Biomedical subjects

Timothy B Boone

Publications and source records attributed to Timothy B Boone.

21 records · Page 2Linked to original sources

PubMed2002

Neurogenic bladder model for spinal cord injury: spinal cord microdialysis and chronic urodynamics.

We describe an animal model to study neurotransmitter changes in parallel with urodynamic testing following Spinal Cord Injury (SCI). Urodynamic access was achieved using a subcutaneously placed 7 French dual lumen portacatheter. Spinal cord injury was induced by weight drop technique onto exposed dura at T8. The L6-S1 detrusor nuclei were localized stereotactically and microdialysis probe placement was confirmed through histologic methods. Chronic urodynamics revealed detrusor hyperreflexia (DH) 14 days following SCI. In vivo microdialysis of spinal cord amino acids was performed using CMA 11 (240 uM) probes in halothane-anesthetized rats at baseline and intervals of 20-30 min following spinal cord injury. Significant increases in the excitatory amino acid glutamate, and the inhibitory amino acids, glycine and taurine, were seen following spinal cord injury. Amino acid levels peaked at approximately 40 min following contusion injury with glycine demonstrating the highest levels of all amino acids measured. This neurogenic rat model provides a useful means of examining the effects of spinal cord injury on bladder function. By utilizing spinal cord microdialysis, one could intervene at the level of the detrusor nuclei to modulate bladder function.

Animals↗

PubMed2002

Prostate cancer screening with prostate specific antigen in spinal cord injured men.

PURPOSE: As the spinal cord injured population ages, prostate cancer becomes a more significant cause of potential mortality. Consequently due to various bladder management techniques the validity of standard prostate specific antigen (PSA) screening values in this population must be evaluated. We compared screening PSA values in a large population of spinal cord injured patients with those in age matched, nonspinal cord injured men. MATERIALS AND METHODS: Screening PSA values were obtained using the AxSYM assay (Abbott Laboratories, Abbott Park, Illinois) in 366 spinal cord injured men 40 to 79 years old. In those with PSA elevated to greater than 4 ng./ml. who consented to further evaluation standard sextant needle biopsy of the prostate were performed under transrectal ultrasound guidance. Data were compared with data on 371 randomly selected, age matched controls from the Baylor College of Medicine community screening program database of more than 19,000 patient-tests. Analysis was performed with the unpaired Student t test. RESULTS: When we divided patients 40 to 80 years old into 4 age groups by decade and compared them with normal controls by decade, there was no statistically significant difference in mean PSA in the 2 groups. Of 18 spinal cord injured patients with PSA greater than 4 ng./ml. 12 underwent transrectal ultrasound guided needle biopsy of the prostate and 6 refused further evaluation. Five of these biopsies (1.3% overall) were positive and 7 were negative for adenocarcinoma. CONCLUSIONS: As in healthy men, PSA and digital rectal examination can be performed in spinal cord injured men to screen for prostate cancer. None of the various bladder management techniques in these cases seemed to affect screening results.

Adenocarcinoma↗

PubMed2002

Selecting a medical therapy for overactive bladder.

Immediate-release oxybutynin was the gold standard for pharmacologic treatment of overactive bladder for nearly 30 years. Intolerable systemic side effects, in particular dry mouth, limited its clinical utility, resulting in poor patient compliance with dosing regimens. Multiple studies have demonstrated the vastly superior tolerability of tolterodine, extended-release tolterodine, and extended-release oxybutynin over that of immediate-release oxybutynin at equivalent doses, and in the case of extended-release oxybutynin even to twice the dose of the original immediate-release form. With different drug delivery systems and, perhaps, with better bladder selectivity, these new oral agents have favorable side effect profiles, which translate into higher patient compliance and fewer treatment withdrawals or dosage reductions.

Journal Article↗