PubMed Health⌕ Search

Biomedical subjects

K M Fitzsimmons

Publications and source records attributed to K M Fitzsimmons.

5 recordsLinked to original sources

Pathology and probability. Likelihood ratios and receiver operating characteristic curves in the interpretation of bronchial brush specimens.

Diagnoses in pathology often are qualitative, such as atypical or suspicious, and consequently are thought to have limited clinical value. To investigate the utility of a qualitative diagnostic system, seven pathologists retrospectively evaluated 100 bronchial brush specimens using the following categories: definitely benign, probably benign, possibly malignant, probably malignant, and definitely malignant. The likelihood ratio (LR) and receiver operating characteristic (ROC) curve, two statistical probabilistic measurements, were used to calculate diagnostic accuracy among individuals and groups. The results show: (1) the LR for individual diagnostic categories varied among observers, resulting in different clinically malignant probabilities; (2) observer experience did not appear to play a role in overall diagnostic accuracy, except in the diagnosis of small cell carcinoma; (3) observers operate at higher levels of diagnostic accuracy with, rather than without, clinical history. The authors conclude that qualitative diagnoses contain important information and can be interpreted effectively with LR and ROC.

Bronchi↗

Production of the cytokines interleukin 1 and 6 by murine brain microvessel endothelium and smooth muscle pericytes.

Murine brain microvessel endothelial cells and smooth muscle/pericytes (SM/P) cells were cultured from newborn BALB/c (normal strain) and SJL/j (autoimmune-prone strain) mice. These cells were evaluated for their ability to produce interleukin (IL)-1 and IL-6 cytokines. The expression of mRNA for IL-1 and IL-6 was shown in highly purified BALB/c endothelial cells and SM/P cells using polymerase chain reaction with specific primers for IL-1 alpha, IL-1 beta and IL-6. IL-6 but not IL-1 mRNA was detected in unstimulated SJL/j brain microvessel cells. The presence of IL-1 and IL-6 mRNA in the BALB/c brain microvessel endothelial cells and SM/P was confirmed by in situ hybridization. By D10.G4.1 assay, unstimulated BALB/c endothelial cells were shown to produce active IL-1 to a higher degree than SM/P. By B9 bioassay, a low amount of active IL-6 was detected in the supernatant of endothelial cells and SM/P. The production of IL-1 and IL-6 in the bioassays was upregulated by lipopolysaccharide (LPS) activation of the cells in a time- and dose-dependent way. IL-6 production was also shown to be upregulated by IL-1 beta activation of the cells. Brain microvessel endothelial cells of SJL/j origin released equivalent amounts of IL-6 compared to endothelial cells of BALB/c origin. However, the production of IL-6 was markedly higher in SM/P of SJL/j origin than in those of BALB/c origin. These observations, together with our previous data showing that brain microvessel SM/P cells produce GM-CSF, emphasize the possibility for active participation of brain microvasculature SM/P as well as endothelium in inflammatory reactions of the central nervous system.

Animals↗

Effects of carbohydrate loading and weight-lifting on muscle girth.

Bodybuilders have used different carbohydrate loading regimens in conjunction with resistance exercise prior to competition in the belief that this would result in increased muscle size. To investigate this possibility, muscle girth measurements were obtained from nine weight-trained males before and after a control (standard isocaloric diet) and an experimental trial (carbohydrate loading). The latter regimen consisted of 3 days of intense weight-lifting while the subjects ingested a diet of 10% carbohydrate (CHO), 57% fat (F), and 33% protein (P), followed by 3 days of light weight-lifting and a day of rest while ingesting a diet of 80% CHO, 5% F, and 15% P. The control trial consisted of an identical weight-lifting regimen while subjects ingested an isocaloric (45 kcal/kg BW/day) diet. Body weight and girths (forearm, upper arm, chest, thigh, waist, and calf) were obtained before and after each trial in a relaxed and flexed state. The results indicate that an exercise/carbohydrate loading regimen had no significant effect on muscle girth as compared to the control trial. It is concluded that CHO loading has no additional advantage to enhancing muscle girth in bodybuilders over weight-lifting alone.

Adipose Tissue↗

Disposable jet nebulizers. How reliable are they?

We studied the frequency of malfunction, variability in rate of nebulization, and effect of this variability on aerosol particle size of eight disposable jet nebulizer models produced by six manufacturers. Four of eight models showed visual signs of malfunction, including spraying of large, individually visible droplets, leaking of nebulizer solution, and air leaks that completely prevented nebulization. Variability of nebulization rate within specific models ranged from 57 to 129 percent. The model with the largest variability of nebulization rate was also associated with an unacceptably large variability in particle size. In contrast, two models with smaller variability in nebulization rate had greater consistency of particle size. These results indicate poor quality control by some manufacturers in the disposable nebulizer industry. The data suggest that purchasing agents should consider reliability as well as cost before selecting a specific nebulizer model and that their evaluation should include physical testing of multiple units of each model under consideration.

Disposable Equipment↗