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The electrochemical N 2 fixation, which is far from practical application in aqueous solution under ambient conditions, is extremely challenging and requires a rational design of electrocatalytic centers. We observed that bismuth (Bi) might be a promising candidate for this task because of its weak binding with H adatoms, which increases the selectivity and production rate. Furthermore, we successfully synthesized defect-rich Bi nanoplates as an efficient noble-metal-free N 2 reduction electrocatalyst via a low-temperature plasma bombardment approach. When exclusively using 1 H NMR measurements with N 2 gas as a quantitative testing method, the defect-rich Bi(110) nanoplates achieved a 15 NH 3 production rate of 5.453 μg mg Bi -1  h -1 and a Faradaic efficiency of 11.68 % at -0.6 V vs. RHE in aqueous solution at ambient conditions., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Key Message: An EMS-induced single-base mutation at a splice site caused abnormal RNA splicing and resulted in the gene inactivation and the lack of Wx-A1 protein in a wheat EMS mutant line. An EMS-mutagenized population was generated using common wheat cv. SM126 consisting of 10,600 M2 plants. One Wx-A1 null mutant was identified through analyses of 390 grains produced from 130 M2 plants using electrophoresis analyses. The Wx-A1 sequences of parental line SM126 and M2-31 mutant were determined as 2781 bp, and there was only one SNP mutation between them. The SNP was a mutation from G to A at nucleotide sequence position 2168 bp (G2168A) downstream of the start codon which was located at the splicing site within the eighth intron. All 52 cDNA transcripts were found to be incorrectly spliced and can be summarized as five types of variations. The deletion of the exon and the exclusion of intron were structural features in abnormal splicing RNA. Together with the prediction of potential splice regulatory motifs, the mutation G2168A happened within the 5' splice site of the eighth intron and destroyed the splice donor site from GU to AU, which may have brought about a barrier against correct RNA splice, and generated abnormal mRNA, which was the mechanism of the inactivation of Wx-A1 in M2-31. The lack of Wx-A1 has resulted in changes in starch properties in the M2-31 mutant, with the reduction in amylose and starch contents. The increased grains hardness was observed in M2-31, which may be related to the lower expression level of Pinb-D1 gene. As the waxy wheat foods have a lot of advantages, the null waxy genes will be widely applied in breeding waxy wheat for varied amylose contents.

The knowledge of understanding the molecular traits of the sterile triploid fish is sparse. Herein, we analyzed the microRNA (miRNA) alternations in the testes of the sterile triploid fish produced by crossing the tetraploid fish with the diploid fish, compared with those of tetraploids and diploids used as the controls. A total of 136, 134, and 142 conserved miRNAs and 105, 112, and 119 novel miRNAs were identified in the diploid, triploid, and tetraploid fish, respectively. The genes targeted by the differentially expressed miRNAs were identified and were enriched in the GO term cell surface receptor signaling pathway, cellular process, G-protein coupled receptor signaling pathway, and metabolic process. KEGG pathway enrichment was also assessed to evaluate the target genes with differentially expressed miRNAs and these genes were enriched in four pathways (synthesis and degradation of ketone bodies, pentose and glucuronate interconversions, cyanoamino acid metabolic process, and ascorbate and aldarate metabolism). Nine differentially expressed miRNAs were verified by quantitative real-time PCR analysis (qPCR). The upregulated miRNAs in triploids, including miR-101a, miR-199-5p, miR-214, miR-222, and miR-193a, showed the same results with high-throughput sequencing. Among the selected downregulated miRNAs, miR-7b and miR-153b had significantly lower expression levels in triploids. Dnah3 and Tekt1 genes targeted by miR-199-5p showed lower expression in triploids by qPCR. These verified differentially expressed miRNAs may participate in testicular development and sperm activity by targeting functional genes, which were identified with differential expression in the triploid. This evidence provides insights into the epigenetic regulatory mechanisms of sterility in triploid cyprinids.

Purpose: On account of the potential inhibition of OATP1B1 (organic anion transporting polypeptide) by angiotensin II receptor blockers (ARBs) and the effects of SLCO1B1 (solute carrier organic anion transporter family member) polymorphism, the aim of current study is to assess the impact of ARBs on the pharmacokinetics (PK) and pharmacodynamics (PD) of repaglinide in Chinese healthy volunteers with different SLCO1B1 genotypes., Methods: The in vitro study was conducted on irbesartan, valsartan, olmesartan, and losartan by using HEK293 cells transfected with OATP1B1. Data on drug interactions between repaglinide and irbesartan from 21 healthy Chinese-Han male volunteers were collected and analyzed., Results: IC 50 from in vitro study suggested irbesartan was the most potent inhibitor of OATP1B1 transporter. Clinical data from single dose of repaglinide indicated SLCO1B1 c.521 T>C polymorphism influenced the PK and PD of repaglinide in healthy Chinese-Han male volunteers. In subjects with SLCO1B1 c.521 TT genotype, irbesartan comedication increased the exposure of repaglinide. In details, the peak plasma concentration [C max ] increased 84% (P = 0.003) and the area under the curve of plasma concentration 0-8 h [AUC 0-8 ] increased 34% (P = 0.004), while the minimum blood glucose concentration [C min ] decreased 33.8% (P = 0.005). No significant change was observed in repaglinide exposure in subjects with SLCO1B1 c.521 TC genotype in presence or absence of irbesartan., Conclusion: SLCO1B1 c.521 T>C polymorphism affects the PK of repaglinide in Chinese population. Irbesartan increased repaglinide exposure in subjects with SLCO1B1 c.521 TT genotype, but not SLCO1B1 c.521 TC genotype.

Distant hybridization refers to crosses between two different species, genera, or higher-ranking taxa, which can break species limits, increase genetic variation, and combine the biological characteristics of existing species. It is an important way of creating genetic variation, fertile strains, and excellent characteristics in new strains and populations. Combining analyses and summaries from many inter-related documents in plants and animals, both domestic and international, including examples and long-standing research on distant hybridization in fish from our laboratory, we summarize and compare the similarities and differences in plant and animal distant hybridization. In addition, we analyze and review the biological characteristics of their different ploidy progenies and the possible causes of disparity in survival rates. Mechanisms of sterility in animal and plant distant hybrids are also discussed, and research methods for the study of biological characteristics of hybrids, including morphology, cytology, and molecular cytogenetics are presented. This paper aims to provide comprehensive research materials and to systematically compare the general and specific characteristics of plant and animal hybrids with regards to reproduction, genetics, growth traits, and other biological characteristics. It is hoped that this paper will have great theoretical and practical significance for the study of genetic breeding and biological evolution of plant and animal distant hybridization.

Key Message: A novel Wx-B1 allele was characterized; a transposon insertion resulted in the loss of its function, which is different from the previously reported gene silencing mechanisms at the Wx-B1 locus. The waxy protein composition of 53 Chinese wheat landraces was analyzed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and two-dimensional gel electrophoresis; of these, 10 did not show the expression of Wx-A1 (four accession) or Wx-B1 (six accessions) protein. The results of molecular marker detection revealed that the Wx-B1 allele (Wx-B1n) showed normal expression, inconsistent with the findings of SDS-PAGE for the Xiaobaipi accession. Further cloning of the 9160-bp region covering the Wx-B1 coding region and 3'-downstream region revealed that a 2178-bp transposon fragment had been inserted at 2462 bp within the tenth exon of Wx-B1n ORF, leading to the absence of Wx-B1 protein. Sequence analysis indicated that the insertion possessed the structural features of invert repeat and target repeat elements, we deduced that it was a transposon. Further PCR analysis revealed that this fragment had moved, but not copied itself, from 3B chromosome to the current location in Wx-B1n. Therefore, the reason for the inactivation of Wx-B1n was considerably different from those for the inactivation of Wx-B1b, Wx-B1k, and Wx-B1m; to our knowledge, this kind of structural mutation has never been reported in Wx-B1 alleles. This novel allele is interesting, because it was not associated with the deletion of other quality-related genes included in the 67 kb region lost with the common null allele Wx-B1b. The null Wx-B1n might be useful for investigating gene inactivation and expression as well as for enriching the genetic resource pool for the modification of the amylose/amylopectin ratio, thereby improving wheat quality.

A novel virus-imprinted polymer for prevention of viral infection was prepared by anchoring molecularly imprinted polymer (MIP) on the surface of poly-dopamine (PDA)-coated silica particles. The imprinting reaction was carried out via self-polymerization of dopamine in the presence of a virus template. Plaque forming assay indicated that the MIP exhibited selective anti-viral infection properties for the template virus in complex media containing different interfering substances, and even other types of viruses. Remarkable dose-dependent and time-dependent inhibition of virus infection was observed due to the MIP's selective binding to the template virus. When the MIP was incubated with the virus and host cells together, rapid and selective adsorption of template viruses by the MIP prevented the viruses to infect the host cells in a period of 12h. The MIP was biocompatible and non-toxic, and had excellent stability and reusability. Furthermore, the MIPs prepared using different viruses as templates showed similar anti-viral infection properties. The MIP synthesized using dopamine as monomer and crude virus as template provided an attractive possibility for clinical applications in the field of antiviral therapy., Statement of Significance: This is the first report to prepare artificial antibody (molecularly imprinted polymer, MIP) that can selectively prevent virus infection using dopamine self-polymerization system. Only MIP anchoring on the surface of poly-dopamine coated silica particles and polymerized using ammonium persulfate as radical initiator showed dose-dependent and time-dependent inhibition of template virus infection in complex media containing interferences and even other viruses. Viruses bond to MIP lost infectious capability. When incubated with virus and host cells, MIP rebond viruses rapidly and selectively to prevent viruses infecting host cells for 12h. The achieved MIPs were biocompatibility, non-toxicity with excellent stability and reusability, and can be used to different viruses. The bio-mimic MIPs provided an attractive prospect for clinical applications in antiviral therapy., (Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Objective: To identify the genotypes of Toxoplasma gondii that infects HIV-positive people in Dali of Yunnan Province through analyzing the genetic loci of the surface antigens SAG1 and SAG3., Methods: A total of 291 blood samples from HIV-positive cases were collected from the HIV/AIDS Prevention and Control Institution in Yunnan. Nested PCR was used to amplify SAGI and SAG3 genes in the blood samples. The products were digested with restriction enzymes Sau96 I, Hae II and Nci I, and sequenced., Results: Of the 291 HIV-positive blood samples, 64 showed successful amplification of SAGI gene, and 42 of SAG3 gene, with product sizes of 390 bp and 225 bp, respectively. Enzymetic digestion of the PCR products resulted in fragments of 350 bp and 50 bp for SAGI, and -200 bp band for SAG3, consistent with RH, a particular type I strain of T. gondii. Sequencing of the SAG1 and SAG3 PCR products showed that their sequence identities with SAGI (Accession No. GQ253073) and SAG3 (Accession No. JX218225.1) of the type I strain of T. gondii were 99.98%-100% and 99.96% -99.98% respectively., Conclusion: The Toxoplasma gondii in HIV-positive cases in Dali of Yunnan Province is the type I strain of T. gondii.

Objective: To preliminarily understand the genotype characteristics of Toxoplasma gondii in blood of HIV-positive persons in Lincang City, Yunnan Province., Method: Two segments of SAG2 gene of T. gondii from blood samples of HIV-positive persons in Lincang City were extracted and amplified by using the nested PCR method and the genotype was identified and compared with the standard strain (Type I) of Toxoplasma gondii., Results: Thirty-five SAG2 genes (241 bp) and 35 SAG2 genes (221 bp) of T. gondii were amplified from 170 blood samples of the HIV-positive people, and 4 of each case were selected and digested with enzyme, then 2 aim gene fragments of each case were chosen and compared with the standard strain (Type I) of T. gondii. The digestion of SAG2 gene (241 bp) showed the genotype of the blood samples was Type I or Type II, and the digestion of SAG2 gene (221 bp) confirmed that the genotype was Type I., Conclusion: It is preliminarily confirmed that the genotype of T. gondii in blood of HIV-positive persons in Lincang City, Yunnan Province is Type I.

Toxoplasma gondii is an intracellular protozoan parasite that infects all warm-blooded animals. The surface antigens of T. gondii with the potential for application as antigens of diagnosis and vaccines have been studied extensively in recent years, especially for P43, P35, P30, P23 and P22. The studies on the surface antigen in tachyzoites of T. gondii are reviewed in this paper.

Objective: To comparatively analyze Toxoplasma gondii separated from HIV-positive people and RH strain GRA6 gene., Methods: By using the nested PCR, the amplification of Dali HIV-positive blood samples and RH strains of Toxoplasma GRA6 genome was performed. The GRA6 gene amplification positive product was selected and the electrophoresis imaging was performed by being digested with the Mse I endonuclease, and the gene sequences were measured and analyzed., Results: The GRA6 gene fragment (800 bp) was successfully amplified, and about 600 bp and 200 bp bands were got by Mse I. The sequencing results showed that T. gondii GRA6 gene positive samples had 2 nucleotide variation compared with T. gondii strain RH, namely 447 base pair at C becoming G, and 623 base pair at G becoming T. At 146 bp and 690 bp, the Mse I restriction sites (TTAA) were found., Conclusion: The preliminary judgment shows that the Dali HIV-positive T. gondii genotype is consistent with RH strain, belonging to genotype I.

Tolvaptan is a selective vasopressin V(2)-receptor antagonist mainly used for the treatment of hyponatremia. This study described the development and validation of an LC-MS/MS method for the determination of tolvaptan in human plasma. Sample preparation involved protein precipitation with acetonitrile containing 2-demethyl tolvaptan (internal standard, IS). Chromatographic separation was performed on a Zorbax XDB C(18) column with an isocratic mobile phase consisting of water (containing 0.1% formic acid) and methanol (25:75, v/v). Determination of the analytes was achieved by tandem-mass spectrometry with positive electrospray ionization. The multiple reaction monitoring (MRM) transitions were performed at m/z 449.2→252.1 for tolvaptan and m/z 435.2→238.1 for IS. The assay was linear over the concentration range of 0.457-1000ng/mL, with a lower limit of quantification of 0.457ng/mL. The intra- and inter-day precisions at three concentration levels (0.914, 111 and 800ng/mL) were less than 15% and their accuracies were within the range of 97.7-107.8%. The mean recovery ranged from 99.2 to 104.6% and the matrix effect from 89.3 to 99.5%. Tolvaptan was stable under all tested conditions. This validated method was successfully applied to a pharmacokinetic study in healthy volunteers after oral administration of single-dose tolvaptan tablets., (Copyright © 2012 Elsevier B.V. All rights reserved.)