Validation of 12 Rapid Antigen Tests for the Detection of SARS-CoV-2.

The rapid identification SARS-CoV-2 virus has become the basis for the control of the COVID-19 outbreak. The rapid antigen tests for SARS-CoV-2 are quick, widely available, and inexpensive. Rapid antigen tests have gradually replaced the time-consuming and costly RT-PCR. Currently, although several RAT kits have been extensively used for the diagnosis of COVID-19, validity data are limited due to the inconsistent sensitivity and poor reproducibility. Meanwhile, WHO does not recommend specific commercial RAT kits. Therefore, it is crucial to establish a method to evaluate the effectiveness of different rapid antigen tests kits. This study aimed to develop an evaluation system for rapid antigen tests to provide an efficient and accurate technique for screening SARS-CoV-2 antigen detection kits. Given large number of rapid antigen tests kits available, this study only focused on those that are representative and commonely used in China. By minimzing biases through randomization, concealment, and blinding, we eventually found that the Test 1 had the lowest sensitivity and the Test VI had the highest sensitivity. This study provided an evaluation platform that can potentially serve as a reference for COVID-19 diagnostic strategies.

Cryo-EM Structure and Biochemical Analysis of the Human Chemokine Receptor CCR8.

The C-C motif chemokine receptor 8 (CCR8) is a class A G-protein-coupled receptor that has emerged as a promising therapeutic target in cancer and autoimmune diseases. In the present study, we solved the cryo-electron microscopy (cryo-EM) structure of the human CCR8-Gi complex in the absence of a ligand at 2.58 Å. Structural analysis and comparison revealed that our apo CCR8 structure undergoes some conformational changes and is similar to that in the CCL1-CCR8 complex structure, indicating an active state. In addition, the key residues of CCR8 involved in the recognition of LMD-009, a potent nonpeptide agonist, were investigated by mutating CCR8 and testing the calcium flux induced by LMD-009-CCR8 interaction. Three mutants of CCR8, Y1133.32A, Y1724.64A, and E2867.39A, showed a dramatically decreased ability in mediating calcium mobilization, indicating their key interaction with LMD-009 and key roles in activation. These structural and biochemical analyses enrich molecular insights into the agonism and activation of CCR8 and will facilitate CCR8-targeted therapy.

Deubiquitylase OTUD3 regulates integrated stress response to suppress progression and sorafenib resistance of liver cancer.

The integrated stress response (ISR) is activated in response to intrinsic and extrinsic stimuli, playing a role in tumor progression and drug resistance. The regulatory role and mechanism of ISR in liver cancer, however, remain largely unexplored. Here, we demonstrate that OTU domain-containing protein 3 (OTUD3) is a deubiquitylase of eukaryotic initiation factor 2α (eIF2α), antagonizing ISR and suppressing liver cancer. OTUD3 decreases interactions between eIF2α and the kinase EIF2ΑK3 by removing K27-linked polyubiquitylation on eIF2α. OTUD3 deficiency in mice leads to enhanced ISR and accelerated progression of N-nitrosodiethylamine-induced hepatocellular carcinoma. Additionally, decreased OTUD3 expression associated with elevated eIF2α phosphorylation correlates with the progression of human liver cancer. Moreover, ISR activation due to decreased OTUD3 expression renders liver cancer cells resistant to sorafenib, while the combined use of the ISR inhibitor ISRIB significantly improves their sensitivity to sorafenib. Collectively, these findings illuminate the regulatory mechanism of ISR in liver cancer and provide a potential strategy to counteract sorafenib resistance.

Double contrast-enhanced ultrasonography improves diagnostic accuracy of T staging compared with multi-detector computed tomography in gastric cancer patients.

BACKGROUND: Gastric cancer (GC) is the most common malignant tumor and ranks third for cancer-related deaths among the worldwide. The disease poses a serious public health problem in China, ranking fifth for incidence and third for mortality. Knowledge of the invasive depth of the tumor is vital to treatment decisions. AIM: To evaluate the diagnostic performance of double contrast-enhanced ultrasonography (DCEUS) for preoperative T staging in patients with GC by comparing with multi-detector computed tomography (MDCT). METHODS: This single prospective study enrolled patients with GC confirmed by preoperative gastroscopy from July 2021 to March 2023. Patients underwent DCEUS, including ultrasonography (US) and intravenous contrast-enhanced ultrasonography (CEUS), and MDCT examinations for the assessment of preoperative T staging. Features of GC were identified on DCEUS and criteria developed to evaluate T staging according to the 8th edition of AJCC cancer staging manual. The diagnostic performance of DCEUS was evaluated by comparing it with that of MDCT and surgical-pathological findings were considered as the gold standard. RESULTS: A total of 229 patients with GC (80 T1, 33 T2, 59 T3 and 57 T4) were included. Overall accuracies were 86.9% for DCEUS and 61.1% for MDCT (P < 0.001). DCEUS was superior to MDCT for T1 (92.5% vs 70.0%, P < 0.001), T2 (72.7% vs 51.5%, P = 0.041), T3 (86.4% vs 45.8%, P < 0.001) and T4 (87.7% vs 70.2%, P = 0.022) staging of GC. CONCLUSION: DCEUS improved the diagnostic accuracy of preoperative T staging in patients with GC compared with MDCT, and constitutes a promising imaging modality for preoperative evaluation of GC to aid individualized treatment decision-making.

Efficient Microbubble Trajectory Tracking in Ultrasound Localization Microscopy Using a Gated Recurrent Unit-Based Multitasking Temporal Neural Network.

Ultrasound Localization Microscopy (ULM), an emerging medical imaging technique, effectively resolves the classical trade-off between resolution and penetration inherent in traditional ultrasound imaging, opening up new avenues for noninvasive observation of the microvascular system. However, traditional microbubble tracking methods encounter various practical challenges. These methods typically entail multiple processing stages, including intricate steps like pairwise correlation and trajectory optimization, rendering real-time applications unfeasible. Furthermore, existing deep learning-based tracking techniques neglect the temporal aspects of microbubble motion, leading to ineffective modeling of their dynamic behavior. To address these limitations, this study introduces a novel approach called the Gated Recurrent Unit (GRU)-based Multitasking Temporal Neural Network (GRU-MT). GRU-MT is designed to simultaneously handle microbubble trajectory tracking and trajectory optimization tasks. Additionally, we enhance the nonlinear motion model initially proposed by Piepenbrock et al. to better encapsulate the nonlinear motion characteristics of microbubbles, thereby improving trajectory tracking accuracy. In this study, we perform a series of experiments involving network layer substitutions to systematically evaluate the performance of various temporal neural networks, including Recurrent Neural Networks (RNN), Long Short-Term Memory (LSTM), GRU, Transformer, and its bidirectional counterparts, on the microbubble trajectory tracking task. Concurrently, the proposed method undergoes qualitative and quantitative comparisons with traditional microbubble tracking techniques. The experimental results demonstrate that GRU-MT exhibits superior nonlinear modeling capabilities and robustness, both in simulation and in vivo dataset. Additionally, it achieves reduced trajectory tracking errors in shorter time intervals, underscoring its potential for efficient microbubble trajectory tracking. Model code is open-sourced at https://github.com/zyt-Lib/GRU-MT.

CCDC59 alleviates bleomycin-induced inflammation and pulmonary fibrosis by increasing SP-B and SP-C expression in mice.

BACKGROUND: Pulmonary fibrosis is a progressive disease with high incidence and poor prognosis. It is urgent to explore new therapeutic methods for pulmonary fibrosis. As a new treatment method, gene therapy has attracted more and more attention. CCDC59 is a transcriptional coactivator of SP-B and SP-C. Our study mainly aims to explore the effect of overexpression of CCDC59 gene in pulmonary fibrosis of mice. METHODS: CCDC59 overexpressing lentivirus was constructed and then concentrated. RT-qPCR, Western blotting, and immunofluorescence assays were used to detect the expression of CCDC59, SP-B and SP-C protein in cell line and lung tissues after infected with lentivirus. Immunohistochemical staining and hematoxylin-eosin staining assays were used to assess the degree of fibrosis and ELISA assay was used to detect the concentrations of inflammatory factors, SP-B, and SP-C in bronchoalveolar lavage fluid of mice. Dynamic changes of mice lung function at various time points were assessed by lung function test assay. HIPPO pathway and proliferation capacity of alveolar type II epithelial cells were evaluated by immunofluorescence staining and Western blotting. RESULTS: Results showed that endotracheal instillation of CCDC59 overexpressed lentivirus significantly alleviated bleomycin-induced inflammation and pulmonary fibrosis in mice. Overexpression of CCDC59 protein in type II alveolar epithelial cells can enhance the expression of SP-B and SP-C. Overexpression of CCDC59 protein significantly protected against pulmonary inflammatory response and improved lung function of mice. Overexpression of CCDC59 protein significantly alleviated the hyperactivation of HIPPO pathway and increased the proliferative capacity of type II alveolar epithelial cells in lung. CONCLUSION: CCDC59 can alleviate inflammation and pulmonary fibrosis in mice by upregulating the expression of SP-B and SP-C in type II alveolar epithelial cells and alleviating the hyperactivation of HIPPO pathway. Our study offers a new potential treatment for pulmonary fibrosis.

ACKR1+ Endothelial Cells Mediate Leukocyte Infiltration and Synergize with SFRP2/ASPN+ Fibroblasts to Promote Skin Fibrosis in Systemic Sclerosis.

BACKGROUND: Skin fibrosis is the most typical pathological manifestation of systemic sclerosis (SSc) and localized scleroderma (LS) with unclear etiology and few effective treatments. Though excessive collagen secretion by fibroblasts is the primary cause of skin fibrosis, many lines of evidence suggested that vascular damage was the initiating event and various cell types along with fibroblasts worked together to contribute to the pathogenesis of skin fibrosis. OBJECTIVES: We sought to explore the relationships between vascular endothelial cell lesions and immune cell infiltration, along with the cell-cell interactions among various cell types within the fibrotic skin ecosystem. METHODS: Single-cell RNA-seq (10x Genomics) was performed on skin biopsies of 3 healthy donors and 7 SSc patients in Chinese. The additional 3 localized scleroderma patients' data from NCBI database (GSE160536) were integrated by Harmony. CellChat package (v1.5.0) was applied to analyze cell communication network. Transwell assay and subcutaneous bleomycin (BLM) injection in mice were used to explore the role of ACKR1 on immune cell infiltration. Milo single-cell western blot was applied to show the activation of fibroblast subclusters. RESULTS: A total of 62,295 cells were obtained and subpopulations of stromal and immune cells were identified. Interaction network analysis revealed that multiple chemokines secreted by macrophages, pericytes, and pro-inflammatory fibroblasts could bind with Duffy antigen/receptor for chemokines (ACKR1), which is highly expressed on ACKR1+ endothelial cells of lesion skin. Transwell assay revealed that over-expressed ACKR1 in HUVEC facilitated leukocyte infiltration under the treatment of IL8. The BLM mice showed enhanced ACKR1 expression, massive immune cell infiltration, and fibrosis in skin, which could be attenuated by ACKR1 inhibition. Furthermore, infiltrated macrophages with TGFB1 or PDGFB high production could activate SFRP2/ASPN+ fibroblasts to contribute to excessive accumulation of extracellular matrix (ECM), and the SOX4-ASPN axis plays an important role in the TGF-ß signaling cascade and the etiology of skin fibrosis. CONCLUSIONS: Our results reveal that highly expressed ACKR1 in endothelial cells of fibrotic skin tissue promotes immune cell infiltration, and SFRP2/ASPN+ fibroblasts synergize to exacerbate skin fibrosis.

Effectiveness of sodium-glucose co-transporter 2 inhibitors on atrial fibrillation recurrence after catheter ablation: A systemic review and meta-analysis.

BACKGROUND: Studies have revealed the beneficial effects of sodium-glucose co-transporter 2 inhibitors (SGLT2i) for the treatment of heart failure (HF) regardless of the presence of diabetes. Besides, SGLT2i can decrease the incidence of atrial fibrillation (AF) in a broad population. However, the effects of SGLT2i on AF recurrence following catheter ablation (CA) remain uncertain. Therefore, this meta-analysis was undertaken to elucidate the effects of SGLT2i on AF recurrence after CA in AF patients. METHODS: A comprehensive search of PubMed, Embase, and Cochrane library was conducted for relevant studies, encompassing data from inception until March 20, 2024. The data were pooled using a fixed-effects model if the I2 value was <50%; otherwise, a random-effects model was adopted. RESULTS: One randomized controlled trial (RCT) and five observational studies involving 5623 patients with AF who underwent CA were included. SGLT2i treatment was associated with a significantly lower rate of AF recurrence (odds ratio [OR] = 0.45, 95% confidence interval [CI]: 0.31-0.66). Subgroup analysis demonstrated that patients treated with SGLT2i exhibited a lower incidence of AF recurrence compared to those treated with dipeptidyl peptidase-4 inhibitors (DPP4i). The favorable effects of SGLT2i on AF recurrence were more pronounced in male patients and patients with persistent AF. CONCLUSIONS: This meta-analysis provided evidence supporting the effectiveness of SGLT2i in reducing the risk of AF recurrence after CA in AF patients. SGLT2i may serve as an additional therapy option in this population.

Determinants of parental demand of human papillomavirus vaccination for adolescent daughters in China: Contingent valuation survey.

BACKGROUND: Several types of human papillomavirus (HPV) vaccines have been approved for use in adolescent girls in China. These vaccines are regulated as non-National Immunisation Program vaccines and are optional and generally fully self-paid by vaccinees. OBJECTIVE: To assess parents' demand for HPV vaccination by eliciting their willingness-to-pay for their adolescent daughters to be vaccinated against HPV and to examine the determinants of demand for HPV vaccination in China. METHODS: A contingent valuation survey was conducted across three cities in Shandong Province in eastern China. We selected 11 junior middle schools with different socioeconomic features and randomly selected 6 classes in each school, and questionnaires were distributed to all girls aged 12-16 in the 66 classes for their parents to complete. A payment card approach was used to elicit parental willingness-to-pay for HPV vaccination for their daughters. We also collected a wide array of socioeconomic and psychological variables and interval regressions were applied to examine the determinants of parental willingness-to-pay. RESULTS: A total of 1074 eligible parents who completed valid questions were included in analyses. Over 85% of parents believed HPV vaccines were, in general, necessary and beneficiary. However, only around 10% believed that their daughters would be infected by HPV. About 8% of parents would not accept HPV vaccine even if the vaccine were free mainly due to concerns about the potential side effects and vaccine safety and quality issues, and 27.37% would only accept the vaccine if it were free. The median willingness-to-pay was 300 CNY (42 USD). Several factors were positively correlated with higher willingness-to-pay: income, urban residence (relative to rural residence), mothers (relative to fathers), parents' beliefs about vaccine benefits, whether they should make decisions for their daughters, and whether their daughters would be susceptible to HPV. Though education-level was not significantly correlated with willingness-to-pay in the main regressions, a subgroup analysis revealed interesting dynamics in the relation between education and willingness-to-pay across different income-levels. CONCLUSIONS: There is a large gap between parents' willingness-to-pay and the market price of HPV vaccine for girls in China. Parents generally believed the HPV vaccines were beneficial and necessary but when asked for their daughters, most parents did not believe their daughters would be infected by HPV despite the high prevalence in China. Future focus should be on ensuring the provision of accurate health information about HPV prevalence, vaccine quality, and safety to promote vaccine uptake, and promotional efforts tailored to different income groups might yield better effects. Government involvement in negotiating more widely acceptable and affordable prices or subsidising may be necessary for protecting high-risk population groups.

Stabilized Hf-doped Ti/Sb-SnO2 electrode for efficient degradation of tetracycline.

The electrochemical advanced oxidation process (EAOP) has shown significant promise in the field of refractory organic wastewater treatment due to its high efficiency and environmentally friendly nature. In this study, Ti/Sb-SnO2 electrodes with varying proportions of Hf were prepared using the sol-gel method. The addition of Hf transformed the original collapsing and broken surface into a flat and regular surface. The results demonstrated that Ti/Sb-SnO2-Hf electrode doped with 6% Hf exhibited a higher oxygen evolution potential (OEP) and excellent stability. The OEP increased from 2.315 V without Hf-doping to 2.482 V, and the corresponding actual life was 321.05% higher than that without Hf. The current density (5-40 mA·cm-2), electrolyte concentration (0.02-0.2 mol·L-1), pH (3-11), and initial pollutant concentration (5-80 mg·L-1) were evaluated to confirm the tetracycline (TC) degradation characterization of Ti/Sb-SnO2-6%Hf electrodes. It was concluded that under the optimal degradation conditions, the removal rate of TC could reach 99.66% within 2 h. The degradation of TC follows first-order reaction kinetics. The oxidative degradation of TC was achieved through indirect oxidation, with ·OH playing a dominant role. TC's electrochemical oxidation degradation pathway has been proposed: Based on LC-MS results, three main pathways are speculated. During the electrocatalytic oxidation process, decarboxylation, deamidation, and ring-opening reactions occur under ·OH attack, producing intermediate compounds with m/z values of 427, 433, 350, 246, 461, 424, 330, 352, 309, 263, and 233. These intermediates are further oxidized to intermediate compounds with an m/z value of 218. This work introduces a new efficient anode electrochemical catalyst for the degradation of TC, providing a strategy for industrial applications.

The Association of High Arousal Threshold with Hypertension and Diabetes in Obstructive Sleep Apnea.

Objective: Compared to low arousal threshold (AT), high AT is an easily overlooked characteristic for obstructive sleep apnea (OSA) severity estimation. This study aims to evaluate the relationship between high AT, hypertension and diabetes in OSA, compared to those with apnea-hypopnea index (AHI). Methods: A total of 3400 adults diagnosed with OSA were retrospectively recruited. Propensity score matching (PSM) was conducted to further categorize these patients into the low and high AT groups based on the strategy established by previous literature. The different degrees of AHI and quantified AT (AT score) were subsequently measured. The correlation of AT and AHI with the occurrence of various comorbidities in OSA was estimated by logistic regression analysis with odds ratio (OR). Results: After PSM, 938 pairs of patients arose. The median AT score of high and low AT group was 21.7 and 12.2 scores, and the adjusted OR of high AT for hypertension and diabetes was 1.31 (95% CI = 1.07-1.62, P < 0.01) and 1.45 (95% CI = 1.01-2.08, P < 0.05), respectively. Compared to low AT score group, the OR significantly increased in patients with very high AT score (30 ≤ AT score), especially for diabetes (OR = 1.79, 95% CI = 1.02-3.13, P < 0.05). The significant association was not observed in AHI with increasing prevalent diabetes. Conclusion: Higher AT is significantly associated with increased prevalence of hypertension and diabetes in patients with OSA. Compared with AHI, AT score is a potentially comprehensive indicator for better evaluating the relationship between OSA and related comorbidities.

Crystalline silica-induced endoplasmic reticulum stress promotes the pathogenesis of silicosis by augmenting proinflammatory interstitial pulmonary macrophages.

Crystalline silica (CS) particles are ubiquitously present in the environment, particularly in occupational settings, and exposure to respirable CS causes silicosis, imposing a significant disease burden. However, the pathogenesis of silicosis remains unclear. Exposure to external stimuli, such as CS, leads to the accumulation of unfolded proteins and triggers endoplasmic reticulum (ER) stress, disrupting tissue immune homeostasis and accelerating pathological progression. While pulmonary macrophages phagocytose CS particles to initiate the immune response, the role of ER stress in this process is unknown. Herein, we used a murine model of silicosis to simulate the pathological progression from acute inflammation to fibrosis in silicosis and conducted in vivo pharmacological inhibition of ER stress to explore the underlying mechanism. Using flow cytometry, we further classified pulmonary macrophages into monocyte-like macrophages (monocytes), interstitial macrophages (IMs), and alveolar macrophages (AMs). Our results showed that CS-induced ER stress primarily contributed to the augmentation of IMs and thereby exerted a significant impact on pulmonary macrophages. Despite coexpressing M1- and M2-like markers, IMs predominantly exhibited an M1-like polarization state and played a proinflammatory role by expressing the cytokines pro-IL-1ß and TNF-α during the pathological progression of silicosis. Additionally, IMs recruited by CS-induced ER stress also exhibited high expression of MHCII and exerted active immunomodulatory effects. Overall, our study demonstrates that ER stress induced by CS particles triggers a proinflammatory immune microenvironment dominated by IMs and reveals novel insights into the pulmonary toxicological effects of CS particles.

Fabrication of zein-coated brush-like silica nanocarriers for high foliage deposition and responsive release of pesticide.

Responsive release systems have received extensive attention to enhance pesticide utilization efficiency and reduce environmental pollution. In this study, pH/GSH dual responsive release system based on brush-like silica (bSiO2) carriers was constructed to enhance the utilization of pesticides. The bSiO2 carriers present core-shell structure, length of 550 nm, diameter of 350 nm and shell thickness of 100 nm. The carrier had a high pesticide loading (20.0 %, w/w) for dinotefuran (Din). After loading Din, zein was covalently linked with cysteine-bridge to seal the loaded pesticides (namely Din@bSiO2@Zein). The Din@bSiO2@Zein exhibited superior foliar affinity, retention and photostability, and retention rate still remain above 95 % with 220 min UV irradiation. Din@bSiO2@Zein displayed pH/GSH responsive release and the cumulative release within 92 h was up to 81 % under pH=9/CGSH=6 mM, mimicking the microenvironment of lepidopteran. The Din@bSiO2@Zein possessed good control efficacy against Plutella xylostella. Appreciably, Din@bSiO2@Zein could be transported bi-directionally to various regions of tobacco plants within 24 h, which had potential to promote pesticide efficacy. This work offers a strategy to minimize the pesticide dosage and encourage sustainable agricultural development.

ABHD5 regulates midgut-specific lipid homeostasis in Bombyx mori.

Lipids are an important energy source and are utilized as substrates for various physiological processes in insects. Comparative gene identification 58 (CGI-58), also known as α/ß hydrolase domain-containing 5 (ABHD5), is a highly conserved and multifunctional gene involved in regulating lipid metabolism and cellular energy balance in many organisms. However, the biological functions of ABHD5 in insects are poorly understood. In the current study, we describe the identification and characterization of the ABHD5 gene in the lepidopteran model insect, Bombyx mori. The tissue expression profile investigated using quantitative reverse transcription polymerase chain reaction (RT-qPCR) reveals that BmABHD5 is widely expressed in all tissues, with particularly high levels found in the midgut and testis. A binary transgenic CRISPR/Cas9 system was employed to conduct a functional analysis of BmABHD5, with the mutation of BmABHD5 leading to the dysregulation of lipid metabolism and excessive lipid accumulation in the larval midgut. Histological and physiological analysis further reveals a significant accumulation of lipid droplets in the midgut of mutant larvae. RNA-seq and RT-qPCR analysis showed that genes related to metabolic pathways were significantly affected by the absence of BmABHD5. Altogether, our data prove that BmABHD5 plays an important role in regulating tissue-specific lipid metabolism in the silkworm midgut.

ß-Cyclodextrin/carbon dots-grafted cellulose nanofibrils hydrogel for enhanced adsorption and fluorescence detection of levofloxacin.

In this study, a novel hydrogel, ß-cyclodextrin/carbon dots-grafted cellulose nanofibrils hydrogel (ßCCH), was fabricated for removal and fluorescence determination of levofloxacin (LEV). A comprehensive analysis was performed to characterize its physicochemical properties. Batch adsorption experiments were conducted, revealing that ßCCH reached a maximum adsorption capacity of 1376.9 mg/g, consistent with both Langmuir and pseudo-second-order models, suggesting that the adsorption process of LEV on ßCCH was primarily driven by chemical adsorption. The removal efficiency of ßCCH was 99.2 % under the fixed conditions (pH: 6, initial concentration: 20 mg/L, contact time: 300 min, temperature: 25 °C). The removal efficiency of ßCCH for LEV still achieved 97.3 % after five adsorption-desorption cycles. By using ßCCH as a fluorescent probe for LEV, a fast and sensitive method was established with linear ranges of 1-120 mg/L and 0.2-1.0 µg/L and a limit of detection (LOD) as low as 0.09 µg/L. The viability of ßCCH was estimated based on the economic analysis of the synthesis process and the removal of LEV, demonstrating that ßCCH was more cost-effective than commercial activated carbon. This study provides a novel approach for preparing a promising antibiotic detection and adsorption material with the advantages of stability, and cost-effectiveness.

Preliminary analysis on the characteristics of light absorption coefficients in typical rivers of different river basins across China.

As a vital constituent of water's optical properties, the absorption coefficients influence the distribution of underwater light field, consequently impacting the structures and functional patterns of riverine ecosystems. In this study, the light absorption of non-algal particulates (ad(λ), m-1), phytoplankton (aph(λ), m-1) and CDOM (ag(λ), m-1) of 380 water samples collected from 133 rivers in eight external river basins across China from 2013 to 2023 were examined to determine the optical absorption characteristics. Results showed significant differences in ad(λ), aph(λ) and ag(λ) across different basins. ① The water bodies of eight basins can be categorized into 5 dominant types of absorption coefficients. ② In eastern China, ag(440) exhibited a northeast-high and southwest-low spatial distribution pattern. The Songliao River Basin had the highest ag(440) than other basins. The higher slope S of ag(λ) in rivers compared to lakes and reservoirs confirm river water primarily derive CDOM from external sources, distinguishing them from lakes and reservoirs. ③ The Huaihe and Haihe River Basins had higher ad(440) and aph(440) values, primarily due to lower terrain and human activities, leading to the accumulation of suspended particles and nutrients. And soil erosion from the Loess Plateau caused significant differences in ad(440) between the upper and middle reaches of the Yellow River Basin. These findings hold significant implications for understanding the optical characteristics of rivers in China.

A highly sensitive fluorescence sensor for tobacco mosaic virus RNA based on DSN cycle and ARGET ATRP double signal amplification.

Early and sensitive detection of tobacco mosaic virus (TMV) is of great significance for improving crop yield and protecting germplasm resources. Herein, we constructed a novel fluorescence sensor to detect TMV RNA (tRNA) through double strand specific nuclease (DSN) cycle and activator regenerative electron transfer atom transfer radical polymerization (ARGET ATRP) dual signal amplification strategy. The hairpin DNA complementarily paired with tRNA was used as a recognition unit to specifically capture tRNA. By the double-stranded DNA hydrolyzed with DSN, tRNA is released to open more hairpin DNA, and more complementary DNA (cDNA) is bound to the surface of the magnetic beads (MBs) to achieve the first amplification. After binding with the initiator, the cDNA employed ARGET ATRP to attach more fluorescent signal molecules to the surface of MBs, thus achieving the second signal amplification. Under the optimal experimental conditions, the logarithm of fluorescence intensity versus tRNA concentration showed a good linear relationship in the range of 0.01-100 pM, with a detection limit of 1.03 fM. The limit of detection (LOD) was calculated according to LOD = 3 N/S. Besides, the sensor showed good reproducibility and stability, which present provided new method for early and highly sensitive detection for plant viruses.

A novel three-layer module BoMYB1R1-BoMYB4b/BoMIEL1-BoDFR1 regulates anthocyanin accumulation in kale.

Anthocyanin is an important pigment responsible for plant coloration and beneficial to human health. Kale (Brassica oleracea var. acephala), a primary cool-season flowers and vegetables, is an ideal material to study anthocyanin biosynthesis and regulation mechanisms due to its anthocyanin-rich leaves. However, the underlying molecular mechanism of anthocyanin accumulation in kale remains poorly understood. Previously, we demonstrated that BoDFR1 is a key gene controlling anthocyanin biosynthesis in kale. Here, we discovered a 369-bp InDel variation in the BoDFR1 promoter between the two kale inbred lines with different pink coloration, which resulted in reduced transcriptional activity of the BoDFR1 gene in the light-pink line. With the 369-bp insertion as a bait, an R2R3-MYB repressor BoMYB4b was identified using the yeast one-hybrid screening. Knockdown of the BoMYB4b gene led to increased BoDFR1 expression and anthocyanin accumulation. An E3 ubiquitin ligase, BoMIEL1, was found to mediate the degradation of BoMYB4b, thereby promoting anthocyanin biosynthesis. Furthermore, the expression level of BoMYB4b was significantly reduced by light signals, which was attributed to the direct repression of the light-signaling factor BoMYB1R1 on the BoMYB4b promoter. Our study revealed that a novel regulatory module comprising BoMYB1R1, BoMIEL1, BoMYB4b, and BoDFR1 finely regulates anthocyanin accumulation in kale. The findings aim to establish a scientific foundation for genetic improvement of leaf color traits in kale, meanwhile, providing a reference for plant coloration studies.

Exoskeleton rehabilitation robot training for balance and lower limb function in sub-acute stroke patients: a pilot, randomized controlled trial.

PURPOSE: This pilot study aimed to investigate the effects of REX exoskeleton rehabilitation robot training on the balance and lower limb function in patients with sub-acute stroke. METHODS: This was a pilot, single-blind, randomized controlled trial. Twenty-four patients with sub-acute stroke (with the course of disease ranging from 3 weeks to 3 months) were randomized into two groups, including a robot group and a control group. Patients in control group received upright bed rehabilitation (n = 12) and those in robot group received exoskeleton rehabilitation robot training (n = 12). The frequency of training in both groups was once a day (60 min each) for 5 days a week for a total of 4 weeks. Besides, the two groups were evaluated before, 2 weeks after and 4 weeks after the intervention, respectively. The primary assessment index was the Berg Balance Scale (BBS), whereas the secondary assessment indexes included the Fugl-Meyer Lower Extremity Motor Function Scale (FMA-LE), the Posture Assessment Scale for Stroke Patients (PASS), the Activities of Daily Living Scale (Modified Barthel Index, MBI), the Tecnobody Balance Tester, and lower extremity muscle surface electromyography (sEMG). RESULTS: The robot group showed significant improvements (P < 0.05) in the primary efficacy index BBS, as well as the secondary efficacy indexes PASS, FMA-LE, MBI, Tecnobody Balance Tester, and sEMG of the lower limb muscles. Besides, there were a significant differences in BBS, PASS, static eye-opening area or dynamic stability limit evaluation indexes between the robotic and control groups (P < 0.05). CONCLUSIONS: This is the first study to investigate the effectiveness of the REX exoskeleton rehabilitation robot in the rehabilitation of patients with stroke. According to our results, the REX exoskeleton rehabilitation robot demonstrated superior potential efficacy in promoting the early recovery of balance and motor functions in patients with sub-acute stroke. Future large-scale randomized controlled studies and follow-up assessments are needed to validate the current findings. CLINICAL TRIALS REGISTRATION: URL: https://www.chictr.org.cn/index.html.Unique identifier: ChiCTR2300068398.