[Current status of the clinical practice and analysis on the ratioanl prescription of antiarrhythmic drugs in Chinese patients with atrial fibrillation: Results from the Chinese Atrial Fibrillation Registry (CAFR) trial]

Objective: To explore the practice patterns and the related factors of oral antiarrhythmic drug (AAD) treatment in Chinese patients with atrial fibrillation (AF), and to evaluate the compliance of AAD application to atrial fibrillation management guidelines. Methods: From August 2011 to August 2016, medical records from 18 014 patients with AF were analyzed based on data from the Chinese Atrial Fibrillation Registry trial. Patients were divided into AAD group (7 788 cases, 43.23%) and non-AAD group (10 226 cases, 56.77%) according to whether AAD was used at baseline or at the time of first use during follow-up. Amiodarone (4 129 cases, 53.02%) and propafenone (3 211 cases, 41.23%) were the mostly prescribed AAD and subgroup analysis was performed accordingly. Medical records were analyzed by random forest regression to evaluate the use of AAD and related factors in patients with AF, and the rationality of AAD was analyzed according to the guidelines for the management of atrial fibrillation. Result: A total of 18 014 patients were included in this study, of which 60.48% (10 895/18 014) were male patients, 22.65% (4 081/18 014) were elderly patients(≥75 years old), there were 7 788 patients (43.23%) in AAD group, and 10 226 patients(56.77%) in non-AAD group. Compared with the non-AAD group, the elderly patients (≥75 years old, 13.74%(1 070/7 788) vs. 29.44%(3 011/10 226)), persistent AF (28.95% (2 250/7 788) 45.80% (4 683/10 226)), heart failure(8.29% (646/7 788) vs. 21.95% (2 245/10 226)), stroke and (or) TIA(12.15% (946/7 788) vs. 19.95% (2 040/10 226)), renal dysfunction(16.36%(1 274/7 788) vs. 29.37% (3 003/10 226)), and high thromboembolism risk(60.17% (4 748/7 788) vs. 76.40% (7 813/10 226)) were less prevalent in the AAD subgroup (P<0.001). Multivariate analysis showed that patients in tertiary hospitals (OR=3.72, 95%CI 3.17-4.37) were more likely to use AAD, elderly patients (≥75 years old, OR=0.47, 95%CI 0.39-0.55), persistent atrial fibrillation (OR=0.66, 95%CI 0.60-0.72), and patients with heart failure (OR=0.54, 95%CI 0.47-0.63), stroke and (or) TIA (OR=0.77, 95%CI 0.68-0.87), renal dysfunction (OR=0.75, 95%CI 0.59-0.95) and high thromboembolism risk(OR=0.7, 95%CI 0.58-0.84) were more likely not to use AAD(P<0.05). In the AAD group, amiodarone and propafenone were the most commonly used AAD, accounting for 53.02% (4 129/7 788) and 41.23% (3 211/7 788), respectively. Multivariate analysis showed that patients with persistent atrial fibrillation (OR=4.57, 95%CI 3.94-5.29) and coronary heart disease (OR=4.14, 95%CI 3.03-5.64), heart failure (OR=2.07, 95%CI 1.48-2.89), non-ischemic cardiomyopathy (OR=4.84, 95%CI 2.41-9.73) were more likely to use amiodarone, and those with normal left ventricular ejection fraction (OR=0.31, 95%CI 0.15-0.65) and low thromboembolism risk (OR=0.78, 95%CI 0.63-0.97) were more likely to use propafenone (P<0.001). The overall incidence of AAD treatment, which was not indicated by the guidelines was 6.5% (480/7 340); 5.1% (212/4 129) in the amiodarone group and 8.3% (268/3 211) in the propafenone group, respectively. Compared with the rational AAD use group, the proportion of irrational drug use was higher in the elderly (≥75 years old) (20.4% (98/480) vs. 12.9% (887/6 860)), patients of high thromboembolism risk (77.1% (379/480) vs. 59.0% (4 047/6 860)), and in non-tertiary hospitals (7.1% (34/480) vs. 3.3% (299/6 860)), but lower in men(50.8% (244/480) vs. 64.5% (4 427/6 860)), P<0.001. Conclusions: The patients with paroxysmal atrial fibrillation, who were treated with AAD, were mostly patients with fewer complications, and the patients who were treated with amiodarone were mostly patients with persistent atrial fibrillation, patients were more likely to complicate with organic heart disease. The incidence of AAD that do not comply with the guidelines was low, and it was more common in non-tertiary hospitals and the elder patients with high thromboembolism risk.

Urgent-start peritoneal dialysis and patient outcomes: a systematic review and meta-analysis

OBJECTIVE

The present study was aimed at illustrating short- or long-term patient outcome among individuals with urgent-start peritoneal dialysis (PD) compared with those with conventional PD.

MATERIALS AND METHODS

We searched the PubMed, EMBASE, Cochrane Controlled Trials Register and China National Knowledge Infrastructure databases. Cohort studies were investigated comparing the effects of urgent start of PD (<14 days after catheter insertion) to those of conventional start of PD (≥14 days after catheter insertion). Risks of bias across studies were evaluated using Newcastle-Ottawa Quality Assessment Scale. We calculated the pooled risk ratios and mean differences with 95% confidence intervals for dichotomous data and continuous data, respectively.

RESULTS

Six studies involving 1,242 patients were identified. Compared with conventional PD, urgent-start PD was not associated with a high mortality (RR: 1.25, 95% CI: 0.92 to 1.69; I2=0%, p=0.99) and a higher prevalence of overall mechanical complications (RR: 1.79, 95% CI: 0.85 to 3.78; p=0.12; I2=64%, p=0.02). However, urgent-start PD was associated with a higher prevalence of leakage (RR: 6.72, 95% CI: 2.11 to 21.32; I2=0%, p=0.60). In terms of infectious complications, data analysis of the fixed-effects model showed no difference between the two groups. (RR: 1.36, 95% CI: 0.90 to 2.05, p=0.14), regardless of peritonitis (RR: 1.36, 95% CI: 0.90 to 2.05, p=0.14; I2=0%, p=0.70) or other infections (RR: 1.15, 95% CI: 0.49 to 2.69, p=0.99; I2=0%, p=0.75).

CONCLUSIONS

Urgent-start PD was not associated with a higher risk of mortality and dialysis-related complications. However, compared with conventional PD, an urgent start of PD may increase the risk of a leak.

Study on the characteristics and mechanism of pulsed laser cleaning of polyacrylate resin coating on aluminum alloy substrates

The behavior of paint removal with a pulsed laser has been investigated using an Nd:YAG fiber laser. Experimental and theoretical analyses are conducted to reveal the underlying mechanism of the paint removal. The results show that the depth, radius, and volume of the pit formed by a single pulse become larger with increases in the energy density. The ideal parameters for the complete removal of paint have been achieved. During the paint removal, burning occurred over the surface, and the variation in element content has been attributed to the absorption of laser energy. Under the action of the pulsed laser, there was breakage and rearrangement of chemical bonds such as C-C, C-N, and C-O in the molecular chain of the polyacrylate paint coating. Through these analyses, the paint removal mechanism was shown to be based on chemical bond breakage, combustion, and mechanical action provided by the thermal expansion and plasma shock.

MiRNA-153-3p promotes gefitinib-sensitivity in non-small cell lung cancer by inhibiting ATG5 expression and autophagy

OBJECTIVE

To clarify the function of miRNA-153-3p in gefitinib-sensitive non-small cell lung cancer (NSCLC) and the underlying mechanism.

PATIENTS AND METHODS

The expressions of miRNA-153-3p, LC3B and ATG5 in gefitinib-resistant and gefitinib-sensitive NSCLC tissues were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between miRNA-153-3p to LC3B or ATG5 was analyzed. We evaluated autophagy level in gefitinib-resistant NSCLC cells by calculating the percentage of PC-9/GR and HCC827/GR cells with positive GFP-LC3, as well as determining autophagy-related gene levels. The potential binding between ATG5 and miRNA-153-3p were verified by Dual-Luciferase reporter gene assay. The regulatory effects of miRNA-153-3p/ATG5 on gefitinib-sensitivity and apoptosis were finally examined by cytotoxicity assay and Annexin V-fluorescein isothiocyanate (FITC)/Propidium Iodide (PI) staining, respectively.

RESULTS

MiRNA-153-3p was lowly expressed in gefitinib-resistant NSCLC relative to the gefitinib-sensitive ones. MiRNA-153-3p was negatively correlated with autophagy activity marker LC3B in gefitinib-resistant NSCLC patients. Compared with parental cells, gefitinib-resistant NSCLC cell lines PC-9/GR and HCC827/GR presented a lower level of miRNA-153-3p and a higher level of autophagy. The overexpression of miRNA-153-3p greatly inhibited autophagy level. ATG5 could directly bind to miRNA-153-3p, and ATG5 was highly expressed in gefitinib-resistant NSCLC. The correlation analysis found a negative correlation between ATG5 and miRNA-153-3p and a positive correlation between ATG5 and LC3B in gefitinib-resistant NSCLC. More importantly, ATG5 reversed the regulatory effects of miRNA-153-3p on autophagy, gefitinib-sensitivity and apoptosis of PC-9/GR and HCC827/GR cells.

CONCLUSIONS

MiRNA-153-3p is lowly expressed in gefitinib-resistant NSCLC patients. The overexpression of miRNA-153-3p enhances gefitinib-sensitivity in NSCLC by inhibiting autophagy via downregulating ATG5.

Systematic review and meta-analysis of the association between dairy consumption and the risk of hip fracture: critical interpretation of the currently available evidence

In the present meta-analysis, reductions in the risk of hip fracture with milk consumption were only observed among American adults, but not among Scandinavian adults, possibly because milk products are more commonly fortified with vitamin D in the former population than in Scandinavian countries. The reduction in the risk of hip fracture was also observed with yogurt consumption, which is often associated with healthy lifestyles and dietary patterns that contribute to improved bone health.

INTRODUCTION

Although dairy products contain bone-beneficial nutrients, the association between dairy consumption and the risk of hip fracture remains equivocal. Fueling this uncertainty, the elevated risk of hip fracture in association with milk consumption was observed in a cohort of Swedish women. A systematic review and meta-analysis of prospective cohort studies was performed to critically evaluate the association, or lack thereof, between dairy consumption (milk, yogurt, and cheese) and the risk of hip fracture.

METHODS

A random effects model was used to generate the summary relative risks (RRs) with their 95% confidence intervals (CIs) for the associations of interest.

RESULTS

In the meta-analysis of the highest versus lowest category of consumption, higher consumption of yogurt (RR 0.78, 95% CI 0.68, 0.90), but not milk (RR 0.86, 95% CI 0.73, 1.02) or cheese (RR 0.85, 95% CI 0.66, 1.08), was associated with a lower risk of hip fracture. For milk, the reduced risk of fracture with higher milk consumption was observed in the USA (RR 0.75, 95% CI 0.65, 0.87), but not in Scandinavian countries (RR 1.00, 95% CI 0.85, 1.17). These findings were further supported by the fact that American studies (RR 0.93, 95% CI 0.88, 0.98; per 1 glass/day), but not Scandinavian studies (RR 1.01, 95% CI 0.95, 1.07; per 1 glass/day), demonstrated a linear association between milk consumption and the risk of hip fracture.

CONCLUSIONS

The cumulative evidence from prospective cohort studies reassuringly suggests that the risk of hip fracture may not be elevated among people who consume milk, yogurt, and cheese, and that a greater consumption of milk or yogurt may even be associated with a lower risk of hip fracture depending on the factors that may differ across the population of interest.

The expression and clinical significance of miRNA-99a and miRNA-224 in non-small cell lung cancer

OBJECTIVE

To investigate the expression and clinical significance of miRNA-99a and miRNA-224 in the serum of patients with non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

83 patients with NSCLC, who were diagnosed and treated in our hospital from January 2014 to September 2017, were included in the experiment group. 79 patients, who made health check up, were included in the control group. The quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) technique was used to test the expressions of miRNA-99a and miRNA-224 in the serum of the patients in the two groups, and the relationship between the expression levels of miRNA-99a and miRNA-224 and the clinicopathological features of the patients with NSCLC was analyzed; the correlation between the expression of miRNA-99a and the expression of miRNA-224 in NSCLC was also analyzed.

RESULTS

The expression level of miRNA-99a in the patients with NSCLC was significantly lower than that in the patients in the normal control group; the differences were statistically significant (p<0.001). The expression level of miRNA-224 in the patients with NSCLC was markedly higher than that in the patients in the normal control group; the differences were statistically significant (p<0.001). The expression level of miRNA-99a in the patients with NSCLC was remarkably correlated with pathological stage, the presence or absence of lymph node metastasis and tissue differentiation (p<0.001). The expression level of miRNA-224 in the patients with NSCLC was significantly correlated with pathological stage, the presence or absence of lymph node metastasis and pathological grade (p<0.001). The results of partial correlation analysis showed that the expression levels of miRNA-99a and miRNA-224 were negatively correlated with each other in NSCLC (r=-0.985, p<0.001).

CONCLUSIONS

MiRNA-99a and miRNA-224 may be involved in the development and progression of NSCLC. MiRNA-99a is associated with NSCLC pathological stage, lymph node metastasis and tissue differentiation, while miRNA-224 is associated with NSCLC pathological stage, lymph node metastasis and pathological grade. MiRNA-99a and miRNA-224 can be used as clinical monitoring indicators for NSCLC.

Effect of miR-34a on resistance to sunitinib in breast cancer by regulating the Wnt/β-catenin signaling pathway

OBJECTIVE

The aim of this study was to investigate the influence of micro ribonucleic acid (miR)-34a on resistance to sunitinib in breast cancer, and to explore its possible underlying mechanism.

MATERIALS AND METHODS

Breast cancer MCF-7 cells were transfected with miR-34a inhibitor or mimics to downregulate or upregulate the expression of miR-34a. Then, the transfected cells were treated with sunitinib. Next, transwell assay was applied to detect the changes in cell invasion ability. Cell viability was measured via cell counting kit-8 (CCK8) assay. Dual-Luciferase reporter gene assay was employed to determine the interaction between miR-34a and the Wnt/β-catenin signaling pathway. The immunoblotting assay was used to measure the expression changes of proteins in the pathway.

RESULTS

The overexpression of miR-34a significantly reduced the invasive ability of MCF-7 cells after treatment with sunitinib. After miR-34a expression was downregulated, the sensitivity of MCF-7 cells to sunitinib was significantly lowered. MiR-34a interacted with the 3'-untranslated region (3'-UTR) on Wnt1. Meanwhile, the overexpression of miR-34a remarkably downregulated the messenger RNA (mRNA) and the protein levels of Wnt1, whereas upregulated the expressions of Wnt1 and β-catenin.

CONCLUSIONS

MiR-34a affects the sensitivity to sunitinib in breast cancer by regulating the Wnt/β-catenin signaling pathway.

The potential biological functions of circular RNAs during the initiation of atresia in pig follicles

The specific expression profile and function of circular RNAs (circRNAs) in mammalian ovarian follicles, especially during the atresia process, are unclear. In this study, genome-wide deep circRNA sequencing was applied to screen circRNAs in healthy and early atretic antral follicles in pig ovaries. A total of 40,567 distinct circRNAs were identified in follicles, among which 197 circRNAs (108 upregulated and 89 downregulated) were significantly shifted during the early atresia process. Most differentially expressed circRNAs (DECs) lacked protein-coding potential. Annotation analysis of the DECs revealed 162 known host genes, or noncoding RNAs, and 10 intergenic regions. The key pathways in which these host genes are involved include the focal adhesion-PI3K-Akt-mTOR signaling pathway, vascular endothelial growth factor A (VEGFA)-vascular endothelial growth factor receptor 2 signaling pathway and transforming growth factor-beta signaling pathway. Further comparison analysis between host genes of DECs and the differentially expressed linear messenger RNA transcripts revealed the cotranscription of circRNAs and their linear mRNAs in inhibin beta units (INHBA and INHBB), glutathione S-transferase (GSTA1), and VEGFA. In addition, we predicted 196 pairs of potential circRNA-micro RNA (miRNA) interactions among 77 DECs and 101 porcine miRNAs. We have identified 16 functional miRNAs by comparing the 101 miRNAs to the functional miRNAs reported in mammal ovarian follicle atresia and granulosa cell apoptosis studies. Our study adds new knowledge to circRNA distribution profiles in pig ovarian follicles, offers a valuable reference for transcriptomic profiles in the initiation of follicular atresia, highlights warranted circRNAs for further functional investigation, and provides possible biomarkers for ovarian dysfunctions.

[Value of left ventricular myocardial strain derived from cardiac magnetic resonance tissue tracking on differentiating constrictive pericarditis from restrictive cardiomyopathy]

Objective: To compare left ventricular myocardial mechanics detected by cardiac magnetic resonance tissue tracking(CMR-TT) between patients with constrictive pericarditis(CP) and restrictive cardiomyopathy(RCM),and see if those can be used to differentiate CP from RCM patients. Methods: A total of 23 patients with CP, 20 patients with RCM, who hospitalized in Beijing Anzhen Hospital from January 2014 to April 2019 were included in this study and 25 healthy subjects served as control group, all subjects underwent cardiac magnetic resonance examination. Myocardial mechanics were evaluated by 2-dimensional(2D) and 3-dimensional(3D) CMR-TT in terms of global longitudinal strain(GLS), circumferential strain(GCS), radial strain(GRS) and the lateral wall strain to septal wall strain ratio(lateral/septal ratio) of basal, mid-cavity and apical. The diagnostic area under the receiver operating characteristic curve (ROC) was evaluated for differentiating CP from RCM. Results: Age, sex and heart rate were similar between CP and RCM patients(all P>0.05). 2D-GLS, 3D-GLS, GCS and GRS in CP and RCM groups were significantly lower than those in normal control group(all P<0.05).3D-GLS value was significantly lower in RCM patients than in CP patients(P<0.05), the area under the curve (AUC)=0.787(sensitivity 80%, specificity 78%). 3D-GCS was significantly lower in CP group than in RCM group(P<0.05), the AUC=0.737(sensitivity 80%, specificity 65%). However, there was no significant difference between CP and RCM in 3D-GRS(P>0.05). Compared with RCM, the circumferential and radial lateral/septal ratios of the basal were significantly lower in CP group than in RCM group(both P<0.05), AUC=0.737(sensitivity 70%, specificity 83%) and 0.737 (sensitivity 60%, specificity 87%), respectively. The left ventricular myocardial mechanics strain curve of the CP,RCM and normal control were different. The CP patients presented as " rapidly down-a platform" form, the RCM presented as "slowly down" form, and normal control presented as "rapidly down" form. Conclusion: Evaluating the differences in the diastolic process of left ventricular myocardium and left ventricular myocardial mechanics strain curve is helpful to differentiate CP from RCM patients.

Microwave Absorption Properties of Magnetite Particles Extracted from Nickel Slag

The utilization of nickel slag has attracted much attention due to its high-content of valuable elements. As a part of these efforts, this work focuses on whether magnetite crystals, obtained from nickel slag via molten oxidation, magnetic separation, and ball-milling can be used as a microwave absorber. The composition, morphology, microstructure, magnetic properties, and microwave absorption performance were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), and vector network analysis (VNA). The results reveal that the magnetite crystals exhibit excellent microwave absorption properties because of the synergistic action between dielectric loss and magnetic loss. The minimum reflection loss (RL) of the particles obtained after 6 h ball-milling reaches −34.0 dB at 16.72 GHz with thickness of 5 mm. The effective frequency bandwidth (RL ≤ −10 dB) is 4.8–5.4 GHz and 15.9–17.6 GHz. Interfacial polarization of the particles could play a crucial role in improving absorbing properties because several components contained in the particles can dissipate electromagnetic wave effectively. The current study could show great potential in the preparation of magnetite crystals and utilization of nickel slag.

[Risk factors for recurrent hospitalizations of patients with atrial fibrillation]

Objective: To determine the predictors of recurrent hospitalizations among atrial fibrillation (AF) patients. Methods: We analyzed data from the Chinese Atrial Fibrillation Registry (CAFR), a prospective cohort study involving non-valvular atrial fibrillation (NVAF) patients from Augest 2011 to December 2017. A total of 5 349 NVAF patients with a minimum of 48 months follow-up were included for analysis. Data including patient demographics, complications, medical and ablation history were collected. The maximum number of all-cause hospitalizations within one-year for each patient served as the primary endpoint. Patients hospitalized less than twice within one-year were defined as non-recurrent hospitalizations group, those hospitalized at least twice within one-year were definned as recurrent hospitalizations group. Logistic regression model was used to identify associated risk factors for recurrent hospitalizations. Results: Of 5 349 NVAF patients, those hospitalized for 0, 1, 2, 3, 4 and at least 5 times within one-year was 2 703 (50.5%), 1 776 (33.2%), 642 (12.0%), 161(3.0), 52 (1.0%), 15 (0.3%), respectively. Eight hundred and seventy (16.3%) patients were included in recurrent hospitalizations group, 4 479 (83.7%) patients were included in non-recurrent hospitalizations group. Compare with non-recurrent hospitalizations group, patients in recurrent hospitalizations group was more likely to be older and female, more frequently had a history of hypertension, heart failure, coronary heart disesase, ischaemic stroke/transient ischaemic attack, diabetes mellitus, peptic ulcer, a AF duration for more than 1 year, medication including drugs for ventricular rate control, statin, angiotensin-converting enzyme inhibitors (ACEI)/angiotensin receptor blocker (ARB) and higher CHA(2)DS(2)-VASc scores (P<0.05), but less frequently had higher education, a history of drinking, smoking and ablation (P<0.05). Multivariable analysis showed that age 50-64 (OR=1.47, 95%CI 1.20-1.80), age≥65 (OR=1.89, 95%CI 1.50-2.38), female (OR=1.21, 95%CI 1.01-1.46), hypertension history (OR=1.42, 95%CI 1.16-1.74), heart failure history (OR=1.73, 95%CI 1.37-2.18), coronary heart disease history (OR=1.63, 95%CI 1.31-2.03), peptic ulcer history (OR=2.00, 95%CI 1.18-3.39) were independent risk factors for recurrent hospitalizations, while higher education (college or above) (OR=0.82, 95%CI 0.69-0.99) was the protective factor for recurrent hospitalizations. Conclusions: Nearly 1 in 6 of AF patients were admitted to hospital more than once within one year in this NVAF cohort. Age≥50, female, hypertension history, heart failure history, coronary heart disease history, peptic ulcer history are associated with an increased risk of recurrent hospitalizations.

[Relationship between C-reactive protein level and incidence of left atrial spontaneous echocardiographic contrast in patients with nonvalvular atrial fibrillation]

Objective: To investigate the relationship between high sensitivity C-reactive protein (hs-CRP) level and incidence of left atrial spontaneous echocardiographic contrast (LASEC) in the patients with nonvalvular atrial fibrillation (AF). Methods: Four hundred and ninety consecutive patients with nonvalvular atrial fibrillation who underwent radiofrequency ablation for the first time from January 1, 2018 to June 30, 2018 in the Department of Cardiology, Beijing Anzhen Hospital were enrolled. According to the results of transesophageal echocardiography before radiofrequency ablation, patients were divided into the group without LASEC (n=338) and the group with LASEC (n=152). hs-CRP was determined by latex enhanced immunoturbidimetry. The relationship between hs-CRP and LASEC in patients with nonvalvular atrial fibrillation was investigated by univariate and multivariate logistic analysis. Results: LASEC was detected in 152 (31%) of 490 patients. Significant differences in age, type of atrial fibrillation, previous embolic events, fibrinogen, D-dimer, the left atrial anteroposterior diameter and CHA(2)DS(2)-VASc scores were found between patients with and without LASEC (all P<0.05). Compared with the group without LASEC, the serum hs-CRP level was significantly higher in the group with LASEC (3.16 (1.30, 5.23) mg/L vs. 0.67 (0.37, 1.48) mg/L, P<0.001). Multivariate logistic regression analysis showed that hs-CRP (OR=1.136, 95%CI 1.060 - 1.217, P<0.001) and D-dimer (OR=1.040, 95%CI 1.011 - 1.070, P=0.007) were independent determinants for LASEC in this patient cohort. Conclusions: hs-CRP is an independent determinant for LASEC in patients with nonvalvular atrial fibrillation. Inflammation may thus be involved in the formation of prethrombotic state in patients with nonvalvular atrial fibrillation.

[Impact of change of ideal cardiovascular behavior and related factors on healthy vascular aging]

Objective: To investigate the impact of change of ideal cardiovascular behavior and related factors on healthy vascular aging(HVA). Methods: This study was a multi-center cross-sectional survey. Six thousand three hundred and sixteen participants who underwent at least 2 healthy examinations from 2006 to 2015 at 11 hospitals, including Kailuan Hospital and so on, and examined brachial-ankle pulse wave velocity (baPWV) during 2010 and 2016, with available information about cardiovascular behavior and factors were included. The cardiovascular health score (CHS) was calculated. Basic CHS was collected from the first examination. The second CHS derived from the healthy examination in the same year of baPWV examination. Change of cardiovascular health score (ΔCHS) was calculated. Participants were defined into 5 groups according to ΔCHS, namely ΔCHS≤-2 (n=2 166), ΔCHS=-1 (n=1 284), ΔCHS=0 (n=1 187), ΔCHS=1 (n=860), and ΔCHS≥2 (n=819). Participants' characteristics, value of baPWV and proportion of HVA were compared among different groups. Multiple logistic regression analysis was used to investigate the association between ΔCHS and HVA. The ΔCHS was recalculated and included in multiple logistic regression analysis model again after each component of the cardiovascular health metrics was removed separately in order to investigate effects of removal factors on HVA by observing changes in effect values. Results: The percentage of the participants with HVA in the group of ΔCHS≤-2, ΔCHS=-1, ΔCHS=0, ΔCHS=1 and ΔCHS≥2 were 23.3%(505/2 166), 27.8%(357/1 284), 28.7%(341/1 187),31.9%(274/860) and 33.9%(278/819), respectively. After adjustment for age, sex, income, education, alcohol consumption and the basic CHS, a significant positive association between ΔCHS and proportion of participants with HVA was observed (OR=1.50, 95%CI 1.44-1.56). Multiple regression analysis after removing each single cardiovascular behavior or factor showed that the OR value decreased as follow systolic blood pressure (OR=1.04, 95%CI 1.00-1.09), fasting blood glucose (OR=1.14, 95%CI 1.09-1.18), physical exercise (OR=1.16, 95%CI 1.11-1.21), salt intake (OR=1.17, 95%CI 1.12-1.22), body mass index (OR=1.18, 95%CI 1.13-1.23), smoking(OR=1.18, 95%CI 1.13-1.23) and total cholesterol (OR=1.20, 95%CI 1.16-1.24). Conclusion: The improvement of every ideal cardiovascular behavior and factor is associated with the increase of the proportion of HVA population.

Development of a rapid, one-step-visual method to detect Salmonella based on IC-LAMP method

BACKGROUND

Salmonella can cause serious human gastroenteritis and is frequently isolated from various food samples. The cell culturing, immunoassay, and polymerase chain reactions (PCR) are the current methods to detect such pathogenic agents. However, these methods are time-consuming and labor-intensive, and thus unavailable for rapid-monitoring of Salmonella.

AIMS

This study aimed to develop an immunocapture-loop-mediated isothermal amplification (IC-LAMP) for rapid and sensitive detection of Salmonella.

METHODS

Salmonella was used as antigen to produce monoclonal antibody (mAb) and mAbs were prepared via subcloning three times. The mAb 1B12 with high affinity was coated on the surface of the immuno-magnetic beads (IMBs) to capture Salmonella. The enriched products (IMBs-Salmonella) were used for LAMP using the special primers targeted the conserved invA gene of Salmonella.

RESULTS

The IC-LAMP was developed based on mAb 1B12 and LAMP. Targeting the conserved invA gene of Salmonella, the detection time was shortened to 50 min from three days. If the reaction contains Salmonella, the green fluorescence and the trapezoidal strip can be clearly observed. Importantly, the method combines the specificity of antibody and LAMP with a detection limit of 5 CFU/ml in artificially contaminated water and milk. The specificity of this method was demonstrated by testing other similar bacteria. The results indicate that the IC-LAMP reacts only with Salmonella and does not cross-react with other similar bacteria.

CONCLUSION

The IC-LAMP assay developed here is a rapid, sensitive, one-step-visual method to screen for the presence of Salmonella in food samples. This method is faster than traditional PCR, LAMP, and other methods, and can be used as a primary screening method for the detection.

[Clinical characteristics of left atrial appendage thrombus in patients with hypertrophic cardiomyopathy and non-valvular atrial fibrillation]

Objective: To investigate the incidence and clinical characteristics of left atrial appendage (LAA) thrombus in patients with hypertrophic cardiomyopathy (HCM) and non-valvular atrial fibrillation (AF) . Methods: Data from 10 440 patients with AF who had undergone transesophageal echocardiography (TEE) before cardioversion or catheter ablation at Beijing Anzhen Hospital from April 2006 to December 2018 were retrospectively screened. Two hundred and five HCM patients were included, 820 AF patients with the same CHA(2)DS(2)-VASc score over the same period were selected as the control group. HCM patients were divided into two subgroups based on presence or absence of LAA thrombus/sludge. The baseline of clinical information, transthoracic echocardiographic and TEE measures were compared among all the groups. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of left atrial diameter (LAD) for LAA thrombus/sludge. Multivariate logistic regression analysis was applied to analyze the correlative factors of LAA thrombus/sludge in HCM patients. Results: The incidences of LAA thrombus or sludge were higher in HCM group than in control group (10.7% (22/205) vs. 0.7% (6/820); 8.8% (18/205) vs.7.0% (57/820), P<0.001) . In HCM patients, LAD was significantly larger in LAA thrombus/sludge subjects than in those without thrombus/sludge ((48.9±5.1)mm vs. (45.2±6.1) mm, P<0.001). CHA(2)DS(2)-VASc score was similar between the two subgroups ((2.0±1.4) vs. (1.8±1.4), P>0.05). There was no difference in the rate of patients with a CHA(2)DS(2)-VASc scores ≥2 between the subgroups(62.5% (25/40) vs. 57.0% (94/165), P=0.525). The incidences of LAA thrombus in HCM and AF patients with CHA(2)DS(2)-VASc scores of 0, 1 and 2 were 8.8% (3/34) , 9.6% (5/52) , 11.8% (11/119) , respectively; and the rate of LAA sludge were 8.8% (3/52) , 7.7% (4/52) , 9.2% (11/119) , respectively. The cut off value of LAD for the diagnosis of LAA thrombus/sludge was 44.5 mm. Multivariate logistic regression analysis showed that LAD≥44.5 mm (OR=5.134, 95%CI 1.862-14.156, P=0.002) , non-paroxysmal AF (OR=2.782, 95%CI 1.238-6.252, P=0.013) , previous thromboembolism or stroke (OR=1.820, 95%CI 0.774-4.227, P=0.017) were independent determinants of LAA thrombus/sludge. Conclusions: The incidence of LAA thrombus/sludge is higher in patients with HCM and AF than in AF patients without HCM. The CHA(2)DS(2)-VASc score is similar between HCM and AF patients with LAA thrombus/sludge and those without thrombus/sludge. Patients with CHA(2)DS(2)-VASc score 0-1 are also likely to suffer LAA thrombus/sludge. Left atrial enlargement is associated with LAA thrombus/sludge.

One-Pot Synthesis of Doped-Polypyrrole/Fe₃O₄ Nanosphere Composites and Their Microwave Absorption Performance

Doped-polypyrrole/Fe₃O₄ (D-PPy/Fe₃O₄) nanospheres were successfully synthesized via a onepot process. In this process, polyvinyl alcohol (PVA) plays an important role in the construction of polypyrrole nanoparticles, and Fe³⁺ ions were the oxidant and the only raw resource of Fe₃O₄. The morphology, magnetic properties, and electromagnetic microwave absorption properties of D-PPy/Fe₃O₄ composites were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), a vibrating sample magnetometer (VSM) and a vector network analyser (VNA). The results indicate that D-PPy/Fe₃O₄ nanospheres become more disperse and regular due to the addition of PVA. The influence of the mass ratio of PVA to pyrrole on the microwave absorption performance of the D-PPy/Fe₃O₄ composites was also investigated. When the mass ratio of PVA/pyrrole was 0.75:1, the minimum reflection loss (RL_min) value of the D-PPy/Fe₃O₄ composites reached -41.3 dB at 7.7 GHz with a thickness of 3.0 mm. The microwave interference cancellation of interface reflection, nature resonance loss and current loss are the main reasons for the loss of electromagnetic microwaves for the as-prepared D-PPy/Fe₃O₄ composites.