Legislative activity: funding reform and medical education.
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Biomedical subjects
Publications and source records attributed to R McDonald.
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OBJECTIVE: To explore the sex-specific benefits and risks of treatment of stage 1 diastolic hypertension. METHODS: Participants were African-American and white hypertensive men (n = 557) and women (n = 345) (age range, 45 to 69 years) with a diastolic blood pressure less than 100 mm Hg. Participants were randomized to treatment with placebo, chlorthalidone (15 mg/d), acebutolol hydrochloride (400 mg/d), doxazosin mesylate (2 mg/d), amlodipine besylate (5 mg/d), or enalapril maleate (5 mg/d); all were given nutritional-hygienic intervention. RESULTS: After 4 years, women who were randomized to lifestyle intervention only were less likely to be receiving step 1 therapy alone (placebo) than men who were randomized to placebo therapy (46% vs 66%, respectively, P < .01). There were significantly greater decreases in the mean systolic blood pressure in both men and women who were assigned to treatment with active drugs compared with those participants who were receiving placebo therapy; differences among treatments with active drugs were similar between men and women. Men experienced larger falls in their total and low-density lipoprotein cholesterol and triglyceride levels regardless of the treatment assignment than did women; however, there were no significant sex-by-treatment interactions. Quality-of-life indexes were generally improved with active drug treatment compared with placebo therapy in both sexes; there was a sex-by-treatment interaction for the general health index. The relative risk (RR) for combined clinical events was similar in women (RR, 0.64; 95% confidence interval [CI], (0.36 to 1.16) and in men (RR, 0.67; 95% CI, 0.40 to 1.14) who were assigned to treatment with all active drugs combined, compared with those who were receiving placebo therapy. CONCLUSION: In these exploratory analyses, men and women who were assigned to treatment with active drugs experienced greater and generally similar benefits from treatment than those participants who were assigned to lifestyle intervention only.
Collagen biosynthesis was analyzed in C57BL/6J mice homozygous for the high-growth locus. Plasma levels of insulin-like growth factor-1 (IGF-1) were significantly elevated in high-growth mice at all ages studied (3 wk-6 mo); IGF-binding proteins were also elevated. Skin biopsies were obtained from mice aged 3, 6, and 9 wk under halothane anesthesia. Mice were killed at 6 mo of age. Collagen, expressed per weight of tissue, was significantly increased in all tissues from high-growth mice, as was collagen cross-linking, expressed as moles of cross-link per mole of collagen. Expression of types I and III collagen, lysyl oxidase, and lysyl hydroxylase was increased in all tissues analyzed. There was a preferential increase in type III expression relative to type I expression. Rate and extent of accumulation of collagen in granulation tissue were measured in polyvinyl alcohol sponges implanted subcutaneously; collagen accumulation was significantly greater in the high-growth mice. These results suggest that 1) elevated circulating IGF-1 may increase collagen deposition both in normal tissue as well as in granulation tissue by increasing collagen gene expression, 2) IGF-1 may increase collagen cross-linking by stimulating expression of lysyl oxidase, and 3) the preferential increase in dihydroxylated cross-links observed in high-growth mice may be due to the stimulation of lysyl hydroxylase expression by IGF-1. In summary, elevated levels of IGF-1 appear to affect collagen both quantitatively and qualitatively, primarily through their effects on gene expression of collagen and of those enzymes responsible for posttranslational modifications of collagen.
OBJECTIVE: To determine the levels and predictors of psychological distress within a Latin American community in the Hunter region of New South Wales, Australia. METHOD: Participants (n = 184) were interviewed in their homes by a bilingual interviewer using a specially prepared questionnaire and the General Health Questionnaire (GHQ-12). RESULTS: Of the 13 independent variables examined, two demographic and two immigrant-related variables were significantly associated with an above-threshold score: marital status, employment status, perceived discrimination, and dissatisfaction with life in Australia. CONCLUSIONS: Compared to results from other community surveys, the levels of psychological distress within this Latin American community appear to be relatively high.
This study was designed to investigate the effects of aging and caloric restriction on collagen deposition in a model of wound healing. Polyvinyl alcohol sponges were implanted in Fischer 344 rats aged 6, 10, or 24 months. Sponges were removed after 7, 10, or 14 days and analyzed for hydroxyproline content and for enzymatic crosslinks. Aging was associated with a decrease in collagen accumulation as well as a delay in reaching peak rates of collagen accumulation. Levels of enzymatic crosslinks were increased in granulation tissue from old animals relative to young animals. Caloric restriction (60% of ad libitum intake) maintained only during the 2-week experimental period did not affect collagen accumulation, but did result in decreased levels of the difunctional crosslink dihydroxylysinonor-leucine (DHLNL) in sponges implanted for 10 days, but not 14 days. Caloric restriction initiated 4 months before sponges were implanted resulted in decreased collagen accumulation and decreases in DHLNL at all implantation times. These studies suggest that: (1) aging affects total collagen production as well as rate of collagen production in response to injury; (2) aging is not associated with impaired crosslinking in granulation tissue; (3) chronic caloric restriction is associated with decreased collagen production and decreased levels of DHLNL; (4) the adverse effects of chronic caloric restriction on wound healing may have a greater impact on wound healing in old animals.
The psychosocial effects of the 1989 Newcastle earthquake on 250 immigrants from non-English-speaking backgrounds (NESB) were compared with a matched sample of 250 Australian-born subjects. The NESB subjects had higher levels of both general (General Health Questionnaire-12) and event-related (Impact of Event Scale) psychological morbidity. Furthermore, NESB females had the highest levels of distress, particularly those who were older on arrival in Australia and those who experienced high levels of disruption. The results suggest that NESB immigrants, particularly women, appear to be more at risk for developing psychological distress following a natural disaster. However, level of exposure and an avoidance coping style contributed more substantially to psychological distress than ethnicity.
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A quality management program for both external beam irradiation (electron and photon modes) and brachytherapy (high dose rate (HDR) and low dose rate (LDR) has been developed. The program follows current USA federal regulations for therapeutic administration of by-product materials. After implementation of the program, 54 HDR patients, 36 LDR brachytherapy patients and 311 external beam patients (including 30 stereotactic radiosurgery cases) were treated. The results of this program are presented.
OBJECTIVE: To assess variability in the use of coronary artery bypass grafting (CABG) and percutaneous transluminal angioplasty (PTCA) in the Systolic Hypertension in the Elderly Program (SHEP) cohort with incident coronary heart disease (CHD) by age, sex, and race. DESIGN: Retrospective analysis of a multicenter prospective cohort study. SETTING: Community-based ambulatory population in academic centers. PATIENTS: Among 4736 subjects initially enrolled in SHEP, there were 432 incident cases of CHD, excluding those patients who experienced rapid or sudden cardiac death. MAIN OUTCOME MEASURE: Incident cases of CHD who underwent CABG or PTCA. RESULTS: Of those participants > or = 60 and < 75 years of age, 7.3% underwent PTCA, compared with 3.9% of those > or = 75 years (P = 0.14). 15.4% of those < 75 underwent CABG surgery, compared with 7.8% of those 75 and older (P = 0.018). When both of these endpoints, CABG and PTCA, were combined, 22.4% of those < 75 underwent a procedure, while only 11.7% of the older cohort did (P = 0.005). Twenty-six percent of men underwent either CABG or PTCA, while only 9.1% of women did (P < 0.001). Of those < 75 years of age, 31.1% of men and 12.3% of women underwent CABG or PTCA (P < 0.001). In the 75 and older age category, 19.5% of men underwent these interventions, compared with 5.9% of women (P = 0.005). Active treatment group was significantly associated with decreased use of procedures in participants < 75 year old with CHD. Race, activity limitations, number of comorbid conditions, education level, marital status, employment status, and social support were not significantly associated with CABG or PTCA use. When the variables studied were entered into a logistic regression model, increased age and female sex remained independently associated with decreased CABG and PTCA use. CONCLUSION: In the SHEP trial older patients and women, regardless of comorbid conditions, socioeconomic status, and social support, underwent less intensive cardiovascular interventions than did younger patients and men when they developed CHD.
OBJECTIVE: To compare six antihypertensive interventions for the treatment of mild hypertension. DESIGN: Randomized, double-blind, placebo-controlled clinical trial. SETTING: Four hypertension screening and treatment centers in the United States. PARTICIPANTS: Hypertensive men and women, aged 45 to 69 years, with diastolic blood pressure less than 100 mm Hg. INTERVENTION: Sustained nutritional-hygienic advice to all participants to reduce weight, dietary sodium intake, and alcohol intake, and increase physical activity. Participants were randomly allocated to take (1) placebo (n = 234); (2) chlorthalidone (n = 136); (3) acebutolol (n = 132); (4) doxazosin mesylate (n = 134); (5) amlodipine maleate (n = 131); or (6) enalapril maleate (n = 135). MAIN OUTCOME MEASURES: Blood pressure, quality of life, side effects, blood lipid levels and analysis of other serum components, echocardiographic and electrocardiographic changes, and incidence of cardiovascular events over an average of 4.4 years of follow-up. RESULTS: Blood pressure reductions were sizable in all six groups, and were significantly greater for participants assigned to drug treatment than placebo (-15.9 vs -9.1 mm Hg for systolic blood pressure and -12.3 vs -8.6 mm Hg for diastolic blood pressure; P < .0001). After 4 years, 59% of participants assigned to placebo and 72% of participants given drug treatment continued on their initial medication as monotherapy. A smaller percentage of participants assigned to the drug-treatment groups died or experienced a major nonfatal cardiovascular event than those assigned to the placebo group (5.1% vs 7.3%; P = .21). After including other clinical events, the percentage of participants affected was 11.1% for those in the drug-treatment groups and 16.2% for those in the placebo group (P = .03). Incidence rates of most resting electrocardiographic abnormalities were lower and quality of life was improved more for those assigned to drug-treatment groups rather than the placebo group. Differences among the five drug treatments did not consistently favor one group in terms of regression of left ventricular mass, blood lipid levels, and other outcome measures. CONCLUSIONS: As an initial regimen, drug treatment in combination with nutritional-hygienic intervention was more effective in preventing cardiovascular and other clinical events than was nutritional-hygienic treatment alone. Drug-treatment group differences were minimal. Pending results from large-scale clinical trials to evaluate drug treatments for their effect on cardiovascular clinical events, these findings support the recommendations of the new fifth Joint National Committee report regarding treatment choices for people with stage 1 ("mild") hypertension.
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We report on a series of 33 consecutive cases of antrochoanal polyp (ACP) treated by endoscopic sinus surgery over a five-year period. All but one patient was treated by endoscopic sinus surgery alone. This method of treatment was quite effective for ACPs. These 33 patients represent 22.3% of all nasal polyp patients on whom we operated during the same period. This incidence of ACP is greater than that generally reported in the literature. Some authors have attempted to distinguish ACPs from common nasal polyps primarily on the basis of morphology, histology, and the clinical behavior of the ACPs. In our series, a multivariate analysis, including histopathologic correlation, did not support the notion that ACPs are clearly distinct from common nasal polyps. Some interesting differences between the polyp groups did, however, become evident in our data analysis. Generally, ACPs are not thought to be associated with allergic disease; however, in our series we found the association of allergic disease with ACPs to be statistically significant (Chi-square = 4.575, p < .05).
Prior studies from our institution have shown that single photon emission computed tomography is sensitive (100%) in predicting patients at risk for serious arrhythmias. However, the positive predictive value is low (15% to 20%). The purpose of this study was to determine if quantitative analysis of single photon emission computed tomographic defects could improve predictive value. One hundred seventy-five patients with positive single photon emission computed tomographic scans were studied. One hundred two patients developed arrhythmias, 42 of which were ventricular. Arrhythmias were associated with all defect loci and all defect sizes. The incidence of arrhythmias did increase with increasing size. Patients were at risk for arrhythmias up to 72 hours after trauma. The value of single photon emission computed tomography is its ability to predict patients at risk for arrhythmias. This study shows that any single photon emission computed tomographic defect, regardless of location or size, is a significant predictor of arrhythmias.
t-Butyloxycarbonyl-alpha-aza-(4-aminophenyl)alanine phenyl ester (III: R = NH2) has been synthesized. The rate of inhibition of trypsin (EC 3.4.21.4) by this compound (due to acylation followed by slower deacylation) shows a marked pH maximum at approximately 6. The shape of the pH-rate curve is discussed in terms of (i) the normal pH-activity curve of trypsin reacting with a charged substrate, i.e. the protonated form of the amino compound, (ii) the deprotonation of the 4-amino group with pKa 4.3, and (iii) the lower rate of reaction of the enzyme with the uncharged, deprotonated form of the ester.
Dietary nutrient intakes of 91 Cambodian, 37 Laotian, and 59 Vietnamese low-income pregnant women attending a university teaching hospital outpatient clinic in Southern California were measured. The nutrient intakes of the Southeast Asian groups were compared with one another as well as with the intakes of a group of 165 low-income non-Southeast Asian pregnant women of similar height, weight, and age from the same outpatient clinic population. Computerized analysis of the 24-hour recall data showed that there were few differences in nutrient intake between the Southeast Asian groups, except that the Cambodian group consumed significantly less fat, riboflavin, vitamin D, and calcium than the Vietnamese group. However, there were a number of differences between the nutrient intakes of the Southeast Asian groups and those of the non-Southeast Asian group. These included significantly lower intakes of fat, riboflavin, folate, vitamins D and E, calcium, phosphorus, potassium, and magnesium and significantly higher intakes of thiamin, niacin, sodium, and selenium. These findings suggest that low-income Southeast Asian pregnant women have some good dietary habits that dietitians need to reinforce and other dietary habits that need improvement.
The Treatment of Mild Hypertension Study (TOMHS) is a randomized, double-blind clinical trial currently being conducted to compare the effects of nonpharmacologic therapy alone with those of 1 of 5 active drug regimens combined with nonpharmacologic therapy, for long-term management of patients with mild hypertension. Six classes of drugs were studied: (1) acebutolol (beta blocker), (2) amlodipine (calcium antagonist), (3) chlorthalidone (diuretic), (4) doxazosin (alpha 1 antagonist), (5) enalapril (angiotensin-converting enzyme inhibitor) and (6) placebo. All participants received nutritional-hygienic advice to reduce weight and sodium and alcohol intakes and to increase physical activity. End points include blood pressure change, side effects and quality-of-life indices; incidence of electrocardiographic and echocardiographic abnormalities; and incidence of cardiovascular clinical events, including death, among participants receiving drugs as first-step treatment as well as nonpharmacologic treatment compared with incidence among those participants randomized to nonpharmacologic treatment only as the initial step.
Kaposi's sarcoma is a common manifestation of AIDS, particularly in young male homosexual patients. Between 1987 and 1988, eight patients with Epidemic Kaposi's sarcoma received palliative radiation therapy. The authors' experience indicates that radiation therapy can provide good to excellent palliation for skin and oropharyngeal lesions.
This current study is concerned with the identification of the incidence of persistently low natural killer (NK) cell activity in an essentially healthy population of young adults, and the characterization of the psychological profile associated with this pattern of NK activity. Eighty-eight individuals, between the ages of 18 and 44 years, were accrued to this project. Subjects were tested serially, at baseline induction into the study, and at 2 and 4 weeks follow-up. Baseline assessment included a complete physical examination and laboratory work-up in order to exclude anyone ill at the time of enrollment, and to have complete physical status information on all subjects at the time of accrual. NK activity, urinary catecholamine levels and psychological status were also assessed at baseline, and at the specified follow-up intervals. Individuals with low NK activity were operationally defined as those having NK function either below the group mean, or below the group lowest quartile, at baseline and at two follow-up assessments. Results showed that in both univariate analyses, as well as in logistic regression models, age and the perception of environmental stressors or 'hassles' predicted persistently low NK activity. Younger subjects, who perceived environmental events to which they were exposed as more serious in nature, were more likely to exhibit a persistently low NK profile over time than older individuals who perceived daily events as less important to them.