Structural insights into the biosynthetic mechanism of Nα-GlyT and 5-NmdU hypermodifications of DNA.

DNA hypermodifications are effective weapons for phages to cope with the defense system of bacteria. The biogenesis of DNA hypermodification in phages involves multiple steps, from the modified deoxynucleotide monophosphates to the final hypermodification on the DNA chains. PseudomonasPaMx11 gp46 and gp47 encode the enzymes for sequentially converting 5-phosphomethyl-2'-deoxyuridine to 5-Nα-glycinylthymidine and 5-aminomethyl-2'-deoxyuridine. Here, we have determined the crystal structures of gp46 and gp47 in their apo and double-stranded DNA (dsDNA)-bound forms. We uncovered their dsDNA recognition properties and identified the critical residues for the catalytic reactions. Combined with in vitro biochemical studies, we proposed a plausible reaction scheme for gp46 and gp47 in converting these DNA hypermodifications. Our studies will provide the structural basis for future bioengineering of the synthetic pathway of hypermodification and identifying new modifications in mammals by enzyme-assisted sequencing methods.

Design of a sorbitol-activated nitrogen metabolism-dependent regulatory system for redirection of carbon metabolism flow in Bacillus licheniformis.

Synthetic regulation of metabolic fluxes has emerged as a common strategy to improve the performance of microbial cell factories. The present regulatory toolboxes predominantly rely on the control and manipulation of carbon pathways. Nitrogen is an essential nutrient that plays a vital role in growth and metabolism. However, the availability of broadly applicable tools based on nitrogen pathways for metabolic regulation remains limited. In this work, we present a novel regulatory system that harnesses signals associated with nitrogen metabolism to redirect excess carbon flux in Bacillus licheniformis. By engineering the native transcription factor GlnR and incorporating a sorbitol-responsive element, we achieved a remarkable 99% inhibition of the expression of the green fluorescent protein reporter gene. Leveraging this system, we identified the optimal redirection point for the overflow carbon flux, resulting in a substantial 79.5% reduction in acetoin accumulation and a 2.6-fold increase in acetate production. This work highlight the significance of nitrogen metabolism in synthetic biology and its valuable contribution to metabolic engineering. Furthermore, our work paves the way for multidimensional metabolic regulation in future synthetic biology endeavors.

LncRNA DYNLRB2-AS1 promotes gemcitabine resistance of nasopharyngeal carcinoma by inhibiting the ubiquitination degradation of DHX9 protein.

Gemcitabine (GEM) based induction chemotherapy is a standard treatment for locoregionally advanced nasopharyngeal carcinoma (NPC). However, approximately 15 % of patients are still resistant to GEM-containing chemotherapy, which leads to treatment failure. Nevertheless, the underlying mechanisms of GEM resistance remain poorly understood. Herein, based on a microarray analysis, we identified 221 dysregulated lncRNAs, of which, DYNLRB2-AS1 was one of the most upregulated lncRNAs in GEM-resistance NPC cell lines. DYNLRB2-AS1 was shown to function as contain an oncogenic lncRNA that promoted NPC GEM resistance, cell proliferation, but inhibited cell apoptosis. Mechanistically, DYNLRB2-AS1 could directly bind to the DHX9 protein and prevent its interaction with the E3 ubiquitin ligase PRPF19, and thus blocking PRPF19-mediated DHX9 degradation, which ultimately facilitated the repair of DNA damage in the presence of GEM. Clinically, higher DYNLRB2-AS1 expression indicated an unfavourable overall survival of NPC patients who received induction chemotherapy. Overall, this study identified the oncogenic lncRNA DYNLRB2-AS1 as an independent prognostic biomarker for patients with locally advanced NPC and as a potential therapeutic target for overcoming GEM chemoresistance in NPC.

Widespread slow oscillations support interictal epileptiform discharge networks in focal epilepsy.

Interictal epileptiform discharges (IEDs) often co-occur across spatially-separated cortical regions, forming IED networks. However, the factors prompting IED propagation remain unelucidated. We hypothesized that slow oscillations (SOs) might facilitate IED propagation. Here, the amplitude and phase synchronization of SOs preceding propagating and non-propagating IEDs were compared in 22 patients with focal epilepsy undergoing intracranial electroencephalography (EEG) evaluation. Intracranial channels were categorized into the irritative zone (IZ) and normal zone (NOZ) regarding the presence of IEDs. During wakefulness, we found that pre-IED SOs within the IZ exhibited higher amplitudes for propagating IEDs than non-propagating IEDs (delta band: p = 0.001, theta band: p < 0.001). This increase in SOs was also concurrently observed in the NOZ (delta band: p = 0.04). Similarly, the inter-channel phase synchronization of SOs prior to propagating IEDs was higher than those preceding non-propagating IEDs in the IZ (delta band: p = 0.04). Through sliding window analysis, we observed that SOs preceding propagating IEDs progressively increased in amplitude and phase synchronization, while those preceding non-propagating IEDs remained relatively stable. Significant differences in amplitude occurred approximately 1150 ms before IEDs. During non-rapid eye movement (NREM) sleep, SOs on scalp recordings also showed higher amplitudes before intracranial propagating IEDs than before non-propagating IEDs (delta band: p = 0.006). Furthermore, the analysis of IED density around sleep SOs revealed that only high-amplitude sleep SOs demonstrated correlation with IED propagation. Overall, our study highlights that transient but widely distributed SOs are associated with IED propagation as well as generation in focal epilepsy during sleep and wakefulness, providing new insight into the EEG substrate supporting IED networks.

ECM stiffness affects cargo sorting into MSC-EVs to regulate their secretion and uptake behaviors.

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have garnered extensive attention as natural product-based nanomedicines and potential drug delivery vehicles. However, the specific mechanism for regulating MSC-EVs secretion and delivery remains unclear. Here, we demonstrate that extracellular matrix (ECM) stiffness regulates the secretion and delivery of EVs by affecting MSCs' cargo sorting mechanically. Using multi-omics analysis, we found that a decrease in ECM stiffness impeded the sorting of vesicular transport-related proteins and autophagy-related lipids into MSC-EVs, impairing their secretion and subsequent uptake by macrophages. Hence, MSC-EVs with different secretion and uptake behaviors can be produced by changing the stiffness of culture substrates. This study provides new insights into MSC-EV biology and establishes a connection between MSC-EV behaviors and ECM from a biophysical perspective, providing a basis for the rational design of biomedical materials.

De novo biosynthesis of carminic acid in Saccharomyces cerevisiae.

Carminic acid is a natural red dye extracted from the insect Dactylopius coccus. Due to its ideal dying effect and high safety, it is widely used in food and cosmetics industries. Previous study showed that introduction of polyketide synthase (OKS) from Aloe arborescens, cyclase (ZhuI) and aromatase (ZhuJ) from Streptomyces sp. R1128, and C-glucosyltransferase (UGT2) from D. coccus into Aspergillus nidulans could achieve trace amounts of de novo production. These four genes were introduced into Saccharomyces cerevisiae, but carminic acid was not detected. Analysis of the genome of A. nidulans revealed that 4'-phosphopantetheinyl transferase (NpgA) and monooxygenase (AptC) are essential for de novo biosynthesis of carminic acid in S. cerevisiae. Additionally, endogenous hydroxylase (Cat5) from S. cerevisiae was found to be responsible for hydroxylation of flavokermesic acid to kermesic acid. Therefore, all enzymes and their functions in the biosynthesis of carminic acid were explored and reconstructed in S. cerevisiae. Through systematic pathway engineering, including regulating enzyme expression, enhancing precursor supply, and modifying the ß-oxidation pathway, the carminic acid titer in a 5 L bioreactor reached 7580.9 µg/L, the highest yet reported for a microorganism. Heterologous reconstruction of the carminic acid biosynthetic pathway in S. cerevisiae has great potential for de novo biosynthesis of anthraquinone dye.

Predictors and prevalence of COVID-19 vaccination in patients with focal epilepsy following resection surgery.

BACKGROUND AND PURPOSE: In light of the ongoing COVID-19 pandemic, vaccination has emerged as the primary and most effective solution. The aim of this study was to examine compliance rates of vaccination and explore the factors that predict vaccine uptake among patients with epilepsy (PWE) who have undergone resection surgery. METHOD: To examine the variations in vaccination coverage, safety concerns, and factors influencing vaccination hesitancy among PWE who have undergone resection surgery, this study recruited patients with at least one-year follow-up. We utilized questionnaires to gather clinical characteristics and obtain information regarding COVID-19 vaccines. RESULTS: Among the 303 patients included in the study, a majority of 229 (75.58%) achieved a seizure-free outcome (Engel Ia). Of these patients, 178 (58.75%) received at least one dose of COVID-19 vaccine, and the vaccination rate has remained relatively consistent over the past six months. Nearly 94.95% of those who received the vaccine completed the full vaccination regimen, with the majority (n = 174, 97.75%) opting for an inactivated vaccine. Only three patients reported side effects unrelated to epilepsy, and one patient experienced a worsening of typical aura seizures within one month after vaccination. Notably, significant positive associations were observed between COVID-19 vaccine acceptance and adulthood (age 18 years or older) (OR = 1.820, 95% CI = 1.018-3.252, p = 0.043) as well as achieving a seizure-free outcome (OR = 2.823, 95% CI = 1.619-4.921, p < 0.001). Regarding the unvaccinated patients, approximately one-fifth expressed willingness to receive a future COVID-19 vaccine, while the remainder were hesitant (41.60%) or unsure (39.20%) about vaccination. These reservations mainly stemmed from concerns about the potential worsening of seizures and vaccine safety. CONCLUSIONS: Inactivated vaccines can be considered safe for individuals with epilepsy who have undergone resection surgery. The likelihood of being vaccinated was found to be comparatively higher among the cohort with seizure-free status or adults. To promote COVID-19 vaccination among children, it is crucial to implement comprehensive education and public awareness campaigns that emphasize the safety of vaccines. These efforts will help encourage widespread acceptance of vaccination and ensure the well-being of individuals with epilepsy.

COVID-19 vaccination hesitancy and safety among adult people with epilepsy in eastern China.

OBJECTIVE: This study assesses the hesitancy and safety of vaccination administration for the novel 2019 Coronavirus Disease (COVID-19) among adult people with epilepsy (PWE). METHODS: We recruited adult PWE who visited the outpatient epilepsy clinic from August 2021 to February 2022. We administered a structured questionnaire and a face-to-face interview regarding demographic factors, epilepsy characteristics, and relevant vaccine issues to all patients. Factors related to receiving a vaccine and epilepsy-related events after vaccination were then analyzed. RESULTS: A total of 501 PWE were surveyed; 288 were unvaccinated and 213 were vaccinated. Patients without jobs (OR: 0.59; 95% CI: 0.37-0.95, p = 0.03) were less likely to receive the vaccine compared to students or those with jobs. Other factors associated with vaccination were a higher number of anti-seizure medications (OR: 0.72; 95% CI: 0.55-0.95, p = 0.02) and a lower pre-vaccine seizure frequency (OR: 2.21; 95% CI: 1.06-4.59, p = 0.03). Of the 213 vaccinated patients, 10 (4.70%) reported at least one local and/or systemic side effect. Most patients (92.50%) did not report worse seizures within one month of vaccination. Poor ASM adherence (OR: 15.06; 95% CI: 1.75-129.87, p = 0.01) and fatigue/stimulant drinks such as caffeine (OR: 50.59; 95% CI: 7.57-337.94, p < 0.01) were significantly associated with seizure worsening within one month of receiving the COVID-19 vaccination. CONCLUSION: Almost two-fifths of patients with adult PWE have received a COVID-19 vaccine. Attention should be paid to educating epilepsy patients without jobs on the significance and safety of the vaccine. There was a low risk of seizure worsening in the short term after vaccination in PWE.

NADP(+)-IDH Mutations Promote Hypersuccinylation that Impairs Mitochondria Respiration and Induces Apoptosis Resistance.

Elucidating the tumorigenic mechanism of R-2-hydroxyglutarate (R-2HG) is critical for determining how NADP(+)-IDH mutations cause cancer. Here we report that R-2HG induces cancerous metabolism and apoptosis resistance through promoting hypersuccinylation. By competitive inhibition of the mitochondrial tricarboxylic acid cycle enzyme succinate dehydrogenase (SDH), R-2HG preferentially induced succinyl-CoA accumulation and hypersuccinylation in the mitochondria. IDH1 mutation-bearing glioma samples and cells were hypersuccinylated in the mitochondria. IDH1 mutation or SDH inactivation resulted in hypersuccinylation, causing respiration inhibition and inducing cancerous metabolism and mitochondrial depolarization. These mitochondrial dysfunctions induced BCL-2 accumulation at the mitochondrial membrane, leading to apoptosis resistance of hypersuccinylated cells. Relief of hypersuccinylation by overexpressing the desuccinylase SIRT5 or supplementing glycine rescued mitochondrial dysfunctions, reversed BCL-2 accumulation, and slowed the oncogenic growth of hypersuccinylated IDH1(R132C)-harboring HT1080 cells. Thus, R-2HG-induced hypersuccinylation contributes to the tumorigenicity of NADP(+)-IDH mutations, suggesting the potential of hypersuccinylation inhibition as an intervention for hypersuccinylation-related tumors.

A nomogram prediction of citrate reaction during mononuclear cell collection in solid tumor patients.

PURPOSE: Citrate reaction is one of the main adverse events in peripheral blood mononuclear cell (MNC) collection. The aim of this study was to elucidate the risk factors for citrate reaction in patients with advanced solid tumor collection and to construct a nomogram to predict the risk. METHODS: One hundred forty-eight patients with advanced solid tumor who underwent peripheral blood MNC collection in our hospital between January 2021 to December 2021 were selected. The general data, creatinine level before collection, Ca2+ concentration before collection, absolute value of monocyte lymphocytes before collection, circulating blood volume, anticoagulant dosage, and blood collection duration were included in Logistic regression analysis to identify the risk factors of citrate reaction. According to the results of the multivariate logistic model, nomogram was established and receiver operating characteristic (ROC) curve was drawn to evaluate the predictive value of the model. RESULTS: Among the 148 solid tumor patients, 35 patients (23.6%) of the 148 patients developed citrate reaction. Multivariate analysis showed that the risk factors for citrate reaction in the process of collection included sex (odds ratio [OR] = 6.718; 95% confidence interval [95% CI]: 2.191-20.594, P = .001), age (OR = 0.957; 95% CI: 0.921-0.996, P = .03), and processed circulating blood volume (OR = 1.001; 95% CI: 1.000-1.002, P = .01). Logistic regression can analyze independent risk factors and establish risk prediction model. The predictive performance of the model is good, and the area under ROC curve is 0.799. CONCLUSIONS: The MNC collection process is safe. The incidence of citrate reaction in the collection of peripheral blood MNCs from patients with advanced solid tumor is related to the age, gender, and processed circulating blood volume of patients. The nomogram can be used to assess a patient's risk of citrate reaction.

Photo-Driven Iron-Induced Non-Oxidative Coupling of Methane to Ethane.

Photo-driven CH4 conversion to multi-carbon products and H2 is attractive but challenging, and the development of efficient catalytic systems is critical. Herein, we construct a solar-energy-driven redox cycle for combining CH4 conversion and H2 production using iron ions. A photo-driven iron-induced reaction system was developed, which is efficient at selective coupling of CH4 as well as conversion of benzene and cyclohexane under mild conditions. For CH4 conversion, 94 % C2 selectivity and a C2 H6 formation rate of 8.4 µmol h-1 is achieved. Mechanistic studies reveal that CH4 coupling is induced by hydroxyl radical, which is generated by photo-driven intermolecular charge migration of an Fe3+ complex. The delicate coordination structure of the [Fe(H2 O)5 OH]2+ complex ensures selective C-H bond activation and C-C coupling of CH4 . The produced Fe2+ can be used to reduce the potential for electrolytic H2 production, and then turns back into Fe3+ , forming an energy-saving and sustainable recyclable system.

i-CRISPR: a personalized cancer therapy strategy through cutting cancer-specific mutations.

Developing a strategy to specifically kill cancer cells without inducing obvious damage to normal cells may be of great clinical significance for cancer treatment. In the present study, we developed a new precise personalized strategy named "i-CRISPR" for cancer treatment through adding DNA damage repair inhibitors(i) and inducing cancer cell-specific DNA double strand breaks by CRISPR. Through in vitro and in vivo experiments, we confirmed the efficacy of this strategy in multiple cancer models and revealed the mechanism of cell death. Our strategy might provide a novel concept for precise cancer therapy.

Intravenous Alteplase in a Patient With Acute Ischemic Stroke Subsequent to Purulent Meningitis: A Case Report and Literature Review.

This report highlights the outcome of intravenous alteplase in a patient with acute ischemic stroke subsequent to purulent meningitis. This type of meningitis has not been defined in the guideline for early treatment of acute ischemic stroke. A 58-year-old woman with purulent meningitis developed a sudden stroke and was admitted to our emergency department. She received 0.6 mg/kg of alteplase intravenously 90 minutes after stroke onset. At 1 hour after thrombolysis, the patient's National Institute of Health Stroke Scale score improved from 9 to 4. At 2 hours, she developed a sudden severe headache that progressed to coma, and her National Institute Health Stroke Scale score rapidly deteriorated to 20. Cranial computed tomography revealed subarachnoid hemorrhage and multiple bilateral lobar brain hemorrhages. She died of a cerebellar tonsillar hernia. Intravenous alteplase might be hazardous in patients with acute ischemic stroke subsequent to purulent meningitis.

Efficacy of the ketogenic diet in Chinese adults versus children with drug-resistant epilepsy: A pilot study.

OBJECTIVE: We compared the efficacy and safety of ketogenic diet (KD) therapy as a treatment for Chinese adults versus children with drug-resistant epilepsy. METHODS: The classic KD was initiated in 19 adults and 29 children with drug-resistant epilepsy. The KD ratio and the dosage of antiseizure medication (ASM) were delicately modulated by the ketogenic team. RESULTS: At 12 months after diet initiation, 11 adults (8 on a KD ratio of 3:1 and 3 on a ratio of 2:1) and 20 children (9 on a ketogenic diet ratio of 3:1 and 11 on a ratio of 2:1) remained on the diet. The retention rate for adult KD therapy recipients was 79.0% at 6 months and 57.9% at 12 months after diet initiation, which was not significantly different from the retention rate for children (82.8% at 6 months and 68.9% at 12 months; P > 0.05). The efficacy rate of KD therapy (seizure freedom or ≥50% reduction in seizure frequency) did not significantly differ between adults (63.2%) and children (75.8%, P = 0.517). Alleviation of seizure severity was observed in 68.4% of adults and 63.6% of children who were not seizure free on KD therapy. Antiseizure medication was reduced in 34 out of all 48 individuals at the final follow-up. CONCLUSION: Our study demonstrated that KD therapy is a safe and effective treatment for Chinese adults as well as children with drug-resistant epilepsy.

Magnetic Resonance Imaging throughout the Clinical Course of Schizophrenia: Neurobiological Underpinnings and Clinical Implications.

As a non-invasive detection method and an advanced imaging method, magnetic resonance imaging (MRI) has been widely used in the research of schizophrenia. Although a large number of neuroimaging studies have confirmed that MRI can display abnormal brain phenotypes in patients with schizophrenia, no valid uniform standard has been established for its clinical application. On the basis of previous evidence, we argue that MRI is an important tool throughout the whole clinical course of schizophrenia. The purpose of this commentary is to systematically describe the role of MRI in schizophrenia and to provide references for its clinical application.

Engineering of Bacillus Promoters Based on Interacting Motifs between UP Elements and RNA Polymerase (RNAP) α-Subunit.

Bacillus genetics need more versatile promoters for gene circuit engineering. UP elements are widely distributed in noncoding regions and interact with the α-subunit of RNA polymerase (RNAP). They can be applied as a standard element for synthetic biology. Characterization of the binding motif between UP elements and RNAP may assist with rational and effective engineering. In this study, 11 Bacillus constitutive promoters were screened for strength in Bacillus licheniformis. The motif in UP elements from a strong native promoter, PLan, was characterized. The influence of specific sequences on RNAP binding and expression strength was investigated both in vitro and in vivo. It was found that sequences up to 50 base pairs upstream of the consensus motif significantly contributed to α-CTD (the alpha subunit carboxy-terminal domain) association. Meanwhile, two repeats of a proximal subsite were able to more strongly activate the expression (by 8.2-fold) through strengthening interactions between UP elements and RNAP. Based the above molecular basis, a synthetic UP element, UP5-2P, was constructed and applied to nine wild-type promoters. Fluorescence polarization results demonstrated that it had an apparent effect on promoter-α-CTD interactions, and elevated expression strength was observed for all the engineered promoters. The highest improved core promoter, Pacpp, was more strongly activated by 7.4-fold. This work thus develops a novel strategy for Bacillus promoter engineering.

Astragalus polysaccharide attenuates LPS-related inflammatory osteolysis by suppressing osteoclastogenesis by reducing the MAPK signalling pathway.

Bacterial products can stimulate inflammatory reaction and activate immune cells to enhance the production of inflammatory cytokines, and finally promote osteoclasts recruitment and activity, leading to bone destruction. Unfortunately, effective preventive and treatment measures for inflammatory osteolysis are limited and usually confuse the orthopedist. Astragalus polysaccharide (APS), the main extractive of Astragali Radix, has been widely used for treating inflammatory diseases. In the current study, in vitro and in vivo experimental results demonstrated that APS notably inhibited osteoclast formation and differentiation dose-dependently. Moreover, we found that APS down-regulated RANKL-related osteoclastogenesis and levels of osteoclast marker genes, such as NFATC1, TRAP, c-FOS and cathepsin K. Further underlying mechanism investigation revealed that APS attenuated activity of MAPK signalling pathways (eg ERK, JNK and p38) and ROS production induced by RANKL. Additionally, APS was also found to suppress LPS-related inflammatory osteolysis by decreasing inflammatory factors' production in vivo. Overall, our findings demonstrate that APS effectively down-regulates inflammatory osteolysis due to osteoclast differentiation and has the potential to become an effective treatment of the disorders associated with osteoclast.

Baseline structural and functional magnetic resonance imaging predicts early treatment response in schizophrenia with radiomics strategy.

Multimodal neuroimaging features provide opportunities for accurate classification and personalized treatment options in the psychiatric domain. This study aimed to investigate whether brain features predict responses to the overall treatment of schizophrenia at the end of the first or a single hospitalization. Structural and functional magnetic resonance imaging (MRI) data from two independent samples (N = 85 and 63, separately) of schizophrenia patients at baseline were included. After treatment, patients were classified as responders and non-responders. Radiomics features of gray matter morphology and functional connectivity were extracted using Least Absolute Shrinkage and Selection Operator. Support vector machine was used to explore the predictive performance. Prediction models were based on structural features (cortical thickness, surface area, gray matter regional volume, mean curvature, metric distortion, and sulcal depth), functional features (functional connectivity), and combined features. There were 12 features after dimensionality reduction. The structural features involved the right precuneus, cuneus, and inferior parietal lobule. The functional features predominately included inter-hemispheric connectivity. We observed a prediction accuracy of 80.38% (sensitivity: 87.28%; specificity 82.47%) for the model using functional features, and 69.68% (sensitivity: 83.96%; specificity: 72.41%) for the one using structural features. Our model combining both structural and functional features achieved a higher accuracy of 85.03%, with 92.04% responder and 80.23% non-responders to the overall treatment to be correctly predicted. These results highlight the power of structural and functional MRI-derived radiomics features to predict early response to treatment in schizophrenia. Prediction models of the very early treatment response in schizophrenia could augment effective therapeutic strategies.

Safety, tolerability, and immunogenicity of a recombinant adenovirus type-5 vectored COVID-19 vaccine: a dose-escalation, open-label, non-randomised, first-in-human trial.

BACKGROUND: A vaccine to protect against COVID-19 is urgently needed. We aimed to assess the safety, tolerability, and immunogenicity of a recombinant adenovirus type-5 (Ad5) vectored COVID-19 vaccine expressing the spike glycoprotein of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain. METHODS: We did a dose-escalation, single-centre, open-label, non-randomised, phase 1 trial of an Ad5 vectored COVID-19 vaccine in Wuhan, China. Healthy adults aged between 18 and 60 years were sequentially enrolled and allocated to one of three dose groups (5 × 1010, 1 × 1011, and 1·5 × 1011 viral particles) to receive an intramuscular injection of vaccine. The primary outcome was adverse events in the 7 days post-vaccination. Safety was assessed over 28 days post-vaccination. Specific antibodies were measured with ELISA, and the neutralising antibody responses induced by vaccination were detected with SARS-CoV-2 virus neutralisation and pseudovirus neutralisation tests. T-cell responses were assessed by enzyme-linked immunospot and flow-cytometry assays. This study is registered with ClinicalTrials.gov, NCT04313127. FINDINGS: Between March 16 and March 27, 2020, we screened 195 individuals for eligibility. Of them, 108 participants (51% male, 49% female; mean age 36·3 years) were recruited and received the low dose (n=36), middle dose (n=36), or high dose (n=36) of the vaccine. All enrolled participants were included in the analysis. At least one adverse reaction within the first 7 days after the vaccination was reported in 30 (83%) participants in the low dose group, 30 (83%) participants in the middle dose group, and 27 (75%) participants in the high dose group. The most common injection site adverse reaction was pain, which was reported in 58 (54%) vaccine recipients, and the most commonly reported systematic adverse reactions were fever (50 [46%]), fatigue (47 [44%]), headache (42 [39%]), and muscle pain (18 [17%]. Most adverse reactions that were reported in all dose groups were mild or moderate in severity. No serious adverse event was noted within 28 days post-vaccination. ELISA antibodies and neutralising antibodies increased significantly at day 14, and peaked 28 days post-vaccination. Specific T-cell response peaked at day 14 post-vaccination. INTERPRETATION: The Ad5 vectored COVID-19 vaccine is tolerable and immunogenic at 28 days post-vaccination. Humoral responses against SARS-CoV-2 peaked at day 28 post-vaccination in healthy adults, and rapid specific T-cell responses were noted from day 14 post-vaccination. Our findings suggest that the Ad5 vectored COVID-19 vaccine warrants further investigation. FUNDING: National Key R&D Program of China, National Science and Technology Major Project, and CanSino Biologics.

Optimum chalcone synthase for flavonoid biosynthesis in microorganisms.

Chalcones and the subsequently generated flavonoids, as well as flavonoid derivatives, have been proven to have a variety of physiological activities and are widely used in: the pharmaceutical, food, feed, and cosmetic industries. As the content of chalcones and downstream products in native plants is low, the production of these compounds by microorganisms has gained the attention of many researchers and has a history of more than 20 years. The mining and engineering of chalcone synthase (CHS) could be one of the most important ways to achieve more efficient production of chalcones and downstream products in microorganisms. CHS has a broad spectrum of substrates, and its enzyme activity and expression level can significantly affect the efficiency of the biosynthesis of flavonoids. This review summarizes the recent advances in the: structure, mechanism, evolution, substrate spectrum, transformation, and expression regulation in the flavonoid biosynthesis of this vital enzyme. Future development directions were also suggested. The findings may further promote the research and development of flavonoids and health products, making them vital in the fields of human diet and health.