Search

Size-controlled and high-index faceted α-Fe 2 O 3 nanocrystals with pseudocubic and rhombohedral morphologies were synthesized through the hydrothermal treatment of β-FeOOH at different pHs. The size effect on the photocatalytic oxygen evolution efficiency of high-index faceted α-Fe 2 O 3 nanocrystals was investigated. Rhombohedral α-Fe 2 O 3 (pH 6.0) exhibits an outstanding apparent quantum yield of 9.93% and an oxygen evolution efficiency of 20.3%, which can be attributed to the optimal size and high-indexed {104} planes. This work provides a new idea for the design of high activity water oxidation catalysts, through the size optimization of high-index faceted materials., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

Unlike the probe wavelength, which is spectrally resolved by monochromator, the excitation wavelength in two-dimensional electronic spectroscopy is retrieved by means of Fourier transform of the interference signal introduced by the coherence delay time between the first and second excitation laser pulses. Hence, the calibration of delay lines would determine its accuracy. In this work, we showed that an inaccurate calibration factor of wedge-based delay line would result in a global peak shift and asymmetric spectral twists along the excitation axis. Both theoretical analysis and experiments have shown that such spectral distortions can be corrected by an accurately predetermined calibration factor. The relative accuracy of calibration factor reaches 3 × 10 -5 in our setup. The dispersion effect of wedges also has been considered for the broadband excitation.

The features of the electronic structure of semiconductor photocatalysts are fundamental to understanding the corresponding photocatalytic process. Besides the bandgap and edges, the behavior of photogenerated charge carriers and trap states can also greatly affect the photocatalytic process but it has been less considered during the material design. A previous study (G. Liu, J. Pan, L. Yin et al., Adv. Funct. Mater., 2012, 22, 3233-3238) showed that the interstitial boron on anatase {001} facets can change the photocatalytic preference from reductive H2 evolution to oxidative O2 evolution in the water splitting reaction, interpreted as the change in the band edges. In this work, we employed transient infrared absorption-excitation energy scanning spectroscopy and femtosecond time-resolved mid-infrared spectroscopy to investigate this phenomenon in view of the effect caused by the boron dopant on the photogenerated carrier kinetics and the energy level distribution of the trap states. We found that the surface boron doping eliminates significantly the trap states above the valence band, which improves its photocatalytic oxygen generation. On the other hand, surface boron doping also introduces a substantial amount of electron recombination centers (i.e., Bσ+ in the shell layer). Furthermore, surface boron doping also leads to an inefficient electron transfer from TiO2 to the co-catalyst Pt. Both of these effects give rise to its inferior photocatalytic capability in H2 evolution.

Native buckwheat, a common component of food products and medicine, has been observed to inhibit cancer cell proliferation in vitro. The aim of the present study was to evaluate the in vitro and in vivo anti-tumoral effects of recombinant buckwheat trypsin inhibitor (rBTI) on hepatic cancer cells and the mechanism of apoptosis involved. Apoptosis in the H22 cell line induced by rBTI was identified using MTT assays, DNA electrophoresis, flow cytometry, morphological observation of the nuclei, measurement of cytochrome C and assessment of caspase activation. It was identified that rBTI decreases cell viability by inducing apoptosis, as evidenced by the formation of apoptotic bodies and DNA fragmentation. rBTI-induced apoptosis occurred in association with mitochondrial dysfunction, leading to the release of cytochrome C from the mitochondria to the cytosol, as well as the activation of caspase-3, -8 and -9. In conclusion, the results of the present study suggested that rBTI specifically inhibited the growth of the H22 hepatic carcinoma cell line in vitro and in vivo in a concentration-dependent and time-dependent manner, while there were minimal effects on the 7702 normal liver cell line. In addition, rBTI‑induced apoptosis in H22 cells was, at least in part, mediated by a mitochondrial pathway via caspase-9.

This study aims to construct a eukaryotic expression system for envelope gene of Jaagsiekte sheep retrovirus, observes its localization in 293T cells, and investigates the potential in inducing malignant transformation of NIH3T3 cells. By RT-PCR, the full-length cDNA of envelope gene of Jaagsiekte sheep retrovirus (exJSRV-env) was amplified from the extract of naturally infected sheep lung. The clone of target gene was sub-cloned into eukaryotic expression system pEGFP-C1, and validated by PCR, restriction endonuclease, and sequencing. Bioinformatic analysis concerning biological function and cellular localiza tion of exJSRV-env was also performed. The recombinant clone of exJSRV-env was transfected into 293T cells and NIH3T3 cells by Lipofectamine LTX. The expression and celluar localization in 293T cells were validated by confocal microscopy. Soft agar colony formation assay was employed to test the anchorage-independent growth of NIH3T3. DNA sequencing and restriction enzyme digestion with Kpn I and Hind III indicated the correct construction of the recombinant plasmid, which was named pEGFP-C1/exJSRV-env. Amino acid sequence alignment of exJSRV-env with reference sequences found 85%-100% homogeneity. A YRNM motif was discovered at the cytoplasmic tail of envelope gene, which is exclusively found in exogenous viruses. Phylogenetic tree analysis showed that our clone of exJSRV-env clustered closely with pathogenic exogenous Jaagsiekte sheep retroviruses. Fluorescence microscopy indicated typical membrane localization of exJSRV-env protein. NIH3T3 cells transfected with exJSRV-env lost contact inhibition, and acquired colony forming ability in soft agar. This study indicated that envelope protein of Jaagsiekte sheep retrovirus can induce malignant transformation of mouse fibroblast cell NIH3T3. Discoveries of this study provide a basis for further structural and functional research on Jaagsiekte sheep retrovirus envelope protein.

Background/aims: There are no satisfactory biomarkers for hepatocellular carcinoma (HCC). The surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) technique has been used to identify biomarkers for cancer., Methodology: Four hundred thirty five serum samples were tested by SELDI-TOF-MS matching on a gold chip. Samples were assigned to a training set and a testing set according to collection order. The training set was used to identify statistically significant peaks and to develop the artificial neural network (ANN) model for diagnosing HCC. The testing set was used in a blind test to validate the diagnostic efficiency of the ANN model., Results: A total of 75 proteins that differed between patients and controls were identified (p<0.05). Seven of these proteins (p<0.01; m/z at 4207Da, 6604Da, 7734Da, 8106Da, 8545Da, 8599Da, 8894Da) were chosen to develop the ANN model. The model was subjected to a blind test using the testing set for HCC diagnosis. Sensitivity and specificity were 84.00% and 81.25%, respectively, and the accuracy was 81.90%., Conclusions: These results suggest that patients with HCC may have serum proteins that differ from healthy controls. The ANN is a new method for diagnosing and identifying HCC.

To investigate the association between apolipo-protein E (APOE) polymorphisms and insulin resistance and Traditional Chinese Medicine (TCM) syndromes in type 2 diabetes mellitus (T2DM) with macroangiopathy, 60 patients with T2DM macroangiopathy were enrolled and divided into three groups: dryness-heat due to deficiency of yin, Qi-Yin deficiency, and Yin-Yang deficiency, according to the TCM syndromes, with a control group of 20 healthy individuals. APOE genotype analysis was performed with polymerase chain reaction amplification and restriction fragment length polymorphism, and the results showed that the proportion of the ε4/4 and ε3/4 genotypes and frequencies of the ε4 and ε3 alleles were higher in the Qi-Yin deficiency group (P<0.05). Among the T2DM macroangiopathy patients, the E4 group had the largest number of cases, as well as a significantly longer disease course compared to the E2 group (P<0.05). The insulin resistance index (IRI), insulin action index and body mass index (BMI) of patients in the Yin-Yang deficiency group were significantly different from those of patients with dryness-heat due to deficiency of yin and Qi-Yin deficiency. Furthermore, correlation analysis of the BMI and IRI of patients in the Yin-Yang deficiency group revealed a correlation coefficient r=0.696 (P<0.01) and a typical correlation between them. In conclusion, the Qi-Yin deficiency in T2DM patients with macroangiopathy is associated with the APOE E4 and E3 genotypes. Thus, the APOE gene polymorphism can, to some degree, reflect the TCM syndrome types of T2DM patients with macroangiopathy. Insulin resistance plays an important role in the occurrence of T2DM macroangiopathy and is closely associated with the Yin-Yang deficiency according to the TCM differentiating types.

Aim: To determine the most important region in tartary buckwheat allergen., Methods: The gene of epitopes was amplified by PCR using the primers designed according to TBa cDNA. Four expression vectors containing the gene of epitopes were constructed, and then transformed into the E.coli BL21(DE3) host cells. The expression products were purified by Ni(2+);-NTA agarose affinity chromatography column and indirect ELISA, inhibition ELISA and Dot blot was performed using sera from allergenic patients., Results: The purified proteins were obtained and the immunological results showed that E1 exhibite stronger IgE binding to patient's serum than the other epitopes., Conclusion: E1 is probably the most important region in tartary buckwheat allergen binding to buckwheat allergic sera IgE.

Aim: To prepare the rat antibody against the recombinant buckwheat trypsin inhibitor., Methods: The recombinant buckwheat trypsin inhibitor was expressed in E.coli. BL21 (DE3) and used as an immunogen to immunize the rat. The titer and specificity of the anti-BTI antibody from the rat were analyzed by ELISA, Western blot and immunohistochemistry, respectively., Results: ELISA detection indicated the titer of the antiserum was about 1:128 000. Western blot analysis showed the antibody reacted specifically with rBTI. The immunohistochemistry analysis proved that rBTI was expressed in the cytoplast and nucleus of EC9706 cells., Conclusion: The rat antibody against rBTI has high titer and specificity, which is beneficial to further study on the molecular mechanisms in rBTI-induced apoptosis of tumor cells and also provide an important theory basis for further exploring the relationship between the structure and function of BTI.

The study was purposed to investigate the apoptosis of HL-60 cells induced by recombinant common buckwheat trypsin inhibitor (rBTI) and its mechanism. The inhibition rate of rBTI on HL-60 cells was detected by MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide); the morphology of HL-60 nuclei was observed by fluorescence microscopy; the apoptosis cells of HL-60 detected by agarose gel electrophoresis and the changes of apoptosis rate was assayed by flow cytometry (FCM), when the HL-60 cells were treated with different concentration of rBTI for 24 hours. The results showed that the growth of HL-60 cells was inhibited evidently after treatment with rBTI in a dose-dependent manner, but there were minimal effects on normal human peripheral blood mononuclear cells (PBMNCs). The nuclei of HL-60 cells showed the characteristics of apoptosis, the analysis by flow cytometry indicated that the apoptosis rate of HL-60 cells was 52% after treatment with rBTI (100 microg/ml), DNA analyzed by agarose gel electrophoresis showed "ladder" pattern. It is concluded that rBTI obviously inhibits growth of HL-60 and induces its apoptosis which provides a foundation for use of recombinant common buckwheat trypsin inhibitor to cure the acute myeloid leukemia.

A quinoidal thiophene molecule which is a prototype of the repeated unit of s-trans-cis-polyacetylene was studied by sub-5 fs spectroscopy. A breatherlike mode modulation of both the amplitude and frequency of the C[Double Bond]C stretching was observed for the first time. It generates two sidebands of 2238 and 700 cm(-1) with a separation of 769 cm(-1) corresponding to the modulation frequency. The latter mode is very close to the C-S-C ring deformation, which indicate that this mode mediates coupling between the breather mode and the C(beta)-C(beta) stretching mode. It was also found that the breather-type excitation has a longer lifetime (2-3 ps) than in all-trans-polyacetylene (50 fs) due to its confinement.

Aim: To investigate the radiation response of various human tumor cells and normal liver cells., Methods: Cell lines of human hepatoma cells (SMMC-7721), liver cells (L02), melanoma cells (A375) and cervical tumor (HeLa) were irradiated with (60)Co gamma-rays. Cell survive was documented by a colony assay. Chromatid breaks were measured by counting the number of chromatid breaks and isochromatid breaks immediately after prematurely chromosome condensed by Calyculin-A., Results: Linear quadratic survival curve was observed in all of four cell lines, and dose-dependent increase in radiation-induced chromatid and isochromatid breaks were observed in GB2B phase. Among these four cell lines, A375 was most sensitive to radiation, while, L02 had the lowest radiosensitivity. For normal liver cells, chromatid breaks were easy to be repaired, isochromatid breaks were difficult to be repaired., Conclusion: The results suggest that the gamma-rays induced chromatid breaks can be possibly used as a good predictor of radiosensitivity, also, unrejoined isochromatid breaks probably tightly related with cell cancerization.

In the present research, suppression subtractive hybridization (SSH) and high density membrane techniques were employed to analysis genes induced by water stress in wheat seedling at 2-leaf stage. The purpose was to comprehensively understand the genetic bases of drought resistance and to find the key genes related to drought resistance in wheat. A total of 181 positive clones were obtained by screening the SSH library including 1 530 individual recombinant clones. The result of the sequence homologous comparison and function querying showed that 83.2% differentially expressed genes were high homologous with those induced by abiotic or biotic stresses in plant and their functions were to protect the cell directly or indirectly from stress strain. Seventeen differentially expressed ESTs found first were registered in GenBank. After further identifying by reverse Northern, RT-PCR and Northern, the gene expression profile induced by water stress in wheat seedling was preliminarily revealed.