Biomechanical analysis of the brachioradialis as a donor in tendon transfer

Anatomic and biomechanical properties of the passive brachioradialis muscle were investigated to understand the limited excursion of this muscle seen during tendon transfer surgery. First, architectural measurements were performed on three fiber bundles obtained from four regions of the brachioradialis (10 specimens) chosen to represent the range of muscle fiber lengths across the brachioradialis. Next, in separate specimens (eight specimens), passive excursion was measured by securing the distal tendon stump to a servomotor. A constant load of 4.9 N was applied to the tendon, while the distal tendon was released from the surrounding tissue in 3-cm increments. Within the four regions studied, muscle fiber length varied significantly from 104.2 +/- 6.2 mm to 179.8 +/- 6.1 mm. As the brachioradialis was released, an average of 3 mm of mobility was obtained for each interval whereas for the succeeding three intervals, an average of 5.3 mm of mobility was obtained. This resulted in 22.2 +/- 2.3 mm of mobility when each specimen was fully released. These data show that there is no intrinsic muscle fiber length limitation to excursion, but that excursion is limited by other intermuscular connections to adjacent connective tissue and other muscles.     

Association between Low Plasma Tryptophan and Blackouts in Male Alcoholic Patients

Alcohol has been observed to alter various aspects of memory function. Some of the most extreme forms of memory impairment experienced by alcoholics are blackouts. There are at present very few data on the biological mechanisms underlying alcohol-related memory impairment A variety of mechanisms including the cholinergic and catecholaminergic systems have been implicated in learning and memory. More recently, however, the importance of the serotonergic system in memory function has been demonstrated. We investigated whether patients with a history of blackouts had lower plasma levels of the serotonin precursor tryptophan than patients without such a history. Tryptophan values were significantly lower in patients who had experienced blackouts than in patients who had not No significant differences between the two group of patients were observed for other amino adds sharing with tryptophan the same transport carrier into the brain. Drinking history variables did not differentiate among the two patient groups. Our data suggest that a decrease in plasma tryptophan (and concomitant lowered brain serotonin) could increase the vulnerability of certain individuals to manifestations of various aspects of memory impairment mdudrng one of its most extreme forms, the blackout     

Monitoring intravesical therapy for superficial bladder cancer using fluorescence in situ hybridization

PURPOSE: We evaluated fluorescence in situ hybridization (FISH) for assessing the response to therapy in patients with superficial bladder cancer receiving bacillus Calmette-Guerin or other intravesical therapies. MATERIALS AND METHODS: A total of 37 patients receiving intravesical therapy for superficial bladder cancer were enrolled in this study. Urine specimens were collected for FISH analysis just prior to the first intravesical therapy in 31 cases and just prior to or within 2 months following the last intravesical therapy in 37. FISH was done using the UroVysion probe set (Abbott Laboratories, Abbott Park, Illinois) with results considered positive if 5 or more cells demonstrated polysomy. Biopsy, cystoscopy and/or cytology results were then compared to FISH results to evaluate the usefulness of the test for monitoring intravesical therapy. RESULTS: Of the patients 25 had a negative and 12 had a positive post-therapy FISH result. All 12 patients with a positive post-therapy FISH result had tumor recurrence, while tumor recurrence was observed in 13 of the 25 with a negative post-therapy FISH result (HR 4.6, 95% CI 1.9 to 11.1, p <0.001). Of the patients with tumor recurrence 7 of 12 with a positive post-therapy FISH result had muscle invasive tumor and 2 of 25 with a negative post-therapy FISH result had muscle invasive tumor (HR 9.4, 95% CI 1.9 to 45.3, p = 0.001). CONCLUSIONS: FISH appears to be useful for monitoring patients with superficial bladder cancer for the response to intravesical therapy. Patients with a positive FISH result at the end of treatment are at high risk for progression to muscle invasive bladder cancer.     

Functional angiography

The discovery of X-rays over a century ago enabled noninvasive examination of the human body. Contrast agents that enhanced X-ray images were soon developed that advanced angiology by allowing exploration of the vascular tree. Starting as a diagnostic tool, angiography underwent technological transformations over the last century and became a basis for interventional therapy as well. Initially a static two-dimensional record of the vasculature on screen films, angiography has evolved to real-time two-dimensional display of the vasculature on television monitors, three-dimensional reconstruction from computerized tomographic (CT) scans, and, more recently, three-dimensional cone-beam reconstruction. Cinematographic angiography is referred to as dynamic angiography in current terminology, but it essentially provides no more than images of vascular structures and changes therein. Although dynamic angiography has facilitated advances in image-guided interventions, the evaluation of blood flow rate, or perfusion, and blood flow velocity using angiography remains elusive. Many lines of research have been pursued toward enabling such evaluations, but none have found their way into clinical practice. This article reviews angiographic flow assessment methods attempted over the past several decades and explores some new avenues that may facilitate the transfer of such methods into the clinical practice of diagnostic and interventional angiography and, eventually, contribute to better patient care.     

Partial nephrectomy: Mayo clinic experience 1957–1977

Three hundred and six partial nephrectomies were performed at Mayo Clinic between 1957 and 1977. Operative and postoperative risks were analyzed according to the indication for surgery, type of partial nephrectomy performed, and other factors. The results demonstrate that partial nephrectomy performed by modern techniques is safe, with acceptable operative time, operative blood loss, and postoperative hospital stay. Complications encountered also were investigated. One death occurred, 8 delayed nephrectomies were required, in 2 patients delayed renal hemorrhage developed, 10 had urinary fistulas or urinomas, and in 16 patients wound infections developed. Study of the techniques used in those cases with postoperative complications suggests several approaches to reduce still further the morbidity of partial nephrectomy.