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J Austin

Publications and source records attributed to J Austin.

At least 37 records · Page 2Linked to original sources
PubMed2000

Comparative sequencing and association studies of aromatic L-amino acid decarboxylase in schizophrenia and bipolar disorder.

Aromatic L-amino acid decarboxylase (AADC) is a relatively non specific enzyme involved in the biosynthesis of several classical neurotransmitters including dopamine and 5-hydroxytryptamine (5HT; serotonin). AADC does not catalyse the rate limiting step in either pathway, but is rate limiting in the synthesis of 2-phenylethylamine (2PE) which is a positive modulator of dopaminergic transmission and a candidate natural psychotogenic compound.1 We and others have proposed that polymorphism in AADC resulting in altered 2PE activity might contribute to the pathogenesis of psychosis. In order to test this hypothesis, we have used denaturing high performance liquid chromatography (DHPLC)3 to screen 3943 bases of the AADC gene and its promoter regions for variants that might affect protein structure or expression in 15 unrelated people with schizophrenia, and 15 unrelated people with bipolar disorder. Three polymorphisms were identified by DHPLC: a insertion/deletion polymorphism in the 5' UTR of the neuronal specific mRNA (g.-33-30delAGAG, bases 586-589 of GenBank M77828), a T>A variant in the non-neuronal exon 1 (g. -67T>A, GenBank M88070), and a G>A polymorphism within intron 8 (g. IVS8 +75G>A, GenBank M84598). Case-control analysis did not suggest that genetic polymorphism in the AADC gene is associated with liability for developing schizophrenia or bipolar disorder.

Aromatic-L-Amino-Acid Decarboxylases↗
PubMed2000

The high affinity neurotensin receptor gene (NTSR1): comparative sequencing and association studies in schizophrenia.

Neurotensin and its high affinity receptor (NTSR1) localise within dopaminergic neurones in the mesocortical, mesolimbic and nigrostriatal systems and it is now clear that neurotensin can selectively modulate dopaminergic neurotransmission. This has led to the hypothesis that altered neurotensin function contributes to the pathogenesis of schizophrenia and other psychoses. This hypothesis has been supported circumstantially by a number of lines of evidence. (1) Central administration of neurotensin produces effects similar to those produced by the peripheral administration of atypical antipsychotics. (2) Observations of low levels of neurotensin in the CSF of schizophrenics. (3) Reduced numbers of neurotensin receptors in the brains of schizophrenics. Given the above link between neurotensin and dopamine, and the evidence implicating altered neurotensin function in psychosis, we have postulated that DNA sequence variation in neurotensin or its receptors might be associated with schizophrenia. In keeping with this hypothesis, an association has recently been reported between schizophrenia and the gene encoding the neurotensin high affinity receptor (NTSR1). However, caution is required because the associated marker, a tetranucleotide repeat, is located 3 kb away from the 3' end of the gene and there is no evidence that it is functional. Therefore, as a follow-up to our earlier work on neurotensin, we have now sought to test the hypothesis that DNA sequence variants that alter the structure or expression of the NTSR1 gene (VAPSEs) are associated with schizophrenia. However, while we found 14 novel sequence variants in 28 probands with psychosis, none resulted in an amino acid change, and neither direct nor indirect association studies suggested these are involved in susceptibility to schizophrenia.

Brain Chemistry↗
PubMed2000

HIV, hepatitis C and risk behaviour in a Canadian medium-security federal penitentiary. Queen's University HIV Prison Study Group.

In a voluntary anonymous HIV and hepatitis C serology screen in a Canadian male medium security federal penitentiary, 68% of 520 prisoners volunteered a blood sample and 99% of those giving a blood sample completed a risk behaviour questionnaire which was linked numerically to the blood sample. Compared to previous screenings for HIV (4 years earlier), and hepatitis C (3 years earlier) in the same institution, HIV seroprevalence had risen from 1% to 2% and hepatitis C seroprevalence from 28% to 33%. The overwhelming risk association for hepatitis C was with drug use outside prison, although there was a small group of men who had only ever injected drugs inside prison, over half of whom had been infected with hepatitis C. The proportion of prisoners who had injected drugs in prison rose from 12% in 1995 to 24% in 1998. The proportion of surveyed individuals sharing injection equipment at some time in prison was 19%, and while HIV rates in the prison are currently low, HIV prevalence amongst Canadian street i.v. drug users is rising rapidly, underlining the need for urgent preventative measures in prisons.

HIV Seropositivity↗
PubMed2000

Association analysis of the proneurotensin gene and bipolar disorder.

Neurotensin (NT) localizes within dopaminergic neurones in the mesocortical, mesolimbic and nigrostriatal systems, and it is now clear that NT can selectively modulate dopaminergic neurotransmission. It has therefore been proposed that altered NT function might contribute to the pathogenesis of neuropsychiatric disorders in which disordered dopaminergic neurotransmission is suspected. We have previously screened the gene encoding NT in a sample of schizophrenic and bipolar subjects, and identified three sequence variants. These have now been tested for association with bipolar disorder using a case-control sample of unrelated bipolar subjects and matched controls. No evidence for association was found, and our data therefore suggest that sequence variation in this gene does not make an important contribution to susceptibility to bipolar disorder.

Adult↗
PubMed2000

Early management of patients with back pain.

Early effective management of acute back pain reduces the likelihood of chronicity and disability occurring. Multidisciplinary team working greatly enhances the potential for early resolution of symptoms and return to normal activities. Good quality referral from primary care using CSAG guidelines helps clinicians in secondary care to accurately categorise and prioritise care.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1999

Genotyping single nucleotide polymorphisms by primer extension and high performance liquid chromatography.

We have investigated the possibility of genotyping single nucleotide polymorphisms (SNPs) by primer extension and high performance liquid chromatography (HPLC). Using three polymorphisms of current interest to our group (an A/G polymorphism in the proneurotensin gene and A/G and T/C polymorphisms in the 5HT2a receptor gene), we show that robust signal is obtained using this simple analytic method which has the added advantages that sample loading and analysis are essentially automated, analytic time is brief, and no further purification step after primer extension is required. We also show that all stages of the HPLC-primer extension genotyping can be multiplexed which, together with automation, suggests that this system may be suitable for linkage studies based upon emerging SNP maps.

Base Sequence↗
PubMed1999

Standards for batterer intervention programs in Canada: a history and review.

This article reports on the growing trend of setting standards for intervention with batterers. All existing Canadian standards for batterer intervention programs (BIPs) are examined, including a discussion on how they came into effect and any controversy associated with their development. A brief background of the battering intervention field and the growth of BIP standards in North America is provided, followed by a description of the types and content of Canadian standards. Compliance with standards were mandatory in two regions and voluntary in three others. Two more regions had standards in a draft stage of development. Elements of standards typically included directives on: general program goals; the protocol and procedures programs should follow, including counselling format; and program staff ethics and qualifications. The article concludes with a discussion of the findings and suggestions for improving standards.

Canada↗
PubMed1999

Optimal temperature selection for mutation detection by denaturing HPLC and comparison to single-stranded conformation polymorphism and heteroduplex analysis.

BACKGROUND: Denaturing HPLC (DHPLC) is a semi-automated method for detecting unknown DNA sequence variants. The sensitivity of the method is dependent on the temperature at which the analysis is undertaken, the selection of which is dependent on operator experience. To circumvent this, software has been developed for predicting the optimal temperature for DHPLC analysis. We examined the utility of this software. METHODS: To maximize the relevance of our data for other investigators, we have screened 42 different amplimers from CFTR, TSC1, and TSC2. The samples consisted of 103 unique sequence heterozygotes and 126 wild-type homozygous controls. RESULTS: At the temperature recommended by the software, 96% (99 of 103) of heterozygotes and all of the wild-type controls were correctly classified. This compares favorably with sensitivities of 85% for single-stranded conformation polymorphism and 82% for gel-based heteroduplex analyses of the same fragments. CONCLUSIONS: Software-optimized DHPLC is a highly sensitive method for mutation detection. However, where sensitivity >96% is required, our data suggest that in addition to the recommended temperature, fragments should also be run at the recommended temperature plus 2 degrees C.

Chromatography, High Pressure Liquid↗
PubMed1998

Blind analysis of denaturing high-performance liquid chromatography as a tool for mutation detection.

Denaturing high-performance liquid chromatography (DHPLC) is a novel high-capacity technique for detecting new mutations. We have evaluated the sensitivity and specificity of this method in a blind analysis of exon H of the factor IX gene and exon 16 of the neurofibromatosis type 1 gene. Under a single set of conditions for each exon, 55/55 individuals carrying 48 unique mutations were correctly identified as were 55/55 individuals with wildtype alleles. We conclude that DHPLC is a highly sensitive and specific method for mutation detection.

Chromatography, High Pressure Liquid↗
PubMed1998

Prevalence of asthma symptoms, diagnosis, and treatment in 12-14 year old children across Great Britain (international study of asthma and allergies in childhood, ISAAC UK)

OBJECTIVE: To investigate variations in the prevalence of self reported symptoms, diagnosis, and treatment of asthma in 12-14 year old children. DESIGN: Self completion questionnaire. SETTING: Great Britain. SUBJECTS: All pupils aged 12-14 years in a stratified cluster sample of 93 large mixed secondary schools in 1995. MAIN OUTCOME MEASURES: Self reported prevalence of symptoms, diagnosis, and treatment of asthma at four geographical levels. RESULTS: 27,507 questionnaires were completed (85.9% response rate). The national 12 month prevalence of any wheezing, speech limiting wheeze, four or more attacks of wheeze, and frequent night waking with wheeze was 33.3% (n = 9155), 8.8% (2427), 9.6% (2634), and 3.7% (1023) respectively. The prevalence of ever having had a diagnosis of asthma was 20.9% (5736). In total, 19.8% (5438/27,507) of pupils reported treatment with anti-asthma drugs in the past year, but, of pupils reporting frequent nocturnal wheeze in the past year, 33.8% (342/1012) had no diagnosis of asthma and 38.6% (395/1023) denied receiving inhaler therapy. The 12 month prevalence of wheeze was highest in Scotland (36.7%, 1633/4444), but in England and Wales there was no discernible north-south or east-west gradient. Wheeze prevalence was slightly higher in non-metropolitan areas (35.0%, 6155/17,605) than in metropolitan areas (30.3%, 3000/9902). The prevalence of self reported asthma diagnosis and inhaler use showed no discernible national, regional, north-south, or east-west geographical pattern but was higher in non-metropolitan areas. CONCLUSION: Prevalence of self reported symptoms, diagnosis, and treatment of asthma was high among 12-14 year olds throughout Great Britain with little geographical or urban-rural variation. Underdiagnosis and undertreatment were substantial.

Adolescent↗
PubMed1998

Development of scales to measure psychosocial care needs of children with seizures and their parents. 1.

There is little research and no self-report assessment instruments available to guide nurses in the provision of psychosocial care to children with seizures and their families. Information on the development of two instruments, Report of Psychosocial Care Scale and Child Report of Psycyhosocial Care Scale, and their use in a research study to measure psychosocial care of children with new-onset seizures and their parents are presented in three parts. This first article describes development and initial testing of their psychometric properties. The second article, Part 2, "Psychosocial Care Needs of Parents of Children with New-Onset Seizures," describes results from the use of the parent scale with mothers and fathers of children with new-onset seizures. The third article, Part 3, "Psychosocial Care Needs of Children with New-Onset Seizures," reports findings from the use of the child scale with children ages 8-14 years with new-onset seizures.

Adaptation, Psychological↗
PubMed1998

Psychosocial care needs of children with new-onset seizures. 2.

The Child Report of Psychosocial Care Scale was used to measure children's satisfaction with health care received, need for information and support and seizure-related concerns and fears in children with new-onset seizures. The sample of 63 children (33 girls and 30 boys), 8-14 years, completed the scale two times, 3 months and 6 months after their first seizure. Results indicated that children need the most nursing care in two areas: information related to the seizure condition, especially managing their condition, and support, in the form of talking to other children with seizures. The scale provides direction for tailored nursing interventions that will meet the specific needs of children with seizures for information and support.

Adaptation, Psychological↗
PubMed1998

Psychosocial care needs of parents of children with new-onset seizures. 3.

The Parent Report of Psychosocial Care was developed to address the concerns, needs for care and satisfaction with care received of parents of children with new-onset seizures. Parents were interviewed three months and six months after their child's first seizures using the instrument. Mothers especially identified continued needs for information and support and were worried about unlikely events such as brain tumors and death. The results from this study indicate that parents' needs for information and support need to be assessed at every encounter with the health care system during the first 6 months after the child's first seizure.

Adaptation, Psychological↗
PubMed1998

sma-1 encodes a betaH-spectrin homolog required for Caenorhabditis elegans morphogenesis.

Morphogenesis transforms the C. elegans embryo from a ball of cells into a vermiform larva. During this transformation, the embryo increases fourfold in length; present data indicates this elongation results from contraction of the epidermal actin cytoskeleton. In sma-1 mutants, the extent of embryonic elongation is decreased and the resulting sma-1 larvae, although viable, are shorter than normal. We find that sma-1 mutants elongate for the same length of time as wild-type embryos, but at a decreased rate. The sma-1 mutants we have isolated vary in phenotypic severity, with the most severe alleles showing the greatest decrease in elongation rate. The sma-1 gene encodes a homolog of betaH-spectrin, a novel beta-spectrin isoform first identified in Drosophila. sma-1 RNA is expressed in epithelial tissues in the C. elegans embryo: in the embryonic epidermis at the start of morphogenesis and subsequently in the developing pharynx, intestine and excretory cell. In Drosophila, betaH-spectrin associates with the apical plasma membrane of epithelial cells; beta-spectrin is found at the lateral membrane. We propose that SMA-1 is a component of an apical membrane skeleton in the C. elegans embryonic epidermis that determines the rate of elongation during morphogenesis.

Amino Acid Sequence↗
PubMed1997

Detection of RAPD markers correlated with chloroquine resistance in Plasmodium falciparum.

We described the use of the random amplified polymorphic DNA (RAPD) technique on Plasmodium falciparum DNA to detect genetic markers for chloroquine-resistant strains. Fourteen RAPD primers were tested, three of which generated banding patterns correlated with chloroquine resistance. To measure this correlation, the RAPD profiles were analyzed using the Nei and Li similarity coefficient. Detection of distinctive RAPD bands allowed us to synthesize specific PCR primers to be used on whole-blood samples. Two primer sets were synthesized and tested on sensitive and resistant strains for their ability to amplify the DNA fragment corresponding to the RAPD marker. These results suggest that RAPD and PCR techniques can be used as powerful tools for the detection of genetic markers associated with drug resistance.

Animals↗