Probiotics relieve perioperative postoperative cognitive dysfunction induced by cardiopulmonary bypass through the kynurenine metabolic pathway.

Postoperative cognitive dysfunction (POCD) has become the popular critical post-operative consequences, especially cardiopulmonary bypass surgery, leading to an increased risk of mortality. However, no therapeutic effect about POCD. Probiotics are beneficial bacteria living in the gut and help to reduce the risk of POCD. However, the detailed mechanism is still not entirely known. Therefore, our research aims to uncover the effect and mechanism of probiotics in relieving POCD and to figure out the possible relationship between kynurenine metabolic pathway. 36 rats were grouped into three groups: sham operated group (S group, n = 12), Cardiopulmonary bypass group (CPB group, n = 12), and probiotics+CPB (P group, n = 12). After CPB model preparation, water maze test and Garcia score scale was performed to identify the neurological function. Immunofluorescence and Hematoxylin and eosin staining has been used for hippocampal neurons detection. Brain injury related proteins, oxidative stress factors, and inflammatory factors were detected using enzyme-linked immunosorbent assays (ELISA). Neuronal apoptosis was detected by TdT-mediated dUTP nick end-labeling (TUNEL) staining and western blot. High-performance liquid chromatography/mass spectrometry (HPLC/MS) was performed to detect the key factors of the kynurenine metabolic pathway. Our results demonstrated that probiotics improved neurological function of post-CPB rats. The administration of probiotics ameliorated memory and learning in spatial terms CPB rats (P < 0.05). Hematoxylin and eosin (H&E) staining data, S-100ß and neuron-specific enolase (NSE) data convinced that probiotics agonists reduced brain damage in CPB rats (P < 0.05). Moreover, probiotics regulated inflammatory factors, meanwhile attenuated hippocampal neuronal apoptosis. Probiotics alleviated POCD in rats with CPB through regulation of kynurenine metabolic signaling pathway.

Elevated type I IFN signalling directly affects CD8+ T-cell distribution and autoantigen recognition of the skeletal muscles in active JDM patients.

The link between type I IFN and adaptive immunity, especially T-cell immunity, in JDM still remained largely unclear. This study aimed to understand the effect of elevated type I IFN signaling on CD8+ T cell-associated muscle damage in juvenile dermatomyositis (JDM). This study used flow cytometry (FC) and RT‒PCR were used to examine the circulating cell ratio and type I IFN response. And scRNA-seq was used to examine peripheral immunity in 6 active JDM patients, 3 stable JDM patients, 3 juvenile IMNM patients and 3 age-matched healthy children. In vivo validation experiments were conducted using a mouse model induced by STING agonists and an experimental autoimmune myositis model (EAM). In vitro experiments were conducted using isolated CD8+ T-cells from JDM patients and mice. We found that active JDM patients showed an extensive type I IFN response and a decreased CD8+ T-cell ratio in the periphery (P < 0.05), which was correlated with muscle involvement (P < 0.05). Both new active JDM patients and all active JDM patients showed decreased CD8+ TCM cell ratios compared with age and gender matched stable JDM patients (P < 0.05). Compared with new pediatirc systemic lupus erythematosus (SLE) patients, new active JDM patients displayed decreased CD8+ T-cell and CD8+ TCM cell ratios (P < 0.05). Active JDM patient skeletal muscle biopsies displayed an elevated type I IFN response, upregulated MHC-I expression and CD8+ T-cell infiltration, which was validated in EAM mice. sc-RNAseq demonstrated that type I IFN signalling is the kinetic factor of abnormal differentiation and enhances the cytotoxicity of peripheral CD8+ T cells in active JDM patients, which was confirmed by in vivo and in vitro validation experiments. In summary, the elevated type I IFN signalling affected the differentiation and function of CD8+ T cells in active JDM patients. Skeletal muscle-infiltrating CD8+ T cells might migrate from the periphery under the drive of type I IFN and increased MHC I signals. Therapies targeting autoantigen-specific CD8+ T cells may represent a potential new treatment direction.

A rapid, equipment-free method for detecting avirulence genes of Pyricularia oryzae using a lateral flow strip-based RPA assay.

Rice blast, caused by Pyricularia oryzae, is one of the most destructive rice diseases worldwide. Using resistant rice varieties is the most cost-effective way to control rice blast. Consequently, it is critical to monitor the distribution frequency of avirulence genes in rice planting field to facilitate the breedings of resistant rice varieties. In this study, we established a rapid RPA-LFD detection system for the identification of AvrPik, Avr-Piz-t and Avr-Pi9. The optimized reaction temperature and duration were 37°C and 20 min, indicating that the reaction system could be initiated by body temperature without relying on any precision instruments. Specificity analysis showed that the primer and probe combinations targeting three Avr genes exhibited a remarkable specificity for at genus-level detection. Under the optimized condition, the lower detected thresholds of AvrPik, Avr-Piz-t and Avr-Pi9 were 10 fg/µl, 100 fg/µl and 10 pg/µl, respectively. Notably, the detection sensitivity of three Avr genes was much higher than that of PCR. In addition, we also successfully detected the presence of AvrPik, Avr-Piz-t and Avr-Pi9 in the leaf and panicle blast lesions with the RPA-LFD detection system. In particular, the genomic DNA was extracted using the simpler PEG-NaOH rapid extraction method. In summary, we developed the RPA detection system for AvrPik, Avr-Pi9 and Avr-Piz-t, combined with the PEG-NaOH rapid DNA extraction method. The innovative approach achieved rapid, real-time and accurate detection of three Avr genes in the field, which is helpful to understand the distribution frequency of the three Avr genes in the field and provide theoretical reference for the scientific layout of rice resistant varieties.

Association between physical activity and depression in adult prescription opioid users: A cross-sectional analysis based on NHANES 2007-2018.

OBJECTIVE: This study was designed to examine the association between physical activity (PA) and depression among adult prescription opioid users. METHOD: Data of adults who recently took prescription opioids were collected from NHANES 2007-2018. Participants were divided into two groups according to whether PA in each domain was ≥600 MET-min/week. According to weekly activity frequency, recreational physical activity (RPA) was divided into inactivity, insufficient activity, weekend warrior (WW), and regular activity. PHQ-9 scores ≥10 were identified as depression. RESULTS: RPA of ≥600 MET-min/week was associated with a 40% (OR: 0.60, 95%CI: 0.38-0.96, P = 0.032) reduction in the risk of depression. Restricted Cubic Spline plots found a nonlinear dose-response relationship between RPA and depression (P = 0.045), and the turning point of depression risk was around 600 MET-min/week. There was no significant difference in the risk of depression between the WW and inactivity groups (OR: 0.65, 95%CI: 0.25-1.72, P = 0.382). The regular activity group had an 45% (OR: 0.55, 95%CI: 0.31-0.99, P = 0.046)lower risk for depression than the inactivity group. CONCLUSION: Only regular RPA is associated with a reduced risk of depression, and RPA showed a nonlinear dose-response relationship. The antidepressant effect of the WW is not significant.

The Ras GTPase-activating protein UvGap1 orchestrates conidiogenesis and pathogenesis in the rice false smut fungus Ustilaginoidea virens.

Ras GTPase-activating proteins (Ras GAPs) act as negative regulators for Ras proteins and are involved in various signalling processes that influence cellular functions. Here, the function of four Ras GAPs, UvGap1 to UvGap4, was identified and analysed in Ustilaginoidea virens, the causal agent of rice false smut disease. Disruption of UvGAP1 or UvGAP2 resulted in reduced mycelial growth and an increased percentage of larger or dumbbell-shaped conidia. Notably, the mutant ΔUvgap1 completely lost its pathogenicity. Compared to the wild-type strain, the mutants ΔUvgap1, ΔUvgap2 and ΔUvgap3 exhibited reduced tolerance to H2 O2 oxidative stress. In particular, the ΔUvgap1 mutant was barely able to grow on the H2 O2 plate, and UvGAP1 was found to influence the expression level of genes involved in reactive oxygen species synthesis and scavenging. The intracellular cAMP level in the ΔUvgap1 mutant was elevated, as UvGap1 plays an important role in maintaining the intracellular cAMP level by affecting the expression of phosphodiesterases, which are linked to cAMP degradation in U. virens. In a yeast two-hybrid assay, UvRas1 and UvRasGef (Ras guanyl nucleotide exchange factor) physically interacted with UvGap1. UvRas2 was identified as an interacting partner of UvGap1 through a bimolecular fluorescence complementation assay and affinity capture-mass spectrometry analysis. Taken together, these findings suggest that the UvGAP1-mediated Ras pathway is essential for the development and pathogenicity of U. virens.

Chinese herbal medicine for post-viral fatigue: A systematic review of randomized controlled trials.

BACKGROUND: Fatigue is a common symptom after viral infection. Chinese herbal medicine (CHM) is thought to be a potential effective intervention in relieving fatigue. PURPOSE: To assess the effectiveness and safety of CHM for the treatment of post-viral fatigue. STUDY DESIGN: Systematic review and meta-analysis of randomized controlled trials (RCTs). METHODS: The protocol of this systematic review was registered on PROSPERO (CRD42022380356). Trials reported changes of fatigue symptom, which compared CHM to no treatment, placebo or drugs, were included. Six electronic databases and three clinical trial registration platforms were searched from inception to November 2023. Literature screening, data extraction, and risk bias assessment were independently carried out by two reviewers. Quality of the included trials was evaluated using Cochrane risk of bias tool, and the certainty of the evidence was evaluated using GRADE. The meta-analysis was performed using Review Manager 5.4, mean difference (MD) and its 95% confidence interval (CI) was used for estimate effect of continuous data. Heterogeneity among trials was assessed through I2 value. RESULTS: Overall, nineteen studies with 1921 patients were included. Results of individual trial or meta-analysis showed that CHM was better than no treatment (MD = -0.80 scores, 95%CI -1.43 to -0.17 scores, P = 0.01, 60 participants, 1 trial), placebo (MD = -1.90 scores, 95%CI -2.38 to -1.42 scores, P<0.00001, 184 participants, 1 trial), placebo on basis of rehabilitation therapy (MD = -14.90 scores, 95%CI -24.53 to -5.27 scores, P = 0.02, 118 participants, 1 trial) or drugs (MD = -0.38 scores, 95%CI -0.48 to -0.27 scores, I2 = 0%, P<0.00001, 498 participants, 4 trials) on relieving fatigue symptoms assessing by Traditional Chinese Medicine fatigue scores. Trials compared CHM plus drugs to drugs alone also showed better effect of combination therapy (average MD = -0.56 scores). In addition, CHM may improve the percentage of CD4 T lymphocytes and reduce the level of serum IL-6 (MD = -14.64 scores, 95%CI 18.36 to -10.91 scores, I2 = 0%, P<0.00001, 146 participants, 2 trials). CONCLUSION: Current systematic review found that the participation of CHM can improve the symptoms of post-viral fatigue and some immune indicators. However, the safety of CHM remains unknown and large sample, high quality multicenter RCTs are still needed in the future.

The 90% effective concentration of alfentanil combined with 0.075% ropivacaine for epidural labor analgesia: a single-center, prospective, double-blind sequential allocation biased-coin design.

PURPOSE: More literature studies have reported that alfentanil is safe and effective for labor analgesia. However, there is no unified consensus on the optimal dosage of alfentanil used for epidural analgesia. This study explored the concentration at 90% of minimum effective concentration (EC90) of alfentanil combined with 0.075% ropivacaine in patients undergoing epidural labor analgesia to infer reasonable drug compatibility and provide guidance for clinical practice. METHODS: In this prospective, single-center, double-blind study, a total of 45 singleton term primiparas with vaginal delivery who volunteered for epidural labor analgesia were recruited. The first maternal was administered with 3 µg/mL alfentanil combined with 0.075% ropivacaine with the infusion of 10 mL of the mixture every 50 min at a background dose of 3 mL/h. In the absence of PCEA, a total of 15 mL of the mixture is injected per hour. The subsequent alfentanil concentration was determined on the block efficacy of the previous case, using an up-down sequential allocation with a bias-coin design. 30 min after epidural labor analgesia, the block of patient failed with visual analog score (VAS) > 3, the alfentanil concentration was increased in a 0.5 µg/mL gradient for the next patient, while the block was successful with VAS ≤ 3, the alfentanil concentration was remained or decreased in a gradient according to a randomized response list for the next patient. EC90 and 95% confidence interval were calculated by linear interpolation and prediction model with R statistical software. RESULTS: In this study, the estimated EC90 of alfentanil was 3.85 µg/mL (95% confidence interval, 3.64-4.28 µg/mL). CONCLUSION: When combined with ropivacaine 0.075%, the EC90 of alfentanil for epidural labor analgesia is 3.85 µg/mL in patients undergoing labor analgesia.

The efficacy and safety of diterpene ginkgolides meglumine injection for cerebral infarction: A meta-analysis of randomized controlled trials.

OBJECTIVE: To systemically evaluate the efficacy and safety of diterpene ginkgolides meglumine injection (DGMI) on cerebral infarction (CI). METHODS: Comprehensively collect randomized controlled trials of DGMI in the treatment of CI in 7 databases including Embase, PubMed, the Cochrane Library, the China National Knowledge Infrastructure Database, the WanFang Database, the China Science and Technology Journal Database, and the China Biology Medicinedisc as of January 2023. The studies were screened according to the inclusion and exclusion criteria and evaluated according to the criteria recommended by the Cochrane Handbook, then RevMan 5.3, Stata 12.0 software were used for Meta-analysis. RESULTS: A total of 22 randomized controlled trials with 2194 patients were included. Meta analysis showed that: the total effective rate of treatment (relative risk = 1.29, 95% confidence interval (1.21, 1.38), P < .001), National Institute of Health stroke scale score, Barthel index and Modified Rankin Scale were better in DGMI group than in Conventional Western Medicine Treatment group. The included studies reported 42 adverse events, 25 of which belonged to DGMI groups. CONCLUSION: Available evidence suggested that DGMI can significantly improve the clinical efficiency in the treatment of CI. DGMI is an ideal treatment for CI, which has high clinical application value.

Nitrogen Addition and Heterotroph Exclusion Affected Plant Species Diversity-Biomass Relationship by Affecting Plant Functional Traits.

(1) Background: Heterotrophs can affect plant biomass and alter species diversity-productivity relationships. However, these studies were conducted in systems with a low nitrogen (N) availability, and it is unclear how heterotroph removal affects the relationship between plant species diversity and productivity in different N habitats. (2) Methods: Three typical understory herbaceous plants were selected to assemble the plant species diversity (three plant species richness levels (1, 2, and 3) and seven plant species compositions), and the control, insecticide, fungicide, and all removal treatments were performed at each plant species diversity level in systems with or without N addition treatments. (3) Results: In systems without N addition, the insecticide treatment increased the plant aboveground biomass, total biomass, and leaf area, while the fungicide treatment reduced the plant belowground biomass, root length, and root tip number; the presence of Bidens pilosa increased the plant aboveground biomass. Similarly, the presence of Bletilla striata increased the plant belowground biomass and root diameter under each heterotroph removal treatment. In systems with N addition, all removal treatments reduced the plant belowground biomass and increased the plant leaf area; the presence of B. pilosa significantly increased the plant aboveground biomass, total biomass, and root length under each heterotroph removal treatment. The presence of B. striata significantly increased the plant belowground biomass and leaf area under insecticide and fungicide treatments. (4) Conclusions: Heterotroph removal alters the plant species diversity-biomass relationship by affecting the plant functional traits in systems with different N availabilities. The impact of biodiversity at different trophic levels on ecosystem functioning should be considered under the background of global change.

UvVelC is important for conidiation and pathogenicity in the rice false smut pathogen Ustilaginoidea virens.

Rice false smut disease is one of the most significant rice diseases worldwide. Ustilaginoidea virens is the causative agent of this disease. Although several developmental and pathogenic genes have been identified and functionally analyzed, the pathogenic molecular mechanisms of U. virens remain elusive. The velvet family regulatory proteins are involved in fungal development, conidiation, and pathogenicity. In this study, we demonstrated the function of the VelC homolog UvVELC in U. virens. We identified the velvet family protein UvVELC and characterized its functions using a target gene deletion-strategy. Deletion of UvVELC resulted in conidiation failure and pathogenicity. The UvVELC expression levels during infection suggested that this gene might be involved in the early infection process. UvVELC is also important in resistance to abiotic stresses, the utilization efficiency of glucose, stachyose, raffinose, and other sugars, and the expression of transport-related genes. Moreover, UvVELC could physically interact with UvVEA in yeast, and UvVELC/UvVEA double-knockout mutants also failed in conidiation and pathogenicity. These results indicate that UvVELC play a critical role in the conidiation and pathogenicity in U. virens. Functional analysis indicated that UvVELC-mediated conidiation and nutrient acquisition from rice regulates the pathogenicity of U. virens. Understanding the function of the UvVELC homolog could provide a potential molecular target for controlling rice false smut disease.

Rapid quality evaluation and geographical origin recognition of ginger powder by portable NIRS in tandem with chemometrics.

Ginger powder is an important spice that is susceptible to improper sales such as adulteration or geographical fraud. In this study, a portable near infrared spectroscopy was used to quantitatively predict the 6-gingerol content, an important quality index of ginger, as well as to identify the gingers from three origins in China. Specifically, the optimal preprocessing method was first investigated by comparing the predictions of models. Then three feature variable selection methods including PCA, CARS, and RFrog, on the quantitative analysis of 6-gingerol were also compared, respectively. After comparison, the PLS model established on the S-G combined with SNV preprocessing outperformed the others. The PLS regression of 6-gingerol with variables selected by RFrog possessed the Rc2 of 0.9463, Rp2 of 0.9497, and the RPD of 4.2257, respectively. Moreover, the results further verified that the LDA model by SPA variables extraction successfully identify gingers from different origins with 100 % accuracy.

Environmental heterogeneity affecting spatial distribution of phytoplankton community structure and functional groups in a large eutrophic lake, Lake Chaohu, China.

The growth and development of phytoplankton are influenced by physico-chemical parameters, which can also affect the spatial distribution of phytoplankton community structure. However, it is unclear whether environmental heterogeneity caused by multiple physico-chemical factors can affect the spatial distribution of phytoplankton and its functional groups. In this study, we investigated the seasonal variation and spatial distribution of phytoplankton community structure and its relationships with environmental factors in Lake Chaohu from August 2020 to July 2021. We recorded a total of 190 species from 8 phyla, which were divided into 30 functional groups, including 13 dominating functional groups. The average annual phytoplankton density and biomass were (5.46 ± 7.17) × 107 cells/L and 4.80 ± 4.61 mg/L, respectively. The density and biomass of phytoplankton were higher in summer ((14.64 ± 20.34) × 107 cells/L, 10.61 ± 13.16 mg/L) and autumn ((6.79 ± 3.97) × 107 cells/L, 5.57 ± 2.40 mg/L), with the M and H2 of dominant functional groups. The dominant functional groups were N, C, D, J, MP, H2, and M in spring, whereas functional groups C, N, T, and Y dominated in winter. The distribution of phytoplankton community structure and dominant functional groups exhibited significant spatial heterogeneity in the lake, which was consistent with the environmental heterogeneity of the lake and could be classified into four locations. Location I had higher phytoplankton density and biomass than the other three locations. Additionally, dominant functional groups M, C, and H2 were present throughout the lake, and all 13 dominant functional groups were observed in Location II. Our findings suggest that environmental heterogeneity is a key factor influencing the spatial distribution of phytoplankton functional groups in Lake Chaohu.

The triglyceride catabolism regulated by a serine/threonine protein phosphatase, Smek1, is required for development and plant infection in Magnaporthe oryzae.

Magnaporthe oryzae is a pathogenic fungus that seriously harms rice production. Phosphatases and carbon metabolism play crucial roles in the growth and development of eukaryotes. However, it remains unclear how serine/threonine phosphatases regulate the catabolism of triglycerides, a major form of stored lipids. In this study, we identified a serine/threonine protein phosphatase regulatory subunit, Smek1, which is required for the growth, conidiation, and virulence of M. oryzae. Deletion of SMEK1 led to defects in the utilization of lipids, arabinose, glycerol, and ethanol. In glucose medium, the expression of genes involved in lipolysis, long-chain fatty acid degradation, ß-oxidation, and the glyoxylate cycle increased in the Δsmek1 mutant, which is consistent with ΔcreA in which a carbon catabolite repressor CREA was deleted. In lipid medium, the expression of genes involved in long-chain fatty acid degradation, ß-oxidation, the glyoxylate cycle, and utilization of arabinose, ethanol, or glycerol decreased in the Δsmek1 mutant, which is consistent with Δcrf1 in which a transcription activator CRF1 required for carbon metabolism was deleted. Lipase activity, however, increased in the Δsmek1 mutant in both glucose and lipid media. Moreover, Smek1 directly interacted with CreA and Crf1, and dephosphorylated CreA and Crf1 in vivo. The phosphatase Smek1 is therefore a dual-function regulator of the lipid and carbohydrate metabolism, and controls fungal development and virulence by coordinating the functions of CreA and Crf1 in carbon catabolite repression (CCR) and derepression (CCDR).

Color-encoded Escherichia coli assay via enzyme-induced etching of Au@MnO2 nanoparticles.

Au@MnO2 nanoparticles (NPs), as core-shell nanostructures, have been widely used in ions, molecules and enzyme activities detection due to their stable properties and easy preparation, but their application in bacterial pathogens detection is rarely reported. In this work, Au@MnO2 NPs is employed for Escherichia coli (E. coli) detection through monitoring and measuring ß-galactosidase (ß-gal) activity based enzyme-induced color-code single particle enumeration (SPE) method. In the existence of E. coli, p-aminophenylß-D-galactopyranoside (PAPG) can be hydrolyzed to generate p-aminophenol (AP) by the endogenous ß-gal of E. coli. MnO2 shell reacts with AP and produces Mn2+, causing the blue shift of the localized surface plasmon resonance (LSPR) peak and color change of the probe from bright yellow to green. With the SPE method, the amount of E. coli can be quantified readily. The detection limit reaches 15 CFU/mL with dynamic range from 100 to 2900 CFU/mL. Besides, this assay is effectively employed to monitor E. coli in river water sample. The designed sensing strategy provides an ultrasensitive and low cost way for E. coli detection and has the possibility to detect other bacteria in environmental monitoring and food quality analysis.

Evaluation of efficacy and safety for compound kushen injection combined with intraperitoneal chemotherapy for patients with malignant ascites: A systematic review and meta-analysis.

Objectives: Compound Kushen injection (CKI) combined with intraperitoneal chemotherapy (IPC) is widely used in the treatment of malignant ascites (MA). However, evidence about its efficacy and safety remains limited. This review aimed to evaluate the efficacy and safety of CKI combined with IPC for the treatment of MA. Methods: Protocol of this review was registered in PROSPERO (CRD42022304259). Randomized controlled trials (RCTs) on the efficacy and safety of IPC with CKI for the treatment of patients with MA were searched through 12 electronic databases and 2 clinical trials registration platforms from inception until 20 January 2023. The Cochrane risk-of-bias tool was used to assess the quality of the included trials through the risk of bias assessment. We included RCTs that compared IPC single used or CKI combined with IPC for patients with MA schedule to start IPC. The primary outcome was identified as an objective response rate (ORR), while the secondary outcomes were identified as the quality of life (QoL), survival time, immune functions, and adverse drug reactions (ADRs). The Revman5.4 and Stata17 software were used to calculate the risk ratio (RR) at 95% confidence intervals (CI) for binary outcomes and the mean difference (MD) at 95% CI for continuous outcomes. The certainty of the evidence was assessed according to the GRADE criteria. Results: A total of 17 RCTs were assessed, which included 1200 patients. The risk of bias assessment of the Cochrane risk-of-bias tool revealed that one study was rated high risk and the remaining as unclear or low risk. Meta-analysis revealed that CKI combined with IPC had an advantage in increasing ORR (RR = 1.31, 95% CI 1.20 to 1.43, p < 0.00001) and QoL (RR = 1.50, 95% CI 1.23 to 1.83, p < 0.0001) when compared with IPC alone. Moreover, the combined treatment group showed a lower incidence of myelosuppression (RR = 0.51, 95%CI 0.40-0.64, p < 0.00001), liver dysfunction (RR = 0.33, 95%CI 0.16 to 0.70, p = 0.004), renal dysfunction (RR = 0.39, 95%CI 0.17 to 0.89, p = 0.02), and fever (RR = 0.51, 95%CI 0.35 to 0.75, p = 0.0007) compared to those of the control group. The quality of evidence assessment through GRADE criteria showed that ORR, myelosuppression, and fever were rated moderate, renal dysfunction and liver dysfunction were rated low, and QoL and abdominal pain were rated very low. Conclusion: The efficacy and safety of CKI combined with IPC were superior to that with IPC alone for the treatment of MA, which indicates the potentiality of the treatment. However, more high-quality RCTs are required to validate this conclusion. Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022304259], identifier [PROSPERO 2022 CRD42022304259].

Cloning and functional analysis of the molting gene CYP302A1 of Daphnia sinensis.

BACKGROUND: Molting is an important physiological process in the growth and development of arthropoda, which is mainly regulated by juvenile hormone and ecdysone. CYP302A1 is a key enzyme which plays a critical role in the synthesis of ecdysone in insects, but it has not been identified in cladocera. RESULTS: The CYP302Al gene of Daphnia sinensis was cloned and its function was analyzed in this paper. The CYP302Al gene of D. sinensis was 5926 bp in full-length, with an open reading frame (ORF) of 1596 bp that encoded 531 amino acids (aa), a molecular weight of 60.82 kDa and an isoelectric point of 9.29. The amino acid sequence analysis revealed that there were five characteristic conserved regions of cytochrome P450 family (namely helix-C, helix-K, helix-I, PERF and heme-binding). In dsRNA mediated experiment, the expression level of CYP302A1 gene decreased significantly (knock-down of 56.22%) in the 5% Escherichia coli concentration treatment. In addition, the expression levels of EcR and USP and HR3 genes in the downstream were also significantly decreased, whereas that of FTZ-f1 gene increased significantly. In the 5% E. coli treatment, the molting time at maturity of D. sinensis prolonged, and the development of embryos in the incubation capsule appeared abnormal or disintegrated. The whole-mount in situ hybridization showed that the CYP302A1 gene of D. sinensis had six expression sites before RNA interference (RNAi), which located in the first antennal ganglion, ovary, cecae, olfactory hair, thoracic limb and tail spine. However, the expression signal of the CYP302A1 gene of D. sinensis disappeared in the first antennal ganglion and obviously attenuated in the ovary after RNAi. CONCLUSION: The CYP302A1 gene played an important role in the ecdysone synthesis pathway of D. sinensis, and the knock-down of the gene affected the molting and reproduction of D. sinensis.

PDGF-BB prevents destructive repair and promotes reparative osteogenesis of steroid-associated osteonecrosis of the femoral head in rabbits.

Destructive repair characterized by inadequate angiogenesis and osteogenesis is the main pathological progression in steroid-associated osteonecrosis of the femoral head (SONFH). Platelet-derived growth factor-BB (PDGF-BB) is an "angiogenesis and osteogenesis coupling" factor that has been used for the treatment of bone defects in clinic. This study was designed to analyze the ability of PDGF-BB for preventing destructive repair and promoting reparative osteogenesis in SONFH. Steroid-associated osteonecrosis (SAON) was induced and triggered destructive repair of the femoral head by repeated lipopolysaccharide (LPS) and methylprednisolone (MPS) injections in rabbits. At 2, 4, and 6 weeks after induction, recombinant human PDGF-BB, neutralizing PDGF-BB antibody, or saline was intramedullary injected into the proximal femora. At week 6 after SAON induction, the proximal femora were dissected for bone architecture and histological analysis. C3H10T1/2 cells and HUVECs were used for further mechanistic investigation. After PDGF-BB treatment, type H vessels and leptin receptor-positive (LepR+) mesenchymal stem cells (MSCs) increased in the affected femoral head, and more osteoblastic osteogenesis along the bone surfaces but scattered adipocytes in bone marrow tissue than that in the SAON group. PDGF-BB treatment prevented destructive repair progression and led to 50-70 % of osteonecrotic femoral heads undergoing reparative osteogenesis. In particular, we found that PDGF-BB could mediate MSC self-renewal and maintain their osteogenic potency by activating PDGFR/Akt/GSK3ß/CERB signaling in the presence of steroids. Moreover, PDGF-BB also stabled the newly formed vascular tubes by recruiting MSCs for improving intraosseous vascular integration. PDGF-BB may be a candidate for the promotion of reparative osteogenesis in SONFH.

Determination of ß-glucosidase activity using single-particle enumeration with Au@CeO2 nanoparticles.

A visible and sensitive assay for the quantitative detection of ß-glucosidase (ß-glu) activity based on Au@CeO2 core-shell nanoparticles (Au@CeO2 NPs) is described. As a hydrolytic enzyme, ß-glu can promote the hydrolysis of ß-arbutin to hydroquinone (HQ), which can trigger the decomposition of the CeO2 shell. With the single-particle enumeration (SPE) strategy coupled with dark field optical microscopy (DFM), an obvious color alteration of single Au@CeO2 NPs during the etching process can be observed in real-time. By statistically calculating the number of the etched nanoparticles, the ß-glu activity level can be quantified accurately. This assay displays a broad linear range from 0.5 to 50 mU⋅mL-1 and low detection limit of 0.12 mU⋅mL-1. In addition, this method was successfully used to determine ß-glu in real samples and acquires satisfactory recoveries in the range of 97.1-102.0%. This study provides a visualization analysis method for ß-glu, which may be helpful for monitoring other targets in the future.

Genome-Wide Prediction and Analysis of Oryza Species NRP Genes in Rice Blast Resistance.

Members of the N-rich proteins (NRPs) gene family play important roles in the plant endoplasmic reticulum stress in response, which can be triggered by plant pathogens' infection. Previous studies of the NRP gene family have been limited to only a few plants, such as soybean and Arabidopsis thaliana. Thus, their evolutionary characteristics in the Oryza species and biological functions in rice defense against the pathogenic fungus Magnaporthe oryzae have remained unexplored. In the present study, we demonstrated that the NRP genes family may have originated in the early stages of plant evolution, and that they have been strongly conserved during the evolution of the Oryza species. Domain organization of NRPs was found to be highly conserved within but not between subgroups. OsNRP1, an NRP gene in the Oryza sativa japonica group, was specifically up-regulated during the early stages of rice-M. oryzae interactions-inhibited M. oryzae infection. Predicted protein-protein interaction networks and transcription-factor binding sites revealed a candidate interactor, bZIP50, which may be involved in OsNRP1-mediated rice resistance against M. oryzae infection. Taken together, our results established a basis for future studies of the NRP gene family and provided molecular insights into rice immune responses to M. oryzae.

Mesenchymal stem cells exosomal let-7a-5p improve autophagic flux and alleviate liver injury in acute-on-chronic liver failure by promoting nuclear expression of TFEB.

Acute-on-chronic liver failure is a distinct clinical syndrome characterized by a dysregulated immune response and extensive hepatocyte death without satisfactory therapies. As a cytoplasmic degradative and quality-control process, autophagy was implicated in maintaining intracellular homeostasis, and decreased hepatic autophagy was found in many liver diseases and contributes to disease pathogenesis. Previously, we identified the therapeutic potential of mesenchymal stem cells (MSCs) in ACLF patients; however, the intrinsic mechanisms are incompletely understood. Herein, we showed that MSCs restored the impaired autophagic flux and alleviated liver injuries in ACLF mice, but these effects were abolished when autophago-lysosomal maturation was inhibited by leupeptin (leu), suggesting that MSCs exerted their hepatoprotective function in a pro-autophagic dependent manner. Moreover, we described a connection between transcription factor EB (TFEB) and autophagic activity in this context, as evidenced by increased nuclei translocation of TFEB elicited by MSCs were capable of promoting liver autophagy. Mechanistically, we confirmed that let-7a-5p enriched in MSCs derived exosomes (MSC-Exo) could activate autophagy by targeting MAP4K3 to reduce TFEB phosphorylation, and MAP4K3 knockdown partially attenuates the effect of anti-let-7a-5p oligonucleotide via decreasing the inflammatory response, in addition, inducing autophagy. Altogether, these findings revealed that the hepatoprotective effect of MSCs may partially profit from its exosomal let-7a-5p mediating autophagy repairment, which may provide new insights for the therapeutic target of ACLF treatment.