A series of extraction equilibrium experiments for aminobenzoic acid with di(2-ethylhexyl)phosphoric acid (D2EHPA) dissolved in n-octane or 1-octanol was carried out. The effects of aminobenzoic acid concentration,D2E...A series of extraction equilibrium experiments for aminobenzoic acid with di(2-ethylhexyl)phosphoric acid (D2EHPA) dissolved in n-octane or 1-octanol was carried out. The effects of aminobenzoic acid concentration,D2EHPA concentration and pH on the distribution ratio were discussed in detail. The infrared spectra of the organic phase loaded with solute illustrated that pH had little effect on the structure of the complex formed. There proceed ion association and cation-exchange.reaction in the extraction. An expression of the equilibrium distribution was proposed.展开更多
INTRODUCTION Nitrogen is a key component of soil organic matter. Only when we have succeeded in characterizing the major part of organic N-containing compounds will we be able to understand fully the transformation re...INTRODUCTION Nitrogen is a key component of soil organic matter. Only when we have succeeded in characterizing the major part of organic N-containing compounds will we be able to understand fully the transformation reactions in the soil and to use soil-N more efficiently. However, only about 1/ 4——1/ 2 of the total N in humic acid (HA), one of the major constituents of soil organic matter, can be accounted for as amino acids and amino sugars, and most of the remainder has still to be accounted for. It has been展开更多
The myosin heavy chain(MyHC)is one of the major structural and contracting proteins of muscle.We have isolated the cDNA clone encoding MyHC of the grass carp,Ctenopharyngodon idella. The sequence comprises 5 934 bp,in...The myosin heavy chain(MyHC)is one of the major structural and contracting proteins of muscle.We have isolated the cDNA clone encoding MyHC of the grass carp,Ctenopharyngodon idella. The sequence comprises 5 934 bp,including a 5 814 bp open reading frame encoding an amino acid sequence of 1 937 residues.The deduced amino acid sequence showed 69%homology to rabbit fast skeletal MyHC and 73%–76%homology to the MyHCs from the mandarin fish,walleye pollack,white croaker,chum salmon,and carp.The putative sequences of subfragment-1 and the light meromyosin region showed 61.4%–80%homology to the corresponding regions of other fish MyHCs.The tissue-specific and developmental stage-specific expressions of the MyHC gene were analyzed by quantitative real-time PCR.The MyHC gene showed the highest expression in the muscles compared with the kidney,spleen and intestine.Developmentally,there was a gradual increase in MyHC mRNA expression from the neural formation stage to the tail bud stage.The highest expression was detected in hatching larva.Our work on the MyHC gene from the grass carp has provided useful information for fish molecular biology and fish genomics.展开更多
The symmetrical body of flatfish larvae changes dramatically into an asymmetrical form after metamorphosis. The molecular mechanisms responsible for this change are poorly understood. As an initial step to clarify the...The symmetrical body of flatfish larvae changes dramatically into an asymmetrical form after metamorphosis. The molecular mechanisms responsible for this change are poorly understood. As an initial step to clarify these mechanisms, we used representational difference analysis of cDNA for the identification of genes active during metamorphosis in the Japanese flounder, Paralichthys olicaceus. One of the up-regulated genes was identified as creatine kinase muscle type 1 (CK-M1). Sequence analysis of CK-M1 revealed that it spanned 1 708 bp and encoded a protein of 382 amino acids. The overall amino acid sequence of the CK-M1 was highly conserved with those of other organisms. CK-M1 was expressed in adult fish tissues, including skeletal muscle, intestine and gill. Whole mount in-situ hybridization showed that the enhanced expression of CK-M1 expanded from the head to the whole body of larvae as metamorphosis progressed. Quantitative analysis revealed stage-specific high expression of CK-M1 during metamorphosis. The expression level of CK-M1 increased initially and peaked at metamorphosis, decreased afterward, and finally returned to the pre-metamorphosis level. This stage-specific expression pattern suggested strongly that CK-M1 was related to metamorphosis in the Japanese flounder. Its specific role in metamorphosis requires further study.展开更多
Antisense oligonucleotides(ASONs) and siRNAs have been applied extensively for the regulation of cellular and viral gene expression,and RNAi is currently one of the most promising new approaches for anti-tumor and ant...Antisense oligonucleotides(ASONs) and siRNAs have been applied extensively for the regulation of cellular and viral gene expression,and RNAi is currently one of the most promising new approaches for anti-tumor and anti-viral therapy.In order to improve bioactivity properties and physicochemical properties of siRNA,we synthesized a novel class of ASONs II-VII incorporated with amino-isonucleoside(isoA1 and isoA2) for investigation on basic physicochemical properties.Then we designed amino-isonucleoside(isoA1,isoA2 and isoT1) incorporated siRNA 2-7.Some meaningful results have been obtained from the physicochemical property experiments in ASONs.In RNAi potency experiments,we investigated RNAi potency of each strand of the siRNA.These amino-isonucleosides incorporated siRNAs showed promising bioactivity properties and had position specificity.Reduced off target effect from sense strand loading in siRNA application was observed.展开更多
文摘A series of extraction equilibrium experiments for aminobenzoic acid with di(2-ethylhexyl)phosphoric acid (D2EHPA) dissolved in n-octane or 1-octanol was carried out. The effects of aminobenzoic acid concentration,D2EHPA concentration and pH on the distribution ratio were discussed in detail. The infrared spectra of the organic phase loaded with solute illustrated that pH had little effect on the structure of the complex formed. There proceed ion association and cation-exchange.reaction in the extraction. An expression of the equilibrium distribution was proposed.
基金Project supported by the National Natural Science Foundation of China.
文摘INTRODUCTION Nitrogen is a key component of soil organic matter. Only when we have succeeded in characterizing the major part of organic N-containing compounds will we be able to understand fully the transformation reactions in the soil and to use soil-N more efficiently. However, only about 1/ 4——1/ 2 of the total N in humic acid (HA), one of the major constituents of soil organic matter, can be accounted for as amino acids and amino sugars, and most of the remainder has still to be accounted for. It has been
基金Supported by the National Natural Science Foundation of China(Nos.30972263,30771644)the Natural Science Foundation of HunanProvince(No.09jj6037)
文摘The myosin heavy chain(MyHC)is one of the major structural and contracting proteins of muscle.We have isolated the cDNA clone encoding MyHC of the grass carp,Ctenopharyngodon idella. The sequence comprises 5 934 bp,including a 5 814 bp open reading frame encoding an amino acid sequence of 1 937 residues.The deduced amino acid sequence showed 69%homology to rabbit fast skeletal MyHC and 73%–76%homology to the MyHCs from the mandarin fish,walleye pollack,white croaker,chum salmon,and carp.The putative sequences of subfragment-1 and the light meromyosin region showed 61.4%–80%homology to the corresponding regions of other fish MyHCs.The tissue-specific and developmental stage-specific expressions of the MyHC gene were analyzed by quantitative real-time PCR.The MyHC gene showed the highest expression in the muscles compared with the kidney,spleen and intestine.Developmentally,there was a gradual increase in MyHC mRNA expression from the neural formation stage to the tail bud stage.The highest expression was detected in hatching larva.Our work on the MyHC gene from the grass carp has provided useful information for fish molecular biology and fish genomics.
基金Supported by the National Natural Science Foundation of China (No. 30600455)the National High Technology Research and Development Program of China (No. 2006AA10A404)
文摘The symmetrical body of flatfish larvae changes dramatically into an asymmetrical form after metamorphosis. The molecular mechanisms responsible for this change are poorly understood. As an initial step to clarify these mechanisms, we used representational difference analysis of cDNA for the identification of genes active during metamorphosis in the Japanese flounder, Paralichthys olicaceus. One of the up-regulated genes was identified as creatine kinase muscle type 1 (CK-M1). Sequence analysis of CK-M1 revealed that it spanned 1 708 bp and encoded a protein of 382 amino acids. The overall amino acid sequence of the CK-M1 was highly conserved with those of other organisms. CK-M1 was expressed in adult fish tissues, including skeletal muscle, intestine and gill. Whole mount in-situ hybridization showed that the enhanced expression of CK-M1 expanded from the head to the whole body of larvae as metamorphosis progressed. Quantitative analysis revealed stage-specific high expression of CK-M1 during metamorphosis. The expression level of CK-M1 increased initially and peaked at metamorphosis, decreased afterward, and finally returned to the pre-metamorphosis level. This stage-specific expression pattern suggested strongly that CK-M1 was related to metamorphosis in the Japanese flounder. Its specific role in metamorphosis requires further study.
基金supported by the National Natural Science Foundation of China(20932001)the Ministry of Science and Technology of China (2006AA02Z144,2009ZX09503)
文摘Antisense oligonucleotides(ASONs) and siRNAs have been applied extensively for the regulation of cellular and viral gene expression,and RNAi is currently one of the most promising new approaches for anti-tumor and anti-viral therapy.In order to improve bioactivity properties and physicochemical properties of siRNA,we synthesized a novel class of ASONs II-VII incorporated with amino-isonucleoside(isoA1 and isoA2) for investigation on basic physicochemical properties.Then we designed amino-isonucleoside(isoA1,isoA2 and isoT1) incorporated siRNA 2-7.Some meaningful results have been obtained from the physicochemical property experiments in ASONs.In RNAi potency experiments,we investigated RNAi potency of each strand of the siRNA.These amino-isonucleosides incorporated siRNAs showed promising bioactivity properties and had position specificity.Reduced off target effect from sense strand loading in siRNA application was observed.
