Percutaneous coronary intervention in patients with acute coronary syndrome in Chinese Military Hospitals, 2011-2014: a retrospective observational study of a national registry

OBJECTIVES

Interventional treatment of patients with acute coronary syndrome (ACS) is surging dramatically in China in recent years, whereas nationwide assessments of the quality of percutaneous coronary intervention (PCI) procedural performance and outcomes are scarce. We aimed to provide an updated and real-world overview of the performance of PCI in patients with ACS since 2011 in China after the China PEACE study from 2001 to 2011.

METHODS

In this cross-sectional study, data were extracted from the National Registry of Cardiovascular Intervention in Military Hospitals database to create a national sample of 144 659 patients with ACS undergoing PCI at 117 military hospitals in all regions of China from calendar years 2011-2014. Patient characteristics, procedural performance, PCI outcomes and adverse events and temporal changes were analysed.

RESULTS

During 2011-2014, patients with ACS undergoing PCI increased dramatically. Small numbers of high-volume hospitals performed the majority of PCI procedures. However, only half of these patients were adequately covered and proportions for the use of assisted devices and novel medications were relatively small. Radial artery access was still increasing with time. Primary PCIs were performed on 45.4% ST-segment elevation myocardial infarction patients with PCI procedures. 3.8% lesion vessels involve left main artery. Implanted stents, the overall complications and in-hospital mortality were decreasing remarkably.

CONCLUSIONS

In Chinese military hospitals, interventional resources were limited with great regional disparities, there are still gaps to be filled to better serve patients with ACS. Our findings can serve as an indispensable supplement to a more comprehensive understanding of the practice of contemporary cardiac intervention in China.

Oncolytic Adenovirus Harboring Interleukin-24 Improves Chemotherapy for Advanced Prostate Cancer

PURPOSE

Oncolytic adenoviruses emerge as new agents for cancer therapy. This study aimed to investigate the synergistic anti-tumor activity of oncolytic adenovirus armed with IL-24 (ZD55-IL-24) and docetaxel (DTX) on advanced prostate cancer in vitro and in vivo.

METHODS

DU145 prostate cancer cells or nude mice xenografted with DU145 prostate cancer cells were treated by ZD55-IL-24 and DTX alone or in combination.

RESULTS

DTX did not affect ZD55-IL-24 replication and IL-24 expression in DU145 cells. In vitro, the combination of ZD55-IL-24 and DTX showed synergistic inhibitory effects on prostate cancer cell viability and invasion. In vivo, ZD55-IL-24 and DTX synergistically inhibited the growth and activated the apoptosis of DU145 xenografts, accompanied by significantly decreased PARP-1 levels and increased caspase-3 and caspase-8 levels as well as decreased CD31 expression.

CONCLUSION

We reported the synergistic anti-tumor efficacy of ZD55-IL-24 and DTX on prostate cancer. Our results suggest that chemotherapy combined with oncolytic adenovirus mediated gene therapy is a promising strategy for the treatment of advanced prostate cancer.

One-year Outcomes in Patients with ST-segment Elevation Myocardial Infarction Caused by Unprotected Left Main Coronary Artery Occlusion Treated by Primary Percutaneous Coronary Intervention

Background

Very few data have been reported for ST-segment elevation myocardial infarction (STEMI) caused by unprotected left main coronary artery (ULMCA) occlusion, and very little is known about the results of this subgroup of patients who underwent primary percutaneous coronary intervention (PCI). The aim of this study was to determine the clinical features and outcomes of patients with STEMI who underwent primary PCI for acute ULMCA occlusion.

Methods

From January 2000 to February 2014, 372 patients with STEMI caused by ULMCA acute occlusion (ULMCA-STEMI) who underwent primary PCI at one of two centers were enrolled. The 230 patients with non-ST-segment elevation MI (NSTEMI) caused by ULMCA lesion (ULMCA-NSTEMI) who underwent emergency PCI were designated the control group. The main indexes were the major adverse cardiac events (MACEs) in-hospital, at 1 month, and at 1 year.

Results

Compared to the NSTEMI patients, the patients with STEMI had significantly higher rates of Killip class≥III (21.2% vs. 3.5%, χ² = 36.253, P < 0.001) and cardiac arrest (8.3% vs. 3.5%, χ² = 5.529, P = 0.019). For both groups, the proportions of one-year cardiac death in the patients with a post-procedure thrombolysis in myocardial infarction (TIMI) flow grade<3 were significantly higher than those in the patients with a TIMI flow grade of 3 (STEMI group: 51.7% [15/29] vs. 4.1% [14/343], P < 0.001; NSTEMI group: 33.3% [3/9] vs. 13.6% [3/221], P = 0.001; respectively]. Landmark analysis showed that the patients in STEMI group were associated with higher risks of MACE (16.7% vs. 9.1%, P = 0.009) and cardiac death (5.4% vs. 1.3%, P = 0.011) compared with NSTEMI patients at 1 month. Meanwhile, in patients with ULMCA, the landmark analysis for incidences of MACE and cardiac death was similar between the STEMI and NSTEMI (all P = 0.72) in the intervals of 1-12 months. However, patients who were diagnosed with STEMI or NSTEMI had no significant difference in reinfarction (all P > 0.05) and TVR (all P > 0.05) in the intervals of 0-1 month as well as 1 month to 1 year. The results of Cox regression analysis showed that the differences in the independent predictors for MACE included the variables of Killip class ≥ III and intra-aortic balloon pump support for the STEMI patients and the variables of previous MI, ULMCA distal bifurcation, and 2-stent for distal ULMCA lesions for the NSTEMI patients.

Conclusions

Compared to the NSTEMI patients, the patients with STEMI and ULMCA lesions still remain at a much higher risk for adverse events at 1 year, especially on 1 month. If a successful PCI procedure is performed, the 1-year outcomes in those patients might improve.

Combined antibacterial and osteogenic in situ effects of a bifunctional titanium alloy with nanoscale hydroxyapatite coating

To resolve the problems of bacterial infections and the low efficiency of osteogenesis of implanted titanium alloys in clinical dental and bone therapy, we developed a bifunctional titanium alloy (Ti) with a nano-hydroxyapatite (HA) coating (HBD + BMP/HA-Ti), which enables the sustained release of the natural antimicrobial peptide human β-defensin 3 (HBD-3) and bone morphogenetic protein-2 (BMP-2). Due to the poriferous nano-sized structure of the HA coating with a 20-30 μm thickness, the HBD + BMP/HA-Ti material had a high encapsulation efficiency (>74%) and exhibited synchronized slow release of HBD-3 and BMP-2. In an antibacterial test, HBD + BMP/HA-Ti prevented the growth of bacteria in an inoculated medium, and its surface remained free from viable bacteria after a continuous incubation with Gram-negative and Gram-positive strains for 7 days. Furthermore, good adhesion, proliferation and osteogenic differentiation of hBMSCs in contact with HBD + BMP/HA-Ti were achieved in 7 days. Therefore, the bifunctional titanium alloy HBD + BMP/HA-Ti has a great potential for eventual applications in the protection of implants against bacteria in the orthopaedic and dental clinic.

Functional polyurethane nanomicelle with pH-responsive drug delivery property

A new functional pH-responsive polyurethane-based nanomicelle has been developed with BES-Na as the functional monomer, the buffering agent with tertiary amine, and sulfonic acid group was incorporated into the hydrophilic shell as the functional agent, which resulted in polyurethane nanosystem with pH-sensitive property. Folic acid (FA) was chosen as model hydrophobic drug to evaluate the loading and pH-triggered release of the PU micelles in vitro drug loading and release. The drug loading content (LC) and the encapsulation efficiency (EE) for FA-loaded micelles in phosphate-buffered solutions were 7.68% and 27.72%, respectively, and the largest accumulative drug release percentages in pH 6.8 and pH 5.0 were 79.17% and 89.83% in 24 h, respectively. A facile and versatile approach has been provided for the design and fabrication of smart nanovehicles for effective drug delivery and opens a new thought in the design and fabrication of biodegradable polyurethanes for next generation of nanomicellar systems.

A Multicenter, Randomized, Double-Blind, and Placebo-Controlled Study of the Effects of Tongxinluo Capsules in Acute Coronary Syndrome Patients with High On-Treatment Platelet Reactivity

Background

High platelet reactivity (HPR) during clopidogrel treatment predicts postpercutaneous coronary intervention (PCI) ischemic events strongly and independently. Tongxinluo capsules (TCs) are a traditional Chinese medicine formulation used as antiplatelet treatment. However, its efficacy against HPR is not known. The aim of the present study was to evaluate the effects of TCs in acute coronary syndrome (ACS) patients with HPR.

Methods

This multicenter, randomized, double-blind, placebo-controlled study prospectively analyzed 136 ACS patients with HPR who underwent PCI. The patients were enrolled from November 2013 to May 2014 and randomized to receive placebo or TCs in addition to standard dual antiplatelet therapy (DAPT) with aspirin and clopidogrel. The primary end points were the prevalence of HPR at 30 days and the mean change in P2Y₁₂reaction units (PRUs) between baseline and 30 days. Survival curves were constructed with Kaplan-Meier estimates and compared by log-rank tests between the two groups.

Results

Both groups had a significantly reduced prevalence of HPR at 30 days versus baseline, but the TC group, compared with the placebo group, had greater reduction (15.8% vs. 24.8%, P = 0.013), especially among patients with one cytochrome P450 2C19 loss of function (LOF) allele (χ² = 2.931, P = 0.047). The TC group also had a lower prevalence of HPR (33.3% vs. 54.2%, t = 5.284, P = 0.022) and superior performance in light transmittance aggregometry and higher levels of high-sensitivity C-reactive protein (hsCRP), but the composite prevalence of ischemic events did not differ significantly (χ² = 1.587, P = 0.208).

Conclusions

In addition to standard DAPT with aspirin and clopidogrel, TCs further reduce PRU and hsCRP levels, especially in patients carrying only one LOF allele. The data suggest that TCs could be used in combination therapy for ACS patients with HPR undergoing PCI.

[Clinical analysis of one infantile nephrotic syndrome caused by COQ2 gene mutation and literature review]

Objective: To explore the clinical and genetic characteristics of infantile nephrotic syndrome caused by COQ2 variants. Methods: The clinical and genetic data of a patient with nephrotic syndrome caused by COQ2 variants diagnosed at pediatric department of Peking University First Hospital from February 2018 to March 2018 were retrospectively analyzed. Related literature retrieved from PubMed, CNKI and Wanfang databases were searched to date (up to July 2018) with "COQ2 gene" or "primary coenzyme Q10 deficiency" and "nephrotic syndrome" or "nephropathy" as key words. Results: A 14-month-old male, presented to local hospital at 11 months of age with edema and severe proteinuria, without hematuria, hypertension or renal dysfunction. He did not have infection or seizure in the course of the disease. He had no response to a more than four-week full-dose prednisone treatment. He had normal birth, mild motor development retardation and moderate language retardation. He was born to non-consanguineous healthy parents. He had two unaffected older sisters and one older sister died of "nephropathy" at one year of age. Genetic testing identified compound heterozygous variants in COQ2 gene: c.518G>A and c.973A>G, both could be predicted by in silico tools to be deleterious in protein function. These variants are not single nucleotide polymorphism and rare in normal populations. Both variants have previously been reported as pathogenic. These missense mutations were inherited from parents in autosomal recessive manner tested by Sanger sequencing. The patient was supplemented with high-dose of coenzyme Q10, at 30 mg/(kg·day) and glucocorticoid was withdrawn. Within three weeks of high dose coenzyme Q10 treatment, the edema disappeared. After seven weeks of high dose coenzyme Q10 treatment, the patient had decreased proteinuria and improved serum albumin levels. The urine protein to creatinine ratio decreased from 22.87 mg/mg to 1.98 mg/mg; Serum albumin increased from 14.2 g/L to 39.9 g/L, with normal kidney function and improved motor development. Primary CoQ10 deficiency is reported to be a rare autosomal recessive mitochondrial disorder with heterogeneous renal, neurologic, and muscular manifestations. To date, COQ2 variants have been reported in 14 children with glomerular involvement. Their age at onset ranged from neonatal period to 10-year-old (8 patients within the first year of life). Steroid resistant nephrotic syndrome (SRNS) is the most common phenotype. Some of these children also had progressing encephalopathy and myopathy, and seizures. Patients with COQ2 variants might show clinical improvement with early high-dose oral CoQ10 supplementation. Literature review revealed two Chinese articles, mainly about adults with neurologic symptoms. SRNS was previously not reported in Chinese pediatric patients. Conclusions: It is necessary to carry out genetic testing for infant with SRNS. The coexistence of some degree of encephalomyopathy, such as development retardation, should raise suspicion of a mitochondrial defect caused by COQ2 variants. Timely diagnostic genetic testing and early high dose of coenzyme Q10 supplement could significantly improve their prognosis.

Speciation analysis and leaching behaviors of selected trace elements in spent SCR catalyst

This study investigated heavy metal chemical speciation and leaching behavior from a board-type spent selective catalytic reduction (SCR) catalyst containing high concentrations of vanadium, chromium, nickel, copper, zinc, and lead. A three-step sequential extraction method, standard toxicity characteristic leaching procedure (TCLP), and leaching characteristic tests have been performed. It was found that the mobility of six heavy metals in the spent SCR catalyst was significantly different. The mobility of the six heavy metals exhibited the following order: Ni > Zn > V > Cr > As > Cu. Meanwhile, TCLP test results revealed relatively high Zn and Cr leaching rate of 83.20% and 10.35%, respectively. It was found that leaching rate was positively correlated with available contents (sum of acid soluble, reducible and oxidizable fractions). Leaching characteristics tests indicated that pH substantially affected the leaching of these heavy metals. In particular, the leaching of Cr, Ni, Cu, and Zn was positively influenced by strong acid, while V and As were easily released in the presence of strong acid and strong alkali (pH < 3 or pH > 11). In terms of kinetics, the leaching of Cr, Ni, Cu, Zn, and As within the spent catalyst was dominated by erosion and dissolution processes, which were rapid reaction processes. V was released in large amounts within 1 h, but its leaching amount sharply decreased with time due to readsorption.

[Value of Monochromatic Imaging on Spectral Detector CT in Metal Artifact Reduction of Denture Implants]

Objective To evaluate the role of monochromatic imaging in reducing metal artifacts and improving image quality in patients with denture implants undergoing head/neck plain CT. Methods Forty patients with denture implants undergoing head/neck plain CT on a dual-layer spectral detector CT were enrolled. The conventional and monochromatic 110 keV images were reconstructed from the same acquisition. The regions of interests (ROIs) were placed on the artifact streak (CT1),the soft tissue affected by the artifact (CT2),and the unaffected tissue (CT3). The artifact index (AI) and standard deviation (SD) were calculated. The image quality was compared.Results The attenuation of CT1 was significantly improved on monochromatic images than on conventional images [-195.00 (-700.40,44.80) vs. -336.50 (-1024.00,-77.00),P=0.00]. The attenuation of CT2 was significant different between monochromatic and conventional images [46.10 (-0.20,91.60) vs. 102.80 (4.60,210.20),P=0.00]. The difference between CT2 and CT3 was significantly smaller on monochromatic images than on conventional images [14.55 (0.00,44.00) vs. 51.30 (0.30,168.30),P=0.00]. The SD of CT2 was significantly smaller on monochromatic images than on conventional images [14.75 (7.80,35.00) vs. 23.25 (7.60,56.00),P=0.00]. The AI was significantly improved by monochromatic imaging [12.76 (3.53,34.14) vs. 19.00 (2.43,54.32),P=0.00]. Conclusion The monochromatic imaging can effectively reduce the artifacts caused by denture implants and improve image quality on head/neck plain CT.

Observation of Dicke cooperativity in magnetic interactions

The interaction ofNtwo-level atoms with a single-mode light field is an extensively studied many-body problem in quantum optics, first analyzed by Dicke in the context of superradiance. A characteristic of such systems is the cooperative enhancement of the coupling strength by a factor of N. In this study, we extended this cooperatively enhanced coupling to a solid-state system, demonstrating that it also occurs in a magnetic solid in the form of matter-matter interaction. Specifically, the exchange interaction ofNparamagnetic erbium(III) (Er3+) spins with an iron(III) (Fe3+) magnon field in erbium orthoferrite (ErFeO3) exhibits a vacuum Rabi splitting whose magnitude is proportional to N. Our results provide a route for understanding, controlling, and predicting novel phases of condensed matter using concepts and tools available in quantum optics.

Real-Time Monitoring of Bond Slip between GFRP Bar and Concrete Structure Using Piezoceramic Transducer-Enabled Active Sensing

Glass fiber-reinforced polymers (GFRPs) have received increasing attention in recent years due to their overall performance of light weight, low cost and corrosion resistance, and they are increasingly used as reinforcement in concrete structures. However, GFRP material has low elastic modulus and linear elastic properties compared with steel bars, which introduces different bonding characteristics between bars and concrete. Therefore, a reliable monitoring method is urgently needed to detect the bond slip in GFRP-reinforced concrete structures. In this paper, a piezoceramic-based active sensing approach is proposed and developed to find the debonding between a GFRP bar and the concrete structure. In the proposed method, we utilize PZT (lead zirconate titanate) as two transducers. One acts as an actuator which is buried in the concrete structure, and the other acts as a sensor which is attached to the GFRP bar by taking advantage of machinability of the GRRP material. Both transducers are strategically placed to face each other across from the interface between the GFRP bar and the concrete. The actuator provokes a stress wave that travels through the interface. Meanwhile, the PZT patch that is attached to the GFRP bar is used to detect the propagating stress wave. The bonding condition determines how difficult it is for the stress wave traveling through the interface. The occurrence of a bond slip leads to cracks between the bar and the concrete, which dramatically reduces the energy carried by the stress wave through the interface. In this research, two specimens equipped with the PZT transducers are fabricated, and pull-out tests are conducted. To analyze the active sensing data, we use wavelet packet analysis to compute the energy transferred to the sensing PZT patch throughout the process of debonding. Experimental results illustrate that the proposed method can accurately capture the bond slip between the GFRP bar and the concrete.

[Identification of compound heterozygous mutations p.Gly400Val and p.Arg532Ter of the F11 gene in a Chinese patient with hereditary factor XI deficiency]

OBJECTIVE

To investigate the phenotype and genotype defect characteristics of a Chinese patient with hereditary factor XI deficiency.

METHODS

The activated partial thromboplastin time (APTT), prothrombin time (PT), FXI activity (FXI:C) of the proband and his relatives were measured by a clotting method using automatic coagulation analyzer. FXI antigen (FXI:Ag) was assayed by enzyme-linked immunosorbent assay (ELISA). Fifteen exons of the F11 gene were amplified by PCR and sequenced. Pymol software was used to analyze the novel mutations.

RESULTS

The APTT of the proband was significantly prolonged (70.3 s, reference 34.5 s) with decreased FXI activity (6%, reference 50%-150%) and FXI antigen (1.9%, reference 50%-150%). The FXI activity and FXI antigen of his son was 31% and 39%, respectively. Two heterozygous F11 mutations were identified in the proband, which included a G to T substitution at nucleotide 1296 in exon 11 resulting in substitution of glycine by valine at codon 400 (p.Gly400Val) and a A to T substitution at nucleotide 1691 in exon 14 resulting in substitution of arginine (AGA) by a termination codon (TGA) at codon 532 (p.Arg532Ter). Analysis using Pymol indicated that the number of hydrogen bonds has changed, which led to a transformation of the structure of the FXI protein. The son of the proband was found to be heterozygous for the c.1296G to T (p.Gly400Val) mutation. NM_13142 c.1691A to T (p.Arg532Ter) is a novel mutation based on HGMD professional 2016.4. Based on 2015 Guidelines of ACMG, it is PVS1 (very strong pathogenicity).

CONCLUSION

The compound heterozygous mutations of F11 NM_13142 c.1296G to T (p.Gly400Val) and F11 NM_13142 c.1691A to T(p.Arg532Ter) probably underlies the FXI deficiency in the proband.

T1-T2 molecular magnetic resonance imaging of renal carcinoma cells based on nano-contrast agents

BACKGROUND

The development of T₁-T₂ dual contrast agent (CA) favors the visualization of the lesion in a more accurate and reliable manner by magnetic resonance imaging (MRI). The relaxivity and the interference between T₁ and T₂ CA are the main concerns for their design.

METHODS

In this work, we constructed an Fe₃O₄@mSiO₂/PDDA/BSA-Gd₂O₃ nanocomplex where BSA-Gd₂O₃ NPs and Fe₃O₄ NPs were chosen as T₁ and T₂ MRI CAs and a 20 nm mesoporous silica (mSiO₂) nanoshell was introduced to reduce the interference between them. We performed transmis sion electron microscopy, X-ray powder diffraction, UV-vis absorption spectra, and Fourier transform infrared absorption (FTIR) spectra to characterize the prepared nanocom-plex and MRI scanning to evaluate their MRI behaviors. Furthermore, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and hematologic and biochemical analyses were introduced to evaluate their in vitro and in vivo toxicity. Finally, the specific MRI of 786-0 cells with Fe₃O₄@mSiO₂/PDDA/BSA-Gd₂O₃-AS1411 nanoprobe in vitro was realized. In vivo biodistribution of Fe₃O₄@mSiO₂/PDDA/BSA-Gd₂O₃ nanocomplex in the mouse was determined by the quantification of the Gd element by inductively coupled plasma-mass spectrometry.

RESULTS

The prepared Fe₃O₄@mSiO₂/PDDA/BSA-Gd₂O₃ nanocomplex possessed high longitudinal (r₁=11.47 mM s^-1 Gd) and transverse (r₂=195.1 mM s^-1 Fe) relaxivities, enabling its use as a T₁-T₂ dual contrast agent for MRI. MTT testing and hematologic and biochemical analysis indicated the good biocompatibility of Fe₃O₄@mSiO₂/PDDA/BSA-Gd₂O₃ nanocomplex in vitro and in vivo. After further conjugation with AS1411 aptamer, they could target tumor cells successfully by T₁ and T₂ MRI in vitro. The possible metabolic pathway of the tail vein-injected Fe₃O₄@mSiO₂/PDDA/BSA-Gd₂O₃ nanocomplex in mouse was mainly via kidney.

CONCLUSION

A T₁-T₂ dual-mode contrast agent, Fe₃O₄@mSiO₂/PDDA/BSA-Gd₂O₃ nano-complex, was developed and its good performance for tumor cell targeting in vitro and kidney contrast-enhanced MRI in mice indicated its promising potential as an effective T₁-T₂ dual-mode contrast agent for in vivo MRI with self-confirmation.

Abstract 512: Regulation of Neutrophil Extracellular Traps (NETs) by Mesenchymal Stromal Cell Derived Adenosine

Introduction: Mesenchymal stromal cells (MSCs) reduce the infiltration of leukocytes into the heart after ischemia reperfusion injury (MI/R). Inhibition of the surface ectonucleotidase CD73 prevents this anti-inflammatory effect. CD73 is a key step in a pathway that converts adenine nucleotides (ATP, ADP, AMP) into adenosine, which in turn exerts vasodilatory and immunosuppressive effects. Neutrophil extracellular trap (NET) formation is a thrombotic and inflammatory process involved in coronary occlusion and myocardial damage. We hypothesized that adenosine may be a key regulator of NET formation and that CD73-dependant adenosine production by MSCs reduces NETs after MI/R.

Methods: Neutrophils isolated from venous blood of healthy donors by percoll gradient density centrifugation were cultured with MSCs for in vitro studies. MSCs were encapsulated in aliginate by electrostatic encapsulation and secured to the epicardium with PEG-maleimide hydrogel at the time of reperfusion. This biomaterial strategy supports and maintains viable cells in the vicinity of injury for 1 week. 24 hours after injury, hearts were perfused, excised, and digested and NETs quantified by flow cytometry.

Results: Treatment of neutrophils with adenosine or the adenosine receptor agonist NECA reduces NET formation in vitro . Co-culture of MSCs with neutrophils also prevents NET formation. Inhibition of CD73 activity on MSCs with the antagonist APCP prevents the anti-NET activities of MSCs. In vivo , encapsulation and placement of MSCs on the epicardial surface at the time of MI/R reduces myocardial NETs 24 hours after MI/R. Treatment of MSCs with APCP prior to implantation reduces the anti-NET effects of MSCs, as well as functional benefits.

Conclusions: There is growing evidence of the importance of NETs in cardiac ischemia-reperfusion injury but little is known of the regulation of NETs in vivo . Our data suggests that adenosine exerts a strong anti-NET effect and that CD73-generated adenosine from MSCs may be capable of in vivo anti-inflammatory and anti-NET regulation. Future studies are focused on genetic techniques to knock down CD73 activity on MSCs, direct implication of NETs on cardiovascular pathophysiology, and non-cellular methods to deliver CD73 in MI/R.

Abstract 251: The Role of Adenosine Derived From Mesenchymal Stromal Cell on Neutrophil Extracellular Trap Formation in Myocardial Ischemia Reperfusion

Introduction: In response to tissue damage or infection, neutrophils expel their chromatin into the extracellular space in a thrombotic and inflammatory process called neutrophil extracellular traps(NETs). There is increasing evidence that NETs play a role in myocardial ischemia/reperfusion (MI/R) injury. NETs are found in thrombi aspirated from coronary arteries, atherosclerotic plaques, and deep vein thrombosis. However, nothing is known about the regulation of NETs in vivo. We hypothesized that adenosine, well know for anti-inflammatory effects, reduces NET formation. After MI/R, adenosine is made from conversion of ATP released from damaged cells.

Methods: Neutrophils were isolated from human venous blood and stimulated to produce NETs by PMA, a PKC agonist and is well known to induce robust NET formation and serves as a positive control. NETs were quantified by Sytox green fluorescent to quantify extracellular DNA and immunohistochemical staining for citrullinated histone H3, a specific marker of NETs.

Results: Neutrophils treated with PMA increased NET production (1.81fold vs unstimulate groups, p<0.001, n=27-28). Neutrophils treated with adenosine (10uM) had a 30.2% decrease NET formation (p<0.001, n=15). There are four adenosine receptors called A1, A2a, A2b, and A3. We used agonists and antagonists’ strategy to check probable receptors involved in suppression NETs signal. We find both A2a receptor agonist-CGS 21680 and A2b agonist-BAY 60-6583 can suppress NETs formation (29.6% and 29.3% respectively p<0.001, n=5-6). But only A2a antagonist-ZM241385 can reverse adenosine’s inhibition (13.8%v.s.24.7%, p<0.05, n=6).

Conclusion: Adenosine can downregulate NET formation in vitro likely through A2a receptor activation. Future studies will investigate A2a receptor using genetic knock out, as well as in vivo significance of NET inhibition in MI/R.

Tectorigenin inhibits RANKL-induced osteoclastogenesis via suppression of NF-κB signalling and decreases bone loss in ovariectomized C57BL/6

Metabolism of bone is regulated by the balance between osteoblast‐mediated bone formation and osteoclast‐mediated bone resorption. Activation of osteoclasts could lead to osteoporosis. Thus, inhibiting the activity of osteoclasts becomes an available strategy for the treatment of osteoporosis. Tectorigenin is an extract of Belamcanda chinensis In the present study, the anti‐osteoclastogenesis effects of tectorigenin were investigated in vitro and in vivo. The results showed preventive and therapeutic effects of tectorigenin at concentrations of 0, 10, 40, and 80 μmol/L in the maturation and activation of osteoclasts. A signalling study also indicated that tectorigenin treatment reduces activation of NF‐κB signalling in osteoclastogenesis. Animal experiment demonstrated that tectorigenin treatment (1‐10 mg/kg, abdominal injection every 3 days) significantly inhibits bone loss in ovariectomized C57BL/6. Our data suggest that tectorigenin is a potential pharmacological choice for osteoporosis.