The effect of soy isoflavones on the development of intestinal neoplasia in ApcMin mouse.

Data from epidemiological studies suggest that isoflavones in soy may have a protective effect on the development of colon cancer in humans. Therefore, we have investigated whether soy isoflavones will inhibit intestinal tumour development in Apc(Min) mice. The mice were fed a Western-type high risk diet (high fat, low fibre and calcium) containing two different isolates of soy protein as a protein source. For the control and test groups this resulted in the administration of about 16 and 475 mg of total isoflavones per kg diet, respectively. As a positive control. a third group of mice was administered a low isoflavone diet supplemented with 300 ppm sulindac. No significant differences in the incidence, multiplicity, size and distribution of intestinal tumours were observed between Min mice fed low and high isoflavone-containing diets. However, a clear reduction in the number of small intestinal tumours was observed for the sulindac diet. Thus, in contrast to epidemiological studies, our results demonstrate that high amounts of soy isoflavones present in a Western-type high risk diet do not protect against intestinal tumour development in a relevant animal model such as the Min mice.

Assessment of recovery from ocular irritancy using a human tissue equivalent model.

The SKIN(2) ZK1200 tissue equivalent model has been used in an exploratory study of recovery from ocular irritation. Nine substances from the ECETOC eye irritation reference chemicals data bank were tested. The cellular viability of the tissue model was measured using the MTT assay immediately after chemical exposure and after incubation periods corresponding to observation times used in the Draize tests. The cellular viability of the tissue specimens exposed to moderate irritants, with modified maximum average score (MMAS) values between 15 and 40 (= 5), returned to control levels within 1-7 days. Tissue specimens exposed to 1 and 10% benzalkonium chloride showed significantly reduced MTT activities at day 14 and day 21. Mild ocular irritants, with MMAS values below 3 (n = 2), did not induce significant depressions of the MTT activities of the tissue specimens after 60 min exposure. A relatively good correlation (r = 0.73) was obtained between the exposure times used in vitro and Draize MMAS values. Moreover, the incubation periods needed for the exposed SKIN(2) ZK1200 to regain control MTT activities showed a good agreement (r > 0.90) with days-to-clear ocular irritancy in the Draize test.

Utility of preoperative serum prostate-specific antigen concentration and biopsy Gleason score in predicting risk of pelvic lymph node metastases in prostate cancer.

OBJECTIVES: To determine the accuracy of the preoperative serum concentration of prostate-specific antigen (PSA) plus the Gleason pathology score of biopsy specimens in predicting the presence of disease in the pelvic lymph nodes in patients with prostate cancer. METHODS: The medical records of all patients treated for prostate cancer at eight medical centers from January 1988 to June 1993 were reviewed. There were 932 patients with newly diagnosed prostate cancer for whom all relevant data were available who had undergone pelvic lymphadenectomy with (n = 912) or without (n = 20) radical prostatectomy. The rate of false-negative predictions of metastases based on combined preoperative biopsy Gleason score and serum PSA concentration was analyzed. A multivariate logistic regression analysis was performed to assess the value of preoperative serum PSA and biopsy Gleason scores individually and in combination in predicting pelvic lymph node metastases. RESULTS: The false-negative rate of metastases was 0% for preoperative PSA concentrations < or = 6 ng/mL and biopsy Gleason scores < or = 5 (n = 142) and 1.0% for PSA concentrations < or = 10 ng/mL and Gleason scores < or = 6 (n = 388). The 95% upper confidence limit for the rate of false negativity at this PSA cut-off level was 2.0%. A combination of preoperative serum PSA levels and biopsy Gleason scores provided the best prediction for the false-negative rates. CONCLUSIONS: For patients with newly diagnosed prostate cancer who have biopsy Gleason scores < or = 6 and preoperative PSA concentrations < or = 10 ng/mL (42% of our series), a staging pelvic lymphadenectomy appears to be unnecessary. The substantial cost associated with both cross-sectional imaging and staging lymphadenectomy may therefore be avoidable in this group of patients.

Renal trauma: re-evaluation of the indications for radiographic assessment.

We studied prospectively 359 consecutive patients with blunt (306) or penetrating (53) renal trauma to refine the indications for radiographic evaluation. Various factors, including the degree of hematuria, presence of shock and associated injuries easily assessable at the time of initial evaluation, were correlated with the severity of renal injury to determine whether any combination of parameters will separate patients with renal contusions from those with significant renal injuries (minor and major lacerations, and vascular injuries). We identified 3 groups: group 1-85 patients with gross hematuria or microscopic hematuria and shock after blunt trauma (including all 23 with significant renal injuries), group 2-221 patients with microscopic hematuria but no shock after blunt trauma (all with renal contusions) and group 3-53 patients with penetrating trauma. No combination of parameters was able to predict a severe injury in group 3. Our data support radiographic evaluation in groups 1 and 3. However, because all patients in group 2 had renal contusions and experienced no complications from nonoperative management we believe that excretory urography, which is time-consuming and costly, can be avoided in patients with microscopic hematuria but no shock after blunt renal trauma.

Primary transitional cell carcinoma of prostate.

Primary transitional cell carcinoma of the prostate (TCC-P) is a rare tumor for which definitive therapy remains undefined. To establish a basis for therapy, we analyzed 3 new cases and reviewed the literature. The following points were observed: (1) the true diagnosis is often missed at initial pathologic examination; (2) the tumor has a propensity for extensive local invasion; and (3) it commonly presents with obstructive symptoms in relatively young patients. Treatment recommendations based on our review include: maintenance of a high index of suspicion, especially for fifty to sixty-year-old men with prostate tumors or for suspected prostatic adenocarcinoma that is rapidly progressive and/or unresponsive to hormonal therapy; preoperative pelvic irradiation followed by radical cystoprostatourethrectomy is the treatment of choice in low-stage disease, and combined radiation therapy and chemotherapy should be used for disease beyond the prostate.

Rupture of the corpus cavernosum: surgical management.

Rupture of the corpus cavernosum is an uncommon injury resulting from a direct blow to the erect penis. The injury is easy to recognize but treatment remains controversial. Our uniform operative plan, consisting of immediate exploration, identification, sharp débridement and primary repair of the tear in the tunica albuginea with absorbable sutures, resulted in preservation of normal penile erection in 7 patients. The hospital stay was brief (mean 3.8 days) and there were no complications. These results compare favorably to operative management as reported in the literature. Conservative management is associated with a 29 per cent complication rate and a mean hospital stay of 14 days. Therefore, early surgical repair of the rupture is advocated.

Evaluation of patient's knowledge of diabetes self-care.

A survey conducted at a Veterans Administration Hospital to evaluate patient capability for self-management found that over 35 per cent of the patients interviewed lacked any formal training. Seventeen patients had been placed on insulin without formal instruction. Almost one half the patients who claimed to have attended training programs could not demonstrate adequate knowledge or skills in any of the major areas of self-care: insulin administration, urine testing, diet, foot care, and management of hypoglycemia and hyperglycemia. While patients with training were more knowledgeable than patients without training, the difference was slight. The results indicate the need for systematic analysis of patient knowledge and the evaluation of training programs on a continuing basis.