Examining for association between candidate gene polymorphisms in the dopamine pathway and attention-deficit hyperactivity disorder: a family-based study

Attention-deficit hyperactivity disorder (ADHD) is a highly heritable childhood-onset psychiatric condition characterized by developmentally inappropriate inattention, hyperactivity, and impulsiveness. The pathophysiology of ADHD is currently unknown. However, the therapeutic effects of stimulant medication together with findings from animal and neuroimaging studies as well as from several molecular genetic studies of the dopamine receptor D4 gene and dopamine transporter gene have implicated involvement of the dopaminergic system. To test the dopaminergic hypothesis further, we have looked for association between ADHD and alleles of seven dopamine-related candidate genes using a family-based association approach in a sample of 150 children diagnosed with ADHD. We tested polymorphisms in genes encoding three dopamine receptors (DRD3, DRD4, and DRD5) and four dopamine-relevant enzymes: tyrosine hydroxylase [tyrosine hydroxylase (TH)], dopamine beta hydroxylase (DbetaH), catechol-O-methyltransferase (COMT), and monoamine oxidase A (MAOA). We were unable to detect a significant association with any of the polymorphisms genotyped, although there was a trend for preferential transmission of the DRD5 148 bp marker allele and the MAOA 122 bp marker allele. We conclude that none of the alleles we have tested makes a major contribution to ADHD, although much larger samples are required to exclude small effects.

The relationship between life satisfaction, self-consciousness, and the Myers-Briggs type inventory dimensions

The study was an investigation of the relationship between psychological well-being, life satisfaction, self-consciousness, and the four Myers-Briggs Type Indicator dimensions (MBTI; I. B. Myers & M. H. McCaulley, 1985). The participants were 97 college students (79 women and 18 men whose mean age was 31.4 years). All the students were administered four instruments, the Psychological Well-Being Inventory (C. D. Ryff, 1989), the Satisfaction With Life Scale (E. Diener, R. A. Emmons, R. J. Larsen, & S. Griffin, 1985), the Self-Consciousness Scale-Revised (M. F. Scheier & C. S. Carver, 1985), and the MBTI (Form G Self-Scoring). MANOVAs revealed significant differences on three of the four dimensions of the MBTI with extraverts showing higher psychological well-being and life satisfaction and lower self-consciousness than introverts. Intuition types scored higher in psychological well-being and lower in self-consciousness than Sensing types. Judging types scored higher in psychological well-being than Perceiving types. Correlational analyses showed that most dimensions of psychological well-being were negatively related to self-consciousness. The relationship between life satisfaction and personality variables is discussed.

Adolescents' bereavement experiences. Prevalence, association with depressive symptoms, and use of services

The present study set out to estimate the prevalence of bereavement experiences in adolescents, the association between these experiences and depressive symptoms and the attitudes of bereaved young people to professional interventions. The study was based on 1746 adolescents aged between 11 and 16 years from two secondary schools in Northern England. Questionnaire measures of bereavement experiences and depressive symptoms were completed by the adolescents in the classroom. One thousand three hundred and fifty-five (77.6%) reported that at least one of their first-or second-degree relatives or close friends had died. These losses were associated with increased levels of depressive symptoms in comparison with the loss of other relatives or pets. The impact of the loss of someone close depended to an important extent on the young person's perception of how the loss had changed their lives. Most adolescents did not feel the need for professional services. Those who did use these services had higher levels of depressive symptoms, suggesting that service use was likely to have been appropriate.

Feeding behaviour of the aphid Rhopalosiphum padi (Hemiptera: Aphididae) on nitrogen and water-stressed barley (Hordeum vulgare) seedlings

Electrical penetration graphs (EPGs) were used to examine the probing behaviour of adult apterous Rhopalosiphum padi (Linnaeus) on barley seedlings grown under conditions of nitrogen or water stress. Aphids took significantly longer to reach and ingest from sieve elements of nitrogen-deficient seedlings than from nitrogen-sufficient seedlings but there were no such differences between water-stressed or well-watered seedlings. On both nitrogen and water-stressed seedlings the average length of each individual period of salivation into the sieve element was significantly greater compared with their respective unstressed controls.

Safety testing of needle free, jet injection devices to detect contamination with blood and other tissue fluids

Needle free jet injection guns have been used extensively in both veterinary and human health to deliver both vaccine and drugs, but in recent years, concerns have mounted for their potential to transmit blood borne disease agents among consecutive vaccinates. A Ped-O-Jet type jet injection device was used to deliver serial subcutaneous injections of 0.5 mL saline (as a surrogate for vaccine) into calves and pigs, with intervening ejectates collected in vials to represent what the next vaccinate would have received. An enzyme linked immunosorbant assay was developed to detect species specific albumin as a marker for blood, using calibration standards from known dilutions of bovine or porcine blood. Assay sensitivity of 20 pL/mL corresponded to the estimated minimal chimpanzee infectious dose of 10 pL for hepatitis B virus. The methodology and available results for evaluating the safety of jet injector devices are reported.

Depression, suicide and deliberate self-harm in adolescence

The past decade has seen important advances in research into the epidemiology, aetiology and treatment of depression and suicidal behaviour in the young. We are beginning to understand how risk factors combine to precipitate and maintain these problems. There is rarely a linear relationship between causes and outcomes. Rather, the cause is usually a combination of predisposing constitutional factors arising from genetic endowment or earlier experience and precipitating stressful events. These aetiological factors act through biochemical, psychological and social processes to produce the outcome. Progress has also been in the development of a range of effective treatments, such as 'here and now' psychological treatments and antidepressants. All depressed or suicidal young people require careful assessment. Some will require a brief intervention only. Others, however, will require more intensive and lengthy forms of treatment.

Does the definition of ADHD affect heritability?

OBJECTIVE

A twin study design was used to examine the genetic validity of attention-deficit hyperactivity disorder (ADHD)-related phenotypes.

METHOD

Questionnaires covering ADHD symptoms were sent to the families of 2,846 school-age twins. Parent-rated symptoms were obtained for 2,082 twin pairs and teacher-rated symptoms were available for 1,470 twin pairs.

RESULTS

Broadly defined parent-rated, teacher-rated, and "pervasive" (both parent- and teacher-rated) ADHD categories were found to be highly heritable. Significant shared environmental effects were also detected for teacher-rated ADHD. A common genetic factor was found to have a modest influence on both parent- and teacher-rated symptom scores and categories, but additional genetic and environmental influences were also found forteacher-rated ADHD. Consistent with previous findings, ADHD symptom scores were again found to be highly heritable. Maternal contrast effects were found for the Rutter A scale items but could not be detected for the DuPaul ADHD rating scale.

CONCLUSIONS

Broadly defined pervasive ADHD appears to be as heritable as ADHD behaviors defined by maternal reports alone. A common genetic factor influences maternally rated and teacher-rated ADHD but does not account for all of the genetic variance for teacher-rated ADHD. ADHD symptom scores are highly heritable, and maternal contrast effects appear to vary for different measures.

Randomised comparison of the effectiveness and costs of community and hospital based mental health services for children with behavioural disorders

OBJECTIVE

To test the hypothesis that a community based intervention by secondary child and adolescent mental health services would be significantly more effective and less costly than a hospital based intervention.

DESIGN

Open study with two randomised parallel groups.

SETTING

Two health districts in the north of England.

PARTICIPANTS

Parents of 3 to 10 year old children with behavioural disorder who had been referred to child and adolescent mental health services.

INTERVENTION

Parental education groups.

MAIN OUTCOME MEASURES

Parents' and teachers' reports of the child's behaviour, parental depression, parental criticism of the child, impact of the child's behaviour on the family.

RESULTS

141 subjects were randomised to community (n=72) or hospital (n=69) treatment. Primary outcome data were obtained on 115 (82%) cases a year later. Intention to treat analyses showed no significant differences between the community and hospital based groups on any of the outcome measures, or on costs. Parental depression was common and predicted the child's outcome.

CONCLUSIONS

Location of child mental health services may be less important than the range of services that they provide, which should include effective treatment for parents' mental health problems.

A family-based and case-control association study of the dopamine D4 receptor gene and dopamine transporter gene in attention deficit hyperactivity disorder

Attention deficit hyperactivity disorder (ADHD) is a highly heritable psychiatric condition of early childhood onset characterised by marked inattention, hyperactivity and impulsiveness. Molecular genetic investigations of ADHD have found positive associations with the 480-bp allele of a VNTR situated in the 3' untranslated region of DAT1 and allele 7 of a VNTR in exon 3 of DRD4. A number of independent studies have attempted to replicate these findings but the results have been inconsistent. We used both family-based and case control approaches to examine these polymorphisms in a sample of 137 children diagnosed with ICD-10, DSM-IV or DSM-III-R ADHD. We found no evidence of association with the DAT1 polymorphism, despite a sample size that has up to 80% power to detect a previously reported effect size. We observed a significant increase in the DRD4 7 repeat allele amongst ADHD probands (21.7%) and their parents (18.9% in mothers, 22.3% in fathers), compared to ethnically matched controls (12.8%). However TDT analysis showed no preferential transmission of allele 7 to ADHD probands.

Direct detection of infectious HIV-1 in blood using a centrifugation-indicator cell assay

Plasma HIV RNA is a useful surrogate marker for predicting HIV-1 disease progression in infected individuals but provides no information regarding the infectious viral titer. Traditional assays of infectious HIV-1 are, however, time consuming, insensitive, use non-standardized reagents and are subject to selection bias introduced by prolonged cultivation. In this pilot study infectious HIV-1 was detected directly in patient plasma using the indicator line HeLa-CD4-CCR5-LTR/beta-gal in a centrifugation-culture method. Replication competent HIV-1 was identified within 2 days of tissue culture inoculation in six (26%) of 23 plasma specimens. The capability of a new cell line, MT4-CCR5-tat, to amplify plasma HIV-1 was also tested. HIV was cultivated from ten (71%) of 14 specimens using MT4-CCR5-tat cells before titering the virus with the indicator cell assay. Using these stable cell lines in refined versions of this assay it may be feasible to develop rapid, simple methods for titering infectious plasma HIV-1 and for testing the susceptibility of the virus to antiretroviral drugs.

Developing child mental health services in developing countries

There is an urgent need to pay attention to the mental health of children in developing countries. Professionals confronted with this task face a number of challenges. Services have to be planned in a rational way, keeping in mind the needs of local populations. These needs will often exceed the available resources, and it will be necessary to set priorities. Feasible and cost-effective models of service delivery then have to be developed to meet these needs. This annotation provides a framework within which mental health needs of children can be assessed, priorities established, and services organised. This is illustrated with examples of relevant activities undertaken in low-income developing countries over the last two decades.

Global networking for assessment of impacts of global change on plant pests

Global change encompasses changes in atmospheric composition, climate and climate variability, and land cover and land use. The occurrence of these changes and their interactive effects on biological systems are worldwide; thus, an effective global change research and impact assessment program must be based on international and interdisciplinary research and communication. With this in mind, several collaborative research networks with a focus on global change have been established in the biological sciences. They include the Global Change and Terrestrial Ecosystems (GCTE) Core Project of the International Geosphere-Biosphere Programme (IGBP) which aims to predict the effects of global change on terrestrial ecosystems, including agriculture and production forestry. Because of the importance of plant pests (arthropods, microbial pathogens, weeds) as yield-reducing factors in agriculture and as early indicators of global change, GCTE initiated a network Activity on "Global Change Impacts on Pests, Diseases and Weeds" with the overall goal of developing a predictive capability for impact assessment and adaptation. The network's specific objectives, contributing research projects, initial results and future challenges are discussed.

Design of the blockade of the glycoprotein IIb/IIIa receptor to avoid vascular occlusion (BRAVO) trial

BACKGROUND

Platelets play a key role in the pathogenesis of atherosclerosis, thrombosis, and acute coronary and cerebrovascular syndromes. Inhibition of platelet function by acetylsalicylic acid (aspirin) has been shown to reduce the incidence atherothrombotic events in patients with coronary, cerebrovascular, or peripheral vascular disease. Thienopyridine agents, however, including ticlopidine and clopidogrel, inhibit the adenosine diphosphate receptor and have modestly superior effects compared with aspirin on reduction of death, myocardial infarction, and stroke among a broad group of patients with vascular disease. More effective antithrombotic agents are still required to treat patients at high risk for recurrent vascular events.

METHODS

Lotrafiban, a selective, nonpeptide antagonist of the human platelet fibrinogen receptor (glycoprotein [GP] IIb/IIIa [alphaIIb/beta3 integrin]), blocks the binding of fibrinogen to the GP IIb/IIIa receptor, which is the final common pathway of platelet aggregation. Lotrafiban at doses of up to 50 mg twice daily was well-tolerated in a 12-week, double-blind, placebo-controlled, dose-ranging study in patients with recent myocardial infarction, unstable angina, transient ischemic attack, or stroke when added to aspirin therapy. On the basis of these results, a dosing regimen was selected for the phase III Blockage of the Glycoprotein IIb/IIIa Receptor to Avoid Vascular Occlusion (BRAVO) trial based on pharmacodynamics and drug tolerability. In the pivotal BRAVO study, lotrafiban therapy is being evaluated in patients who have had a recent myocardial infarction, unstable angina, transient ischemic attack, or ischemic stroke, or who present at any time after a diagnosis of peripheral vascular disease combined with either cardiovascular or cerebrovascular disease.

RESULTS

The efficacy evaluation will be based on a composite end point of clinical events (death by any cause, myocardial infarction, stroke, recurrent ischemia requiring hospitalization, or urgent ischemia-driven revascularization). The target enrollment is 9200 patients worldwide. Approximately 700 centers will participate and will be distributed within 30 countries across North America, Europe, Australia, and Asia.

Complementary approaches to the assessment of personality disorder. The Personality Assessment Schedule and Adult Personality Functioning Assessment compared

BACKGROUND

Current concepts and measures of personality disorder are in many respects unsatisfactory.

AIMS

To establish agreement between two contrasting measures of personality disorder, and to compare subject-informant agreement on each. To examine the extent to which trait abnormality can be separated from interpersonal and social role dysfunction.

METHOD

Fifty-six subjects and their closest informants were interviewed and rated independently. Personality functioning was assessed using a modified Personality Assessment Schedule (M-PAS), and the Adult Personality Functioning Assessment (APFA).

RESULTS

Subject-informant agreement on the M-PAS was moderately good, and agreement between the M-PAS and the APFA, across and within subjects and informants, was comparable to that for the M-PAS. This was equally the case when M-PAS trait plus impairment scores and trait abnormality scores were used.

CONCLUSIONS

The M-PAS and the APFA are probably assessing similar constructs. Trait abnormalities occur predominantly in an interpersonal context and could be assessed within that context.

Deliberate self-poisoning in adolescence: why does a brief family intervention work in some cases and not others?

In a randomized trial of a brief family intervention with adolescents who had deliberately poisoned themselves, we have previously reported that, within the group of patients who did not have major depression, the family intervention was significantly superior to routine care in reducing suicidal thinking. The present paper examined whether efficacy was related to changes in family functioning or other possible mediating variables. Potential mediators included family functioning, hopelessness, depression, adolescent problem-solving and compliance with treatment. The efficacy of the family intervention in reducing suicidal ideation within the non-depressed sub-group was probably not mediated by changes in these variables. The implications of this finding are discussed.

The MacArthur Three-City Outcome Study: evaluating multi-informant measures of young children's symptomatology

OBJECTIVE

Three sites collaborated to evaluate the reliability and validity of 2 measures, developed in tandem to assess symptomatology and impairment in 4- to 8-year-old children: the Berkeley Puppet Interview Symptomatology Scales (BPI-S) and the Health and Behavior Questionnaire (HBQ).

METHOD

In this case-control study, mothers, teachers, and children reported on multiple dimensions of children's mental health for 120 children (67 community and 53 clinic-referred children).

RESULTS

The BPI-S and the parent and teacher versions of the HBQ demonstrated strong test-retest reliability and discriminant validity on a majority of symptom scales. Medium to strong effect sizes (Cohen d) indicated that children in the clinic-referred group were viewed by all 3 informants as experiencing significantly higher levels of symptomatology than nonreferred, community children.

CONCLUSION

The availability of a set of multi-informant instruments that are psychometrically sound, developed in tandem, and developmentally appropriate for young children will enhance researchers' ability to investigate and understand symptomatology or the emergence of symptomatology in middle childhood.

Minimal myocardial damage during coronary intervention is associated with impaired outcome

AIMS

Studies on the glycoprotein IIb-IIIa receptor blocker abciximab in patients undergoing percutaneous coronary intervention consistently show a reduction in procedure-related myocardial infarction. Some such infarcts are characterized by elevated creatine kinase or creatine kinase-MB, without apparent clinical symptoms. The clinical relevance of such 'creatine kinase leaks' has been questioned. Therefore we investigated the relationship between post-procedural creatine kinase-MB elevation and outcome at the 6 month follow-up.

METHODS AND RESULTS

Creatine kinase-MB, or total creatine kinase values were analysed in 5025 out of 6156 patients enrolled in the CAPTURE, EPIC and EPILOG studies. A consistent gradual increase in 6 month mortality was observed as creatine kinase-MB or creatine kinase levels increased: 1.1%, 2.1%, 1.8%, 3. 6% and 6.7% for creatine-MB or creatine ratios (relative to upper limit of normal) <1, 1-3, 3-5, 5-10 and >/=10, respectively. Also the incidence of death or (recurrent) myocardial infarction was related to creatine kinase-MB or creatine kinase ratios. Subsequent revascularization was not related to periprocedural myocardial infarction. By multivariable analysis, correcting for clinical and angiographic characteristics, mortality at 6 months was related to the enzyme (creatine kinase, creatine kinase-MB) ratio, a history of heart failure and age. The combined end-point of death and myocardial infarction was also related to these factors, as well as to a history of bypass surgery and unstable angina.

CONCLUSION

Modest elevation of cardiac enzymes (creatine kinase-MB, creatine kinase) after percutaneous coronary intervention is associated with an increased risk of mortality and reinfarction during the 6 month follow-up. Measures to reduce such periprocedural infarcts are warranted.

Reliability of the Salford Needs Assessment Schedule for Adolescents

BACKGROUND

For adolescents, there is no specific needs assessment instrument that assesses significant problems that can benefit from specified interventions. A new instrument (S.NASA) was developed by incorporating and adapting three well established adult needs assessment instruments. The S.NASA covers 21 areas of functioning including social, psychiatric, educational and life skills.

METHOD

Client and carer interviews were conducted by different researchers. A week later the interviews were repeated using a crossover design. Significant (cardinal) problems were generated from the clinical interviews using a pre-defined algorithm. Final need status (three categories) was made by clinicians assessing the cardinal problems against defined interventions. The interventions were generated from discussions with clinicians and a survey of appropriate professionals working with adolescents. RESULTS. Pre-piloting led to the final version being administered to 40 adolescents from secure units, forensic psychiatric and adolescent psychiatric services. There were 25 males and 15 females, mean age 15.5 years. Overall there were moderate to good inter-rater and test-retest reliability coefficients, the test-retest reliability coefficients for the total scores on the needs assessment interviews ranged from 0.73 to 0.85. Consensual and face validity was good, the adolescents and staff finding the instrument useful and helpful.

CONCLUSIONS

This new needs assessment instrument shows acceptable psychometric properties. It should be of use in research projects assessing the needs and the provision of services for adolescents with complex and chronic problems.

In vivo transduction of mouse epidermis with recombinant retroviral vectors: implications for cutaneous gene therapy

Gene-based therapies may provide a way to treat inherited skin disorders but current approaches suffer serious limitations. The surgical procedures required to transplant ex vivo modified keratinocytes are likely to result in scarring and contracture, thereby limiting the area that can be treated. In addition, none of the methods currently available for in vivo gene transfer to epidermis leads to long-term transgene expression. The goal of this study was to develop a means for in vivo gene transfer to epidermis that would result in long-term transgene expression. We report here the first successful in vivo gene transfer that results in sustained transgene expression in epidermis. Hyperplastic mouse skin was transduced by direct injection of VSV-G pseudotyped retroviral vectors encoding the LacZ reporter gene. In mice tolerant to beta-galactosidase (beta-gal), transgene expression was noted in hair follicles and interfollicular epidermis for the duration of the experiment (16 weeks after transduction). Based on the kinetics of epidermal turnover in mouse skin, expression for this length of time strongly suggests stem cell transduction. In immunocompetent mice intolerant to beta-gal, transgene expression was lost by 3 weeks after transduction, concurrent with the onset of host immune responses to the transgene product.

Genetic basis of attention deficit and hyperactivity

BACKGROUND

Hyperkinetic disorder or attention-deficit hyperactivity disorder (ADHD) is an important clinical condition.

AIMS

The research evidence for a genetic contribution to ADHD is reviewed.

METHOD

Measurement of the phenotype, the extent to which attention deficit and hyperactivity are heritable and molecular genetic findings are discussed. Future research directions are also considered.

RESULTS

ADHD is a familial disorder. Available adoption evidence suggests genetic influences are important. Twin studies have primarily focused on trait measures which have consistently been found to be highly heritable Molecular genetic studies of clinical disorder so far have suggested the involvement of the dopamine DRD-4 receptor gene and dopamine transporter gene (DAT1). However, these findings await further replication.

CONCLUSIONS

Advances in psychiatric genetics and current research interest in the genetics of ADHD should improve our understanding of aetiological factors and have an impact on treatment.