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J D Knox

Publications and source records attributed to J D Knox.

At least 19 recordsLinked to original sources
PubMed1991

Effects of hyperthermia on microtubule organization and cytolytic activity of murine cytotoxic T lymphocytes.

When murine cytotoxic T lymphocytes (CTL) are heated at 42 degrees C for 30 min their ability to lyse their target cells (TC) is severely impaired. When the CTL are allowed to recover at 37 degrees C, a partial recovery of cytolytic activity that peaks within 6 h is observed. A dye exclusion assay demonstrated that such a heat shock does not affect the viability of the CTL and direct microscopic observations established that their ability to bind to TC is not impaired. Therefore, the step or steps inhibited by hyperthermia are subsequent to TC recognition and binding. Kupfer et al. ((1983) Proc. Natl. Acad. Sci. USA 80, 7224-7228) demonstrated that upon binding to an appropriate TC, a rapid orientation of the Golgi apparatus and the microtubule organizing center (MTOC) occurred within the CTL so that the two organelles face the TC. This orientation is a prerequisite for efficient TC lysis. We have shown by immunofluorescence and confocal microscopy, using a monoclonal antibody to tubulin and a rabbit autoimmune serum that binds a centriole-associated protein, that the organization of the MTOC-microtubule array is disrupted by hyperthermia. EM suggests that this disorganization of the microtubules may result from an aggregation of the pericentriolar material. The recovery of cytolytic activity is coincident with the reorganization of the microtubules about the MTOC. These findings suggest that the initial inhibitory effect of hyperthermia on CTL function results from the disruption of microtubule organization.

Animals↗
PubMed1989

Biologic variation of common hematologic laboratory quantities in the elderly.

Analytic, within-subject, and between-subject biologic variations were estimated for leukocytes, erythrocytes, hemoglobin, hematocrit, mean cell volume (MCV), mean cell hemoglobin (MCH), mean cell hemoglobin content (MCHC), platelets, and a three-component differential count (lymphocytes, monocytes, and granulocytes in terms of both concentration and percentage of leukocytes) in cohorts of 12 male and 12 female healthy elderly subjects. The assays were performed with an Ortho ELT-800 automated analyzer. The estimates of within-subject biologic variation were similar to published data on young subjects, indicating that this aspect of homeostasis is not compromised in the elderly. The data were used to derive objective analytic goals; goals were surpassed except for assays of erythrocytes, hematocrit, and the derived MCV, MCH, and MCHC. The changes required for serial results to be significantly different were determined and found to be generally valid because most quantities have no heterogeneity of within-subject variation. All quantities had significant individuality; in consequence, conventional population-based reference values are of limited utility, and screening using reference limits will not detect latent or early disease in many subjects.

Aged↗
PubMed1989

Breaking bad news: medical undergraduate communication skills teaching and learning.

Teaching on the theme of 'breaking bad news' was selected for special development as part of an introductory course on communication skills for preclinical medial students in 1987. Eight parents of handicapped children and three patients terminally ill with neoplastic diseases cooperated in a series of semi-structured group discussions in which students were encouraged to interact with patients and children. The patients/parents readily assumed the role of teachers and where it was possible, they participated in similar sessions the following year. Analysis of questionnaires indicated that the plan had proved acceptable to patients, relatives and students. Follow-up of student opinion one year later indicated that students felt they had derived benefit from these opportunities to learn first-hand from patients and parents of handicapped children.

Adult↗
PubMed1989

What is ... a modified essay question?

Medical education is moving to a more problem-orientated basis than was the case formerly. The Modified Essay Question has its origins in this movement, being introduced in the late 1960s as one assessment technique more suited to general practice than other traditional assessment methods. In its original form it is a paper exercise based on an evolving situation presented by a patient in primary care. Experience with the technique in different countries is briefly summarised, and its applications to assessment and to teaching are discussed. Despite shortcomings this method appears to be standing up to the test of time.

Education, Medical↗
PubMed1989

Biological variability of 26 clinical chemistry analytes in elderly people.

Analytical, within-subject, and between-subject components of variation were estimated for 26 clinical chemistry analytes from duplicate analyses of 10 specimens collected from 27 healthy elderly subjects over a period of 20 weeks. Within-subject variations were similar to those generated previously by us in younger subjects. We conclude, therefore, that homeostasis is not compromised by age alone, and biological variability does not increase simply with age. All analytes except serum water had marked individuality, showing that conventional population-based reference values are of limited utility. The critical differences required for two results to be significantly (P less than or equal to 0.05) changed are not the same as those that prompt action by clinicians. Although heterogeneity of within-subject variation does exist, we believe that the critical differences generated will be useful in routine clinical decision making.

Adult↗
PubMed1988

Diagnosis of occupational dermatitis by general practitioners and employment medical advisors: a pilot study.

This pilot study examined how closely general practitioners and employment medical advisors agreed when jointly investigating occupational dermatitis. The criterion for admitting a patient to the study was dermatitis on one or both hands. This presented most commonly among men aged 41-60 years and women aged 21-40 years. There was some reluctance among general practitioners to take part in the study, probably owing to the medico-legal problems associated with this condition. General practitioners and employment medical advisors were equally likely to attribute a case of dermatitis to occupational factors if the patient was employed in industry; but if the patient was in nonindustrial employment, general practitioners were more likely to consider the possibility of an occupational origin than employment medical advisors. These differences suggest that before initiating a wider study more information is required concerning the trigger mechanisms for dermatitis on the hands in order to reduce the diagnostic variability.

Adult↗
PubMed1987

Rheumatic diseases: a general practitioner's view.

Patients with rheumatic complaints are the subject of some 10% of the general practitioner's work. Approximately half of this work is related to the hitherto relatively neglected group of varied soft-tissue conditions, most of which are self-limiting and of a minor nature. Against a background of such diagnostic 'noise', the general practitioner has to remain alert for the fainter 'signal' of serious disease--rheumatic and non-rheumatic--at an early stage. Continuity of care calls on special qualities, behaviours and abilities in the doctor to boost and maintain morale, to coordinate management and to participate in team care. In addition to more traditional therapeutic measures, including analgesics, NSAIDs, disease-modifying drugs and physiotherapy, joint replacement is seen as a significant contribution. There is room for improvement in the structure process and outcomes of delivery of care as it may relate to rheumatic diseases. A simple illustration, based on a general practice audit of gout, is suggested as a possible model by which quality of care could be enhanced at the level of individual patients. While there is not a great deal of scope afforded to the general practitioner in the exercise of primary prevention of the rheumatic diseases, early diagnosis and timely support for carers of patients suffering from chronic rheumatic diseases are areas worth attention. Promotion of self-help is seen as a worthwhile activity in humanitarian and economic terms, though it calls for an appropriate balance to be struck.

Chronic Disease↗
PubMed1985

Comparison of response rates to a postal questionnaire from a general practice and a research unit.

A postal questionnaire study was carried out in an urban general practice to determine the effect of the introductory letter being sent by the participants' own general practitioner compared with that from a letter sent directly from a research unit. By sequential sampling 409 individuals aged between 40 and 59 were assigned to one of two groups. The people in one group were written to by their own general practitioner and those in the other by a doctor from a research unit. Husbands and wives were paired and were always sent the same letter. A second letter was sent to nonresponders after one month. The response rate to the general practitioner was significantly higher than that to the doctor in the research unit (85% compared with 75%) and differed by age and sex. The results have important implications for other research workers and suggest that general practitioners are in a key position in the conduct of medical and epidemiological research.

Adult↗
PubMed1979

Practical work in a behavioural sciences course.

This paper describes a recent change in the practical component of the Behavioural Sciences course at Dundee Medical School. Results obtained from an evaluation of the change appear to show that students' learning was enhanced by the new form of practical work.

Behavioral Sciences↗
PubMed1979

Communication skills and undergraduate medical education.

This paper reports some aspects of teaching communication skills based on experience with over 100 pre-clinical students in each of two years. Students interviewed patients selected by general practitioner tutors from their practices and 214 interviews, recorded on videotape, were subsequently analysed. Without having been given detailed instruction, approximately two-thirds of each class of second year students (mean age 19 1/2 years) sustained a consultation for 5 minutes or more. Over one half of the students elicited the salient features of the patients' problems within this short time. Anxiety exhibited by the majority of students could be seen to influence the interviews in several ways. These manifestations and the ways in which the interview was affected are briefly described. When some of the patients were subsequently interviewed by postgraduate trainees in general practice, the consultations differed in a number of respects. These differences are described, and the possible significance of the observations is discussed in relation to medical education.

Anxiety↗