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Biomedical subjects

K R Swanson

Publications and source records attributed to K R Swanson.

5 recordsLinked to original sources
PubMed2001

A quantitative model for the dynamics of serum prostate-specific antigen as a marker for cancerous growth: an explanation for a medical anomaly.

Prostate-specific antigen (PSA) is an enzyme produced by both normal and cancerous prostate epithelial cells. Although PSA is the most widely used serum marker to detect and follow patients with prostatic adenocarcinoma, there are certain anomalies in the values of serum levels of PSA that are not understood. We developed a mathematical model for the dynamics of serum levels of PSA as a function of the tumor volume. Our model results show good agreement with experimental observations and provide an explanation for the existence of significant prostatic tumor mass despite a low-serum PSA. This result can be very useful in enhancing the use of serum PSA levels as a marker for cancer growth.

Adenocarcinoma↗
PubMed2000

A quantitative model for differential motility of gliomas in grey and white matter.

We have extended a mathematical model of gliomas based on proliferation and diffusion rates to incorporate the effects of augmented cell motility in white matter as compared to grey matter. Using a detailed mapping of the white and grey matter in the brain developed for a MRI simulator, we have been able to simulate model tumours on an anatomically accurate brain domain. Our simulations show good agreement with clinically observed tumour geometries and suggest paths of submicroscopic tumour invasion not detectable on CT or MRI images. We expect this model to give insight into microscopic and submicroscopic invasion of the human brain by glioma cells. This method gives insight in microscopic and submicroscopic invasion of the human brain by glioma cells. Additionally, the model can be useful in defining expected pathways of invasion by glioma cells and thereby identify regions of the brain on which to focus treatments.

Brain Neoplasms↗
PubMed1992

Treatment of unstable tibial shaft fractures by closed intramedullary nailing with flexible (Ender-type) pins.

Eighty patients with unstable tibial diaphyseal fractures were treated by closed intramedullary nailing with Ender-type flexible pins. The majority of injuries occurred from falling while snow skiing. Sixty-six fractures were closed and 14 were open. Fifty-eight fractures involved the distal, 21 fractures the middle, and one fracture the proximal one third of the tibial shaft. The average time to roentgenographic union was 15.5 weeks (range, ten to 34 weeks) for closed and open Grade I and II fractures. The time to union in Grade III fractures was 50 weeks (range, 36-64 weeks). There were two nonunions and two delayed unions. Both nonunions occurred in Grade IIIA open shaft fractures. Intramedullary stabilization with flexible, Ender-type pins provides good control of unstable tibial shaft fractures. The use of pins with a smaller diameter (3.5 or 4 mm) allows the surgeon to place more pins across the fracture site. The use of multiple pins and packing the intramedullary canal may provide better rotational stability. The use of Ender-type pins for fixation of Type IIIA open tibial shaft fractures is contraindicated.

Adolescent↗
PubMed1987

Training for Alpine skiing.

Skiing requires aerobic fitness. For aerobic conditioning, there must be significant elevation in heart rate during training. Although anaerobic training benefits physical fitness in general, skiing requires more aerobic than anaerobic conditioning. Strength, power, and endurance can be maintained through the use of concentric and eccentric contractions, using a variety of equipment and sports. Care should be taken to avoid injury to the patellofemoral joint during training. It is important to use specificity in choosing sports, as well as the exercise patterns in preseason training. If these principles are recognized in ski conditioning, a successful and effective training program will result.

Athletic Injuries↗