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B Thompson

Publications and source records attributed to B Thompson.

At least 37 records · Page 2Linked to original sources
PubMed2001

Ventilation-perfusion inhomogeneity increases gas uptake in anesthesia: computer modeling of gas exchange.

Ventilation-perfusion (VA/Q) inhomogeneity was modeled to measure its effect on overall gas exchange during maintenance-phase N(2)O anesthesia with an inspired O(2) concentration of 30%. A multialveolar compartment computer model was used based on physiological log normal distributions of VA/Q inhomogeneity. Increasing the log standard deviation of the distribution of perfusion from 0 to 1.75 paradoxically increased O(2) uptake (VO(2)) where a low mixed venous partial pressure of N(2)O [high N(2)O uptake (VN(2)O)] was specified. With rising mixed venous partial pressure of N(2)O, a threshold was observed where VO(2) began to fall, whereas VN(2)O began to rise with increasing VA/Q inhomogeneity. This phenomenon is a magnification of the concentrating effects that VO(2) and VN(2)O have on each other in low VA/Q compartments. During "steady-state" N(2)O anesthesia, VN(2)O is predicted to paradoxically increase in the presence of worsening VA/Q inhomogeneity.

Anesthesia↗
PubMed2001

Effect of ventilation-perfusion inhomogeneity and N(2)O on oxygenation: physiological modeling of gas exchange.

Ventilation-perfusion (VA/Q) inhomogeneity was modeled to measure its effect on arterial oxygenation during maintenance-phase anesthesia involving an inspired mixture of 30% O(2) and either N(2)O or N(2). A multialveolar compartment computer model was constructed based on a log normal distribution of VA/Q inhomogeneity. Increasing the log SD of the distribution of blood flow from 0 to 1.75 produced a progressive fall in arterial PO(2) (Pa(O(2))). The fall was less steep in the presence of N(2)O than when N(2) was present instead. This was due mainly to the concentrating effect of N(2)O uptake on alveolar PO(2) in moderately low VA/Q compartments. The improvement in Pa(O(2)) when N(2)O was present instead of N(2) was greatest when the degree of VA/Q inhomogeneity was in the range typically seen in anesthetized patients. Models based on distributions of expired and inspired alveolar ventilation give quantitatively different results for Pa(O(2)). In the presence of VA/Q inhomogeneity, second-gas and concentrating effects may have clinically significant effects on arterial oxygenation even at "steady-state" levels of N(2)O uptake.

Arteries↗
PubMed2001

Ventilation-perfusion inhomogeneity increases gas uptake: theoretical modeling of gas exchange.

Ventilation-perfusion (VA/Q) inhomogeneity was modeled to measure its effect on gas exchange in the presence of inspired mixtures of two soluble gases using a two-compartment computer model. Theoretical studies involving a mixture of hypothetical gases with equal solubility in blood showed that the effect of increasing inhomogeneity of distributions of either ventilation or blood flow is to paradoxically increase uptake of the gas with the lowest overall uptake in relation to its inspired concentration. This phenomenon is explained by the concentrating effects that uptake of soluble gases exert on each other in low VA/Q compartments. Repeating this analysis for inspired mixtures of 30% O(2) and 70% nitrous oxide (N(2)O) confirmed that, during "steady-state" N(2)O anesthesia, uptake of N(2)O is predicted to paradoxically increase in the presence of worsening VA/Q inhomogeneity.

Models, Biological↗
PubMed2001

Antipsychotic polypharmacy: a survey of discharge prescriptions from a tertiary care psychiatric institution.

OBJECTIVE: To perform a retrospective survey of discharge medications at a tertiary care psychiatric facility and to assess the incidence of antipsychotic polypharmacy. METHOD: This is a retrospective survey that used the Department of Pharmacy's computer database to obtain relevant discharge information on all nongeriatric patients with schizophrenia discharged from Riverview Hospital between November 1, 1996 and October 31, 1998. From a total of 492 eligible patients, 229 met the inclusion criteria and formed the database for the survey. RESULTS: The main finding of the survey was that 27.5% of our discharged patients diagnosed with schizophrenia left our facility on an antipsychotic polypharmacy regimen. Compared with patients discharged on a single antipsychotic, the pooled data revealed a significantly greater use of anticholinergic agents in those patients prescribed an antipsychotic polypharmacy regimen. Further, of the atypical agents, only risperidone showed a statistically significant reduction in dosage when coprescribed with a second antipsychotic. CONCLUSION: Although antipsychotic polypharmacy persists today, as it has over the past 30 years, evidence-based data to support this controversial treatment strategy is lacking. As a result clinicians are relying on their clinical experience, and perhaps intuition, to design antipsychotic polypharmacy treatment protocols. Efforts should be made to replace subjective clinical impression with a more rational approach to antipsychotic polypharmacy--one that is based on pharmacodynamic and pharmacokinetic understanding of drug action.

Adult↗
PubMed2001

Reliability generalization: exploring reliability variations on MMPI/MMPI-2 validity scale scores.

The study utilized the measurement meta-analytic method called "reliability generalization" to examine (a) the typical reliability, (b) the variability of score reliability, and (c) the factors predicting variability of score reliability on the three MMPI validity scales. Across studies the reliability coefficients on the three validity scales ranged from .16 to .93, with the F scale having the most variability, as might be expected. Regression analyses suggested that the age of participant best predicted the variation of reliability coefficients.

Female↗
PubMed2001

Factors related to cancer screening in Hispanics: a comparison of the perceptions of Hispanic community members, health care providers, and representatives of organizations that serve Hispanics.

Hispanics have lower rates of screening for cervical, breast, and colon cancer than non-Hispanics. Activities to increase cancer screening in this population may not be informed by Hispanics, which may have implications for success rates of interventions. In this study, the perceptions about cancer screening behaviors in Hispanics are compared among three groups: a random sample of respondents (75% Hispanic) to a population-based survey, health care providers (primarily non-Hispanic), and representatives of organizations that serve Hispanics (36% Hispanic). While there was agreement that socioeconomic factors were important for cancer screening, differing views were expressed regarding the importance of cultural factors for cancer screening among Hispanics. Interventions developed by those who serve the Hispanic population may be based on inaccurate perceptions about the beliefs and practices of the population served. For effective interventions, it will be necessary to understand the factors important to Hispanics for cancer screening.

Adult↗
PubMed2001

Identifying constituents to participate in a project to control pesticide exposure in children of farmworkers.

Farmers in Washington State use pesticides to control harmful pests that might interfere with the quality of their products. Farmworkers, who are primarily responsible for thinning, harvesting, and other agricultural work, are often exposed to these pesticides and take home pesticide residues on their clothing, shoes, and skin, potentially exposing children in the household to pesticides. We designed a project to reduce children's exposure by using a community organization model. To better understand the community views regarding pesticide exposure, we conducted a qualitative community analysis. Two methods of data gathering were used to collect information. Individual interviews were conducted with some respondents, and small group discussions were held with others. Analysis indicated wide disparity among involved groups in their views on pesticides; however, a number of themes common to the majority of the constituents were identified and discussed with a community planning group. Because of the contention around pesticides, the group recommended every constituent participate in decision making. The group noted it was important to emphasize that the research project could provide scientific information on pesticide exposure to everyone in the Lower Yakima Valley. Our study demonstrates both the widely varying views of different constituents around the issue of pesticide exposure and common themes that can form the basis for collaboration and consensus on approaching the issue.

Adolescent↗
PubMed2000

How much do the general public want to be involved in decisions on implementing water fluoridation?

OBJECTIVE: Test general public view about how much they wish to be involved in water fluoridation implementation decisions. DESIGN: Qualitative research using focus group discussions led by an experienced moderator. SETTING: Among the general public living in three non-fluoridated areas in England. SUBJECTS: Members of the public more than 20 years of age and by social class. RESULTS: General public wish to be informed of water fluoridation plans but do not see themselves as being the appropriate implementation arbiters. CONCLUSIONS: In the public's eyes, it would be inappropriate and unwelcome to delegate to them the decision about whether to fluoridate the public water supply.

Adult↗
PubMed2000

Oncogenic base substitution mutations in circulating leukocytes of normal individuals.

The background frequency of mutations in human tissues is an important issue in cancer susceptibility and genotoxic exposure determinations. Here we report the detection of rare mutant leukocytes containing oncogenic base substitutions of the Harvey-ras, N-ras, and p53 genes by the Needle-in-a-Haystack mutation assay with a sensitivity of one cell in a million. Altogether, we detected and identified 17 independent mutations of 66 separate base site analyses of peripheral blood specimens obtained from 19 apparently normal individuals. Two individuals harbored a substantially increased frequency of mutant cells, representing 9 of the 17 independent mutations found. These results suggest that up to 1 in 10 normal individuals may harbor a significant frequency of oncogenic mutations in circulating leukocytes.

Base Sequence↗
PubMed2000

Localization and physiological regulation of the exocytosis protein SNAP-25 in the brain and pituitary gland of Xenopus laevis.

In mammals, the synaptosomal-associated protein of 25 kDa, SNAP-25, is generally thought to play a role in synaptic exocytosis of neuronal messengers. Using a polyclonal antiserum against rat SNAP-25, we have shown the presence of a SNAP-25-like protein in the brain of the South-African clawed toad Xenopus laevis by Western blotting and immunocytochemistry. Xenopus SNAP-25 is ubiquitously present throughout the brain, where its distribution in various identified neuronal perikarya and axon tracts is described. Western blot analysis and immunocytochemistry also demonstrated the presence of SNAP-25 in the neural, intermediate and distal lobes of the pituitary gland. Intensity line plots of confocal laser scanning microscope images of isolated melanotropes indicated that SNAP-25 is produced and processed in the rough endoplasmatic reticulum and Golgi apparatus, and is associated with the plasma membrane. Immunoelectron microscopy substantiated the idea that SNAP-25 is present in the plasma membrane but also showed a close association of SNAP-25 with the bounding membrane of peptide-containing secretory granules in both the neurohemal axon terminals in the neural lobe and the endocrine melanotropes in the intermediate lobe. Quantitative Western blotting revealed that adapting Xenopus to a dark background has a clear stimulatory effect on the expression of SNAP-25 in the neural lobe and in the melanotrope cells. This background light intensity-dependent stimulation of SNAP-25 expression was confirmed by the demonstration of increased immunofluorescence recorded by confocal laser scanning microscopy of individual melanotropes of black background-adapted toads. On the basis of this study on Xenopus laevis, we conclude that SNAP-25 (i) plays a substantial role in the secretion of a wide variety of neuronal messengers; (ii) functions in the central nervous system but also in neurohormonal and endocrine systems; (iii) acts at the plasma membrane but possibly also at the membrane of synaptic vesicles and peptide-containing secretory granules; (iv) acts not only locally (as in synapses), but at various sites of the plasma membrane (as in the endocrine melanotrope cell); and (v) can be upregulated in its expression by physiological stimuli that increase the extent of the molecular machinery involved in exocytosis.

Animals↗
PubMed2000

Rural Mexican American men's attitudes and beliefs about cancer screening.

INTRODUCTION: Mexican American men are thought to receive fewer cancer screening services for prostate and colon cancer than the general male population; however, little is known about this group. METHODS: A population-based cross-sectional study was conducted to examine the knowledge, beliefs, attitudes, and use of cancer screening services among a sample of high-acculturated Mexican American, low-acculturated Mexican American, and non-Mexican American white men in Washington State. A total of 158 men (127 Mexican American; 31 non-Mexican American white) completed an in-person interview. RESULTS: The Mexican American men were more likely to report employment in agriculture and had completed fewer years of formal education compared with the non-Mexican American men, and were more likely than their non-Mexican American counterparts to have little knowledge about the causes of cancer and the need for cancer prevention practices. Further, the Mexican American men were more likely to report avoidant and fatalistic attitudes about cancer. CONCLUSION: Future research should address variables that are related to the low level of cancer screening among Mexican American men.

Adolescent↗
PubMed2000

Evaluating prevention programs with the Results Mapping evaluation tool: a case study of a youth substance abuse prevention program.

The harmful effects of alcohol and other drug abuse are widespread. Our health care, social service, education and legal systems are strained under the impact of substance abuse, not to mention the economic costs associated with substance abuse. Consequently, effective strategies which prevent substance abuse must be identified and replicated. Yet, user-friendly and cost-effective evaluation tools for community-based substance abuse prevention programs are rare. A recently developed tool that has promise to overcome some of the barriers which exist when evaluating prevention programs is 'Results Mapping'. Results Mapping documents and aims to quantify the contributions of a program to future outcomes of its target population with the intention of making data meaningful at the program and funding agency level. This case study was conducted to assess the feasibility of implementing the Results Mapping evaluation tool for community-based prevention programs. The study assessed qualitatively how well Results Mapping worked for one community-based substance abuse prevention program, as well as how much time and funding it took to implement this new tool. Results suggested that Results Mapping may be a valuable documentation, planning and learning tool, but funding agencies should be cautious about using Results Mapping scores to determine funding allocations.

Adolescent↗
PubMed2000

Durability of tobacco control efforts in the 22 Community Intervention Trial for Smoking Cessation (COMMIT) communities 2 years after the end of intervention.

Funding organizations increasingly want to know that successful interventions are continued after the end of a research project. Assessments of durability are rare and where done do not include the comparison communities. In this study we ascertain what tobacco control activities continued in intervention communities involved in the Community Intervention Trial for Smoking Cessation (COMMIT), a randomized, controlled community trial aimed at adult smokers, and also assessed level of tobacco control activities in the comparison communities. A mailed survey of key informants including paid staff and community volunteers in the 22 COMMIT communities was conducted. Approximately 79% of key informants responded to the survey. Although there was evidence that tobacco control activities were continuing in the intervention communities, there was an equal amount of tobacco control effort in the comparison communities. Within the specific tobacco control intervention areas, only the youth area showed more activity in intervention communities than comparison communities. We conclude that despite a positive trial outcome, differential durability was not achieved. More work needs to be done to assist communities in maintaining proven intervention activities. More study of methods to measure durability is also needed.

Adult↗
PubMed2000

Reliability and validity of scores from the Singer-Loomis Type Deployment Inventory.

This paper focuses on the Singer-Loomis Type Deployment Inventory (SL-TDI), which is an alternative to the Myers-Briggs Type Indicator (MBTI). The SL-TDI utilizes a continuous, non-forced choice format and therefore is a more accurate representation of Jung's personality theory of psychological types. The purpose of the study reported here is to evaluate the reliability and validity of scores from the SL-TDI. Specifically, the goals were to (a) provide estimates of the internal consistency of SL-TDI scores; (b) evaluate the divergent validity of SL-TDI scores by examination of their relationships with the scores on a social desirability responding measure; and (c) examine the test-retest stability of scores from the SL-TDI. Strong support was found for both the reliability and validity of SL-TDI scores.

Adult↗
PubMed2000

Second-order confirmatory factor analysis of the WAIS-III. Wechsler Adult Intelligence Scale.

According to Vernon's structure-of-intellect paradigm, abilities can be conceptualized as a hierarchy, with a factor of general intelligence at the top of the hierarchy, and successively more specific abilities toward the bottom. This paradigm has proven useful for interpreting a number of Wechsler intelligence scales. However, most of the research with this paradigm has used exploratory factor analysis, and the validity of the paradigm for the newest Wechsler Adult Intelligence Scale (WAIS-III) has yet to be evaluated. The present study examined the WAIS-III using second-order confirmatory factor analysis, which is a more appropriate analytic tool when specific hypotheses are tested. Using the standardization sample for the WAIS-III (N = 2,450), support was found for the hierarchical factor structure with a second-order factor of general intelligence and four first-order factors of Verbal Comprehension, Perceptual Organization, Working Memory, and Processing Speed.

Adolescent↗
PubMed2000

Seattle 5-a-Day Work-Site Project: process evaluation.

The Seattle 5-a-Day Work-Site Project developed a community-based intervention to increase fruit and vegetable intake, using both environmental (including cafeteria and work-site-wide events) and individual strategies. The Employee Advisory Board developed its own protocol from a common skeleton and a minimum set of activities. Small work sites and work sites with fewer female employees delivered more displays, posters, and table tents per employee (p < .01 and p < .05, respectively). Dose was neither related to use of the intervention nor to change in fruit and vegetable intake. Use of informational materials increased fruit and vegetable intake in the cohort of employees with both baseline and follow-up data (p = .05). The intervention was associated both with increased employee use of the intervention (activities and materials) and with increased intake of fruit and vegetables. Work sites with medium average baseline intake were the most responsive. These findings can guide the development of more efficient community-based dietary interventions.

Adult↗