糖芯片制备和应用的最新研究进展

糖芯片是一种研究微量糖与生物大分子之间相互作用的生物检测技术,因其具有用量少、快速、高效和高通量等特点,现已被广泛应用到药物开发、免疫学,临床诊断和细菌检测等诸多领域中。近年来,尽管对糖芯片的制备方法和应用进行了较为深入的研究,但对糖芯片的制备方法和应用的综述还较少报道。本文主要介绍糖芯片的制备原理、非化学修饰和化学修饰制备糖芯片的最新方法,然后对糖芯片在自组装等方面应用的最新进展进行综述,并对糖芯片所遇到的挑战和发展趋势也作了展望。

Alteration of p53 and p21 during hepatocarcinogenesis in tree shrews

AIM: To investigate p53 mutation and p21 expression in hepatocarcinogenesis induced by hepatitis B virus (HBV) and aflatoxin B1 (AFB1) in tree shrews, and to reveal the role of these genes in hepatocarcinogenesis.METHODS: Tree shrews were divided into four groups:group A, those infected with HBV and fed with AFB1 (n = 39);group B, those infected with HBV alone (n = 28); group C,those fed with AFB1 alone (n = 29); and group D, normal controls (n = 20). The tree shrews underwent liver biopsies once every 15 wk. Expression of p53 and p21 proteins and genes in the biopsies and tumor tissues of the experimental tree shrews was detected, respectively, by immunohistochemistry,and by Southem blotting and reverse transcription-polymerase chain reaction and sequencing.RESULTS: The incidence of hepatocellular carcinomas (HCC) was higher in group A (66.7%) than that in group B (3.57%) and C (30%). The time of HCC occurrence was also earlier in group A than that in group C (120.0±16.6 wk vs 153.3±5.8 wk, respectively, P<0.01). p53 protein was not detected by immunohistochemistry in all groups before the 75^th wk of the experiment. At the 105^th wk, the positive rates fo p53 were 78.6%, 60% and 71.4% in groups A, B and C, respectively, which were significantly higher than that in group D (10%) (all P<0.05). An abnormal band of p53 gene was observed in groups A and C. The mutation points of p53gene in tree shrews with HCC were at codons 275, 78 and 13. The nucleotide sequence and amino acid sequence of tree shrew's wild-type p53 showed 91.7% and 93.4% homologies with those of human p53,respectively. The immunopositivity for p21 was found before HCC development. The incidence of HCC was significantly higher in tree shrews that were positive for p21 than those negative for p21 (80.0% vs 11.0%, P<0.001).The incidence of HCC in p21 positive animals in group A was significantly higher than those positive for p21 in group C (P<O.05).CONCLUSION: A remarkable synergistic effect on HCC development exists between HBV and AFB1. p53 mutation promotes the development of HCC. HBV and AFB1 may synergistically induce p53 gene mutation, and stimulate ras gene expression, ras gene is activated at the earlier stage during hepatocarcinogenesis, p21 protein may be an early marker, and the alterations of p53 may be a late event in the development of HCC.

Serum autotaxin levels are correlated with hepatic fibrosis and ballooning in patients with non-alcoholic fatty liver disease

AIM To examine the relationship between serum autotaxin(ATX) concentrations and clinicopathological findings in non-alcoholic fatty liver disease(NAFLD) patients.METHODS One hundred eighty-six NAFLD patients who had undergone liver biopsy between 2008 and 2017 were retrospectively enrolled.Serum samples were collected at the time of biopsy and ATX was measured by enzyme immunoassays.Sera obtained from 160 healthy,nonobese individuals were used as controls.Histological findings were graded according to an NAFLD scoring system and correlations with serum ATX were calculated by Spearman's test.Diagnostic accuracy was evaluated using the area under the receiver operating characteristic curve(AUC).Cut-off values were identified by the Youden index,and the nearest clinically applicable value to the cutoff was considered the optimal threshold for clinical convenience.RESULTS Serum ATX levels were significantly higher in NAFLD patients than in controls(0.86 mg/L vs 0.76 mg/L,P < 0.001) and correlated significantly with ballooning score and fibrosis stage(r = 0.36,P < 0.001 and r = 0.45,P < 0.001,respectively).Such tendencies were stronger in female patients.There were no remarkable relationships between ATX and serum alanine aminotransferase,lipid profiles,or steatosis scores.The AUC values of ATX for predicting the presence of fibrosis(≥ F1),significant fibrosis(≥ F2),severe fibrosis(≥ F3),and cirrhosis(F4),were all more than 0.70 in respective analyses.CONCLUSION Serum ATX levels may at least partially reflect histological severity in NAFLD.

New technologies accelerate the exploration of non-coding RNAs in horticultural plants

Non-coding RNAs(ncRNAs),that is,RNAs not translated into proteins,are crucial regulators of a variety of biological processes in plants.While protein-encoding genes have been relatively well-annotated in sequenced genomes,accounting for a small portion of the genome space in plants,the universe of plant ncRNAs is rapidly expanding.Recent advances in experimental and computational technologies have generated a great momentum for discovery and functional characterization of ncRNAs.Here we summarize the classification and known biological functions of plant ncRNAs,review the application of next-generation sequencing(NGS)technology and ribosome profiling technology to ncRNA discovery in horticultural plants and discuss the application of new technologies,especially the new genome-editing tool clustered regularly interspaced short palindromic repeat(CRISPR)/CRISPR-associated protein 9(Cas9)systems,to functional characterization of plant ncRNAs.

Polyphosphate and associated enzymes as global regulators of stress response and virulence in Campylobacter jejuni

Campylobacter jejuni(C. jejuni),a Gram-negative microaerophilic bacterium,is a predominant cause of bacterial foodborne gastroenteritis in humans worldwide. Despite its importance as a major foodborne pathogen,our understanding of the molecular mechanisms underlying C. jejuni stress survival and pathogenesis is limited. Inorganic polyphosphate(poly P) has been shown to play significant roles in bacterial resistance to stress and virulence in many pathogenic bacteria. C. jejuni contains the complete repertoire of enzymes required for poly P metabolism. Recent work in our laboratory and others have demonstrated that poly P controls a plethora of C. jejuni properties that impact its ability to survive in the environment as well as to colonize/infect mammalian hosts. This review article summarizes the current literature on the role of poly P in C. jejuni stress survival and virulence and discusses on how poly P-related enzymes can be exploited for therapeutic/prevention purposes. Additionally,the review article identifies potential areas for future investigation that would enhance our understanding of the role of poly P in C. jejuni and other bacteria,which ultimately would facilitate design of effective therapeutic/preventive strategies to reduce not only the burden of C. jejuni-caused foodborne infections but also of other bacterial infections in humans.

The grapevine kinome:annotation,classification and expression patterns in developmental processes and stress responses

Protein kinases(PKs)have evolved as the largest family of molecular switches that regulate protein activities associated with almost all essential cellular functions.Only a fraction of plant PKs,however,have been functionally characterized even in model plant species.In the present study,the entire grapevine kinome was identified and annotated using the most recent version of the grapevine genome.A total of 1168 PK-encoding genes were identified and classified into 20 groups and 121 families,with the RLK-Pelle group being the largest,with 872 members.The 1168 kinase genes were unevenly distributed over all 19 chromosomes,and both tandem and segmental duplications contributed to the expansion of the grapevine kinome,especially of the RLK-Pelle group.Ka/Ks values indicated that most of the tandem and segmental duplication events were under purifying selection.The grapevine kinome families exhibited different expression patterns during plant development and in response to various stress treatments,with many being coexpressed.The comprehensive annotation of grapevine kinase genes,their patterns of expression and coexpression,and the related information facilitate a more complete understanding of the roles of various grapevine kinases in growth and development,responses to abiotic stress,and evolutionary history.

The effects of glycyrrhizic acid and glabridin in the regulation of CXCL5 inflammation gene on acceleration of wound healing

Objective: To evaluate the anti-inflammatory property of both glycyrrhizic acid(GA)and glabridin in reducing inflammation to accelerate wound regeneration on 3T3-L1 and NIH-3T3 fibroblast cell lines.Methods: Cell proliferation and viability assay(MTT assay), scratch wound healing assays,and quantitative real-time PCR were conducted to investigate the effects on cell proliferation,cell migration, and expression of CXC chemokine ligand 5 inflammation gene respectively.Results: Results showed that at a low concentration of 1 × 10^(-8)mol/L, glabridin down regulated cell proliferation in NIH-3T3 significantly, suggesting its involvement in ERK1/2 signaling pathway. GA and glabridin significantly accelerated cell migration through wound healing in both 3T3-L1 and NIH-3T3 and significantly down regulated the expression of CXC chemokine ligand 5 in 3T3-L1 at concentration 1 × 10^(-8)mol/L,indicating the possible involvement of nuclear factor-k B and cyclooxygenase 2 transcriptions modulation.Conclusions: Both GA and glabridin can serve as potential treatment for chronic inflammatory disease, and glabridin as an oncogenic inhibitor due to its anti-proliferative property.

Biochemical Changes in Rat Lung during Acute Paraquat Intoxication

Paraquat (PQ) was administered intraperitoneally to male Wistar rats at a dose of 30 mg/kg.This dose caused mortality in 14% of the animals and significantly increased the lung wet weight by 28 and 93% at 2 and 3 days after treatment, respectively, compared to controls.The activity of several enzymes present in the lung was affected by PQ treatment.Pulmonary angiotensin-converting enzyme activity was significantly reduced at 4 h after PQ treatment and remained 32-36% below control levels during the following 3-day observation period.Alkaline phosphatase activity in the lung was significantly decreased by 26-33% at 1,2, and 3 days after PQ treatment.Lung glucose-6-phosphate dehydrogenase activity demonstrated a drop at 4 h, recovery to control levels at 1 day.and a subsequent rise to levels 45-55% higher than control levels at 2 and 3 days.Glutathione reductase activity in the lung decreased significantly by 21% at 2 and 3 days.These changes in enzyme activities, which may reflect effects on different cell populations of the lung and processes of damage and reparation, may prove to be useful as biochemical indicators of PQ toxicity.

Production of Endopolysaccharides from Malaysia’s Local Mushrooms in Air-Lift Bioreactor

Four local mushroom species, viz. Auricularis polytricha, Lentinus edodes, Agrocybe sp and Pleurotus flabellatus were grown under submerged culture and screened for endopolysaccharides. The fermentation was done in 250 ml working volume Erlenmeyer flask and the fermentation curves for all species were established. Pleurotus flabellatus has the highest rate of biomass production at the rate of 0.180 g/L/day, at 10 days hence chosen for further investigation. Two additional media, viz. Mushroom Complete Media (MCM) and Yeast Malt (YM) were selected to be compared with potato extract(PE) media used initially. MCM media produced the highest biomass productivity at the rate of 0.311 g/L/day. Pleurotus flabellatus biomass was extracted using modified Mizuno method and the endopolysaccharide obtained was tested for β-glucan. The yield of β-glucan was 7.70 ± 1.11 g/100g. The polysaccharides were purified using column chromatography to yield four fractions. The fourth fraction F4, gave the highest molecular weight at 3.058 × 106 Dalton (11.8%) and 1.282 × 104 Dalton (88.2%). The mushroom, P. flabbelatus was cultured using air-lift bioreactor, and the highest productivity was obtained at air-flowrate 2 L/min, yielding 2.25 g/L/day. The yield of biomass against substrate used (glucose consumption) Yb/s was 0.78 g/g.

Determination of bacterial viability by selective capture using surface-bound siderophores

A significant challenge in bacterial detection is the identification of viable bacteria over debris, specifically post decontamination. Of increasing concern are antibiotic resistant strains that require accurate and rapid post decontamination analysis. Current strategies are fraught with disadvantages and most of them are not selective for viable bacteria. However, bacteria are critically dependent upon iron sequestration, synthesizing and releasing siderophores (SDPs) to tightly bind iron, with the subsequent uptake of iron bound SDPs. This is a highly conserved process that occurs only in intact bacteria. Herein we report a facile method to use bacterial SDPs to selectively and rapidly identify only viable bacteria in complex matrices, and discriminate them from their dead counterparts. Desferrioxamine B (Desf B) tethered to a glass slide is used to specifically capture viable bacteria from a mixture of viable and dead Escherichia coli, as demonstrated by fluorescence microscopy. We re- port both direct conjugation of Desf B on thin-film-coated glass slides as well as biotin-streptavidin conjugation strategies, both of which are successful in the said goal. We have analyzed the density of images obtained upon fluorescence staining using edge detection with a Canny edge detector. This novel application of a software analysis tool originally developed for satellite imaging to biological staining allows for accurate quantitation of observed data.

Advances and perspectives in discovery and functional analysis of small secreted proteins in plants

Small secreted proteins(SSPs)are less than 250 amino acids in length and are actively transported out of cells through conventional protein secretion pathways or unconventional protein secretion pathways.In plants,SSPs have been found to play important roles in various processes,including plant growth and development,plant response to abiotic and biotic stresses,and beneficial plant–microbe interactions.Over the past 10 years,substantial progress has been made in the identification and functional characterization of SSPs in several plant species relevant to agriculture,bioenergy,and horticulture.Yet,there are potentially a lot of SSPs that have not been discovered in plant genomes,which is largely due to limitations of existing computational algorithms.Recent advances in genomics,transcriptomics,and proteomics research,as well as the development of new computational algorithms based on machine learning,provide unprecedented capabilities for genome-wide discovery of novel SSPs in plants.In this review,we summarize known SSPs and their functions in various plant species.Then we provide an update on the computational and experimental approaches that can be used to discover new SSPs.Finally,we discuss strategies for elucidating the biological functions of SSPs in plants.

Hydrogenation of Pyrolysis Oil from Loblolly Pine Residue

Loblolly pine residue prepared with and without zeolite ZSM-5 was pyrolyzed at 600℃ and the pyrolysis oil was hydrogenated using formic acid as a hydrogen source, in the presence of a Ru/activated carbon catalyst. As indicated by the pyrolysis yield, addition of the zeolite ZSM-5 increased the yield of light oil but decreased the yield of heavy oil. The pyrolysis oils were analyzed by 13C-,31P-,19F-nuclear magnetic resonance(NMR), and heteronuclear single quantum coherence or heteronuclear single quantum correlation nuclear magnetic resonance(HSQC-NMR), demonstrating that the zeolite ZSM-5 can efficiently induce decarboxylation reactions and decrease the content of aliphatic hydroxyl groups in the heavy oil by 57%.After hydrogenation of the pyrolysis oil, the aromatic carbon content decreased by 78%, with a significant increase in the aliphatic carbon content.

膜受体糖脂成分的结构和动态-~2H核磁共振为在体观察提供了途径

糖脂类普遍存在于大自然中,大脑中同样具有相当的数量。由于以往偏重于研究更引人注目的磷脂酰胆碱、乙醇氨及丝氨酸,人们相当程度上忽视了糖脂,现在我们终于认识到糖脂很可能在功能上比其它脂质具有更大的意义。在已知几个重要的过程中,它们关联到免疫应答、细胞间识别和激素接受。大脑中信号肽及调节蛋白质的受体无疑与这类糖脂或糖蛋白相当。

Disharmonious Ventricular Relationship and Topology for the Given Atrioventricular Connections.Contemporary Diagnostic Approach Using 3D Modeling and Printing

In the last issue,two case reports separately present examples of the extremely rare and complex congenital heart diseases that show concordant atrioventricular connections to the L-looped ventricles in the presence of situs solitus.Both cases highlight that the relationship between the two ventricles within the ventricular mass is not always harmonious with the given atrioventricular connection.Such disharmony between the connections and relationships requires careful assessment of the three basic facets of cardiac building blocks,namely their morphology,the relationship of their component parts,and their connections with the adjacent segments.3D imaging and printing can now facilitate an otherwise difficult diagnosis in such complex situations.Rotation of either the 3D images or the models permit accurate assessment of the ventricular topologic pattern by creating the right ventricular en-face septal view,thus facilitating placement of the observer’s hands.As we now emphasize,an alternative approach,which might prove more attractive to imagers,is to rotate the ventricular mass to provide the ventricular apical view,thus permitting determination of the ventricular relationship without using the hands.

Alteration of the p53 gene during tree shrews' hepatocarcinogenesis

OBJECTIVE: To detect the expression and variation of the p53 gene in hepatocarcinogenesis of tree shrews induced by hepatitis B virus (HBV) and aflatoxin B_1(AFB_1). METHODS: Tree shrews were divided into four groups: group A, infected with HBV and fed with AFB_1; group B, only infected with HBV; group C, fed with AFB_1 alone; and group D normal control. The tree shrews underwent liver biopsy every. 15 weeks. Liver and tumor tissues were detected by immunohistochemistry and molecular biotechnologies. RESULTS: The incidence of hepatocellular carcinoma (HCC) was higher in group A (66.7%) than in groups B (0) and C (30%). HCC occurrence was earlier in group A than in group C (120.0±16.6 wk vs 153.3±5.8 wk, t=3.336, P<0.01). Mutated p53 protein was not found in all groups before 75 weeks of experiment. At the 105th week, the expression rates of mutated p53 protein were 78.6%, 60.0% and 71.4% in groups A, B and C respectively, which were significantly higher than that in group D (10%) (X^2≥5.03, P<0.05). An abnormal band of the p53 gene was detected in groups A and C. The mutational points of the p53 gene in liver cancer of tree shrews were at codon 275, 78 and 13. Nucleotide sequence and amino acids sequence of tree shrew's wild-type p53 were 91.7% and 93.4% in homology, compared with those of human p53, respectively. CONCLUSIONS: Remarkable synergistic effect on HCC exists between HBV and AFB_1. Mutated p53 protein expressed before occurrence of HCC promotes the development of HCC. HBV and AFB_1 may synergistically induce p53 gene mutation.

Optimization of Mycelial Biomass Production in Submerged Culture Fermentation of <i>Pleurotus flabellatus</i>Using Response Surface Methodology

The factors selected to optimize the productivity of Pleurotus flabellatus biomass in 250ml working volume Erlenmeyer flask were agitation rate, initial pH value and incubation temperature. The central composite design was applied to study the significant factors and the interactions between the chosen factors, if present. The Design Expert software generated 20 runs. The optimized conditions obtained were as follows: the agitation rate of 129.8 rpm, incubation temperature at 27.8&degC, and initial pH of 6.06. The optimized conditions tripled the productivity at the range of 980 - 1040 mg/litre/day compared to the initial rate productivity at 310 mg/litre/day. From the quadratic equation,the agitation rate, temperature and the interaction between agitation rate and temperature were found to be significant (p < 0.05). At optimum conditions, the experimental data supported the theoretical estimate.

CRISPR/Cas9-based gene activation and base editing in Populus

The genus Populus has long been used for environmental,agroforestry and industrial applications worldwide.Today Populus is also recognized as a desirable crop for biofuel production and a model tree for physiological and ecological research.As such,various modern biotechnologies,including CRISPR/Cas9-based techniques,have been actively applied to Populus for genetic and genomic improvements for traits such as increased growth rate and tailored lignin composition.However,CRISPR/Cas9 has been primarily used as the active Cas9 form to create knockouts in the hybrid poplar clone“717-1B4”(P.tremula x P.alba clone INRA 717-1B4).Alternative CRISPR/Cas9-based technologies,e.g.those involving modified Cas9 for gene activation and base editing,have not been evaluated in most Populus species for their efficacy.Here we employed a deactivated Cas9(dCas9)-based CRISPR activation(CRISPRa)technique to fine-tune the expression of two target genes,TPX2 and LecRLK-G which play important roles in plant growth and defense response,in hybrid poplar clone“717-1B4”and poplar clone“WV94”(P.deltoides“WV94”),respectively.We observed that CRISPRa resulted in 1.2-fold to 7.0-fold increase in target gene expression through transient expression in protoplasts and Agrobacterium-mediated stable transformation,demonstrating the effectiveness of dCas9-based CRISPRa system in Populus.In addition,we applied Cas9 nickase(nCas9)-based cytosine base editor(CBE)to precisely introduce premature stop codons via C-to-T conversion,with an efficiency of 13%–14%,in the target gene PLATZ which encodes a transcription factor involved in plant fungal pathogen response in hybrid poplar clone“717-1B4”.Overall,we showcase the successful application of CRISPR/Cas-based technologies in gene expression regulation and precise gene engineering in two Populus species,facilitating the adoption of emerging genome editing tools in woody species.

GWAS identifies candidate genes controlling adventitious rooting in Populus trichocarpa

Adventitious rooting(AR)is critical to the propagation,breeding,and genetic engineering of trees.The capacity for plants to undergo this process is highly heritable and of a polygenic nature;however,the basis of its genetic variation is largely uncharacterized.To identify genetic regulators of AR,we performed a genome-wide association study(GWAS)using 1148 genotypes of Populus trichocarpa.GWASs are often limited by the abilities of researchers to collect precise phenotype data on a high-throughput scale;to help overcome this limitation,we developed a computer vision system to measure an array of traits related to adventitious root development in poplar,including temporal measures of lateral and basal root length and area.GWAS was performed using multiple methods and significance thresholds to handle non-normal phenotype statistics and to gain statistical power.These analyses yielded a total of 277 unique associations,suggesting that genes that control rooting include regulators of hormone signaling,cell division and structure,reactive oxygen species signaling,and other processes with known roles in root development.Numerous genes with uncharacterized functions and/or cryptic roles were also identified.These candidates provide targets for functional analysis,including physiological and epistatic analyses,to better characterize the complex polygenic regulation of AR.

食物-能源-水钮带关系研究能否与农业创新保持同步?

1.Introduction,The interconnection among food-energy-water(FEW)systems in meeting societal demands is broadly acknowledged[1].Similarly,competitive or synergistic allocations of water and energy resources for agricultural production,manufacturing,and human consumption are understood,and their economic impacts can be predicted[2].Far less appreciated and understood are the outcomes of the FEW nexus in response to operation changes in agricultural practices and the associated technological innovations for future generations[3,4].Also,the inter-scale and feedback effects of emerging technology-driven resource reallocation and decision-making on FEW systems are largely unknown.For example,how do the agroeconomic feedbacks of intelligent technologies influence the FEW nexus of agricultural production under environmental and demographic changes?How does the necessary water allocation for powering non-powered dams and pumped-storage hydropower generation influence agricultural production and municipal water supply maintenance?How do solar and wind energy farms influence land use for agriculture and the rural economy?

澳大利亚木虱在中国发生(英文)

Blastopsylla occidentalis Taylor是原产于澳大利亚的木虱种类,目前已经扩散到北美、南美、非洲、欧洲和亚洲。本文记述了B.occidentalis在中国的发生,并首次记录了其在澳大利亚以外的地区被寄生。这个种依赖于桉属Eucalyptus植物,其寄主超过20种,这可能是使其在世界范围扩散的一个重要因素。指出了B.occidentalis与桉树芽木虱Blastopsylla barbara Li为同种异名。