Effects of ecstasy on cooperative behaviour and perception of trustworthiness: a naturalistic study

BACKGROUND

Acute recreational use of 3,4-methylenedioxymethamphetamine (MDMA; 'ecstasy') can promote pro-social effects which may alter interpersonal perceptions.

AIMS

To explore such effects, this study investigated whether acute recreational use of ecstasy was associated with changes in individual perception of trustworthiness of people's faces and co-operative behaviours.

METHOD

An independent group, repeated measures design was used in which 17 ecstasy users were tested on the night of drug use (day 0) and again three days later (day 3); 22 controls were tested on parallel days. On each day, participants rated the trustworthiness of 66 faces, carried out three co-operative behaviour tasks (public good; dictator; ultimatum game) and completed mood self-ratings.

RESULTS

Acute ecstasy use was associated with increased face trustworthiness ratings and increased cooperative behaviour on the dictator and ultimatum games; on day 3 there were no group differences on any task. Self-ratings showed the standard acute ecstasy effects (euphoria, energy, jaw clenching) with negative effects (less empathy, compassion, more distrust, hostility) emerging on day 3.

CONCLUSIONS

Our findings of increased perceived trustworthiness and co-operative behaviours following use of ecstasy suggest that a single dose of the drug enhances aspects of empathy. This may in turn contribute to its popularity as a recreational drug and potentially to its enhancement of the therapeutic alliance in psychotherapy.

Learning rate and temperament in a high predation risk environment

Living in challenging environments can influence the behavior of animals in a number of ways. For instance, populations of prey fish that experience frequent, nonlethal interactions with predators have a high proportion of individuals that express greater reaction to risk and increased activity and exploration—collectively known as temperament traits. Temperament traits are often correlated, such that individuals that are risk-prone also tend to be active and explore more. Spatial learning, which requires the integration of many sensory cues, has also been shown to vary in fish exposed to different levels of predation threat. Fish from areas of low predation risk learn to solve spatial tasks faster than fish from high predation areas. However, it is not yet known whether simpler forms of learning, such as learning associations between two events, are similarly influenced. Simple forms of associative learning are likely to be affected by temperament because a willingness to approach and explore novel situations could provide animals with a learning advantage. However, it is possible that routine-forming and inflexible traits associated with risk-prone and increased exploratory behavior may act in the opposite way and make risk-prone individuals poorer at learning associations. To investigate this, we measured temperament in Panamanian bishop fish (Brachyrhaphis episcopi) sampled from a site known to contain many predators. The B. episcopi were then tested with an associative learning task. Within this population, fish that explored more were faster at learning a cue that predicted access to food, indicating a link between temperament and basic learning abilities.

T-ray Imaging and Tomography

We demonstrate two algorithms used forreconstructing the target's structure basedon the diffracted pulses and additionallyshow that a three-dimensional target can bereconstructed using the broadband pulsesand a Fresnel lens by virtue of itsfrequency dependent focal length. Oneadvantage of T-ray imaging is the abilityto measure the far-infrared spectralresponse of the target. To highlight theimportance of this spectral information, wedemonstrate T-ray classification imagingwith different biological samples using asimple classification algorithm and twodimensional T-ray spectroscopic images.

Genetic load is associated with hypothalamic-pituitary-adrenal axis dysregulation in macaques

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis pathway is associated with several neuropsychiatric disorders, including post-traumatic stress disorder (PTSD), major depressive disorder (MDD), schizophrenia and alcohol abuse. Studies have demonstrated an association between HPA axis dysfunction and gene variants within the cortisol, serotonin and opioid signaling pathways. We characterized polymorphisms in genes linked to these three neurotransmitter pathways and tested their potential interactions with HPA axis activity, as measured by dexamethasone (DEX) suppression response. We determined the percent DEX suppression of adrenocorticotropic hormone (ACTH) and cortisol in 62 unrelated, male rhesus macaques. While DEX suppression of cortisol was robust amongst 87% of the subjects, ACTH suppression levels were broadly distributed from -21% to 66%. Thirty-seven monkeys from the high and low ends of the ACTH suppression distribution (18 'high' and 19 'low' animals) were genotyped at selected polymorphisms in five unlinked genes (rhCRH, rhTPH2, rhMAOA, rhSLC6A4 and rhOPRM). Associations were identified between three variants (rhCRH-2610C>T, rhTPH2 2051A>C and rh5-HTTLPR) and level of DEX suppression of ACTH. In addition, a significant additive effect of the 'risk' genotypes from these three loci was detected, with an increasing number of 'risk' genotypes associated with a blunted ACTH response (P = 0.0009). These findings suggest that assessment of multiple risk alleles in serotonin and cortisol signaling pathway genes may better predict risk for HPA axis dysregulation and associated psychiatric disorders than the evaluation of single gene variants alone.

Childcare use and inequalities in breastfeeding: findings from the UK Millennium Cohort Study

BACKGROUND

UK breastfeeding rates are low and socially distributed. Childcare provides a potential setting for breastfeeding promotion. However, little is known about the association between childcare and breastfeeding in different socio-economic groups.

METHODS

Using data from a contemporary UK cohort of infants (n=18,050) the authors calculated RR for breastfeeding for at least 4 months according to informal childcare (care by friends, grandparents, other relatives, etc) and formal childcare (eg, nurseries, crèches), both lasting at least 10 h a week and commencing before the age of 4 months, compared to being cared for 'only by a parent' (this includes childcare for less than 10 h a week), overall and by socio-economic group.

RESULTS

Compared to being looked after only by a parent, informal (RR 0.51 (95% CI 0.43 to 0.59)) and formal (0.84 (0.72 to 0.99)) childcare was associated with a reduced likelihood of breastfeeding. For informal childcare, both part-time and full-time care was associated with a reduced risk of breastfeeding, whereas for formal care, only full-time formal childcare was associated with a reduced likelihood of breastfeeding. The reduced likelihood of breastfeeding in informal childcare was similar across all socio-economic groups, whereas for formal childcare the reduced likelihood was only seen for mothers from managerial and professional backgrounds (0.76 (0.62 to 0.94)), those who had a degree (0.71 (0.58 to 0.86)) and couple families (0.79 (0.66 to 0.94)). In contrast, lone mothers were more likely to breastfeed if their infant was cared for in formal childcare (1.65 (1.04 to 2.63)).

CONCLUSIONS

Informal childcare was associated with a reduced likelihood of breastfeeding for all groups of mothers. Formal childcare arrangements were only associated with a reduced likelihood of breastfeeding if used full-time by more advantaged families.

Does the home environment influence inequalities in unintentional injury in early childhood? Findings from the UK Millennium Cohort Study

BACKGROUND

Children from disadvantaged backgrounds are more likely to experience unintentional injuries and poor home environments. The aim of this study was to explore the home environment as a potential mediator between socioeconomic circumstances and unintentional injuries, in the UK Millennium Cohort Study (n=14 378).

METHODS

RRs and 95% CIs for being injured in the home between age 9 months and 3 years were estimated according to four measures of socioeconomic circumstances: social class, maternal education, lone parenthood status and tenure. Proxy indicators of housing quality (build type, storey, garden access, rooms per capita, central heating and presence of damp) and safety equipment use (use of fireguards, safety gates, electric socket covers and smoke alarms) were then controlled for in order to observe potential mediation.

RESULTS

Children from routine and manual backgrounds were more likely to be injured than those from managerial and professional backgrounds (RR=1.33, 95% CI 1.21 to 1.47), as were children of lone parents (compared with couple families) (RR=1.23, 95% CI 1.12 to 1.36), those whose mothers had no educational qualifications (compared with a degree) (RR=1.42, 95% CI 1.24 to 1.63) and those living in socially rented accommodation (compared with owned/mortgaged homes) (RR=1.35, 95% CI 1.24 to 1.46). However, controlling for the indicators of housing quality and safety equipment use did not alter the elevated risk of injury experienced by children from less advantaged backgrounds.

CONCLUSIONS

In this contemporary UK cohort, proxy indicators of the home environment did not appear to explain socioeconomic inequalities in injuries. Research exploring alternative explanations for inequalities in injuries could help contribute to the design or adaptation of policies to reduce them.

Resources for genetic management and genomics research on non-human primates at the National Primate Research Centers (NPRCs)

The National Primate Research Centers (NPRCs) established Working Groups (WGs) for developing resources and mechanisms to facilitate collaborations among non-human primate (NHP) researchers. Here we report the progress of the Genome Banking and the Genetics and Genomics WGs in developing resources to advance the exchange, analysis and comparison of NHP genetic and genomic data across the NPRCs. The Genome Banking WG has established a National NHP DNA bank comprising 1250 DNA samples from unrelated animals and family trios from the 10 NHP species housed within the NPRC system. The Genetics and Genomics WG is developing SNP arrays that will provide a uniform, highly informative, efficient and low-cost method for rhesus and long-tailed macaque genotyping across the eight NPRCs. This WG is also establishing a Biomedical Informatics Research Network-based portal for shared bioinformatics resources including vital statistics, genotype and population data and information on the National NHP DNA bank.

Does childcare influence socioeconomic inequalities in unintentional injury? Findings from the UK Millennium Cohort Study

BACKGROUND

In recent decades the proportion of infants and young children being cared for in childcare has increased. Little is known about the impact that non-parental care has on childhood unintentional injury and whether this varies by socioeconomic group.

METHODS

Using data from a contemporary UK cohort of children at age 9 months (N = 18 114) and 3 years (N = 13 718), Poisson regression was used to explore the association between childcare type (parental, informal, formal) and the risk of unintentional injury, overall and by socioeconomic group.

RESULTS

At age 9 months there was no overall association between childcare and injury. However, when stratifying the analyses, infants from higher socioeconomic groups were less likely to be injured if they were cared for in formal childcare (compared with being cared for only by a parent), whereas those from lower social groups were more likely to be injured. At age 3 years informal childcare was associated with an increased risk of injury overall; in the stratified analyses this increased risk occurred only in less affluent groups. Formal childcare was no longer associated with injury at age 3 in any strata.

CONCLUSIONS

Previous findings have shown that childcare can have a positive influence on childhood injury; however, a recent Unicef report highlighted that a lack of access to high-quality childcare could lead to a widening of inequalities. Our analyses indicate that childcare does have the potential to widen inequalities in injury; further research is required to understand why childcare has a differential impact on unintentional injury and how this might be prevented.

Evidence for the receipt of DNA damage stimuli by PML nuclear domains

Promyelocytic leukaemia nuclear domains (PML-NDs) comprise a shell of PML protein and many labile cargo proteins. The nature of their cargo, their juxtaposition to foci of damaged DNA following ionizing radiation (IR), and the altered DNA damage responses in PML null cells all implicate PML-NDs in the DNA damage response. In this work, the propensity of PML-NDs to increase in number and decrease in size following IR has been studied. Serial quantitative studies of endogenous PML-NDs prove that the PML-ND response to IR is not the result of the asymmetry in cell cycle distribution that can follow IR, but reflects more directly the process of DNA damage. The response is swift, sensitive (evident after 1 Gy), and potentially reversible in untransformed fibroblasts. In these cells and in HCT116 colon cancer cells, failure to restore PML-ND number within 24 h correlates with later loss of growth potential--in fibroblasts, through prolonged cell cycle arrest and in HCT116 cells, through apoptosis. Failure to express an intact ATM/CHK2 DNA damage signalling pathway in either cell type leads to a delay in the PML-ND response to IR. Conversely, cell cycle progression following IR in cells that detect damaged DNA accelerates PML-ND reorganization. Collectively, these data show that the increase in PML-ND number seen after irradiation is, in part, triggered by the receipt of the DNA damage stimulus. The senescent cell state is also associated with chronic DNA damage and Hayflick-limited fibroblasts were found to express nuclei with elevated numbers of PML-NDs before IR that remained unresponsive to IR. Though the underlying reasons for damage-induced PML alteration remain obscure, it is noteworthy that significant numbers of PML-NDs juxtapose with ionizing radiation-induced foci after IR. The co-regulation of these structures may necessitate the stereotyped increases in PML-ND number following damage.

Enhanced T-ray signal classification using wavelet preprocessing

This study demonstrates the application of one-dimensional discrete wavelet transforms in the classification of T-ray pulsed signals. Fast Fourier transforms (FFTs) are used as a feature extraction tool and a Mahalanobis distance classifier is employed for classification. Soft threshold wavelet shrinkage de-noising is used and plays an important role in de-noising and reconstruction of T-ray pulsed signals. An iterative algorithm is applied to obtain three optimal frequency components and to achieve preferred classification performance.

Endoscopic ultrasonography in the diagnosis and staging of neoplasms of the head and neck

BACKGROUND AND STUDY AIMS

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a minimally invasive and highly accurate method of detecting mediastinal lymph-node metastases in gastrointestinal and lung cancer. Little information is available regarding the use of EUS-FNA to stage tumors in the head and neck region. This study reports experience with EUS in the diagnosis and staging of these tumors and their mediastinal spread.

PATIENTS AND METHODS

The records of patients who underwent EUS for diagnosis and/or staging of head and neck tumors were reviewed. Referral criteria were suspected invasion of the esophagus by a lower-neck mass on cervical computed tomography (CT) or magnetic resonance imaging (MRI), or mediastinal lymphadenopathy > 10 mm on a chest CT.

RESULTS

Thirty-two patients (23 men, nine women; mean age 65 years, range 44 - 80) were referred and underwent 35 EUS examinations. In one patient, EUS was not possible due to a benign esophageal stricture. In 17 patients with suspected esophageal invasion on CT scans, EUS demonstrated invasion of the esophagus in four cases and of the pleura in one; 12 tumors showed no visible invasion of adjacent structures. The other 17 examinations were carried out for suspected mediastinal metastatic disease. In eight cases, EUS-FNA confirmed metastatic disease, whereas only benign changes were shown in the other nine cases. EUS-FNA also provided the first tissue diagnosis in two primary tumors and identified malignancy in one patient with no CT suspicion of positive mediastinal lymph nodes. EUS avoided the need for more invasive investigations in all patients with mediastinal lymphadenopathy, and it changed the management in 12 of the 17 patients (71 %) with suspected esophageal invasion and in eight of the 17 patients (47 %) with suspected mediastinal disease.

CONCLUSIONS

EUS with FNA provides a viable approach to the diagnosis and staging of tumors in the head and neck region when there is a suggestion of esophageal invasion on CT or MRI, or enlarged mediastinal lymph nodes. EUS with FNA may avoid the need for mediastinoscopy or other more invasive techniques for staging of these neoplasms.

New algorithms for multi-class cancer diagnosis using tumor gene expression signatures

MOTIVATION

The increasing use of DNA microarray-based tumor gene expression profiles for cancer diagnosis requires mathematical methods with high accuracy for solving clustering, feature selection and classification problems of gene expression data.

RESULTS

New algorithms are developed for solving clustering, feature selection and classification problems of gene expression data. The clustering algorithm is based on optimization techniques and allows the calculation of clusters step-by-step. This approach allows us to find as many clusters as a data set contains with respect to some tolerance. Feature selection is crucial for a gene expression database. Our feature selection algorithm is based on calculating overlaps of different genes. The database used, contains over 16 000 genes and this number is considerably reduced by feature selection. We propose a classification algorithm where each tissue sample is considered as the center of a cluster which is a ball. The results of numerical experiments confirm that the classification algorithm in combination with the feature selection algorithm perform slightly better than the published results for multi-class classifiers based on support vector machines for this data set.

AVAILABILITY

Available on request from the authors.

Randomized controlled trial of brief cognitive behaviour therapy versus treatment as usual in recurrent deliberate self-harm: the POPMACT study

BACKGROUND

We carried out a large randomized trial of a brief form of cognitive therapy, manual-assisted cognitive behaviour therapy (MACT) versus treatment as usual (TAU) for deliberate self-harm.

METHOD

Patients presenting with recurrent deliberate self-harm in five centres were randomized to either MACT or (TAU) and followed up over 1 year. MACT patients received a booklet based on cognitive behaviour therapy (CBT) principles and were offered up to five plus two booster sessions of CBT from a therapist in the first 3 months of the study. Ratings of parasuicide risk, anxiety, depression, social functioning and global function, positive and negative thinking, and quality of life were measured at baseline and after 6 and 12 months.

RESULTS

Four hundred and eighty patients were randomized. Sixty per cent of the MACT group had both the booklet and CBT sessions. There were seven suicides, five in the TAU group. The main outcome measure, the proportion of those repeating deliberate self-harm in the 12 months of the study, showed no significant difference between those treated with MACT (39%) and treatment as usual (46%) (OR 0.78, 95% CI 0.53 to 1.14, P=0.20).

CONCLUSION

Brief cognitive behaviour therapy is of limited efficacy in reducing self-harm repetition, but the findings taken in conjunctin with the economic evaluation (Byford et al. 2003) indicate superiority of MACT over TAU in terms of cost and effectiveness combined.