Bladder cancer arising in a spina bifida patient

We report the case of a 52-year-old patient with spina bifida, neurologic bladder, and a history of recurrent urinary tract infections (UTIs) in whom a bladder cancer was incidentally discovered. Cytology, cystoscopy, and cystography showed nonspecific, extensive inflammatory lesions. Cystography demonstrated a complex of diverticulae and cellules. Pathologic examination of a diverticulectomy specimen revealed a grade III pT3b transitional and squamous cell carcinoma. Because of the similar disease causation (recurrent UTIs, stones, and indwelling catheterization), we suggest extension of the guidelines proposed for patients with spinal cord injuries (ie, annual serial bladder biopsies) to patients with nontraumatic neurogenic bladder.     

Ultrasonic assistance in the diagnosis of hand flexor tendon injuries

In contrast to routine flexor tendon injuries, flexor tendon ruptures following blunt injury or re-ruptures following repair can be difficult to diagnose. The authors investigated the efficacy of using ultrasound to assist in the diagnosis. From 1996 to 1997, 8 patients underwent evaluation of the flexor tendons using an ATL HDI-3000 ultrasound machine with a high-resolution, 5 to 9-MHz hockey stick linear probe. Dynamic evaluation was performed in real time, simulating clinical symptoms. Six patients underwent surgical exploration. Sonographic diagnosis and intraoperative findings were correlated. Ultrasound was used to diagnose 3 patients with ruptured flexor digitorum profundus tendons. Mechanisms of injury included forceful extension, penetrating injury, and delayed rupture 3 weeks after tendon repair. Subsequent surgical exploration confirmed the ruptures and location of the stumps. Five patients had intact flexor tendons by ultrasound after forceful extension, penetrating injury, phalangeal fracture, crush injury, and unknown etiology. In 3 patients who underwent surgery for tenolysis, scar release, or arthrodesis, the flexor tendons were found to be intact, as predicted by ultrasound. The authors found ultrasound to be accurate in diagnosing the integrity of flexor tendons and in localizing the ruptured ends. They conclude that ultrasound is helpful in evaluating equivocal flexor tendon injuries.     

Differential effects of injections of anti-mu and anti-delta monoclonal antibodies on B-cell populations in adult mice: regulation of xenoreactive natural antibody-producing cells

BACKGROUND: The depletion of differential B cell and xenoreactive natural antibodies (XNA) by anti-delta and anti-mu injections was analyzed in adult mice. Sequential treatment with anti-delta and then anti-mu induces a complete depletion of B cells and XNA and represents a potential approach to induce xenograft tolerance. METHODS: Adult mice were injected with anti-mu, anti-delta, anti-delta then anti-mu, or control isotype monoclonal antibodies from day 0 to day 14. The different B-cell populations were analyzed by FACS and immunohistology. Ig production was tested by ELISA. XNA were analyzed by FACS. RESULTS: Anti-mu injections induced a depletion of IgMhigh, immature B cells, marginal zone B cells, and B1 cells and an increase of IgG-XNA production. Anti-delta injections induced mature conventional IgDhigh B-cell depletion and increased IgM-XNA production. Interestingly, sequential injections of anti-delta then anti-mu induced a depletion of immature B cells, mature B cells (MZ, B2, and B1), and XNA. CONCLUSIONS: These results demonstrate that mature B-cell depletion in adult mice can be obtained by mAb injections and depends on the surface immunoglobulin cross-linking threshold. Indeed, anti-mu mAb depleted IgMhigh B cells (MZ and B1) and anti-delta, IgDhigh B cells (B2). The differential B-cell suppression shows that conventional B cells are responsible in the IgG-XNA production and MZ and B1 cells in the IgM-XNA production. Sequential repeated injections of anti-delta then anti-mu mAb depleted all B-cell populations and suppressed the whole XNA production.     

Two mutations identified in the androgen receptor of the new human prostate cancer cell line MDA PCa 2a

PURPOSE: We have characterized the androgen receptor (AR) in a new human prostate cancer cell line, MDA PCa 2a, that has recently been established from a bone metastasis of a patient whose cancer exhibited androgen-independent growth. MATERIALS AND METHODS: Androgen responsiveness of these cells was assessed by measuring the effect of DHT and R1881 on cell growth and PSA secretion. Scatchard analysis was used to characterize the affinity and abundance of AR protein. Using a PCR based strategy, genomic DNA of the entire coding region of AR gene was sequenced to identify possible mutations. RESULTS: These cells express abundant AR (Nmax = 685 +/- 149 fmol./mg. protein), but the AR binding affinity (Kd) for DHT is only 25 nM, approximately 50-fold lower affinity than the mutated AR in LNCaP prostate cancer cells (Kd = 0.5 nM) or the wildtype AR in MCF-7 breast cancer cells (Kd = 0.4 nM). Two mutations, L701H and T877A, were identified in the ligand binding domain of the AR gene. Compared with LNCaP cells, the new cell line is significantly less responsive to DHT and R1881 as well as to other androgens such as testosterone, androstenedione, and DHEA. Similar to LNCaP cells, the ligand specificity of the AR in MDA PCa 2a cells appears to be relaxed and non-androgens such as progesterone and estradiol act as agonists although with less potency than in LNCaP cells. Interestingly, in the absence of androgens, the new cell line expresses 15-fold higher baseline levels of PSA than LNCaP. CONCLUSIONS: Two mutations were identified in the AR gene of the MDA PCa 2a cell line that are likely responsible for the decreased androgen sensitivity and altered ligand specificity observed in these cells. Thus, this new cell line with partial androgen responsiveness and PSA expression can serve as a functionally relevant model system of bone metastatic prostate cancer, and can be used to investigate the role of AR mutations in prostate cancer and its progression to androgen independence.