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PubMed2005

Results of an independent evaluation of Project ALERT delivered in schools by Cooperative Extension.

Reported are results of an independent effectiveness study of the Project ALERT drug prevention program implemented in eight Pennsylvania middle schools by outside program leaders employed by Cooperative Extension. In this randomized, 2-cohort longitudinal evaluation, 1,649 seventh-grade students completed a pretest and four waves of posttests over the 2-year program and 1-year follow-up. Project ALERT's effectiveness was tested through a 3-level hierarchical linear model. Analyses failed to yield any positive effects for substance use or mediators for use in the adult or teen-assisted delivery of the curriculum. An extensive set of additional analyses detected no differential program effects by student risk level, gender, school, or level of implementation quality. Potential explanations for outcomes relative to Project ALERT's original effectiveness trial are discussed, as well as implications for future research, including the need to conduct independent effectiveness studies of previously validated programs in a variety of contexts.

Adolescent↗
PubMed1991

The increasing-temperature hot-plate test: an improved test of nociception in mice and rats.

The increasing-temperature hot-plate test has several advantages compared to the conventional hot-plate test, but available equipment has been impractical and restricted with regard to stimulus control. We now describe an apparatus consisting of an aluminum plate that is heated and cooled by Peltier elements in contact with its lower surface. Several plates can be used simultaneously, individually controlled by electronic proportional feedback circuits. The set temperature of the feedback circuit is controlled by a computer program run on an IBM XT-compatible PC, so that a linear increase in temperature is achieved. Experiments were performed using rats and mice, with hindpaw licking as an end-point criterion. Experiments with various heating rates showed that 3.0 degrees C/min is the lowest rate that can be applied without signs of stress in the animals. On the basis of the recorded data, nociceptive temperature thresholds were calculated to be approximately 44.5 degrees C for both rats and mice. Inspection of the paws after analgesic treatment and exposure to different end-point temperatures suggested that a cutoff temperature of 50 degrees C should be employed to minimize tissue damage. Testing at ambient temperatures of 18 degrees and 28 degrees C yielded similar results for rats, whereas mice responded at significantly higher plate temperatures in the colder environment. Dose-related antinociceptive effects were demonstrated for morphine and paracetamol in both species. The results confirm that the increasing-temperature hot-plate test is a valuable test of nociception, which is also suitable for demonstrating the antinociceptive effects of nonopioid analgesics. The test may also be used to estimate the nociceptive temperature threshold.

Acetaminophen↗
PubMed1978

Least-squares method for restriction mapping.

A least-squares procedure has been developed to aid in deriving restriction-fragment maps once the order of cutsites has been determined. A computer program which carries out this method can be used to map either linear or circular molecules.

Chromosome Mapping↗
PubMed2004

Child protection: a neglected area of pediatric residency training.

BACKGROUND: Child maltreatment is prevalent in Canadian society, and medical professionals are frequently required to provide care in these cases. Physician knowledge and training in child protection have been questioned. This study examined the experience, perceived adequacy of training, and perceived competency of Canadian pediatric residents in child protection. METHODS: Structured questionnaires were sent to child protection program directors (CPPDs), pediatric program directors (PPDs) and pediatric residents at the 16 Canadian pediatric academic centers. Data were analyzed using descriptive statistics, chi(2)-analyses, a Mann-Whitney test, and linear regression. RESULTS: Responses were obtained from 15 of 16 CPPDs, all 16 PPDs, and 190 of 348 (54.6%) residents. All programs provided didactic teaching sessions. Only 3 programs had mandatory clinical rotations, 9 programs offered clinical electives, and 7 programs did not offer any specific clinical experience in child protection. Half of the residents had seen 5 or fewer cases of maltreatment. Residents and program directors most commonly rated the training as "somewhat adequate, needs improvement" with a significant minority rating it as "poor, inadequate." Residents' self-rating of competency was positively associated with number of years of training and number of cases of maltreatment seen. Almost all residents (92%) felt that they needed further training in child protection, including 85% of graduating residents. Some of the residents (16.4%) did not anticipate dealing with child protection cases as practicing pediatricians. CONCLUSIONS: Canadian pediatric residents receive little exposure and limited training in child abuse and neglect. As a result, even senior pediatric residents feel poorly trained. These results highlight the need to establish effective training programs for residents in child protection.

Attitude of Health Personnel↗
PubMed1984

Reversed-phase ion-pair high-performance liquid chromatographic procedure for determination of histamine and its metabolites in rat urine.

A reversed-phase ion-pair high-performance liquid chromatographic procedure for quantitative determination of histamine and its metabolites in rat urine is described. This method allows simultaneous analysis of five major histamine metabolites. Good separations were obtained by using 1-pentanesulfonic acid as the ion-pair reagent. A gradient elution program was used; the total elution time was less than 22 min. Linear standard curves with high correlation coefficients were obtained. This procedure has the advantage of requiring little sample preparation time and handling, and therefore maximizes the recovery of metabolites.

Animals↗
PubMed1999

Inhibition kinetics of human serum butyrylcholinesterase by Cd2+, Zn2+ and Al3+: comparison of the effects of metal ions on cholinesterases.

Butyrylcholinesterase (BChE, EC 3.1.1.8) has been purified about 6600-fold from human serum with a procedure including ammonium sulfate fractionation (55-70%) with acid step at pH 4.5 and procainamide-Sepharose 4B affinity chromatography. The purified enzyme exhibited negative cooperativity with respect to butyrylthiocholine (BTCh) binding at pH 7.5. Ks was found to be 0.128 +/- 0.012 mM. Inhibition kinetics of the enzyme by Cd2+, Zn2+ and Al3+ were studied in detail. The 1/v vs 1/[BTCh] plots in the absence (control plot) and in the presence of different concentrations of cations intersected above 1/[BTCh]-axis. The data were analyzed by means of a nonlinear curve fitting program. The results demonstrated that all of the three cations are the linear mixed-type inhibitors of BChE. Ca2+ and Mg2+ had no effect on the enzyme activity in the experimental conditions. But when the enzyme was inhibited by 0.5 mM Cd2+ or Zn2+, Ca2+ and Mg2+ partially reactivated the inhibited allosteric form of BChE. Results were compared with data obtained from brain BChE purified from sheep.

Allosteric Site↗
PubMed1994

The primary treatment trial: changes in the visual field analysis by computer-assisted perimetry.

Computer-assisted perimetry was performed 6-monthly on patients entered into the Primary Treatment Trial using the 30-2 program. Those patients with a minimum of five visual fields had pointwise linear regression analysis (Progressor) carried out. Two consecutive slopes significant at the 0.05 level were taken as evidence for change, either improvement or worsening. Forty-eight patients in the surgery group, 40 in the medical group and 20 in the laser group were suitable for analysis. A comparison of the eyes showing 'improvement' or 'worsening' in the surgery and medicine groups showed no difference between them. This lack occurred despite a significant difference in intraocular pressure between the two groups. The reasons for this lack of difference are discussed.

Diagnosis, Computer-Assisted↗
PubMed2000

Multi-channel compression and speech intelligibility in industrial noise.

This study examined how various forms of compression affect speech intelligibility in moderately high levels of industrial noise. Thirteen listeners with high-frequency sensorineural hearing loss were fit with a digital hearing aid programmed to operate in three modes of compression: compression limiting, compression of low frequencies only (BILL), and compression of high frequencies only (TILL). For each of these conditions, listeners attempted to recognize CID W-22 monosyllabic words delivered in a background of recorded industrial noise. Word recognition was also measured in quiet for the compression-limiting condition. The highest word identification scores were obtained in quiet (80.9%). Of the three conditions in which background noise was present, the mean score was highest for TILL compression (52.4%), and lowest for BILL (39.7%). Representative time-weighted average (TWA) exposures for each of the aided noise conditions were determined by means of a procedure outlined previously by the first author. The projected 8-hour amplified TWA with the hearing aid programmed to the TILL configuration was 94 dBA, whereas TWAs for the linear and BILL configurations were each 104 dBA. Thus, the highest intelligibility and lowest noise exposures were obtained with the aid in the TILL mode.

Adult↗
PubMed1998

Development of ET(B) selective agonists: solution structure of a linear endothelin-1 analogue, ET-1 [Cys(Acm)(1,15), Ala3, Leu7, dAsp8, Aib11].

The solution structure of a synthetic ET(B) selective agonist, ET-1[Cys(Acm)(1,15), Ala3, Leu7, dAsp8, Aib11] has been solved by 1H NMR and molecular modelling studies. Such solution structures of linear modified peptides in aqueous methanol are being used in an ongoing program of research designed to assist in an understanding of the basic structural requirements for the biological activity of vasoconstrictors. The resulting structure of this peptide is characterised by an alpha-helical conformation between residues Leu6-His16 and by N- and C-termini which assume no defined conformation. A knowledge of the solution structures of this and related peptides, which are ET(B) selective agonists, are proving to be important in the understanding of how they interact with the ET(B) receptor.

Amino Acid Sequence↗
PubMed2005

Long-term evaluation of required coursework in palliative and end-of-life care for medical students.

BACKGROUND: In response to the nationwide need for improved care of patients at end of life, our medical school implemented approximately 20 hours of mandatory coursework on the care of dying patients for all students, with satisfactory completion required for graduation. OBJECTIVE: We now report a long-term evaluation of this coursework. DESIGN/SUBJECTS/MEASUREMENTS: A 74-item questionnaire concerning attainment of palliative care and other medical school course objectives, postgraduate practice encounters with patients at end of life, and postgraduate behaviors in palliative care was mailed to all students who graduated from our medical school in 2000, 2001, and 2002. Responses were graded by a Likert-type scale. Additionally, the Association of American Medical Colleges Medical School Graduation Questionnaire (AAMC/GQ) reports for all schools and for our medical school were queried for data regarding palliative care. RESULTS: The return rate of the questionnaire was 54%. The respondents perceived the training to be valuable and effective. They displayed good postgraduate palliative care practices such as choosing to use opiates other than meperidine for pain in the end-of-life setting. Fifty-three percent of the respondents reported that dying patients were often or frequently under their care since graduation. Despite evidence for the efficacy of the training, the respondents perceived that preparedness in certain palliative care domains was somewhat below preparedness in benchmark medical school competencies such as assessment/management of hypertension and diabetes. The AAMC/GQ surveys indicated that for the years 2000-2002, at least 20% more of our graduates perceived that their training in pain management and palliative care was adequate than did all other medical students graduating nationwide. CONCLUSIONS: The evaluation provides support for the conclusion that mandatory training in palliative and end-of-life care is effective, perceived to be valuable, and contributes to good palliative and end-of-life care practices in our graduates. Furthermore, the training meets a significant demand in our graduates' clinical practice: end-of-life care. However, expanded medical school emphasis and curriculum hours are still needed for palliative care topics, because preparedness in palliative care skills was perceived to be inferior to benchmark medical skills. To our knowledge, this is the first report of a rigorous summative evaluation of the efficacy of required coursework in palliative and end-of-life care in a U.S. medical school curriculum.

Adult↗
PubMed2002

Tclass: tumor classification system based on gene expression profile.

A method that incorporates feature selection into Fisher's linear discriminant analysis for gene expression based tumor classification and a corresponding program Tclass were developed. The proposed method was applied to a public gene expression data set for colon cancer that consists of 22 normal and 40 tumor colon tissue samples to evaluate its performance for classification. Preliminary results demonstrated that using only a subset of genes ranging from 3 to 10 can achieve high classification accuracy.

Colonic Neoplasms↗
PubMed1995

The impact of respite use on nursing home placement.

The results of experimental studies of the effects of respite care have been difficult to interpret because researchers have lacked experimental control over who actually received the treatment. Data from one such study are reanalyzed, focusing on the linear relationship between amount of respite use and probability of nursing home placement at the end of the treatment period. The results indicate a significant negative relationship between amount of respite use and nursing home placement.

Aged↗
PubMed1995

Analysis of cancer rates using excess risk age-period-cohort models.

BACKGROUND: Recently the age-period-cohort (APC) model has become a popular epidemiological tool. However, it is well known that the model suffers from the identifiability problem. The simple multiplicative formulation of the model in terms of the age, period, and cohort variables without resorting to the underlying biology also casts doubt on the interpretability of the model parameters. METHODS: Excess risk APC models for cancers are developed based on carcinogenesis processes in human populations. These models have the beneficial feature of biological plausibility and do not suffer from the identifiability problem. Apart from the age, period, and cohort effects, a new kind of effect, the impact effect, is also introduced into the models. A computer program has been developed to fit the models which contain non-linear as well as restricted parameters. RESULTS: Two published mortality datasets are used to demonstrate the methodology. The proposed models fit better than the conventional APC model in both examples. CONCLUSIONS: Despite all the merits of the proposed models, several statistical issues should be investigated further before accepting this methodology as a general data-analytical tool.

Adult↗
PubMed2003

Intersite consistency as a measurement of programmatic evaluation in a medicine clerkship with multiple, geographically separated sites.

PURPOSE: This study introduces "intersite consistency" as a measurement of programmatic evaluation and demonstrates its feasibility and construct validity. METHOD: Student data in our multisite, geographically separated clerkship were collected prospectively over a ten-year period (1990-2000). We calculated mean scores for each clerkship measurement and analyzed these data on both a yearly and a 10-year cumulative basis. Analyses of variance (ANOVA) and linear regression were used for statistical analysis. RESULTS: Data for 1,632 (98%) students were included in our study. During this ten-year study period, we had 22 different on-site clerkship directors at seven clerkship sites. ANOVA and linear regression of year-to-year and cumulative data did not demonstrate an effect of site on student outcomes. CONCLUSIONS: Intersite consistency can be used as one measure of programmatic evaluation for multisite clerkships.

Analysis of Variance↗
PubMed1999

Application of the ambulatory care groups in the primary care of a European national health care system: does it work?

BACKGROUND: Ambulatory Care Groups (ACGs), a US case-mix system that uses the patient as the unit of analysis, is particularly appropriate for health care systems in which physicians serve a defined list of patients. OBJECTIVE: To determine the extent to which the categorization of patients according to ACGs would account for the utilization of primary care services in a national health care system within the European Union. METHODS: Of all subjects continuously assigned to 9 physicians from public primary health care centers in Bizkaia, Basque Country (Spain) over a 12-month period, those visited at least once (n = 9,093) were included. According to the subject's age, sex, and ICD-9-CM diagnoses assigned during a year of patient-provider encounters, patients were classified by means of the ACGs system. RESULTS: Multiple linear regression analyses indicated that age and sex did not explain more than 7.1% of the variance in annual visits made by adults and 25.7% by children to primary care physicians. However, the r2 adjusted to the ACGs model was 50% and 48%, respectively, and even higher, that is 58% and 64% for another component of the system, the Ambulatory Diagnostic Groups (ADGs). CONCLUSIONS: Those results support the inadequacy of using the patient's age and sex alone to estimate physicians' workload in the primary health setting and the need to consider morbidity categories. The ACGs case-mix system is a useful tool for incorporating patients' morbidity in the explanation of the use of primary health care services in a European national health system.

Adolescent↗
PubMed1997

Self-assessed bleeding and plaque as methods for improving gingival health in adolescents.

The aim of this longitudinal study was to compare the effectiveness, in terms of cognitive and clinical changes, of two oral self-care promoting interventions based on a self-assessment of bleeding from gums or of presence of plaque. Adolescent students (age 14.0 + 0.7 years) from two health districts in Helsinki, Finland, participated in this one-year study. The self-assessment of bleeding group (n = 172) recorded bleeding during tooth brushing and inter-proximal cleaning with toothpicks on a single session. The self-assessment of plaque group (n = 156) recorded the presence of plaque with disclosing dye. Both programmes resulted in comparable clinical improvement in bleeding on probing over 9 months. Increased awareness of gingivitis was associated with clinical improvement. The subjects' socio-economic background, baseline gingival health status and age were statistically significantly associated with gingival health improvement during the follow-up. The results support earlier reports on self-assessment and suggest that both self-assessment approaches are beneficial for promoting gingival health in adolescents.

Adolescent↗
PubMed2001

Reverse engineering of metabolic pathways from observed data using genetic programming.

Recent work has demonstrated that genetic programming is capable of automatically creating complex networks (such as analog electrical circuits and controllers) whose behavior is modeled by linear and non-linear continuous-time differential equations and whose behavior matches prespecified output values. The concentrations of substances participating in networks of chemical reactions are also modeled by non-linear continuous-time differential equations. This paper demonstrates that it is possible to automatically create (reverse engineer) a network of chemical reactions from observed time-domain data. Genetic programming starts with observed time-domain concentrations of input substances and automatically creates both the topology of the network of chemical reactions and the rates of each reaction within the network such that the concentration of the final product of the automatically created network matches the observed time-domain data. Specifically, genetic programming automatically created metabolic pathways involved in the phospholipid cycle and the synthesis and degradation of ketone bodies.

Biomedical Engineering↗
PubMed2002

Assessing radiology resident reporting skills.

PURPOSE: To develop an Objective Structured Clinical Examination for assessing the reporting skills of radiology residents. MATERIALS AND METHODS: The approach used in this study derives from performance-based assessment, that is, tests in which actual performance of a skill is observed and measured. For this task, 29 radiology residents and five faculty members (n = 34) independently dictated reports regarding a set of 20 cases with radiographs in 1 hour. The task was performed in a controlled environment. Data were analyzed by using analysis of variance and tests for linear trends, with the expectation of increasing performance with increasing experience. RESULTS: Significant relationships were observed between subjects' experience and the mean number of cases completed (F = 4.46, P =.006), the mean number of well-specified impressions (F = 5.84, P =.001), and the mean number of urgent or discrepant findings noted (F = 3.67, P =.015). Results also demonstrated a clear linear trend of increasing performance with increasing experience with each variable (P =.002, <.001, and.002, respectively, for t tests with polynomial contrasts). CONCLUSION: The significant linear trends indicate that reporting skills increase with increasing experience in the program. This finding supports the validity of the measurement. The Objective Structured Clinical Examination provides a means of assessing radiology resident reporting skills.

Clinical Competence↗