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In Arabidopsis, systemic acquired resistance (SAR) is established beyond the initial infection by a pathogen or is directly induced by treatment with salicylic acid (SA) or its functional analogs, 2,6-dichloroisonicotinic acid (INA) and benzothiadiazole (BTH). NPR1 protein is considered the master regulator of SAR in both SA signal sensing and transduction. In wheat (Triticum aestivum) and barley (Hordeum vulgare), both pathogen infection and BTH treatment can induce broad-spectrum resistance to various diseases, including powdery mildew, leaf rust, Fusarium head blight, etc. However, three different types of SAR-like responses including acquired resistance (AR), systemic immunity (SI), and BTH-induced resistance (BIR) seem to be achieved by activating different gene pathways. Recent research on wheat and barley NPR1 homologs in AR and SI has provided the initial clue for understanding the mechanism of SAR in these two plant species. In this review, the specific features of AR, SI, and BIR in wheat and barley were summarized and compared with that of SAR in model plants of Arabidopsis and rice. Research updates on downstream genes of SAR, including pathogenesis-related (PR) and BTH-induced genes, were highlighted.

The effect of long-term fertilization on soil denitrifying communities was analysed by measuring the abundance and diversity of the nitrous oxide (N2O) reductase gene, nosZ. Soil samples were collected from plots of a long-term fertilization experiment established in 1982 in Suining City, China. The fertilizer treatments were no fertilizer (CK), three chemical fertilizer (CF) treatments (N, NP, NPK), manure (M) alone, and manure with chemical fertilizers (NM, NPM, NPKM). The abundance and diversity of the denitrifying bacteria were assessed by real-time quantitative PCR, terminal restriction fragment length polymorphism (T-RFLP), and cloning and sequencing of nosZ genes. The diversity and abundance of nosZ-denitrifiers was higher in soil amended with manure and chemical fertilizers (CFM) than in soil amended with CF alone, and the highest in topsoil (0–20 cm). The nosZ-denitrifier community composition was more complex in CFM soil than in CF soil. Specific species were detected only in the CFM soil. The abundance of nosZ-denitrifier in the NPKM treatment was approximately two times higher than that in the CK, N, and NPK treatments. Most of the cloned nosZ sequences were closely related to nosZ sequences from Bradyrhizobiaceae and Rhodospirillaceae in Alphaproteobacteria. Of the measured abiotic factors, soil organic matter correlated significantly with the abundance (P

Objective Alkaline phosphatase (ALP) serves as a biomarker for diagnosing several types of diseases in adults; nonetheless, its use is restricted in children because of changes in ALP activity during different physiological phases. The present study aimed to investigate ALP activity and its dynamics in children of different ages to establish the reference values for ALP activity in children. Methods Total 167,625 samples of children aged 0–18 years were enrolled in this study. ALP activity was measured using the 4-nitrophenyl-1-phosphate disodium salt (4-NPP)–2-amino-2-methyl-1-propanol (AMP) method with an automatic biochemical analyzer. Patients with known diagnoses that may affect ALP activity were excluded. A percentile curve was plotted using MATLAB software, and the curve was fitted using the skewness–median–coefficient of variation (LMS) method. Results ALP activity reached the highest peak at 12–13 years of age and then gradually decreased to the lowest peak at 18–19 years of age in boys, whereas it reached the highest at 10–11 years and then gradually reduced to the lowest at 17–18 years in girls. Furthermore, the highest peak of ALP activity appeared substantially earlier in children of either sex in China than in those in Germany. Conclusions We showed the dynamics of ALP activity in both boys and girls between the ages of 0 and 18 years in China and compared the difference in ALP activity between children in China and Germany. Our findings provide a reference for clinicians.

UNLABELLED Soy isoflavone metabolites are currently receiving much attention due to the stronger and wider bioactivities than that of isoflavones. Therefore, biosynthesis of isoflavone metabolites by isolated isoflavone biotransforming bacteria is important. However, the biosynthesis process must be under obligate anaerobic conditions due to the reduction reactions catalysed by isoflavone biotransforming bacteria. In this study, we cloned the daidzein and genistein reductase gene (dgr) from Slackia sp. AUH-JLC159. The recombinant Escherichia coli (E. coli) whole-cell was used for the first time as the biocatalyst for aerobic biosynthesis of dihydrodaidzein (DHD) and dihydrogenistein (DHG) from soy isoflavones daidzein and genistein. Our results indicated that the recombinant E. coli whole-cell was able to reduce daidzein and genistein to DHD and DHG under aerobic conditions, while the maximal concentration of the substrate daidzein or genistein that the E. coli whole-cell was able to convert efficiently was only 0·4 mmol l(-1) . Under the optimized conditions, the maximal concentration of daidzein or genistein that the E. coli whole-cell was able to convert efficiently was increased to 1·4 mmol l(-1) . Our results demonstrated that E. coli whole-cell is an efficient biocatalyst for biosynthesis of isoflavone metabolites under aerobic conditions. SIGNIFICANCE AND IMPACT OF THE STUDY Soy isoflavone metabolites, which are more biologically active than their precursor isoflavones, are currently receiving much more attention. However, the non-natural isoflavone metabolites are synthesized or biosynthesized under obligate anaerobic conditions. Here, we describe a new approach to the reduction of soy isoflavones daidzein and genistein under aerobic conditions by use of the recombinant Escherichia coli whole-cell expressing isoflavone reductase. Our study provides the first evidence that isoflavone metabolites, such as dihydrodaidzein and dihydrogenistein, are able to be produced efficiently under aerobic conditions.

Anodized composite films containing SiC nanoparticles were synthesized on Ti6Al4V alloy by anodic oxidation procedure in C4O6H4Na2 electrolyte. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) were employed to characterize the morphology and composition of the films fabricated in the electrolytes with and without addition of SiC nanoparticles. Results show that SiC particles can be successfully incorporated into the oxide film during the anodizing process and preferentially concentrate within internal cavities and micro-cracks. The ball-on-disk sliding tests indicate that SiC-containing oxide films register much lower wear rate than the oxide films without SiC under dry sliding condition. SiC particles are likely to melt and then are oxidized by frictional heat during sliding tests. Potentiodynamic polarization behavior reveals that the anodized alloy with SiC nanoparticles results in a reduction in passive current density to about 1.54×10−8 A/cm2, which is more than two times lower than that of the TiO2 film (3.73×10−8 A/cm2). The synthesized composite film has good anti-wear and anti-corrosion properties and the growth mechanism of nanocomposite film is also discussed.

The hypersensitive response (HR) is one of the most-efficient forms of plant defense against biotrophic pathogens. However, the molecular mechanisms leading to HR remain largely unknown. A putative hypersensitive-induced response (HIR) protein gene TaHIR4 cDNA (919 bp) and a DNA sequence (2520 bp) including at least five exons were isolated and identified from wheat. Phylogenetic analysis showed that TaHIR4 was highly homologous to HvHIR4 from barley at both the cDNA and deduced amino-acid levels. Reverse transcription quantitative polymerase chain reaction (qRT-PCR) results showed that TaHIR4 transcripts were highly upregulated by infection of the leaf rust pathogen and expressed in all tested samples except the mature seeds. Western blotting results also showed that TaHIR4 protein was upregulated in wheat leaves infected with the leaf rust pathogen. Characterization and expression profiles at the gene and protein levels suggested that TaHIR4 plays a role in wheat HR, caused by the leaf rust pat...

Hypersensitive-induced reaction (HIR) proteins and more specific members of the proliferation, ion and death superfamily participate in response to pathogen attacks and development of spontaneous hypersensitive lesions in maize and barley leaves. In the present study, a full-length TaHIR3 (1,246-bp) was cloned and characterized from wheat near-isogenic line Thatcher-Lr15 infected by Puccinia triticina isolate 05-19-43② through a homology cloning strategy. A 4,203-bp sequence of TaHIR3 including five exons was also obtained from wheat Thatcher-Lr15 genomic DNA. TaHIR3 shared higher similarity with HIR3 isolated from wheat, barley, and maize. Gene expression of TaHIR3 was spatially measured in young wheat leaves, young roots, young stems, mature seeds, and temporally in wheat leaves inoculated with virulent and avirulent P. triticina. TaHIR3 was expressed in all samples except mature seeds and was upregulated in both combinations. More transcripts accumulated in the incompatible than compatible combination, implying a role in wheat growth and resistance to pathogens attack. A polyclonal antibody was prepared with recombinant protein purified from a prokaryotic expression system with the open reading frame of TaHIR3, and it detected the target protein in wheat leaves by Western blotting. Detection results at the protein level also showed that TaHIR3 was upregulated expression in wheat leaves infected with the leaf rust pathogen. Characterization of TaHIR3 and its expression profiles at the DNA and protein levels suggest that TaHIR3 and its deduced protein play a role in wheat HR causing by the leaf rust pathogen.

Hypersensitive induced reaction (HIR) protein had been reported to play roles in plant resisting biotic and abiotic stress. In this study, a full length cDNA TaHIR2 , encoding a 284- amino-acid protein with deduced MW of 31.34 kDa and predicted pI of 5.42, was cloned and identified from wheat leaves infected by leaf rust pathogen. The amino acid sequence deduced from TaHIR2 shared 99% homology with HvHIR2 from barley and contained prohibitins-domain which is a member of SPFH protein domain. Temporal expression profiles indicated that the TaHIR2 transcripts in the incompatible and compatible interactions begun to increase at 18 h post-inoculation (hpi), and reached the maximum at 36 hpi, then declined, but the relative expression of TaHIR2 transcripts in the incompatible interaction was 4.11 and 1.32 times higher than that in compatible one at 24 and 36 hpi, respectively. The accumulation of TaHIR2 transcript was the highest in wheat leaf. Furthermore, Western blot showed that the maximum accumulation of the TaHIR2 at the protein level occurred at 60 and 96 hpi in the incompatible and compatible interactions, respectively. Based on the above results, we primarily concluded that a novel TaHIR2 gene was successfully cloned from wheat and may play a role in wheat resistant to the leaf rust pathogen.

In order to reveal the cause of disease occurred in the process of Coptis chinensis growth, this paper studied the bacterial species diversity index of different aged rhizospheric and non-rhizospheric soil planting normal or sick C. chinensis by using PCR-DGGE technique. The representative DGGE bands were chosen to be cloned, and sequenced, the phylogeny were constructed. The results showed that the bacterial communities were very different between the normal and diseased soil samples of C. chinensis, and the diversity index (H) of diseased soil samples were higher than that of normal soil samples. Sequencing analysis of representative cloned DGGE bands showed that the unculturable bacteria were the dominant groups, and bacteria belonged to genus Bacillus, Acidovorax, Acinetobacter, uncultured Kluyvera, and uncultured Comamonas were also existing, but the reported plant pathogenic bacteria were not found in the C. chinensis planting soil. The density and brightness of clone band d in diseased soil samples was higher than that in normal soil sample, and sequencing analysis showed that it belonged to genus Acidovorax. Obviously, during the process of C. chinensis growth, the rhizospheric bacteria population changed, and the quantity of bacteria belong Acidovorax increased, which probably resulted in the disease occurred during C. chinensis growth.

Having compared the sensational phenomena of the shock event of 1597 in the northeastern part of our country with that of the deep earthquakes of 1940, 1973, 1999, 2002 in the northeastern part of our country, we think that, the shock event of 1597 is a sensational deep earthquake.

Arctium lappa L. (A. lappa) is a popularly used vegetable as well as herbal medicine. Human intestinal microflora was reported to convert arctiin, the lignan compound with highest content in the dried fruits of Arctium lappa, to a series of metabolites. However, the specific bacterium responsible for the formation of 3'-desmethylarctigenin (3'-DMAG), the most predominant metabolite of arctiin by rat or human intestinal microflora, has not been isolated yet. In the present study, we isolated one single bacterium, which we named Blautia sp. AUH-JLD56, capable of solely biotransforming arctiin or arctigenin to (-)-3'-DMAG. The structure of the metabolite 3'-DMAG was elucidated by electrospray ionization mass spectrometry (ESI-MS) and (1)H and (13)C nuclear magnetic resonance spectroscopy. The biotransforming kinetics and maximum biotransforming capacity of strain AUH-JLD56 was investigated. In addition, the metabolite 3'-DMAG showed significantly higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity than that of the substrate arctigenin at the concentrations tested.

Currently, a large number of web sites are generated from web templates so as to improve the productivity of web sites construction. However, the prevalence of web templates has a negative impact on the efficiency of search engine in many aspects, including the relevance judgment of web IR and resource usage of analysis tool. In this paper, we present a direct and fast method to detect pages of the same template by DOM tree characteristics. After analyzing and compressing DOM tree nodes of the HTML page, our method generates a hash value digest, also called fingerprint, for each page to identify its DOM structure. In addition, we also introduce some other page features to aid in judging the page template type. Through experimental evaluations over thirty thousand sub-domains, we show that our approach can obtain the analysis results rapidly but with a high accuracy rate above 95 percents.

In spring 2004, potato scab disease was observed on potato tubers (Solanum tuberosum cv. Favorita) at approximately 5–10% incidence in fields in Shandong province, China. Scabby tubers had brown, superficial or pitted corky lesions that were somewhat different from typical symptoms (for example, superficial, raised or pitted lesions) of potato scab caused by Streptomyces scabies. Both traditional and PCR-based methods were employed to identify the causal agent. A Streptomyces sp. strain CPS-3 was isolated from the lesion of a scabby potato tuber on oatmeal agar. It produced rectiflexuous spore chains, and the spores were white with smooth surface and 0AE4–0AE5 · 0AE9–1AE1 lm in size. The strain did not produce melanin on tyrosine-peptone-yeast extract agar medium, but produced diffusible yellow pigments, utilized all the International Streptomyces Project (ISP) sugars as single carbon sources (Shirling & Gottlieb, 1966), and L-hydroxyproline, L-histidine as sole nitrogen sources but not L-methionine. It grew at pH 4AE0 and was susceptible to phenol (0AE1%) and crystal violet (0AE5 lg ⁄ mL), but not to penicillin (10 IU ⁄ mL) and streptomycin (20 lg ⁄ mL). It did not produce H2S. The 16S rRNA sequence of the strain was amplified using the primers S1 (5¢CATTCACGGAGAGTTTGATCC-3¢) and S2 (5¢-AGAAAGGAGGT GATCCAGCC-3¢). The resulting 1460 bp sequence (GenBank Accession No. AY621376) had the highest similarity (99AE8%) with S. acidiscabies type strainATCC 49003 (AB026220). The strain is identical to S. acidiscabiesbasedon theabovecharacteristics (LambertL Loria et al., 1997) but this is the first report of S. acidiscabies causing potato scab in China.