Lei Zhang
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Pubmed
Journal: Angewandte Chemie (International ed. in English)
October/21/2016
Abstract

Efficient charge separation and light absorption are crucial for solar energy conversion over solid photocatalysts. This paper describes the construction of Pt@TiO2 @In2 O3 @MnOx mesoporous hollow spheres (PTIM-MSs) for highly efficient photocatalytic oxidation. TiO2 -In2 O3 double-layered shells were selectively decorated with Pt nanoparticles and MnOx on the inner and outer surfaces, respectively. The spatially separated cocatalysts drive electrons and holes near the surface to flow in opposite directions, while the thin heterogeneous shell separates the charges generated in the bulk phase. The synergy between the thin heterojunctions and the spatially separated cocatalysts can simultaneously reduce bulk and surface/subsurface recombination. In2 O3 also serves as a sensitizer to enhance light absorption. The PTIM-MSs exhibit high photocatalytic activity for both water and alcohol oxidation.

Pubmed
Journal: Journal of oral pathology & medicine : official publication of the International Association of Oral Pathologists and the American Academy of Oral Pathology
August/14/2016
Abstract

OBJECTIVE

Many reports indicated LATS2 was a component of the Hippo pathway, could phosphorylate and inactivate YAP, acted as a tumor suppressor in human cancers. But few studies investigated the role of LATS2 in oral squamous cell carcinoma (OSCC) and clarified the mechanisms of regulation of LATS2 expression.

METHODS

The expressions of LATS2 and phosphorylated YAP were detected by Western blotting in HN6 cells treated with TNF-α in different time and different dose. Luciferase reporter assays were performed to detect whether YAP can be phosphorylated by LATS2 in HN6 cells. Cell proliferation, anchorage independent growth in soft agar, transwell cell invasion assay, and nu mice in vivo xenografts growth were performed to study the effects of overexpression of LATS2 on OSCC cells.

RESULTS

In this study, we confirmed that YAP can be phosphorylated by LATS2. LATS2 can be dose- and time-dependently induced by TNF-α in HN6 cells. Overexpression of LATS2 inhibited cell proliferation, colony formation, cell invasion, and in vivo xenografts growth in OSCC cells.

CONCLUSIONS

LATS2 could be induced by TNF-alpha and inhibited cell proliferation and invasion by phosphorylating YAP in OSCC cells. LATS2 might play a role in the tumorigenesis of OSCC and might be a potential therapeutic target in OSCC treatment.

Pubmed
Journal: Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine
November/29/2016
Abstract

Scaffolds are of great importance to the success of tissue engineering. Poly(l-lactide-co-glycolide) acid is one of the most commonly used biopolymers. This study develops a novel low-temperature deposition machine using screw extrusion to fabricate poly(l-lactide-co-glycolide) acid scaffolds. The screw extrusion process of poly(l-lactide-co-glycolide) acid is analysed, and the relationship between flow rate and processing parameters is examined. This relationship provides guidelines for optimizing the processing parameters. The major components and design strategy of the fabrication system are introduced. Measures are proposed to control the leakage of materials, and optimal processing parameters are determined. The machine is also equipped with a double-screw extrusion nozzle system; preliminary results demonstrate its capacity to fabricate gradient scaffolds. Porous structure characterization using mercury porosimetry demonstrates that the fabrication system is able to fabricate poly(l-lactide-co-glycolide) acid scaffolds that are both macroporous and microporous.

Pubmed
Journal: European journal of radiology
February/23/2011
Abstract

OBJECTIVE

This study was to analyze the magnetic resonance imaging (MRI) features of hepatocellular carcinoma (HCC) with bile duct tumor thrombi, and explore their correlations to histopathology to improve the accuracy of diagnosis.

METHODS

21 patients with pathologically confirmed HCC with bile duct tumor thrombi was performed with a superconducting 1.5-T MR imager within two weeks before operation. Magnetic resonance cholangiopancreatography (MRCP) was performed on 18 patients. Images were retrospectively assessed for the size, location and MRI manifestations of HCC lesions and associated bile duct tumor thrombi. The differentiation of HCC lesions and the pathologic changes of bile duct tumor thrombi were retrospectively analyzed under microscope.

RESULTS

The average diameter of HCC lesions was 5.8±2.8 cm, and ≤5.0 cm in nine cases. Capsule formation was observed on MRI or pathology in 4 cases of HCC (19%). Of the 21 cases with bile duct tumor thrombi, 20 were clearly presented on MRI as cord-like or columnar masses in the bile duct with proximal cholangiectasis. The tumor thrombi showed slightly hypointense on T1WI and slightly hyperintense on T2WI. On enhanced scan, three cases of tumor thrombi, which were mainly consisted of necrotic tissue, did not show enhancement; 17 cases, which were mainly consisted of cancer cells, showed mild or moderate enhancement. On magnetic resonance cholangiopancreatogram (MRCP), 14 cases of tumor thrombi presented as filling defect in the bile duct, abrupt obstruction of the bile duct, and cholangiectasis above the obstruction; four presented as dilated intra-hepatic bile ducts with missing common bile duct. Of the 21 patients, 16 had biliary hemorrhage; three also had tumor thrombi in the portal vein. Seventeen of the 21 HCC with biliary thrombi were poorly differentiated, unencapsulated and with an invasive growth. Nineteen of 21 bile duct tumor thrombi did not invade the bile duct wall and could be easily extracted.

CONCLUSIONS

MRI plays a valuable role in diagnosing HCC with bile duct tumor thrombi and identifying the extent of the thrombi; the MRI features of HCC with bile duct tumor thrombi are associated with its pathologic changes.

Pubmed
Journal: Biochimica et biophysica acta
April/29/2009
Abstract

Extracellular matrix proteins play crucial roles in plant development, morphogenesis, cell division, and proliferation. To identify extracellular proteins that regulate cell growth, the soluble proteins of extracellular matrix were extracted from suspension-cultured rice cells for different lengths of time. The extract obtained from 3-d cultures was found to increase cells' fresh weight, while extracts from 6-d and 9-d cultures showed no effect on cells' growth. A comparative proteomic analysis was used to identify soluble extracellular proteins differentially expressed between 3 and 6 days in suspension-cultured cells. Ten unique protein spots were isolated and identified by mass spectrometry. Among them, included a cysteine protease (OsCP) and a putative cysteine protease inhibitor (cystatin, OC-I). OsCP has been down regulated in vivo using RNAi transgenic lines. The fresh and dry weight growth rates of OsCP RNAi cell lines were lower than empty vector control. Recombinant protein of OC-I could inhibit the OsCP protease activity, also it could inhibit the weight increase of suspension-culture cell as well as extracellular protease activity. These results suggest that OsCP and OC-I may be involved in the process of suspension-cultured rice cells proliferation.

Pubmed
Journal: Talanta
May/11/2015
Abstract

A novel, simple and selective electrochemical method was developed for simultaneous determination of bisphenol F (BPF) and bisphenol AF (BPAF) in aqueous media (phosphate buffer solution, pH 6.0) on carboxyl functionalized multi-walled carbon nanotubes modified glassy carbon electrode (MWCNT-COOH/GCE) using differential pulse voltammetry (DPV). In DPV, MWCNT-COOH/GCE could separate the oxidation peak potentials of BPF and BPAF present in the same solution though, at the bare GCE, the peak potentials were indistinguishable. The results showed that the electrochemical sensor exhibited excellent electrocatalytic activity towards the oxidation of the two analytes. The peak current in DPV of BPF and BPAF increased linearly with their concentration in the ranges of 0.6-1.6 mmol/L BPF and 0.6-1.6 mmol/L BPAF. The detection limits were 0.1243 mmol/L and 0.1742 mmol/L (S/N=3) correspondingly. The modified electrode was successfully used to simultaneously determine BPF and BPAF in real samples.

Pubmed
Journal: Organic & biomolecular chemistry
May/11/2015
Abstract

DABCO-catalyzed [3 + 2] annulation reaction of sulfamate-derived cyclic imines with isocyanoacetate proceeds under mild conditions, providing sulfamate-fused 2-imidazolines in moderate to excellent yields with moderate to excellent diastereoselectivities.

Pubmed
Journal: Diabetes research and clinical practice
August/26/2015
Abstract

OBJECTIVE

The aim of this study is to investigate sleep quality and quality of life, and to assess the relationship between sleep quality and quality of life in Chinese patients with type 2 diabetes mellitus (T2DM).

METHODS

944 patients with T2DM were enrolled in our study. General characteristics and laboratory testing such as glycosylated hemoglobin A1c (HbA1c) were measured. Each patient completed a Chinese version of the Pittsburgh sleep quality index (PSQI) and the diabetes specificity quality of life scale (DSQL) questionnaires. A PSQI global score >7 was defined as poor sleep quality. A global DSQL score <40 was defined as a good quality of life. Multiple logistic regression analysis was used to examine the relationships between PSQI and DSQL.

RESULTS

Poor quality of life in participants was associated with a longer duration of diabetes, a greater number of diabetes complications, no alcohol drinking, poor glycemic control and having depression and anxiety (all P<0.001). Of the participants, 33.6% of them were poor sleepers according to their PSQI. Poor sleepers had significantly lower DSQL (P<001). After adjustment for confounders, poor sleep quality was positively associated with a lower health-related quality of life (OR: 3.67, 95% CI: 1.30-10.33, P<0.001).

CONCLUSIONS

Our results suggest that poor sleep is prevalent in T2DM and inversely associated with quality of life. It is necessary for primary health-care workers to include sleep related knowledge in diabetes self-management programs to improve sleep quality in diabetes patients.

Pubmed
Journal: Toxicology and applied pharmacology
August/9/2015
Abstract

With application of nano-sized nickel-containing particles (Nano-Ni) expanding, the health concerns about their adverse effects on the pulmonary system are increasing. However, the mechanisms for the pulmonary toxicity of these materials remain unclear. In the present study, we focused on the impacts of NiO nanoparticles (NiONPs) on sirtuin1 (SIRT1), a NAD-dependent deacetylase, and investigated whether SIRT1 was involved in NiONPs-induced apoptosis. Although the NiONPs tended to agglomerate in fluid medium, they still entered into the human bronchial epithelial cells (BEAS-2B) and released Ni(2+) inside the cells. NiONPs at doses of 5, 10, and 20μg/cm(2) inhibited the cell viability. NiONPs' produced cytotoxicity was demonstrated through an apoptotic process, indicated by increased numbers of Annexin V positive cells and caspase-3 activation. The expression of SIRT1 was markedly down-regulated by the NiONPs, accompanied by the hyperacetylation of p53 (tumor protein 53) and overexpression of Bax (Bcl-2-associated X protein). However, overexpression of SIRT1 through resveratrol treatment or transfection clearly attenuated the NiONPs-induced apoptosis and activation of p53 and Bax. Our results suggest that the repression of SIRT1 may underlie the NiONPs-induced apoptosis via p53 hyperacetylation and subsequent Bax activation. Because SIRT1 participates in multiple biologic processes by deacetylation of dozens of substrates, this knowledge of the impact of NiONPs on SIRT1 may lead to an improved understanding of the toxic mechanisms of Nano-Ni and provide a molecular target to antagonize Nano-Ni toxicity.

Pubmed
Journal: Ultrasonics sonochemistry
April/20/2017
Abstract

The ultrasonic extraction of oils is a typical physical processing technology. The extraction process was monitored from the standpoint of the oil quality and efficiency of oil extraction. In this study, the ultrasonic cavitation fields were measured by polyvinylidene fluoride (PVDF) sensor. Waveform of ultrasonic cavitation fields was gained and analyzed. The extraction yield and oxidation properties were compared. The relationship between the fields and cavitation oxidation was established. Numerical calculation of oscillation cycle was done for the cavitation bubbles. Results showed that the resonance frequency, fr, of the oil extraction was 40kHz. At fr, the voltage amplitude was the highest; the time was the shortest as reaching the amplitude of the waveform. Accordingly, the cavitation effect worked most rapidly, resulting in the strongest cavitation intensity. The extraction yield and oxidation properties were closely related to the cavitation effect. It controlled the cavitation oxidation effectively from the viewpoint of chemical and physical aspects.

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