Biomedical subjects

M J Magee

Publications and source records attributed to M J Magee.

5 recordsLinked to original sources

PubMed1992

Video-assisted thoracic surgery: basic technical concepts and intercostal approach strategies.

Video-assisted thoracic surgery is emerging as a viable approach to a number of intrathoracic disorders. Technical difficulties related to improper instrument selection and suboptimal intercostal operative access can reduce the utility of, and the enthusiasm for, the video-assisted thoracic surgical approach. This report describes the intercostal access strategy and the instrument positioning that we now prescribe for many video-assisted thoracic surgical procedures. These approaches have become refined during the course of our experience with 467 patients undergoing video-assisted thoracic operations over the last 18 months.

Endoscopes↗

PubMed1992

Single dose oral fluconazole vs intravaginal terconazole in treatment of Candida vaginitis. Comparison and pilot study.

Candida vaginitis develops in approximately one-fourth of women in their childbearing years. Conventional management consists of antifungal creams or tablets/suppositories administered intravaginally. Many patients have stated preferences for oral therapy. A randomized, double-blind placebo trial compared the efficacy of a single oral 200 mg dose of fluconazole with the application of terconazole 80 mg vaginal suppository daily for 3 days. Twenty-two patients (fluconazole = 12, terconazole = 10) were evaluated during a four-month period and favorable clinical responses were observed at both early and late evaluations. Mycologic cure was attained by 75% of the fluconazole group and 50% of the terconazole group at the early evaluation. At the late evaluation, mycologic cure was 75% and 100% respectively. The mean time to onset of symptom relief was 2.4 (1.7) days for the fluconazole group and 1.8 (1.8) days for the terconazole group. The mean time to complete relief of symptoms was 6.08 (2.84) and 6.6 (2.95) days respectively. A statistically significant difference did not exist for any of these measures. Seventy-three percent of the patients preferred oral therapy.

Administration, Intravaginal↗

PubMed1991

A computer-assisted image processing method for determining relative cardiac function in the chick embryo.

The general objective of this study was to develop a noninvasive method for efficiently and reproducibly determining relative cardiac function parameters in the chick embryo. The specific objectives of the study were 1) to develop several methods for computer-assisted image processing and quantitation of relative intraventricular blood volumes in the 3-day-old embryonic chick heart and 2) to compare methods for precision and with a previously established manual processing method. Images of the embryonic chick heart in ovo were recorded on videocassette tape, digitized, and enhanced by computer-aided histogram equalization. The area occupied by blood within the common ventricle was extracted by region-growing and spurious region removal algorithms and defined by the determination of edge-pixel coordinates. Edge-pixel coordinates of the longitudinal and transverse axes of the common ventricular blood region were located by three different methods, the lengths of the axes calculated, and volumes computed from the equation for determining volume of a prolate spheroid. Twenty-five images of the embryonic heart were randomly selected and processed. Volumes were calculated with each of the three methods on six different occasions. A coefficient of variation was calculated for each method. The intraobserver mean coefficient of variation for each method was 7.4%. When a 2-way ANOVA was conducted, mean coefficients of variation did not differ significantly for the three methods. However, computer processing (in addition to significantly reducing the time required to generate data) reduced the coefficient of variation observed in manual processing by 56.5%.

Analysis of Variance↗

PubMed1989

Suppression of the elicitation of the immune response to alloantigen by ultraviolet radiation.

Previous studies have established that exposure of mice to ultraviolet radiation followed by injection of alloantigen can suppress the induction of delayed hypersensitivity and the rejection of allografts in an antigen-specific manner. In the clinical situation, however, UV irradiation several days prior to transplantation may prove impractical due to the difficulty in predicting when a donor organ will be available. Thus, the purpose of this study was to determine if exposure to UV radiation can suppress the elicitation of the immune response in mice sensitized with alloantigen. The data demonstrate that exposure of mice to UV radiation 1, 3, or 5 days after the injection of alloantigen can significantly suppress the delayed hypersensitivity response to that alloantigen. Present in the spleens of these mice are suppressor T lymphocytes. These suppressor cells are specific for the antigen originally used to sensitize the mice, in that they do not suppress the response to an irrelevant alloantigen. In addition, spleen cells from mice sensitized with alloantigen and exposed to UV radiation 1, 3, or 5 days later are unable to proliferate in response to the alloantigen in a mixed lymphocyte response. These cells do respond to irrelevant third-party cells, demonstrating again the specificity of the suppression. These data demonstrate that exposure of mice in vivo to UV radiation can inhibit the elicitation of the immune response to alloantigen. Since the immunosuppression is specific for the sensitizing antigen, these data suggest that this may provide a novel method of suppressing the immune response to tissue allografts.

Animals↗

PubMed1989

Inhibition of the immune response to alloantigen in the rat by exposure to ultraviolet radiation.

Exposure of mice to ultraviolet radiation (UV) followed by alloantigen sensitization can suppress the immune response to that alloantigen. In order to assess the applicability of using UV-induced immunosuppression in organ transplantation, the effectiveness of UV in prolonging the survival of vascularized organ allografts must be determined. Because, for technical reasons, rats are better suited than mice for such experiments, we first wanted to determine whether UV suppresses the immune response of inbred rats to alloantigens. The data presented here demonstrate that exposure of rats to UV (115-129 kJ/m2) prior to alloantigenic sensitization decreases the mixed lymphocyte response to alloantigen. The depression of the proliferative response to alloantigen was selective in that spleen cells from the UV-treated rats could respond to mitogenic stimulation. In contrast to previous results with mice, suppressor cells could not be demonstrated in the spleens of the UV-treated rats. In addition, UV treatment after sensitization inhibited the response to alloantigen. These data suggest that treatment of the recipient with UV before or after alloantigenic sensitization may provide a novel method of inhibiting immune responses to allogeneic antigens.

Animals↗