Biomedical subjects

Karen Sheehan

Publications and source records attributed to Karen Sheehan.

6 recordsLinked to original sources

PubMed2006

No association between TPH2 gene polymorphisms and ADHD in a UK sample.

Tryptophan Hydroxylase 2 (TPH2) is the rate-limiting enzyme in the biosynthesis of serotonin which is exclusively expressed in the brain. Recent molecular studies reported significant association between markers mapped to TPH2 and psychiatric conditions including ADHD. We have examined four single nucleotide polymorphisms (SNPs) two of which (rs1843809, rs1386493) were reported to associate with ADHD in an Irish ADHD sample. Transmission disequilibrium analysis revealed no significant association between any of these markers and ADHD. Dividing by the sex of the transmitting parent has also failed to replicate the previously reported paternal over-transmission of the associated alleles to ADHD probands. A larger sample size will be required to clarify if TPH2 alleles are or are not associated with ADHD.

Adolescent↗

PubMed2006

Injury in the first year of life: risk factors and solutions for high-risk families.

BACKGROUND: Injury is one of the leading causes of death for infants younger than 1 year of age. We investigated potential contributing factors for injury among children born to high-risk families. METHODS: The Fragile Families and Child Wellbeing Study is a longitudinal cohort of approximately 5000 children from mostly unwed parents across the United States. Data from interviews with mothers conducted shortly after birth and follow-up surveys at 1 year were used for this analysis. Injuries sustained in the first year of life that required medical attention were studied. Multivariate regression analysis was used to identify independent risk factors for injury in this population. RESULTS: A total of 13.7% of mothers reported that their child had sustained an injury in the first year of life. We identified 17 potential maternal, paternal, and environmental risk factors for injury, including socioeconomic, mental health, relationship violence, criminal justice system involvement, and substance abuse challenges. Multivariate regression analyses revealed two significant independent risk factors, maternal alcohol use (odds ratio 2.15, P = 0.044) and mother spanking child in the previous month (odds ration 2.32, P = 0.027). CONCLUSIONS: Among this higher-risk group, injury in the first year of life is more than twice the national incidence. Predisposing factors to injury often are complex and interrelated, but with focused education and prevention efforts, including discussions of maternal alcohol use and attitudes toward physical discipline, we may decrease the burden of infant injury in this vulnerable population.

Alcohol Drinking↗

PubMed2006

Paediatric cardiac nursing education: a national collaboration.

Educational courses for staff working in paediatric specialties may not be financially viable because of the small numbers involved and the difficulties that potential students have in getting released from their units. The UK Paediatric Cardiac Nurses Association worked with other groups to explore the feasibility of a national multi-professional paediatric cardiac education pathway. Three options were identified, including the continuation of local in-house provision with its associated variation in standards. The relative benefits and resource implications of each option were explored and approaches made to educational institutions for support in developing the pathway. A university with an established reputation for e-learning undertook this development and a post graduate certificate in Paediatric Cardiothoracic Practice will soon be available.

Cardiology↗

PubMed2005

Preferential transmission of paternal alleles at risk genes in attention-deficit/hyperactivity disorder.

Family, twin, and adoption studies have demonstrated a significant genetic contribution to the etiology of attention-deficit/hyperactivity disorder (ADHD). Pharmacological, neuroimaging, and animal-model findings suggest imbalances in monoaminergic (dopaminergic, serotonergic, and noradrenergic) neurotransmission in ADHD. We have examined monoaminergic candidate genes for possible genetic association with ADHD in the Irish population, focusing particularly on genes of the dopaminergic and serotonergic systems. We have observed that several of these genes are associated with ADHD, including DAT1, DBH, DRD4, DRD5, and 5HT1B. Here, we present what appears to be a systematic overtransmission of paternal alleles at candidate genes associated with ADHD. For the nine genes included in the analysis, the overall odds ratio for paternal transmission was 2, compared with 1.3 for maternal transmission (paternal vs. maternal chi 2=9.6; P=.0019). Transmission to females, from either parent, was significantly stronger than to males. Possible reasons for this preferential transmission include imprinting and ascertainment bias, although results of further analyses show that the latter is unlikely.

Alleles↗

PubMed2005

Association analysis of the monoamine oxidase A and B genes with attention deficit hyperactivity disorder (ADHD) in an Irish sample: preferential transmission of the MAO-A 941G allele to affected children.

Pharmacological and genetic studies suggest the importance of the dopaminergic, serotonergic, and noradrenergic systems in the pathogenesis of attention deficit hyperactivity disorder (ADHD). Monoamine oxidases A and B (MAO-A and MAO-B) degrade biogenic amines such as dopamine and serotonin and thereby control the levels of these neurotransmitters in the central nervous system. We examined four polymorphisms in the MAO-A gene (30 bp promoter VNTR, CA microsatellite in intron 2, 941G/T SNP in exon 8, and A/G SNP in intron 12) as well as two markers in the MAO-B gene (CA microsatellite in intron 2 and T/C SNP in intron 13) for association with ADHD in an Irish sample of 179 nuclear families. TDT analysis of the examined MAO-A markers revealed a significant association of the more active MAO-A 941G allele with the disorder (chi2 = 5.1, P = 0.03, OR = 1.7). In addition, haplotype analysis revealed a significantly increased transmission of a haplotype consisting of the shorter allele of the promoter VNTR (allele 1), the 6-repeat allele of the CA microsatellite and the G-allele of the 941G/T SNP (famhap global statistic 34.54, P = 0.01) to ADHD cases. No significant distortion in the number of transmitted alleles was observed between the two examined MAO-B polymorphisms and ADHD. These findings suggest the importance of the 941G/T MAO-A polymorphism in the development of ADHD at least in the Irish population.

Adult↗

PubMed2004

Urban children's perceptions of violence.

OBJECTIVE: To determine how preadolescent urban children conceptualize and experience violence in their lives. DESIGN: This qualitative study reports the results of focus groups designed to examine perceptions of violence among preadolescent urban children. Program directors were trained to conduct the sessions using a semistructured script. All groups were audiotaped or videotaped. The summaries were analyzed for recurring themes. SETTING: A community-based visual arts program for children designed to be a secondary violence-prevention program. PARTICIPANTS: There were 12 focus groups of volunteer participants. Each consisted of 3 to 6 children aged 8 to 12 years, separated by sex and age. Fifty children participated: 27 boys and 23 girls. RESULTS: These children defined violence in a broader way than most adults would. Not only did the children identify shootings and stabbings as examples of violence, but they also considered violence to be any act that might hurt someone's feelings (such as cheating and lying) or any act accompanying violence (such as cursing and yelling). The boys and girls were very similar in their views except regarding the issue of intimate-partner violence. The girls were almost universally concerned about this issue, but the boys seemed noticeably unaware that intimate-partner violence was considered a form of violence. Most children felt safe at home, and almost no child felt safe at school. They looked to trusted adults to keep them safe. CONCLUSIONS: Future investigators measuring the effect of violence-prevention activities on preteen children should be aware that their definition of violence may differ from that of young children and should be cognizant of potential sex differences, especially around the topic of intimate-partner violence. Those designing violence-prevention programs for children should consider engaging adult family members as well because children usually turn to them for safety.

Attitude↗