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Jianjun Liu

Publications and source records attributed to Jianjun Liu.

49 records · Page 3Linked to original sources
PubMed2003

A genomewide screen of 345 families for autism-susceptibility loci.

We previously reported a genomewide scan to identify autism-susceptibility loci in 110 multiplex families, showing suggestive evidence (P <.01) for linkage to autism-spectrum disorders (ASD) on chromosomes 5, 8, 16, 19, and X and showing nominal evidence (P <.05) on several additional chromosomes (2, 3, 4, 10, 11, 12, 15, 18, and 20). In this follow-up analysis we have increased the sample size threefold, while holding the study design constant, so that we now report 345 multiplex families, each with at least two siblings affected with autism or ASD phenotype. Along with 235 new multiplex families, 73 new microsatellite markers were also added in 10 regions, thereby increasing the marker density at these strategic locations from 10 cM to approximately 2 cM and bringing the total number of markers to 408 over the entire genome. Multipoint maximum LOD scores (MLS) obtained from affected-sib-pair analysis of all 345 families yielded suggestive evidence for linkage on chromosomes 17, 5, 11, 4, and 8 (listed in order by MLS) (P <.01). The most significant findings were an MLS of 2.83 (P =.00029) on chromosome 17q, near the serotonin transporter (5-hydroxytryptamine transporter [5-HTT]), and an MLS of 2.54 (P =.00059) on 5p. The present follow-up genome scan, which used a consistent research design across studies and examined the largest ASD sample collection reported to date, gave either equivalent or marginally increased evidence for linkage at several chromosomal regions implicated in our previous scan but eliminated evidence for linkage at other regions.

Autistic Disorder↗
PubMed2003

Genome scan meta-analysis of schizophrenia and bipolar disorder, part III: Bipolar disorder.

Genome scans of bipolar disorder (BPD) have not produced consistent evidence for linkage. The rank-based genome scan meta-analysis (GSMA) method was applied to 18 BPD genome scan data sets in an effort to identify regions with significant support for linkage in the combined data. The two primary analyses considered available linkage data for "very narrow" (i.e., BP-I and schizoaffective disorder-BP) and "narrow" (i.e., adding BP-II disorder) disease models, with the ranks weighted for sample size. A "broad" model (i.e., adding recurrent major depression) and unweighted analyses were also performed. No region achieved genomewide statistical significance by several simulation-based criteria. The most significant P values (<.01) were observed on chromosomes 9p22.3-21.1 (very narrow), 10q11.21-22.1 (very narrow), and 14q24.1-32.12 (narrow). Nominally significant P values were observed in adjacent bins on chromosomes 9p and 18p-q, across all three disease models on chromosomes 14q and 18p-q, and across two models on chromosome 8q. Relatively few BPD pedigrees have been studied under narrow disease models relative to the schizophrenia GSMA data set, which produced more significant results. There was no overlap of the highest-ranked regions for the two disorders. The present results for the very narrow model are promising but suggest that more and larger data sets are needed. Alternatively, linkage might be detected in certain populations or subsets of pedigrees. The narrow and broad data sets had considerable power, according to simulation studies, but did not produce more highly significant evidence for linkage. We note that meta-analysis can sometimes provide support for linkage but cannot disprove linkage in any candidate region.

Bipolar Disorder↗
PubMed2003

Human ADAM33: protein maturation and localization.

ADAM33 (a disintegrin and metalloprotease) was recently found to be a novel asthma susceptibility gene. Domain-specific antibodies were used to study its expression and processing. When the pro-domain and catalytic domain were expressed by a stable-transfected cell line, the pro-domain was removed by cleavage within a putative furin cleavage site. The catalytic domain was active in an alpha(2)-macroglobulin complex formation assay and mutation of the catalytic site glutamic acid (E346A) eliminated activity. In transient transfections using the full-length protein, a pro-form and mature form were detectable and alternate glycosylation was demonstrated at sites within the catalytic domain. ADAM33 was detected on the cell surface, with the majority of protein detected intracellularly. The E346A mutation had no significant effect on protein processing. Endogenous ADAM33 was detected in bronchus tissue, bronchial smooth muscle cells, and MRC-5 fibroblasts, consistent with a role in the pathophysiology of asthma.

ADAM Proteins↗
PubMed2003

A five-year follow-up study on the pathological changes of gastric mucosa after H. pylori eradication.

OBJECTIVES: To investigate the relationship between H. pylori infection, gastric cancer and other gastric diseases through the changes in gastric mucosa and the status of different gastric diseases within 5 years after H. pylori eradication in H. pylori-positive subjects in a high incidence region of gastric cancer. METHODS: One thousand and six adults were selected from the general population in Yantai, Shandong province, a high incidence region for gastric cancer in China. Gastroscopy and Campylobacter-like organism (CLO) testing were performed on all subjects. Biopsy samples from the gastric antrum and body were obtained for histology and assessment of H. pylori infection. All H. pylori-positive subjects were then randomly divided into two groups: treatment group receiving Omeprazole Amoxicillin Clarythromycin (OAC) triple therapy and placebo as controls. These subjects were endoscopically followed up in the second and fifth year. We compared the endoscopic appearance and histology of the biopsy specimens from the same site obtained at the first and last visits. RESULTS: All 552 H. pylori-positive subjects were randomly and evenly divided into treatment group or control group. During the five-year follow-up, the numbers of patients who continued to be negative or positive for H. pylori were 161 and 198, respectively. Statistical analysis revealed that: (1) At the initial visit, there were no significant differences in the severity and activity of inflammation, atrophy and intestinal metaplasia between the biopsy specimens from the antrum and body respectively in both groups. (2) The severity and activity of inflammation in both the antrum and body were markedly reduced after H. pylori eradication (P = 0.000). (3) Within five years after H. pylori eradication, intestinal metaplasia in the antrum either regressed or had no progression, while the proportion of intestinal metaplasia in the H. pylori-positive group increased significantly (P = 0.032). (4) After H. pylori eradication, the atrophy in both the antrum and body had no significant regression. The P value was 0.223 and 0.402, respectively. CONCLUSIONS: H. pylori eradication results in remarkable reduction in the severity and activity of chronic gastritis, marked resolution of intestinal metaplasia in the antrum. On the other hand, continuous H. pylori infection leads to progressive aggravation of atrophy and intestinal metaplasia.

Adult↗
PubMed2003

[Studies on protein-based identification method of genetically modified capsicum].

The detection system based on protein is a method to evaluate the safety of genetically modified foods (GMF). Using cecropin BD gene in capsicum, a detecting method was set up. It is a system of evaluating the real expressive condition and safety of the foreign target protein of GMF. In this studies, with the preformative technic method, a satisfactory results by making use of hemolymph of immunized pupae of Antheraea pernyi as standard experimental material was achieved, comparing with the realities of the goal protein expressive condition of cecropin D gene in capsicum. The detecting steps were as following: the goal protein from material was extracted roughly, then with CM-Sepharose-FF ion-exchange chromatography twice, the goal protein was purified moderately. The purified product was identified by detecting the anti-bacterial activity, electrophoresis, biological auto-photography of the goal protein and MADDI-TOF mass spectrum. The results showed that the expressive foreign target protein in transgenic capsicum was in accordance with standard protein in the physical and chemical property, anti-bacterial activity and molecular weight. It indicated that expression of the target gene in capsicum is real, it corresponded to expected value. The separation, purification and identification methods of cecropin D were established in the study. By means of the comparative experiments about anti-bacterial activity and molecular weight of anti-bacterial peptide(ABP) from GM-capsicum and hemolymph of immunized pupae of Antheraea pernyi, the identification method of target protein from GM-capsicum was set up. The method is easy to be operated, fast and feasible.

Capsicum↗
PubMed2003

[Gene chip technology and it's application to genetic toxicology].

Gene chip, also called as DNA array, Oligonucleotide Microchip or Oligonucletide array, is a new technology developed in recent years. It can be applied prospectively in life science research, such as gene expression, gene diagnose and gene polymorphism etc. In this paper, the principle, types, procedures and application of gene chip to genetic toxicological research were reviewed.

Humans↗
PubMed2003

[Application of mass spectrometry in the proteome research].

Electrospray ionization(ESI) and matrix-assisted laser desorption ionization(MALDI) are two kinds of newly-developed mass spectrometry techniques. The application of mass spectrometry is described in the proteome research such as MS charting, determination of molecular weight, peptide mass fingerprinting(PMF) and peptide sequence validation. The advantages of mass spectrometry are sensitive, accurate, rapid, high-throughput and automated. They have been proved a powerful technique and can be used as an important method for proteome research.

Mass Spectrometry↗
PubMed2002

Four new families with autosomal dominant partial epilepsy with auditory features: clinical description and linkage to chromosome 10q24.

PURPOSE: Autosomal dominant partial epilepsy with auditory features (ADPEAF) is a rare form of nonprogressive lateral temporal lobe epilepsy characterized by partial seizures with auditory disturbances. The gene predisposing to this syndrome was localized to a 10-cM region on chromosome 10q24. We assessed clinical features and linkage evidence in four newly ascertained families with ADPEAF, to refine the clinical phenotype and confirm the genetic localization. METHODS: We genotyped 41 individuals at seven microsatellite markers spanning the previously defined 10-cM minimal genetic region. We conducted two-point linkage analysis with the ANALYZE computer package, and multipoint parametric and nonparametric linkage analyses as implemented in GENEHUNTER2. RESULTS: In the four families, the number of individuals with idiopathic epilepsy ranged from three to nine. Epilepsy was focal in all of those with idiopathic epilepsy who could be classified. The proportion with auditory symptoms ranged from 67 to 100%. Other ictal symptoms also were reported; of these, sensory symptoms were most common. Linkage analysis showed a maximum 2-point LOD score of 1.86 at (theta=0.0 for marker D10S603, and a maximum multipoint LOD score of 2.93. CONCLUSIONS: These findings provide strong confirmation of linkage of a gene causing ADPEAF to chromosome 10q24. The results suggest that the susceptibility gene has a differential effect on the lateral temporal lobe, thereby producing the characteristic clinical features described here. Molecular studies aimed at the identification of the causative gene are underway.

Adult↗
PubMed2002

[Study on the identification of genomic modified foods].

Nucleotide-based amplification method is an important system for the identification of genomic modified foods (GMF). Roundup Ready Soybeans (Monsanto company), Bt 176 GM maize (Novartis/Ciba-Geigy company) and Cecropin D capsicum was used as material to search for the feasibility of investigating the safety of GMF by PCR method. Primers specific for inserted genes and crop endogenous genes in Roundup Ready Soybeans, Bt 176 maize and Cecropin D capsicum were applied. The discrimination system for GM soybeans, GM maize and GM capsicum from the counterpart of non-GM products and the detection system for correlating marker genes and transgenes are established. The method was easy and fast, and the corresponding results fixed the standard or declared data.

Capsicum↗
PubMed2002

[Virological and serological surveys for H9N2 subtype of influenza A virus in chickens and men in Shenzhen city].

OBJECTIVE: To understand the distribution of influenza A H9N2 virus in chickens and men in Shenzhen area. METHODS: Virus isolation was performed in embryonated hen s eggs with routine method. The antibody to H9N2 virus was detected with micro-hemagglutination inhibition (HI) test, then the results were checked by using the neutralization assay in MDCK cells. RESULTS: Totally 27 strains of influenza A H9N2 virus were isolated from chickens in farm markets in Shenzhen, whereas no H9N2 virus was isolated from men. Approximately 26% of human sera with the HI titers > or =20 to H9N2 virus were detected. However only 7% of chicken sera with the HI titers > or =20 to H9N2 virus were detected. Meanwhile the HI titer and (MGT) of antibody to H9N2 virus in human sera increased with age. It was also found that there was a close relationship between HI antibody titer to H9N2 virus in human sera and occupation. CONCLUSIONS: The distribution of influenza A H9N2 virus in chicken and men in Shenzhen was rather wide. The human H9N2 virus infection probably derived from chicken H9N2 virus.

Animals↗
PubMed2001

Evidence for a language quantitative trait locus on chromosome 7q in multiplex autism families.

Autism is a syndrome characterized by deficits in language and social skills and by repetitive behaviors. We hypothesized that potential quantitative trait loci (QTLs) related to component autism endophenotypes might underlie putative or significant regions of autism linkage. We performed nonparametric multipoint linkage analyses, in 152 families from the Autism Genetic Resource Exchange, focusing on three traits derived from the Autism Diagnostic Interview: "age at first word," "age at first phrase," and a composite measure of "repetitive and stereotyped behavior." Families were genotyped for 335 markers, and multipoint sib pair linkage analyses were conducted. Using nonparametric multipoint linkage analysis, we found the strongest QTL evidence for age at first word on chromosome 7q (nonparametric test statistic [Z] 2.98; P=.001), and subsequent linkage analyses of additional markers and association analyses in the same region supported the initial result (Z=2.85, P=.002; chi(2)=18.84, df 8, P=.016). Moreover, the peak fine-mapping result for repetitive behavior (Z=2.48; P=.007) localized to a region overlapping this language QTL. The putative autism-susceptibility locus on chromosome 7 may be the result of separate QTLs for the language and repetitive or stereotyped behavior deficits that are associated with the disorder.

Autistic Disorder↗
PubMed2001

Genomewide linkage analysis of celiac disease in Finnish families.

Celiac disease (CD), or gluten-sensitive enteropathy, is a common multifactorial disorder resulting from intolerance to cereal prolamins. The only established genetic susceptibility factor is HLA-DQ, which appears to explain only part of the overall genetic risk. We performed a genomewide scan of CD in 60 Finnish families. In addition to strong evidence for linkage to the HLA region at 6p21.3 (Z(max)>5), suggestive evidence for linkage was found for six other chromosomal regions--1p36, 4p15, 5q31, 7q21, 9p21-23, and 16q12. We further analyzed the three most convincing regions--4p15, 5q31, and 7q21--by evaluation of dense marker arrays across each region and by analysis of an additional 38 families. Although multipoint analysis with dense markers provided supportive evidence (multipoint LOD scores 3.25 at 4p15, 1.49 at 5q31, and 1.04 at 7q21) for the initial findings, the additional 38 families did not strengthen evidence for linkage. The role that HLA-DQ plays was studied in more detail by analysis of DQB1 alleles in all 98 families. All but one patient carried one or two HLA-DQ risk alleles, and 65% of HLA-DQ2 carriers were affected. Our study indicates that the HLA region harbors a predominant CD-susceptibility locus in these Finnish families.

Adult↗