Sex-based outcomes on unguided de-escalation from ticagrelor to clopidogrel in stabilized patients with acute myocardial infarction undergoing percutaneous coronary intervention: a post-hoc analysis of the TALOS-AMI

Background

The TALOS-AMI study highlighted the effectiveness of a de-escalation strategy shifting from ticagrelor to clopidogrel 1 month after percutaneous coronary intervention (PCI), resulting in significant reduction in clinical events, primarily attributed to a substantial decrease in bleeding events. Nevertheless, the impact of this strategy on outcomes based on sex remains unclear.

Methods

This was a post-hoc analysis of the TALOS-AMI study. At 1 month after PCI, patients who remained adherent to aspirin and ticagrelor without experiencing major adverse events were randomized into either the de-escalation group (clopidogrel plus aspirin) or the active control group (ticagrelor plus aspirin) for an additional 12 months. The primary endpoint encompassed a composite of cardiovascular death, myocardial infarction, stroke, and Bleeding Academic Research Consortium bleeding type 2 or greater at 12 months after randomization.

Results

Among the 2,697 patients included in this study, 454 (16.8%) were women. Women, characterized by older age and a higher prevalence of hypertension, diabetes, impaired renal function, and non-ST-segment myocardial infarction, exhibited a lower primary endpoint at 12 months compared to men [adjusted hazards ratio (HR), 0.60; 95% confidence interval (CI), 0.37-0.95; P = 0.03]. Compare to the active control group, the de-escalation group demonstrated a reduced risk of the primary endpoint in both women (adjusted HR, 0.38; 95% CI, 0.15-0.95; P = 0.039) and men (adjusted HR, 0.56; 95% CI, 0.40-0.79; P = 0.001) (interaction P = 0.46).

Conclusions

In stabilized patients post-PCI with drug-eluting stents for acute myocardial infarction, the primary endpoint was lower among women compared to men. In this cohort, the benefits of an unguided de-escalation strategy from ticagrelor to clopidogrel were comparable in women and men.

Healing and stent coverage with the new ultrathin sirolimus-eluting stent with abluminal biodegradable polymer

BACKGROUND

Genoss drug-eluting stent (DES) (Genoss Company Limited) is a new ultrathin sirolimus-eluting stent with an abluminal biodegradable polymer and a cobalt-chromium platform.

AIMS

The aim of this study was to evaluate vascular healing and neointimal coverage after implantation of the Genoss DES using optical coherence tomography (OCT) 6 months postimplantation.

METHODS

From August 22, 2019 to June 17, 2020, this multicenter, observational, investigator-initiated study enrolled 20 patients who underwent OCT examination 6 months after Genoss DES implantation and provided informed consent. An analyst, blinded to the patients' and procedural information analyzed OCT images at an independent core laboratory.

RESULTS

Of the 20 patients, 19 with 27 stents in 21 lesions from 21 vessels were included in the analysis, while one patient withdrew consent and was unwilling to undergo follow-up OCT. OCT analysis was performed 204.4 ± 31.9 days after Genoss DES implantation. A total of 4285 stent struts from 661 cross-sections were analyzed. Strut tissue coverage was observed in 98.7 ± 4.3% of struts, with 0.1 ± 1.2% malapposed struts per lesion. The mean thickness of neointimal hyperplasia (NIH) on the covered struts was 0.12 ± 0.04 mm.

CONCLUSIONS

Six months after stent implantation, most Genoss DES struts were covered with a thin layer of NIH that was evenly distributed along the stent length. This pilot study evaluated the outcomes of 6 months dual antiplatelet therapy in the context of ultrathin strut stents, providing insight into developing ethical standards and a scientific foundation for conducting an adequately designed clinical trial.

Association of Clinical Outcomes With Sex in Patients Receiving Chronic Maintenance Antiplatelet Monotherapy After Percutaneous Coronary Intervention: A Post Hoc Gender Analysis of the HOST-EXAM Study

Background Clopidogrel monotherapy was more effective in reducing the risk of adverse clinical events than aspirin monotherapy in patients who underwent percutaneous coronary intervention (PCI) with drug-eluting stent (DES), according to the HOST-EXAM (Harmonizing Optimal Strategy for Treatment of Coronary Artery Stenosis-Extended Antiplatelet Monotherapy) trial. However, it remains unknown whether these effects differ based on sex. Methods and Results This was a prespecified secondary analysis of HOST-EXAM in South Korea. Patients who maintained dual antiplatelet therapy without adverse clinical events for 6 to 18 months after PCI with DES were included. The primary end point was a composite of all-cause mortality, nonfatal myocardial infarction, stroke, acute coronary syndrome, or Bleeding Academic Research Consortium (BARC) bleeding type ≥3 at 24 months after randomization. The bleeding end point was BARC types 2 to 5. The primary end point was comparable between the sexes (adjusted hazard ratio [HR], 0.79 [95% CI, 0.62-1.02]; P=0.067), and the bleeding end point (adjusted HR, 0.79 [95% CI, 0.54-1.17]; P=0.240) was also similar. Compared with aspirin, clopidogrel was associated with lower risk of primary composite end point (adjusted HR, 0.70 [95% CI, 0.55-0.89]; P=0.004) and bleeding end point (adjusted HR, 0.65 [95% CI, 0.44-0.96]; P=0.031) in men but not in women. Conclusions The primary composite end point and bleeding events were comparable between the sexes during chronic maintenance antiplatelet monotherapy after PCI with DES. Clopidogrel monotherapy, compared with aspirin, significantly reduced the risk of the primary composite end point and bleeding events in men. However, the beneficial effect of clopidogrel on the primary end point and bleeding events was mitigated in women. Registration Information clinicaltrials.gov. Identifier: NCT02044250.

Coronary artery aneurysm formation after paclitaxel-coated balloon-only intervention for de novo coronary chronic total occlusion

Background

Although coronary artery aneurysm (CAA) is an uncommon complication of drug-coated balloon (DCB) treatment, the incidence and mechanisms CAA formation after DCB intervention for chronic total occlusion (CTO) remains to be clarified. The aim of this study was to investigate the incidence of CAA after DCB intervention for the treatment of CTO of coronary arteries.

Materials and methods

This was a retrospective analysis of 82 patients, contributing 88 vessels, who underwent successful DCB-only treatment for de novo CTO lesions. Follow-up angiography was performed in all cases, at a mean 208.5 (interquartile range [IQR]: 174.8 to 337.5) days after the index procedure.

Results

CAA was identified in seven vessels, in seven patients, at the site of previous successful DCB-only treatment. Of these, six were fusiform in shape and one saccular, with a mean diameter of 4.2 ± 1.0 mm and length of 6.7 ± 2.6 mm. Six CAAs developed at the CTO inlet site, and all CAAs occurred at the lesions following dissection immediately after DCB treatment. CAAs were not associated with an increased risk of major clinical events over the median follow-up of 676.5 (IQR: 393.8 to 1,304.8) days.

Conclusion

The incidence of CAA after DCB-only treatment for CTO lesions was 8.0% in this study. Further research is warranted, using intravascular imaging, to clarify the mechanism of DCB-related CAA formation and prognosis.

Sex-related impact on clinical outcomes of patients treated with drug-eluting stents according to clinical presentation: Patient-level pooled analysis from the GRAND-DES registry

BACKGROUND

The contribution of sex and initial clinical presentation to the long-term outcomes in patients undergoing percutaneous coronary intervention (PCI) is still debated.

METHODS

Individual patient data from 5 Korean-multicenter drug-eluting stent (DES) registries (The GRAND-DES) were pooled. A total of 17,286 patients completed 3-year follow-up (5216 women and 12,070 men). The median follow-up duration was 1125 days (interquartile range 1097-1140 days), and the primary endpoint was cardiac death at 3 years.

RESULTS

The clinical indication for PCI was stable angina pectoris (SAP) in 36.8%, unstable angina pectoris (UAP) or non-ST-segment elevation myocardial infarction (NSTEMI) in 47.4%, and ST-segment elevation myocardial (STEMI) in 15.8%. In all groups, women were older and had a higher proportion of hypertension and diabetes mellitus compared with men. Women presenting with STEMI were older than women with SAP, with the opposite seen in men. There was no sex difference in cardiac death for SAP or UAP/NSTEMI. In STEMI patients, the incidence of cardiac death (7.9% vs. 4.4%, p = 0.001), all-cause mortality (11.1% vs. 6.9%, p = 0.001), and minor bleeding (2.2% vs. 1.2%, p = 0.043) was significantly higher in women. After multivariable adjustment, cardiac death was lower in women for UAP/NSTEMI (HR 0.69, 95% CI 0.53-0.89, p = 0.005), while it was similar for STEMI (HR 0.97, 95% CI 0.65-1.44, p = 0.884).

CONCLUSIONS

There was no sex difference in cardiac death after PCI with DES for SAP and UAP/NSTEMI patients. In STEMI patients, women had worse outcomes compared with men; however, after the adjustment of confounders, female sex was not an independent predictor of mortality.

Clinical Outcomes of Drug-Coated Balloon Treatment After Successful Revascularization of de novo Chronic Total Occlusions

Background

The safety and efficacy of drug-coated balloon (DCB) treatment for de novo coronary chronic total occlusion (CTO) remain uncertain. The aim of this study was to evaluate the outcomes of DCB only treatment for de novo CTO.

Methods

In this retrospective study, 101 vessels with de novo CTO lesions dilated by balloon angioplasty with thrombolysis in myocardial infarction flow grade 3 were included. Among them, 93 vessels successfully treated with DCB only treatment were analyzed. The study endpoint was major adverse cardiac events (MACE) at 2 years, a composite of cardiac death, non-fatal myocardial infarction (MI), target vessel revascularization (TVR), and target vessel thrombosis. The secondary endpoint was late lumen loss (LLL) on follow-up coronary angiography.

Results

All 84 patients were followed up clinically, and 67 vessels underwent scheduled coronary angiography after 6 months. There were no procedural complications, and three vessels required bailout-stenting. The median follow-up was 720 days (interquartile range [IQR]; 406–1,268 days). MACE occurred in 8.3% of the patients after 1 year, including cardiac death (1.2%), TVR (7.1%), and no non-fatal MI and target vessel thrombosis. Two years after treatment, MACE occurred in 16.7% of the patients, including cardiac death (2.4%), non-fatal MI (3.6%), TVR (13.1%), and no target vessel thrombosis. The mean LLL was 0.03 ± 0.53 mm. Binary restenosis occurred in 14.9% of the treated vessels, and 3.0% of the vessels had late re-occlusion on follow-up coronary angiography.

Conclusions

If the result of revascularization using balloon angioplasty is good, the clinical outcomes of DCB only treatment of de novo CTOs at the 2-year follow-up are encouraging, with a low rate of hard endpoints and acceptable MACE rates (Clinical Trial Registration Information; Impact of Drug-coated Balloon Treatment in de novo Coronary Lesion; NCT04619277).

Comparison of 2 Different Paclitaxel-Coated Balloons in Coronary In-Stent Restenosis: A Randomized Controlled Trial

BACKGROUND

Drug-coated balloons (DCBs) offer an effective treatment for in-stent restenosis (ISR). The Genoss DCB is a novel paclitaxel-coated balloon with a shellac plus vitamin E excipient that enhances drug delivery to the target lesion, minimizing restenosis.

OBJECTIVES

This study aimed to investigate the angiographic efficacy, clinical safety, and effectiveness of the novel shellac plus vitamin E-based DCB in a randomized controlled trial designed to enable regulatory approval of this new device in South Korea.

METHODS

This noninferiority trial randomized patients experiencing their first ISR to the novel shellac plus vitamin E-based DCB or the reference SeQuent Please iopromide-based DCB in a 1:1 ratio. All patients underwent planned angiographic and clinical follow-up at 6 months. The study was powered for the primary endpoint of 6 months in-segment late lumen loss (LLL).

RESULTS

A total of 82 patients from 7 centers were randomized to either the novel shellac plus vitamin E-based DCB group (n = 41) or the reference iopromide-based DCB group (n = 41). The 6-month in-segment LLL was 0.15 ± 0.43 mm with the novel DCB compared with 0.24 ± 0.39 mm with the reference device. The 1-sided 97.5% upper confidence limit of the difference was 0.13 mm, lower than the noninferiority limit of 0.29 mm, achieving noninferiority (P for noninferiority = 0.001). Major cardiovascular events were comparable between 2 groups at 6 months (7.7% for the novel DCB vs 10.3% for the reference DCB; P = 0.692).

CONCLUSIONS

In this multicenter, head-to-head comparison randomized trial, the novel shellac plus vitamin E-based DCB showed a comparable result to the reference iopromide-based device for the primary endpoint of 6-month in-segment LLL for the treatment of coronary ISR. (Compare the Safety and Efficacy of Genoss® DCB and SeQuent® Please in Korean Patient With Coronary In-stent Restenosis; NCT04405063).

Sex-specific difference of in-hospital mortality from COVID-19 in South Korea

We sought to assess the impact of sex on in-hospital mortality of patients with COVID-19 infection in South Korea. The study recruited 5,628 prospective consecutive patients who were hospitalized in South Korea with COVID-19 infection, and enrolled in the Korea Centers for Disease Control and Prevention (KCDC) dataset between January 20, 2020, and April 30, 2020. The primary endpoint was in-hospital death from COVID-19. The cohort comprised of 3,308 women (59%) and 2,320 men (41%). In-hospital death was significantly lower in women than men (3.5% vs. 5.5%, hazard ratio (HR): 0.61; 95% confidence interval (CI): 0.47 to 0.79, p <0.001). Results were consistent after multivariable regression (HR: 0.59; 95% CI: 0.41 to 0.85, p = 0.023) and propensity score matching (HR: 0.51; 95% CI: 0.30 to 0.86, p = 0.012). In South Korea, women had a significantly lower risk of in-hospital death amongst those patients hospitalized with COVID-19 infection.

Sex-Related Outcomes of Successful Drug-Coated Balloon Treatment in De Novo Coronary Artery Disease

PURPOSE

Although drug-coated balloon (DCB) treatment is known to be effective for de novo lesions, the influence of sex on angiographic and clinical outcomes remains unknown. This study aimed to investigate the angiographic and clinical impact of DCB treatment in patients with de novo coronary lesions according to sex.

MATERIALS AND METHODS

A total of 227 patients successfully treated with DCB were retrospectively enrolled and divided into two groups according to sex. The primary endpoint was late lumen loss (LLL) at 6-month angiography, and the secondary endpoint was target vessel failure (TVF), which included cardiac death, target vessel myocardial infarction, target lesion revascularization, and target vessel thrombosis.

RESULTS

The study enrolled 60 women (26.4%) and 167 men (73.6%). Compared to men, women had a smaller vessel size, larger DCB to reference vessel ratio, and more dissections after DCB treatment (55.0% vs. 37.1%, p=0.016). Women also had a significantly higher LLL compared to men (0.12±0.26 mm vs. 0.02±0.22 mm, p=0.012) at the 6-month follow-up angiography. During a median follow-up of 3.4 years (range 12.7-28.9 months), TVF was similar (women 6.7% vs. men 7.8%, p=0.944). In multivariable analysis, women were independently associated with a higher LLL.

CONCLUSION

LLL was higher in women, but there was no difference in TVF between women and men. Based on multivariable analysis, the women sex was an independent predictor of higher LLL (Impact of Drug-coated Balloon Treatment in de Novo Coronary Lesion; NCT04619277).

Drug-coated balloon treatment for nonsmall de-novo coronary artery disease: angiographic and clinical outcomes

OBJECTIVES

Although drug-coated balloons (DCBs) are established for de-novo lesions in small coronary arteries, the impact of DCB treatment according to the reference vessel diameter (RVD) remains poorly defined. This study aimed to evaluate the angiographic and long-term clinical outcomes of DCB treatment for de-novo coronary lesions according to RVD.

METHODS AND RESULTS

A total of 227 patients were retrospectively enrolled and stratified according to an RVD >2.5 mm [nonsmall vessel disease (NSVD) group, n = 100] and ≤2.5 mm [small vessel disease (SVD) group, n = 127]. The primary endpoint was late lumen loss (LLL) at a 6-month follow-up, and the secondary endpoint was target vessel failure (TVF, a composite of cardiac death, target vessel myocardial infarction, target vessel revascularization and target vessel thrombosis). The LLL among the 206 patients (90.8%) returning for scheduled angiography at 6 month was similar (NSVD, 0.03 ± 0.22 mm vs. SVD, 0.06 ± 0.25 mm; P = 0.384). TVF was also comparable in both groups at a median follow-up of 3.4 years (NSVD, 7.0 vs. SVD, 7.9 %; P = 0.596). At baseline, there were numerically more dissections in the SVD group compared to the NSVD group (47.2 vs. 35.0 %; P = 0.064); however, most of these had disappeared in both groups at a 6-month follow-up. In a multivariable analysis, the presence of dissection was not associated with LLL or TVF in either group.

CONCLUSIONS

The safety and efficacy of DCB treatment for de-novo coronary lesions, in terms of LLL and TVF, was unrelated to RVD.

A Clinical Risk Score to Predict In-hospital Mortality from COVID-19 in South Korea

BACKGROUND

Early identification of patients with coronavirus disease 2019 (COVID-19) who are at high risk of mortality is of vital importance for appropriate clinical decision making and delivering optimal treatment. We aimed to develop and validate a clinical risk score for predicting mortality at the time of admission of patients hospitalized with COVID-19.

METHODS

Collaborating with the Korea Centers for Disease Control and Prevention (KCDC), we established a prospective consecutive cohort of 5,628 patients with confirmed COVID-19 infection who were admitted to 120 hospitals in Korea between January 20, 2020, and April 30, 2020. The cohort was randomly divided using a 7:3 ratio into a development (n = 3,940) and validation (n = 1,688) set. Clinical information and complete blood count (CBC) detected at admission were investigated using Least Absolute Shrinkage and Selection Operator (LASSO) and logistic regression to construct a predictive risk score (COVID-Mortality Score). The discriminative power of the risk model was assessed by calculating the area under the curve (AUC) of the receiver operating characteristic curves.

RESULTS

The incidence of mortality was 4.3% in both the development and validation set. A COVID-Mortality Score consisting of age, sex, body mass index, combined comorbidity, clinical symptoms, and CBC was developed. AUCs of the scoring system were 0.96 (95% confidence interval [CI], 0.85-0.91) and 0.97 (95% CI, 0.84-0.93) in the development and validation set, respectively. If the model was optimized for > 90% sensitivity, accuracies were 81.0% and 80.2% with sensitivities of 91.7% and 86.1% in the development and validation set, respectively. The optimized scoring system has been applied to the public online risk calculator (https://www.diseaseriskscore.com).

CONCLUSION

This clinically developed and validated COVID-Mortality Score, using clinical data available at the time of admission, will aid clinicians in predicting in-hospital mortality.

Impact of Dissection after Drug-Coated Balloon Treatment of De Novo Coronary Lesions: Angiographic and Clinical Outcomes

PURPOSE

Dissection after plain balloon angioplasty is required to achieve adequate luminal area; however, it is associated with a high risk of vascular events. This study aimed to examine the relationship between non-flow limiting coronary dissections and subsequent lumen loss and long-term clinical outcomes following successful drug-coated balloon (DCB) treatment of de novo coronary lesions.

MATERIALS AND METHODS

A total of 227 patients with good distal flow (Thrombolysis in Myocardial Infarction flow grade 3) following DCB treatment were retrospectively enrolled and stratified according to the presence or absence of a non-flow limiting dissection. The primary endpoint was late lumen loss (LLL) at 6-month angiography, and the secondary endpoint was target vessel failure (TVF, a composite of cardiac death, target vessel myocardial infarction, target vessel revascularization, and target vessel thrombosis).

RESULTS

The cohort consisted of 95 patients with and 132 patients without a dissection. There were no between-group differences in LLL (90.8%) returning for angiography at 6 months (0.05±0.19 mm in non-dissection and 0.05±0.30 mm in dissection group, p=0.886) or in TVF (6.8% in non-dissection and 8.4% in dissection group, p=0.799) at a median follow-up of 3.4 years. In a multivariate analysis, the presence of dissection and its severity were not associated with LLL or TVF. Almost dissections (93.9%) were completely healed, and there was no newly developed dissection at 6-month angiography.

CONCLUSION

The presence of a dissection following successful DCB treatment of a de novo coronary lesion may not be associated with an increased risk of LLL or TVF (Impact of Drug-coated Balloon Treatment in de Novo Coronary Lesion; NCT04619277).

Septal Reduction Using Transvenous Intramyocardial Cerclage Radiofrequency Ablation: Preclinical Feasibility

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Surgical myectomy is morbid and transcoronary alcohol septal ablation can result in geographic miss or occasional nontarget injury.

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We developed a transvenous intraseptal radiofrequency ablation technique (cerclage ablation method) to overcome the shortcomings of surgical myectomy and alcohol septal ablation.

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We delivered dedicated intraseptal radiofrequency ablation catheter into the ventricular septum through the coronary sinus and a septal vein. The ablated volume of myocardium was larger at higher electrode temperatures and using an irrigated-ablation mode in vitro. Cerclage ablation was successful in all in vivo attempts and induced a focal regional wall motion abnormality at later follow-up.

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This study presents in vivo evidence of the feasibility, effectiveness, and safety of cerclage ablation method to debulk interventricular septal myocardium.

Debulking of left ventricular septal mass is typically accomplished using surgical myectomy, which is morbid, or using transcoronary alcohol septal ablation, which can result in geographic miss and occasional catastrophic nontarget coronary injury. The authors developed and tested operational parameters in vitro and vivo for a device to accomplish transvenous intraseptal radiofrequency ablation to reduce ventricular septal mass using a technique derived from mitral cerclage, which the authors call cerclage ablation. Cerclage ablation appeared feasible in vitro and safe and effective in vivo. Cerclage ablation is an attractive new approach to debulk the interventricular septum in obstructive hypertrophic cardiomyopathy. These data support clinical investigation.

Provisional drug-coated balloon treatment guided by physiology on de novo coronary lesion

Although drug-eluting stents (DES) have become the mainstay of percutaneous coronary intervention, late and very late stent thrombosis remains a concern. Drug-coated balloons (DCB) have the advantage of preserving the anti-restenotic benefits of DES while minimizing potential long-term safety concerns. Currently the two methods to ensure successful DCB treatment of a stenotic lesion are angiography or physiology-guided DCB application. This review will evaluate these two methods based on previous evidence and make suggestions on how to perform DCB treatment more efficiently and safely.

In Vivo Fluorescence Microendoscopic Monitoring of Stent-Induced Fibroblast Cell Proliferation in an Esophageal Mouse Model

PURPOSE

To evaluate the feasibility of self-expanding metal stent (SEMS) placement and fluorescence microendoscopic monitoring for determination of fibroblast cell proliferation after stent placement in an esophageal mouse model.

MATERIALS AND METHODS

Twenty fibroblast-specific protein (FSP)-1 green fluorescent protein (GFP) transgenic mice were analyzed. Ten mice (Group A) underwent SEMS placement, and fluoroscopic and fluorescence microendoscopic images were obtained biweekly until 8 weeks thereafter. Ten healthy mice (Group B) were used for control esophageal values.

RESULTS

SEMS placement was technically successful in all mice. The relative average number of fibroblast GFP cells and the intensities of GFP signals in Group A were significantly higher than in Group B after stent placement. The proliferative cellular response, including granulation tissue, epithelial layer, submucosal fibrosis, and connective tissue, was increased in Group A. FSP-1-positive cells were more prominent in Group A than in Group B.

CONCLUSIONS

SEMS placement was feasible and safe in an esophageal mouse model, and proliferative cellular response caused by fibroblast cell proliferation after stent placement was longitudinally monitored using a noninvasive fluorescence microendoscopic technique. The results have implications for the understanding of proliferative cellular response after stent placement in real-life patients and provide initial insights into new clinical therapeutic strategies for restenosis.

Analysis of trends and prospects regarding stents for human blood vessels

Background

The purpose of this paper is to provide technology trends and information regarding market and prospects in stents used for human blood vessels in Korea and the world.

A stent is a medical device in the form of a cylindrical metal net used to normalize flow when blood or other bodily fluids such as biliary fluids are obstructed in blood vessels, gastrointestinal tracts, etc. by inserting the stent into a narrowed or clogged area. Stents are classified into vascular and non-vascular stents. The coronary artery stent is avascular stent that is used for coronary atherosclerosis.

The demand is increasing for stents to treat diseases such as those affecting the heart and blood vessels of elderly and middle-aged patients. Due to the current shift in the demographic structure caused by an aging society, the prospect for stents seems to be very bright.

The use of a stent designed to prevent acute vascular occlusion and restenosis, which is a side effect of conventional balloon angioplasty, has rapidly become popular because it can prevent acute complications and improve clinical outcomes. Since the initial release of this stent, there have been significant developments in its design, the most notable of which has been the introduction of drug-eluting stents (DES). Bioresorbable scaffolds (BRS) have the potential to introduce a paradigm shift in interventional cardiology, a true anatomical and functional “vascular restoration” instead of an artificial stiff tube encased by a persistent metallic foreign body.

Methods

Data for this research were gathered from primary and secondary sources as well as the databases of the Korea Institute of Science Technology Information (KISTI) located in Seoul, Korea like KISTI Market Report. The sources used for primary research included the databases available from the Korea Institute of Science Technology Information, past industry research services/studies, economic and demographic data, and trade and industry journals. Secondary research was used to supplement and complement the primary research. Interviews were conducted with physicians and surgeons from the key hospitals and senior sale/marketing managers from stent product suppliers in South Korea.

Results

The global stent market is estimated at US $ 7.98 billion in 2016 and is expected to grow at a Compound Annual Growth Rate (CAGR) of 3.8% over the next 5 years. As of 2016, the global market for vascular stents is estimated at $ 7.22 billion, with coronary artery stents accounting for 67.3% of the vascular stent market. Among the coronary artery stents, BRS is notably expected to grow at an annual average rate of 8.8% by 2020, but the global adoption rate of BRS remains low at present. In the Korean market, stents for blood vessels account for most of the market, and the market size of stents for blood vessels in Korea was estimated to be 145 billion won as of 2016.

Conclusions

In comparison to the sales growth rate of other medical devices, the future stent technology market is judged to be higher in growth potential.

Radiation-induced esophageal strictures treated with fluoroscopic balloon dilation: clinical outcomes and factors influencing recurrence in 62 patients

Background Balloon dilation is safe and effective for the treatment of radiation-induced esophageal stricture (RIES), with favorable short-term and mid-term outcomes; however, few reports of long-term outcomes exist. Few studies have evaluated factors associated with recurrence after balloon dilation. Purpose To evaluate the long-term outcome of balloon dilation in patients with RIES and to identify factors associated with stricture recurrence. Material and Methods The medical records of 62 consecutive patients who had undergone fluoroscopic balloon dilation for RIES at our institution between December 1998 and June 2016 were reviewed. Results One hundred and twenty balloon dilation sessions were performed in 62 patients (mean = 1.9 sessions per patient). Clinical success was achieved in 53 (86%) patients after single (n = 37) or multiple (n = 16) dilation sessions. Complications occurred in 27% of the dilation sessions. The primary patency rates at one, two, three, and five years were 60%, 56%, 52%, and 52%, respectively. Secondary patency rates at one, two, three, and five years were 87%, 85%, 85%, and 80%, respectively. Multivariate logistic regression analysis identified an interval from radiation therapy (RT) to stricture of ≥6 months (hazard ratio [HR] = 0.205; P < 0.001), strictures located at the cervical esophagus (HR = 5.846; P < 0.001), and stricture length of ≥2 cm (HR = 2.923; P = 0.006) as significant predictors of recurrence. Conclusion Despite the high incidence of ruptures and recurrences, fluoroscopic balloon dilation is valuable as an initial therapeutic option for patients with RIES.

3D-printed phantom study for investigating stent abutment during gastroduodenal stent placement for gastric outlet obstruction

Background

Placing a self-expandable metallic stent (SEMS) is safe and effective for the palliative treatment of malignant gastroduodenal (GD) strictures. SEMS abutment in the duodenal wall is associated with increased food impaction, resulting in higher stent malfunction and shorter stent patency. The desire to evaluate the mechanism and significance of stent abutment led us to design an in vitro experiment using a flexible anthropomorphic three-dimensional (3D)-printed GD phantom model.

Results

A GD phantom was fabricated using 3D printer data after performing computed tomography gastrography. A partially covered (PC) or fully covered (FC) stent was placed so that its distal end abutted onto the duodenal wall in groups PC-1 and FC-1 or its distal end was sufficiently directed caudally in groups PC-2 and FC-2. The elapsed times of the inflowing of three diets (liquid, soft, and solid) were measured in the GD phantom under fluoroscopic guidance. There was no significant difference in the mean elapsed times for the liquid diet among the four groups. For the soft diet, the mean elapsed times in groups PC-1 and FC-1 were longer than those in groups PC-2 and FC-2 (P = 0.018 and P < 0.001, respectively). For the solid diet, the mean elapsed time in group PC-1 was longer than that in group PC-2 (P < 0.001). The solid diet could not pass in group FC-1 due to food impaction. The mean elapsed times were significantly longer in groups FC-1 and FC-2 than in groups PC-1 and PC-2 for soft and solid diets (all P < 0.001).

Conclusions

This flexible anthropomorphic 3D-printed GD phantom study revealed that stent abutment can cause prolonged passage of soft and solid diets through the stent as well as impaction of solid diets into the stent.

EW-7197, an activin-like kinase 5 inhibitor, suppresses granulation tissue after stent placement in rat esophagus

BACKGROUND AND AIMS

Self-expanding metallic stent (SEMS) placement is a well-established method for treating malignant esophageal strictures; however, this procedure has not gained widespread acceptance for treating benign esophageal strictures because of granulation tissue formation. The aim of the present study was to investigate whether EW-7197, a novel per-oral transforming growth factor-β type I receptor kinase inhibitor, suppressed granulation tissue formation after SEMS placement in the rat esophagus.

METHODS

Sixty rats underwent SEMS placement and were randomly divided into 4 groups. Group A (n = 20) received vehicle-treated control for 4 weeks. Group B (n = 20) received 20 mg/kg/day EW-7197 for 4 weeks. Group C (n = 10) received 20 mg/kg/day EW-7197 for 4 weeks followed by vehicle-treated control for 4 weeks. Group D (n = 10) received 20 mg/kg/day EW-7197 for 8 weeks.

RESULTS

SEMS placement was technically successful in all rats. Eleven rats, however, were excluded because of stent migration (n = 9) and procedure-related death (n = 2). The luminal diameter in group A was significantly smaller than those in groups B, C, and D (all P < .001). The percentage of granulation tissue area, number of epithelial layers, thickness of submucosal fibrosis, percentage of connective tissue area, and degree of collagen deposition were significantly higher in group A than in groups B, C, and D (all P < .001); however, there were no significant differences among groups B, C, and D. EW-7197 decreased the expression levels of phospho-Smad 3, N-cadherin, fibronectin, α-smooth muscle actin, and transforming growth factor-β1 and increased the expression level of E-cadherin (all P < .01).

CONCLUSIONS

EW-7197 suppressed granulation tissue formation after SEMS placement in the rat esophagus.

Overlapping self-expandable metallic stent for palliation of a long (>10 cm) malignant gastroduodenal obstruction

Background Self-expandable metallic stent (SEMS) placement is a well-established palliative treatment approach for malignant gastroduodenal obstruction. In patients with a long (>10 cm) stricture, multiple stents placed in an overlapping fashion are often required. Purpose To investigate the outcomes of overlapping SEMS placement for the palliative treatment of malignant gastroduodenal obstruction in patients with a long (>10 cm) stricture. Material and Methods The medical records of 40 patients who underwent fluoroscopic overlapping SEMS placement for malignant gastroduodenal obstruction due to a long (>10 cm) stricture were reviewed. Results The technical and clinical success rates were 100% and 65.0%, respectively. The mean length of the stricture was 17.0 ± 4.7 cm and the mean number of stents placed in each patient was 2.2 ± 0.5. Metastatic cancer (odds ratio [OR], 0.315; P = 0.018), Eastern Cooperative Oncology Group (ECOG) score ≥3 (OR, 0.018; P = 0.006), and carcinomatosis with ascites (OR, 0.025; P = 0.017) were independent predictors of poor clinical success. The rates of minor and major complications were 27.5% and 2.5%, respectively. The median stent patency and survival were 33 days (interquartile range [IQR], 19-60 days) and 35 days (IQR, 19-73 days), respectively. An ECOG score ≥3 was an independent predictor of a poor survival outcome (hazard ratio, 4.681; P < 0.001). Conclusion Overlapping SEMS placement may be safe and effective for the palliative treatment of malignant gastroduodenal obstruction in patients with a long (>10 cm) stricture.

Fluoroscopic Balloon Dilation for Treating Postoperative Nonanastomotic Strictures in the Proximal Small Bowel: A 15-Year Single-Institution Experience

PURPOSE

To evaluate safety and effectiveness of fluoroscopic balloon dilation (FBD) for treating postoperative nonanastomotic strictures in proximal small bowel.

MATERIALS AND METHODS

Data of 44 patients (26 men and 18 women; mean age, 53.7 y ± 13.0) treated with FBD for postoperative nonanastomotic strictures in the proximal small bowel between January 2000 and February 2016 were retrospectively reviewed. Site of stricture was located in the first portion of duodenum in 8 (18.2%) patients, second portion of duodenum in 8 (18.2%) patients, third portion of duodenum in 1 (2.3%) patient, fourth portion of duodenum in 1 (2.3%) patient, and proximal jejunum in 26 (59.1%) patients. Mean distance between the most anal-side lesion and the oral cavity was 63.9 cm ± 15.0.

RESULTS

Technical success was achieved in 39 (88.6%) patients. Mean stricture length was 3.0 cm ± 1.8. Technical failure because of inability to negotiate the guide wire through the stricture occurred in 5 (13.6%) patients. Complete resolution of obstructive symptoms and resumption of oral intake of soft or solid food within 3 days occurred in 34 patients after 1 (n = 32) or 2 (n = 2) FBD sessions, rendering a clinical success rate of 87.2%. There were no major complications directly related to FBD. Median follow-up period was 1,406 days (interquartile range, 594-2,236 d). Nine (26.5%) patients had recurrence within a median 47 days (interquartile range, 20-212 d).

CONCLUSIONS

FBD may be safe and effective for treating postoperative nonanastomotic strictures in the proximal small bowel.

Fluoroscopic removal of retrievable self-expandable metal stents in patients with malignant oesophageal strictures: Experience with a non-endoscopic removal system

OBJECTIVES

To evaluate clinical outcomes of fluoroscopic removal of retrievable self-expandable metal stents (SEMSs) for malignant oesophageal strictures, to compare clinical outcomes of three different removal techniques, and to identify predictive factors of successful removal by the standard technique (primary technical success).

METHODS

A total of 137 stents were removed from 128 patients with malignant oesophageal strictures. Primary overall technical success and removal-related complications were evaluated. Logistic regression models were constructed to identify predictive factors of primary technical success.

RESULTS

Primary technical success rate was 78.8 % (108/137). Complications occurred in six (4.4 %) cases. Stent location in the upper oesophagus (P=0.004), stricture length over 8 cm (P=0.030), and proximal granulation tissue (P<0.001) were negative predictive factors of primary technical success. If granulation tissue was present at the proximal end, eversion technique was more frequently required (P=0.002).

CONCLUSIONS

Fluoroscopic removal of retrievable SEMSs for malignant oesophageal strictures using three different removal techniques appeared to be safe and easy. The standard technique is safe and effective in the majority of patients. The presence of proximal granulation tissue, stent location in the upper oesophagus, and stricture length over 8 cm were negative predictive factors for primary technical success by standard extraction and may require a modified removal technique.

KEY POINTS

• Fluoroscopic retrievable SEMS removal is safe and effective. • Standard removal technique by traction is effective in the majority of patients. • Three negative predictive factors of primary technical success were identified. • Caution should be exercised during the removal in those situations. • Eversion technique is effective in cases of proximal granulation tissue.

The Usefulness of a Novel Screening Kit for Colorectal Cancer Using the Immunochromatographic Fecal Tumor M2 Pyruvate Kinase Test

Background/Aims

M2 pyruvate kinase (M2-PK) is an enzyme that is produced in undifferentiated and proliferating tissues. This study aims to evaluate the usefulness of the immunochromatographic M2 pyruvate kinase (iM2-PK) for the screening of colorectal cancer (CRC) and premalignant lesions.

Methods

Healthy volunteers and patients with colorectal neoplasia were enrolled in six academic hospitals in the capital province of Korea. The iM2-PK value was compared with the immunochromatographic fecal occult blood test (iFOBT) and fecal tumor M2-PK enzyme-linked immunosorbent assay (ELISA).

Results

A total of 323 subjects were enrolled. The sensitivity of iM2-PK for CRC was 92.8%, which was superior to iFOBT (47.5%, p<0.0001). For adenomatous lesions, the sensitivity of iM2-PK was 69.4%, which was also superior to iFOBT (12.1%, p<0.001). Compared with M2-PK ELISA, iM2-PK exhibited significantly enhanced sensitivity for CRC (97.5% vs 80.0%, p=0.0289). The sensitivity of iM2-PK was higher in advanced stages of CRC compared with cancers confined to the mucosa and submucosa (p<0.05). However, lymph node metastasis had no influence on the sensitivity of iM2-PK.

Conclusions

The iM2-PK exhibited increased sensitivity for identifying CRC and adenomatous lesions compared with iFOBT. Given its rapid results and convenience, CRC screening using iM2-PK is promising.

Concomitant therapy achieved the best eradication rate for Helicobacter pylori among various treatment strategies

AIM: To compare the Helicobacter pylori (H. pylori) eradication rate of clarithromycin-based triple therapy, metronidazole-based triple therapy, sequential therapy and concomitant therapy.

METHODS: A total of 680 patients infected with H. pylori were divided into 4 groups and each group was treated with a different eradication therapy. Clarithromycin-based triple therapy was applied to the first group [rabeprazole, amoxicillin and clarithromycin (PAC) group: proton pump inhibitor (PPI), amoxicillin, clarithromycin], whereas the second group was treated with metronidazole-based triple therapy [rabeprazole, amoxicillin and metronidazole (PAM) group: PPI, amoxicillin, metronidazole]. The third group was treated with rabeprazole and amoxicillin, followed by rabeprazole, clarithromycin and metronidazole (sequential group). The final group was simultaneously treated with rabeprazole, amoxicillin clarithromycin and metronidazole (concomitant therapy group). In the case of a failure to eradicate H. pylori, second-line quadruple and third-line eradication therapies were administered.

RESULTS: The per protocol (PP) analysis was performed on 143, 139, 141 and 143 patients in the PAC, PAM, sequential and concomitant groups, respectively. We excluded patients who did not receive a C¹³-urea breath test (22, 20, 23 and 22 patients, respectively) and patients with less than an 80% compliance level (5, 11, 6 and 5 patients, respectively). The eradication rates were 76.2% (109/143) in the PAC group, 84.2% (117/139) in the PAM group, 84.4% (119/141) in the sequential group and 94.4% (135/143) in the concomitant group (P = 0.0002). All 14 patients who failed second-line therapy were treated with third-line eradication therapy. Among these 14 patients, 6 infections were successfully eradicated with the third-line therapy. Both PP and intention-to-treat analysis showed an eradication rate of 42.9% (6/14). In the PAC group, 3 of 4 patients were successfully cured (3/4, 75%); 2 of 2 patients in the PAM group (2/2, 100%) and 1 of 5 patients in the sequential group (1/5, 20%) were also cured. In the concomitant group, all 3 patients failed (0/3, 0%).

CONCLUSION: The eradication rate for the concomitant therapy was much higher than those of the standard triple therapy or sequential therapy (ClinicalTrials.gov number NCT01922765).

Polydioxanone biodegradable stent placement in a canine urethral model: analysis of inflammatory reaction and biodegradation

PURPOSE

To investigate the inflammatory reaction and perform quantitative analysis of biodegradation after placement of a polydioxanone (PDO) biodegradable stent in a canine urethral model.

MATERIALS AND METHODS

PDO biodegradable stents were placed in the proximal and distal urethra of nine male mongrel dogs. The dogs were euthanized 4 weeks (group A; n = 3), 8 weeks (group B; n = 3), or 12 weeks (group C; n = 3) after stent placement. The luminal diameter of the stent-implanted urethra was assessed by follow-up retrograde urethrography, and histologic findings were obtained after the dogs were killed. Stents were removed after euthanasia, and their surface morphology and molecular weight were evaluated. Hematologic examination was performed to evaluate inflammatory reaction.

RESULTS

Stent placement was technically successful in all dogs. The average luminal diameter gradually decreased. The average number of epithelial layers (2.93 vs 4.42; P < .001), the average thickness of papillary projection (0.80 mm vs 1.28 mm; P < .001), and the average thickness of submucosal fibrosis (0.34 mm vs 0.49 mm ; P < .001) were significantly increased in group B versus group A. There were no significant differences between group B and group C. The average inflammatory cell infiltration did not differ significantly in the three groups. Molecular weight losses were 54% in group A and 84% in group B. In group C, PDO stents were completely decomposed.

CONCLUSIONS

An experimental study in a canine urethral model has demonstrated acceptable inflammatory reaction with gradually increasing granulation tissue but no luminal obstruction within 12 weeks.

Cataracts among adults aged 30 to 49 years: a 10-year study from 1995 to 2004 in Korea

Purpose

To investigate the long-term characteristics of cataracts among adults aged 30 to 49 years in Korean over a span of 10 years.

Methods

Subjects between the ages of 30 to 49 years who underwent cataract surgery at St. Mary's Hospital from 1995 to 2004 (n = 976) were included. Patients with a history of ocular trauma, uveitis, other ocular or systemic diseases, and congenital cataracts were excluded. Additional information including type of lens opacity, urban/rural region, and pre- and postoperative visual acuities were analyzed. Lens opacity grading was conducted using Lens Opacity Classification System III. The Cochran-Armitage proportion trend test was used to analyze vision changes with the passage of time.

Results

Among the patients who had undergone cataract surgeries, 8.8% (976 / 11,111) met the inclusion criteria. The mean age was 41.7 ± 5.45 years. Gender breakdown of the patient population included 79.0% male and 21.0% female. In terms of home environment, 60.9% were from an urban region and 39.1% from a rural region. Opacity type included anterior polar (AP), posterior subcapsular (PSC), AP and PSC, cortical, and nuclear in 35.7%, 35.1%, 7.0%, 6.0%, and 5.4% of patients, respectively. At a 2-month postoperative follow-up appointment, 92.7% of patients showed a best-corrected visual acuity of more than 20 / 40.

Conclusions

Predominance of AP and PSC opacities as well as male patients was observed in this study population.

Eradication of Helicobacter pylori according to 23S ribosomal RNA point mutations associated with clarithromycin resistance

BACKGROUND

Clarithromycin-resistant Helicobacter pylori is associated with point mutations in the 23S ribosomal RNA (rRNA) gene.

METHODS

A total of 1232 patients participated and were divided into 2 control groups and 1 case group. Patients in the APC control group, which consisted of 308 randomly assigned participants, were treated with standard triple therapy, consisting of amoxicillin, rabeprazole, and clarithromycin; 308 participants in the APM control group were treated with amoxicillin, rabeprazole, and metronidazole. For the 616 participants in the case group, a test for point mutations in the 23S rRNA gene of H. pylori was conducted. A total of 218 individuals in the case group received a new tailored therapy regimen, in which amoxicillin, rabeprazole, and clarithromycin were given in the absence of a mutation, whereas clarithromycin was replaced by metronidazole if the mutation was detected.

RESULTS

The rate of eradication of H. pylori in the tailored group was 91.2% (176/193), which was significantly higher than that in the APC (75.9% [214/282]; P < .001) and APM (79.1% [219/277]; P < .001) control groups.

CONCLUSION

The rate of H. pylori eradication among patients who received tailored therapy on the basis of detection of a clarithromycin resistance mutation by polymerase chain reaction was much higher than the rate among patients who received a standard triple therapy regimen.

CLINICAL TRIALS REGISTRATION

NCT0145303.

Antiviral protection against enterovirus 71 mediated by autophagy induction following FLICE-inhibitory protein inactivation

Even with the recent awareness of enterovirus 71 (EV71) as a major public health issue, there are no preventive or therapeutic agents that are effective against EV71 infection. Although FLICE-like inhibitory protein (FLIP) has been identified as a factor that modulates virus pathogenesis, there are no reports regarding its effects on EV71 infection. The aim of the present study was to identify whether FLIP influences EV71 pathogenesis and to understand the underlying mechanisms. Virus replication was markedly reduced in MRC5 cells preincubated with anti-FLIP peptides, and infected cells were rescued from the cytopathic effects of the virus. The anti-FLIP peptides induced autophagy by disrupting intrinsic FLIP functions. The antiviral activity of these peptides was reduced when autophagy was inhibited by treatment with siRNA targeted to beclin-1. Thus, the present study provides evidence that anti-FLIP peptides induce autophagy by inactivating cFLIP, and that this is associated with antiviral effects against EV71.

Comparison of bursting pressure after scleral tunnel incision sealed with sutures or an adherent ocular bandage in human globes

OBJECTIVE

To evaluate the efficiency of a hydrogel adherent ocular bandage for sealing of scleral tunnel incisions in human eye globes.

METHODS

A 4-mm scleral tunnel incision was made in each of 10 globes and bursting pressure was measured using the Seidel test to check for wound leakage. Globes were sealed using either two interrupted 10-0 nylon sutures (n = 5) or an adherent ocular bandage in the form of polyethylene glycol hydrogel (n = 5). Bursting pressure was then measured for a second time.

RESULTS

Bursting pressure was significantly higher after wound sealing in both groups. There were no statistically significant differences in bursting pressure between the two groups before or after sealing.

CONCLUSIONS

The adherent ocular bandage successfully protected the incision in ex vivo human globes immediately after surgery, with a sealing efficiency comparable to two nylon sutures, suggesting that it is a safe and effective alternative to conventional suturing.

Characterization of infections of human leukocytes by non-polio enteroviruses

To elucidate the detailed susceptibilities of leukocytes to clinically important non-polio enteroviruses (EVs), primary monocytes and various human leukocyte cell lines were infected with coxsackievirus A24 (CVA24), coxsackievirus B3 (CVB3), and enterovirus 70 (EV70). The permissiveness was then assessed by determining virus replication and resultant cytopathic effects. Different EVs varied markedly in their ability to infect leukocyte cell lines. CVB3 replicated effectively in leukocytes of B-cell, T-cell, and monocyte origin, CVA24 in leukocytes of B-cell and monocyte origin, and EV70 in leukocytes of monocyte origin. Primary monocytes, as well as monocyte-derived U-937 cells, were permissive to all three EVs. We observed a positive correlation between cytotoxicity and active virus replication, except in CVB3-infected monocytes. U-937 cells efficiently generated CVB3 progeny virus without severe cellular damage, including cell death. Moreover, infectivity on leukocytes was not absolutely associated with the availability of viral receptors. These findings suggest that the susceptibility of human leukocytes to non-polio EVs may be responsible for virus transport during the viremic phase, particularly to secondary target organs, and that active replication of CVB3 in all human leukocyte lineages leads to greater dissemination, in agreement with the ability of CVB to cause systemic diseases.

Selenium deficiency contributes to the chronic myocarditis in coxsackievirus-infected mice

Both coxsackievirus B3 (CVB3) infection and selenium (Se) deficiency play a pivotal role in Keshan disease of the heart. The Se deficiency was known to contribute to the CVB3-induced myocarditis in acute and subacute phase of infection. However, its effect on the myocarditis in chronic phase of infection has not been examined yet. To address this question, we kept mice on a Se-replete or Se-deficient diet for 28 days, infected them intraperitoneally with CVB3 and maintaining previous diets, we examined them for next 90 days for several parameters indicative of the infection or disease. We found out that the mice on the Se-deficient diet exhibited a higher mortality, lower serum glutathione peroxidase (GPx) activity, evident histopathological changes indicative of myocarditis, and a higher level of viral RNA in the heart. Summing up, these data suggest that the Se-deficiency creates a chronic myocarditis-prone condition by fostering the active virus replication.

An antiviral small-interfering RNA simultaneously effective against the most prevalent enteroviruses causing acute hemorrhagic conjunctivitis

PURPOSE

Acute hemorrhagic conjunctivitis (AHC), a highly contagious eye disease, is caused primarily by either enterovirus 70 (EV70) or coxsackievirus A24 (CVA24) infection. Yet methods to prevent or cure AHC are not available. Recent evidence has shown that small-interfering RNAs (siRNAs), mediators of posttranscriptional gene knockdown, can act as effective antiviral agents. Thus, the authors attempted to develop a novel siRNA-based anti-AHC agent effective against both EV70 and CVA24.

METHODS

Concurrent screening of the entire viral genome sequences of EV70 and CVA24 using the CAPSID program identified five different siRNA candidates complementary to genome regions of both viruses. The antiviral potentials of these siRNAs were assessed by treating MRC5 and primary human conjunctival cells with the siRNAs and following this with viral challenge.

RESULTS

Among the five siRNAs, AHCe-3D-3 siRNA showed excellent cytoprotective effects and dramatic decreases in virus replication and virus protein synthesis. This siRNA, targeting the virus polymerase 3D gene, also induced similar antiviral effects in primary human conjunctival cells.

CONCLUSIONS

These findings strongly suggest that the AHCe-3D-3 siRNA, homologous to two different AHC-associated enteroviruses, can provide equivalent antiviral activities against both AHC-causing enteroviruses. Such an siRNA may be developed as a clinically valuable AHC control agent.

Melanosis ilei induced by prolonged charcoal ingestion

Gastrointestinal melanosis is observed most frequently in the colon it also can develop in the ileum, duodenum and esophagus very rarely. Melanosis ilei was thought that causative materials such as aluminum, magnesium, silicate, titanium and other compounds entered the body through the ingestion of agents. We experienced a case of melanosis in the terminal ileum that a 65-year-old female patient ingested 10 g edible charcoal everyday for 3 years to address symptoms of chronic abdominal pain. In Korea, edible charcoal has been considered to be an effective folk remedy for patients with diarrhea or chronic abdominal pain. In our case, a follow up colonoscopy was performed 3.5 years after the termination of the ingestion of edible charcoal, at which point pigmentation was faded color intensity. In conclusion, it is thought that melanosis ilei is a rare disease by ingestion of causative materials and is discontinuous, local and reversible disease.

[Remission of ulcerative colitis after appendectomy: a case report]

The inverse correlation of appendectomy and ulcerative colitis is well known, but the effect of appendectomy on the clinical course of ulcerative colitis remains unclear. Although the majority of opinions were negative for the therapeutic advantage of appendectomy in patients with ulcerative colitis, advocates for positive effect of appendectomy have been proposed in a few case reports and a prospective study from Western countries. We herein report a case of ulcerative colitis who experienced clinical remission after appendectomy for acute appendicitis. The patient was 35 year old male and had been managed with immunosuppressant before appendectomy. The very acute change in clinical course and a long period of remission after appendectomy highly suggest the therapeutic effect of appendectomy for ulcerative colitis.

Toxic anterior segment syndrome after cataract surgery

We report a case of toxic anterior segment syndrome (TASS) that developed after cataract surgery. A 78-year-old woman had uneventful phacoemulsification via a clear corneal incision with implantation of an acrylic intraocular lens. One day postoperatively, diffuse corneal edema and anterior chamber inflammation were evident. Topical antibiotic and steroid eyedrops were prescribed. The anterior chamber reaction decreased considerably, but corneal edema persisted. After a thorough investigation, the antiseptic solution used to soak surgical instruments before subsequent surgery was identified as the source of the problem.

A novel program to design siRNAs simultaneously effective to highly variable virus genomes

A major concern of antiviral therapy using small interfering RNAs (siRNAs) targeting RNA viral genome is high sequence diversity and mutation rate due to genetic instability. To overcome this problem, it is indispensable to design siRNAs targeting highly conserved regions. We thus designed CAPSID (Convenient Application Program for siRNA Design), a novel bioinformatics program to identify siRNAs targeting highly conserved regions within RNA viral genomes. From a set of input RNAs of diverse sequences, CAPSID rapidly searches conserved patterns and suggests highly potent siRNA candidates in a hierarchical manner. To validate the usefulness of this novel program, we investigated the antiviral potency of universal siRNA for various Human enterovirus B (HEB) serotypes. Assessment of antiviral efficacy using Hela cells, clearly demonstrates that HEB-specific siRNAs exhibit protective effects against all HEBs examined. These findings strongly indicate that CAPSID can be applied to select universal antiviral siRNAs against highly divergent viral genomes.

Antiviral potency of a siRNA targeting a conserved region of coxsackievirus A24

Coxsackievirus A24 (CVA24) is responsible for acute hemorrhagic conjunctivitis, a highly contagious eye disease for which no prevention or treatment is currently available. We thus assessed the antiviral potential of a small interfering RNA (siRNA) targeting CVA24. HeLa cells with or without four different siRNAs complementary to 2C or 3D genome region, were challenged with various CVA24s. Among several siRNAs, a siRNA targeting the highly conserved genome region called the cis-acting replication element (CVA24-CRE), was the only siRNA that decreased virus replication and subsequent cytotoxicity by both CVA24 variant and clinical isolates. Furthermore, CVA24-CRE had effective antiviral activity against CVA24 in primary human conjunctival cells. In addition, CVA24-CRE was highly resistant to the emergence of genetically altered escape mutants. Collectively, the present study provides evidence that CVA24-CRE targeting a conserved viral genome region had universal, prolonged anti-CVA24 activity. This siRNA may thus hold a potential to act clinically as a novel anti-CVA24 agent.

Role of HGF/c-Met in serum-starved ARPE-19 cells

Purpose

Hepatocyte growth factor (HGF) and its receptor (HGFR/c-Met) regulate motility, mitogenesis, and morphogenesis in a cell type-dependent fashion. We report the role of HGF and c-Met on stress-induced ARPE-19 human retinal pigment epithelial (RPE) cells in this study.

Methods

The cells were cultured either with or without serum. Southern and Western blot analyses were done to determine the expression patterns of HGF/c-Met in serum-starved ARPE-19 cells. The cell proliferation pattern in serum-starved condition was analyzed using MTS assay. Inhibition level of cell proliferation was analyzed using a neutralizing monoclonal antibody against c-Met (2 µg/ml).

Results

Abnormal cell proliferation and scattering of ARPE-19 cells was observed under serum starvation. HGF/c-Met were expressed in serum-starved ARPE-19 cells. ARPE-19 cell proliferation was also enhanced with recombinant HGF treatment. Neutralization against c-Met inhibited the proliferation of serum-deprived ARPE-19 by 64.5% (n=9, S.D. 5.5%). Serum starvation appears to induce epithelial-mesenchymal transition of ARPE-19 cells, resulting in scatter, and the expression of α-smooth muscle actin (α-SMA), a marker for fibrosis.

Conclusions

In conclusion, c-Met induced under non-physiologic conditions has significant effects on the activation of RPE cells.

Mutation variants generated from nonvirulent coxsackievirus B3 acquire virulence phenotypes by active virus replication

OBJECTIVE

To understand coxsackievirus B3 (CVB3) virulence at the molecular level.

METHOD

A mutation library was generated from noncardiovirulent CVB3/0. Highly virulent mutation variants were recovered and characterized both phenotypically and genotypically.

RESULTS

The variants consistently caused destruction of multiple tissues together with active virus production and induced severe mortality in vivo. The extent of infectious virus generation was directly correlated with that of histopathological aberration. Genotypic analysis of the entire genome indicated that the virulent viruses encode nucleotide substitutions in the 5'-nontranslated region, which have previously been identified in other virulent CVB3s.

CONCLUSION

The present study provides evidence that particular nucleotide substitutions in the 5'-nontranslated region of nonvirulent CVB3 can lead to active virus replication, which is sufficient to induce virulence.

[Clinical significances of serum soluble fas and soluble fas ligand in chronic hepatitis B]

BACKGROUND/AIMS

Apoptosis via Fas/FasL system is thought to be involved in the development of hepatocyte death in viral hepatitis B. In chronic hepatitis C, sFas/sFasL system was reported to control liver injury induced by Fas/FasL mediated apoptosis. To determine the role of sFas/sFasL system in chronic hepatitis B, we analyzed serum sFas/sFasL in 58 HBV patients and 29 healthy controls.

METHODS

HBV patients were categorized into two groups; normal ALT (< or =40 IU/L) and elevated ALT (>40 IU/L). Serum sFas/sFasL levels in HBV patients were measured by ELISA and was compared with those in 29 healthy controls. Serum ALT levels, histological activity, and Fas/FasL expression of liver were compared.

RESULTS

Chronic hepatitis B patients with elevated ALT had significantly higher serum sFas levels than those in healthy controls (P<0.01). Serum sFasL levels, however, were significantly lower than those in healthy controls (P<0.01). Patients with moderate to marked degree of inflammation and fibrosis had significantly higher serum sFas levels than those in healthy controls (P<0.05). Serum sFasL levels had no correlation with the hepatic histological activity. Serum sFas/sFasL levels also had no significant correlation with the Fas/FasL expression of liver.

CONCLUSIONS

Serum sFas/sFasL levels play a possible role in the pathogenesis of chronic hepatitis B. These results suggest that serum sFas levels might serve as a marker for estimating the degree of hepatic histological activity.