Identification of QTNs, QTN-by-environment interactions, and their candidate genes for salt tolerance related traits in soybean.

BACKGROUND: Salt stress significantly reduces soybean yield. To improve salt tolerance in soybean, it is important to mine the genes associated with salt tolerance traits. RESULTS: Salt tolerance traits of 286 soybean accessions were measured four times between 2009 and 2015. The results were associated with 740,754 single nucleotide polymorphisms (SNPs) to identify quantitative trait nucleotides (QTNs) and QTN-by-environment interactions (QEIs) using three-variance-component multi-locus random-SNP-effect mixed linear model (3VmrMLM). As a result, eight salt tolerance genes (GmCHX1, GsPRX9, Gm5PTase8, GmWRKY, GmCHX20a, GmNHX1, GmSK1, and GmLEA2-1) near 179 significant and 79 suggested QTNs and two salt tolerance genes (GmWRKY49 and GmSK1) near 45 significant and 14 suggested QEIs were associated with salt tolerance index traits in previous studies. Six candidate genes and three gene-by-environment interactions (GEIs) were predicted to be associated with these index traits. Analysis of four salt tolerance related traits under control and salt treatments revealed six genes associated with salt tolerance (GmHDA13, GmPHO1, GmERF5, GmNAC06, GmbZIP132, and GmHsp90s) around 166 QEIs were verified in previous studies. Five candidate GEIs were confirmed to be associated with salt stress by at least one haplotype analysis. The elite molecular modules of seven candidate genes with selection signs were extracted from wild soybean, and these genes could be applied to soybean molecular breeding. Two of these genes, Glyma06g04840 and Glyma07g18150, were confirmed by qRT-PCR and are expected to be key players in responding to salt stress. CONCLUSIONS: Around the QTNs and QEIs identified in this study, 16 known genes, 6 candidate genes, and 8 candidate GEIs were found to be associated with soybean salt tolerance, of which Glyma07g18150 was further confirmed by qRT-PCR.

A WRI1-dependent module is essential for the accumulation of auxin and lipid in somatic embryogenesis of Arabidopsis thaliana.

The potential for totipotency exists in all plant cells; however, the underlying mechanisms remain largely unknown. Earlier findings have revealed that the overexpression of LEAFY COTYLEDON 2 (LEC2) can directly trigger the formation of somatic embryos on the cotyledons of Arabidopsis. Furthermore, cotyledon cells that overexpress LEC2 accumulate significant lipid reserves typically found in seeds. The precise mechanisms and functions governing lipid accumulation in this process remain unexplored. In this study, we demonstrate that WRINKLED1 (WRI1), the key regulator of lipid biosynthesis, is essential for somatic embryo formation, suggesting that WRI1-mediated lipid biosynthesis plays a crucial role in the transition from vegetative to embryonic development. Our findings indicate a direct interaction between WRI1 and LEC2, which enhances the enrichment of LEC2 at downstream target genes and stimulates their induction. Besides, our data suggest that WRI1 forms a complex with LEC1, LEC2, and FUSCA3 (FUS3) to facilitate the accumulation of auxin and lipid for the somatic embryo induction, through strengthening the activation of YUCCA4 (YUC4) and OLEOSIN3 (OLE3) genes. Our results uncover a regulatory module controlled by WRI1, crucial for somatic embryogenesis. These findings provide valuable insights into our understanding of plant cell totipotency.

Efficacy and long-term outcomes of single-balloon enteroscopy-assisted treatment for biliary obstruction after choledochojejunostomy.

BACKGROUND: To evaluate the long-term efficacy of single-balloon enteroscopy endoscopic retrograde cholangiography (SBE-ERC) for the treatment of biliary obstruction and to analyze the factors affecting the recurrence of benign bilioenteric anastomotic stricture after SBE-ERC treatment. METHODS: The clinical data of patients with biliary diseases treated with SBE-ERC after choledochojejunostomy in our hospital from January 2015 to December 2021 were analyzed retrospectively for the success rates of diagnosis and treatment and the incidence of complications. Patients who were diagnosed with benign bilioenteric anastomotic stricture were followed up. The independent factors affecting recurrence were obtained by univariate and multivariate analyses using the Kaplan‒Meier method and Cox proportional hazard regression model. RESULTS: A total of 289 SBE-ERCs were performed in 165 patients. The overall success rate was 83.0% (240/289). The incidence of postoperative complications was 5.2% (15/289). The 108 successfully treated patients diagnosed with benign bilioenteric anastomotic stricture were followed up. Twenty-six percent (29/108) of patients had recurrent stricture after SBE-ERC. The biliary patency rates at 1 year, 2 years and 5 years after SBE-ERC were 90.1%, 69.3%, and 53.9%, respectively. Single-factor analysis revealed the absence of intrahepatic biliary gas imaging during endoscopy ( χ 2 =5.366, P = 0.021), a diameter of balloon dilatation during the last endoscopic treatment less than 0.8 cm ( χ 2 =4.552, P = 0.033), and the presence of a thread in the anastomosis ( χ 2 =8.921, P = 0.003) as risk factors for recurrence. A non-indwelling biliary plastic stent ( χ 2 =14.868, P < 0.001) and undergoing only one ERCP treatment ( χ 2 =13.313, P = 0.001) were risk factors for the recurrence of benign stricture after SBE-ERC resection. Multivariate analysis revealed that the absence of a stent (HR = 0.15, 95% CI 0.06-0.40, P = 0.001), absence of intrahepatic biliary gas imaging during endoscopy (HR = 0.39, 95% CI 0.17-0.91, P = 0.03) and the presence of a thread in the anastomosis (HR = 3.69, 95% CI 1.59-8.57, P = 0.002) were independent risk factors for stricture recurrence. CONCLUSIONS: Treating biliary disease after choledochojejunostomy with SBE-ERC is safe and effective, with a good immediate technical success rate and an acceptable incidence of complications. SBE-ERC has long-term efficacy in the treatment of benign bilioenteric anastomotic stricture. The absence of intrahepatic biliary gas imaging during endoscopy, non-indwelling biliary stents and the existence of anastomotic threads are independent risk factors for the recurrence of benign bilioenteric anastomotic stricture.

Comparative efficacy and safety of medical treatments for proximal humerus fractures: a systematic review and network meta-analysis.

BACKGROUND: Various surgical techniques and conservative therapies are useful tools for treating proximal humerus fractures (PHFs), but it is important to understand how to properly utilize them. Therefore, we performed a systematic review and network meta-analysis to compare and rank the efficacy and safety of medical treatments for PHF. METHODS: PubMed, Embase, the Cochrane Library, and the ClinicalTrials.gov databases were systematically searched for eligible randomized controlled trials (RCTs) from inception until June 2022. Conservative therapy-controlled or head-to-head RCTs of open reduction internal fixation (ORIF), intramedullary nailing (IMN), hemiarthroplasty (HA), and reverse total shoulder arthroplasty (RTSA) used for the treatment of adult patients with PHF were included. The surface under the cumulative ranking (SUCRA) probabilities were applied to compare and rank the effects of medical treatments for PHF. RESULTS: Eighteen RCTs involving 1,182 patients with PHF were selected for the final analysis. Mostly baseline characteristics among groups were well balanced, and the imbalanced factors only included age, injury type, medial comminution, blood loss, and cognitive function in single trial. The SUCRA probabilities found that RTSA provided the best effect on the Constant-Murley score (SUCRA: 100.0%), and the disabilities of the arm, shoulder and hand (DASH) score (SUCRA: 99.0%). Moreover, HA (SUCRA: 85.5%) and RTSA (SUCRA: 68.0%) had a relatively better effect on health-related quality of life than the other treatment modalities. Furthermore, conservative therapy (SUCRA: 84.3%) and RTSA (SUCRA: 80.7%) were associated with a lower risk of secondary surgery. Finally, the best effects on the risk of complications are varied, including infection was observed with conservative therapy (SUCRA: 94.2%); avascular necrosis was observed in HA (SUCRA: 78.1%), nonunion was observed in RTSA (SUCRA: 69.6%), and osteoarthritis was observed in HA (SUCRA: 93.9%). CONCLUSIONS: This study found that RTSA was associated with better functional outcomes, while the comparative outcomes of secondary surgery and complications varied. Optimal treatment for PHF should consider patient-specific factors.

[Evidence mapping of Chinese patent medicines in treatment of premature ventricular contractions].

This study employed evidence mapping to systematically sort out the clinical studies about the treatment of premature ventricular contractions with Chinese patent medicines and to reveal the distribution of evidence in this field. The articles about the treatment of premature ventricular contractions with Chinese patent medicines were searched against PubMed, Cochrane Library, Web of Science, CNKI, Wanfang, and VIP with the time interval from January 2016 to December 2022. Evidence was analyzed and presented by charts and graphs combined with text. According to the inclusion and exclusion criteria, 164 papers were included, including 147 interventional studies, 4 observational studies, and 13 systematic reviews. A total of 27 Chinese patent medicines were involved, in which Shensong Yangxin Capsules and Wenxin Granules had high frequency. There were off-label uses in clinical practice. In recent years, the number of articles published in this field showed a decreasing trend. Eight types of outcome indicators were used in interventional studies. Ambulatory electrocardiography, clinical response rate, safety, and echocardiography had high frequency, while the rate of ß-blocker decompensation, major cardiovascular events, and pharmaceutical economic indicators were rarely reported. The evaluation was one-sided. The low quality of the included articles reduced the reliability of the findings. In the future, the clinical use of medicines should be standardized, and the quality of clinical studies should be improved. Comprehensive clinical evaluation should be carried out to provide a sound scientific basis for the treatment of premature ventricular contractions with Chinese patent medicines.

Constructing CoO/Mo2 C Heterostructures with Interfacial Electron Redistribution Induced by Work Functions for Boosting Overall Water Splitting.

Space charge transfer of heterostructures driven by the work-function-induced built-in field can regulate the electronic structure of catalysts and boost the catalytic activity. Herein, an epitaxial heterojunction catalyst of CoO/Mo2 C with interfacial electron redistribution induced by work functions (WFs) is constructed for overall water splitting via a novel top-down strategy. Theoretical simulations and experimental results unveil that the WFs-induced built-in field facilitates the electron transfer from CoO to Mo2 C through the formed "Co─C─Mo" bond at the interface of CoO/Mo2 C, achieving interfacial electron redistribution, further optimizing the Gibbs free energy of primitive reaction step and then accelerating kinetics of hydrogen evolution reaction (HER). As expected, the CoO/Mo2 C with interfacial effects exhibits excellent HER catalytic activity with only needing the overpotential of 107 mV to achieve 10 mA cm-2 and stability for a 60-h continuous catalyzing. Besides, the assembled CoO/Mo2 C behaves the outstanding performance toward overall water splitting (1.58 V for 10 mA cm-2 ). This work provides a novel possibility of designing materials based on interfacial effects arising from the built-in field for application in other fields.

Oxygen Vacancy-Mediated CuWO4/CuBi2O4 Samples with Efficient Charge Transfer for Enhanced Catalytic Activity toward Photodegradation of Pharmacologically Active Compounds.

Photocatalytic degradation is a promising method for controlling the increasing contamination of the water environment due to pharmacologically active compounds (PHACs). Herein, oxygen vacancy (OV)-modulated Z-scheme CuWO4/CuBi2O4 hybrid systems were fabricated via thermal treatment by loading of CuWO4 nanoparticles with OVs on CuBi2O4 surfaces. The synthesized CuWO4/CuBi2O4 hybrid samples exhibited an enhanced photodegradation ability to remove PHACs under visible-light irradiation. More importantly, an optimized sample (10 wt % CuWO4/CuBi2O4) exhibited superior catalytic activity and excellent recycling stability for PHAC photodegradation. In addition, possible degradation paths for PHAC removal over the CuWO4/CuBi2O4 hybrid systems were proposed. The enhanced photocatalytic performance could be attributed to the efficient separation and transfer of photoformed charge pairs via the Z-scheme mechanism. This Z-scheme mechanism was systematically analyzed using trapping experiments of active species, ultraviolet photoelectron spectroscopy, electron spin resonance, and the photodepositions of noble metals. The findings of this study can pave the way for developing highly efficient Z-scheme photocatalytic systems for PHAC photodegradation.

Effects of ultrashort wave diathermy on skin wounds in rabbit ears.

PURPOSE: Ultrashort wave diathermy (USWD) is commonly used in diseases associated with osteoarticular and soft tissue injuries. However, while accelerating wound healing and preventing joint stiffness, there have been few reports on whether it leads to excessive hypertrophic scarring. The aim was to investigate the effects of different doses of USWD on hypertrophic scars. MATERIALS AND METHODS: A rabbit model of hypertrophic scars was used to determine which dose of USWD reduced scar hyperplasia. The scar thickness was calculated using Sirius red staining. All protein expression levels were determined by western blotting, including fibrosis, collagen deposition, and neoangiogenesis related proteins. Subsequently, flow cytometry and ELISAs were used to determine the proportions of macrophage and inflammatory levels. RESULTS: The wounds with USWD in histopathology showed the dermis was more markedly thickened in the 120 mA group, whereas the wounds with the 60 mA were less raised, comparing with the 0 mA; all detected protein levels were increased significantly, the 120 mA group comparing with the others, including heat shock, fibrosis, and neoangiogenesis, whereas the collagen deposition relative protein levels were decreased, the 60 mA group comparing with Sham group; Finally, in the proportion of macrophages and inflammatory levels the 120 mA group were the highest, and the group Sham was lower than group 60 mA. CONCLUSIONS: In hypertrophic scars, the 60 mA USWD could relieve scar formation and inflammatory reactions; however, higher doses could result in opposite consequences.

Integration of pluripotency pathways regulates stem cell maintenance in the Arabidopsis shoot meristem.

In the shoot meristem, both WUSCHEL (WUS) and SHOOT MERISTEMLESS (STM), two transcription factors with overlapping spatiotemporal expression patterns, are essential for maintaining stem cells in an undifferentiated state. Despite their importance, it remains unclear how these two pathways are integrated to coordinate stem cell development. Here, we show that the WUS and STM pathways in Arabidopsis thaliana converge through direct interaction between the WUS and STM proteins. STM binds to the promoter of CLAVATA3 (CLV3) and enhances the binding of WUS to the same promoter through the WUS-STM interaction. Both the heterodimerization and simultaneous binding of WUS and STM at two sites on the CLV3 promoter are required to regulate CLV3 expression, which in turn maintains a constant number of stem cells. Furthermore, the expression of STM depends on WUS, and this WUS-activated STM expression enhances the WUS-mediated stem cell activity. Our data provide a framework for understanding how spatial expression patterns within the shoot meristem are translated into regulatory units of stem cell homeostasis.

Application of Familial Y-STR Haplotype Mismatch Tolerance in Genealogy Inference.

OBJECTIVES: To provide a guideline for genealogy inference and family lineage investigation through a study of the mismatch tolerance distribution of Y-STR loci in Chinese Han male lineage. METHODS: Three Han lineages with clear genetic relationships were selected. YFiler Platinum PCR amplification Kit was used to obtain the typing data of 35 Y-STR loci in male samples. The variation of Y-STR haplotypes in generation inheritance and the mismatch tolerance at 1-7 kinship levels were statistically analyzed. RESULTS: Mutations in Y-STR were family-specific with different mutation loci and numbers of mutation in different lineages. Among all the mutations, 66.03% were observed on rapidly and fast mutating loci. At 1-7 kinship levels, the number of mismatch tolerance ranged from 0 to 5 on all 35 Y-STR loci, with a maximum step size of 6. On medium and slow mutant loci, the number of mismatch tolerance ranged from 0 to 2, with a maximum step size of 3; on rapidly and fast mutant loci, the number of mismatch tolerance ranged from 0 to 3, with a maximum step size of 6. CONCLUSIONS: Combined use of SNP genealogy inference and Y-STR lineage investigation, both 0 and multiple mismatch tolerance need to be considered. Family lineage with 0-3 mismatch tolerance on all 35 Y-STR loci and 0-1 mismatch tolerance on medium and slow loci can be prioritized for screening. When the number of mismatch tolerance is eligible, family lineages with long steps should be carefully excluded. Meanwhile, adding fast mutant loci should also be handled with caution.

Cell-Free Extracts from Human Fat Tissue with a Hyaluronan-Based Hydrogel Attenuate Inflammation in a Spinal Cord Injury Model through M2 Microglia/Microphage Polarization.

Treatment for spinal cord injuries (SCIs) is often ineffective because SCIs result in a loss of nerve tissue, glial scar formation, local ischemia and secondary inflammation. The current promising strategy for SCI is the combination of bioactive materials and cytokines. Bioactive materials support the injured spinal cord, stabilize the morphology, and avoid excessive inflammatory responses. Fat extract (FE) is a cell-free liquid component containing a variety of cytokines extracted from human fat tissue using mechanical methods. In this research, a biocompatible HAMC (hyaluronan and methylcellulose) loaded with FE is used to treat a model of spinal cord contusion in mice. The composite not only inhibits death of neuro- and vascular cells and leads to the preservation of neural and vascular structure, but also modulates the inflammatory phenotype of macrophages in the locally injured region. Specifically, FE promotes the polarization of macrophages from an inflammatory M1 phenotype to an anti-inflammatory M2 phenotype. During the screening of the involved pathways, it is corroborated that activation of the STAT6/Arg-1 signaling pathway is involved in macrophage M2 polarization. In summary, FE is a promising treatment for SCI, as it is easy to obtain, nonimmunogenic, and effective.

Photoexcited sulfenylation of C(sp3)-H bonds in amides using thiosulfonates.

A photoexcited sulfenylation of C(sp3)-H bonds in amides is developed for the synthesis of sulfenyl amides using thiosulfonates as a sulfur source. In the presence of easily available and inexpensive Na2-eosin Y, TBHP and K2CO3, various sulfenyl amides can be obtained under the irradiation of blue light at room temperature.

Bone marrow cells are differentiated into MDSCs by BCC-Ex through down-regulating the expression of CXCR4 and activating STAT3 signalling pathway.

Studies showed that the increase of myeloid-derived suppressor cells (MDSCs) in tumour microenvironment is closely related to the resistant treatment and poor prognosis of metastatic breast cancer. However, the effect of tumour-derived exosomes on MDSCs and its mechanism are not clear. Here, we reported that breast cancer cells (4T1)-secreted exosomes (BCC-Ex) were able to differentiate bone marrow cells into MDSCs and significantly inhibited the proliferation of T lymphocytes to provide an immunosuppressive microenvironment for cancer cells in vivo and in vitro. The number of MDSCs in bone marrow and spleen of 4T1 tumour-bearing mice and BCC-Ex infused mice was significantly higher than that of normal mice, whereas the number of T lymphocytes in spleen was significantly decreased. In addition, BCC-Ex markedly promoted the differentiation of MDSCs from bone marrow cells or bone marrow cells derived macrophages, seen as the increased expressions of MDSCs-related functional proteins Arginase-1 (Arg-1) and inducible nitric oxide synthase (iNOS). Furthermore, BCC-Ex significantly down-regulated the expressions of chemokine receptor CXCR4 and markedly up-regulated the levels of inflammatory cytokines IL-6 and IL-10 in bone marrow cells and macrophages and remarkably inhibited the division and proliferation of T cells. Importantly, CXCR4 agonist, CXCL12, could reverse the function of BCC-Ex, indicating that BCC-Ex-induced MDSCs might be dependent on the down-regulation of CXCR4. Western blot showed that BCC-Ex significantly promoted the phosphorylation of STAT3 in bone marrow cells, resulting in the inhibitions of the proliferation and apoptosis of bone marrow cells, and the aggravation of the differentiation of bone marrow cells into MDSCs.

Paenibacillus puerhi sp. nov., isolated from the rhizosphere soil of Pu-erh tea plants (Camellia sinensis var. assamica).

An aerobic, Gram-staining-positive, rod-shaped, endospore-forming and motile bacterial strain, designated SJY2T, was isolated from the rhizosphere soil of tea plants (Camellia sinensis var. assamica) collected in the organic tea garden of the Jingmai Pu-erh tea district in Pu'er city, Yunnan, southwest China. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate belonged to the genus Paenibacillus. The closest phylogenetic relative was Paenibacillus filicis DSM 23916T (98.1% similarity). The major fatty acids (> 10% of the total fatty acids) were anteiso-C15:0 and isoC16:0. The major respiratory quinone was MK-7 and the major polar lipid was diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylmonomethylethanolamine. The peptidoglycan contained glutamic acid, serine, alanine and meso-diaminopimelic acid. Genome sequencing revealed a genome size of 6.71 Mbp and a G + C content of 53.1%. Pairwise determined whole genome average nucleotide identity (gANI) values and digital DNA-DNA hybridization (dDDH) values suggested that strain SJY2T represents a new species, for which we propose the name Paenibacillus puerhi sp. nov. with the type strain SJY2T (= CGMCC 1.17156T = KCTC 43242T).

Visible-light-promoted synthesis of secondary and tertiary thiocarbamates from thiosulfonates and N-substituted formamides.

A general visible-light-promoted metal-free synthesis of secondary and tertiary thiocarbamates starting from thiosulfonates and N-substituted formamides is developed. By employing rhodamine B as a photocatalyst and tert-butyl hydroperoxide (TBHP) as an oxidant, a wide scope of thiocarbamates can be obtained through direct thiolation of acyl C-H bonds under irradiation of blue light at room temperature for 12 h.

Effects of steam-flaked grains on foals' growth and faecal microbiota.

BACKGROUND: There is little objective information concerning the effect of steam-flaked grains on foal's growth performance and faecal microbiota. To determine the effects of steam-flaked grains on foal's growth performance and faecal microbiota, faecal samples were collection from 18 foals which had been fed either corn, oat or barley diets over the 60 days of the experiment. Body weight and conformation measurements were collected. Next-generation sequencing of the V3 + V4 region of the 16 S rRNA gene was used to assess the microbial composition of faeces. Alpha diversity, Venn graph, Relative abundance and beta diversity are presented. RESULTS: There was a significantly higher larger increase in the body weight of those foals fed barley compared to either corn or oats. There were also significant changes in the Alpha diversity of the gut microbiota. The Shannon and Simpson indices were significantly higher in the barley fed group than those fed corn or oats. The Chao1 index was significantly higher in the oat fed group than the corn or barley fed groups. There were significant changes in the relative abundance of bacteria in the microbiota in terms of phylum, family and genus. The histogram of LDA value distribution showed that the 12 statistically different biomarkers of the bacteria were present. Tax4Fun function annotation clustering heat map showed that functional information was detected from 26 species of bacteria in faecal samples from the foals. CONCLUSIONS: Differences by starch sources were found in overall growth of the foals and in the faecal microbiota if either supplementary corn, oat or barley was fed. Further studies are required to determine the potential impact of the changes in the microbiota on the health and development of foals fed cereal starch of different sources.

iTRAQ- and LC-MS/MS-based quantitative proteomics reveals Pqlc2 as a potential regulator of hepatic glucose metabolism and insulin signalling pathway during fasting.

Glucose homeostasis is tightly controlled by balance between glucose production and uptake in liver tissue upon energy shortage condition. Altered glucose homeostasis contributes to the pathophysiology of metabolic disorders including diabetes and obesity. Here, we aimed to analyse the change of proteomic profile upon prolonged fasting in mice with isobaric tag for relative and absolute quantification (iTRAQ) labelling followed by liquid chromatography-mass spectrometry (LC/MS) technology. Adult male mice were fed or fasted for 16 hours and liver tissues were collected for iTRAQ labelling followed by LC/MS analysis. A total of 322 differentially expressed proteins were identified, including 189 upregulated and 133 downregulated proteins. Bioinformatics analyses, including Gene Ontology analysis (GO), Kyoto encyclopaedia of genes and genomes analysis (KEGG) and protein-protein interaction analysis (PPI) were conducted to understand biological process, cell component, and molecular function of the 322 differentially expressed proteins. Among 322 hepatic proteins differentially expressed between fasting and fed mice, we validated three upregulated proteins (Pqlc2, Ehhadh and Apoa4) and two downregulated proteins (Uba52 and Rpl37) by western-blotting analysis. In cultured HepG2 hepatocellular cells, we found that depletion of Pqlc2 by siRNA-mediated knockdown impaired the insulin-induced glucose uptake, inhibited GLUT2 mRNA level and suppressed the insulin-induced Akt phosphorylation. By contrast, knockdown of Pqlc2 did not affect the cAMP/dexamethasone-induced gluconeogenesis. In conclusion, our study provides important information on protein profile change during prolonged fasting with iTRAQ- and LC-MS/MS-based quantitative proteomics, and identifies Pqlc2 as a potential regulator of hepatic glucose metabolism and insulin signalling pathway in this process.

Human amniotic mesenchymal stem cells inhibit hepatocellular carcinoma in tumour-bearing mice.

Hepatocellular carcinoma (HCC) is the third leading cause of the cancer-related death in the world. Human amniotic mesenchymal stem cells (hAMSCs) have been characterized with a pluripotency, low immunogenicity and no tumorigenicity. Especially, the immunosuppressive and anti-inflammatory effects of hAMSCs make them suitable for treating HCC. Here, we reported that hAMSCs administrated by intravenous injection significantly inhibited HCC through suppressing cell proliferation and inducing cell apoptosis in tumour-bearing mice with Hepg2 cells. Cell tracking experiments with GFP-labelled hAMSCs showed that the stem cells possessed the ability of migrating to the tumorigenic sites for suppressing tumour growth. Importantly, both hAMSCs and the conditional media (hAMSC-CM) have the similar antitumour effects in vitro, suggesting that hAMSCs-derived cytokines might be involved in their antitumour effects. Antibody array assay showed that hAMSCs highly expressed dickkopf-3 (DKK-3), dickkopf-1 (DKK-1) and insulin-like growth factor-binding protein 3 (IGFBP-3). Furthermore, the antitumour effects of hAMSCs were further confirmed by applications of the antibodies or the specific siRNAs of DKK-3, DKK-1 and IGFBP-3 in vitro. Mechanically, hAMSCs-derived DKK-3, DKK-1 and IGFBP-3 markedly inhibited cell proliferation and promoted apoptosis of Hepg2 cells through suppressing the Wnt/ß-catenin signalling pathway and IGF-1R-mediated PI3K/AKT signalling pathway, respectively. Taken together, our study demonstrated that hAMSCs possess significant antitumour effects in vivo and in vitro and might provide a novel strategy for HCC treatment clinically.

Human umbilical cord mesenchymal stem cell-derived and dermal fibroblast-derived extracellular vesicles protect dermal fibroblasts from ultraviolet radiation-induced photoaging in vitro.

Ultraviolet B (UVB) radiation is a major cause of aging in dermal fibroblasts. Human umbilical cord mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) show antioxidant activity. In this study, the anti-aging effects of MSC-EVs on dermal fibroblast photoaging induced by UVB radiation were evaluated, and the effects of extracellular vesicles derived from dermal fibroblasts (Fb-EVs) were compared. Human umbilical cord mesenchymal stem cells and human dermal fibroblasts were cultured, and MSC-EVs and Fb-EVs were isolated and characterized. Human dermal fibroblasts were cultured in the absence or presence of different concentrations of EVs 24 hours prior to UVB radiation exposure. Cell proliferation and cell cycle were evaluated, and senescent cells and intracellular ROS were detected. The expressions of matrix metalloproteinase-1 (MMP-1), extracellular matrix protein collagen type 1 (Col-1), and antioxidant proteins such as glutathione peroxidase 1 (GPX-1), superoxide dismutase (SOD), and catalase were also analyzed. Pretreatment with MSC-EVs or Fb-EVs significantly inhibited the production of ROS induced by UVB radiation, increased dermal fibroblast proliferation, protected cells against UVB-induced cell death and cell cycle arrest, and remarkably decreased the percentage of aged cells. Pretreatment with MSC-EVs or Fb-EVs promoted the expressions of GPX-1 and Col-1 and decreased the expression of MMP-1. Both MSC-EVs and Fb-EVs protected dermal fibroblasts from UVB-induced photoaging, likely through their antioxidant activity.

Ratiometric assay of mercury ion based on nitrogen-doped carbon dots with two different optical signals: second-order scattering and fluorescence.

Ratiometric assays, which can effectively surmount external interference, have attracted extensive research interests. Herein, a novel ratiometric sensing platform for Hg2+ is designed based on nitrogen-doped carbon dots (N-CDs) with two different optical signals. Under a single excitation, N-CDs have two emission peaks around 668 nm and 412 nm, which are second-order scattering and fluorescence, respectively. Upon the addition of Hg2+, the weak scattering emission at 668 nm can be increased apparently, while the strong fluorescence intensity at 412 nm is weakened. Moreover, the ratio of scattering intensity to fluorescence intensity is linearly dependent on Hg2+ concentration (0.1-10 µM and 10-30 µM, respectively), and the detection limit is 66 nM. In addition, the ratiometric sensing mechanism is investigated in detail, which is due to the combined effect of aggregation-induced fluorescence quenching and scattering enhancement. Furthermore, the developed sensing approach holds a promising application for Hg2+ detection in actual samples. Graphical abstract.