Apparent insensitivity of the hotplate latency test for detection of antinociception following intraperitoneal, intravenous or intracerebroventricular M6G administration to rats

Although morphine-6-glucuronide (M6G) has been shown to be analgesically active, the relative involvement of spinal and supraspinal structures in mediating M6G's pain-relieving effects following central and systemic administration to rats is unclear. As the tail flick and hotplate latency tests are reported to quantify antinociception mediated primarily by spinal and supraspinal mechanisms respectively, these methods were used to determine the comparative apparent levels of antinociception (expressed as percentage maximum possible effect, % MPE) achieved after M6G or morphine administration. Following i.v. or i.p. M6G (1.9-5.4 mu mol) dosing or i.p. morphine (10 mu mol) dosing, high levels of antinociception (>50% MPE) were achieved using the tail flick test whereas base-line levels of antinociception were observed 30 sec later in the same rats using the hotplate test. By contrast, antinociception evoked by i.v. morphine (10 mu mol) exceeded 50% MPE using both the hotplate and tail flick tests although the apparent potency was approximately 2.5 times greater using the tail flick test. After i.c.v. dosing, M6G (0.22-3.3 nmol) was significantly (P < .05) more potent when assessed using the tail flick compared with the hotplate test. Taken together, these data strongly indicate that following central and systemic administration, M6G's antinociceptive effects are mediated primarily by spinal structures whereas both spinal and supraspinal mechanisms contribute to systemic morphine's antinociceptive effects.

Educational characteristics of students with high or low self-concept

In response to methodological concerns associated with previous research into the educational characteristics of students with high or low self-concept, the topic was re-examined using a significantly more representative sample and a contemporary self-concept measure. From an initial screening of 515 preadolescent, coeducational students in 18 schools, students significantly high or low in self-concept were compared using standardized tests in reading, spelling, and mathematics, and teacher interviews to determine students' academic and nonacademic characteristics. The teachers were not informed of the self-concept status of the students. Compared to students with low self-concept, students with high self-concept were rated by teachers as being more popular, cooperative, and persistent in class, showed greater leadership, were lower in anxiety, had more supportive families, and had higher teacher expectations for their future success. Teachers observed that students with low self-concept were quiet and withdrawn, while peers with high self-concept were talkative and more dominating with peers. Students with lower self-concepts were also lower than their peers in reading, spelling, and mathematical abilities. The findings support the notion that there is an interactive relationship between self-concept and achievement. (C) 1998 John Wiley & Sons, Inc.

Administration of growth hormone or IGF-I to pregnant rats on a reduced diet throughout pregnancy does not prevent fetal intrauterine growth retardation and elevated blood pressure in adult offspring

Increasing evidence from human epidemiological studies suggests that poor growth before birth is associated with postnatal growth retardation and the development of cardiovascular disease in adulthood. We have shown previously that nutritional deprivation in the pregnant rat leads to intrauterine growth retardation (IUGR), postnatal growth failure, changes in the endocrine parameters of the somatotrophic axis, and to increased blood pressure in later life. In the present study, we investigated whether administration of insulin-like growth factor-I (IGF-I) or bovine growth hormone (GH) during pregnancy could prevent IUGR and/or alter long-term outcome. Dams h-om day 1 of pregnancy throughout gestation received a diet of nd libitum available food or a restricted dietary intake of 30% of ad libitum fed dams. From day 10 of gestation, dams were treated for 10 days with three times daily subcutaneous injections of saline (100 mu l), IGF-I (2 mu g/g body weight) or GH (2 mu g/g body weight). Maternal weight gain was significantly increased (P

The effects of adolescent cannabis use on educational attainment: a review

This paper reviews research examining the link between cannabis use and educational attainment among youth. Cross-sectional studies have revealed significant associations between cannabis use and a range of measures of educational performance including lower grade point average, less satisfaction with school, negative attitudes to school, increased rates of school absenteeism and poor school performance. However, results of cross-sectional studies cannot be used to determine whether cannabis use causes poor educational performance, poor educational performance is a cause of cannabis use or whether both outcomes are a reflection of common risk factors. Nonetheless, a number of prospective longitudinal studies have indicated that early cannabis use may significantly increase risks of subsequent poor school performance and, in particular, early school leaving. This association has remained after control for a wide range of prospectively assessed covariates. Possible mechanisms underlying an association between early cannabis use and educational attainment include the possibility that cannabis use induces an 'amotivational syndrome' or that cannabis use causes cognitive impairment. However, there appears to be relatively little empirical support for these hypotheses. It is proposed that the link between early cannabis use and educational attainment arises because of the social context within which cannabis is used. In particular, early cannabis use appears to be associated with the adoption of an anti-conventional lifestyle characterized by affiliations with delinquent and substance using peers, and the precocious adoption of adult roles including early school leaving, leaving the parental home and early parenthood.

Systemic administration of antisense p75(NTR) oligodeoxynucleotides rescues axotomised spinal motor neurons

The 75 kD low-affinity neurotrophin receptor (p75(NTR)) is expressed in developing and axotomised spinal motor neurons. There is now convincing evidence that p75NTR can, under some circumstances, become cytotoxic and promote neuronal cell death. We report here that a single application of antisense p75(NTR) oligodeoxynucleotides to the proximal nerve stumps of neonatal rats significantly reduces the loss of axotomised motor neurons compared to controls treated with nonsense oligodeoxynucleotides or phosphate-buffered saline. Our investigations also show that daily systemic intraperitoneal injections of antisense p75(NTR) oligodeoxynucleotides for 14 days significantly reduce the loss of axotomised motor neurons compared to controls. Furthermore, we found that systemic delivery over a similar period continues to be effective following axotomy when intraperitoneal injections were 1) administered after a delay of 24 hr, 2) limited to the first 7 days, or 3) administered every third day. In addition, p75(NTR) protein levels were reduced in spinal motor neurons following treatment with antisense p75(NTR) oligodeoxynucleotides. There were also no obvious side effects associated with antisense p75(NTR) oligodeoxynucleotide treatments as determined by behavioural observations and postnatal weight gain. Our findings indicate that antisense-based strategies could be a novel approach for the prevention of motor neuron degeneration associated with injuries or disease. (C) 2001 Wiley-Liss, Inc.

An overview of diversion strategies for Australian drug-related offenders

This paper provides a descriptive overview of options for diversion of drug-related offenders from the criminal justice system. Drug-related offences include drug offences (for example, possession of a prohibited substance); offences that are directly linked to intoxication (for example, drink-driving or assault); and offences committed to support drug use (for example, theft). After an offence has been detected by police, multiple opportunities for diversion occur throughout the criminal justice process. (a) Pre-arrest: when an offence is first detected, prior to a charge being laid. This is known as police diversion and includes fines, warnings and cautions, sometimes with educational information or referral to assessment and treatment. (b) Pre-trial: when a charge is made but before the matter is heard at court. Examples are treatment as a condition of bail, conferencing and prosecutor discretion. (c) Pre-sentence: a delay of sentence while assessment and treatment are sought. (d) Post-sentence: as part of sentencing, for example suspended sentences, drug courts, noncustodial sentences and circle sentencing. (e) Pre-release: prior to release from a sentence, on parole. Issues for diversion programmes include net widening, the ethics of coercion to treatment, the needs of families and intersectoral collaboration. A framework for diversion is presented in which increasingly treatment-focused and coercive diversion strategies are used as offenders' criminal careers and drug problems increase.

Organisational Factors Contributing to Violations by Rural and Remote Area Nurses during Medication Administration

Medication errors are a leading cause of unintended harm to patients in Australia and internationally. Research in this area has paid relatively little attention to the interactions between organisational factors and violations of procedures in producing errors, although violations have been found to increase the likelihood of these errors. This study investigated the role of organisational factors in contributing to violations by nurses when administering medications. Data were collected using a self-report questionnaire completed by 506 nurses working in either rural or remote areas in Queensland, Australia. This instrument was used to develop a path model wherein organisational variables predicted 21% of the variance in self-reported violations. Expectations of medical officers mediated the relationship between working conditions of nursing staff and violation behaviour.

Mediatizing educational policy: The journalistic field, science policy, and cross-field effects

This paper is concerned to demonstrate the usefulness of the theory of Bourdieu, including the concepts of field, logics of practice and habitus, to understanding relationships between media and policy, what Fairclough has called the 'mediatization' of policy. Specifically, the paper draws upon Bourdieu's accessible account of the journalistic field as outlined in On television and journalism. The usefulness of this work is illustrated through a case study of a recent Australian science policy, The chance to change. As this policy went through various iterations and media representations, its naming and structure became more aphoristic. This is the mediatization of contemporary policy, which often results in policy as sound bite. The case study also shows the cross-field effects of this policy in education, illustrating how today educational policy can be spawned from developments in other public policy fields.

Fms-like tyrosine kinase 3 ligand administration overcomes a genetically determined dendritic cell deficiency in NOD mice and protects against diabetes development

A dendritic cell (DC) imbalance with a marked deficiency in CD4(-)8(+) DC occurs in non-obese diabetic (NOD) mice, a model of human autoimmune diabetes mellitus. Using a NOD congenic mouse strain, we find that this CD4(-)8(+) DC deficiency is associated with a gene segment on chromosome 4, which also encompasses non-MHC diabetes susceptibility loci. Treatment of NOD mice with fms-like tyrosine kinase 3 ligand (FL) enhances the level of CD4(-)8(+) DC, temporarily reversing the DC subtype imbalance. At the same time, fms-like tryosine kinase 3 ligand treatment blocks early stages of the diabetogenic process and with appropriately timed administration can completely prevent diabetes development. This points to a possible clinical use of FL to prevent autoimmune disease.

Transitions between routes of benzodiazepine administration among heroin users in Sydney

A sample of 312 heroin users were interviewed regarding their benzodiazepine use. The majority (94%) had used benzodiazepines, 72% in the 6 months prior to interview. Benzodiazepine injecting was common, with 28% of the sample having injected these drugs, 13% in the 6 months preceding interview. Current benzodiazepine injectors showed greater polydrug use, injection-related HIV risk-taking behaviour, criminal involvement, psychological distress and injection-related health problems, as well as poorer general health, and an increased risk of having overdosed than other users of benzodiazepines. Of those subjects who had injected benzodiazepines, 55% were no longer current benzodiazepine injectors. Concern for general health emerged as the most common reason for having made a transition away from injecting, and for being likely to make such a transition.