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1.
Sci Data ; 11(1): 463, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38714688

ABSTRACT

Adverse perinatal factors can interfere with the normal development of the brain, potentially resulting in long-term effects on the comprehensive development of children. Presently, the understanding of cognitive and neurodevelopmental processes under conditions of adverse perinatal factors is substantially limited. There is a critical need for an open resource that integrates various perinatal factors with the development of the brain and mental health to facilitate a deeper understanding of these developmental trajectories. In this Data Descriptor, we introduce a multicenter database containing information on perinatal factors that can potentially influence children's brain-mind development, namely, periCBD, that combines neuroimaging and behavioural phenotypes with perinatal factors at county/region/central district hospitals. PeriCBD was designed to establish a platform for the investigation of individual differences in brain-mind development associated with perinatal factors among children aged 3-10 years. Ultimately, our goal is to help understand how different adverse perinatal factors specifically impact cognitive development and neurodevelopment. Herein, we provide a systematic overview of the data acquisition/cleaning/quality control/sharing, processes of periCBD.


Subject(s)
Brain , Child Development , Child , Child, Preschool , Humans , Brain/growth & development , Brain/diagnostic imaging , China , Cognition , Databases, Factual , Neuroimaging
2.
Foods ; 11(8)2022 Apr 15.
Article in English | MEDLINE | ID: mdl-35454740

ABSTRACT

An immuno-separated assay for ochratoxin A detection coupled with a nano-affinity cleaning up for LC-confirmation was developed. Firstly, ochratoxin A was modified to quantum dot beads for immuno-fluorescent reporters. Secondly, Fe3O4 magnetic nanoparticles were conjugated with protein G for immuno-magnetic adsorbents. The immuno-separation of fluorescent reporters by magnetic adsorbents could be completed by ochratoxin A, so the fluorescent reporters released from the immune complex indicate a linear correlation with the concentration of ochratoxin A. Furthermore, the immuno-separated ochratoxin A can be eluted from magnetic adsorbent for LC-conformation. The optimized assay showed results as follows: the quantitative range of the immuno-separated assay was 0.03-100 ng mL-1 of ochratoxin A. The recoveries for spiked samples ranged from 78.2% to 91.4%, with the relative standard deviation (RSD) being 11.9%~15.3%. Statistical analysis indicated no significant difference between the HPLC-FLD results based on commercial affinity column and by nano-affinity cleaning up.

3.
J Cardiovasc Nurs ; 37(4): 350-358, 2022.
Article in English | MEDLINE | ID: mdl-37707968

ABSTRACT

BACKGROUND: The theory of planned behavior (TPB), combined with social support, forms the extended TPB, which has shown to predict adherence to health-related behavior effectively, but few studies have applied it to explain medication adherence in patients with coronary heart disease (CHD) after percutaneous coronary intervention (PCI). OBJECTIVES: The aim of this study was to explore the factors associated with medication adherence and the underlying mechanisms based on the extended TPB among patients with CHD after PCI. METHODS: A cross-sectional descriptive study was conducted among patients with CHD after PCI in 2 major hospitals in Guangzhou, China. Medication adherence was measured with the Medication Adherence Report Scale. Constructs of the TPB contributing to medication adherence were assessed by the Theory of Planned Behavior Questionnaire for Medication Adherence. Social support was measured by the Multidimensional Scale of Perceived Social Support. Structural equation modeling was used to examine the hypotheses based on the extended TPB. RESULTS: A total of 300 patients were surveyed and 26.0% of them were nonadherent. The structural equation modeling had good fit indices and estimated 62.6% of the variance in medication adherence. Regarding the relationships between the extended TPB constructs and medication adherence, "intention" was directly associated with medication adherence, and "perceived behavioral control" positively predicted medication adherence directly and indirectly. "Affective attitude" and "subjective norm" were indirectly associated with medication adherence through "intention." Social support exerted an indirect effect on medication adherence through "subjective norm." CONCLUSIONS: The extended TPB is an appropriate model to predict medication adherence and provides an effective framework for adherence-enhancing interventions.


Subject(s)
Coronary Disease , Percutaneous Coronary Intervention , Humans , Theory of Planned Behavior , Latent Class Analysis , Cross-Sectional Studies , Intention , Medication Adherence , Surveys and Questionnaires , Coronary Disease/drug therapy , Coronary Disease/surgery
4.
J Agric Food Chem ; 68(7): 2193-2200, 2020 Feb 19.
Article in English | MEDLINE | ID: mdl-31976658

ABSTRACT

Various mycotoxins widely co-exist in agro-products, and their combined effects cause toxicity and potential carcinogenicity to humans and animals. In this work, we developed an economical and sensitive quantum dots (QDs)/QD microbead (QDs/QB)-based multiplex immunochromatographic assay (mICA) for the rapid detection of fumonisin B1 (FB1), zearalenone (ZEN), and ochratoxin A (OTA) without the building-up process of mycotoxin conjugates. QDs and QBs were selected as fluorescent reporters and conjugated with antimycotoxin monoclonal antibodies for improving sensitivity. Furthermore, phage-displayed FB1, ZEN, and OTA mimotope peptide-based soluble and monovalent fusions to maltose-binding protein (MBP) were applied onto the test line of the mICA as the mimetic coating antigen. Under the optimized conditions, the visual detection limits (vLODs) of peptide-MBP-based mICA could be obtained as 0.25 ng/mL for FB1, 3.0 ng/mL for ZEN, and 0.5 ng/mL for OTA within 10 min. The results for spiked real sample detection indicate good accuracy, reproducibility, and practicability. In addition, the proposed mICA was comparable with ultraperformance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) in terms of reliability in detecting FB1, ZEN, and OTA using natural samples. From the point of promoting commercial production, these time-saving and low-cost peptide-MBP antigens applied in ICA might provide promising potential for promoting productivity and decreasing the cost of production.


Subject(s)
Fumonisins/analysis , Immunoassay/methods , Ochratoxins/analysis , Zearalenone/analysis , Food Contamination/analysis , Immunoassay/economics , Immunoassay/instrumentation , Limit of Detection , Maltose-Binding Proteins/chemistry , Quantum Dots/chemistry
5.
Int J Ophthalmol ; 12(7): 1116-1121, 2019.
Article in English | MEDLINE | ID: mdl-31341801

ABSTRACT

AIM: To study the effect of an innovative micro-dissection procedure by radiofrequency ablation (MRA) in removing eyelid nevus. METHODS: Fifty-six consecutive outpatients with eyelid nevus were treated with MRA using a monopolar device. The effect of MRA was determined after following-up for 6mo to 5y. RESULTS: Fifty-two cases (52 eyes, 92.9%) were cured once, and 4 cases (4 eyes, 7.1%) received second treatment for small residual. All cases healed well after surgery, with no pigmentation, no scars, no loss of eyelashes, no deformation of eyelid margin. There was no visual impairment after healing. CONCLUSION: MRA of eyelid nevus using the XL-RFA device is highly efficient without significant complications.

6.
Talanta ; 194: 919-924, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30609625

ABSTRACT

Here, we demonstrated a new approach for development of an ultrasensitive and green electrochemical immunosensor for Ochratoxin A (OTA). Phage displayed mimotope peptide of OTA was used as mimics of conventional competing antigen, which is chemical synthesized with toxic mycotoxins OTA as raw material, in a competitive sensing platform. The working electrode was modified by polyethylene glycol (PEG) for the purpose of immobilizing antibody effectively. Under the optimized test condition, the limit of detection (LOD) of the established immunosensor was 2.04 fg/mL, and the linear range was 7.17-548.76 fg/mL. Specific measurement of this established method was conducted by testing cross-reactivity of other common mycotoxins, the result showed that mimotope peptide-based immunosensor has negligible cross-reactivity with other mycotoxins. Furthermore, the novel concept of phage displayed mimotope peptide-based immunosensor may provide a potential application in general method for the ultrasensitive detection of various toxic small molecules in food.


Subject(s)
Biosensing Techniques/methods , Epitopes/chemistry , Immunoassay/methods , Limit of Detection , Ochratoxins/analysis , Peptide Library , Peptides/chemistry , Antibodies, Immobilized/chemistry , Antibodies, Immobilized/immunology , Electrochemistry , Electrodes , Epitopes/immunology , Green Chemistry Technology , Linear Models , Peptides/immunology , Polyethylene Glycols/chemistry
7.
Huan Jing Ke Xue ; 39(1): 300-309, 2018 Jan 08.
Article in Chinese | MEDLINE | ID: mdl-29965696

ABSTRACT

Annual drainage is a typical management activity practiced by operators as a way to export aquaculture effluent, accelerate aerobic decomposition of bottom soils, and avoid eutrophication during the non-culture period after harvest. Drainage activities can cause large changes in hydrology, nutrient cycling, sediment physicochemical properties, and even broad ecosystem functions. In order to understand the effects of drainage on the diurnal variation characteristics and magnitude of greenhouse gas (CH4 and N2O) fluxes from the aquaculture ponds of the estuaries, a 24-hour continuous monitoring was conducted from one undrained pond (UDP) and one drained pond (DP) during early winter in the Minjiang River estuary on the southeast coast of China. Over the entire study period, the fluxes of CH4 from the UDP and DP ranged from 0.04 to 0.10 mg·(m2·h)-1 and 14.04 to 33.72 mg·(m2·h)-1, respectively, with means of (0.07±0.01) mg·(m2·h)-1 and (24.74±2.33) mg·(m2·h)-1. The CH4 flux was lower during the day and higher at night with a net flux as the sources of the CH4. The fluxes of N2O from the UDP ranged from -0.027 to 0.011 mg·(m2·h)-1, and the average fluxes of (0.002±0.004) mg·(m2·h)-1 showed "weak absorption by day and emission at night." The N2O fluxes from the DP were emitted all day (ranging from 0.59 to 1.76 mg·(m2·h)-1) with the average fluxes of N2O (1.07±0.15) mg·(m2·h)-1 indicating higher fluxes at night and lower fluxes during the day. Our research demonstrated that drainage would significantly enhance CH4 and N2O release from the aquaculture ponds. The study also preliminarily confirms that the undrained pond converted to a drained pond considerably alter the diurnal variation characteristics of the CH4 and N2O emissions during early winter. Clearly, future measurements in situ at high frequency over a long time and at different spatial scales would be worth researching from drained aquaculture ponds.

8.
Talanta ; 179: 646-651, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-29310289

ABSTRACT

The rapid and widespread adoption of Bacillus thuringiensis (Bt) proteins in genetically modified (GM) crops has raised concerns about the impact of GM crops on environment and food safety. A sensitive and specific method for detecting Bt proteins in GM crops is of great significance for environment and food risk assessment. In this study, using Cry1Ab as a model Bt protein, an ultrasensitive electrochemical immunosensor for Cry1Ab protein has been developed based on phage displayed peptide. Phage displayed peptides against Cry1Ab protein were obtained from a phage displayed peptide library without animal immunization process through biopanning-elution strategy. After modification of electrode with gold nanoparticles, selected phage displayed peptide was applied to electrochemical immunosensor for Cry1Ab. Under the optimized conditions, the peptide-based immunosensor showed a dynamic range of 0.01-100ng/mL and a limit detection of 7pg/mL. Specific measurement of this established method was conducted by testing cross-reactivity of Cry1Ac (88% amino acid sequence homology to Cry1Ab protein), and the result showed that peptide-based immunosensor has negligible cross-reactivity with analogue. In addition, the accuracy and reproducibility of this established immunosensor was evaluated by testing the recovery of spiked samples and assay coefficients of variation, respectively. The results showed that the average recovery of corn and wheat sample was 90-120% and 86.7-120%, respectively; the intra-assay coefficient of variation was 7.4% (n = 6), and the inter-assay coefficient of variation was 6.9% (n = 6) at 1ng/mL Cry1Ab solution. Furthermore, the novel concept of peptide-based immunosensor may provide a potential application in general method for the ultrasensitive detection of various Bt proteins.


Subject(s)
Bacterial Proteins/analysis , Biosensing Techniques , Crops, Agricultural/chemistry , Endotoxins/analysis , Hemolysin Proteins/analysis , Immunoassay , Insecticides/analysis , Zea mays/chemistry , Antibodies, Monoclonal/chemistry , Bacillus thuringiensis/chemistry , Bacillus thuringiensis/genetics , Bacillus thuringiensis/metabolism , Bacillus thuringiensis Toxins , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Biological Variation, Individual , Crops, Agricultural/genetics , Crops, Agricultural/metabolism , Electrochemical Techniques , Electrodes , Endotoxins/genetics , Endotoxins/metabolism , Gene Expression , Gold/chemistry , Hemolysin Proteins/genetics , Hemolysin Proteins/metabolism , Insecticides/chemistry , Insecticides/metabolism , Limit of Detection , Metal Nanoparticles/chemistry , Peptide Library , Plants, Genetically Modified , Protein Isoforms/analysis , Protein Isoforms/genetics , Protein Isoforms/metabolism , Transgenes , Zea mays/genetics , Zea mays/metabolism
9.
Talanta ; 147: 523-30, 2016 Jan 15.
Article in English | MEDLINE | ID: mdl-26592642

ABSTRACT

Immunoassay for cancer biomarkers plays an important role in cancer prevention and early diagnosis. To the development of immunoassay, the quality and stability of applied antibody is one of the key points to obtain reliability and high sensitivity for immunoassay. The main purpose of this study was to develop a novel immunoassay for ultrasensitive detection of cancer biomarker alpha-fetoprotein (AFP) based on nanobody against AFP. Two nanobodies which bind to AFP were selected from a phage display nanobody library by biopanning strategy. The prepared nanobodies are clonable, thermally stable and applied in both sandwich enzyme linked immunoassay (ELISA) and immuno-PCR assay for ultrasensitive detection of AFP. The limit detection of sandwich ELISA setup with optimized nanobodies was 0.48ng mL(-1), and the half of saturation concentration (SC50) value was 6.68±0.56ng mL(-1). These nanobodies were also used to develop an immuno-PCR assay for ultrasensitive detection of AFP, its limit detection values was 0.005ng mL(-1), and the linear range was 0.01-10,000ng mL(-1). These established immunoassays based on nanobodies were highly specific to AFP and with negligible cross reactivity with other tested caner biomarkers. Furthermore, this novel concept of nanobodies mediated immunoassay may provide potential applications in a general method for the ultrasensitive detection of various cancer biomarkers.


Subject(s)
Single-Domain Antibodies/immunology , alpha-Fetoproteins/analysis , Animals , Camelids, New World , Cell Surface Display Techniques , Enzyme-Linked Immunosorbent Assay , Humans , Male , Polymerase Chain Reaction , Reproducibility of Results , Serum/chemistry , alpha-Fetoproteins/immunology
10.
Anal Bioanal Chem ; 408(3): 895-903, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26608283

ABSTRACT

A nanobody (N-28) which can act as a deoxynivalenol (DON) antigen has been generated, and its residues Thr102-Ser106 were identified to bind with anti-DON monoclonal antibody by alanine-scanning mutagenesis. Site-saturation mutagenesis was used to analyze the plasticity of five residues and to improve the sensitivity of the N-28-based immunoassay. After mutagenesis, three mutants were selected by phage immunoassay and were sequenced. The half-maximal inhibitory concentrations of the immunoassay based on mutants N-28-T102Y, N-28-V103L, and N-28-Y105F were 24.49 ± 1.0, 51.83 ± 2.5, and 35.65 ± 1.6 ng/mL, respectively, showing the assay was, respectively, 3.2, 1.5, and 2.2 times more sensitive than the wild-type-based assay. The best mutant, N-28-T102Y, was used to develop a competitive phage ELISA to detect DON in cereals with high specificity and accuracy. In addition, the structural properties of N-28-T102Y and N-28 were investigated, revealing that the affinity of N-28-T102Y decreased because of increased steric hindrance with the large side chain. The lower-binding-affinity antigen mimetic may contribute to the improvement of the sensitivity of competitive immunoassays. These results demonstrate that nanobodies would be a favorable tool for engineering. Moreover, our results have laid a solid foundation for site-saturation mutagenesis of antigen-mimicking nanobodies to improve immunoassay sensitivity for small molecules.


Subject(s)
Antigens/chemistry , Immunoassay/instrumentation , Single-Chain Antibodies/chemistry , Single-Chain Antibodies/genetics , Trichothecenes/chemistry , Antigens/genetics , Antigens/immunology , Immunoassay/methods , Molecular Mimicry , Mutagenesis , Single-Chain Antibodies/immunology , Trichothecenes/genetics , Trichothecenes/immunology
11.
Anal Chim Acta ; 887: 201-208, 2015 Aug 05.
Article in English | MEDLINE | ID: mdl-26320803

ABSTRACT

In this study, using mycotoxin deoxynivalenol (DON) as a model hapten, we developed a nanobody-based environmental friendly immunoassay for sensitive detection of DON. Two nanobodies (N-28 and N-31) which bind to anti-DON monoclonal antibody (MAb) were isolated from a naive phage display library. These nanobodies are clonable, thermally stable and mycotoxin-free products and can be served as coating antigen mimetics in heterologous immunoassay. The half inhibition concentration (IC50) of the immunoassay developed with N-28 and N-31 was 8.77 ± 0.41 ng mL(-1) and 19.97 ± 0.84 ng mL(-1), respectively, which were 18- and 8-fold more sensitive than the conventional coating antigen (DON-BSA) based immunoassay. In order to better understand the molecular mechanism of antigen mimicry by nanobody, the 3D structure of "nanobody (N-28) - anti-DON MAb" complex was presented and verified by molecular modeling and alanine-scanning mutagenesis. The results showed that hydrogen bond and hydrophobic interaction formed between Thr 102 - Ser 106 of N-28 and CDR H3 residues of anti-DON antibody may contribute to their binding. This novel concept of enhancing sensitivity of immunoassay for DON based on nanobody may provide potential applications in a general method for immunoassay of various food chemical contaminants.


Subject(s)
Edible Grain/microbiology , Immunoassay/methods , Mycotoxins/analysis , Single-Domain Antibodies/chemistry , Trichothecenes/analysis , Amino Acid Sequence , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/immunology , Enzyme-Linked Immunosorbent Assay/methods , Haptens/analysis , Haptens/immunology , Molecular Docking Simulation , Molecular Mimicry , Molecular Sequence Data , Mycotoxins/immunology , Peptide Library , Single-Domain Antibodies/immunology , Trichothecenes/immunology
12.
Article in English | MEDLINE | ID: mdl-25482072

ABSTRACT

Citrinin, a fungal secondary metabolite of polyketide origin, is moderately nephrotoxic to vertebrates, including humans. Citrinin is synthesised by condensation of acetyl-CoA and malonyl-CoA. Six genes involved in the citrinin biosynthesis, including pksCT, ctnA and ctnB, have been cloned in Monascus purpureus. The pksCT gene encodes a polyketide synthase; ctnA is a regulatory factor; and ctnB encodes an oxidoreductase. When the three genes were respectively disrupted, the disruption strains drastically decreased citrinin production or barely produced citrinin. Ten new genes have been discovered in Monascus aurantiacus besides the above six genes. One of these gene displayed the highest similarity to the ß-carbonic anhydrase gene from Aspergillus oryzae (74% similarity) and was designated ctnG. To learn more about the citrinin biosynthetic pathway, a ctnG-replacement vector was constructed to disrupt ctnG with the hygromycin resistance gene as the selection marker, then transformed into M. aurantiacus Li AS3.4384 by a protoplast-PEG method. The citrinin content of three disruptants was reduced to about 50%, meanwhile pigment production decreased by 23%, respectively, over those of the wild-type strains. ctnG was deduced to be involved in the formation of malonyl-CoA as a common precursor of red pigments and citrinin. Therefore, the disruption of the ctnG gene decreased citrinin and pigment production. M. aurantiacus Li AS3.4384 can produce higher concentrations of citrinin than other strains such as M. purpureus and M. ruber. Establishing the function of citrinin biosynthetic genes in M. aurantiacus is helpful in understanding the citrinin synthetic pathway and adopting some strategies to control contamination.


Subject(s)
Carbonic Anhydrases/genetics , Citrinin/biosynthesis , Fungal Proteins/genetics , Monascus/enzymology , Carbonic Anhydrases/metabolism , DNA, Fungal/genetics , Escherichia coli/genetics , Escherichia coli/metabolism , Fungal Proteins/metabolism , Monascus/genetics , Pigments, Biological/biosynthesis
13.
Anal Chem ; 86(16): 8433-40, 2014 Aug 19.
Article in English | MEDLINE | ID: mdl-25052468

ABSTRACT

Here, on the basis of mimotope of small analytes, we demonstrated a new approach for development of sensitive and environmentally friendly immunoassay for toxic small analytes based on the peptide-MBP fusion protein. In this work, using mycotoxin fumonisin B1 (FB1) as a model hapten, phage displayed peptide (mimotope) that binds to the anti-FB1 antibody were selected by biopanning from a 12-mer peptide library. The DNA coding for the sequence of peptide was cloned into Escherichia coli ER2738 as a fusion protein with a maltose binding protein (MBP). The prepared peptide-MBP fusion protein are "clonable" homogeneous and FB1-free products and can be used as a coating antigen in the immunoassay. The half inhibition concentration of the quantitative immunoassay setup with fusion protein (F1-MBP and F15-MBP) was 2.15 ± 0.13 ng/mL and 1.26 ± 0.08 ng/mL, respectively. The fusion protein (F1-MBP) was also used to develop a qualitative Elispot assay with a cutoff level of 2.5 ng/mL, which was 10-fold more sensitive than that measured for chemically synthesized FB1-BSA conjugates based Elispot immunoassay. The peptide-MBP fusion protein not only can be prepared reproducibly as homogeneous and FB1-free products in a large-scale but also can contribute to the development of a highly sensitive immunoassay for analyzing FB1. Furthermore, the novel concept might provide potential applications to a general method for the immunoassay of various toxic small molecules.


Subject(s)
Fumonisins/analysis , Immunoassay/methods , Maltose-Binding Proteins/chemistry , Mycotoxins/analysis , Peptides/chemistry , Amino Acid Sequence , Animal Feed/analysis , Animal Feed/microbiology , Cloning, Molecular , Escherichia coli/genetics , Limit of Detection , Maltose-Binding Proteins/genetics , Oryza/chemistry , Oryza/microbiology , Peptide Library , Peptides/genetics , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Zea mays/chemistry , Zea mays/microbiology
14.
Anal Chem ; 85(21): 10304-11, 2013 Nov 05.
Article in English | MEDLINE | ID: mdl-24099401

ABSTRACT

With the advantage of replacing mycotoxins and their conjugates, mimotopes have been applied to immunoassays, the most common of which were seleted from random phage displayed peptide libraries. However, these mimotopes were limited by the diversities of the peptide libraries. The aim of this study was to demonstrate that a variety of mimotopes can be obtained by constructing a second-generation peptide library. Using mycotoxin ochratoxin A as a model system, a dodecapeptide mimotope was isolated after panning the second-generation peptide library. The half inhibition concentration of the chemiluminescent enzyme-linked immunosorbent assay setup with this mimotope was 0.04 ng/mL, and the linear range was 0.006-0.245 ng/mL. The mimotope was also used to develop a qualitative dipstick assay with a cutoff level of 1 ng/mL. The method not only presents a high sensitivity but also contributes to the development of mimotope-based assays for mycotoxins avoiding the need of synthesizing toxic mycotoxin conjugates.


Subject(s)
Enzyme-Linked Immunosorbent Assay/methods , Mycotoxins/chemistry , Ochratoxins/chemistry , Peptide Library , Amino Acid Sequence , Base Sequence , Luminescence , Molecular Sequence Data
15.
J Agric Food Chem ; 61(30): 7397-402, 2013 Jul 31.
Article in English | MEDLINE | ID: mdl-23841779

ABSTRACT

The filamentous fungi Monascus spp. have been used in the production of food colorants and health remedies for more than 1000 years in Asia. However, greater attention has been given to the safety of Monascus products because they contain citrinin, which is harmful to the hepatic and renal systems. The citrinin biosynthetic gene cluster has been characterized in Monasucs aurantiacus . The ctnB gene encoding an oxidoreductase is located between pksCT and ctnA. In this study, a ctnB replacement vector (pCTNB-HPH) was constructed to disrupt the ctnB gene with a hygromycin resistance gene as the selection marker. The linear vector was transformed into M. aurantiacus using the protoplast CaCl2/polyethylene glycol (PEG) method. Three ctnB-disrupted strains were obtained by homologous recombination. In comparison to the parental strain, the ΔctnB mutants barely produced citrinin. These data confirmed that the ctnB gene is directly involved in citrinin biosynthesis. Moreover, the yields of the pigments of two disruptants were similar to that of the wild-type strain, but the yield of another mutant was slightly higher than that of the latter strain. These results indicate that the production of the mycotoxin citrinin was successfully eliminated through genetic engineering.


Subject(s)
Citrinin/biosynthesis , Fungal Proteins/genetics , Gene Silencing , Monascus/genetics , Mycotoxins/biosynthesis , Fungal Proteins/metabolism , Monascus/enzymology , Monascus/metabolism , Multigene Family , Oxidoreductases/genetics , Oxidoreductases/metabolism
16.
J Agric Food Chem ; 61(20): 4765-70, 2013 May 22.
Article in English | MEDLINE | ID: mdl-23692446

ABSTRACT

Anti-fumonisin B(1) (FB(1)) McAb 1D11 was used as the target for biopanning from a phage random loop-constrained heptapeptide library. After three cycles of panning, seven phages with three mimotope peptides were selected to mimic the binding of FB(1) to 1D11. After the identification of phage ELISA, the phage clone that showed the best linear range of detection was chosen for further research. One peptide with the inserted peptide sequence of the phage was synthetized, named CT-452. An indirect competitive ELISA (peptide ELISA) for detecting FB(1) was established using the CT-452-bovine serum albumin conjugate as coating antigen. The linear range of the inhibition curve was 1.77-20.73 ng/mL. The half inhibitory concentration (IC50) was 6.06 ng/mL, and the limit of detection was 1.18 ng/mL. This method was compared with conventional indirect ELISA (commercial ELISA kit) and high-performance liquid chromatography (HPLC), and the results showed the reliability of the peptide ELISA for the determination of FB(1) in cereal samples. The relationship between the CT-452 and FB(1) standard concentrations in peptide ELISA was evaluated. The results indicated that synthetic peptide CT-452 can replace the FB(1) standard to establish an immunoassay free of FB(1).


Subject(s)
Enzyme-Linked Immunosorbent Assay/methods , Fumonisins/analysis , Fumonisins/chemistry , Peptides/immunology , Antibodies, Monoclonal , Chromatography, High Pressure Liquid , Edible Grain/chemistry , Food Contamination/analysis , Fumonisins/immunology , Molecular Mimicry , Peptide Library , Peptides/chemistry , Reproducibility of Results
17.
Chin J Traumatol ; 15(6): 323-8, 2012.
Article in English | MEDLINE | ID: mdl-23186919

ABSTRACT

OBJECTIVE: To explore the changes of Treg-Th17 balance influenced by corticosterone, major effect hormone of hypothalamic-pituitary-adrenal (HPA) axis under running stress. METHODS: A total of 25 corticotropin-releasing hormone (CRH) wildtype (CRH+/+) and knockout (CRH-/-) mice were adopt and divided into 4 groups as follows: CRH+/+ ctrl, CRH+/+ stress, CRH-/- ctrl and CRH-/- stress. All mice in stress groups were under 2 h running. After 1 h, blood plasma in all groups was collected and the expression of corticosterone and IL-17A was detected by ELISA. Meanwhile, unicell suspensions of peripheral lymph node and spleen in each group were prepared too and stained by PE-CD4 and FITC-CD25, then the changes of Treg (CD4+CD25+) in different groups were checked by flow cytometry; all data were statistically analyzed by the software of WinMDI 2.9, SPSS 11.5, Origin 7.5 and Matlab 2-D and 3-D plot function. RESULTS: The levels of corticosterone were significantly higher in stress groups than that in corresponding control groups (P less than 0.05), especially in CRH+/+ stress group (P less than 0.01). However, the changes of Tregs were not obvious between stress groups and control groups with respective genotypes (P less than 0.05). Compared with that in CRH+/+ control group, the ratio of Treg and the expression of IL-17A in CRH-/- stress group were significantly higher than those in control group (P less than 0.05). Combined with the expression levels of corticosterone, Treg and Th17, our study suggests that endogenous glucocorticoid with basal level may cause the changes in Treg-Th17 balance. Moreover, as the corticosterone level increases, the expression of Treg and Th17 appears to manifest antagonistic fluctuant status with a rising tendency in general. CONCLUSION: Endogenous glucocorticoid under early stage of stress may increase the function of T lymphocyte immunity to some extent.


Subject(s)
CD4 Antigens/metabolism , Corticosterone/blood , Interleukin-17/metabolism , Interleukin-2 Receptor alpha Subunit/metabolism , Stress, Physiological , Th17 Cells/metabolism , Animals , Corticotropin-Releasing Hormone/metabolism , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Lymph Nodes/cytology , Mice , Mice, Knockout , Pituitary-Adrenal System/metabolism , Running/physiology , Spleen/cytology
18.
Zhonghua Bing Li Xue Za Zhi ; 41(10): 676-80, 2012 Oct.
Article in Chinese | MEDLINE | ID: mdl-23302309

ABSTRACT

OBJECTIVE: To study the clinicopathological features of diabetic microangiopathy in liver and diabetic hepatosclerosis (DHS) of elderly male with type 2 diabetes mellitus (T2DM). METHODS: One hundred and twenty autopsy cases with T2DM (diabetic group) and contemporary 48 cases, non-diabetic and glucose tolerance abnormal, matched by gender and age (control group) were selected in the study. Cases with the cirrhosis and fibrosis of liver caused by other foregone etiological factors were excluded. The histopathological changes of microangiopathy in liver, hepatic portal areas and hepatic sinusoid were investigated by HE staining, histochemical and immunohistochemical stain methods. The clinical data of diagnostic DHS cases were analyzed. RESULTS: (1) Microangiopathy was observed in 54.2% (65/120) cases of diabetic group. Histological features: microangiopathy was found in interlobular arteries (especially in arteriole, the lumen diameter < 100 µm), which included endothelial denudation, eosinophilic material deposition in the tunica intima of artery, and eccentric intimal thickening. The smooth muscle fibers of tunica media were hyperplastic or atrophy. Fibroplasia and collagen deposition were found in the tunica adventitia of artery. Arterial lumina showed stenosis and occlusion. Microangiopathy was seen in 16.7% (8/48) cases of the control group. There was statistically significant difference between the two groups (χ(2) = 19.622, P < 0.01). (2) The fibrosis and sclerosis of portal areas were detected in 55.8% (67/120) cases of T2DM group. Hyaline collagen fiber tissues was deposited around interlobular arteries, interlobular veins and interlobular bile ducts, resulting in enlargement of the portal area and the secondary atrophy and disappearance of portal triad. The fibrosis and sclerosis of portal areas were detected in 22.9% (11/48) cases of the control group. There was a statistically significant difference between the two groups (χ(2) = 14.936, P < 0.01). (3) The pathological features of 14.2% (17/120) cases were consistent with the diagnosis of DHS. The fibrous tissue extended from fibrosis or sclerosis of portal areas, or eosinophilic material deposition in the hepatic sinusoid in non-zonal pattern. The results of histochemical staining showed collagen fiber deposition in hepatic sinusoid. Stainings for Collagen IV, SMA, CD34 were found in the hepatic sinusoid. The sclerosis of hepatic sinusoid was not detected in any case in the control group.Overall, 13/17 and 11/17 DHS cases had liver microangiopathy and portal areas sclerosis respectively. Diabetic nephropathy was seen in 10 of 17 DHS cases. Among the 17 cases, 7 cases showed ALP elevation, of which there were 3 cases with ALT and AST mild elevation. CONCLUSIONS: Diabetic microangiopathy is common in the liver of elderly men with T2DM. And DHS is associated with diabetic microangiopathy. Fibrosis and sclerosis of portal areas may be the early or concomitant changes of DHS on histological ground. DHS is one of the complications of T2DM.


Subject(s)
Diabetes Mellitus, Type 2/complications , Diabetic Angiopathies/pathology , Liver Cirrhosis/complications , Liver/pathology , Actins/metabolism , Aged , Aged, 80 and over , Alanine Transaminase/blood , Alkaline Phosphatase/blood , Antigens, CD34/metabolism , Aspartate Aminotransferases/blood , Collagen Type IV/metabolism , Diabetic Angiopathies/blood , Diabetic Angiopathies/etiology , Diabetic Angiopathies/metabolism , Diabetic Nephropathies/complications , Diabetic Nephropathies/pathology , Humans , Liver/blood supply , Male , Middle Aged , Sclerosis
19.
Huan Jing Ke Xue ; 33(12): 4194-204, 2012 Dec.
Article in Chinese | MEDLINE | ID: mdl-23379142

ABSTRACT

Wetland reclamation and aquaculture is one of the main disturbance types in coastal wetlands. Diurnal variations of CO2, CH4 and N2O fluxes at the water-air interface were determined using a floating chambers + gas chromatography method in a shrimp pond, and a mixed culture pond of fish and shrimp in October in the Shanyutan Wetland of the Min River estuary, southeast China. Meanwhile, the meteorological indicators in ground surface and physical, chemical and biological indicators of surface water were also measured. CO2, CH4 and N2O fluxes at the water-air interface all demonstrated distinct diurnal variations. Both shrimp pond and mixed culture pond of fish and shrimp functioned as a sink of CO2 [the diurnal averaged CO2 fluxes were -48.79 and -105.25 mg x (m2 x h)(-1), respectively], and a source of CH4 [the diurnal averaged CH4 fluxes were 1.00 and 5.74 mg x (m2 x h)(-1), respectively]; the diurnal averaged CO2 and CH4 fluxes at the water-air interface of the mixed culture of fish and shrimp pond were higher than that of the shrimp pond. Greenhouse gas fluxes at the water-air interface from the aquaculture ponds were influenced by many factors. Multiple stepwise regression analysis showed that the concentration of Chlorophyll was the major factor affecting the CO2 fluxes, and the concentrations of SO4(2-) and PO4(3-) were the major factors affecting the CH4 fluxes at the water-air interface of the shrimp pond; whereas water temperature and Chlorophyll were the major factors affecting the CO2 fluxes, and dissolved oxygen, PO4(3-) and pH were the major factors affecting the CH4 fluxes at the water-air interface of the mixed culture pond of fish and shrimp.


Subject(s)
Air Pollutants/analysis , Aquaculture/methods , Carbon Dioxide/analysis , Estuaries , Greenhouse Effect , China , Environmental Monitoring , Methane/analysis , Nitrous Oxide/analysis , Oceans and Seas , Rivers , Wetlands
20.
Regul Toxicol Pharmacol ; 59(2): 324-33, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21129430

ABSTRACT

To investigate the chronic toxicity of cyadox, a growth promoting agent, five groups of Wistar rats (30 rats/group/sex) were fed with the diets containing cyadox (0, 100, 400 and 2000 mg/kg) or olaquindox (400 mg/kg) for 78weeks. There were significant decreases in body weights in both genders during most of the study period in 2000 mg/kg cyadox and 400 mg/kg olaquindox rats. Significant decreases in serum alkaline aminotransferase in the 2000 mg/kg cyadox rats at weeks 26, 52 and 78 were observed. Relative weights of liver and kidney were significantly increased in 2000 mg/kg cyadox and 400 mg/kg olaquindox rats at weeks 26, 52 and 78. A significant increase in relative brain and heart weights in 2000 mg/kg cyadox males was observed. The histopathological examinations revealed that 2000 mg/kg cyadox diet or 400 mg/kg olaquindox diet could induce proliferation of bile canaliculi in the portal area of liver and swelling and fatty degeneration of the proximal renal tubular epithelial cells in kidneys. In conclusion, the target organs of cyadox for rats were liver and kidney. The no-observed-adverse-effect level of cyadox in this study was estimated to be 400 mg/kg diet.


Subject(s)
Quinoxalines/toxicity , Animals , Body Weight/drug effects , Eating/drug effects , Female , Kidney/drug effects , Liver/drug effects , Male , No-Observed-Adverse-Effect Level , Organ Size/drug effects , Quinoxalines/administration & dosage , Random Allocation , Rats , Rats, Wistar , Toxicity Tests, Chronic/methods , Transaminases/blood
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