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Two new Keggin-based organic-inorganic hybrid compounds, namely [Cu8(H2biim)8(SiW12O40)2] ·7H2O ( 1) and [Cu2(H2biim)4(H2O)2(SiMo12O40)] ( 2) (H2biim = 2,2′-biimidazole), were hydrothermally synthesized by using the bi-imidazole ligand and Keggin anions, and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectra, and cyclic voltammetry. In compound 1, two H2biim ligands are fused by two Cu+ ions to form a dinuclear [Cu2(H2biim)2]4+ subunit. The Cu3-based dinuclear subunits are further connected by [SiW12O40]4- anions to construct a 1D chain. The other Cu1-based dimer acts as a supporting unit of the anion. Through changing [SiW12O40]4- to [SiMo12O40]4-, compound 2 was obtained, including discrete anions and mononuclear subunits [Cu(H2biim)2(H2O)]2+. The electrochemical behaviors of compounds 1 and 2 bulk-modified carbon paste electrodes ( 1- and 2-CPE) were studied. [ABSTRACT FROM AUTHOR]

Distinct corrosion behavior was reported in multiphased titanium alloys prepared by additive manufacturing and by traditional technologies because of different phase constituents formed during processing. An open question is therefore raised: is there always different corrosion behavior of materials prepared by different methods? This work reports resemble corrosion behavior of selective laser melted and wrought single β-phase Ti-24Nb-4Zr-8Sn (Ti2448) in both NaCl solution and Hank's solution. The electrochemical measurements showed that both samples have close calculated polarization resistance and corrosion potential in NaCl solution, i.e., 4.99 ± 0.63 MΩ cm 2 and -0.26 ± 0.01 V for the selective laser-melted Ti2448, and 4.42 ± 0.71 MΩ cm 2 and -0.25 ± 0.01 V for the wrought Ti2448, respectively. Both samples reveal the same variation in weight change after 180-day immersion test in Hank's solution. Such resemblance in corrosion behavior without pitting morphologies is attributed to the formation of monolithic β-phase during processing, which demonstrates that titanium alloys with single phase show comparable corrosion behavior regardless of the manufacturing methods adopted.

Objective: To monitor the 3-dimensional (3D) morphological changes of C6/36 cells during dengue virus (DENV) infection using a live-cell imaging technique based on digital holographic microscopy and provide clues for better understanding the mechanisms of DENV infection., Methods: C6/36 cells were seeded in 6-well plates to determine the optimal imaging density under a holographic cell imager, and the morphological changes of the cells were recorded in response to a culture temperature change from 28 degrees celsius; to 37 degrees celsius; C6/36 cells were infected with 4 DENV strains with different serotypes at 28 degrees celsius; and incubated at 37 degrees celsius; for 24 h, and the 3D holograms and relevant morphological parameters were recorded at different time points using HoloMonitor M4 holographic cell imaging and analysis system., Results: The holograms of C6/36 cells inoculated at the optimal density for imaging (4×10 5 per well) showed unified 3D morphologies of the single cells with minimal dispersions in the cell area, thickness and volume (P<0.05), which did not undergo obvious changes when the cells were incubated at 37 degrees celsius; for 24 h (P>0.05). The cell area and volume of the cells infected with the 4 DENV strains all increased and the cell thickness was reduced during incubation. Among the 4 strains, DENV-1 and DENV-2 caused reduced cell thickness while DENV-3 and DENV-4 increased the cell thickness, and the pattern and degree of such changes differ among the 4 strains., Conclusions: Digital holographic microscopy allows monitoring of the complex morphological changes of cells during DENV infection. The 4 DENV strains with different serotypes causes characteristic cell damages during infection.

DNA barcoding is an effective technique in species identification. To determine the candidate sequences which can be used as DNA barcode to identify in Papaver genus, five potential sequences (ITS, matK, psbA-trnH, rbcL, trnL-trnF) were screened. 69 sequences were downloaded from Genbank, including 21 ITS sequences, 10 matK sequences, 8 psbA-trnH sequences, 14 rbcL sequences and 16 trnL-trnF sequences. Mega 6.0 was used to analysis the comparison of sequences. By the methods of calculating the distances in intraspecific and interspecific divergences, evaluating DNA barcoding gap and constructing NJ and UPMGA phylogenetic trees. The sequence trnL-trnF performed best. In conclusion, trnL-trnF can be considered as a novel DNA barcode in Papaver genus, other four sequences can be as combination barcode for identification.

To discuss the pathogenesis of Alzheimer's disease (AD), we summarized the mechanisms of treating AD animal models by acupuncture from literatures in recent years as follows. Senile dementia rats' cognitive capabilities and memory could be improved by reduction of beta-amyloid protein, attenuation of excessive phosphorylation of tau protein, regulation of center neurotransmitter dysmetabolism, oxidation of anti-free radicals, reduction of neuron apoptosis in the cortex and the hippocampus, inhibition of glial cells' differentiation, adjustment of G protein signaling transduction, and improvement of the mitochondrial dysfunction, thus providing experimental evidence for treating AD by acupuncture.

Objective: To identify the differentially expressed microRNAs in the hippocampus of Down Syndrome model mouse Ts65Dn., Methods: Low molecular weight RNA from hippocampus were tailed and reverse transcribed by extended RT-primer. MicroRNAs primers were arrayed on plates according to the Tm of each primer. PCR were carried out at different annealing temperatures using a gradient real-time PCR instrument. The relative expression level of each microRNAs was calculated using the most stable reference gene as normalizer which was selected by geNorm and Normfinder software., Results: miR-27a was identified as the most stable reference gene by geNorm and Normfinder software. Among the 52 microRNAs detected by real-time PCR array, miR-33 and miR-19a were significantly down-regulated, whereas miR-130 were significantly up-regulated in the hippocampus of Ts65Dn mice as compared with the euploid control mice. The expression of miR-802, which was the trisomy chromosome 16 derived microRNAs, was very low in hippocampus with no difference between the two groups., Conclusion: MicroRNAs are dysregulated in the hippocampus of Ts65Dn mice, which may contribute to the reduced neurogenesis of Down syndrome.

Objective: To investigate the non-specific and inaccurate amplification in cases of highly similar sequences among family members and the length heterogeneity of mature microRNA (miRNA), and find a condition that discriminates maximally among similar miRNA family members and detects the accurate expression level of miRNAs., Methods: Primers with their mismatches and/or 3' end at different positions were designed. Amplification efficiencies were compared using matched and various mismatched primers by RNA-tailing and primer-extension RT-PCR at different annealing temperatures. Expression levels of several miRNAs in mouse brain were compared using miRNA specific primers with different termini., Results: Raising annealing temperatures 12 degrees Celsius-14 degrees Celsius above the T(m) of the primers maximally increased amplification specificity without sacrificing sensitivity. Primers designed with their termini on or near variant positions could efficiently discriminate between miRNA isoforms. Using primers that terminated before the end of the mature miRNA did not miss the detection of shorter mature miRNA and provided accurate expression levels., Conclusion: Careful primer design and higher annealing temperature can increase specificity and accuracy of real time PCR miRNA detection.

Objective: To examine global expression levels of microRNAs(miRNAs) in mouse cerebrum and to provide an important basis for detailed studies of individual miRNAs, their target genes, the miRNA-related regulatory networks in the mammalian central nervous system, and their implications in diseases., Methods: Low molecular weight RNA from cerebrum of five C57BL/6J mice were tailed and reverse transcribed by extended RT-primer. miRNA primers were carefully designed and arrayed on plates according to the Tm of each primer. PCR was carried out at different annealing temperatures using a gradient real-time PCR instrument. The relative expression level of each miRNA was calculated using 5sRNA for normalization., Results: Among the 285 miRNAs detected, 260 were positive with varying abundance. Their frequency distribution was approximately a normal distribution. The expression levels of most miRNAs were in accordance with previously published results by microarray. However, the positive rate was higher than that detected by microarray. miRNAs originating from the same hairpin precursors expressed at similar or significantly different levels. Clusters of proximal miRNAs were similar or quite different in abundance. It is suggested that the fate of miRNA after transcription determined their abundance., Conclusion: Using the RNA-tailing and primer-extension PCR array method, we obtained expression profile of miRNA in mouse cerebrum, especially the relative expression data of many low abundant miRNA in mouse cerebrum, which will be of special help for studying the fine-tuning function of low-level miRNAs.

Objective: To study the association between the functional polymorphism of matrix metalloproteinases (MMPs) and the development of chronic obstructive pulmonary disease (COPD)., Methods: 147 COPD patients and 120 healthy smoking controls were selected. Spirometry and chest X-rays had been taken. Questionnaires including sex, age, smoking history, occupational exposure were completed. MMP-9 (-1562 C/T), MMP-1(-1607 1G/2G), MMP-12 (-82 A/G), MMP-12(-357 Asn/ Ser) alleles were determined using PCR-RFLP method. Independent samples T test analysis was carried out to compare patients' age, smoking index, FEV1 /FVC, FEV1 % pred with that of healthy controlled group. The frequencies of genotypes and alleles between groups were analyzed by chi-square tests and multilogistic regression., Results: MMP12 Asn/Asn, CT/AsnAsn were risk factors for smoking-induced COPD. The ORs were 2.361 (95% CI: 1.369-4.017) and 2.433(95% CI: 1.159-5.342) respectively while CC/1G1G/ SerSer seemed to be a protective factor for smoking-induced COPD, with OR as 0.457 and 95% CI as 0.231-0.911., Conclusion: Asn/Asn, CT/AsnAsn might be susceptible genotypes while CC/GG/SerSer might serve as protective genotype.

Objective: To study the immunotherapeutic effect on the esophageal adenocarcinoma mediated by gp96-peptide complexes isolated from the same kind of tumor., Methods: gp96-peptide complexes were purified from nude mice tumors burdened by subcutaneous injection of human esophageal adenocarcinoma cell line SEG-1. gp96-peptide complexes were carried by the dendritic cells(DC) induced from human peripheral blood mononuclear cells to prepare gp96-DC vaccine. The proliferation of lymphocytes was tested with trypan-blue stain. The quantity of interferon-gamma(IFN-gamma) released from cytotoxic T lymphocytes (CTL) was detected with ELISA method. The killing effect of CTL on target cell SEG-1 was measured with MTT., Results: We obtained 120 microg gp96 from 55 g tumor tissue. DC, gp96, and gp96-DC all could elicit the proliferation of lymphocytes and make them becoming into CTL which released IFN-gamma and showed different degrees of killing effect on target cell SEG-1. gp96-DC has the strongest eliciting effect among them. At the ratio of E(effect) to T(target) as 40:1,the killing rate was 68%. No significant difference between the effects of CTL induced by DC alone and of lymphocytes without specific antigen on SEG-1 and K562 cells., Conclusion: The gp96-peptide complexes from tumors can improve the effect of eliciting lymphocyte proliferation of DC and make the lymphocyte becoming into CTL more effectively. These CTLs show prominent killing effect on the target tumor cells.

Objective: To further study the effect of apoptin in inducing cancer cell specific apoptosis and the possible applications in cancer therapy., Methods: Apoptin gene was amplified by PCR and inserted into pcDNA3.1(+) with a FLAG tag in front of the multi-cloning-site. Apoptin gene with the FLAG tag was sub-cloned into an adenovirus vector. Several cancer cell lines were transfected with pcDNA3.1/FLAG/apoptin or infected with apoptin containing recombinant adenoviruses to study the morphologic changes. Ad/apoptin infected cells were also analyzed by flowcytometry after staining with PI., Results: Expressed apoptin was localized in the nucleus of cancer cells. Chromatin condensation occurred 2 or 3 days after Ad/apoptin(+) infection. Cell number in G(2)-M phase increased dramatically after Ad/apoptin(+) infection., Conclusion: Apoptin can induce cell cycle G(2)-M arrest and chromatin condensation in cancer cells.