miRNA-21-5p is an important contributor to the promotion of injured peripheral nerve regeneration using hypoxia-pretreated bone marrow-derived neural crest cells

Our previous study found that rat bone marrow–derived neural crest cells(acting as Schwann cell progenitors)have the potential to promote long-distance nerve repair.Cell-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular communication.Nevertheless,the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain unclear.To investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves,we collected conditioned culture medium from hypoxia-pretreated neural crest cells,and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose deprivation.The mRNA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest cells.We performed RNA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest cells.Subsequently,to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons,we used a microfluidic axonal dissociation model of sensory neurons in vitro,and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons,which was greatly dependent on loaded miR-21-5p.Finally,we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb,as well as muscle tissue morphology of the hind limbs,were obviously restored.These findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in miRNA-21-5p.miRNA-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell secretome.This helps to explain the mechanism of action of the secretome and extracellular vesicles of neural crest cells in repairing damaged peripheral nerves,and also promotes the application of miR-21-5p in tissue engineering regeneration medicine.

Effect of nuclear factor-κB and angiotensin Ⅱ receptor type 1 on the pathogenesis of rat non-alcoholic fatty liver disease

AIM: To investigate the roles of nuclear factor(NF)-κB and angiotensin Ⅱ receptor type 1(AT1R) in the pathogenesis of non-alcoholic fatty liver disease(NAFLD).METHODS: Forty-two healthy adult male SpragueDawley rats were randomly divided into three groups:the control group(normal diet), the model group,and the intervention group(10 wk of a high-fat diet feeding, followed by an intraperitoneal injection of PDTC); 6 rats in each group were sacrificed at 6, 10,and 14 wk. After sacrifice, liver tissue was taken,paraffin sections of liver tissue specimens were prepared, hematoxylin and eosin(HE) staining was performed, and pathological changes in liver tissue(i.e., liver fibrosis) were observed by light microscopy.NF-κB expression in liver tissue was detected by immunohistochemistry, and the expression of AT1 R in the liver tissue was detected by reverse transcriptionpolymerase chain reaction(RT-PCR). The data are expressed as mean ± SD. A two-sample t test was used to compare the control group and the model group at different time points, paired t tests were used to compare the differences between the intervention group and the model group, and analysis of variance was used to compare the model group with the control group. Homogeneity of variance was analyzed with single factor analysis of variance. H variance analysis was used to compare the variance. P < 0.05 wasconsidered statistically significant.RESULTS: The NAFLD model was successful after 6wk and 10 wk. Liver fibrosis was found in four rats in the model group, but in only one rat in the intervention group at 14 wk. Liver steatosis, inflammation, and fibrosis were gradually increased throughout the model. In the intervention group, the body mass,rat liver index, serum lipid, and transaminase levels were not increased compared to the model group.In the model group, the degree of liver steatosis was increased at 6, 10, and 14 wk, and was significantly higher than in the control group(P < 0.01). In the model group, different degrees of liver cell necrosis were visible and small leaves, punctated inflammation,focal necrosis, and obvious ballooning degeneration were observed. Partial necrosis and confluent necrosis were observed. In the model group, liver inflammatory activity scores at 6, 10, and 14 wk were higher than in the control group(P < 0.01). Active inflammation in liver tissue in the intervention group was lower than in the model group(P < 0.05). HE staining showed liver fibrosis only at 14 wk in 4/6 rats in the model group and in 1/6 rats in the intervention group. NF-κB positive cells were stained yellow or ensemble yellow,and NF-κB was localized in the cytoplasm and/or nucleus. The model group showed NF-κB activation at6, 10, and 14 wk in liver cells; at the same time points,there were statistically significant differences in the control group(P < 0.01). Over time, NF-κB expression increased; this was statistically lower(P < 0.05) at14 weeks in the intervention group compared to the model group, but significantly increased(P < 0.05)compared with the control group; RT-PCR showed that AT1 R mRNA expression increased gradually in the model group; at 14 wk, the expression was significantly different compared with expression at 10 weeks as well as at 6 weeks(P < 0.05). In the model group, AT1 R mRNA expression was significantly higher than at the same time point in the control group(P <0.01).CONCLUSION: With increasing severity of NAFLD,NF-κB activity is enhanced, and the inhibition of NF-κB activity may reduce AT1 R mRNA expression in NAFLD.

Correlation between preoperative systemic immune inflammation index, nutritional risk index, and prognosis of radical resection of liver cancer

BACKGROUND Radical surgery is the most commonly used treatment for hepatocellular carcinoma(HCC).However,the surgical effect remains not ideal,and prognostic evaluation is insufficient.Furthermore,clinical intervention is rife with uncertainty and not conducive to prolonging patient survival.AIM To explore correlations between the systemic immune inflammatory index(SII)and geriatric nutritional risk index(GNRI)and HCC operation prognosis.METHODS This retrospective study included and collected follow up data from 100 HCC.Kaplan–Meier survival curves were used to analyze the correlation between SII and GNRI scores and survival.SII and GNRI were calculated as follows:SII=neutrophil count×platelet count/lymphocyte count;GNRI=[1.489×albumin(g/L)+41.7×actual weight/ideal weight].We analyzed the predictive efficacy of the SII and GNRI in HCC patients using receiver operating characteristic(ROC)curves,and the relationships between the SII,GNRI,and survival rate using Kaplan–Meier survival curves.Cox regression analysis was utilized to analyze independent risk factors influencing prognosis.RESULTS After 1 year of follow-up,24 patients died and 76 survived.The area under the curve(AUC),sensitivity,specificity,and the optimal cutoff value of SII were 0.728(95%confidence interval:0.600-0.856),79.2%,63.2%,and 309.14,respectively.According to ROC curve analysis results for predicting postoperative death in HCC patients,the AUC of SII and GNRI combination was higher than that of SII or GNRI alone,and SII was higher than that of GNRI(P<0.05).The proportion of advanced differentiated tumors,tumor maximum diameter(5–10 cm,>10 cm),lymph node metastasis,and TNM stage III-IV in patients with SII>309.14 was higher than that in patients with SII≤309.14(P<0.05).The proportion of patients aged>70 years was higher in patients with GNRI≤98 than that in patients with GNRI>98(P<0.05).The 1-year survival rate of the SII>309.14 group(compared with the SII≤309.14 group)and GNRI≤98 group(compared with the GNRI>98 group)was lower(P<0.05).CONCLUSION The prognosis after radical resection of HCC is related to the SII and GNRI and poor in high SII or low GNRI patients.

Peripheral nerve fibroblasts secrete neurotrophic factors to promote axon growth of motoneurons

Peripheral nerve fibroblasts play a critical role in nerve development and regeneration.Our previous study found that peripheral nerve fibroblasts have different sensory and motor phenotypes.Fibroblasts of different phenotypes can guide the migration of Schwann cells to the same sensory or motor phenotype.In this study,we analyzed the different effects of peripheral nerve-derived fibroblasts and cardiac fibroblasts on motoneurons.Compared with cardiac fibroblasts,peripheral nerve fibroblasts greatly promoted motoneuron neurite outgrowth.Transcriptome analysis results identified 491 genes that were differentially expressed in peripheral nerve fibroblasts and cardiac fibroblasts.Among these,130 were significantly upregulated in peripheral nerve fibroblasts compared with cardiac fibroblasts.These genes may be involved in axon guidance and neuron projection.Three days after sciatic nerve transection in rats,peripheral nerve fibroblasts accumulated in the proximal and distal nerve stumps,and most expressed brain-derived neurotrophic factor.In vitro,brain-derived neurotrophic factor secreted from peripheral nerve fibroblasts increased the expression ofβ-actin and F-actin through the extracellular regulated protein kinase and serine/threonine kinase pathways,and enhanced motoneuron neurite outgrowth.These findings suggest that peripheral nerve fibroblasts and cardiac fibroblasts exhibit different patterns of gene expression.Peripheral nerve fibroblasts can promote motoneuron neurite outgrowth.

高效析氢用花状MoS_(x)Se_(2-x)纳米复合材料的简便合成

为了解决MoSe_(2)导电性差和活性位点有限的问题,通过简便水热工艺合成具有缺陷的三元MoS_(x)Se_(2−x)纳米片。结果表明,硫元素的引入,不仅提高了其电子转移能力,而且提供了更多的电催化活性位点。因此,优化后S/Se摩尔比为1:1的MoS_(x)Se_(2-x)(MoSSe)具有优异的电催化析氢(HER)性能,其Tafel斜率仅为47 mV/dec,在−10 mA/cm^(2)下具有较低的过电位(−165 mV),并且具有良好的耐久性。这项工作为更好地理解多因素调控在设计和合成MoSe_(2)基催化剂以提高其电化学活性方面提供了一条额外的途径。

Experimental Effect of Umbilical Cord Mesenchymal Stem Cells on Stress Urinary Incontinence Rats Model and Efficient Tracking in vivo with MRI

Objective To assess the effect of intra-sphincteric injections of human umbilical cord mesenchymal stem cells(HUMSCs)on leak point pressure(LPP)changes in an animal model of stress urinary incontinence(SUI).Meanwhile,to investigate in vivo MRI tracking HUMSCs in SUI rats using a clinically available paramagnetic contrast agent(Gd-DTPA)and commercially available effentence transfection reagents..Materials and Methods HUMSCs were dual labeled with Gd-DTPA and PKH26,the labeling efficiency and longevity of Gd-DTPA maintenance were measured and cell viability and proliferation were assessed.39 female Sprague–Dawley SUI rats.12 normal rats and 12 SUI rats received periurethral injection of PBS and 12 SUI rats were given periurethral injection of dual labeled HUMSCs.3 SUI rat sreceived periurethral injection of u nlabeled HUMSCs.Six weeks after injection,LPP was undertaken in animals.All rats were sacrificed and frozen urethra sections were submitted to pathology and immunohistochemistry assessment.Results The labeling efficiency of Gd-DTPA was up to 80%,the labeling procedure did not influence cell viability and proliferation.The signal intensity on T1-weighted imaging and T1 values of labeled cells were significantly higher than those of unlabeled cells.In vitro,differentiated HUMSCs expressed myosin heavy chain(MHC)and desmin,markers of striated muscles.In vivo,immunohistochemistry of rat urethras revealed dual labeled HUMSCs in situ and at the injection site.LPP was significantly improved in animals injected with HUMSCs.Atrophic urethras with implanted HUMSCs were positively stained for MHC and desmin.The distribution and migration of labeled cells could be tracked by MRI more than 14 days after t ransplantation.Conclusion HUMSCs have the ability to differentiate striated muscles,as demonstrated by MHC and desmin expression.Periurethral injection of HUMSCs in an animal model of SUI restored the damaged external urethral sphincter and significantly improved LPP.MRI can track Gd-DTPA–labled HUMSCs in an animal model of SUI in vivo.

Antibiotic usage in Chinese children: a point prevalence survey

Background Children as a population have high antimicrobial prescribing rates which may lead to high resistance of bacteria according to data from some single-center surveys of antibiotic prescribing rates in China. The acquirement of baseline data of antibiotic prescribing is the basis of developing intervention strategies on inappropriate antimicrobial prescriptions. Few studies show clearly the pattern and detailed information on classes of antibiotics and distribution of indications of antibiotic prescriptions in children in China. This study aims to assess the antibiotic prescribing patterns among children and neonates hospitalized in 18 hospitals in China. Methods A 24-hour point prevalence survey on antimicrobial prescribing was conducted in hospitalized neonates and chil-dren in China from December 1st, 2016 to February 28th, 2017. Information on the antibiotic use of patients under 18 years of age who were administered one or more on-going antibiotics in the selected wards over a 24-hour period was collected. These data were submitted to the GARPEC (Global Antimicrobial Resistance, Prescribing and Efficacy in Children and Neonates) web-based application ( https ://pidrg -datab ase.sgul.ac.uk/redca p/ ). For statistical analysis, Microsoft Excel 2007 and SPSS 22.0 were used. Results The antibiotic data were collected in 35 wards in 18 hospitals from 9 provinces. In total, 67.76% (975/1439) of the patients (n = 1439) were given at least one antibiotic, including 58.1% (173/298) of neonates (n = 298) and 70.3% (802/1141) of children (n = 1141). In neonates, the three most frequently prescribed antibiotics were third-generation cephalosporins (41.7%), penicillins plus enzyme inhibitor (23.8%), and carbapenems (11.2%). In children, the three most frequently pre-scribed antibiotics were third-generation cephalosporins (35.5%), macrolides (23.2%), and penicillins plus enzyme inhibi-tors (15.9%). The most common indication for antibiotics was proven or probable bacterial lower respiratory tract infection (30.9% in neonates and 66.6% in children). Conclusions Antibiotics are commonly prescribed in the Chinese children population. It is likely that the third-generation cephalosporins and macrolides are currently overused in Chinese children. Efforts must be made to ensure safe and appropri-ate antibiotic prescribing to reduce and prevent the future development of antibiotic resistance.

Discovery and identification of quality markers of Sparganii Rhizoma based on zebrafish thrombosis model

Objective:The aim of the present study was to determine the quality marker(Q-Markers)of Sparganii Rhizoma against thrombus through an integration of investigations on its antithrombotic effect,content determination and spectrum-effect correlation analysis.Methods:Based on the concept of Q-Marker,Sparganii Rhizoma was investigated for the identification of chemical component.The pharmacological effects on arachidonic acid-induced thrombosis in zebrafish were also investigated.The material basis in ethanol extract was determined by HPLC-UV.Furthermore,the potential Q-Markers were analyzed and predicted according to the effect-chemical correlation analysis.Finally,the anti-thrombotic Q-Markers were verified through the anti-thrombotic test of monomer components.Results:The model of thrombosis zebrafish was established with larvae exposed to 100 mmol/L arachidonic acid for 1 h.Nine ingredients in Sparganii Rhizoma were identified as 5-hydroxymethylfurfural,vanillic acid,ferulic acid,p-hydroxybenzaldehyde,p-hydroxybenzoic acid,vanillin,protocatechuic acid,p-coumaric acid and isoferulic acid.According to the determination effect of zebrafish thrombosis model and HPLC content analysis results,all the other contents present positive correlation except 5-hydroxymethylfurfural,and the P values of three representative potential Q-Markers(ferulic acid,protocatechuic acid and p-coumaric acid)were 0.002,0.001 and 0.026,respectively.Conclusion:Sparganii Rhizoma showed a dose-dependent effect on the recovery of reducing cardiac red blood cell on zebrafish model.Three phenolic acids(ferulic acid,protocatechuic acid and p-coumaric acid)were proved to possess the anti-thrombotic effects which could be regarded as the potential QMarkers for quality assessment of Sparganii Rhizoma.

Synthesis,Structure and Magnetic Behavior of a Novel Series of Trinuclear Windwheel Complexes

A new family of trinuclear windwheel complexes with molecular formula [M^(II)_(3)(tpa)_(3)(μ-ttc)](ClO_(4))_(3)·n(sol) (ttc = 1,3,5-triazine-2,4,6-trithiol;tpa = tris(2-pyridylmethyl)amine;M = Mn,n = 2,sol = CH_(3)CN,1;M = Co,n = 1,sol = CH_(3)CN,2;M = Ni,n = 0,3) were synthesized and characterized.Single-crystal X-ray diffraction revealed that three metal centers in 1—3 are connected by ttc bridge,forming a regular triangular MII3 core.Each metal center is bonded by chelating S,N atoms from ttc and by N atoms from tpa.Magnetic studies showed that 1—3 displayed antiferromagnetic behavior and further gave the easy-axis anisotropy (D = −0.77 cm^(−1) for 1 and −8.13 cm^(−1) for 2) and easy-plane anisotropy (D = 5.08 cm^(−1) for 3).Moreover,2 exhibited field-induced slow magnetic relaxation behavior and their effective energy barriers were roughly evaluated Ueff = 6.9 K.