Vasoformative sarcomas arising from BALB/3T3 cells attached to solid substrates.

The BALB/3T3 mouse embryo cell line, noted for its marked postconfluence inhibition of proliferation, anchorage dependence, and high serum requirement, and frequently studied as a prototype nontumorigenic "fibroblast" line that is compared with tumorigenic sublines transformed with various agents, produced tumors within 2 to 3 months when an average of 3 X 10(4) cells were implanted s.c. attached to 1- X 5- X 10-mm polycarbonate platelets. Plastic platelets alone produced no tumors after 1 year of observation. The tumors, as well as others arising from implants of BALB/3T3 cells attached to 3-mm glass beads, were given the histological diagnosis of "vasoformative saroma" because the tumor cells frequently formed vascular channels. The vasoformative pattern and the results of specific staining for reticulin and collagen support the likelihood that BALB/3T3 cells originated from endothelial cells rather than from fibroblasts. That the tumors were derived from BALB/3T3 cells and not host cells was proved when tumors arising in BALB/c X C57BL/6 F1 hybrids were shown to be transplantable to BALB/c but not to C57BL/6 mice. The cultured tumor cells showed loss of both postconfluence inhibition of proliferation and anchorage dependence. Evidence of the induction of endogenous oncornaviruses was obtained in only one of four tumors tested. These tumors also exhibited tumor-unique transplantation rejection antigens. We conclude that BALB/3T3 cells are preneoplastic and give rise to different spontaneously transformed clones bearing unique tumor rejection antigens when implanted in vivo attached to a solid substrate.     

Urethral devices for managing stress urinary incontinence

Although surgery remains the gold standard for managing the majority of patients with stress urinary incontinence or retention, not all patients are suitable candidates or desire surgery. For these patients, several urethral caps and inserts are available, which are described. In approximately 50% of patients, satisfactory control is achieved. Further investigation undoubtedly will yield better devices to serve the large number of patients with urinary control problems.     

Impact of hollow-fiber membrane surface area on oxygenator performance: Dideco D903 Avant versus a prototype with larger surface area

This study compares the gas transfer capacity, the blood trauma, and the blood path resistance of the hollow-fiber membrane oxygenator Dideco D 903 with a surface area of 1.7 m2 (oxygenator 1.7) versus a prototype built on the same principles but with a surface area of 2 m2 (oxygenator 2). Six calves (mean body weight: 68.2 +/- 3.2 kg) were connected to cardiopulmonary bypass (CPB) by jugular venous and carotid arterial cannulation, with a mean flow rate of 4 l/min for 6 h. They were randomly assigned to oxygenator 1.7 (N = 3) or 2 (N = 3). After 7 days, the animals were sacrificed. A standard battery of blood samples was taken before the bypass, throughout the bypass, and 24 h, 48 h, and 7 days after the bypass. The oxygenator 2 group showed significantly better total oxygen and carbon dioxide transfer values throughout the perfusion (p < .001 for both comparison). Hemolytic parameters (lactate dehydrogenase and free plasma hemoglobin) exhibited a slight but significant increase after 5 h of bypass in the oxygenator 1.7 group. The pressure drop through the oxygenator was low in both groups (range, 43-74 mmHg). With this type of hollow-fiber membrane oxygenator, an increased surface of gas exchange from 1.7 m2 to 2 m2 improves gas transfer, with a limited impact on blood trauma and no increase of blood path resistance.     

Video urodynamic findings in men with the central cord syndrome

PURPOSE: The central cord syndrome reportedly has a favorable prognosis and rehabilitation outcome. However, to our knowledge the status of the lower urinary tract in patients with the central cord syndrome is unclear. We report on 22 men with the central cord syndrome who were evaluated by video urodynamics. MATERIALS AND METHODS: From 1986 to the present we identified 22 men with a mean age of 51 years who had the central cord syndrome and were included in the Houston Veterans Affairs spinal cord registry. All patients underwent video urodynamic evaluation a mean of 34.5 months after injury. RESULTS: Video urodynamic testing for vesicourethral dysfunction was normal in 3 patients, while it showed bladder outlet obstruction secondary to benign prostatic hyperplasia in 2, detrusor areflexia in 4, external detrusor-sphincter dyssynergia in 11, detrusor hyperreflexia with a synergistic external urethral sphincter in 1 and detrusor hypocontractility in 1. Urinary tract infection recurred in 3 patients with external detrusor-sphincter dyssynergia and urolithiasis developed in 2. CONCLUSIONS: Urodynamic testing revealed a high incidence of external detrusor-sphincter dyssynergia in men with the central cord syndrome. Due to the potential for upper tract deterioration all patients with the central cord syndrome should undergo baseline urodynamic studies. Those at high risk for upper tract deterioration with external detrusor-sphincter dyssynergia or a loss of compliance should be treated more aggressively with clean intermittent catheterization and anticholinergic medication when possible.     

Performance of Older Depressed Patients on Two Cognitive Malingering Tests: False Positive Rates for the Rey 15-item Memorization and Dot Counting Tests

To our knowledge, no investigations have been undertaken to determine whether depression impacts performance on two commonly used tests to detect malingering of cognitive symptoms, the Rey 15-item Memorization Test and the Rey Dot Counting Test. This is a critical issue because of the high rate of depressive symptoms in patients with neurological conditions. It was hypothesized that depressed individuals, especially those with more severe depression, might be at risk for failing the tests, because these patients exhibit mild deficits in mental speed, visual perceptual/spatial skills, and visual memory, abilities required for successful completion of the malingering tests. However, examination of test performance in 64 older participants with major depression generally revealed very low false positive rates for most test scores, and severity of depression was unrelated to test scores. These results add to accumulating data supporting the validity of these cognitive malingering tests by documenting few false positive identifications.