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Biomedical subjects

D M Becker

Publications and source records attributed to D M Becker.

At least 73 records · Page 4Linked to original sources

Ending smoking at the Johns Hopkins Medical Institutions. An evaluation of smoking prevalence and indoor air pollution.

An empiric evaluation of a policy ending smoking in a large urban medical center was conducted. The study included a prospective cohort tracking of employees to measure changes in smoking behavior, environmental fires, smoking-related litter, and environmental tobacco pollution exposure. A 25% decrease in employee smoking prevalence was found (21.7% vs 16.2% before vs after policy implementation, respectively). The daily number of cigarettes reportedly smoked by employees who continued smoking and the total number smoked at work decreased across all occupational categories by an average of 25%. Significant reductions were noted in the level of public smoking and the amount of cigarette remnants. Nicotine vapor concentrations decreased significantly in all areas except restrooms. These findings suggest that visible smoking and environmental tobacco smoke exposure can be markedly decreased by instituting a policy eliminating smoking in a large medical center.

Air Pollutants, Occupational↗

Striking conservation of TFIID in Schizosaccharomyces pombe and Saccharomyces cerevisiae.

Eukaryotic promoters contain binding sites for basic transcription factors and gene-specific activator proteins. The transcription factors interact at the TATA box, which lies close to the position of transcription initiation. Activators typically bind to distant sites that can lie kilobases away from the initiation site. The factor TFIID binds specifically to the TATA box to initiate an ordered pathway of assembly of the basic transcription factors. Biochemical analyses have shown that human and Saccharomyces cerevisiae TFIID are functionally interchangeable in vitro. To study further the functional conservation of this critical factor, we are surveying proteins from divergent organisms that can substitute in vivo for the S. cerevisiae TFIID. We report here the isolation of a unique gene from Schizosaccharomyces pombe that fully complements a null mutation in SPT15, the gene that encodes TFIID in S. cerevisiae. The Schiz. pombe gene encodes a protein 93% identical (166/178) to S. cerevisiae TFIID in a region consisting of a direct repeat.

Amino Acid Sequence↗

Plasma DNA. A simple, rapid test for aiding the diagnosis of pulmonary embolism.

Previously, we reported that the sensitivity of plasma DNA for patients with pulmonary emboli was 83 to 88 percent. To confirm these findings in a more comprehensive study, we collected plasma samples from 137 consecutive patients undergoing 148 ventilation-perfusion lung scans for pulmonary embolism. DNA was measured using a counter-immunoelectrophoresis technique that used high titer precipitating double-stranded DNA antibody from a patient with systemic lupus erythematosus. In addition to 17 patients (17 lung scans) excluded for not having plasma collected, 32 patients (37 lung scans) were excluded for having either a condition other than pulmonary embolism that could be associated with plasma DNA or for having nonacute symptoms. Eighteen of 22 patients with a diagnosis of pulmonary embolism (defined by either a high probability lung scan or abnormal pulmonary angiogram) had detectable plasma DNA. Only four of 27 patients without pulmonary embolism (defined by either a normal lung scan or normal pulmonary angiogram) had plasma DNA detected. Based on these results, plasma DNA had a sensitivity of 82 percent and a specificity of 85 percent for this condition. Plasma DNA is a promising test for pulmonary embolism and could help physicians interpret equivocal lung scan findings and thereby clarify difficult decisions such as the need for pulmonary angiography.

Counterimmunoelectrophoresis↗

Elevated blood cholesterol. A risk factor for coronary heart disease.

1. The Report of the Adult Treatment Panel on the Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults is designed to provide guidance to healthcare professionals in the detection, evaluation, and treatment of adult hypercholesterolemic patients. 2. Dietary intervention, an essential part of every treatment plan, is highlighted followed by the introduction of drug treatment if the dietary intervention fails to achieve the desired results. 3. Guidelines for intervention at the worksite, including those using community resources, are discussed.

Coronary Disease↗

Factors related to functional status after coronary artery bypass surgery.

We studied physical functioning and social and leisure functioning of 125 men before, 1 month after, and 6 months after coronary artery bypass surgery. Relationships between functional status outcomes and selected psychosocial and physical variables were examined. Although functional status outcomes improved significantly 6 months after surgery, 13% of patients continued to report important functional status disabilities, and 45% reported difficulty in or no participation in moderately vigorous activities. The variable most predictive of functional status was the patient's estimation a priori of his ability to carry out specific activities (self-efficacy). Other psychosocial and physical factors, other than postoperative treadmill performance, did not add significantly to the prediction of the outcomes. Findings suggest that rehabilitative programs attempting to facilitate physical and social reintegration of the patient after coronary artery bypass surgery should test the effects of interventions to increase self-efficacy.

Activities of Daily Living↗

Strategies for increasing house staff management of cholesterol with inpatients.

This study tested the effectiveness of two conceptually different chart audit-based approaches to modifying physicians' clinical practices to conform with quality-assurance standards. The objective was to increase intern utilization of cholesterol management opportunities in the inpatient setting. Using a clinical trial study design, 29 internal medicine interns were randomly assigned to four intervention groups identified by the intervention they received: control, reminder checklists (checklists), patient-specific feedback (feedback), or both interventions (combined). Over a nine-month period, intern management of high blood cholesterol levels in internal medicine inpatients (n = 459) was monitored by postdischarge chart audit. During both a baseline and subsequent intervention period, interns documented significantly more cholesterol management for inpatients with coronary artery disease (CAD) than without CAD. During baseline, 27.3%, 24.3%, 21.7%, 12.4%, 5.4%, and 2.7% of all inpatient charts had intern documentation concerning a low-fat hospital diet, cholesterol history, screening blood cholesterol level assessment, follow-up lipid profile, nutritionist consult, and preventive cardiology consult, respectively. The feedback intervention significantly increased overall intern-documented cholesterol management among inpatients with CAD. The checklists significantly decreased overall intern-documented cholesterol management. Feedback appears to be an effective approach to increasing intern cholesterol management in inpatients.

Adult↗

Return to work after percutaneous transluminal coronary angioplasty.

A prospective study of 82 patients employed in the 6-month period before percutaneous transluminal coronary angioplasty (PTCA) was performed to determine the patterns of lag time in work resumption and the factors associated with early return to work. One month after PTCA, 59% of patients had resumed work whereas 87% were employed 6 months after PTCA. Patients who had a myocardial infarction in the month before PTCA, as well as those with less than 12 years of education, blue collar jobs and low levels of self-efficacy (self-confidence) for return to work had a lower probability of work resumption at every point in the 24 weeks of follow-up. Cox proportional hazards analysis revealed the psychosocial construct, self-efficacy, to be the strongest predictor of return to work 1 month after PTCA, independent of having a recent myocardial infarction, disease severity, age, job classification, gender and physician advice (p = 0.0006). Kaplan-Meier analysis for return to work after PTCA confirmed that patients with high self-efficacy estimates obtained just before hospital discharge after PTCA resumed employment earlier than those with low self-efficacy levels (p = 0.0001). The same relation was observed in those patients with and without a myocardial infarction in the month before PTCA, p = 0.0022 and 0.0012 respectively. These findings suggest that although PTCA is considered relatively safe and minimally invasive by physicians, patients may still lack confidence in their ability to return to work even when physically capable of doing so.

Absenteeism↗

The impact of a total ban on smoking in the Johns Hopkins Children's Center.

We report the results of a ban on smoking in The Johns Hopkins Children's Center, Baltimore, Md, beginning in July 1987. A survey 6 months before and 6 months after implementation of the ban showed current smoking prevalences to be 15% and 13.8%, respectively. The percentage of smokers who smoked at work declined from 82% before the ban to 43% after the ban. After the ban, 66% of smokers and 93% of nonsmokers agreed that a hospital should be smoke free, while 43% and 83%, respectively, agreed with this statement before the ban. Systematic observations showed a decline from 53% of visitors and staff smoking in public areas 1 month before the ban to 0% smoking 6 months after the ban. Twenty-four-hour cigarette butt counts in elevator lobbies located well within the center dropped from 940 for an average day to 19 for an average day 6 months after the ban. Finally, measurement of environmental nicotine vapor showed a decline from a weekly average concentration of 13 micrograms/m3 of nicotine 1 month prior to the ban to 0.51 micrograms/m3 of nicotine 6 months after the ban in nine lobby lounges. The results suggest that a total ban on smoking in a hospital is feasible and effective in virtually eliminating public smoking.

Adult↗

Banning smoking in a children's hospital: are employees supportive?

This study surveyed 762 professional and auxiliary employees in a large urban children's hospital to assess readiness for a total ban on smoking. The prevalence of never smokers was 63.1%, former smokers was 21.1%, and current smokers was 15.1%. Among nonsmokers, 83% indicated that a children's hospital should be smoke-free. The attitudes of former smokers were almost identical to those of never smokers. Less than half of current smokers (43%) agreed with a ban on smoking which suggests some support for a smoke-free setting even among smokers. In multivariate analysis, smokers, however, were eight times less likely to agree with such a policy, independent of age, sex, and occupation. This study suggests that the majority of employees are supportive of a total ban on smoking but that special efforts to help smokers stop smoking may enhance the effectiveness of a policy banning smoking in a children's health care facility.

Adult↗

Resistance to the Sterne strain of B. anthracis: phagocytic cell responses of resistant and susceptible mice.

Inflammatory responses were compared in vivo, and host phagocytic cell functions compared in vitro, of mice resistant (CBA/J) and susceptible (A/J) to lethal infection with the Sterne strain of Bacillus anthracis. Polymorphonuclear leukocyte (PMN) and macrophage responses at the initial site of infection were slower in A/J mice than in CBA/J mice. Whereas in A/J mice, the number of PMN ultimately responding to infection was equal to, or greater than, that in CBA/J mice, fewer macrophages accumulated. A/J mice failed to clear relatively low doses of the organisms and died. In vitro, chemotactic responses to both serum- and bacteria-derived attractants were similar for macrophages from A/J and CBA/J mice but were reduced for PMN from A/J mice. PMN and macrophages from the two mouse strains phagocytosed and killed spores in vitro to a similar extent, although killing by A/J PMN could be blocked by prior uptake of large numbers of killed spores. Thus susceptibility to lethal infection with Sterne strain correlated with the delayed influx (PMN) and reduced accumulation (macrophages) of phagocytes at the initial site of infection, but not with defective in vitro uptake or killing of spores.

Animals↗

Fusion of adenovirus E1A to the glucocorticoid receptor by high-resolution deletion cloning creates a hormonally inducible viral transactivator.

The 289-amino-acid E1A protein of adenovirus type 2 stimulates transcription from early viral and certain cellular promoters. Its mechanism is not known, and there exist no temperature-sensitive mutants of E1A that could help to elucidate the details of E1A transcriptional activation. To create for E1A such a conditional phenotype, we fused portions of E1A to the human glucocorticoid receptor (GR) to make transactivation by E1A dependent on the presence of dexamethasone. Nested subsets of the E1A coding region, centered around the 46-amino-acid transactivating domain, were substituted for the DNA-binding domain of the GR. One of the resulting chimeric proteins (GR/E1A-99), which included the entire E1A transactivating domain, stimulated expression from a viral early promoter (E3) exclusively in the presence of hormone. GR/E1A-99 did not transactivate a GR-responsive promoter. It therefore exhibited the promoter specificity of E1A while possessing the hormone inducibility of the GR. Two smaller chimeras that contained only portions of the E1A transactivating domain failed to transactivate E3. These three chimeras were constructed by a novel strategy, high-resolution deletion cloning. In this procedure, series of unidirectional deletions were made with exonuclease III on each side of the E1A coding region at a resolution of 1 to 2 nucleotides. The large number of in-frame fragments present in the collection of deleted clones facilitated the construction of the GR/E1A chimeras and can be used to create many additional fusions.

Adenovirus Early Proteins↗

Risk factors in siblings of people with premature coronary heart disease.

Prior studies of the contribution of coronary disease risk factors to familial aggregation of premature coronary disease may have underestimated risk factors by relying on self-reported risk factor prevalence levels or, when risk factors have been measured, by using cut points in excess of the 90th percentile. To determine the actual prevalence of hyperlipidemia, hypertension and diabetes, and the awareness of these coronary risk factors in unaffected family members, 150 apparently coronary disease-free siblings of 86 people who had documented coronary disease before 60 years of age were studied. All subjects participated in a 1 day screening preceded by a self-administered risk factor questionnaire and a personal interview. Participation of both the index patients and siblings exceeded 86%. With the use of nationally established recommendations for blood pressure and lipids, which are based on coronary disease risk curves, screening revealed that 48% of brothers and 41% of sisters were hypertensive, 45% of brothers and 22% of sisters had a lipid abnormality, 38% of siblings were current cigarette smokers and 4.7% were diabetic. Two or more risk factors were present in 42% of brothers and 26% of sisters. More than 75% of siblings had one or more risk factors that would require intervention. When compared with a race-, gender- and age-matched reference population from the Lipid Research Clinics Prevalence Study, distributions for blood pressure and for total and low density lipoprotein cholesterol were higher for the siblings in every gender and age group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Relationship between corticosteroid exposure and plasma lipid levels in heart transplant recipients.

PURPOSE: Accelerated coronary atherosclerosis is a major cause of heart graft failure two years and more after heart transplantation, yet its etiology remains undetermined. We conducted this study to determine the prevalence of coronary risk-associated lipid abnormalities, and the relationship between lipid levels and exposure to corticosteroids and cyclosporine, in heart transplant recipients. PATIENTS AND METHODS: The records of 92 consecutive heart transplant recipients from three different transplantation centers were reviewed. Patients from the three centers varied in age, in corticosteroid regimens, and in the proportion undergoing transplantation for ischemic cardiomyopathy. Although 11 patients were not receiving corticosteroids at the time of the study, all patients had received them immediately after transplantation. In addition to information pertaining to demographics, pretransplant medical history, rejection episodes, drug doses, renal function, and blood glucose levels, data on dietary intake and body weight were collected and plasma lipid levels were measured at the time of record review. RESULTS: A significant number, 48 (52 percent), of heart transplant recipients were above the sex- and age-adjusted 75th percentile, and 35 (38 percent) were above the 90th percentile for total cholesterol in comparison with a general reference population. Similar elevations were found in low-density lipoprotein cholesterol, triglyceride, and high-density lipoprotein cholesterol levels. Bivariate analysis demonstrated cumulative prednisone exposure (r = 0.40, p = 0.0001) and cumulative cyclosporine exposure (r = 0.22, p = 0.04) but not diet or etiology of pretransplant heart disease to be significantly associated with age- or sex-adjusted total cholesterol percentiles. Low-density lipoprotein cholesterol percentiles were also correlated with cumulative prednisone (r = 0.37, p = 0.001) and cumulative cyclosporine exposure (r = 0.24, p = 0.02). Stepwise multiple linear regression analysis, however, demonstrated cumulative prednisone exposure to be the strongest predictor of both total and low-density lipoprotein cholesterol levels and percentiles (p = 0.0001), independent of cumulative cyclosporine exposure and other clinical variables. CONCLUSION: These data suggest that long-term corticosteroid exposure may result in an increased prevalence of unfavorable lipid profiles in heart transplant recipients.

Adolescent↗

Diagnostic variability in suspected pulmonary embolism.

Over a 12-month period, we observed adult patients with suspected pulmonary embolism referred for lung scanning to determine variability in the diagnostic process. Among 269 studies, 157 lung scans were judged necessary by predetermined criteria. Ninety-three of these 157 patients had inconclusive results (low probability, intermediate probability, or indeterminate). Of these 93 patients, 42 had pulmonary angiograms, ten of which were positive. Of the 51 patients with necessary but inconclusive scans, five were poor candidates for angiography, 15 had other indications for anticoagulation, seven refused the study, and 24 had physicians who considered further studies unwarranted. Patients with and without pulmonary angiography were demographically and clinically similar. Although confirmatory testing such as pulmonary angiography was used frequently (45%) after an inconclusive lung scan, the question of pulmonary embolism was often left unanswered (55%). Methods for linking clinical judgment to lung scan results are necessary to select proper patients for invasive confirmatory testing.

Adult↗