Preparation of HA-MAO coatings on ß-type alloys and its corrosion resistance in high glucose environments.

Aim to provide practical clinical guidance for the treatment of implants in diabetic patients, this study investigated the corrosion mechanism of bionic coatings containing different Ca/P ratios in diabetic environments. The bionic coatings were prepared in ß-titanium alloys using micro-arc oxidation (MAO) technology and evaluated for corrosion mechanism, biocompatibility, and safety by cytotoxicity, electrochemical corrosion, and coating bonding force experiments. Ca and P from the electrolyte were integrated into the coating during MAO discharge process to form hydroxyapatite. The coating Ca/P ratio initially increased and then decreased with the electrolyte Ca/P ratio. In vitro cellular experiments demonstrated that increasing the porosity of HA-containing coatings would be beneficial to the growth of cells adhering to their surfaces. Corrosion tests revealed that the corrosion tendency of the coating at higher sugar content was more severe, and a proper elevation of the Ca/P ratio was better for the corrosion resistance of the coating. The bonding analysis of the coatings before and after corrosion showed that an increase in the Ca/P ratio would improve the bonding of the MAO coatings in higher glucose content environments, thus improving the safety of the implants in diabetic patients.

Effects of K2TiF6 and Electrolyte Temperatures on Energy Consumption and Properties of MAO Coatings on 6063 Aluminum Alloy.

To decrease energy consumption and improve the performance of micro-arc oxidation (MAO) films on 6063 Al alloy, a policy of K2TiF6 additive and electrolyte temperature control was adapted. The specific energy consumption relied on the K2TiF6 additive and more particularly on the electrolyte temperatures. Scanning electron microscopy demonstrates that electrolytes with 5 g/L K2TiF6 can effectively seal the surface pores and increase the thickness of the compact inner layer. Spectral analysis shows that the surface oxide coating consists of γ-Al2O3 phase. Following 336 h of the total immersion process, the impedance modulus of the oxidation film, prepared at 25 °C (Ti5-25), remained 1.08 × 106 Ω·cm2. Moreover, Ti5-25 has the best performance/energy-consumption ratio with a compact inner layer (2.5 ± 0.3 µm). This research found that the time of the big arc stage increased with the temperature, resulting in producing more internal defects in the film. In this work, we employ a dual-track strategy of additive and temperature providing an avenue to reduce the energy consumption of MAO on alloys.

Microstructure and Tribo-Behavior of WC-Cr3C2-Ni Coatings by Laser Cladding and HVAF Sprayed: A Comparative Assessment.

SK5 steel is the base material used for the preparation of the wrinkle scraper, whose service life strongly affects the working efficiency and economic benefits. In this work, WC-Cr3C2-Ni coating was deposited on the SK5 steel substrate by using High-velocity air fuel spray (HVAF) and Laser cladding (LC) processes respectively, named HVAF-WC coating and LC-WC coating. The microstructure and wear resistance of both coatings were analyzed, and were compared with the substrate sample. Results showed that the coatings were adhesive well onto the substrate. More WC with fine crystals is retained in HVAF-WC coating due to low flame flow temperature, while WC of LC-WC coating is characterized by columnar crystals. The wear rate of HVAF-WC and LC-WC coating was 4.00 × 10-7 mm3/(N•m) and 3.47 × 10-6 mm3/(N•m), respectively, which was two and one orders of magnitude lower than SK5 steel with 3.54 × 10-5 mm3/Nm. HVAF-WC coating exhibited the best wear resistance because of significant fine grain strengthening, which wear mechanism is mainly dominated by abrasive wear. Thus, it was thought that HVAF-WC coating is more effective ways to improve the wear resistance of SK5 steel, comparing with LC-WC coating.

Linc01555 promotes proliferation, migration and invasion of gastric carcinoma cells by interacting with Notch signaling pathway.

PURPOSE: To detect the expression level of long non-coding ribonucleic acid 01555 (linc01555) in gastric cancer (GC) tissues and cells, and its effects on the biological functions of GC cells. METHODS: The relative expression of linc01555 in 61 cases of GC and para-carcinoma tissues and GC cells was detected via quantitative reverse transcription-polymerase chain reaction (qRT-PCR). GC cells were divided into experimental group (si-linc01555) and control group (si-NC), and the interference efficiency was detected through qRT-PCR. The effects of interference in linc01555 expression on GC cell proliferation, colony formation ability, migration and invasion were determined using cell counting kit-8 (CCK-8) assay, colony formation assay, wound healing assay and Transwell assay. Moreover, the expressions of molecular markers in the downstream Notch pathway were detected using western blotting. RESULTS: The results of qRT-PCR showed that the expression of linc01555 was upregulated in GC tissues and cells. The results of CCK-8 assay revealed that the proliferative activity of GC cells declined after interference in linc01555 expression. It was found in colony formation assay that the proliferation ability of GC cells declined after interference in linc01555 expression, and it was observed in wound healing assay that the cell migration ability in the experimental group was weakened compared with that in the control group. According to the results of transwell assay, both migration and invasion ability of GC cells declined after interference in linc01555 expression. Finally, the western blotting showed that there were changes in the expressions of molecular markers in the Notch signaling pathway after interference in linc01555 expression. CONCLUSIONS: The expression of linc01555 is upregulated in GC tissues and cells, and the highly-expressed linc01555 promotes the proliferation, invasion and metastasis of GC cells through the Notch signaling pathway.

CXCL3 overexpression promotes the tumorigenic potential of uterine cervical cancer cells via the MAPK/ERK pathway.

CXCL3 belongs to the CXC-type chemokine family and is known to play a multifaceted role in various human malignancies. While its clinical significance and mechanisms of action in uterine cervical cancer (UCC) remain unclear. This investigation demonstrated that the UCC cell line HeLa expressed CXCL3, and strong expression of CXCL3 was detected in UCC tissues relative to nontumor tissues. In addition, CXCL3 expression was strongly correlated with CXCL5 expression in UCC tissues. In vitro, HeLa cells overexpressing CXCL3, HeLa cells treated with exogenous CXCL3 or treated with conditioned medium from WPMY cells overexpressing CXCL3, exhibited enhanced proliferation and migration activities. In agreement with these findings, CXCL3 overexpression was also associated with the generation of HeLa cell tumor xenografts in athymic nude mice. Subsequent mechanistic studies demonstrated that CXCL3 overexpressing influenced the expression of extracellular signal-regulated kinase (ERK) signaling pathway associated genes, including ERK1/2, Bcl-2, and Bax, whereas the CXCL3-induced proliferation and migration effects were attenuated by exogenous administration of the ERK1/2 blocker PD98059. The data of the current investigation support that CXCL3 appears to hold promise as a potential tumor marker and interference target for UCC.

IL-8 is upregulated in cervical cancer tissues and is associated with the proliferation and migration of HeLa cervical cancer cells.

Interleukin-8 (IL-8) serves an important function in chronic inflammation and cancer development; however, the underlying molecular mechanism(s) of IL-8 in uterine cervical cancer remains unclear. The present study investigated whether IL-8 and its receptors [IL-8 receptor (IL-8R)A and IL-8RB] contributed to the proliferative and migratory abilities of HeLa cervical cancer cells, and also investigated the potential underlying molecular mechanisms. Results demonstrated that IL-8 and its receptors were detected in HeLa cells, and levels of IL-8RA were significantly increased compared with those of IL-8RB. Furthermore, the level of IL-8 in cervical cancer tissues was significantly increased compared with that in normal uterine cervical tissues, and migratory and proliferative efficiencies of HeLa cells treated with exogenous IL-8 were increased, compared with untreated HeLa cells. In addition, exogenous IL-8 was able to downregulate endocytic adaptor protein (NUMB), and upregulate IL-8RA, IL-8RB and extracellular signal-regulated protein kinases (ERKs) expression levels in HeLa cells. Results suggest that IL-8 and its receptors were associated with the tumorigenesis of uterine cervical cancer, and exogenous IL-8 promotes the carcinogenic potential of HeLa cells by increasing the expression levels of IL-8RA, IL-8RB and ERK, and decreasing the expression level of NUMB.

Overexpression of CXCL3 can enhance the oncogenic potential of prostate cancer.

PURPOSE: CXCL3 and its receptor CXCR2 were considered to play particularly important roles in the progression of malignancies. However, the investigations about CXCL3/CXCR2 axis in prostate cancer have been poorly involved. Herein we firstly reported our studies on the expression and biological roles of CXCL3 and CXCR2 in prostate cancer. METHODS: Expression levels of CXCL3 and CXCR2 in prostate cancer cell lines (PC-3, DU145 and LNCaP), immortalized prostate stromal cell line (WPMY-1) and immortalized prostate epithelial cell line (RWPE-1) were investigated by RT-PCR, ELISA and western blot, whereas expression levels of CXCL3 in a prostate tissue microarray were detected by immunohistochemistry. Cell counting kit-8 and transwell assays were, respectively, utilized to determine the effects of exogenous CXCL3 on the cell proliferation and migration. We further examined whether CXCL3 could regulate the expression of genes correlated with prostate tumorigenesis by RT- PCR. RESULTS: Elevated expression of CXCR2 was detected in DU145, LNCaP and RWPE-1. Moreover, high-level CXCL3 can be secreted by PC-3 and RWPE-1, and CXCL3 protein expression level in tissue microarray is concordant with prostate cancer metastasis. Exogenous CXCL3 does not contribute to proliferation, but has a significant effect on migration of prostate cancer cells and RWPE-1. Finally, our data showed that exogenous CXCL3 can regulate the expression of genes including ERK, TP73, NUMB, BAX and NDRG3. CONCLUSION: Our findings suggest that CXCL3 and its receptor CXCR2 are overexpressed in prostate cancer cells, prostate epithelial cells and prostate cancer tissues, which may play multiple roles in prostate cancer progression and metastasis.

Electrochemical sensor based on molecularly imprinted film at Au nanoparticles-carbon nanotubes modified electrode for determination of cholesterol.

A novel electrochemical sensor for cholesterol (CHO) detection based on molecularly imprinted polymer (MIP) membranes on a glassy carbon electrode (GCE) modified with multi-walled carbon nanotubes (MWNTs) and Au nanoparticles (AuNPs) was constructed. p-Aminothiophenol (P-ATP) and CHO were assembled on the surface of the modified GCE by the formation of Au-S bonds and hydrogen-bonding interactions, and polymer membranes were formed by electropolymerization in a polymer solution containing p-ATP, HAuCl4, tetrabutylammonium perchlorate (TBAP) and the template molecule CHO. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) measurements were used to monitor the electropolymerization process and its optimization, which was further characterized by scanning electron microscopy (SEM). The linear response range of the MIP sensor was between 1×10(-13) and 1×10(-9)molL(-1), and the limit of detection (LOD) were 3.3×10(-14)molL(-1). The proposed system has the potential for application in clinical diagnostics of cholesterol with high-speed real-time detection capability, low sample consumption, high sensitivity, low interference and good stability.

Effects of platycodins on liver complications of type 2 diabetes.

The aim of the current study was to investigate the therapeutic effects and mechanism of platycodin in liver complications of type 2 diabetes. All rats were randomly divided into two groups: The control group (normal diet) and the model group (a high­fat and high­sugar diet). The model group was injected with 2% streptozocin (25 mg/kg body weight) through the tail vein following 4 weeks of dieting. After a total of 8 weeks of dieting, fasting blood glucose (FBG) and liver function were examined. The high­fat and high­sugar diet was continued in the successful model rats, which were randomly divided into four groups and treated with the following doses of platycodins: The untreated, and 50, 100 and 200 mg/kg body weight/day groups. Platycodins treatment lasted for 12 weeks. Platycodins treatment at a dose of 200 mg/kg body weight/day reduced the FBG, glutamate pyruvate transaminase (GPT), glutamic oxalacetic transaminase, triglycerides, total cholesterol (TC), low­density lipoprotein (LDL) and liver index levels compared with the untreated group (P<0.05), while the high­density lipoprotein levels increased (P<0.05). Furthermore, FBG, GPT, TC and LDL levels were returned to the normal level. This dose also increased the expression of BMP­9 mRNA and BMP­9 protein, and reduced the expression of Smad­4 mRNA and Smad­4 protein. These findings indicate that platycodins can rectify disorders of blood glucose and lipid metabolism, improve liver index and protect liver function in liver complications of type 2 diabetes. The current study suggests that this therapeutic effect is mediated through the BMP­9/Smad­4 pathway.

Necessity of screening water chestnuts for microcystins after cyanobacterial blooms break out.

Water chestnut is one of the most popular vegetables in Asian countries that grows in shallow water. Eighteen water chestnut samples were collected from Lake Tai and six samples were bought at markets in Wuxi, China, in October 2007. Extraction solution of water chestnut was cleaned up with a solid phase extraction column and immunoaffinity chromatography cartridges, then the microcystin (MC) level was detected by indirect competitive enzyme-linked immunosorbent assay (ELISA) and liquid chromatography-mass spectrometry (LC-MS). The results of ELISA showed that there were six samples collected from Lake Tai which contained MCs; the highest level of total MCs was 7.02 ng/g. The results of LC-MS confirmed that MC-LR and MC-RR were present in five samples. The highest level of MC-LR was 1.02 ng/g and that of MC-RR was 4.44 ng/g. Heavy cyanobacterial blooms had occurred, and MCs were detected in water at the points in Lake Tai where MCs occurred in water chestnuts collected in 2007. MCs were not detected in the six samples bought at Wuxi markets. The results suggest that MCs can accumulate in water chestnuts, which is a potential hazard for human health.

Determination of microcystin-LR in water from Lake Tai, China.

Microcystin-LR (MC-LR) is a heptapeptide hepatotoxin produced by cyanobacteria. Immunoaffinity chromatography (IAC) column was prepared with CNBr-activated Sepharose 4B and monoclonal antibody of MC-LR. Water sample was cleaned up by IAC column and the content of MC-LR in water was determined by liquid chromatography-mass spectrometry (LC-MS). The results suggested that the IAC column exhibited highly selective specificity for MC-LR and selective removed interference from complex water sample. Water sample was concentrated for 2,000-fold through once purification. Cyanobacterial blooms had broken out in 2007 in Lake Tai, the third largest freshwater lake in China. Water samples from two parts of Lake Tai had been analyzed. The highest concentration of MC-LR in water from Lake Tai was 0.522 microg/L.

[Production and characterization of gold labeled monoclonal antibody against MC-LR].

OBJECTIVE: Production of the gold labeled monoclonal antibody against MC-LR. Study the simple mechanism of the conjugation by the spectral analysis. METHODS: Production and purification monoclonal antibodies against MC-LR by hybridoma technology. Production the 20nm colloidal gold and label the monoclonal antibody. Study the gold--McAb conjugate by the spectroanalysis. RESULTS: Monoclonal antibody produced by the hybridoma cells were tested for subtypes and designated as IgG2a for 8C11. The titers of antibody in ascites was 108.The IC50 for MC-LR was around 3ng/ml. The IgG molecule weight was 1.5 x 10(5). The structure of the antibody was altered to more tighter and stabler. CONCLUSION: Product the gold labeled monoclonalantibody against MC-LR conjugate successfully and keep the antige-binding determinant.

[Production purification and characterization of polyantibodies against microcystin-LR].

OBJECTIVE: Production and characterization the polyantibodies against MCYST-LR. METHODS: microcystin-LR (MC-LR) was conjugated to KLH, then immune the rabbit by the routine method. Purify the antiserum by centrifugal and saturated sulfuric ammonium precipitated methods. Count the affinity constant and measure the titers, IC50 Value and the sensitivity. RESULTS: The titers of the antiserum is over 25600. IC50 value is about from 0.1 ng/ml to 1 ng/ml. The across-reactivity ratio to MC-LW and MC-LR is about from 0.1% to 20%.

[Preparation and characterization of immunogen against microcystin LR].

OBJECTIVE: To prepare Microcystins-LR (MC-LR) conjugates with the carrier protein for developing a new immune assay for MC-LR. METHODS: MC-LR was coupled to BSA or KLH by "activated ester" and "water-soluble carbodimide". Measure the combine ratio of MC-LR with KLH or BSA by the UV scanning or the Bradford's method. RESULTS: The results are 9.1 and 9.4. New Zealand rabbits was immunized by MC-LR-KLH. The titer of the polyantibodies was over 25,600 measured by id ELISA. CONCLUSION: MC-LR-KLH was proved the suitable immunogen against MC-LR.