In situ preparation of multilayer coated capillary column with HKUST-1 for separation of neutral small organic molecules by open tubular capillary electrochromatography.

The popularity of novel nanoparticles coated capillary column has aroused widespread attention of researchers. Metal organic frameworks (MOFs) with special structure and chemical properties have received great interest in separation sciences. This work presents the investigation of HKUST-1 (Hong Kong University of Science and Technology-1, called Cu3(BTC)2 or MOF-199) nanoparticles as a new type of coating material for capillary electrochromatography. For the first time, three layers coating (3-LC), five layers coating (5-LC), ten layers coating (10-LC), fifteen layers coating (15-LC), twenty layers coating(20-LC) and twenty-five layers coating (25-LC) capillary columns coated with HKUST-1 nanoparticles were synthesized by covalent bond with in situ, layer-by-layer self-assembly approach. The results of scanning electron microscopy (SEM), X-ray diffraction (XRD) and plasma atomic emission spectrometry (ICP-AES) indicated that HKUST-1 was successfully grafted on the inner wall of the capillary. The separating performances of 3-LC, 5-LC, 10-LC, 15-LC, 20-LC and 25-LC open tubular (OT) capillary columns were studied with some neutral small organic molecules. The results indicated that the neutral small organic molecules were separated successfully with 10-LC, 15-LC and 20-LC OT capillary columns because of the size selectivity of lattice aperture and hydrophobicity of organic ligands. In addition, 10-LC and 15-LC OT capillary columns showed better performance for the separation of certain phenolic compounds. Furthermore, 10-LC, 15-LC and 20-LC OT capillary columns exhibited good intra-day repeatability with the relative standard deviations (RSDs; %) of migration time and peak areas lying in the range of 0.3-1.2% and 0.5-4.2%, respectively. For inter-day reproducibility, the RSDs of the three OT capillary columns were found to be lying in the range of 0.3-5.5% and 0.3-4.5% for migration time and peak area, respectively. The RSDs of retention times for column-to-column for three batches of 10-LC, 15-LC and 20-LC OT capillary columns were in the range from 2.3% to 7.2%. Moreover, the fabricated 10-LC, 15-LC and 20-LC OT capillary columns exhibited good repeatability and stability for separation, which could be used successively for more than 120 runs with no observable changes on the separation efficiency.

Combined Effects of Elevated pCO2 and Warming Facilitate Cyanophage Infections.

Elevated pCO2 and warming are generally expected to influence cyanobacterial growth, and may promote the formation of blooms. Yet, both climate change factors may also influence cyanobacterial mortality by favoring pathogens, such as viruses, which will depend on the ability of the host to adapt. To test this hypothesis, we grew Plectonema boryanum IU597 under two temperature (25 and 29°C) and two pCO2 (400 and 800 µatm) conditions for 1 year, after which all treatments were re-exposed to control conditions for a period of 3 weeks. At several time points during the 1 year period, and upon re-exposure, we measured various infection characteristics of it associated cyanophage PP, including the burst size, latent period, lytic cycle and the efficiency of plaquing (EOP). As expected, elevated pCO2 promoted growth of P. boryanum equally over the 1 year period, but warming did not. Burst size increased in the warm treatment, but decreased in both the elevated pCO2 and combined treatment. The latent period and lytic cycle both became shorter in the elevated pCO2 and higher temperature treatment, and were further reduced by the combined effect of both factors. Efficiency of plaquing (EOP) decreased in the elevated pCO2 treatment, increased in the warm treatment, and increased even stronger in the combined treatment. These findings indicate that elevated pCO2 enhanced the effect of warming, thereby further promoting the virus infection rate. The re-exposure experiments demonstrate adaptation of the host leading to higher biomass build-up with elevated pCO2 over the experimental period, and lower performance upon re-exposure to control conditions. Similarly, virus burst size and EOP increased when given warm adapted host, but were lower as compared to the control when the host was re-exposed to control conditions. Our results demonstrate that adaptation but particularly physiological acclimation to climate change conditions favored viral infections, while limited host plasticity and slow adaptation after re-exposure to control conditions impeded host biomass build-up and viral infections.

[Discrimination of Plum Browning with Near Infrared Spectroscopy].

Flesh browning mostly happens in plum fruit during the post-harvest storage period, which is an important factor affecting the storage quality of plum fruits. Traditional methods used to discriminate plum browning involve the destruction of the intact fruit, which are highly subjective and error-prone. Therefore, the near-infrared (NIR) spectroscopy technique was applied to achieve rapid and non-destructive identification of plum browning and non-browning in this paper. The near infrared diffuse reflectance spectroscopy of 124 plum samples were collected in the band number of 4 000~12 500 cm-1. These samples were classified into two groups, browning (n=70) and non-browning (n=54). In order to find a new way to effectively discriminate plum fruits with flesh browning, three qualitative identification methods: the qualitative test, Mahalanobis distances discriminate analysis (DA) and Back Propagation-artificial neural networks (BP-ANN) were used to compare their capacity of recognizing browning plums and non-browning oneswhile the last two approaches were based on the principal component analysis (PCA) method. These results showed that DA and BP-ANN could be used to conctruct effective classification models for identifying plum browning, and the first ten principal components extracted from original spectra were applied as input variables to build DA and BP-ANN models. The optimal method was obtained with BP-ANN, which gained an accuracy of 100% for calibration set and 97.56% for prediction set, and the identification accuracy rate reached 100% and 98.57% for non-browning samples and browning ones, respectively. It could be concluded that NIR spectroscopy technique combined with chemometrics methods has great potential to recognize plums of browning and non-browning rapidly, non-destructively and effectively.

[Discrimination of donkey meat by NIR and chemometrics].

Donkey meat samples (n = 167) from different parts of donkey body (neck, costalia, rump, and tendon), beef (n = 47), pork (n = 51) and mutton (n = 32) samples were used to establish near-infrared reflectance spectroscopy (NIR) classification models in the spectra range of 4,000~12,500 cm(-1). The accuracies of classification models constructed by Mahalanobis distances analysis, soft independent modeling of class analogy (SIMCA) and least squares-support vector machine (LS-SVM), respectively combined with pretreatment of Savitzky-Golay smooth (5, 15 and 25 points) and derivative (first and second), multiplicative scatter correction and standard normal variate, were compared. The optimal models for intact samples were obtained by Mahalanobis distances analysis with the first 11 principal components (PCs) from original spectra as inputs and by LS-SVM with the first 6 PCs as inputs, and correctly classified 100% of calibration set and 98. 96% of prediction set. For minced samples of 7 mm diameter the optimal result was attained by LS-SVM with the first 5 PCs from original spectra as inputs, which gained an accuracy of 100% for calibration and 97.53% for prediction. For minced diameter of 5 mm SIMCA model with the first 8 PCs from original spectra as inputs correctly classified 100% of calibration and prediction. And for minced diameter of 3 mm Mahalanobis distances analysis and SIMCA models both achieved 100% accuracy for calibration and prediction respectively with the first 7 and 9 PCs from original spectra as inputs. And in these models, donkey meat samples were all correctly classified with 100% either in calibration or prediction. The results show that it is feasible that NIR with chemometrics methods is used to discriminate donkey meat from the else meat.

Peripheral B-cell activation and exhaustion markers in patients with ankylosing spondylitis.

AIMS: Ankylosing spondylitis (AS) is an autoimmune disease and is associated with abnormal B cell function. However, the roles of different B cell subsets are less clear. This study aimed to examine the frequency of different subsets of B cells in AS patients following standard therapies. MAIN METHODS: Eighteen newly diagnosed AS patients and 10 healthy controls (HC) were recruited in this study. The expression of CD27, CD38, CD86, CD95 and IgD on CD19(+) B cells was examined by flow cytometry. The disease activity was scored according to the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). Serum levels of C-reactive protein (CRP), rheumatoid factor (RF), IgG, IgA and IgM, and the erythrocyte sedimentation rate (ESR) were measured. KEY FINDINGS: The frequency of CD27(+) B cells was decreased in AS patients compared with HC (p=0.018), while CD86(+) and CD27(-)CD95(+) B cell subsets increased in AS patients (p<0.001). Meanwhile, the frequencies of CD38(+) and CD95(+) B cell positively correlated with BASDAI (r=0.6505, p=0.0035; r=0.6854, p=0.0017, respectively), while CD38(-)CD86(+) B cell negatively correlated with BASDAI (r=-0.7329, p<0.001). We also found that CD27(-) and CD95(+) B cell negatively correlated with RF levels (r=-0.5141, p=0.0290; r=-0.4944, p=0.0370, respectively), while CD27(+) B cell positively correlated with IgG levels (p=0.0148, r=0.5640). Moreover, CD86(+) and CD27(-)CD95(+) B cell subsets increased following treatment with Meloxicam and Etanercept for one month (p<0.001; p<0.001). SIGNIFICANCE: These findings suggest that CD27(-)CD95(+)CD19(+) and CD86(+)CD19(+) B cells may be reasonable cellular targets for the therapeutic intervention of AS.

Preparation and characterization of open-tubular capillary column modified with graphene oxide nanosheets for the separation of small organic molecules.

A novel coated capillary was prepared by immobilizing graphene oxide (GO) on the fused-silica capillary (75 µm i.d.) which was derivatized by 3-aminopropyl-trimethoxysilane (APTMS). The bare capillary, APTMS modified capillary (NH2-capillary) and GO coated capillary (GO-capillary) were characterized by streaming potentials (SPs), fluorescence microscope and scanning electron microscope (SEM). The results indicated that the capillary was successfully modified with GO sheets via covalent bonding and electrostatic effect. Compared with bare capillary, greater separation efficiency was achieved by GO-capillary column as a result of the increasing interactions between the small organic molecules and the inner wall of the GO-capillary column originated from the π-π electrostatic stacking. For three consecutive runs, the intra-day relative standard deviations (RSDs) of migration time and peak areas were 0.6-4.3% and 2.8-9.3%, respectively. The inter-day relative standard deviations of migration time and peak areas were 0.2-8.3% and 4.5-9.6%. Additionally, one GO-capillary column could be used for more than 100 runs with no observable changes on the separation efficiency.

[Nondestructive discrimination of strawberry varieties by NIR and BP-ANN].

Strawberry variety is a main factor that can influence strawberry fruit quality. The use of near-infrared reflectance spectroscopy was explored discriminate among samples of strawberry of different varieties. And the significance of difference among different varieties was analyzed by comparison of the chemical composition of the different varieties samples. The performance of models established using back propagation-artificial neural networks (BP-ANN), least squares-support vector machine and discriminant analysis were evaluated on spectra range of 4545-9090 cm(-1). The optimal model was obtained by BP-ANN with a topology of 12-18-3, which correctly classified 96.68% of calibration set and 97.14% of prediction set. And the 94.95%, 97% and 98.29% classifications were given respectively for "Tianbao" (n=99), "Fengxiang" (n=100) and "Mingxing" (n=117). One-way analysis of variance was made for comparison of the mean values for soluble solids content (SSC), titratable acid (TA), pH value and SSC-TA ratio, and the statistically significant differences were found. Principal component analysis was performed on the four chemical compositions, and obvious clustering tendencies for different varieties were found. These results showed that NIR combined with BP-ANN can discriminate strawberry of different varieties effectively, and the difference in chemical compositions of different varieties strawberry might be a chemical validation for NIR results.

Determination of soluble solid content and acidity of loquats based on FT-NIR spectroscopy.

The near infrared (NIR) spectroscopy technique has been applied in many fields because of its advantages of simple preparation, fast response, and non-destructiveness. We investigated the potential of NIR spectroscopy in diffuse reflectance mode for determining the soluble solid content (SSC) and acidity (pH) of intact loquats. Two cultivars of loquats (Dahongpao and Jiajiaozhong) harvested from two orchards (Tangxi and Chun'an, Zhejiang, China) were used for the measurement of NIR spectra between 800 and 2500 nm. A total of 400 loquats (100 samples of each cultivar from each orchard) were used in this study. Relationships between NIR spectra and SSC and acidity of loquats were evaluated using partial least square (PLS) method. Spectra preprocessing options included the first and second derivatives, multiple scatter correction (MSC), and the standard normal variate (SNV). Three separate spectral windows identified as full NIR (800approximately2500 nm), short NIR (800approximately1100 nm), and long NIR (1100approximately2500 nm) were studied in factorial combination with the preprocessing options. The models gave relatively good predictions of the SSC of loquats, with root mean square error of prediction (RMSEP) values of 1.21, 1.00, 0.965, and 1.16 degrees Brix for Tangxi-Dahongpao, Tangxi-Jiajiaozhong, Chun'an-Dahongpao, and Chun'an-Jiajiaozhong, respectively. The acidity prediction was not satisfactory, with the RMSEP of 0.382, 0.194, 0.388, and 0.361 for the above four loquats, respectively. The results indicate that NIR diffuse reflectance spectroscopy can be used to predict the SSC and acidity of loquat fruit.

[Application of Vis/NIR diffuse reflectance spectroscopy to the detection and identification of transgenic tomato leaf].

The feasibility of Vis/NIR spectroscopy technique for rapid and non-invasive detection of transgenic tomato leaves from conventional ones was investigated by means of spectral diffuse reflectance mode. A total of 68 samples (38 transgenic ones and 30 non-transgenic ones) were used for classification. The calibration and validation results were analyzed via discriminant analysis (DA) and partial least squares (PLS) discriminant method using TQ 6.2. 1 quantitative software. Models based on the different spectral pre-processing methods (multiplicative signal correction (MSC), first and second derivative) were compared. It was found that the classification accuracy using DA was higher than that using PLS and the best results were gained by using spectra after MSC with InGaAs detector and the classification accuracy was 89.7% (accuracy of 86.8% for transgenic samples and 93.3% for non-transgenic ones). The results show that Vis-NIR diffuse reflectance spectroscopy technique is a feasible and fast method for non-invasive detection of transgenic and non-transgenic tomato leaves.

[Application of infrared spectroscopy technique to discrimination of alcoholic beverages].

Infrared spectroscopy technique is a rapid for the discrimination of food samples, and is widely used to detect and discriminate various beverages. This paper presents the advantages and disadvantages of techniques that have been used to discriminate alcoholic beverages, and the discriminating procedure with infrared spectroscopy technique. Applications of infrared spectroscopy technique to wine, whiskey, Japanese sake and Chinese rice wine etc. is presented too. Finally, problems in applications are analyzed, and the application of infrared spectroscopy technique to the discrimination of our traditional alcoholic beverages is prospected.

[Application of NIR quantitative analysis to nondestructive detection of loquat soluble solid content].

The objective of the present research was to evaluate the potential of NIR diffuse reflectance spectroscopy as a way for nondestructive measurement of loquat soluble solid content of three varieties harvested from two orchards. According to the analysis, it was shown that the correlation coefficient of curves was relatively high in the two regions of 1400-1500 nm and 1900- 2000 nm. Statistical models were developed using partial least square regression (PLSR), stepwise multiple linear regression (SMLR) and principal component regression (PCR) methods in the full spectral region from 800 to 2500 nm and in the combined region of 1400-1500 nm and 1900-2000 nm. The results of PLSR model in the full spectral region were better than those of other models. The modeling results based on derivative spectra were not as good as those based on original spectra. Finally, a model was established based on the original spectra with 17 points smoothing for all the three varieties in the full spectral region by PLSR method. The correlation coefficients of calibration and validation were 0.96 and 0.95, respectively. The results indicate that it is feasible to use NIR spectroscopy technique for quantitative analysis of loquat soluble solid content.

[Effect of ginsenoside on the cellular proliferation, apoptosis and cell cycles in LC A549 and HUVEC 304 cell lines].

OBJECTIVE: To determine the effect of ginsenoside on the cellular proliferation, apoptosis and cell cycles in LC A549 and HUVEC 304 cell lines. METHODS: A549 and HUVEC 304 cell lines were cultured with different concentrations of ginsenoside. Cellular proliferation was detected with MTT, apoptosis and cell cycles were checked with Flow Cytometer, and change of microstructure was observed by transmission electron microscope. RESULTS: The apoptosis rate was 29.8% in A549 cell lines after being interfered with ginsenoside at 3 x 10(-6) mol/L, significantly higher than that in the control group ( P < 0.05). No change was observed in the cell cycles after being interfered with ginsenoside. The inhibitive rate of ginsenoside was 12.53% for HUVEC 304 cell line at 1 x 10(-4) mol/L (P < 0.05 ). The cells induced by conditioned medium could be inhibited by ginsenoside, and apoptotic body could be found in cells induced by conditioned medium at 10(-6) mol/L. CONCLUSION: The proliferation of vascular endothelial cell could be inhibited by ginsenoside, and apoptosis could also be found in both tumor cells and cells induced by conditioned medium after being interfered with ginsenoside.

[The inhibition of 20(R)-ginsenoside Rg3 on the expressions of angiogenesis factors proteins in human lung adenocarcinoma cell line A549 and HUVEC304 cell].

OBJECTIVE: To study the effect of 20( R)-ginsenoside Rg3 on the expressions of angiogenesis factors proteins (VEGF,bFGF, MMP-2) in human lung adenocarcinoma cell line A549 and HUVEC304 cell. METHOD: The cell lines of A549 and HUVEC304 were cultured with 20(R)- Rg3. The gray scale and positive rate of VEGF, bFGF, MMP-2 were detected by immunohistochemistry. The differential expressions of genes were studied by DNA microarray. RESULT: The positive rate of VEGF protein in A549 cell decreased significantly as compared with the control group ( P = 0.03). The gray scales of VEGF, Flt, KDT proteins in both A549 cell lines and HUVEC 304 cell lines decreased ( P = 0.05). Gray scale of MMP-2 also decreased in A549 cell lines. The result of differential expressions of genes of A549 cell lines showed that 14 genes were down-regulated and 10 genes were up-regulated. CONCLUSION: The Chinese materia medica of 20( R)-Rg3 can inhibit the expression of angiogenesis factors proteins via several target genes in both tumour cell and vascular endothelial cell.