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1.
Nature ; 592(7852): 105-109, 2021 04.
Article in English | MEDLINE | ID: mdl-33692546

ABSTRACT

The plant immune system is fundamental for plant survival in natural ecosystems and for productivity in crop fields. Substantial evidence supports the prevailing notion that plants possess a two-tiered innate immune system, called pattern-triggered immunity (PTI) and effector-triggered immunity (ETI). PTI is triggered by microbial patterns via cell surface-localized pattern-recognition receptors (PRRs), whereas ETI is activated by pathogen effector proteins via predominantly intracellularly localized receptors called nucleotide-binding, leucine-rich repeat receptors (NLRs)1-4. PTI and ETI are initiated by distinct activation mechanisms and involve different early signalling cascades5,6. Here we show that Arabidopsis PRR and PRR co-receptor mutants-fls2 efr cerk1 and bak1 bkk1 cerk1 triple mutants-are markedly impaired in ETI responses when challenged with incompatible Pseudomonas syrinage bacteria. We further show that the production of reactive oxygen species by the NADPH oxidase RBOHD is a critical early signalling event connecting PRR- and NLR-mediated immunity, and that the receptor-like cytoplasmic kinase BIK1 is necessary for full activation of RBOHD, gene expression and bacterial resistance during ETI. Moreover, NLR signalling rapidly augments the transcript and/or protein levels of key PTI components. Our study supports a revised model in which potentiation of PTI is an indispensable component of ETI during bacterial infection. This revised model conceptually unites two major immune signalling cascades in plants and mechanistically explains some of the long-observed similarities in downstream defence outputs between PTI and ETI.


Subject(s)
Arabidopsis/immunology , NLR Proteins/immunology , Plant Immunity/immunology , Receptors, Pattern Recognition/immunology , Arabidopsis/genetics , Arabidopsis/microbiology , Arabidopsis Proteins/metabolism , NADPH Oxidases/metabolism , Plant Diseases/genetics , Plant Diseases/immunology , Plant Diseases/microbiology , Protein Serine-Threonine Kinases/metabolism , Pseudomonas syringae/immunology , Reactive Oxygen Species/metabolism , Signal Transduction/immunology
2.
Plant Physiol ; 193(1): 792-808, 2023 08 31.
Article in English | MEDLINE | ID: mdl-37300539

ABSTRACT

The apoplast of plant leaves, the intercellular space between mesophyll cells, is normally largely filled with air with a minimal amount of liquid water in it, which is essential for key physiological processes such as gas exchange to occur. Phytopathogens exploit virulence factors to induce a water-rich environment, or "water-soaked" area, in the apoplast of the infected leaf tissue to promote disease. We propose that plants evolved a "water soaking" pathway, which normally keeps a nonflooded leaf apoplast for plant growth but is disturbed by microbial pathogens to facilitate infection. Investigation of the "water soaking" pathway and leaf water control mechanisms is a fundamental, yet previously overlooked, aspect of plant physiology. To identify key components in the "water soaking" pathway, we performed a genetic screen to isolate Arabidopsis (Arabidopsis thaliana) severe water soaking (sws) mutants that show liquid water overaccumulation in the leaf under high air humidity, a condition required for visible water soaking. Here, we report the sws1 mutant, which displays rapid water soaking upon high humidity treatment due to a loss-of-function mutation in CURLY LEAF (CLF), encoding a histone methyltransferase in the POLYCOMB REPRESSIVE COMPLEX 2 (PRC2). We found that the sws1 (clf) mutant exhibits enhanced abscisic acid (ABA) levels and stomatal closure, which are indispensable for its water soaking phenotype and mediated by CLF's epigenetic regulation of a group of ABA-associated NAM, ATAF, and CUC (NAC) transcription factor genes, NAC019/055/072. The clf mutant showed weakened immunity, which likely also contributes to the water soaking phenotype. In addition, the clf plant supports a substantially higher level of Pseudomonas syringae pathogen-induced water soaking and bacterial multiplication, in an ABA pathway and NAC019/055/072-dependent manner. Collectively, our study sheds light on an important question in plant biology and demonstrates CLF as a key modulator of leaf liquid water status via epigenetic regulation of the ABA pathway and stomatal movement.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis/metabolism , Water/metabolism , Epigenesis, Genetic , Abscisic Acid/pharmacology , Abscisic Acid/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Plant Leaves/genetics , Plant Leaves/metabolism , Plant Stomata/metabolism , Homeodomain Proteins/genetics
3.
Int J Obes (Lond) ; 47(5): 399-405, 2023 05.
Article in English | MEDLINE | ID: mdl-36899038

ABSTRACT

BACKGROUND: Obesity is major cause of cardiovascular diseases. Metabolically healthy obesity (MHO) may increase heart failure risk early in life, and may be reflected in impaired cardiac structure and function. Therefore, we aimed to examine the relationship between MHO in young adulthood and cardiac structure and function. METHODS: A total of 3066 participants from the Coronary Artery Risk Development in Young Adults (CARDIA) study were included, who completed echocardiography in young adulthood and middle age. The participants were grouped by obesity status (body mass index ≥30 kg/m2) and poor metabolic health (≥2 criteria for metabolic syndrome) into four metabolic phenotypes as follows: metabolically healthy non-obesity (MHN), MHO, metabolically unhealthy non-obesity (MUN), metabolically unhealthy obesity (MUO). The associations of the metabolic phenotypes (MHN serving as the reference) with left ventricular (LV) structure and function were evaluated using multiple linear regression models. RESULTS: At baseline, mean age was 25 years, 56.4% were women, and 44.7% were black. After a follow-up 25 years, MUN in young adulthood was associated with worse LV diastolic function (E/é ratio, ß [95% CI], 0.73 [0.18, 1.28]), worse systolic function (global longitudinal strain [GLS], 0.60 [0.08, 1.12]) in comparison with MHN. MHO and MUO were associated with LV hypertrophy (LV mass index, 7.49 g/m2 [4.63, 10.35]; 18.23 g/m2 [12.47, 23.99], respectively), worse diastolic function (E/é ratio, 0.67 [0.31, 1.02]; 1.47 [0.79, 2.14], respectively), and worse systolic function (GLS, 0.72 [0.38, 1.06]; 1.35 [0.64, 2.05], respectively) in comparison with MHN. These results were consistent in several sensitivity analyses. CONCLUSIONS: In this community-based cohort using data from the CARDIA study, obesity in young adulthood was significantly associated with LV hypertrophy, worse systolic and diastolic function regardless of metabolic status. Relationship of Baseline Metabolic Phenotypes with Young Adulthood and Midlife Cardiac Structure and Function. Adjusted for year 0 covariates: age, sex, race, educational level, smoking status, drinking status, and physical activity; metabolically healthy non-obesity was used as a reference category for comparison. † Criteria for metabolic syndrome are listed in Supplementary Table S6. MUN metabolically unhealthy non-obesity, MHO metabolically healthy obesity, LVMi left ventricular mass index, LVEF left ventricular ejection fraction, E/A early to late peak diastolic mitral flow velocity ratio, E/é mitral inflow velocity to early diastolic mitral annular velocity, CI confidence interval.


Subject(s)
Metabolic Syndrome , Obesity, Metabolically Benign , Female , Male , Humans , Ventricular Function, Left , Stroke Volume , Metabolic Syndrome/epidemiology , Metabolic Syndrome/complications , Risk Factors , Obesity/complications , Obesity/epidemiology , Hypertrophy, Left Ventricular , Body Mass Index , Phenotype
4.
Cardiovasc Diabetol ; 22(1): 238, 2023 09 02.
Article in English | MEDLINE | ID: mdl-37660027

ABSTRACT

BACKGROUND: The triglyceride-glucose (TyG) index is a reliable surrogate marker of insulin resistance (IR). However, whether the TyG index has prognostic value in patients with moderate to severe aortic stenosis (AS) remains unclear. METHODS: This study enrolled 317 patients with moderate to severe AS at the First Affiliated Hospital of Sun Yat-Sen University. The patients were grouped according to the cut-off value of the TyG index. Cox regression with Firth's penalized maximum likelihood method and restricted cubic splines regression were conducted to assess the association between the TyG index and all-cause mortality. The added value of the TyG index included in the traditional risk factors model for outcome prediction was also analyzed. RESULTS: Among 317 patients (mean age 67.70 years, 62.8% male), there was 84 all-cause mortality during a median 38.07 months follow-up. After fully adjusting for confounders, a per-unit increase in the TyG index was associated with a 62% higher all-cause mortality risk (HR 1.622, 95% CI 1.086-2.416, p = 0.018). The restricted cubic splines regression model revealed a linear association between the TyG index and the risk of all-cause mortality (p for nonlinearity = 0.632). The addition of the TyG index in the basic risk model has an incremental effect on the prediction of mortality [C-statistic change from 0.755 to 0.768; continuous net reclassification improvement (95% CI): 0.299 (0.051-0.546), p = 0.017; integrated discrimination improvement: 0.017 (0.001-0.033), p = 0.044]. CONCLUSIONS: Higher IR assessed by the TyG index was associated with a higher risk of all-cause mortality in patients with moderate and severe AS.


Subject(s)
Aortic Valve Stenosis , Insulin Resistance , Humans , Male , Aged , Female , Retrospective Studies , Glucose , Triglycerides , Aortic Valve Stenosis/diagnostic imaging
5.
Nutr Metab Cardiovasc Dis ; 33(5): 1029-1036, 2023 05.
Article in English | MEDLINE | ID: mdl-36710116

ABSTRACT

BACKGROUND AND AIM: Multiple studies have investigated the association between coronary heart disease (CHD) risk factors and aortic valve stenosis (AS). However, limited studies have explored the relationship between CHD risk scores and AS. Whether incident risk scores for coronary heart disease (CHD-RISK) may be applied to predict AS remains unclear. We aim to investigate the association between AS and CHD-RISK. METHODS AND RESULTS: We included 4791 participants (age 54.6 ± 5.0 yrs, 58.7% women, 81% were of European origin), and CHD-RISK was estimated in 1990-1992. The participants were then followed-up until December 31, 2013. The primary outcome was hemodynamic significant AS identified by Doppler echocardiography in 2011-2013. We used multivariate-logistic regression models to assess the associations between CHD-RISK and AS. During follow-up, 963 (20.1%) cases of AS were identified. Per-standard deviation (6%) increase in CHD-RISK was associated with OR 95% Cl [1.194, 95% CI 1.068 to 1.335, p = 0.002] risk of AS in the fully adjusted models. Results were similar when stratified by quintiles of CHD-RISK, using the lowest quintiles <0.94% of CHD-RISK as the reference, 0.94%-2.26%, 2.26%-4.83%, 4.83%-9.21%, and >9.21% were; 1.33 (95% CI, 0.99-1.78, p = 0.055), 1.64 (95% CI, 1.17-2.29, p = 0.004), 2.23 (95% CI, 1.49-3.32, p = <0.001), 2.66 (95% CI, 1.65-4.31, p = <0.001) respectively. CONCLUSIONS: CHD-RISK was associated with AS. CHD-RISK and AS were high in females, age ≥55 yrs, current smokers, and BMI ≥ 30 kg/m2. This investigation suggests CHD-RISK may be applied to forecast AS risk similar to CHD. Future studies are required to detect, manage, and establish better treatment strategies in these high-risk subgroups.


Subject(s)
Aortic Valve Stenosis , Coronary Disease , Humans , Female , Middle Aged , Male , Coronary Disease/diagnostic imaging , Coronary Disease/epidemiology , Risk Factors , Aortic Valve Stenosis/diagnostic imaging , Aortic Valve Stenosis/epidemiology
6.
Plant Cell Rep ; 42(3): 549-559, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36598573

ABSTRACT

KEY MESSAGE: Arabidopsis nucleoporin involved in the regulation of ethylene signaling via controlling of nucleocytoplasmic transport of mRNAs. The two-way transport of mRNAs between the nucleus and cytoplasm are controlled by the nuclear pore complex (NPC). In higher plants, the NPC contains at least 30 nucleoporins. The Arabidopsis nucleoporins are involved in various biological processes such as pathogen interaction, nodulation, cold response, flowering, and hormone signaling. However, little is known about the regulatory functions of the nucleoporin NUP160 and NUP96 in ethylene signaling pathway. In the present study, we provided data showing that the Arabidopsis nucleoporin NUP160 and NUP96 participate in ethylene signaling-related mRNAs nucleocytoplasmic transport. The Arabidopsis nucleoporin mutants (nup160, nup96-1, nup96-2) exhibited enhanced ethylene sensitivity. Nuclear qRT-PCR analysis and poly(A)-mRNA in situ hybridization showed that the nucleoporin mutants affected the nucleocytoplasmic transport of all the examined mRNAs, including the ethylene signaling-related mRNAs such as ETR2, ERS1, ERS2, EIN4, CTR1, EIN2, and EIN3. Transcriptome analysis of the nucleoporin mutants provided clues suggesting that the nucleoporin NUP160 and NUP96 may participate in ethylene signaling via various molecular mechanisms. These observations significantly advance our understanding of the regulatory mechanisms of nucleoporin proteins in ethylene signaling and ethylene response.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Nuclear Pore Complex Proteins/genetics , Nuclear Pore Complex Proteins/metabolism , Arabidopsis/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Ethylenes
7.
J Environ Sci (China) ; 126: 48-57, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36503774

ABSTRACT

Ultraviolet/persulfate (UV/PS) and Ultraviolet/hydrogen peroxide (UV/H2O2) have attracted much attention in recent years as advanced oxidation processes for water treatment. However, it is not all clear how these two methods affect the formation of cyanogen chloride (CNCl) in the subsequent water chlorination process. In this study, it was found that both UV/H2O2 and UV/PS pre-oxidation promoted the formation of CNCl in six actual water samples collected from urban rivers. Glycine, uric acid, arginine and histidine were investigated as the model compounds to explore the effects of different methods on the production of CNCl. The results showed that compared with chlorination alone, pre-oxidation by UV/H2O2 and UV/PS can reduce the production of CNCl for glycine and uric acid by up to 95% during post-chlorination process. However, they can greatly promote the formation of CNCl for arginine and histidine by up to 120-fold. In a more detailed investigation, pre-oxidation of histidine formed highly reactive intermediates to chlorine, leading to increased CNCl formation and chlorine consumption. The results showed that the precursors of CNCl was altered after pre-oxidation, and need to be re-evaluated.


Subject(s)
Fabaceae , Hydrogen Peroxide , Histidine , Uric Acid , Arginine , Glycine
8.
Cardiovasc Drugs Ther ; 36(2): 323-331, 2022 04.
Article in English | MEDLINE | ID: mdl-33791916

ABSTRACT

PURPOSE: We aimed to develop a simple risk score for patients with HFpEF and assessed the efficacy of spironolactone across baseline risk. METHODS: We developed risk stratification scheme for cardiovascular death in placebo arm of the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist trial (TOPCAT). We screened candidate risk indicators and determined strong risk predictors using COX regression. The absolute risk reduction (ARR) in cardiovascular death with spironolactone was evaluated across baseline risk groups. COX regressions were performed to assess the hazard ratios (HRs) of spironolactone therapy for cardiovascular death and drug discontinuation in each risk category. RESULTS: A simple risk score scheme was constructed based on five risk indicators weighted by estimates from the model, including age, diastolic blood pressure, renal dysfunction, white blood cell, and left ventricular ejection fraction. The risk score scheme showed good discrimination in placebo cohort (C index=0.70). ARR with spironolactone therapy was observed only in patients at very high risk (7.9%). Spironolactone therapy significantly reduced the risk of cardiovascular death in the very high-risk group (HR: 0.57; 95%CI, 0.39-0.84; P =0.005 and P for interaction 0.03) but showed similar risk of drug discontinuation across risk categories (P for interaction=0.928). CONCLUSION: This simple risk score stratifies patients with HFpEF by their baseline risk of cardiovascular death. Patients at very high risk derive great benefits from spironolactone therapy. This easy-to-use risk score provides a practical tool that can facilitate risk stratification and tailoring therapy for those who benefit most from spironolactone. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00094302.


Subject(s)
Heart Failure , Spironolactone , Heart Failure/diagnosis , Heart Failure/drug therapy , Hospitalization , Humans , Mineralocorticoid Receptor Antagonists/adverse effects , Risk Assessment , Spironolactone/adverse effects , Stroke Volume/physiology , Treatment Outcome , Ventricular Function, Left
9.
Int J Med Sci ; 19(13): 1920-1928, 2022.
Article in English | MEDLINE | ID: mdl-36438912

ABSTRACT

Background: A comprehensive understanding of phenotypes related to CKD will facilitate the identification and management of CKD. We aimed to panoramically test and validate associations between multiple phenotypes and CKD using a phenotype-wide association study (PheWAS). Methods: 15,815 subjects from cross-sectional cohorts of the National Health and Nutrition Examination Survey (1999-2006) were randomly 50:50 split into training and testing sets. CKD was defined as eGFR < 60 mL/min/1.73m2. We performed logistic regression analyses between each of 985 phenotypes with CKD in the training set (false discovery rate < 1%) and validated in the testing set (false discovery rate < 1% ). Random forest (RF) model, Nagelkerke's Pseudo-R2, and the area under the receiver operating characteristic (AUROC) were used to validate the identified phenotypes. Results: We identified 18 phenotypes significantly related to CKD, among which retinol, red cell distribution width (RDW), and C-peptide were less researched. The top 5 identified phenotypes were blood urea nitrogen (BUN), homocysteine (HCY), retinol, parathyroid hormone (PTH), and osmolality in RF importance ranking. Besides, BUN, HCY, PTH, retinol, and uric acid were the most important phenotypes based on Pseudo-R2. AUROC of the RF model was 0.951 (full model) and 0.914 (top 5 phenotypes). Conclusion: Our study demonstrated associations between multiple phenotypes with CKD from a holistic view, including 3 novel phenotypes: retinol, RDW, and C-peptide. Our findings provided valid evidence for the identification of novel biomarkers for CKD.


Subject(s)
Renal Insufficiency, Chronic , Humans , Renal Insufficiency, Chronic/diagnosis , Renal Insufficiency, Chronic/genetics , Nutrition Surveys , Cross-Sectional Studies , C-Peptide , Vitamin A , Phenotype
10.
Eur J Clin Invest ; 51(1): e13405, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32926588

ABSTRACT

BACKGROUND: In most situations, many patients undergoing coronary artery bypass graft (CABG) are on dual antiplatelet therapy (DAPT), which is also required after CABG. The adjustment of antiplatelet strategy remains controversial. In this study, we systematically review current guidelines, seeking consensus and controversies to facilitate clinical practice. METHODS AND RESULTS: Guidelines are searched in PubMed, Embase, ECRI Guidelines Trust and websites of guidelines organizations and professional society. Guidelines with recommendations of DAPT for patients undergo CABG are included. Two reviewers appraised guidelines with the Appraisal of Guidelines for Research and Evaluation II (AGREE II). Relevant recommendations are extracted and summarized. A total of 14 guidelines meeting inclusion criteria are selected, with average AGREE II scores from 44% to 86%. Most guidelines score high in domains other than 'applicability'. Many guidelines are not detailed enough in reporting considerations behind recommendations. Current guidelines are consistent on the management of antiplatelet strategy before elective CABG and using DAPT after surgery for preventing graft vessel occlusion. Evidence is still lacking in urgent CABG and resumption of the previous DAPT after surgery. CONCLUSIONS: Current guidelines on DAPT in CABG are generally satisfying. Suspending P2Y12 inhibitors while aspirin continued before elective CABG is recommended, as well as 12 months of DAPT following CABG. More evidence is needed to guide antiplatelet therapy in urgent CABG and to prove the benefits of resuming previous DAPT.


Subject(s)
Coronary Artery Bypass/methods , Coronary Artery Disease/surgery , Dual Anti-Platelet Therapy/methods , Practice Guidelines as Topic , Aspirin/therapeutic use , Deprescriptions , Duration of Therapy , Elective Surgical Procedures , Emergencies , Humans , Platelet Aggregation Inhibitors/therapeutic use , Postoperative Hemorrhage/prevention & control , Purinergic P2Y Receptor Antagonists/therapeutic use
11.
Circ J ; 85(9): 1545-1552, 2021 08 25.
Article in English | MEDLINE | ID: mdl-34135264

ABSTRACT

BACKGROUND: To examine the association of low educational attainment with incident heart failure (HF) and explore potential behavioral mediators of the causal pathway.Methods and Results:A total of 12,109 participants in the Atherosclerosis Risk in Communities Study (ARIC) were included. Educational attainment was measured at baseline, and the risk of HF across educational attainment groups was assessed by Cox proportional hazards models. Using mediation analysis, we evaluated the mediating role of behavioral factors in the causal pathway between educational attainment and HF. During a median follow-up of 25.1 years, 2,407 cases (19.9%) of HF occurred. Educational attainment showed an inverse association with HF risk (hazard ratio (HR), 1.41; 95% confidence interval (CI), 1,26-1.57 for low educational attainment; HR, 1.13; 95% CI, 1.02-1.25 for medium educational attainment). In the mediation analysis, the association between educational attainment and HF was partially mediated by income, waist-to-hip ratio, current smoking, body mass index, current drinking, sports and physical activity, which explained 24.3%, 20.2%, 13.8%, 10.1%, 7.7%, 7.3% and 4.5%, respectively, of the relationship. In total, all mediators contributed 56.3% of the total effect. CONCLUSIONS: Low educational attainment was associated with increased risk for HF. Income, obesity and current smoking mediated a great proportion of the total effect of educational attainment on HF. Our results provide underlying insights for the development of targeted public health interventions to reduce educational disparities on HF incidence.


Subject(s)
Heart Failure , Mediation Analysis , Body Mass Index , Exercise , Heart Failure/complications , Humans , Obesity/complications , Obesity/epidemiology
12.
BMC Infect Dis ; 21(1): 92, 2021 Jan 21.
Article in English | MEDLINE | ID: mdl-33478412

ABSTRACT

BACKGROUND: Echocardiography (echo) is the primary imaging modality for infective endocarditis (IE). However, the recommendations on timing and mode selection for transesophageal echocardiography (TEE) and transthoracic echocardiography (TTE) vary across guidelines, which can be confusing for clinical decision makers. In this case, we aim to appraise the quality of recommendations by appraising the quality of various guidelines. METHODS: A search of guidelines containing recommendations for the appropriate use of echo in adult IE patients published in English between 2007 and 2019 was conducted. The APPRAISAL OF GUIDELINES FOR RESEARCH & EVALUATION II (AGREE II) instrument was applied independently by two reviewers to assess the integrated quality of the identified guidelines. The recommendations of concern are extracted from related chapters. RESULTS: A total of 9 guidelines met the criteria, with AGREE II scores ranging from 36 to 79%, and the domain of "stakeholder involvement" received the lowest score. The most contentious issue is whether a follow-up TEE is mandatory in uncomplicated native valve IE with an initial positive TTE. Conflicting recommendations are presented with a low evidence level based on little evidence. CONCLUSIONS: In general, the recommendations proposed in the 9 identified guidelines on the appropriate use of echo are satisfying. The guideline quality score can be taken into account by the clinicians when evaluating the recommendations for clinical decisions. Additional studies with high evidence level should be conducted on the most controversial issues of whether a subsequent TEE is mandatory in uncomplicated native valve IE with an initial positive TTE.


Subject(s)
Echocardiography/standards , Endocarditis/diagnostic imaging , Practice Guidelines as Topic/standards , Adult , Echocardiography/methods , Echocardiography, Transesophageal/methods , Echocardiography, Transesophageal/standards , Humans
13.
BMC Cardiovasc Disord ; 21(1): 288, 2021 06 10.
Article in English | MEDLINE | ID: mdl-34112089

ABSTRACT

BACKGROUND: Atrioventricular (AV) delay could affect AV and ventricular synchrony in cardiac resynchronization therapy (CRT). Strategies to optimize AV delay according to optimal AV synchrony (AVopt-AV) or ventricular synchrony (AVopt-V) would potentially be discordant. This study aimed to explore a new AV delay optimization algorithm guided by electrograms to obtain the maximum integrative effects of AV and ventricular resynchronization (opt-AV). METHODS: Forty-nine patients with CRT were enrolled. AVopt-AV was measured through the Ritter method. AVopt-V was obtained by yielding the narrowest QRS. The opt-AV was considered to be AVopt-AV or AVopt-V when their difference was < 20 ms, and to be the AV delay with the maximal aortic velocity-time integral between AVopt-AV and AVopt-V when their difference was > 20 ms. RESULTS: The results showed that sensing/pacing AVopt-AV (SAVopt-AV/PAVopt-AV) were correlated with atrial activation time (Pend-As/Pend-Ap) (P < 0.05). Sensing/pacing AVopt-V (SAVopt-V/PAVopt-V) was correlated with the intrinsic AV conduction time (As-Vs/Ap-Vs) (P < 0.01). The percentages of patients with more than 20 ms differences between SAVopt-AV/PAVopt-AV and SAVopt-V/PAVopt-V were 62.9% and 57.1%, respectively. Among them, opt-AV was linearly correlated with SAVopt-AV/PAVopt-AV and SAVopt-V/PAVopt-V. The sensing opt-AV (opt-SAV) = 0.1 × SAVopt-AV + 0.4 × SAVopt-V + 70 ms (R2 = 0.665, P < 0.01) and the pacing opt-AV (opt-PAV) = 0.25 × PAVopt-AV + 0.5 × PAVopt-V + 30 ms (R2 = 0.560, P < 0.01). CONCLUSION: The SAVopt-AV/PAVopt-AV and SAVopt-V/PAVopt-V were correlated with the atrial activation time and the intrinsic AV conduction interval respectively. Almost half of the patients had a > 20 ms difference between SAVopt-AV/PAVopt-AV and SAVopt-V/PAVopt-V. The opt-AV could be estimated based on electrogram parameters.


Subject(s)
Action Potentials , Arrhythmias, Cardiac/therapy , Cardiac Resynchronization Therapy , Electrocardiography , Electrophysiologic Techniques, Cardiac , Heart Rate , Aged , Arrhythmias, Cardiac/diagnosis , Arrhythmias, Cardiac/physiopathology , China , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Recovery of Function , Signal Processing, Computer-Assisted , Time Factors , Treatment Outcome
14.
Pacing Clin Electrophysiol ; 44(3): 462-471, 2021 03.
Article in English | MEDLINE | ID: mdl-33433929

ABSTRACT

BACKGROUND: Epicardial to endocardial breakthrough (EEB) exists widely in atrial arrhythmia and is a cause for intractable cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL). This study aimed to investigate the electrophysiological features of EEB in EEB-related CTI dependent AFL. METHODS: Six patients with EEB-related CTI-dependent AFL were identified among 142 consecutive patients who underwent CTI-dependent AFL catheter ablation with an ultra-high-density, high-resolution mapping system in three institutions. Activation maps and ablation procedure were analyzed. RESULTS: A total of seven EEBs were found in six patients. Four EEBs (including three at the right atrial septum and one in paraseptal isthmus) were recorded in three patients during tachycardia. The other three EEBs were identified at the inferolateral right atrium (RA) during pacing from the coronary sinus. The conduction characteristics through the EEB-mediated structures were evaluated in three patients. Two patients only showed unidirectional conduction. Activation maps indicated that CTI-dependent AFL with EEB at the atrial septum was actually bi-atrial macro-reentrant atrial tachycardia (BiAT). Intensive ablation at the central isthmus could block CTI bidirectionally in four cases. However, ablation targeted at the inferolateral RA EEB was required in two cases. Meanwhile, local potentials at the EEB location gradually split into two components with a change in activation sequence. CONCLUSIONS: EEB is an underlying cause for intractable CTI-dependent AFL. EEB-mediated structure might show unidirectional conduction. CTI-dependent AFL with EEB at the atrial septum may represent BiAT. Intensive ablation targeting the central isthmus or EEB at the inferolateral RA could block the CTI bidirectionally.


Subject(s)
Atrial Flutter/physiopathology , Atrial Flutter/surgery , Catheter Ablation/methods , Endocardium/physiopathology , Heart Conduction System/physiopathology , Adult , Aged , Electrophysiologic Techniques, Cardiac , Epicardial Mapping , Female , Humans , Male , Middle Aged , Tricuspid Valve/physiopathology , Tricuspid Valve/surgery
15.
Int Heart J ; 62(1): 178-180, 2021.
Article in English | MEDLINE | ID: mdl-33518656

ABSTRACT

Speech-induced atrial tachycardia (AT) is extremely rare. We presented a case of focal AT that could be triggered by speech and terminated with the cessation of conversation. An electrophysiological study showed that the outbreak was associated with left atrial pressure rose. Radiofrequency ablation at the left atrial posterior-superior wall (earliest activation site) resulted in the immediate termination of AT. These electrophysiological characteristics indicated that the cardiac autonomic nervous system and/or left atrial pressure might play essential roles in the occurrences of speech-induced AT.


Subject(s)
Speech , Tachycardia, Supraventricular/etiology , Aged , Catheter Ablation , Electrocardiography , Female , Humans , Tachycardia, Supraventricular/therapy
16.
J Cardiovasc Pharmacol ; 76(6): 692-697, 2020 12.
Article in English | MEDLINE | ID: mdl-32889964

ABSTRACT

The effect of renin-angiotensin-aldosterone system (RAAS) blockers [angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers] on Contrast-induced nephropathy (CIN) is unclear in patients with renal insufficiency. Thus, we conduct a meta-analysis to evaluate the association between the administration of RAAS blockers and CIN in patients with renal insufficiency. We searched PubMed, EMBASE, and Cochrane Library for relevant studies published before September 2019. The primary outcome was the incidence of CIN, and the secondary outcome was the changes in serum creatinine (SCr) from baseline to postprocedure (ΔSCr). Pooled odds ratio (OR) or weighted mean difference (WMD) with their 95% confidence interval (CIs) for the CIN incidence, ΔSCr were used to calculate original data. A total of 8 studies were included in the meta-analysis. Compared with controls, ACEI/angiotensin receptor blocker increased the risk of CIN (OR = 1.61, 95% CI 1.14-2.28, I = 30%; P = 0.007), whereas this association was not significant in Chinese patients (OR = 1.07, 95% CI 0.65-1.77, I = 19%, P = 0.79). The total weighted mean differences of the ΔSCr were 0.06 mg/dL (95% CI: 0.01-0.11, I = 82%; P = 0.03). Administration of RAAS blockers in patients with renal insufficiency was associated with a significantly higher incidence of CIN, whereas it did not show a significant effect on Chinese patients.


Subject(s)
Acute Kidney Injury/prevention & control , Angiotensin Receptor Antagonists/therapeutic use , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Contrast Media/adverse effects , Kidney/drug effects , Renal Insufficiency/complications , Renin-Angiotensin System/drug effects , Acute Kidney Injury/chemically induced , Acute Kidney Injury/diagnosis , Acute Kidney Injury/physiopathology , Angiotensin Receptor Antagonists/adverse effects , Angiotensin-Converting Enzyme Inhibitors/adverse effects , Humans , Kidney/pathology , Kidney/physiopathology , Renal Insufficiency/diagnosis , Renal Insufficiency/physiopathology , Risk Assessment , Risk Factors , Treatment Outcome
17.
J Cardiovasc Electrophysiol ; 30(5): 642-650, 2019 05.
Article in English | MEDLINE | ID: mdl-30680820

ABSTRACT

INTRODUCTION: Right ventricular outflow tract ventricular arrhythmias (RVOT VAs) often originate in the voltage-transitional zone. The target electrogram could be compromised by the architecture of the roving catheter. Mini-electrodes could improve the mapping resolution, especially in low-voltage areas. The aim was to assess the electrophysiological characteristics of the earliest activation site (EAS) of RVOT VAs during mapping using mini-electrodes. METHODS AND RESULTS: Twenty-seven patients with RVOT-type VAs were mapped using Orion mini-electrodes and the Rhythmia mapping system. Bipolar and unipolar electrograms were analyzed and compared with conventional ablation catheter recordings. Twenty-five patients (25 of 27) were successfully mapped and ablated at the RVOT. At the EAS, all 25 (100%) patients exhibited local sharp potentials (spiky potential) at the VAs, and 88% (22 of 25) individuals showed reverse late potentials in adjacent sinus beats on the bipolar mini-electrode recordings. Related unipolar electrograms manifested 20% "q-plateau-QS," 76% "gross QS," and 4% "late QS" patterns related to spiky potential voltages and advanced times. Compared with electrograms recorded by ablation catheter, bipolar mini-electrode recordings exhibited significantly shorter spiky potential durations (P = 0.001) and a significantly increased incidence of the reverse late potentials (P = 0.041). Unipolar mini-electrode recordings had a lower incidence ratio of "late QS" patterns (P = 0.039). CONCLUSION: Compared with ablation catheter mapping, mini-electrodes improved the mapping resolution of the EAS of RVOT VAs and exhibited shorter spiky potential durations and reduced incidence of "later QS" unipolar patterns.


Subject(s)
Action Potentials , Arrhythmias, Cardiac/diagnosis , Electrophysiologic Techniques, Cardiac/instrumentation , Heart Conduction System/physiopathology , Heart Rate , Heart Ventricles/physiopathology , Microelectrodes , Adult , Arrhythmias, Cardiac/physiopathology , Arrhythmias, Cardiac/surgery , Catheter Ablation , Equipment Design , Female , Heart Conduction System/surgery , Heart Ventricles/surgery , Humans , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , Reproducibility of Results , Time Factors , Treatment Outcome
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(4): 894-7, 2014 Apr.
Article in Zh | MEDLINE | ID: mdl-25007594

ABSTRACT

In the present paper, an innovative experiment was done. The authors measured the Raman spectra of CS2 mixed with THF at different volume fractions. According to the J. F. Bertran theory, we analyzed the changing regularity of v1-2v2 Fermi resonance along with the different concentration. It was shown that the characteristic parameters of Fermi resonance in solution, such as spectra intensity, frequency space, coupling coefficient and anharmonic constant, will make changes along with solution concentration variation. Because of the existing of solvent effects, the spectra intensity decreases gradually, and the coupling coefficient increases gradually. The explanation of such changes is that the vibration spectra are affected not only by scattering coefficient, but also by more weak hydrogen bond's formation. In addition, the asymmetric frequency shift of the Raman spectra was also found in the paper. The fundamental frequency v1 basically has no shifts, but the overtone frequency 2v2 moves towards the high wave number gradually, which is inconsistent with the theory of symmetrical movement. According to the study of molecular microcosmic action, the formation and mechanism of the weak hydrogen bond can preferably explain the above phenomenon. The research has a major influence on the further study of solvent effects in Fermi resonance. And the paper will also provide certain reference value for the study of molecule vibration spectra in solution.

20.
Chem Commun (Camb) ; 60(14): 1872-1875, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38240726

ABSTRACT

The pressure dependent reaction mechanism of CO2 hydrogenation over In2O3 was investigated. CO2 hydrogenation on In2O3 can produce methanol only at high pressure, while the atmospheric pressure operation leads to the formation of CO. The conversion from HCOO* to H3CO* is accelerated at high pressure, leading to the formation of methanol with the formate route (CO2* → HCOO* → H3CO* → H3COH).

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