Biomedical subjects

Lin He

Publications and source records attributed to Lin He.

At least 163 records · Page 9Linked to original sources

PubMed2004

[Formation and function of coronary collateral circulation and their influencing factors].

OBJECTIVE: To clarify the formation and function of coronary collateral circulation (CCC) in coronary artery disease (CAD) patients with severe coronary artery stenosis and their influencing factors. METHODS: Coronary angiography was performed on 266 CAD patients with severe coronary stenosis. CCC formation was evaluated by Rentrop rating on those 266 patients and 401 severe stenosis arteries; while in CCC formed patients, CCC function was evaluated by Werner collateral collection (CC) rating. The formation, function of CCC and their influencing factors were analyzed and compared. RESULTS: CCC formation in those severe stenosis coronary arteries was related to the severity of coronary stenosis: the forming rate of CCC was 42.6% in vessels with 90%-94% stenosis (Group A), 56.9% with 95%-99% stenosis (Group B) and 93.0% with 100% stenosis (Group C) (p <0 .01). Between CCC forming and non-forming groups, there was no significant difference in age, gender, incidence of MI, hypertension and diabetes, history of smoking and serum levels of HDL-C and LDL-C (P > 0.05). In the CCC formation group, serum HDL-C level was the highest in the CC Grade 2 group (according to Werner function rating) and the lowest in the CC Grade 0 group (P < 0.05). Whereas, LDL-C level was the lowest in the CC Grade 2 group and the highest in the CC Grade 0 group (P < 0.05). CONCLUSION: Severity of coronary stenosis was the major influencing factor in CCC formation and function, and the rate of CCC formation increased with the exacerbation of coronary stenosis. Serum HDL-C and LDL-C level had no relationship with CCC formation, but related to CCC function. Better CCC function was found in patients with high level of HDL-C whereas the patients with high level of LDL-C had spoiled CCC function.

Cholesterol, HDL↗

PubMed2003

Association analysis of polymorphisms in the upstream region of the human dopamine D4 receptor gene in schizophrenia.

Several studies have suggested that the transcriptional activity of the DRD4 gene may exert an important role in susceptibility to schizophrenia. To address this issue, we studied the association of schizophrenia and polymorphisms including -616C>G, -603T>del, -602G>del, 600G>C, -521C>T, -376C>T and a 120 bp tandem duplication polymorphism (120 bp repeat) in 1.2 kb upstream from the initiation codon in the promoter region of the DRD4 gene with 210 schizophrenic cases and 206 healthy controls. The results showed a significant excess of allele L of the 120 bp repeat in the schizophrenic patients compared to the controls (X(2)=8.585, df=1, P=0.003, OR=1.546, 95% CI=1.154-2.070). No significant difference was detected in the frequencies of genotype and allele of six other polymorphisms between the two groups. However, haplotypic distribution of 120 bp repeat, -616C>G, -602G>del, -521C>T and -376C>T was significantly different between case and control groups (P=0.005). This might cause the alteration of the transcriptional regulation of the DRD4 gene, as the consensus sequences of binding sites for several known transcription factors are involved in this region.

Adult↗

PubMed2003

C-reactive protein stimulates MMP-1 expression in U937 histiocytes through Fc[gamma]RII and extracellular signal-regulated kinase pathway:: an implication of CRP involvement in plaque destabilization.

OBJECTIVE: It has been shown that plasma level of C-reactive protein (CRP) is an independent predictor for acute coronary syndromes and is associated with plaque weakening. However, the underlying mechanisms are not well understood. In this study, we investigated the effect of CRP on the expression of matrix metalloproteinase-1 (MMP-1) that has been implicated in plaque vulnerability by human U937 histiocytes and monocyte-derived macrophages. METHODS AND RESULTS: Enzyme-linked immunosorbent assay of MMP-1 in conditioned medium showed that treatment of U937 cells with 100 microg/mL of CRP for 24 hour led to a 3- to 5-fold increase in MMP-1 secretion. CRP also markedly stimulated MMP-1 release from human monocyte-derived macrophages. In contrast, CRP had no effect on tissue inhibitor of metalloproteinase-1 (TIMP-1) secretion. Northern blot showed that CRP upregulated MMP-1 mRNA expression. Collagenase activity assay showed that CRP increased collagen-degrading activity in cell-conditioned medium. Furthermore, results showed that the stimulation of MMP-1 secretion by CRP was inhibited by anti-CD32, but not by anti-CD64 antibody, and by mitogen-activated protein kinase/extracellular signal-regulated kinase (MEK) inhibitor PD98059. Finally, Western blot showed that CRP stimulated phosphorylation of extracellular signal-regulated kinase. CONCLUSIONS: This study demonstrates that CRP stimulates MMP-1 expression by U937 cells through FcgammaRII and extracellular signal-regulated kinase pathway. These findings suggest that CRP may promote matrix degradation and thus contribute to plaque vulnerability.

Arteriosclerosis↗

PubMed2003

A novel locus for parietal foramina maps to chromosome 4q21-q23.

Parietal foramina [PFM], inherited usually in an autosomal dominant mode, is an extremely rare developmental defect characterized by a symmetrical, oval hole in the parietal bone. It can be present as either an isolated or a syndromic feature. PFM types 1 and 2 (PFM1 and PFM2) have been found to be caused by mutations in the MSX2 and ALX4 genes, located to chromosomes 5 and 11, respectively. After exclusion of both the above loci in a large Chinese pedigree with autosomal dominant PFM, a genome-wide search revealed a linkage of the PFM to markers at the 4q21-q23 region. The maximum LOD score from two-point linkage analysis is 3.87 for marker D4S2961. Analysis of co-segregated haplotype localized the region to a 20-cM interval that flanks D4S392 and D4S2945. Therefore, we concluded that the PFM in the family is a new PFM locus. Although three genes, BMPR1B, PP1 and IBSP, are located to 4q21-q25 and their functions are related to bone morphogenesis, no mutations were identified by sequencing analysis of their exons.

Chromosome Mapping↗

PubMed2003

Evidence for a major susceptibility locus at 11q22.1-23.3 has been detected in a large Chinese family with pure grand mal epilepsy.

Pure grand mal epilepsy (PGME) is a common subtype of idiopathic generalized epilepsy (IGE) with an unclear mode of inheritance. Several studies with the multiple families have provided evidence for the disorder to be linked to chromosome 8q24 and 8p. In this work, we performed an autosomal-wide scan linkage analysis using microsatellite markers in a large Chinese family with PGME and found seven markers with likelihood of odds (LOD), scores >/=1.0 (theta=0) in chromosome 11q22.1-23.3. The highest LOD score for two-point and multi-point linkage analysis are 1.99 (theta=0) at marker D11S4159 and 2.18 between markers D11S1782 and D11S3178, respectively, which reached the level of a suggested positive linkage LOD score (Z>/=1.9), under an autosomal dominant manner of inheritance with a penetrance of 65% but no significant positive LOD score (Z>/=3.3) was found after high density of microsatellite markers used in the regions. Obviously, our data do not support the linkage of the disease to chromosome 8q24 and 8p but implicate that chromosome 11q22.1-23.3 may be a new locus linked to PGME, which indicates the existence of genetic heterogeneity in the disorder.

Adolescent↗

PubMed2003

Association of APOE gene with schizophrenia in Chinese: a possible risk factor in times of malnutrition.

Five hundred and seventy nine Chinese patients with schizophrenia who met DSMIV criteria for the disorder were genotyped for alleles epsilon 2,3,4 of apolipoprotein E (APOE) gene. All were recruited from inpatients and outpatients attending a large mental health centre in Shanghai. Results were compared to APOE data on 1528 controls drawn from the same area. Major differences in APOE genotype ratios and allele frequencies were observed between the patients and controls. The patients with schizophrenia had highly significantly (p<0.0001) increased epsilon 4/-genotypes and allele frequencies, and decreased epsilon 3/3 genotypes and epsilon 3 allele frequencies compared to controls. The effect was independent of sex and/or age of onset of illness, but strongly influenced by date of birth. Significant differences were restricted to individuals with schizophrenia born either before 1949 or during the period 1958-1967. Both were times of severe food shortages and malnutrition. We suggest that APOE may operate as an additional risk factor for schizophrenia in individuals subjected to fetal and/or early postnatal malnutrition.

Adult↗

PubMed2003

A novel insertion mutation in spastin gene is the cause of spastic paraplegia in a Chinese family.

A total of eight loci for autosomal dominant hereditary spastic paraplegia (ADHSP) has been mapped to chromosome 14q, 2p, 15q, 8q, 10q, 12q, 19q, 2q, respectively, among which the SPG4 gene on chromosome 2p21-22 encoding spastin, an ATPase of the AAA family, accounts for 40-50% of all ADHSP families and is expressed in both adult and fetal tissues. In this work, we reveal a novel insertion mutation in exon 11 of the SPG4 gene found in a big Chinese family composed of 47 members, including 20 affected ones, using linkage analysis. The mutation was well demonstrated to be the cause of loss of production of the functional protein by pre-termination of translation in AAA cassette region. To our knowledge, this is the first report of spastin mutation in China.

Adenosine Triphosphatases↗

PubMed2003

A gene locus responsible for dyschromatosis symmetrica hereditaria (DSH) maps to chromosome 6q24.2-q25.2.

Dyschromatosis symmetrica hereditaria (DSH) is a hereditary skin disease characterized by the presence of hyperpigmented and hypopigmented macules on extremities and face. The gene, or even its chromosomal location, for DSH has not yet been identified. In this study, two Chinese families with DSH were identified and subjected to a genomewide screen for linkage analysis. Two-point linkage analysis for pedigree A (maximum LOD score [Z(max)] = 7.28 at recombination fraction [theta] = 0.00) and pedigree B (Z(max) = 2.41 at theta = 0.00) mapped the locus for DSH in the two families to chromosome 6q. Subsequent multipoint analysis of the two families also provided additional support for the DSH gene being located within the region 6q24.2-q25.2, with Z(max) = 10.64. Haplotype analysis confined the locus within an interval of 10.2 Mbp, flanked by markers D6S1703 and D6S1708. The two families had no identical haplotype within the defined region, which suggests that the two families were different in origin. Further work on identification of the gene for DSH will open new avenues to exploration of the genetics of pigmentation.

China↗

PubMed2003

A family-based association study of T1945C polymorphism in the proline dehydrogenase gene and schizophrenia in the Chinese population.

Previous studies have reported genetic linkage evidence for a candidate gene of schizophrenia on chromosome 22q11 but no genes in this region have been really confirmed to be involved in the etiology of schizophrenia so far. Very recently, the proline dehydrogenase gene (PRODH), located in the most centromeric part of the 22q11 microdeletion region, has been reported to be strongly associated with schizophrenia from three sets of independent samples and the most significant evidence for association was derived from a single nucleotide polymorphism-PRODH*1945(T/C). We genotyped this polymorphism in 166 Chinese family trios with schizophrenia from East China. No evidence for preferential transmission of the PRODH*1945 alleles from parents to affected offsprings was found using either Transmission Disequilibrium Test (P=0.4) or Haplotype-based Haplotype Relative Risk analysis (P=0.35). Our results suggest that the 1945(T/C) polymorphism of the proline dehydrogenase gene is unlikely to play a major role in the susceptibility to schizophrenia in the Chinese population.

China↗

PubMed2003

Spongiform degeneration in mahoganoid mutant mice.

mahoganoid is a mouse coat-color mutation whose pigmentary phenotype and genetic interactions resemble those of Attractin (Atrn). Atrn mutations also cause spongiform neurodegeneration. Here, we show that a null mutation for mahoganoid causes a similar age-dependent neuropathology that includes many features of prion diseases but without accumulation of protease-resistant prion protein. The gene mutated in mahoganoid encodes a RING-containing protein with E3 ubiquitin ligase activity in vitro. Similarities in phenotype, expression, and genetic interactions suggest that mahoganoid and Atrn genes are part of a conserved pathway for regulated protein turnover whose function is essential for neuronal viability.

Alleles↗

PubMed2003

A locus for congenital preauricular fistula maps to chromosome 8q11.1-q13.3.

The incidence of congenital preauricular fistula (CPF) is >1.1% in both Chinese and Caucasians, but it is even higher in Blacks. We mapped the locus for CPF to chromosome 8q11.1-q13.3 by linkage analysis of a family composed of 7 affected and 11 nonaffected members. The two-point LOD score was 2.40, shown by markers D8S285 and D8S1113 at a recombination fraction (theta) of 0.00. Results from three other markers (D8S1110, D8S260, and D8S1136) in the same region further support the linkage. Haplotype analysis for this family confined the locus to within an interval of approximately 26.7 cM, flanked by markers D8S532 and D8S279. A LOD score of <3 is likely due to the limitation of family size.

Chromosome Mapping↗

PubMed2003

Nanoparticles for bioanalysis.

This review covers the emerging field of nanobiotechnology, in which nanoparticles are applied to the analysis of biomolecules. Nanoparticles can be used in a variety of bioanalytical formats, and this review discusses four classes of use. First, nanoparticles as quantitation tags, such as the optical detection of quantum dots and the electrochemical detection of metallic nanoparticles. Second, encoded nanoparticles as substrates for multiplexed bioassays, such as striped metallic nanoparticles. Third, nanoparticles that leverage signal transduction, for example in colloidal gold-based aggregation assays. Fourth, functional nanoparticles that exploit specific physical or chemical properties of nanoparticles to carry out novel functions, such as the catalysis of a biological reaction. In addition, the review discusses the next generation of nanoparticles that will be utilized in the life sciences, such as nanodots and carbon nanotubes.

Biosensing Techniques↗

PubMed2003

Application of pseudo amino acid composition for predicting protein subcellular location: stochastic signal processing approach.

The function of a protein is closely correlated with its subcellular location. With the success of human genome project and the rapid increase in the number of newly found protein sequences entering into data banks, it is highly desirable to develop an automated method for predicting the subcellular location of proteins. The establishment of such a predictor will no doubt expedite the functionality determination of newly found proteins and the process of prioritizing genes and proteins identified by genomics efforts as potential molecular targets for drug design. Based on the concept of pseudo amino acid composition originally proposed by K. C. Chou (Proteins: Struct. Funct. Genet. 43: 246-255, 2001), the digital signal processing approach has been introduced to partially incorporate the sequence order effect. One of the remarkable merits by doing so is that many existing tools in mathematics and engineering can be straightforwardly used in predicting protein subcellular location. The results thus obtained are quite encouraging. It is anticipated that the digital signal processing may serve as a useful vehicle for many other protein science areas as well.

Algorithms↗

PubMed2003

Accessory proteins for melanocortin signaling: attractin and mahogunin.

Switching from eumelanin to pheomelanin synthesis during hair growth is accomplished by transient synthesis of Agouti protein, an inverse agonist for the melanocortin-1 receptor (Mc1r). The coat color mutations mahogany and mahoganoid prevent hair follicle melanocytes from responding to Agouti protein. The gene mutated in mahogany, which is also known as Attractin (Atrn), encodes a type I transmembrane protein that functions as an accessory receptor for Agouti protein. We have recently determined that the gene mutated in mahoganoid, which is also known as Mahogunin (Mgrn1), encodes an E3 ubiquitin ligase. Like Attractin, Mahogunin is conserved in invertebrate genomes, and its absence causes a pleiotropic phenotype that includes spongiform neurodegeneration.

Agouti Signaling Protein↗

PubMed2003

Genome-wide search for loss of heterozygosity in Chinese patients with sporadic colorectal cancer.

In an attempt to integrally investigate the loss of tumor suppressor genes and search for putative suppressor loci associated with tumor occurrence and progression, we conducted a genome-wide loss of hetero zygosity (LOH) study of 83 tumor samples obtained from Chinese patients with sporadic colorectal cancer. We employed 400 fluorescence-labeled microsatellite marker primers to amplify the corresponding loci of the genomic DNA and then electrophoresed the polymerase chain reaction products and analyzed the fluorescent signals. The LOH frequencies were high (>35%) but were not associated with the tumor stage and progression in 20 loci, including the regions where TP53, E-cadherin, deleted in colorectal carcinoma (DCC), phosphatase and tensin homolog deleted on chromosome 10 (PTEN), mothers against decapentaplegic, Drosophila, homolog of 2 (MADH2) and mothers against decapentaplegic, Drosophila, homolog of 4 (MADH4) reside. Loss of other loci, including two narrow regions on chromosome 2, was found to relate to the tumor stage, suggesting that this genomic instability may contribute to tumor progression.

Adult↗

PubMed2003

[Polymorphism of two novel SNPs, which locate on chromosome 9p21-22, in Han Chinese of Hunan].

OBJECTIVE: To search novel SNPs in exons and regulatory regions of CDKN2A and two novel putative tumor suppressor genes NGX6 and UBAP1, which all reside on chromosome 9p21-22. METHODS: The exons and regulatory regions of those genes were amplified and sequenced in 96 subjects. RESULTS: Two novel SNPs were found, one resides on the sixth exon of UBAP1 gene and the other on the fourth exon of CDKN2A gene. Two novel SNPs were submitted to the dbSNP database, and their access ID are rs3135929 and rs3088440. The polymorphic information contents of them are 0.102 and 0.213 respectively. There is linkage equilibrium between them, and the polymorphic information content of their haplotype is 0.302, higher than any of them individually. CONCLUSION: The polymorphic information content can be improved by using haplotype analysis of several SNPs.

Asian People↗

PubMed2003

[Transmission disequilibrium test of polymorphisms of serotonin transporter gene and schizophrenia based on family trios].

OBJECTIVE: To investigate the relationship between two polymorphisms (Intronic VNTR and 5-HTTLPR) of the serotonin transporter gene and schizophrenia. METHODS: A set of 314 schizophrenic trio samples collected from Shanghai, Xi'an and Jilin regions of China independently was subjected to analysis of the polymorphisms by transmission/disequilibrium test(TDT). RESULTS: No significantly preferential transmission of any allele was detected from both polymorphisms investigated. CONCLUSION: The results suggest that the serotonin transporter gene is unlikely to have a major contribution to susceptibility to schizophrenia in Han Chinese population.

Adult↗

PubMed2003

[Progress in molecular biology study of DNA computer].

DNA (deoxyribonucleotide acids) computer is an emerging new study area that basically combines molecular biology study of DNA molecules and computational study on how to employ these specific molecules to calculate. In 1994 Adleman described his pioneering research on DNA computing in Science. This is the first experimental report on DNA computer study. In 2001 Benenson et al published a paper in Nature regarding a programmable and autonomous DNA computing device. Because of its Turing-like functions, the device is regarded as another milestone progress for DNA computer study. The main features of DNA computer are massively parallel computing ability and potential enormous data storage capacity. Comparing with conventional electronic computers, DNA molecules provide conceptually a revolution in computing, and more and more implications have been found in various disciplines. DNA computer studies have brought great progress not only in its own computing mechanisms, but also in DNA manipulation technologies especially nano-technology. This article presents the basic principles of DNA computer, its applications, its important relationship with genomic research and our comments on all above issues.

Computers, Molecular↗