Fragility and robustness of self-sustained oscillations in an epidemiological model on small-world networks.

We investigate the susceptible-infected-recovered-susceptible epidemic model, typical of mathematical epidemiology, with the diversity of the durations of infection and recovery of the individuals on small-world networks. Infection spreads from infected to healthy nodes, whose infection and recovery periods denoted by τ and τ, respectively, are either fixed or uniformly distributed around a specified mean. Whenever τ and τ are narrowly distributed around their mean values, the epidemic prevalence in the stationary state is found to reach its maximal level in the typical small-world region.

[Genome-wide search for linkage to attention deficit hyperactivity disorder (ADHD) on the X chromosome].

Attention deficit hyperactivity disorder (ADHD) is the most common childhood-onset behavioral. Boys are more often affected than girls. Family, twin and adoption studies have supported a strong genetic basis.

No association between attention-deficit hyperactivity disorder and catechol-O-methyltransferase gene in Chinese.

Previous studies suggested that the catecholaminergic systems may be involved in the pathogenesis of attention-deficit hyperactivity disorder(ADHD). Since catechel-O-methyltransferase (COMT) is an enzyme involved in the degradation of catecholaminergic neurotransmitters of the dopaminergic and noradrenergic systems,it is possible that COMT may play a role in ADHD. To test this hypothesis, we used two family-based analyses,the transmission disequilibrium test (TDT) and the haplotype-based haplotype relative risk (HHRR), to examine the possible association between COMT gene and DSM-IV-diagnosed ADHD in a Chinese sample consisting of 79 ADHD probands and their parents.

[Expression variation and mutation analysis of exon 9 and 10 in amyloid precursor protein gene in Alzheimer's disease].

To explore the expression differences of exon 9 and 10 in Amyloid Precursor Protein gene(APP9 approximately 10) in Alzheimer's disease,and detect the probable point mutation appeared in cDNA fragment of APP9 approximately 10 in the Shanghai Han people.semi-quantitative competitive RT-PCR technique was performed to detect the expression of APP9 approximately 10 in peripheral lymphocyte, and the Apolipoprotein E gene(ApoE) and Presenilin 1(PS1)gene were genotyped with PCR-RFLP method. We also analyzed the point mutation in APP9 approximately 10 cDNA through the denatured gel electrophoresis.

[A pedigree with myotonic dystrophy: non-CTG, non-CCTG repeat expansion].

Objective: Two genetic loci are associated with the myotonic dystrophy (DM) phenotype: DM1 DMPK on chromosome 19, and DM2 ZNF9 on chromosome 3. The aim of this study was to investigate the molecular genetics of a pedigree with DM.

Methods: In twenty-six individuals from a family with DM, the CTG repeats in DMPK and CCTG repeats in ZNF9were evaluated genetically, using Long Expand trade mark Template polymerase chain reaction (PCR), Southern blotting and genomic scanning.

[Study on gamma-synuclein gene in patients with idiopathic Parkinson's disease].

Objective: To evaluate the relationship between idiopathic Parkinson's disease (PD) and two polymorphisms (C243G and A377T) of the gamma-synuclein gene in a Chinese Han population of Shanghai area.

Methods: Polymorphic genotyping was performed with PCR-RPLP technique. Association analysis was carried out in 145 unrelated idiopathic PD patients and 184 age-matched healthy controls.

[A study on the relation between the apolipoprotein E promoter -427C/T polymorphism and Alzheimer's disease].

Objective: To determine the relation between the apolipoprotein E(apoE) promoter -427C/T polymorphism and Alzheimer's disease (AD) in a Chinese Han population in Shanghai.

Methods: The apoE promoter -427C/T polymorphism in 104 AD cases and 110 healthy subjects was detected using polymerase chain reaction method and restriction fragment length polymorphism genotyping technique. The differences in polymorphic distribution between the two groups were tested, and odds ratio was computed.

[Dopamine beta hydroxylase gene polymorphism and Parkinson's disease].

Objective: To investigate the correlation between the polymorphism of dopamine beta hydroxylase(DBH) gene and the susceptibility of Shanghai Chinese Han population to Parkinson's disease(PD).

Methods: Association study was performed in 144 PD patients and 188 healthy control subjects matched for age, sex and origin. Polymorphism of DBH gene was analyzed with polymerase chain reaction-restriction fragment length polymorphism.