[Objective] The aim was to provide basic reference for the use of H-FABP gene in marker-assisted selection of the breeding process of pig.[Method] Single-nucleotide polymorphisms of the H-FABP gene in Shanxi White pig...[Objective] The aim was to provide basic reference for the use of H-FABP gene in marker-assisted selection of the breeding process of pig.[Method] Single-nucleotide polymorphisms of the H-FABP gene in Shanxi White pig,Mashen pig,Large White pig,Landrace and Duroc were tested by PCR-SSCP,and the correlation between genotype and intramuscular fat content in pigs were analyzed.[Result] One polymorphism was found in the amplified region of intron 1 of porcine H-FABP gene,in which two alleles(A and B)and three genotypes(AA,AB,and BB)were examined.C→T transition was detected by sequencing the homozygotes.The multiple comparison of the distribution of genotype in different pig varieties revealed that Mashen pig showed extremely significant difference(P0.01)in genotype distribution with Shanxi White,Landrace,Large White and Duroc breeds;whereas no significant differences(P0.05)were found in genotype distribution between other breeds.Based on the fixed effect model,extremely significant differences(P 0.01)were found in the intramuscular fat content among different H-FABP genotypes.Using least square analysis,it was found that there was significant differences(P 0.05)in the intramuscular fat content between the individuals of the BB genotypes and those of the AA genotypes.[Conclusion] The H-FABP genotype had significant effects on the meat quality.展开更多
[ Objective] The aim of this study was to provide a theoretical basis for exploring the major genes affecting intramuscular fat (IMF) deposition. [Method] Taking 383 pigs from five breeds including Mashen Pig, Large...[ Objective] The aim of this study was to provide a theoretical basis for exploring the major genes affecting intramuscular fat (IMF) deposition. [Method] Taking 383 pigs from five breeds including Mashen Pig, Large White Pig, Landrace, Duroc and Shanxi White Pig as the experimental animals, polymorphisms of partial fragments in the third intron of porcine H-FABP gene were detected by PCR-SSCP method, and then the polymorphic fragments were sequenced. [ Result] Two alleles, designated as A and B, were found at the locus 346 in the third intron of porcine H-FABP gene, and the mutation was caused by a A→G substitution. [ Conclusion] A polymorphic locus was discovered in the third intron of porcine H-FABP gene in this experiment, laying a foundation for the further study on the relationship between H-FABP gene and IMF content.展开更多
Reverse_transcription Polymerase Chain Reaction (RT_PCR) was performed using cDNAs as templates from wheat_ Haynaldia villosa 6VS/6AL translocation line and 'Yangmai 5' induced with fungus Erysiphe gramin...Reverse_transcription Polymerase Chain Reaction (RT_PCR) was performed using cDNAs as templates from wheat_ Haynaldia villosa 6VS/6AL translocation line and 'Yangmai 5' induced with fungus Erysiphe graminis , and degenerate primers designed based on the conserved amino acid sequences of known plant disease_resistance genes. The cDNA sequences encoding cyclophilin_like and H +_ATPase_like genes were first isolated and characterized in wheat. The putative amino acid sequences of the two clones showed that they were highly homologous to those of cyclophilin proteins and H +_ATPases isolated from other plants. Thus they were designated as Ta_Cyp and Ta_MAH . The obvious expression differences could be observed between wheat_ H. villosa 6VS/6AL translocation line and susceptible wheat cultivar 'Yangmai 5', implying that the two genes may be related with the resistance of wheat_ H. villosa 6VS/6AL translocation line to disease. Southern blot indicated that the wheat genome contained 2-3 copies of Ta_Cyp gene and one copy of the Ta_MAH gene. Chinese Spring nulli_tetrasomic line analysis located the Ta_Cyp homologous genes on wheat chromosome 6A, 6B and 6D. Southern blot using Ta_Cyp clone as a probe showed that the polymorphic bands existed among the H. villosa , amphiploid of Triticum durum _ H. villosa , wheat_ H. villosa 6VS/6AL translocation line and 'Yangmai 5', suggesting that Ta_Cyp homologies exist in wheat genome as well as on the short arm of chromosome 6V in H. villosa .展开更多
[ Objective] This study was to investigate the distribution of H-FABP mRNA in hybrids of Songliao black pig x Sus scrofa, so as to provide references for revealing the physiological functions of this gene. [Method] Wi...[ Objective] This study was to investigate the distribution of H-FABP mRNA in hybrids of Songliao black pig x Sus scrofa, so as to provide references for revealing the physiological functions of this gene. [Method] With the mRNA from different tissues as template, RT-PCR amplification was carried out for cloning cDNA of hybrid pig, which was then used for PCR reaction using specific primers; the amplification products were separated by gel electrophoresis and analyzed by sequencing for detecting the distribution pattern of H-FABP mRNA in hybrids of Songliao black pig x Sus scrofa. [ Result] H-FABP expressed in all the twelve tissues including subcutaneous fat, abdominal fat, mammary gland, Iongissimus dorsi muscle, dorsal deltoid muscle, heart, liver, spleen, lung, kidney, ileum and duodenum. [ Conclusion] The wide distribution of H-FABP gene suggests that its functions are important and multiple.展开更多
Prediction of vapor-liquid equilibrium (VLE) is extremely necessary to separate liquid mixture in chemical production, especially when the required experimental data are difficult to measure, or the measurement is n...Prediction of vapor-liquid equilibrium (VLE) is extremely necessary to separate liquid mixture in chemical production, especially when the required experimental data are difficult to measure, or the measurement is not economical. The infinite dilution activities can be used to predict VLE. However, it needs both the ends of the activities that are difficult to obtain for many systems. In the present study, a new model is proposed for correlating the frequency shift of C-H stretching band of IR spectra over the whole concentration. Investigated mixtures in- clude water/2-propanol, water/N, N-dimethylformamide (DMF), water/methanol, water/ethanol, water/1, 4-dioxane, and water/dimethylsulfoxide (DMSO) systems. Simultaneous correlations of C--H frequency shift and VLE data are made. Furthermore, the VLE data were predicted with satisfactory results by the parameters obtained from IR spectra coupled with one ot the intinite chlution activity coefficients.展开更多
With the aim of achieving a high 5-hydroxymethylfurfural(HMF)yield from glucose with H-ZSM-5 catalyst at low cost,three inexpensive biphasic reaction systems,H2O?tetrahydrofuran(THF),H2O?2-methyltetrahydrofuran(MeTHF)...With the aim of achieving a high 5-hydroxymethylfurfural(HMF)yield from glucose with H-ZSM-5 catalyst at low cost,three inexpensive biphasic reaction systems,H2O?tetrahydrofuran(THF),H2O?2-methyltetrahydrofuran(MeTHF)and H2O?2-butanol,were discovered and proved to be particularly effective in promoting the formation of HMF from glucose over H-ZSM-5 zeolite.In order to determine the optimal process conditions,the effects of various experimental variables,such as reaction temperature,reaction time,catalyst dosage,volume of organic solvent,as well as inorganic salt type on glucose conversion to HMF in three systems were investigated in detail.It was found that under optimal reaction conditions,H2O?THF,H2O?2-butanol and H2O?MeTHF allowed the glucose dehydration process to achieve HMF yields of up to 61%,59%,and 50%,respectively.Moreover,in the three biphasic systems,the H-ZSM-5 catalyst was also demonstrated to maintain excellent stability.Thus,the catalytic approach proposed in this paper can be believed to have potential prospects for industrially efficient and low-cost production of HMF.展开更多
Syrian hamster ernbryo(SHE) cells are irradiated by a particles emitted from Plutonium-238 in vtiro.Transfection frequencies of donor DNA derived from passaged cells,including monocloned cells from 20th passage cells,...Syrian hamster ernbryo(SHE) cells are irradiated by a particles emitted from Plutonium-238 in vtiro.Transfection frequencies of donor DNA derived from passaged cells,including monocloned cells from 20th passage cells,after irradiation are parallel with their tumorigenicity of donor cells. After trans formation, expressions of H-ras and c-myc genes are in the state of activation, which might be resulted from occurrence of mutation in H-ras gene and hypomethylation of c-myc gene respectively, even though no alteration was observed on their restriction fragment length polymorphisms(RELP) patterns of both genes. On the other hand,expression of p53 gene is also found to be in the state of activation in transformant, but no heavy staining of p53 protein appeared in the transformant-derived tumor with p53 specific McAb HD 200. This might be result from the partlal deletion of p53 cDNA in transformant by reverse transcriptional polymerase chain reaction(RT PCR). These results imply that activation of H-ras and c-myc genes coupled with inactivation of p53 turnor suppressor gene play important role in a particle-induced cell trans formation.展开更多
Hexagonal boron nitride(h-BN)is a highly selective catalyst for oxidative dehydrogenation of light alkanes to produce the corresponding alkenes.Despite intense recent research effort,many aspects of the reaction mecha...Hexagonal boron nitride(h-BN)is a highly selective catalyst for oxidative dehydrogenation of light alkanes to produce the corresponding alkenes.Despite intense recent research effort,many aspects of the reaction mechanism,such as the observed supra-linear reaction order of alkanes,remain unresolved.In this work,we show that the introduction of a low concentration of propane in the feed of ethane oxidative dehydrogenation is able to enhance the C_(2)H_(6) conversion by 47%,indicating a shared reaction intermediate in the activation of ethane and propane.The higher activity of propane makes it the dominant radical generator in the oxidative co-dehydrogenation of ethane and propane(ODEP).This unique feature of the ODEP renders propane an effective probe molecule to deconvolute the two roles of alkanes in the dehydrogenation chemistry,i.e.,radical generator and substrate.Kinetic studies indicate that both the radical generation and the dehydrogenation pathways exhibit a first order kinetics toward the alkane partial pressure,leading to the observed second order kinetics of the overall oxidative dehydrogenation rate.With the steady-state approximation,a radical chain reaction mechanism capable of rationalizing observed reaction behaviors is proposed based on these insights.This work demonstrates the potential of ODEP as a strategy of both activating light alkanes in oxidative dehydrogenation on BN and mechanistic investigations.展开更多
[Objective] The aim was to construct a recombinant pseudorabies virus expressing canine distemper virus H gene and investigate its biological characters.[Method] H gene of canine distemper virus(CDV)strain Onderstep...[Objective] The aim was to construct a recombinant pseudorabies virus expressing canine distemper virus H gene and investigate its biological characters.[Method] H gene of canine distemper virus(CDV)strain Onderstepoort was produced by RT-PCR,inserted into pcDNA3.1(+)vector to construct a expression cassette,which was then subcloned into transfer vector p8AA,prior to the insertion of LacZ expression cassette.The resulting new transfer vector was named as p8AAZH.Subsequently,p8AAZH was co-transfected with the genome of pseudorabies virus(PRV)Bartha-K61 into BHK-21 cells to enable gene recombination and virus package,and the virus solution was collected as cytopathic effect occurring.A series of procedures including blue plaque purification,PCR identification,observation under electron microscope and Western blot were carried out to screen the recombinant pseudorabies virus and identify the protein expression of target gene.Meanwhile,growth curve of the recombinant virus was determined in BHK-21 cells.[Result] The H gene had been inserted into the genome of Bartha-K61 strain,and RPRV-H was the same as Bartha-K61 in the one-step growth curve and cytopathic effect in BHK-21 cells.[Conclusion] The recombinant pseudorabies virus was constructed,and the insertion of H gene did not influence proliferation of recombinant virus,which laid a foundation for development of recombinant canine distemper virus vaccine.展开更多
[Objective] This study was to develop a live vector vaccine of goat pox virus of Peste des petits ruminants(PPR). [Method] Using PCR amplification technique, PPR H gene was obtained, then ligated into pGEM-T easy vect...[Objective] This study was to develop a live vector vaccine of goat pox virus of Peste des petits ruminants(PPR). [Method] Using PCR amplification technique, PPR H gene was obtained, then ligated into pGEM-T easy vector; the recombinants were digested by Nhe Ⅰ and Hind Ⅲ, and ligated into pEGFP-N1-P7.5, yielding the recombinant vector pEGFP-N1-P7.5-H; next the expression cassette EGFP-N1-P7.5-H was first released from recombinant vector pEGFP-N1-P7.5-H by double digestion of Hind Ⅲ and Nhe Ⅰ and ligated into pUC119-TK that was digested by Kpn Ⅰ, yielding the transfer vector pUC119-TK-EGFP-P7.5-H. [Result] Identification and double enzyme digestion showed that the transfer vector pUC119-TK-EGFP-P7.5-H was correctly constructed. From the transfer vector transfected BHK-21 cells which infected GTPV AV41, specific fluorescence was observed at 48th h of transfection. [Conclusion] The construction of goat poxvirus live vector laid a foundation for the live vector vaccine of PPR vaccine.展开更多
The Na+/H+ antiport genes namedTaNHX1andTaNHX2were cloned by screening a salt_stressed wheat cDNA library using rice Na+/H+ antiport cDNA fragment as the probe. Sequencing analysis showed thatTaNHX1was 2 029 bp in le...The Na+/H+ antiport genes namedTaNHX1andTaNHX2were cloned by screening a salt_stressed wheat cDNA library using rice Na+/H+ antiport cDNA fragment as the probe. Sequencing analysis showed thatTaNHX1was 2 029 bp in length and contained a complete ORF of 1 638 bp. TheTaNHX1encodes a polypeptide of 546 amino acids with a transmembrane domain DIFFIYLLPPI.TaNHX2was 1 693 bp in length consisting of a partial ORF followed by a 3′_UTR of 808 bp. The amino acid sequence of these two genes were about 70% identical to the known NHX genes from rice, Arabidopsis and Atriplex. A RT_PCR assay showed that the level ofTaNHX1transcripts was increased and reached a steady higher level in the seedlings after 3 h treatment with 400 mmol/L NaCl.展开更多
[Objective] This study aimed to screen an Na+/H+ antiporter gene from the halophiles colonizing in the Dagong Ancient Brine Well in Zigong City, China, and then analyze the gene structure and properties of the prote...[Objective] This study aimed to screen an Na+/H+ antiporter gene from the halophiles colonizing in the Dagong Ancient Brine Well in Zigong City, China, and then analyze the gene structure and properties of the protein encoded by this gene. [Method] Metagenomic DNA libraries of halophiles from the Dagong Ancient Brine Well were used for screening genes with Na+/H+ antiporter activity in antiporter-defi- cient E. coil KNabc strain by functional complementation. Then the start codon, stop codon, ORF, -35 region, -10 region and SD sequence of Na~/H+ antiporter gene, as well as the molecular weight, isoelectric point, hydrophobic region, transmembrane domain, phyletic evolution and salt resistance of protein encoded by the gene were investigated. [Result] A new Na+/H+ antiporter gene m-nha was obtained, which ,ren- dered the antiporter-negative mutant E. coil KNabc cells with both the resistance to Na+ and the ability to grow under alkaline conditions. [Conclusion] The structure and amino acid sequence of M-Nha was different from the previously reported Na+/H~ antiporters, and the m-nha gene disclosed from the Dagong Ancient Brine Well was identified as a novel Na+/H+ antiporter gene. This study was significant not only in helping us understand the salt tolerance of halophiles in ancient brine wells and develop and utilize the genes resource, but also in exploring new salt-tolerant genes.展开更多
AIM:To investigate the differences in cultivable gut bacteria and peroxisome proliferator-activated receptor γ2(PPAR-γ2) gene Pro12Ala variation in obese and normal-weight Chinese people.METHODS:Using culture method...AIM:To investigate the differences in cultivable gut bacteria and peroxisome proliferator-activated receptor γ2(PPAR-γ2) gene Pro12Ala variation in obese and normal-weight Chinese people.METHODS:Using culture methods,the amounts of Escherichia coli,Enterococci,Bacteroides,Lactobacilli,Bif idobacteria and Clostridium perfringens(C.perfringens) in the feces of 52 obese participants [body mass index(BMI):≥ 28 kg/m2] and 52 participants of normalweight(BMI:18.5-24 kg/m2) were obtained.Study participants completed comprehensive questionnaires and underwent clinical laboratory tests.The polymerase chain reaction-restriction fragment length polymorphism(PCR-PFLP) assay was used to analyze PPAR-γ2 gene Pro12Ala variation.RESULTS:The obese group exhibited a lower amount of C.perfringens(6.54 ± 0.65 vs 6.94 ± 0.57,P = 0.001)and Bacteroides(9.81 ± 0.58 vs 10.06 ± 0.39,P = 0.012) than their normal-weight counterparts.No major differences were observed in Pro12Ala genotype distribution between the two groups;however,obese individuals with a Pro/Ala genotype had a signif icantly lower level of Bacteroides(9.45 ± 0.62 vs 9.93 ± 0.51,P = 0.027) than those with a Pro/Pro genotype.In addition,the obese group demonstrated a higher stool frequency(U = 975,P < 0.001) and a looser stool(U = 1062,P = 0.015) than the normal-weight group.CONCLUSION:Our results indicated interactions among cultivable gut flora,host genetic factors and obese phenotype and this might be helpful for obesity prevention.展开更多
Vibrio parahaemolyticus (VP) is one of the pathogenic vibrios endangering net-cage cultured Pseudosciaena crocea,Fennerpenaeus chinensis, and shellfish in coastal areas of China. Several types of hemolysins produced b...Vibrio parahaemolyticus (VP) is one of the pathogenic vibrios endangering net-cage cultured Pseudosciaena crocea,Fennerpenaeus chinensis, and shellfish in coastal areas of China. Several types of hemolysins produced by Vp have been characterized as major virulence factors.They are thermostable direct hemolysin (TDH),TDH-related hemolysin (TRH) and thermolabile hemolysin (TLH). In this study, we cloned tdh, trh, and tlh genes from the genome DNA of VP by polymerase chain reaction (PCR).We ligated the three genes into prokaryotic expression vector pET-28a (+),and transformed the recombinant plasmids into Es-cherichia coli BL21 (DE3). The expression of recombinant proteins was induced by isopropyl-β-D-thiogalacto-pyranoside (IPTG). The recombinant proteins were expressed in a form of inclusion bodies and thus purified with Ni-NTA affinity chromatography. Western blotting results showed that recombinant proteins,TDH, TRH and TLH, could be recognized by rabbit anti-VP serum. The three purified proteins were renatured by gradient dialysis.The renatured proteins exhibited hemolytic activity except for TLH in the presence of phosphatidylcholine. These results not only are helpful for better understanding these genes' functions under a single factor level, but also provide evidence for VP vaccine engineering.展开更多
[Objective] The aim was to investigate AtNHX1 gene transformation in Brassica napus L. mediated by Agrobacterium tumefaciens. [Method] By using Agrobacterium-mediated method and cre/lox plant expression vector,the tra...[Objective] The aim was to investigate AtNHX1 gene transformation in Brassica napus L. mediated by Agrobacterium tumefaciens. [Method] By using Agrobacterium-mediated method and cre/lox plant expression vector,the transformation of AtNHX1 gene of Na+/H+ antiporter in Brassica napus was studied. [Result] The regeneration rate of cotyledon with petiole was much higher than that of hypocotyl,thus,the cotyledon with petiole was selected as the recipient for transformation. After the cotyledon with petiole was soaked in bacterial solution (OD600=0.4) for 8-10 min,kanamycin-resistant green seeding percentage could reach 3.75%. [Conclusion] The PCR detection of kanamycin-resistant plants proved that NHX1 gene had been inserted into Brassica napus genome. And this research could provide a new way to improve the salt tolerance of Brassica napus.展开更多
The Meyerhof and Hanna′s(M-H) method to estimate the ultimate bearing capacity of layered foundations was improved. The experimental results of the load tests in Tianjin New Harbor were compared with predictions with...The Meyerhof and Hanna′s(M-H) method to estimate the ultimate bearing capacity of layered foundations was improved. The experimental results of the load tests in Tianjin New Harbor were compared with predictions with the method recommended by the code for the foundations of harbor engineering, i.e. Hansen′s method and the improved M-H method. The results of the comparisons implied that the code and the improved M-H method could give a better prediction.展开更多
Cyclin-dependent kinase 7 (Cdk7) is the catalytic subunit of the metazoan Cdk-activating kinase (CAK). Activation of Cdk7 requires its association with a regulatory subunit, Cyclin H. Although the Cdk7/Cyclin H co...Cyclin-dependent kinase 7 (Cdk7) is the catalytic subunit of the metazoan Cdk-activating kinase (CAK). Activation of Cdk7 requires its association with a regulatory subunit, Cyclin H. Although the Cdk7/Cyclin H complex has been implicated in the regulation ofRNA polymerase in several species, the precise function of their orthologs in zebrafish has not been fully elucidated. In this study, we isolated from zebrafish blastula embryos two cDNAs encoding the orthologs of human Cyclin H and Cdk7, and examined the role of Cdk7/Cyclin H in zebrafish embryogenesis. Sequence analysis showed that the zebrafish Cyclin H and Cdk7 cDNAs encode proteins with 65% and 86% identity to the respective hu- man orthologs. RT-PCR and whole-mount in situ hybridization analyses of their expression in unfertilized eggs, embryos and organs of adult fish suggested that Cyclin H and Cdk7 messages are maternally loaded. Our data also showed that their transcripts were detected throughout development. Distribution of Cyclin H transcripts was found to be ubiquitous during early stages of development and become restricted to the anterior neural tube, brain, eyes, procreate tissues, liver and heart by 5 days post-fertilization. Expression of a dominant-negative form of Cyclin H delayed the onset of zygotic transcription in the early embryo, resulting in apoptosis at 5 hours post-fertilization and leading to sever defects in tis- sues normally exhibiting high levels of Cyclin H expression. These results implicate Cyclin H in the regulation of the transcriptional machinery during midblastula transition and suggest that it is an essential gene in early zebrafish larval development.展开更多
The development of practical methods for the direct and selective C(sp^(3))‒H functionalization of hydrocarbons is an attractive topic in synthetic chemistry.Although the radical‐mediated hydrogen atom transfer(HAT)p...The development of practical methods for the direct and selective C(sp^(3))‒H functionalization of hydrocarbons is an attractive topic in synthetic chemistry.Although the radical‐mediated hydrogen atom transfer(HAT)process has shown considerable potential in such reactions,it still faces fundamental problems associated with reactivity and selectivity.Herein,we report a convenient and economic approach to site‐selective C(sp^(3))‒H sulfonylation via photo‐induced HAT catalysis.Employing a conjugated polycyclic quinone as a direct HAT photocatalyst,commercially available inorganic sulfinates as the sulfonylation source,copper triflate as an inexpensive oxidant,a variety of toluene derivatives and cycloalkanes were converted into biologically and synthetically interesting sulfone products under mild conditions.The mechanistic studies reveal that the reaction sequence involves direct HAT‐induced radical formation and a subsequent copper‐mediated organometallic process for the C‒S bond formation.This method offers an appealing opportunity to furnish high value‐added products from abundant hydrocarbon starting materials and inexpensive reagents.展开更多
Direct photocatalytic coupling of methanol to ethylene glycol(EG)is highly attractive.The reported photocatalysts for this reaction are all metal sulfide semiconductors,which may suffer from photocorrosion and have lo...Direct photocatalytic coupling of methanol to ethylene glycol(EG)is highly attractive.The reported photocatalysts for this reaction are all metal sulfide semiconductors,which may suffer from photocorrosion and have low stability.Thus,the development of non‐sulfide photocatalysts for efficient photocatalytic coupling of methanol to EG and H2 with high stability is urgent but extremely challenging.Herein,the first metal oxide photocatalyst,tantalum‐based semiconductor,is reported for preferential activation of C−H bond within methanol to form hydroxymethyl radical(•CH_(2)OH)and subsequent C−C coupling to EG.Compared with other metal oxide photocatalysts,such as TiO2,ZnO,WO_(3),Nb_(2)O_(5),tantalum oxide(Ta_(2)O_(5))is unique in that it can realize the selective photocatalytic coupling of methanol to EG.The co‐catalyst free nitrogen doped tantalum oxide(2%N‐Ta_(2)O_(5))shows an EG formation rate as high as 4.0 mmol gcat−1 h−1,about 9 times higher than that of Ta_(2)O_(5),with a selectivity higher than 70%.The high charge separation ability of nitrogen doped tantalum oxide plays a key role in its high activity for EG production.This catalyst also shows excellent stability longer than 160 h,which has not been achieved over the reported metal sulfide photocatalysts.Tantalum‐based photocatalyst is an environmentally friendly and highly stable candidate for photocatalytic coupling of methanol to EG.展开更多
The oxidative dehydrogenation(ODH) of propane on monomeric VO3 supported by CeO2(111)(VO3/CeO 2(111)) is studied by periodic density functional theory calculations. Detailed energetic, structural, and electron...The oxidative dehydrogenation(ODH) of propane on monomeric VO3 supported by CeO2(111)(VO3/CeO 2(111)) is studied by periodic density functional theory calculations. Detailed energetic, structural, and electronic properties of these reactions are determined. The calculated activation energies of the breaking of the first and second C–H bonds of propane on the VO3/CeO2(111) catalyst are compared, and it is found that both the unique structural and electronic effects of the VO3/CeO2(111) catalyst contribute to the relatively easy rupture of the first C–H bond of the propane molecule during the ODH reaction. In particular, the so-called new empty localized states that are mainly constituted of O2 porbitals of the ceria-supported VO3 species are determined to be crucial for assisting the cleavage of the first C–H bond of the propane molecule. Following this they become occupied and the remaining C–H bonds become increasingly difficult to break owing to the increasing repulsion between the localized 4 felectrons at the Cecations, resulting in the adsorption of more H and other moieties. This work illustrates that CeO2-supported monomeric vanadium oxides can exhibit unique activity and selectivity for the catalytic ODH of alkanes to alkenes.展开更多
基金Supported by Scientific Research Start Project of Hebei United University(07101168)~~
文摘[Objective] The aim was to provide basic reference for the use of H-FABP gene in marker-assisted selection of the breeding process of pig.[Method] Single-nucleotide polymorphisms of the H-FABP gene in Shanxi White pig,Mashen pig,Large White pig,Landrace and Duroc were tested by PCR-SSCP,and the correlation between genotype and intramuscular fat content in pigs were analyzed.[Result] One polymorphism was found in the amplified region of intron 1 of porcine H-FABP gene,in which two alleles(A and B)and three genotypes(AA,AB,and BB)were examined.C→T transition was detected by sequencing the homozygotes.The multiple comparison of the distribution of genotype in different pig varieties revealed that Mashen pig showed extremely significant difference(P0.01)in genotype distribution with Shanxi White,Landrace,Large White and Duroc breeds;whereas no significant differences(P0.05)were found in genotype distribution between other breeds.Based on the fixed effect model,extremely significant differences(P 0.01)were found in the intramuscular fat content among different H-FABP genotypes.Using least square analysis,it was found that there was significant differences(P 0.05)in the intramuscular fat content between the individuals of the BB genotypes and those of the AA genotypes.[Conclusion] The H-FABP genotype had significant effects on the meat quality.
基金Supported by Doctoral Start-up Fund for Scientific Research in North China Coal Medical University (07101168)~~
文摘[ Objective] The aim of this study was to provide a theoretical basis for exploring the major genes affecting intramuscular fat (IMF) deposition. [Method] Taking 383 pigs from five breeds including Mashen Pig, Large White Pig, Landrace, Duroc and Shanxi White Pig as the experimental animals, polymorphisms of partial fragments in the third intron of porcine H-FABP gene were detected by PCR-SSCP method, and then the polymorphic fragments were sequenced. [ Result] Two alleles, designated as A and B, were found at the locus 346 in the third intron of porcine H-FABP gene, and the mutation was caused by a A→G substitution. [ Conclusion] A polymorphic locus was discovered in the third intron of porcine H-FABP gene in this experiment, laying a foundation for the further study on the relationship between H-FABP gene and IMF content.
文摘Reverse_transcription Polymerase Chain Reaction (RT_PCR) was performed using cDNAs as templates from wheat_ Haynaldia villosa 6VS/6AL translocation line and 'Yangmai 5' induced with fungus Erysiphe graminis , and degenerate primers designed based on the conserved amino acid sequences of known plant disease_resistance genes. The cDNA sequences encoding cyclophilin_like and H +_ATPase_like genes were first isolated and characterized in wheat. The putative amino acid sequences of the two clones showed that they were highly homologous to those of cyclophilin proteins and H +_ATPases isolated from other plants. Thus they were designated as Ta_Cyp and Ta_MAH . The obvious expression differences could be observed between wheat_ H. villosa 6VS/6AL translocation line and susceptible wheat cultivar 'Yangmai 5', implying that the two genes may be related with the resistance of wheat_ H. villosa 6VS/6AL translocation line to disease. Southern blot indicated that the wheat genome contained 2-3 copies of Ta_Cyp gene and one copy of the Ta_MAH gene. Chinese Spring nulli_tetrasomic line analysis located the Ta_Cyp homologous genes on wheat chromosome 6A, 6B and 6D. Southern blot using Ta_Cyp clone as a probe showed that the polymorphic bands existed among the H. villosa , amphiploid of Triticum durum _ H. villosa , wheat_ H. villosa 6VS/6AL translocation line and 'Yangmai 5', suggesting that Ta_Cyp homologies exist in wheat genome as well as on the short arm of chromosome 6V in H. villosa .
基金Supported by the National High Technology Research and Develop-ment Program of China(No.2008AA10Z136)the Program of Liaoning Provincial Science-Technology Department(20070567)~~
文摘[ Objective] This study was to investigate the distribution of H-FABP mRNA in hybrids of Songliao black pig x Sus scrofa, so as to provide references for revealing the physiological functions of this gene. [Method] With the mRNA from different tissues as template, RT-PCR amplification was carried out for cloning cDNA of hybrid pig, which was then used for PCR reaction using specific primers; the amplification products were separated by gel electrophoresis and analyzed by sequencing for detecting the distribution pattern of H-FABP mRNA in hybrids of Songliao black pig x Sus scrofa. [ Result] H-FABP expressed in all the twelve tissues including subcutaneous fat, abdominal fat, mammary gland, Iongissimus dorsi muscle, dorsal deltoid muscle, heart, liver, spleen, lung, kidney, ileum and duodenum. [ Conclusion] The wide distribution of H-FABP gene suggests that its functions are important and multiple.
基金Supported by the National Natural Science Foundation of China (No.20573093 and No.20434020).
文摘Prediction of vapor-liquid equilibrium (VLE) is extremely necessary to separate liquid mixture in chemical production, especially when the required experimental data are difficult to measure, or the measurement is not economical. The infinite dilution activities can be used to predict VLE. However, it needs both the ends of the activities that are difficult to obtain for many systems. In the present study, a new model is proposed for correlating the frequency shift of C-H stretching band of IR spectra over the whole concentration. Investigated mixtures in- clude water/2-propanol, water/N, N-dimethylformamide (DMF), water/methanol, water/ethanol, water/1, 4-dioxane, and water/dimethylsulfoxide (DMSO) systems. Simultaneous correlations of C--H frequency shift and VLE data are made. Furthermore, the VLE data were predicted with satisfactory results by the parameters obtained from IR spectra coupled with one ot the intinite chlution activity coefficients.
基金Project(3207049713)supported by the Scientific Research Foundation of Graduate School of Southeast University,China
文摘With the aim of achieving a high 5-hydroxymethylfurfural(HMF)yield from glucose with H-ZSM-5 catalyst at low cost,three inexpensive biphasic reaction systems,H2O?tetrahydrofuran(THF),H2O?2-methyltetrahydrofuran(MeTHF)and H2O?2-butanol,were discovered and proved to be particularly effective in promoting the formation of HMF from glucose over H-ZSM-5 zeolite.In order to determine the optimal process conditions,the effects of various experimental variables,such as reaction temperature,reaction time,catalyst dosage,volume of organic solvent,as well as inorganic salt type on glucose conversion to HMF in three systems were investigated in detail.It was found that under optimal reaction conditions,H2O?THF,H2O?2-butanol and H2O?MeTHF allowed the glucose dehydration process to achieve HMF yields of up to 61%,59%,and 50%,respectively.Moreover,in the three biphasic systems,the H-ZSM-5 catalyst was also demonstrated to maintain excellent stability.Thus,the catalytic approach proposed in this paper can be believed to have potential prospects for industrially efficient and low-cost production of HMF.
文摘Syrian hamster ernbryo(SHE) cells are irradiated by a particles emitted from Plutonium-238 in vtiro.Transfection frequencies of donor DNA derived from passaged cells,including monocloned cells from 20th passage cells,after irradiation are parallel with their tumorigenicity of donor cells. After trans formation, expressions of H-ras and c-myc genes are in the state of activation, which might be resulted from occurrence of mutation in H-ras gene and hypomethylation of c-myc gene respectively, even though no alteration was observed on their restriction fragment length polymorphisms(RELP) patterns of both genes. On the other hand,expression of p53 gene is also found to be in the state of activation in transformant, but no heavy staining of p53 protein appeared in the transformant-derived tumor with p53 specific McAb HD 200. This might be result from the partlal deletion of p53 cDNA in transformant by reverse transcriptional polymerase chain reaction(RT PCR). These results imply that activation of H-ras and c-myc genes coupled with inactivation of p53 turnor suppressor gene play important role in a particle-induced cell trans formation.
文摘Hexagonal boron nitride(h-BN)is a highly selective catalyst for oxidative dehydrogenation of light alkanes to produce the corresponding alkenes.Despite intense recent research effort,many aspects of the reaction mechanism,such as the observed supra-linear reaction order of alkanes,remain unresolved.In this work,we show that the introduction of a low concentration of propane in the feed of ethane oxidative dehydrogenation is able to enhance the C_(2)H_(6) conversion by 47%,indicating a shared reaction intermediate in the activation of ethane and propane.The higher activity of propane makes it the dominant radical generator in the oxidative co-dehydrogenation of ethane and propane(ODEP).This unique feature of the ODEP renders propane an effective probe molecule to deconvolute the two roles of alkanes in the dehydrogenation chemistry,i.e.,radical generator and substrate.Kinetic studies indicate that both the radical generation and the dehydrogenation pathways exhibit a first order kinetics toward the alkane partial pressure,leading to the observed second order kinetics of the overall oxidative dehydrogenation rate.With the steady-state approximation,a radical chain reaction mechanism capable of rationalizing observed reaction behaviors is proposed based on these insights.This work demonstrates the potential of ODEP as a strategy of both activating light alkanes in oxidative dehydrogenation on BN and mechanistic investigations.
文摘[Objective] The aim was to construct a recombinant pseudorabies virus expressing canine distemper virus H gene and investigate its biological characters.[Method] H gene of canine distemper virus(CDV)strain Onderstepoort was produced by RT-PCR,inserted into pcDNA3.1(+)vector to construct a expression cassette,which was then subcloned into transfer vector p8AA,prior to the insertion of LacZ expression cassette.The resulting new transfer vector was named as p8AAZH.Subsequently,p8AAZH was co-transfected with the genome of pseudorabies virus(PRV)Bartha-K61 into BHK-21 cells to enable gene recombination and virus package,and the virus solution was collected as cytopathic effect occurring.A series of procedures including blue plaque purification,PCR identification,observation under electron microscope and Western blot were carried out to screen the recombinant pseudorabies virus and identify the protein expression of target gene.Meanwhile,growth curve of the recombinant virus was determined in BHK-21 cells.[Result] The H gene had been inserted into the genome of Bartha-K61 strain,and RPRV-H was the same as Bartha-K61 in the one-step growth curve and cytopathic effect in BHK-21 cells.[Conclusion] The recombinant pseudorabies virus was constructed,and the insertion of H gene did not influence proliferation of recombinant virus,which laid a foundation for development of recombinant canine distemper virus vaccine.
文摘[Objective] This study was to develop a live vector vaccine of goat pox virus of Peste des petits ruminants(PPR). [Method] Using PCR amplification technique, PPR H gene was obtained, then ligated into pGEM-T easy vector; the recombinants were digested by Nhe Ⅰ and Hind Ⅲ, and ligated into pEGFP-N1-P7.5, yielding the recombinant vector pEGFP-N1-P7.5-H; next the expression cassette EGFP-N1-P7.5-H was first released from recombinant vector pEGFP-N1-P7.5-H by double digestion of Hind Ⅲ and Nhe Ⅰ and ligated into pUC119-TK that was digested by Kpn Ⅰ, yielding the transfer vector pUC119-TK-EGFP-P7.5-H. [Result] Identification and double enzyme digestion showed that the transfer vector pUC119-TK-EGFP-P7.5-H was correctly constructed. From the transfer vector transfected BHK-21 cells which infected GTPV AV41, specific fluorescence was observed at 48th h of transfection. [Conclusion] The construction of goat poxvirus live vector laid a foundation for the live vector vaccine of PPR vaccine.
文摘The Na+/H+ antiport genes namedTaNHX1andTaNHX2were cloned by screening a salt_stressed wheat cDNA library using rice Na+/H+ antiport cDNA fragment as the probe. Sequencing analysis showed thatTaNHX1was 2 029 bp in length and contained a complete ORF of 1 638 bp. TheTaNHX1encodes a polypeptide of 546 amino acids with a transmembrane domain DIFFIYLLPPI.TaNHX2was 1 693 bp in length consisting of a partial ORF followed by a 3′_UTR of 808 bp. The amino acid sequence of these two genes were about 70% identical to the known NHX genes from rice, Arabidopsis and Atriplex. A RT_PCR assay showed that the level ofTaNHX1transcripts was increased and reached a steady higher level in the seedlings after 3 h treatment with 400 mmol/L NaCl.
基金Supported by Chunhui Plan of Ministry of Education(Z2010101)Open Fund of Food Biotechnology Key Laboratory of Sichuan Province(SZJJ2009-014)Scientific Research Foundation of Xihua University(000022)~~
文摘[Objective] This study aimed to screen an Na+/H+ antiporter gene from the halophiles colonizing in the Dagong Ancient Brine Well in Zigong City, China, and then analyze the gene structure and properties of the protein encoded by this gene. [Method] Metagenomic DNA libraries of halophiles from the Dagong Ancient Brine Well were used for screening genes with Na+/H+ antiporter activity in antiporter-defi- cient E. coil KNabc strain by functional complementation. Then the start codon, stop codon, ORF, -35 region, -10 region and SD sequence of Na~/H+ antiporter gene, as well as the molecular weight, isoelectric point, hydrophobic region, transmembrane domain, phyletic evolution and salt resistance of protein encoded by the gene were investigated. [Result] A new Na+/H+ antiporter gene m-nha was obtained, which ,ren- dered the antiporter-negative mutant E. coil KNabc cells with both the resistance to Na+ and the ability to grow under alkaline conditions. [Conclusion] The structure and amino acid sequence of M-Nha was different from the previously reported Na+/H~ antiporters, and the m-nha gene disclosed from the Dagong Ancient Brine Well was identified as a novel Na+/H+ antiporter gene. This study was significant not only in helping us understand the salt tolerance of halophiles in ancient brine wells and develop and utilize the genes resource, but also in exploring new salt-tolerant genes.
基金Supported by Danone Institute China Diet Nutrition Research and Communication grant (2006)
文摘AIM:To investigate the differences in cultivable gut bacteria and peroxisome proliferator-activated receptor γ2(PPAR-γ2) gene Pro12Ala variation in obese and normal-weight Chinese people.METHODS:Using culture methods,the amounts of Escherichia coli,Enterococci,Bacteroides,Lactobacilli,Bif idobacteria and Clostridium perfringens(C.perfringens) in the feces of 52 obese participants [body mass index(BMI):≥ 28 kg/m2] and 52 participants of normalweight(BMI:18.5-24 kg/m2) were obtained.Study participants completed comprehensive questionnaires and underwent clinical laboratory tests.The polymerase chain reaction-restriction fragment length polymorphism(PCR-PFLP) assay was used to analyze PPAR-γ2 gene Pro12Ala variation.RESULTS:The obese group exhibited a lower amount of C.perfringens(6.54 ± 0.65 vs 6.94 ± 0.57,P = 0.001)and Bacteroides(9.81 ± 0.58 vs 10.06 ± 0.39,P = 0.012) than their normal-weight counterparts.No major differences were observed in Pro12Ala genotype distribution between the two groups;however,obese individuals with a Pro/Ala genotype had a signif icantly lower level of Bacteroides(9.45 ± 0.62 vs 9.93 ± 0.51,P = 0.027) than those with a Pro/Pro genotype.In addition,the obese group demonstrated a higher stool frequency(U = 975,P < 0.001) and a looser stool(U = 1062,P = 0.015) than the normal-weight group.CONCLUSION:Our results indicated interactions among cultivable gut flora,host genetic factors and obese phenotype and this might be helpful for obesity prevention.
基金supported by National High Technology Research and Development Program of China grant(2006AA1003062006AA100307)
文摘Vibrio parahaemolyticus (VP) is one of the pathogenic vibrios endangering net-cage cultured Pseudosciaena crocea,Fennerpenaeus chinensis, and shellfish in coastal areas of China. Several types of hemolysins produced by Vp have been characterized as major virulence factors.They are thermostable direct hemolysin (TDH),TDH-related hemolysin (TRH) and thermolabile hemolysin (TLH). In this study, we cloned tdh, trh, and tlh genes from the genome DNA of VP by polymerase chain reaction (PCR).We ligated the three genes into prokaryotic expression vector pET-28a (+),and transformed the recombinant plasmids into Es-cherichia coli BL21 (DE3). The expression of recombinant proteins was induced by isopropyl-β-D-thiogalacto-pyranoside (IPTG). The recombinant proteins were expressed in a form of inclusion bodies and thus purified with Ni-NTA affinity chromatography. Western blotting results showed that recombinant proteins,TDH, TRH and TLH, could be recognized by rabbit anti-VP serum. The three purified proteins were renatured by gradient dialysis.The renatured proteins exhibited hemolytic activity except for TLH in the presence of phosphatidylcholine. These results not only are helpful for better understanding these genes' functions under a single factor level, but also provide evidence for VP vaccine engineering.
基金Supported by Key Project of Nanjing Xiaozhuang University(2007NXY01)Natural Science Foundation of the Higher Education Institutions of Jiangsu Province (08KJD180011)College Student Practice and Innovation Training Program in Jiangsu Province(2009-2011)~~
文摘[Objective] The aim was to investigate AtNHX1 gene transformation in Brassica napus L. mediated by Agrobacterium tumefaciens. [Method] By using Agrobacterium-mediated method and cre/lox plant expression vector,the transformation of AtNHX1 gene of Na+/H+ antiporter in Brassica napus was studied. [Result] The regeneration rate of cotyledon with petiole was much higher than that of hypocotyl,thus,the cotyledon with petiole was selected as the recipient for transformation. After the cotyledon with petiole was soaked in bacterial solution (OD600=0.4) for 8-10 min,kanamycin-resistant green seeding percentage could reach 3.75%. [Conclusion] The PCR detection of kanamycin-resistant plants proved that NHX1 gene had been inserted into Brassica napus genome. And this research could provide a new way to improve the salt tolerance of Brassica napus.
文摘The Meyerhof and Hanna′s(M-H) method to estimate the ultimate bearing capacity of layered foundations was improved. The experimental results of the load tests in Tianjin New Harbor were compared with predictions with the method recommended by the code for the foundations of harbor engineering, i.e. Hansen′s method and the improved M-H method. The results of the comparisons implied that the code and the improved M-H method could give a better prediction.
文摘Cyclin-dependent kinase 7 (Cdk7) is the catalytic subunit of the metazoan Cdk-activating kinase (CAK). Activation of Cdk7 requires its association with a regulatory subunit, Cyclin H. Although the Cdk7/Cyclin H complex has been implicated in the regulation ofRNA polymerase in several species, the precise function of their orthologs in zebrafish has not been fully elucidated. In this study, we isolated from zebrafish blastula embryos two cDNAs encoding the orthologs of human Cyclin H and Cdk7, and examined the role of Cdk7/Cyclin H in zebrafish embryogenesis. Sequence analysis showed that the zebrafish Cyclin H and Cdk7 cDNAs encode proteins with 65% and 86% identity to the respective hu- man orthologs. RT-PCR and whole-mount in situ hybridization analyses of their expression in unfertilized eggs, embryos and organs of adult fish suggested that Cyclin H and Cdk7 messages are maternally loaded. Our data also showed that their transcripts were detected throughout development. Distribution of Cyclin H transcripts was found to be ubiquitous during early stages of development and become restricted to the anterior neural tube, brain, eyes, procreate tissues, liver and heart by 5 days post-fertilization. Expression of a dominant-negative form of Cyclin H delayed the onset of zygotic transcription in the early embryo, resulting in apoptosis at 5 hours post-fertilization and leading to sever defects in tis- sues normally exhibiting high levels of Cyclin H expression. These results implicate Cyclin H in the regulation of the transcriptional machinery during midblastula transition and suggest that it is an essential gene in early zebrafish larval development.
文摘The development of practical methods for the direct and selective C(sp^(3))‒H functionalization of hydrocarbons is an attractive topic in synthetic chemistry.Although the radical‐mediated hydrogen atom transfer(HAT)process has shown considerable potential in such reactions,it still faces fundamental problems associated with reactivity and selectivity.Herein,we report a convenient and economic approach to site‐selective C(sp^(3))‒H sulfonylation via photo‐induced HAT catalysis.Employing a conjugated polycyclic quinone as a direct HAT photocatalyst,commercially available inorganic sulfinates as the sulfonylation source,copper triflate as an inexpensive oxidant,a variety of toluene derivatives and cycloalkanes were converted into biologically and synthetically interesting sulfone products under mild conditions.The mechanistic studies reveal that the reaction sequence involves direct HAT‐induced radical formation and a subsequent copper‐mediated organometallic process for the C‒S bond formation.This method offers an appealing opportunity to furnish high value‐added products from abundant hydrocarbon starting materials and inexpensive reagents.
文摘Direct photocatalytic coupling of methanol to ethylene glycol(EG)is highly attractive.The reported photocatalysts for this reaction are all metal sulfide semiconductors,which may suffer from photocorrosion and have low stability.Thus,the development of non‐sulfide photocatalysts for efficient photocatalytic coupling of methanol to EG and H2 with high stability is urgent but extremely challenging.Herein,the first metal oxide photocatalyst,tantalum‐based semiconductor,is reported for preferential activation of C−H bond within methanol to form hydroxymethyl radical(•CH_(2)OH)and subsequent C−C coupling to EG.Compared with other metal oxide photocatalysts,such as TiO2,ZnO,WO_(3),Nb_(2)O_(5),tantalum oxide(Ta_(2)O_(5))is unique in that it can realize the selective photocatalytic coupling of methanol to EG.The co‐catalyst free nitrogen doped tantalum oxide(2%N‐Ta_(2)O_(5))shows an EG formation rate as high as 4.0 mmol gcat−1 h−1,about 9 times higher than that of Ta_(2)O_(5),with a selectivity higher than 70%.The high charge separation ability of nitrogen doped tantalum oxide plays a key role in its high activity for EG production.This catalyst also shows excellent stability longer than 160 h,which has not been achieved over the reported metal sulfide photocatalysts.Tantalum‐based photocatalyst is an environmentally friendly and highly stable candidate for photocatalytic coupling of methanol to EG.
基金supported by the National Natural Science Foundation of China(21421004,21573067,91545103)Program of Shanghai Academic Research Leader(17XD1401400)~~
文摘The oxidative dehydrogenation(ODH) of propane on monomeric VO3 supported by CeO2(111)(VO3/CeO 2(111)) is studied by periodic density functional theory calculations. Detailed energetic, structural, and electronic properties of these reactions are determined. The calculated activation energies of the breaking of the first and second C–H bonds of propane on the VO3/CeO2(111) catalyst are compared, and it is found that both the unique structural and electronic effects of the VO3/CeO2(111) catalyst contribute to the relatively easy rupture of the first C–H bond of the propane molecule during the ODH reaction. In particular, the so-called new empty localized states that are mainly constituted of O2 porbitals of the ceria-supported VO3 species are determined to be crucial for assisting the cleavage of the first C–H bond of the propane molecule. Following this they become occupied and the remaining C–H bonds become increasingly difficult to break owing to the increasing repulsion between the localized 4 felectrons at the Cecations, resulting in the adsorption of more H and other moieties. This work illustrates that CeO2-supported monomeric vanadium oxides can exhibit unique activity and selectivity for the catalytic ODH of alkanes to alkenes.