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Biomedical subjects

J A Bowman

Publications and source records attributed to J A Bowman.

At least 19 recordsLinked to original sources
PubMed2001

C--N bond formation on addition of aryl carbanions to the electrophilic nitrido ligand in TpOs(N)Cl(2).

The osmium(VI) nitrido complex TpOs(N)Cl(2) (1) has been prepared from K[Os(N)O(3)] and KTp in aqueous ethanolic HCl. It reacts rapidly with PhMgCl and related reagents with transfer of a phenyl group to the nitrido ligand. This forms Os(IV) metalla-analido complexes, which are readily protonated to give the analido complex TpOs(NHPh)Cl(2) (4). The nitrido-phenyl derivatives TpOs(N)PhCl and TpOs(N)Ph(2) react more slowly with PhMgCl and are not competent intermediates for the reaction of 1 with PhMgCl. Reactions of 1 with alkyl- and arylboranes similarly result in transfer of one organic group to nitrogen, leading to isolable borylamido complexes such as TpOs[N(Ph)(BPh(2))]Cl(2) (11). This is an unprecedented insertion of a nitrido ligand into a boron--carbon bond. Hydrolysis of 11 gives 4. Mechanistic studies suggest that both the Grignard and borane reactions proceed by initial weak coordination of Mg or B to the nitrido ligand, followed by migration of the carbanion to nitrogen. The hydrocarbyl group does not go to osmium and then move to nitrogen--there is no change in the atoms bound to the osmium during the reactions. It is suggested that there may be a general preference for nucleophiles to add directly to the metal--ligand multiple bond rather than binding to the metal first and migrating. Ab initio calculations show that the unusual reactivity of 1 results from its accessible LUMO and LUMO + 1, which are the Os = N pi* orbitals. The bonding in 1 and its reactivity with organoboranes are reminiscent of CO.

Journal Article↗
PubMed2001

Structure and sequence conservation of a putative hypoxia response element in the lactate dehydrogenase-B gene of Fundulus.

Many aquatic habitats are characterized by periodic or sustained episodes of low oxygen concentration, or hypoxia, and organisms that survive in these habitats do so by utilizing a suite of behavioral, physiological and biochemical adjustments to low oxygen (1-3). In the killifish Fundulus heteroclitus, one response to prolonged exposure to hypoxia is an increase in the activity of lactate dehydrogenase-B (LDH-B), the terminal enzyme of anaerobic glycolysis, in liver tissue (4). An increase in glycolytic enzyme activity also occurs in mammalian cells during hypoxia, a process due, in part, to increased rates of gene transcription mediated by the hypoxia-inducible transcription factor, HIF-1 (5). Given that a homolog of HIF-1 has been identified in fish (6), we hypothesized that HIF might be involved in the observed up-regulation of LDH-B in F. heteroclitus. Herein, we describe the presence of DNA elements in intron 2 of the Ldh-B gene from F. heteroclitus that resemble hypoxia response elements (HRE) describedfor mammalian genes (7-10). Specifically, over a region of approximately 50 base pairs we identified two consensus HIF-1 binding sites, as well as DNA elements that may bind other transcription factors (e.g., cyclic AMP response elements; CRE). We found that these sites were perfectly conserved among geographically diverse populations of F. heteroclitus, as well as being highly conserved among multiple species in the genus Fundulus. The spacing, orientation, and sequence conservation of these putative regulatory elements suggest that they may be functionally involved in the hypoxic regulation of Ldh-B in these fish.

Animals↗
PubMed2000

Can compliance with nonpharmacologic treatments for cardiovascular disease be improved?

OBJECTIVE: To critically review the literature regarding the effectiveness of interventions aimed at improving cardiovascular patient compliance with nonpharmacologic treatments. METHODS: We searched Medline, Healthplan, and Psychlit from 1985 to 1996; searched the bibliographies of located studies; contacted Australian government departments and nongovernment organizations; and two experts examined the resulting study list. We selected 27 studies, which randomly allocated patients to groups and were published in English, and we evaluated interventions aimed at increasing compliance with nonpharmacologic treatments for cardiovascular disease. These trials were critically appraised against eight methodologic criteria and, subsequently, classified as of good, fair, or poor quality. Information about target groups, samples, trial intervention strategies and their effectiveness were extracted from the 18 good- and fair-quality trials. Interrater reliability was high on the 20% of references that were double-coded. The 18 studies reviewed described the effectiveness of 27 intervention strategies at improving compliance with dietary, smoking-cessation, exercise, weight-loss, stress-reduction, general lifestyle, relaxation, and blood pressure screening programs. RESULTS: Tentative recommendations were made for or against most trial strategies: partner-focused and structural strategies showed the most consistent benefits, physician-focused strategies were unanimously unsuccessful, and patient-focused strategies were of mixed benefit. CONCLUSIONS: The methodologic quality of many of the located trials was less than optimal. Therefore, further good-quality, randomized trials are necessary to clarify the effectiveness of those strategies identified as potentially useful in this review.

Cardiac Rehabilitation↗
PubMed1999

A critical review of interventions to increase compliance with medication-taking, obtaining medication refills, and appointment-keeping in the treatment of cardiovascular disease.

BACKGROUND: The aim of this study was to critically review the literature regarding interventions to improve cardiovascular patients' compliance with medication-taking, obtaining medication refills, or appointment keeping. METHODS: The search for relevant randomized trials involved searching the Medline, Healthplan, and Psychlit databases from 1985 to 1996; searching the bibliographies of located studies; contacting Australian government departments, non-government organizations, and pharmaceutical companies; and ultimate review of the resulting list by two field experts. The 33 located trials were critically appraised and classified as being of good, fair, or poor methodological quality. Descriptive and effectiveness data were then extracted from the 20 good and fair quality trials. Interrater reliability was high on the 20% of references double-coded. RESULTS: The 20 studies reviewed evaluated the effectiveness of 18 intervention strategies. Tentative recommendations were made for many patient-focused and structural strategies across all three target behaviors. Physician-focused strategies, tested only for appointment keeping, were all tentatively recommended against. CONCLUSIONS: The methodological quality of many of the located trials was less than optimal, prohibiting strong recommendations. Therefore, further good-quality, randomized trials are necessary in order to clarify the effectiveness of those strategies identified as potentially useful in this review.

Adult↗
PubMed1999

SR-related proteins and the processing of messenger RNA precursors.

The processing of messenger RNA precursors (pre-mRNA) to mRNA in metazoans requires a large number of proteins that contain domains rich in alternating arginine and serine residues (RS domains). These include members of the SR family of splicing factors and proteins that are structurally and functionally distinct from the SR family, collectively referred to below as SR-related proteins. Both groups of RS domain proteins function in constitutive and regulated pre-mRNA splicing. Recently, several SR-related proteins have been identified that are associated with the transcriptional machinery. Other SR-related proteins are associated with mRNA 3' end formation and have been implicated in export. We review these findings and evidence that proteins containing RS domains may play a fundamental role in coordinating different steps in the synthesis and processing of pre-mRNA.

Animals↗
PubMed1998

Computers in community-based drug and alcohol clinical settings: are they acceptable to respondents?

The use of computer technology is not new in the delivery of health services. Previous studies have assessed the reliability and validity of computerised surveys, relative to pen and paper versions or interviews or the acceptability of computers in a range of treatment settings. Generally, these studies have reported that the reliability, validity and acceptability of computer surveys is at least comparable to more traditional survey methods. This study provides evidence for the appropriateness of using computers in community-based drug and alcohol clinical settings, reporting a high level of computer acceptability among clients. The advantages of utilising computers in clinical settings, for researchers and clinicians, are discussed.

Adult↗
PubMed1997

The accuracy of self-reported Pap smear utilisation.

This study assessed the accuracy of self-reported Pap smear utilisation over four different time frames, examining the magnitude of errors in self-report and sociodemographic predictors of accuracy. Self-report data on women's cervical screening was collected by interview in a random household survey (Hunter Region, NSW, Australia), with pathology laboratory data collected by a search of records within laboratories. The magnitude of error in self-report was assessed by comparing it against longer intervals in pathology laboratory data. Sociodemographic predictors of accuracy were explored using chi square analyses. Low values for specificity and positive predictive value across all four time frames indicate a considerable degree of inaccuracy in women's reporting of those instances where, in truth, screening has not occurred. Of women reporting a smear within the last three years, only 61.2% were verified within pathology laboratory records. Allowing women some "leeway" in their reporting, comparing self-report to longer intervals of pathology laboratory data, did not greatly improve the accuracy of reporting, confirming that the magnitude of inaccuracy involved is of real clinical significance. Demographic variables were not related to the accuracy of self-report and, while a woman's certainty of her response was predictive, this had little impact on the measures of agreement. Self-report of Pap smear histories consistently results in over-reporting of screening. Other means of assessing the prevalence of screening may be preferable to self-report. Where self-report data is collected, techniques to improve accuracy should be employed, and care should be taken in comparing screening rates obtained by different methods.

Adolescent↗
PubMed1997

Behavioural alcohol research: new directions or more of the same?

AIM: Despite a large body of literature, a substantial burden of illness related to the abuse of alcohol, as well as significant economic and social costs, persist. As such, a critical examination of the type of research being published in relation to alcohol misuse seems appropriate, particularly since some experts in the field have expressed the view that the current distribution of research types may not be optimal. FINDINGS: The types of research conducted in two separate years, 1983 and 1993, were examined critically. Generally, the types of research conducted in both years was found to be similar: the majority of published alcohol research is behavioural, the majority of published behavioural alcohol research is descriptive and the majority of published behavioural intervention alcohol research represents tertiary prevention studies. Although the reasons for this distribution of research types are undoubtedly numerous and complex, some possible explanations are discussed. CONCLUSIONS: Overall, it is concluded that the current approach to alcohol research may have engendered a distribution of research types which is somewhat less than ideal and that, as such, a new approach may be indicated. Some strategies that may assist in redressing the perceived imbalance are considered.

Alcoholism↗
PubMed1991

The accuracy of Pap smear utilization self-report: a methodological consideration in cervical screening research.

One method used to determine utilization rates of cervical screening is women's self-report. Few studies have assessed the accuracy of this measure--none has been conducted in Australia--although there are a number of reasons for suspecting its validity. This study examined and quantified the accuracy of self-report of Pap smear use among a randomly selected sample of women from an Australian community. Accuracy of Pap smear utilization self-report within a three-year period was assessed by comparison with pathology records. Results indicated that almost half of the women who have not had Pap smears within three years will be missed by a self-report measure of utilization. Some implications for the measurement and use of self-report data are discussed.

Adolescent↗
PubMed1990

General practitioners and the provision of Papanicolaou smear-tests: current practice, knowledge and attitudes.

General practitioners are the main providers of Papanicolaou smear-tests yet, given the current suboptimal rates of cervical screening, it is clear that their full potential as screening providers is not being realized. To date, no information has been available concerning the possible barriers to the provision of Papanicolaou smear-tests by general practitioners. The present study assessed the views of a random sample of NSW general practitioners regarding the value of smear-tests, the most appropriate providers, the recommended screening protocol, and factors that were thought to influence both practitioners' provision and women's utilization of screening. The results indicate a number of changes to the current system which could counter screening barriers such as educational programmes for general practitioners, more female providers and the investigation of alternative services, consensus screening guide-lines, and screening registers and recall systems.

Adult↗
PubMed1988

Assessing women's health needs.

It has been argued that women have specific health needs aside from those of the community as a whole. As a consequence, a move towards increased "earmarked" funding for women's health has occurred. However, some debate exists about the areas of women's health that are most in need of additional funding and about appropriate mechanisms to determine priority areas. The present study explored community perceptions of women's health needs. A sample of 157 women, who had been selected at random, were asked a series of questions about the health and social problems that are experienced by women. The questions assessed the self-reported prevalence of the problems and asked women to nominate those problems which were priorities for them personally, and for Australian women in general. The areas that were identified as priorities by this community survey were compared with those that were identified by means of other methods of needs analysis.

Adolescent↗
PubMed1988

Psychosocial factors related to parental restraint of pre-school children in motor vehicles.

While the use of safety restraints effectively reduces the risk of death or injury in accidents, many children still travel unrestrained in motor vehicles. Compulsory seat belt legislation in Australia increased rates of adult use dramatically, but did not have the same impact with children. In order to understand why levels of children's restraint use remain low, it is necessary to investigate parental factors related to use and non-use of restraints. This study assessed the rates of safety restraint use of parents and their pre-school children, and the sociodemographic, attitudinal and belief characteristics of parents which relate to children's restraint use, using the Health Belief Model as a basis for investigation. Restraint use for adults was substantially higher than for pre-school children. Children were more likely to be restrained if their parents were wearing seat belts, were married, were of high socioeconomic status, did not smoke, engaged in certain other preventive health behaviors on their children's behalf, traveled longer distances to pre-school and provided child seats for their children. In terms of the Health Belief Model, parents of restrained and unrestrained children differed in their evaluation of the "costs" and "benefits" of using restraints for their children, and in health locus of control. Parents of unrestrained children perceived the "costs" of restraint use, in terms of nuisance value, installation difficulty and financial cost, to be high. They were also less likely to believe that they could play a significant role in preventing injury to their children. Implications of these findings for safety restraint campaigns are discussed.

Adolescent↗
PubMed1988

Studies of child safety restraint use in motor vehicles--some methodological considerations.

Despite the effectiveness of safety restraints in reducing the risk of death or injury in motor vehicle accidents, many children still travel unrestrained. Two methodological issues related to child restraint studies which had not been adequately addressed were identified: firstly, the accuracy of parental self-reports of restraint use with their children; and secondly, the consistency of observational data over time. These issues were investigated in the present research. The data indicate that parents' report is inaccurate, suggesting that if self-report measures are used, there is a need to compare them with direct observational measures to obtain information on reporting bias. A single observation of a child's restraint use appears to provide an accurate reflection of restraint use on other occasions in the same setting.

Adolescent↗
PubMed1988

On the dependence of the elasticity and strength of cancellous bone on apparent density.

This paper presents a statistical analysis of the pooled data from a number of previous experiments concerning the dependence of the Young's moduli and strength of cancellous bone tissue upon apparent density. The results show that both the Young's moduli and the strength are proportional to the square of apparent density of the tissue and are therefore proportional to one another. It is shown that the coefficient of proportionality is different for human and bovine tissue. It is concluded that the suggestion of Wolff (Das Gesetz der Transformation der Knochen, Hirschwald, Berlin, 1892) that compact bone tissue is simply more dense cancellous bone tissue is not an accurate statement when only the mechanical properties of these two tissues are considered. It is noted that estimates for the elastic modulus of the individual trabecula of human cancellous bone vary from 1 to 20 GPa and it is suggested that this question needs further study.

Biomechanical Phenomena↗
PubMed1987

Effects of intervention on antibiotic compliance in patients in general practice.

This study used a randomized clinical control design to test first, whether decreasing the complexity of antibiotic regimens resulted in increased compliance and, secondly, whether the added component of written information and behavioural tailoring increased compliance in patients with twice-a-day schedules. Twenty-eight general practitioners who were selected at random and 232 of their patients took part in the study. Patients were allocated at random to receive either doxycycline (one dose a day); co-trimoxazole (two doses a day); amoxycillin (three doses a day); or co-trimoxazole (two doses a day) with a written instruction sheet and advice on how to best fit the tablets into a daily routine. Decreasing complexity of the regimen significantly increased the probability that patients would not miss any doses of the course (absolute compliance: chi 2 = 25.04; df = 2; P less than 0.001). There was also a significant association between complexity and non-compliance at a level which might be clinically significant (chi 2 = 6.78; df = 2; P = 0.03). Written information and behavioural tailoring did not further augment compliance in patients with one- or two-doses-a-day schedules. It was also shown that general practitioners predicted potential non-compliance in patients at a rate no better than would be expected by chance.

Amoxicillin↗
PubMed1987

Analyzing aversiveness of denatonium saccharide and quinine in rats.

Denatonium saccharide is reported to be the most bitter substance currently known. Two experiments comparing the suppressive capabilities of this compound and the more common bitter, quinine, are presented. Analysis indicated that rats preferred to consume denatonium rather than quinine when afforded a choice between the two. Exp. 2 also indicated that the pairing of quinine with vanilla and almond flavors resulted in subsequent refusal of these flavors. Pairing flavors with denatonium did not produce comparable refusals. Caution is expressed with regard to the use of denatonium saccharide as a rodent repellent.

Animals↗
PubMed1987

Interventions in preschools to increase the use of safety restraints by preschool children.

Despite the proven safety value of wearing vehicle safety restraints, people continue to travel without this protection. Legislation requiring the use of safety restraints has been implemented in several countries, including Australia, in an attempt to improve rates of restraint use. In Australia, legislation dramatically increased rates of adult restraint use, yet the rate of restraint use by children remains comparatively low. One of the main reasons for parents not restraining their child is the child's dislike of wearing a restraint, with resultant disruptive behavior. This study compared two interventions implemented within preschools: a coercive intervention aimed at parents and an educational intervention aimed at preschool children. Measures of restraint use were made by direct observation at preschools prior to intervention and again immediately following the 2-week interventions. The safety restraint use of children in the control and coercive intervention groups did not change significantly as a result of intervention. Restraint use of children in the educational intervention group increased 15 percentage points from 60.6% to 75.0%: a significant increase of 25%. This novel intervention approach holds promise as a means of increasing preschool children's use of safety restraints.

Accident Prevention↗