Effect of Sodium Content on the Electrochemical Performance of Li-Substituted, Manganese-Based, Sodium-Ion Layered Oxide Cathodes.

Li-substituted, manganese-based, layered oxides NaxLi0.18Mn0.66Co0.17Ni0.17O2+δ (x = 0.54, 0.66, 0.78, and 0.90) have been investigated as one kind of high-performance cathode materials for sodium ion batteries (SIBs). Phase compositions and local structures of the cathode materials with varying sodium content were elucidated by powder X-ray diffraction (PXRD) and atomic-scale high angle annular dark field scanning transmission electron microscope (HAADF-STEM), which demonstrates that a Li-O'3 phase was aroused in P2-type sodium layered oxide matrix forming a Na-P2/Li-O'3 hybrid structure. More importantly, the effect of sodium content on the preferential exposure of (102) and (104) facets and surface morphology of the cathode particles has been comprehensively studied, as well as their relationship with electrochemical performance. It reveals that, in addition to the preferential growth of (102) and (104) facets that has been proved to enhance the capacity and rate performance of the layered oxides, the smooth surface finish of the particles also plays a vital role in deciding the electrochemical performance. The layered sodium cathode material with a sodium content of 0.66 possesses sufficient exposure of (102) and (104) facets and smooth side surface, resulting in the superior capacities under various C rates (187 mAh/g at 0.2 C and 114 mAh/g at 5 C) comparing to the cathode materials with all other sodium contents. The mechanism has also been proposed in this study. These findings presented herein open up new strategies to design high performance sodium layered oxide cathode.

Bioinspired leaves-on-branchlet hybrid carbon nanostructure for supercapacitors.

Designing electrodes in a highly ordered structure simultaneously with appropriate orientation, outstanding mechanical robustness, and high electrical conductivity to achieve excellent electrochemical performance remains a daunting challenge. Inspired by the phenomenon in nature that leaves significantly increase exposed tree surface area to absorb carbon dioxide (like ions) from the environments (like electrolyte) for photosynthesis, we report a design of micro-conduits in a bioinspired leaves-on-branchlet structure consisting of carbon nanotube arrays serving as branchlets and graphene petals as leaves for such electrodes. The hierarchical all-carbon micro-conduit electrodes with hollow channels exhibit high areal capacitance of 2.35 F cm-2 (~500 F g-1 based on active material mass), high rate capability and outstanding cyclic stability (capacitance retention of ~95% over 10,000 cycles). Furthermore, Nernst-Planck-Poisson calculations elucidate the underlying mechanism of charge transfer and storage governed by sharp graphene petal edges, and thus provides insights into their outstanding electrochemical performance.

Vertically-oriented graphene nanosheet as nano-bridge for pseudocapacitive electrode with ultrahigh electrochemical stability.

A hierarchical structure consisting of Ni-Co hydroxide nanosheets (NCHN) electrodeposited on vertically-oriented graphene nanosheets (GN) on carbon cloth (CC) was fabricated for high-performance pseudocapacitive electrodes. NCHN was uniformly distributed on GN, forming a sheet-on-sheet hierarchical structure. Such NCHN/GN/CC hybrid electrodes exhibit high capacitance and ultrahigh electrochemical-stability that structure and electrochemical properties of hybrid electrodes are not affected by the cyclic low-rate scanning (at 5 mV s-1 even over 1000 cycles). GN vertically grown on CC is used as nano-bridge between NCHN active materials and CC current collector, which effectively facilitates ion/charge transfer between the electrolyte and electrode, consequently leading to the ultrahigh electrochemical-stability of hybrid electrodes. To assess functional behavior, two-terminal flexible asymmetric supercapacitor devices with NCHN/GN/CC as positive electrode and GN/CC as negative electrode were assembled and electrochemically treated to demonstrate the ultrahigh electrochemical stability.

Decreased expression of SOX7 is correlated with poor prognosis in lung adenocarcinoma patients.

Lung adenocarcinoma is the most frequently histologic subtype and the most histologically heterogeneous form of lung cancer. De-regulation of Wnt/ß-catenin signaling pathway is implicated in lung carcinogenesis. SOX7, as a member of high mobility group (HMG) transcription factor family, plays a role in the modulation of the Wnt/ß-catenin signaling pathway. However, the expression pattern and clinicopathological significance of SOX7 in patients with lung adenocarcinoma is still unclear. To address this problem, the SOX7 mRNA expression was detected by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). Immunohistochemical studies were performed on 288 pairs of adjacent normal lung and lung adenocarcinoma tissues with complete follow-up records. Association of SOX7 protein expression with clinical outcomes was evaluated using the Kaplan-Meier method and a multivariate Cox proportional hazards regression model. SOX7 mRNA expression was significantly down-regulated in lung adenocarcinoma compared with matched adjacent normal tissues (P < 0.001). SOX7 protein was expressed in the cytoplasm of lung adenocarcinoma cells in 106/288 (36.8 %) of cases, whereas its immunoreactivities were predominantly located in the cytoplasm of the adjacent normal tissues. The reduced SOX7 expression was correlated with poor differentiation (P = 0.002), lymph node metastasis (P = 0.011) and advanced TNM stage (P = 0.006). Regarding patient survival, the overall survival and the disease-free survival rates were both significantly lower in patients with SOX7-negative tumors than in those with SOX7-positive tumors (P = 0.018 and 0.013, respectively). Multivariate analysis using a Cox proportional-hazards model demonstrated that SOX7 expression status was an independent prognostic factor predicting the overall survival and the disease-free survival of patients with lung adenocarcinoma (P = 0.021 and 0.016, respectively).Our data suggest that the decreased expression of SOX7 is an important feature of lung adenocarcinoma. The expression level of SOX protein may be a useful prognostic marker for patients with lung adenocarcinoma.

Synthesis and in vitro/in vivo anti-cancer evaluation of curcumin-loaded chitosan/poly(butyl cyanoacrylate) nanoparticles.

We have synthesized novel cationic poly(butyl) cyanoacrylate (PBCA) nanoparticles coated with chitosan, formulation of curcumin nanoparticles. The size and zeta potential of prepared curcumin nanoparticles were about 200 nm and +29.11 mV, respectively with 90.04% encapsulation efficiency. The transmission electron microscopy (TEM) study revealed the spherical nature of the prepared nanoparticles along with confirmation of particle size. Curcumin nanoparticles demonstrate comparable in vitro therapeutic efficacy to free curcumin against a panel of human hepatocellular cancer cell lines, as assessed by cell viability (3-[4,5-dimethylthiazol-2-yl]2,5-diphenyltetrazolium bromide assay [MTT assay]) and proapoptotic effects (annexin V/propidium iodide staining). In vivo, curcumin nanoparticles suppressed hepatocellular carcinoma growth in murine xenograft models and inhibited tumor angiogenesis. The curcumin nanoparticles' mechanism of action on hepatocellular carcinoma cells is a mirror that of free curcumin.

[Effect of Itk down regulation on cytokines production in Jurkat cell].

OBJECTIVE: To study the effect of Itk down regulation on Jurkat cell proliferation and inflammatory cytokines production, and provide useful data for Itk as an attractive target for potential drugs. METHODS: Three shRNAs against different region of Itk were constructed and cotransfected with pEGFP-C1-hItk. The shRNA, which can knock down Itk, was selected and packed into lentivirus. After Jurkat cells were transfected with shRNA lentivirus, the change of Itk protein expression, cell proliferation and cytokines production was observed. RESULTS: Itk mRNA was reduced about 55% in Jurkat cells transfected with Itk-shRNA1, compared with that in control cells shRNAnon (P < 0.05). Knocking down Itk expression had a profound inhibitory effect on Jurkat cell proliferation. In addition, there was a substantial decrease in level of cytokines, such as IL-2, IL-5, IL-10 and IFN-gamma, produced by cell transfected with Itk-shRNA1. CONCLUSION: Knocking down Itk expression can inhibit Jurkat cell proliferation and inflammatory cytokines production.

[Study on implant material of carbon/carbon composites].

This study was aimed to evaluate the biocompatibility and mechanical property of carbon/carbon composites. At first, carbon/carbon composites were prepared by chemical vapor deposition, and the mechanical property of carbon/carbon composites was tested. The biocompatibility of carbon/carbon composites was evaluated by cytotoxicity test, sensitization test, micronucleus test and implantation test. Mechanical property test showed such carbon/carbon composites are of good compression property and tension property. Cytotoxicity test showed that the leaching liquor of samples has no effect on the growth and proliferation of L-929 cells. The medullary micronucleus frequency of mouse was 2.3 per thousand +/- 0.7 per thousand in experiment group. The sensitization test showed that the skin of the subjects of experiment group had slight erythema and edema, which was 0.188 +/- 0.40 according to Magnusson and Kligman classification. Implantation test revealed that there was slight inflammation around the tissue after the implantation of sample. At 12 weeks, scanning electron microscopy and histopathological exam indicated that the samples of experiment group were of good histocompatibility; and in comparison with control group, there was no significant differences (P > 0.05). So these kinds of samples have good biocompatibility, mechanical property and prospects of clinical application.

Biological properties of carbon/carbon implant composites with unique manufacturing processes.

The goal was to manufacture carbon/carbon (C/C) composites through a unique procedure with improved biocompatibility and reduced debris release. C/C composites were prepared by chemical vapor deposition, and their biological properties were analyzed. With regard to mechanical properties, compressive strength/modulus was 219.1 MPa/9.72 GPa, flexural strength/modulus was 121.63 MPa/21.9 GPa, and interlaminar sheer was 15.13 GPa. Biocompatibility testing revealed: (1) the extract liquid from the C/C composites had no effect on cell proliferation; (2) the extract had no impact on micronucleus frequency as compared with the control groups (P > 0.05); (3) in vivo, there was mild tissue inflammation after implantation within the first 2 weeks, but there was no significant difference compared with the control group (P > 0.05); (4) the implants were well integrated into the host tissue, and debris was limited. The tested samples have excellent biocompatibilities and reduced release of debris. The demonstrated changes in manufacturing procedures are promising.

[Expression of stathmin mRNA and protein in laryngeal squamous cell carcinoma and its clinical implication].

OBJECTIVE: To investigate the expressions of stathmin gene and its coding protein in laryngeal squamous cell carcinoma, and to explore the relationship between stathmin gene and the biological behaviors of laryngeal squamous cell carcinoma for understanding the tumorigenicity and development of laryngeal squamous cell carcinoma. METHODS: Laryngeal carcinoma tissues (studying group) in the tumors center and laryngeal normal tissues (control group) parted from 1.0 cm of the safe borderline of the tumors were took from 38 patients with laryngeal squamous cell carcinoma while they were in operation. Semiquantitative method of reverse transcriptase polymerase chain reaction (RT-PCR) was used to analyze the expression level of stathmin mRNA, and immunohistochemical staining (frozen section) was used to detect the expressions of stathmin protein, in laryngeal carcinoma tissues and laryngeal normal tissues of 38 cases, respectively. RESULTS: mRNA of stathmin gene was all positively expressed in laryngeal carcinoma tissues and in laryngeal normal tissues of 38 cases by RT-PCR. However, stathmin mRNA was obviously overexpressed in laryngeal carcinoma tissues than that in laryngeal normal tissues (t = 9.655, P < 0.05). Immunohistochemical staining showed stathmin protein was positively expressed in laryngeal carcinoma tissues of 26 cases (26/38, 68.4%), and mild-positively expressed in laryngeal normal tissues in 13 cases (13/38, 34.2%). There was significant difference between the expression rate of stathmin protein in laryngeal carcinoma tissues and in laryngeal normal tissues (chi2 = 8.901, P < 0.05). Meanwhile, the expression level of stathmin mRNA and the positive-expressed rate of stathmin protein in laryngeal carcinoma tissues of the advanced stage patients group (III stage and IV stage) were significantly higher than these in laryngeal carcinoma tissues of I and II stage patients group (t = 6.284, chi2 = 5.810, P < 0.05), and they were also significantly higher in laryngeal carcinoma tissues of the patients group with cervical lymph node metastasis than in laryngeal carcinoma tissues of the patients group without cervical lymph node metastasis (t = 9.350, chi2 = 6.923, P < 0.05). CONCLUSIONS: The expression levels of stathmin gene and protein were significantly higher in laryngeal squamous cell carcinoma than these in laryngeal normal tissues, the levels are also significantly higher in advanced stage patients group (III stage and IV stage) than in the early stage patients group (I and II), and they are also related to the cervical lymph node metastasis of carcinoma. Stathmin gene may play an important role in the pathogenesis and development of laryngeal carcinoma and may be related to its prognosis.

[Study on biocompatibility of hydroxyapatite/high density polyethylene (HA/HDPE) nano-composites artificial ossicle].

This study was aimed to evaluate the biocompatibility of Hydroxyapatite/High density polyethylene (HA/ HDPE) nano-composites artificial ossicle. The percentage of S-period cells were detected by flow cytometry after L929 cells being incubated with extraction of the HA/HDPE nano-composites; the titanium materials for clinical application served as the contrast. In addition, both materials were implanted in animals and the histopathological evaluations were conducted. There were no statistically significant differences between the two groups (P >0.05). The results demonstrated that the HA/HDPE nano-composite artificial ossicle made by our laboratory is of a good biocompatibility and clinical application outlook.

[The expressions and clinical significance of tumor suppressor gene CX26 in laryngeal squamous cell carcinoma].

OBJECTIVE: To investigate the expressions of tumor suppressor gene CX26 mRNA and coding protein in laryngeal squamous cell carcinoma, and to explore the relationship between CX26 gene and the biological behaviors of laryngeal squamous cell carcinoma for understanding the tumorigenicity and development of laryngeal squamous cell carcinoma. METHOD: Laryngeal carcinoma tissues (studying group), which takeda from the center of tumors and laryngeal normal tissues (control group) takeda at the place of 1.0 cm out of the edge of the tumors, were took from 38 patients with laryngeal squamous cell carcinoma while they were in operation. Semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) was used to analyze the expression level of CX26 mRNA, and immunohistochemical staining (frozen section) was used to detect the expression of CX26 protein in laryngeal carcinoma tissues and laryngeal normal tissues of 38 cases, respectively. RESULT: mRNA of CX26 gene was all positively expressed in laryngeal carcinoma tissues and laryngeal normal tissues of 38 cases by RT-PCR. However, CX26 mRNA was obviously down-regulated in laryngeal carcinoma tissues than that in laryngeal normal tissues (P < 0.05). Immunohistochemical staining showed CX26 protein was strong-positively expressed in laryngeal normal tissues in 34 cases (89.5%), while it was positively expressed in laryngeal carcinoma tissues in 18 cases (47.4%), and with the location alteration of CX26 protein in laryngeal carcinoma cells. There was significant difference between the expression rate of CX26 protein in laryngeal carcinoma tissues and in laryngeal normal tissues (P < 0.05). Meanwhile, the expression level of CX26 mRNA and the positive-expressed rate of CX26 protein of the laryngeal carcinoma tissues in the advanced stage patients group (III stage and IV stage) were significantly lower than these in the early stage patients group (I and II) (P < 0.05), and it was significantly lower in those who have a cervical lymph node metastasis than those without metastasis. (P < 0.05). Moreover, the expression level of CX26 mRNA and the positive-expressed rate of CX26 protein reduced along with the reduction of pathological differentiation, and there was significant difference among the well-differentiated group, moderately-differentiated group and poorly-differentiated group (P < 0.05). CONCLUSION: CX26 gene may play an important role in the pathogenesis and development of laryngeal carcinoma and may be related to its prognosis.

[Study on biocompatibility of MIM 316L stainless steel].

This study was aimed to evaluate the biocompatibility of metal powder injection molding (MIM) 316L stainless steel. The percentage of S-period cells was detected by flow cytometry after L929 cells being incubated with extraction of MIM 316L stainless steel, and titanium implant materials for clinical application were used as control. In addition, both materials were implanted in animals and the histopathological evaluations were carried out. The statistical analyses show that there are no significant differences between the two groups (P > 0.05), which demonstrate that MIM 316L stainless steel has good biocompatibility.

[Hydroxyapatite nanoparticles: a novel material of gene carrier].

Hydroxyapatite nanoparticles were prepared in low Ca/P ratio by a kind of electrodeposition-hydrothermal process. The suspension of nanoparticles was cultured with SGC-7901 cells; metabolically active cells were evaluated by MTT analysis. Cells grew well and the nanoparticles in the concentration range of 10-100 microg/ml had no adverse effect on the cell viability. The results show that the nanoparticles have excellent biocompatibility with cells. Agrose gel electrophoresis analysis demonstrated that the nanoparticles had the potential to adsorb EGFP-N1 at the pH ranging between 2 to 7. Nanoparticle-DNA complex could transfer EGFP-N1 into the SGC-7901 cells, and the confocal microscopy analysis revealed that the cells with green fluorescence showed the efficiency of nanoparticle uptake to be about 80% of the efficiency of the Lipofectmine TM 2 000 uptake. In vivo, nanoparticles and DNA-nanoparticle complex were injected into mice respectively via tail-vein, and the mice grew well in two weeks. The liver, kidney, and brain of the mice were sampled and detected with electron microscopy, and all of these exhibited biodistribution of nanoparticles. This study demonstrates that Hydroxyapatite nanoparticles could be used as gene carriers.