Background and Objectives: Identifying patients with high bleeding risk (HBR) is important when making decisions for antiplatelet therapy strategy. This study evaluated the impact of ticagrelor monotherapy after 3-month dual antiplatelet therapy (DAPT) according to HBR in acute coronary syndrome (ACS) patients treated with drug eluting stents (DESs). Methods: In this post-hoc analysis of the TICO trial, HBR was defined by 2 approaches: meeting Academic Research Consortium for HBR (ARC-HBR) criteria or Predicting Bleeding Complications in Patients Undergoing Stent Implantation and Subsequent DAPT (PRECISEDAPT) score ≥25. The primary outcome was a 3–12 months net adverse clinical event (composite of major bleeding and adverse cardiac and cerebrovascular events). Results: Of the 2,980 patients without adverse events during the first 3 months after DES implantation, 453 (15.2%) were HBR by ARC-HBR criteria and 504 (16.9%) were HBR by PRECISE-DAPT score. The primary outcome rate was higher in HBR versus non-HBR patients (by ARC-HBR criteria: hazard ratio [HR], 2.87; 95% confidence interval [CI], 1.76– 4.69; p<0.001; by PRECISE-DAPT score: HR, 3.09; 95% CI, 1.92–4.98; p<0.001). Ticagrelor monotherapy after 3-month DAPT was associated with lower primary outcome rate than ticagrelor-based 12-month DAPT regardless of HBR by ARC-HBR criteria, with similar magnitudes of therapy effect for HBR and non-HBR patients (p-interaction=0.400). Results were consistent by PRECISE-DAPT score (p-interaction=0.178). Conclusions In ACS patients treated with DESs, ticagrelor monotherapy after 3-month DAPT was associated with lower rate of adverse clinical outcomes regardless of HBR, with similar magnitudes of therapy effect between HBR and non-HBR.Trial Registration: ClinicalTrials.gov Identifier: NCT02494895

Background/Aims: Renal ischemia followed by reperfusion (I/R) is a leading cause of acute kidney injury (AKI), which is closely associated with high morbidity and mortality. Studies have shown that induced pluripotent stem cell (iPSC)-derived mesenchymal stem cells (iMSCs) exert powerful therapeutic effects in renal ischemia. However, the efficacy of iMSC-derived exosomes (iExo) on I/R injuries remains largely unknown. Methods: Human iPSCs were differentiated into iMSCs using a modified one-step method. Ultrafiltration, combined with purification, was used to isolate iExo from iMSCs. iExo was administered following I/R injury in a mouse model. The effect of iExo on I/R injury was assessed through changes in renal function, histology, and expression of oxidative stress, inflammation, and apoptosis markers. Further, we evaluated its association with the extracellular signal-regulated kinase (ERK) 1/2 signaling pathway. Results: Mice subjected to I/R injury exhibited typical AKI patterns; serum creatinine level, tubular necrosis, apoptosis, inflammatory cytokine production, and oxidative stress were markedly increased compared to sham mice. However, treatment with iExo attenuated these changes, significantly improving renal function and tissue damage, similar to the renoprotective effects of iMSCs on I/R injury. Significant induction of activated ERK 1/2 signaling molecules was observed in mice treated with iExo compared to those in the I/R injury group. Conclusions The present study demonstrates that iExo administration ameliorated renal damage following I/R, suggesting that iMSC-derived exosomes may provide a novel therapeutic approach for AKI treatment.

Objective: To analyze the characteristics and trends of scientific publications on thyroid ultrasound (US) from 2001 to 2020, specifically examining the differences among disciplines. Materials and Methods: The MEDLINE database was searched for scientific articles on thyroid US published between 2001 and 2020 using the PubMed online service. The evaluated parameters included year of publication, type of document, topic, funding, first author’s specialty, journal name, subject category, impact factor, and quartile ranking of the publishing journal, country, and language. Relationships between the first author’s specialty (radiology, internal medicine, surgery, otorhinolaryngology, and miscellaneous) and other parameters were analyzed. Results: A total of 2917 thyroid US publications were published between 2001 and 2020, which followed an exponential growth pattern, with an annual growth rate of 11.6%. Radiology produced the most publications (n = 1290, 44.2%), followed by internal medicine (n = 716, 24.5%), surgery (n = 409, 14.0%), and otorhinolaryngology (n = 171, 5.9%). Otorhinolaryngology and internal medicine published significantly more case reports than radiology (p < 0.001, each). Radiology published a significantly higher proportion of publications on imaging diagnosis (p < 0.001 for all) and a significantly lower proportion of publications on biopsy (p < 0.001 for all) than the other disciplines. Publications produced by radiology authors were less frequently published in Q1 journals than those from other disciplines (p < 0.005 for internal medicine and miscellaneous disciplines and < 0.01 for surgery and otorhinolaryngology). China contributed the greatest number of publications (n = 622, 21.3%), followed by South Korea (n = 478, 16.4%) and the United States (n = 468, 16.0%). Conclusion Radiology produced the most publications for thyroid US than any other discipline. Radiology authors published more notably on imaging diagnosis compared to other topics and in journals with lower impact factors compared to authors in other disciplines.

Helicobacter pylori infection is one of the most common infectious diseases worldwide. Although the prevalence of H. pylori is gradually decreasing, approximately half of the world's population still becomes infected with this disease. H. pylori is responsible for substantial gastrointestinal morbidity worldwide, with a high disease burden. It is the most common cause of gastric and duodenal ulcers and gastric cancer. Since the revision of the H. pylori clinical practice guidelines in 2013 in Korea, the eradication rate of H. pylori has gradually decreased with the use of a clarithromycin-based triple therapy for 7 days. According to a nationwide randomized controlled study conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research released in 2018, the intention-to-treat eradication rate was only 63.9%, which was mostly due to increased antimicrobial resistance, especially from clarithromycin. The clinical practice guidelines for the treatment of H. pylori were updated according to evidence-based medicine from a meta-analysis conducted on a target group receiving the latest level of eradication therapy. The draft recommendations developed based on the meta-analysis were finalized after an expert consensus on three recommendations regarding the indication for treatment and eight recommendations for the treatment itself. These guidelines were designed to provide clinical evidence for the treatment (including primary care treatment) of H. pylori infection to patients, nurses, medical school students, policymakers, and clinicians. These may differ from current medical insurance standards and will be revised if more evidence emerges in the future.

Helicobacter pylori (H. pylori) infection is one of the most common infectious diseases worldwide. Although its incidence is gradually decreasing, about half of the world's population still get infected. H. pylori infection is responsible for substantial gastrointestinal morbidity worldwide. It is the most common cause of gastric and duodenal ulcers as well as gastric cancer. Since the revision of the H. pylori Clinical Practice Guidelines in 2013, the eradication rate of H. pylori has gradually decreased with the use of classical triple therapy, wherein amoxicillin, clarithromycin, and proton pump inhibitors are administered, for 7 days. According to a nationwide randomized controlled study conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research released in 2018, the intention-to-treat eradication rate was only 63.9%, which was due to increased antimicrobial resistance induced by the use of antibiotics, especially clarithromycin. The update of clinical practice guideline for treatment of H. pylori was developed based on evidence-based medicine by conducting a meta-analysis. The draft recommendations were finalized after expert consensus on three recommendations regarding the indication for treatment and eight recommendations on the treatment itself. These guidelines are designed to provide patients, nurses, medical school students, policymakers, and clinicians with clinical evidence to guide primary care and treatment of H. pylori infection. These may differ from current medical insurance standards and will be revised further, if necessary, based on research-based evidence.

Background/Aims: Standard triple therapy, including a proton pump inhibitor, clarithromycin, and amoxicillin, has been recommended as the first-line for Helicobacter pylori infection. However, the eradication rate of standard triple therapy has declined over the past years because of the increasing resistance to clarithromycin in Korea. We analyzed the eradication rates and the 10-year change in the eradication rates in Korea. Methods: PubMed, EMBASE, the Cochrane Library, and KoreaMed were searched for studies published between January 2007 and June 2018. The pooled eradication rates and their 95% CIs were estimated using a random-effect logistic regression model. Results: Twenty-six randomized controlled studies on standard triple therapy conducted in Korea were selected. The intention-to-treat (ITT) and per protocol analyses showed pooled eradication rates of standard triple therapy of 71.6% (95% CI, 69.9~73.3%) and 79.6% (95% CI, 76.6~82.2%), respectively. The eradication rate decreased with time. The ITT analysis showed that the 14-day therapy (78.1% [95% CI, 75.2~80.7%]) had significantly higher eradication rates than the 7-day therapy (70.0% [95% CI, 68.5~71.4%]) (P<0.01). Conclusions These results suggest that the eradication rate of standard triple therapy, as the first-line therapy, has shown an unacceptable decrease. The eradication rate increased when the duration of therapy was increased to 14 days, but it was not satisfactory. Therefore, other treatment regimens or therapies based on susceptibility tests should be considered for the first-line therapy.

Background/Aims: The eradication rate of the first-line standard triple therapy (STT) for Helicobacter pylori (H. pylori) infection has decreased since 2000; therefore, other first-line therapies are required. This study was aimed at investigating the efficacy of bismuth-containing quadruple therapy (PBMT) for first-line H. pylori eradication compared to STT, sequential therapy (SQT), and concomitant therapy (CT). Materials and Methods: The Ovid-MEDLINE, Koreamed, EMBASE, KMBASE, and Cochrane Library databases were searched from January 2008 to July 2018. All identified randomized controlled trials (RCTs) comparing PBMT and non-PBMT for first-line H. pylori eradication therapy were included in the final analysis. Results: A total of 3,653 patients from seven RCTs were enrolled. The pooled eradication rates of PBMT by intention-to-treat (ITT) and per-protocol (PP) analyses were 82.1% (95% CI, 68.2~90.8%) and 88.8% (95% CI, 77.1~94.9%), respectively. However, no statistically significant difference was observed in eradication rates of the 10- or 14-day PBMT as compared to 14-day STT, 10-day SQT, and 10-day CT in ITT and PP analyses. PBMT was significantly higher in adverse events than in the other eradication regimens (RR, 1.64; 95% CI, 1.11~2.44). Considerable heterogeneity in adverse events was observed among studies (χ2=88.7; P<0.001, I2=93%). Conclusions PBMT can be the first-line treatment for H. pylori eradication in Korea when other first-line options, including STT, SQT, or CT, are unavailable due to their high adverse event rates.

Background/Aims: As antibiotic resistance increases and new first-line therapies emerge, salvage therapies for Helicobacter pylori (H. pylori) eradication failures are becoming more common and complicated. This study aimed to systematically review overall salvage regimens after previous failure of H. pylori eradication. Materials and Methods: A systematic review of randomized clinical trials evaluating salvage therapies after previous H. pylori eradication failure was performed. A meta-analysis was conducted when an adequate number of studies suitable for grouping was found. Results: Overall, 36 studies with 77 treatment arms were identified, and they were highly heterogeneous regarding previously failed regimens and salvage regimens under comparison. Bismuth quadruple therapy after failure of standard triple therapy showed a pooled intention-to-treat (ITT) eradication rate of 75.5% (95% CI, 71.6~79.1%), and the rates were significantly higher with 14-day therapy than 7-day therapy by 9% (95% CI, 2~15%). Levofloxacin triple therapy after failure of standard triple therapy demonstrated a pooled ITT eradication rate of 73.3% (95% CI, 68.4~77.3%). In direct comparison, the two regimens were not significantly different in eradication rates. No study evaluated salvage regimens after the failure of bismuth or non-bismuth quadruple therapy. Conclusions The current studies regarding salvage regimens are highly heterogeneous. Bismuth quadruple therapy and levofloxacin triple therapy may be a reliable option after failure of standard triple therapy, but the regional profile of antibiotic resistance should be considered. Further studies are needed for salvage regimens after failure of non-bismuth or bismuth quadruple therapy.

Helicobacter pylori infection is one of the most common infectious diseases worldwide. H. pylori is responsible for substantial gastrointestinal morbidity with a high disease burden. Since the revision of the H. pylori Clinical Practice Guidelines in 2013 in Korea, the eradication rate of H. pylori has gradually decreased with the use of a clarithromycin based triple therapy. According to a nationwide randomized controlled study by the Korean College of Helicobacter and Upper Gastrointestinal Research released in 2018, the intention-to-treat eradication rate was only 63.9%, which was mostly due to increased antimicrobial resistance to clarithromycin. The clinical practice guidelines for treatment of H. pylori were updated based on evidence-based medicine from a meta-analysis conducted on a target group receiving the latest level of eradication therapy. The draft recommendations developed based on the meta-analysis were finalized after expert consensus on three recommendations regarding the indication for treatment and eight recommendations on the treatment itself. These guidelines were designed to provide clinical evidence for the treatment of H. pylori to patients, nurses, medical school students, policymakers, and clinicians. These may differ from current medical insurance standards, and will be revised if more evidence emerges in the future.

Helicobacter pylori (H. pylori) infection is one of the most common infectious diseases worldwide. Although its incidence is gradually decreasing, about half of the world's population still get infected. H. pylori infection is responsible for substantial gastrointestinal morbidity worldwide. It is the most common cause of gastric and duodenal ulcers as well as gastric cancer. Since the revision of the H. pylori Clinical Practice Guidelines in 2013, the eradication rate of H. pylori has gradually decreased with the use of classical triple therapy, wherein amoxicillin, clarithromycin, and proton pump inhibitors are administered, for 7 days. According to a nationwide randomized controlled study conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research released in 2018, the intention-to-treat eradication rate was only 63.9%, which was due to increased antimicrobial resistance induced by the use of antibiotics, especially clarithromycin. The update of clinical practice guideline for treatment of H. pylori was developed based on evidence-based medicine by conducting a meta-analysis. The draft recommendations were finalized after expert consensus on three recommendations regarding the indication for treatment and eight recommendations on the treatment itself. These guidelines are designed to provide patients, nurses, medical school students, policymakers, and clinicians with clinical evidence to guide primary care and treatment of H. pylori infection. These may differ from current medical insurance standards and will be revised further, if necessary, based on research-based evidence.