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Biomedical subjects

M G Morgan

Publications and source records attributed to M G Morgan.

At least 37 records · Page 2Linked to original sources
PubMed1994

Evaluating risk communications: completing and correcting mental models of hazardous processes, Part II.

We propose a decision-analytic framework, called the mental models approach, for evaluating the impact of risk communications. It employs multiple evaluation methods, including think-aloud protocol analysis, problem solving, and a true-false test that allows respondents to express uncertainty about their answers. The approach is illustrated in empirical comparisons of three brochures about indoor radon.

Air Pollution, Indoor↗
PubMed1994

Perception of risks from electromagnetic fields: a psychometric evaluation of a risk-communication approach.

Potential health risks from exposure to power-frequency electromagnetic fields (EMF) have become an issue of significant public concern. This study evaluates a brochure designed to communicate EMF health risks from a scientific perspective. The study utilized a pretest-posttest design in which respondents judged various sources of EMF (and other) health and safety risks, both before reading the brochure and after. Respondents assessed risks on dimensions similar to those utilized in previous studies of risk perception. In addition, detailed ratings were made that probed respondents' beliefs about the possible causal effects of EMF exposure. The findings suggest that naive beliefs about the potential of EMF exposure to cause harm were highly influenced by specific content elements of the brochure. The implications for using risk-communication approaches based on communicating scientific uncertainty are discussed.

Attitude to Health↗
PubMed1993

Controversies in the laboratory diagnosis of community-acquired urinary tract infection.

Urine samples constitute the largest single category of specimens examined in most medical microbiology laboratories. The everyday nature and apparent simplicity of urinary tract infection belies the intense debate and controversy regarding the optimal methods of collection, transport and processing of urine specimens and reporting of results. There is considerable variation in the interpretation of quantitative culture results between laboratories and the etiology of abacterial cystitis remains unclear. Microscopy to detect pyuria provides information on an important indicator of inflammation and it has been proposed that detection of urinary antibody may provide similar information. Neither of these indices of host response is suitable for use in a screening test for urinary infection however, although they may usefully contribute to the interpretation of significance of culture results. The development of screening tests and automated systems continues, but at present microscopy and culture remain the most important techniques for laboratory diagnosis. However, these techniques have so far failed to provide an etiological diagnosis for abacterial cystitis and this remains a major area for research.

Adult↗
PubMed1993

Factors associated with severity of depression and high-risk sexual behavior among persons diagnosed with human immunodeficiency virus (HIV) infection.

Whereas some people appear to cope after learning that they have human immunodeficiency virus (HIV) infection, others experience depression and suicidal ideation. In this study, 142 persons with HIV infection were administered the Center for Epidemiological Studies Depression Scale (CES-D). High levels of depression were predicted by lower perceived social support, attributions that health was influenced more by chance, high-risk sexual behavior practices, and greater number of HIV illness symptoms and greater duration of time knowing of one's own positive serostatus. Ongoing high-risk sexual behavior practices were predicted by higher levels of recreational drug use and of depression. These findings highlight the need for improved mental health services for persons with HIV conditions.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Outbreak of Moraxella catarrhalis in a respiratory unit.

The clinical and epidemiological features of an outbreak of nosocomial Moraxella catarrhalis infection in a respiratory unit are described. Six isolates from five patients were shown to be indistinguishable by immunoblotting and restriction endonuclease analysis and different from 11 other, unrelated clinical strains.

Cross Infection↗
PubMed1993

Outcome of cognitive-behavioral and support group brief therapies for depressed, HIV-infected persons.

OBJECTIVE: Although many studies have documented patterns of emotional distress in persons with HIV disease, there have been few controlled evaluations of therapy outcomes with these individuals. This research evaluated the effects of brief cognitive-behavioral or social support group therapy with this population. METHOD: Sixty-eight depressed men with HIV infection were randomly assigned to one of three conditions: eight-session cognitive-behavioral groups, eight-session social support groups, or a comparison condition. Before and after intervention and at 3-month follow-up, all participants were individually assessed by using measures of symptoms of distress as well as substance use and sexual practices. RESULTS: Relative to the comparison group, both the cognitive-behavioral and social support group therapies produced reductions in depression, hostility, and somatization. The social support intervention also produced reductions in overall psychiatric symptoms and tended to reduce maladaptive interpersonal sensitivity, anxiety, and frequency of unprotected receptive anal intercourse, while the cognitive-behavioral intervention resulted in less frequent illicit drug use during the follow-up period. Tests for clinical significance of change particularly underscored benefits of the social support group intervention both at postintervention and at long-term follow-up. CONCLUSIONS: Brief group therapy for depressed persons with HIV infection produced reductions in symptoms of distress. The two forms of therapy resulted in shared and unique improvements in functioning, although social support groups focused on emotional coping presented greater evidence of clinically significant change. As more persons contract HIV infection and live longer with HIV disease, further research is needed to evaluate outcomes of mental health services with these individuals.

Adult↗
PubMed1992

Alternative functional relationships between ELF field exposure and possible health effects: report on an expert workshop.

If exposure to 60 Hz fields poses risks to public health, the relationship between exposure and risk may involve something other than the product of field strength and time. Such alternative possible relations, or "effects functions," are of great interest to epidemiologists, engineers, risk analysts, and regulators. A structured survey and workshop were used to explore whether leading researchers in bioelectromagnetics share similar views about alternative possible effects functions. Substantial agreement was found about several effects functions in a few specific contexts such as calcium-ion efflux and cell signalling, and biosynthesis pathways. No significant agreement emerged in many other contexts. No effects function possibilities were ruled out. Further effort of this sort was judged unlikely to yield greater consensus until more complete scientific understanding becomes available. However, a series of structured workshops on research planning and priority setting were judged to hold great potential for useful results.

Animals↗
PubMed1992

Use of molecular methods to characterize Moraxella catarrhalis strains in a suspected outbreak of nosocomial infection.

Sodium dodecyl sulphate-polyacrylamide gel electrophoresis of whole cell protein, immunoblotting with normal human serum and restriction endonuclease analysis using Taq I enzyme were applied to 38 clinically significant isolates of Moraxella (Branhamella) catarrhalis obtained during a suspected outbreak of nosocomial infection. Each of 18 strains had individual profiles by at least two of the three methods (unique strains). The remaining 20 strains were assigned to five groups (A-E) on the basis of similarity by at least two of the three methods. Isolates within groups A, D and E were homologous by all three methods. Immunoblot groups B and C had two distinct whole cell protein profiles (B1 and B2) but indistinguishable restriction endonuclease profiles (group B/C). This emphasizes the need to use more than one technique in characterizing strains from suspected outbreaks of nosocomial infection. Grouped strains were more likely to originate from the same hospital ward than unique strains and were associated with a significantly longer median time from patient admission to strain isolation (14 versus 3.5 days, p less than 0.005). Furthermore, the beta-lactamase activity was homologous within the groups. The results suggest that nosocomial infection involving several distinct Moraxella catarrhalis strains persisted over a period of months, involving at least 20 patients on three different wards. Such infection is probably common in wards harbouring suitably predisposed patients. The mode of transmission remains to be elucidated, but the above three techniques possess sufficient reproducibility and discriminatory ability to constitute suitable investigative tools.

Aged↗
PubMed1992

Citrobacter diversus brain abscess: case reports and molecular epidemiology.

Citrobacter diversus brain abscess occurred in two infants in Aberdeen, 5 months apart. These are the first reported cases of this condition in the UK since 1976. Restriction endonuclease analysis with SacI enzyme showed blood and CSF isolates from both patients to be identical and different from 10 other clinical isolates of C. diversus and one C. amalonaticus strain. Furthermore, isolates of C. diversus from patients belonged to biotype "d" whereas control isolates were of biotypes "a" or "e". Because both infants attended the same central and peripheral maternity units, this raised suspicions of long term contamination of the hospital environment by this organism. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) patterns of whole-cell proteins and immunoblotting with normal human serum were remarkably homogeneous for all 13 C. diversus strains and thus were not useful for typing. However, the only C. amalonaticus strain was clearly differentiated from C. diversus strains by SDS-PAGE. Management of the infants included multiple intravenous antibiotic therapy for 4-6 weeks and repeated computerised tomography (CT) scanning and drainage of the abscess cavity. Both children survived albeit with some minor degree of brain damage.

Anti-Bacterial Agents↗
PubMed1992

Characterisation of hospital isolates of Moraxella (Branhamella) catarrhalis by SDS-PAGE of whole-cell proteins, immunoblotting and restriction-endonuclease analysis.

Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of whole-cell proteins (WCP), immunoblot analysis and DNA restriction-endonuclease analysis (REA) were applied as potential typing methods to 31 clinically significant strains of Moraxella (Branhamella) catarrhalis, five of which came from a suspected outbreak of nosocomial infection in a respiratory-diseases ward. Twelve of 31 isolates were placed in four groups, each of which contained strains indistinguishable by the three typing techniques used. Each of a further two groups contained two strains, and they were similar by at least one technique; the remaining 15 strains were unique by all three methods. Four of five strains from the suspected outbreak were indistinguishable by SDS-PAGE of WCP, immunoblotting and REA. Results show that SDS-PAGE of WCP, immunoblotting and REA are suitable techniques for characterising M. catarrhalis and that there is a considerable degree of strain heterogeneity. Nosocomial infection with M. catarrhalis may be relatively common and further epidemiological studies with a combination of typing techniques are indicated.

Aged↗
PubMed1992

AIDS/HIV risk behavior among the chronic mentally ill.

OBJECTIVE: There is growing concern that chronic mentally ill adults living in the community have a high risk for HIV infection. The purpose of this study was to identify risk knowledge, high-risk behaviors, and risk-related encounters of chronic psychiatric outpatients. METHOD: Detailed information on high-risk behaviors and risk-related situations during the past 12 months was collected from 60 outpatients appearing for regular visits at inner-city community mental health clinics. RESULTS: Of the 60 outpatients, 37 (62%) had been sexually active during the past year, and 42% of the men and 19% of the women reported multiple sexual contacts and infrequent use of condoms during intercourse. Assessments of the patients' knowledge of AIDS risks revealed substantial deficits in their practical understanding of AIDS and risk reduction measures. Although use of intravenous drugs was uncommon in this group, many subjects reported histories of 1) trading sex for money, drugs, or a place to stay, 2) coercion to engage in unwanted sex, 3) causal sexual encounters, and 4) sexual activity after use of drugs or intoxicants. Twenty percent of the subjects had met their sexual partners on the streets, in parks, or in other public places. One-third had been treated for sexually transmitted diseases other than AIDS. CONCLUSIONS: These findings underscore the need for AIDS risk assessment, counseling, and prevention programs for the chronic mentally ill.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Pregnancy and childbirth beliefs and practices of American Hare Krishna devotees within transcultural nursing.

The followers of Krishna Consciousness are primarily young men and women of child-bearing age who desire healthy pregnancies within the beliefs and practices of their particular culture. The researcher spent a year and a half with American Hare Krishna devotees in a large Southeastern city and on a farm in a neighboring state. The researcher used Leininger's Cultural Care Theory and the ethnographic qualitative research method to focus on the ethnohistory, social structures, and care and caring beliefs and practices of the group related to pregnancy and childbirth. Transcultural nursing implications were derived from the study. While the research was done in 1981 and 1982, the researcher has been back to visit the Krishna devotees several times. Contact with other Krishna followers in different places has also been accomplished since the study. The researcher has found that the same cultural beliefs, practices, and values have prevailed within the group over the years.

Attitude to Health↗
PubMed1992

Community AIDS/HIV risk reduction: the effects of endorsements by popular people in three cities.

OBJECTIVES: It is critical to extend community-level acquired immunodeficiency syndrome (AIDS) prevention efforts beyond education alone and to develop models that better encourage behavioral changes. Gay men in small cities are vulnerable to human immunodeficiency virus (HIV) infection due to continued high rates of risk behavior. This research introduced an intervention that trained popular people to serve as behavioral change endorsers to peers sequentially across three different cities. METHODS: Populationwide surveys were conducted of all men patronizing gay clubs in each city to establish risk behavior base rates. After a small cadre of popular "trendsetters" were identified, they received training in approaches for peer education and then contracted to communicate risk reduction recommendations and endorsements to friends. Surveys were repeated at regular intervals in all cities, with the same intervention introduced in lagged fashion across each community. RESULTS: Intervention consistently produced systematic reductions in the population's high-risk behavior (unprotected anal intercourse) of 15% to 29% from baseline levels, with the same pattern of effects sequentially replicated in all three cities. CONCLUSIONS: This constitutes the first controlled, multiple-city test of an HIV prevention model targeting communities. The results support the utility of norm-changing approaches to reduce HIV risk behavior.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Left ventricular aneurysmectomy in patients with poor left ventricular function.

Physical performance and left ventricular (LV) function in the resting state were assessed in 22 patients with postinfarction anterior-apical left ventricular aneurysm (LVA) and global ejection fraction less than or equal to 20% who subsequently underwent radical LVA resection. The basic findings in the 20 survivors of surgery were significant improvement of global systolic LV function and more or less complete recovery of regional ejection fraction in the predominantly viable low and high lateral LV wall. This improvement was evident in patients with concomitant bypass grafting as well as in those with isolated and ungraftable lesions of the left anterior descending (LAD) coronary artery. We conclude that postinfarction anterior-apical LVA in a poorly functioning LV is suitable for surgical treatment, which can be accomplished with acceptable risk. All graftable stenotic major coronary arteries should be bypassed, in addition to the LVA resection, but a minority of patients with isolated, ungraftable LAD disease are likely to benefit from aneurysmectomy alone.

Adult↗