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Metal-Organic Frameworks (MOFs) are a kind of porous crystalline compounds, which are self-assembled by metal clusters and organic ligands through coordination bonds. UiO66 is a kind of MOF crystal materials with a porous octahedral structure, which is coordinated by zirconium ion and terephthalic acid (H2BDC). In this paper, UiO66-NH2 and UiO66-(COOH)2 were prepared, and UiO66-NH2 was modified by Post-Synthetic Modification (PSM) to obtain UiO66-NH2-COOH material. The prepared samples and intermediate products were characterized by infrared spectrum (IR). UiO66-NH2-COOH and UiO66-(COOH)2 materials were loaded with horseradish peroxidase (HRP), which catalyzed the reaction between H2O2 and 3, 3', 5, 5'-tetramethylbenzidine (TMB). Via the results of UV-vis spectrophotometry measurement, it was found that UiO66-(COOH)2 loaded with HRP had better catalytic effects than only HRP. In order to verify the influence of carboxyl groups on UiO66-NH2-COOH and UiO66-(COOH)2 materials, the adsorption of rhodamine B (RhB) was studied in this paper. The results of fluorescence spectrophotometer showed that UiO66-NH2-COOH material had better adsorption effect on RhB than UiO66-(COOH)2 material, which may be attributed to the flexibility of UiO66-NH2-COOH material after PSM. UiO66-NH2-COOH and UiO66-(COOH)2 materials were characterized by X-ray powder diffraction (XRD) before and after adsorption of RhB. The XRD pattern of UiO66-(COOH)2 material has no obvious characteristic peak, which indicates that it belongs to nanoparticle polymer. The results are consistent with the UV-visible results, and the nanoparticle polymer has better catalytic effects.

A self-assembled functionalized metal-organic framework, Dy-NH2-BDC, was prepared by washing Dy-NH2-BDC complex with DMF and CH2Cl2. Via the post-synthetic modification (PSM) of heterobifunctionali...

Single-walled metal-organic nanotubes (SWMONTs) could be dried in vacuum to obtain SWMONTs with activation sites. Glycine and diethylenetriamine (2,3-NH2) were added to activated SWMONTs, and SWMON...

A self-assembled functionalized metal-organic framework, Zn4O(NH2BDC)3 microcrystalline (IRMOF3) could be prepared by washing complex with DMF and CH2Cl2. Via modification with sodium alginate (AA)...

Infectious bursal disease virus (IBDV) infection causes pathogenicity and mortality in chickens, leading to huge economic losses in the poultry industry worldwide. Studies of host-virus interaction can help us to better understand the viral pathogenicity. As a highly conservative host factor, heat shock protein 70 (Hsp70) is observed to be involved in numerous viral infections. However, there is little information about the role of chicken Hsp70 (cHsp70) in IBDV infection. In the present study, the increased expression of cHsp70 was observed during IBDV-infected DF-1 cells. Further studies revealed that Hsp70 had similar locations with the viral double-stranded RNA (dsRNA), and the result of pull-down assay showed the direct interaction between cHsp70 with dsRNA, viral proteins (vp)2 and 3, indicating that maybe cHsp70 participates in the formation of the replication and transcription complex. Furthermore, overexpression of cHsp70 promoted IBDV production and knockdown of cHsp70 using small interfering RNAs (siRNA) and reducedviral production, implying the necessity of cHsp70 in IBDV infection. These results reveal that cHsp70 is essential for IBDV infection in DF-1 cells, suggesting that targeting cHsp70 may be applied as an antiviral strategy.

Malignant melanoma, an increasingly common form of skin cancer, poses a significant threat to public health, especially when the disease progresses past skin lesions to the stage of advanced metastasis. In this work, a new anti-tumor peptide, temporin La (T-La), was selected from a cDNA library generated from bullfrog skin. Two new derivative antitumor peptides, T-La (S) and T-La (FS), were designed by bioinformatics analysis and coupled with the RGD small molecule peptide to create chimeric RGD peptides, (RGD-T-La [S] and RGD-T-La [FS]). Preliminary experiments showed that the new antitumor peptides had significant antitumor effects. After coupling to the chimeric RGD peptide, the targeted treatment of mouse melanoma was significantly improved. Our data demonstrate that the 4 peptides tested herein significantly inhibited the proliferation, migration, and invasion of B16F10 cells; with an increase in polypeptide concentration, the proportion of melanoma cells in the G0/G1 phase decreased or increased significantly, respectively, the reactive oxygen species (ROS) content increased significantly, the mitochondrial membrane potential decreased significantly, and the expression of pro-apoptotic Bax, Caspase-3, and Caspase-9 increased, and anti-apoptotic Bcl-2 decreased significantly. Tyr and MITF genes were significantly downregulated. In conclusion, the use of these new anti-tumor peptides, when combined with a chimeric RGD peptide, may increase ROS levels and decrease mitochondrial membrane potential by inhibiting the activity of mitochondria, thus releasing apoptosis-promoting factors in B16F10 cells. The present study describes a new potential strategy for the application of promising peptides in the treatment of various cancers.

Melanoma is a common malignant skin tumor, which is the only fatal skin tumor at present. Melanoma has a high degree of malignancy and metastasis. The activity of modified Temporin-La (T-La) peptides from bullfrog skin were evaluated for antitumor activity and improved targeting in melanoma cells. The amino acid sequence of T-La was modified, resulting in the antitumor peptide, T-La (FS). T-La and T-La (FS) were coupled to the RGD small molecule polypeptide to form the chimeric peptides RGD-T-La and RGD-T-La (FS), respectively. The secondary structures for the peptides, evaluated using circular dichroism, were found to be α-helical. The structure of T-La was evaluated using bioinformatics. In addition, the antitumor effects of the modified peptide and the targeting of RGD chimeric peptide to the tumor in vivo and in vitro were analyzed. Antitumor activity was measured in vitro using the MTT assay. Tumor cells with high integrin αvβ3 expression were detected using flow cytometry, and tumor cells were screened for sensitivity to RGD-T-La (FS) to establish a tumor model in nude mice. The effects of the peptides on tumor cells were measured using laser confocal microscopy in real-time. The mechanism of the peptide antitumor activity in tumor cells was evaluated with scanning electron microscopy. B16 melanoma cells were the most sensitive to the peptides, for which the cell survival rate was 24.65% for 10 µg/ml RGD-T-La (FS). RGD-La (FS) had a rapid effect on tumor cells. RGD chimeric polypeptides exhibited site-targeting cytotoxic effects in tumor cells. In the B16 melanoma mouse model, the peptides exhibited antitumor effects against early melanoma development and induced tumor apoptosis, possibly by inhibiting VEGF and promoting caspase-3 expression. Overall, the present study provides a scientific basis for the application of small molecule antimicrobial peptides as targeted antitumor agents and lays the foundation for the clinical application of these peptides as antitumor drugs.

A novel filtering algorithm is proposed based on level set method (LSM) and linear time Euclidean distance transform (LET) algorithm in this paper, which has the property of shape retention and thus is suitable for post-processing of the initial contours for contacting instances in digital Pap image. As one of our contributions, we propose two new metrics based on the pixel-level average false positive rate and false negative rate that used by baseline method. A significant decrease in pixel-level average false positive rate (FP) by 62% can obtain by our proposed method. The result of quantitative and qualitative evaluation shows that our proposed shape retentive filtering algorithm (SRFA) can effectively filter out the false positive fragments of the initial instance contour of cervical cells from the ISBI-2014 dataset.

Six binuclear rare earth compounds were synthesized through the ligand of 4-Bromo-N-hydroxy-N-methyl-benzamide (sH2bha). Compounds 1–3 are isomorphous, and compound 1 is crystallized in the monoclinic system with the P21/c space group. Compounds 4 and 5 are isomorphous, and compound 4 is crystallized in the triclinic system with the P-1 space group. Compound 6 is crystallized in the triclinic system with the P-1 space group. The compounds were characterized by thermogravimetric analysis (TGA) and IR spectroscopy. The fluorescence spectrum in the visible area shows characteristic peaks of Eu, Tb, and Dy compounds. The efficiency of Eu compound on the viability of PC3 cells was assessed using CCK8 assays. From the CCK8 results, ionic concentration may have a great effect on PC3 cells' proliferation. Eu compound shows red fluorescence in the cytoplasm of PC3 cell. As for Eu compound, it might have potential application in cell imaging technology.

Doxorubicin (DOX) is a member of the anthracycline class of chemotherapeutic agents that are used for the treatment of many common human cancers. A self-assembled functionalized metal-organic nanotubes, SWMONTs could be loaded with the anticancer drug DOX. Via the modification of SWMONTs, DOX/SWMONTs-SiO 2 , DOX/SWMONTs-SiO 2 -NH 2 , DOX/SWMONTs-SiO 2 -NH 2 -FA samples could be obtained. The SEM characterization of the samples indicated that the particle size of DOX/SWMONTs-SiO 2 NH 2 samples were smaller than 200 nm. Drug-release experiments implied that DOX from the DOX/SWMONTs-SiO 2 -NH 2 -FA samples could be released faster at acidic tumor tissue than at normal body fluid (pH7.4). DOX has strong cytotoxicity, and at 20 μg/mL dosage of DOX large amount of apoptotic cells could be seen. Cellular uptaking experiments were used to study the apoptotic mechanism, while for DOX/SWMONTs-SiO 2 -NH 2 -FA samples, the strong drug fluorescence was found in the cytoplasm rather than in the nucleus.

Development of an accurate and automated algorithm to completely segment cervical cells in Pap images is still one of the most challenging tasks. The main reasons are the presence of overlapping cells and the lack of guiding mechanism for the convergence of ill-defined contours to the actual cytoplasm boundaries. In this paper, we propose a novel method to address these problems based on level set method (LSM). Firstly, we proposed a morphological scaling-based topology filter (MSTF) and derived a new mathematical toolbox about vector calculus for evolution of level set function (LSF). Secondly, we combine MSTF and the mathematical toolbox into a multifunctional filtering algorithm 2D codimension two-object level set method (DCTLSM) to split touching cells. The DCTLSM can morphologically scale up and down the contour while keeping part of the contour points fixed. Thirdly, we design a contour scanning strategy as the evolution method of LSF to segment overlapping cells. In this strategy, a cutting line can be detected by morphologically scaling the union LSF of the pairs of cells. Then, we used this cutting line to construct a velocity field with an effective guiding mechanism for attracting and repelling LSF. The performance of the proposed algorithm was evaluated quantitatively and qualitatively on the ISBI-2014 dataset. The experimental results demonstrated that the proposed method is capable of fully segmenting cervical cells with superior segmentation accuracy compared with recent peer works.

In this work, we present novel kinds of γ-Fe2O3@SiO2-NH2-CMC/MOF5 and γ-Fe2O3@SiO2-NH2-CMC/IRMOF3 magnetic metal–organic framework (MOF) nanoparticles which possess both magnetic characteristics and fluorescent properties. Here, [Zn4O(bdc)3] (MOF-5, bdc=1,4-benzenedicarboxylate) is a kind of shell. IRMOF3, a known MOF with a cubic topology prepared from Zn(NO3)2⋅4H2O and 2-amino-1,4-benzene dicarboxylic acid, is another kind of shell which is attractive due to its highly porous, crystalline structure and the presence of non-coordinating amino groups on the benzenedicarboxylate (bdc) linker, which are amenable to post-synthetic modification. γ-Fe2O3@SiO2-NH2-CMC magnetic nanoparticles (MNPs) could be prepared by covalent modification of sodium carboxymethyl cellulose (CMC). The structure of γ-Fe2O3 nanoparticles could be determined by X-ray powder diffraction (XRD). X-ray photoelectron spectroscopy (XPS) spectra could be used for the characterisation of γ-Fe2O3@SiO2-NH2, γ-Fe2O3@SiO2-NH2-CMC, γ-Fe2O3@SiO2-NH2-CMC/MOF5, and γ-Fe2O3@SiO2-NH2-CMC/IRMOF3 nanoparticles. Magnetic solid-phase extraction (MSPE) of enrofloxacin (Enr) experiments exhibited that, for γ-Fe2O3@SiO2-NH2-CMC/IRMOF3, the best effects of adsorption could be obtained at pH 4 and 6, while elution conditions of 0.1mol L−1 NaOH and 1% sodium dodecyl sulfate could achieve the best elution effect. The addition of Tb3+ ions could sensitise the fluorescence of Enr. At the same time, via the addition of Tb3+ ions, coordination could occur between nanoparticles and Tb3+ ions, which could be verified by XPS.

Sixty Kunming mice were randomly assigned into three groups. Mice in a control group were fed a basal diet, while mice in AFB1 group and AFB1-Se group were fed the basal diet supplemented with 250 μg/kg AFB1 or the basal diet supplemented with 250 μg/kg AFB1 and 0.2 mg/kg selenium as selenium-enriched yeast, respectively. On day 30 of the experiment, growth performance, glutathione peroxidase (GSH-Px) activities, total antioxidant capacity (T-AOC) levels, and malondialdehyde (MDA) contents in liver, interleukin-2 (IL-2), and interferon-γ (IFN-γ) contents in serum, and cytochrome P3a11 (Cyp3a11), IL-2, IFN-γ, and GSH-Px1 mRNA levels in liver were determined. The results showed that final weights, weight gains, T-AOC levels, GSH-Px1, and IFN-γ mRNA levels in AFB1-Se group and control group were higher or significantly higher than those in AFB1 group (P 0.05 or P 0.01), respectively. Body length gains in AFB1 group were lower than those in the control group (P 0.05), while there was no significant difference between the AFB1-Se and control groups (P 0.05). IL-2 contents and liver IL-2 mRNA levels in AFB1-Se group were significantly higher than those in the AFB1 group and control group (P 0.01), and IL-2 contents in the control group were also significantly higher than those in the AFB1 group (P 0.01). IFN-γ contents in AFB1-Se group and AFB1 group were significantly higher than those in control group (P 0.01), while IFN-γ contents in AFB1-Se group were significantly lower than those in AFB1 group (P 0.01). Cyp3a11 mRNA levels in AFB1-Se group and AFB1 group were significantly higher than those in the control group (P 0.01). The results indicated that selenium-enriched yeast could partly reduce the toxicity induced by AFB1 in mice, including improving growth performance, antioxidation capacity, IL-2 and IFN-γ contents, and enhancing IL-2, IFN-γ, and GSH-Px1 mRNA levels.

A sensitive, selective and reproducible immunoaffinity stir bar sorptive microextraction (SBSME) coupled with liquid chromatography-fluorescence method for determination of 11 quinolones (QNs) in bovine milk was developed and validated. It is first report of a broad-specificity monoclonal antibody to QNs that has been immobilized to glass bar for preparation of a re-usable immunoaffinity stir bar. Analytes were extracted by placing stir bar in milk and shaking on a rotary shaker for 30min at 30rpm, followed by liquid chromatography and fluorescence detection. The newly developed method has limits of detection for each QN from 0.05 to 0.1ng/g with intra-day and inter-day precision ranging from 3.2 to 11.9% and from 5.2 to 12.5%, respectively. This allowed us to quantitatively analyze drugs in bovine milk with the advantage of significantly simplified sample preparation. The proposed method was successfully applied to the bovine milk samples analyses with QNs, demonstrating its rare application in animal food safety analysis.

This study aimed to develop a bovine mammary epithelial (BME) cell line model, which provides a possibility to determine functional properties of the bovine mammary gland. The primary cell culture was derived from bovine mammary gland tissues and processed enzymatically to obtain cell colonies with epithelial-like morphology. The cultures of BME cells were purified and optimally cultured at 37 °C in DMEM/F12 medium supplemented with 10% fetal bovine serum. The BME cells were identified as epithelial cell line by the evaluating the expression of keratin-18 using immunofluorescence staining. A novel gene expression system strongly enhances the expression of telomerase, has been used to immortalize BME cell line termed hTBME cell line. Interestingly, telomerase remained active even after over 60 passages of hTBME cell line, required for immortalization of BME cells. In addition, the hTBME cell line was continuously subcultured with a spontaneous epithelial-like morphology, with a great proliferation activity, and without evidence of apoptotic and necrotic effects. Further characterization showed that hTBME cell line can be continuously propagated in culture with constant chromosomal features and without tumorigenic properties. Finally, established hTBME cell line was evaluated for mammary gland specific functions. Our results demonstrated that the hTBME cell line was able to retain functional-morphological structure, and functional differentiation by expression of beta (β)-casein as in the bovine mammary gland in vivo. Taken together, our findings suggest that the established hTBME cell line can serve as a valuable tool for the study of bovine mammary gland functions.

This paper proposes a target detector based on kernel sparse and spatial constraint for hyperspectral imagery (HSI). Due to the nonlinear and structural features of HSI data, sparse representation and spatial constraint are taken into consideration. Firstly, we construct a dictionary to represent the target pixels within a small neighborhood by a linear combination of samples. Then, these targets pixels are projected into the high-dimensional feature space through kernel function and orthogonal matching pursuit (OMP) are kernelized to obtain recovered sparse coefficient vector. By comparing the residuals of background and target to determine the type of pixel, the preliminary detection result can be achieved. Lastly, a spatial over-complete basis matrix is used to revise the initial detection result. The experimental results show that the proposed detector has better detection performance than several typical detectors.

One-pot solvothermal treatment of Co(NO3)2·6H2O, H2L (5-(3-methyl-5-(pyridin-4-yl)-4H-1,2,4-triazol-4-yl) isophthalic acid), and 4,4′-bipyridine (4,4′-bipy) in H2O/DMF (V/V = 1 : 1) yielded a cobalt-organic chain, [Co(L)(O)(H2O)2]n·1.25nH2O (1). Compound 1 as raw materials was calcined to obtain Co3O4, which could be confirmed by PXRD and SEM. Via the modification, Co3O4@SiO2-NH2 and Co3O4@SiO2-NH2-FA samples could be obtained. Compared to Co3O4@SiO2-NH2, Co3O4@SiO2-NH2-FA seems to have better peroxidase-mimetic properties. UV–vis results showed that optimal conditions of peroxidase-mimetic experiments were at 50°C in sodium acetate-acetic acid buffer (pH 3.6, 0.2 M), when the concentration of tetramethylbenzidine (TMB) was 0.2 mM. A concentration-dependent manner was shown between the concentration of glucose and absorbance in the measurement experiments for glucose.

High resolution satellite images play an important role in target detection application presently. This article focuses on the ship target detection from the high resolution panchromatic images. Taking advantage of geographic information such as the coastline vector data provided by NOAA Medium Resolution Coastline program, the land region is masked which is a main noise source in ship detection process. After that, the algorithm tries to deal with the cloud noise which appears frequently in the ocean satellite images, which is another reason for false alarm. Based on the analysis of cloud noise's feature in frequency domain, we introduce a windowed noise filter to get rid of the cloud noise. With the help of morphological processing algorithms adapted to target detection, we are able to acquire ship targets in fine shapes. In addition, we display the extracted information such as length and width of ship targets in a user-friendly way i.e. a KML file interpreted by Google Earth.

Magnetite (Fe3O4) is a ferromagnetic iron oxide of both Fe(II) and Fe(III), prepared by FeCl2 and FeCl3. XRD was used for the confirmation of Fe3O4. Via the modification of Tetraethyl orthosilicate (TEOS), (3-Aminopropyl)trimethoxysilane (APTMS), and Alginate (AA), Fe3O4@SiO2, Fe3O4@SiO2-NH2, and Fe3O4@SiO2-NH2-AA nanoparticles could be obtained, and IR and SEM were used for the characterizations. Alkaloid adsorption experiments exhibited that, as for Palmatine and Berberine, the most adsorption could be obtained at pH 8 when the adsorption time was 6 min. The adsorption percentage of Palmatine was 22.2%, and the adsorption percentage of Berberine was 23.6% at pH 8. Considering the effect of adsorption time on liquid phase system, the adsorption conditions of 8 min has been chosen when pH 7 was used. The adsorption percentage of Palmatine was 8.67%, and the adsorption percentage of Berberine was 7.25%. Considering the above conditions, pH 8 and the adsorption time of 8min could be chosen for further uses.