The Hydrogen Bonding in the Hard Domains of the Siloxane Polyurea Copolymer Elastomers.

For probing the structure-property relationships of the polyurea elastomers, we synthesize the siloxane polyurea copolymer elastomer by using two aminopropyl-terminated polysiloxane monomers with low and high number-average molecular weight (Mn), i.e., L-30D and H-130D. To study the influence of the copolymer structures on the film properties, these films are analyzed to obtain the tensile performance, UV-vis spectra, cross-sectional topographies, and glass transition temperature (Tg). The two synthetic thermoplastic elastomer films are characterized by transparency, ductility, and the Tg of the hard domains, depending on the reacting compositions. Furthermore, the film elasticity behavior is studied by the strain recovery and cyclic tensile test, and then, the linear fitting of the tensile data is used to describe the film elasticity based on the Mooney-Rivlin model. Moreover, the temperature-dependent infrared (IR) spectra during heating and cooling are conducted to study the strength and recovery rate of the hydrogen bonding, respectively, and their influence on the film performance is further analyzed; the calculated Mn of the hard segment chains is correlated to the macroscopic recovery rate of the hydrogen bonding. These results can add deep insight to the structure-property relationships of the siloxane polyurea copolymer.

Gait Characteristics and Deviation Factors of Backward Walking in Patients With Chronic Ankle Instability.

BACKGROUND: Despite growing applications of backward walking (BW) in assessing and rehabilitating neuromuscular conditions, its effects on gait in chronic ankle instability (CAI) remain unclear. Moreover, linking patient-reported and clinically generated measures is imperative for understanding CAI. HYPOTHESES: Patients with CAI will exhibit worse and compensatory spatio-temporal and kinetic gait parameters during BW, and patient-reported outcomes (PROs) will be correlated significantly with gait parameters. STUDY DESIGN: Case-control study. LEVEL OF EVIDENCE: Level 4. METHODS: A total of 46 volunteers participated (23 per group). Patients filled out scales for pain, functions, and fear-avoidance beliefs before testing. All participants walked 6 times each in both forward and backward conditions, and gait was recorded using the Win-Track system. A 2-way mixed analysis of variance was performed to compare gait parameters. The relationship between PRO and gait outcomes was assessed through the Pearson product correlation coefficient. RESULTS: The CAI group demonstrated prolonged support and swing phases, increased walk-off angle, and plantar pressure area, but decreased step length and plantar pressure versus controls (P < 0.05). The CAI group had a smaller right walk-off angle during BW than FW; the control group showed the opposite (P < 0.05). The left single stance duration was greater in the CAI group, while the right was not (P < 0.05). PRO correlated significantly with gait parameters, particularly spatial parameters (P < 0.05). CONCLUSION: The CAI group exhibited worse gait parameters during BW. The CAI group exhibited a characteristic compensatory gait pattern. Linking the self-reported scores provides a better representation of gait changes in CAI. CLINICAL RELEVANCE: These results suggest that BW may be an effective strategy for identifying and evaluating CAI. It may be feasible to apply BW to the rehabilitation of CAI.

Recent advances in Scutellariae radix: A comprehensive review on ethnobotanical uses, processing, phytochemistry, pharmacological effects, quality control and influence factors of biosynthesis.

Background: Scutellariae radix (SR) is the dried root of Scutellaria baicalensis Georgi. It has a long history of ethnic medicinal use, traditionally recognized for its efficacy in clearing heat， drying dampness, eliminating fire， removing toxins , stopping bleeding and tranquilizing fetus to prevent miscarriage. Clinically, it is used to treat cold, fever, migraine, hand-foot-and-mouth diseases, liver cancer and inflammatory diseases. Purpose: The review aims to provide a comprehensive reference on the ethnobotanical uses, processing, phytochemistry, pharmacological effect, quality control and influence factors of biosynthesis for a deeper understanding of SR. Results and conclusion: A total of 210 isolated components have been reported in the literature, including flavonoids and their glycosides, phenylpropanoids, phenylethanoid glycosides, phenolic acids, volatile components, polysaccharides and others. The extract of SR and its main flavonoids such as baicalin, baicalein, wogonin, wogonoside, and scutellarin showed antioxidant, anti-inflammatory, anti-tumor, antiviral, hepatoprotective, and neuroprotective effects. However, further studies are required to elucidate its mechanisms of action and clinical applications. The pharmacodynamic evaluation based on traditional efficacy should be conducted. Although various analytical methods have been established for the quality control of SR, there are gaps in the research regarding efficacy-related quality markers and the development of quality control standards for its processed products. The regulatory mechanisms of flavonoids biosynthesis remain to be explored while the influence of environmental and transcription factors on the biosynthesis have been studied. In conclusion, SR is a promising herbal medicine with significant potential for future development.

Structural insights into transcription activation of the Streptomyces antibiotic regulatory protein, AfsR.

The Streptomyces antibiotic regulatory proteins (SARPs) are ubiquitously distributed transcription activators in Streptomyces and control antibiotics biosynthesis and morphological differentiation. However, the molecular mechanism behind SARP-dependent transcription initiation remains elusive. We here solve the cryo-EM structure of an AfsR-loading RNA polymerase (RNAP)-promoter intermediate complex (AfsR-RPi) including the Streptomyces coelicolor RNAP, a large SARP member AfsR, and its target promoter DNA that retains the upstream portion straight. The structure reveals that one dimeric N-terminal AfsR-SARP domain (AfsR-SARP) specifically engages with the same face of the AfsR-binding sites by the conserved DNA-binding domains (DBDs), replacing σHrdBR4 to bind the suboptimal -35 element, and shortens the spacer between the -10 and -35 elements. Notably, the AfsR-SARPs also recruit RNAP through extensively interacting with its conserved domains (ß flap, σHrdBR4, and αCTD). Thus, these macromolecular snapshots support a general model and provide valuable clues for SARP-dependent transcription activation in Streptomyces.

Force-enhanced sensitive and specific detection of DNA-intercalative agents directly from microorganisms at single-molecule level.

Microorganisms can produce a vast array of bioactive secondary metabolites, including DNA-intercalating agents like actinomycin D, doxorubicin, which hold great potential for cancer chemotherapy. However, discovering novel DNA-intercalating compounds remains challenging due to the limited sensitivity and specificity of conventional activity assays, which require large-scale fermentation and purification. Here, we introduced the single-molecule stretching assay (SMSA) directly to microbial cultures or extracts for discovering DNA-intercalating agents, even in trace amounts of microbial cultures (5 µl). We showed that the unique changes of dsDNA in contour length and overstretching transition enable the specific detection of intercalators from complex samples without the need for extensive purification. Applying force to dsDNA also enhanced the sensitivity by increasing both the binding affinity Ka and the quantity of ligands intercalation, thus allowing the detection of weak intercalators, which are often overlooked using traditional methods. We demonstrated the effectiveness of SMSA, identified two DNA intercalator-producing strains: Streptomyces tanashiensis and Talaromyces funiculosus, and isolated three DNA intercalators: medermycin, kalafungin and ligustrone B. Interestingly, both medermycin and kalafungin, classified as weak DNA intercalators (Ka ∼103 M-1), exhibited potent anti-cancer activity against HCT-116 cancer cells, with IC50 values of 52 ± 6 and 70 ± 7 nM, respectively.

A Saccharomyces boulardii-derived antioxidant protein, thioredoxin, ameliorates intestinal inflammation through transactivating epidermal growth factor receptor.

Saccharomyces boulardii (Sb) is a probiotic yeast for the treatment of gastrointestinal disorders, including inflammatory bowel disease (IBD). Little is known about the modulatory capacity of the Sb in IBD. Here, we found that oral gavage of Sb supernatant (SbS) alleviated gut inflammation, protected the intestinal barrier, and reversed DSS-induced down-regulated activation of epidermal growth factor receptor (EGFR) in colitis. Mass spectrum analysis showed that thioredoxin (Trx) is one of the critical secreted soluble proteins participating in EGFR activation detected in SbS. Trx exerted an array of significant effects on anti-inflammatory activity, including alleviating inflammation, protecting gut barrier, suppressing apoptosis, as well as reducing oxidative stress. Mechanistically, Trx promoted EGFR ligand gene expression and transactivated EGFR in a concentration-dependent manner. EGFR kinase inhibitor could block Trx-mediated preventive effects of intestinal epithelial injury. Our data suggested that Sb-derived soluble protein Trx could serve as a potential prophylactic, as a novel postbiotic against colitis, which provides a new strategy for the precision prevention and treatment of IBD.

Dominant activities of fear engram cells in the dorsal dentate gyrus underlie fear generalization in mice.

Over-generalized fear is a maladaptive response to harmless stimuli or situations characteristic of posttraumatic stress disorder (PTSD) and other anxiety disorders. The dorsal dentate gyrus (dDG) contains engram cells that play a crucial role in accurate memory retrieval. However, the coordination mechanism of neuronal subpopulations within the dDG network during fear generalization is not well understood. Here, with the Tet-off system combined with immunostaining and two-photon calcium imaging, we report that dDG fear engram cells labeled in the conditioned context constitutes a significantly higher proportion of dDG neurons activated in a similar context where mice show generalized fear. The activation of these dDG fear engram cells encoding the conditioned context is both sufficient and necessary for inducing fear generalization in the similar context. Activities of mossy cells in the ventral dentate gyrus (vMCs) are significantly suppressed in mice showing fear generalization in a similar context, and activating the vMCs-dDG pathway suppresses generalized but not conditioned fear. Finally, modifying fear memory engrams in the dDG with "safety" signals effectively rescues fear generalization. These findings reveal that the competitive advantage of dDG engram cells underlies fear generalization, which can be rescued by activating the vMCs-dDG pathway or modifying fear memory engrams, and provide novel insights into the dDG network as the neuronal basis of fear generalization.

Carvedilol to prevent decompensation of cirrhosis in patients with clinically significant portal hypertension stratified by liver stiffness: study protocol for a randomied, double-blind, placebo-controlled, multicentre trial in China.

INTRODUCTION: Patients with clinically significant portal hypertension (CSPH) are recommended to be treated with non-selective beta-blockers (ie, carvedilol) to prevent the first hepatic decompensation event by the renewing Baveno VII consensus. CSPH is defined by hepatic venous pressure gradient (HVPG)≥10 mm Hg; however, the HVPG measurement is not widely adopted due to its invasiveness. Liver stiffness (LS)≥25 kPa can be used as a surrogate of HVPG≥10 mm Hg to rule in CSPH with 90% of the positive predicting value in majority aetiologies of patients. A compelling argument is existing for using LS≥25 kPa to diagnose CSPH and then to initiate carvedilol in patients with compensated cirrhosis, and about 5%-6% of patients under this diagnosis criteria may not be benefited from carvedilol and are at risk of lower heart rate and mean arterial pressure. Randomised controlled trial on the use of carvedilol to prevent liver decompensation in CSPH diagnosed by LS remains to elucidate. Therefore, we aimed to investigate if compensated cirrhosis patients with LS≥25 kPa may benefit from carvedilol therapy. METHODS AND ANALYSIS: This study is a randomised, double-blind, placebo-controlled, multicentre trial. We will randomly assign 446 adult compensated cirrhosis patients with LS≥25 kPa and without any previous decompensated event and without high-risk gastro-oesophageal varices. Patients are randomly divided into two groups, with 223 subjects in group A and 223 subjects in group B. Group A is a carvedilol intervention group, while group B is a placebo group. All patients in both groups will receive aetiology therapies and are followed up at an interval of 6 months. The 3-year incidences of decompensated events of cirrhosis-related and liver-related death are the primary outcome. The secondary outcomes include development of each complication of portal hypertension individually (ascites, variceal bleeding or overt hepatic encephalopathy), development of spontaneous bacterial peritonitis and other bacterial infections, development of new varices, growth of small varices to large varices, delta changes in LS and spleen stiffness, change in hepatic dysfunction assessed by Child-Pugh and model for end-stage liver disease score, change in platelet count, development of hepatocellular carcinoma, development of portal vein thrombosis and adverse events with a 3-year follow-up. A predefined interim analysis will be performed to ensure that the calculation is reasonable. ETHICS AND DISSEMINATION: The study protocol has been approved by the ethics committees of the Sixth People's Hospital of Shenyang (2023-05-003-01) and independent ethics committee for clinical research of Zhongda Hospital, affiliated to Southeast University (2023ZDSYLL433-P01). The results from this trial will be submitted for publication in peer-reviewed journals and will be presented at international conferences. TRIAL REGISTRATION NUMBER: ChiCTR2300073864.

Hsa_circ_0001359 in Serum Exosomes: A Promising Marker to Predict Bronchopulmonary Dysplasia in Premature Infants.

Objective: This prospective study is to explore the role of specific circRNAs in predicting the development of bronchopulmonary dysplasia (BPD). Methods: From July 1, 2021 to December 1, 2021, peripheral blood samples were collected from 62 premature infants with gestational age (GA) ≤32 weeks on the 7th, 14th, and 28th day after birth. Then, on the 28th day, the included infants were divided into the BPD group and the non-BPD group according to the definition of BPD. Serum exosomal circRNAs from peripheral blood were identified, sequenced, and compared between the BPD and non-BPD groups at different time points. Specific differentially expressed circRNAs were further verified from another 42 enrolled premature infants (GA ≤32 weeks). The classical lung biological markers in serum were also measured simultaneously. Results: Hsa_circ_0001359 in serum exosomes showed continuous differential expression between the BPD group and the non-BPD group on the 7th, 14th, and 28th day. Compared with that, classical lung biological markers like IL-6, IL-33, KL-6, and ET-1 did not exhibit continuous differences. Moreover, the expression of hsa_circ_0001359 on day 7 had a higher predictive value in predicting BPD (area under curve:0.853, 95% CI:0.738-0.968; adjusted odds ratio:6.033, 95% CI:2.373-13.326). The calibration curve further showed the mean absolute error = 0.033, mean squared error = 0.00231, and quantile of absolute error = 0.058. Conclusion: Hsa_circ_0001359 in serum exosomes is a promising marker for predicting BPD in preterm infants with gestational age ≤32 weeks.

A dynamically cross-linked catechol-grafted chitosan/gelatin hydrogel dressing synergised with photothermal therapy and baicalin reduces wound infection and accelerates wound healing.

Superior multifunctional hydrogel dressings are of considerable interest in wound healing. In clinical practice, it is useful to investigate hydrogel dressings that offer multifunctional benefits to expedite the process of wound healing. In this study, Catechol-grafted Chitosan, Gelatin, and Fe3+ as substrates to construct a hydrogel network. The network was dynamically cross-linked to form Ccg@Fe hydrogel substrate. Fe3O4 nanoparticles and baicalin, which possess antimicrobial and anti-inflammatory properties, were loaded onto the substrate to form a photothermal antibacterial composite hydrogel dressing (Ccg@Fe/Bai@Fe3O4 NPs). The Ccg@Fe hydrogel was characterised using Fourier transform infrared spectroscopy (FTIR) and Ultraviolet-visible spectrophotometry (UV-Vis). The morphological, mechanical, and adhesion properties of the hydrogel were determined using scanning electron microscopy (SEM) and a universal testing machine. The hydrogel's swelling, hemostasis, and self-healing properties were also evaluated. Additionally, the study determined the release rate of hydrogel-loaded antimicrobial and anti-inflammatory Baicalin (Ccg@Fe/Bai) and evaluated the photothermal antimicrobial properties of hydrogel-loaded Fe3O4 nanoparticles (Ccg@Fe/Bai@Fe3O4 NPs) through synergistic photothermal therapy (PTT). Histological staining of mice skin wound tissues using Masson and H&E revealed that the Ccg@Fe/Bai@Fe3O4 NPs hydrogel dressing demonstrated potential healing ability with the aid of PTT. The study suggests that this multifunctional hydrogel dressing has great potential for wound healing.

Two-stage sparse multi-objective evolutionary algorithm for channel selection optimization in BCIs.

Background: Channel selection has become the pivotal issue affecting the widespread application of non-invasive brain-computer interface systems in the real world. However, constructing suitable multi-objective problem models alongside effective search strategies stands out as a critical factor that impacts the performance of multi-objective channel selection algorithms. This paper presents a two-stage sparse multi-objective evolutionary algorithm (TS-MOEA) to address channel selection problems in brain-computer interface systems. Methods: In TS-MOEA, a two-stage framework, which consists of the early and late stages, is adopted to prevent the algorithm from stagnating. Furthermore, The two stages concentrate on different multi-objective problem models, thereby balancing convergence and population diversity in TS-MOEA. Inspired by the sparsity of the correlation matrix of channels, a sparse initialization operator, which uses a domain-knowledge-based score assignment strategy for decision variables, is introduced to generate the initial population. Moreover, a Score-based mutation operator is utilized to enhance the search efficiency of TS-MOEA. Results: The performance of TS-MOEA and five other state-of-the-art multi-objective algorithms has been evaluated using a 62-channel EEG-based brain-computer interface system for fatigue detection tasks, and the results demonstrated the effectiveness of TS-MOEA. Conclusion: The proposed two-stage framework can help TS-MOEA escape stagnation and facilitate a balance between diversity and convergence. Integrating the sparsity of the correlation matrix of channels and the problem-domain knowledge can effectively reduce the computational complexity of TS-MOEA while enhancing its optimization efficiency.

Field cabbage detection and positioning system based on improved YOLOv8n.

BACKGROUND: Pesticide efficacy directly affects crop yield and quality, making targeted spraying a more environmentally friendly and effective method of pesticide application. Common targeted cabbage spraying methods often involve object detection networks. However, complex natural and lighting conditions pose challenges in the accurate detection and positioning of cabbage. RESULTS: In this study, a cabbage detection algorithm based on the YOLOv8n neural network (YOLOv8-cabbage) combined with a positioning system constructed using a Realsense depth camera is proposed. Initially, four of the currently available high-performance object detection models were compared, and YOLOv8n was selected as the transfer learning model for field cabbage detection. Data augmentation and expansion methods were applied to extensively train the model, a large kernel convolution method was proposed to improve the bottleneck section, the Swin transformer module was combined with the convolutional neural network (CNN) to expand the perceptual field of feature extraction and improve edge detection effectiveness, and a nonlocal attention mechanism was added to enhance feature extraction. Ablation experiments were conducted on the same dataset under the same experimental conditions, and the improved model increased the mean average precision (mAP) from 88.8% to 93.9%. Subsequently, depth maps and colour maps were aligned pixelwise to obtain the three-dimensional coordinates of the cabbages via coordinate system conversion. The positioning error of the three-dimensional coordinate cabbage identification and positioning system was (11.2 mm, 10.225 mm, 25.3 mm), which meets the usage requirements. CONCLUSIONS: We have achieved accurate cabbage positioning. The object detection system proposed here can detect cabbage in real time in complex field environments, providing technical support for targeted spraying applications and positioning.

Clinical Study of a Four-Step Program for the Treatment of Plantar Fasciitis with Bone Spurs.

OBJECTIVE: The most common causes of plantar and heel pain are plantar fasciitis and calcaneal spurs, and they often co-exist. Surgery is a recognized treatment for refractory plantar fasciitis. However, few studies have proposed treatment options for patients with metatarsophalangeal fasciitis with bone spurs. Accordingly, this study's purpose was to propose a four-step surgical regimen, and to improve the surgical outcome of plantar fasciitis with osteophytes and to establish a procedure for surgical treatment. METHODS: Retrospective analysis of 45 patients suffering from plantar fasciitis with bone spurs from 2020 to 2023. All patients underwent a four-step procedure, including plantar fascia release, calcaneal spur grinding, inflammatory tissue removal, and calcaneal burr decompression. The imaging parameters and functional scores were recorded before and after the operation. The objective evaluation included the measurement of calcaneal spur length on radiographs. Clinical evaluation included the American Orthopaedic Foot and Ankle Society (AOFAS), the Visual Analog Scale (VAS), and the Foot and Ankle Outcome Scale (FAOS). Measurement data that conformed to normal distribution were expressed as (x2 ± s), and pre-and postoperative AOFAS, FAOS, and VAS scores were compared using repeated-measures ANOVA, and preoperative and postoperative spur lengths were compared using paired t-tests. RESULTS: The 45 patients were followed up for 3 to 30 months, (17.72 ± 8.53) months, at final follow-up, the patient's AOFAS score improved from preoperative (74.93 ± 5.56) to (94.78 ± 3.98), FAOS score increased from preoperative (76.42 ± 3.37) to (96.16 ± 2.74), the VAS score decreased from (3.18 ± 0.54) to (1.07 ± 1.20) (p < 0.05), the length of spur decreased from (0.72 ± 1.81) cm to (0.23 ± 1.19) cm, and there were significant differences before and after operation (p < 0.05). CONCLUSION: The four-step surgical regimen is an appropriate and effective surgical procedure to treat plantar fasciitis with bone spurs.

A 5-Hydroxymethylcytosine-Based Noninvasive Model for Early Detection of Colorectal Carcinomas and Advanced Adenomas: The METHOD-2 Study.

PURPOSE: Detection of colorectal carcinomas at a time when there are more treatment options is associated with better outcomes. This prospective case-control study assessed the 5-hydroxymethylcytosine (5hmC) biomarkers in circulating cell-free DNA (cfDNA) for early detection of colorectal carcinoma and advanced adenomas (AA). EXPERIMENTAL DESIGN: Plasma cfDNA samples from 2,576 study participants from the multicenter METHOD-2 study (NCT03676075) were collected, comprising patients with newly diagnosed colorectal carcinoma (n = 1,074), AA (n = 356), other solid tumors (n = 80), and non-colorectal carcinoma/AA controls (n = 1,066), followed by genome-wide 5hmC profiling using the 5hmC-Seal technique and the next-generation sequencing. A weighted diagnostic model for colorectal carcinoma (stage I-III) and AA was developed using the elastic net regularization in a discovery set and validated in independent samples. RESULTS: Distribution of 5hmC in cfDNA reflected gene regulatory relevance and tissue of origin. Besides being confirmed in internal validation, a 96-gene model achieved an area under the curve (AUC) of 90.7% for distinguishing stage I-III colorectal carcinoma from controls in 321 samples from multiple centers for external validation, regardless of primary location or mutation status. This model also showed cancer-type specificity as well as high capacity for distinguishing AA from controls with an AUC of 78.6%. Functionally, differential 5hmC features associated with colorectal carcinoma and AA demonstrated relevance to colorectal carcinoma biology, including pathways such as calcium and MAPK signaling. CONCLUSIONS: Genome-wide mapping of 5hmC in cfDNA shows promise as a highly sensitive and specific noninvasive blood test to be integrated into screening programs for improving early detection of colorectal carcinoma and high-risk AA.

Structural and functional insights into transcription activation of the essential LysR-type transcriptional regulators.

The enormous LysR-type transcriptional regulators (LTTRs), which are diversely distributed amongst prokaryotes, play crucial roles in transcription regulation of genes involved in basic metabolic pathways, virulence and stress resistance. However, the precise transcription activation mechanism of these genes by LTTRs remains to be explored. Here, we determine the cryo-EM structure of a LTTR-dependent transcription activation complex comprising of Escherichia coli RNA polymerase (RNAP), an essential LTTR protein GcvA and its cognate promoter DNA. Structural analysis shows two N-terminal DNA binding domains of GcvA (GcvA_DBD) dimerize and engage the GcvA activation binding sites, presenting the -35 element for specific recognition with the conserved σ70R4. In particular, the versatile C-terminal domain of α subunit of RNAP directly interconnects with GcvA_DBD, σ70R4 and promoter DNA, providing more interfaces for stabilizing the complex. Moreover, molecular docking supports glycine as one potential inducer of GcvA, and single molecule photobleaching experiments kinetically visualize the occurrence of tetrameric GcvA-engaged transcription activation complex as suggested for the other LTTR homologs. Thus, a general model for tetrameric LTTR-dependent transcription activation is proposed. These findings will provide new structural and functional insights into transcription activation of the essential LTTRs.

Magnitude and determinants of excess total, age-specific and sex-specific all-cause mortality in 24 countries worldwide during 2020 and 2021: results on the impact of the COVID-19 pandemic from the C-MOR project.

INTRODUCTION: To examine the impact of the COVID-19 pandemic on mortality, we estimated excess all-cause mortality in 24 countries for 2020 and 2021, overall and stratified by sex and age. METHODS: Total, age-specific and sex-specific weekly all-cause mortality was collected for 2015-2021 and excess mortality for 2020 and 2021 was calculated by comparing weekly 2020 and 2021 age-standardised mortality rates against expected mortality, estimated based on historical data (2015-2019), accounting for seasonality, and long-term and short-term trends. Age-specific weekly excess mortality was similarly calculated using crude mortality rates. The association of country and pandemic-related variables with excess mortality was investigated using simple and multilevel regression models. RESULTS: Excess cumulative mortality for both 2020 and 2021 was found in Austria, Brazil, Belgium, Cyprus, England and Wales, Estonia, France, Georgia, Greece, Israel, Italy, Kazakhstan, Mauritius, Northern Ireland, Norway, Peru, Poland, Slovenia, Spain, Sweden, Ukraine, and the USA. Australia and Denmark experienced excess mortality only in 2021. Mauritius demonstrated a statistically significant decrease in all-cause mortality during both years. Weekly incidence of COVID-19 was significantly positively associated with excess mortality for both years, but the positive association was attenuated in 2021 as percentage of the population fully vaccinated increased. Stringency index of control measures was positively and negatively associated with excess mortality in 2020 and 2021, respectively. CONCLUSION: This study provides evidence of substantial excess mortality in most countries investigated during the first 2 years of the pandemic and suggests that COVID-19 incidence, stringency of control measures and vaccination rates interacted in determining the magnitude of excess mortality.

Saikosaponin a promotes neutrophil extracellular trap formation and bactericidal activity.

This study aimed to investigate the effects of SSa, one of the major triterpenoid saponins extracted from Radix bupleuri, on neutrophil extracellular trap (NET) formation and the mechanism associated with this process. Using Sytox green and immunofluorescence assays, we found SSa rapidly induced NET formation, which depended on NADPH oxidase (NOX)-independent ROS production and autophagy. Pharmacologic inhibitor studies indicated that ERK and PI3K/AKT signalling were also required for SSa-induced NET formation, whereas protein arginine deiminase 4 (PAD4) was not required. Furthermore, we found that SSa promoted neutrophil bactericidal activity mainly through NET formation. Based on flow cytometry and the Cell Counting Kit-8 (CCK-8) assays, the results demonstrated that SSa-induced NET formation occurred without neutrophil death. Taken together, these findings indicated that SSa could be a potential natural product to boost innate immune defense against pathogen attack via NET formation.