Anti-thrombotic effects of ginsenoside Rk3 by regulating cAMP and PI3K/MAPK pathway on human platelets

Background and objective

The ability to inhibit aggregation has been demonstrated with synthetically derived ginsenoside compounds G-Rp (1, 3, and 4) and ginsenosides naturally found in Panax ginseng 20(S)-Rg3, Rg6, F4, and Ro. Among these compounds, Rk3 (G-Rk3) from Panax ginseng needs to be further explored in order to reveal the mechanisms of action during inhibition.

Methodology

Our study focused to investigate the action of G-Rk3 on agonist-stimulated human platelet aggregation, inhibition of platelet signaling molecules such as fibrinogen binding with integrin αIIbβ3 using flow cytometry, intracellular calcium mobilization, dense granule secretion, and thromboxane B2 secretion. In addition, we checked the regulation of phosphorylation on PI3K/MAPK pathway, and thrombin-induced clot retraction was also observed in platelets rich plasma.

Key Results

G-Rk3 significantly increased amounts of cyclic adenosine monophosphate (cAMP) and led to significant phosphorylation of cAMP-dependent kinase substrates vasodilator-stimulated phosphoprotein (VASP) and inositol 1,4,5-trisphosphate receptor (IP3R). In the presence of G-Rk3, dense tubular system Ca2+ was inhibited, and platelet activity was lowered by inactivating the integrin αIIb/β3 and reducing the binding of fibrinogen. Furthermore, the effect of G-Rk3 extended to the inhibition of MAPK and PI3K/Akt phosphorylation resulting in the reduced secretion of intracellular granules and reduced production of TXA2. Lastly, G-Rk3 inhibited platelet aggregation and thrombus formation via fibrin clot.

Conclusions and implications

These results suggest that when dealing with cardiovascular diseases brought upon by faulty aggregation among platelets or through the formation of a thrombus, the G-Rk3 compound can play a role as an effective prophylactic or therapeutic agent.

The Inhibitory Effects of Protaetia brevitarsis seulensis Larvae Extract on Human Platelet Aggregation and Glycoprotein IIb/IIIa Expression

The white-spotted flower chafer, Protaetia brevitarsis seulensis, is used as a traditional remedy against liver cirrhosis, hepatitis, and hepatic cancer. In this study, we investigated if P. brevitarsis extract (PBE) inhibited platelet aggregation via integrin αIIb/β3 regulation. We observed that PBE inhibited αIIb/β3 activation by regulating the cyclic nucleotides, cyclic adenosine monophosphate and cyclic guanosine monophosphate. Additionally, PBE affected phosphatidylinositol-3 kinase, Akt, SYK, glycogen synthase kinase-3α/β, cytosolic phospholipase A2, and p38 expression, which are signal transduction molecules expressed by platelets, and consequently suppressed αIIbβ3 activity and thromboxane A2 generation. Taken together, PBE showed strong antiplatelet effects and may be used to block thrombosis- and platelet-mediated cardiovascular diseases.

Pharmacological Actions of 5-Hydroxyindolin-2 on Modulation of Platelet Functions and Thrombus Formation via Thromboxane A2 Inhibition and cAMP Production

Platelets play a very significant role in hemostasis while simultaneously posing a risk for the development of various cardiovascular diseases. Platelet-mediated issues can occur in blood vessels and trigger various medical problems. Therefore, controlling platelet function is important in the prevention of thrombosis. In this regard, we need to find compounds that provide potent antiplatelet activity with minimum side effects. Therefore, we examined the effect of 5-hydroxyindolin-2-one isolated from Protaetia brevitarsis larvae having antiplatelet properties and investigated different pathways that mediate the antiplatelet activity. We examined the effect of 5-hydroxyindolin-2-one (5-HI) on the regulation of phosphoproteins, thromboxane A₂ generation, and integrin αIIbβ3 action. Our data showed that human platelet aggregation was inhibited by 5-HI (75, 100, 150, 200 μM) without cytotoxicity, and it suppressed intracellular Ca²⁺ concentration through the regulation of inositol 1, 4, 5-triphosphate receptor I (Ser¹⁷⁵⁶) and extracellular signal-regulated kinase (ERK). Moreover, collagen-elevated thromboxane A₂ production and αIIbβ3 action were inhibited by 5-HI through the regulation of cytosolic phospholipase A₂ (cPLA₂), mitogen-activated protein kinase p38 (p38^MAPK), vasodilator-stimulated phosphoprotein (VASP), phosphoinositide 3-kinase (PI3K), and Akt (protein kinase B). Therefore, we suggested that 5-HI could be a potential substance for the prevention of thrombosis-mediated thrombosis.

Impact of estimated pulse wave velocity on cardiovascular outcomes in a general population

Background

Estimated pulse wave velocity (ePWV), a simple surrogate estimate of carotid-femoral pulse wave velocity which was gold standard for measuring aortic stiffness, has been demonstrated to predict cardiovascular (CV) outcome. However, there was limited data on its predictive capacity for CV outcomes in the general population. The study aim was to investigate the independent association between ePWV and CV outcomes in general population.

Methods

A total of 10,030 subjects aged between 40 and 69 years were followed over 18-year period in the Ansan-Ansung cohort study. Levels of ePWV, which was calculated from an equation based on age and mean blood pressure, were categorized according to quartiles. A major adverse cardiovascular event (MACE) was defined as a composite of myocardial infarction, coronary artery disease, stroke, heart failure, peripheral artery disease, and cardiovascular death.

Results

The incidence rates of CV death, and MACE were 7.0% and 22.1% in the fourth (highest) quartile of ePWV and 0.1% and 4.5% in the first (lowest) quartile of ePWV. After adjusting for relevant covariates, patients with third and fourth quartile of ePWV showed significantly higher risk of CV death (hazard ratio [HR] 3.92; 95% confidence intervals [CI] 1.09–14.15 in third quartile and HR 8.53; 95% CI 2.13–34.10 in fourth quartile), and MACE (HR 1.54; 95% CI 1.15–2.08 in third quartile and HR 1.56; 95% CI 1.05–2.32) compared to the reference of first (lowest) quartile of ePWV. However, there were no improvement of C statistic for CV death and MACE when adding ePWV to the Cox regression models with 10-year atherosclerotic cardiovascular disease (ASCVD) risk.

Conclusion

These results suggest that ePWV predicted CV death and MACE in general population. The value of ePWV, a simple and useful indicator of aortic stiffness, is expected to serve as a potential marker to identify high risk groups of CV event in general population.

Funding Acknowledgement

Type of funding sources: None.

Influence of concomitant percutaneous transluminal angioplasty with percutaneous coronary intervention on outcomes in patients with stable lower extremity artery disease

Background

Patients with stable lower extremity artery diseases (LEAD) frequently present with coronary artery diseases; thus, concomitant percutaneous transluminal angioplasty (PTA) at the time of percutaneous coronary intervention (PCI) is often performed. We investigated the influence of concomitant PTA on both cardiovascular (CV) and limb outcomes in the Korean National Health Insurance Service registry.

Methods

Among 78,185 patients undergoing PCI between 2012 and 2015, 6,563 patients (279 for the PTA+PCI group vs. 6,284 for the PCI group) suffering from stable LEAD without limb ischemia were included. Major adverse CV events (MACEs) were defined as a composite of CV death, myocardial infarction (MI) and coronary revascularization. Patients were followed for at least 3 years.

Results

After 1:5 propensity score matching was conducted, 279 patients in the PTA+PCI group and 1,385 patients in the PCI group were compared. The risk of all-cause death was higher in the PTA+PCI group than in the PCI group, whereas the risks of MACE, MI, revascularization, stroke, CV death and bleeding event were not different between the 2 groups in the matched cohort. In contrast, the risks of end-stage renal diseases and unfavorable limb outcomes were higher in the PTA+PCI group than in the PCI group (Figure 1). Mediation analyses revealed that amputation and repeat Percutaneous transluminal angioplasty after discharge significantly mediated the association between the concomitant PTA and all-cause death (Figure 2).

Conclusions

CPTA at the time of PCI is not associated with an increased risk of CV events but may increase the risk of all-cause death by increasing unfavorable renal and limb outcomes in patients with stable LEAD.

Funding Acknowledgement

Type of funding sources: None.

Anti-Thrombotic Effects of Artesunate through Regulation of cAMP and PI3K/MAPK Pathway on Human Platelets

Normal activation of platelets and their aggregation are crucial for proper hemostasis. It appears that excessive or abnormal aggregation of platelets may bring about cardiovascular diseases such as stroke, atherosclerosis, and thrombosis. For this reason, finding a substance that can regulate platelet aggregation or suppress aggregation will aid in the prevention and treatment of cardiovascular diseases. Artesunate is a compound extracted from the plant roots of Artemisia or Scopolia, and its effects have shown to be promising in areas of anticancer and Alzheimer’s disease. However, the role and mechanisms by which artesunate affects the aggregation of platelets and the formation of a thrombus are currently not understood. This study examines the ways artesunate affects the aggregation of platelets and the formation of a thrombus on platelets induced by U46619. As a result, cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) production were increased significantly by artesunate relative to the doses, as well as phosphorylated vasodilator-stimulated phosphoprotein (VASP) and inositol 1,4,5-trisphosphate receptor (IP₃R), substrates to cAMP-dependent kinase and cGMP-dependent kinase, in a significant manner. The Ca²⁺, normally mobilized from the dense tubular system, was inhibited due to IP₃R phosphorylation from artesunate, and phosphorylated VASP aided in inhibiting platelet activity via αIIb/β₃ platelet membrane inactivation and inhibiting fibrinogen binding. In addition, MAPK and PI3K/Akt phosphorylation was inhibited via artesunate in a significant manner, causing the production of TXA₂ and intracellular granular secretion (serotonin and ATP release) to be reduced. Therefore, we suggest that artesunate has value as a substance that inhibits platelet aggregation and thrombus formation through an antiplatelet mechanism.

Associations between changing patterns of ST-T waves morphologies in rest electrocardiography and cardiovascular risk in an asymptomatic low risk population: a report from Ansan-Ansung cohort study

Background

While clinical significance of ST-T wave abnormalities (STA) in rest electrocardiography (ECG) on long-term cardiovascular outcomes has been on debate, few studies have been reported on the association between the changes in ST-T waves in rest ECG and cardiovascular outcomes in low risk populations. We investigate the changing patterns of STA in rest ECG and the predictive value of the changes in ST-T wave in rest ECG for cardiovascular events in an asymptomatic general population.

Methods

A longitudinal community-based cohort study was conducted for 12 years. Koreans aged 40–69 years were followed biennially through scheduled revisit for comprehensive assessments. Among 10,030 participants, 6,648 participants who did not have any cardiovascular diseases, angina-related symptoms or pathologic Q waves in rest ECG at baseline were included for analysis. Changes in STAs were defined using the changes between ECG at baseline and that at the first revisit. A major adverse cardiovascular events was defined as a composite of cardiac death, myocardial infarction, clinical diagnosis of coronary artery disease and stroke.

Results

Among 5,924 participants without STA at baseline, only 187 participants (3.2%) developed new STA. Among 724 patients (10.9%) with STA at baseline, 274 patients (37.8%) persistently showed STA at the first revisit. MACEs occurred more frequently in the participants persistently with STA and those with newly-developed STA than in the participants persistently without STA (Figure 1). Multivariate Cox-proportional hazard models showed that a higher risk of MACE was only associated with the persisted STA (HR 1.69; 95% CI 1.10–2.63). In participants with baseline STA, persisted T-wave flattening was associated with a higher risk of MACE, whereas T-wave inversion, either persisted or fluctuated was not associated with a higher risk of MACE, compared with persistent absence of STA (Figure 2). In the participants without baseline STAs, multivariate Cox-proportional hazard model showed that newly-developed T-wave flattening (HR 1.85; 95% CI 0.20–2.84), not T-wave inversion (HR 1.50; 95% CI 0.85–2.65) was associated with a higher risk of MACE. Survival receiver operating curve analysis showed that the changes in STAs had a C-index of 0.538 (95% CI 0.511–0.558), a sensitivity of 13.0% and a specificity of 92.5% and add only a small value to the predictive power of 10-year atherosclerotic cardiovascular diseases risk estimator (C-index without STA changes 0.708 [0.681–0.736] vs. C-index with STA changes 0.721 [0.694–0.748]).

Conclusions

STAs uncommonly developed while frequently disappeared spontaneously in the asymptomatic general population. Persisted STA and newly developed STA in rest ECG were predictive of future cardiovascular events in the asymptomatic general population. However, the changes in STAs did not significantly improve the predictive value of the conventional risk estimator, when added.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Research Foundation of Korea Figure 1Figure 2

Simulation and validation for count-based binary decision of target blood pressure achievement in home blood pressure monitoring data analysis for clinical practice

Introduction

Home blood pressure monitoring (HBPM) is a useful tool to identify hypertension and to decide whether a patient's blood pressure (BP) is controlled. The use of automatized oscillometric BP measurement devices has become increasingly popular with help of information technology and internet of things to the devices. However, applying HBPM to daily clinical practices is still challenging, because most patients with hypertension are in age groups not familiar to digital devices and internet and high BP criteria using average home BP values are often useless in outpatient clinics without easily accessible average BP calculation tools. Therefore, we developed a simple and straightforward method to interpret HBPM through counts of BP ≥135/85 mmHg.

Methods

We simulated 400 cases of HBPM using a random number generator function in statistical software. The simulated average home systolic BP (SBP) and its standard deviation (SD) were 125±15 mmHg and 12±5 mmHg and the number of HBP readings was 24 times. The simulated diastolic BP (DBP) was randomly selected to 50–75% of the SBP. The validation of the binary interpretation method was conducted using actual HBPM data from 386 subjects in a rural area of South Korea. Receiver operating characteristics curve analysis was conducted, and linear regression and logarithmic models were fitted between the numbers of home BP ≥135/85 mmHg and mean BP. Hypertension was defined with average home BP ≥135/85 mmHg.

Results

In the simulated cohort, hypertension was presented in 197 cases (49.3%). The C-index of the numbers of BP readings ≥135/85 mmHg was 0.994 (95% confidence interval [CI] 0.990–0.998), and ≥12 of 24 BP readings ≥135/85 mmHg showed a sensitivity of 95.4%, a specificity of 95.1% and an accuracy of 95.3% for the diagnosis of hypertension. In validation cohort, the numbers of home BP measurements varied from 8 to 81 times. The validation cohort similarly showed that the C-index of the ratio between the number of high BP readings (≥135/85 mmHg) to the number of BP measurements (R-NHBP/NBP) was 0.985 (95% CI, 0.976–0.994) and the best accuracy was shown at R-NHBP/NBP of ≥0.45. R-NHBP/NBP of ≥0.5 showed a sensitivity of 0.957, a specificity of 0.907 and an accuracy of 0.927. The accuracy of the R-NHBP/NBP of ≥0.5 decreased as SD and the range of SBP increased, whereas it did not change with the number of measurements (Figure 1). R-NHBP/NBP <0.2 predicted normotension and R-NHBP/NBP >0.8 predicted hypertension in 95% confidence. Mean widths of the 95 prediction intervals for the average SBP and DBP were 18.2 mmHg and 12.6 mmHg, respectively (Figure 2).

Conclusion

Counting the number of BP ≥135/85 mmHg can provide accurate assessments for the BP levels. R-NHBP/NBP of ≥0.5 is a simple and accurate marker of high BP in HBPM, and R-NHBP/NBP could be a useful tool to assess BP levels in patients practicing HBPM.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Retrograde transvenous obliteration for the prevention of variceal rebleeding in patients with hepatocellular carcinoma: a multicentre retrospective study

AIM

To evaluate the effectiveness and safety of retrograde transvenous obliteration (RTO) for the prevention of variceal rebleeding variceal rebleeding in patients with hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

This multicentre retrospective study enrolled 79 patients with HCC who underwent RTO for the prevention of variceal rebleeding. Successful occlusion of the gastrorenal shunt and obliteration of the gastric varices were achieved in 74 patients, with a technical success rate of 93.7%. Of the remaining 74 patients (mean age, 64.9±10.3 years; 56 men), 66 (90.4%) had gastroesophageal varices and seven (9.6%) had isolated gastric varices. Thirty-two patients (43.8%) underwent balloon-occluded RTO, 40 patients (54.8%) underwent plug-assisted RTO, and one patient (1.4%) underwent coil-assisted RTO. No patients had major procedural complications.

RESULTS

Rebleeding occurred in seven patients (9.6%) during the follow-up period. The 6-week and 1-year actuarial probabilities of patients remaining free of rebleeding were 90.8±3.6% and 88.6±4.1%, respectively. The median survival was 12.6 (95% confidence interval [CI] 8-17.3) months. The 6-week, 1-year, and 3-year actuarial probabilities of survival were 83.2±4.4%, 51.1±6.6%, and 32.7±7%, respectively. New or worsening ascites and oesophageal varices occurred in 12 (16.4%) and 13 patients (17.8%), respectively, during the follow-up period. Overt hepatic encephalopathy occurred in one patient (1.4%) during the follow-up period. The Child-Pugh score remained comparable to that at baseline at 1 and 3 months.

CONCLUSION

RTO was effective and safe in preventing variceal rebleeding in patients with HCC.

Safety and efficacy of transarterial embolisation for treatment of dorsal pancreatic artery haemorrhage

AIM

To evaluate the safety and efficacy of transarterial embolisation (TAE) of dorsal pancreatic artery (DPA) haemorrhage.

MATERIALS AND METHODS

Nineteen consecutive patients (M:F = 16:3, mean age 59.6 years) who underwent TAE of DPA in three tertiary medical centres between January 2001 to January 2020 were reviewed retrospectively. Angiographic features and the technical and clinical outcomes of TAE were analysed.

RESULTS

The clinical presentations were a bloody drain from the Jackson-Pratt drainage tube (n=8), melaena (n=7), abdominal pain (n=4), and haematochezia (n=3). Angiographic findings included pseudoaneurysm (n=14), contrast media extravasation (n=4), or abrupt cut-off of the arterial branch (n=1). The NBCA (N-butyl-cyanoacrylate; n=4), microcoils (n=4), and a combination of these agents (n=7) were used as embolic agents. The most common origin of the DPA in the present study cohort was the splenic artery (n=7), followed by the coeliac trunk (n=4), common hepatic artery (n=4), and superior mesenteric artery (n=4). Technical and clinical success rates were 100% and 84.2% (16/19), respectively. Of the three clinically unsuccessful cases, two patients were revealed to have newly developed bleeding from another artery. The other patient expired 1 day after the TAE procedure due to a progression of hepatic failure. In one patient, an asymptomatic non-target embolisation occurred in the right posterior tibial artery as a procedure-related complication. No major complications were observed.

CONCLUSION

TAE is safe and effective for the management of bleeding from the DPA. It is important to be aware of the DPA as a potential bleeding source, including the relevant clinical characteristics.

Low-dose CT angiography of the lower extremities: a comparison study of image quality and radiation dose

AIM

To investigate the image quality and radiation dose of ultralow-dose (ULD) and low-dose (LD) lower-extremity computed tomography (CT) angiography (LE-CTA) using the advanced modelled iterative reconstruction (ADMIRE) algorithm to detect peripheral arterial disease (PAD) in comparison with standard-dose (SD) CT.

MATERIALS AND METHODS

One hundred and seven consecutive patients were examined using LE-CTA at 70 kVp and a dual-source scanner to achieve three image sets using 30% (ULD), 70% (LD), and 100% (SD) tube loads. Qualitative analysis was conducted by examining the three image sets for overall quality. The image quality of arterial segments was analysed by two independent readers. In addition, the CT dose index (CTDI_vol) was measured in the three image sets.

RESULTS

The mean overall quality scores were 3.4±0.6 for ULD CT, 3.9±0.3 for LD CT, and 3.9±0.2 for SD CT. Both readers scored the arterial segments as 2-4 (adequate-excellent) in the three image sets. In addition, 89.4% (93/104) and 54.8% (57/104) segments of PAD with calcified plaques were scored 4 between SD and LD CT and between SD and ULD CT, respectively, and 45.2% (47/104) segments had a lower score by one point in ULD CT compared with SD CT. The mean CTDI_vol was 4.1±1.1 mGy for SD CT, 2.9±0.8 mGy for LD CT, and 1.2±0.3 mGy for ULD CT.

CONCLUSIONS

LD/ULD CT at 70 kVp using ADMIRE reconstruction enables a reduction in the radiation dose while enabling adequate evaluation or follow-up of PAD based on LE-CTA.

Ulmus parvifolia Modulates Platelet Functions and Inhibits Thrombus Formation by Regulating Integrin αIIbβ3 and cAMP Signaling

Background

The prevalence of cardiovascular diseases (CVDs) is increasing at a high rate, and the available treatment options, sometimes, have complications which necessitates the need to develop safer and efficacious approaches. Ethnomedicinal applications reportedly reduce CVD risk. Ulmus parvifolia Jacq. (Ulmaceae) commonly known as Chinese Elm or Lacebark Elm, is native to China, Japan, and Korea. It exhibits anti-inflammatory, antiviral, and anticancer properties, but its anti-platelet properties have not yet been elucidated.

Purpose

To investigate the pharmacological anti-platelet and anti-thrombotic effects of U. parvifolia bark extract.

Study Design and Methods

Human and rat washed platelets were prepared; light transmission aggregometry and scanning electron microscopy was performed to assess platelet aggregation and the change in platelet shape, respectively. Intracellular calcium mobilization, ATP release, and thromboxane-B2 production were also measured. Integrin α_IIbβ₃ activation was analyzed in terms of fibrinogen binding, fibronectin adhesion, and clot retraction. The expression of MAPK, Src, and PI3K/Akt pathway proteins was examined. Cyclic nucleotide signaling pathway was evaluated via cAMP elevation and VASP phosphorylation. Anti-thrombotic activity of the extract was evaluated in vivo using an arteriovenous shunt rat model, whereas its effect on hemostasis in mice was assessed via bleeding time assay.

Results

U. parvifolia extract significantly inhibited human and rat platelet aggregation in a dose-dependent manner along with inhibition of calcium mobilization, dense granule secretion, and TxB2 production. Integrin α_IIbβ₃ mediated inside-out and outside-in signaling events, as evidenced by the inhibition of fibrinogen binding, fibronectin adhesion, and clot retraction. The extract significantly reduced phosphorylation of Src, MAPK (ERK, JNK, and p38^MAPK), and PI3K/Akt pathway proteins. Cyclic-AMP levels were elevated in U. parvifolia-treated platelets, while PKAαβγ and VASP^ser157 phosphorylation was enhanced. U. parvifolia reduced thrombus weight in rats and moderately increased bleeding time in mice.

Conclusion

U. parvifolia modulates platelet responses and inhibit thrombus formation by regulating integrin α_IIbβ₃ mediated inside-out and outside-in signaling events and cAMP signaling pathway.

Supramolecular Regulation of Polydopamine Formation by Amyloid Fibers

Polydopamine (PD) and melanin species are chemically complex systems, the formation and properties of which are incompletely understood. Inspired by the role of functional amyloids in melanin biosynthesis, this paper examines the influences of the supramolecular structure of amyloids on oxidative polymerization of dopamine. Kinetic analyses on the formation of PD species in the presence of hen egg white lysozyme (HEWL) fibers or soluble HEWL revealed that both forms gave rise to the total quantity of PD species, but the rate of their formation could be accelerated only by the amyloid form. PD species formed with HEWL fibers showed a morphology of bundled fibers, whereas those with soluble HEWL had a mesh-like structure. Amyloid fibers of recombinant Pmel17 had properties similar to those of HEWL fibers in modulating PD formation. The results presented here suggest how nature designs functionality with an amyloid structure and can help understand and engineer chemistries of other functional amyloids.

Radiomics Study of Thyroid Ultrasound for Predicting BRAF Mutation in Papillary Thyroid Carcinoma: Preliminary Results

BACKGROUND AND PURPOSE

It is not known how radiomics using ultrasound images contribute to the detection of BRAF mutation. This study aimed to evaluate whether a radiomics study of gray-scale ultrasound can predict the presence or absence of B-Raf proto-oncogene, serine/threonine kinase (BRAF) mutation in papillary thyroid cancer.

MATERIALS AND METHODS

The study retrospectively included 96 thyroid nodules that were surgically confirmed papillary thyroid cancers between January 2012 and June 2013. BRAF mutation was positive in 48 nodules and negative in 48 nodules. For analysis, ROIs from the nodules were demarcated manually on both longitudinal and transverse sonographic images. We extracted a total of 86 radiomics features derived from histogram parameters, gray-level co-occurrence matrix, intensity size zone matrix, and shape features. These features were used to build 3 different classifier models, including logistic regression, support vector machine, and random forest using 5-fold cross-validation. The performance including accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve, of the different models was evaluated.

RESULTS

The incidence of high-suspicion nodules diagnosed on ultrasound was higher in the BRAF mutation-positive group than in the mutation-negative group (P  =  .004). The radiomics approach demonstrated that all classification models showed moderate performance for predicting the presence of BRAF mutation in papillary thyroid cancers with an area under the curve value of 0.651, accuracy of 64.3%, sensitivity of 66.8%, and specificity of 61.8%, on average, for the 3 models.

CONCLUSIONS

Radiomics study using thyroid sonography is limited in predicting the BRAF mutation status of papillary thyroid carcinoma. Further studies will be needed to validate our results using various diagnostic methods.

Interventional treatment of arterial injury during blind central venous catheterisation in the upper thorax: experience from two centres

AIM

To evaluate the safety and clinical efficacy of interventional treatment for arterial injury during blind, central venous catheterisation in the upper thorax at two tertiary medical centres.

MATERIALS AND METHODS

Eighteen consecutive patients (37-81 years; M:F=8:10) who underwent interventional treatment for the arterial injuries that occurred during central venous catheterisation without any imaging guidance between November 2007 and December 2018 were included. Clinical data, angiographic findings, detailed interventional procedures, and technical and clinical outcomes were analysed retrospectively.

RESULTS

Arterial injury sites were the subclavian artery/branches (n=12), axillary artery/branches (n=2), and common carotid artery (n=4). The target vein was not correlated with the corresponding artery/branches in eight patients (44.4%); internal jugular vein to subclavian artery branches. Angiographic findings were pseudoaneurysm (66.7%, 12/18), contrast medium extravasation (22.2%, 4/18), or both (11.1%, n=2). A stent graft was inserted for the main trunk injuries in nine patients, with (n=2) or without (n=7) prior arterial branch embolisation to prevent potential endoleak, while embolisation for the arterial branch injuries was performed in nine patients. Direct percutaneous access with thrombin injection to the pseudoaneurysm or residual arteriovenous fistula was utilised in two. The technical and clinical success rate was 94.4% (17/18) each. There were no procedure-related complications. In one patient without immediate clinical success, there was a persistent pseudoaneurysm after stent graft placement, which was treated with in-stent balloon dilation.

CONCLUSION

Interventional treatment serves as a safe and effective treatment modality for inadvertent arterial injury related to blind, central venous access catheterisation in the upper thorax.

P5298Influence of the changes in body fat on all-cause and cardiovascular mortality in a general population: a report from Ansan-Ansung cohort in the Korean genome environment study

Background

Paradoxical beneficial effects of obesity on all-cause and cardiovascular mortality have been reported in multiple cohort studies based on patients with cardiovascular disease as well as general populations. However, the association between the presence of obesity at baseline and the better survival rates could not be directly interpreted into the beneficial effect of gain in obesity or fatness on the mortality, which makes it difficult to provide any recommendation for the management of obesity. Therefore, we investigated the influence of the changes in body fat on all-cause and cardiovascular mortality in a general population.

Methods

A population-based cohort study has been conducted for 12 years (from 2001 to 2012). A total of 5,259 subjects in whom body compositions using a bio-impedance method were measured at least 2 times during the observational period were included. The causes of death was identified from the nation-wide database in KOSTAT. I20-I82 and R99 in the International Classification of Disease-10 codes were defined as a cardiovascular death. The subjects were evenly divided into 3 groups by the percentages of the changes in body fat (Δ%BF; decreased [Δ%BF <0.0%] vs. increased [Δ%BF 0.0–13.7%] vs. highly increased [Δ%BF ≥13.7%]). Inverse probability of treatment weighting was applied to balance the covariate differences among the groups.

Results

The age was 51.2±8.5 years and 51.6% was male. Median observation duration was 163 (the interquartile range: 157–168) months. The all-cause death and cardiovascular death occurred most frequently in the decreased Δ%BF group and least frequent in the highly increased Δ%BF group in both unweighted and weighted cohort. Multivariate Cox proportional hazard models showed that the risk of all-cause death was lower in the increased and highly increased Δ%BF groups (hazard ratio [HR] 0.61 [0.47–0.80] and 0.24 [0.17–0.34], respectively) and the risk of cardiovascular death was lower in the highly increased Δ%BF group (HR 0.20 [0.08–0.48]), compared to those in the decreased Δ%BF group after adjustment for all covariates including physical activities and the changes in muscle mass. The risk of all-cause death and cardiovascular death linearly decreased with increasing Δ%BF (HR 0.72 [0.67–0.77] and 0.70 [0.60–0.82], respectively).

Conclusion

The increase in body fat is associated with a lower risk of all-cause death and cardiovascular death in a middle-age general population, independently with physical activities and the changes in muscle mass.

P5665The independent effect of insulin resistance on incidence of atrial fibrillation in non-diabetics

Purpose

Patients with diabetes mellitus have an elevated risk of atrial fibrillation (AF). However, whether insulin resistance may elevate risk of AF incidence in non-diabetic is inconsistent. The aim of our study was to verify the association between insulin resistance and incidence of AF in non-diabetics.

Methods

We evaluated population-based cohorts embedded in the Korean Genome Epidemiology Study. Insulin resistance was expressed as Homeostasis Model Assessment for Insulin resistance (HOMA-IR). Baseline data including HOMA-IR and electrocardiography (ECG) were obtained at 2001. Subsequent biennial ECG was performed for identification of AF until 2016.

Results

Among the 8220 participants (46.8% male; median age 49 years), 25 participants had AF (0.3%) at baseline and 101 participants developed AF (1.2%) during follow up of 12 years. In multivariate Cox regression analysis, high HOMA-IR (≥1.4) was significantly associated with incident AF compared with low HOMA-IR (<1.40) (adjusted hazard ratio [HR] 1.9, 95% confidence interval [CI] 1.3–3.0). In subgroup analysis, these association was consistent regardless of obesity (BMI<25; adjust HR 1.8, 95% CI 1.1–3.0, BMI≥25; adjust HR 2.3, 95% CI 1.3–4.0)

Subgroup analysis

Conclusion

Based on prospective cohort study, insulin resistance (HOMA-IR) was associated with AF independently of obesity in non-diabetics.

Osseous versus Nonosseous Spinal Epidural Arteriovenous Fistulas: Experiences of 13 Patients

BACKGROUND AND PURPOSE

Spinal epidural arteriovenous fistulas are rare vascular malformations. We present 13 patients with spinal epidural arteriovenous fistulas, noting the various presenting symptom patterns, imaging findings related to bone involvement, and outcomes.

MATERIALS AND METHODS

Among 111 patients with spinal vascular malformations in the institutional data base from 1993 to 2017, thirteen patients (11.7%) had spinal epidural arteriovenous fistulas. We evaluated presenting symptoms and imaging findings, including bone involvement and mode of treatment. To assess the treatment outcome, we compared initial and follow-up clinical status using the modified Aminoff and Logue Scale of Disability and the modified Rankin Scale.

RESULTS

The presenting symptoms were lower back pain (n = 2), radiculopathy (n = 5), and myelopathy (n = 7). There is overlap of symptoms in 1 patient (No. 11). Distribution of spinal epidural arteriovenous fistulas was cervical (n = 3), thoracic (n = 2), lumbar (n = 6), and sacral (n = 2). Intradural venous reflux was identified in 7 patients with congestive venous myelopathy. The fistulas were successfully treated in all patients who underwent treatment (endovascular embolization, n = 10; operation, n = 1) except 2 patients who refused treatment due to tolerable symptoms. Transarterial glue (n = 7) was used in nonosseous types; and transvenous coils (n = 3), in osseous type. After 19 months of median follow-up, the patients showed symptom improvement after treatment.

CONCLUSIONS

Although presenting symptoms were diverse, myelopathy caused by intradural venous reflux was the main target of treatment. Endovascular treatment was considered via an arterial approach in nonosseous types and via a venous approach in osseous types.

Transcatheter arterial embolization for iatrogenic bleeding after endoscopic ultrasound-guided pancreaticobiliary drainage

PURPOSE

The purpose of this study was to report the incidence of massive bleeding after endoscopic ultrasound-guided transmural pancreaticobiliary drainage (EUS-TPBD) and the clinical outcomes in patients with this condition treated with transcatheter arterial embolization (TAE).

PATIENTS AND METHODS

We performed a 9-year retrospective analysis of 797 EUS-TPBD procedures (excluding gallbladder or pseudocysts) in 729 patients. Among them, twelve (12/729, 1.65%) patients were referred for TAE to manage active bleeding adjacent to the TPBD sites. There were 8 men and 4 women with a mean age of 66.1 years±13.4 (SD) (range: 45-89 years). The clinical and procedure data of these 12 patients were reviewed.

RESULTS

Thirteen TAE procedures in 12 patients were performed. The bleeding sites were the left hepatic artery (n=7), the right hepatic artery (n=3), the left gastric artery (n=1), the left accessory gastric artery (n=1) and gastroduodenal artery (n=1). TAE was performed with gelatin sponge particles (n=1), coil (n=1) and n-butyl-2 cyanoacrylate with/without coils (n=11), with technical and clinical success rates of 100% (13/13) and 85% (11/13), respectively. Re-bleeding following embolization with gelatin sponge particles occurred in one patient. Procedure-related ischemic hepatitis was observed in another patient with pancreatic cancer with portal vein involvement.

CONCLUSION

On the basis of our results, TAE using n-butyl-2 cyanoacrylate seems safe and effective for the treatment of bleeding after EUS-TPBD procedures. When the portal vein is compromised, TAE of the hepatic artery can cause ischemic liver damage.

Electrically controllable THz asymmetric split-loop resonator with an outer square loop based on VO2

In this paper, we propose an asymmetric split-loop resonator with an outer square loop (ASLR-OSL) based on vanadium dioxide (VO₂) which can actively control the transmission characteristics of a terahertz wave while maintaining a high quality factor of the asymmetric split-loop resonator (ASLR) by adding an outer square loop. The proposed ASLR-OSL demonstrated transmission characteristics similar to those of ASLR, and the transmission characteristics of ASLR-OSL were successfully controlled by directly applying a bias voltage. These results show a simple method for imposing active properties on a common metamaterial having a high quality factor by adding a loop structure.

Gintonin modulates platelet function and inhibits thrombus formation via impaired glycoprotein VI signaling

Panax ginseng (P. ginseng), one of the most valuable medicinal plants, is known for its healing and immunobooster properties and has been widely used in folk medicine against cardiovascular diseases, including stroke and heart attack. In this study, we explored the anti-platelet activity of gintonin (a recently discovered non-saponin fraction of ginseng) against agonist-induced platelet activation. In vitro effects of gintonin on agonist-induced human and rat platelet aggregation, granule secretion, integrin α_IIbβ₃ activation, and intracellular calcium ion ([Ca²⁺]_i) mobilization were examined. Western blot analysis and immunoprecipitation techniques were used to estimate the expression of mitogen-activated protein kinases (MAPKs) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) and interaction of glycoprotein VI (GPVI) signaling pathway molecules such as Src family kinases (SFK), tyrosine kinase Syk, and PLCγ2. In vivo effects were studied using acute pulmonary thromboembolism model in mice. Gintonin remarkably inhibited collagen-induced platelet aggregation and suppressed granule secretion, [Ca²⁺]_i mobilization, and fibrinogen binding to integrin α_IIbβ₃ in a dose-dependent manner and clot retraction. Gintonin attenuated the activation of MAPK molecules and PI3K/Akt pathway. It also inhibited SFK, Syk, and PLCγ2 activation and protected mice from thrombosis. Gintonin inhibited agonist-induced platelet activation and thrombus formation through impairment in GPVI signaling molecules, including activation of SFK, Syk, PLCγ2, MAPK, and PI3K/Akt; suggesting its therapeutic potential against platelet related CVD.

Clinical outcomes of 23 patients who had repeat pelvic arterial embolisation for uncontrolled post-partum haemorrhage at a single centre

AIM

To evaluate the safety and efficacy of repeated pelvic arterial embolisation (PAE) for uncontrolled postpartum haemorrhage (PPH) after a single session of PAE and to compare angiographic findings between the two sessions of PAE.

MATERIALS AND METHODS

A total of 23 consecutive patients (age range, 23-44 years) who underwent repeated PAE for uncontrolled PPH between March 2001 and January 2016 in Severance Hospital were reviewed. The interval times between the two sessions of PAE, the angiographic findings, embolic materials, arteries embolised during PAE, and the clinical outcomes were reviewed retrospectively.

RESULTS

Overall clinical success was achieved after repeated PAE in 21 of 23 patients (91.3%). There were no procedure-related, major complications. On angiography, active bleeding from the uterine collateral arteries was more frequently observed in the second session of PAE (p>0.05), and embolisation of the anterior division of the internal iliac artery was significantly higher during the second session of PAE. Use of permanent embolic materials was significantly higher during the second session of PAE. Recanalisation of a previously embolised artery was identified in 14 patients (60.9%) during the second session.

CONCLUSION

Repeated PAE is safe and effective for managing recurrent bleeding after a single session of PAE. Repeated PAE is related to a higher chance of embolisation of the anterior division of the internal iliac artery, with the use of permanent embolic materials. Recanalisation of a previously embolised artery seems to be a principal source of rebleeding during a repeated session of PAE.

Inhibitory effects of thromboxane A2 generation by ginsenoside Ro due to attenuation of cytosolic phospholipase A2 phosphorylation and arachidonic acid release

Background

Thromboxane A₂ (TXA₂) induces platelet aggregation and promotes thrombus formation. Although ginsenoside Ro (G-Ro) from Panax ginseng is known to exhibit a Ca²⁺-antagonistic antiplatelet effect, whether it inhibits Ca²⁺-dependent cytosolic phospholipase A₂ (cPLA_2α) activity to prevent the release of arachidonic acid (AA), a TXA₂ precursor, is unknown. In this study, we attempted to identify the mechanism underlying G-Ro-mediated TXA₂ inhibition.

Methods

We investigated whether G-Ro attenuates TXA₂ production and its associated molecules, such as cyclooxygenase-1 (COX-1), TXA₂ synthase (TXAS), cPLA_2α, mitogen-activated protein kinases, and AA. To assay COX-1 and TXAS, we used microsomal fraction of platelets.

Results

G-Ro reduced TXA₂ production by inhibiting AA release. It acted by decreasing the phosphorylation of cPLA_2α, p38-mitogen-activated protein kinase, and c-Jun N-terminal kinase1, rather than by inhibiting COX-1 and TXAS in thrombin-activated human platelets.

Conclusion

G-Ro inhibits AA release to attenuate TXA₂ production, which may counteract TXA₂-associated thrombosis.

Histogram analysis of greyscale sonograms to differentiate between the subtypes of follicular variant of papillary thyroid cancer

AIM

To evaluate the diagnostic value of histogram analysis using ultrasound (US) to differentiate between the subtypes of follicular variant of papillary thyroid carcinoma (FVPTC).

MATERIALS AND METHODS

The present study included 151 patients with surgically confirmed FVPTC diagnosed between January 2014 and May 2016. Their preoperative US features were reviewed retrospectively. Histogram parameters (mean, maximum, minimum, range, root mean square, skewness, kurtosis, energy, entropy, and correlation) were obtained for each nodule.

RESULTS

The 152 nodules in 151 patients comprised 48 non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTPs; 31.6%), 60 invasive encapsulated FVPTCs (EFVPTCs; 39.5%), and 44 infiltrative FVPTCs (28.9%). The US features differed significantly between the subtypes of FVPTC. Discrimination was achieved between NIFTPs and infiltrative FVPTC, and between invasive EFVPTC and infiltrative FVPTC using histogram parameters; however, the parameters were not significantly different between NIFTP and invasive EFVPTC.

CONCLUSION

It is feasible to use greyscale histogram analysis to differentiate between NIFTP and infiltrative FVPTC, but not between NIFTP and invasive EFVPTC. Histograms can be used as a supplementary tool to differentiate the subtypes of FVPTC.

ErbB4 signaling in dopaminergic axonal projections increases extracellular dopamine levels and regulates spatial/working memory behaviors

Genetic variants of Neuregulin 1 (NRG1) and its neuronal tyrosine kinase receptor ErbB4 are associated with risk for schizophrenia, a neurodevelopmental disorder characterized by excitatory/inhibitory imbalance and dopamine (DA) dysfunction. To date, most ErbB4 studies have focused on GABAergic interneurons in the hippocampus and neocortex, particularly fast-spiking parvalbumin-positive (PV+) basket cells. However, NRG has also been shown to modulate DA levels, suggesting a role for ErbB4 signaling in dopaminergic neuron function. Here we report that ErbB4 in midbrain DAergic axonal projections regulates extracellular DA levels and relevant behaviors. Mice lacking ErbB4 in tyrosine hydroxylase-positive (TH+) neurons, but not in PV+ GABAergic interneurons, exhibit different regional imbalances of basal DA levels and fail to increase DA in response to local NRG1 infusion into the dorsal hippocampus, medial prefrontal cortex and dorsal striatum measured by reverse microdialysis. Using Lund Human Mesencephalic (LUHMES) cells, we show that NRG/ErbB signaling increases extracellular DA levels, at least in part, by reducing DA transporter (DAT)-dependent uptake. Interestingly, TH-Cre;ErbB4^f/f mice manifest deficits in learning, spatial and working memory-related behaviors, but not in numerous other behaviors altered in PV-Cre;ErbB4^f/f mice. Importantly, microinjection of a Cre-inducible ErbB4 virus (AAV-ErbB4.DIO) into the mesencephalon of TH-Cre;ErbB4^f/f mice, which selectively restores ErbB4 expression in DAergic neurons, rescues DA dysfunction and ameliorates behavioral deficits. Our results indicate that direct NRG/ErbB4 signaling in DAergic axonal projections modulates DA homeostasis, and that NRG/ErbB4 signaling in both GABAergic interneurons and DA neurons contribute to the modulation of behaviors relevant to psychiatric disorders.

Liver-Wrapping, Nitric Oxide-Releasing Nanofiber Downregulates Cleaved Caspase-3 and Bax Expression on Rat Hepatic Ischemia-Reperfusion Injury

BACKGROUND

Hepatic ischemia-reperfusion injury (IRI) is an important determinant of the outcome of hepatic surgery, including re-section and transplantation. Previous studies have shown that nitric oxide (NO) has a protective effect against IRI. Therefore, many studies have examined methods for supplying NO. In this study, we investigated the effect of NO-releasing nanofibers on hepatic IRI in a rat model.

METHODS

Male Sprague-Dawley rats were divided into 4 groups: control, IRI only (n = 3); group 1, hepatic IRI and liver-wrapping with nanofiber lacking NO (n = 4); group 2, hepatic IRI and liver-wrapping with NO rapid-releasing nanofiber (n = 4); and group 3, hepatic IRI and liver-wrapping with NO slow-releasing nanofiber (n = 5).

RESULTS

The levels of aspartate aminotransferase and alanine aminotransferase were not significantly different between groups. On the basis of Western blots, Bax/β-actin levels were significantly lower in group 2 than in group 3 (P < .01). Cleaved Caspase-3/β-actin levels were significantly lower in group 2 than in the control, group 1, and group 3 (P < .05, .01, and .01, respectively). However, there were no significant differences in Bcl-2/β-actin between groups.

CONCLUSIONS

The liver-wrapping NO rapid-releasing nanofiber downregulated cleaved Caspase-3 and Bax expression. It has a protective effect by reducing apoptosis in hepatic IRI in rats.

Altered expression of histamine signaling genes in autism spectrum disorder

The histaminergic system (HS) has a critical role in cognition, sleep and other behaviors. Although not well studied in autism spectrum disorder (ASD), the HS is implicated in many neurological disorders, some of which share comorbidity with ASD, including Tourette syndrome (TS). Preliminary studies suggest that antagonism of histamine receptors 1-3 reduces symptoms and specific behaviors in ASD patients and relevant animal models. In addition, the HS mediates neuroinflammation, which may be heightened in ASD. Together, this suggests that the HS may also be altered in ASD. Using RNA sequencing (RNA-seq), we investigated genome-wide expression, as well as a focused gene set analysis of key HS genes (HDC, HNMT, HRH1, HRH2, HRH3 and HRH4) in postmortem dorsolateral prefrontal cortex (DLPFC) initially in 13 subjects with ASD and 39 matched controls. At the genome level, eight transcripts were differentially expressed (false discovery rate <0.05), six of which were small nucleolar RNAs (snoRNAs). There was no significant diagnosis effect on any of the individual HS genes but expression of the gene set of HNMT, HRH1, HRH2 and HRH3 was significantly altered. Curated HS gene sets were also significantly differentially expressed. Differential expression analysis of these gene sets in an independent RNA-seq ASD data set from DLPFC of 47 additional subjects confirmed these findings. Understanding the physiological relevance of an altered HS may suggest new therapeutic options for the treatment of ASD.

What Is the Ideal Core Number for Ultrasonography-Guided Thyroid Biopsy of Cytologically Inconclusive Nodules?

BACKGROUND AND PURPOSE

Core needle biopsy of the thyroid under ultrasonographic guidance provides a larger tissue sample and may facilitate a more precise histologic diagnosis, reducing the need for repetitive fine-needle aspiration or a diagnostic operation. However, there is no consensus regarding the ideal number of specimens to be obtained for ultrasonography-guided core needle biopsy. The aim of this study was to decide the ideal core number for ultrasonography-guided core needle biopsy of cytologically inconclusive nodules.

MATERIALS AND METHODS

Sixty consecutive biopsies were performed in 60 thyroid nodules with Bethesda Category I or III cytology. Three biopsy cores were obtained for each thyroid nodule. The first biopsy specimens were taken from the nodule, while the second and third specimens obtained included the nodular tissue, nodular capsule, and surrounding parenchyma. Diagnostic ability was evaluated according to the following: protocol A, first specimen; protocol B, first and second specimens; and protocol C, all specimens. The McNemar test was used for statistical analysis.

RESULTS

Of the 60 nodules, diagnostic ability was achieved in 41 nodules (68%) with protocol A, in 56 nodules (93%) with protocol B, and in 58 nodules (97%) with protocol C. The diagnostic ability of protocols B and C was significantly higher than that of protocol A (all P values < .001). However, the diagnostic ability of protocol B was not significantly different from that of protocol C.

CONCLUSIONS

Ultrasonography-guided core needle biopsy for cytologically inconclusive thyroid nodules should obtain at least 2 core specimens with intranodular and capsule targets.

Antiplatelet and antithrombotic effects of cordycepin-enriched WIB-801CE from Cordyceps militaris ex vivo, in vivo, and in vitro

BACKGROUND

A species of the fungal genus Cordyceps has been used as a complementary and alternative medicine of traditional Chinese medicine, and its major component cordycepin and cordycepin-enriched WIB-801CE are known to have antiplatelet effects in vitro. However, it is unknown whether they have also endogenous antiplatelet and antithrombotic effects. In this study, to resolve these doubts, we prepared cordycepin-enriched WIB-801CE, an ethanol extract from Cordyceps militaris-hypha, then evaluated its ex vivo, in vivo, and in vitro antiplatelet and antithrombotic effects.

METHODS

Ex vivo effects of WIB-801CE on collagen- and ADP-induced platelet aggregation, serotonin release, thromboxane A2 (TXA2) production and its associated activities of enzymes [cyclooxygenase-1 (COX-1), TXA2 synthase (TXAS)], arachidonic acid (AA) release and its associated phosphorylation of phospholipase Cβ3, phospholipase Cγ2 or cytosolic phospholipase A2, mitogen-activated protein kinase (MAPK) [p38 MAPK, extracellular signal-regulated kinase (ERK)], and blood coagulation time in rats were investigated. In vivo effects of WIB-801CE on collagen plus epinephrine-induced acute pulmonary thromboembolism, and tail bleeding time in mice were also inquired. In vitro effects of WIB-801CE on cytotoxicity, and fibrin clot retraction in human platelets, and nitric oxide (NO) production in RAW264.7 cells or free radical scavenging activity were studied.

RESULTS

Cordycepin-enriched WIB-801CE inhibited ex vivo platelet aggregation, TXA2 production, AA release, TXAS activity, serotonin release, and p38 MAPK and ERK2 phosphorylation in collagen- and ADP-activated rat platelets without affecting blood coagulation. Furthermore, WIB-801CE manifested in vivo inhibitory effect on collagen plus epinephrine-induced pulmonary thromboembolism mice model. WIB-801CE inhibited in vitro NO production and fibrin clot retraction, but elevated free radical scavenging activity without affecting cytotoxicity against human platelets.

CONCLUSION

WIB-801CE inhibited collagen- and ADP-induced platelet activation and its associated thrombus formation ex vivo and in vivo. These were resulted from down-regulation of TXA2 production and its related AA release and TXAS activity, and p38MAPK and ERK2 activation. These results suggest that WIB-801CE has therapeutic potential to treat platelet activation-mediated thrombotic diseases in vivo.

Highly efficient terahertz radiation from a thin foil irradiated by a high-contrast laser pulse

Radially polarized intense terahertz (THz) radiation behind a thin foil irradiated by ultrahigh-contrast ultrashort relativistic laser pulse is recorded by a single-shot THz time-domain spectroscopy system. As the thickness of the target is reduced from 30 to 2 µm, the duration of the THz emission increases from 5 to over 20 ps and the radiation energy increases dramatically, reaching ∼10.5mJ per pulse, corresponding to a laser-to-THz radiation energy conversion efficiency of 1.7%. The efficient THz emission can be attributed to reflection (deceleration and acceleration) of the laser-driven hot electrons by the target-rear sheath electric field. The experimental results are consistent with that of a simple model as well as particle-in-cell simulation.

Accuracy of Xpert(®) MTB/RIF assay compared with AdvanSure™ TB/NTM real-time PCR using bronchoscopy specimens

BACKGROUND

The performance of Xpert(®) MTB/RIF assay, an automated nucleic acid amplification test (NAAT) that was developed for the detection of tuberculosis (TB), has been evaluated in various clinical settings. However, few studies have compared Xpert with other NAATs, especially its performance using lower respiratory tract specimens (LRTS).

OBJECTIVE

To compare the practical diagnostic performance of the Xpert assay with that of the AdvanSure™ TB/NTM RT-PCR kit in the detection of pulmonary TB (PTB), using LRTS obtained through bronchoscopy.

RESULTS

Of 249 patients included, 105 had culture-confirmed PTB. Using culture as reference, the overall sensitivity of Xpert and AdvanSure was respectively 92.4% and 83.8%. When acid-fast bacilli smear results were taken into consideration, the sensitivity of Xpert for smear-positive and smear-negative LRTS was respectively 100% and 88.9%, while that of the AdvanSure was 100% and 76.4%. Xpert showed better results than AdvanSure in terms of sensitivity in smear-negative LRTS (P = 0.012), but no difference in smear-positive LRTS.

CONCLUSIONS

Xpert may be advantageous in the detection of PTB using LRTS, particularly in low microbiological burden settings.

Covered airway stent placement for malignant tracheobronchial strictures in patients with an endotracheal tube

AIM

To evaluate the technical feasibility and safety of covered airway stent placement for malignant tracheobronchial strictures in patients with an endotracheal tube.

MATERIALS AND METHODS

Data regarding retrievable, expandable, metal stent placement under fluoroscopic guidance in 20 patients with an endotracheal tube inserted for malignant tracheobronchial strictures were retrospectively analysed. The clinical effectiveness was assessed using the following variables: technical and clinical success; procedure and stent-related complications; and duration of intubation following stent placement.

RESULTS

Stent placement was technically successful in all 20 patients (100%), and with 19 of the 20 patients (95%) showing symptomatic improvement within 5 days. The endotracheal tube could be removed during (n=7) or after (n=12) stent placement, and the mean duration of intubation following stent placement was 1.4 days (range 0-3 days). One patient could not have his endotracheal tube removed and he died 9 days following stent placement in an intubated state. There were no procedure-related complications. Stent-related complications in three patients included partial (n=2) and complete (n=1) stent migration, all of which were managed with placement of a second stent (n=2) or stent removal and placement of a second stent (n=1).

CONCLUSION

Covered airway stent placement under fluoroscopic guidance in patients with an endotracheal tube inserted for malignant tracheobronchial strictures, is both technically feasible and safe.

Clinical importance of inflammatory facet joints of the spine in ankylosing spondylitis: a magnetic resonance imaging study

OBJECTIVES

The aims of this study were to assess the reliability of a novel magnetic resonance imaging (MRI) scoring system for inflammatory lesions of facet joints and to clarify the clinical significance of facet joint inflammation in ankylosing spondylitis (AS).

METHOD

A total of 53 AS patients (45 males, 84.9%) were assessed for active inflammatory lesions involving the facet joints, as indicated by bone marrow oedema, at 23 discovertebral units (DVUs) between C2 and S1 using a novel scale, the AS Activity of the Facet joint (ASAFacet). The reliability of the ASAFacet was evaluated using intraclass correlation coefficients (ICCs) and Bland-Altman plots.

RESULTS

ICC values for the ASAFacet scores were 0.857 [95% confidence interval (CI) 0.741-0.919] for inter-observer and 0.941 (95% CI 0.873-0.969) for intra-observer reliability. Inflammatory activity scores in facet joints were evenly distributed at all spine levels (p = 0.294 for ASAFacet), whereas vertebral body inflammation was more prominent in the thoracic spine than in the cervical and lumbar spine [p < 0.001 for the AS spine MRI activity (ASspiMRI-a) score, p = 0.002 for the Berlin method, and p < 0.001 for the Spondyloarthritis Research Consortium of Canada (SPARCC) MRI index]. ASAFacet scores were closely associated with erythrocyte sediment rate (ESR) and C-reactive protein (CRP) levels (p < 0.05, respectively). Patients with peripheral arthritis had fewer lesions involving the vertebral bodies or facet joints than patients without peripheral arthritis (p < 0.001 for the four different MRI activity indexes).

CONCLUSIONS

This study suggests that recognition of facet joint inflammation has the potential to contribute to our understanding of clinical outcomes in AS.

Modified Core Biopsy Technique to Increase Diagnostic Yields for Well-Circumscribed Indeterminate Thyroid Nodules: A Retrospective Analysis

BACKGROUND AND PURPOSE

The results of conventional core biopsy for some thyroid nodules with indeterminate cytology have still remained indeterminate. The aim of this study was to evaluate whether the ultrasonography-guided core needle biopsy technique containing the nodule, capsular portion, and surrounding parenchyma was more effective than a conventional method in enhancing diagnostic yield for circumscribed solid thyroid nodules without malignant sonographic features.

MATERIALS AND METHODS

This retrospective comparative study evaluated 26 thyroid nodules in 26 consecutive patients between 2006 and 2010. They were biopsied by using a conventional method, and 61 nodules from 60 patients were biopsied by using a modified ultrasonography-guided core needle biopsy technique in 2013. The patients enrolled in this study presented with circumscribed solid thyroid nodules without malignant sonographic features, classified as nondiagnostic or atypia/follicular lesions of undetermined significance at previous cytology. The ultrasonography-guided core needle biopsy results of the 2 groups were compared.

RESULTS

The rate of inconclusive ultrasonography-guided core needle biopsy results was 34.6% (9/26) in the conventional group and 11.4% (7/61) in the modified technique group (P = .018). There was no significant difference in the mean size of the nodules between the 2 groups (P = .134). The malignancy rate was 33% (3/9) for the conventional group and 52% (27/52) for the modified technique group (P = .473). The most common malignant pathology was a follicular variant of papillary thyroid carcinoma and follicular adenoma was the most common benign lesion.

CONCLUSIONS

For circumscribed solid nodules without malignant sonographic features with indeterminate cytology, the ultrasonography-guided core needle biopsy technique containing the nodule, capsular portion, and surrounding parenchyma is more effective in diagnostic yield compared with a conventional method that biopsies the intranodular portion.

Vasodilator-stimulated phosphoprotein-phosphorylation by ginsenoside Ro inhibits fibrinogen binding to αIIb/β3 in thrombin-induced human platelets

BACKGROUND

Glycoprotein IIb/IIIa (αIIb/β₃) is involved in platelet adhesion, and triggers a series of intracellular signaling cascades, leading to platelet shape change, granule secretion, and clot retraction. In this study, we evaluated the effect of ginsenoside Ro (G-Ro) on the binding of fibrinogen to αIIb/β₃.

METHODS

We investigated the effect of G-Ro on regulation of signaling molecules affecting the binding of fibrinogen to αIIb/β₃, and its final reaction, clot retraction.

RESULTS

We found that G-Ro dose-dependently inhibited thrombin-induced platelet aggregation and attenuated the binding of fibrinogen to αIIb/β₃ by phosphorylating cyclic adenosine monophosphate (cAMP)-dependently vasodilator-stimulated phosphoprotein (VASP; Ser¹⁵⁷). In addition, G-Ro strongly abrogated the clot retraction reflecting the intensification of thrombus.

CONCLUSION

We demonstrate that G-Ro is a beneficial novel compound inhibiting αIIb/β₃-mediated fibrinogen binding, and may prevent platelet aggregation-mediated thrombotic disease.

NAMPT suppresses glucose deprivation-induced oxidative stress by increasing NADPH levels in breast cancer

Nicotinamide phosphoribosyltransferase (NAMPT) is a rate-limiting enzyme involved in NAD+ biosynthesis. Although NAMPT has emerged as a critical regulator of metabolic stress, the underlying mechanisms by which it regulates metabolic stress in cancer cells have not been completely elucidated. In this study, we determined that breast cancer cells expressing a high level of NAMPT were resistant to cell death induced by glucose depletion. Furthermore, NAMPT inhibition suppressed tumor growth in vivo in a xenograft model. Under glucose deprivation conditions, NAMPT inhibition was found to increase the mitochondrial reactive oxygen species (ROS) level, leading to cell death. This cell death was rescued by treatment with antioxidants or NAD+. Finally, we showed that NAMPT increased the pool of NAD+ that could be converted to NADPH through the pentose phosphate pathway and inhibited the depletion of reduced glutathione under glucose deprivation. Collectively, our results suggest a novel mechanism by which tumor cells protect themselves against glucose deprivation-induced oxidative stress by utilizing NAMPT to maintain NADPH levels.

Bleeding after dilatation and curettage: the efficacy of transcatheter uterine artery embolisation

AIM

To evaluate safety and clinical outcomes of uterine artery embolisation (UAE) for bleeding after dilatation and curettage (D&C) performed for abortion or termination.

MATERIALS AND METHODS

The outcomes were analysed in 11 patients who underwent UAE for bleeding after D&C for missed abortions (n=8), caesarean scar pregnancies (n=2), or planned termination (n=1) between October 2001 and December 2013. Angiograms and medical records were retrospectively reviewed in order to obtain the patients' baseline characteristics, technical/clinical success rate, complications, and follow-up data regarding menstruation.

RESULTS

Technical success, defined as successful catheterisation of both uterine arteries with embolisation to haemostasis, was 100%, whereas clinical success, defined as cessation of bleeding after the initial session of UAE and without the need for additional UAE or surgery for the purpose of haemostasis, was 81.8% (nine of 11). In the two patients with clinical failure due to recurrent vaginal bleeding after UAE, one patient underwent repeat UAE and showed a successful outcome, whilst the other patient required hysterectomy with pathological results of placenta increta. Two other patients underwent hysterectomy for placenta percreta or hydatidiform mole-mimicking remnant placenta. None of the patients included in the present series had procedure-related complications. Menstruation resumed in all eight patients with an intact uterus during the mean follow-up period.

CONCLUSION

UAE may be a safe and effective treatment for bleeding after D&C, especially for women who wish to preserve their fertility; however, hysterectomy may be indicated for patients with a placental abnormality.