Removal of microplastics via drinking water treatment: Current knowledge and future directions

The occurrence of microplastics in drinking water systems has increasingly become a major environmental challenge. Although the potential impacts of microplastics in drinking water on humans are not yet fully understood, microplastics attract the public health concern when they are consumed by humans through drinking water systems. Current drinking water treatment plants constitute an obstacle to the entry of microplastics from raw water into daily drinking water. Therefore, understanding the behaviors of drinking water treatment process and the fates of microplastics in drinking water treatment plants are very important. We systematically reviewed the available knowledge on the global existence of microplastics in raw water, treated water and tap water in this paper. This will offer a new perspective for the threat of microplastics in drinking water to human health and help to formulate effective strategies for microplastic monitoring. The existing knowledge of microplastic removal by different treatment processes was also thoroughly discussed. Additionally, the potential challenges of microplastic removal from treatment processes and remediation strategies of microplastics in drinking water were also put forward. The relationship between the properties and behavior of microplastics during different treatment processes is suggested to explore in the future.

In Situ Grown Single-Atom Cobalt on Polymeric Carbon Nitride with Bidentate Ligand for Efficient Photocatalytic Degradation of Refractory Antibiotics

Semiconductor photocatalysis is a promising technology to tackle refractory antibiotics contamination in water. Herein, a facile in situ growth strategy is developed to implant single-atom cobalt in polymeric carbon nitride (pCN) via the bidentate ligand for efficient photocatalytic degradation of oxytetracycline (OTC). The atomic characterizations indicate that single-atom cobalt is successfully anchored on pCN by covalently forming the CoO bond and CoN bond, which will strengthen the interaction between single-atom cobalt and pCN. This single-atom cobalt can efficiently expand optical absorption, increase electron density, facilitate charge separation and transfer, and promote OTC degradation. As the optimal sample, Co(1.28%)pCN presents an outstanding apparent rate constant for OTC degradation (0.038 min^-1 ) under visible light irradiation, which is about 3.7 times than that of the pristine pCN. The electron spin resonance (ESR) tests and reactive species trapping experiments demonstrate that the ¹ O₂ , h⁺ , •O₂^- , and •OH are responsible for OTC degradation. This work develops a new way to construct single-atom-modified pCN and provides a green and highly efficient strategy for refractory antibiotics removal.

Inhibition of BMP3 increases the inflammatory response of fibroblast-like synoviocytes in rheumatoid arthritis

Rheumatoid arthritis (RA) is a persistent autoimmune disease. Fibroblast-like synoviocytes (FLS) are a key component of invasive pannus and a pathogenetic mechanism in RA. Expression of bone morphogenetic protein 3 (BMP3) mRNA is reportedly decreased in the arthritic synovium. We previously showed that BMP3 expression is significantly downregulated in the synovial tissues of RA patients and models of adjuvant-induced arthritis (AIA). In the present study, we explored the association between BMP3 and FLS migration and secretion of proinflammatory factors in RA. We found that inhibition of BMP3 expression using BMP3 siRNA increased the proinflammatory chemokines and migration of FLS stimulated with TNF-α. Inhibition of BMP3 expression also increased expression of IL-6, IL-1β, IL-17A, CCL-2, CCL-3, VCAM-1, MMP-3, and MMP-9, but not TIMP-1, in AIA and RA FLS. Correspondingly, induction of BMP3 overexpression through intra-articular injection of ad-BMP3 diminished arthritis severity in AIA rats. We also found that BMP3 may inhibit activation of TGF-β1/Smad signaling. These data indicate that BMP3 may suppress the proliferation and migration of FLS via the TGF-β1/Smad signaling pathway.

Influence of multi-walled carbon nanotubes on the microbial biomass, enzyme activity, and bacterial community structure in 2,4-dichlorophenol-contaminated sediment

The rise in manufacture and use of carbon nanotubes has aroused the concern about their potential risks associated with coexisting pollutants in the aquatic environment. 2,4-dichlorophenol (2,4-DCP), with a high toxicity to many aquatic organisms, is a widespread pollutant resulting from the extensive use of pesticides and preservatives. In this article, the adsorption of 2,4-DCP by riverine sediment and the responses of sediment microbial community to 2,4-DCP were studied in the presence of multi-walled carbon nanotubes (MWCNTs). Adding MWCNTs significantly increased the adsorption amount of sediment for 2,4-DCP from 0.541 to 1.44 mg/g as the MWCNT concentration increased from 0 to 15 mg/g. The responses of sediment microbial community were determined after one-month exposure to MWCNTs at different concentrations (0.05, 0.5, 5, and 50 mg/g). The microbial biomass carbon in the sediment contaminated with 2,4-DCP increased in the presence of 5 mg/g of MWCNTs (from 0.06 to 0.11 mg/g), but not significantly changed at other MWCNT concentrations. For the sediments contaminated with 2,4-DCP, the presence of MWCNTs made no difference to urease activity, while the dehydrogenase activity slightly increased with the addition of 5 mg/g of MWCNTs and decreased in the presence of 50 mg/g of MWCNTs. The changes of sediment bacterial communities were further determined by 16S rRNA gene sequencing. Based on the weighted UniFrac distance between communities, the clustering analysis suggested that the contamination of 2,4-DCP affected the bacterial community structure in a greater degree than that caused by MWCNTs at relatively low concentrations (≤5 mg/g). Bacteroidetes, Planctomycetes, and Nitrospirae were feature bacterial phyla to reflect the effects of MWCNTs and 2,4-DCP on sediment bacterial community. These results may contribute to the understanding of microbial community response to co-exposure of MWCNTs and 2,4-DCP and the assessment of associated ecological risks.

Distorted polymeric carbon nitride via carriers transfer bridges with superior photocatalytic activity for organic pollutants oxidation and hydrogen production under visible light

Polymeric carbon nitride (PCN) has become the most promising metal-free photocatalysts but its activity is low. Molecule doping of PCN has been proved to be an effective strategy to achieve high photocatalytic performance. Herein, we report a bottom-up method to synthesize modified PCN, which includes 2,5-dibromopyrazine doping, thermal-induced exfoliation and condensation/polymerization. The incorporation of electron-deficiency 2,5-dibromopyrazine into the PCN framework can effectively tune the electronic structures and improve the charge-carrier separation. In addition, the incorporation of 2,5-dibromopyrazine induced significant structural changes from planar symmetric to distortion. The optimized pyrazine doped PCN showed a reaction rate enhancement of 4-fold for the degradation of sulfamethazine compared to that of conventional urea-based PCN. Further reactive species and degradation intermediate detection studies, indicated that O₂^- was generated during the photocatalytic process, which could lead to the decomposition, and finally mineralization of sulfamethazine. 2,5-Dibromopyrazine doped PCN also leads to a 6.3-fold improvement in H₂ generation with the visible light. Especially, phytotoxicity experiments showed that the toxicity of sulfamethazine after degradation is greatly reduced, and the as-prepared photocatalyst is environmentally friendly.

A stochasticlocation privacy protection scheme for edge computing

Location-based Service has become the fastest growing activity related service that people use in their daily life due to the boom of location-aware mobile devices. In edge computing along with the benefits brought by LBS, privacy preservation becomes a more challenging issue because of the nature of the paradigm, in which peers may cooperate with each other to collect and analyze user's location data. To avoid potential information leakage and usage, user's exact location should not be exposed to the edge node. In this paper, we propose a stochastic location privacy protection scheme for edge computing, in which the geographical distribution of surrounding users is obtained by analyzing proposed long-term density map and short-term density map. The cloaking scheme transfers user's exact location to a cloaked location to satisfy predefined probability of having k-users in that area. Our scheme does not reveal any exact location information, thus it is practicable for the real scenario when edge computing is honest but curious. Extensive experimental results are conducted to verify the efficiency and effectiveness of our method. By varying the privacy protection requirements, the corresponding performance have been examined and discussed.

Responses of enzymatic activity and microbial communities to biochar/compost amendment in sulfamethoxazole polluted wetland soil

Biochar and compost, two common amendments, were rarely conducted to investigate their combined influence on enzymatic activities and microbial communities in organic-polluted wetlands. This article described the effects of biochar/compost on degradation efficiency of sulfamethoxazole (SMX) and ecosystem responses in polluted wetland soil during the whole remediation process. 1% biochar (SB1) increased degradation efficiency of SMX by 0.067% ascribed to the increase of dehydrogenase and urease. 5% biochar (SB5) decreased degradation efficiency by 0.206% due to the decrease of enzymes especially for dehydrogenase. 2% compost (SC2), 1% biochar & 2% compost (SBC3), both 10% compost (SC10) and 5% biochar & 10% compost (SBC15) enhanced degradation efficiency by 0.033%, 0.015% and 0.222%, respectively, due to the increase of enzymes and biomass. The degradation efficiency was positively related to biomass and enzymatic activities. High-throughput sequencing demonstrated that HCGs (SB5, SC10, SBC15) improved the bacterial diversities but reduced richness through introducing more exogenous predominance strains and annihilated several inferior strains, while LCGs (SB1, SC2, SBC3) exhibited lower diversities but higher richness through enhanced the RAs of autochthonal preponderant species and maintained some inferior species. Additionally, HCGs raised the RAs of amino and lipid metabolism gene but lowered those of carbohydrate compared with LCGs.

[Comparison on efficacy and safety of different bridging anticoagulation therapies in patients undergoing mechanical heart valve replacement surgery]

Objective: To evaluate the efficacy and safety of different bridging anticoagulant therapies in patients undergoing mechanical heart valve replacement (MHVR) surgery. Methods: Consecutive patients undergoing MHVR surgery from January 2018 to December 2018 in First Hospital of Lanzhou University were prospectively enrolled in this study. Patients were divided into unfractionated heparin (UFH) group and low molecular weight heparin (LMWH) group according to the postoperative bridging anticoagulation methods. Preoperative clinical data and postoperative related time and cost parameters, including drainage time, duration of stay in intensive care unit (ICU), postoperative time (interval from end of operation to discharge) and INR stabilization time (interval from start of bridge anticoagulation to INR value reaching the standard for 2 consecutive days) of all enrolled patients were collected, and all patients were followed up for 4 weeks and thromboembolic or bleeding events were analyzed. Multivariate logistic regression was used to determine the independent prognostic factors of thromboembolic or bleeding events after MHVR receiving various bridging anticoagulant therapies. Results: A total of 217 patients were included in the study, including 120 patients in the UFH group and 97 patients in the LMWH group. Stroke occurred in two patients in the UFH group, while no stroke event occurred in the LMWH group. The incidence of bleeding events was significantly higher (9.28%(9/97) vs. 1.67%(2/120), P=0.02), while the drainage time, duration of stay in ICU, postoperative time, INR stabilization time were all significantly shorter in LMWH group than in UFH group (all P<0.05). Multivariate logistic regression analysis showed that bridging anticoagulation therapies (OR=0.18, 95%CI 0.04-0.86, P=0.03), fibrinogen level (OR=1.99, 95%CI 1.16-3.41, P=0.01) and creatinine level (OR=1.05, 95%CI 1.01-1.08, P=0.04) were independent prognostic factors for bleeding events. Conclusion: LMWH use is associated with increased risk of bleeding events, but can significantly reduce the drainage time, duration of stay in ICU, postoperative time, INR stabilization time in patients post MHVR surgery.

MiR-143 regulates proliferation and apoptosis of myelocytic leukemia cell HL-60 via modulating ERK1

OBJECTIVE

Extracellular signal-regulated kinase (ERK)/mitogen activated protein kinase (MAPK) signaling pathway is widely involved in cell proliferation and invasion regulation. Enhanced expression or function of ERK1 is important for leukemia. Abnormal down-regulation of microRNA (miR)-143 is correlated with leukemia pathogenesis, indicating possible tumor-suppressing role. Bioinformatics analysis showed the existence of complementary binding sites between miR-143 and ERK1. This study aims to investigate whether the miR-143 plays a role in mediating ERK1 expression and proliferation and apoptosis of leukemia cells.

PATIENTS AND METHODS

Dual luciferase reporter gene assay confirmed targeted regulation between miR-143 and ERK1. Quantitative RT-PCR (qRT-PCR) was used to measure and compare the peripheral miR-143 and ERK1 expression between healthy and acute promyelocytic leukemia (APL) patients to analyze the effect of miR-143 and MEK1 on survival and prognosis. Cultured HL-60 cells were treated with miR-143 mimic or small interfering RNA (siRNA)-ERK1, followed by qRT-PCR to measure miR-143 expression. Western blot quantified expression of ERK1 and p-ERK1, flow cytometry measured apoptosis, and EdU staining measured proliferation.

RESULTS

MiR-143 targeted and modulated ERK1. APL patients presented lower miR-143 and higher ERK1 in peripheral blood. Those with miR-143 down-regulation displayed worse prognosis than those with high miR-143 expression (χ2 = 5.198, p = 0.039). Patients with ERK1 mRNA low-expression presented better prognosis than those a having higher expression (Log-rank test, χ2 = 5.873, p = 0.028). Transfection of miR-143 mimic or siRNA-ERK1 remarkably suppressed ERK1 and p-ERK1 expression in HL-60 cells, inhibited cell proliferation and induced cell apoptosis.

CONCLUSIONS

MiR-143 down-regulation and ERK1 up-regulation are correlated with APL pathogenesis. Their expression level affected patient's prognosis. MiR-143 targeted and inhibited ERK1 expression, weakened proliferation potency of HL-60 cells, and induced apoptosis.

Can biotechnology strategies effectively manage environmental (micro)plastics?

With the convenience of plastic products to daily life, the negative sides of the plastic-age have gradually emerged. Like other pollutants, complex environmental factors result in the ubiquitous presence of (micro)plastics worldwide, raising potential risks to the ecological systems. However, due to the limitation of traditional technologies in treating these materials, new strategies should be developed. More recently, researchers have showed that biotechnology strategies could be promising approaches to effectively manage and control (micro)plastics in the environment, because some microorganisms have been confirmed to be successfully capable of degrading (micro)plastics. Nevertheless, the biotechnology is still in its infancy, and most studies are carried out under laboratory conditions. The biodegradation process is affected by many factors: microorganism species, carbon sources, material types and sizes. Problematically, (micro)plastics are highly stable in the environment, which are difficult to be used as carbon sources for microorganisms. Biodegradation of (micro)plastics requires appropriate conditions, which are not always feasible in field conditions. As such, although biotechnology strategies might be a promising approach to remove environmental (micro)plastics, we believe it is not now at least.

Tuning Electron Density Endows Fe1-xCoxP with Exceptional Capability of Electrooxidation of Organic Pollutants

The good performance of base metal catalysts for the electrooxidation of organic pollutants has attracted great attention. However, base metal phosphides for electrooxidation are seldom studied owing to the sluggish water adsorption and dissociation dynamics, which will hinder the production of the sorbed hydroxyl radicals (M(^•OH)) and thus inhibit the electrooxidation of organic pollutants. Herein, we proposed a universal strategy to improve the electrooxidation capability of metal phosphides by modulating the surface electron densities. The electron interactions between cobalt (Co) and phosphorus (P) are modulated after iron doping, resulting in more positively charged Co and more negatively charged P, which can promote the adsorption and activation of water molecules and produce large quantities of M(^•OH). Meanwhile, the experimental results show that the iron-modulated Fe_0.53Co_0.47P nanosheet arrays exhibit higher removal efficiency of tetracycline than the boron-doped diamond and Pt anode at low current intensity. Based on experimental results and density functional theory + U calculations (DFT + U), it is found that Fe_0.53Co_0.47P has lower barrier (0.45 eV) to form the sorbed hydroxyl radicals (M(^•OH)) and higher overpotential to produce O₂ than its counterparts, suggesting that Fe_0.53Co_0.47P can produce more M(^•OH) instead of O₂. The above results highlighted the feasibility of these base metal phosphides for electrooxidation for advanced water purification.

Improved display of abdominal contrast-enhanced MRA using gadobutrol: comparison with Gd-DTPA

AIM

To qualitatively and quantitatively compare gadobutrol with gadopentetate dimeglumine (Gd-DTPA) in abdominal contrast-enhanced magnetic resonance angiography (CE-MRA) and contrast-enhanced magnetic resonance imaging (CE-MRI) during one-stop imaging.

MATERIALS AND METHODS

This prospective, blinded, multicentre, intra-individual comparison study was approved by the institutional review board. All patients underwent gadobutrol- and Gd-DTPA-enhanced MRA and MRI. Qualitative analysis for vessels was performed using a three-point scale while quantity analysis was performed by signal-to-noise ratio (SNR). Visceral organs enhancements were also analysed. A Wilcoxon matched-pair signed-rank test was used to evaluate the quality and quantity results.

RESULTS

One hundred and twelve patients were enrolled. Quality analyses results for large vessels and small vessels of gadobutrol and Gd-DTPA were 18.38±1.51 and 6.76±1.58 and 17.87±1.84 and 6.09±1.55, respectively. Wilcoxon signed-rank tests revealed gadobutrol was significantly superior to Gd-DTPA (p=0.036) for small vessels. For large vessel quantity analysis, gadobutrol demonstrated significantly higher signal-to-noise ratios (SNR; p=0.041) than Gd-DTPA, with mean values of 948.156±349.731 and 838.925±248.197. There was no statistically significant in enhancement of liver, spleen, and renal tissue during gadobutrol- and Gd-DTPA-enhanced imaging (p>0.05). One patient reported an adverse event. Dizziness and vomiting occurred after injection of Gd-DTPA.

CONCLUSIONS

The present study demonstrates gadobutrol-enhanced MRA was superior to that of Gd-DTPA without statistical significance in visceral organ enhancement. It indicates gadobutrol may be more suitable for abdominal one-stop imaging for CE-MRA and CE-MRI by improving depiction of vessels in MRA images.

Heterogeneous Fenton-like catalyst for treatment of rhamnolipid-solubilized hexadecane wastewater

The treatment of wastewater containing hydrophobic organic pollutants solubilized by surfactants is of great environmental importance. In this work, the removal of rhamnolipid-solubilized hexadecane via a salicylic acid-methanol-acetone modified steel converter slag (SMA-SCS) catalyzed Fenton-like process was studied. First, we investigated the adsorption of rhamnolipid and hexadecane onto SCS and SMA-modified SCS. Compared to that of SCS, SMA-SCS exhibited better adsorption performance with maximum adsorption capacities of 0.23 and 0.28 mg/g for hexadecane and rhamnolipid, respectively. Degradation experiments showed that hexadecane was more readily degraded by the Fenton-like process than rhamnolipid. Up to 81.1% of hexadecane removal was achieved over 20 g/L of SMA-SCS within 24 h, whereas only 36% of rhamnolipid was degraded. On the other hand, the results indicated that increased rhamnolipid concentration had a negative effect on the degradation of hexadecane. During the oxidation reaction, the pH value of solution remained between 6.0 and 6.72. All these results demonstrated that the SMA-SCS/H₂O₂ Fenton-like process could be a cost-effective and promising approach for the treatment of surfactant-solubilized hydrophobic organic compounds.

The performance of UiO-66-NH2/graphene oxide (GO) composite membrane for removal of differently charged mixed dyes

The dye wastewater treatment by membrane separation technology has obtained extensive attention in recent years. Nevertheless, it was rare for research on the removal of differently charged mixed dyes. In this study, several UiO-66-NH₂ composite membranes were prepared and optimization experiments were conducted. The performance of composite membranes were evaluated by the removal of cationic (Methylene blue, MB), neutral (Rhodamine B, RB), and anionic (Congo red, CR) dyes. The optimization results demonstrated that the UiO-66-NH₂/graphene oxide (UNG) composite membrane (PUF/PDA/UNG) which was loaded on polyurethane foam modified with polydopamine (PUF/PDA) had the best properties. In filtration experiments, the solution pH exhibited greater effect on the removal efficiency of MB and CR than RB. When NaCl, KCl, CaCl₂ and Na₂SO₄ coexisted in the dye solution, the removal efficiency of MB by PUF/PDA/UNG membrane were 96.62%, 98.17%, 86.39% and 99.34% respectively. The presence of humic acid showed slight inhibitory effect on the removal of MB by PUF/PDA/UNG membrane (71.93%). The experimental results for mixed dyes filtration showed that PUF/PDA/UNG membrane could effectively remove MB, RB and CR in binary (i.e., MB/RB and RB/CR) and ternary (i.e., MB/RB/CR) systems through secondary filtration. And PUF/PDA/UNG membrane could remove MB and CR simultaneously through one-time filtration in MB/CR binary system. The removal mechanism was mainly attributed to the aggregation of mixed dyes, electrostatic interaction between dye molecules and the membrane surface, and hydrogen bonding. All results suggested that the as-prepared PUF/PDA/UNG membrane have great potential in practical treatment of dye wastewater.

Dietary leucine supplementation improves intestinal health of mice through intestinal SIgA secretion

AIMS

Leucine supplementation promotes intestinal health, but the mechanism is largely unknown. This study aimed to elucidate the mechanisms underlying the beneficial effects of leucine on intestinal homeostasis.

METHODS AND RESULTS

Female ICR mice (6-week-old) were randomly assigned into three groups: (i) mice received a basal diet; (ii) mice received a dietary 0·5% crystalline l-leucine supplementation; and (iii) mice received a dietary 1·0% crystalline l-leucine supplementation. Our results showed that leucine supplementation stimulated the secretion of SIgA in mice ileum and expression of cytokines related to SIgA production. Moreover, leucine supplementation improved the expression of mTOR and p70S6K1 expression. Further study showed that leucine supplementation markedly decreased microbiota richness and induced a shift in the Firmicutes : Bacteroidetes ratio in favour of Firmicutes.

CONCLUSIONS

Therefore, our data suggested that leucine supplementation could enhance intestinal health through the regulation of mTOR pathway and promoting SIgA secretion in the mouse intestine, which might be associated with intestinal microbiota.

SIGNIFICANCE AND IMPACT OF THE STUDY

The present study found that dietary leucine supplementation of mice could improve intestinal health by enhancing intestinal SIgA secretion via a nonexclusive mechanism, which might include T cell-dependent pathway, T cell-independent pathway and gut microbiota.

Targeted inhibition of β-catenin by miR-320 and decreased MMP-13 expression in suppressing chondrocyte collagen degradation

OBJECTIVE

Wnt/β-catenin pathway plays a critical role in modulating embryonic development, cell growth, and differentiation. The over-expression of β-catenin activates this pathway and up-regulates expression of matrix metalloproteinase-13 (MMP-13), and promotes matrix degradation and occurrence of osteoarthritis (OA). This study aims to explore the effect of miR-320 expression in OA chondrocyte and underlying mechanisms.

PATIENTS AND METHODS

Chondrocyte tissues from OA patients and normal individuals were collected for the detection of expression levels of miR-320, β-catenin, MMP-13, and alpha-1 chain of type II collagen (COL2A1). Dual luciferase reporter assay was performed to test targeted regulation between miR-320 and β-catenin. IL-1β was used to simulate in vitro cultured chondrocytes, which were transfected with miR-320 mimic and/or si-β-catenin, followed by quantification of miR-320, β-catenin, MMP-13, and COL2A1.

RESULTS

In chondrocytes of OA patients, expression of microRNA (miR)-320 is decreased. Bioinformatics analysis revealed complementary binding sites between miR-320 and β-catenin. Compared to control group, increasing levels of β-catenin and MMP-13 expression with reduction of miR-320 and COL2A1 expressions were observed in OA chondrocytes. Transfection of miR-320 mimic and/or si-β-catenin depressed expression of β-catenin and MMP-13 inside chondrocytes, accompanied with elevation of COL2A1 expression.

CONCLUSIONS

MiR-320 expression in OA chondrocyte is decreased, accompanied with up regulation of β-catenin and MMP-13. MiR-320 can inhibit β-catenin and MMP-13 expressions, elevates COL2A1 expression, which provides novel insights for the treatment of osteoarthritis.

[Prediction model for survival in patients with biliary tract cancer: a development and validation study]

Objective: The aim of the present study was to investigate the survival rate and its prognostic factors for patients with biliary tract cancer, and then a prognostic risk prediction model was constructed to predict the survival probability of patients. Methods: A total of 14 005 patients with biliary tract cancer (including gallbladder cancer, extrahepatic bile duct cancer, and ampulla of Vater cancer), who were diagnosed between 2010 and 2015 in the US National Cancer Institute Surveillance, Epidemiology, and End Results Program (SEER) were included in the development cohort. The prognostic risk factors of biliary tract cancer were investigated using multivariate Cox regression models. The predictive nomograms were then constructed to predict the overall survival probability of 1, 3, and 5 years, and the predictive discrimination and calibration ability of the nomograms were further evaluated. Meanwhile, 11 953 patients who were diagnosed during 2004 to 2009 from SEER Program were then selected to validate the external predictive accuracy of the prediction models. Results: The 1, 3 and 5-year cumulative survival rates of patients with biliary tract cancer were 41.9%, 20.4% and 15.3%, respectively, in the development cohort. Age greater than 50 years, African Americans and Native Americans and Alaska Natives, higher T, N and M stage and poor histological differentiation grade were risk factors for death, while married status, Asia-Pacific Islanders, insured status and surgery on primary site were protective factors. Gender was not significantly associated with the overall survival. The C statistic of the prediction model was 0.73 (95%CI: 0.72-0.74), and the calibration curve showed that the interaction curves of predictive and actual survival rates of 1, 3 and 5 years were close to the 45 degree diagonal. Results in the validation cohort were similar with those in the construction cohort, with a C statistic of 0.70 (95%CI: 0.69-0.72), indicating high external applicability of the prediction model. Findings from gallbladder cancer, extrahepatic bile duct cancer, and ampulla of Vater cancer are in consistent with the overall biliary tract cancer. Conclusions: The survival rate of patients with biliary tract cancer is relatively poor, and the survival prediction model based on prognostic factors has high prediction accuracy. In the future, this prognostic prediction model could be applied to clinical practice to guide individualized treatment for patients with biliary tract cancer.

Cell migration and osteo/odontogenesis stimulation of iRoot FS as a potential apical barrier material in apexification

AIM

To investigate the in vitro biological effects of a nanoparticle bioceramic material, iRoot Fast Set root repair material (iRoot FS), on the proliferation, migration and osteo/odontogenic differentiation of human stem cells from the apical papilla (hSCAP), and to further explore the mechanism involved in osteo/odontogenic induction of iRoot FS.

METHODOLOGY

hSCAP were isolated and characterized in vitro. iRoot FS conditioned medium were prepared and used to treat hSCAP, while using mineral trioxide aggregate (MTA) conditioned medium as the positive control and regular medium as the negative control. MTT assay and BrdU labelling assay were performed to determine cell proliferation. Wound healing assay and transwell assay were conducted to evaluate cell migration. The osteo/odontogenic differentiation of hSCAP was evaluated by qPCR, Western blot and Alizarin red S staining. Wnt inhibitor was used for downregulating the expression level of β-catenin of hSCAP.

RESULTS

The cell proliferation of hSACP in the iRoot FS group was not significantly different compared with the control groups. The cell migration of hSCAP in the iRoot FS group was significantly increased than the MTA and negative control groups (P < 0.01). The expression levels of osteo/odontogenic markers and mineralization nodule formation of hSCAP in the iRoot FS group were significantly elevated (P < 0.01). Furthermore, iRoot FS enhanced the osteo/odontogenic differentiation of hSCAP by activating Wnt/β-catenin signalling.

CONCLUSIONS

iRoot FS promoted the cell migration of hSCAP and enhanced their oseto/odontogenesis potential via the Wnt/β-catenin pathway without cytotoxicity. iRoot FS had satisfactory biological properties and has potential to be used as an apical barrier in apexification or as a coronal sealing material in regenerative endodontic treatment.

Free fatty acids mediates human umbilical vein endothelial cells inflammation through toll-like receptor-4

OBJECTIVE

To investigate the role of Toll-like receptor-4 (TLR4) in the free fatty acids (FFAs) induced human umbilical vein endothelial cells (HUVECs) inflammation and to explore the underlying mechanisms.

MATERIALS AND METHODS

HUVECs and HEK293 cell lines were obtained from Shanghai Type Culture Collection. Cell counting kit-8 (CCK8) and flow cytometry (FCM) were performed to examine the cell viability and apoptosis rate of HUVECs induced by FFAs treatments with or without infection of toll-like receptor-4 interference (TLR4i) adenovirus. Enzyme-linked immunosorbent assay (ELISA) was performed to evaluate the inflammatory cytokines release. Quantitative polymerase chain reaction (qPCR) and Western Blot (WB) were used to test the molecular mechanisms of inflammation.

RESULTS

FFAs induced inflammatory responses in HUVECs via modulating the TLR4 receptor complex. TLR4i adenovirus interference increased cell viability and decreased cell apoptosis rate. FFAs treatments significantly increased the expressions of inflammatory cytokines interleukin-6 (IL-6), interleukin-8 (IL-8), C-C motif chemokine ligand 5 (CCL5) and CXC chemokine ligand 10 (CXCL10), while TLR4i adenovirus interference significantly reduced these cytokines levels. TLR4-mediated myeloid differential protein-88 (MyD88) expression activating the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and inhabiting kappa B kinase-beta (IKK-β). TLR4i adenovirus interference decreased the expressions of these genes at both mRNA level and protein level.

CONCLUSIONS

TLR4 mediates FFAs induced inflammatory responses in HUVECs. TLR4 interference in HUVECs significantly reduces the inflammatory cytokines expression, decreases the cell apoptosis rate and increases cell viability.

MicroRNA-338 inhibits proliferation, migration, and invasion of gastric cancer cells by the Wnt/β-catenin signaling pathway

OBJECTIVE

Emerging evidence suggests aberrant microRNAs (miRNAs) expression is involved in cancer development through multiple. Although miR338 has shown to have tumor suppression ability and anti-migration effects in some cancers, its regulatory role and molecular mechanism in the development of gastric cancer cells yet remains little known. This work aims to investigate miR-338 in regulating Wnt/β-catenin pathway in epithelial-mesenchymal transition (EMT) in gastric cancers.

MATERIALS AND METHODS

Human gastric cancer cells were transfected with either miR-338 mimic or erythropoietin-producing hepatocellular (Eph)A2-targeting siRNA. The biological function of miR-338 in gastric cancer cells was investigated using a MTT assay and invasion assay. Western blot assay was used to measure the levels of EphA2, GSK-3β, phospho-GSK-3βSer9, c-Myc, E-cadherin, Vimentin, and β-catenin of at protein level.

RESULTS

Our data showed that miR-338 inhibited proliferation, migration and invasion of human gastric cancer cells. miR-338 affected the Wnt/β-catenin pathway by increasing p-GSK-3βSer9 and decreasing GSK-3βSer9 and c-Myc at protein levels. EphA2 protein level was downregulated and positively correlated with EMT markers. Both silencing of EphA2 and transfection with miR-338 mimic resulted in the up-regulation of the EMT molecular marker E-cadherin and down-regulation of Vimentin and β-catenin at protein levels.

CONCLUSIONS

This study indicated that miR-338 is a potential tumor suppressor in gastric cancer and miR-338 inhibited EMT of gastric cancer cells through deactivation of Wnt/β-catenin signaling targeting at EphA2.

MAST3 modulates the inflammatory response and proliferation of fibroblast-like synoviocytes in rheumatoid arthritis

Via promoting synovitis, pannus growth and cartilage/bone destruction, fibroblast-like synovial cells (FLSs) play a significant role in the pathogenesis of rheumatoid arthritis (RA). In our study, rats were induced with complete freund's adjuvant (CFA) to be animal models for studying the RA pathogenesis. Microtubule-associated Serine/Threonine-protein kinase 3 (MAST3) has been documented to play a critical role in regulating the immune response of IBD (Inflammatory bowel disease) and involved in the process of cytoskeleton organization, intracellular signal transduction and peptidyl-serine phosphorylation, but its role in the progression of RA remains unknown and is warranted for investigation. So, we tried our best to investigate the mechanism and signaling pathway of MAST3 in RA progression. In the synovial tissue and FLSs of AA rats, we have found that MAST3 was significantly up-regulated than normal. Furthermore, MAST3 overexpression could promote proliferation and inflammatory response of FLSs. In the aspect of mechanism, we discovered that the expression of MAST3 might involve in NF-κB signaling pathway in RA. On the whole, our results suggested that MAST3 might promote the proliferation and inflammation of FLSs by regulating NF-κB signaling pathway.