Search

A novel and efficient immunoaffinity column (IAC) based on bispecific monoclonal antibody (BsMAb) recognizing aflatoxin B1 (AFB1) and ochratoxin A (OTA) was prepared and applied in simultaneous extraction of AFB1 and OTA from food samples and detection of AFB1/OTA combined with ic-ELISA (indirect competitive ELISA). Two deficient cell lines, hypoxanthine guanine phosphoribosyl-transferase (HGPRT) deficient anti-AFB1 hybridoma cell line and thymidine kinase (TK) deficient anti-OTA hybridoma cell line, were fused to generate a hybrid-hybridoma producing BsMAb against AFB1 and OTA. The subtype of the BsMAb was IgG1 via mouse antibody isotyping kit test. The purity and molecular weight of BsMAb were confirmed by SDS-PAGE method. The cross-reaction rate with AFB2 was 37%, with AFG1 15%, with AFM1 48%, with AFM2 10%, and with OTB 36%. Negligible cross-reaction was observed with other tested compounds. The affinity constant (Ka) was determined by ELISA. The Ka (AFB1) and Ka (OTA) was 2.43 × 108 L/mol and 1.57 × 108 L/mol, respectively. Then the anti-AFB1/OTA BsMAb was coupled with CNBr-Sepharose, and an AFB1/OTA IAC was prepared. The coupling time and elution conditions of IAC were optimized. The coupling time was 1 h with 90% coupling rate, the eluent was methanol–water (60:40, v:v, pH 2.3) containing 1 mol/L NaCl, and the eluent volume was 4 mL. The column capacities of AFB1 and OTA were 165.0 ng and 171.3 ng, respectively. After seven times of repeated use, the preservation rates of column capacity for AFB1 and OTA were 69.3% and 68.0%, respectively. The ic-ELISA for AFB1 and OTA were applied combined with IAC. The IC50 (50% inhibiting concentration) of AFB1 was 0.027 ng/mL, the limit of detection (LOD) was 0.004 ng/mL (0.032 µg/kg), and the linear range was 0.006 ng/mL~0.119 ng/mL. The IC50 of OTA was 0.878 ng/mL, the LOD was 0.126 ng/mL (1.008 µg/kg), and the linear range was 0.259 ng/mL~6.178 ng/mL. Under optimum conditions, corn and wheat samples were pretreated with AFB1-OTA IAC. The recovery rates of AFB1 and OTA were 95.4%~105.0% with ic-ELISA, and the correlations between the detection results and LC-MS were above 0.9. The developed IAC combined with ic-ELISA is reliable and could be applied to the detection of AFB1 and OTA in grains.

In this study, forchlorfenuron (CPPU) was coupled with succinic anhydride to yield a CPPU hapten (CPPU-COOH), and a high-affinity monoclonal antibody (mAb) that can specifically recognize CPPU was produced. Using this mAb as a recognition reagent, a sensitive indirect competitive enzyme-linked immunosorbent assay (icELISA) for CPPU was optimized, which exhibits an IC50 of 1.04 ng/mL, a limit of detection of 0.16 ng/mL, and a linear range of 0.31–3.43 ng/mL for CPPU. Cross-reactivity percentages with six analogues were all below 6%. The average recovery rates for cucumber and orange samples were from 85.23% to 119.14%. The analysis results of this icELISA showed good consistency with those from liquid chromatography mass spectrometry. These results suggest that the proposed icELISA provides a sensitive, specific, and reliable strategy for CPPU detection in food samples.

Introduction. The aim of this paper is to examine and model how marketingprofessionals seek,judge, use, and share information in the workplace. Method. The study consists of two stages: first, a questionnaire was conducted with eleven marketing professionals, and seven of them completed an intensive five-day diary study followed by semi-structured interviews at the second stage. Analysis. The open coding method was applied to the 1,198 diary entries, which encompassed 101 real work tasks demanding active information seeking, and to the interview transcripts. Results. Marketing professionals were found to spend approximately two to three hours a day seeking information. Most information was found from internal documents (47%) and external search engines and websites (21%). More attention was devoted to quality factors than to cost when they chose information sources, and reliability (20%) and accuracy (16%) were perceived important. The obtained information was used for information processing, knowledge construction, information production, and applying information. Five dimensions of information sharing occurrences were uncovered, including people, purpose, mode, content, and level of pro-activeness. Conclusions. A model of information behaviour incorporating information seeking, judgement, use and sharing was developed. [ABSTRACT FROM AUTHOR]

A recently proposed product quantization method is efficient for large scale approximate nearest neighbor search, however, its performance on unstructured vectors is limited. This paper introduces residual vector quantization based approaches that are appropriate for unstructured vectors. Database vectors are quantized by residual vector quantizer. The reproductions are represented by short codes composed of their quantization indices. Euclidean distance between query vector and database vector is approximated by asymmetric distance, i.e., the distance between the query vector and the reproduction of the database vector. An efficient exhaustive search approach is proposed by fast computing the asymmetric distance. A straight forward non-exhaustive search approach is proposed for large scale search. Our approaches are compared to two state-of-the-art methods, spectral hashing and product quantization, on both structured and unstructured datasets. Results show that our approaches obtain the best results in terms of the trade-off between search quality and memory usage. [ABSTRACT FROM AUTHOR]

In this paper, it is presented that electromyography (EMG) is a shot noise based on the generation of EMG. A novel filter is proposed by applying a neural network (NN) ensemble where the noisy input signal and the desired one are the same in a learning process. Both incremental and batch mode are applied in the learning process of NNs that is better than generalized NN filters. This NN ensemble filter not only reduces additive and multiplicative white noise inside signals, but also preserves the signals' characteristics. In clinical EEG and EMG signals processing, the filter is capable of reducing EMG in the clinical EEG, and it is proved that there is randomness in EMG. [ABSTRACT FROM AUTHOR]

Purpose To investigate the clinical application of fluorescence in situ hybridization (FISH) for assessing chromosome disorders of embryos in preimplantation diagnosis of carriers with der(15)t(Y;15)(q12;p11) translocations. Methods Multicolor FISH was performed using directly-labelled DNA probes, chromosome X with one (DXZ1, Xp11.1-q11.1), but Y with two (DYZ3, Yp11.1-q11.1 and DYZ1, Yq12). Normal embryos were transferred on day 6 at blastocyst stage. Results Couple A: Three of 6 biopsied embryos were normal. Two normal blastocysts were transferred, but no pregnancy was achieved. Couple B: Three of 6 biopsied embryos were normal. Two normal blastocysts were transferred. A normal male infant weighing 3,230 g was born by cesarean section on the 39th week of gestation. All of the remaining nonreplaced embryos showed mosaic or der(15). Conclusion Embryos from carries of der(15)t(Y;15)(q12; p11) translocation showed a high frequency of chromosome abnormalities. PGD is a valuable screen tool for those couples to treat their infertility and break the transmission of der(15) chromosome for their offspring. [ABSTRACT FROM AUTHOR]

Purpose To provide more genetic information about meiotic segregation behavior and the possibility of interchromosomal effects (ICE) in spermatozoa from carriers of Robertsonian (Rob) translocations. Materials and methods Meiotic segregation behavior in spermatozoa from six carriers of Rob translocations, four t(13;14), one t(14;22) and one t(13;21), was investigated by dual fluorescence in-situ hybridization (FISH). Aneuploidy for chromosomes 18, X and Y was studied by triple FISH. Results The rate of normal/balanced spermatozoa resulting from alternate segregation ranged from 78.14 to 86.88%. The frequency of unbalanced spermatozoa resulting from adjacent segregation varied between 11.70 and 19.53%. The higher frequencies of aneuploidy for sex chromosome were observed in three Rob translocation carriers. In addition, the increased rates of diploid were found in two t(13;14) carriers. Conclusions Alternate segregation is dominant in the different types of Rob translocations. Some carriers may be at an increased risk for ICE. [ABSTRACT FROM AUTHOR]

Magnesium-based bulk metallic glass matrix composites (BMGMCs) have better plasticity than the corresponding bulk metallic glasses (BMGs); however, their strength and density are often compromised due to the fact that the effective reinforcement phase is mostly plastic heavy metal. For lightweight SiC-particle reinforced BMGMCs, interface wettability and the sharpness of the particles often reduce the strengthening effect. In this work, SiC particles were coated with a thin Cu coating by electroless plating, and added to Mg54Cu26.5Ag8.5Gd11 melt in an amount of 5 wt % to prepare a BMGMC. The microstructure of the interface, mechanical behavior and fracture morphology of the BMGMC were studied by scanning electron microscopy and quasi-static compression testing. The results showed that the Cu coating improved the wettability between SiC and the matrix alloy without obvious interfacial reactions, leading to the dispersion of SiC particles in the matrix. The addition of Cu-coated SiC particles improved the plastic deformation ability of Mg54Cu26.5Ag8.5Gd11 BMG, proving that electroless plating was an effective method for controlling the interface microstructure and mechanical behavior of BMGMCs.

Achieving accurate registration between real and synthetic worlds is one of the most difficult problems in augmented reality (AR) systems. A proposed real-time camera-pose estimation method solves the registration problem for wide-area AR applications through two unique features. First, this method employs multiple maps and local bundle adjustment, which solve problems associated with online scene reconstruction. This enables the registration to work without prior knowledge of natural scenes, thus greatly enhancing AR systems' usability. Second, this method redefines the class of traditional ferns and proposes a recognition technique for online learning and recognition of keyframes. (A fern is a nonhierarchical structure consisting of a small set of binary tests; it returns the probability that an image patch belongs to any one of the learned classes.) The result is a system that can learn keyframes dynamically and switch between different scenes automatically, even in large-scale workspaces. [ABSTRACT FROM PUBLISHER]

Although sperm dysfunction is the single most common cause of infertility, we have poor methods of diagnosis and surprisingly no effective treatment (excluding assisted reproductive technology). In this review, we challenge the usefulness of a basic semen analysis and argue that a new paradigm is required immediately. We discuss the use of at-home screening to potentially improve the diagnosis of the male and to streamline the management of the sub-fertile couple. Additionally, we outline the recent progress in the field, for example, in proteomics, which will allow the development of new biomarkers of sperm function. This new knowledge will transform our understanding of the spermatozoon as a machine and is likely to lead to non-ART treatments for men with sperm dysfunction. [ABSTRACT FROM AUTHOR]

Increasing temperatures and drought in desert ecosystems are predicted to cause decreased vegetation density combined with barren ground expansion. It remains unclear how nutrient availability, microbial diversity, and the associated functional capacity vary between the vegetated canopy and gap soils. The specific aim of this study was to characterize canopy versus gap microsite effect on soil microbial diversity, the capacity of gap soils to serve as a canopy soil microbial reservoir, nitrogen (N)-mineralization genetic potential (ureC gene abundance) and urease enzyme activity, and microbial-nutrient pool associations in four arid-hyperarid geolocations of the western Sonoran Desert, Arizona, United States. Microsite combined with geolocation explained 57% and 45.8% of the observed variation in bacterial/archaeal and fungal community composition, respectively. A core microbiome of amplicon sequence variants was shared between the canopy and gap soil communities; however, canopy soils included abundant taxa that were not present in associated gap communities, thereby suggesting that these taxa cannot be sourced from the associated gap soils. Linear mixed-effects models showed that canopy soils have significantly higher microbial richness, nutrient content, and organic N-mineralization genetic and functional capacity. Furthermore, ureC gene abundance was detected in all samples, suggesting that ureC is a relevant indicator of N mineralization in deserts. Additionally, novel phylogenetic associations were observed for ureC, with the majority belonging to Actinobacteria and uncharacterized bacteria. Thus, key N-mineralization functional capacity is associated with a dominant desert phylum. Overall, these results suggest that lower microbial diversity and functional capacity in gap soils may impact ecosystem sustainability as aridity drives open-space expansion in deserts. [ABSTRACT FROM AUTHOR]

Dendritic cells (DCs) play important roles in the initiation of immune response and also in the maintenance of immune tolerance. Now, many kinds of regulatory DCs with different phenotypes have been identified to suppress immune response and contribute to the control of autoimmune diseases. However, the mechanisms by which regulatory DCs can be regulated to exert the immunosuppressive function in the immune microenvironment remain to be fully investigated. In addition, how T cells, once activated, can feedback affect the function of regulatory DCs during immune response needs to be further identified. We previously identified a unique subset of CD11bhiIalow regulatory DCs, differentiated from mature DCs or hematopoietic stem cells under a stromal microenvironment in spleen and liver, which can negatively regulate immune response in a feedback way. Here, we show that CD11bhiIalow regulatory DCs expressed high level of Fas, and endothelial stromal cell-derived TGF-β could induce high expression of Fas on regulatory DCs via ERK activation. Fas ligation could promote regulatory DCs to inhibit CD4+ T cell proliferation more significantly. Furthermore, Fas ligation preferentially induced regulatory DCs to produce IL-10 and IP-10 via ERK-mediated inactivation of GSK-3 and subsequent up-regulation of β-catenin. Interestingly, activated T cells could promote regulatory DCs to secrete more IL-10 and IP-10 partially through FasL. Therefore, our results demonstrate that Fas signal, at least from the activated T cells, can promote the immunosuppressive function of Fas-expressing regulatory DCs, providing a new manner for the regulatory DCs to regulate adaptive immunity. [ABSTRACT FROM AUTHOR]

Dendritic cells (DCs) play critical roles in cross-priming to induce the CTL response against infection; however, the molecular mechanisms for the regulation of DC cross-priming need to be investigated further, which may help to improve the potency of DC vaccines through engineering modifications. Our previous studies showed that ß2 integrin CDllb could control TLR-triggered NK cell cytotoxicity and macrophage inflammatory responses. CDllb is also abundantly expressed in DCs, but it is unknown whether CDllb participates in the regulation of DC cross-priming for the CTL response. Also, because microRNAs (miRNAs) are important regulators of the immune response, it remains unclear whether miRNAs are regulated by CDllb in DCs. In this study, we showed that CDllb deficiency upregulated TLR9-triggered, but not TLR4-triggered, IL-12p70 production in DCs, subsequently promoting DC cross-priming of the CTL response. Further experiments showed that CDllb selectively promoted TLR9- triggered miR-146a upregulation in DCs by sustaining late-phase NF-KB activation. Additionally, Notchl, a known positive regulator of IL-12p70 production in DCs, was confirmed to be directly targeted by miR-146a. miR-146a upregulation and Notchl repression were determined to be responsible for the reduced IL-12p70 production in TLR9-triggered wild-type DCs compared with that in CD lib-deficient DCs. Therefore, CDllb and downstream miR-146a may be new negative regulators for DC crosspriming by suppressing Notchl expression and IL-12p70 production. Our data indicate a new mechanism for the regulation of DC cross-priming through integrins and miRNAs. [ABSTRACT FROM AUTHOR]