Enhanced Postsurgical Cancer Treatment Using Methacrylated Glycol Chitosan Hydrogel for Sustained DNA/Doxorubicin Delivery and Immunotherapy

Background: Cancer recurrence and metastasis are major contributors to treatment failure following tumor resection surgery. We developed a novel implantable drug delivery system utilizing glycol chitosan to address these issues. Glycol chitosan is a natural adjuvant, inducing dendritic cell activation to promote T helper 1 cell immune responses, macrophage activation, and cytokine production. Effective antigen production by dendritic cells initiates T-cell-mediated immune responses, aiding tumor growth control. Methods: In this study, we fabricated multifunctional methacrylated glycol chitosan (MGC) hydrogels with extended release of DNA/doxorubicin (DOX) complex for cancer immunotherapy. We constructed the resection model of breast cancer to verify the anticancer effects of MGC hydrogel with DNA/DOX complex. Results: This study demonstrated the potential of MGC hydrogel with extended release of DNA/DOX complex for local and efficient cancer therapy. The MGC hydrogel was implanted directly into the surgical site after tumor resection, activating tumor-related immune cells both locally and over a prolonged period of time through immune-reactive molecules. Conclusions: The MGC hydrogel effectively suppressed tumor recurrence and metastasis while enhancing immunotherapeutic efficacy and minimizing side effects. This biomaterial-based drug delivery system, combined with cancer immunotherapy, can substantial improve treatment outcomes and patient prognosis.

Biofunctional Inorganic Layered Double Hydroxide Nanohybrid Enhances Immunotherapeutic Effect on Atopic Dermatitis Treatment

Atopic dermatitis (AD) is a widespread, recurrent, and chronic inflammatory skin condition that imposes a major burden on patients. Conventional treatments, such as corticosteroids, are associated with various side effects, underscoring the need for innovative therapeutic approaches. In this study, the possibility of using indole-3-acetic acid-loaded layered double hydroxides (IAA-LDHs) is evaluated as a novel treatment for AD. IAA is an auxin-class plant hormone with antioxidant and anti-inflammatory effects. Following the synthesis of IAA-LDH nanohybrids, their ability to induce M2-like macrophage polarization in macrophages obtained from mouse bone marrow is assessed. The antioxidant activity of IAA-LDH is quantified by assessing the decrease in intracellular reactive oxygen species levels. The anti-inflammatory and anti-atopic characteristics of IAA-LDH are evaluated in a mouse model of AD by examining the cutaneous tissues, immunological organs, and cells. The findings suggest that IAA-LDH has great therapeutic potential as a candidate for AD treatment based on its in vitro and in vivo modulation of AD immunology, enhancement of macrophage polarization, and antioxidant activity. This inorganic drug delivery technology represents a promising new avenue for the development of safe and effective AD treatments.

Uniform Gold Nanostructure Formation via Weakly Adsorbed Gold Films and Thermal Annealing for Reliable Localized Surface Plasmon Resonance-Based Detection of DNase-I

Deoxyribonuclease-I (DNase-I), a representative endonuclease, is an important biomarker for the diagnosis of infectious diseases and cancer progression. However, enzymatic activity decreases rapidly ex vivo, which highlights the need for precise on-site detection of DNase-I. Here, a localized surface plasmon resonance (LSPR) biosensor that enables the simple and rapid detection of DNase-I is reported. Moreover, a novel technique named electrochemical deposition and mild thermal annealing (EDMIT) is applied to overcome signal variations. By taking advantage of the low adhesion of gold clusters on indium tin oxide substrates, both the uniformity and sphericity of gold nanoparticles are increased under mild thermal annealing conditions via coalescence and Ostwald ripening. This ultimately results in an approximately 15-fold decrease in LSPR signal variations. The linear range of the fabricated sensor is 20-1000 ng mL-1 with a limit of detection (LOD) of 127.25 pg mL-1 , as demonstrated by spectral absorbance analyses. The fabricated LSPR sensor stably measured DNase-I concentrations from samples collected from both an inflammatory bowel disease (IBD) mouse model, as well as human patients with severe COVID-19 symptoms. Therefore, the proposed LSPR sensor fabricated via the EDMIT method can be used for early diagnosis of other infectious diseases.

Biofunctional Layered Double Hydroxide Nanohybrids for Cancer Therapy

Layered double hydroxides (LDHs) with two-dimensional nanostructure are inorganic materials that have attractive advantages such as biocompatibility, facile preparation, and high drug loading capacity for therapeutic bioapplications. Since the intercalation chemistry of DNA molecules into the LDH materials were reported, various LDH nanohybrids have been developed for biomedical drug delivery system. For these reasons, LDHs hybridized with numerous therapeutic agents have a significant role in cancer imaging and therapy with targeting functions. In this review, we summarized the recent advances in the preparation of LDH nanohybrids for cancer therapeutic strategies including gene therapy, chemotherapy, immunotherapy, and combination therapy.

Cabozantinib-Loaded PLGA Nanoparticles: A Potential Adjuvant Strategy for Surgically Resected High-Risk Non-Metastatic Renal Cell Carcinoma

Patients with high-risk non-metastatic renal cell carcinoma (RCC) are at risk of metastatic relapse following nephrectomy. Cabozantinib (CZ), a potent multitarget tyrosine kinase inhibitor, interferes with angiogenesis and immunosuppression associated with surgery-induced metastasis. Here, we explored the therapeutic potential of CZ-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (CZ-PLGA-NPs) as an adjuvant strategy for targeting post-nephrectomy metastasis. A clinically relevant subline recapitulating post-nephrectomy lung metastasis of high-risk human RCC, namely Renca-SRLu5-Luc, was established through in vivo serial selection of luciferase-expressing murine RCC Renca-Luc cells. CZ was encapsulated into PLGA-NPs via the conventional single emulsion technique. The multifaceted preclinical antimetastatic efficacy of CZ-PLGA-NPs was assessed in Renca-SRLu5-Luc cells. CZ-PLGA-NPs with a smooth surface displayed desirable physicochemical properties, good CZ encapsulation efficiency, as well as controlled and sustained CZ release. CZ-PLGA-NPs exhibited remarkable dose-dependent toxicity against Renca-SRLu5-Luc cells by inducing G2/M cell cycle arrest and apoptosis. CZ-PLGA-NPs attenuated in vitro colony formation, migration, and invasion by abrogating AKT and ERK1/2 activation. An intravenous injection of CZ-PLGA-NPs markedly reduced lung metastatic burden and prolonged lifespan with favorable safety in the Renca-SRLu5-Luc experimental lung metastasis model. The novel CZ-PLGA-NPs system with multifaceted antimetastatic effects and alleviating off-target toxicity potential is a promising adjunctive agent for patients with surgically resected high-risk RCC.

Long-acting nanoparticulate DNase-1 for effective suppression of SARS-CoV-2-mediated neutrophil activities and cytokine storm

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a new strain of coronavirus not previously identified in humans. Globally, the number of confirmed cases and mortality rates of coronavirus disease 2019 (COVID-19) have risen dramatically. Currently, there are no FDA-approved antiviral drugs and there is an urgency to develop treatment strategies that can effectively suppress SARS-CoV-2-mediated cytokine storms, acute respiratory distress syndrome (ARDS), and sepsis. As symptoms progress in patients with SARS-CoV-2 sepsis, elevated amounts of cell-free DNA (cfDNA) are produced, which in turn induce multiple organ failure in these patients. Furthermore, plasma levels of DNase-1 are markedly reduced in SARS-CoV-2 sepsis patients. In this study, we generated recombinant DNase-1-coated polydopamine-poly(ethylene glycol) nanoparticulates (named long-acting DNase-1), and hypothesized that exogenous administration of long-acting DNase-1 may suppress SARS-CoV-2-mediated neutrophil activities and the cytokine storm. Our findings suggest that exogenously administered long-acting nanoparticulate DNase-1 can effectively reduce cfDNA levels and neutrophil activities and may be used as a potential therapeutic intervention for life-threatening SARS-CoV-2-mediated illnesses.

Bioinspired DNase-I-Coated Melanin-Like Nanospheres for Modulation of Infection-Associated NETosis Dysregulation

The current outbreak of the beta-coronavirus (beta-Cov) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) began in December 2019. No specific antiviral treatments or vaccines are currently available. A recent study has reported that coronavirus disease 2019 (COVID-19), the disease caused by SARS-CoV-2 infection, is associated with neutrophil-specific plasma membrane rupture, and release excessive neutrophil extracellular traps (NETs) and extracellular DNAs (eDNAs). This mechanism involves the activation of NETosis, a neutrophil-specific programmed cell death, which is believed to play a crucial role in COVID-19 pathogenesis. Further progression of the disease can cause uncontrolled inflammation, leading to the initiation of cytokine storms, acute respiratory distress syndrome (ARDS), and sepsis. Herein, it is reported that DNase-I-coated melanin-like nanospheres (DNase-I pMNSs) mitigate sepsis-associated NETosis dysregulation, thereby preventing further progression of the disease. Recombinant DNase-I and poly(ethylene glycol) (PEG) are used as coatings to promote the lengthy circulation and dissolution of NET structure. The data indicate that the application of bioinspired DNase-I pMNSs reduce neutrophil counts and NETosis-related factors in the plasma of SARS-CoV-2 sepsis patients, alleviates systemic inflammation, and attenuates mortality in a septic mouse model. Altogether, the findings suggest that these nanoparticles have potential applications in the treatment of SARS-CoV-2-related illnesses and other beta-CoV-related diseases.

Changes of Neurotransmitters in Youth with Internet and Smartphone Addiction: A Comparison with Healthy Controls and Changes after Cognitive Behavioral Therapy

BACKGROUND AND PURPOSE

Neurotransmitter changes in youth addicted to the Internet and smartphone were compared with normal controls and in subjects after cognitive behavioral therapy. In addition, the correlations between neurotransmitters and affective factors were investigated.

MATERIALS AND METHODS

Nineteen young people with Internet and smartphone addiction and 19 sex- and age-matched healthy controls (male/female ratio, 9:10; mean age, 15.47 ± 3.06 years) were included. Twelve teenagers with Internet and smartphone addiction (male/female ratio, 8:4; mean age, 14.99 ± 1.95 years) participated in 9 weeks of cognitive behavioral therapy. Meshcher-Garwood point-resolved spectroscopy was used to measure γ-aminobutyric acid and Glx levels in the anterior cingulate cortex. The γ-aminobutyric acid and Glx levels in the addicted group were compared with those in controls and after cognitive behavioral therapy. The γ-aminobutyric acid and Glx levels correlated with clinical scales of Internet and smartphone addiction, impulsiveness, depression, anxiety, insomnia, and sleep quality.

RESULTS

Brain parenchymal and gray matter volume-adjusted γ-aminobutyric acid-to-creatine ratios were higher in subjects with Internet and smartphone addiction (P = .028 and .016). After therapy, brain parenchymal- and gray matter volume-adjusted γ-aminobutyric acid-to-creatine ratios were decreased (P = .034 and .026). The Glx level was not statistically significant in subjects with Internet and smartphone addiction compared with controls and posttherapy status. Brain parenchymal- and gray matter volume-adjusted γ-aminobutyric acid-to-creatine ratios correlated with clinical scales of Internet and smartphone addictions, depression, and anxiety. Glx/Cr was negatively correlated with insomnia and sleep quality scales.

CONCLUSIONS

The high γ-aminobutyric acid levels and disrupted balance of γ-aminobutyric acid-to-Glx including glutamate in the anterior cingulate cortex may contribute to understanding the pathophysiology and treatment of Internet and smartphone addiction and associated comorbidities.

P2497Exercise training could reduce inflammatory activity of visceral adipose tissue in overweight women

Objectives

Visceral adipose tissue (VAT) plays pivotal roles for an increased risk of cardiometabolic disease through triggering inflammatory process. This prospective study aimed to evaluate whether the exercise training could reduce inflammatory activity of VAT assessed by 18F-fluorodeoxyglucoase (FDG) positron emission tomography-computerized tomography (PET/CT).

Methods

Twenty-three overweight women who participated in exercise training program were included. Exercise training program was composed of aerobic exercise (45 min/session, 300 Kcal/day) and muscle strength training (20 min/session, 100 Kcal/day) 5 times per week for 3 months. They underwent F-18 FDG PET/CT before starting exercise program (baseline) and after completion of 3 months exercise program. Anthropometric data, clinical laboratory data, VAT area, and maximum standardized uptake value (SUVmax) of VAT were compared between baseline and after completion of the total exercise program.

Results

Baseline VAT SUVmax showed significant correlation with body weight, body mass index (BMI), waist circumference, and hip circumference. VAT SUVmax was significantly reduced by exercise training program. Exercise training program also reduced body weight, BMI, waist circumference, hip circumference, VAT area, subcutaneous adipose tissue area and blood pressure. The change of VAT SUVmax was significantly higher than the change of VAT area.

Conclusions

Exercise training could reduce the inflammatory activity of VAT assessed by F-18 FDG PET/CT. Thus, exercise would be a promising non-pharmacological strategy to reduce inflammatory activity of VAT. Furthermore, F-18 FDG PET/CT could be useful to evaluate the effect of therapeutic intervention targeted to inflammatory VAT activity.

P1249Prognostic impact of sarcopenia on major adverse cardiovascular outcomes in coronary artery disease patients undergoing successful percutaneous coronary intervention

Background

Sarcopenia is an emerging marker of frailty. Its prognostic impact on atherosclerotic cardiovascular disease (ASCVD) requires further investigation.

Purpose

We investigated the long-term prognostic impact of computed tomography (CT)-determined sarcopenia in patients with coronary artery disease (CAD).

Methods

Total 475 CAD patients those who underwent successful percutaneous coronary intervention (PCI) and performed CT scan within 30 days of PCI were enrolled. The cross-sectional area of skeletal muscle at the first lumbar vertebra (L1) level was measured. Sarcopenia was defined as L1 skeletal muscle index of less than 34.60 cm2/m2 for men and of less than 25.90 cm2/m2 for women. Primary outcome was 3-year all-cause mortality and secondary outcome was 3-year major adverse cardiovascular event (MACE), a composite of all-cause mortality, any myocardial infarction, and repeat revascularization.

Results

Sarcopenia was present in 214 (45.1%) of 475 patients. The incidence of 3-year all-cause mortality and MACE was significantly higher in patients with sarcopenia than in those without sarcopenia (17.7% vs. 5.7%, p<0.001; and 35.0% vs. 11.2%, p<0.001, respectively). In the fully adjusted multivariable analysis, sarcopenia was an independent predictor of higher risk of 3-year all-cause mortality (odds ratio [OR]: 2.98; 95% confidence interval [CI]: 1.35 to 6.58, p=0.007) and MACE (OR: 4.39; 95% CI: 2.49 to 7.73, p<0.001). The results were consistent after propensity-score matched analysis with 100 pairs of study population (C-statistics = 0.868).

Kaplan–Meier analysis of 3-year outcomes Overall population PSM population Sarcopenia (n=214) No sarcopenia (n=261) Log-rank p-value Sarcopenia (n=100) No sarcopenia (n=100) Log-rank p-value All-cause mortality 36 (17.7) 14 (5.7) <0.001 19 (20.0) 7 (7.7) 0.013 Non-fatal MI 12 (6.6) 5 (2.0) 0.021 6 (7.0) 2 (2.3) 0.134 Repeat revascularization 32 (20.3) 14 (6.2) <0.001 17 (23.3) 8 (8.0) 0.027 Total MACEs 68 (35.0) 27 (11.2) <0.001 36 (39.3) 14 (15.4) 0.001 Data are expressed as n (%). MACE = major adverse cardiovascular event; MI = myocardial infarction; PSM = propensity-score matched.

Clinical impact of sarcopenia on CAD

Conclusion

Sarcopenia is a useful predictor of adverse clinical outcomes in patients with CAD undergoing PCI. CT-determined sarcopenia may further aid in risk stratification and decision-making for patients with established ASCVD.

Acknowledgement/Funding

National Research Foundation of Korea (NRF-2016R1A2B3013825), Ministry of Future Creation and Science of Korea (2018K000255)

P4339Reference values for cardiorespiratory fitness in healthy Koreans: compared to western nations and nomogram

Introduction

Cardiorespiratory Fitness (CRF), defined as the integrated ability to properly oxygenate skeletal muscles during physical activity, is associated with a high risk of cardiovascular disease and all-cause mortality. The reference range for CRF may differ among nations, with Asians under-represented in previous data.

Purpose

In this study, we sought to establish reference values of CRF for Asians using a recent Korean cohort.

Methods

We analyzed 2646 healthy Korean adults recently enrolled in the Korea Institute of Sports Science Fitness Standards (KISS FitS) project with estimated maximal oxygen uptake (VO2max) values during treadmill test. Patients with cardiovascular or renal disease, systemic infection, pregnant women and those with orthopedic injuries unable to measure physical fitness were excluded. Age-specific mean VO2max values were compared with those from recent American, Norwegian, Danish cohorts and old Korean data.

Results

Age-specific reference values for healthy Korean adults in this cohort were as shown (Table). We were able to draw a nomogram to predict exercise capacity for a given age and MET value (Figure). When compared to other countries, less CRF reduction by aging was seen in Asians than in other Westerners. When compared to old Korean data from the 1980s, values were similar after adjustment for difference in methods, except for those under 30 years old which were decreased.

Exercise capacity of healthy Korean Men Women Age VO2max (ml/kg/min) N P-value for trend Age VO2max (ml/kg/min) N P-value for trend 19–29 42.3±6.3± 209 <0.01 19–29 34.3±4.3± 110 <0.01 30–39 42.0±5.0± 170 39–39 32.2±4.5± 211 40–49 41.4±5.6± 238 40–49 30.8±4.6± 284 50–59 38.0±5.7± 274 50–59 28.3±4.6± 367 60–69 32.4±6.2± 134 60–69 26.0±5.7± 336 70–79 27.2±5.6± 83 70–79 23.9±4.4± 195 >80 24.1±4.0± 11 >80 21.0±3.7± 24 Total 38.6±7.4± 1119 Total 28.5±5.8 1527 Data are presented as mean ± standard deviation. VO2max, maximal oxygen uptake; N, number.

Nomogram of exercise capacity in Koreans

Conclusions

While there was no significant change in CRF over time in the same ethnic group, there was a clear inter-ethnic difference. CRF should be assessed according to ethnic or national standards, and it is necessary to establish a reference for each nation or ethnicity with periodic updates.

Acknowledgement/Funding

National Sports Promotion Fund of the Korea Sports Promotion Foundation in 2015

P2501Validation of FRIEND and ACSM equations for cardiorespiratory fitness: comparison to direct measurement in male CAD patients

Introduction

Cardiorespiratory fitness (CRF) is associated with a high risk of cardiovascular disease and all-cause mortality. The regression equation of American College of Sports Medicine (ACSM) was a preferred method for estimating maximal oxygen consumption (VO2max). It is well-known that CRF is overestimated in ACSM equation. Recently, Kokkinos reported more precise equation from the Fitness Registry and the Importance of Exercise National Database (FRIEND). Both equations were made from western healthy people.

Purpose

In this study, we compared VO2max estimated by ACSM and FRIEND equations to VO2max directly measured in male coronary artery disease (CAD) patients.

Methods

We analyzed 103 male CAD patients who underwent percutaneous coronary intervention and who participated in cardiac rehabilitation between June 2015 and December 2018. VO2max was directly measured by the gas exchange analysis during treadmill test with modified Bruce protocol. Exclusive criteria were pulmonary disease, chronic kidney disease on hemodialysis, malignancy, peripheral artery disease, insufficient cardiopulmonary exercise test and orthopedic injuries. Directly measured VO2max were compared to ACSM and FRIEND equations.

Results

Age-specific VO2max values, which were directly measured from male CAD patients, were shown in Table. Smaller CRF difference was shown in FRIEND equation than ACSM equation. Compared to the measured value, CRF estimated by ACSM equation was overestimated by 22%, but the one estimated by FRIEND equation had only 2% gap. Figure presents Bland-Altman plots. ACSM equation had the higher bias (5.52ml/kg/min) compared with FRIEND equation (0.200ml/kg/min).

Comparison table of VO2max estimated by ACSM and FRIEND equations with directly measured VO2max in male CAD patients Age Number VO2max (ml/kg/min) Measured ACSM % predicted FRIEND % predicted 30–39 4 29.5 ± (6.6) 35.7 ± (6.1) 122.3 ± (8.5) 29.1 ± (4.3) 100.1 ± (8.7) 40–49 20 29.1 ± (5.1) 35.7 ± (5.4) 123.6 ± (11.1) 29.1 ± (3.8) 101.2 ± (9.5) 50–59 32 25.6 ± (4.3) 31.5 ± (5.1) 123.8 ± (10.1) 26.2 ± (3.6) 103.2 ± (8.5) 60–69 27 26.0 ± (5.1) 31.1 ± (2.6) 120.5 ± (12.6) 25.9 ± (4.0) 100.8 ± (10.5) 70–79 18 21.2 ± (6.0) 26.8 ± (5.4) 123.2 ± (14.8) 22.8 ± (3.9) 105.2 ± (12.0) >80 2 25.0 ± (10.1) 22.8 ± (2.6) 97 ± (28.9) 19.9 ± (1.9) 85.1 ± (27.0) Total 103 25.7 ± (5.6) 31.4 ± (6.0) 122.2 ± (12.4) 26.1 ± (4.3) 102.1 ± (10.4) Data are presented as mean ± (standard deviation).

Bland-Altman plots

Conclusions

FRIEND equation can estimate CRF more accurately than ACSM equation, even in Asian patients with CAD.

4098Reduced skeletal muscle mass is associated to worsened long-term clinical outcomes in patients with coronary artery disease: a quantitative analysis by computed tomography

Background

Sarcopenia is closely associated to poor clinical outcomes in patients with atherosclerotic cardiovascular disease (ASCVD). However, it is unclear whether the skeletal muscle mass at baseline has quantitative effect on future cardiovascular outcomes.

Purpose

We investigated the quantitative effect of skeletal muscle mass on future cardiovascular outcomes in patients with coronary artery disease (CAD).

Methods

Total 475 patients those who underwent successful percutaneous coronary intervention (PCI) for CAD and performed computed tomography (CT) scan within 30 days of PCI were enrolled. The cross-sectional area of skeletal muscle at the first lumbar vertebra (L1) level was measured. Whole study population was divided into 4 groups according to the sex-specific quartiles of skeletal muscle index (SMI). Primary outcome was all-cause mortality and secondary outcome was major adverse cardiovascular event (MACE) within 3 years of follow-up.

Results

Mean follow-up duration was 4.11±3.02 years and average time period from the date of PCI to CT scan was −3.33±11.72 days. The incidence of 3-year all-cause mortality (23.2% vs. 9.9% vs. 6.6% vs. 4.4%, p<0.001) and MACE (42.9% vs. 24.0% vs. 14.3% vs. 6.2%, p<0.001) was significantly higher in the group of lower quartiles of L1-SMI. In the fully adjusted multivariable analysis, lower quartiles of L1-SMI was an independent predictor of higher risk of all-cause mortality and MACE (lowest vs. highest quartile; OR: 4.90, 95% CI: 1.54 to 15.5, p=0.007; and OR: 12.3, 95% CI: 4.99 to 30.4, p<0.001, respectively).

Results of 3-year clinical outcomes SMI Q1 (n=124) SMI Q2 (n=116) SMI Q3 (n=112) SMI Q4 (n=123) Log-rank p-value All-cause mortality 27 (23.2) 11 (9.9) 7 (6.6) 5 (4.4) <0.001 Non-fatal MI 9 (8.7) 3 (3.0) 2 (2.0) 3 (2.6) 0.038 Repeat revascularization 20 (24.9) 15 (15.2) 7 (7.1) 4 (3.8) <0.001 Total MACEs 47 (42.9) 26 (24.0) 15 (14.3) 7 (6.2) <0.001 Data are expressed as n (%). MACE = major adverse cardiovascular event; MI = myocardial infarction; SMI = skeletal muscle index; Q = quartile.

Impact of reduced skeletal muscle on CAD

Conclusion

Skeletal muscle mass at baseline is a powerful predictor of future adverse clinical outcomes in patients with CAD undergoing successful PCI. Quantitative assessment of skeletal muscle mass at L1 level by CT scan provides prognostic implication for future cardiovascular risk stratification.

Acknowledgement/Funding

National Research Foundation of Korea (NRF-2016R1A2B3013825), Ministry of Future Creation and Science of Korea (2018K000255)

P2523Hand grip strength as a predictor of exercise capacity in coronary heart disease

A recent study has shown that quadriceps strength can be used to predict the level of exercise capacity in patients with coronary heart disease (CHD). We investigated whether the relationship between muscular strength and exercise capacity is also observed with hand grip strength (HGS). We studied 443 participants (age, 61.8±11.2 y; 77.7% male) who underwent coronary intervention and participated in cardiac rehabilitation between 2015 and 2018. Participants were assessed for grip strength, measured using a Jamar dynamometer. Logistic regression was used to assess the relationship between various clinical measures (HGS, age, sex, etc) with the distance walked on a 6-minute walk test (6MWT) and maximal oxygen uptake (VO2max). HGS was significantly related to distance walked on the 6MWT (r=0.435, p<0.001). It was the only predictor of all exercise capacity categories, and one of the strongest predictors of each exercise capacity category. A HGS of 25.5% of body weight predicted an achievement of a 200 m walk on the 6MWT (positive predictive value = 0.95). However, HGS less than 35.5% of body weight predicted that 500m could not be done in 6 minutes (negative predictive value = 0.97). This trend was also observed in the subgroups in which VO2max was measured. This study demonstrates that HGS is associated with exercise capacity in CHD and can be used to predict the level of exercise capacity. These findings may contribute to setting the recommended level of daily activity as well as the level of cardiac rehabilitation in CHD.

Logistic regression models for different levels of exercise capacity Level of exercise capacity B±S.E p-value Odd ratio 95% CI Distance of 6MWT   200 m Grip strength 0.054±0.014 <0.001 1.056 1.027–1.086   300 m Grip strength 0.042±0.009 <0.001 1.042 1.024–1.062   400 m Grip strength 0.047±0.011 <0.001 1.048 1.026–1.070   500 m Grip strength 0.051±0.016 0.001 1.053 1.021–1.086 VO2max level   4 METs Grip strength 0.054±0.010 <0.001 1.056 1.036–1.076   6 METs Grip strength 0.059±0.011 <0.001 1.061 1.039–1.083   8 METs Grip strength 0.081±0.015 <0.001 1.085 1.053–1.117   10 METs Grip strength 0.113±0.049 0.019 1.12 1.019–3.232 Data are presented as mean ± standard deviation (SD). 6MWT, 6-minute walk test; STEMI, ST-Elevation Myocardial Infarction; SE, standard error; CI, confidence interval; VO2max, Maximal Oxygen uptake; METs, Metabolic equivalents.

P6445Stress hyperglycemia and in-hospital mortality in patients with ST-segment elevation myocardial infarction

Introduction

Stress hyperglycemia is common in acute ill patients and associated with poor clinical outcomes. Some studies demonstrated the association of stress hyperglycemia and poor outcomes in acute MI. However, current results for the impact of stress hyperglycemia on mortality in acute MI who underwent PCI are insufficient.

Purpose

We aimed to evaluate the impact of stress hyperglycemia on clinical outcomes of patients with STEMI underwent primary PCI in large scale multi-center registry.

Methods

From 2007 to 2014, in 1,538 patients of the INTERSTELLAR (Incheon-Bucheon Cohort of Patients Undergoing Primary PCI for Acute ST-Elevation Myocardial Infarction) cohort, 997 patients without diabetes who underwent primary PCI for STEMI were retrospectively analyzed. We defined random glucose more than 200mg/dl at admission without diabetic history or results of HbA1C more than 6.5% as stress hyperglycemia. The primary endpoint was in-hospital all-cause death and the secondary endpoint was all-cause death within 1 year after index PCI.

Results

From 997 nondiabetic cohort population, 117 patients with stress hyperglycemia and 880 patients without stress hyperglycemia were enrolled. Baseline characteristics including age, sex, hypertension, hyperlipidemia, atrial fibrillation, left main disease, and multivessel disease were not significantly different between two groups. However, systolic blood pressure was lower (111.2±39.2 vs. 125.5±28.1, p<0.001) and hypoxic liver injury was frequent (31.0% vs. 20.1%, p=0.007) in stress hyperglycemia. In-hospital and 1-year all-cause mortality were higher in stress hyperglycemia (13.7% vs. 2.7%, p<0.001; 15.4% vs. 3.8%, p<0.001, respectively). However, there is no significant difference in post-discharge mortality rate. Stress hyperglycemia was a significant independent predictor of in-hospital death (adjusted OR: 5.67, 95% CI: 2.40–13.39; p<0.001). Hypotension (defined less than 90mmHg) and left ventricular dysfunction (defined less than 40% of LVEF on echocardiography) were significantly associated with stress hyperglycemia (adjusted OR: 5.72, 95% CI: 3.33–9.82; p<0.001; adjusted OR: 2.38, 95% CI: 1.49–3.82; p<0.001, respectively).

Landmark analysis of all-cause death

Conclusions

In nondiabetic patients who underwent primary PCI for STEMI, stress hyperglycemia is significantly associated with an increased in-hospital all-cause mortality but did not increase post-discharge mortality within 1 year.

Implementation of biological variation-based analytical performance specifications in the laboratory: Stringent evaluation of Improvacutor blood collection tubes

Recently, because the quality of laboratory analyses has increased along with the need for quality improvement, several external quality control bodies have adapted performance specifications using the Desirable Biological Variation Database, termed “Ricos goals”; these criteria are more stringent than those presented in CLIA 88. In this study, we aimed to validate newly introduced serum separator tubes, Improvacutor, for routine clinical chemistry testing in accordance with Ricos goals and CLIA 88. Blood samples were collected from 100 volunteers into three types of serum vacuum tubes: Greiner Vacuette, Becton Dickinson (BD) Vacutainer, and Improve Improvacutor. The samples were subjected to 16 routine chemistry tests using a TBA-200fr NEO chemistry autoanalyzer. In the comparison analysis, all 16 test results were acceptable according to CLIA 88. However, in the comparison of Improve and BD tubes, creatinine showed 4.31% (+0.08 μmol/L) bias. This slightly exceeded the Desirable Specification for Inaccuracy Ricos limit of ±3.96%, but still satisfied the CLIS88 limit of ±26.52 μmol/L. The remaining 15 analytes performed acceptably according to the Desirable Specifications of Ricos. The correlation coefficient of 12 analytes was greater than 0.95 in Passing-Bablok regression analysis among the three tubes, but was lower for four analytes: calcium, sodium, potassium, and chloride. In the stability assay, only potassium tested in the Greiner tube revealed a larger positive bias (2.18%) than the Ricos Desirable Specification for Inaccuracy based on biologic variation (1.8%). The BD tube also showed a positive bias of 1.74%, whereas the new Improve tube showed the smallest positive bias of 1.17% in potassium level after 72 h storage. Thus, the results of this study demonstrate that recently introduced analytical performance specifications based on components of biological variation (Rico's goal) could be extended to criterion for performance evaluation and applied.

Novel effects of sarcopenic osteoarthritis on metabolic syndrome, insulin resistance, osteoporosis, and bone fracture: the national survey

This study compared the effects sarcopenic osteoarthritis on metabolic syndrome, insulin resistance, osteoporosis, and bone fracture. By using national survey data, we suggest that the relationship between sarcopenia and metabolic syndrome or insulin resistance is potentiated by the severity of osteoarthritis and is independent of body weight.

INTRODUCTION

Sarcopenia and osteoarthritis are known risk factors for metabolic syndrome. However, their combined effects on metabolic syndrome, insulin resistance and osteoporosis remain uncertain.

METHODS

We used data from the fifth Korean National Health and Nutrition Examination Survey using a total of 3158 adults (age >50 years). Sarcopenia was defined as a skeletal muscle index score (appendicular skeletal muscle mass/body weight) within the fifth percentile of sex-matched younger reference participants. Radiographic knee osteoarthritis was defined as a Kellgren-Lawrence (K-L) grade of 2 or greater. Metabolic syndrome was diagnosed using the National Cholesterol Education Program criteria. Insulin resistance was evaluated using the homeostasis model assessment-estimated insulin resistance index (HOMA-IR). Osteoporosis was defined using the World Health Organization T-score criteria.

RESULTS

In multivariable logistic regression analysis, the sarcopenic osteoarthritis group had a higher odds ratio (OR) for metabolic syndrome (OR = 11.00, 95 % confidential interval (CI) = 2.12-56.99, p = 0.013) than the non-sarcopenic osteoarthritis (OR = 1.02, 95 % CI = 0.65-1.62, p = 0.972) and sarcopenic non-osteoarthritis groups (OR = 7.15, 95 % CI = 1.57-32.53, p = 0.027). Similarly, sarcopenic osteoarthritis had a greater OR of highest HOMA-IR quartiles (OR = 8.19, 95 % CI = 2.03-33.05, p = 0.003) than the other groups. Overall, the association between the K-L grade and body mass index was significant; however, this significance was lower in individuals with sarcopenia and was lost in those with sarcopenic osteoarthritis. Additionally, osteoporosis and bone fracture were not associated to sarcopenic osteoarthritis (p > 0.05).

CONCLUSIONS

These results suggest that the relationship between sarcopenia and metabolic syndrome or insulin resistance is potentiated by the severity of osteoarthritis and is independent of body weight.

Effect of electrode positions on the mixing characteristics of an electroosmotic micromixer

In this study, an electrokinetic microchannel with a ring-type mixing chamber is introduced for fast mixing. The modeled micromixer that is used for the study of the electroosmotic effect takes two fluids from different inlets and combines them in a ring-type mixing chamber and, then, they are mixed by the electric fields at the electrodes. In order to compare the mixing performance in the modeled micromixer, we numerically investigated the flow characteristics with different positions of the electrodes in the mixing chamber using the commercial code, COMSOL. In addition, we discussed the concentration distributions of the dissolved substances in the flow fields and compared the mixing efficiency in the modeled micromixer with different electrode positions and operating conditions, such as the frequencies and electric potentials at the electrodes.

Association of hypertension with small, dense low-density lipoprotein in patients without metabolic syndrome

A higher proportion of small, dense low-density lipoprotein (sdLDL) is known to be associated with a high prevalence of cardiovascular disease in association with metabolic syndrome (MS). Hypertension (HTN) is one of the known risk factors for MS. However, whether HTN is associated with sdLDL in patients without MS is not yet clear. The lipid profiles, including low-density-lipoprotein (LDL) subfractions, of 383 consecutive subjects were evaluated. The patients without MS consisted of 198 hypertensive patients (non-MS/HTN group) and 108 normotensive subjects (non-MS/non-HTN group). The peak and mean particle diameter of LDL were measured by gradient gel electrophoresis. Plasma total cholesterol, LDL cholesterol, high-density lipoprotein (HDL) cholesterol, triglyceride (TG), HDL cholesterol/Apo A1, LDL-C/ApoB and Apo(A1, B, CII and E) levels did not differ between the non-MS/non-HTN and non-MS/HTN groups. When analyzing LDL subfraction, the absolute amount of patterns A and B was not different between the non-MS/non-HTN and non-MS/HTN groups. Compared with the non-MS/non-HTN groups, the proportion of sdLDL was higher in the non-MS/HTN group (37.7% versus 39.9%, P=0.046), but not significant after adjustment of waist circumference, serum TG, age and statin usage. The proportion of sdLDL to total LDL was higher in hypertensive subjects, even those without MS, than in normotensive subjects. However, this difference of LDL subfraction in hypertensive patients is associated with higher waist circumference, higher serum TG, older age and more statin usage. This result suggests that HTN may contribute to atherosclerosis and endothelial dysfunction with associated risk factors that influence LDL size.

Correlation between CT and diffusion-weighted imaging of acute cerebral ischemia in a rat model

BACKGROUND AND PURPOSE

The quantitative temporal relationship between changes in CT attenuation, ADC value, and DWI signal intensity of acute ischemic tissue has not yet been determined in an animal model. This study was performed to determine the temporal relationship between CT attenuation, ADC value, and DWI signal intensity in acute cerebral ischemia.

MATERIALS AND METHODS

CT and DWI were performed at 1, 3, 5, 7, and 9 hours after left MCA occlusion in 11 rats. Mean values for CT attenuation, ADC, and DWI signal intensity were determined for the ischemic hemisphere and contralateral normal hemisphere. Temporal changes in each mean value and the relationship between CT attenuation and ADC value and DWI signal intensity were evaluated.

RESULTS

The decrease of CT attenuation and the increase of DWI signal intensity occurred gradually after MCA occlusion, while ADC value decreased rapidly at 1 hour. Although correlation was significant between time and rCT or rDWI (P<.01, respectively), no correlation between time and rADC was found (P=.33). There was a significant linear correlation between rCT and rDWI (r=0.497, P<.01), but no significant correlation between rCT and rADC (P=.509) was found.

CONCLUSIONS

The temporal change in CT attenuation was different from that in ADC value with no significant linear correlation between CT attenuation and ADC value for acute cerebral ischemia. However, rCT and rDWI showed a modest correlation.

The diagnostic value of the sagittal multiplanar reconstruction CT images for nasal bone fractures

AIM

To compare the diagnostic performance of sagittal multiplanar reconstruction (MPR) images and axial images for the detection of a nasal bone fracture.

MATERIALS AND METHODS

This prospective study included 533 consecutive patients who underwent three-dimensional images with 64-section multidetector-row CT for the evaluation of a facial bone fracture between June 2007 and May 2008 (366 males; 167 females; mean age +/- standard deviation 31.1+/-21.2 years; age range 1-92 years). Two observers independently scored the possibility of a nasal bone fracture on axial and sagittal images. Receiver operating characteristic (ROC) curve analysis was performed.

RESULTS

The Az values of the sagittal images were higher than those of the axial images for both observers (p=0.002 and 0.010, respectively) with higher accuracy (p<0.001 and 0.016, respectively). The sensitivities of sagittal images were superior to those of axial images, especially for type 1simple nasal bone fractures with no or minimal displacement (observer 1, 98.6 versus 72.8%; observer 2, 84.9 versus 71%).

CONCLUSION

Sagittal MPR facial bone CT images provided superior diagnostic performance, and their addition to axial images is useful for the evaluation of nasal bone fractures.

Nonenhancing intramedullary astrocytomas and other MR imaging features: a retrospective study and systematic review

BACKGROUND AND PURPOSE

Most intramedullary astrocytomas have been known to exhibit at least some enhancement on MR imaging regardless of cell type or tumor grade. The purpose of this study was to evaluate the incidence of nonenhancing intramedullary astrocytomas through a retrospective study within our institutions and a systematic review of the medical literature.

MATERIALS AND METHODS

A total of 19 consecutive patients (male to female ratio, 11:8; mean age, 27.84 +/- 19.0 years) with primary intramedullary astrocytomas (3 WHO grade I, 13 WHO grade II, 3 WHO grade III) who underwent preoperative MR imaging with contrast enhancement were included in this retrospective study from 4 institutions. The tumor-enhancement patterns were classified into the following categories: 1) no enhancement, 2) focal nodular enhancement, 3) patchy enhancement, 4) inhomogeneous diffuse enhancement, and 5) homogeneous diffuse enhancement. Seven articles including MR imaging enhancement studies of intramedullary astrocytomas were eligible for literature review.

RESULTS

In the retrospective study, 6 astrocytomas (32%), including 2 anaplastic astrocytomas, did not enhance at all. Focal nodular enhancement was identified in 5 astrocytomas (26%); patchy enhancement, in 3 (16%); inhomogeneous diffuse enhancement, in 5 (26%); and homogeneous diffuse enhancement, in none. In the literature review, the frequency of nonenhancing intramedullary astrocytomas was 14 of 76 (18%), including 2 anaplastic astrocytomas.

CONCLUSIONS

Nonenhancing intramedullary astrocytomas are not uncommon and comprise between 20% and 30% of intramedullary astrocytomas. Therefore, astrocytoma must remain in the differential diagnosis of nonenhancing intramedullary lesions, particularly if the lesion demonstrates a prominent mass effect or cord expansion.

Impact of hypertension on coronary artery spasm as assessed with intracoronary acetylcholine provocation test

Both hypertension and coronary artery spasm (CAS) are associated with endothelial dysfunction. Thus, a higher incidence of CAS is expected in hypertensive patients. We evaluated the impact of hypertension on CAS with intracoronary acetylcholine (ACh) provocation test. A total of 986 patients (685 hypertensive patients vs 301 normotensive patients) who underwent coronary angiography with ACh provocation test were enrolled. ACh was injected into the left coronary artery in incremental doses of 20, 50 and 100 microg min(-1). Significant CAS was defined as a transient >70% luminal narrowing with concurrent chest pain and/or ST-segment changes. Although the incidences of significant ACh-induced CAS were similar between hypertensive and normotensive patients (35.8 vs 39.2%, P=0.303), multivariate logistic analysis showed that hypertension was negatively associated with ACh-induced CAS (odds ratio: 0.70, 95% confidence interval: 0.51-0.94, P=0.020). The angiographic characteristics of ACh-induced CAS were similar between these two groups. Subgroup analysis regarding the impact of the status of blood pressure control on CAS showed that hypertensive patients with controlled blood pressure had a significantly higher incidence of CAS than those with uncontrolled blood pressure (45.2 vs 27.9%, P<0.001), and that uncontrolled blood pressure was negatively associated with ACh-induced CAS (odds ratio: 0.56, 95% confidence interval: 0.40-0.79, P=0.001). In conclusion, despite the expected endothelial dysfunction, hypertension and uncontrolled blood pressure are negatively associated with CAS, suggesting that the mechanisms and risk factors of CAS may be significantly different from those of coronary artery disease.

Gain-clamped Raman fiber oscillator

Gain band expansion of a Raman amplifier based on a Raman fiber oscillator (RFO) was tested with two Raman lasers, which yielded a broad gain spectrum of about 40 nm. However, they also introduced gain-clamping behavior in the short-wavelength range and abnormal excessive gain in long-wavelength channels, which were undesirable for practical application. The proper mechanism of the behavior was analyzed and experimentally demonstrated to apply to a gain-clamped (GC) amplifier based on a RFO. Appropriate configuration of the GC-RFO for wide gain bandwidth was proposed and characterized.

Implication of lipocalin-2 and visfatin levels in patients with coronary heart disease

OBJECTIVES

Visfatin and lipocalin-2 are novel adipokines associated with insulin resistance (IR) and obesity-related metabolic disorders. We compared lipocalin-2 and visfatin concentrations between patients with coronary heart disease (CHD) and control subjects and evaluated their association with cardiovascular risk factors.

METHODS

We examined serum visfatin, lipocalin-2 levels, and cardiovascular risk factors in 91 subjects (49 patients with angiographically confirmed CHD versus 42 age- and gender-matched control participants).

RESULTS

Circulating lipocalin-2 levels were significantly higher in patients with CHD compared with the control subjects (82.6+/-38.7 ng/ml versus 43.8+/-27.8 ng/ml; P<0.001). However, visfatin levels were not significantly different between patients with CHD and control subjects. Serum lipocalin-2 levels were positively associated with weight (r=0.26; P=0.036), fasting insulin (r=0.36; P=0.003), and IR (r=0.33; P=0.007), whereas these levels showed a negative correlation with high-density lipoprotein (HDL) cholesterol (r=-0.30; P=0.016) after adjustment for gender and body mass index. However, visfatin levels were not associated with any variables of the metabolic syndrome. The multiple regression analysis showed that lipocalin-2 levels were independently associated with HDL cholesterol and IR (R2=0.199). Furthermore, the multiple logistic regression analysis showed that systolic blood pressure, IR, and lipocalin-2 levels were independently associated with CHD.

CONCLUSIONS

Serum lipocalin-2 levels were significantly elevated in patients with CHD and were independently associated with CHD. The present findings suggest that the measurement of serum lipocalin-2 levels may be useful for assessing CHD risk.

High b-value diffusion (b = 3000 s/mm2) MR imaging in cerebral gliomas at 3T: visual and quantitative comparisons with b = 1000 s/mm2

BACKGROUND AND PURPOSE

High b-value diffusion-weighted imaging (DWI) provides different features not appreciated at lower b-value and have been recently studied in several clinical issues. The purpose of this study was to assess whether DWI at b = 3000 s/mm(2) is more useful in discriminating high-grade and low-grade gliomas than DWI at b = 1000 s/mm(2) at 3T.

MATERIALS AND METHODS

DWIs at both b = 1000 and 3000 s/mm(2) were performed at 3T in 62 patients, 49 high-grade gliomas (20 World Health Organization [WHO] grade III and 29 grade IV) and 13 low-grade gliomas (13 grade II). Visual assessments based on 5-point scaled evaluations, receiver operating characteristic (ROC) curve analysis, and quantitative assessment based on DWI signal intensity (SI) ratio (tumor SI/normal SI) and apparent diffusion coefficient (ADC) values were compared between DWIs at b = 1000 and 3000 s/mm(2).

RESULTS

By visual assessment, DWI at b = 3000 s/mm(2) showed more conspicuous hyperintensity in high-grade gliomas and hypointensity in low-grade gliomas than DWI at b = 1000 s/mm(2). Sensitivity and specificity at b = 3000 s/mm(2) were higher than at b = 1000 s/mm(2) (83.7%, 84.6% vs 69.4%, 76.9%, respectively). Quantitative assessments showed that mean SI ratio of high-grade gliomas was significantly higher than that of low-grade gliomas at both b-values. The mean ADC value of high-grade gliomas was significantly lower than that of low-grade gliomas at both b-values. The difference between the SI ratios of high-grade and low-grade gliomas was significantly larger at b = 3000 s/mm(2) than at b = 1000 s/mm(2).

CONCLUSION

DWI at b = 3000 s/mm(2) is more useful than DWI at b = 1000 s/mm(2) in terms of discriminating high-grade and low-grade gliomas at 3T.

Myocardial bridging is related to endothelial dysfunction but not to plaque as assessed by intracoronary ultrasound

BACKGROUND

Myocardial bridge (MB) is characterised by focal compression of a coronary artery in systole by an overlying band of myocardium. Chronic compression and relaxation of the MB may produce endothelial dysfunction by direct stress.

OBJECTIVE

To determine whether MB alters endothelial function, thus influencing the plaque formation.

METHODS

128 patients (mean (SD) age 54.7 (10.9) years, 56 men) with typical angiographic systolic milking effects and >30% reduction in diameter of the coronary artery during systole after intracoronary nitrate (glyceryl trinitrate, 200 mug) infusion were studied. 231 control patients (mean (SD) age 52.9 (12.1) years, 111 men) without overt coronary artery disease including MB were also studied. Endothelial function was estimated by incremental acetylcholine (Ach) infusion into the left coronary ostium. Intracoronary ultrasound assessments were obtained in 74/128 patients with MB and 81/231 controls.

RESULTS

The mean (SD) vasoconstrictive response to maximal Ach was more pronounced at the bridging segments than at matched segments in controls (-71.9 (14.9) vs -30.3 (22.6), p = 0.009). Coronary vasoconstriction (>50%) to Ach was seen more often in the MB group than in controls (114/128 (89.1%) vs 81/231 (35.1%), p = 0.007). No significant correlation was found between the severity of MB and vasoconstriction in response to Ach. A typical half-moon phenomenon was seen in 71/74 (95.9%) cases of the MB group, but not in controls (p<0.001). Plaques at the bridging segments were absent in 67/74 (90.5%) and mild in 7/74 (9.5%) cases, as compared with those of matched segments of the left anterior descending coronary artery in controls (plaque burden 5.91 (1.37)% vs 24.71 (24.21)%, p = 0.002).

CONCLUSION

Despite the prominent relationship between MB and endothelial dysfunction, bridging segments are spared from atherosclerotic plaque formation.

Relationship between blood pressure parameters and pulse wave velocity in normotensive and hypertensive subjects: invasive study

Blood pressure (BP) is one of the most important contributing factors to pulse wave velocity (PWV), a classic measure of arterial stiffness. Although there have been many non-invasive studies to show the relation between arterial stiffness and BP, the results are controversial. The aim of this study is to evaluate the role of BP as an influencing factor on PWV using invasive method. We observed 174 normotensive and untreated hypertensive subjects using coronary angiography. Arterial stiffness was assessed through aorto-femoral PWV by foot-to-foot velocity method using fluid-filled system. And BP was measured by pressure wave at the right common femoral artery. From univariate analysis, age, diabetes mellitus (DM), hypertension, waist, waist-to-hip ratio, total cholesterol-to-high-density lipoprotein cholesterol ratio, systolic BP (SBP), pulse pressure (PP) and mean arterial pressure (MAP) showed significant association with PWV. To avoid multiple colinearity among SBP, PP and MAP, we performed multiple regression analysis predicting PWV thrice. Age, DM and each BP were significantly and consistently correlated to PWV. In the first and third modules, compared to age, SBP and MAP were less strong predictors, respectively. However, PP was the stronger predictor than age and DM in the second module. Lastly, we simultaneously forced MAP and PP with other variables in the fourth multivariate analysis. Age, DM and PP remained significantly correlated with PWV, but the significance of MAP was lost. This is the first invasive study to suggest that PP has the strongest correlation with PWV among a variety of BP parameters.

Radiofrequency thermal ablation of hepatic tumors: pitfalls and challenges

Image-guided radiofrequency (RF) thermal ablation has been accepted as a promising interventional technique to control unresectable hepatic tumors. One important key to maximize the efficacy of RF ablation is to adhere to the therapeutic guidelines and to avoid preventable pitfalls. There are also several challenges obstructing successful ablation: poor approach path; small sonic window during multiple overlapping ablations; incomplete ablation due to the heat sink effect; subcapsular mass (too exophytic or the mass is adjacent to the gastrointestinal tract); focal residual tumors; too isoechoic or small masses; and mistargeting to adjacent another lesion. Knowledge of these challenges and pitfalls in RF ablation is helpful for a successful ablation.

Delayed severe multivessel spasm and aborted sudden death after Taxus stent implantation

Sudden cardiac arrest associated with major spasm of three coronary arteries was observed about 10 hours after Taxus stent insertion in a three vessel lesion and was successfully treated by intracoronary glyceryl trinitrate infusion. This case illustrates a potential risk associated with drug eluting stent and alerts clinicians to the life threatening risk of spasm when stenting multiple vessels with drug eluting stent (especially the Taxus stent).

Inflammation, insulin resistance, and glucose intolerance in acute myocardial infarction patients without a previous diagnosis of diabetes mellitus

We examined the prevalence of impaired glucose metabolism and its association with inflammation and insulin resistance (IR) in acute myocardial infarction (AMI) patients without a previous diagnosis of diabetes. This prospective study enrolled 52 AMI patients, and 75-g oral glucose tolerance testing was performed on 30 patients at discharge and again 3 months later. We also measured serum adiponectin, high sensitive C-reactive protein, and IL-6 on both occasions. Data were compared with those of 30 type 2 diabetic patients without a history of AMI. Forty percent and 36.7% of AMI patients had impaired glucose tolerance (IGT) at discharge and at 3 months, respectively. The corresponding proportions for newly diagnosed diabetes are 33.0% and 30.0%. At discharge, AMI patients with IGT or diabetes showed higher high sensitive C-reactive protein and IL-6 levels compared with AMI patients with normal glucose tolerance or control type 2 diabetic patients. Furthermore, AMI patients with IGT or diabetes exhibited higher IR and lower serum adiponectin levels than AMI patients with normal glucose tolerance at 3 months after discharge. Previously undiagnosed diabetes and IGT are common in Korean patients with AMI. These glycometabolic abnormalities are associated with inflammation, IR, and serum adiponectin levels.

Anti-protozoal efficacy of high performance liquid chromatography fractions of Torilis japonica and Sophora flavescens extracts on Neospora caninum and Toxoplasma gondii

We previously reported that alcoholic extracts of Sophora flavescens and Torilis japonica from South Korea demonstrated good efficacy in reducing replication of Toxoplasma gondii and Neospora caninum. To characterize the chemical component associated with anti-protozoal activity, specific fractions were isolated by high performance liquid chromatography (HPLC) and used for in vitro testing. These fractions were evaluated in vitro against T. gondii and N. caninum. Fractions of the herb extracts were serially diluted to final concentrations of 2.850 to 0.356 ng/ml in medium and added to wells containing replicating T. gondii and N. caninum. To determine the ability of each fraction to inhibit parasite proliferation, 3H-uracil incorporation was used to determine parasite replication. In cultures infected with T. gondii, a fraction of T. japonica (TJ2) inhibited T. gondii proliferation by 99.2, 94.4, 88.6 and 27.0% in the range from 2.850 to 0.356 ng/ml. Four fractions of S. flavescens (SF1-SF4) inhibited T. gondii proliferation by 99.6-60.6, 96.9-48.1, 92.3-68.2 and 95.4-52.9% in the range from 2.850 to 0.356 ng/ml. In cultures infected with N. caninum, a fraction of T. japonica (TJ2) inhibited N. caninum proliferation by 98.3, 95.5, 79.7 and 30.6% in the range from 2.850 to 0.356 ng/ml. Four fractions of S. flavescens (SF1-SF4) inhibited N. caninum proliferation by 97.1-25.9, 94.8-35.5, 95.9-33.7 and 95.4-49.4% in the range from 2.850 to 0.356 ng/ml. These fractions of T. japonica and S. flavescens extracts are currently undergoing in vivo evaluation in experimentally infected mice.

Cecal rupture by Anoplocephala perfoliata infection in a thoroughbred horse in Seoul Race Park, South Korea

A 7-year-old Thoroughbred horse was admitted to the Equine Hospital, Korea Racing Association with signs of colic. Based on the size of impactions, the clinical signs, the results of abdominal paracentesis and medical treatment, the prognosis was poor. The horse died 3 hours later following hopeless discharge. At necropsy, the caecum and large colon were fully filled with fecal contents and there was a rupture (10 cm in dia) in the latero- ventral caecum. The mucosa of the ileo-caecal and caeco- colic valves appeared to the hyperemic, edematous and ulcerous. There were many tapeworms in the affected mucosa. Histopathologically, lesions included hyperaemia, a deep necrotic inflammatory lesion and ulcers in the mucosa and submucosa of ileo-caecal and caeco-colic valves. One hundred thirty four faecal samples were obtained from 16 stables and submitted to parasitic examination. A total of 4 genera of eggs were recovered: Stongylus spp (82.1%), Anoplocephala perfoliata (10.5%), Bovicola equi (0.7%) and Parascaris equorum (1.5%). The major findings in this study are the presence of A perfoliata and its suspected association with the colic which led into an eventual caecal rupture. This study indicates the needs for an epidemiological survey of colic that is associated with Anoplocephala.

The antithrombotic efficacy of AT-1459, a novel, direct thrombin inhibitor, in rat models of venous and arterial thrombosis

The antithrombotic efficacy of AT-1459, a novel, direct thrombin inhibitor (Ki = 4.9 nM) was evaluated in rat models of venous thrombosis combined with a bleeding time test and arterial thrombosis. After drugs were given by i. v. bolus injection plus a continuous infusion, the ID50, (a dose that exhibits 50% inhibition of thrombus formation over each vehicle group) values of AT-1459, argatroban, and dalteparin were 0.04 mg/kg plus 0.04 mg/kg/h, 0.1 mg/kg plus 0.4 mg/ kg/h, and 13.0 IU/kg plus 26.0 IU/kg/h, respectively, in the venous thrombosis study. The BT2 (a dose that causes 2-fold prolongation of bleeding time over each vehicle group) values of AT-1459, argatroban, and dalteparin were 0.9 mg/kg plus 0.9 mg/kg/h, 1.0 mg/kg plus 0.6 mg/kg/h, and 345.5 IU/kg plus 691.0 IU/kg/h in the rat tail transection model. The ratios of BT2/ID50 of AT-1459, argatroban, and dalteparin were 22.5, 10.0, and 26.6, respectively. In a rat model of arterial thrombosis induced by topical FeCl2 application, intravenous administration of AT-1459, argatroban, and dalteparin improved the vessel patency significantly (P < 0.01) at 0.6 mg/kg plus 0.6 mg/kg/h, 0.6 mg/kg plus 2.4 mg/kg/h, and 300 IU/kg plus 600 IU/kg/h, respectively. The oral antithrombotic effect of AT-1459 lasted for 6 after administering 30 mg/kg and improved the vessel patency significantly 1 h after administering the same dose in venous and arterial thrombosis models, respectively, with a rapid onset of action. Warfarin also inhibited thrombus weight and improved the vessel patency significantly after oral administration of 0.3 mg/kg for three consecutive days in the same study. The antithrombotic and hemorrhagic effects of all drugs studied were correlated with plasma concentration or clotting times. These results suggest that AT-1459 may be clinically useful as an orally available antithrombotic agent for the prevention of venous and arterial thrombosis.

Identification of Acanthocephala discovered in changran-pickles and myungran-pickles

To identify acanthocephala found in 'Changran-pickles' and 'Myungran-pickles' each organ was measured in permanent slides. In the present report, the results obtained were as follows: 1. Morphology of male worms: Worms possessed 18-19 longitudinal rows, with 4 hooks per row, which became smaller towards the base of proboscis. Each worm contained two testis and six cement glands arranged linearly. Body 22.0 by 0.8-0.6 mm and 15.0 by 0.6-0.4 mm, proboscis 284.8 by 227.6 micro m and 524.9 by 151.4 micro m, proboscis sheath 1570.7 by 72.7 micro m and 751.9 by 280.4 micro m, lemnisci length 2566.7 and 1085.6, testis 2202.9-1860.5 by 737.0-575.7 micro m and 1033.8-981.1 by 463.1-351.6 micro m, cement glands 940.2 by 441.2 micro m and 610.0 by 369.1 micro m. 2. Morphology of female worms: Worms possessed 14-18 longitudinal rows, with 6-10 hooks per row and become smaller toward the base of proboscis. Each worm contained an uterine bell and uterus in the posterior portion and the eggs filled the body cavity. Body, approximately 14.0 - 51.0 mm by 0.7-0.5 - 2.2-1.4 mm, proboscis 466.1-268.9 micro m by 259.9-252.0 micro m, proboscis sheath 1550.7-506.0 by 298.8-231.1 micro m, lemnisci length 1325.7-473.1 micro m, eggs approximately 112.4 by 28.5 micro m - 51.7 by 14.0 micro m. In this present study, the acanthocephala collected in 'Changran-pickles' and 'Myungran-pickles' were identified as Echinorhynchus gadi by morphological features.

The prevalence and awareness of hypertension and the relationship between hypertension and snoring in the Korean population

BACKGROUND

Hypertension is the most important, and yet modifiable, risk factor for cardiovascular diseases. But in many countries, hypertension remains poorly controlled. Moreover, sleep apnea syndrome has shown that it is correlated with hypertension. The purpose of this study was to investigate the prevalence, awareness and control of hypertension among the Korean people and to evaluate the relationship between hypertension and snoring.

METHODS

A total of 640 subjects living in Ansan, a regional city in Korea, were selected randomly, and trained nursing students investigated their age, sex, medical history, blood pressure, body mass index (BMI) and snoring score. Blood pressures were measured three times with a 10-minute interval and then averaged. The degree of snoring was estimated using a questionnaire. We divided the subjects into hypertensive (BP > or = 140/90 mmHg) versus normotensive group and snorer versus non-snorer group, and correlated hypertension with snoring.

RESULTS

Of 640 subjects, 311 were male. The mean age was 39.7 +/- 14.6 years (18-77 years), the mean BMI (body mass index) was 22.4 +/- 3.0 kg/m2. The mean systolic and diastolic blood pressure was 121 +/- 15.7 mmHg and 79.5 +/- 11.6 mmHg. The prevalence and awareness of hypertension were 22.2% and 16.9%, respectively, and the prevalence of snoring was 35.2%. With the increment of age, in the male, the prevalence of hypertension and snoring were higher, and the snorer group showed a higher risk of hypertension than the non-snorer group (Odds ratio 2.32, CI = 1.56-3.39, p = 0.0001).

CONCLUSION

In Korea, the prevalence of hypertension was similar to that in the western countries, but the awareness of hypertension was much lower compared with western countries. The prevalence of hypertension was higher in the snorer group, so more research on the correlation between the two conditions should be advanced in the future.