A self-assembled DNA double-crossover-based fluorescent aptasensor for highly sensitivity and selectivity in the simultaneous detection of aflatoxin M1 and aflatoxin B1.

Realizing the simultaneous speedy detection of multiple mycotoxins in contaminated food and feed is of great practical importance in the domain of food manufacturing and security. Herein, a fluorescent aptamer sensor based on self-assembled DNA double-crossover was developed and used for effective simultaneous quantitative detection of aflatoxins M1 and B1 by fluorescence resonance energy transfer (FRET). Fluorescent dye-modified aflatoxin M1 and B1 aptamers are selected as recognition elements and signal probes, and DNA double crosses are consistently locked by the aflatoxin aptamers, which results in a "turn-off" of the fluorescent signal. In the presence of AFM1 and AFB1, the aptamer sequences are more inclined to form Apt-AFM1 and Apt-AFB1 complexes, and the fluorescent probes are released from the DNA double-crossing platform, leading to an enhanced fluorescent signal (Cy3: 568 nm; Cy5: 660 nm). Under the optimal conditions, the signal response of the constructed fluorescent aptamer sensor showed good linearity with the logarithm of AFM1 and AFB1 concentrations, with detection limits of 6.24 pg/mL and 9.0 pg/mL, and a wide linear range of 0.01-200 ng/mL and 0.01-150 ng/mL, respectively. In addition, the effect of potential interfering substances in real samples was analyzed, and the aptasensor presented a good interference immunity. Moreover, by modifying and designing aptamer probes, the sensor can be applied to high-throughput simultaneous screening of other analytes, providing a new approach for the development of fluorescent aptamer sensors.

Dose-dependent pharmacokinetics of midazolam in rats: influence of hepatic first-pass metabolism.

To characterise the dose-dependent pharmacokinetics of midazolam and evaluate the intestinal and hepatic first-pass effects on midazolam in Sprague-Dawley rats, the concentrations and area under the concentration-time curve (AUC) of midazolam in the portal and systemic plasma were simultaneously determined with a double cannulation method.It was found that about 75% of the dose was left in the portal blood with different oral administration doses, while the bioavailability in the liver was 37.86% at 20 mg/kg, significantly higher than 9.16% at 2 mg/kg.The disproportional increase in AUC of midazolam and significant decrease in exposure of metabolites were observed in systemic plasma after hepatic portal vein administration. And in the in vitro study, the formation rate of the metabolites of midazolam significantly decreased when midazolam was at 300 µM compared with 100 µM.These results indicated that not only the saturation of first-pass metabolism but also the inhibition of hepatic metabolism is responsible for the nonlinear PK of midazolam. Thus, a rational dose should be chosen when midazolam is used as a probe in the drug-drug interaction study, particularly for orally administered drugs that undergo hepatic first-pass metabolism.

Relationship between epicardial adipose tissue attenuation and coronary artery disease in type 2 diabetes mellitus patients.

BACKGROUND AND AIMS: High epicardial adipose tissue (EAT) attenuation is a key characteristic of adipose tissue dysfunction and associated with coronary artery disease (CAD). As little is known about the modulation of EAT attenuation by metabolic disorders, we investigated the association between EAT attenuation and CAD risk factors, CAD presence and CAD severity in type 2 diabetes mellitus (T2DM) patients. METHODS: We included 276 inpatients with T2DM and 305 control patients with normal glucose metabolism (NGM), who underwent cardiac computed tomography angiography (CCTA) and coronary artery calcium (CAC) scoring. EAT attenuation and volume were evaluated by contrast-enhanced CCTA image analysis. Furthermore, segment stenosis scores (SSSs) of the left main coronary artery (LMCA), left anterior descending artery (LAD), left circumflex artery (LCX), right coronary artery (RCA), diagonal/intermediate branch (D/I) and obtuse marginal branch (OM) were calculated to assess CAD severity. RESULTS: T2DM patients showed higher significant CAC scores, coronary plaque prevalence, total SSSs and LMCA-SSSs, LAD-SSSs, LCX-SSSs, RCA-SSSs and D/I-SSSs compared with NGM controls. In contrast to NGM controls, EAT volume was significantly increased in T2DM patients, whereas EAT attenuation was similar. In T2DM patients, EAT attenuation was associated with discrete CAD risk factors, the presence of coronary and triple-vessel plaques, as well as LAD-SSSs, LCX-SSSs, RCA-SSSs and total SSSs. In addition, EAT attenuation was only associated with the total SSS of calcified plaques, but not with noncalcified plaques. CONCLUSION: In T2DM patients, high EAT attenuation is associated with the presence and severity of CAD in general and with coronary stenosis caused by calcified plaques in particular.

Effect of Ginkgo biloba extract on pharmacology and pharmacokinetics of atorvastatin in rats with hyperlipidaemia.

Ginkgo biloba extract (GBE) is a common dietary supplement used by people with dyslipidaemia worldwide to reduce the risk of cardiovascular disease. Many studies have found that GBE itself has a variety of pharmacological activities. However, the role of GBE as an adjunct to conventional therapy with chemical drugs remains controversial. Therefore, this study explored the additional benefits of GBE in the treatment of hyperlipidaemia with statins in terms of both pharmacodynamics and pharmacokinetics. A hyperlipidaemia model was established by feeding rats a high-fat diet for a long time. The animals were treated with atorvastatin only, GBE only, or a combination of atorvastatin and GBE. The results showed that statins combined with GBE could significantly improve the blood lipid parameters, reduce the liver fat content, and reduce the size of adipocytes in abdominal fat. The effect was superior to statin therapy alone. In addition, the combination has shown additional liver protection against possible pathological liver injury or statin-induced liver injury. A lipidomic study showed that GBE could regulate the abnormal lipid metabolism of the liver in hyperlipemia. When statins are combined with GBE, this callback effect introduced by GBE on endogenous metabolism has important implications for resistance to disease progression and statin resistance. Finally, in the presence of GBE, there was a significant increase in plasma statin exposure. These results all confirmed that GBE has incremental benefits as a dietary supplement of statin therapy for dyslipidaemia.

Comprehensive Evaluation of Metabolism and the Contribution of the Hepatic First-Pass Effect in the Bioavailability of Glabridin in Rats.

Glabridin is a bioactive isoflavan, which has a wide range of biological properties and is widely used in the market of health products and dietary supplements. However, the transformation pathway of glabridin in vivo is unclear, and the bioavailability is controversial among different studies. Therefore, a new HPLC-Q-TOF method was developed to analyze and identify the prototype and metabolites of glabridin in rats. A total of 63 compounds were identified, including hydroxylation, demethylation, acetylation, demethylation to carboxylation, glucuronidation, and sulfate conjugation, and 43 of which were new metabolites that had not been reported. Additionally, our study verified that the oral bioavailability of glabridin was 6.63 ± 2.29% in rats. Furthermore, we found that the hepatic first-pass effect was 62.12 ± 15.7% for glabridin. These results indicated that a high hepatic first-pass effect and extensive metabolism of glabridin in vivo may lead to its limited oral bioavailability.

Impact of procedural variability and study design quality on the efficacy of cell-based therapies for heart failure - a meta-analysis.

BACKGROUND: Cell-based therapy has long been considered a promising strategy for the treatment of heart failure (HF). However, its effectiveness in the clinical setting is now doubted. Because previous meta-analyses provided conflicting results, we sought to review all available data focusing on cell type and trial design. METHODS AND FINDINGS: The electronic databases PubMed, Cochrane library, ClinicalTrials.gov, and EudraCT were searched for randomized controlled trials (RCTs) utilizing cell therapy for HF patients from January 1, 2000 to December 31, 2020. Forty-three RCTs with 2855 participants were identified. The quality of the reported study design was assessed by evaluating the risk-of-bias (ROB). Primary outcomes were defined as mortality rate and left ventricular ejection fraction (LVEF) change from baseline. Secondary outcomes included both heart function data and clinical symptoms/events. Between-study heterogeneity was assessed using the I2 index. Subgroup analysis was performed based on HF type, cell source, cell origin, cell type, cell processing, type of surgical intervention, cell delivery routes, cell dose, and follow-up duration. Only 10 of the 43 studies had a low ROB for all method- and outcome parameters. A higher ROB was associated with a greater increase in LVEF. Overall, there was no impact on mortality for up to 12 months follow-up, and a clinically irrelevant average LVEF increase by LVEF (2.4%, 95% CI = 0.75-4.05, p = 0.004). Freshly isolated, primary cells tended to produce better outcomes than cultured cell products, but there was no clear impact of the cell source tissue, bone marrow cell phenotype or cell chricdose (raw or normalized for CD34+ cells). A meaningful increase in LVEF was only observed when cell therapy was combined with myocardial revascularization. CONCLUSIONS: The published results suggest a small increase in LVEF following cell therapy for heart failure, but publication bias and methodologic shortcomings need to be taken into account. Given that cardiac cell therapy has now been pursued for 20 years without real progress, further efforts should not be made. STUDY REGISTRY NUMBER: This meta-analysis is registered at the international prospective register of systematic reviews, number CRD42019118872.

Comparative analysis of adeno-associated virus serotypes for gene transfer in organotypic heart slices.

BACKGROUND: Vectors derived from adeno-associated viruses (AAVs) are widely used for gene transfer both in vitro and in vivo and have gained increasing interest as shuttle systems to deliver therapeutic genes to the heart. However, there is little information on their tissue penetration and cytotoxicity, as well as the optimal AAV serotype for transferring genes to diseased hearts. Therefore, we aimed to establish an organotypic heart slice culture system for mouse left ventricular (LV) myocardium and use this platform to analyze gene transfer efficiency, cell tropism, and toxicity of different AAV serotypes. METHODS: LV tissue slices, 300 µm thick, were prepared from 15- to 17-day-old transgenic alpha-myosin heavy-chain-mCherry mice using a vibrating microtome. Tissue slice viability in air-liquid culture was evaluated by calcein-acetoxymethyl ester staining, mCherry fluorescence intensity, and the tetrazolium assay. Four recombinant AAV serotypes (1, 2, 6, 8) expressing green fluorescent protein (GFP) under the CAG promoter were added to the slice surface. Gene transfer efficiency was quantified as the number of GFP-positive cells per slice. AAV cell tropism was examined by comparing the number of GFP-positive cardiomyocytes (CMs) and fibroblasts within heart slices. RESULTS: Slices retained viability in in vitro culture for at least 5 days. After adding AAV particles, AAV6-infected slices showed the highest number of GFP-expressing cells, almost exclusively CMs. Slice incubation with AAV1, 2, and 8 resulted in fewer GFP-positive cells, with AAV2 having the lowest gene transfer efficiency. None of the AAV serotypes tested caused significant cytotoxicity when compared to non-infected control slices. CONCLUSIONS: We have established a readily available mouse organotypic heart slice culture model and provided evidence that AAV6 may be a promising gene therapy vector for heart failure and other cardiac diseases.

Right Ventricular Rupture in Redo Coronary Artery Bypass Grafting.

A 71-year-old man presented to us with recurrent chest pain, which led to cardiac catheterization. He was a strong candidate for redo coronary artery bypass grafting (CABG). CT was performed to confirm whether the heart was adherent to the sternum and chest wall. For safety reasons, cardiopulmonary bypass (CPB) was first performed via right femoral cannulation before sternotomy. After the spontaneous right ventricular (RV) rupture, HTK was used to arrest the heart. Heart repair materials were applied to repair the fissure of RV to avoid further tearing and bleeding. A compromise scheme was adopted when it was found to be difficult to identify and expose well the target artery, due to severe adhesion. This was done to avoid possible severe consequences of further dissection of the heart. Intraoperative transesophageal echocardiography (TEE) was used to evaluate the cardiac function, and intra-aortic balloon pump (IABP) support was applied in time. In consideration of the RV enlargement, which TEE revealed may have been caused by myocardial edema and cardiac insufficiency, modified ultrafiltration was performed, and a timely decision of open chest management (OCM) with delayed sternal closure (DSC) was made to maintain hemodynamic stability. The patient had no further complications and eventually recovered well, according to a 4-month follow up.

Precision Diagnosis and Treatment of a Giant Pseudoaneurysm of the Right Ventricular Outflow Tract.

Pseudoaneurysm (PSA) of the right ventricular outflow tract (RVOT) is an exceedingly rare adverse event after the surgical reconstruction of the RVOT for the treatment of congenital heart disease. We report an unusual giant PSA of RVOT in a 20-month-old child, who underwent correction of the tetralogy of Fallot. Her main symptoms were in the respiratory system, and chest X-ray also revealed the giant space-occupying lesion in the chest, which could've been misdiagnosed as a respiratory disease. After evaluation by the combination of echocardiography and cardiac computer tomography angiogram, the details of PSA were diagnosed, and surgical but not percutaneous intervention was selected. The exclusion of PSA successfully was performed by the femoral cannulation, exploratory through right ventriculotomy, closure of the defect using the Gore-Tex patch, and application of a retained drainage-tube inside the PSA.

Association of epicardial adipose tissue attenuation with coronary atherosclerosis in patients with a high risk of coronary artery disease.

BACKGROUND AND AIMS: Density may indicate some tissue characteristics and help reveal the role of epicardial adipose tissue (EAT) in coronary artery disease (CAD). Therefore, we assessed the association of EAT density with the coronary artery plaque burden in patients presenting with chest pain. METHODS: This retrospective cohort study comprised 614 patients (mean age 61 ±â€¯9 years, 61% males) with a high cardiovascular disease risk, who underwent cardiac computed tomography angiography. Density was reflected as attenuation. RESULTS: EAT attenuation was significantly associated with EAT volume with a negative Pearson's correlation coefficient and gradually increased across coronary artery calcium (CAC) scores of 0, 1-100, 101-400 and > 400. EAT attenuation was tightly associated with CAD risk factors, including age, sex, BMI, total cholesterol, neutrophil to lymphocyte ratios and CAC score. The association between EAT attenuation and CAC score was strengthened after adjusting for multivariable indices (OR 1.21, 95% CI 1.05-1.40, p = 0.01) and further adjusting for EAT volume (OR 1.26 95% CI 1.06-1.51, p<0.01). However, EAT attenuation was associated only with CAD presence (OR 1.32, 95% CI 1.02-1.69, p<0.05), CAC presence (OR 1.28, 95% CI 1.02-1.60, p<0.05), segment involvement score (OR 1.19, 95% CI 1.01-1.40, p<0.05) and segment stenosis score (OR 1.19, 95% CI 1.01-1.40, p<0.05) in the EAT volume- and multivariable-adjusted model. Additionally, EAT attenuation was not associated with significant coronary artery lesions and triple-vessel plaques. CONCLUSIONS: Higher EAT attenuation is associated with a higher risk of CAD.

Theoretical Investigation of the Hydrolytic Mechanism of α-Functionalized Alkoxysilanes as Effective Crosslinkers and the Difficulty of Deep Vulcanization in RTV Silicone Rubber.

The reactions between α-, γ-ethylenediaminemethyl trimethyl-ketoxime silane (α-, γ-EAMOS) and H2O were investigated on the geometries of stationary points, the reaction pathway (IRC), thermodynamic and kinetic analysis by density functional theory (DFT) at the B3LYP/6-311G (d, p) level. Interestingly, the results showed that the hydrolysis activity of α-EAMOS is higher than that of γ-EAMOS, due to the influence of an amino substituent in position α-C on silicon. α-EAMOS can be used as a superior crosslinker for room temperature vulcanized (RTV) silicone rubber to achieve rapid crosslinking without a toxic catalyst. Besides, compared with the reaction between α-EAMOS and H2O, the reactivity between α-EAMOS and hydroxy siloxane (HO⁻Si(CH3)2⁻OSiH3) was discussed. Particularly, it revealed that the deep vulcanization of RTV silicone rubber is difficult.

Impacts of Different Functional Groups on the Kinetic Rates of α-Amine Ketoximesilanes Hydrolysis in the Preparation of Room Temperature Vulcanized Silicone Rubber.

α-Amine ketoximesilanes are proven to be effective crosslinkers in the preparation of ketone-oxime one-component room temperature vulcanized (RTV) silicone rubber without the use of toxic metal catalyst. This work aimed to investigate the hydrolysis kinetic of α-amine ketoximesilanes, which is vitally important for the preparation of RTV silicone rubber. Five kinds of α-amine ketoximesilanes, namely α-(N,N-diethyl)aminomethyltri(methylethylketoxime)silane (DEMOS), α-(N,N-di-n-butyl)aminomethyltri(methylethylketoxime)silane (DBMOS), α-(N-n-butyl)aminomethyltri(methylethylketoxime)silane (n-BMOS), α-(N-cyclohexyl)aminomethyltri(methylethylketoxime)silane (CMOS) and α-(β-aminomethyl)aminomethyltri(methylethylketoxime)silane (AEMOS), were successfully obtained and confirmed using Fourier transform infrared spectrometer (FT-IR) and hydrogen-1 nuclear magnetic resonance ( ¹H NMR). Kinetics of hydrolysis reactions were measured by FT-IR and conductivity. Our results illustrated that the kinetic constant rates ranged from 12.2 × 10−4 s−1 to 7.6 × 10−4 s−1, with the decreasing order of DEMOS > n-BMOS > DBMOS > CMOS > AEMOS at the given temperature and humidity. Better performances of thermal stability could be achieved when using the α-amine ketoximesilanes as crosslinkers in the preparation of RTV silicon rubber than that of RTV silicone rubber with the use of methyltri(methylethylketoxime)silane (MOS) as a crosslinker and organic tin as a catalyst.

Correlation between Plasma Level of Monocyte Chemotactic Protein 1 and Acute Aortic Dissection.

OBJECTIVE: To investigate the potential association between monocyte chemotactic protein 1(MCP-1)in plasma and acute aortic dissection(AAD). METHODS: A total of 110 patients with Stanford type A AAD who had received emergent surgical treatment in Xiangya hospital from September 2011 to September 2014 were enrolled in as the study group;meanwhile,110 patients with simple hypertension who had received treatment in department of cardiology were chosen as the control group. The plasma level of MCP-1 was measured and then compared between these two groups. RESULTS: The plasma level of MCP-1 in the study group was(257.79±86.52)pg/ml,which was significantly higher than that in control group [(136.57±48.84)pg/ml](P<0.001). CONCLUSION: There may be a correlation between plasma MCP-1 level and AAD.

[Efficacies of tricuspid valve replacement versus repair for moderate-to-severe tricuspid regurgitation with right heart failure].

OBJECTIVE: To compare the efficacies of tricuspid valve replacement versus plasty for moderate-to-severe tricuspid regurgitation with right heart failure. METHODS: From January 2003 to June 2008, a total of 228 patients with right heart failure undergoing tricuspid valve operations were selected. And the procedures included tricuspid valve plasty (n=127) and tricuspid valve replacement (n=101). During a follow-up period of 65 months, their perioperative data were collected to evaluate the surgical outcomes. RESULTS: The abnormal liver function rate and average pulmonary artery systolic pressure in tricuspid valve plasty group were lower than those in tricuspid valve replacement group (P=0.023, 0.033). In replacement group, average aortic cross-clamping time, cardiopulmonary bypass time, ventilation time and stay length of intensive care unit (ICU), the usage of inotropic drug was significantly higher than repair group (P<0.01). The early complication rate (15.8%) and case fatality rate (6.3%) of repair group were much lower than those of replacement group (27.3%, 16.8%) (P=0.042, 0.011). Long-term follow-ups revealed that the tricuspid valve thrombosis rate in replacement group was higher than that in repair group (P=0.036). And the recurrence rate of moderate-to-severe tricuspid regurgitation in repair group was higher than that in replacement group (28.7% vs 8.8%) (P=0.011). The survival rate of patients in repair group was much higher than that of replacement group at 3 months, 1, 3, 5 years post-operation. However, the differences were not statistically significant (P=0.231, 0.089, 0.133, 0.078). CONCLUSION: For moderate-to-severe tricuspid regurgitation leading to right heart failure, the early efficacy of tricuspid valve plasty is much better than that of tricuspid valve replacement. The mid-term recurrence rate after tricuspid valve repair is higher than that of replacement.

Kank1 reexpression induced by 5-Aza-2'-deoxycytidine suppresses nasopharyngeal carcinoma cell proliferation and promotes apoptosis.

Kank1, which was first described as a potential tumor suppressor for renal cell carcinoma (RCC), mapped to 9p24.3 and encoded an ankyrin-repeat domain-containing protein. Its frequent deletion was found to be associated with several human malignant tumors, cerebral palsy, and neuronal and developmental diseases. However, its functional role in nasopharyngeal cancer (NPC) was still unknown. In the present study, we found that Kank1 expression was down-regulated in NPC cells than in human nasopharyngeal epithelial cell line NP69 and demethylating agent 5-aza-2'-deoxycytidine (5-aza-CdR) could improve its mRNA and protein expression level. Further studies demonstrated that DNA methylation might be the mainly cause for Kank1 decreased expression and restored Kank1 expression mediated by 5-aza-CdR played a key role in suppressing NPC cells growth and inducing its apoptosis. Our primary results revealed new function of Kank1 for NPC and implied that epigenetic regulation especially demethylation may have a potential value for NPC treatment.

Association of BTBD7 with Metastasis and Poor Prognosis in Non-Small-Cell Lung Cancer Patients.

Metastasis in lung cancer portends a poor prognosis, and the epithelial-mesenchymal transition (EMT) in lung cancer cells is considered a prerequisite to achieve metastatic potential. Recent studies indicate that BTB/POZ domain-containing protein 7 (BTBD7) regulates EMT-associated proteins in human malignancies and however, the role of BTBD7 in lung cancer have not been identified. In present study, we examined BTBD7 expression status and its association with unfavorable clinical features in non-small-cell lung cancer (NSCLC). Firstly, we studied the fresh specimens, and found that both mRNA and protein expression levels of BTBD7 in NSCLC tissue were significantly increased compared with the adjacent nontumorous lung tissue. Then, we determined BTBD7 protein expressions in the paraffin-embedded samples from NSCLC patients, and analyzed the relations of BTBD7 expression with clinicopathologic features of the patients. The results showed that incidence of metastasis in patients with positive BTBD7 expression was significantly higher than that in those with negative BTBD7 expression, and the positive BTBD7 expression rate in metastatic cases was significantly higher than that in non-metastatic ones; furthermore, Cox regression analyses revealed that BTBD7 was an independent risk factor for either metastasis or survival in NSCLC patients. Thus, we conclude that BTBD7 contributes to metastasis of NSCLC and BTBD7-positive NSCLC may have a high potential for metastasis and thereby a poor prognosis.