Genetic diversity of Venturia carpophila populations from different hosts and geographic regions in China.

Venturia carpophila, the causal agent of scab disease of peach, mume, and apricot, is widely distributed around the world. Scab of stone fruits is an important disease in China. However, little is known about the population biology and genetic diversity of the V. carpophila. To better understand the genetic diversity and population structure of V. carpophila, 186 single-spore isolates from different hosts and geographic regions were obtained and analyzed by using 31 simple sequence repeat (SSR) markers. This included 156 isolates from peach spanning 14 provinces, 15 isolates from mume and 15 isolates from apricot in Huazhong Agricultural University (HZAU). Diversity analysis with SSR markers showed a low incidence of polymorphisms within mume isolates (32.59% of markers), but a higher incidence of polymorphisms within peach isolates (42.96%) and apricot isolates (57.04%). Within peach isolates, Nei's average gene diversity ranged from 0.07 for Hebei population to 0.18 for Hubei population. AMOVA analysis revealed that 13% of the observed genetic diversity was partitioned among the geographic populations, while 40% of the observed genetic diversity was partitioned among the host populations. Other analyses (PCoA, STRUCTURE, DAPC, MSN, and UPGMA) indicated that the Chinese V. carpophila populations could be clustered into three distinct genetic groups, which correspond to the host boundaries of peach, mume and apricot. The genetic identity of V. carpophila isolates throughout the range is dependent on hosts, but not geographic regions.

Effect of Chemical Seed Treatment on Rice False Smut Control in Field.

Rice false smut, caused by the pathogen Ustilaginoidea virens, is a severe emerging disease in China. It affects not only the quality of rice but also yields of rice production. To make clear the effect of chemical seed treatment on the rice false smut control in fields, during 2014 to 2017, four fungicides with different modes of action were used to treat rice seeds contaminated by false smut balls. In rice-growing seasons, samples of rice tissues were taken for detection of U. virens by using a specific nested PCR method at different rice-growing stages. In addition, the occurrence of rice false smut was investigated at maturation stage. Results showed that U. virens in plant tissues decreased significantly at the seedling stage upon chemical seed treatment. Four chemical treatments decreased the detection rate significantly (P < 0.01) compared with the water treatment, but no significant difference was observed among four chemical treatments. However, the detection rate did not decease significantly at the tillering and booting stages. Similarly, the final occurrence of rice false smut did not show significant difference between each chemical and water treatment. These results suggested that chemical seed treatment had only limited efficacy in preventing occurrence of rice false smut; application of fungicides at the booting stage or integrated use of fungicides and agricultural practices might give a better control for this disease.

[Analysis of quality difference based on Astragalus membranaceus var. mongholicus in genuine region].

This work is to establish the fingerprint of Astragalus membranaceus var. mongholicus by HPLC-ELSD method, and to analyze the simulated wildness degree of A. membranaceus var. mongholicus in the genuine region of Inner Mongolia, Ningxia and Gansu. Compared with wild A. membranaceus var. mongholicus, the quality differences of A. membranaceus var. mongholicus in the genuine region were analyzed by identification of chromatographic peaks and similarity evaluation, cluster analysis(CA), principal components analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA). HPLC fingerprints of A. membranaceus var. mongholicus in different genuine regions are established. The qualitative analysis of mass spectrometry identified 18 components. The similarity evaluation shows that the similarity of 32 batches of A. membranaceus var. mongholicus samples was 0.688-0.993. Among them, the similarity of samples in Shanxi, Inner Mongolia, Ningxia is 0.688-0.993, 0.835-0.989, 0.934-0.988, respectively and the similarity of samples in Gansu is 0.729-0.876 except No. 25 sample. The results of CA show that the samples of A. membranaceus var. mongholicus can be grouped into four categories according to the production area except the No. 11 and No. 25 samples. The results of PCA indicate that 32 batches of A. membranaceus var. mongholicus samples can be clustered according to quality and origin, and the quality of A. membranaceus var. mongholicus in Inner Mongolia is the closest to the wild breed. The results of OPLS-DA indicate that there are six components that can distinguish the wild and domestic A. membranaceus var. mongholicus, which are malonylastragaloside Ⅰ, astragaloside Ⅰ, calycosin-7-O-ß-D-glycoside-6″-O-malonate, calycosin-7-O-ß-D-glycoside, formononetin-7-O-ß-D-glycoside-6″-O-malonate, and astrapterocarpan-3-O-ß-D-glycoside-6″-O-malonate. The established method can be used to analyze differences between A. membranaceus var. mongholicus origin and planting environment, and can provide references for the protection and replacement of wild A. membranaceus var. mongholicus resources, and the cultivation, processing and production of A. membranaceus var. mongholicus.

Methionine sulfone-containing orbitides, good indicators to evaluate oxidation process of flaxseed oil.

This study aimed to explore the possibility of using methionine sulfone (Msn)-containing orbitides as indicators to evaluate the oxidation process of flaxseed oils. Results showed that after 4 days' heating, oxidation values slightly increased (p > .05) with significant decrease in methionine (Met)-containing peptides (p < .05) instead of γ-tocopherol (p > .05). However, as oxidation time continues increasing, oxidation values significantly increased (p < .05) with significant reduction of γ-tocopherol (p < .05). It demonstrated that Met-containing peptides were more readily oxidized compared with γ-tocopherol and showed certain antioxidant activity. Besides, high logarithmic correlations were found between oxidation values and Msn-containing orbitides (0.94-1.00), such as between total carbonyl compounds and orbitide [1-8-NαC],[1-MetO2]-CLE (64.95 lnx - 52.14, R2 = 0.99, Dingya23 oil). Therefore, in comparison with common oxidation indices, Msn-containing orbitides may be better indicators for evaluating the oxidation process of flaxseed oil with superior separation efficiency, specific information and high stability.

Molecular electrostatic potential on the proton-donating atom as a theoretical descriptor of excited state acidity.

Organic photoacids with enhanced acidities in the excited states have received much attention both experimentally and theoretically because of their applications in nanotechnology and chemistry. In this study, we investigate the excited-state acidities of 14 hydroxyl-substituted aromatic photoacids, with a focus on using theoretical molecular electrostatic potential (MEP) as an effective descriptor for photoacidity. For these model photoacids, we applied time-dependent density functional theory (TDDFT) at the ωB97X-D/6-31G(d) level to calculate the molecular electrostatic potentials of S1 excited states and show that the molecular electrostatic potential on the proton-donating atom exhibits a linear relationship with the observed excited-state logarithmic acid dissociation constant (pKa*). As a result, the molecular electrostatic potential on the proton-donating atom can be used to estimate the pKa* values based on simple TDDFT calculations for a broad range of hydroxyl-substituted aromatic compounds. Furthermore, we explore the molecular electrostatic potential as a quantum descriptor for the photoacidities of cationic photoacids, and show a universal behavior of the pKa*-MEP dependence. We also investigate the solvent effects on the photoacidity using TDDFT calculations with implicit solvent models. Finally, we discuss the physical insights implicated by the molecular electrostatic potential as a successful measure for photoacidity on the mechanism of proton transfer in the molecular excited states. This pKa* descriptor provides an effective means to quantify the tendency of excited-state proton transfer with a relatively small computational cost, which is expected to be useful in the design of functional photoacids.

Osteoblast-oriented differentiation of BMSCs by co-culturing with composite scaffolds constructed using silicon-substituted calcium phosphate, autogenous fine particulate bone powder and alginate in vitro.

Autogenous bone graft is the best for spinal fusion in clinics, however, lacking sources, bleeding and infection are limited its practice. Seeking alternative materials are urgent for orthopaedic surgeon. Here, we evaluated osteoblast-oriented differentiation of rabbit BMSCs by co-culturing with composite scaffolds constructed using silicon-substituted-CaP-fine particulate bone powder-alginate. Using CCk8-kit, biocompatibility was evaluated by testing BMSCs proliferation; morphology and survival of osteoblasts within scaffolds were observed using EM and HE staining; growth factors and related genes were detected using RT-PCR. HE staining showed spindle-shaped BMSCs after the 3rd passage; EM data showed that uneven surface and longitudinal section were observed with scattered distribution of 5-100 mm interspaces, which leave enough space for BMSCs adhesion and growth. Interestingly, at 14-day culture with HE staining, osteocytes within the scaffolds grew well with regular shape and integrate structure. RT-PCR results showed that expression levels of BMP2, TGF-b and COL-I, ALP, OPN were increased significantly and time-dependently. Collectively, all mentioned effects were more obvious in co-culture BMSCs with scaffolds than those with other components. Immunohistochemistry showed that positive OPN expression was detected at 7-day co-culturing BMSCs with scaffold, rather than other situations. These results suggest that composite scaffolds constructed with Si-CaP-fine particulate bone powder-alginate have a certain degree of biocompatibility and bioactivity to promote osteoblast-oriented BMSCs differentiation.

Enhancement of Energy Production of the Intervertebral Disc by the Implantation of Polyurethane Mass Transfer Devices.

Insufficient nutrient supply has been suggested to be one of the etiologies for intervertebral disc (IVD) degeneration. We are investigating nutrient transport into the IVD as a potential treatment strategy for disc degeneration. Most cellular activities in the IVD (e.g., cell proliferation and extracellular matrix production) are mainly driven by adenosine-5'-triphosphate (ATP) which is the main energy currency. The objective of this study was to investigate the effect of increased mass transfer on ATP production in the IVD by the implantation of polyurethane (PU) mass transfer devices. In this study, the porcine functional spine units were used and divided into intact, device and surgical groups. For the device and surgical groups, two puncture holes were created bilaterally at the dorsal side of the annulus fibrosus (AF) region and the PU mass transfer devices were only implanted into the holes in the device group. Surgical groups were observed for the effects of placing the holes through the AF only. After 7 days of culture, the surgical group exhibited a significant reduction in the compressive stiffness and disc height compared to the intact and device groups, whereas no significant differences were found in compressive stiffness, disc height and cell viability between the intact and device groups. ATP, lactate and the proteoglycan contents in the device group were significantly higher than the intact group. These results indicated that the implantation of the PU mass transfer device can promote the nutrient transport and enhance energy production without compromising mechanical and cellular functions in the disc. These results also suggested that compromise to the AF has a negative impact on the IVD and must be addressed when treatment strategies are considered. The results of this study will help guide the development of potential strategies for disc degeneration.

Therapeutic Strategies of Plant-derived Compounds for Diabetes Via Regulation of Monocyte Chemoattractant Protein-1.

BACKGROUND: Monocyte chemoattractant protein-1 (MCP-1) is a member of the CC chemokine family that plays a key role in the inflammatory process. It has been broadly studied in the aspect of its role in obesity and diabetes related diseases. MCP-1 causes the infiltration of macrophages into obese adipose tissue via binding to the CCR2 receptor and is involved in the development of insulin resistance. METHODS: We reviewed the available literature regarding the importance of plant metabolites that regulate MCP-1 activity and are used in the treatment of diabetic disorders. The characteristics of screened papers were described and the important findings were included in this review. RESULTS: This mini-review provides a summary of functions and therapeutic strategies of this chemokine, with a special focus on plant-derived compounds that possess a putative antidiabetic function via a mechanism of MCP-1 interaction. The highlights of this review include the roles of MCP-1 in development of diabetes, the evaluation of plant metabolites that specifically or non-specifically inhibit MCP-1 overproduction, and the molecular mechanisms of this activity. Among these metabolites, we particularly focused on phenolic acids and their derivatives, flavonoids, stilbenes, anthocyanins, capsaicin, alkaloids, plant sterols, terpenes, saponins, unsaturated fatty acids and plant-derived extracts. CONCLUSION: Regarding the increasing number of diabetic patients yearly, the recent progress in the putative therapies needs to be summarized. This article underlines the significance and involvement of the chemokine MCP-1 in the development of obesity, type 2 diabetes, and diabetic complications, with an emphasis on the role of plant metabolites in the regulation of this chemokine and thus the role in the prevention or therapy of diabetes. We suggest that MCP-1 might be a molecular marker of type 2 diabetes.

Systematic characterization of porosity and mass transport and mechanical properties of porous polyurethane scaffolds.

One of the key challenges in porous scaffold design is to create a porous structure with desired mechanical function and mass transport properties which support delivery of biofactors and development of function tissue substitute. In recent years, polyurethane (PU) has become one of the most popular biomaterials in various tissue engineering fields. However, there are no studies fully investigating the relations between porosity and both mass transport and mechanical properties of PU porous scaffolds. In this paper, we fabricated PU scaffolds by combining phase inversion and salt (sodium chloride) leaching methods. The tensile and compressive moduli were examined on PU scaffolds fabricated with different PU concentrations (25%, 20% and 15% w/v) and salt/PU weight ratios (9/1, 6/1, 3/1 and 0/1). The mass transport properties of PU scaffolds including hydraulic permeability and glucose diffusivity were also measured. Furthermore, the relationships between the porosity and mass transport and mechanical properties of porous PU scaffold were systemically investigated. The results demonstrated that porosity is a key parameter which governs both mass transport and mechanical properties of porous PU scaffolds. With similar pore sizes, the mass transport and mechanical properties of porous PU scaffold can be described as single functions of porosity regardless of initial PU concentration. The relationships between scaffold porosity and properties can be utilized to facilitate porous PU scaffold fabrication with specific mass transport and mechanical properties. The systematic approach established in this study can be applied to characterization of other biomaterials for scaffold design and fabrication.

Observation of the origin of d0 magnetism in ZnO nanostructures using X-ray-based microscopic and spectroscopic techniques.

Efforts have been made to elucidate the origin of d(0) magnetism in ZnO nanocactuses (NCs) and nanowires (NWs) using X-ray-based microscopic and spectroscopic techniques. The photoluminescence and O K-edge and Zn L3,2-edge X-ray-excited optical luminescence spectra showed that ZnO NCs contain more defects than NWs do and that in ZnO NCs, more defects are present at the O sites than at the Zn sites. Specifically, the results of O K-edge scanning transmission X-ray microscopy (STXM) and the corresponding X-ray-absorption near-edge structure (XANES) spectroscopy demonstrated that the impurity (non-stoichiometric) region in ZnO NCs contains a greater defect population than the thick region. The intensity of O K-edge STXM-XANES in the impurity region is more predominant in ZnO NCs than in NWs. The increase in the unoccupied (occupied) density of states at/above (at/below) the conduction-band minimum (valence-band maximum) or the Fermi level is related to the population of defects at the O sites, as revealed by comparing the ZnO NCs to the NWs. The results of O K-edge and Zn L3,2-edge X-ray magnetic circular dichroism demonstrated that the origin of magnetization is attributable to the O 2p orbitals rather than the Zn d orbitals. Further, the local density approximation (LDA) + U verified that vacancies in the form of dangling or unpaired 2p states (due to Zn vacancies) induced a significant local spin moment in the nearest-neighboring O atoms to the defect center, which was determined from the uneven local spin density by analyzing the partial density of states of O 2p in ZnO.

Curcumin promotes the spinal cord repair via inhibition of glial scar formation and inflammation.

Spinal cord injury (SCI) is a serious clinical situation without any effective therapy to date. Traumatic SCI triggers a complex pathological process including inflammatory response and glial scar formation. In this study, we demonstrated that curcumin, a natural product which functions as an anti-inflammatory agent, inhibited the activation of signal transducer and activator of transcription-3 and NF-kappa B in the injured spinal cord. Curcumin treatment greatly reduced the astrogliosis in SCI mice and significantly decreased the expression of IL-1ß and NO, as well as the number of Iba1(+) inflammatory cells at the lesion site. Notably, more residual axons and neurons were protected and significantly improved functional recovery was observed in the curcumin-treated mice, compared to the mice without curcumin treatment. These findings indicate that curcumin promotes spinal cord repair through inhibiting glial scar formation and inflammation and suggests the therapeutic potential of curcumin for SCI.

Multisite constrained model of trans-4-(N,N-dimethylamino)-4'-nitrostilbene for structural elucidation of radiative and nonradiative excited states.

A constrained model compound of trans-4-(N,N-dimethylamino)-4'-nitrostilbene (DNS), namely, compound DNS-B3 that is limited to torsions about the phenyl-nitro C-N bond and the central C═C bond, was prepared to investigate the structural nature of the radiative and nonradiative states of electronically excited DNS. The great similarities in solvent-dependent electronic spectra, fluorescence decay times, and quantum yields for fluorescence (Φf) and trans → cis photoisomerization (Φtc) between DNS and DNS-B3 indicate that the fluorescence is from a planar charge-transfer state and torsion of the nitro group is sufficient to account for the nonradiative decay of DNS. This conclusion is supported by TDDFT calculations on DNS-B3 in dichloromethane. The structure at the conical intersection for internal conversion is associated with not only a twisting but also a pyramidalization of the nitro group. The mechanism of the NO2 torsion is discussed in terms of the effects of solvent polarity, the substituents, and the volume demand. The differences and analogies of the NO2- vs amino-twisted intramolecular charge-transfer (TICT) state of trans-aminostilbenes are also discussed.

Analysis of 2,297 expressed sequence tags (ESTs) from a cDNA library of flax (Linum ustitatissimum L.) bark tissue.

Bast fibre crops are the second most important natural fibre crops following cotton. Of these, flax (Linum ustitatissimum L.) is the most widely planted in the world, with its fibre used for high quality linen textile. A cDNA library of flax bark tissues was constructed with the purpose of identifying genes involved in the Bast fibre development. A total of 2,297 unigene sequences were obtained from 3,200 randomly selected clones of the cDNA library. These sequences were grouped into 155 clusters and 2,142 singletons, which have been submitted to the GenBank databases. By putative functional annotation, 23.3% of these sequences were similar to known proteins in GenBank, 44.0% of these sequences were similar to unknown proteins, and 32.7% of these sequences showed no significant similarity to any other protein sequences in existing databases. Classified by the Gene Ontology, 24.8, 23.1 and 14.3% were assigned to molecular function, biological process, and cellular component GO terms, respectively. By further bioinformatics approaches, about 110 ESTs matched cell wall related genes in the MAIZEWALL database, representing 16 functional categories of all 19 categories, of which, the most abundant category was protein synthesis. Based on the PlantTFDB database, 39 of the 64 transcription factor families in the Arabidopsis thaliana genome were identified as being involved in flax cell wall formation. The sequences and bioinformatics analysis data generated in this paper will be useful for gene expression, cloning and genetic engineering studies to characterize bast fibre development and improve the properties of the bast fibres.

A cell-penetrating peptide suppresses inflammation by inhibiting NF-κB signaling.

Nuclear factor-κB (NF-κB) is a central regulator of immune response and a potential target for developing anti-inflammatory agents. Mechanistic studies suggest that compounds that directly inhibit NF-κB DNA binding may block inflammation and the associated tissue damage. Thus, we attempted to discover peptides that could interfere with NF-κB signaling based on a highly conserved DNA-binding domain found in all NF-κB members. One such small peptide, designated as anti-inflammatory peptide-6 (AIP6), was characterized in the current study. AIP6 directly interacted with p65 and displayed an intrinsic cell-penetrating property. This peptide demonstrated significant anti-inflammatory effects in vitro and in vivo. In vitro, AIP6 inhibited the DNA-binding and transcriptional activities of the p65 NF-κB subunit as well as the production of inflammatory mediators in macrophages upon stimulation. Local administration of AIP6 significantly inhibited inflammation induced by zymosan in mice. Collectively, our results suggest that AIP6 is a promising lead peptide for the development of specific NF-κB inhibitors as potential anti-inflammatory agents.

[Study on the coinfection status of Borrelia burgdorferi sensu lato and spotted fever group Rickettsia in ticks from Hunchun, Jilin province].

OBJECTIVE: To understand the coinfection status of Borrelia burgdorferi sensu lato (B.b.s.l) and spotted fever group Rickettsia (SFGR) in Hunchun of Jilin province, China. METHODS: Polymerase chain reaction (PCR) was used to detect the 5S-23S rRNA intergenic spacer of B. b. s. l and ompA of SFGR in ticks was collected in Hunchun,Jilin province. The amplification products of positive ticks were sequenced, and phylogenetic analysis was conducted by PHYLIP software package. RESULTS: The infection rate of B. b. s. l was 36.0% in Ixodes persulcatus ticks and the SFGR was discovered in I. persulcatus ticks,with an infection rate of 2.0%. The coinfection rate of both agents was 2.0%. In 327 Dermacentor siltarum ticks, the positive rates of B. b. s. l and SFGR were 30.9% and 29.1% respectively. 55 ticks (16.8%) were coinfected with the two pathogens. The sequence analysis of B. b. s. l showed that the B. b. s. l in Jilin area, which were highly homologous, all belonged to B. garinii genotypes. The sequence analysis of SFGR positive products showed that the DNA secquence of the newly detected agent (JL-95) was close to the two previously described rickettsiae which were detected in I. ricinus from Slovakia (called IRS3 and IRS4). Phylogenetic relationships inferred from the comparison of these sequences with those of other genus Rickettsiae indicated that JL-95, IRS3 and IRS4 constituted a new rickettsial genotype and formed a separate cluster among the spotted fever group Rickettsiae. CONCLUSION: Coinfection of B. b. s. l and SFGR existed in Hunchun, Jilin province. The sequencing of specific fragment confirmed a new SFGR which was different from other rickettsiae known in China.