SLCO2B1 genetic polymorphisms were noted among ethnic groups. The SLCO2B1 polymorphisms at c.1175C > T, c.43C > T and c.644A > T were not found in the Korean population while c.1457C > T, c.935G > A and c.601G > A exhibited mostly higher frequencies in Koreans compared with Finnish, Caucasian and African-American populations.

User Experience of Augmented Reality Glasses-based Tele-Exercise in Elderly Women.

OBJECTIVES: The purpose of this study was to identify any difference in user experience between tablet- and augmented reality (AR) glasses-based tele-exercise programs in elderly women. METHODS: Participants in the AR group (n = 14) connected Nreal glasses with smartphones to display a pre-recorded exercise program, while each member of the tablet group (n = 13) participated in the same exercise program using an all-in-one personal computer. The program included sitting or standing on a chair, bare-handed calisthenics, and muscle strengthening using an elastic band. The exercise movements were presented first for the upper and then the lower extremities, and the total exercise time was 40 minutes (5 minutes of warm-up exercises, 30 minutes of main exercises, and 5 minutes of cool-down exercises). To evaluate the user experience, a questionnaire consisting of a 7-point Likert scale was used as a measurement tool. In addition, the Wilcoxon rank-sum test was used to assess differences between the two groups. RESULTS: Of the six user experience scales, attractiveness (p = 0.114), stimulation (p = 0.534), and novelty (p = 0.916) did not differ significantly between the groups. However, efficiency (p = 0.006), perspicuity (p = 0.008), and dependability (p = 0.049) did vary significantly between groups. CONCLUSIONS: When developing an AR glasses-based exercise program for the elderly, the efficiency, clarity, and stability of the program must be considered to meet the participants' needs.

High hydrostatic pressure extract of garlic increases the HDL cholesterol level via up-regulation of apolipoprotein A-I gene expression in rats fed a high-fat diet.

BACKGROUND: Cardiovascular disease (CVD) is the number one cause of mortality worldwide and a low high-density lipoprotein cholesterol (HDL-C) level is an important marker of CVD risk. Garlic (Allium sativum) has been widely used in the clinic for treatment of CVD and regulation of lipid metabolism. This study investigated the effects of a high hydrostatic pressure extract of garlic (HEG) on HDL-C level and regulation of hepatic apolipoprotein A-I (apoA-I) gene expression. METHODS: Male Sprague-Dawley rats were divided into two groups and maintained on a high-fat control diet (CON) or high-fat control diet supplemented with high hydrostatic pressure extract of garlic (HEG) for 5 weeks. Changes in the expression of genes related to HDL-C metabolism were analyzed in liver, together with biometric and blood parameters. RESULTS: In the HEG group, the plasma triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) levels were significantly decreased in comparison with the CON group (P < 0.05). Dietary HEG also lowered the hepatic TG and total cholesterol (TC) levels compared to the CON group. While the plasma HDL-C level and mRNA level of hepatic apoA-I, which is one of primarily proteins of HDL-C particle, were significantly increased in the HEG group compared to the CON group (P < 0.05). The gene expression of ATP-binding cassette transporter A1 (ABCA1) and lecithin:cholesterol acyltransferase (LCAT), importantly involved in the biogenesis in HDL, were also up-regulated by dietary HEG. CONCLUSIONS: These results suggest that HEG ameliorates plasma lipid profiles and attenuates hepatic lipid accumulation in the high-fat fed rats. Our findings provides that the effects of HEG on the increase of the plasma HDL-C level was at least partially mediated by up-regulation of hepatic genes expression such as apoA-I, ABCA1, and LCAT in rats fed a high-fat diet.

Tele-consent using mixed reality glasses (NREAL) in pediatric inguinal herniorrhaphy: a preliminary study.

There is an increasing demand and need for patients and caregivers to actively participate in the treatment process. However, when there are unexpected findings during pediatrics surgery, access restrictions in the operating room may lead to a lack of understanding of the medical condition, as the caregivers are forced to indirectly hear about it. To overcome this, we designed a tele-consent system that operates through a specially constructed mixed reality (MR) environment during surgery. We enrolled 11 patients with unilateral inguinal hernia and their caregivers among the patients undergoing laparoscopic inguinal herniorrhaphy between January through February 2021. The caregivers were informed of the intraoperative findings in real-time through MR glasses outside the operating room. After surgery, we conducted questionnaire surveys to evaluate the satisfaction and usefulness of tele-consent. We identified contralateral patent processus vaginalis in seven out of 11 patients, and then additionally performed surgery on the contralateral side with tele-consent from their caregivers. Most caregivers and surgeons answered positively about the satisfaction and usefulness of tele-consent. This study found that tele-consent with caregivers using MR glasses not only increased the satisfaction of caregivers and surgeons, but also helped to accommodate real-time findings by adapting surgical plan through the tele-consent.

Effect of ABCG2 genotypes on the pharmacokinetics of A771726, an active metabolite of prodrug leflunomide, and association of A771726 exposure with serum uric acid level.

OBJECTIVE: It has been reported that leflunomide and its active metabolite, A771726, are substrates of the ABCG2 (BCRP) transporter in vitro. Recent genome-wide association studies have shown that ABCG2 transporter modulates serum uric acid (UA) levels. We explored the role of ABCG2 genotypes in the pharmacokinetics of A771726 and the relationship between serum UA levels and pharmacokinetics of A771726 in healthy participants. METHODS: Twenty-four healthy individuals were recruited and genotyped for ABCG2. After administration of a single dose of 20 mg leflunomide, plasma concentrations of A771726 were measured. Serum UA levels were measured just before medication, and ABCG2 c.421C>A and c.34G> A polymorphism were genotyped. RESULTS: ABCG2 c.421C>A but not c.34G>A substantially influenced the pharmacokinetics of A771726. A771726 C(max) was 30% higher, area under the concentration-time curve (AUC) 83% larger, and oral clearance (CL/F) 41% lower in c.421C>A carriers than in noncarriers. Serum UA levels were also higher in carriers than in noncarriers and exhibited a strong and positive correlation with A771726 AUC (Spearman r = 0.6746, P = 0.0003), but a negative correlation was observed with A771726 CL/F (Spearman r = -0.6616, P = 0.0004). CONCLUSION: ABCG2 c.421C>A but not c.34G>A polymorphism appears to be a major determinant of interindividual variability in A771726 disposition. Additionally, serum UA levels exhibited a strong correlation with exposure to A771726.

Federated Learning for Thyroid Ultrasound Image Analysis to Protect Personal Information: Validation Study in a Real Health Care Environment.

BACKGROUND: Federated learning is a decentralized approach to machine learning; it is a training strategy that overcomes medical data privacy regulations and generalizes deep learning algorithms. Federated learning mitigates many systemic privacy risks by sharing only the model and parameters for training, without the need to export existing medical data sets. In this study, we performed ultrasound image analysis using federated learning to predict whether thyroid nodules were benign or malignant. OBJECTIVE: The goal of this study was to evaluate whether the performance of federated learning was comparable with that of conventional deep learning. METHODS: A total of 8457 (5375 malignant, 3082 benign) ultrasound images were collected from 6 institutions and used for federated learning and conventional deep learning. Five deep learning networks (VGG19, ResNet50, ResNext50, SE-ResNet50, and SE-ResNext50) were used. Using stratified random sampling, we selected 20% (1075 malignant, 616 benign) of the total images for internal validation. For external validation, we used 100 ultrasound images (50 malignant, 50 benign) from another institution. RESULTS: For internal validation, the area under the receiver operating characteristic (AUROC) curve for federated learning was between 78.88% and 87.56%, and the AUROC for conventional deep learning was between 82.61% and 91.57%. For external validation, the AUROC for federated learning was between 75.20% and 86.72%, and the AUROC curve for conventional deep learning was between 73.04% and 91.04%. CONCLUSIONS: We demonstrated that the performance of federated learning using decentralized data was comparable to that of conventional deep learning using pooled data. Federated learning might be potentially useful for analyzing medical images while protecting patients' personal information.

Usability Evaluation of User Requirement-Based Teleconsultation Robots: A Preliminary Report from South Korea.

BACKGROUND: Telepresence robots used to deliver a point-of-care (POC) consultation system that may provide value to enable effective decision making by healthcare providers at care sites. OBJECTIVES: This study aimed to evaluate usability of teleconsultation robots, based on endusers' needs, that can improve acceptance in future robot applications. METHODS: This is a single group postdesign study using mixed methods to assess the usability of teleconsultation robots using scenarios. To collect opinions from various departments, 15 nurses or physicians currently working at medical institutions in Korea were selected using purposive sampling. The usability evaluation was conducted on healthcare providers twice at the simulation center; the think-aloud method was used and surveys and interviews were conducted to identify problems or improvements that may arise from the use of robots in hospital settings. RESULTS: The results showed that perceived usefulness, perceived ease of use, and satisfaction level each scored 4 points or higher out of 7 points, showing usability of midhigh level. Camera angle control and robot driving functions were the most difficult. Other basic robot user interface was shown to be relatively easy. There was no difference in usability depending on the characteristics of the evaluator. Some functions including user interface were modified based on the usability test. CONCLUSION: Using robots in health care institutions may support effective communication among healthcare providers, thus contributing to health care improvement.

Effects of the ABCG2 and ABCB1 drug transporter polymorphisms on the pharmacokinetics of bicalutamide in humans.

BACKGROUNDS: Bicalutamide is an oral non-steroidal anti-androgen used in the treatment of prostate cancer. Drug transporters P-glycoprotein encoded by ABCB1 and breast cancer resistance protein (BCRP) encoded by ABCG2 are involved in the transportation of bicalutamide and its treatment failure. We evaluated the roles of ABCB1 and ABCG2 genetic polymorphisms in the pharmacokinetics of bicalutamide in humans. METHODS: After a single oral dose of 150mg bicalutamide was administered, plasma concentrations of bicalutamide were measured, and pharmacokinetic analyses were performed in 27 healthy subjects according to ABCB1 (c.1236C>T, c.2677G>T/A, and c.3435C>T) and ABCG2 (c.34G>A and c.421C>A). RESULTS: ABCB1 polymorphisms did not affect the plasma levels of bicalutamide and the pharmacokinetic parameters did not differ among ABCB1 genotype groups. However, the ABCG2 c.421C>A polymorphism significantly influenced the plasma levels and pharmacokinetics of bicalutamide gene dose-dependently. CONCLUSIONS: The ABCB1 genetic polymorphisms did not influence the pharmacokinetics of bicalutamide. However, ABCG2 c.421C>A significantly and gene dose-dependently influenced its pharmacokinetics, but c.34G>A did not.

Anti-obesity efficacy of nanoemulsion oleoresin capsicum in obese rats fed a high-fat diet.

PURPOSE: This study determined the effects of oleoresin capsicum (OC) and nanoemulsion OC (NOC) on obesity in obese rats fed a high-fat diet. METHODS: THE RATS WERE RANDOMLY SEPARATED INTO THREE GROUPS: a high-fat (HF) diet group, HF + OC diet group, and HF + NOC diet group. All groups were fed the diet and water ad libitum for 14 weeks. RESULTS: NOC reduced the body weight and adipose tissue mass, whereas OC did not. OC and NOC reduced mRNA levels of adipogenic genes, including peroxisome proliferator-activated receptor (PPAR)-γ, sterol regulatory element-binding protein-1c, and fatty acid-binding protein in white adipose tissue. The mRNA levels of genes related to ß-oxidation or thermogenesis including PPAR-α, palmitoyltransferase-1α, and uncoupling protein-2 were increased by the OC and NOC relative to the HF group. Both OC and NOC clearly stimulated AMP-activated protein kinase (AMPK) activity. In particular, PPAR-α, palmitoyltransferase-1α, uncoupling protein-2 expression, and AMPK activity were significantly increased in the NOC group compared to in the OC group. NOC decreased glycerol-3-phosphate dehydrogenase activity whereas OC did not. CONCLUSION: From these results, NOC could be suggested as a potential anti-obesity agent in obese rats fed a HF diet. The effects of the NOC on obesity were associated with changes of multiple gene expression, activation of AMPK, and inhibition of glycerol-3-phosphate dehydrogenase in white adipose tissue.

Anti-obesity effects of hot water extract and high hydrostatic pressure extract of garlic in rats fed a high-fat diet.

The effects of hot water extract of garlic (WEG) and high hydrostatic pressure extract of garlic (HEG) on obesity were investigated in rats fed a high-fat (HF) diet. Supplementation with HEG significantly reduced body weight gain and adipose tissue mass compared to those in the HF group, whereas WEG did not. Serum levels of triglycerides, total cholesterol, and LDL-cholesterol were also decreased in the HEG supplemented group compared to those in the HF group. The level of fecal triglyceride in the HEG group was higher compared to that in the HF group. The mRNA levels of adipogenic genes, such as peroxisome proliferator-activated receptor gamma (PPARγ), sterol regulatory element-binding protein-1c (SREBP-1c), and fatty acid-binding protein (aP2) were significantly decreased in both the WEG and HEG groups. Additionally, uncoupling protein 2 (UCP2) mRNA were increased clearly in the HEG group compared to that in the HF group. These results suggested that HEG more efficiently reduced body weight gain than WEG, at least partially mediated by increase of the fecal triglyceride and downregulation of adipogenic genes expression together with upregulation of UCP2 gene expression in rats fed a high-fat diet.

Effects of polymorphisms of the SLCO2B1 transporter gene on the pharmacokinetics of montelukast in humans.

Montelukast, a leukotriene receptor antagonist, is a substrate of organic anion transporting OATP2B1 encoded by the SLCO2B1. We evaluated the effects of six non-synonymous (c.1175C>T, c.1457C>T, c.43C>T, c.935G>A, c.601G>A, and c.644A>T) polymorphisms and one promoter (g.-282G>A) polymorphism on the pharmacokinetics of montelukast. A single dose of 10 mg montelukast was administered in 24 healthy subjects. Its levels were measured up to 24 hours and a pharmacokinetic analysis was performed based on the SLCO2B1 polymorphisms. We did not encounter subjects with c.1175C>T, c.43C>T, or c.644A>T polymorphisms. The remaining SLCO2B1 polymorphisms did not affect plasma levels of montelukast, and pharmacokinetic parameters of montelukast did not differ among genotype groups. Oral clearance results were as follows: (1) 3.3 L/h for c.935GG, 3.0 L/h for c.935GA, and 3.5 L/h for c.935AA; (2) 3.4 L/h for c.1457CC, 2.9 L/h for c.1457CT, and 3.2 L/h for c.1457TT; (3) 3.2 L/h for c.601GG, 3.4 L/h for c.601GA, and 3.4 L/h for c.601AA; (4) 3.2 L/h for g.-282GG, 3.4 L/h for g.-282GA, and 3.2 L/h for g.-282AA. The findings suggest that SLCO2B1 polymorphisms do not affect the pharmacokinetics of montelukast and that SLCO2B1 polymorphisms appear to be a minor determinant of inter-individual variability of montelukast.

Effect of P2Y1 and P2Y12 genetic polymorphisms on the ADP-induced platelet aggregation in a Korean population.

BACKGROUND: P2Y1 and P2Y12 receptors are expressed in platelet membranes and are involved in ADP-induced platelet aggregation. Genetic polymorphisms of P2Y1 and P2Y12 play a major role in the variation of ADP-induced platelet aggregation and in response in antiplatelet therapy. OBJECTIVE: To evaluate the allele frequencies of P2Y1 and P2Y12 genetic polymorphisms in a Korean population and to assess their role in ADP (5 µmol/L)-induced maximal platelet aggregation. METHODS: P2Y1 (c.1622A>G) and P2Y12 (i-139C>T, i-744T>C, i-ins801, c.52G>T, c.34C>T) polymorphisms were analyzed in 158 Korean healthy participants using pyrosequencing methods. Their ADP-induced maximal platelet aggregation was assessed by the turbidometric method. RESULTS: The observed allele frequencies of P2Y1 and P2Y12 were as follows: 0.3101 for P2Y1 c.1622A>G; 0.1804 for P2Y12 i-139C>T, 0.1804 for i-744T>C, 0.1804 for i-801insA, 0.1266 for P2Y12 c.52G>T, and 0.2658 for P2Y12 c.34C>T. ADP-induced maximal platelet aggregation was not influenced by the P2Y1 c.1622A>G polymorphism and was also not affected by three intronic P2Y12 polymorphisms and the P2Y12 c.34C>T polymorphism. However, the P2Y12 c.52G>T polymorphism caused a substantial difference in ADP-induced maximal platelet aggregation (62.75% for c.52GG, 66.27% for c.52GT, and 80.60% for c.52TT; P=0.0092). CONCLUSIONS: The P2Y1 and P2Y12 genes were very polymorphic in a Korean population. Three intronic P2Y12 polymorphisms (i-139C>T, i-744T>C, i-801insA) were in complete linkage disequilibrium but not with the c.52C>T polymorphism in this population. Maximal platelet aggregation in response to ADP is associated with the c.52C>T polymorphism but not with the three intronic polymorphisms or the P2Y1 c.1622A>T polymorphism.

Influence of orthodontic adhesives and clean-up procedures on the stain susceptibility of enamel after debonding.

OBJECTIVE: To determine the influence of the type of orthodontic adhesive system, such as conventional acid-etching (CE) and self-etching primers (SEPs), on the stain susceptibility of enamel surface after debonding. Effects of clean-up procedures on the enamel surface were also determined. MATERIALS AND METHODS: Two types and four brands of adhesive systems were investigated using 135 human premolars. Unbonded teeth were used as controls. Three-dimensional scanning of the enamel surface was performed before bracket bonding, after debonding, and after clean-up procedures. The color of each tooth was measured before bracket bonding and again after debonding and clean-up procedures. This was followed by methylene blue staining. The stain susceptibility of the enamel surface was measured after finishing only (F-condition) and after finishing/polishing (FP-condition). RESULTS: After debonding, the amount of residual adhesive resins in CE materials was greater than that in SEP materials. For the F-condition, staining color change in SEP materials was significantly higher than that in CE materials. For the FP-condition, staining color change in both CE and SEP materials was not different from those of the control. CONCLUSIONS: The SEP system would show less stain susceptibility if the thin residual adhesive resin layer after debonding is removed by polishing.