22 research outputs found
Continuous Positive Airway Pressure Therapy and Long-Term Outcomes in Patients with Coronary Artery Disease and Obstructive Sleep Apnea: A Meta-Analysis of Randomized Trials
Background: Obstructive sleep apnea (OSA) is highly common in patients with coronary artery disease (CAD) and it is a strong predictor of subsequent cardiovascular events. However, whether treatment with continuous positive airway pressure (CPAP) can decrease this risk remains controversial. Methods: PubMed, EMBASE, the Cochrane Library, and ClinicalTrials.gov were systematically searched to identify randomized clinical trials reporting cardiovascular events from database inception to February 12, 2022. Results : Four trials with 3043 participants were included. The median follow-up duration ranged from 3 to 4.75 years. Compared with usual care alone, CPAP was not associated with decreased MACCE risk (RR 0.96, 95% CI 0.77–1.21, P = 0.75), and the results were consistent regardless of CPAP adherence (≥4 hours/night vs. <4 hours/night, RR 0.48, 95% CI 0.20–1.16). Similarly, no significant differences were observed between groups in the risks of all-cause death (RR 0.81, 95% CI 0.52–1.26), cardiovascular death (RR 0.70, 95% CI 0.36–1.33), myocardial infarction (RR 1.08, 95% CI 0.73–1.60), revascularization (RR 1.03, 95% CI 0.77–1.38), and cerebrovascular events (RR 0.77, 95% CI 0.23–2.61). Conclusion: Existing evidence does not support an association between CPAP treatment and decreased risk of recurrent cardiovascular events in patients with CAD and OSA, regardless of adherence to CPAP
Environmental contamination characteristics of heavy metals from abandoned lead–zinc mine tailings in China
China holds large-scale lead–zinc mineral resources; however, mining activities often cause severe contamination by heavy metals. This study systemically assessed contamination by eight heavy metals (Cu, Zn, Cd, Pb, Cr, Hg, Ni, and As) in mine tailings, soil, and groundwater from 27 contaminated sites across China. Regarding mine tailings, 1% of the mine tailing samples were hazardous waste and 20% were class II non-hazardous waste. Regarding soil, Zn and Pb showed the highest mean concentrations, at 5574.67 mg/kg and 2034.88 mg/kg, respectively. The indexes of geo-accumulation (Igeo) of eight heavy metals ranged from −3.62 to 7.67, while Zn, Pb, and Cd showed the highest environmental risk levels as the priority pollutants. The contamination levels of these heavy metals in groundwater were generally in the order of Zn>As>Pb>Ni>Cd>Cu>Hg>Cr. In this study, 20% of the soil and 10% of the groundwater samples exceeded the corresponding quality limits. The content of heavy metals in soil, groundwater, and mine tailing were positively correlated, demonstrating the main pollution source and transport paths. The pollution levels of heavy metals in soil and groundwater were listed in the foremost and moderate positions compared with similar sites from other countries, respectively. These results may help determine the pollution levels of lead–zinc mining regions and direct the remediation activities of target sites to support the environmental management of abandoned mining and tailing waste in China
Rationale and Design of the RESTORE Trial: A Multicenter, Randomized, Double-Blinded, Parallel-Group, Placebo-Controlled Trial to Evaluate the Effect of Shenfu Injection on Myocardial Injury in STEMI Patients After Primary PCI
BACKGROUND: The mortality following ST-segment elevation myocardial infarction (STEMI) remains substantial in the reperfusion era. Shenfu injection, as a traditional Chinese herbal formula, can alleviate ischemia-reperfusion injury through multiple pharmacologic effects. However, no robust data are available regarding the role of Shenfu injection in reducing infarct size for patients with STEMI undergoing primary percutaneous coronary intervention (PPCI).
METHODS/DESIGN: This RESTORE trial is a multicenter, randomized, double-blind, parallel-group, placebo-controlled trial (NCT04493840). A total of 326 eligible patients with first-time anterior STEMI undergoing PPCI within 12 h of symptom onset will be enrolled from 10 centers in mainland China. Patients are randomized in a 1:1 fashion to receive either intravenous Shenfu injection (80mL Shenfu injection + 70mL 5% glucose injection) or placebo group (150mL 5% glucose injection) before reperfusion and followed by once a day until 5 days after PPCI. The primary end point is infarct size assessed by cardiac magnetic resonance (CMR) imaging 5±2 days after PPCI. The major secondary end points include enzymatic infarct size, microvascular obstruction, intramyocardial hemorrhage, left ventricular volume and ejection fraction assessed by CMR, as well as cardiovascular events at 30 days.
CONCLUSIONS: The RESTORE trial is sufficiently powered to demonstrate the clinical effects of Shenfu injection on myocardial injury in STEMI patients undergoing PPCI in the contemporary era
Large expert-curated database for benchmarking document similarity detection in biomedical literature search
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
SAFETY ASSESSMENT OF CONTINUOUS CONCRETE GIRDER BRIDGES SUBJECTED TO RANDOM TRAFFIC LOADS CONSIDERING FLEXURAL-SHEAR COUPLED FAILURE
Bridges generally perform complicated mechanical behaviors under external loads, such as flexural-shear coupling, compression-bending coupling, and flexural-shear-torsion coupling. In the context of deterministic design approaches such as design codes, these complicated coupled issues are generally simplified to the safety verification of bridge components under a single mechanical state (i.e. flexural, shear, torsion). At present, the rapid development of sensor and information technologies makes it possible to collect the external loads acted on bridges and understand bridge performance under these stochastic external loads. In this manner, the reliability-based full probabilistic approach could be applied to investigate the performance of bridges over their lifetime. However, the current bridge reliability assessment incorporating realistic traffic load measurements mainly focuses on the analysis of bridge components under a single mechanical state. In this paper, a reliability-based probabilistic analytical framework of the flexural-shear performance of girder bridges under random traffic loading is established. The flexural-shear coupled failure path of bridge girders under random traffic loading is characterized for the first time, where the bivariate extreme value theory is incorporated to develop the extreme value distribution of combined flexural and shear load effects. The modified compression field theory recommended by AASHTO is employed to establish the coupled flexural-shear coupling resistances. Finally, the reliability of the flexural-shear performance of bridge girders is evaluated by solving the multivariate ultimate limit state equation. The proposed analytical framework is applied to a realistic bridge. The results show that the reliability index of the flexural-shear coupling evaluation is lower than that of the flexural or shear evaluation, which highlights the importance of the flexural-shear performance checking in the reliability assessment of bridges under random traffic loading. The proposed analytical framework could be further applied to the probabilistic assessment of bridge components subjected to combined loading mechanisms under random loadings
Mechanical properties of seawater volcanic scoria aggregate concrete-filled circular GFRP and stainless steel tubes under axial compression
In this study, the properties of seawater volcanic scoria aggregate concrete (SVAC)-filled circular stainless steel (SFCST) and glass fibre-reinforced plastic (GFRP) tubes (SFCGT) were investigated. Ten groups were considered and 30 specimens were prepared, including four different parameters: the concrete type (SVAC and ordinary concrete [OC]), outer tube type (GFRP and stainless steel tubes), concrete strength (C30 and C40), and tube thickness (0, 3, and 4 mm). The typical influences of the SVAC and outer tube on the mechanical properties of specimens were then analysed. The research findings show that the strength and ductility of the SFCGT and SFCST are significantly higher than those of plain SVAC. The peak strain and strength enhancement factor of the SFCGT and SFCST increase with an increase in the tube thickness, and the concrete strength has a detrimental impact on the toughness of the specimen. Unlike in the confined OC specimens, a sudden decrease is observed in the stress–strain curves of the SFCGT and SFCST owing to the changes in the deformability of the SVAC. Generally, the strengths of the SFCGT and SFCST specimens are 10.3% lower and 4.1% higher than those of the confined OC specimens, respectively. Finally, analytical models of the strength and stress–strain curves considering the influences of the SVAC and passive confinement were established, and numerical simulations were performed to provide a basis for the practical application of the SFCGT and SFCST
HMNet: Hierarchical Multi-Scale Brain Tumor Segmentation Network
An accurate and efficient automatic brain tumor segmentation algorithm is important for clinical practice. In recent years, there has been much interest in automatic segmentation algorithms that use convolutional neural networks. In this paper, we propose a novel hierarchical multi-scale segmentation network (HMNet), which contains a high-resolution branch and parallel multi-resolution branches. The high-resolution branch can keep track of the brain tumor’s spatial details, and the multi-resolution feature exchange and fusion allow the network’s receptive fields to adapt to brain tumors of different shapes and sizes. In particular, to overcome the large computational overhead caused by expensive 3D convolution, we propose a lightweight conditional channel weighting block to reduce GPU memory and improve the efficiency of HMNet. We also propose a lightweight multi-resolution feature fusion (LMRF) module to further reduce model complexity and reduce the redundancy of the feature maps. We run tests on the BraTS 2020 dataset to determine how well the proposed network would work. The dice similarity coefficients of HMNet for ET, WT, and TC are 0.781, 0.901, and 0.823, respectively. Many comparative experiments on the BraTS 2020 dataset and other two datasets show that our proposed HMNet has achieved satisfactory performance compared with the SOTA approaches
Hydrogen Sulfide Promotes Cardiomyocyte Proliferation and Heart Regeneration via ROS Scavenging
Neonatal mouse hearts can regenerate completely in 21 days after cardiac injury, providing an ideal model to exploring heart regenerative therapeutic targets. The oxidative damage by Reactive Oxygen Species (ROS) is one of the critical reasons for the cell cycle arrest of cardiomyocytes (CMs), which cause mouse hearts losing the capacity to regenerate in 7 days or shorter after birth. As an antioxidant, hydrogen sulfide (H2S) plays a protective role in a variety of diseases by scavenging ROS produced during the pathological processes. In this study, we found that blocking H2S synthesis by PAG (H2S synthase inhibitor) suspended heart regeneration and CM proliferation with ROS deposition increase after cardiac injury (myocardial infarction or apex resection) in 2-day-old mice. NaHS (a H2S donor) administration improved heart regeneration with CM proliferation and ROS elimination after myocardial infarction in 7-day-old mice. NaHS protected primary neonatal mouse CMs from H2O2-induced apoptosis and promoted CM proliferation via SOD2-dependent ROS scavenging. The oxidative DNA damage in CMs was reduced with the elimination of ROS by H2S. Our results demonstrated for the first time that H2S promotes heart regeneration and identified NaHS as a potent modulator for cardiac repair
In vitro and in vivo efficacy of a Rift Valley fever virus vaccine based on pseudovirus
Rift Valley fever virus (RVFV), a recognized category A priority pathogen, causes large outbreaks of Rift Valley fever with some fatalities in humans in humans and huge economic losses in livestock. As wild-type RVFV must be handled in BSL-3 or BSL-4 laboratories, we constructed a high-titer vesicular stomatitis virus (VSV) pseudotype bearing RVFV envelope glycoproteins to detect neutralizing antibodies in vitro under BSL-2 conditions. The neutralizing properties of 39 amino acid mutant sites that have occurred naturally over time in the RVFV envelope glycoproteins were analyzed with their corresponding pseudoviral mutants separately. Compared with the results in the primary strain, the variants showed no statistically significant differences. We next established a Balb/c mouse pseudovirus infection model for detecting neutralizing antibodies against pseudovirus. Five immunizations with pseudoviral DNA protected the mice from infection with the pseudovirus. Bioluminescence imaging, which we used to evaluate viral dissemination and distribution in the mice, showed a good relationship between the neutralizing antibodies titers in vitro. These pseudovirus methods will allow for the safe determination of neutralizing antibodies in vivo and in vitro, and will assist with studies on vaccines and drugs against RVFV with the long term objective of Rift Valley fever prevention
Development of a Dew/Frost Point Temperature Sensor Based on Tunable Diode Laser Absorption Spectroscopy and Its Application in a Cryogenic Wind Tunnel
We have proposed a sensor for real-time and online measurement of dew/frost point temperature using tunable diode laser absorption spectroscopy (TDLAS) technique. Initial experiments have demonstrated its feasibility and technical advantages in comparison to a chilled mirror hygrometer (CMH). The TDLAS sensor we developed has a dew/frost point temperature range from −93 °C to + 14.5 °C, with a measurement uncertainly of less than 2%, and a response time of about 0.8 s, which is much faster than that of the chilled mirror hygrometer (ranging from several minutes to several hours). A TDLAS-based dew/frost point sensor has many advantages, such as rapid and continuous measurements, low frost point temperature sensing, high accuracy, and non-intrusiveness. Such a sensor would be useful for dew/frost point temperature determinations in various applications. In a cryogenic wind tunnel, real-time dew/frost point temperature measurements are helpful in preventing the formation of condensed liquid and ice, which can affect the model geometry and lead to unreliable test data