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The coupling of Arg-Gly-Asp-Val (RGDV) and gemcitabine led to a hypothesis that the conjugate (RGDV-gemcitabine) could inhibit tumor metastasis. To confirm this hypothesis the activities of RGDV-gemcitabine inhibiting tumor metastasis in vitro and in vivo were presented for the first time. AFM (atomic force microscopy) imaged that RGDV-gemcitabine was able to adhere onto the surface of serum-starved A549 cells, to block the extending of the pseudopodia. Thereby RGDV-gemcitabine was able to inhibit the invasion, migration and adhesion of serum-starved A549 cells in vitro. On C57BL/6 mouse model RGDV-gemcitabine dose dependently inhibited the metastasis of planted tumor towards the lung and the minimal dose was 0.084 µmol/kg/3 days. The decrease of serum TNF-α (tumor necrosis factor), IL-8 (interleukin-8), MMP-2 (matrix metalloprotein-2) and MMP-9 (matrix metalloprotein-9) of the treated C57BL/6 mice was correlated with the action pathway of RGDV-gemcitabine inhibiting the metastasis of the planted tumor towards lung.

Wenchao Liu1,2, Yujia Mao1,2, Xiaoyi Zhang1,2, Yaonan Wang1,2, Jianhui Wu1,2, Shurui Zhao1,2, Shiqi Peng1,2, Ming Zhao1–3 1Beijing Area Major Laboratory of Peptide and Small Molecular Drugs, Department of Medicinal Chemistry, School of Pharmaceutical Sciences, Capital Medical University, Beijing 100069, People’s Republic of China; 2Engineering Research Center of Endogenous Prophylactic of Ministry of Education of China, Department of Medicinal Chemistry, School of Pharmaceutical Sciences, Capital Medical University, Beijing 100069, People’s Republic of China; 3Department of Biomaterials, Beijing Laboratory of Biomedical Materials and Key Laboratory of Biomedical Materials of Natural Macromolecules, Beijing University of Chemical Technology, Beijing 100026, People’s Republic of ChinaCorrespondence: Ming ZhaoBeijing Area Major Laboratory of Peptide and Small Molecular Drugs, Department of Medicinal Chemistry, School of Pharmaceutical Sciences, Capital Medical University, No. 10, Youanmenwaixitoutiao, Fengtai District, Beijing 100069, People’s Republic of ChinaTel +86 108 391 1535Email mingzhao@bjmu.edu.cnBackground: Gemcitabine has been widely used as a chemotherapeutic drug. However, drug resistance, short half-life and side effects seriously decrease its chemotherapeutic efficacy.Purpose: The object of preparing RGDV-gemcitabine was to prolong the half-life, to overcome drug resistance and to eliminate bone marrow toxicity of gemcitabine.Methods: Arg-Gly-Asp-Val was coupled with gemcitabine, forming 4-(Arg-Gly-Asp-Val-amino)-1-[3,3-difluoro-4-hydroxy-5-(hydroxylmethyl)oxo-lan-2-yl]pyrimidin-2-one (RGDV-gemcitabine) involving 9-step reactions. The advantages of RGDV-gemcitabine to gemcitabine were demonstrated by a series of assays, such as in vitro half-life assay, in vitro drug resistance assay, in vivo anti-tumor assay, in vivo kidney toxicity assay, in vivo liver toxicity assay and in vivo marrow toxicity assay. The nano-features of RGDV-gemcitabine were visualized by TEM, SEM and AFM images. The tumor-targeting action and release of RGDV-gemcitabine were evidenced by FT-MS spectra.Results: Half-life and anti-tumor activity of RGDV-gemcitabine were 17-fold longer and 10-fold higher than that of gemcitabine, respectively. RGDV-gemcitabine, but not gemcitabine, showed no kidney toxicity, no liver toxicity, no marrow toxicity and no drug resistance. The advantages attributed to the nanofeatures of RGDV-gemcitabine were targeting tumor tissue and releasing gemcitabine in tumor tissue.Conclusion: RGDV-gemcitabine successively overcame the defects of gemcitabine and provided a practical strategy of nano-medicine.Keywords: gemcitabine, modification, half-life, anti-tumor, tumor targeting, release, toxicity, nano-species

Therapy strategy toward epidermal growth factor receptor (EGFR) inhibition in cervical cancer has been ongoing. EGFR promoter methylation status and EGFR tyrosine kinase inhibitor-sensitive mutations in cervical cancer may be significant for clinical outcome prediction using anti-EGFR treatment. In this study, EGFR tyrosine kinase inhibitor-sensitive mutations, EGFR exons 18, 19, and 21 mutations, were detected by sequencing in a total of 293 Chinese cervical squamous cell carcinoma tissue samples. EGFR promoter methylation status was detected by an EGFR asymmetric PCR and hybridization-fluorescence polarization assay and sequencing in 293 Chinese cervical squamous cell carcinoma tissue samples. High-risk human papillomavirus (HPV) genotypes in 293 Chinese cervical squamous cell carcinoma tissue samples were detected by an asymmetric GP5+/6+ PCR and hybridization-fluorescence polarization assay. No EGFR exons 18, 19, and 21 mutations were detected, EGFR promoter methylation status was identified in 98 samples, and HPV 16 infection was the first frequent HPV genotype. The methylated EGFR promoter was identified most frequently in cervical squamous cell carcinoma samples with HPV 16 infection (53.4%). Statistical significant difference of EGFR promoter methylation prevalence was found between HPV 16 and other HPV genotypes (P

(1) Background: Though X-ray excited photodynamic therapy (X-PDT) breakthrough the bottom neck of PDT application in deep tumor by overcoming light penetration depth limitation, the quantum yield of the hydrophilic X-PDT nanoparticles (NPs) still hampered its further application in vivo. Thus, establishing a proper hydrophilic decoration method which can maximally maintain the quantum yield of X-ray excited luminescent NPs is of urgent demand. (2) Methods: We synthesized NaGdF4: [Formula: see text] (NGF) as X-ray excited luminescent NPs and conducted hydrophilic decoration by two hydrophilic ligands, polyethylene glycol-NH2 (PEG) and cysteamine (Cy) via place exchange reaction, and coupled with photosensitizer (MC540) to form a X-PDT nanosystem. We also conducted experiments in vitro and in vivo to evaluate the efficacy of the X-PDT system. (3) Results: Both PEG and Cy decoration NPs presented excellent emission intensity, which could well excite the coupled photosensitizer MC540 to generate significant X-PDT efficacy under low-dose X-ray radiation. Especially for the NGF-Cy-MC540 treatment group, the cell viability reduced to [Formula: see text]% under 0.3[Formula: see text]Gy radiation and [Formula: see text]% under only 0.1[Formula: see text]Gy radiation, which is the lowest radiation dosage in the literature reports so far. In vivo experiment showed about 36% of tumor inhibition rate under 0.3[Formula: see text]Gy X-ray. Besides, no biotoxicity was observed in NGF groups even in high concentrations, demonstrating good biocompatibility. (4) Conclusions: The hydrophilic decoration method by Cy or PEG via place exchange reaction may pave a brand new way and strategy for X-PDT further clinical application.

In this study, the cyclic behaviors of low rise concrete shear walls using recycled coarse or fine aggregates were investigated. Eight low rise Recycled Aggregates Concrete (RAC) shear wall specimens were designed and tested under a cyclic loading. The following parameters were varied: replacement percentages of recycled coarse or fine aggregates, reinforcement ratio, axial force ratio and X-shaped rebars brace. The failure characteristics, hysteretic behavior, strength and deformation capacity, strain characteristics and stiffness were studied. Test results showed that the using of the Recycled Coarse Aggregates (RCA) and its replacement ratio had almost no influence on the mechanical behavior of the shear wall; however, the using of Recycled Fine Aggregates (RFA) had a certain influence on the ductility of the shear wall. When the reinforcement ratio increased, the strength and ductility also increased. By increasing the axial force ratio, the strength increased but the ductility decreased significantly. The encased brace had a significant effect on enhancing the RAC shear walls. The experimental maximum strengths were evaluated with existing design codes, it was indicated that the strength evaluation of the low rise RAC shear walls can follow the existing design codes of the conventional concrete shear walls.

In order to quantitatively evaluate the shear-bearing capacity of shear connectors of square concrete filled steel tube (CFST), push-out tests on 14 square CFSTs with shear connectors have been carried out. Among the 14 CFSTs, there are 13 specimens with steel plate connectors and one specimen with steel bar connectors. The following factors are investigated to figure out their influences on the performance of CFSTs, which are the width to thickness ratio of steel tube, thickness of steel plate, length of steel plate, strength of concrete, welding condition of steel plate, number of steel plate layer and interlayer spacing. The test results show that the ultimate bearing capacity and the elastic stiffness increase with decreasing width to thickness ratio of the steel tube, and increasing thickness and length of the steel plate. With increasing concrete strength, the ultimate bearing capacity also increases. However, the welding condition has no effect on the ultimate bearing capacity. The ultimate bearing capacity of the CFST with double-layer steel plate is greater than that with single-layer steel plate. The ultimate bearing capacity of steel bar type shear connector is 87% greater than that of the steel plate type shear connector, and the steel bar specimen shows good ductility. A formula for calculating the shear-bearing capacity of shear connectors has been developed, and the calculated shear-bearing capacities are in good agreement with the test data.

The seismic performance of recycled aggregate concrete (RAC) composite shear walls with different expandable polystyrene (EPS) configurations was investigated. Six concrete shear walls were designed and tested under cyclic loading to evaluate the effect of fine RAC in designing earthquake-resistant structures. Three of the six specimens were used to construct mid-rise walls with a shear-span ratio of 1.5, and the other three specimens were used to construct low-rise walls with a shear-span ratio of 0.8. The mid-rise and low-rise shear walls consisted of an ordinary recycled concrete shear wall, a composite wall with fine aggregate concrete (FAC) protective layer (EPS modules as the external insulation layer), and a composite wall with sandwiched EPS modules as the insulation layer. Several parameters obtained from the experimental results were compared and analyzed, including the load-bearing capacity, stiffness, ductility, energy dissipation, and failure characteristics of the specimens. The calculation formula of load-bearing capacity was obtained by considering the effect of FAC on composite shear walls as the protective layer. The damage process of the specimen was simulated using the ABAQUS Software, and the results agreed quite well with those obtained from the experiments. The results show that the seismic resistance behavior of the EPS module composite for shear walls performed better than ordinary recycled concrete for shear walls. Shear walls with sandwiched EPS modules had a better seismic performance than those with EPS modules lying outside. Although the FAC protective layer slightly improved the seismic performance of the structure, it undoubtedly slowed down the speed of crack formation and the stiffness degradation of the walls.

Brief electrical stimulation has been shown to be effective in promoting neuronal regeneration following peripheral nerve injury. These effects are thought to be mediated largely by the upregulation of the expression of brain-derived neurotrophic factor (BDNF) in spinal cord neurons. However, the molecular mechanisms by which electrical stimulation can promote BDNF expression are not known. The mechanism involved in BDNF expression after electrical stimulation was explored in this study. Immunohistochemistry and Western blotting were used to test BDNF expression. Confocal microscopy was utilized to study intracellular Ca(2+) volume. Immunohistochemistry and Western blotting confirmed that brief electrical stimulation increased BDNF expression in spinal cord neurons both in vivo and in vitro. Treatment of cultured neurons with nifedipine, an inhibitor of voltage-gated calcium channels, significantly reduced the BDNF increase produced by electrical stimulation, and an inhibitor of Erk completely abolished the effect of electrical stimulation. Levels of BDNF expression in the presence of the Erk inhibitor were lower that in unstimulated and untreated controls, indicating that Erk activation is required to maintain baseline levels of BDNF. Confocal microscopy using a Ca(2+)-sensitive fluorochrome revealed that electrical stimulation is accompanied by an increase in intracellular Ca(2+) levels; the increase was partly blocked by nifedipine. These findings argue that electrical stimulation increases BDNF expression in spinal cord neurons by activating a Ca(2+)- and Erk-dependent signaling pathways.

Excision repair cross-complementing 1-118 single nucleotide polymorphisms (SNPs) have been reported as predictive markers of response to platinum-based chemotherapy. Currently, the most used methods for genotyping of SNPs are costly and time consuming. It is necessary to develop a method that is more accurate, cost-effective, and simple. An improved fluorescence polarization assay based on asymmetric polymerase chain reaction hybridization for screening excision repair cross-complementing 1-118 SNPs has been developed. Excision repair cross-complementing 1-118 SNPs of all 907 samples were analyzed in sequence and improved fluorescence polarization assay in parallel. The sensitivity, specificity, and stability of the improved fluorescence polarization assay were measured. This study showed the accuracy, simplicity, and cost-effectiveness of the fluorescence polarization assay in the detection of excision repair cross-complementing 1-118 SNPs in a panel of 907 samples. The fluorescence polarization assay was more accurate for the heterozygous sample than was the sequence assay. The minimum detection level established with the fluorescence polarization assay was 2.5 genome copies per reaction and no cross-reaction was observed.