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Biomedical subjects

M Fitch

Publications and source records attributed to M Fitch.

54 records · Page 3Linked to original sources
PubMed1981

Effects of dietary cholesterol on antibody-dependent phagocytosis and cell-mediated lysis in guinea pigs.

The effect of dietary cholesterol on antibody-dependent phagocytosis and cell-mediated cytotoxicity (ADCC) by peritoneal cells and on the susceptibility to lysis of erythrocytes was studied in the guinea pig. We found that peritoneal cells from cholesterol-fed animals (CHOL PEC) demonstrated a decreased ability to both phagocytose and lyse antibody-coated (Ab) guinea pig erythrocytes than did those from control guinea pigs (CONT PEC). This decrease was equal in groups fed cholesterol for 5 1/2-13 weeks, preanemic or anemic, and with normal or enlarged spleens. Dose response curves varying Ab concentration showed that CHOL PEC required higher concentrations of Ab to effect phagocytosis and lysis than did CONT PEC. Dietary cholesterol, while rapidly inducing morphological changes such as spurring in guinea pig erythrocytes, was found not to affect the susceptibility of the cells to lysis or phagocytosis in this assay system. These findings suggest that the increased incidence of infection in cholesterol-fed guinea pigs may be due to impaired phagocytic function and that the anemia observed in guinea pigs after 8-10 weeks of feeding cholesterol is not due to increased antibody-dependent removal of spurred erythrocytes by the phagocytic system.

Anemia↗
PubMed1979

Effects of the unsaturation of dietary fat and of arachidonate supplementation on cholesterol pool expansion in the guinea pigs.

We have studied the effects of methyl arachidonate supplementation on the lipid metabolism of guinea pigs fed cholesterol. Four groups of guinea pigs were fed a purified diet containing 9.5% hydrogenated coconut oil (HCNO), a highly saturated fat with or without the addition of 1% cholesterol, for 15 weeks. One half of the animals fed the control and the cholesterol-containing diets were supplemented with 15 mg methyl arachidonate three times per week. Supplementation with methyl arachidonate did not alter the concentration of plasma total (TC) or unesterified (FC) cholesterol, erythrocyte cholesterol and plasma phospholipid or the ratio of plasma FC/TC. Accumulation of cholesterol in the major organs of the cholesterol-fed groups was also unchanged. In both control and cholesterol-fed groups, methyl arachidonate decreased the proportion of oleic (18:1) and linoleic acids (18:2) and increased arachidonic acid (20:4) content of plasma and liver phospholipid. A comparison between the results of this study and studies using cottonseed oil showed that the type of dietary fat modifies the effects of cholesterol: plasma cholesterol levels were higher and liver cholesterol storage was lower in animals fed the saturated fat than in those fed the fat rich in polyunsaturated fatty acids (PUFA). Furthermore, in spite of similar changes in erythrocyte cholesterol content and shape abnormalities, no overt hemolytic anemia was observed in the groups fed cholesterol and saturated fat, in contrast to those fed cholesterol + PUFA-containing fat. We conclude that in guinea pigs supplementary methyl arachidonate had no hypocholesterolemic effect at the levels we fed, that circulating cholesterol levels are not a measure of cholesterol accumulation by organs and that the decrease of serum cholesterol in response of PUFA is due in part to an increase of cholesterol storage in the liver.

Animals↗
PubMedDate not supplied

A comparison of physician and patient perspectives on unconventional cancer therapies.

In two related studies about unconventional cancer therapies, patients and physicians were interviewed about their experiences and opinions. In this paper comparisons are made and implications discussed. There was general agreement among physicians and patients about the importance of providing access to information about unconventional approaches for interested patients. However, there were substantial differences in perspective on other issues, including: what constitutes 'unconventional', the helpfulness of typical physician responses to patients interested in or using unconventional therapies, the proper interface between practitioners of conventional and unconventional therapies, the reasons for communication problems (related to unconventional therapies) between physicians and patients, and the proper criteria for making decisions about unconventional therapies. Cancer specialists, family physicians and other health professionals need to look for ways to better understand and meet the needs of their patients with interests in unconventional approaches if they hope to preserve or improve relations.

Attitude of Health Personnel↗
PubMedDate not supplied

To tell or not to tell: patterns of disclosure among men with prostate cancer.

This paper draws on the results of a longitudinal, qualitative study of men with prostate cancer (treated with prostatectomy) and their spouses. Interviews were conducted separately and simultaneously with men and their spouses, at three points in time (pre-surgery, 8-10 weeks post-surgery and 11-13 months post-surgery). The primary focus in the paper is on men's responses to questions about their decisions to share information (or not) with others about their diagnosis and ongoing medical situation. Most men with prostate cancer avoided disclosure about their illness where possible, and placed great importance on sustaining a normal life. Factors related to limiting disclosure included men's low perceived need for support, fear of stigmatization, the need to minimize the threat of illness to aid coping, practical necessities in the workplace, and the desire to avoid burdening others. This study contributes to an understanding of disclosure issues related to prostate cancer, and raises issues about how best to be helpful to men, given their tendency to minimize the impact of illness, and the need for support.

Adaptation, Psychological↗
PubMedDate not supplied

Cancer self-help groups and family physicians.

PURPOSE: Despite the phenomenal growth during the past decade of cancer self-help groups for adult patients with cancer, little research has been conducted to document the interface between these groups and healthcare professionals, especially physicians. This study was initiated to provide information about family physician practices, awareness, and attitudes about self-help groups. DESCRIPTION: A survey questionnaire was mailed to a random sample of Ontario family physicians drawn from the College of Family Physicians of Canada's membership database. RESULTS: A total of 911 completed questionnaires were returned, for a response rate of 64%. A majority (56.8%) of respondents were aware of at least one cancer self-help group in their region; 26.8% of these spoke frequently with their cancer patients about such groups. Most family physicians indicated that they were positively inclined toward cancer self-help groups, giving especially high ratings of helpfulness to sharing common experiences, overcoming isolation, feeling understood, and sharing information. Ratings of potential harm were low, with the most concern expressed about the possible provision of misinformation and the promotion of unconventional therapies. Responses to an open-ended question showed that many family physicians qualify their support for cancer self-help groups, depending on patient need, group composition, and leadership. CLINICAL IMPLICATIONS: Family physicians and other members of the cancer care team should give increased attention to informing cancer patients about the potential benefits of self-help groups. Efforts need to be made to assist cancer self-help groups in developing informational brochures and to ensure that groups are listed in cancer resource directories. Educational initiatives about self-help groups would be useful for family physicians and other health professionals engaged in the care of cancer patients.

Adult↗
PubMedDate not supplied

A qualitative study of patient perspectives on colorectal cancer.

OBJECTIVES: The purpose of this study was to use qualitative methods to contribute to a complete patient perspective on the psychosocial impact of colorectal cancer. MATERIALS AND METHODS: A qualitative descriptive study was conducted in 20 patients attending a gastrointestinal follow-up clinic at the Toronto-Sunnybrook Regional Cancer Centre. The data documented included patient satisfaction and perceptions regarding to quality of care, information received, involvement in decision making, and long-term management of the illness. RESULTS: Overall, patients were satisfied with their treatment, including the quality and timeliness of the information they received, the quality of their healthcare, and the level of involvement in decision making. However, some patients were dissatisfied with information concerning long-term management of their illness. Patient care, including information and social support, was provided by cancer specialists, family physicians, family, and friends. Patients looked to cancer specialists as their primary source of information, but relied on family physicians to fill in gaps in understanding, to provide support, to manage overall care, and to act as a sounding board for ideas and treatment options. Social support was also provided by family and friends. All patients had a relatively positive outlook on their illness experience, although those with colostomies had some added difficulty. Despite the focus on positive change, many patients acknowledged difficulty coping with the side effects of treatment. CONCLUSIONS: These data indicate that patient information needs to be provided in the most common terms and the most straightforward language. Information also may need to be repeated and should include attention to long-term management of the illness. Health professionals should assume that patients may have difficulty in illness management and should encourage a discussion of patients' concerns.

Adaptation, Psychological↗
PubMedDate not supplied

Viability of granulocytes obtained by filtration leukapheresis.

Nylon filtration alters the morphology of human granulocytes and slightly reduces their phagocytic ability as measured by activation of the hexose monophosphate shunt (HMS) pathway of glucose metabolism. In addition, the ability of rat granulocytes to circulate in granulocytopenic rats is reduced, and this is not attributed to HMS activation during filtration. The activation of the hexose monophosphate shunt is related to the size of the particles rather than to the nature of the material.

Animals↗
PubMedDate not supplied

Lead and zinc removal by laboratory-scale constructed wetlands.

Constructed wetlands have the potential to trap and remove metals in mine wastewater. To determine the effectiveness of constructed wetlands for treating selected heavy metals in neutral mine effluent typical of lead mines, eight laboratory-scale constructed wetlands were set up to treat a synthetic, slightly alkaline, mine water containing 34.2 mg/L sulfate (SO4(2-)), 50 micrograms/L lead (Pb), and 300 micrograms/L zinc (Zn). After 45 days, one of the wetlands was switched to treat a synthetic smelter effluent with a much greater load of SO4(2-), sodium (Na+), and Pb. Temperature, hydraulic loading, and substrate composition typically did not affect treatment efficiency. The pH of the effluent was reduced from 8.0 to 8.5 to near neutral. The average removal in the eight wetlands was 90% for Pb and 72% for Zn. In wetlands operating on synthetic mine water, SO4(2-) was completely removed, likely by conversion to sulfide by sulfate-reducing bacteria. In the wetland operating on synthetic smelter effluent, only approximately 25% of 6 g/L influent sulfate was removed, and a breakthrough period of 4 days for Na+ was observed. Whole effluent toxicity assays on undiluted wetland effluent from wetlands treating mine and smelter water had 100% survival of fathead minnows and Daphnia magnia. Survival of Ceriodaphnia dubia was zero in undiluted effluent, but 75 to 100% survival was observed when the effluent was diluted to one-half strength.

Animals↗
PubMedDate not supplied

Developing a plan to evaluate the use of nursing conceptual frameworks.

Five hospitals in the Metropolitan Toronto area have introduced a nursing conceptual framework as the basis of practice in their agencies. A research team representing the hospitals and the University of Toronto has developed a comprehensive plan to evaluate the impact of using a nursing framework on nursing practice. This paper describes the selection of variables to be studied and the ways selected to measure them. A series of papers will follow describing the establishment of psychometric properties of the instruments and the results of the pre-test phase. Although this paper describes a process that began some time in the past, the authors have kept current the literature on the subject and the most current references are included in this paper.

Humans↗
PubMedDate not supplied

Implementation of nursing conceptual models: observations of a multi-site research team.

The general acceptance by nursing of the nursing process as the methodology of practice enabled nurses to have a common grounding for practice, research and theory development in the 1970s. It has become clear, however, that the nursing process is just that--a process. What is sorely needed is the nursing content for that process and consequently in the past 10 years nursing theorists have further developed their particular conceptual models (CM). Three major teaching hospitals in Toronto have instituted a conceptual model (CM) of nursing as a basis of nursing practice. Mount Sinai Hospital has adopted Roy's adaptation model; Sunnybrook Medical Centre, Kings's goal attainment model; and Toronto General Hospital, Orem's self-care deficit theory model. All of these hospitals are affiliated through a series of cross appointments with the Faculty of Nursing at the University of Toronto. Two community hospitals, Mississauga and Scarborough General, have also adopted Orem's model and are related to the University through educational, community and interest groups. A group of researchers from these hospitals and the University of Toronto have proposed a collaborative project to determine what impact using a conceptual model will make on nursing practice. Discussions among the participants of this research group indicate that there are observations associated with instituting conceptual models that can be identified early in the process of implementation. These observations may be of assistance to others contemplating the implementation of conceptually based practice in their institution.

Attitude of Health Personnel↗
PubMedDate not supplied

The meaning of illness questionnaire: reliability and validity.

The reliability and validity of a recently developed Meaning of Illness Questionnaire (MIQ) is described. Questionnaire content was based on the work of Lazarus and Folkman (1984b). Three hundred twenty chronically ill subjects completed the 33-item MIQ and two open-ended questions. Subjects also completed the 45-item Psychosocial Adjustment to Illness--Self-Report Scale (PAIS-SR) described by Derogatis and Lopez (1983). Test-retest reliability for 70 subjects was, on the whole, substantial (kappa = .45 to 1.00) as was the ability of nurse clinicians to reliably categorize the qualitative component of the questionnaire into one of 12 categories (kappa = .64). The factor structure of the questionnaire supported the theoretical assumptions underlying the instrument. Three of the factors of meaning given the illness, R2 = .46, and/or three items, R2 = .60, had more power than coping behavior in explaining a person's adjustment to chronic illness. The questionnaire has accumulated reliability and validity in measuring a variety of concurrent yet divergent meanings that may be given an illness for three chronically ill populations--those with mixed cancer, rheumatological, and gastroenterological disorders.

Adaptation, Psychological↗