Biomedical subjects

Richard Cooke

Publications and source records attributed to Richard Cooke.

At least 19 recordsLinked to original sources

PubMed2006

Predicting binge-drinking behaviour using an extended TPB: examining the impact of anticipated regret and descriptive norms.

AIMS: To investigate the utility of an extended Theory of Planned Behaviour (TPB), including descriptive norms and anticipated regret, in predicting binge-drinking intentions and behaviour. METHODS: A total of 178 undergraduates completed a questionnaire containing measures of TPB variables, descriptive norms, anticipated regret, and previous binge-drinking behaviour. One week later, 104 students completed a measure of binge-drinking behaviour. RESULTS: Hierarchical regression demonstrated that attitudes (beta = 0.30, P < 0.001) and anticipated regret (beta = 0.47, P < 0.001) were significant predictors of intentions, with the final equation accounting for 58% of the variance. Hierarchial regression found that intentions (beta = -0.21, P < 0.05) and previous binge-drinking behaviour (beta = 0.36, P < 0.01) predicted current drinking behaviour, accounting for 33% of the variance. CONCLUSIONS: The study suggests that modifying attitudes and inducing regret may be effective strategies for reducing binge-drinking intentions among undergraduates, which should reduce subsequent binge-drinking behaviour.

Adolescent↗

PubMed2006

Candidemia in patients with ventricular assist devices.

During the period 1998-2004, candidemia developed in 7 of 117 ventricular assist device recipients at our hospital, and the associated mortality rate was 71%. Five cases of candidemia were due to Candida parapsilosis, and 2 were due to Candida albicans. Three of the 7 patients with ventricular assist device-associated Candida bloodstream infections were cured, and the device was retained in 2 of the 3 patients.

Antifungal Agents↗

PubMed2006

Genome analysis of the smallest free-living eukaryote Ostreococcus tauri unveils many unique features.

The green lineage is reportedly 1,500 million years old, evolving shortly after the endosymbiosis event that gave rise to early photosynthetic eukaryotes. In this study, we unveil the complete genome sequence of an ancient member of this lineage, the unicellular green alga Ostreococcus tauri (Prasinophyceae). This cosmopolitan marine primary producer is the world's smallest free-living eukaryote known to date. Features likely reflecting optimization of environmentally relevant pathways, including resource acquisition, unusual photosynthesis apparatus, and genes potentially involved in C(4) photosynthesis, were observed, as was downsizing of many gene families. Overall, the 12.56-Mb nuclear genome has an extremely high gene density, in part because of extensive reduction of intergenic regions and other forms of compaction such as gene fusion. However, the genome is structurally complex. It exhibits previously unobserved levels of heterogeneity for a eukaryote. Two chromosomes differ structurally from the other eighteen. Both have a significantly biased G+C content, and, remarkably, they contain the majority of transposable elements. Many chromosome 2 genes also have unique codon usage and splicing, but phylogenetic analysis and composition do not support alien gene origin. In contrast, most chromosome 19 genes show no similarity to green lineage genes and a large number of them are specialized in cell surface processes. Taken together, the complete genome sequence, unusual features, and downsized gene families, make O. tauri an ideal model system for research on eukaryotic genome evolution, including chromosome specialization and green lineage ancestry.

Animals↗

PubMed2006

The neuroimaging research process from the participants' perspective.

The aim of this study was to investigate participants' experiences of taking part in research conducted using fMRI or MEG procedures. Forty-four participants completed a questionnaire after taking part in either fMRI or MEG experiments; the questionnaire asked about experiences of and attitudes toward fMRI/MEG. Ten follow-up interviews were conducted to enable an in-depth analysis of these attitudes and experiences. The findings were generally positive: all participants thought fMRI and MEG were safe procedures, 93% would recommend participating in neuroimaging research to their friends and family, and participants were positive about participating in future neuroimaging research. However, some negative issues were identified. Some participants reported feeling nervous prior to scanning procedures, several participants reported side-effects after taking part, a number of participants were upset at being in a confined space and some participants did not feel confident about exiting the scanner in an emergency. Several recommendations for researchers are made, including a virtual tour of the scanning equipment during the consenting process in order to better prepare potential participants for the scanning experience and to minimize the potential psychological discomfort sometimes experienced in neuroimaging research.

Adolescent↗

PubMed2006

High protein pre-term infant formula: effect on nutrient balance, metabolic status and growth.

Several lines of evidence suggest that formula with protein content of 3.0 g/100 kcal does not fully meet the protein needs of very-low-birth weight infants. Our purpose was to compare nitrogen balance, metabolic status and growth in infants fed a standard (3.0 g/100 kcal; RegPro) and high (3.6 g/100 kcal; HiPro) protein infant formula. Infants were fed both formulas, each formula for one week in balanced cross-over design. Metabolic status was monitored throughout. Nutrient balance and plasma amino acids were determined at the end of each week. Data were analysed using a linear mixed model. Eighteen infants were studied. Nine infants received the RegPro and nine received HiPro formula first. Nitrogen intake, absorption and retention were greater with the HiPro formula. None of the infants developed uremia or metabolic acidosis but retinol-binding-protein and weight gain were greater with the HiPro formula. Increased protein accretion paralleled by better weight gain without evidence of metabolic stress indicates that a formula with a protein content of 3.6 g/100 kcal better meets protein needs in these rapidly-growing infants. Further studies are needed to determine whether these short-term outcomes will be translated into long-term benefits.

Cross-Over Studies↗

PubMed2005

One year outcomes for heroin dependence: findings from the Australian Treatment Outcome Study (ATOS).

AIM: To determine 1 year outcomes for drug use, criminality, psychopathology and injection-related health problems in those entering treatment for heroin dependence in Australia. DESIGN: Longitudinal prospective cohort study. PARTICIPANTS: Seven hundred and forty five individuals entering treatment (methadone/buprenorphine maintenance therapy; detoxification; residential rehabilitation) and 80 heroin users not seeking treatment. SETTING: Sydney, Melbourne and Adelaide, Australia. FINDINGS: A total of 657 individuals were re-interviewed at 1 year, 80% of the original sample. There were substantial reductions in heroin and other drug use across all three treatment modalities. The majority of those who had entered treatment were heroin abstinent at 1 year (maintenance therapy 65%, detoxification 52%, residential rehabilitation 63%) compared to 25% of the non-treatment sample. The reduction in heroin use among the treatment samples was paralleled by reductions in poly drug use. There were also substantial reductions in risk-taking, crime and injection-related health problems across all treatment groups, and less marked reductions among the non-treatment group. Psychopathology was dramatically reduced among the treatment modalities, while remaining stable among the non-treatment group. Positive outcomes at 1 year were associated with a greater number of cumulative treatment days experienced over the 1 year follow-up period ('treatment dose') and fewer treatment episodes undertaken in that time ('treatment stability'). CONCLUSIONS: At 1 year, there were impressive reductions in drug use, criminality, psychopathology and injection-related health problems following treatment exposure. The positive findings were associated with a greater "dose" of treatment, and with more treatment stability over the follow-up period.

Adolescent↗

PubMed2005

GeneFarm, structural and functional annotation of Arabidopsis gene and protein families by a network of experts.

Genomic projects heavily depend on genome annotations and are limited by the current deficiencies in the published predictions of gene structure and function. It follows that, improved annotation will allow better data mining of genomes, and more secure planning and design of experiments. The purpose of the GeneFarm project is to obtain homogeneous, reliable, documented and traceable annotations for Arabidopsis nuclear genes and gene products, and to enter them into an added-value database. This re-annotation project is being performed exhaustively on every member of each gene family. Performing a family-wide annotation makes the task easier and more efficient than a gene-by-gene approach since many features obtained for one gene can be extrapolated to some or all the other genes of a family. A complete annotation procedure based on the most efficient prediction tools available is being used by 16 partner laboratories, each contributing annotated families from its field of expertise. A database, named GeneFarm, and an associated user-friendly interface to query the annotations have been developed. More than 3000 genes distributed over 300 families have been annotated and are available at http://genoplante-info.infobiogen.fr/Genefarm/. Furthermore, collaboration with the Swiss Institute of Bioinformatics is underway to integrate the GeneFarm data into the protein knowledgebase Swiss-Prot.

Arabidopsis↗

PubMed2005

Gene expression profile in response to Xanthomonas axonopodis pv. manihotis infection in cassava using a cDNA microarray.

A cassava cDNA microarray based on a large cassava EST database was constructed and used to study the incompatible interaction between cassava and Xanthomonas axonopodis pv. manihotis (Xam) strain CIO151. For microarray construction, 5700 clones from the cassava unigene set were amplified by polymerase chain reaction (PCR) and printed on glass slides. Microarray hybridization was performed using cDNA from cassava plants (resistant variety MBra685) collected at 12, 24, 48 h and 7 and 15 days post-infection as treatment and cDNA from mock-inoculated plants as control. A total of 199 genes were found to be differentially expressed (126 up-regulated and 73 down-regulated). A greater proportion of differentially-expressed genes was observed at 7 days after inoculation. Expression profiling and cluster analyses indicate that, in response to inoculation with Xam, cassava induces dozens of genes, including principally those involved in oxidative burst, protein degradation and pathogenesis-related (PR) genes. In contrast, genes encoding proteins that are involved in photosynthesis and metabolism were down regulated. In addition, various other genes encoding proteins with unknown function or showing no similarity to other proteins were also induced. Quantitative real time PCR experiments confirmed the reliability of our microarray data. In addition we showed that some genes are induced more rapidly in the resistant than in the susceptible cultivar.

Cluster Analysis↗

PubMed2005

Factors associated with 12 months continuous heroin abstinence: findings from the Australian Treatment Outcome Study (ATOS).

AIMS: To determine the role of treatment and client characteristics associated with the achievement of continuous heroin abstinence. DESIGN: Longitudinal cohort study. SETTING: Sydney and Adelaide, Australia. PARTICIPANTS: 570 heroin users re-interviewed at 12 month follow-up for the Australian Treatment Outcome Study (ATOS). FINDINGS: Continuous heroin abstinence was reported by 14% of participants. Continuous abstinence was associated with no previous treatment history, having entered treatment at baseline, and cumulative treatment exposure over the follow-up period. Longer retention times in index maintenance and residential rehabilitation treatments, but not detoxifications, were most associated with abstinence. At baseline, abstinent participants were more likely to have been classified as treatment ready, or to have used heroin less frequently; and less likely to have been daily injectors, using cocaine or criminally involved. CONCLUSIONS: Approximately 14% of ATOS participants achieved continuous heroin abstinence over 12 months. Such an achievement was strongly associated with a longer "dose" of treatment, and with more treatment stability over the follow-up period.

Adolescent↗

PubMed2005

Postnatal growth in preterm infants: have we got it right?

Postnatal growth retardation appears inevitable in preterm infants. This partly reflects an inability to establish adequate dietary intakes in a timely fashion in the sick, unstable immature infant. However, it may also reflect inherent errors in current recommendation as well as systematic errors in the way nutrient requirements are estimated in these high-risk infants. These issues are addressed in this article.

Energy Intake↗

PubMed2005

The characteristics of heroin users entering treatment: findings from the Australian treatment outcome study (ATOS).

The current study aimed to describe the characteristics (demographics, drug use, mental and physical health) of entrants to treatment for heroin dependence in three treatment modalities; and to compare these characteristics with heroin users not in or seeking treatment. Participants were 825 current heroin users recruited from Sydney, Adelaide and Melbourne: 277 entering methadone/buprenorphine maintenance treatment (MT), 288 entering detoxification (DTX), 180 entering drug-free residential rehabilitation (RR) and 80 not in treatment (NT). Treatment entrants were generally long-term heroin users with previous treatment experience. The majority of the sample (55%) were criminally active in the month preceding interview. Injection-related health problems (74%) and a history of heroin overdose (58%) were commonly reported. There were high degrees of psychiatric co-morbidity, with 49% reporting severe psychological distress, 28% having current major depression, 37% having attempted suicide and 42% having a lifetime history of post-traumatic stress disorder. Personality disorders were also prevalent, with 72% meeting criteria for antisocial personality disorder and 47% screening positive for borderline personality disorder. Striking similarities were noted between the non-treatment and treatment groups in length of heroin use career, drug use and treatment histories.

Adult↗

PubMed2005

The goal-dependent automaticity of drinking habits.

In recent treatments of habitual social behaviour, habits are conceptualized as a form of goal-directed automatic behaviour that are mentally represented as goal-action links. Three experiments tested this conceptualization in the context of students' drinking (alcohol consumption)habits. Participants were randomly assigned to conditions where either a goal related to drinking behaviour (socializing) was activated, or an unrelated goal was activated. In addition, participants' drinking habits were measured. The dependent variable in Experiments 1 and 2 was readiness to drink, operationalized by speed of responding to the action concept 'drinking' in a verb verification task. Experiment 3 used the uptake of a voucher to measure drinking behaviour. Findings supported the view that when habits are established, simply activating a goal related to the focal behaviour automatically elicits that behaviour. These findings are consistent with a goal-dependent conception of habit. Possibilities for interventions designed to attenuate undesirable habitual behaviours are considered.

Adolescent↗

PubMed2004

A unigene catalogue of 5700 expressed genes in cassava.

Two economically important characters, starch content and cassava bacterial blight resistance, were targeted to generate a large collection of cassava ESTs. Two libraries were constructed from cassava root tissues of varieties with high and low starch contents. Other libraries were constructed from plant tissues challenged by the pathogen Xanthomonas axonopodis pv.manihotis. We report here the single pass sequencing of 11,954 cDNA clones from the 5' ends, including 111 from the 3' ends. Cluster analysis permitted the identification of a unigene set of 5,700 sequences. Sequence analyses permitted the assignment of a putative functional category for 37% of sequences whereas approximately 16% sequences did not show any significant similarity with other proteins present in the database and therefore can be considered as cassava specific genes. A group of genes belonging to a large multigene family was identified. We characterize a set of genes detected only in infected libraries putatively involved in the defense response to pathogen infection. By comparing two libraries obtained from cultivars contrasting in their starch content a group of genes associated to starch biosynthesis and differentially expressed was identified. This is the first large cassava EST resource developed today and publicly available thus making a significant contribution to genomic knowledge of cassava.

Cluster Analysis↗

PubMed2004

An EST resource for cassava and other species of Euphorbiaceae.

Cassava (Manihot esculenta) is a major food staple for nearly 600 million people in Africa, Asia, and Latin America. Major losses in yield result from biotic and abiotic stresses that include diseases such as Cassava Mosaic Disease (CMD) and Cassava Bacterial Blight (CBB), drought, and acid soils. Additional losses also occur from deterioration during the post-harvest storage of roots. To help cassava breeders overcome these obstacles, the scientific community has turned to modern genomics approaches to identify key genetic characteristics associated with resistance to these yield-limiting factors. One approach for developing a genomics program requires the development of ESTs (expressed sequence tags). To date, nearly 23,000 ESTs have been developed from various cassava tissues, and genotypes. Preliminary analysis indicates existing EST resources contain at least 6000-7000 unigenes. Data presented in this report indicate that the cassava ESTs will be a valuable resource for the study of genetic diversity, stress resistance, and growth and development, not only in cassava, but also other members of the Euphorbiaceae family.

Alleles↗

PubMed2004

Heroin users in Australia: population trends.

The aim of this paper is to identify certain important population trends among heroin users in Australia for the period 1971 - 97, such as: population growth, initiation, i.e. the number who were initiated to heroin in a given year, and quitting, i.e. the number that quit using heroin. For this purpose, we summarize and extract relevant characteristics from data from National Drug Strategy Household Survey (NDSHS 1998) conducted in Australia in 1998. We devise a systematic procedure to estimate historical trends from questions concerning past events. It is observed from our findings that the size of the heroin user population in Australia is in a sharp increase, especially from the early 1980s onwards. The general trend obtained for the period 1971 - 97 is strikingly similar to that obtained by Hall et al. (2000) for the dependent heroin user population in Australia, even though their study was based on different datasets and a different methodology. In our reconstruction of the time history we also detect a levelling-off prior to 1990. Initiation is also observed to be on a sharp increase. The latter trend is accompanied by a similar trend of quitting, perhaps indicating a relatively short heroin use career. A sharp decrease in both initiation and quitting is observed after 1990. In conclusion, in the case of the trend in the population of heroin users a high rate of growth has been identified that is consistent with the existing literature. In the process, we demonstrated that even a static survey such as NDSHS 1998 can, sometimes, be used to extract historical (dynamic) trends of certain important variables.

Adolescent↗

PubMed2004

The Arabidopsis root transcriptome by serial analysis of gene expression. Gene identification using the genome sequence.

Large-scale identification of genes expressed in roots of the model plant Arabidopsis was performed by serial analysis of gene expression (SAGE), on a total of 144,083 sequenced tags, representing at least 15,964 different mRNAs. For tag to gene assignment, we developed a computational approach based on 26,620 genes annotated from the complete sequence of the genome. The procedure selected warrants the identification of the genes corresponding to the majority of the tags found experimentally, with a high level of reliability, and provides a reference database for SAGE studies in Arabidopsis. This new resource allowed us to characterize the expression of more than 3,000 genes, for which there is no expressed sequence tag (EST) or cDNA in the databases. Moreover, 85% of the tags were specific for one gene. To illustrate this advantage of SAGE for functional genomics, we show that our data allow an unambiguous analysis of most of the individual genes belonging to 12 different ion transporter multigene families. These results indicate that, compared with EST-based tag to gene assignment, the use of the annotated genome sequence greatly improves gene identification in SAGE studies. However, more than 6,000 different tags remained with no gene match, suggesting that a significant proportion of transcripts present in the roots originate from yet unknown or wrongly annotated genes. The root transcriptome characterized in this study markedly differs from those obtained in other organs, and provides a unique resource for investigating the functional specificities of the root system. As an example of the use of SAGE for transcript profiling in Arabidopsis, we report here the identification of 270 genes differentially expressed between roots of plants grown either with NO3- or NH4NO3 as N source.

Arabidopsis↗

PubMed2004

New in silico insight into the synteny between rice (Oryza sativa L.) and maize (Zea mays L.) highlights reshuffling and identifies new duplications in the rice genome.

A unigene set of 1411 contigs was constructed from 2629 redundant maize expressed sequence tags (ESTs) mapped on the maizeDB genetic map. Rice orthologous sequences were identified by blast alignment against the rice genomic sequence. A total of 1046 (74%) maize contigs were associated with their corresponding homologues in the rice genome and 656 (47%) defined as potential orthologous relationships. One hundred and seventeen (8%) maize EST contigs mapped to two distinct loci on the maize genetic map, reflecting the tetraploid nature of the maize genome. Among 492 mono-locus contigs, 344 (484 redundant ESTs) identify collinear blocks between maize chromosomes 2 and 4 and a single rice chromosome, defining six new collinear regions. Fine-scale analysis of collinearity between rice chromosomes 1 and 5 with maize chromosomes 3, 6 and 8 shows the presence of internal rearrangements within collinear regions. Mapping of maize contigs to two distinct loci on the rice sequence identifies five new duplication events in rice. Detailed analysis of a duplication between rice chromosomes 1 and 5 shows that 11% of the annotated genes from the chromosome 1 locus are found duplicated on the chromosome 5 paralogous counterpart, indicating a high degree of re-organisations. The implications of these findings for map-based cloning in collinear regions are discussed.

Chromosome Mapping↗

PubMed2004

Moderation of cognition-intention and cognition-behaviour relations: a meta-analysis of properties of variables from the theory of planned behaviour.

Meta-analysis was used to quantify the moderating effects of seven properties of cognitions-accessibility, temporal stability, direct experience, involvement, certainty, ambivalence and affective-cognitive consistency-on cognition-intention and cognition-behaviour relations. Literature searches revealed 44 studies that could be included in the review. Findings showed that all of the properties, except involvement, moderated attitude-behaviour consistency. Similarly, all relevant moderators improved the consistency between intentions and behaviour. Temporal stability moderated PBC-behaviour relations, certainty moderated subjective norm-intention relations, and ambivalence, certainty, and involvement all moderated attitude-intention relations. Overall, temporal stability appeared to be the strongest moderator of cognition-behaviour relations.

Affect↗