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Jian-Sheng Li

Publications and source records attributed to Jian-Sheng Li.

10 recordsLinked to original sources
PubMed2006

Improving QTL mapping resolution based on genotypic sampling--a case using a RIL population.

The QTL mapping results were compared with the genotypically selected and random samples of the same size on the base of a RIL population. The results demonstrated that there were no obvious differences in the trait distribution and marker segregation distortion between the genotypically selected and random samples with the same population size. However, a significant increase in QTL detection power, sensitivity, specificity, and QTL resolution in the genotypically selected samples were observed. Moreover, the highly significant effect was detected in small size of genotypically selected samples. In QTL mapping, phenotyping is a more sensitive limiting factor than genotyping so that the selection of samples could be an attractive strategy for increasing genome-wide QTL mapping resolution. The efficient selection of samples should be more helpful for QTL maker assistant selection, fine mapping, and QTL cloning.

Chromosome Mapping↗
PubMed2006

[Effects of Naomaitong Recipe on expressions of nuclear factor-kappaB and nitric-oxide synthases in brain tissue after focal cerebral ischemia reperfusion in aged rats].

OBJECTIVE: To study the effects of Naomaitong Recipe, a compound Chinese herbal medicine, on the expressions of nuclear factor-kappaB (NF-kappaB) and nitric-oxide synthases (NOSs) in brain tissue after focal cerebral ischemia reperfusion in aged rats and the dosage-effect relationship. METHODS: We adopted the middle cerebral artery occlusion (MCAO) in aged rats as the focal cerebral ischemia model, with 3-hour ischemia and 12-day reperfusion, and observed the changes of the nerve dysfunction score, the water content of cerebral constitution and the expressions of NF-kappaB, heat-shock protein 70 (HSP70) and NOSs in cerebral cortex. RESULTS: The nerve dysfunction score, the water content of cerebral constitution, the expressions of NF-kappaB, HSP70, neuronal nitric-oxide synthase (nNOS), endothelial nitric-oxide synthase (eNOS) and inducible nitric-oxide synthase (iNOS) in the untreated group were higher than those of the sham-operated group. The nerve dysfunction score, the water content of cerebral constitution, the expressions of NF-kappaB, iNOS and nNOS were lower, while the expressions of HSP70 and eNOS were higher in the high-, medium- and low-dose Naomaitong-treated groups and nimodipine-treated group than those of the untreated-group. The nerve dysfunction score and the expression of nNOS were lower, while the expression of eNOS was higher in the medium-dose Naomaitong-treated group than those of the nimodipine-treated group. The expressions of HSP70 and eNOS were higher, while the other indices were lower in the medium-dose Naomaitong-treated group than those of the low-dose Naomaitong-treated group. CONCLUSION: Naomaitong Recipe can protect the brain cells from damage after focal cerebral ischemia reperfusion injury by adjusting the expressions of NF-kappaB, HSP70 and NOSs, and the medium-dose Naomaitong Recipe is more effective.

Aging↗
PubMed2005

[QTL mapping of five agronomic traits in maize].

Agronomic traits have significant influence on stability and adaptability in maize production. In this investigation, using a population with 266 F2:3 families from Yuyu22 (Zong3 x 87-1), two-location field tests were conducted in Wuhan and Xiangfan in 2001, with a randomized complete block design, to characterize five agronomic traits: ear height, tassel branch number, stalk diameter, days to pollen, and days to silk. Correlation analysis of field performance indicated that ear height, tassel branch number and stalk diameter were significantly positive correlative with single-plant yield, days to pollen and days to silk were highly positive correlative with each other, and tassel branch number was significantly positive correlative with stalk diameter too. Utilizing data of field tests and molecular markers, Composite Interval Mapping (CIM) method was used to localize the quantitative trait loci of these traits and 500 times permutation test was conducted to have proper LOD threshold value. As the results, total seven QTL of ear height, nine QTL of tassel branch number, eight QTL of stalk diameter, nine QTL of days to pollen, and seven QTL of days to silk were mapped on 10 chromosomes of maize; all of these QTL distributed unevenly on chromosomes and trended to cluster together. According to analysis of this investigation, the phenotype correlations of quantitative traits may result from the correlations of QTL controlling those traits. Those will be helpful to further understand genetic basis of agronomic traits in maize.

Chromosome Mapping↗
PubMed2005

[Isolation of maize genes related to aluminum tolerance].

To investigate gene expression profile in response to aluminum stress and to cloning the key genes related to aluminum tolerance, are crucial to genetic improvement of plant aluminum tolerance. In this study, suppression subtractive hybridization method was adopted to construct SSH-cDNA libraries at seedling stage of two maize inbred lines (Fig. 1), of which Mo17 is sensitive to aluminum toxicity and TL94B is tolerant. As a result, a forward SSH-cDNA library including 762 clones and a reverse SSH-cDNA library including 382 clones were constructed for Mo17. In the same way, a forward SSH-cDNA library including 760 clones and a reverse SSH-cDNA library including 380 clones were constructed for TL94B. Identification of these SSH-cDNA libraries shows that the length of inserted fragments ranges from 250 bp to 1.0 kb (Fig. 2), of which nearly 18% are positive clones. Through differential hybridization screening (Fig. 3), 124 and 47 positive clones were screened from forward and reverse SSH-cDNA libraries of Mo17 respectively; 103 and 64 positive clones from forward and reverse SSH-cDNA libraries of TL94B respectively. Total 338 positive clones from four SSH-cDNA libraries were sequenced, and all of the sequences of inserted fragments were analyzed using bioinformatical methods. A total of 232 kinds of EST sequences were obtained. Among these ESTs, 70.2% had significant homology with known genes, and the remaining 29.8% were function-unknown including 21 kinds of newly found ESTs (Table 1). An aluminum tolerant gene, GDP dissociation inhibitor gene, was detected its expression character by Northern hybridization (Fig. 4). These results indicate that the responses of maize to aluminum stress involve the interactions among different signal/metabolism pathways, such as signal transduction of stress-related factors, transcription and regulation of responsive genes, synthesis and transport of substances, changes in cell structures and functions.

Adaptation, Physiological↗
PubMed2004

[Comparative analyses of QTL for important agronomic traits between maize and rice].

The objective of this study was to assess syntenic relationships of quantitative trait loci (QTL) for important agronomic traits between maize and rice based on the comparative genomic map of maize and rice using two F(2:3) populations. Through the comparisons, it was observed that there were extensive conserved relationships of maize QTL affected plant height, row number, and kernels per row with rice QTL affected plant height, tillers per plant, and grains per panicle respectively. Sixteen of 45 QTL affecting five different maize traits were conserved compared with 12 of 38 QTL affecting five different rice traits, which provided some useful information for locating, isolating and cloning maize QTL by using the rice genomic data. In this study, one QTL in rice usually had two conserved QTL in maize, further supporting the hypothesis that there is a polyploidization event during maize evolution. It was interested in observing that there were QTL rich regions on chromosomes in maize and rice, where QTL affecting different traits were usually clustered. These results revealed that the QTL affected the same or similar traits in maize and rice may have the common origin. These results will be helpful to map, isolate and clone QTL in large genome crops, such as maize, by using rice genome information, as well as to understand the evolutionary forces that structured the organization of the grass genomes.

Oryza↗
PubMed2003

Octreotide acts as an antitumor angiogenesis compound and suppresses tumor growth in nude mice bearing human hepatocellular carcinoma xenografts.

PURPOSE: To investigate the effect of octreotide on angiogenesis induced by human hepatocellular carcinoma (HCC) and to evaluate whether octreotide can suppress tumor growth in nude mice bearing human HCC xenografts through inhibition of angiogenesis. METHODS: Using MTT assay, invasion assay, migration assay, and Matrigel assay, the effects of octreotide on endothelial cells stimulated by vascular endothelial growth factor (VEGF) were evaluated in vitro. MTT assay was also used to investigate the effects of octreotide on human HCC cells with high (MHCC97-H) and low (MHCC97-L) metastatic potential that were established from the animal model of human HCC LCI-D20 in nude mice. The expression of somatostatin receptor (SSTR) subtypes in human umbilical vein endothelial cells (HUVECs), MHCC97-H, and MHCC97-L cells was detected by RT-PCR analysis. An LCI-D20 corneal micropocket model in nude mice was used to evaluate the effect of octreotide on angiogenesis induced by human HCC in vivo. Male nude mice were subcutaneously implanted with LCI-D20 tumor tissues for the tumor xenograft studies. Microvessel density was analyzed in CD34-stained tumor sections by the immunohistochemical SP method. RESULTS: In vitro, octreotide inhibited the proliferation, invasion, and differentiation of HUVECs elicited by VEGF. RT-PCR analysis demonstrated that HUVECs expressed the somatostatin receptor subtype SSTR3. In vivo, octreotide was sufficiently potent to suppress nude mice corneal neovascularization induced by tumor tissues from LCI-D20. Systemic administrations of octreotide produced a significant suppression of the growth of LCI-D20. In cell culture, MHCC97-H and MHCC97-L cells were insensitive to octreotide at concentrations that significantly inhibited endothelial cells proliferation. The HCC cells used did not express any known SSTRs. Immunohistochemical studies of tumor tissues revealed decreased microvessel density in octreotide-treated animals as compared with controls. CONCLUSIONS: The present study demonstrates that the somatostatin analogue octreotide is a potent antitumor angiogenesis compound and the antiproliferative effect of octreotide on tumor growth in nude mice bearing HCC xenografts may be mediated, at least in part, by its suppressive effect on blood vessel supply. The somatostatin analogue octreotide might provide a useful and relatively nontoxic adjuvant therapy in the treatment of HCC.

Animals↗
PubMed2003

[Research on quantified diagnosis and combining diseases with syndrome of blood stasis].

OBJECTIVE: To explore the way of quantified diagnosis of blood stasis syndrome (BSS) and the essence of BSS. METHODS: Using t-test and logistic regression to analyze the symptoms, signs, and objective indexes of BSS in clinical test. RESULTS: (1) The levels of endothelin, nitric oxide, and t-PA between 182 patients with BSS and non-BSS had notable difference. (2) The stepwise regression analysis about hemoglobin, triglyceride, total cholesterol, endothelin, nitric oxide, and t-PA in 170 patients with BSS or non-BSS revealed that the order of these indexes considering their importance was: endothelin, hemoglobin, t-PA, nitric oxide. However, the triglyceride and total cholesterol could not enter the regression equations. (3) The stepwise regression analysis about 40 symptoms and signs in 601 patients with BSS or non-BSS revealed that the 18 items had the very contribution to diagnose the BSS when the F value was 6, and so a regression equation was available. The total coincidence ratio was 94.24% when the other quantified data about BSS were tested in the equation. CONCLUSION: The standardized TCM syndrome, which accorded with the criteria of combining diseases with syndrome, was made up of symptoms, signs, and objective indexes. The standard could be obtained by multi-center, prospective, random and controlled clinical epidemiological survey and clinical test.

Adult↗
PubMed2003

[Genetic analysis of segregation distortion of molecular markers in maize F2 population].

A genetic linkage map of maize was constructed using 150 SSR and 24 RFLP markers, with F2 population from an elite hybrid (Zong3 x 87-1). Among 174 markers, covering whole maize 10 chromosomes, 49 markers (28.1%) showed the genetic distortion (P < 0.05). Of the total segregation distortion markers, 11 markers (22.5%) deviated toward male parent, Zong3, while 12 markers (24.5%) deviated toward female parent, 87-1, besides 25 markers (51.0%) distorted to heterozygote. Only one marker distorted to both parents. Totally, 14 segregation distortion regions (SDRs) were detected among 9 different chromosomes. Four of them were located in near regions where gametophyte genes were mapped, indicating that segregation distortion may be caused by gametophyte genes partially. Two segregation distortion regions, SDR6-1 and SDR7-1, detected in this study, seemed to be new segregation distortion regions. In this paper, reasons for segregation distortion and effects of segregation distortion on genetic mapping and QTL analysis were discussed. Regarding to QTL analysis with single locus, segregation distortion would not affect QTL mapping, but regarding to analysis of digenic interactions for epistasis, the fewer distortion markers and larger size population would be needed.

Chromosome Mapping↗
PubMed2003

[Maize starch biosynthesis and its genetic manipulation].

Starch is the most important source of calories and a vital storage component in plants. The characterization and production of starch variants from mutation and with transgenic technology has improved our understanding of the synthesis of starch granule. In starch biosynthesis in plants, four enzymes, including ADP-glucose pyrophosphorylase, starch synthase, starch branching enzyme and starch debranching enzyme, are widely accepted from an enormous amount of research aimed primarily at enzyme characterization. As many genes encoding the enzymes and their multiple isoforms in starch biosynthesis pathway have been isolated, genetic manipulation of the starch biosynthesis pathway shows to be a practical way by which starch quantity is increased and starch with novel properties can be created.

English Abstract↗