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J D Graham

Publications and source records attributed to J D Graham.

At least 37 records · Page 2Linked to original sources
PubMed1999

Towards system-wide strategies for reducing adverse drug events.

Despite the best efforts of committed health-care workers, there are many adverse drug events (ADE). A large proportion of ADE arise from system factors, either directly (e.g. poor equipment design) or indirectly (e.g. inappropriate rostering of staff). This paper represents the proceedings of a workshop focus group that deliberated on priority health-system issues identified as requiring action in order to minimise the risks of ADE. Major issues canvassed were the gathering of appropriate and useful data about ADE, the dissemination of information to professionals and consumers, and effective communication across groups of professionals, and between professionals and consumers. A number of recommendations were put forward as important first steps in addressing these issues.

Australia↗
PubMed1999

Factors associated with planned avoidance of alcohol-impaired driving in high-risk men.

OBJECTIVE: This study examines the factors associated with planning to avoid alcohol-impaired driving and successful avoidance in high-risk young men. METHOD: A targeted telephone survey was conducted with male drivers aged 21-35 years who consume alcohol and live in areas of the country where alcohol-related traffic fatalities occur frequently (N = 750). Heavy episodic drinking drivers (i.e., report driving after consuming five or more drinks) were oversampled (N = 230). Respondents were surveyed to assess their attitudes, behavior and social support regarding drinking-driving. RESULTS: Multiple logistic regression revealed that men who believe they can consume six drinks or more before it is too dangerous for them to drive were 45% less likely to report planning to avoid drinking-driving. Men who believe they can drive safely after heavy episodic drinking were 61% less likely to be successful in avoiding drinking-driving. Having friends who disapprove of driving after heavy episodic drinking and believing a close friend would be successful in preventing drinking-driving were significantly associated with making plans to avoid drinking-driving, although this association was less strong for successful avoidance. Men who had their wife/girlfriend along when they were out drinking were two and one-half times more likely to make plans to avoid drinking-driving. The presence of a wife or girlfriend was an even stronger predictor (multivariate odds ratio = 3.74) of successful avoidance. CONCLUSIONS: Attitude and social factors are associated with drinking-driving avoidance in a group of young men at risk for alcohol-related driving fatalities. Friends and wives/girlfriends appear to influence drinking-driving avoidance behavior in high-risk drinking drivers.

Adult↗
PubMed1999

The effect of passenger airbags on child seating behavior in motor vehicles.

Objective. The purpose of this study was to determine the effect of the presence of passenger airbags on places where children sit when traveling in motor vehicles. Methodology. An observational and driver interview survey of 503 passenger vehicles was conducted in five New England states at randomly selected long- and short-distance travel sites during the summer of 1998. Each vehicle was occupied by at least 1 child <13 years of age. Seating position, vehicle information, and driver and passenger characteristics were collected. Logistic regression analysis was used to identify the association between the presence of passenger airbags in vehicles and the seating positions of children. Results. Controlling for the effects of the driver and vehicle characteristics, children <13 years of age were less likely to be observed riding in the front right seat when a passenger airbag was present in the vehicle (odds ratio:.34; 95% confidence interval:.19-.61). Of the vehicles carrying children, 23% had at least 1 child riding in the front seat. Children rode in the front seat in 17% of vehicles with a passenger airbag, and in 30% of those without a passenger airbag. Half of all vehicles without a teenage or adult passenger carried a child in the front seat. In 91% of vehicles with a child riding in the front seat, there was at least one available seat in the rear. Driver safety belt use, younger child age, and the presence of an adult passenger in the vehicle were all associated with children being seated in the rear. Conclusions. Some New England drivers are protecting children from the risks of passenger airbags by seating them in the rear. There remains, however, a substantial number of children who are being exposed to the risk of passenger airbag deployment.

Adolescent↗
PubMed1999

Regulation of the expression and activity by progestins of a member of the SOX gene family of transcriptional modulators.

The mammalian testis-determining gene Sry and the related Sox genes define a family of transcriptional regulators widely expressed during embryogenesis. Tightly controlled temporal profiles of expression are a feature of the Sox gene family and may be required for initiation of a cascade of gene expression, yet the molecular mechanisms that control Sox gene expression are unknown. We now show that human SOX4 is expressed in the normal breast and in breast cancer cells. In these cells SOX4 is a progesterone-regulated gene, the expression of which is increased by progestins, leading to a marked increase in SOX-mediated transcriptional activity. Treatment of T-47D breast cancer cells with the synthetic progestin ORG 2058 directly increased SOX4 transcription, resulting in a 4-fold increase in SOX4 mRNA levels within 4 h of treatment. No effect of ORG 2058 was noted on other SOX genes measured, nor were other hormone-regulated HMG box proteins detected in this system, suggesting that the observed ability of progestin to increase SOX mRNA expression was confined to SOX4. The increase in SOX4 transcription was reflected in increased SOX4 protein expression, as progestin treatment of T-47D cells transfected with a SOX-responsive reporter resulted in a marked increase in reporter gene expression. Progesterone is essential for normal development and differentiation of the female reproductive system, plays an essential role in regulating growth and differentiation of the mammary gland and is required for opposing the proliferative effects of estrogen in specific cell types. The detection of SOX4 expression in the normal and malignant breast and the demonstration that SOX4 expression is under progesterone control suggests that changes in SOX4 gene expression may play a role in commitment to the differentiated phenotype in the normal and malignant mammary gland.

Base Sequence↗
PubMed1999

Driver distance from the steering wheel: perception and objective measurement.

OBJECTIVES: This study assessed the accuracy of driver perceptions of the distance between the driver's nose and the steering wheel of the vehicle as a factor in considering driver disconnection of an airbag contained in the steering wheel for preventing injury to the driver in an accident. METHODS: A cross-sectional survey of 1000 drivers was done to obtain perceived and objective measurements of the distance between the driver's nose and the steering wheel of the vehicle. RESULTS: Of 234 drivers who believed that they sat within 12 inches of the steering wheel, only 8 (3%) actually did so, whereas of 658 drivers who did not believe that they sat within 12 inches of the wheel, 14 (2%) did so. Shorter drivers were more likely than taller ones to both underestimate and overestimate their seating distance. CONCLUSIONS: Considerable misperception of drivers' distance from the wheel indicates that drivers should objectively measure this distance.

Adolescent↗
PubMed1998

Where children sit in motor vehicles: a comparison of selected European and American cities.

OBJECTIVES: To ascertain whether there are differences in child seating location between selected cities in the US and continental Europe, and if differences exist, to ascertain what factors predict them. SETTING: Boston and New Orleans, which have no laws regarding child seating location, and Paris, Frankfurt, and Brussels, which for approximately 20 years have had laws requiring children under the ages of 10 or 12 to sit in the rear. METHODS: Observations were made in the first quarter of 1997 at several locations in or near each city. The vehicle seating capacity, total number of occupants, the seating location of adults and children, and driver shoulder belt use were recorded for each vehicle with at least one child. The predictors of a vehicle having a child in the front were estimated using logistic regression. RESULTS: Data on 5501 children riding in 3778 vehicles were collected. Adjusting for differences in vehicle seating capacity, occupant mix, and driver shoulder belt use, vehicles in the European cities are significantly less likely to have a child in the front seat than vehicles in the American cities. CONCLUSIONS: Cities with no history of laws prohibiting children from sitting in the front, vehicles with low seating capacity, vehicles with no adult (other than the driver) or many child passengers, and unbelted drivers were associated with a higher likelihood of children riding in the front seat. It is feasible for a society to insist, through custom and/or law, that children sit in the back seat.

Automobiles↗
PubMed1998

Evaluating the cost-effectiveness of clinical and public health measures.

Cost-effectiveness analysis, an analytic tool that expresses as a ratio the cost of obtaining an additional unit of health outcome, can help decision makers achieve more health protection for the same or less cost. We characterize the state of the cost-effectiveness analysis literature by reviewing how this technique is applied to various clinical and public health interventions. We describe the results of cost-effectiveness analyses for over 40 interventions to reduce cancer, heart disease, trauma, and infectious disease. The cost-effectiveness ratios for these interventions vary enormously, from interventions that save money to those that cost more than $1 million per year of life gained. The methods used to derive the cost-effectiveness ratios also vary considerably, and we summarize this variation within each health area. Greater uniformity of analytical practice will be necessary if cost-effectiveness analysis is to become a more influential tool in debates about resource allocation.

Communicable Disease Control↗
PubMed1998

Reducing risks to children in vehicles with passenger airbags.

This review examines the risk that passenger airbags pose for children and discusses behavioral and technologic measures aimed at protecting children from airbag deployment. Although airbags reduce fatal crash injuries among adult drivers and passengers, this safety technology increases mortality risk among children younger than age 12. The magnitude of the risk is multiplied when children are unrestrained or restrained improperly. As new vehicles are resold to buyers who tend to be less safety-conscious than new car owners, the number of children endangered by passenger airbag deployment may increase. For vehicles already in the fleet, strong measures are required to secure children in the rear seat and increase the proper use of appropriate restraint systems through police enforcement of laws. One promising strategy is to amend child passenger safety laws to require that parents secure children in the rear seats. For future vehicles, a mandatory performance standard should be adopted that suppresses airbag deployment automatically if a child is located in the front passenger seat. Other promising improvements in airbag design also are discussed. Major changes in passenger airbag design must be evaluated in a broad analytical framework that considers the welfare of adults as well as children.

Adult↗
PubMed1997

The cost-effectiveness of air bags by seating position.

CONTEXT: Motor vehicle crashes continue to cause significant mortality and morbidity in the United States. Installation of air bags in new passenger vehicles is a major initiative in the field of injury prevention. OBJECTIVE: To assess the net health consequences and cost-effectiveness of driver's side and front passenger air bags from a societal perspective, taking into account the increased risk to children who occupy the front passenger seat and the diminished effectiveness for older adults. DESIGN: A deterministic state transition model tracked a hypothetical cohort of new vehicles over a 20-year period for 3 strategies: (1) installation of safety belts, (2) installation of driver's side air bags in addition to safety belts, and (3) installation of front passenger air bags in addition to safety belts and driver's side air bags. Changes in health outcomes, valued in terms of quality-adjusted life-years (QALYs) and costs (in 1993 dollars), were projected following the recommendations of the Panel on Cost-effectiveness in Health and Medicine. PARTICIPANTS: US population-based and convenience sample data were used. MAIN OUTCOME MEASURE: Incremental cost-effectiveness ratios. RESULTS: Safety belts are cost saving, even at 50% use. The addition of driver's side air bags to safety belts results in net health benefits at an incremental cost of $24000 per QALY saved. The further addition of front passenger air bags results in an incremental net benefit at a higher incremental cost of $61000 per QALY saved. Results were sensitive to the unit cost of air bag systems, their effectiveness, baseline fatality rates, the ratio of injuries to fatalities, and the real discount rate. CONCLUSIONS: Both air bag systems save life-years at costs that are comparable to many medical and public health practices. Immediate steps can be taken to enhance the cost-effectiveness of front passenger air bags, such as moving children to the rear seat.

Adult↗
PubMed1997

Whole body doses from linear accelerator-based stereotactic radiotherapy.

PURPOSE: The objective of this work was to measure whole body radiation doses in a humanoid phantom from linear accelerator-based cranial stereotactic radiosurgery/therapy (SRS/T), using different beam arrangements. METHODS AND MATERIALS: A standard noncoplanar five-arc beam arrangement and a four-arc technique without a sagittal arc were used to deliver 20 Gy in a single fraction to a midline spherical target volume in the corpus callosum region of an Alderson-Rando anthropomorphic phantom using (i) a 20-mm and (ii) a 40-mm circular collimator. Whole body dose measurements were made using lithium fluoride thermoluminescent dosimetry. Whole body isodose plots in the sagittal and coronal planes and organ doses were compared for the two arcing beam arrangements. An ionization chamber was used to record the exit dose at intervals along the length of the phantom at midline and 4.5 cm off-axis for (i) a single fixed field and (ii) a solitary 90 degrees sagittal arc using a 40-mm circular collimator. RESULTS: The sagittal arc was the major contributor to neck and trunk doses when the five- and four-arc arrangements were compared, with fourfold greater thyroid dose. The gonad dose was increased by the sagittal arc, but was largely due to leakage radiation. The dose from a fixed field exiting down the long axis of the phantom was tenfold greater than that from a solitary 90 degrees sagittal arc. When the fixed field or arc traversed the lung or exited through the pharynx and major upper airways, the dose measurements below the diaphragm were 30-40% higher than those along the exit path of maximum soft tissue density. CONCLUSION: When SRS/T is used in nonmalignant conditions such as cranial arteriovenous malformations or benign tumors the exit paths of arcing beams or fixed fields should be taken into account when deciding upon the final treatment plan. Such consideration should minimize the risk of radiation-induced malignancy, notably in the thyroid gland of younger patients.

Particle Accelerators↗
PubMed1997

Young male drinkers and impaired driving intervention: results of a U.S. telephone survey.

The present study examines the role of interveners in the driving behavior of a group of drivers at higher risk for involvement in a fatal, alcohol-related motor vehicle accident than the general population, based on their demographic characteristics. The sample consisted of men, aged 21-34 years, living in areas where alcohol-involved motor vehicle fatalities most commonly occur. More than one-half (55%) of these men reported having been the target of an intervention to prevent them from drinking and driving. The variables most strongly associated with having been the target of an intervention were: involvement in an accident after drinking; frequency of driving after drinking too much to drive safely; binge drinking; reporting that it takes ten or more drinks to feel drunk. Age, total alcohol consumption and the relationship between the target and the intervener predicted intervention success. Persons who have close relationships with drinking drivers, particularly wives/girlfriends, are most likely to be successful in preventing these men from drinking and driving. To the extent they can be encouraged to safely intervene, wives/girlfriends and close friends may be potential targets for messages promoting informal social control of drinking and driving.

Accidents, Traffic↗
PubMed1997

Expression of osteonectin mRNA in human breast tumours is inversely correlated with oestrogen receptor content.

Osteonectin is a secreted glycoprotein which is detected in a number of normal and neoplastic human tissues in vivo. It is an extracellular matrix (ECM)-associated protein which is postulated to regulate cell migration, adhesion, proliferation and matrix mineralisation and previous reports suggest that it may be modulated by steroid hormones in target tissues. The aim of this study was to measure osteonectin mRNA and protein expression in breast tumour biopsies and compare these with oestrogen (ER) and progesterone receptor (PR) levels in the same tumours. An inverse correlation was seen between osteonectin mRNA expression and ER level. Samples with low ER protein expression had a mean osteonectin mRNA level which was almost 4-fold greater than the mean level of expression observed in tumours containing high concentrations of ER protein. This inverse correlation was statistically significant. Despite the strong inverse relationship between osteonectin mRNA levels and tumour ER content, no correlation was seen when osteonectin protein concentration was measured in tumour cytosols on immunoblots and compared to ER and PR levels in the same tumours. However, since it is a secreted protein, osteonectin protein expression may not reflect cellular osteonectin levels in breast tumours. In summary, these data suggest that ER-mediated suppression of osteonectin gene expression may contribute to the less aggressive characteristics associated with receptor-positive tumours and that loss of ER expression may lead to over-expression of osteonectin and contribute to a poorer differentiated, more invasive phenotype.

Blotting, Northern↗
PubMed1996

Progesterone receptor A and B protein expression in human breast cancer.

The human progesterone receptor (PR) is a ligand-activated nuclear transcription factor which mediates progesterone action in target tissues. Two PR proteins, PR A (81-83 kDa) and PR B (116-120 kDa), have been described and different physiological activities ascribed to each on the basis of in vitro studies, suggesting that their ratio of expression may control progesterone responsiveness in target cells. Presence of PR in breast tumors is an important indicator of likely responsiveness to endocrine agents. However, the relative expression of PR A and B in breast cancer has not been described and its clinical significance has not been addressed. We have examined the expression of PR A and B in PR-positive breast tumors and found that while in most tumors PR A and B were expressed in similar amounts there was a broad overall distribution of PR A:B ratio which deviated significantly from a normal log distribution with tumors containing a PR A:B ration greater than 4 being over-represented in the group. Linear regression analysis revealed that high PR A:B ratios, in general, derived from a low concentration of PR B rather than high expression of PR A. PR A:B protein ratios were not correlated with the age of the patient or with total PR concentration. A third PR protein band (PR 78 kDa) was detected which comprised greater than 20% of total PR protein in a quarter of the tumor samples examined. The characteristics of tumors containing PR 78 kDa were not different from the overall group. In summary, in PR-positive breast tumors the ratio of expression of PR A and B proteins is close to unity as is seen in a number of other progestin target tissues. However, a significant proportion of tumors expressed very low levels of PR B and a consequently high PR A:B ration. Although the clinical consequence of this observation is not known, the in vitro findings that PR A may act as a repressor for PR B suggests that tumors containing primarily PR A may identify a subset of patients with low or aberrant response to endocrine agents.

Adolescent↗
PubMed1996

The role of heavy drinking in the risk of traffic fatalities.

Recent studies have identified a "hard core" of drinking drivers who do not fit a "social" drinker profile and may require medical intervention. This article builds on these studies by quantifying the role of heavy drinking in motor vehicle fatalities. Data on male alcohol-involved fatally injured drivers (AIFIDs) were obtained from the U.S. Fatal Accident Reporting System (FARS) for the years 1989-1990 (n = 8876). The AIFIDs were grouped into either a "heavy" or "light" drinking category based on drinking behaviors inferred from prior driving records and blood alcohol concentrations (BAC). The majority of male AIFIDs were between the ages of 20-39 (70%). Sixty-five percent had a BAC of 150 mg/dl or greater, and 41% had a BAC in excess of 200 mg/dl. AIFIDs with high BACs were more likely to have histories of DUI convictions and license suspensions than AIFIDs with low BACs. According to the study's criteria, 73% percent of the AIFIDs could be classified as "heavy" drinkers. There were no driving variables that differentiated the heavy and light drinker groups, indicating that heavy drinking per se is the primary factor that distinguishes the groups. Male alcohol-involved fatally injured drivers are comprised mostly of heavy drinkers who may suffer from serious drinking problems or alcoholism. Successful interventions may require medical treatment as well as punitive criminal justice policies.

Accidents, Traffic↗