Background: As the importance of the esthetic function of teeth increases, the use of esthetic restoration materials and whitening treatment are increasing. The purpose of this study was to investigate the color change of esthetic restoration materials upon using staining and whitening toothpaste. Methods: Light curing (LC) packable composite resin, LC flowable resin, LC glass ionomer (GI), and self-curing GI specimens were colored in coffee or curry for three hours a day for seven days. After that, regular toothpaste, whitening toothpaste containing hydrogen peroxide, and whitening toothpaste containing activated charcoal were applied for three minutes three times a day for two weeks. Luminosity (L), chromaticity a (a), and chromaticity b (b) were measured using a spectrophotometer once a week. Results: In the coffee-colored group, the change in L2 *a2 *b2 (E2 ) with time was significant (p=0.004), there was no difference for different toothpaste types (p=0.646), and there was significant difference (p＜0.001) for different esthetic restorative materials.The change of E2 in the curry-colored group was significant only for different esthetic restorative materials (p＜0.001). In the coffee-colored group, the L, a, and b values of the light-curing GI showed greater change than other materials after staining and one week after whitening, turning dark, red, and yellow. In the curry-colored group, L did not differ for different materials and times, and a and b showed the greatest difference in light-curing GI after staining and one and two weeks after whitening. Conclusion The use of whitening toothpaste for two weeks was not different from the use of general toothpaste in the removal of staining or whitening. Since light-curing GI is the most vulnerable to coloration, it is recommended that coloring by food chromogen should be explained in advance, before using light-curing GI for teeth restoration.

YH4808 is a novel potassium-competitive acid blocker that was developed as a therapeutic agent for gastric acid-related diseases; it may replace proton pump inhibitors, which are widely used in combination with amoxicillin and clarithromycin for Helicobacter pylori eradication. We compared the pharmacokinetic (PK) profiles and safety of amoxicillin, clarithromycin, and YH4808 used as monotherapies or in combination for evaluating potential drug interactions. An open-label, randomized, single-dose, Latin-square (4 × 4) crossover study was conducted in 32 healthy Korean volunteers. Subjects were randomly assigned to one of the 4 treatment sequences that consisted of 4 periods separated by 21-day washout intervals. PK parameters of YH4808, amoxicillin and clarithromycin administered in combination were compared with those of the respective monotherapies. The geometric mean ratios of the maximum concentration (Cmax) and the area under the time-concentration curve from time zero to time of the last quantifiable concentration (AUClast) of YH4808 increased during the triple therapy by 48.6% and 29.1%, respectively. Similarly, the Cmax and AUClast of M3 (active metabolite of YH4808) increased by 23.3% and 16.0%, respectively. The Cmax and AUClast of clarithromycin increased by 27.4% and 30.5%, and those of 14-hydroxyclarithromycin were increased by 23.1% and 32.4%, respectively. The corresponding amoxicillin values decreased during the triple therapy by 21.5% and 15.6%, respectively. There was no clinically significant change in safety assessment related to either monotherapies or triple therapy. In conclusion, amoxicillin, clarithromycin and YH4808 administered as triple therapy did not exhibit significant PK interactions and were not associated with safety issues.

YH4808 is a novel selective potassium-competitive acid blocker demonstrated to be safe and to have inhibitory effects against gastric acid secretion in previous studies. A randomized, open-label, multiple-dose, 3-treatment, 1-period, parallel design study was conducted to compare the Helicobacter pylori eradication rates and acid suppression capacities of three regimens in 60 healthy subjects with H. pylori-positive, and the potential of YH4808 to replace proton-pump inhibitors (PPIs) in standard regimens for H. pylori eradication. Group 1 received YH4808, amoxicillin, and clarithromycin as a novel triple regimen, while Group 2 received YH4808 and amoxicillin only, and Group 3 received esomeprazole, amoxicillin, and clarithromycin, as the standard triple regimen. H. pylori eradication rates were 85.0% for Group 1, 25.0% for Group 2, and 83.3% for Group 3. Relative response rate between Group 1 and 3 was 1.02 (0.50–2.07; 95% CI, χ2 test p = 0.8881). Furthermore, the novel triple regimen, YH4808, amoxicillin, and clarithromycin, stably inhibited acid secretion and maintained a gastric pH greater than 4 or 5 for 24 hours, which was comparable to the pH range in the standard triple regimen. However, the onset times of the YH4808 regimens were earlier than that for the regimens using esomeprazole. There were no differences in the incidences or severity of adverse events among the three groups. Overall, the novel triple regimen was safe and well-tolerated. YH4808 could replace PPIs in standard triple regimens used for H. pylori eradication.

YH4808 is a novel potassium-competitive acid blocker developed for gastric acid-related disorders. Previous studies indicate its potential to improve symptoms of gastric acid-related disorders. The current study was aimed to find the optimal regimen of YH4808 for night time pH control. This study was performed in two parts. Each was a randomized, open-label, active-controlled, multiple-doses, two-treatment, two-period crossover study conducted in 20 healthy Korean volunteers. Subjects were randomly assigned to one of the four groups.The three groups received different dosage regimens of YH4808 (100 mg twice a day, 200 mg once a day, or 200 mg twice a day), and the fourth group received esomeprazole 40 mg twice a day. The pharmacokinetic parameters demonstrated that the systemic exposure of YH4808 increased in a dose-proportional manner. The difference in the proportion of time above pH 4 over 24 h from the baseline was the greatest in the group receiving YH4808 200 mg twice a day. The values of the area under the effect curve at night time (12 A.M.–7 A.M.) were higher in all YH4808 groups than in the esomeprazole group. However, the differences among the YH4808 groups were not statistically significant (p > 0.05). YH4808 exhibited potential for better pH control during the night in comparison to esomeprazole. The optimal regimen for night time pH control among all the YH4808 regimens was 200 mg twice a day.

YH4808 is a novel selective potassium-competitive acid blocker demonstrated to be safe and to have inhibitory effects against gastric acid secretion in previous studies. A randomized, open-label, multiple-dose, 3-treatment, 1-period, parallel design study was conducted to compare the Helicobacter pylori eradication rates and acid suppression capacities of three regimens in 60 healthy subjects with H. pylori-positive, and the potential of YH4808 to replace proton-pump inhibitors (PPIs) in standard regimens for H. pylori eradication. Group 1 received YH4808, amoxicillin, and clarithromycin as a novel triple regimen, while Group 2 received YH4808 and amoxicillin only, and Group 3 received esomeprazole, amoxicillin, and clarithromycin, as the standard triple regimen. H. pylori eradication rates were 85.0% for Group 1, 25.0% for Group 2, and 83.3% for Group 3. Relative response rate between Group 1 and 3 was 1.02 (0.50–2.07; 95% CI, χ2 test p = 0.8881). Furthermore, the novel triple regimen, YH4808, amoxicillin, and clarithromycin, stably inhibited acid secretion and maintained a gastric pH greater than 4 or 5 for 24 hours, which was comparable to the pH range in the standard triple regimen. However, the onset times of the YH4808 regimens were earlier than that for the regimens using esomeprazole. There were no differences in the incidences or severity of adverse events among the three groups. Overall, the novel triple regimen was safe and well-tolerated. YH4808 could replace PPIs in standard triple regimens used for H. pylori eradication.

Background: Despite significant technological advances in the implantable pulse generator (IPG), complications can still occur. We report a case that unexpected extrusion of the IPG of spinal cord stimulation (SCS) was promptly identified and successfully removed without any complications. Case: After a car accident 4 years ago, a 55-year-old man who was diagnosed with complex local pain syndrome in his right leg. The SCS was inserted with 2 leads, with the IPG being implanted in the right lower abdomen region. Four years later, he developed extrusion of the IPG from his abdominal region. This unexpected extrusion may have been related to pressure necrosis caused by continued compression of pocket site where a belt was frequently tied. The IPG and the leads were successfully removed without infection occurring. Conclusions To prevent unexpected extrusion of IPG, it is necessary to consider in advance whether the pocket site is pressed against the belt.

In November 2021, 14 international travel-related severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.529 (omicron) variant of concern (VOC) patients were detected in South Korea. Epidemiologic investigation revealed community transmission of the omicron VOC. A total of 80 SARS-CoV-2 omicron VOC-positive patients were identified until December 10, 2021 and 66 of them reported no relation to the international travel.There may be more transmissions with this VOC in Korea than reported.