miR-145a-5p/Plexin-A2 promotes the migration of OECs and transplantation of miR-145a-5p engineered OECs enhances the functional recovery in rats with SCI.

BACKGROUND: Olfactory ensheathing cells (OECs) serve as a bridge by migrating at the site of spinal cord injury (SCI) to facilitate the repair of the neural structure and neural function. However, OEC migration at the injury site not only faces the complex and disordered internal environment but also is closely associated with the migration ability of OECs. METHODS: We extracted OECs from the olfactory bulb of SD rats aged <7 days old. We verified the micro ribonucleic acid (miR)-145a-5p expression level in the gene chip after SCI and OEC transplantation using quantitative reverse transcription (qRT)-polymerase chain reaction (PCR). The possible target gene Plexin-A2 of miR-145a-5p was screened using bioinformatics and was verified using dual-luciferase reporter assay, Western blot, and qRT-PCR. The effect of miR-145a-5p/plexin-A2 on OEC migration ability was verified by wound healing assay, Transwell cell migration assay, and immunohistochemistry. Nerve repair was observed at the injured site of the spinal cord after OEC transplantation using tissue immunofluorescence and magnetic resonance imaging, diffusion tensor imaging, and the Basso-Beattie-Bresnahan locomotor rating scale were further used for imaging and functional evaluation. RESULTS: miR-145a-5p expression in the injured spinal cord tissue after SCI considerably decreased, while Plexin-A2 expression significantly increased. OEC transplantation can reverse miR-145a-5p and Plexin-A2 expression after SCI. miR-145a-5p overexpression enhanced the intrinsic migration ability of OECs. As a target gene of miR-145a-5p, Plexin-A2 hinders OEC migration. OEC transplantation overexpressing miR-145a-5p after SCI can increase miR-145a-5p levels in the spinal cord, reduce Plexin-A2 expression in the OECs and the spinal cord tissue, and promote OEC migration and distribution at the injured site. OEC transplantation overexpressing miR-145a-5p can promote the repair of neural morphology and neural function. CONCLUSIONS: Our study demonstrated that miR-145a-5p could promote OEC migration by down-regulating the target gene Plexin-A2, and transplantation of miR-145a-5p engineered OECs was beneficial to enhance neural structural and functional recovery in SCI rats.

ZIM3 activation of CCL25 expression in pulmonary metastatic nodules of osteosarcoma recruits M2 macrophages to promote metastatic growth.

Tumor-associated macrophages (TAMs) play an important role in tumor growth and metastasis. However, the involvement of TAMs infiltration in pulmonary osteosarcoma (OS) metastasis remains poorly understood. Therefore, the effect of OS cells on macrophages migration was investigated by in vivo and in vitro experiments to evaluate the infiltration and mechanism of TAMs in pulmonary OS metastases. The results showed that the zinc finger protein ZIM3 was upregulated in OS cells than in osteoblasts and activated the expression of CCL25, which subsequently promoted the migration of M2 macrophages. CCL25 or ZIM3 silencing in OS cells inhibited the infiltration of M2 macrophages and the formation of pulmonary metastatic nodules in a mouse model of pulmonary OS metastasis and prolonged the survival of the mice. Furthermore, bioinformatics analyses revealed that CCL25 and ZIM3 expressions are negatively correlated with the prognosis of OS patients. In conclusion, this study found that a large number of M2 TAMs were recruited into pulmonary metastatic nodules of OS through the activation of the ZIM3-CCL25 axis in OS cells, thereby facilitating OS metastasis. Therefore, the suppression of ZIM3-CCL25-induced recruitment of M2 TAMs to the metastatic sites might be considered as a therapeutic approach to inhibit the growth of pulmonary OS metastases.

Orosomucoid proteins limit endoplasmic reticulum stress in plants.

Sphingolipids are cell membrane components and signaling molecules that induce endoplasmic reticulum (ER) stress responses, but the underlying mechanism is unknown. Orosomucoid proteins (ORMs) negatively regulate serine palmitoyltransferase activity, thus helping maintain proper sphingolipid levels in humans, yeast, and plants. In this report, we explored the roles of ORMs in regulating ER stress in Arabidopsis thaliana. Loss of ORM1 and ORM2 function caused constitutive activation of the unfolded protein response (UPR), as did treatment with the ceramide synthase inhibitor Fumonisin B1 (FB1) or ceramides. FB1 treatment induced the transcription factor bZIP28 to relocate from the ER membrane to the nucleus. The transcription factor WRKY75 positively regulates the UPR and physically interacted with bZIP28. We also found that the orm mutants showed impaired ER-associated degradation (ERAD), blocking the degradation of misfolded MILDEW RESISTANCE LOCUS-O 12 (MLO-12). ORM1 and ORM2 bind to EMS-MUTAGENIZED BRI1 SUPPRESSOR 7 (EBS7), a plant-specific component of the Arabidopsis ERAD complex, and regulate its stability. These data strongly suggest that ORMs in the ER membrane play vital roles in the UPR and ERAD pathways to prevent ER stress in Arabidopsis. Our results reveal that ORMs coordinate sphingolipid homeostasis with ER quality control and play a role in stress responses.

FDM-assisted opposite two-way OA-CEAS system employing four lasers for simultaneous multi-species detection.

An FDM-assisted opposite two-way OA-CEAS system is reported in this paper. Compared with the traditional OA-CEAS system with one-way transmission configuration, the new system has two main advantages. One of the advantages is that four lasers can be employed for simultaneous measurements of multiple species in this system. Another advantage is the combination of the silver-coated concave spherical mirror and the narrow bandpass filter employed to realize the opposite two-way transmission in the optical cavity which can also serve as a re-injection mirror and optical enhancement gotten for free in the system. The performance of the system is demonstrated by simultaneous measurements of CO, CO2, C2H4, and CH4. This work highlights a new strategy for simultaneous detection by using four lasers in a single optical integrated cavity, which can improve the utilization rate of the optical cavity and reduce the cost for multiple gas species sensing.

Sulfur dioxide derivatives aggravated ovalbumin-induced asthma through targeting TRPV1 and tight junctions.

This study aimed to investigate the effects of sulfur dioxide (SO2) derivatives on asthma induced by ovalbumin (OVA). Sprague Dawley rats were sensitized to and challenged with OVA and SO2 derivatives (NaHSO3 and Na2SO3, 1:3 M/M) to establish 28-day (short-term) and 42-day (long-term) asthma models. Exposure to SO2 derivatives aggravated asthma and hence, promoted lung injury in OVA-induced asthma. In addition, it upregulated the protein expression of TRPV1 and downregulated the expression of tight junctions (TJs). These changes were dose-dependent and were more pronounced in the presence of a high concentration of SO2 derivatives. In vitro, SO2 derivatives also increased the calcium influx and TRPV1 protein expression, and decreased TJ expression. Besides, no significant difference in the TJ expression was found between the WT and TRPV1-/- mice. The underlying mechanism might be related to regulating the effects of TRPV1 and TJs.

Jasmonates modulate sphingolipid metabolism and accelerate cell death in the ceramide kinase mutant acd5.

Sphingolipids are structural components of the lipid bilayer that acts as signaling molecules in many cellular processes, including cell death. Ceramides, key intermediates in sphingolipid metabolism, are phosphorylated by the ceramide kinase ACCELERATED CELL DEATH5 (ACD5). The loss of ACD5 function leads to ceramide accumulation and spontaneous cell death. Here, we report that the jasmonate (JA) pathway is activated in the Arabidopsis (Arabidopsis thaliana) acd5 mutant and that methyl JA treatment accelerates ceramide accumulation and cell death in acd5. Moreover, the double mutants of acd5 with jasmonate resistant1-1 and coronatine insensitive1-2 exhibited delayed cell death, suggesting that the JA pathway is involved in acd5-mediated cell death. Quantitative sphingolipid profiling of plants treated with methyl JA indicated that JAs influence sphingolipid metabolism by increasing the levels of ceramides and hydroxyceramides, but this pathway is dramatically attenuated by mutations affecting JA pathway proteins. Furthermore, we showed that JAs regulate the expression of genes encoding enzymes in ceramide metabolism. Together, our findings show that JAs accelerate cell death in acd5 mutants, possibly by modulating sphingolipid metabolism and increasing ceramide levels.

Antitumor Activities for Two Pt(II) Complexes of Tropolone and 8-Hydroxyquinoline Derivative.

The reactions of cis-Pt(DMSO)2Cl2 and tropolone (HL) with 8-hydroxyquinoline (HQ) or 2-methyl-8-hydroxyquinoline (HMQ) gave [Pt(Q)(L)] (1) and [Pt(MQ)(L)] (2), which present mononuclear structures with their Pt(II) ions four-coordinated in square planar geometries. Their in vitro biological properties were evaluated by MTT assay, which showed a remarkable cytotoxic activity on the cancer cell lines. 1 shows higher cytotoxic activities on tumor cells such as T24, HeLa, A549, and NCI-H460 than complex 2 and cisplatin, with IC50 values <16 µM. Among them, an IC50 value of 3.6 ± 0.63 µM was found for complex 1 against T24 cells. It presented a tuning cytotoxic activity by substitution groups on 8-hydroxyquinoline skeleton. In our case, the substitution groups of -H are much superior to -CH3 against tumor cells. It revealed that both complexes can induce cell apoptosis by decreasing the potential of a mitochondrial membrane, enhancing reactive oxygen species and increasing Ca2+ levels of T24 cells. The T24 cell cycle can be arrested at G2 and G1 phases by complexes 1 and 2, respectively, with an upregulation for P21 and P27 expression levels and a down-regulation for cyclin A, CDK1, Cdc25A, and cyclin B expression levels. Furthermore, complex 1 exhibits satisfactory in vivo antitumor activity as revealed by the tumor inhibitory rate and the tumor weight change as well as by the cute toxicity assay and renal pathological examinations, which is close to cisplatin and much better than complex 2. All of these suggest that 1 might be a potential candidate for developing into a safe and effective anticancer agent.

Salt Enhances Disease Resistance and Suppresses Cell Death in Ceramide Kinase Mutants.

Sphingolipids act as structural components of cellular membranes and as signals in a variety of plant developmental processes and defense responses, including programmed cell death. Recent studies have uncovered an interplay between abiotic or biotic stress and programmed cell death. In a previous study, we characterized an Arabidopsis (Arabidopsis thaliana) cell-death mutant, accelerated cell death5 (acd5), which accumulates ceramides and exhibits spontaneous cell death late in development. In this work, we report that salt (NaCl) treatment inhibits cell death in the acd5 mutant and prevents the accumulation of sphingolipids. Exogenous application of abscisic acid (ABA) and the salicylic acid (SA) analog benzothiadiazole demonstrated that the effect of NaCl was partly dependent on the antagonistic interaction between endogenous SA and ABA. However, the use of mutants deficient in the ABA pathway suggested that the intact ABA pathway may not be required for this effect. Furthermore, pretreatment with salt enhanced the resistance response to biotic stress, and this enhanced resistance did not involve the pathogen-associated molecular pattern-triggered immune response. Taken together, our findings indicate that salt inhibits sphingolipid accumulation and cell death in acd5 mutants partly via a mechanism that depends on SA and ABA antagonistic interaction, and enhances disease resistance independent of pattern-triggered immune responses.

A Pyrimidin-Like Plant Activator Stimulates Plant Disease Resistance and Promotes the Synthesis of Primary Metabolites.

Plant activators are chemicals that induce plant defense responses to various pathogens. Here, we reported a new potential plant activator, 6-(methoxymethyl)-2-[5-(trifluoromethyl)-2-pyridyl] pyrimidin-4-ol, named PPA2 (pyrimidin-type plant activator 2). Unlike the traditional commercial plant activator benzothiadiazole S-methyl ester (BTH), PPA2 was fully soluble in water, and it did not inhibit plant growth or root system development in rice (Oryza sativa). PPA2 pretreatment significantly increased plant resistance against bacterial infection in both Arabidopsis and rice, in conjunction with increases in the level of jasmonoyl-isoleucine and 12-oxo-phytodienoic acid. In addition, metabolite profiling indicated that BTH significantly reduced the abundance of various primary metabolites in rice seedlings, including most amino acids, sugars, and organic acids; by contrast, PPA2 promoted their synthesis. Our results thus indicate that PPA2 enhances plant defenses against bacterial infection through the jasmonic acid pathway, and that as a water-soluble compound that can promote the synthesis of primary metabolites it has broad potential applications in agriculture.

The effect of dissolved oxygen concentration on long-term stability of partial nitrification process.

Dissolved oxygen (DO) concentration is regarded as one of the crucial factors to influence partial nitrification process. However, achieving and keeping stable partial nitrification under different DO concentrations were widely reported. The mechanism of DO concentration influencing partial nitrification is still unclear. Therefore, in this study two same sequencing batch reactors (SBRs) cultivated same seeding sludge were built up with real-time control strategy. Different DO concentrations were controlled in SBRs to explore the effect of DO concentration on the long-term stability of partial nitrification process at room temperature. It was discovered that ammonium oxidation rate (AOR) was inhibited when DO concentration decreased from 2.5 to 0.5 mg/L. The abundance of Nitrospira increased from 1011.5 to 1013.7 copies/g DNA, and its relative percentage increased from 0.056% to 3.2% during 190 operational cycles, causing partial nitrification gradually turning into complete nitrification process. However, when DO was 2.5 mg/L the abundance of Nitrospira was stable and AOB was always kept at 1010.7 copies/g DNA. High AOR was maintained, and stable partial nitrification process was kept. Ammonia oxidizing bacteria (AOB) activity was significantly higher than nitrite oxidizing bacteria (NOB) activity at DO of 2.5 mg/L, which was crucial to maintain excellent nitrite accumulation performance.

L-carnitine ameliorated fasting-induced fatigue, hunger, and metabolic abnormalities in patients with metabolic syndrome: a randomized controlled study.

BACKGROUND: The present study aimed to determine that whether L-carnitine infusion could ameliorate fasting-induced adverse effects and improve outcomes. METHOD: In this 7-day, randomized, single-blind, placebo-controlled, pilot study, 15 metabolic syndrome (MetS) patients (11/4 F/M; age 46.9 ± 9.14 years; body mass index [BMI] 28.2 ± 1.8 kg/m2) were in the L-carnitine group (LC) and 15 (10/5 F/M; age 46.8 ± 10.9 years; BMI 27.1 ± 2.3 kg/m2) were in the control group (CT). All participants underwent a 5-day modified fasting therapy introduced with 2-day moderate calorie restriction. Patients in the LC group received 4 g/day of intravenous L-carnitine, while patients in the CT group were injected with saline. Blood pressure (BP), anthropometric characteristics, markers of liver function, metabolic indices (plasma glucose, lipid profiles, uric acid, free fatty acid and insulin) and hypersensitivity C-reactive protein were measured. Perceived hunger was recorded daily by self-rating visual analogue scales. Fatigue was evaluated by Wessely and Powell scores. RESULTS: In contrast to the CT group, total cholesterol, alanine aminotransferase, systolic and diastolic BP did not change significantly in the LC group after prolonged fasting. There were significant differences in weight loss (LC -4.6 ± 0.9 vs. CT -3.2 ± 1.1 kg, P = 0.03), and waist circumference (LC -5.0 ± 2.2 vs. CT -1.7 ± 1.16 cm, P < 0.001), waist hip ratio (LC -0.023 ± 0.017 vs. CT 0.012 ± 0.01, P < 0.001), insulin concentration (LC -9.9 ± 3.58 vs. CT -6.32 ± 3.44 µU/mL, P = 0.046), and γ-glutamyltransferase concentration (LC -7.07 ± 6.82 vs. CT -2.07 ± 4.18, P = 0.024). Perceived hunger scores were significantly increased (P < 0.05) in the CT group during starvation, which was alleviated with L-carnitine administration in the LC group. Physical fatigue (LC -3.2 ± 3.17 vs. CT 1.8 ± 2.04, P < 0.001) and fatigue severity (LC -11.6 ± 8.38 vs. CT 8.18 ± 7.32, P < 0.001) were significantly reduced in the LC group but were aggravated in the CT group. CONCLUSION: Intravenous L-carnitine can ameliorate fasting-induced hunger, fatigue, cholesterol abnormalities and hepatic metabolic changes and facilitate fasting-induced weight loss in MetS patients. TRIAL REGISTRATION: ChiCTR-TNRC-12002835.

Chloride salt enhances plant resistance to biotic stresses.

Biotic stresses caused by bacterial and fungal pathogens damage crops; identifying treatments that enhance disease resistance provides important information for understanding plant defenses and sustainable agriculture. Salt stress affects crop yields worldwide; however, studies have focused on the toxic sodium ion, leaving the effects of the chloride ion unclear. In this study, we found that irrigation with a combination of chloride salts (MgCl2, CaCl2, and KCl) suppressed the cell death phenotype of the ceramide kinase mutant acd5. Chloride salt pre-irrigation also significantly limited the cell death caused by Pseudomonas syringae pv maculicola infection and inhibited the multiplication of this bacterial pathogen in a mechanism partially dependent on the salicylic acid pathway. Moreover, chloride salt pre-irrigation improved plant defenses against the fungal pathogen challenge, confining the lesion area caused by Botrytis cinerea infection. Furthermore, the growth of herbivorous larvae of Spodoptera exigua was retarded by feeding on chloride salt irrigated plants. Thus, our data suggest that treatment with Cl- increases broad spectrum resistance to biotic challenges.

Integrated evaluation of biomechanical and biological properties of the biomimetic structural bone scaffold: Biomechanics, simulation analysis, and osteogenesis.

A porous structure is essential for bone implants because it increases the bone ingrowth space and improves mechanical and biological properties. The biomimetically designed porous Voronoi scaffold can reconstruct the structure and function of cancellous bone; however, its comprehensive properties need to be investigated further. In this study, algorithms based on scaling factors were used to design the Voronoi scaffolds. Classic approaches, such as computer-aided design and the implicit surface method, have been used to design Diamond, Gyroid, and I-WP scaffolds as controls. All scaffolds were prepared by selective laser melting of titanium alloys and three-dimensional printing. Mechanical tests, finite element analysis, and in vitro and in vivo experiments were performed to investigate the biomechanical, cytologic, and osteogenic performance of the scaffolds, while computational fluid dynamics simulations were used to explore the underlying mechanisms. Diamond scaffolds have a better loading capacity, and the mechanical behaviors and fluid flow of Voronoi scaffolds are similar to those of the human trabecular bone. Cells showed more proliferation and distribution on the Diamond and Voronoi scaffolds and exhibited evident differentiation on Gyroid and Voronoi scaffolds. Bone formation was apparent on the inner part of the Gyroid, the outer part of the I-WP, and the entire Diamond and Voronoi scaffolds. The hydrodynamic properties and stimulus response of cells influenced by the porous structure account for the varied biological performance of the scaffolds. The Voronoi scaffolds with bionic mechanical behavior and an appropriate hydrodynamic response exhibit evident cell growth and osteogenesis, making them preferable for porous structural bone implants.

Biocompatibility and osteointegration capability of ß-TCP manufactured by stereolithography 3D printing: In vitro study.

Beta-tricalcium phosphate (ß-TCP) bioceramics have an inorganic composition similar to the human bone. While conventional methods can only produce ceramic scaffolds with poor controllability, the advancement of 3D-printing, especially stereolithography, made it possible to manufacture controllable, highly precise, micropore ceramic scaffolds. In this study, the stereolithography was applied to produce ß-TCP bioceramics, while ZrO2, Al2O3, Ti6Al4V, and polyetheretherketone (PEEK) were used as controls. Phase analysis, water contact angle tests, and Micro-CT were applied to evaluate the surface properties and scaffold. Hemolytic toxicity, cell proliferation, and morphological assessment were performed to evaluate the biocompatibility. Alkaline phosphatase (ALP) level, mineralization, and qRT-PCR were measured to evaluate the osteointegration. During the manufacturing of ß-TCP, no evident impurity substance and hemolytic toxicity was found. Cells on ß-TCP had good morphologies, and their proliferation capability was similar to Ti6Al4V, which was higher than the other materials. Cells on ß-TCP had higher ALP levels than PEEK. The degree of mineralization was significantly higher on ß-TCP. The expression of osteogenesis-related genes on ß-TCP was similar to Ti6Al4V and higher than the other materials. In this study, the ß-TCP produced by stereolithography had no toxicity, high accuracy, and excellent osteointegration capability, thus resulting as a good choice for bone implants.

Panax notoginseng saponins prevent colitis-associated colorectal cancer via inhibition IDO1 mediated immune regulation.

Colorectal cancer (CRC) is the third most lethal cancer and leading cause of cancer mortality worldwide. A key driver of CRC development is colon inflammatory responses especially in patients with inflammatory bowl disease (IBD). It has been proved that Panax notoginseng saponins (PNS) have anti-inflammatory, anti-oxidant and anti-tumor effects. The chemopreventive and immunomodulatory functions of PNS on colitis-associated colorectal cancer (CAC) have not been evaluated.This present study was designed to study the potential protective effects of PNS on AOM/DSS-induced CAC mice to explore the possible mechanism of PNS against CAC. Our study showed that PNS significantly alleviated colitis severity and prevented the occurrence of CAC. Functional assays revealed that PNS relieved immunosuppression of Treg cells in the CAC microenvironment by inhibiting the expression of IDO1 mediated directly by signal transducer and activator of transcription 1 (STAT1) rather than phosphorylated STAT1. Ultimately, Rh1, one of the PNS metabolites, exhibited the best inhibitory effect on IDO1 enzyme activity. Our study showed that PNS exerted significant chemopreventive function and immunomodulatory properties on CAC. It could reduce macrophages accumulation and Treg cells differentiation to reshape the immune microenvironment of CAC. These findings provided a promising approach for CAC intervention.

miR-672-3p Promotes Functional Recovery in Rats with Contusive Spinal Cord Injury by Inhibiting Ferroptosis Suppressor Protein 1.

Aberrantly expressed microRNAs (miRNAs) after spinal cord injury (SCI) participate in diverse biological pathways and processes, including apoptosis, inflammation, oxidative stress responses, peroxidation, and ferroptosis. This study was aimed at exploring the mechanisms underlying miRNA-mediated ferroptosis in an SCI rat model. In the present study, a T10 weight-dropping SCI model was established and miRNA profiling was used to detect miRNA expression profiles post-SCI. Basso-Beattie-Bresnahan scores and inclined plane test, hematoxylin and eosin (HE) and Nissl staining, immunohistochemistry and immunofluorescence, western blotting, cell viability, and Annexin V/7-aminoactinomycin D (7-AAD) assays were used to evaluate locomotor activity, histological changes in the injured spinal cords, neuronal ferroptosis, ferroptosis suppressor protein 1 (FSP1) expression, and cell death, respectively. It was observed that many miRNAs were differentially expressed after SCI, and miR-672-3p, which increased significantly, was selected after cross-referencing with predicted target miRNAs. The luciferase reporter assay demonstrated that miR-672-3p downregulated FSP1, a glutathione-independent ferroptosis suppressor, by binding to its 3' untranslated region. Oxygen and glucose deprivation- (OGD-) treated PC12 and AGE1.HN cells were treated with miR-672-3p mimics or inhibitors in vitro. The effect of miR-672-3p mimics or inhibitor on OGD-PC12/AGE1.HN ferroptosis was evaluated by flow cytometry, immunohistochemistry, immunofluorescence, and western blotting. The miR-672-3p mimics promoted ferroptosis after SCI, whereas the miR-672-3p inhibitor inhibited this process. Rats with SCI treated with miR-672-3p mimics or inhibitor showed similar results in vivo. Furthermore, the ferroptosis-related changes caused by SCI or miR-672-3p were reversed by overexpression of FSP1 lentivirus in vivo and in vitro. These results indicated that sh-miR-672-3p exerted a neural restoration effect in vivo and in vitro by inhibiting ferroptosis via the FSP1 pathway.

[miRNA-181a-5p inhibits proliferation and migration of osteosarcoma cell line HOS by targeting HOXB4].

OBJECTIVE: To study the effects and mechanisms of miR-181a-5p on the proliferation, cycle and migration of HOS osteosarcoma cells. METHODS: Real-time quantitative PCR was used to detect the expression of miR-181a-5p and HOXB4 in osteoblast hFOB1.19 cell line and osteosarcoma cell lines (HOS, U2OS, MG63). miR-181a-5p mimics and miR-181a-5p inhibitors were respectively transfected into HOS cells by Lipofectamine 2000, and miR NC group was set as control group. CCK-8 method was used to detect the change in cell proliferation. Flow cytometry was used to detect the changes in cell cycles. Wound healing experiments and Transwell migration experiments were used to detect the changes in cell migration ability. The target gene of miR-181a-5p was predicted by Targetscan website and validated by Dual-luciferase reporter gene system and Western blot. RESULTS: Compared with osteoblast hFOB1.19, miR-181a-5p was low expressed in osteosarcoma cells HOS, U2OS, and MG63(P<0.05), while HOXB4 was high expressed in osteosarcoma cells HOS, U2OS, and MG63(P<0.05). Compared with the miR NC group, over expression of miR-181a-5p inhibited the proliferation and migration of osteosarcoma HOS cells, and the number of cells in S phase decreased(P<0.05). However, knockdown miR-181a-5p promoted the proliferation and migration of osteosarcoma HOS cells, the cells in S phase increased(P<0.05). Bioinformatics prediction and Dual-luciferase reporter gene system validate HOXB4 as a downstream target gene of miR-181a-5p(P<0.05). Western blot showed that miR-181a-5p over expression or knockdown significantly down-regulated or up-regulated HOXB4 expressions in the HOS cells respectively(P<0.05). CONCLUSION: miR-181a-5p is down expressed in osteosarcoma cells, and over-expression miR-181a-5p inhibits the proliferation, cell cycle and migration ability of osteosarcoma cells by targeting HOXB4.

Macrophage Extracellular Traps Exacerbate Secondary Spinal Cord Injury by Modulating Macrophage/Microglia Polarization via LL37/P2X7R/NF-κB Signaling Pathway.

Persistent inflammation in the secondary spinal cord injury (SCI) is an important reason for the failure of nerve repair, which is partly due to the continuous activation of local M1-like macrophage/microglia. It is reported that extracellular trap (ET) has been a new way of cell death, which can be released by macrophages and named macrophage extracellular trap (Met). Furthermore, it exists widely in the pathophysiological process of many diseases, but it has been rarely studied in the field of SCI. In this study, we constructed a spinal cord contusion model and assessed the function outcome of SCI rats. We used immunofluorescence, flow cytometry, and transmission electron microscope (TEM) to demonstrate the existence of Mets. Besides, some related experiments had also been employed to explore the relationship between Mets and M1 polarization of macrophage/microglia. We also performed Co-IP and Western blotting to reveal a new extracellular proinflammatory signal pathway. Finally, we made a linear regression analysis between the concentrations of specific markers of Mets in human serum and ASIA scores. Briefly, our results suggested that macrophages infiltrated in SCI area could induce macrophage/microglia to differentiate into M1-like cells by releasing Mets, which may be achieved partly through LL37-P2X37-NF-κB signal pathway. However, limiting Mets could effectively inhibit M1 polarization and promote function recovery. In addition, the concentrations of Met related proteins in human serum showed high correlation with ASIA scores and could be applied to reflect the severity of SCI. In conclusion, Mets may be a new target for SCI therapy and a promising index for SCI assessment.

[N2O Production Pathways in Partial Nitrification Based on Isotope Technology].

Batch experiments were conducted under normal temperature conditions to study the generation of N2O in the partial nitrification process under different dissolved oxygen concentrations and their production pathways. When dissolved oxygen was 0.5, 1.5, and 2.5 mg·L-1, the proportion of N2O released into the total nitrogen input was 4.35%, 3.27%, and 2.63%, respectively. With increase dissolved oxygen, the proportion of N2O released to total influent nitrogen was reduced. Isotope measurements showed that when dissolved oxygen was 0.5 mg·L-1, only denitrification by ammonia-oxidizing bacteria (AOB) produced N2O. However, when dissolved oxygen increased to 1.5 mg·L-1, the activity of nitrifying bacteria increased, and 4.52% of N2O was generated through a hydroxylamine oxidation process, whereas the N2O generated by AOB denitrification accounted for 95.48%. When dissolved oxygen continuously increased to 2.5 mg·L-1, the proportion of N2O produced by hydroxylamine oxidation increased to 9.11%, and the N2O generated by AOB denitrification accounted for 90.89%. The change in dissolved oxygen concentration affects the N2O production pathway in the short-cut nitrification process, and avoiding excessive NO2--N accumulation can reduce the production of N2O.

Removal of Pb2+, Hg2+, and Cu2+ by Chain-Like Fe3O4@SiO2@Chitosan Magnetic Nanoparticles.

In this paper, the chain-like core-shell structure Fe3O4@SiO2@Chitosan composite nanoparticles were synthesized by a two-step coating and following crosslinking glutaraldehyde on chitosan shell. The composite particles showed nearly monodisperse 105 sized particles with a core diameter of 80 nm and chitosan shell thickness of 12 nm. The synthesis conditions of the product were studied, and the morphology and properties of the composite nanoparticles were characterized by IR, XRD, TEM, SEM, EDS and VSM. The adsorption properties of Hg2+, Pb2+ or Cu2+ ions on Fe3O4, Fe3O4@SiO2 and the composite particles were in detail studied using the colorimetric method based on forming colored mercuric dithizone, rhodamine-Pb2+ complex and DDTC-Cu(2+) complex. The results showed, adsorption isotherm, kinetics and separation coefficient of heavy metal ions on these three magnetic nanoparticles were concerned with pH, metal ions' electronic configuration, silica coating and chitosan shell respectively. In addition, the recycle efficiency was also studied. The findings demonstrated that Fe3O4@SiO2@Chitosan composite nanoparticles have great application value in the adsorption and separation of heavy metal ions.