[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.

[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.

Measurement method by inferring the thrust from the stress of the cantilever beam based on the photoelasticity theory

A new, to the best of our knowledge, thrust measurement system based on the photoelasticity theory has been developed to infer the thrust from the stress of the cantilever beam. In this method, the cantilever beam is employed as the loading element to convert the low thrust into high stress, and the modified dynamic photoelasticity is used to infer the stress value of the cantilever beam from the Stokes parameters of the emergent light. The experimental results validated that the thrust stand could measure the thrust in the range of millinewton or millisecond, and the thickness of the beam was negatively correlated with the measurement accuracy. The average errors of the experimental measurements for ampere forces were higher than 25 mN and the pulse ampere forces whose widths were longer than 45 ms were less than ${\pm 5}\% .$±5%. As for the real plasma discharges, the errors of the measured thrust were less than ${\pm 10}\% $±10%.

Paclitaxel inhibits the progression of cervical cancer by inhibiting autophagy via lncRNARP11-381N20.2

OBJECTIVE

To observe the effect of paclitaxel on the autophagy of human cervical cancer cell lines by the expression regulation of lncRNARP11-381N20.2 as well as to explore the interaction and relationship between autophagy, proliferation, and apoptosis of cervical cancer cells.

MATERIALS AND METHODS

Genome-wide expression profiles of tumors and their susceptibility to drugs were downloaded through TCGA database to find differentially expressed lncRNA RP11-381N20.2 in chemosensitive sensitive and insensitive groups. Expression of RP11-381N20.2 in 60 cervical cancer tissues and 30 normal tissues was detected by qRT-PCR. The relationship between the expression of RP11-381N20.2 and the clinicopathological parameters of lung cancer was statistically analyzed. The recombinant plasmid pcDNA-RP11-381N20.2 and pcDNA-NC of RP11-381N20.2 were transfected into SiHa cells by lipofectamine, respectively. The autophagy and phenotypic effects were observed. Cell proliferation was determined by colony formation assay. Apoptosis was detected by flow cytometry. Western blot was conducted to detect expressions of autophagy-related proteins.

RESULTS

Genome-wide expression profiles of chemotherapy-sensitive and insensitive data in patients with cervical cancer in TCGA database were analyzed by edger package, results showed that the expression of lncRNA RP11-381N20.2 was significantly lower in the chemotherapy-insensitive group. qRT-PCR results showed that the expression of RP11-381N20.2 in cervical cancer was decreased, and the total survival time of patients was positively correlated with the expression of RP11-381N20.2. RP11-381N20.2 was associated with TNM (tumor node metastasis) staging and tumor size. Biological functions of SiHa cells showed that the expression of RP11-381N20.2 was negatively correlated with the treatment time and dose of paclitaxel. Colony formation assay showed that paclitaxel could inhibit the proliferation of cervical cancer cells in a dose-dependent manner. Flow cytometry showed that paclitaxel induced apoptosis of cervical cancer cells, which was more promoted after combination with RP11-381N20.2. Western blot results suggested that paclitaxel could induce autophagy in cervical cancer cells in a time- and dose-dependent manners. Paclitaxel combined with RP11-381N20.2 could significantly increase apoptosis of cervical cancer cells.

CONCLUSIONS

During the killing process of paclitaxel on cervical cancer SiHa cells, cell autophagy would affect the efficacy, after overexpression of RP11-381N20.2 in SiHa cells, autophagy induced by paclitaxel was inhibited, thereby enhancing the killing effect of paclitaxel on tumor cells.

MicroRNA-574 enhances doxorubicin resistance through down-regulating SMAD4 in breast cancer cells

OBJECTIVE

Drug resistance has become an important factor that threatens the survival and prognosis of patients with breast cancer, especially in patients with advanced breast cancer. Several microRNAs have been proved to participate in the resistant process; however, the role of miR-574 in doxorubicin (Dox) resistant breast cancer is still unclear.

PATIENTS AND METHODS

Quantitative Real-time poly chain reaction (qRT-PCR) was employed to detect the expression level of miR-574 in breast cancer Dox-resistant MCF-7/Adr cell line and parental MCF-7 cell line. Using miR-574 mimics and inhibitors, miR-574 level was up- or down- regulated. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was handled to detect the IC50, and flow cytometric analysis was employed to measure the apoptosis and cell circle. Dual-luciferase and Western-blot experiments were applied to verify the direct target gene of miR-574.

RESULTS

miR-574 expression level was significantly higher in MCF-7/Adr cells compared to normal MCF-7 cells. Up-regulation of miR-574 level in MCF-7 cells promoted the cell growth and G0/G1-to-S phase transition but inhibited cell apoptosis. However, knockdown of miR-574 in MCF-7/Adr cells decreased the IC50 and cell growth. Using luciferase assay, SMAD4 was confirmed to be a potential target of miR-574, and the expression of SMAD4 protein was regulated by miR-574. In blood samples of patients, the miR-574 level before chemotherapy was higher than that after chemotherapy.

CONCLUSIONS

We revealed miR-574 could promote doxorubicin resistance of breast cancer MCF-7 cells via down-regulating SMAD4, thus providing a novel target for advancing breast cancer chemotherapy.

Cisplatin suppresses tumor proliferation by inhibiting autophagy in ovarian cancer via long non-coding RNA RP11-135L22.1

OBJECTIVE

To observe the effect of cisplatin-induced autophagy in human ovarian cancer cell lines and explore the correlation between RP11-135L22.1 with cisplatin-induced autophagy.

MATERIALS AND METHODS

Genome-wide expression profile and chemotherapy sensitivity data of ovarian cancer were downloaded from TCGA database. It was found that the expression level of lncRNA RP11-135L22.1 differed between chemotherapy-sensitive group and insensitive group. Besides, RP11-135L22.1 expression levels were detected in 64 ovarian cancer tissues and 30 normal tissues by qRT-PCR. Relationship between RP11-135L22.1 expression levels in 64 ovarian cancer tissues and their clinicopathological characteristics were analyzed by x2-test. Cell viability was detected by CCK8 assay. Cell apoptosis and cell cycle were accessed by flow cytometry. HO8910 cells were selected for transfection of pcDNA-RP11-135L22.1, and qRT-PCR was used to evaluate RP11-135L22.1 expression in cisplatin-treated HO8910 cells. Western blot was performed to analyze the expression changes of autophagy-related proteins.

RESULTS

Genome-wide expression profile of chemotherapy-sensitive and -insensitive patients with ovarian cancer from TCGA database was analyzed by edger package. It was found that RP11-135L22.1 level in chemotherapy-sensitive group was significantly lower than that of insensitive group. QRT-PCR results confirmed that RP11-135L22.1 was lowly expressed in ovarian cancer. The overall survival of patients was positively correlated with the expression of RP11-135L22.1. Furthermore, RP11-135L22.1 was associated with FIGO stage and tumor size. Flow cytometry showed that cisplatin could induce apoptosis and arrest cell cycle in ovarian cancer cells lines. CCK8 assay showed that cisplatin decreased viability of ovarian cancer cells. For in vitro study, HO8910 cells were cultured with medium containing different concentrations of cisplatin or treated with cisplatin for different times. The results revealed that RP11-135L22.1 expression was negatively correlated with the treating time and dose of cisplatin. Western blot showed that cisplatin induced autophagy in ovarian cancer cells in a time- and dose-dependent manner. Cisplatin combined with RP11-135L22.1 can reduce autophagy, increase the apoptosis and inhibit its activity of ovarian cancer cells to a certain extent.

CONCLUSIONS

Cisplatin can induce autophagy in HO8910 ovarian cancer cells. After overexpression of RP11-135L22.1, it inhibited cisplatin-induced autophagy, thus enhancing the effect of cisplatin on ovarian cancer cells.

Ibrutinib presents antitumor activity in skin cancer and induces autophagy

OBJECTIVE

Skin cancer is one of the most common malignancies in dermatology. Patient compliance and prognosis of skin cancer are poor. Ibrutinib, a Bruton's Tyrosine Kinase (BTK) inhibitor, is a new anticancer drug used to treat many cancers. Therefore, we aimed to explore the role of ibrutinib in the treatment of skin cancer.

MATERIALS AND METHODS

Cell Counting Kit-8 (CCK8) and plate cloning assay were used to detect cell proliferation. Apoptosis was determined by flow cytometry. Western blotting analysis was used to analyze the expression of key proteins that regulated autophagy. Proliferation and apoptosis of skin cancer cells and induction of autophagy induced by ibrutinib were evaluated.

RESULTS

CCK8 plate cloning assays showed that ibrutinib can gradually inhibit the skin cancer cell proliferation as the treatment time and dose increased. Results of flow cytometry showed that apoptosis in skin cancer cells were induced after ibrutinib treatment. Western blot showed that autophagy in skin cancer cells was found induced by ibrutinib and also related to the time and concentration of ibrutinib treatment. Combination treatment of ibrutinib and 3MA for skin cancer cells can significantly increase apoptosis.

CONCLUSIONS

Ibrutinib has anti-tumor activity in skin cancer and can induce autophagy. Binding to autophagy inhibitors can promote ibrutinib's anti-skin cancer activity. Our experimental results provided new ideas for developing skin cancer drugs.

Quercetin reduces atherosclerotic lesions by altering the gut microbiota and reducing atherogenic lipid metabolites

AIMS

Epidemiological studies have correlated cardiovascular disease and atherosclerosis with lifestyle factors such as sedentary behaviour and a high-calorie diet. Recent studies of pathogenesis have highlighted the significance of the intestinal microbiota and chronic inflammation with respect to both the onset and development of atherosclerosis. This study examined the hypothesis that the oral administration of quercetin to low-density lipoprotein receptor-null (Ldlr^-/- ) mice would improve gut health by altering the gut microbiota and controlling the levels of atherogenic lipid metabolites and proinflammatory mediators in the intestine and serum.

METHODS AND RESULTS

Mice were maintained on a high-fat diet with or without oral quercetin administration for 12 weeks. Quercetin treatment suppressed body weight gains and reduced the extent of atherosclerotic lesions in the aortic sinus. Reduced malondialdehyde and increased interleukin 6 levels further indicated the protective effect of quercetin against immune/inflammatory responses and oxidative stress. Furthermore, quercetin led to decreased intestinal levels of cholesterol, lysophosphatidic acids and atherogenic lysophosphatidylcholine (LPC 18:1) and an increased level of coprostanol. A phylum-level microbial analysis revealed that quercetin treatment reduced the abundance of Verrocomicrobia and increased microbiome diversity and the abundances of Actinobacteria, Cyanobacteria and Firmicutes. A Spearman analysis revealed negative correlations of Actinobacteria with intestinal and plasma LPC 18:1 and caecal cholesterol levels and of Firmicutes and Cyanobacteria with the plasma LPC 18:1 level.

CONCLUSIONS

This study demonstrated the ability of quercetin treatment to reduce lipid levels, as well as the areas of atherosclerotic lesions and sizes of plaques. This treatment also altered the composition of the gut microbiota and decreased the levels of atherogenic lipid metabolites.

SIGNIFICANCE AND IMPACT OF THE STUDY

Oral quercetin treatment may represent a new approach to mitigating the onset and development of atherosclerosis.

Risk of fracture with dipeptidyl peptidase-4 inhibitors, glucagon-like peptide-1 receptor agonists, or sodium-glucose cotransporter-2 inhibitors in real-world use: systematic review and meta-analysis of observational studies

In the present meta-analysis based on real-world data, the use of dipeptidyl peptidase-4 inhibitors (DPP-4i), glucagon-like peptide-1 receptor agonists (GLP-1ra), or sodium-glucose cotransporter-2 inhibitors (SGLT2i) was not associated with the risk of fracture.

INTRODUCTION

Cumulative evidence from randomized control trials (RCTs) with limited fracture events showed that the use of DPP-4i, GLP-1ra, or SGLT2i may not affect the risk of fracture. However, additional insights from large population-based studies with routinely collected data on fracture events and an adequate amount of fracture events are necessary to draw firm conclusions. To refine and complement the results from RCTs, a systematic review and meta-analysis of observational studies were performed to investigate the association between the use of DPP-4i, GLP-1ra, or SGLT2i and the risk of fracture in real-world settings.

METHODS

The PubMed and Web of Science databases were searched to identify relevant observational studies. A random-effect model was used to estimate the summary relative risks (RRs).

RESULTS

The use of DPP-4i (RR 0.83, 95% CI [confidence interval] 0.60, 1.14; n = 11), GLP-1ra (RR 0.65, 95% CI 0.24, 1.74; n = 4), or SGLT2i (RR 1.02, 95% CI 0.91, 1.16; n = 4) was not associated with the risk of fracture. In general, there was a consistent lack of association between the use of DPP-4i or GLP-1ra and the risk of fracture across nearly all subgroups, except for a significantly reduced risk of hip fracture with the use of GLP-1ra (RR 0.21, 95% CI 0.04, 0.98).

CONCLUSIONS

Cumulative real-world evidence does not support an association between the use of DPP-4i, GLP-1ra, or SGLT2i and the risk of fracture. Our findings, together with the cumulative evidence from RCTs, should reassure policy makers and medical practitioners that the use of these medications is unlikely to increase the risk of fracture among type 2 diabetes mellitus patients in general. Further studies need to investigate the long-term impact of these drugs on the fracture risk, particularly in high-risk populations.

Emergence of ceftazidime/avibactam resistance in carbapenem-resistant Klebsiella pneumoniae in China

OBJECTIVES

The aim was to investigate the activity of ceftazidime/avibactam (CAZ/AVI) against carbapenem-resistant Klebsiella pneumoniae (CRKP) and identify the resistance mechanisms before CAZ/AVI coming to Chinese market.

METHODS

Clinical CRKP isolates were continuously collected from 36 tertiary hospitals in China from 1 March 2017 to 31 July 2017. CAZ/AVI MICs were determined by agar dilution method. CAZ/AVI resistant isolates were submitted to whole genome sequencing. The copy number and relative expression of bla_KPC were determined by quantitative PCR.

RESULTS

A total of 872 CRKP isolates were collected, and MIC₅₀ and MIC₉₀ of CAZ/AVI were 4 and 8 mg/L. The resistant rate of CAZ/AVI was 3.7% (32/872). Among the resistant isolates, 53.1% (17/32) were metallo-β-lactamase-producing K. pneumoniae (MBL-KP), 40.6% (13/32) were Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (KPC-KP) and 6.3% (2/32) produced both MBL and KPC. One of the KPC-KP with high level CAZ/AVI resistance (>128 mg/L) harboured mutated bla_KPC-2 (D179Y). In 12 wild-type bla_KPC-2 isolates, the relative copy number and expression of bla_KPC-2 gene were 2.5-fold and 2.7-fold higher than that in the CAZ/AVI MIC ≤0.5 mg/L group (p < 0.05), and when added avibactam at a fixed concentration of 8 mg/L, 91.7% (11/12) isolates could restore susceptibility.

CONCLUSIONS

Resistance against CAZ/AVI in CRKP emerged before clinical use of CAZ/AVI in China, although most of the CRKP isolates maintained the susceptibility. MBL production, bla_KPC-2 point mutation and high KPC expression played an important role in CAZ/AVI resistance.

[Association between weight control and recurrence of atrial fibrillation after catheter ablation in overweight and obese patients]

Objectives: This study explored the relationship between weight control and atrial fibrillation (AF) recurrence after catheter ablation in overweight and obese patients. Methods: We prospectively enrolled consecutive 333 overweight and obese patients aged 28 to 87 years old, who underwent catheter ablation for AF in Beijing Anzhen Hospital between October 2015 and February 2016. Data of patients' characteristics, laboratory examination and treatment were collected at baseline. Each patient was followed up at 3, 6 and 12 months after ablation to collect information on weight, AF recurrence, stroke, major bleeding, hospitalization for cardiovascular reasons and death, etc. Patients were divided into weight controlled group (ΔBMI<-1 kg/m(2)) and weight uncontrolled group (ΔBMI≥-1 kg/m(2)), according to the changes in the most recent exposure BMI before AF recurrence in patients with recurrence or the BMI at 12 months' follow-up in patients without recurrence and the BMI at baseline. Multivariate logistic regression was performed to adjust other known risk factors of AF recurrence and to explore the association between weight control and AF recurrence after catheter ablation. Results: There were 54 patients in weight controlled group and 279 patients in weight uncontrolled group. There were no significant differences in age, gender, education level, left atrial size and history of hypertension between the two groups (all P>0.05). The proportion of patients using angiotensin-converting enzyme inhibitors/angiotensin receptor blockers was higher in the weight controlled group (50.0%(27/54) vs. 34.8%(97/279), P=0.034). However, there was no significant difference in the proportion of patients with obesity (33.3% (18/54) vs. 29.7% (83/279)), paroxysmal AF (59.3% (32/54) vs. 56.6% (158/279)) and AF duration less than 5 years (76.9% (40/52) vs. 65.4% (178/272)) between the weight controlled group and the uncontrolled group. During 1-year follow-up after ablation, the recurrence rate of AF was significantly lower in the weight controlled group than that in the weight uncontrolled group (14.8% (8/54) vs. 32.6%(91/279), P=0.009). Multivariable logistic regression analysis shows that weight control is independently associated with a lower postoperative AF recurrence rate (OR=0.40, 95%CI 0.18-0.90, P=0.026). Conclusion: Weight control is strongly associated with a lower AF recurrence rate after catheter ablation in overweight and obese patients.

Comparison of size-resolved hygroscopic growth factors of urban aerosol by different methods in Tianjin during a haze episode

Size-resolved hygroscopic growth factors of urban aerosol during a haze episode were measured using a Humidified Tandem Differential Mobility Analyzer (HTDMA) (g_m(RH)). These factors were also derived from size-resolved particulate chemical composition combined with the κ-Köhler theory (g_κ(RH)) and the thermodynamic model ISORROPIA-II running in forward mode (g_iso-f(RH)) and reverse mode (g_iso-r(RH)), respectively. In terms of agreement among these hygroscopic growth factors, g_κ(RH) matched g_m(RH) best, followed by g_iso-r(RH). In contrast, g_iso-f(RH) demonstrated a poorer agreement with g_m(RH). The good consistency among g_m(RH), g_κ(RH), and g_iso-r(RH) was because they only focus on the physical hygroscopic process, whereas g_iso-f(RH) contains not only the direct influence of relative humidity (RH) on particle size but also the influence of gaseous precursor on the particle chemical composition, which indirectly affects the hygroscopicity of the particles. In this sense, size-resolved g_κ(RH) and g_iso-r(RH) in a wide size range are more adequate to investigate the impact of RH on light scattering and aerosol radiative forcing. At RH = 80%, g_κ(RH) for accumulation mode particles was 1.30-1.45 on polluted days and higher than that on clean days (1.2-1.3). Whereas on both polluted and clean days, g_κ(RH) of ultrafine and coarse mode particles were generally lower than 1.25. The strong hygroscopicity of accumulation mode particles observed on polluted days can deteriorate visibility due to their high extinction efficiency.

Effect of feeding grape seed Proanthocyanidin extract on production performance, metabolic and anti-oxidative status of dairy cattle

ABSTRACT Aims to investigate the effects of grape seed proanthocyanidin extract (GSPE) on production performance, metabolism, and anti-oxidative status of Holstein dairy cattle in early lactation. Forty-eight multiparous Holstein dairy cattle were assigned to four groups (CON, G20, G40 and G80) and supplied with 0, 20, 40, and 80mg GSPE/kg of body weight/day. G20 significantly increased milk yield compared with other groups. Milk protein and non-fat-solids were increased in G20, G40 and G80 groups compared with the control group only at the 7th day during the experiment. No significant difference was observed in milk fat and somatic cell count, nor on parameters of energy metabolism in blood, liver function and kidney function between the four groups. There was no significant difference in glutathione peroxidase, superoxide dismutase, total antioxidant capacity, and hydrogen peroxide between the groups; but the malondialdehyde content of G20 significantly increased at day 14 in comparison with CON, and tended to increase at the 28th day. In conclusion, feeding 20mg GSPE/kg of body weight/day was associated with a significant increase in milk yield without detrimental effects on liver or kidney function and with substantial energy metabolism and antioxidant parameters improvement in early lactation dairy cattle.

Effect of high oxygen pretreatment of whole tuber on anti-browning of fresh-cut potato slices during storage

The surface browning usually occurs on fresh-cut potato during storage. The effect of short-time high oxygen pretreatment on anti-browning of fresh-cut potato slices was investigated. The whole potato tubers were firstly immersed in the oxygen concentration of 21%, 60% and 80% for 20 min. Then, the potatoes were peeled, cut and stored at 4 °C for 8 days. The results showed that the short-time 80% oxygen pretreatment possessed significantly anti-browning effect by retarding the increase of polyphenol oxidase (PPO) activity and the accumulation of malondialdehyde (MDA) content, maintaining the cell integrity. Meanwhile, the 80% oxygen treatment could increase the activities of phenylalanine ammonia lyase (PAL) and peroxidase (POD), and the total phenolic content. Importantly, the 80% oxygen treatment could effectively improve the antioxidant capacity. Overall, all results suggest that the short-time high oxygen pretreatment holds great promise on anti-browning of fresh-cut potato.