Insights into the evolutionary and ecological adaption strategies of nirS- and nirK-type denitrifying communities.

Denitrification is a crucial process in the global nitrogen cycle, in which two functionally equivalent genes, nirS and nirK, catalyse the critical reaction and are usually used as marker genes. The nirK gene can function independently, whereas nirS requires additional genes to encode nitrite reductase and is more sensitive to environmental factors than nirK. However, the ecological differentiation mechanisms of those denitrifying microbial communities and their adaptation strategies to environmental stresses remain unclear. Here, we conducted metagenomic analysis for sediments and bioreactor samples from Lake Donghu, China. We found that nirS-type denitrifying communities had a significantly lower horizontal gene transfer frequency than that of nirK-type denitrifying communities, and nirS gene phylogeny was more congruent with taxonomy than that of nirK gene. Metabolic reconstruction of metagenome-assembled genomes further revealed that nirS-type denitrifying communities have robust metabolic systems for energy conservation, enabling them to survive under environmental stresses. Nevertheless, nirK-type denitrifying communities seemed to adapt to oxygen-limited environments with the ability to utilize various carbon and nitrogen compounds. Thus, this study provides novel insights into the ecological differentiation mechanism of nirS and nirK-type denitrifying communities, as well as the regulation of the global nitrogen cycle and greenhouse gas emissions.

Direct Oral Anticoagulants for Treating Acute Venous Thromboembolism in Children: Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Acute venous thromboembolism (VTE) in children presents unique challenges due to the limitations of standard anticoagulation therapies. Herein, we aimed to systematically review randomized controlled trials (RCTs) evaluating the efficacy and safety of direct oral anticoagulants (DOACs) in pediatric patients with acute VTE. METHODS: PubMed and Embase databases were searched for RCTs comparing DOACs to standard anticoagulation in pediatric VTE patients. Efficacy outcomes included VTE recurrence and all-cause mortality, while safety outcomes comprised major bleeding and other adverse events. RESULTS: Three RCTs with 790 participants were included. When compared with standard anticoagulation, DOACs demonstrated a reduced risk of VTE recurrence (risk difference[RD] = -3%, 95% confidence interval[CI]: -6% to 0%, P = 0.04) and an increased risk of any adverse event (RD = 8%, 95% CI: 1% to 14%, P = 0.02). No significant differences were found in all-cause mortality, major bleeding, clinically relevant non-major bleeding, or total bleeding between the DOAC and control groups. CONCLUSION: DOACs, primarily dabigatran and rivaroxaban, are non-inferior to standard anticoagulants in reducing VTE recurrence in pediatric patients, with comparable safety profiles. Further research is essential to confirm these findings.

Association of COPD with adverse outcomes in heart failure patients with preserved ejection fraction.

We performed a systematic review and meta-analysis to detect the impact of chronic obstructive pulmonary disease (COPD) on the prognosis of heart failure patients with preserved ejection fraction (HFpEF). We systematically screened eligible literature from three electronic databases, PubMed, EMBASE and Cochrane Library, up to April 2023. Two researchers participated in data collection independently. Risk ratios (RRs) from included studies with 95% confidence intervals (CIs) were pooled in the Review Manager version 5.40 software using a random-effects model for analysis. A total of 11 studies (3 post hoc analyses of RCTs and 8 observational studies) with 18 602 participants were included in this meta-analysis. After pooling all the data from eligible studies, our results indicated that COPD was associated with an increased risk of hospitalization (RR = 1.66, 95% CI, 1.47-1.87, P < 0.00001), mortality (RR = 1.62, 95% CI, 1.34-1.95, P < 0.00001), and the composition of hospitalization or mortality (RR = 1.84, 95% CI, 1.35-2.51, P < 0.001) in patients with HFpEF. In a subgroup analysis, the risks of cardiovascular-related mortality (RR = 1.59, 95% CI, 1.30-1.93, P < 0.00001) and post-discharge mortality risk (RR = 2.57, 1.34-4.93, P < 0.01) were increased in HFpEF patients comorbid with COPD, and these associations were also detected in HF-caused hospitalization (RR = 1.64, 95% CI, 1.44-1.87, P < 0.00001). Evidence from existing studies supported that COPD was an independent prognostic risk factor for patients with HFpEF. Developing rapid clinical diagnostic indicators and early use of novel drugs such as SGLT-2 and ARNI may improve the prognosis of this population, deserving further study.

Real-world evidence of early rhythm control in patients with atrial fibrillation: A systematic review and meta-analysis.

BACKGROUND: The favorable benefits of early rhythm control (ERC) therapy in newly diagnosed patients with atrial fibrillation (AF) have been demonstrated in the EAST-AFNET 4 trial. However, the generalizability and applicability of ERC in real-world clinical settings remain inconclusive. METHODS: We conducted a systematic search of the PubMed and Embase databases to identify observational studies published between January 2020 and February 2024 that focused on real-world evidence pertaining to ERC. The effectiveness and safety outcomes in our study were analogous to those evaluated in the EAST-AFNET 4 trial. RESULTS: A total of 4 observational studies that fulfilled the inclusion criteria of EAST-AFNET 4 were included, involving 130,970 patients with AF, 30.7% of whom received ERC therapy. In our pooled analysis using the fixed-effects model, compared with rate control, ERC significantly decreased the occurrence risk of the primary composite outcome (hazard ratio [HR] 0.86, 95% confidence interval[CI] 0.82-0.91), cardiovascular death (HR 0.87, 95% CI 0.78-0.98), stroke (HR 0.80, 95% CI 0.73-0.87), and hospitalization with worsening heart failure (HR 0.91, 95% CI 0.84-0.99) or acute coronary syndrome (HR 0.72, 95% CI 0.59-0.87). In terms of safety outcomes, there were no differences in the composite safety outcome (HR 1.00, 95% CI 0.95-1.05) and all-cause death (HR 0.93, 95% CI 0.82-1.06) between the two studied groups. CONCLUSIONS: ERC therapy showed favorable effectiveness outcomes compared with rate control, whereas the safety outcomes between the two therapeutic strategies did not differ significantly, supporting the benefits of ERC therapy over rate control in selected real-world patients with AF. REGISTRATION: The study protocol was registered to PROSPERO (CRD42023443569).

The use of non-vitamin K antagonist oral anticoagulants in chronic thromboembolic pulmonary hypertension: an updated meta-analysis.

Studies have demonstrated the beneficial effects of non-vitamin K antagonist oral anticoagulants (NOACs) for the treatment of atrial fibrillation and venous thromboembolism (VTE). The impact of NOACs on chronic thromboembolic pulmonary hypertension (CTEPH) remains controversial. This meta-analysis was conducted to investigate the effectiveness and safety of NOACs compared with vitamin K antagonists (VKAs) in patients with CTEPH. A comprehensive search of PubMed, Embase, and Cochrane Library was conducted for relevant studies, encompassing data from inception until November 2023. The data were pooled using a fixed-effects model if the I2 value was less than 50%; otherwise, a random-effects model was employed. Overall, two randomized controlled trials (RCTs) and eight observational studies involving 4556 patients with CTEPH were included. Patients receiving NOACs exhibited a significantly lower incidence of all-cause mortality (odds ratio [OR] = 0.52, 95% confidence interval [CI]: 0.36-0.76) and major bleeding (OR = 0.58, 95% CI: 0.36-0.92) compared to those with VKAs. There were no significant differences in the rate of VTE recurrence (OR = 1.07, 95% CI: 0.72-1.59), total bleeding (OR = 0.78, 95% CI: 0.60-1.01), and minor bleeding (OR = 1.11, 95% CI: 0.73-1.69) between the two studied groups. Similar results were found in the subgroup analysis and sensitivity analysis.This meta-analysis provided evidence that NOACs could be superior to VKAs for the treatment of CTEPH. NOACs might be safe and a convenient alternative to VKAs for thromboprophylaxis in patients with CTEPH.

Lactate and lactylation in cardiovascular diseases: current progress and future perspectives.

Cardiovascular diseases (CVDs) are often linked to structural and functional impairments, such as heart defects and circulatory dysfunction, leading to compromised peripheral perfusion and heightened morbidity risks. Metabolic remodeling, particularly in the context of cardiac fibrosis and inflammation, is increasingly recognized as a pivotal factor in the pathogenesis of CVDs. Metabolic syndromes further predispose individuals to these conditions, underscoring the need to elucidate the metabolic underpinnings of CVDs. Lactate, a byproduct of glycolysis, is now recognized as a key molecule that connects cellular metabolism with the regulation of cellular activity. The transport of lactate between different cells is essential for metabolic homeostasis and signal transduction. Disruptions to lactate dynamics are implicated in various CVDs. Furthermore, lactylation, a novel post-translational modification, has been identified in cardiac cells, where it influences protein function and gene expression, thereby playing a significant role in CVD pathogenesis. In this review, we summarized recent advancements in understanding the role of lactate and lactylation in CVDs, offering fresh insights that could guide future research directions and therapeutic interventions. The potential of lactate metabolism and lactylation as innovative therapeutic targets for CVD is a promising avenue for exploration.

Comprehensive profiles of sulfur cycling microbial communities along a mangrove sediment depth.

The sulfur (S) cycle is an important biogeochemical cycle with profound implications for both cellular- and ecosystem-level processes by diverse microorganisms. Mangrove sediments are a hotspot of biogeochemical cycling, especially for the S cycle with high concentrations of S compounds. Previous studies have mainly focused on some specific inorganic S cycling processes without paying specific attention to the overall S-cycling communities and processes as well as organic S metabolism. In this study, we comprehensively analyzed the distribution, ecological network and assembly mechanisms of S cycling microbial communities and their changes with sediment depths using metagenome sequencing data. The results showed that the abundance of gene families involved in sulfur oxidation, assimilatory sulfate reduction, and dimethylsulfoniopropionate (DMSP) cleavage and demethylation decreased with sediment depths, while those involved in S reduction and dimethyl sulfide (DMS) transformation showed an opposite trend. Specifically, glpE, responsible for converting S2O32- to SO32-, showed the highest abundance in the surface sediment and decreased with sediment depths; in contrast, high abundances of dmsA, responsible for converting dimethyl sulfoxide (DMSO) to DMS, were identified and increased with sediment depths. We identified Pseudomonas and Streptomyces as the main S-cycling microorganisms, while Thermococcus could play an import role in microbial network connections in the S-cycling microbial community. Our statistical analysis showed that both taxonomical and functional compositions were generally shaped by stochastic processes, while the functional composition of organic S metabolism showed a transition from stochastic to deterministic processes. This study provides a novel perspective of diversity distribution of S-cycling functions and taxa as well as their potential assembly mechanisms, which has important implications for maintaining mangrove ecosystem functions.

Association of hypertension burden with stroke risk in patients with heart failure with preserved ejection fraction.

Introduction: Whether the hypertension burden is associated with stroke incidence is inconclusive. In this study, we aimed to investigate the relationship between hypertension burden and stroke risk in patients with heart failure with preserved ejection fraction (HFpEF). Methods: HFpEF patients from the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial were divided into three groups (low, medium, and high risk) according to their hypertension burden values. Higher hypertension burden risk represented the longer duration of hypertension. We evaluated the association of hypertension burden with stroke risk using Fine and Gray's competing risk models. Results: A total of 3431 HFpEF patients (mean age: 68.5 ± 9.58 years, 51.6% females) were enrolled. During a median follow-up of 3.3 years, per 10-point increase in hypertension burden was associated with any stroke (hazard ratio [HR] 1.15, 95% confidence interval [CI] 1.08-1.21), new-onset stroke (HR 1.14, 95% CI 1.07-1.21), and ischemic stroke (HR 1.10, 95% CI 1.02-1.17). When hypertension burden was analyzed as a categorical variable, any stroke risk was increased in the medium- (HR 1.59, 95% CI 1.01-2.40) and high-risk (HR 3.19, 95% CI 2.05-4.97) groups when compared with the low-risk group. For the outcomes of new-onset (HR 2.92, 95% CI 1.80-4.74) and ischemic stroke (HR 2.46, 95% CI 1.41-4.29), similar results were observed in patients with high-versus low-risk hypertension burden. Conclusions: Increasing hypertension burden was associated with an increased risk of stroke, suggesting that shortening hypertension duration might appropriately minimize the stroke incidence in HFpEF patients.

S2I2N0-3 score predicts short- and long-term mortality and morbidity in HFrEF: a post-hoc analysis of the GUIDE-IT trial.

AIMS: This study investigated the S2I2N0-3 score, a simple tool comprising stroke history, insulin-treated diabetes, and N-terminal pro-brain natriuretic peptide, for forecasting mortality and morbidity in heart failure (HF) with reduced ejection fraction (HFrEF). METHODS AND RESULTS: Analysing 890 GUIDE-IT HFrEF trial participants, we stratified them by baseline S2I2N0-3 risk score into three risk groups. We examined the score's association with five adverse outcomes over short (90 days) and extended periods (median follow-up of 15 months) using Cox and competing risk models. Our analysis revealed significant positive associations between the S2I2N0-3 strata and adverse outcomes. When analysed as a continuous variable, each point increment of the S2I2N0-3 score was associated with a higher risk of short- and long-term cardiovascular death [short term: hazard ratio (HR) 1.43, 95% confidence interval (CI) 1.03-1.98; long term: HR 1.18, 95% CI 1.02-1.38], all-cause death (HR 1.52, 95% CI 1.12-2.07; HR 1.18, 95% CI 1.03-1.36), HF hospitalization (HR 1.39, 95% CI 1.20-1.62; HR 1.18, 95% CI 1.06-1.31), any hospitalization (HR 1.19, 95% CI 1.06-1.34; HR 1.09, 95% CI 1.00-1.19), and the composite outcome of cardiovascular death and HF hospitalization (HR 1.39, 95% CI 1.21-1.60; HR 1.17, 95% CI 1.06-1.30). The S2I2N0-3 demonstrated reliable prognostic value, with C-indices ranging from 0.619 to 0.753 across outcomes and time points. When compared with the Meta-Analysis Global Group in Chronic Heart Failure (MAGGIC) score using Z-statistics, net reclassification index, and integrated discrimination improvement, the S2I2N0-3 showed comparable predictive power for all outcomes during both short- and long-term follow-ups. CONCLUSIONS: The S2I2N0-3 risk score had modest predictive values for both short- and long-term clinical outcomes in HFrEF patients, offering equivalent performance to the established MAGGIC score.

Performance of ChatGPT on the Chinese Postgraduate Examination for Clinical Medicine: Survey Study.

BACKGROUND: ChatGPT, an artificial intelligence (AI) based on large-scale language models, has sparked interest in the field of health care. Nonetheless, the capabilities of AI in text comprehension and generation are constrained by the quality and volume of available training data for a specific language, and the performance of AI across different languages requires further investigation. While AI harbors substantial potential in medicine, it is imperative to tackle challenges such as the formulation of clinical care standards; facilitating cultural transitions in medical education and practice; and managing ethical issues including data privacy, consent, and bias. OBJECTIVE: The study aimed to evaluate ChatGPT's performance in processing Chinese Postgraduate Examination for Clinical Medicine questions, assess its clinical reasoning ability, investigate potential limitations with the Chinese language, and explore its potential as a valuable tool for medical professionals in the Chinese context. METHODS: A data set of Chinese Postgraduate Examination for Clinical Medicine questions was used to assess the effectiveness of ChatGPT's (version 3.5) medical knowledge in the Chinese language, which has a data set of 165 medical questions that were divided into three categories: (1) common questions (n=90) assessing basic medical knowledge, (2) case analysis questions (n=45) focusing on clinical decision-making through patient case evaluations, and (3) multichoice questions (n=30) requiring the selection of multiple correct answers. First of all, we assessed whether ChatGPT could meet the stringent cutoff score defined by the government agency, which requires a performance within the top 20% of candidates. Additionally, in our evaluation of ChatGPT's performance on both original and encoded medical questions, 3 primary indicators were used: accuracy, concordance (which validates the answer), and the frequency of insights. RESULTS: Our evaluation revealed that ChatGPT scored 153.5 out of 300 for original questions in Chinese, which signifies the minimum score set to ensure that at least 20% more candidates pass than the enrollment quota. However, ChatGPT had low accuracy in answering open-ended medical questions, with only 31.5% total accuracy. The accuracy for common questions, multichoice questions, and case analysis questions was 42%, 37%, and 17%, respectively. ChatGPT achieved a 90% concordance across all questions. Among correct responses, the concordance was 100%, significantly exceeding that of incorrect responses (n=57, 50%; P<.001). ChatGPT provided innovative insights for 80% (n=132) of all questions, with an average of 2.95 insights per accurate response. CONCLUSIONS: Although ChatGPT surpassed the passing threshold for the Chinese Postgraduate Examination for Clinical Medicine, its performance in answering open-ended medical questions was suboptimal. Nonetheless, ChatGPT exhibited high internal concordance and the ability to generate multiple insights in the Chinese language. Future research should investigate the language-based discrepancies in ChatGPT's performance within the health care context.