429 results on '"Liu, L. X."'
Search Results
202. Myostatin mRNA expression and its association with body weight and carcass traits in Yunnan Wuding chicken.
- Author
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Liu LX, Dou TF, Li QH, Rong H, Tong HQ, Xu ZQ, Huang Y, Gu DH, Chen XB, Ge CR, and Jia JJ
- Subjects
- Animals, Avian Proteins genetics, Avian Proteins metabolism, Breeding, Chickens metabolism, Female, Gene Expression Regulation, Male, Muscle Development, Myostatin metabolism, Organ Specificity, Phenotype, Quantitative Trait Loci, Body Weight genetics, Chickens genetics, Chickens growth & development, Gene Expression, Myostatin genetics
- Abstract
Myostatin (MSTN) is expressed in the myotome and developing skeletal muscles, and acts to regulate the number of muscle fibers. Wuding chicken large body, developed muscle, high disease resistance, and tender, delicious meat, and are not selected for fast growth. Broiler chickens (Avian broiler) are selected for fast growth and have a large body size and high muscle mass. Here, 240 one-day-old chickens (120 Wuding chickens and 120 broilers) were examined. Twenty chickens from each breed were sacrificed at days 1, 30, 60, 90, 120, and 150. Breast and leg muscle samples were collected within 20 min of sacrifice to investigate the effects of MSTN gene expression on growth performance and carcass traits. Body weight, carcass traits, and skeletal muscle mass in Wuding chickens were significantly (P < 0.05) lower than those in broiler chickens at all time points. Breast muscle MSTN mRNA was lower in Wuding chickens than in broilers before day 30 (P < 0.05). After day 30, breast muscle MSTN expression was higher in Wuding chicken than in broilers (P < 0.05). Leg muscle MSTN mRNA expression was higher in Wuding chicken than in broilers at all ages except for day 60 (P < 0.05). Correlation analysis revealed that breast muscle MSTN expression has a greater effect in slow growing Wuding chickens than in the fast growing broilers. In contract, leg muscle MSTN mRNA level has a greater effect in broilers than in Wuding chickens. MSTN regulates growth performance and carcass traits in chickens.
- Published
- 2016
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203. Effect of swine leukocyte antigen-DQA gene variation on diarrhea in Large White, Landrace, and Duroc piglets.
- Author
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Yang QL, Huang XY, Zhao SG, Liu LX, Zhang SW, Huang WZ, and Gun SB
- Subjects
- Alleles, Animals, Disease Resistance genetics, Gene Frequency, Genotype, Histocompatibility Antigens Class I, Polymorphism, Single Nucleotide, Sequence Analysis, DNA, Swine genetics, Diarrhea genetics, Exons, Histocompatibility Antigens Class II genetics, Sus scrofa genetics, Swine Diseases genetics
- Abstract
Piglet diarrhea is one of the most common factors that affects the benefits of the swine industry. Although recent studies have shown that exon 2 of SLA-DQA is associated with piglet resistance to diarrhea, contributions of genetic variation in the additional exon coding regions of this gene remain unclear. Here, we investigated variation in exons 1, 3 and 4 of the SLA-DQA gene and evaluated their effects on diarrheal infection in 425 suckling piglets. No variation was identified in exon 1. In exon 3, there were eight alleles detected, generated by 14 single nucleotide polymorphisms (SNPs) and three nucleotide deletions, eight SNPs being newly identified. Four allele sequences and three SNPs were identified in exon 4, only one SNP being newly identified. Statistical analysis showed that the genotypes of exon 3 are significantly associated with piglet diarrhea; indeed, genotypes DQA*wb01/wb02 and wb04/wb05 are clearly associated with resistance to piglet diarrhea, as they have the lowest probabilities of infection (P < 0.05). However, no significant association was found between the genotypes of exon 4 and diarrhea (P > 0.05). These results provide important new information concerning the level of genetic diversity at the SLA-DQA locus and suggest that further genetic association studies of piglet diarrhea resistance should include analyses of both exons 2 and 3 of this locus., (© 2016 Stichting International Foundation for Animal Genetics.)
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- 2016
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204. Comparison and analysis of Wuding and avian chicken skeletal muscle satellite cells.
- Author
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Tong HQ, Jiang ZQ, Dou TF, Li QH, Xu ZQ, Liu LX, Gu DH, Rong H, Huang Y, Chen XB, Jois M, Te Pas MF, Ge CR, and Jia JJ
- Subjects
- Animals, Cell Differentiation, Cell Proliferation, Cell Shape, Cells, Cultured, Fluorescent Antibody Technique, Muscle Development, Real-Time Polymerase Chain Reaction, Satellite Cells, Skeletal Muscle metabolism, Chickens metabolism, Satellite Cells, Skeletal Muscle cytology
- Abstract
Chicken skeletal muscle satellite cells are located between the basement membrane and the sarcolemma of mature muscle fibers. Avian broilers have been genetically selected based on their high growth velocity and large muscle mass. The Wuding chicken is a famous local chicken in Yunnan Province that undergoes non-selection breeding and is slow growing. In this study, we aimed to explore differences in the proliferation and differentiation properties of satellite cells isolated from the two chicken breeds. Using immunofluorescence, hematoxylin-eosin staining and real-time polymerase chain reaction analysis, we analyzed the in vitro characteristics of proliferating and differentiating satellite cells isolated from the two chicken breeds. The growth curve of satellite cells was S-shaped, and cells from Wuding chickens entered the logarithmic phase and plateau phase 1 day later than those from Avian chicken. The results also showed that the two skeletal muscle satellite cell lines were positive for Pax7, MyoD and IGF-1. The expression of Pax7 followed a downward trend, whereas that of MyoD and IGF-1 first increased and subsequently decreased in cells isolated from the two chickens. These data indicated that the skeletal muscle satellite cells of Avian chicken grow and differentiate faster than did those of Wuding chickens. We suggest that the methods of breeding selection applied to these breeds regulate the characteristics of skeletal muscle satellite cells to influence muscle growth.
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- 2016
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205. Genetic association of sequence variation in exon 3 of the swine leukocyte antigen-DQA gene with piglet diarrhea in Large White, Landrace, and Duroc piglets.
- Author
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Yang QL, Huang XY, Kong JJ, Zhao SG, Liu LX, and Gun SB
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Breeding, Diarrhea genetics, Disease Resistance, Exons, Female, Genetic Association Studies, Genetic Predisposition to Disease, Histocompatibility Antigens Class I, Male, Polymorphism, Single-Stranded Conformational, Swine, Diarrhea veterinary, Histocompatibility Antigens Class II genetics, Sus scrofa genetics, Swine Diseases genetics
- Abstract
Piglet diarrhea is one of the primary factors that affects the benefits of the swine industry. Recent studies have shown that exon 2 of the swine leukocyte antigen-DQA gene is associated with piglet resistance to diarrhea; however, the contributions of additional exon coding regions of this gene remain unclear. Here, we detected and sequenced variants in the exon 3 region and examined their associations with diarrhea infection in 425 suckling piglets using the polymerase chain reaction-single-strand conformational polymorphism and sequencing analysis. The results revealed that exon 3 of the swine leukocyte antigen-DQA gene is highly polymorphic and pivotal to both diarrhea susceptibility and resistance in piglets. We identified 14 genotypes (AA, AB, BB, BC, CC, EE, EF, BE, BF, CF, DD, DH, GG, and GF) and eight alleles (A-H) that were generated by 14 nucleotide variants, eight of which were novel, and three nucleotide deletions. Statistical analyses revealed that the genotypes AB and EF were associated with resistance to diarrheal disease (P < 0.05), and the genotype DD may contribute to diarrhea susceptibility but was unique to Large White pigs (P > 0.05). These results elucidate the genetic and immunological background to piglet diarrhea, and provide useful information for resistance breeding programs., Competing Interests: The authors declare no conflict of interest.
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- 2016
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206. [Treatment experience on ICU patients with percutaneous dilational tracheotomy and subsequent delayed bleeding].
- Author
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Liu LX, Li JD, Luo XZ, and Chi RB
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- 2016
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207. Serum zinc levels in 368 patients with oral mucosal diseases: A preliminary study.
- Author
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Bao ZX, Yang XW, Shi J, and Liu LX
- Subjects
- Burning Mouth Syndrome pathology, Case-Control Studies, Humans, Lichen Planus, Oral pathology, Stomatitis, Aphthous pathology, Mouth Diseases pathology, Zinc blood
- Abstract
Background: The aim of this study was to assess the serum zinc levels in patients with common oral mucosal diseases by comparing these to healthy controls., Material and Methods: A total of 368 patients, which consisted of 156 recurrent aphthous stomatitis (RAS) patients, 57 oral lichen planus (OLP) patients, 55 burning mouth syndrome (BMS) patients, 54 atrophic glossitis (AG) patients, 46 xerostomia patients, and 115 sex-and age-matched healthy control subjects were enrolled in this study. Serum zinc levels were measured in all participants. Statistical analysis was performed using a one-way ANOVA, t-test, and Chi-square test., Results: The mean serum zinc level in the healthy control group was significantly higher than the levels of all other groups (p < 0.001). No individual in the healthy control group had a serum zinc level less than the minimum normal value. However, up to 24.7% (13/54) of patients with AG presented with zinc deficiency, while 21.2% (33/156) of patients with RAS, 16.4% (9/55) of patients with BMS, 15.2% (7/46) of patients with xerostomia, and 14.0% (8/57) of patients with OLP were zinc deficient. Altogether, the zinc deficiency rate was 19.02% (70/368) in the oral mucosal diseases (OMD) group (all patients with OMD). The difference between the OMD and healthy control group was significant (p <0.001). Gender differences in serum zinc levels were also present, although not statistically significant., Conclusions: Zinc deficiency may be involved in the pathogenesis of common oral mucosal diseases. Zinc supplementation may be a useful treatment for oral mucosal diseases, but this requires further investigation; the optimal serum level of zinc, for the prevention and treatment of oral mucosal diseases, remains to be determined.
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- 2016
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208. Population phylogenomic analysis and origin of mitochondrial DNA in Chinese domestic pig.
- Author
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Huo JH, Wei QP, Wan MC, Liu LX, Hu LF, Zhou QY, Xiong LG, Yang Q, and Wu YP
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- Animals, Animals, Domestic genetics, Base Sequence, China, Genetic Variation genetics, Genome Size, Haplotypes genetics, Molecular Sequence Data, Phylogeny, Sus scrofa classification, DNA, Mitochondrial genetics, Genome, Mitochondrial genetics, Mitochondria genetics, Sequence Analysis, DNA veterinary, Sus scrofa genetics
- Abstract
The genetic diversity of eight domestic pigs was analyzed using a hypervariable fragment in the mitochondrial (mt) DNA control region; a portion of the hypervariable control region (515 bp) was sequenced from 153 samples. Haplotype diversity and nucleotide diversity in Yushan black pig populations were significantly higher than other populations (p < 0.01). A neighbor-joining tree was constructed from domestic pig mtDNA and five wild pigs. The results indicate that there are only small differences among individual pigs from different regions. Networks of the domestic pigs were constructed to better visualize the relationships between sequences. Each core haplotype was surrounded by a star-like pattern, consistent with recent population expansion.
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- 2016
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209. Cloning, sequence characterization, and expression patterns of members of the porcine TSSK family.
- Author
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Wang P, Huo HL, Wang SY, Miao YW, Zhang YY, Zhang QL, Li FQ, Liu LX, Li WZ, Zeng YZ, Huo JL, and Xiao H
- Subjects
- Adult, Amino Acid Sequence genetics, Animals, Cloning, Molecular, Gene Expression Regulation, Developmental, Humans, Male, Mice, Organ Specificity genetics, Phylogeny, Protein Serine-Threonine Kinases biosynthesis, Seminal Vesicles growth & development, Seminal Vesicles metabolism, Swine, Swine, Miniature, Testis metabolism, Multigene Family genetics, Protein Serine-Threonine Kinases genetics, Spermatogenesis genetics, Testis growth & development
- Abstract
Testis-specific serine kinases (TSSKs) are a family of serine/threonine kinases highly expressed in the testes that are responsible for regulating many spermatogenesis-related protein activities. Mutations in this family have a positive relationship with oligospermia and azoospermia in human and mouse. Here, five members of the TSSK family from a Banna mini-pig inbred line (BMI) were cloned, sequenced, and characterized. The full-length coding sequences of BMI TSSKs varied from 807 (TSSK3) to 1095 bp (TSSK1) and encoded 268 to 364 amino acids with molecular weights in the range 30.11 to 41.34 kDa. Following comparison with TSSK4 genes in other species, BMI TSSK4 was found to contain three alternatively spliced variants, inform1, inform 3, and inform 4. BMI TSSK1 and TSSK2 are co-localized on the Sus scrofa chromosome (SSC) 14, and consist of a single exon; TSSK3, TSSK4, and TSSK6 are on SSC6, SSC7, and SSC2, and consist of two, four, and one exon, respectively. Multiple protein sequence alignment and phylogenetic analysis showed that the regions spanning the S_TKc domains were more conserved between pig and other animals: with TSSK1 and TSSK2 and TSSK3 and TSSK6 displaying the greatest degree of homology across species, and the TSSK4 protein clearly distinct from other members. Multi-tissue RT-PCR showed BMI TSSK1, TSSK3, and TSSK4 were only expressed in the testes and seminal vesicle, TSSK2 was confined to testes only, while TSSK6 was expressed widely in adult tissues but was highest in the testes.
- Published
- 2015
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210. Performance of peanut mutants and their offspring generated from mixed high-energy particle field radiation and tissue culture.
- Author
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Wang JS, Qiao LX, Zhao LS, Wang P, Guo BT, Liu LX, and Sui JM
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- Arachis metabolism, Germination genetics, Germination radiation effects, Mutation radiation effects, Phenotype, Plant Breeding, Plant Growth Regulators metabolism, Seeds genetics, Seeds metabolism, Seeds radiation effects, Arachis genetics, Arachis radiation effects
- Abstract
To develop new ways to breed peanut, we irradiated seeds of the Luhua 11 cultivar with a mixed high-energy particle field at different doses. The embryonic leaflets were extracted as explants and incubated on somatic embryo induction medium and then on somatic embryo germination and regeneration medium. After being grafted, the M1-generation plants were transplanted, and seeds from each M1-generation plant were harvested. In the following year, the M2-generation seeds were planted separately. Some M2-generation plants showed distinct character segregation relative to the mutagenic parent in terms of vigor, fertility, plant height, branch number, and pod size and shape. M2-generation plants that had a high pod weight per plant tended to produce M3-generation offspring that also had a high pod weight per plant, much higher than that of the mutagenic parent, Luhua 11. M4-generation seeds varied greatly in quality, and 35 individuals with an increased fat content (>55%) were obtained. Overall, the results indicate that the combination of mutagenesis via mixed high-energy particle field exposure and tissue culture is promising for peanut breeding.
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- 2015
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211. Association between polymorphisms of the swine MHC-DQA gene and diarrhoea in three Chinese native piglets.
- Author
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Liu LX, Zhao SG, Lu HN, Yang QL, Huang XY, and Gun SB
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- Alleles, Animals, Exons, Gene Frequency, Genetics, Population, Genotype, Histocompatibility Antigens Class I, Histocompatibility Antigens Class II genetics, Molecular Sequence Data, Polymerase Chain Reaction, Polymorphism, Single-Stranded Conformational, Swine Diseases, Diarrhea veterinary, Genes, MHC Class II, Genetic Association Studies, Genetic Predisposition to Disease, Polymorphism, Genetic, Swine genetics
- Abstract
Swine leucocyte antigen (SLA) is a highly polymorphic multigene family that plays a crucial role in swine immune response and disease resistance. Here, we identified polymorphisms and gene variations of SLA-DQA exon 2 using polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and DNA sequencing analysis, and further investigated the correlation between the polymorphisms and piglet diarrhoea in three Chinese native pig breeds (Bamei, Juema and Gansu Black pigs). Consequently, 12 genotypes and 8 alleles including two novel alleles were detected. Nucleotide polymorphism was compared with the actual functional polymorphism in the peptide-binding region (PBR), binding pockets P1, P6 and P9, and the antigen-binding groove, variations in the antigen-binding groove of alleles DQA*01xa01, DQA*01xa03, DQA*01xb01, DQA*We02, DQA*03xb03 and DQA*wy06 were higher than alleles DQA*03xa01 and DQA*03xa03, while amino acid variations in peptide-binding pockets of allele DQA*03xa03 were most abundant among all alleles. The results of association analysis showed the diarrhoea score of Gansu Black pigs (-0.08 ± 0.78) was significantly higher than Bamei and Juema pigs (P < 0.01), and genotype DQA*03xa0103xa01 (0.39 ± 0.54) was significantly higher relative to other genotypes (P < 0.01), while that of genotype DQA*03xa0303xa03 (-1.31 ± 0.88) was markedly lower than scores obtained with genotypes DQA*03xa0103xa01 and DQA*03xa0101xa01 (P < 0.01), as well as DQA*01xa0101xa01 (P < 0.05), indicating that amino acid variations in the peptide-binding pockets play a more important role than the antigen-binding groove in piglet diarrhoea resistance. Further studies on other SLA molecules of native pigs are required to validate the link between this gene complex and diarrhoea., (© 2015 John Wiley & Sons Ltd.)
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- 2015
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212. [Transcriptome analysis of human breast cancer cell lines MCF-7 and MDA-MB- 435 by RNA-seq].
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Wang CH, Gao XJ, Liao SY, Feng JX, Luo B, and Liu LX
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- Breast Neoplasms pathology, Cell Line, Tumor, Female, Gene Expression Profiling, Humans, Neoplasm Metastasis, Sequence Analysis, RNA, Breast Neoplasms genetics, Breast Neoplasms metabolism, Gene Expression Regulation, Neoplastic, RNA, Neoplasm biosynthesis, RNA, Neoplasm genetics, Transcriptome
- Abstract
The transcriptomic profiles of human breast cancer cell lines MCF-7 and MDA-MB-435 were investigated using the next-generation RNA sequencing (RNA-Seq). The DESeq package was used to screen the differentially expressed transcripts. A total of 229 genes with a significantly differential expression in MDA-MB-435 cells as compared with MCF-7 cells were obtained. Annotation of the biological functions of these genes through the Database for Annotation, Visualization and Integrated Discovery (DAVID) v6.7 demonstrated that the 229 differentially expressed genes were mainly implicated in the biological functions related to cell adhesion and motion, antigen processing and presentation (via MHC class II), hormone response, extracellular structure organization, tissue remodeling, and cell proliferation regulation. Analysis of the individual genes demonstrated that MDA-MB-435 cells exhibited a higher tendency to metastasis and antigen processing and presentation, and lower ability to hormone response. Twenty most abundant transcripts in MDA-MB-435 cells, such as VIM, TNC, and CD74, represent its high potential for metastasis. Besides the genes previously reported to be involved in tumor metastasis and development, genes newly identified in this study could provide new clues for the diagnosis and prognosis of aggressive breast cancers.
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- 2015
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213. Otx1 promotes basal dendritic growth and regulates intrinsic electrophysiological and synaptic properties of layer V pyramidal neurons in mouse motor cortex.
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Zhang YF, Liu LX, Cao HT, Ou L, Qu J, Wang Y, and Chen JG
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- Action Potentials physiology, Animals, Cell Size, Electric Stimulation, Electroporation, Excitatory Postsynaptic Potentials physiology, Gene Transfer Techniques, Lysine analogs & derivatives, Mice, Inbred C57BL, Mice, Knockout, Motor Cortex cytology, Mutation, Otx Transcription Factors genetics, Patch-Clamp Techniques, Pyramidal Cells cytology, Tissue Culture Techniques, Dendrites physiology, Motor Cortex physiology, Otx Transcription Factors metabolism, Pyramidal Cells physiology, Synapses physiology
- Abstract
The transcription factor Otx1 is specifically expressed in layer V pyramidal cells (L5PCs) in the cerebral cortex. Otx1 null mutant mice have a defect in the developmental axon pruning of L5PCs and show epileptic seizures. However, the role of Otx1 in electrophysiology, morphology and synaptology of the cortical neurons has not been fully investigated. This study examines the influences of Otx1 on neuronal properties of L5PCs by loss- and gain-of-function approaches. Mice with an Otx1-null mutation had decreased structural measurements of basal dendrites in L5PCs. In contrast, the size of basal dendrites was increased in the Otx1-over-expressed pyramidal cells (PCs) in L2/3 where the gene normally does not express. PCs showed burst and non-burst firing patterns of action potentials. The proportion of burst firing neurons was reduced in the Otx1 mutant but increased in the neurons over-expressing Otx1. Although the burst firing population decreased, the proportion of those bursting neurons with a low threshold increased in the Otx1 mutant mice. Moreover, excitatory facilitating synaptic connections formed between L5PCs were predominant in the Otx1 mutant mice, which greatly contrasted with the predominant depressing synaptic connections in the controls. Taken together, it suggests an enhanced activity of neuronal network in the cortex of Otx1 mutant mice. These data indicate that the Otx1 expression is essential for the normal development of dendritic morphology, intrinsic electrophysiology and synaptic dynamics of L5PCs. This study provides new insights into molecular mechanisms underlying the spatial and temporal regulation of neuronal and synaptic properties of L5PCs, and improves our understanding on the generation of epileptic seizures., (Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.)
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- 2015
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214. Isolation, molecular cloning, and characterization of a novel porcine lymphotoxin beta receptor gene.
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Zhang YY, Wang SY, Miao YW, Li WZ, Zhang QL, Li FQ, Liu LX, Huo HL, and Huo JL
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- Amino Acid Sequence, Animals, Brain Stem metabolism, Cattle, Dogs, Esophagus metabolism, Horses, Humans, Isoelectric Point, Lymphotoxin beta Receptor genetics, Lymphotoxin beta Receptor metabolism, Male, Mice, Molecular Sequence Data, Molecular Weight, Organ Specificity, Pituitary Gland metabolism, Prostate metabolism, Protein Structure, Tertiary, Reverse Transcriptase Polymerase Chain Reaction, Sequence Homology, Amino Acid, Swine metabolism, Ursidae, Cloning, Molecular, Lymphotoxin beta Receptor chemistry, Open Reading Frames, Swine genetics
- Abstract
The lymphotoxin beta receptor (LTβR) is a member of the tumor necrosis factor family of receptors (TNFR). It plays a role in regulating lymphoid organogenesis and homeostasis of the immune system. In the present study, the full coding region of a putative LTβR gene of Sus scrofa was amplified by reverse transcription-polymerase chain reaction (RT-PCR) and cloned for the first time (accession Nos. JX457347 and AFU74012). In addition, analysis of the tissue expression profile was carried out via RT-PCR. The full-length coding region of porcine LTβR had 1266 nucleotides (molecular weight, 45.61 kDa; pI, 5.71) and encoded 421 amino acids. Bioinformatic prediction indicates that LTβR belongs to the TNFR superfamily and contains a TNFR domain. The sequence homology analysis revealed that the amino acid sequences of S. scrofa LTβR had 82.9, 82.4, 81.3, 80.5, 78.7, 74.6, and 73.0% identity with those of Equus caballus, Canis lupus, Ailuropoda melanoleuca, Oryctolagus cuniculus, Bos taurus, Mus musculus, and Homo sapiens, respectively. The phylogenetic tree based on the amino acid sequences of LTβR from 8 species revealed that S. scrofa was more closely related to E. caballus, C. lupus, and A. melanoleuca. RT-PCR analysis showed that the porcine LTβR gene was differentially expressed (e.g., high, moderate, low, or nonexistent) in various tissues (e.g., prostate, pituitary, brainstem, and esophagus, respectively). This may be related to differences in the regulation of LTβR in the different tissues.
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- 2014
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215. Morphology and structure characterization of bacterial celluloses produced by different strains in agitated culture.
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Bi JC, Liu SX, Li CF, Li J, Liu LX, Deng J, and Yang YC
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- Acetobacteraceae metabolism, Cellulose metabolism, Fermentation, Gluconacetobacter metabolism, Gluconacetobacter xylinus metabolism, Spectroscopy, Fourier Transform Infrared, X-Ray Diffraction, Acetobacteraceae chemistry, Cellulose chemistry, Cellulose ultrastructure, Gluconacetobacter xylinus chemistry
- Abstract
Aims: The influence of bacterial species/strains in agitated culture was investigated on the morphology and structure characteristics of bacterial cellulose., Methods and Results: Komagataeibacter nataicola Y19 and Gluconacetobacter entanii ACCC10215 were inoculated in Hestrin-Schramm (HS) medium and subjected to agitated cultivation. Different kinds of BCs were obtained including flocky asterisk-like BC by G. entanii ACCC10215 and solid sphere-like BC by K. nataicola Y19. The SEM results showed that the asterisk-like BC had larger pores than the solid sphere-like BC. The FT-IR and X-ray diffraction results showed the asterisk-like BC had lower crystallinity (81·43%), higher cellulose Iα mass fraction (79·74%) and smaller crystallite size., Conclusions: The different species/strains can influence the morphology and structure characteristics of BC in agitated culture., Significance and Impact of the Study: We examined the influence of different species/strains on the morphology, macro- and microstructure of BCs produced in agitated culture for the first time, which suggest that different BCs with potential applications could be obtained by choosing different species or strains and fermentation method., (© 2014 The Society for Applied Microbiology.)
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- 2014
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216. Genetic diversity of local Yunnan chicken breeds and their relationships with Red Junglefowl.
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Huo JL, Wu GS, Chen T, Huo HL, Yuan F, Liu LX, Ge CR, and Miao YW
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- Alleles, Animals, China, Meat, Phylogeny, Polymorphism, Genetic, Breeding, Chickens genetics, Genetic Variation, Microsatellite Repeats genetics
- Abstract
Yunnan is situated in the Southwest China and encompasses regions having high biodiversity, including habitats for several ancestral species of domestic animals such as chicken. Domestic chickens in Yunnan were kept by peoples of varied ethnic and economic backgrounds living in highly varied geographic environments. To identify the genetic background of Yunnan domestic chickens and their relationships with Red Junglefowl, we applied 28 widely used microsatellite DNA markers to genotype 340 birds from 7 chicken breeds and Red Junglefowl indigenous to Yunnan. Among a total of 342 alleles identified, 121 (35.4%) were breed specific, with Red Junglefowl harboring most microsatellite alleles (23). High levels of heterozygosity were observed within populations indicated by a mean unbiased HE value of 0.663, which was higher than the reported for most populations elsewhere. The FIS value of domestic populations ranged from -0.098-0.005, indicating a lack of inbreeding among these populations. A high proportion of significant departures (89) from the 224 HWE tests for each locus in each population reflected an excess of heterozygosity and population substructure. Individual assignment tests, high FST values (0.1757-0.3015), and Nei's DA genetic distances (0.4232-0.6950) indicated clear differentiation among these populations. These observations, along with the close genetic distance between indigenous domestic populations and Red Junglefowl, were consistent with the primitive and ancestral state of Yunnan indigenous chickens. Protecting the unique variants of these indigenous poultry varieties from contamination with commercial breeds might provide values for improving modern agricultural livestock and breeding programs. Thus, the current study may benefit breeding management and conservation efforts.
- Published
- 2014
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217. Liver abscesses in adult patients with and without diabetes mellitus: an analysis of the clinical characteristics, features of the causative pathogens, outcomes and predictors of fatality: a report based on a large population, retrospective study in China.
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Tian LT, Yao K, Zhang XY, Zhang ZD, Liang YJ, Yin DL, Lee L, Jiang HC, and Liu LX
- Subjects
- Adult, Aged, China, Drug Resistance, Bacterial, Escherichia coli isolation & purification, Female, Humans, Klebsiella pneumoniae isolation & purification, Liver Abscess, Pyogenic microbiology, Liver Abscess, Pyogenic therapy, Logistic Models, Male, Middle Aged, Odds Ratio, Prevalence, Retrospective Studies, Treatment Outcome, Diabetes Mellitus microbiology, Liver Abscess, Pyogenic complications
- Abstract
In China, there are four types of liver abscesses (LAs) that meet the clinical criteria. Pyogenic liver abscesses (PLAs) and amoebic liver abscesses (ALAs) are two of the most common types of abscesses, followed by fungal liver abscesses (FLAs) and hydatid secondary liver abscesses (HsLAs). Diabetes mellitus (DM) is associated with the development of PLAs. However, there is a lack of population-based studies that have evaluated the underlying relationship between LAs (mainly PLAs and FLAs) and DM. We conducted a retrospective study based on a large population to identify the potential differences and factors that affect the mortality of PLA patients in DM and non-DM groups. Our results revealed that the prevalence of DM is 44.3% (158/357) in PLA patients and 35.3% (18/51) in FLA patients. Compared with the non-DM patients, statistically significant differences were found in DM patients according to symptomatology, clinical manifestations, laboratory findings, microbiological characteristics, antimicrobial resistance, clinical treatments and outcomes in relation to mortality. In addition, the status of antibiotic resistance to E. coli and K. pneumoniae, which were isolated from the patient samples, is severe in the area in which the study was conducted. Regarding the treatment of PLAs, our study indicated that broad-spectrum antimicrobial therapy and drug combinations should be recommended and initiated before the pathogens are cultured and identified. In the clinic, therapies that combine percutaneous drainage with antibiotics and surgery with antibiotics are the two most useful strategies for treating an LA. These two combined treatments resulted in satisfactory cure rates. In the DM and non-DM groups, the cure rates for percutaneous drainage with antibiotics were 90.3% and 92.0%, respectively, and the cure rates for surgery with antibiotics were 93.9% and 95.2%, respectively., (© 2012 Lianxin Liu. © 2012 European Society of Clinical Microbiology and Infectious Diseases.)
- Published
- 2012
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218. Synthesis of one-dimensional TiO2/V2O5 branched heterostructures and their visible light photocatalytic activity towards Rhodamine B.
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Wang Y, Su YR, Qiao L, Liu LX, Su Q, Zhu CQ, and Liu XQ
- Abstract
We present the synthesis and visible-light-induced catalytic activity of one-dimensional (1D) TiO(2)/V(2)O(5) branched heterostructures. The 1D TiO(2)/V(2)O(5) heterostructures were prepared by RF reactive magnetron sputtering of V(2)O(5) onto electrospun TiO(2) nanofibers. Then, the samples were annealed at 300 °C for 2 h in air ambient to form the 1D TiO(2)/V(2)O(5) branched heterostructures. The photodecomposition rate of Rhodamine B (RhB) by the 1D TiO(2)/V(2)O(5) branched heterostructures under visible light was much faster than that of pure TiO(2) nanofibers, revealing that the visible-light-induced catalytic activity of the 1D TiO(2)/V(2)O(5) branched heterostructures was greatly improved. The enhancement of the photocatalytic activity of the 1D TiO(2)/V(2)O(5) branched heterostructures can be ascribed to the coupling with a small bandgap semiconductor material V(2)O(5), where the absorption range is extended, the photogenerated electrons and holes are highly separated and the surface charge carrier transfer rate is promoted.
- Published
- 2011
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219. Direct mass measurements of short-lived A=2Z-1 nuclides (63)Ge, (65)As, (67)Se, and (71)Kr and their impact on nucleosynthesis in the rp process.
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Tu XL, Xu HS, Wang M, Zhang YH, Litvinov YA, Sun Y, Schatz H, Zhou XH, Yuan YJ, Xia JW, Audi G, Blaum K, Du CM, Geng P, Hu ZG, Huang WX, Jin SL, Liu LX, Liu Y, Ma X, Mao RS, Mei B, Shuai P, Sun ZY, Suzuki H, Tang SW, Wang JS, Wang ST, Xiao GQ, Xu X, Yamaguchi T, Yamaguchi Y, Yan XL, Yang JC, Ye RP, Zang YD, Zhao HW, Zhao TC, Zhang XY, and Zhan WL
- Abstract
Mass excesses of short-lived A=2Z-1 nuclei (63)Ge, (65)As, (67)Se, and (71)Kr have been directly measured to be -46,921(37), -46,937(85), -46,580(67), and -46,320(141) keV, respectively. The deduced proton separation energy of -90(85) keV for (65)As shows that this nucleus is only slightly proton unbound. X-ray burst model calculations with the new mass excess of (65)As suggest that the majority of the reaction flow passes through (64)Ge via proton capture, indicating that (64)Ge is not a significant rp-process waiting point.
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- 2011
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220. Therapeutic effect of photodynamic therapy using hematoporphyrin monomethyl ether (HMME) on human cholangiocarcinoma cell line QBC939.
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Wang JB, Liu LX, Pan SH, Wang CY, and Fu QF
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- Apoptosis drug effects, Bile Duct Neoplasms pathology, Caspase 3 metabolism, Cell Line, Tumor, Cholangiocarcinoma pathology, Cytochromes c metabolism, Humans, Bile Duct Neoplasms drug therapy, Bile Ducts, Intrahepatic, Cholangiocarcinoma drug therapy, Hematoporphyrins therapeutic use, Photochemotherapy
- Abstract
Unlabelled: Photodynamic therapy (PDT) is an effective local cancer treatment when aphotosensitizer is administered and the tumor is irradiated with light. We examined the effect of PDT using HMME as the photosensitizer, and the 630nm diode laser on human cholangiocarcinoma cell line QBC939. Cell viability was determined by MTT assay. The percentage of apoptotic cell was determined by flow cytometry following annexin V/PI staining. Two methods were used for the determination of apoptosis: terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling assay and laser scanning confocal microscope detection. The procaspase-3 and cytochrome cwere measured by western blot. In vitro PDT showed excellent cytotoxicity that was afunction of laser energy and drug concentration to the QBC939 cell lines. PDT-mediated cell death occurred predominantly by apoptosis in vitro. Furthermore, this treatment initiates early cytochrome crelease, followed by late procaspase-3 activation. Our study demonstrates that PDT using HMME and the diode laser induces apoptosis that is mediated by cytochrome crelease and caspase activation in human cholangiocarcinoma cell lines. It is expected that this therapy would be clinically useful for the treatment of patients with cholangiocarcinoma., Keywords: Hematoporphyrin monomethyl ether, photodynamic therapy, apoptosis, cholangiocarcinoma.
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- 2010
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221. Variation of human papillomavirus 16 in cervical and lung cancers in Sichuan, China.
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Zhang J, Wang T, Han M, Yang ZH, Liu LX, Chen Y, Zhang L, Hu HZ, and Xi MR
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- Adult, Aged, Base Sequence, China epidemiology, Female, Human papillomavirus 16 classification, Human papillomavirus 16 isolation & purification, Humans, Lung Neoplasms epidemiology, Male, Middle Aged, Molecular Sequence Data, Oncogene Proteins, Viral genetics, Papillomavirus Infections epidemiology, Uterine Cervical Neoplasms epidemiology, Young Adult, Genetic Variation, Human papillomavirus 16 genetics, Lung Neoplasms virology, Papillomavirus Infections virology, Uterine Cervical Neoplasms virology
- Abstract
Although the crucial role of human papillomaviruses (HPVs), especially HPV-16 in various cancers has been confirmed, the variation of HPV-16 among different cancers have not been investigated in a specific geographic location. In order to elucidate whether similar HPV-16 variants are involved in different kinds of cancers in the same geographic location, the analysis of sequence variants of E6 and E7 oncogenes and L1 gene of HPV-16 in cervical and lung cancers in Sichuan, China, was carried out. Tissue samples from 122 cervical cancers, 104 lung cancers, and 138 controls were subjected to RT-PCR or PCR, sequencing, and sequence analysis. The infection rates of HPV-16 in cervical, lung cancers, and non-malignant controls were 68.9%, 17.3%, and 37.0%, respectively. Asian prototype variants prevailed in cervical and lung cancers, while European prototype variants in non-malignant controls. In comparison to the lung cancer, cervical cancer showed a much higher diversity of HPV-16 oncogenes. These results indicate that in Sichuan, China, Asian prototype variants of HPV-16 are more pathogenic than their European counterparts.
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- 2010
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222. Effects of alkylated-chitosan-DNA nanoparticles on the function of macrophages.
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Liu LX, Song CN, Song LP, Zhang HL, Dong X, and Leng XG
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- Alkylation, Animals, Biocompatible Materials, Cell Line, Cytokines biosynthesis, Enzyme-Linked Immunosorbent Assay, Inflammation Mediators metabolism, Macrophages cytology, Mice, Phagocytosis, Chitosan chemistry, DNA chemistry, Macrophages metabolism, Nanoparticles
- Abstract
Chitosan could form nanoparticles with DNA through electrostatic interaction, and hence protect the DNA from enzymatic degradation. Numerous studies have been working on modifying chitosan aiming at improving its transgenic efficacy. While the modification of chitosan with alkyl group has been shown to significantly improve the cell transfection efficiency, little is known about its impact on its biocompatibility. The current study was performed to investigate the impact of alkylated-chitosan/DNA nanoparticles on the function of the murine macrophage through observing its phagocytic activity and production of pro-inflammatory cytokines (IL-1beta, IL-6, IL-10, IL-12 and TNF-alpha). Our results demonstrated that the alkylated-chitosan/DNA nanoparticles at the concentration of 20 microg/ml DNA content had no significant impact on the production of cytokines and phagocytic activity of the macrophages as compared with the unmodified chitosan/DNA nanoparticles and negative control even after 24 h co-incubation. It suggested that the modification of chitosan with alkyl group should not have negative impact on the function of the macrophages.
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- 2009
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223. Comparative study of different treatments for malignant tracheoesophageal/bronchoesophageal fistulae.
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Hu Y, Zhao YF, Chen LQ, Zhu ZJ, Liu LX, Wang Y, and Kou YL
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- Bronchial Fistula etiology, Bronchial Fistula mortality, Carcinoma, Squamous Cell complications, Cause of Death, Esophageal Fistula etiology, Esophageal Fistula mortality, Esophageal Neoplasms complications, Female, Humans, Kaplan-Meier Estimate, Male, Middle Aged, Prosthesis Design, Stents, Surveys and Questionnaires, Tracheoesophageal Fistula etiology, Tracheoesophageal Fistula mortality, Bronchial Fistula therapy, Esophageal Fistula therapy, Gastrostomy, Quality of Life, Tracheoesophageal Fistula therapy
- Abstract
The aim of this study is to compare the survival time and quality of life (QOL) of patients who have received different treatment for tracheoesophageal/bronchoesophageal fistula. Between January 2003 and December 2007, 35 patients with malignant tracheoesophageal/bronchoesophageal fistula were recorded as the control group, gastrostomy group, and stenting group, respectively, according to the treatments they chose. Two weeks after the treatment, European Organization for Research and Treatment of Cancer Quality of Life Core 30 Questionnaire (QLQ-C30), Quality of Life Questionnaire-esophageal module (QLQ-OES18), and a respiratory symptom-related QOL index are employed to assess QOL of these patients. There is no significant difference in survival time and constituent ratio of death reason among groups. Except for eight patients who died within 2 weeks after the treatment, all other 27 patients returned back the questionnaires. As compared to the control group, patients in the gastrostomy group gained a low score in emotional function and financial situation, while patients in the stenting group had lower scores in financial problems and seven respiratory and eating-related symptoms. In contrast with the gastrostomy group, patients in stenting group had higher scores in emotional and social functions, and lower scores in six respiratory and eating-related symptoms. With patients' QOL considered, the self-expandable coated stenting should be the first choice of therapy for malignant tracheoesophageal/bronchoesophageal fistula, whereas gastrostomy should be kept from use.
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- 2009
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224. Effect of particle properties on the flowability of ibuprofen powders.
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Liu LX, Marziano I, Bentham AC, Litster JD, White ET, and Howes T
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- Lubricants chemistry, Microscopy, Electron, Scanning, Models, Theoretical, Particle Size, Powders, Stearic Acids chemistry, Surface Properties, Ibuprofen chemistry, Technology, Pharmaceutical methods
- Abstract
Powder flowability is one of the key parameters in the pharmaceutical tabletting process. The flowability is affected by both the particles' properties and the tabletting equipment characteristics. Although it is generally accepted that powder flowability increases with an increase in particle size, quantitative studies and comprehensive theoretical insights into the particle property effects are still lacking. In this paper, ibuprofen, a non-steroidal drug widely used as an anti-inflammatory analgesic was chosen as a model material to assess the effect of particle properties on its flowability. Ibuprofen typically has a needle shaped morphology. The flowability of ibuprofen size fractions was studied in detail using two flow measurement methods. The separated fractions were also compared to magnesium stearate lubricated ibuprofen and its size fractions. The experimental results showed that powder flowability is significantly affected by both the particle size and size distribution. The finest size fraction that is separated from the bulk ibuprofen powder flows better than the bulk powder. For powders with narrow size distributions, the flowability increases significantly with the increase in particle size. In addition, admixing magnesium stearate to ibuprofen not only increases the flow function of the powder, but also reduces the internal friction angle. A theoretical analysis based on the limiting tensile strength of the powder bed was carried out and the flow conditions for particles of different size and shape were developed.
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- 2008
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225. Isolation and characterization of polymorphic microsatellite loci from RAPD product in half-smooth tongue sole (Cynoglossus semilaevis) and a test of cross-species amplification.
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Liu YG, Bao BL, Liu LX, Wang L, and Lin H
- Abstract
Eleven polymorphic microsatellite loci have been isolated and characterized from random amplified polymorphic DNA product in half-smooth tongue sole, Cynoglossus semilaevis. Twenty-one microsatellites were selected for designing microsatellite primers, of which 11 gave working primer pairs. They had between three and 12 alleles. Observed and expected heterozygosities varied from 0.53 to 0.93, and from 0.52 to 0.80, respectively. Five additional fish species assessed for cross-species amplification revealed between one and three positive amplifications and between zero and three polymorphic loci per species., (© 2007 The Authors.)
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- 2008
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226. Endosperm-specific hypomethylation, and meiotic inheritance and variation of DNA methylation level and pattern in sorghum (Sorghum bicolor L.) inter-strain hybrids.
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Zhang MS, Yan HY, Zhao N, Lin XY, Pang JS, Xu KZ, Liu LX, and Liu B
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- Azacitidine pharmacology, Hybridization, Genetic, Inheritance Patterns, Meiosis genetics, Plant Leaves drug effects, Plant Leaves genetics, Plant Leaves metabolism, RNA metabolism, Sorghum embryology, Sorghum metabolism, Stochastic Processes, DNA Methylation, Epigenesis, Genetic, Seeds genetics, Sorghum genetics
- Abstract
Understanding dynamics and inheritance of DNA methylation represents important facets for elucidating epigenetic paradigms in plant development and evolution. Using four sets of sorghum (Sorghum bicolor L.) inter-strain hybrids and their inbred parents, the developmental stability and inheritance of cytosine methylation in two tissues, leaf and endosperm, by MSAP analysis were investigated. It was found that in all lines (inbred and hybrid) studied, endosperm exhibited a markedly reduced level of full methylation of the external cytosine or both cytosines at the CCGG sites relative to leaf, which caused a variable reduction in the estimated total methylation level in endosperm by 6.89-19.69% (11.47% on average). For both tissues, a great majority of cytosine methylation profiles transmitted to F1 hybrids, however, from 1.69 to 3.22% of the profiles showed altered patterns in hybrids. Both inherited and altered methylation profiles can be divided into distinct groups, and their frequencies are variable among the cross-combinations, and between the two tissues. The variations in methylation level and pattern detected in the hybrids were not caused by parental heterozygosity, and they could be either non-random or stochastic among hybrid individuals. Homology analysis of isolated bands that showed endosperm-specific hypomethylation or variation in hybrids indicated that diverse sequences were involved, including known-function cellular genes and mobile elements. RT-PCR analysis of six genes representing endosperm-specific hypomethylation in MSAP profiles indicated that all showed higher expression in endosperm than in leaf, suggesting involvement of methylation state in regulating tissue-specific or tissue-biased expression in sorghum. Analysis on leaf-RNA from 5-azacytidine-treated plants further corroborated this possibility.
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- 2007
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227. The role of noninvasive monitoring of cerebral electrical impedance in stroke.
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Liu LX, Dong WW, Wang J, Wu Q, He W, and Jia YJ
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- Cerebral Hemorrhage complications, Female, Humans, Male, Monitoring, Physiologic methods, Reproducibility of Results, Sensitivity and Specificity, Stroke etiology, Brain physiopathology, Cerebral Hemorrhage diagnosis, Cerebral Hemorrhage physiopathology, Electric Impedance, Plethysmography, Impedance methods, Stroke diagnosis, Stroke physiopathology
- Abstract
Objective: To explore the change regularity of cerebral electrical impedance (CEI) in the healthy people and patients with intracerebral hemorrhage (ICH) and ischemic stroke., Methods: CEI of 100 healthy volunteers, 52 patients with ICH and 33 patients with ischemic stroke was measured by noninvasive Brain-Edema Monitor. The results of perturbative index (PI) converted from CEI were compared with the volume of infarction, hematoma and surrounding edema, which calculated by image analyzing system according to MRI or CT., Results: In the normal groups, PI in the left and right sides of cerebral hemispheres was respectively 7.76 +/- 0.75 and 7.79 +/- 0.58, and there was no significant difference between the two sides (P > 0.05). In the patients with ICH, PI in the hematoma side decreased and was lower than the other side, and then increased gradually, finally exceeded that of the other side. The average "cross" time was (16.25 +/- 8.96) h. It showed that the volume of hematoma was no obvious change before and after the "cross" time [(31.25 +/- 21.59) vs (37.59 +/- 27.57)] (P > 0.05). However, the volume of peri-hematoma edema was significantly larger after the "cross" time than before the "cross" time [(26.35 +/- 13.96) vs (14.68 +/- 5.30)] (P < 0.05). There was a positive correlation between the PI of hematoma side and the volume of peri-hematoma edema (r = 0.8811, P < 0.01). In the patients with arterothrombotic cerebral infarction, PI in the infarct side had a positive correlation with the volume of infarction (r = 0.8496, P < 0.01)., Conclusions: CEI is a stable physical parameter reflecting the electrical character of human brain tissue. It is useful for monitoring edema and hematoma in stroke.
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- 2005
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228. A reverse genetic analysis of components of the Toll signaling pathway in Caenorhabditis elegans.
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Pujol N, Link EM, Liu LX, Kurz CL, Alloing G, Tan MW, Ray KP, Solari R, Johnson CD, and Ewbank JJ
- Subjects
- Actinomycetales pathogenicity, Amino Acid Sequence, Animals, Ascomycota pathogenicity, Base Sequence, Caenorhabditis elegans microbiology, Conserved Sequence, DNA-Binding Proteins, Genes, Helminth, Genes, Lethal, Helminth Proteins genetics, Immunity, Innate, Mitosporic Fungi pathogenicity, Molecular Sequence Data, Nerve Tissue Proteins genetics, Phosphoproteins, Protein Serine-Threonine Kinases, Pseudomonas aeruginosa pathogenicity, Sequence Homology, Amino Acid, Signal Transduction, Behavior, Animal physiology, Caenorhabditis elegans physiology, Caenorhabditis elegans Proteins, Drosophila Proteins, Helminth Proteins metabolism, Nerve Tissue Proteins metabolism
- Abstract
Background: Both animals and plants respond rapidly to pathogens by inducing the expression of defense-related genes. Whether such an inducible system of innate immunity is present in the model nematode Caenorhabditis elegans is currently an open question. Among conserved signaling pathways important for innate immunity, the Toll pathway is the best characterized. In Drosophila, this pathway also has an essential developmental role. C. elegans possesses structural homologs of components of this pathway, and this observation raises the possibility that a Toll pathway might also function in nematodes to trigger defense mechanisms or to control development., Results: We have generated and characterized deletion mutants for four genes supposed to function in a nematode Toll signaling pathway. These genes are tol-1, trf-1, pik-1, and ikb-1 and are homologous to the Drosophila melanogaster Toll, dTraf, pelle, and cactus genes, respectively. Of these four genes, only tol-1 is required for nematode development. None of them are important for the resistance of C. elegans to a number of pathogens. On the other hand, C. elegans is capable of distinguishing different bacterial species and has a tendency to avoid certain pathogens, including Serratia marcescens. The tol-1 mutants are defective in their avoidance of pathogenic S. marcescens, although other chemosensory behaviors are wild type., Conclusions: In C. elegans, tol-1 is important for development and pathogen recognition, as is Toll in Drosophila, but remarkably for the latter rôle, it functions in the context of a behavioral mechanism that keeps worms away from potential danger.
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- 2001
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229. Vancomycin resistance reversal in enterococci by flavonoids.
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Liu LX, Durham DG, and Richards RM
- Subjects
- Colony Count, Microbial, Drug Interactions, Enterococcus faecalis pathogenicity, Enterococcus faecium pathogenicity, Microbial Sensitivity Tests, Anti-Bacterial Agents pharmacology, Enterococcus faecalis drug effects, Enterococcus faecium drug effects, Flavonoids pharmacology, Mutagens pharmacology, Vancomycin pharmacology, Vancomycin Resistance
- Abstract
The development of clinical vancomycin-resistant strains of enterococci (VRE) is a major cause for concern. Here we show that a combination of galangin or 3,7-dihydroxyflavone with vancomycin may be used to sensitize resistant strains of Enterococcus faecalis and Enterococcus faecium to the level of vancomycin-sensitive strains. Minimum inhibitory concentrations (MICs) and viable counts were determined in Iso-sensitest broth using a microtitre method. MICs of vancomycin against 67% of resistant clinical isolates and a type strain of enterococci were lowered from > 250 microg mL(-1) to < 4 microg mL(-1) in the presence of galangin (12.5 microg mL(-1)) or 3,7-dihydroxyflavone (6.25 microg mL(-1)). Viable counts for type culture E. faecalis ATCC 51299 showed the flavonoids alone significantly lowered numbers of colony forming units (CFUs). CFUs were maintained at low levels (< 10(3) CFU mL(-1)) for 24 h by vancomycin/flavone combinations. This combinational action in reversing vancomycin resistance of enterococci highlights novel drug targets and has importance in the design of new therapeutic regimes against resistant pathogens.
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- 2001
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230. Mutation of a conserved residue (D123) required for oligomerization of human immunodeficiency virus type 1 Nef protein abolishes interaction with human thioesterase and results in impairment of Nef biological functions.
- Author
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Liu LX, Heveker N, Fackler OT, Arold S, Le Gall S, Janvier K, Peterlin BM, Dumas C, Schwartz O, Benichou S, and Benarous R
- Subjects
- Amino Acid Sequence, Cell Membrane immunology, Dimerization, Gene Products, nef chemistry, Gene Products, nef genetics, HIV-1 physiology, HeLa Cells, Humans, Molecular Sequence Data, Mutagenesis, Site-Directed, Oligopeptides chemistry, Oligopeptides genetics, Oligopeptides immunology, Palmitoyl-CoA Hydrolase, Protein Binding, Protein Conformation, nef Gene Products, Human Immunodeficiency Virus, CD4 Antigens biosynthesis, Conserved Sequence, Down-Regulation immunology, Gene Products, nef immunology, HIV-1 immunology, HLA-A2 Antigen biosynthesis, Thiolester Hydrolases immunology
- Abstract
Nef is a myristoylated protein of 27 to 35 kDa that is conserved in primate lentiviruses. In vivo, Nef is required for high viral load and full pathological effects. In vitro, Nef has at least four activities: induction of CD4 and major histocompatibility complex (MHC) class I downregulation, enhancement of viral infectivity, and alteration of T-cell activation pathways. We previously reported that the Nef protein from human immunodeficiency virus type 1 interacts with a novel human thioesterase (hTE). In the present study, by mutational analysis, we identified a region of the Nef core, extending from the residues D108 to W124, that is involved both in Nef-hTE interaction and in Nef-induced CD4 downregulation. This region of Nef is located on the oligomer interface and is in close proximity to the putative CD4 binding site. One of the mutants carrying a mutation in this region, targeted to the conserved residue D123, was also found to be defective in two other functions of Nef, MHC class I downmodulation and enhancement of viral infectivity. Furthermore, mutation of this residue affected the ability of Nef to form dimers, suggesting that the oligomerization of Nef may be critical for its multiple functions.
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- 2000
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231. Therapeutic target discovery using Caenorhabditis elegans.
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Link EM, Hardiman G, Sluder AE, Johnson CD, and Liu LX
- Subjects
- Animals, Humans, Mutation genetics, Mutation physiology, Phenotype, Caenorhabditis elegans drug effects, Caenorhabditis elegans genetics, Pharmacogenetics methods
- Abstract
Use of the human genome sequence in disease therapy will require efficient identification of disease-causing and disease-associated genes with functions that are amenable to pharmacological manipulation. The validation and development of such genes as therapeutic targets requires information about both the genes' functions and the biochemical pathways in which they participate. One powerful means of obtaining such information is the study of homologous genes in model organisms amenable to laboratory manipulation. Among model organisms the nematode Caenorhabditis elegans offers several advantages, including well-established techniques for genetic and experimental manipulation and the first completed genome sequence for a multicellular organism. Molecular genetic experiments using C. elegans can contribute at several levels to drug discovery programs, from elucidation of genetic functions and pathways to the validation of candidate targets. Additionally, the ease of culture allows adaptation of the nematode for use in high-throughput chemical screens for the identification of lead compounds in drug development.
- Published
- 2000
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232. Novel antimicrobial targets from combined pathogen and host genetics.
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Johnson CD and Liu LX
- Subjects
- Animals, Anti-Bacterial Agents chemistry, Anti-Bacterial Agents therapeutic use, Bacteria genetics, Caenorhabditis elegans genetics, Caenorhabditis elegans microbiology, Gene Expression Regulation drug effects, Genes, Bacterial, Genes, Helminth, Helminth Proteins genetics, Humans, Hypoxia-Inducible Factor-Proline Dioxygenases, Immediate-Early Proteins genetics, Immunity, Innate, Mammals genetics, Procollagen-Proline Dioxygenase, Pseudomonas Infections drug therapy, Pseudomonas aeruginosa genetics, Rats, Virulence genetics, Anti-Bacterial Agents pharmacology, Caenorhabditis elegans Proteins, DNA-Binding Proteins, Drug Design
- Published
- 2000
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233. Regulation of the insulin-like developmental pathway of Caenorhabditis elegans by a homolog of the PTEN tumor suppressor gene.
- Author
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Gil EB, Malone Link E, Liu LX, Johnson CD, and Lees JA
- Subjects
- Alleles, Amino Acid Sequence, Animals, Caenorhabditis elegans metabolism, Caenorhabditis elegans Proteins, Humans, Insulin-Like Growth Factor I metabolism, Molecular Sequence Data, Mutation, PTEN Phosphohydrolase, Phosphatidylinositol 3-Kinases genetics, Phosphatidylinositol 3-Kinases metabolism, Receptor, Insulin genetics, Receptor, Insulin metabolism, Sequence Homology, Nucleic Acid, Caenorhabditis elegans genetics, Gene Expression Regulation, Genes, Tumor Suppressor, Insulin-Like Growth Factor I genetics, Phosphoric Monoester Hydrolases genetics, Signal Transduction genetics, Tumor Suppressor Proteins
- Abstract
The human PTEN tumor suppressor gene is mutated in a wide variety of sporadic tumors. To determine the function of PTEN in vivo we have studied a PTEN homolog in Caenorhabditis elegans. We have generated a strong loss-of-function allele of the PTEN homolog and shown that the deficient strain is unable to enter dauer diapause. An insulin-like phosphatidylinositol 3-OH kinase (PI3'K) signaling pathway regulates dauer-stage entry. Mutations in either the daf-2 insulin receptor-like (IRL) gene or the age-1 encoded PI3'K catalytic subunit homolog cause constitutive dauer formation and also affect the life span, brood size, and metabolism of nondauer animals. Strikingly, loss-of-function mutations in the age-1 PI3'K and daf-2 IRL genes are suppressed by loss-of-function mutations in the PTEN homolog. We establish that the PTEN homolog is encoded by daf-18, a previously uncloned gene that has been shown to interact genetically with the DAF-2 IRL AGE-1 PI3'K signaling pathway. This interaction provides clear genetic evidence that PTEN acts to antagonize PI3'K function in vivo. Given the conservation of the PI3'K signaling pathway between C. elegans and mammals, the analysis of daf-18 PTEN mutant nematodes should shed light on the role of human PTEN in the etiology of metabolic disease, aging, and cancer.
- Published
- 1999
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234. D2S, D2L, D3, and D4 dopamine receptors couple to a voltage-dependent potassium current in N18TG2 x mesencephalon hybrid cell (MES-23.5) via distinct G proteins.
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Liu LX, Burgess LH, Gonzalez AM, Sibley DR, and Chiodo LA
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- Animals, Autoreceptors drug effects, Autoreceptors physiology, Cell Line, Transformed, Cricetinae, GTP-Binding Proteins physiology, Membrane Potentials drug effects, Mesencephalon drug effects, Mesencephalon physiology, Patch-Clamp Techniques, Potassium Channels physiology, Rats, Receptors, Dopamine physiology, Dopamine Agonists pharmacology, GTP-Binding Proteins drug effects, Potassium Channels drug effects, Receptors, Dopamine drug effects
- Abstract
We utilized the approach of stably expressing different dopamine (DA) receptors into identified cell lines in an attempt to better understand the coupling of these receptors to membrane ion channels via second messenger systems. Recently, we examined the N18TG2 x mesencephalon (MES-23.5) cell line that is phenotypically similar to mesencephalic dopamine-containing neurons. Whole-cell voltage-clamp methods were used to investigate a voltage-dependent K+ current present in these cells. Untransfected MES-23.5 cells displayed a voltage-dependent slow-onset, slowly inactivating outward current which was not altered by bath application of either the D2 DA receptor agonist quinpirole (QUIN; 10-100 microM) or the D1 DA receptor agonist SKF38393, indicating that these cells were devoid of DA receptors. The K+ current studied was activated upon depolarization from a holding potential of -60 mV to a level more positive than -20 mV and was observed to be sensitive to bath application of tetraethylammonium. When MES-23.5 cells were transfected to stably express the D2S, D2L, D3, and D4 receptors, the same current was observed. In cells expressing D2L, D2S, and D3 receptors, application of the DA receptor agonists QUIN (1-80 microM), 7-hydroxy-dipropylaminoteralin (7-OH-DPAT, 1-80 microM), and dopamine (DA, 1-80 microM), increased the peak outward current by 35-40%. In marked contrast, cells stably expressing the D4 receptor demonstrated a significant DA agonist-induced reduction of the peak K+ current by 40%. For all four receptor subtypes, the D2-like receptor antagonist sulpiride (SUL 5 microM), when coapplied with QUIN (10 microM), totally abolished the change in K+ current normally observed, while coapplication of the D1-like receptor antagonist SCH23390 was without effect. The modulation of K+ current by D2L, D3, and D4 receptor stimulation was prevented by pretreatment of the cells with pertussis toxin (PTX, 500 ng/ml for 4 h). In addition, the intracellular application of a polyclonal antibody which specifically recognizes Goalpha completely blocked the ability of D2L, D3, and D4 receptors to modulate outward K+ currents. In contrast, the intracellular application of an antibody directed against Goalpha was without effect, whereas intracellular application of an antibody recognizing Gsalpha abolished the ability of the D2S receptor to enhance K+ current. These findings demonstrate that different members of the D2 DA receptor family may couple in a given cell to a common effector in dramatically different ways.
- Published
- 1999
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235. A molecular evolutionary framework for the phylum Nematoda.
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Blaxter ML, De Ley P, Garey JR, Liu LX, Scheldeman P, Vierstraete A, Vanfleteren JR, Mackey LY, Dorris M, Frisse LM, Vida JT, and Thomas WK
- Subjects
- Animals, Caenorhabditis elegans classification, Caenorhabditis elegans genetics, DNA, Helminth, DNA, Ribosomal, Molecular Sequence Data, Nematoda genetics, Parasites classification, Phylogeny, Evolution, Molecular, Nematoda classification
- Abstract
Nematodes are important: parasitic nematodes threaten the health of plants, animals and humans on a global scale; interstitial nematodes pervade sediment and soil ecosystems in overwhelming numbers; and Caenorhabditis elegans is a favourite experimental model system. A lack of clearly homologous characters and the absence of an informative fossil record have prevented us from deriving a consistent evolutionary framework for the phylum. Here we present a phylogenetic analysis, using 53 small subunit ribosomal DNA sequences from a wide range of nematodes. With this analysis, we can compare animal-parasitic, plant-parasitic and free-living taxa using a common measurement. Our results indicate that convergent morphological evolution may be extensive and that present higher-level classification of the Nematoda will need revision. We identify five major clades within the phylum, all of which include parasitic species. We suggest that animal parasitism arose independently at least four times, and plant parasitism three times. We clarify the relationship of C. elegans to major parasitic groups; this will allow more effective exploitation of our genetic and biological knowledge of this model species.
- Published
- 1998
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236. GPIIIa-(49-66) is a major pathophysiologically relevant antigenic determinant for anti-platelet GPIIIa of HIV-1-related immunologic thrombocytopenia.
- Author
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Nardi MA, Liu LX, and Karpatkin S
- Subjects
- Animals, Epitope Mapping, Female, HIV Infections blood, HIV Infections physiopathology, Humans, Integrin beta3, Male, Mice, Thrombocytopenia physiopathology, Antibodies blood, Antigens, CD immunology, Blood Platelets immunology, HIV Infections immunology, HIV-1, Immunodominant Epitopes immunology, Peptide Fragments immunology, Platelet Glycoprotein GPIIb-IIIa Complex, Platelet Membrane Glycoproteins immunology, Thrombocytopenia immunology
- Abstract
High-affinity (Kd = 1 x 10(-9) M) anti-platelet GPIIIa has been isolated from serum immune complexes of immunologic thrombocytopenic HIV-1-infected patients (HIV-1-ITP). Affinity-purified anti-platelet antibody reacted with a recombinant GPIIIa-(1-200) and -(1-66) fusion peptide and with an 18-mer GPIIIa-(49-66) peptide but not with seven other GPIIIa peptides spanning the length of GPIIIa. Most of the anti-platelet antibody ( approximately 85%) could be adsorbed to and eluted from a GPIIIa-(49-66) affinity column. Binding of antibody to platelets could be inhibited by GPIIIa-(49-66) or an equimolar peptide-albumin conjugate (IC50 = 2 microM). Sera from 7 control subjects and 10 classic autoimmune thrombocytopenic patients gave background reactivity with GPIIIa-(49-66). HIV-1-ITP sera from 16 patients reacted with a mean OD 6-fold greater than background (range, 4- to 9-fold). Serum anti-GPIIIa-(49-66) concentration correlated inversely with platelet count, R2 = 0.51, n = 31, P < 0. 0001. Because mouse platelet GPIIIa-(49-66) has 83% homology with human GPIIIa and mouse monocytes contain Fc receptors for the human IgG1-kappa/lambda antibody, we determined the in vivo effect of human anti-GPIIIa on mouse platelets. Affinity-purified antibody, 25-50 microg given i.p., resulted in a precipitous drop in platelet count to 30% of baseline, with nadir at 4 hr and return to normal in 36 hr. No effect was noted with control IgG. Acute thrombocytopenia could be prevented or reversed by the injection of the GPIIIa-(49-66) albumin conjugate at zero time or 2 hr after antibody, respectively, but not with a scrambled peptide-albumin conjugate. Thus HIV-1-ITP patients have high-affinity anti-platelet GPIIIa against a major antigenic determinant, GPIIIa-(49-66), which correlates inversely with platelet count and induces thrombocytopenia in mice.
- Published
- 1997
- Full Text
- View/download PDF
237. Use of the two-hybrid system to identify cellular partners of the HIV1 Nef protein.
- Author
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Benichou S, Liu LX, Erdtmann L, Selig L, and Benarous R
- Subjects
- Animals, Coatomer Protein, Humans, Lymphocyte Specific Protein Tyrosine Kinase p56(lck), Protein Processing, Post-Translational, Protein-Tyrosine Kinases metabolism, Proto-Oncogene Proteins metabolism, Proto-Oncogene Proteins c-hck, Recombinant Proteins metabolism, nef Gene Products, Human Immunodeficiency Virus, src-Family Kinases metabolism, Gene Products, nef metabolism, HIV-1, Microtubule-Associated Proteins metabolism, Thiolester Hydrolases metabolism
- Published
- 1997
- Full Text
- View/download PDF
238. D2L, D2S, and D3 dopamine receptors stably transfected into NG108-15 cells couple to a voltage-dependent potassium current via distinct G protein mechanisms.
- Author
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Liu LX, Monsma FJ Jr, Sibley DR, and Chiodo LA
- Subjects
- Animals, Dose-Response Relationship, Drug, Rats, Transfection, GTP-Binding Proteins physiology, Membrane Potentials drug effects, Potassium Channels drug effects, Quinpirole pharmacology, Receptors, Dopamine drug effects, Receptors, Dopamine physiology
- Abstract
The D2-like dopamine (DA) receptor family has continued to expand and now includes the D2-short (D2S) and D2-long (D2L) receptor isoforms and the D3 and D4 receptors. The D2 receptor isoforms differ in length by 29 amino acids within the third cytoplasmic loop, a region of the receptor believed to be important for G protein coupling. This observation has led to the hypothesis that the two isoforms of the D2 receptor may utilize different signal transduction pathways when present in the same cell. The D2 and D3 receptors, although mostly different, show some common amino acid sequences within the third cytoplasmic loop. Thus, it is possible that the D2 and D3 receptors may employ similar signal transduction pathways. To test these hypotheses directly, NG108-15 neuroblastoma-glioma hybrid cells were stably transfected to express either the D2S, D2L, or D3 DA receptors. All transfected but not untransfected NG108-15 cells demonstrated a dose-dependent reduction in the peak whole-cell potassium (K+) current in response to receptor activation by DA or the DA receptor agonists quinpirole (QUIN) and apomorphine (APO). The modulation of K+ current by D2S receptor stimulation was prevented by pretreatment of the cells with cholera toxin (20 micrograms/ml for 18 h), whereas pertussis toxin pretreatment (500 ng/ml for 4 h) completely blocked the effects of D2L and D3 receptor activation. These observations suggest that the signal transduction mechanisms involved in coupling the two isoforms of the D2 receptor to the K+ current are different, whereas the D2L and D3 receptor coupling mechanisms may be similar. In direct support of this hypothesis, it was observed that the intracellular application of a polyclonal antibody that is specific for the GO alpha subunit completely blocked the ability of D2L and D3 receptors to modulate outward K+ currents. In contrast, the D2S-mediated modulation of K+ currents was blocked by intracellular application of an antibody recognizing GS alpha but not GO alpha. These findings demonstrate that D2S and D2L receptors are able to couple to a common effector in a cell via two G protein pathways.
- Published
- 1996
- Full Text
- View/download PDF
239. Interaction between the cytoplasmic domains of HIV-1 Vpu and CD4: role of Vpu residues involved in CD4 interaction and in vitro CD4 degradation.
- Author
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Margottin F, Benichou S, Durand H, Richard V, Liu LX, Gomas E, and Benarous R
- Subjects
- Amino Acid Sequence, CD4 Antigens physiology, Casein Kinase II, Human Immunodeficiency Virus Proteins, Molecular Sequence Data, Point Mutation, Protein Serine-Threonine Kinases genetics, Protein Serine-Threonine Kinases metabolism, Sequence Deletion, Viral Regulatory and Accessory Proteins physiology, Yeasts, CD4 Antigens genetics, CD4 Antigens metabolism, HIV-1 genetics, HIV-1 metabolism, Viral Regulatory and Accessory Proteins genetics, Viral Regulatory and Accessory Proteins metabolism
- Abstract
The Vpu and CD4 cytoplasmic domains were found, by using a two-hybrid assay in yeast, to interact in the absence of their membrane anchor domains. Studies on several deletion and point mutants revealed that the overall structure of the Vpu cytoplasmic domain is required for this interaction. The Vpu amino acid residues involved in the interaction with CD4 were identified. Deletion of the C-terminal residues of Vpu, required for CD4 degradation, as well as the double mutation on the casein kinase II phosphorylation sites S52N-S56N, also involved in CD4 degradation, resulted in the loss of interaction with CD4 and in the inability to induce CD4 degradation. These results suggest that the ability of Vpu to mediate the degradation of CD4 is linked to its capacity to physically interact with CD4. However, additional mutagenesis on the S52 site revealed that the interaction between the cytoplasmic domains of Vpu and CD4 is not sufficient for in vitro Vpu-mediated CD4 degradation.
- Published
- 1996
- Full Text
- View/download PDF
240. [A novel conservative structure found in the carp mitochondrial tRNA(phe) gene].
- Author
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Mi ZY, Liu LX, Wang GF, and Wu NH
- Subjects
- Animals, Base Sequence, Cattle, Chickens, Humans, Mice, Molecular Sequence Data, Carps genetics, Genes, Mitochondria genetics, RNA, Transfer, Phe genetics
- Abstract
A nucleotide sequence for the tRNA(phe) gene of Carp mitochondria was determined. Sequence data comparisons made among the whale, human, Xenopus laevis, bovine, mouse, chicken and carp, showed that a novel conservative structure was found in the D. stem (dihydrouridine stem), which was known had variant nucleotides in any other vertebrate mitochondrial tRNA and cytoplasmic tRNA genes. This conservative structures contains 13 bp. When we compared the front 7 bp of the conservative structure with the eukaryotic RNA Pol III recognitive A domain, we found these two kinds of different species had partly homologue. As the mitochondrial tRNA(phe) gene is located between the displacement loop and mitochondrial rRNA gene, we inferred that the novel conservative structure might have some extra interesting functions.
- Published
- 1996
241. Liver and intestinal flukes.
- Author
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Liu LX and Harinasuta KT
- Subjects
- Animals, Clonorchis sinensis physiology, Echinostomiasis parasitology, Fasciola physiology, Humans, Opisthorchis physiology, Clonorchiasis parasitology, Fascioliasis parasitology, Fasciolidae physiology, Opisthorchiasis parasitology, Trematode Infections parasitology
- Abstract
A number of trematodes besides schistosomes parasitize humans and domesticated animals. Although they do not have as great a public health impact as schistosomiasis, they are prevalent in Southeast Asia as well as among the greater than 1 million immigrants from this region to North America. The human biliary flukes include C. sinensis, O. viverrini, and O. felineus. These chronic infections are often asymptomatic but over time may cause biliary thickening, cholangitis, and a predisposition to cholangiocarcinoma. Zoonotic trematode infections include the sheep liver fluke F. hepatica and the intestinal flukes Fasciolopsis, Echinostoma, Heterophyes, and Metagonimus.
- Published
- 1996
- Full Text
- View/download PDF
242. Antiparasitic drugs.
- Author
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Liu LX and Weller PF
- Subjects
- Humans, Anthelmintics therapeutic use, Antiprotozoal Agents therapeutic use, Helminthiasis drug therapy, Protozoan Infections drug therapy
- Published
- 1996
- Full Text
- View/download PDF
243. [Care of photorefractive keratectomy].
- Author
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Liu LX, Gong SZ, and Lei M
- Subjects
- Humans, Lasers, Excimer, Photorefractive Keratectomy nursing
- Published
- 1996
244. Presence of the seven transmembrane thrombin receptor on human tumour cells: effect of activation on tumour adhesion to platelets and tumor tyrosine phosphorylation.
- Author
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Nierodzik ML, Bain RM, Liu LX, Shivji M, Takeshita K, and Karpatkin S
- Subjects
- Blotting, Southern, Cell Adhesion physiology, DNA Primers genetics, Humans, Immunoblotting, Molecular Sequence Data, Phosphorylation, Polymerase Chain Reaction, Tumor Cells, Cultured, Tyrosine metabolism, Peptide Fragments pharmacology, Platelet Activation, Receptors, Thrombin drug effects
- Abstract
Thrombin-treated tumour cells enhance their adhesion to platelets, fibronectin and von Willebrand factor in vitro, and enhanced their pulmonary metastasis in mice in vivo. A unique seven transmembrane spanning thrombin receptor has recently been cloned which is activated following thrombin proteolysis of the N-terminal end of the receptor with exposure of a tethered ligand. An N-terminal 14-mer (SFLLRNPNKYEPF) or 6-mer (SFLLRN) of the tethered ligand can serve as a thrombin receptor activation peptide (TRAP) by mimicking the action of thrombin on platelets, endothelial cells and smooth muscle cells. We have examined six human tumour cell lines for their response to TRAP, for the presence of this thrombin receptor mRNA by RT-PCR, protein by immunoblot and for their in vitro and in vivo response to TRAP. All six cell lines contain the receptor mRNA, and when treated with 100 microM 6-mer TRAP or 1 u/ml thrombin increase their adhesion to platelets 2-3-fold. Four of the six cell lines undergo tyrosine phosphorylation within 30 s to 1 min after exposure to 6-mer TRAP or thrombin. Thus tumour cells respond to thrombin via activation of their seven transmembrane spanning thrombin receptor.
- Published
- 1996
- Full Text
- View/download PDF
245. Heterogenous inhibition of platelet aggregation by monoclonal antibodies binding to multiple sites on GPIIIa.
- Author
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Liu LX, Nardi MA, Nierodzik ML, and Karpatkin S
- Subjects
- Antibodies, Monoclonal metabolism, Blood Platelets metabolism, Enzyme-Linked Immunosorbent Assay, Fibrinogen metabolism, Humans, Immunoblotting, Peptides pharmacology, Phosphorylation drug effects, Platelet Aggregation drug effects, Platelet Aggregation Inhibitors pharmacology, Platelet Glycoprotein GPIIb-IIIa Complex metabolism, Protein Binding, Structure-Activity Relationship, Thrombin pharmacology, Viper Venoms pharmacology, Antibodies, Monoclonal immunology, Platelet Aggregation immunology, Platelet Glycoprotein GPIIb-IIIa Complex immunology
- Abstract
Six monoclonal IgG1-k antibodies (LK2, LK3r, LK4-55, LK5, LK6-55, LK7r) were raised against platelet membrane GPIIIa in order to study the structure-function relationship of this molecule. Antibodies were selected on their ability to react with GPIIIa by ELISA on adherent platelets, by immunoblot on platelet lysates and by fluorescence flow cytometry on intact platelets. Fluorescence reactivity varied from 3- to 202-fold greater than isotype control fluorescence. Two MoAbs reacted on immunoblot under reduced conditions (LK7r and LK3r). Two reacted with a 55 kD chymotrypsin/subtilisin digest of GPIIIa which is likely to exclude amino acids 121-348 (LK4-55 and LK6-55). Four of the MoAbs (LK5, LK3r, LK2 and LK4-55) inhibited tyrosine phosphorylation of one to four distinct bands on immunoblot. LK4-55 reacted with an N-terminal 66 amino acid fusion protein of GPIIIa near the PLA epitope (Leu 33). LK7r reacted with a 212-222 peptide reported to be an RGD fibrinogen binding site. LK2 reacted near a disintegrin-RGD binding site. Except for LK5, all inhibited ADP, collagen and thrombin-induced platelet aggregation in a heterogeneous fashion. Percentage inhibition of 125I-fibrinogen binding to platelets varied from 18% to 98%. No correlation was noted between inhibition of fibrinogen binding, location of MoAb binding on GPIIIa, reactivity of MoAb binding with GPIIIa, inhibition of thrombin-induced tyrosine phosphorylation or inhibition of platelet aggregation induced by ADP, collagen or thrombin. Thus MoAbs, binding to platelet GPIIIa at different sites, inhibit platelet aggregation in a heterogeneous manner.
- Published
- 1995
- Full Text
- View/download PDF
246. Eosinophilic colitis associated with larvae of the pinworm Enterobius vermicularis.
- Author
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Liu LX, Chi J, Upton MP, and Ash LR
- Subjects
- Adolescent, Animals, Anthelmintics therapeutic use, Base Sequence, Diarrhea parasitology, Enterobiasis drug therapy, Enterobius isolation & purification, Enterocolitis drug therapy, Eosinophilia drug therapy, Humans, Larva, Male, Molecular Sequence Data, Oligonucleotide Probes, Enterobiasis parasitology, Enterocolitis parasitology, Eosinophilia parasitology
- Abstract
Various helmintic parasites, most of which are uncommon in economically developed countries, can cause abdominal pain and eosinophilic inflammation of the bowel. A homosexual man presented with severe abdominal pain and haemorrhagic colitis, eosinophilic inflammation of the ileum and colon, and numerous unidentifiable larval nematodes in diarrhoeal stool. His symptoms resolved with anthelmintic treatment alone. Using comparative morphology and molecular cloning of nematode ribosomal RNA genes, we identified the parasites as larvae of the pinworm Enterobius vermicularis, which are rarely observed or associated with disease. Occult enterobiasis is widely prevalent and may be a cause of unexplained eosinophilic enterocolitis.
- Published
- 1995
- Full Text
- View/download PDF
247. [Familial cervical lung hernia: a report of 4 cases in a family].
- Author
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Chen RD, Liu XD, and Liu LX
- Subjects
- Adult, Child, Child, Preschool, Female, Hernia diagnostic imaging, Hernia genetics, Humans, Lung Diseases diagnostic imaging, Male, Middle Aged, Pedigree, Tomography, X-Ray Computed, Genes, Dominant, Lung Diseases genetics
- Abstract
In this study 4 members of three generations in one family suffered cervical lung hernia was reported. In this 4 cases, there were 2 males, and 2 females, and 3 cases found on the right side, 1 on the left side of neck. Their ages were 55, 32, 5 and 6, respectively. X-ray examinations and CT scan showed typical characteristics. Chromosome examination analysis with high resolution G band was done for 2 of them, no abnormal changes were found. From pedigree analysis we think this type of disease is an autosomal dominant hereditary disease. This familial abnormality has not been found in medical literature, and so we suggest a namelity "Familial cervical lung hernia".
- Published
- 1994
248. Human ehrlichiosis in New England.
- Author
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Rynkiewicz DL and Liu LX
- Subjects
- Aged, Animals, Arachnid Vectors, Humans, Male, Massachusetts, Ticks, Ehrlichiosis diagnosis
- Published
- 1994
- Full Text
- View/download PDF
249. Strongyloidiasis and other intestinal nematode infections.
- Author
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Liu LX and Weller PF
- Subjects
- Adult, Albendazole adverse effects, Albendazole therapeutic use, Animals, Dogs, Female, Humans, Ivermectin adverse effects, Ivermectin therapeutic use, Male, Middle Aged, Pregnancy, Rats, Thiabendazole adverse effects, Thiabendazole therapeutic use, Intestinal Diseases, Parasitic diagnosis, Intestinal Diseases, Parasitic drug therapy, Intestinal Diseases, Parasitic immunology, Nematode Infections diagnosis, Nematode Infections drug therapy, Nematode Infections immunology, Strongyloides stercoralis physiology, Strongyloidiasis diagnosis, Strongyloidiasis drug therapy, Strongyloidiasis immunology
- Abstract
In contrast to other helminthic parasites, Strongyloides stercoralis can replicate within humans, causing a chronic persistent infection that can be severe and fatal in compromised hosts. This article reviews new developments to help meet the clinical challenges of this infection, including clinical clues to the diagnosis, new diagnostic methods, including stool culture and serological assays, new drugs such as albendazole and ivermectin, and difficult treatment issues. The other major intestinal nematode parasites, including Ascaris, hookworm, and Trichuris, are extremely common worldwide, but in North America their clinical presentation is often more subtly related to low-grade worm burdens or allergic manifestations. Special consideration is given to difficult management issues, including the patient with unexplained eosinophilia, the pregnant patient, and the patient who passes a worm.
- Published
- 1993
250. Eosinophilic meningitis.
- Author
-
Weller PF and Liu LX
- Subjects
- Animals, Humans, Meningitis cerebrospinal fluid, Meningitis diagnosis, Meningitis etiology, Eosinophils, Meningitis parasitology
- Published
- 1993
- Full Text
- View/download PDF
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