Thermodynamics-Kinetics-Balanced Metal-Organic Framework for In-Depth Radon Removal under Ambient Conditions.

Radon (Rn), a ubiquitous radioactive noble gas, is the main source of natural radiation to human and one of the major culprits for lung cancer. Reducing ambient Rn concentration by porous materials is considered as the most feasible and energy-saving option to lower this risk, but the in-depth Rn removal under ambient conditions remains an unresolved challenge, mainly due to the weak van der Waals (vdW) interaction between inert Rn and adsorbents and the extremely low partial pressure (<1.8 × 10-14 bar, <106 Bq/m3) of Rn in air. Adsorbents having either favorable adsorption thermodynamics or feasible diffusion kinetics perform poorly in in-depth Rn removal. Herein, we report the discovery of a metal-organic framework (ZIF-7-Im) for efficient Rn capture guided by computational screening and modeling. The size-matched pores in ZIF-7-Im abide by the thermodynamically favorable principle and the exquisitely engineered quasi-open apertures allow for feasible kinetics with little sacrifice of sorption thermodynamics. The as-prepared material can reduce the Rn concentration from hazardous levels to that below the detection limit of the Rn detector under ambient conditions, with an improvement of at least two orders of amplitude on the removal depth compared to the currently best-performing and only commercialized material activated charcoal.

Noninvasive electrocardiography monitoring for very early recurrence predicts long-term outcome in patients after atrial fibrillation ablation.

BACKGROUND: Atrial fibrillation (AF) is the most common sustained arrhythmia, and catheter ablation has been shown to be a highly effective treatment for patients with symptomatic AF. Very early recurrence (VER) of AF within 7 days after catheter ablation is common, but the clinical significance of VER remains unclear. We have examined the usefulness of the noninvasive electrocardiography monitor for the detection of VER and the relationship between VER and late recurrence (LR). METHODS: Eighty-eight patients with paroxysmal or persistent atrial fibrillation were retrospectively included. All patients underwent primary catheter ablation at a large general hospital between March 2016 and August 2018. All patients were followed up in atrial fibrillation clinic at an interval of every 3 months for late recurrence of AF. VER was evaluated by one-lead continuous noninvasive electrocardiography monitoring device for 7 days after ablation. The association between VER and LR was analyzed by univariate and multivariate Cox regression model. RESULTS: Mean age was 62.9 ± 9.7 years, and 39.8% were female. Thirty-two patients (36.4%) experienced VER. After a mean follow-up of 539.36 ± 211.66 days, 17 patients (19.3%) experienced LR. Multivariate Cox regression analysis revealed VER was an independent predictor of LR: HR 3.6 (95% CI, 1.2-10.8), p = .020. In addition, diabetes was also associated with LR of atrial fibrillation. CONCLUSIONS: Noninvasive electrocardiography monitoring was a useful tool for detecting VER and VER after catheter ablation was associated with LR.

Alteration of oncogenic IGF-II gene methylation status associates with hepatocyte malignant transformation.

BACKGROUND: Oncogenic insulin-like growth factor-II (IGF-II) is overexpressed in hepatocellular carcinoma (HCC). The present study aimed to analyze the dynamic alteration of IGF-II CpG site methylation status and its molecular mechanism in HCC progression. METHODS: IGF-II alterations were observed in rat hepatocarcinogenesis models induced by 2-acetylaminofluorene. Liver IGF-II expression was compared by immunohistochemistry or tissue IGF-II specific concentration (nmol/mg protein). Status of human IGF-II promoter 3 (P3) or rat IGF-II P2 CpG site methylation was amplified by methylation-specific polymerase chain reaction (MSP). Serum IGF-II levels were quantitatively detected by an enzyme-linked immunosorbent assay. RESULTS: The levels of hepatic IGF-II expression were significantly elevated in the HCC group (P < 0.001). The unmethylation rate of IGF-II P3 CpG sites was 100% in the HCC-, 52.5% in the paracancerous-, and none (0%) in the distal noncancerous-tissues. Abnormal IGF-II expression was related to differentiation degree, tumor invasion, and positive HBV-DNA (all P < 0.001), with a negative correlation between P3 methylation degree and IGF-II expression. There was a positive correlation between liver IGF-II specific concentration and circulating IGF-II level (r = 0.97, P < 0.001). Significantly negative correlation was found between IGF-II P2 CpG site methylation and circulating IGF-II (rs = -0.89, P < 0.001) or liver IGF-II level (rs = -0.84, P < 0.001). CONCLUSIONS: The increase of serum IGF-II and the alteration of oncogenic gene IGF-II methylation may be biomarkers for HCC diagnosis and DNA methylation may be the therapeutic target of HCC.

Discovering the Relative Efficacy of Inhaled Medications for Chronic Obstructive Pulmonary Disease: Multiple Treatment Comparisons.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is managed by three major classes of inhaled medications: inhaled corticosteroids (ICS), long-acting Beta 2-agonist (LABA), long-acting muscarinic antagonist (LAMA). Single inhaled medication is usually replaced by combined inhaled medications for efficacy enhancement. However, this practice should be supported by clinical evidence for large-scale implementations. METHODS: The relative efficacy of inhaled medications is determined by three endpoints: changes in the trough forced expiratory volume in 1 second (tFEV1), changes in the St George's Respiratory Questionnaire (SGRQ) score and the proportion of SGRQ responders which represents a reduction in SGRQ total score at week 24 of ≥4.0. A total of 76 eligible studies were identified in PubMed and Embase. Relevant data were extracted for the purpose of evidence synthesis. Then, raw mean differences (MD) and odds ratios (ORs) were produced by using the network meta-analysis. RESULTS: Patients with ICS + LABA, ICS + LABA + LAMA, LABA, LABA + LAMA, LAMA exhibited significant increases in the tFEV1 compared to those with placebo (P < 0.05). Moreover, patients with ICS + LABA + LAMA exhibited the largest increase in the average tFEV1 and the largest decrease in the average SGRQ scores compared to those with placebo. COPD patients with ICS + LABA + LAMA were far more likely to achieve a significant reduction in the SGRQ scores compared to those with placebo or other inhaled medications (OR > 1). CONCLUSIONS: The combined inhaled medication of ICS + LABA + LAMA may be more efficacious than other inhaled medications for COPD patients.

Tailoring lanthanide doping in perovskite CaTiO3 for luminescence applications.

Perovskite oxide materials have been attracting significant attention due to their rich physical and chemical properties. With its proven stability and bio-compatibility, we suggest the lanthanide-doped perovskite to be a promising material for biological luminescence applications. Here, taking CaTiO3 as a concrete example, we systematically investigate its doping properties using first-principles computational methods. We determine the conditions allowing the growth of CaTiO3 against various competing phases. We obtain the formation energies of various intrinsic point defects in the material. The doping configuration and the charge state of the lanthanide dopants are determined. We find that for heavier elements in the lanthanide family, the substitution at the Ca site is favored under p-type growth conditions and tends to be trivalent, whereas the substitution at the Ti site is favored under n-type growth conditions and tends to be divalent. And for lighter elements in the family, the substitution at the Ca site is more favored for most cases and the dopant is more likely to be trivalent. By tuning the growth conditions, one could control the valence state of the lanthanide dopant, which in turn controls the luminescence spectra. We collect and identify the emission peaks in the infrared biological window, based on which possible doping schemes are suggested for bio-labeling and imaging applications.

[Plankton Community Stability and Drive Factor Identification Guizhou Plateau Reservoir].

In order to understand the stability of the zooplankton and phytoplankton communities in the Guizhou plateau reservoir environment, the process of reservoir water quality change affecting the stability of plankton was studied. The changes in the plankton community and water quality in three different nutrient reservoirs （Huaxi Reservoir, Goupitan Reservoir, and Hailong Reservoir） were studied from October 2020 to August 2021. The stability of the zooplankton and phytoplankton communities was studied using time-lag analysis （TLA）. Variance decomposition analysis （VPA） was used to explore the response of the two communities to environmental changes. The driving factors of plankton community changes in reservoirs were also revealed. The results showed that Huaxi Reservoir and Goupitan Reservoir were mesotrophic reservoirs, and Hailong Reservoir was a eutrophic reservoir. The average comprehensive nutrition indices of the three reservoirs were 44.07, 44.68, and 50.25. A total of 51 species of zooplankton rotifers, 39 species of rotifers, three species of copepods, and nine species of cladocera were identified. Among them, the abundance of rotifers was the highest, accounting for 85.96%. A total of seven phyla and 73 species of phytoplankton were identified, including 16 species in the phylum Cyanophyta, 32 species in the phylum Chlorophyta, 16 species in the phylum Diatoma, three species in the phylum Chlorophyta, four species in the phylum Euglenophyta, and one species each in the phyla Cryptophyta and Chrysophyta. Among them, the abundance of cyanobacteria and diatoms was the highest, accounting for 66.2% and 27.35%, respectively. The median absolute deviation （MAD） of the Bray-Curtis distance of zooplankton and phytoplankton community in the three reservoirs were 0.67 and 0.65 in Huaxi Reservoir, 0.80 and 0.69 in Goupitan Reservoir, and 0.85 and 0.47 in Hailong Reservoir, respectively. The larger the value, the greater the variation in the community. The absolute value of the slope of zooplankton was greater than that of phytoplankton in the TLA results, and the absolute values of the slopes were 0.018 and 0.004, respectively. The larger the absolute value of the slope, the faster the community variability. The zooplankton community in the three reservoirs was less stable than the phytoplankton community and more sensitive to environmental changes, and the degree of variation was greater. The higher the degree of eutrophication of the reservoir, the more obvious this phenomenon. VPA showed that the changes in plankton communities in Huaxi Reservoir and Hailong Reservoir were mainly influenced by water temperature and eutrophication factors. The changes in planktonic community in Goupitan Reservoir were mainly influenced by water temperature and chemical factors. The driving factors of Huaxi Reservoir were water temperature, TP, permanganate index, and SD. The driving factors of Goupitan Reservoir were water temperature, NO3-- N, and pH. The driving factors of Hailong Reservoir were water temperature and TP. Nutrients and water temperature were the main factors affecting the stability of plankton communities in reservoirs.

Impact of social support on college students' anxiety due to COVID-19 isolation: Mediating roles of perceived risk and resilience in the postpandemic period.

Introduction: Because of the outbreak of COVID-19, several colleges and universities in Xi'an, China, implemented quarantine measures and closed their gates, which increased anxiety among the students. Methods: The Perceived Social Support Scale, Perceived Risk of COVID-19 Pandemic Scale, Connor-Davidson Resilience Scale, and Self-Rating Anxiety Scale were used for measurements. SPSS26 and AMOS26 (IBM SPSS AMOS Statistics, New York, United States) were used for data analysis. Structural equation modeling (SEM) was used to test the data from the 2,251 respondents and the hypothetical model. Results: The students' perceived social support was discovered to have had a significant negative effect on anxiety. The students' perceived COVID-19 risk and resilience played significant mediating roles in the relationship between social support and anxiety. Discussion: When college students feel social support and have resilience, they can reduce anxiety during the epidemic stage. Therefore, education administrators and parents should help college students to identify the current situation of the epidemic environment, enrich relevant knowledge.

Multiomic Analysis Reveals Core Regulatory Mechanisms underlying Steroidal Glycoalkaloid Metabolism in Potato Tubers.

Steroidal glycoalkaloids (SGAs) present in germinated potato tubers are toxic; however, the mechanisms underlying SGA metabolism are poorly understood. Therefore, integrated transcriptome, metabolome, and hormone analyses were performed in this study to identify and characterize the key regulatory genes, metabolites, and phytohormones related to glycoalkaloid regulation. Based on transcriptome sequencing of bud eyes of germinated and dormant potato tubers, a total of 6260 differentially expressed genes were identified, which were mainly responsible for phytohormone signal transduction, carbohydrate metabolism, and secondary metabolite biosynthesis. Two TCP14 genes were identified as the core transcription factors that potentially regulate SGA synthesis. Metabolite analysis indicated that 149 significantly different metabolites were detected, and they were enriched in metabolic and biosynthetic pathways of secondary metabolites. In these pathways, the α-solanine content was increased and the expression of genes related to glycoalkaloid biosynthesis was upregulated. Levels of gibberellin and jasmonic acid were increased, whereas that of abscisic acid was decreased. This study lays a foundation for investigating the biosynthesis and regulation of SGAs and provides the reference for the production and consumption of potato tubers.

Identification and Expression Profiles of Putative Soluble Chemoreception Proteins from Lasioderma serricorne (Coleoptera: Anobiidae) Antennal Transcriptome.

The cigarette beetle, Lasioderma serricorne (Fabricius) (Coleoptera: Anobiidae), is a destructive stored product pest worldwide. Adult cigarette beetles are known to rely on host volatiles and pheromones to locate suitable habitats for oviposition and mating, respectively. However, little is known about the chemosensory mechanisms of these pests. Soluble chemoreception proteins are believed to initiate olfactory signal transduction in insects, which play important roles in host searching and mating behaviors. In this study, we sequenced the antennal transcriptome of L. serricorne and identified 14 odorant-binding proteins (OBPs), 5 chemosensory proteins (CSPs), and 2 Niemann-Pick C2 proteins (NPC2). Quantitative realtime PCR (qPCR) results revealed that several genes (LserOBP2, 3, 6, and 14) were predominantly expressed in females, which might be involved in specific functions in this gender. The five LserOBPs (LserOBP1, 4, 8, 10, and 12) that were highly expressed in the male antennae might encode proteins involved in specific functions in males. These findings will contribute to a better understanding of the olfactory system in this stored product pest and will assist in the development of efficient and environmentally friendly strategies for controlling L. serricorne.

[Value of cardiac magnetic resonance imaging for the diagnosis of cardiac amyloidosis].

OBJECTIVE: To observe the clinical features and cardiac magnetic resonance imaging (CMR) characteristics of patients with endomyocardial biopsy (EMB)-proven cardiac amyloidosis (CA). METHODS: EMB proven CA patients underwent CMR examination from September 2006 to December 2010 were included. The findings of clinical manifestation, electrocardiogram, echocardiography and CMR were analyzed. RESULTS: Among the 18 patients with EMB verified CA, 5 patients underwent CMR. All 5 patients had heart failure symptoms and electrocardiogram was abnormal. Echocardiogram showed concentric left ventricular hypertrophy, granular appearance of the myocardium, left atrial enlargement and moderate to severe left ventricular diastolic dysfunction. CMR revealed increased thickness of the left ventricular wall (especially at the inter-ventricular septum), enlarged bilateral auricle, restricted left ventricular filling with normal or mild to moderate reduced systolic function. Pleural and pericardial effusions were observed in 2 patients. Abnormal late gadolinium enhancement (LGE) was detected in all 5 patients. CMR revealed different patterns of LGE. Left ventricular global subendocardial delayed gadolinium enhancement or transmural delayed gadolinium enhancement were found, and patients also showed line-, granular- or patchy-like enhancement. The degree and range of LGE paralleled the disease course and were consistent with electrocardiogram changes. CONCLUSIONS: As a noninvasive diagnostic tool, CMR is valuable in the diagnosis of CA. For patients with clinical suspicion of CA, CMR could be a helpful diagnostic tool, especially in the hospitals where EMB is not available.

[Expression characteristics of hypoxia inducible factor-1a and its clinical values in hepatocellular carcinoma].

OBJECTIVE: To investigate the dynamic expression of hypoxia inducible factor-1alpha (HIF-1alpha) and its clinical values in hepatocellular carcinoma (HCC). METHODS: The dynamic changes of liver pathology, HIF-1alpha transcription and expression were observed through the hepatoma model. The self-control specimens from 35 human HCC patients were collected and the expression, cellular distribution, and clinicopathological features of HIF-1alpha and its gene was analyzed by immunohistochemistry, western blotting and nested- PCR, respectively. RESULTS: Both levels of hepatic HIF-1alpha and HIF-1alpha mRNA expression increased during the HCC development course. The incidence of HIF-1alpha and the ratio of HIF-1alpha to beta-actin was 0% and 0.16+/-0.02 in the control rats, 77.8% and 0.29+/-0.04 in the denatured rats, 88.9% and 0.52+/-0.03 in the precancerous rats, and 100% and 0.84+/-0.02 in the cancerous rats respectively, with significant difference between the control group and any of the experimental groups (P = 0.000). The positive HIF-1alpha was brown and granule-like and mainly presented in cytoplasm and few in nucleus. The incidence of HIF-1alpha was 80% (28/35) in HCC and 100% (35/35) in its surrounding tissues. The clinical pathological features indicated HIF-1alpha expression associated with tumor size and differentiation degree the of HCC. No correlation was found between HIF-1alpha and tumor numbers or positive-HBsAg. CONCLUSIONS: HIF-1alpha expression is associated with occurrence and development of HCC, and is perhaps a target molecule for HCC therapy.

[Studies on the spectrum of tea seed oily properties].

The fatty acid composition of pu'er tea seed oil from Simao region was determined by gas chromatography. It was found that the quality fraction of oleic acid in pu'er tea seed oil is higher than in peanut oil and rapeseed oil, and lower than in camellia seed oil and olive oil, and the quality fraction of erucic acid in Pu'er tea seed oil is lower than in peanut oil, rapeseed oil and camellia seed oil, while slightly higher than in olive oil. Therefore, pu'er fruit tea is an ideal oil resource. At the same time 30 kinds of volatile compounds in pu'er tea seed oil were identified by gas-chromatography-mass spectrometry. They are mostly alcohols, aldehydes, ketones and esters, and most of these compounds contain unsaturated bond. The relatively domestic reports are rare.

[Electrocardiographic and echocardiographic features of patients with primary cardiac amyloidosis].

OBJECTIVE: To summarize the electrocardiography and echocardiography features of patients with cardiac amyloidosis (CA) diagnosed by endo-myocardial biopsy (EMB). METHODS: A total of 20 consecutive patients [7 men, mean age (50 ± 12) years] referred for EMB because of clinical suspicion of CA from September 2006 to October 2009 were included in the study. Primary CA was diagnosed in 11 out of 20 patients (55%) by EMB and biomarkers examination. The electrocardiography and echocardiography features were analyzed. RESULTS: The voltage of all the limb leads were low in the 11 CA patients [mean values of (0.33 - 0.51) mV], the incidence of low voltage and pseudo-infarction patterns were 45% and 45%, respectively. Concentric hypertrophy and normal left ventricular diameters were evidenced in all CA patients on echocardiography, left atrial enlargement (n = 10, 91%), granular/sparking appearance of the myocardium (n = 9, 82%) and moderate to large pericardial effusion (n = 7, 64%) as well as left ventricular systolic dysfunction (n = 8, 73%) were often presented in CA patients. CONCLUSIONS: The diagnosis of primary CA should be considered in patients with unknown origin of heart failure, concentric hypertrophy and normal left ventricular diameters with granular/sparking appearance of the myocardium or pericardial effusion presented on echocardiography and low voltage of limb leads or pseudo-infarction pattern presented on electrocardiography. EMB and serum (urine) biomarkers examinations should be then performed to confirm or exclude the diagnosis of CA.

[Comparison of adenosine versus iloprost by acute vasodilator test in patients of pulmonary arterial hypertension complicated with connective tissue diseases].

OBJECTIVE: To compare the acute hemodynamic effects of adenosine versus iloprost in patients of pulmonary arterial hypertension (PAH) complicated with connective tissue diseases. METHODS: During right heart catheterization, 18 patients of PAH complicated with connective tissue diseases sequentially received intravenous infusion of adenosine and inhaled iloprost. After the baseline hemodynamic data were obtained, an adenosine infusion was started and titrated to the maximal tolerated dose. The hemodynamic parameters were allowed to return to baseline. Then inhalation of iloprost was administered. The effects of both medicines on the patient's hemodynamics were monitored. RESULTS: As compared with the baseline values, the systolic pulmonary artery pressure and pulmonary vascular resistance significantly decreased [(71 +/- 30) vs (80 +/- 29) mm Hg and (712 +/- 440) vs (824 +/- 464) dyn x s x cm(-5) respectively, both P < 0.05) while the heart rate increased significantly [(93 +/- 17) vs (83 +/-16) beat/min, P < 0.05] in the adenosine group. Inhaled iloprost could also lower the systolic pulmonary artery pressure [(66 +/- 29) vs (79 +/- 28) mm Hg, P < 0.05], mean pulmonary artery pressure [(43 +/- 19) vs (52 +/- 19) mm Hg, P < 0.05] and pulmonary vascular resistance [(632 +/- 440) vs (816 +/- 448) dyn x s x cm(-5), P < 0.05] without any effect upon heart rate. Inhaled iloprost exerted more potent effect on lowering mean pulmonary artery pressure and pulmonary vascular resistance than adenosine (P < 0.05). The two medicines did not affect cardiac output, pulse oxygen saturation or systemic blood pressure. The side effects were fewer in the iloprost inhalation group than the adenosine group. CONCLUSION: During acute vasodilator testing, inhaled iloprost was more potent than infused adenosine as a pulmonary vasodilator in PAH complicated with connective tissue diseases.

Dynamic expression of rat heat shock protein gp96 and its gene during development of hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is characterized by multicause, obvious multistage and multifocal processes of tumor progression. The development of HCC is related intimately to overexpression and signal transduction of many cellular factors. This study was undertaken to investigate the dynamic expression and alteration of heat shock protein (HSP) gp96 along with its gene during HCC development. METHODS: A rat model of hepatoma induced with 2-fluorenylacetamide (2-FAA, 0.05%) was established in male Sprague-Dawley rats. Total RNA and pathological changes were observed during hepatocarcinogenesis. Total RNAs were transcribed into cDNA by reverse transcription and the gene fragment of gp96 was amplified by nested RT-PCR. The gp96 expression in rat liver tissues was semi-quantitatively analyzed by immunohistochemistry. RESULTS: Histological examination suggested that hepatocytes in rats fed with 2-FAA showed vacuole-like denaturation at the early stages, then dysplastic nodules appeared at the middle stage, and finally progressed to tubercles of cancerous nests. A tendency of increasing liver gp96 protein level was found from normal liver to precancerous to cancerous tissues during hepatoma development (P<0.01), and was in accordance with the changes in gp96 mRNA (P<0.05). CONCLUSION: HSP gp96 is involved in HCC development and its overexpression may be a useful marker for early diagnosis.

[Risk factors for coronary artery disease stimulate urokinase receptor expression on monocytes].

OBJECTIVE: To evaluate the effect of risk factors for coronary artery disease (CAD) on urokinase receptor (uPAR) expression on monocytes. METHODS: A total of 106 patients were enrolled and divided into five risk-factor groups: sixteen with hypertension, twenty-four with dyslipidemia, eighteen with hypertension + obesity, eighteen with dyslipidemia + obesity and thirty with hypertension + dyslipidemia + obesity. Seventeen healthy volunteers were recruited as control group. Monocyte expression of uPAR and mean fluorescence intensity index (MFI Index) of uPAR were measured by flow cytometer (FACSCalibur). RESULTS: No difference in monocyte uPAR expression was detected between hypertension and control group [(4.9 +/- 12.5)% vs. (7.7 +/- 10.3)%, P=0.74]. However, the uPAR expression was raised to (23.7 +/- 22.5)% in hyperlipidemia group, a 3.9- and a 2.1-fold increase compared with those in hypertension (P<0.01) and control group (P<0.05), respectively. When combined with obesity, uPAR expression was elevated further to (32.9 +/- 30.8)% in hypertension + obesity group, (37.4 +/- 31.4)% in dyslipidemia + obesity group and (23.8 +/- 20.5)% in hypertension + dyslipidemia + obesity group, all having statistical significance compared with control group or hypertension group (P<0.01). The results were the same when corrected by age, BMI and hs-CRP. uPAR MFI Index was increased from 0.78 +/- 0.86 in control group to 1.91 +/- 1.97 and 3.33 +/- 2.52 in dyslipidemia group and hypertension + obesity group, respectively, P<0.05. Linear regression analysis revealed a significant correlation between uPAR expression and FBG concentration in dyslipidemia group, r=0.72, P=0.04. CONCLUSIONS: uPAR expression was elevated on monocytes in patients with risk factors for CAD. Dyslipidemia and obesity may contribute to the increase of uPAR expression.

Prevention of sudden cardiac death in patients with ejection fraction reduced heart failure receiving ICD implantation / 中国实用内科杂志

OBJECTIVE: By recording the treatment events of implantable cardioverter defibrillator(ICD) in patients with ejection fraction reduced heart failure(HFrEF), to analyze the difference in primary and secondary prevention patients. METHODS: A single center retrospective study was conducted. HFrEF patients with ICD or cardiac resynchronization therapy with cardioverter defibrillator(CRT-D) implanted in Peking Union Medical College Hospital from January 2006 to December 2017 were enrolled in our study. Basic clinical data was collected and ICD treatment events were recorded during follow-up. The appropriate treatment events were identified according to electrocardiogram recorded by ICD. The ICD treatment events of primary and secondary prevention patients were analyzed. RESULTS: 1) A total of 145 patients with HFrEF implanted with ICD or CRT-D were enrolled, 103 primary prevention patients and 42 secondary prevention patients. Primary prevention patients had longer left ventricular end-systolic diameter(LVESD) and lower left ventricular ejection fraction(LVEF) than secondary prevention patients. 2) Multivariate competitive risk regression analysis showed that secondary prevention patients and male patients had higher risk of receiving appropriate treatment and appropriate shock therapy. 3) K-M curve and Log-Rank test showed that there was no significant difference in the risk of inappropriate treatment between primary and secondary prevention patients. The main cause of inappropriate treatment was atrial flutter or atrial fibrillation. CONCLUSION: 1) Primary prevention patients have lower risk of receiving appropriate treatment and appropriate shock therapy than secondary prevention patients; 2) There is no significant difference between primary and secondary prevention patients in the risk of inappropriate treatment. The main cause of inappropriate treatment events is atrial flutter or atrial fibrillation.

Ventricular arrhythmias originating from left ventricle posterior papillary muscle:electrocardiographic characteristics and catheter ablation / 中国介入心脏病学杂志

Objective To investigate the clinical characteristics, electrocardiography, electrophysiological features and the eff ectiveness of catheter ablation of ventricular arrhythmias originating from left ventricle posterior papillary muscles. Methods Clinical features and electrocardiography of 16 patients with ventricular arrhythmias arising from left ventricular posterior papillary muscles underwent catheter ablation were retrospectively analyzed. Activation mapping and/or pace mapping were performed to identify the site of origin and transthoracic echocardiography were used to demonstrate ablation catheter position and contact. The immediate success and recurrence rates were evaluated. Results During arrhythmias, QRS wave duration of 16 patients [5 men, mean age (45.0±18.2) years] was (155.1±9.0)ms. The prevalence of R>r' and r<R' of V1QRS morphology was 6/16 and 9/16, respectively. Earliest local ventricular electrogram preceded QRS wave by (30.8±8.4)ms at successful ablation site. Immediate success were achieved in 14 patients (14/16) ,11 patients(11/16) had full clinical follow-up and recurrences occurred in 5 patients (5/11). Conclusions Electrocardiography of ventricular arrhythmias originating from left ventricular posterior papillary muscles has its specifi c features. Earliest focal electrogram indicates successful ablation site and transthoracic echocardiography can demonstrate ablation catheter position and increase success rate but recurrence rate is still high.

Hemodynamic parameters obtained by transthoracic echocardiography and right heart catheterization: a comparative study in patients with pulmonary hypertension.

BACKGROUND: Hemodynamic evaluation is crucial for the management of patients with pulmonary hypertention. Clinicians often prefer a rapid and non-invasive method. This study aimed to examine the feasibility of transthoracic echocardiography for the measurements of hemodynamic parameters in patients with pulmonary hypertension. METHODS: A prospective single-center study was conducted among 42 patients with pulmonary hypertension caused by different diseases. Transthoracic echocardiography and right-heart catheterization were performed within 24 hours. Pulmonary artery systolic, diastolic and mean pressure (PASP, PADP and PAMP), cardiac output (CO), and pulmonary capillary wedge pressure (PCWP) were measured by both methods. A linear correlation and a Bland-Altman analysis were performed to compare the two groups of hemodynamic parameters. RESULTS: A good correlation was found between invasive and non-invasive measurements for PASP (r = 0.96), PADP (r = 0.85), PAMP (r = 0.88), CO (r = 0.82), and PCWP (r = 0.81). Further agreement analysis done by the Bland-Altman method showed that bias and a 95% confidence interval for PASP, PADP, and CO were clinically acceptable while great discrepancies existed for PAMP and PCWP. CONCLUSIONS: The non-invasive measurements by PASP, PADP, and CO in patients with pulmonary hypertension correlate well with the invasive determinations. Transthoracic echocardiography (TTE) was inappropriate for estimating PCWP and PAMP.

Formation and instability of silver nanofilament in Ag-based programmable metallization cells.

In this paper, we report on the formation and rupture of Ag nanofilament on planar Ag/TiO2/Pt cells using visual observation. During the forming process, the filament tends to stay very thin. Specifically, it is so thin that it breaks up into a chain of nanospheres (according to Rayleigh instability) right after the formation has been completed. Similar mechanical breakup may also impact vertically stacked cells, causing reliability concerns.