Detection Transformer with Multi-Scale Fusion Attention Mechanism for Aero-Engine Turbine Blade Cast Defect Detection Considering Comprehensive Features.

Casting defects in turbine blades can significantly reduce an aero-engine's service life and cause secondary damage to the blades when exposed to harsh environments. Therefore, casting defect detection plays a crucial role in enhancing aircraft performance. Existing defect detection methods face challenges in effectively detecting multi-scale defects and handling imbalanced datasets, leading to unsatisfactory defect detection results. In this work, a novel blade defect detection method is proposed. This method is based on a detection transformer with a multi-scale fusion attention mechanism, considering comprehensive features. Firstly, a novel joint data augmentation (JDA) method is constructed to alleviate the imbalanced dataset issue by effectively increasing the number of sample data. Then, an attention-based channel-adaptive weighting (ACAW) feature enhancement module is established to fully apply complementary information among different feature channels, and further refine feature representations. Consequently, a multi-scale feature fusion (MFF) module is proposed to integrate high-dimensional semantic information and low-level representation features, enhancing multi-scale defect detection precision. Moreover, R-Focal loss is developed in an MFF attention-based DEtection TRansformer (DETR) to further solve the issue of imbalanced datasets and accelerate model convergence using the random hyper-parameters search strategy. An aero-engine turbine blade defect X-ray (ATBDX) image dataset is applied to validate the proposed method. The comparative results demonstrate that this proposed method can effectively integrate multi-scale image features and enhance multi-scale defect detection precision.

Enabling Modular Click Chemistry Library through Sequential Ligations of Carboxylic Acids and Amines.

High-throughput synthesis and screening of chemical libraries play pivotal roles in drug discovery. Click chemistry has emerged as a powerful strategy for constructing highly modular chemical libraries. However, the development of new click reactions and unlocking new click able building blocks remain exceedingly challenging. Here in , we describe a double-click strategy that enables the sequential ligation of widely available carboxylic acids and amines with fluorosulfuryl isocyanate (FSO 2 NCO) via a modular amidation/SuFEx process. This method provides facile access to chemical libraries of N-fluorosulfonyl amides (RCONHSO 2 F) and N-acylsulfamides (RCONHSO 2 NR ´ R ´´ ) in near-quantitative yields under simple and practical conditions. The robustness and efficiency of this double click strategy is showcased by the facile construction of chemical libraries in 96-well microtiter plates from a large number of carboxylic acids and amines. Preliminary biological activity screening reveals that some compound s  exhibit high antimicrobial activities against Gram-positive bacterium  S. aureus and drug-resistant MRSA (MIC up to 6.25·µg mL-1). These results provide compelling evidence for the potential application of modular click chemistry library as an enabling technology in high-throughput medicinal chemistry.

Hsa_circ_0003945 promotes progression of hepatocellular carcinoma by mediating miR-34c-5p/LGR4/ß-catenin axis activity.

Accumulating evidence suggests that circular RNAs (circRNAs) play essential roles in regulating cancer progression, but many circRNAs in hepatocellular carcinoma (HCC) remain unknown. Dysregulated circRNAs in HCC were identified through bioinformatics analysis of Gene Expression Omnibus data sets. Quantitative real-time PCR (qRT-PCR), Sanger sequencing, RNase R digestion and actinomycin D treatment were conducted to confirm the characterization of circRNAs. CCK-8, wound-healing and Transwell assays were performed to assess the functional roles of Hsa_circ_0003945 (Circ_0003945) in HCC cell lines. Subcellular fractionation and fluorescence in situ hybridization (FISH) were performed to locate Circ_0003945 in HCC cells. Dual-luciferase reporter assay was executed to verify the binding of Circ_0003945 to microRNAs (miRNAs) or the miRNAs to their target genes. In this study, we found that Circ_0003945 was upregulated in HCC tissue, and higher Circ_0003945 expression was positively correlated with tumour size and tumour stage. Furthermore, high plasma levels of circulating Circ_0003945 were confirmed in HCC patients compared with those in non-HCC groups. The functional experiments revealed that overexpression or knockdown of Circ_0003945 promoted or attenuated tumour growth and migration, respectively. Mechanistically, Circ_0003945 might exert as a miR-34c-5p sponge to upregulate the expression of leucine-rich repeat-containing G protein-coupled receptor 4 (LGR4), activating the ß-catenin pathway, and finally facilitating HCC progression. Additionally, a ß-catenin activator could reverse the effect of Circ_0003945 knockdown. In conclusion, Circ_0003945 exerts a tumour-promoting role in HCC cells by regulating the miR-34c-5p/LGR4/ß-catenin axis, which may be a potential target for HCC therapy.

Nanozyme based on ZIF-8 for the colorimetric detection of sulfonamides in cow milk.

A simple and time-saving colorimetric method was developed to quantify sulfonamides (SAAs) in milk via inhibition of the human carbonic anhydrase II (hCAII)-like activity of ZIF-8 that can hydrolyze p-nitrophenyl acetate (pNPA) to p-nitrophenol (pNP), following the color change from yellow to colorless. Effects of different reaction conditions, including pH, temperature, amount of ZIF-8, and incubation time, were investigated. The value of Michaelis-Menten constant (Km) is measured to be 0.15 mM, which exhibits high affinity to pNPA. The IC50 (0.17, 0.24, and 0.60 mM) and inhibition constant (Ki) (0.09, 0.13, and 0.33 mM) of sulfamethazine (SD), sulfadimethoxine (SDM), and sulfathiazole (ST) on ZIF-8 were measured, respectively. Moreover, the activity of ZIF-8 remains more than 90.0% of its initial activity after 30 days' storage. The colorimetric method for SD, SDM, and ST determination was established at the linear ranges of 6.3-750.0 µM (1.75-208.75 mg/kg), 6.3-750.0 µM (1.96-232.75 mg/kg), and 5.0-1250.0 µM (1.28-319.15 mg/kg) with limit of detection of 4.3, 3.2, and 3.9 µΜ (1.2, 0.99, and 0.96 mg/kg), respectively. In addition, the spiked recoveries of SAAs in milk sample are in the range of 81.6%-106.7% with RSD less than 6.5%. In short, the developed colorimetric method can achieve rapid analysis of SAAs in milk with simple operations.

LncRNA CRNDE promotes cell proliferation, migration and invasion of ovarian cancer via miR-423-5p/FSCN1 axis.

Ovarian cancer seriously threatens the health of women. LncRNA CRNDE is known to be upregulated in ovarian cancer. However, the mechanism by which CRNDE regulates the progress of ovarian cancer is largely unknown. MTT assay was applied to measure the cell viability. Colony formation assay was used to measure the cell proliferation. Cell migration was tested by wound healing, and Transwell assay was performed to detect cell invasion. In addition, the expression of miR-423-5p, CRNDE and FSCN1 were detected by RT-qPCR and western blotting, respectively. Meanwhile, dual-luciferase reporter assay and RIP assay were performed to explore the correlation between miR-423-5p and CRNDE (or FSCN1). CRNDE and FSCN1 were upregulated in ovarian cancer cells (SKOV3, CAOV-3, IGROV1, A2780 and C13K), while miR-423-5p was downregulated. Moreover, silencing of FSCN1/CRNDE significantly decreased proliferation, migration and invasion of ovarian cancer cells (SKOV3 and CI3K) via suppressing MMP-2 and MMP-9. In addition, CRNDE could sponge miR-423-5p, and FSCN1 was confirmed to be the direct target of miR-423-5p. Furthermore, CRNDE knockdown-induced inhibition of FSCN1 was notably reversed by miR-423-5p downregulation. Knockdown of CRNDE inhibited cell proliferation, migration and invasion of ovarian cancer via miR-423-5p/FSCN1 axis. Thus, CRNDE may serve a new target for ovarian cancer.

Silver-mediated radical oxytrifluoromethylation of unsaturated carboxylic acids for the synthesis of γ-trifluoromethylthio lactones.

An efficient silver-mediated oxidative trifluoromethylthiolation of unsaturated carboxylic acids to construct trifluoromethylthiol-containing lactones has been disclosed. In this protocol no metal-catalysts was added, and preliminary mechanism investigations suggested that a free-radical pathway should be involved in the process. High functional group tolerance and excellent yields were demonstrated by the efficient preparation of a wide range of γ-trifluoromethylthiolated phthalides.

Exosomal microRNAs in the DLK1-DIO3 imprinted region derived from cancer-associated fibroblasts promote progression of hepatocellular carcinoma by targeting hedgehog interacting protein.

BACKGROUND: Hepatocellular carcinoma (HCC) is the sixth most commonly diagnosed cancer and third leading cause of cancer-related death worldwide in 2020. Exosomes derived from cancer-associated fibroblasts (CAFs-exo) can promote tumor progression in various human cancers. However, the underlying regulatory mechanism controlling how CAFs-exo can promote HCC progression remains poorly understood. METHODS: CAFs and para-cancer fibroblasts (PAFs) were isolated from HCC tissues and corresponding para-cancer tissues, then were cultured in vitro. CAFs and PAFs were characterized by immunofluorescence and western blot (WB) assays. Exosomes were isolated by ultracentrifugation, and characterized by transmission electron microscopy, nanoflow cytometry, and WB assay. The internalization of exosomes by HCC cells was observed under a fluorescence microscope. Cell Counting Kit-8 (CCK-8) assay was used to evaluate cell proliferation. Wound healing and transwell assays were used for migration and invasion experiments. RT-PCR assay was used to examine differentially expressed microRNAs (miRNAs) in exosomes and HCC cells. The TargetScan database was used to predict miRNA target genes. Hedgehog interacting protein (HHIP) expression analysis, prognostic analysis, and enrichment analysis of HHIP-related co-expressed genes were performed using the TIMER, UALCAN, Kaplan-Meier plotter, and LinkedOmics databases. RESULTS: CAFs-exo were internalized by HCC cells. CAFs-exo contributed to the aggressive phenotype of HCC cells, while inhibiting exosome secretion reversed these effects. Mechanistically, miRNAs in the DLK1-DIO3 imprinted region (miR-329-3p, miR-380-3p, miR-410-5p, miR-431-5p) were increased in HCC cells co-cultured with CAFs-exo compared with PAFs-exo. Expression of HHIP, a possible miR-431-5p target gene, was significantly downregulated in HCC cells. Low HHIP expression level in tumor tissues could predict poor prognosis in HCC patients. HHIP-related co-expressed genes were mainly associated with cell adhesion molecules. CONCLUSIONS: CAFs-exo can promote HCC progression by delivering miRNAs in the DLK1-DIO3 imprinted region to HCC cells, subsequently inhibiting HHIP expression. HHIP is a potential prognostic biomarker in HCC.

Modern thromboprophylaxis protocol based on guidelines applied in a respiratory intensive care unit: a single-center prospective cohort study.

BACKGROUND: Critically ill patients in intensive care units (ICUs) are at high risk of venous thromboembolism (VTE). This study aimed to explore the prophylaxis effect under a guideline-based thromboprophylaxis protocol among critically ill patients in a respiratory ICU. METHODS: For this single-center prospective cohort study, we followed the thromboprophylaxis protocol, which was drawn up based on relevant guidelines and Chinese experts' advice. Clinical data were entered into an electronic case report form and analyzed. Multivariate logistic regression was conducted to explore independent risk factors of VTE event under this protocol. RESULTS: From August 1, 2014, to December 31, 2020, 884 patients underwent thromboprophylaxis according to this protocol; 10.5% of them received mechanical prophylaxis, 43.8% received pharmacological prophylaxis, and 45.7% received pharmacological combined with mechanical prophylaxis. The proportion of VTE events was 14.3% for patients who received the thromboprophylaxis protocol, of which 0.1% had pulmonary thromboembolism (PTE), 2.0% had proximal deep vein thrombosis (DVT), and 12.1% had isolated distal DVT. There was no significant difference between different thromboprophylaxis measures. Cirrhosis (OR 5.789, 95% CI [1.402, 23.894], P = 0.015), acute asthma exacerbation (OR 39.999, 95% CI [4.704, 340.083], P = 0.001), and extracorporeal membrane oxygenation treatment (OR 22.237, 95%CI [4.824, 102.502], P < 0.001) were independent risk factors for proximal DVT under thromboprophylaxis. CONCLUSIONS: The thromboprophylaxis protocol based on guidelines applied in the ICU was practicable and could help decrease the proportion of PTE and proximal DVT events. The risk factors of VTE events happening under the thromboprophylaxis protocol require more attention. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02213978.

Urotensin II activates the ferroptosis pathway through circ0004372/miR-124/SERTAD4 to promote the activation of vascular adventitial fibroblasts.

Both vascular adventitial fibroblasts (VAFs) and urotensin II (UII) play important roles in vascular remodeling diseases, but the mechanism of UII in VAFs is still unclear. UII inhibited miR-124 expression through up-regulating circ0004372 expression, thereby promoting SERTAD4 expression. UII significantly promoted the generation of ROS, MDA and 4-HNE, reduced the activities of SOD, GST and GR, increased Fe2+ concentration and inhibited GPX4 expression through circ0004372/miR-124/SERTAD4. Both UII and ferroptosis inducer Erastin significantly promoted the expression of α-SMA, Collagen I and TGF-ß1 in VAFs, but circ0004372 siRNA, miR-124 mimics, SERTAD4 siRNA or Ferrostatin-1 significantly inhibited the effect of UII and Erastin on cell activation. When co-transfected with circ0004372 siRNA and miR-124 inhibitors or miR-124 mimics and SERTAD4 overexpression vector, UII still significantly increased the expression of α-SMA, Collagen I and TGF-ß1. After transfection with circ0004372 overexpression vector, miR-124 inhibitors or SERTAD4 overexpression vector and then treating with UII and Ferrostatin-1, the expression of α-SMA, Collagen I and TGF-ß1 was still significant; when the circ0004372 overexpression vector and miR-124 mimics or miR-124 inhibitors and SERTAD4 siRNA were co-transfected and then UII and Ferrostatin-1 were added, the expression of α-SMA, Collagen I and TGF-ß1 was not significantly increased. Therefore, these results indicate that UII promotes the activation of VAFs through the circ0004372/miR-124/SERTAD4/ferroptosis pathway.

Zeolitic imidazolate frameworks as light-responsive oxidase-like mimics for the determination of adenosine triphosphate and discrimination of phenolic pollutants.

In this study, 3,3',5,5'-tetramethylbenzidine (TMB) was selected as a chromogenic substrate to evaluate the light-responsive oxidase-like activity of different zeolitic imidazolate frameworks (ZIFs). The synthesized ZIFs were systematically characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction analysis. Several main operational parameters, including ZIFs and TMB concentrations, pH value, radiation time, and working current, in the reaction process were optimized. The kinetic measurement results show that ZIF-90 exhibits higher affinity to the substrate than horseradish peroxidase. Furthermore, given that adenosine triphosphate (ATP) can specifically combine with Zn2+ binding site and destroy the structure of ZIF-90, a specific and sensitive colorimetric method was established for the quantitative detection of ATP within the range 10 - 240 µM. In addition, on the basis that phenolic pollutants can impact the reaction kinetics diversely on different ZIFs, a sensor array was constructed and successfully applied to differentiate five phenolic pollutants in lake water samples. This work is expected to shed light on the establishment of ZIF-based light-responsive oxidase-like nanozymes for the highly selective colorimetric detection and sensor array.

Investigation on the Peroxidase-like Activity of Vitamin B6 and Its Applications in Colorimetric Detection of Hydrogen Peroxide and Total Antioxidant Capacity Evaluation.

The peroxidase-like activity of vitamin B6 (VB6) was firstly demonstrated by catalyzing the peroxidase chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) at the existence of H2O2. The influence of different factors on the catalytic property of VB6, including pH, temperature, VB6 concentration, and incubation time, were investigated. The steady-state kinetic study results indicate that VB6 possesses higher affinity to H2O2 than natural horseradish peroxidase and some other peroxidase mimics. Besides, the radical quenching experiment results confirm that hydroxyl radical (•OH) accounts for the catalytic process. Based on the excellent peroxidase-like catalytic activity of VB6, the colorimetric methods for H2O2 and gallic acid (GA) detection were developed by measuring the absorbance variance of the catalytic system. Under the optimal conditions, the linear ranges of the methods for H2O2 and GA determination with good selectivity are 50.0-600.0 µM and 10.0-50.0 µM, respectively. In addition, the developed method was applied in the detection of H2O2 in milk samples and evaluation of total antioxidant capacity of different tea infusions. This study may broaden the application prospect of VB6 in environmental and biomedical analysis fields, contribute to profound insight of the physiological functions of VB6, as well as lay foundation for further excavation of small-molecule peroxidase mimics.

[To explore mechanism of Scabiosa comosa against liver fibrosis based on pharmacodynamics and network pharmacology].

This study aims to systematically elucidate the pharmacodynamics and network pharmacological mechanism of Mongolian medicinal plants Scabiosa comosa, explore their key targets and related pathways, and further clarify the mechanism of the plants in treating liver fibrosis. Wistar rats were assigned into the blank group, carbon tetrachloride-induced liver fibrosis model group, and low-, medium-, and high-dose S. comosa groups. HE staining and Masson staining were performed for the observation of liver tissue under a microscope. Further, Wistar rats were assigned into a control group and a S. comosa group for administration. Seven days later, blood was collected from the abdominal aorta, and different doses of drug-containing serum samples were used to treat hepatic stellate cell-T6(HSC-T6). Flow cytometry was adopted to detect the apoptosis of HSC-T6 cells. Ultra-high performance liquid chromatography-time of flight-mass spectrometry(UHPLC-TOF-MS) was employed to determine the components in Scabiosa comosa. The target of S. comosa and liver fibrosis were obtained from SwissTargetPrediction and GeneCards, respectively, and the common targets were selected as the anti-liver fibrosis targets. Protein-protein interaction was analyzed via STRING. Gene Ontology(GO) annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment were carried out via Metascape. Phosphatidylinosital 3-kinase(PI3 K), protein kinase B(AKT), p-AKT, p38, and p-p38 targets which are involved in the top-ranked PI3 K/AKT and mitogen activated kinase-like protein(MAPK) signaling pathways were selected for validation via Western blot. The HE and Masson staining results showed that Scabiosa alleviated the hyperplasia of connective tissue and the fibrosis. The serum containing Scabiosa significantly promoted the apoptosis of HSC-T6 in a concentration-dependent manner. A total of 76 chemical components were identified by UHPLC-TOF-MS, among which flavonoids, alkaloids, terpenoids, phenols, and fatty acids were the main components. According to the prediction, there were 63 anti-liver fibrosis targets in Scabiosa comosa, the annotated GO terms of which involved biological processes, cell components, and molecular functions. The KEGG pathway enrichment showed that the targets were mainly involved in PI3 K/AKT, epidermal growth factor receptor(EGFR), RAS-associated protein 1(Rap1), hypoxia-inducible factor 1(HIF-1), resistance to audiogenic seizures(Ras), and MAPK signaling pathways. Western blot results showed that compared with the model group, S. comosa down-regulated the protein levels of α-smooth muscle actin(α-SMA), collagen Ⅰ, PI3 K, AKT, p-AKT, p38, and p-p38 in liver tissue. Compared with the control group, the low-, medium-, and high-dose S. comosa significantly down-regulated the protein levels of α-SMA, collagen Ⅰ, PI3 K, AKT, p-AKT, p38, and p-p38 in HSC-T6. The evidence of pharmacodynamics, network pharmacology, and molecular biology indicated that the plants of S. comosa had significant activity against liver fibrosis, the mechanism of which may involve the regulation of the key targets PI3 K, AKT, and MAPK14 p38 in the PI3 K/AKT and MAPK signaling pathways.

Effects of ER-resident and secreted AGR2 on cell proliferation, migration, invasion, and survival in PANC-1 pancreatic cancer cells.

BACKGROUND: Anterior gradient-2 (AGR2) is a proto-oncogene involved in tumorigenesis and cancer progression. AGR2, predominantly localized in the endoplasmic reticulum (ER), is also a secreted protein detected in the extracellular compartment in multiple cancers. However, the biological functions of intracellular and extracellular AGR2 remain to be elucidated. METHODS: Based on the biochemical structure of AGR2 protein, PANC-1 pancreatic cancer cells stably expressing ER-resident or secreted AGR2 were generated by a lentivirus-mediated stable overexpression system. The capacities of cell proliferation, migration, invasion and survival were assessed in PANC-1 stable cells. Moreover, EGFR expression and activation were determined to explore the possible mechanism of AGR2 roles in pancreatic cancer tumorigenesis. RESULTS: It was discovered that secreted AGR2, but not ER-resident AGR2, promotes cell proliferation, migration and invasion of PANC-1 cells. Moreover, the data indicated that both the ER-resident and the secreted AGR2 enhance the survival capacity of PANC-1 cells after tunicamycin-induced ER stress and gemcitabine treatment. However, EGFR expression and activation were not found to be involved in AGR2-dependent oncogenic phenotypes in PANC-1 cells. CONCLUSIONS: Secreted AGR2 is predominantly involved in cell proliferation, migration and invasion in PANC-1 pancreatic cancer cells. Both secreted and ER-resident AGR2 contribute to the survival of PANC-1 cells under the challenging conditions. These findings provide insight into how different localizations of AGR2 have contributed to pancreatic cancer growth, metastasis, and drug sensitivity.

Comprehensive analysis of the cancer driver genes in breast cancer demonstrates their roles in cancer prognosis and tumor microenvironment.

BACKGROUND: Breast cancer is the most common malignancy in women. Cancer driver gene-mediated alterations in the tumor microenvironment are critical factors affecting the biological behavior of breast cancer. The purpose of this study was to identify the expression characteristics and prognostic value of cancer driver genes in breast cancer. METHODS: The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets are used as the training and test sets. Classified according to cancer and paracancerous tissues, we identified differentially expressed cancer driver genes. We further screened prognosis-associated genes, and candidate genes were submitted for the construction of a risk signature. Functional enrichment analysis and transcriptional regulatory networks were performed to search for possible mechanisms by which cancer driver genes affect breast cancer prognosis. RESULTS: We identified more than 200 differentially expressed driver genes and 27 prognosis-related genes. High-risk group patients had a lower survival rate compared to the low-risk group (P<0.05), and risk signature showed high specificity and sensitivity in predicting the patient prognosis (AUC 0.790). Multivariate regression analysis suggested that risk scores can independently predict patient prognosis. Further, we found differences in PD-1 expression, immune score, and stromal score among different risk groups. CONCLUSION: Our study confirms the critical prognosis role of cancer driver genes in breast cancer. The cancer driver gene risk signature may provide a novel biomarker for clinical treatment strategy and survival prediction of breast cancer.

Phytochemistry and Pharmacological Activities of the Diterpenoids from the Genus Daphne.

There are abundant natural diterpenoids in the plants of the genus Daphne from the Thymelaeaceae family, featuring a 5/7/6-tricyclic ring system and usually with an orthoester group. So far, a total of 135 diterpenoids has been isolated from the species of the genus Daphne, which could be further classified into three main types according to the substitution pattern of ring A and oxygen-containing functions at ring B. A variety of studies have demonstrated that these compounds exert a wide range of bioactivities both in vitro and in vivo including anticancer, anti-inflammatory, anti-HIV, antifertility, neurotrophic, and cholesterol-lowering effects, which is reviewed herein. Meanwhile, the fascinating structure-activity relationship is also concluded in this review in the hope of providing an easy access to available information for the synthesis and optimization of efficient drugs.

Antagonizing miR-7 suppresses B cell hyperresponsiveness and inhibits lupus development.

OBJECTIVES: The objective of this study was to address the biological function of miR-7 in an animal model of systemic lupus erythematosus. METHODS: MRLlpr/lpr lupus mice were administrated antagomiR-7 or a scramble control by tail vein for 5weeks. Three groups of animals' tissues were assessed for lupus manifestations by immunofluorescence and immunohistochemistry, and serum was examined for levels of autoantibodies and inflammatory cytokines. Splenic B cell subsets were assessed for intracellular expression of PI3K signaling by FACS. Finally, the ability of the miR-7 antagomir to regulate the expansion of T follicular helper (Tfh) cells and B cell hyperresponsiveness was further explored. RESULTS: We found that miR-7 was up-regulated in MRLlpr/lpr lupus mice and directly targeted PTEN mRNA in B cells. Up-regulated miR-7 in MRLlpr/lpr lupus B cells was negatively correlated with PTEN expression. Notably, miR-7 antagomir treatment reduced lupus manifestations in MRLlpr/lpr lupus mice. miR-7-mediated down-regulation of PTEN/AKT signaling promoted B cell differentiation into plasmablasts/plasma cells and spontaneous germinal center (GC) formation, whereas miR-7 antagomir normalized splenic B cell subtypes. Besides suppressing the activation of B cells, miR-7 antagomir intervention also down-regulated STAT3 phosphorylation and production of IL-21 and reduced Tfh expansion. CONCLUSION: The above data have demonstrated the critical roles of miR-7 not only in regulating PTEN expression and also B cell and Tfh cell function in lupus-prone MRLlpr/lpr lupus mice. Furthermore, the disease manifestations in MRLlpr/lpr lupus mice are efficiently improved by miR-7 antagomir, indicating miR-7 as a potential treatment strategy in SLE.

Metagenomic profiling of the pro-inflammatory gut microbiota in ankylosing spondylitis.

OBJECTIVE: Gut dysbiosis has been reported implicated in ankylosing spondylitis (AS), a common chronic inflammatory disease mainly affects sacroiliac joints and spine. Utilizing deep sequencing on the feces of untreated AS patients, our study aimed at providing an in-depth understanding of AS gut microbiota. METHODS: We analyzed the fecal metagenome of 85 untreated AS patients and 62 healthy controls by metagenomic shotgun sequencing, and 23 post-treatment feces of those AS patients were collected for comparison. Comparative analyses among different cohorts including AS, rheumatoid arthritis and Behcet's disease were performed to uncover some common signatures related to inflammatory arthritis. Molecular mimicry of a microbial peptide was also demonstrated by ELISpot assay. RESULTS: We identified AS-enriched species including Bacteroides coprophilus, Parabacteroides distasonis, Eubacterium siraeum, Acidaminococcus fermentans and Prevotella copri. Pathway analysis revealed increased oxidative phosphorylation, lipopolysaccharide biosynthesis and glycosaminoglycan degradation in AS gut microbiota. Microbial signatures of AS gut selected by random forest model showed high distinguishing accuracy. Some common signatures related to autoimmunity, such as Bacteroides fragilis and type III secretion system (T3SS), were also found. Finally, in vitro experiments demonstrated an increased amount of IFN-γ producing cells triggered by a bacterial peptide of AS-enriched species, mimicking type II collagen. CONCLUSIONS: These findings collectively indicate that gut microbiota was perturbed in untreated AS patients with diagnostic potential, and some AS-enriched species might be triggers of autoimmunity by molecular mimicry. Additionally, different inflammatory arthritis shared some common microbial signatures.

Daphnane Diterpenoids from Daphne genkwa Inhibit PI3K/Akt/mTOR Signaling and Induce Cell Cycle Arrest and Apoptosis in Human Colon Cancer Cells.

Seven new daphnane-type diterpenoids, daphgenkins A-G (1-7), and 15 known analogues (8-22) were isolated from the flower buds of Daphne genkwa. Their structures and absolute configurations were elucidated by spectroscopic data and calculated ECD analyses. The cytotoxicities of all daphnane-type diterpenoids (1-22) obtained were evaluated against three human colon cancer cell lines (SW620, RKO, and LoVo). Compounds 1, 12, and 13 exhibited cytotoxic effects against the SW620 and RKO cell lines, with IC50 values in the range of 3.0-9.7 µM. The most active new compound, 1, with an IC50 value of 3.0 µM against SW620 cells, was evaluated further for its underlying molecular mechanism. Compound 1 induced G0/G1 cell cycle arrest, leading to the induction of apoptosis in SW620 cells. Also, it induced cancer cell apoptosis by an increased ratio of Bax/Bcl-2, activated cleaved caspase-3 and caspase-9, and upregulated PARP. Finally, compound 1 significantly inhibited PI3K/Akt/mTOR signaling in SW620 cells. Together, the results suggest that compound 1 may be a suitable lead compound for further biological evaluation.

Muramyl dipeptide promotes Aß1-42 oligomer production via the NOD2/p-p38 MAPK/BACE1 signaling pathway in the SH-SY5Y cells.

The relationship between chronic bacterial colonization in the brain and Alzheimer's disease is attracting extensive attention. Recent studies indicated that the components of bacterial biofilm drive the amyloid-ß production. Muramyl dipeptide, the minimal bioactive peptidoglycan motif common to all bacteria, contributes to the development of many central inflammatory and neurodegenerative disorders. However, the involvement of Muramyl dipeptide in amyloid-ß production is not completely defined. In our present study, wild type mice received an intracerebroventricular injection of normal saline or Muramyl dipeptide. Data showed that the production of Aß1-42 oligomers was significantly increased after Muramyl dipeptide injection in the wild type mice or incubation of the SH-SY5Y cells with Muramyl dipeptide. Moreover, the action of Muramyl dipeptide was dose- and time-dependent. The above results suggested a possibility that the Muramyl dipeptide-induced Aß1-42 oligomer production might be related to the NOD2/p-p38 MAPK/BACE1 pathway. To confirm this, the SH-SY5Y cells were transfected with siRNA NOD2. Data showed that the transfected SH-SY5Y cells exhibited decreased expression of Aß1-42 oligomer, NOD2, p-p38 MAPK, and BACE1 after treatment with Muramyl dipeptide. Finally, SH-SY5Y cells were pretreated with SB203580, an inhibitor of the p-38-MAPK pathway. The results indicated that these pretreated SH-SY5Y cells exhibited decreased expression of Aß1-42 oligomer, p-p38 MAPK, and BACE1 after treatment with Muramyl dipeptide. In conclusion, these results suggested that Muramyl dipeptide was the trigger factor for Aß1-42 oligomer production, which probably acts via the NOD2/p-p38 MAPK/BACE1 signaling pathway.

Tanshinone IIA attenuates high glucose induced human VSMC proliferation and migration through miR-21-5p-mediated tropomyosin 1 downregulation.

The proliferation and migration of vascular smooth muscle cells (VSMCs) play important roles in the development and progression of diabetes-related vascular complications. Recently, microRNAs (miRNAs) have been suggested to be involved in the pathogenesis of vascular diseases. This study was designed to investigate the influences of tanshinone IIA, an active compound extracted from Chinese herb Salvia miltiorrhiza, on the proliferation and migration of human aortic VSMCs (HASMCs). cultured in a high glucose medium and the underlying mechanisms related miRNAs. Using a miRNA microarray method, we profiled the miRNA expression signature in human aortic VSMCs (HASMCs) exposed to normal glucose, high glucose with and without Tanshinone IIA. Cell proliferation was measured with 5-bromo-2'-deoxyuridine (BrdU) incorporation assay. Cell migration was evaluated using transwell migration assay and wound scratch assay. Western blot was used to examine the expression of tropomyosin 1 (TPM1) and miRNA level was quantified by real-time PCR. The results showed that several miRNAs that were highly expressed in the high glucose group were significantly decreased in the high glucose with Tanshinone IIA group compared with the normal glucose group (P < 0.05). Among these miRNAs, miR-21-5p was significantly upregulated in the high glucose group and downregulated after Tanshinone IIA treatment (P < 0.05). The depletion of miR-21-5p in HASMCs resulted in decreased cell proliferation and migration (P < 0.05). Moreover, we found that Tanshinone IIA inhibited proliferation and migration partly through miR-21-5p-mediated TPM1 downregulation (P < 0.05). In conclusion, the present study demonstrates that Tanshinone IIA is able to protect HASMCs from high glucose-induced proliferation and migration through regulating expression of miRNAs.