The floatability of different crystalline structures of pyrrhotite(monoclinic and hexagonal) was studied.It is shown that the floatability of monoclinic and hexagonal has obvious difference,and that the flotation reco...The floatability of different crystalline structures of pyrrhotite(monoclinic and hexagonal) was studied.It is shown that the floatability of monoclinic and hexagonal has obvious difference,and that the flotation recovery of monoclinic pyrrhotite is larger than that of hexagonal pyrrhotite using different collectors.When butyl dithiophosphate is used as the collector,the recovery is larger than that by sodium butyl xanthate and sodium diethyl dithiocarbamate.At the pH values ranging from 6 to 9,monoclinic pyrrhotite can be floated well,and the flotation recovery is higher than 90%.Monoclinic and hexagonal pyrrhotites are more easily activated by Cu2+ in acidic conditions than in alkaline conditions.But Cu2+ cannot activate hexagonal pyrrhotite using sodium diethyldithiocarbamate as the collector.By the measurement of contact angle,it is indicated that monoclinic and hexagonal pyrrhotites float well and are easily activated by Cu2+ when dithiophosphate is used as the collector.Using sodium diethyl dithiocarbamate as a collector,the relationship between potential and pH range for pyrrhotite flotation is established.At pH 5,the optimal potential range for flotation of monoclinic pyrrhotite is about 125-580 mV(vs SHE),with the maximum flotation occurring at about 350 mV(vs SHE);the optimal potential range for flotation of hexagonal pyrrhotite is 200?580 mV(vs SHE),with the maximum flotation occurring at about 300 mV(vs SHE).展开更多
Objective： Although the kinase insert domain-containing receptor （KDR） gene play an very important role in the metastasis of cancer and is also as one of the molecular targets used in cancer therapy, mutation in th...Objective： Although the kinase insert domain-containing receptor （KDR） gene play an very important role in the metastasis of cancer and is also as one of the molecular targets used in cancer therapy, mutation in the tyrosine kinase （TK） domain of the KDR gene has not been reported. Here we detected the mutations and polymorphisms in the TK domain of KDR gene in human lung cancer patients and to give the basic evidence and clue for cancer prevention and target therapy. Methods： The entire sequence of exons 21, 22, 23 and 27 （which contain the coding sequence of tyrosine phosphorylation） in the TK domain of KDR gene in the patients with lung cancer and control healthy individuals were assayed by PCR and DNA sequencing. We also analyzed one non-coding single nucleotide polymorphisms （SNPs） in the KDR gene. Results： No mutations were found in exon 22, 23 and 27. One heterozygous mutation of c.＋2837 in exon 21 was found at a frequency of 2.08% （2/96） in the patients with lung cancer and none were detected in the healthy control individuals. The mutation was from a G to a A resulting in substitution of arginine with histidine residue. Conclusion： Our data suggested that we should focus on the mutation or SNP in the other regions or the expression levels of KDR gene, and the function of c.＋2837 mutation of KDR .qene may be needed further study in the future.展开更多
Clip domain serine proteases （cSPs） and their homologs （SPHs） play an important role in various biological processes that are essential components of extracellular signaling cascades, especially in the innate immu...Clip domain serine proteases （cSPs） and their homologs （SPHs） play an important role in various biological processes that are essential components of extracellular signaling cascades, especially in the innate immune responses of invertebrates. Here, polymorphisms of PtcSP and PtSPH from the swimming crab Portunus tritubereulatus were investigated to explore their association with resistance/ susceptibility to Vibrio alginolyticus. Polymorphic loci were identified using Clustal X, and characterized with SPSS 16.0 software, and then the significance of genotype and allele frequencies between resistant and susceptible stocks was determined by a Zz test. A total of 109 and 77 single nucleotide polymorphisms （SNPs） were identified in the genomic fragments of PtcSP and PtSPH, respectively. Notably, nearly half of PtSPH polymorphisms were found in the non-coding exon 1. Fourteen SNPs investigated were significantly associated with susceptibility/resistance to I1. alginolyticus （P〈0.05）. Among them, eight SNPs were observed in introns, and one synonymous, four non-synonymous SNPs and one ins-del were found in coding exons. In addition, five simple sequence repeats （SSRs） were detected in intron 3 of PtcSP. Although there was no statistically significant difference of allele frequencies, the SSRs showed different polymorphic alleles on the basis of the repeat number between resistant and susceptible stocks. After fiarther validation, polymorphisms investigated here might be applied to select potential molecular markers ofP. trituberculatus with resistance to I1. alginolyticus.展开更多
Objective N-methyl-D-aspartate（NMDA）receptor has been indicated to be involved in the pathogenesis of Alzheimer’s disease（AD）.The NMDA receptor subunit 2b（NR2B）has attracted more attention due to its characteri...Objective N-methyl-D-aspartate（NMDA）receptor has been indicated to be involved in the pathogenesis of Alzheimer’s disease（AD）.The NMDA receptor subunit 2b（NR2B）has attracted more attention due to its characteristic distribution and selective reduction in AD brain.The present study aimed to explore the association between NMDA gene polymorphism and AD.Methods A total of 63 AD patients and 68 normal controls in Shanghai city were employed in this study.Genotype of C2664T variant（rs1806201）in the exon13 of GRIN2B gene was determined by gene sequencing. Results Among AD patients,15（23.6%）subjects were identified as C/C genotype,and 35（55.6%）were identified as C/T genotype.The left 13（20.6%）subjects were identified as T/T genotype.In normal controls,15（22.1%）subjects were identified as C/C genotype,39（57.4%）as C/T genotype and 14（20.6%）as T/T genotype.The distribution frequency of neither GRIN2B C2664T genotype（P=0.895）nor allele（P=0.790）was significantly different between AD patients and normal controls,even when the subjects were stratified by gender and age of disease onset in AD patients.Conclusion The results suggest that there is no relation between GRIN2B C2664T polymorphism and AD in Chinese Han population of Shanghai City.展开更多
The detection of single amino-acid variants （SAVs） usually depends on single-nucleotide polymorphisms （SNPs） database. Here, we describe a novel method that discovers SAVs at proteome level independent of SNPs dat...The detection of single amino-acid variants （SAVs） usually depends on single-nucleotide polymorphisms （SNPs） database. Here, we describe a novel method that discovers SAVs at proteome level independent of SNPs data. Using mass spectrometry-based de novo sequencing algorithm, peptide-candidates are identified and compared with theoretical protein database to generate SAVs under pairing strategy, which is followed by database re-searching to control false discovery rate. in human brain tissues, we can confidently identify known and novel protein variants with diverse origins. Combined with DNA/RNA sequencing, we verify SAVs derived from DNA mutations, RNA alternative splicing, and unknown post-transcriptional mechanisms. Furthermore, quantitative analysis in human brain tissues reveals several tissue-specific differential expressions of SAVs. This approach provides a novel access to high-throughput detection of protein variants, which may offer the potential for clinical biomarker discovery and mechanistic research.展开更多
基金Project(50774094) supported by the National Natural Science Foundation of China
文摘The floatability of different crystalline structures of pyrrhotite(monoclinic and hexagonal) was studied.It is shown that the floatability of monoclinic and hexagonal has obvious difference,and that the flotation recovery of monoclinic pyrrhotite is larger than that of hexagonal pyrrhotite using different collectors.When butyl dithiophosphate is used as the collector,the recovery is larger than that by sodium butyl xanthate and sodium diethyl dithiocarbamate.At the pH values ranging from 6 to 9,monoclinic pyrrhotite can be floated well,and the flotation recovery is higher than 90%.Monoclinic and hexagonal pyrrhotites are more easily activated by Cu2+ in acidic conditions than in alkaline conditions.But Cu2+ cannot activate hexagonal pyrrhotite using sodium diethyldithiocarbamate as the collector.By the measurement of contact angle,it is indicated that monoclinic and hexagonal pyrrhotites float well and are easily activated by Cu2+ when dithiophosphate is used as the collector.Using sodium diethyl dithiocarbamate as a collector,the relationship between potential and pH range for pyrrhotite flotation is established.At pH 5,the optimal potential range for flotation of monoclinic pyrrhotite is about 125-580 mV(vs SHE),with the maximum flotation occurring at about 350 mV(vs SHE);the optimal potential range for flotation of hexagonal pyrrhotite is 200?580 mV(vs SHE),with the maximum flotation occurring at about 300 mV(vs SHE).
基金Supported by the grants from the National Natural Science Foundation of China (No. 30772531)Guangdong Provincial Medical Science and Technology Research Foundation (No. B2006001)China Postdoctoral Science Foundation (No. 20060400212)
文摘Objective： Although the kinase insert domain-containing receptor （KDR） gene play an very important role in the metastasis of cancer and is also as one of the molecular targets used in cancer therapy, mutation in the tyrosine kinase （TK） domain of the KDR gene has not been reported. Here we detected the mutations and polymorphisms in the TK domain of KDR gene in human lung cancer patients and to give the basic evidence and clue for cancer prevention and target therapy. Methods： The entire sequence of exons 21, 22, 23 and 27 （which contain the coding sequence of tyrosine phosphorylation） in the TK domain of KDR gene in the patients with lung cancer and control healthy individuals were assayed by PCR and DNA sequencing. We also analyzed one non-coding single nucleotide polymorphisms （SNPs） in the KDR gene. Results： No mutations were found in exon 22, 23 and 27. One heterozygous mutation of c.＋2837 in exon 21 was found at a frequency of 2.08% （2/96） in the patients with lung cancer and none were detected in the healthy control individuals. The mutation was from a G to a A resulting in substitution of arginine with histidine residue. Conclusion： Our data suggested that we should focus on the mutation or SNP in the other regions or the expression levels of KDR gene, and the function of c.＋2837 mutation of KDR .qene may be needed further study in the future.
基金Supported by the National Natural Science Foundation of China(Nos.41206147,31302187)the Scientific and Technological Innovation Project Financially Supported by Qingdao National Laboratory for Marine Science and Technology(No.2015ASKJ02)
文摘Clip domain serine proteases （cSPs） and their homologs （SPHs） play an important role in various biological processes that are essential components of extracellular signaling cascades, especially in the innate immune responses of invertebrates. Here, polymorphisms of PtcSP and PtSPH from the swimming crab Portunus tritubereulatus were investigated to explore their association with resistance/ susceptibility to Vibrio alginolyticus. Polymorphic loci were identified using Clustal X, and characterized with SPSS 16.0 software, and then the significance of genotype and allele frequencies between resistant and susceptible stocks was determined by a Zz test. A total of 109 and 77 single nucleotide polymorphisms （SNPs） were identified in the genomic fragments of PtcSP and PtSPH, respectively. Notably, nearly half of PtSPH polymorphisms were found in the non-coding exon 1. Fourteen SNPs investigated were significantly associated with susceptibility/resistance to I1. alginolyticus （P〈0.05）. Among them, eight SNPs were observed in introns, and one synonymous, four non-synonymous SNPs and one ins-del were found in coding exons. In addition, five simple sequence repeats （SSRs） were detected in intron 3 of PtcSP. Although there was no statistically significant difference of allele frequencies, the SSRs showed different polymorphic alleles on the basis of the repeat number between resistant and susceptible stocks. After fiarther validation, polymorphisms investigated here might be applied to select potential molecular markers ofP. trituberculatus with resistance to I1. alginolyticus.
基金supported by the Key Project of Shanghai Science and Technology Committee(No.08411951100,10ZR1425800)the National Major Special Project of Science and Technology of Ministry of Science and Technology,China(No.2008ZX09312-014,2008ZX09312-003)
文摘Objective N-methyl-D-aspartate（NMDA）receptor has been indicated to be involved in the pathogenesis of Alzheimer’s disease（AD）.The NMDA receptor subunit 2b（NR2B）has attracted more attention due to its characteristic distribution and selective reduction in AD brain.The present study aimed to explore the association between NMDA gene polymorphism and AD.Methods A total of 63 AD patients and 68 normal controls in Shanghai city were employed in this study.Genotype of C2664T variant（rs1806201）in the exon13 of GRIN2B gene was determined by gene sequencing. Results Among AD patients,15（23.6%）subjects were identified as C/C genotype,and 35（55.6%）were identified as C/T genotype.The left 13（20.6%）subjects were identified as T/T genotype.In normal controls,15（22.1%）subjects were identified as C/C genotype,39（57.4%）as C/T genotype and 14（20.6%）as T/T genotype.The distribution frequency of neither GRIN2B C2664T genotype（P=0.895）nor allele（P=0.790）was significantly different between AD patients and normal controls,even when the subjects were stratified by gender and age of disease onset in AD patients.Conclusion The results suggest that there is no relation between GRIN2B C2664T polymorphism and AD in Chinese Han population of Shanghai City.
文摘The detection of single amino-acid variants （SAVs） usually depends on single-nucleotide polymorphisms （SNPs） database. Here, we describe a novel method that discovers SAVs at proteome level independent of SNPs data. Using mass spectrometry-based de novo sequencing algorithm, peptide-candidates are identified and compared with theoretical protein database to generate SAVs under pairing strategy, which is followed by database re-searching to control false discovery rate. in human brain tissues, we can confidently identify known and novel protein variants with diverse origins. Combined with DNA/RNA sequencing, we verify SAVs derived from DNA mutations, RNA alternative splicing, and unknown post-transcriptional mechanisms. Furthermore, quantitative analysis in human brain tissues reveals several tissue-specific differential expressions of SAVs. This approach provides a novel access to high-throughput detection of protein variants, which may offer the potential for clinical biomarker discovery and mechanistic research.
