Electrochemical immunosensor for highly sensitive detection of cTnI via in-situ initiated ROP signal amplification strategy.

Cardiac troponin I (cTnI) is considered to be the most valuable biomarker for the diagnosis of acute myocardial infarction (AMI). The sensitive and efficient determination of cTnI is essential for the early diagnosis and prognostic assessment of AMI. In this paper, we designed for the first time an electrochemical immunosensor based on the ring-opening polymerization (ROP) reaction as a signal amplification strategy for the highly sensitive detection of cTnI. Briefly, 3-mercaptopropionic acid (MPA) was used as a cross-linking agent to immobilize Ab1 on the surface of gold electrodes, and subsequently Ab1 specifically captured cTnI. Then, the glycolic acid-coupled cTnI-secondary antibody (GA-Ab2) bound specifically to cTnI to form a sandwich structure and provided the initiation site for the subsequent polymerization reaction. Subsequently, ferrocene formyloxyate propylene oxide (FFAPO) was used as the monomer and large quantities of electroactive polymers were grafted to the electrode surface via a hydroxyl-initiated ROP reaction, which significantly amplified the electrochemical signal. Under optimal conditions, the immunosensor displayed good linearity in the concentration range of 1 pg mL-1-1 µg mL-1 and the limit of detection down to 57.14 fg mL-1, which was superior to most of those reported assays. Compared to other signal amplification strategies, this ROP reaction showed relatively easy access to raw materials and comparatively mild reaction conditions. In addition, the results of the serum sample detection capability indicated that the immunosensor exhibited excellent detection selectivity and reliability in serum. Thus, owing to its good selectivity, high sensitivity and excellent stability, the immunosensor shows great potential for clinical application.

Outcome of Extracorporeal Membrane Oxygenation Combined with Intraaortic Balloon Pump Hemodynamic Support during the Percutaneous Coronary Intervention Process for Patients with Cardiac Shock Complicating Acute Myocardial Infarction.

We evaluate the effect of extracorporeal membrane oxygenation combined with intraaortic balloon pump mechanical circulatory support for patients with cardiogenic shock complicating acute myocardial infarction during the PCI process. Extracorporeal membrane oxygenation combined with intraaortic balloon pump hemodynamic support during the percutaneous coronary intervention process for patients with cardiac shock complicating acute myocardial infarction might play a complementary role. Yet, evidence of application of both devices at the same time remains unclear. Patients with cardiogenic shock complicating myocardial infarction who underwent PCI in our hospital from January 2015 to January 2018 were screened. Those who were under hemodynamic support of extracorporeal membrane oxygenation combined with intraaortic balloon pump were enrolled as the ECMO&IABP group, and the patients only under support of intraaortic balloon pump were enrolled as the IABP group. The differences of clinical prognosis between the two groups were compared. A total of 39 patients were enrolled into the study: 10 were in the ECMO&IABP group and 29 in the IABP group. Compared with the IABP group, more patients were complicated with old myocardial infarction (5/10 vs. 2/29, p=0.002), more patients were diagnosed as non-ST elevated myocardial infarction (8/10 vs. 11/29, p=0.002) and left ventricular ejecting fraction was lower (41.1 ± 9.86 vs. 48.55 ± 8.86, p=0.03) in the ECMO&IABP group. Mechanical complications were higher in the ECMO&IABP group (5/10 vs. 5/29, p=0.048), The survive rate in the ECMO&IABP group is higher than that in the IABP group (90.00% vs. 47.83%, p=0.042) at one-year follow-up. Compared with only IABP, ECMO combined with IABP hemodynamic support during the PCI process for patients with cardiogenic shock complicating acute myocardial infarction enjoys better mortality outcome.

A space-sacrificed pyrolysis strategy for boron-doped carbon spheres with high supercapacitor performance.

Targeting the potential application of morphological carbon in electrode materials, a space-sacrificed pyrolysis strategy was applied for the preparation of boron-doped carbon spheres (B-CSs), using commercial triphenyl borate (TPB) as carbon and boron co-source. The unique structure of TPB play an important role in the sacrificed space, and has notable effect on the surface area of B-CSs. The as prepared B-CSs possess a high surface area and boron content with uniform boron atoms distribution and high surface polarity, which contributes to the improvement of pseudo-capacitance. The sizes, specific surface areas, and boron contents of B-CSs can be easily regulated by varying the experimental parameters. The optimal sample has a boron content of 1.38 at%, surface area of 560 m2 g-1 and specific capacitance of 235F g-1. We can believe that this work would provide a flexible and extensible preparation technique of B-CSs for electrochemical applications.

Danlou Tablet Activates Autophagy of Vascular Adventitial Fibroblasts Through PI3K/Akt/mTOR to Protect Cells From Damage Caused by Atherosclerosis.

Danlou tablet (DLT), a commercial Chinese patent medicine, has been widely used to treat cardiovascular diseases for many years. Atherosclerosis (AS) is the leading cause of cardiovascular disease. Increasing evidence indicates that autophagy plays a vital role in the development of AS. Here we investigated whether DLT could activate autophagy to improve AS and further clarified its underlying mechanisms. In an ApoE-/- mice model, the results of Oil red O, Masson's trichrome, and H&E staining techniques showed that DLT significantly inhibited lipid accumulation and fibrosis formation in atherosclerotic plaque tissue. DLT also inhibited serum triglyceride, cholesterol, and low-density lipoprotein levels and suppressed serum levels of inflammatory factors interleukin-6 and tumor necrosis factor-α in ApoE-/- mice. Moreover, DLT suppressed proliferation, migration, and invasion of human vascular adventitial fibroblasts (HVAFs) by inhibiting the PI3K/Akt/mTOR pathway. In addition, western blot analysis showed that Danlou tablet treatment decreased the expression of p62 and increased Beclin 1 and LC3 I -to-LC3 II ratios in HVAFs. The role of autophagy in treating atherosclerosis by DLT is confirmed by 3-methyladenine (autophagy inhibitor) and rapamycin (autophagy activator) in HVAFs. In summary, DLT activated PI3K/Akt/mTOR-mediated autophagy of vascular adventitial fibroblasts to protect cells from damage caused by atherosclerosis.

Dopamine D4 receptor protected against hyperglycemia-induced endothelial dysfunction via PI3K /eNOS pathway.

Hyperglycemia-induced endothelial dysfunction is generally believed to be the basis of diabetic vascular complications. Dopamine receptors is known to play an important protective role in diabetes. However, the protective effect of dopamine receptors against hyperglycemia-induced endothelial damage in diabetic rats is still unknown. In the present study, we established a cell model of hyperglycemia-induced endothelial dysfunction by treating human umbilical vein endothelial cells (HUVEC) with high glucose. MTT and lactate dehydrogenase assays results showed that high glucose treatment significantly reduced the cell viability and down-regulated dopamine D4 receptor. Pre-treatment with PD168077, a specific D4 receptor agonist, greatly improved endothelial cell viability and decreased apoptosis. Furthermore, pharmacological inhibition of phosphoinositide 3-kinase (PI3K) and endothelial nitric oxide synthase (eNOS) eliminated the protective effect of D4 receptor against endothelial injury. More importantly, the expression level of D4 receptor was also dramatically down-regulated in the arterial endothelium of rats with streptozotocin-(STZ)-induced diabetes, and the STZ-induced impairment of acetylcholine-induced vasodilation was reversed by activation of D4 receptor. In conclusion, our results indicated that dopamine D4 receptor protected against hyperglycemia-induced endothelial dysfunction via the PI3K/eNOS pathway, which may provide a novel strategy in the treatment of diabetes.

Electrochemical cholesterol sensor based on carbon nanotube@molecularly imprinted polymer modified ceramic carbon electrode.

A monolithic molecular imprinting sensor based on ceramic carbon electrode (CCE) has been reported. The sensor can be renewed simply by smoothing. It was fabricated by thoroughly mixing multiwalled carbon nanotube@molecularly imprinted polymer (MWCNT@MIP), graphite powder, and silicon alkoxide, and then packing the resulting complex mixture of components firmly into the electrode cavity of a Teflon sleeve. The incorporated MWCNT@MIP in CCEs functioned as a recognition element for cholesterol determination. The MWCNT@MIP-CCEs were tested in the presence or absence of cholesterol by cyclic voltammetry and linear sweep voltammetry. The cholesterol sensor has excellent sensitivity with a linear range of 10-300nM and a detection limit of 1nM (S/N=3). The monolithic molecular imprinting sensor exhibits good stability, high sensitivity, and user-friendly reusability for cholesterol determination. This study shows that CCE is a promising matrix for MIP sensors.

An amperometric sensor for the determination of benzophenone in food packaging materials based on the electropolymerized molecularly imprinted poly-o-phenylenediamine film.

Benzophenone is one of the most commonly used photoinitiators of UV-cured inks on food packaging materials and can migrate into foodstuffs. In this study, an amperometric benzophenone sensor based on molecularly imprinted polymer (MIP) was successfully constructed for the first time. The sensor was prepared by electropolymerizing o-phenylenediamine (o-PD) on a glassy carbon electrode (GCE) in the presence of template benzophenone, and then removing the template by immersing the poly-o-phenylenediamine film-modified GCE in ethanol. The molecularly imprinted sensor was tested in the presence or absence of benzophenone by cyclic voltammetry and linear sweep voltammetry to verify the changes in the redox peak currents of potassium ferricyanide. The sensor responded sensitively to benzophenone over a linear range of 0.05-5 µM with a detection limit of 10 nM. The imprinted sensor showed high recognition ability for benzophenone and was successfully applied to the determination of benzophenone in food packaging material samples.

Syntheses of chitin-based imprinting polymers and their binding properties for cholesterol.

A novel chitin derivative, cholesteryl chitin carbonate (Chitin-Chol), was synthesized from chitin and cholesteryl chloroformate. This product was characterized by Fourier transform infrared (FTIR) spectroscopy and solid-state ¹³C nuclear magnetic resonance (¹³C NMR), and was used as a covalently bound template precursor for imprinting cholesterol. After cross-linking with toluene 2,4-diisocyanate, it was efficiently cleaved hydrolytically to afford a guest-binding site accompanying the easy and efficient removal of a sacrificial spacer. The selectivity and efficacy of a chitin-based imprinting polymer for steroid binding were assessed by a chromatographic screening process. The results of binding experiments showed that this molecular imprinting polymer (MIP) has a high binding capacity with cholesterol. The target discrimination towards cholesterol over its close structural analogue suggested that the polymer recognition site was possible on the basis of the inversion of configuration of a single hydroxyl group. In addition, non-covalent imprinting was done using chitin as a precursor and its binding properties for cholesterol were also evaluated.

Gene transfer into porcine myocardium via pericardial cavity by homemade easy puncture device.

OBJECTIVE: To explore the feasibility and safety of gene transfer into porcine myocardium via the pericardial cavity by a homemade easy device. METHODS: Replication-deficient recombinant adenoviral vector carrying LacZ report gene (Ad-LacZ) was constructed by the calcium phosphate precipitation method. Twelve healthy Chinese mini-swine were randomly divided into experimental group (n = 6) and control group (n = 6). Acute myocardial infarction (AMI) model was established by balloon occlusion of the distal part of D1 branch of left anterior descending (LAD) artery, at the same time the intrapericardial cavity injections were performed through the small incision of the abdominal wall below the xyphoid appendix using a homemade device. Then gene transfer was performed using a central venous catheter. The pericardium was pretreated with injection of a mixture of collagenase (1,200 U) and hyaluronidase (3,000 U) in both groups. Then 2.0 x 10(9) plaque formation unit (PFU) Ad-LacZ was injected into the pericardial cavity in experimental group, while 1 mL of normal saline was injected in the control group. The beta-galactosidase activity detection and X-gal staining of the ischemic myocardium were performed on the 3rd, 7th, and 28th day after injection. RESULTS: The LAD artery was occluded completely and infarction and ischemia were detected by histological assessment In experimental group, the X-gal staining positive cells and beta-galactosidase activity quantification were detectable on the 3rd day after injection, increased markedly on the 7th day, and then declined on the 28th day. The transfer efficiencies indicated by the positive myocardial cells were 16.7%, 45.6% , 22.8% on the 3rd, 7th, 28th day, respectively. In control group, no positive cells and beta-galactosidase activity were observed. CONCLUSION: Adenovirus can be transferred into ischemic myocardium and express target gene in the AMI model for four weeks with the homemade easy device via pericardial cavity pretreated by collagenase and hyaluronidase.