Unveiling the regulatory mechanisms of nodules development and quality formation in Panax notoginseng using multi-omics and MALDI-MSI.

INTRODUCTION: Renowned for its role in traditional Chinese medicine, Panax notoginseng exhibits healing properties including bidirectional regulatory effects on hematological system diseases. However, the presence of nodular structures near the top of the main root, known as nail heads, may impact the quality of the plant's valuable roots. OBJECTIVES: In this paper, we aim to systematically analyze nail heads to identify their potential correlation with P. notoginseng quality. Additionally, we will investigate the molecular mechanisms behind nail head development. METHODS: Morphological characteristics and anatomical features were analyzed to determine the biological properties of nail heads. Active component analysis and MALDI mass spectrometry imaging (MALDI-MSI) were performed to determine the correlation between nail heads and P. notoginseng quality. Phytohormone quantitation, MALDI-MSI, RNA-seq, and Arabidopsis transformation were conducted to elucidate the mechanisms of nail head formation. Finally, protein-nucleic acid and protein-protein interactions were investigated to construct a transcriptional regulatory network of nodule development and quality formation. RESULTS: Our analyses have revealed that nail heads originate from an undeveloped lateral root. The content of ginsenosides was found to be positively associated with the amount of nail heads. Ginsenoside Rb1 specifically accumulated in the cortex of nail heads, while IAA, tZR and JAs also showed highest accumulation in the nodule. RNA-seq analysis identified PnIAA14 and PnCYP735A1 as inhibitors of lateral root development. PnMYB31 and PnMYB78 were found to form binary complexes with PnbHLH31 to synergistically regulate the expression of PnIAA14, PnCYP735A1, PnSS, and PnFPS. CONCLUSION: Our study details the major biological properties of nodular structures in P. notoginseng and outlines their impact on the quality of the herb. It was also determined that PnMYB31- and PnMYB78-PnbHLH31 regulate phytohormones and ginsenosides accumulation, further affecting plant development and quality. This research provides insights for quality evaluation and clinical applications of P. notoginseng.

Synergistic Development of Natural Rubber/Butyl Rubber Composites for Improved Interfacial Bonding and Enhanced Shock-Absorbing Capabilities.

Shock-absorbing materials play a vital role in various industrial sectors, including construction and transportation. Among these materials, natural rubber (NR) stands out due to its exceptional elastic and mechanical properties, coupled with its robust crack resistance. Nevertheless, with the rising demand for enhanced damping capacities, there is a need to further optimize the damping performance of NR. One direct approach is to blend it with high-damping rubber. Butyl rubber (IIR) is a prominent member of the high-damping rubber category. Integrating IIR effectively with the NR, however, presents challenges. These challenges arise from IIR's inherent characteristics, such as its low unsaturation, slower vulcanization rate, and restricted compatibility with NR. Addressing these challenges, our study employed isoprene and isobutene to synthesize a variant of butyl rubber with a higher degree of unsaturation-achieving an unsaturation level between 4 and 6 mol %. Notably, this heightened unsaturation significantly expedited the curing time of IIR and facilitated the concurrent vulcanization of both IIR and NR. Utilizing atomic force microscopy, we observed that the introduction of unsaturated double bonds ameliorated the compatibility between NR and IIR, leading to an interfacial region extending up to 1000 nm. Our tests using a dynamic mechanical analyzer and rubber processing analyzer demonstrated the material's damping temperature range. Furthermore, there was a noticeable rise in the loss factor (tan δ) at ambient temperature, which remains over 0.1 across both a frequency window of 0.2 to 5 Hz and a strain spectrum of 10 to 200%. This tan δ enhancement ensured the potential of these rubber composites for shock-absorbing applications.

GCN5 mediates DNA-PKcs crotonylation for DNA double-strand break repair and determining cancer radiosensitivity.

BACKGROUND: DNA double-strand break (DSB) induction and repair are important events for determining cell survival and the outcome of cancer radiotherapy. The DNA-dependent protein kinase (DNA-PK) complex functions at the apex of DSBs repair, and its assembly and activity are strictly regulated by post-translation modifications (PTMs)-associated interactions. However, the PTMs of the catalytic subunit DNA-PKcs and how they affect DNA-PKcs's functions are not fully understood. METHODS: Mass spectrometry analyses were performed to identify the crotonylation sites of DNA-PKcs in response to γ-ray irradiation. Co-immunoprecipitation (Co-IP), western blotting, in vitro crotonylation assays, laser microirradiation assays, in vitro DNA binding assays, in vitro DNA-PK assembly assays and IF assays were employed to confirm the crotonylation, identify the crotonylase and decrotonylase, and elucidate how crotonylation regulates the activity and function of DNA-PKcs. Subcutaneous xenografts of human HeLa GCN5 WT or HeLa GCN5 siRNA cells in BALB/c nude mice were generated and utilized to assess tumor proliferation in vivo after radiotherapy. RESULTS: Here, we reveal that K525 is an important site of DNA-PKcs for crotonylation, and whose level is sharply increased by irradiation. The histone acetyltransferase GCN5 functions as the crotonylase for K525-Kcr, while HDAC3 serves as its dedicated decrotonylase. K525 crotonylation enhances DNA binding activity of DNA-PKcs, and facilitates assembly of the DNA-PK complex. Furthermore, GCN5-mediated K525 crotonylation is indispensable for DNA-PKcs autophosphorylation and the repair of double-strand breaks in the NHEJ pathway. GCN5 suppression significantly sensitizes xenograft tumors of mice to radiotherapy. CONCLUSIONS: Our study defines K525 crotonylation of DNA-PKcs is important for the DNA-PK complex assembly and DSBs repair activity via NHEJ pathway. Targeting GCN5-mediated K525 Kcr of DNA-PKcs may be a promising therapeutic strategy for improving the outcome of cancer radiotherapy.

Combination of secukinumab and acitretin for generalized pustular psoriasis: A case report and review of literature.

Generalized pustular psoriasis (GPP) is characterized by painful and occasionally disfiguring cutaneous manifestations with sepsis-like systemic symptoms, and is a rare severe variant of psoriasis. Currently, there is no standard treatment for GPP. Here, we report a case of a female patient with ankylosing spondylitis (AS) and mild scalp psoriasis, who developed GPP and alopecia following three courses of adalimumab therapy. The patient's condition gradually improved following cessation of adalimumab and treatment with secukinumab and acitretin. After eight weeks of treatment, the patient achieved almost complete clearance of her psoriasis, her alopecia improved, and her AS was relieved. Therefore, we believe that a combination of secukinumab with acitretin may be a rational approach for the treatment of severe GPP.

In vivo EPID-based daily treatment error identification for volumetric-modulated arc therapy in head and neck cancers with a hierarchical convolutional neural network: a feasibility study.

We proposed a deep learning approach to classify various error types in daily VMAT treatment of head and neck cancer patients based on EPID dosimetry, which could provide additional information to support clinical decisions for adaptive planning. 146 arcs from 42 head and neck patients were analyzed. Anatomical changes and setup errors were simulated in 17,820 EPID images of 99 arcs obtained from 30 patients using in-house software for model training, validation, and testing. Subsequently, 141 clinical EPID images from 47 arcs belonging to the remaining 12 patients were utilized for clinical testing. The hierarchical convolutional neural network (HCNN) model was trained to classify error types and magnitudes using EPID dose difference maps. Gamma analysis with 3%/2 mm (dose difference/distance to agreement) criteria was also performed. The F1 score, a combination of precision and recall, was utilized to evaluate the performance of the HCNN model and gamma analysis. The adaptive fractioned doses were calculated to verify the HCNN classification results. For error type identification, the overall F1 score of the HCNN model was 0.99 and 0.91 for primary type and subtype identification, respectively. For error magnitude identification, the overall F1 score in the simulation dataset was 0.96 and 0.70 for the HCNN model and gamma analysis, respectively; while the overall F1 score in the clinical dataset was 0.79 and 0.20 for the HCNN model and gamma analysis, respectively. The HCNN model-based EPID dosimetry can identify changes in patient transmission doses and distinguish the treatment error category, which could potentially provide information for head and neck cancer treatment adaption.

Increased prevalence of CFTR variants and susceptibility to CRS: A real-world study based on Chinese children.

Background: Chronic Rhinosinusitis is a common disease in children. The main function of CFTR is to maintain the thickness of the mucous layer on the surface of the nasal mucosa. CFTR disease-causing variant can cause CFTR protein dysfunction and induce or aggravate chronic infection. However, the carrying status of the CFTR variants in the Chinese population is not clear. Objective: To study the frequency and variants of CFTR in Chinese children with CRS and to analyze the CFTR variants and the clinical characteristics and susceptibility to CRS. Methods: Whole Exome Sequencing was performed to analyze the CFTR genes in a total of 106 CRS children from the Chinese mainland area. The CFTR variants, frequency and clinical data were summarized and analyzed. Results: A total of 31 CFTR variants were detected, of which the carrying rate of 7 sites was significantly higher than that of the population database. 88 patients carried more than 2 variants. 37 people carried variants (MAF < 0.05), of which 91.89% had a history of recurrent upper respiratory infections, 16 had nasal polyps, 5 had bronchiectasis, and 1 was diagnosed with CF-related disorders. Conclusion: The carrying rate of CFTR variants in Chinese CRS children increased, and the highest rates of variants (MAF < 0.05) are p.I556V, p. E217G, c.1210-12[T]. Carrying multiple CFTR variants, especially p.E217G, p.I807 M, p.V920L and c.1210-12[T] may lead to increased susceptibility to CRS. There are CF-related disorders in patients with CRS.

Longitudinal multi-omics analysis uncovers the altered landscape of gut microbiota and plasma metabolome in response to high altitude.

BACKGROUND: Gut microbiota is significantly influenced by altitude. However, the dynamics of gut microbiota in relation to altitude remains undisclosed. METHODS: In this study, we investigated the microbiome profile of 610 healthy young men from three different places in China, grouped by altitude, duration of residence, and ethnicity. We conducted widely targeted metabolomic profiling and clinical testing to explore metabolic characteristics. RESULTS: Our findings revealed that as the Han individuals migrated from low altitude to high latitude, the gut microbiota gradually converged towards that of the Tibetan populations but reversed upon returning to lower altitude. Across different cohorts, we identified 51 species specifically enriched during acclimatization and 57 species enriched during deacclimatization to high altitude. Notably, Prevotella copri was found to be the most enriched taxon in both Tibetan and Han populations after ascending to high altitude. Furthermore, significant variations in host plasma metabolome and clinical indices at high altitude could be largely explained by changes in gut microbiota composition. Similar to Tibetans, 41 plasma metabolites, such as lactic acid, sphingosine-1-phosphate, taurine, and inositol, were significantly elevated in Han populations after ascending to high altitude. Germ-free animal experiments demonstrated that certain species, such as Escherichia coli and Klebsiella pneumoniae, which exhibited altitude-dependent variations in human populations, might play crucial roles in host purine metabolism. CONCLUSIONS: This study provides insights into the dynamics of gut microbiota and host plasma metabolome with respect to altitude changes, indicating that their dynamics may have implications for host health at high altitude and contribute to host adaptation. Video Abstract.

FGF7 enhances the expression of ACE2 in human islet organoids aggravating SARS-CoV-2 infection.

The angiotensin-converting enzyme 2 (ACE2) is a primary cell surface viral binding receptor for SARS-CoV-2, so finding new regulatory molecules to modulate ACE2 expression levels is a promising strategy against COVID-19. In the current study, we utilized islet organoids derived from human embryonic stem cells (hESCs), animal models and COVID-19 patients to discover that fibroblast growth factor 7 (FGF7) enhances ACE2 expression within the islets, facilitating SARS-CoV-2 infection and resulting in impaired insulin secretion. Using hESC-derived islet organoids, we demonstrated that FGF7 interacts with FGF receptor 2 (FGFR2) and FGFR1 to upregulate ACE2 expression predominantly in ß cells. This upregulation increases both insulin secretion and susceptibility of ß cells to SARS-CoV-2 infection. Inhibiting FGFR counteracts the FGF7-induced ACE2 upregulation, subsequently reducing viral infection and replication in the islets. Furthermore, retrospective clinical data revealed that diabetic patients with severe COVID-19 symptoms exhibited elevated serum FGF7 levels compared to those with mild symptoms. Finally, animal experiments indicated that SARS-CoV-2 infection increased pancreatic FGF7 levels, resulting in a reduction of insulin concentrations in situ. Taken together, our research offers a potential regulatory strategy for ACE2 by controlling FGF7, thereby protecting islets from SARS-CoV-2 infection and preventing the progression of diabetes in the context of COVID-19.

Rationally designing of Co-WS2 catalysts with optimized electronic structure to enhance hydrogen evolution reaction.

Designing and developing cost-effective, high-performance catalysts for hydrogen evolution reaction (HER) is crucial for advancing hydrogen production technology. Tungsten-based sulfides (WSx) exhibit great potential as efficient HER catalysts, however, the activity is limited by the larger energy required for water dissociation under alkaline conditions. Herein, we adopt a top-down strategy to construct heterostructure Co-WS2 nanofiber catalysts. The experimental results and theoretical simulations unveil that the work functions-induced built-in electric field at the interface of Co-WS2 catalysts facilitates the electron transfer from Co to WS2, significantly reducing water dissociation energy and optimizing the Gibbs free energy of the entire reaction step for HER. Besides, the self-supported catalysts of Co-WS2 nanoparticles confining 1D nanofibers exhibit an increased number of active sites. As expected, the heterostructure Co-WS2 catalysts exhibit remarkable HER activity with an overpotential of 113 mV to reach 10 mA cm-2 and stability with 30 h catalyzing at 23 mA cm-2. This work can provide an avenue for designing highly efficient catalysts applicable to the field of energy storage and conversion.

An Iteratively Extended Target Tracking by Using Decorrelated Unbiased Conversion of Nonlinear Measurements.

Extended target tracking (ETT) based on random matrices typically assumes that the measurement model is linear. However, nonlinear measurements (such as range and azimuth) depending on locations of a series of unknown scattering centers always exist in many practical tracking applications. To address this issue, this paper proposes an iteratively extended target tracking based on random matrices by using decorrelated unbiased conversion of nonlinear measurements (ETT-IDUCM). First, we utilize a decorrelated unbiased converted measurement (DUCM) method to convert nonlinear measurements depending on unknown scatters of target extent in polar coordinates into the ones in Cartesian coordinates with equivalent measurement noise covariances. Subsequently, a novel method, combining iteratively extended Kalman filter (IEKF) updates with variational Bayesian (VB) cycles is developed for precise estimation of the target's kinematic state and extension. This method leverages the synergy between external IEKF iterations, which use the estimated state as a new prediction and input for DUCM, and internal VB iterations, which realize a closed-form approximation of the joint posterior probability. This approach progressively enhances estimation accuracy. Simulation results demonstrate the ETT-IDUCM algorithm's superior precision in estimating the target's kinematic state and extension compared to existing methods.

Extended Conjugation Strategy Enabling Red-Shifted and Efficient Emission of Orange-Red Thermally Activated Delayed Fluorescence Materials.

In account of the energy gap law, the development of efficient narrow-band gap thermally activated delayed fluorescence (TADF) materials remains a major challenge for the application of organic light-emitting diodes (OLEDs). The orange-red TADF materials are commonly designed with either large π-conjugated systems or strong intramolecular donor-acceptor (D-A) interactions for red-shift emission and small singlet-triplet energy gap (ΔEST). There are rare reports on the simultaneous incorporation of these two strategies on the same material systems. Herein, two orange-red emitters named 1P2D-BP and 2P2D-DQ have been designed by extending the conjugation degree of the center acceptor DQ and increasing the number distribution of the peripheral donor PXZ units, respectively. The emission peak of 1P2D-BP is red-shifted to 615 nm compared to 580 nm for 2P2D-DQ, revealing the pronounced effect of the conjugation extension on the emission band gap. In addition, the distorted molecular structure yields a small ΔEST of 0.02 eV, favoring the acquisition of a high exciton utilization through an efficient reverse intersystem crossing process. As a result, orange-red OLEDs with both 1P2D-BP and 2P2D-DQ have achieved an external quantum efficiency (EQE) of more than 17%. In addition, the efficient white OLED based on 1P2D-BP is realized through precise exciton assignment and energy transport modulation, showing an EQE of 23.6% and a color rendering index of 82. The present work provides an important reference for the design of high-efficiency narrow-band gap materials in the field of solid-state lighting.

Efficacy of flexible ureterorenoscopy with holmium laser in the management of calyceal diverticular calculi.

The purpose of this study was to evaluate the efficacy and safety of flexible ureteroscopy with holmium laser lithotripsy in the management of calyceal diverticular calculi. In this study, we retrospectively analyzed the clinical data of 27 patients with calyceal diverticular calculi admitted to the Department of Urology of the Zigong First People's Hospital from May 2018 to May 2021. Intraoperatively, the diverticular neck was found in all 27 patients, but flexible ureterorenoscopy lithotripsy was not performed in 2 cases because of the slender diverticular neck, and the success rate of the operation was 92.6%. Of the 25 patients with successful lithotripsy, the mean operative time was 76.9 ± 35.5 (43-200) min. There were no serious intraoperative complications such as ureteral perforation, mucosal avulsion, or hemorrhage. Postoperative minor complications (Clavien classification I-II) occurred in 4 (16%) patients. The mean hospital stay was 4.4 ± 1.7 (3-12) days. The stone-free rate was 80% at the 1-month postoperative follow-up. After the second-stage treatment, the stone-free rate was 88%. In 22 cases with complete stone clearance, no stone recurrence was observed at 5.3 ± 2.6 (3-12) months follow-up. This retrospective study demonstrated that flexible ureterorenoscopy with holmium laser is a safe and effective choice for the treatment of calyceal diverticular calculi, because it utilizes the natural lumen of the human body and has the advantages of less trauma, fewer complications, and a higher stone-free rate.

Crystal structure of the ATPase domain of porcine circovirus type 2 Rep protein.

PCV2 belongs to the genus Circovirus in the family Circoviridae, whose genome is replicated by rolling circle replication (RCR). PCV2 Rep is a multifunctional enzyme that performs essential functions at multiple stages of viral replication. Rep is responsible for nicking and ligating single-stranded DNA and unwinding double-stranded DNA (dsDNA). However, the structure and function of the Rep are still poorly understood, which significantly impedes viral replication research. This study successfully resolved the structure of the PCV2 Rep ATPase domain (PRAD) using X-ray crystallography. Homologous structure search revealed that Rep belonged to the superfamily 3 (SF3) helicase, and multiple conserved residues were identified during sequence alignment with SF3 family members. Simultaneously, a hexameric PRAD model was generated for analysing characteristic structures and sites. Mutation of the conserved site and measurement of its activity showed that the hallmark motifs of the SF3 family influenced helicase activity by affecting ATPase activity and ß-hairpin just caused the loss of helicase activity. The structural and functional analyses of the PRAD provide valuable insights for future research on PCV2 replication and antiviral strategies.

Universal Design and Efficient Synthesis for High Ambipolar Mobility Emissive Conjugated Polymers.

High ambipolar mobility emissive conjugated polymers (HAME-CPs) are perfect candidates for organic optoelectronic devices, such as polymer light emitting transistors. However, due to intrinsic trade-off relationship between high ambipolar mobility and strong solid-state luminescence, the development of HAME-CPs suffers from high structural and synthetic complexity. Herein, a universal design principle and simple synthetic approach for HAME-CPs are developed. A series of simple non-fused polymers composed of charge transfer units, π bridges and emissive units are synthesized via a two-step microwave assisted C-H arylation and direct arylation polymerization protocol with high total yields up to 61 %. The synthetic protocol is verified valid among 7 monomers and 8 polymers. Most importantly, all 8 conjugated polymers have strong solid-state emission with high photoluminescence quantum yields up to 24 %. Furthermore, 4 polymers exhibit high ambipolar field effect mobility up to 10-2 cm2 V-1 s-1, and can be used in multifunctional optoelectronic devices. This work opens a new avenue for developing HAME-CPs by efficient synthesis and rational design.

Effect of Corticosteroids on Long-term Humoral and Memory T-Cell Responses in Follow-up Visit of Hospitalized Patients With COVID-19.

BACKGROUND: Corticosteroids have beneficial effects in improving outcomes in hospitalized patients with severe COVID-19 by suppressing excessive immune responses. However, the effect of corticosteroids on the humoral and T-cell responses of survivors of COVID-19 1 year after infection remains uncertain because it relates to the extent of immediate, antigen-specific defense provided by protective memory. RESEARCH QUESTION: What is the effect of corticosteroids on long-term humoral and T-cell immune responses? STUDY DESIGN AND METHODS: In this retrospective cohort study conducted at a single center, we analyzed data from a cohort who had survived COVID-19 to compare the 1-year seropositivity and titer changes in neutralizing antibodies (NAbs) and SARS-CoV-2-specific antibodies. Additionally, we evaluated the magnitude and rate of SARS-CoV-2-specific T-cell response in individuals who received corticosteroids during hospitalization and those who did not. RESULTS: Our findings indicated that corticosteroids do not statistically influence the kinetics or seropositive rate of NAbs against the Wuhan strain of SARS-CoV-2 from 6 months to 1 year. However, subgroup analysis revealed a numerical increase of absolute NAbs titers, from 20.0 to 28.2, in categories where long-term (> 15 days) and high-dose (> 560 mg) corticosteroids are administered. Similarly, corticosteroids showed no significant effect on nucleoprotein and receptor-binding domain IgG at 1 year, except for spike protein IgG (ß, 0.08; 95% CI, 0.04-0.12), which demonstrated a delayed decline of titers. Regarding T-cell immunity, corticosteroids did not affect the rate or magnitude of T-cell responses significantly. However, functional assessment of memory T cells revealed higher interferon-γ responses in CD4 (ß, 0.61; 95% CI, 0.10-1.12) and CD8 (ß, 0.63; 95% CI, 0.11-1.15) memory T cells in the corticosteroids group at 1 year. INTERPRETATION: Based on our findings, short-term and low-dose corticosteroid therapy during hospitalization does not have a significant effect on long-term humoral kinetics or the magnitude and rate of memory T-cell responses to SARS-CoV-2 antigens. However, the potential harmful effects of long-term and high-dose corticosteroid use on memory immune responses require further investigation.

TAB182 regulates glycolytic metabolism by controlling LDHA transcription to impact tumor radiosensitivity.

Metabolic reprogramming, a hallmark of cancer, is closely associated with tumor development and progression. Changes in glycolysis play a crucial role in conferring radiation resistance to tumor cells. How radiation changes the glycolysis status of cancer cells is still unclear. Here we revealed the role of TAB182 in regulating glycolysis and lactate production in cellular response to ionizing radiation. Irradiation can significantly stimulate the production of TAB182 protein, and inhibiting TAB182 increases cellular radiosensitivity. Proteomic analysis indicated that TAB182 influences several vital biological processes, including multiple metabolic pathways. Knockdown of TAB182 results in decreased lactate production and increased pyruvate and ATP levels in cancer cells. Moreover, knocking down TAB182 reverses radiation-induced metabolic changes, such as radioresistant-related lactate production. TAB182 is necessary for activating LDHA transcription by affecting transcription factors SP1 and c-MYC; its knockdown attenuates the upregulation of LDHA by radiation, subsequently suppressing lactate production. Targeted suppression of TAB182 significantly enhances the sensitivity of murine xenograft tumors to radiotherapy. These findings advance our understanding of glycolytic metabolism regulation in response to ionizing radiation, which may offer significant implications for developing new strategies to overcome tumor radioresistance.

Differentiating Cell Entry Potentials of SARS-CoV-2 Omicron Subvariants on Human Lung Epithelium Cells.

The surface spike (S) glycoprotein mediates cell entry of SARS-CoV-2 into the host through fusion at the plasma membrane or endocytosis. Omicron lineages/sublineages have acquired extensive mutations in S to gain transmissibility advantages and altered antigenicity. The fusogenicity, antigenicity, and evasion of Omicron subvariants have been extensively investigated at unprecedented speed to align with the mutation rate of S. Cells that overexpress receptors/cofactors are mostly used as hosts to amplify infection sensitivity to tested variants. However, systematic cell entry comparisons of most prior dominant Omicron subvariants using human lung epithelium cells are yet to be well-studied. Here, with human bronchial epithelium BEAS-2B cells as the host, we compared single-round virus-to-cell entry and cell-to-cell fusion of Omicron BA.1, BA.5, BQ.1.1, CH.1.1, XBB.1.5, and XBB.1.16 based upon split NanoLuc fusion readout assays and the S-pseudotyped lentivirus system. Virus-to-cell entry of tested S variants exhibited cell-type dependence. The parental Omicron BA.1 required more time to develop full entry to HEK293T-ACE2-TMPRSS2 than BEAS-2B cells. Compared to unchanged P681, S-cleavage constructs of P681H/R did not have any noticeable advantages in cell entry. Omicron BA.1 and its descendants entered BEAS-2B cells more efficiently than D614G, and it was slightly less or comparable to that of Delta. Serine protease-pretreated Omicron subvariants enhanced virus-to-cell entry in a dose-dependent manner, suggesting fusion at the plasma membrane persists as a productive cell entry route. Spike-mediated cell-to-cell fusion and total S1/S2 processing of Omicron descendants were similar. Our results indicate no obvious entry or fusion advantages of recent Omicron descendants over preceding variants since Delta, thus supporting immune evasion conferred by antigenicity shifts due to altered S sequences as probably the primary viral fitness driver.

Latent class analysis of chest CT abnormalities to define subphenotypes in patients with MPO-ANCA-positive microscopic polyangiitis.

BACKGROUND: Patients with microscopic polyangiitis (MPA) and positive myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) may present with various abnormalities in chest computed tomography (CT). This study aimed to identify subphenotypes using latent class analysis (LCA) and to explore the relationship between the subphenotypes and clinical patterns, as well as compare the clinical characteristics of these subphenotypes in patients with MPO-ANCA-positive MPA (MPO-MPA). METHODS: The study identified subphenotypes using LCA based on chest CT findings in 178 patients with MPO-MPA and pulmonary involvement from June 2014 to August 2022. RESULTS: LCA identified 27 participants (15.2%) in class 1, 43 (24.1%) in class 2, 35 (19.7%) in class 3, and 73 (41.0%) in class 4. Class 1 was characterized by prominent inflammatory exudation, class 2 by fibrosis and architectural distortion, class 3 by predominantly bronchiectasis, and class 4 by lesions mixed with inflammation and fibrosis. Class 1 had the highest level of extrapulmonary disease activity, with 77.8% of patients experiencing diffuse alveolar hemorrhage. Class 2 had the lowest level of extrapulmonary disease activity, with 41.9% of patients showing usual interstitial pneumonia. Class 3 patients were more likely to have complications involving the ear, nose, and throat, as well as pulmonary infections before treatment, and they exhibited the best outcomes. The characteristics and outcomes of class 4 were intermediate among the four classes. CONCLUSIONS: These findings suggest that bronchiectasis may represent a unique pattern of pulmonary involvement in MPO-MPA, highlighting the importance of screening for bronchiectasis in MPO-MPA and identifying optimal management strategies.

Fast and sensitive CRISPR detection by minimized interference of target amplification.

Despite the great potential of CRISPR-based detection, it has not been competitive with other market diagnostics for on-site and in-home testing. Here we dissect the rate-limiting factors that undermine the performance of Cas12b- and Cas13a-mediated detection. In one-pot testing, Cas12b interferes with loop-mediated isothermal amplification by binding to and cleaving the amplicon, while Cas13a directly degrades the viral RNA, reducing its amplification. We found that the protospacer-adjacent motif-interacting domain engineered Cas12b accelerated one-pot testing with 10-10,000-fold improved sensitivity, and detected 85 out of 85 SARS-CoV-2 clinical samples with a sensitivity of 0.5 cp µl-1, making it superior to wild-type Cas12b. In parallel, by diminishing the interference of Cas13a with viral RNA, the optimized Cas13a-based assay detected 86 out of 87 SARS-CoV-2 clinical samples at room temperature in 30 min with a sensitivity of 0.5 cp µl-1. The relaxed reaction conditions and improved performance of CRISPR-based assays make them competitive for widespread use in pathogen detection.

Highly Promiscuous Flavonoid Di-O-glycosyltransferases from Carthamus tinctorius L.

Safflower (Carthamus tinctorius L.) has been recognized for its medicinal value, but there have been limited studies on the glycosyltransferases involved in the biosynthesis of flavonoid glycosides from safflower. In this research, we identified two highly efficient flavonoid O-glycosyltransferases, CtOGT1 and CtOGT2, from safflower performing local BLAST alignment. By constructing a prokaryotic expression vector, we conducted in vitro enzymatic reactions and discovered that these enzymes were capable of catalyzing two-step O-glycosylation using substrates such as kaempferol, quercetin, and eriodictyol. Moreover, they exhibited efficient catalytic activity towards various compounds, including flavones (apigenin, scutellarein), dihydrochalcone (phloretin), isoflavones (genistein, daidzein), flavanones (naringenin, glycyrrhizin), and flavanonols (dihydrokaempferol), leading to the formation of O-glycosides. The broad substrate specificity of these enzymes is noteworthy. This study provides valuable insights into the biosynthetic pathways of flavonoid glycosides in safflower. The discovery of CtOGT1 and CtOGT2 enhances our understanding of the enzymatic processes involved in synthesizing flavonoid glycosides in safflower, contributing to the overall comprehension of secondary metabolite biosynthesis in this plant species.