Ultrastructural localization of peroxidase activity in normal human bone marrow cells.
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Biomedical subjects
Publications and source records attributed to M A Clark.
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BACKGROUND: Patients' perceptions of their physician's role in smoking cessation, using the 4As protocol (asking, advising, assisting, and arranging), were assessed with a focus on associations with age (18-29, 30-49, and > or = 50) and stage of readiness to stop smoking (precontemplation, contemplation, and preparation). METHODS: Self-administered questionnaires were completed by 524 smokers presenting for regularly scheduled appointments at six clinics of an HMO in the Chicago metropolitan area. RESULTS: Almost all patients said their physician should ask about their smoking status and advise them to quit. About half said their physician should assist them with quitting, and about two-thirds said their physician should follow up (arrange) on their smoking behavior. Bivariate associations were found for endorsement of the 4As with both age and stage. Multiple logistic regressions found age was the most consistent and strongest correlate of 4As endorsement, with younger smokers more likely than those age 50 or older to endorse the 4As protocol. CONCLUSIONS: A proactive health promotion orientation should be encouraged among physicians. Patients should be screened for stage of readiness to stop smoking so that health-care providers can emphasize aspects of the 4As protocol that are most appropriate for each patient. Age-tailored smoking cessation strategies should be employed within stages of readiness to stop smoking.
BACKGROUND: The ability to study health-related behaviors in combination rather than singly will lead to a more comprehensive approach to health promotion. This investigation focused on mammography and Pap testing. One index was created to reflect the recency of receiving both examinations. A second index integrated opinions about the two procedures into a single measure, guided by the pros, cons, and decisional balance constructs of the Transtheoretical Model of behavior change. METHOD: Data were drawn from the baseline and 1-year follow-up surveys of an HMO sample of women ages 40-74 (N = 1,605). Data collection occurred by telephone. A series of analyses examined whether recency of screening was associated with opinions about screening. RESULTS: The first analysis showed that recency of Pap testing and whether or not a Pap test was obtained between the two surveys were associated with opinions about Pap testing. The next analysis examined the association between the indicator for regularity of both Pap testing and mammography, with the measure of opinions toward the two procedures. The variable measuring receipt of Pap test and mammography was associated with the combined measure of opinions. CONCLUSIONS: The ability to employ combined indicators for recency of testing and test-related opinions is promising for being able to take a more comprehensive approach to women's health. The paper discusses methodological considerations that arise when attempting to integrate two or more behaviors.
BACKGROUND: Tailoring is a promising technique for encouraging greater performance of health-related behaviors. Tailored interventions are designed to be more individualized to personal characteristics, in contrast to "standard" interventions where all participants receive the same materials. METHODS: A total of N = 1864 women aged 40-74 were recruited from a staff model HMO and randomly assigned to one of three intervention groups: (a) No Educational Materials, (b) Standard Materials, and (c) Stage-Matched Materials. A provider-directed component was common across all three conditions. The Standard and Stage-Matched groups each received two mailed educational packets after baseline and follow-up telephone interviews. The Stage-Matched intervention was based on the Transtheoretical Model of behavior change. RESULTS: Analyses of n = 1397 women (after all attrition) showed that receipt of mammography after the baseline interview was higher for the Stage-Matched group (63.6%) than for the No Materials group (54.9%; OR = 1.43, 95% CI = 1.10, 1.86). The Standard intervention group was intermediate (58. 5%). The Standard group did not differ from the No Materials group, but did differ from the Stage-Matched group in multivariate analysis. CONCLUSIONS: Stage-matched, tailored materials may be a means to encourage screening mammography. Such interventions can be implemented by telephone and mail.
This review aims to summarize current data describing the characteristics of bovine coronavirus (BCV) and the three clinical syndromes with which this virus is associated. The first half of this paper consists of a general description of the virus, commencing with a brief outline of the methods used for in vitro growth. The structure of the virus is then described in more detail, with particular reference to the structure and functions of the four major viral proteins. This is followed by an outline of the unique replication strategy adopted by coronaviruses. The second half of this review discusses the clinical significance of the virus, beginning with a detailed account of BCV-induced neonatal calf diarrhoea, the clinical syndrome with which this virus is most commonly associated. The clinical and epidemiological importance of BCV respiratory tract infection is then discussed, and finally the evidence supporting the aetiological role of BCV in outbreaks of winter dysentery in adult cattle is examined.
To develop effective age-appropriate strategies for smoking cessation, it is important to understand factors associated with readiness to quit smoking. This article presents results from an analysis of the role of symptomatology in the decisions to quit smoking among three age groups (18-34, 35-54, and > or = 55 years) from a larger sample of smokers in a managed-care setting. Two measures of readiness to quit smoking were used: stages of change and intention to stop. Using ordinal logistic regression, we found that smokers in the middle and oldest age groups who had experienced at least three of five symptoms in the previous 2 weeks were more likely to be in higher stages of readiness. Regardless of age, smokers who attributed symptoms to smoking were more motivated to try to quit, whereas those who attributed symptoms to aging were less likely to intend to stop smoking. Findings from this study indicate a symptom-based approach to smoking cessation may be a useful strategy, especially in provider-based interventions.
Intestinal M cells, the specialised antigen-sampling cells of the mucosal immune system, are exploited by Salmonella and other pathogens as a route of invasion. Salmonella entry into M cells and colonisation of Peyer's patches involve mechanisms critical for infection of cultured cells as well as factors not accurately modelled in vitro.
Tumour necrosis factor alpha (ref. 1), synthesized primarily by monocytes in response to various invasive agents, induces a wide variety of biological effects relevant to regulating cell growth and differentiation, including the selective killing of some tumour cells and the growth stimulation of some normal fibroblasts. As tumour necrosis factor (TNF) appears to kill tumour cells preferentially, we asked whether TNF sensitivity correlates with the expression of specific oncogene(s). If so, by examining the cellular target(s) of the oncogene product, it might be possible to identify specific factor(s) which mediate TNF action. By using an in vitro cytotoxicity assay with NIH 3T3 and Fisher BRK-derived cells expressing exogenously introduced oncogenes, we found that adenovirus E1A proteins induce susceptibility to TNF killing.
This article is based on a program that was developed by the Center for Healthy Communities (CHC), a community-academic partnership in Dayton, Ohio, that continues to act as a force for change in health professions' education and health delivery, stressing the philosophy of "doing with" instead of "doing for" or "doing to." The Health Action Fund is a grassroots health communications and social marketing program that targets community groups who are involved often in health promotion activities developed by large agencies. However, rather than taking the traditional approach to health promotion and prevention where program development and implementation is left to professionals, a different approach was taken that encourages members of neighborhoods, a community group, or a church to identify a problem and then develop a way to address that problem for their group. The program focuses on neighbors helping neighbors where communities take the lead in health promotion and prevention activities. We discuss in detail the project's innovation, challenges and how they have been addressed, qualitative and quantitative improvements made to the program, and how the program serves as a model for other communities.
A type of slow-recovery from high temperature CO2 exposure is a wild-type characteristic of Drosophila simulans. Species hybrids of wild-type D. melanogaster and D. simulans have intermediate recovery times. The response to nitrogen exposure at both high and low temperatures is the same for the two species suggesting that the observed CO2 response is more than just anoxia. Since there is no female bias in hybrids, and since injections of D. simulans extract into D. melanogaster produced no increase in CO2 sensitivity in the recipients, we conclude that the prolonged recovery time results from genomic differences between D. simulans and D. melanogaster, and is not due to a sigma-like infectious agent.
As observers of human behavior, infants are faced with a complex flow of motion in which pauses are rare and only occasionally coincide with boundaries between intentional actions. Two studies investigated whether, despite such complexity, 10- to 11-month-old infants (N = 16 for each study) possess skills for parsing ongoing behavior along boundaries correlated with the initiation and completion of intentions. After being familiarized with digitized sequences of continuous everyday action, infants showed renewed interest in test versions in which motion paused in the midst of an actor's pursuit of intentions (interrupting test videos). In contrast, pauses that suspended motion at intention boundary points (completing test videos) sparked no such renewed interest on infants' part. Moreover, basic salience differences between the two types of test videos were not the source of infants' increased interest when intentions were interrupted (Study 2). These findings demonstrate that infants readily detect disruptions of the structure inherent in intentional action, and hence parse ongoing behavior with respect to such structure. Such parsing skill is likely a prerequisite to the development of genuine intentional understanding.
BACKGROUND: Study of involuntary skeletal muscle function (MFA) has been well accepted in the area of nutrition assessment and potentially offers a means for following progress of the critically ill patient. We report on the application of this technique to intensive care patients. METHODS: MFA was performed by study of the contraction/relaxation characteristics of the adductor pollicis muscle of the thumb after ulnar nerve stimulation. Serial measurements were made in 16 critically injured patients and 28 patients with severe sepsis and were compared with those obtained from 26 control subjects. Extent of loss of total body protein (TBP) was quantified with in vivo neutron activation. RESULTS: Significant difficulties exist in applying this technique to intensive care patients. In the critically injured, only five acceptable traces could be obtained from a possible 58 measurements. For patients with severe sepsis it was possible to obtain an acceptable trace on 12 of 56 occasions. Neuromuscular blockade and lack of patient cooperation were significant impediments to MFA study. Although frequently perceived as unpleasant by these patients, there was no long-term morbidity associated with MFA. No significant differences were seen in maximal relaxation rate at 30 Hz (MMR30) or force frequency ratios (F10/50 and F30/ 50) between trauma patients and controls. In the sepsis patient group, a significantly higher F10/50 was measured (52% +/- 3% severe sepsis vs 40% +/- 1% control subjects, p < .01). Six patients had MFA measured approximately 21 days after the illness, by which stage they had lost 11% of their initial TBP. Compared with control subjects, no significant differences were observed in MRR30 or F30/50, whereas a higher value for F10/50 was measured (48% +/- 1% critical illness vs 40% +/- 1% control subjects, p < .01). CONCLUSIONS: The MFA technique is difficult to apply to intensive care patients. No significant disturbance to MFA is seen after critical injury. Severe sepsis results in an elevation of F10/ 50 only. When able to be obtained, MFA results do not reflect the extent of proteolysis but are indicative of the state of cellular energetics.
BACKGROUND: Our group wanted to test the hypothesis that plasma levels of insulin-like growth factor 1 (IGF-1), transferrin, and prealbumin are useful markers of nutritional progress in severe sepsis and multiple injury. METHODS: Measurements of IGF-1 and plasma proteins were made in critically ill patients as soon as they were hemodynamically stable and 5, 10, 15, and 21 days later. The magnitude and direction of the measured changes were compared with the magnitude and direction of the change in total body protein in the same time period. RESULTS: Fourteen patients with severe sepsis and 10 multiply injured patients were studied. As a group they had an increased metabolic expenditure that peaked at 153% of normal and lost approximately 12.0% of total body protein. An early fall in IGF-1 and plasma proteins accompanied a marked acute phase response, and recovery occurred while hypermetabolism and net proteolysis continued. No correlation existed between changes in IGF-1 or plasma proteins and the change in total body protein. CONCLUSIONS: Plasma levels of IGF-1, transferrin, and prealbumin are not useful for following changes in protein stores early in the course of critical illness.
Using analogs of known vascular ATP-sensitive K+ channel (KATP) blockers, we identified compounds with a wide range of potencies (over 500-fold) in their capacity to block the hypotensive response of 0.2 mg/kg pinacidil in rats. The most potent of these, U-97025E, belongs to a newly disclosed class of compounds, the cyanoguanidines. U-97025E at 0.04 mg/kg blocked 50% of the depressor response induced by 0.2 mg/kg pinacidil. The maximal natriuresis induced by U-97025E (0.4 mg/kg i.v.) increased Na+ excretion by approximately 60%. This natriuresis is of the same magnitude as that induced by thiazide without any effect on K+ excretion. We found a high degree of correlation between natriuretic potency and the capacity to block the blood pressure lowering effects of pinacidil, both among closely related analogs and dissimilar compounds. These findings imply an obligatory rather than incidental relationship between vascular KATP blockade and natriuresis. The exact molecular link of the vascular and renal effects remains to be determined.