E-cadherin is a Ca(2+)-dependent intercellular adhesion molecule known to exert an invasion-suppressor function. In the present study, E-cadherin expression was immunohistochemically investigated in a retrospective series of 413 RO-resected gastric carcinomas using the monoclonal antibody (MAb) 5H9. Of these cases, 108 tumors revealed a preserved E-cadherin expression similar to that of normal gastric mucosa. In 95 tumors, E-cadherin expression was moderately reduced and in 86 tumors highly reduced. In 124 tumors, no or only a very weak dotted expression could be detected. There was a significant correlation between the degree of E-cadherin expression and the grade of tumor differentiation, as well as with histological type according to the Laurén and the WHO classifications. In contrast, no correlation could be demonstrated between E-cadherin expression and the prognostic parameters depth of invasion, lymph node involvement and vascular invasion. As shown by univariate Cox regression analysis, patients with E-cadherin-positive tumors had significantly better 3-and 5-year survival rates than patients with E-cadherin-negative tumors. This prognostic impact remained present in a multivariate Cox regression analysis, including the prognostic parameters pT category, pN category and vascular invasion.

Background. Mutations of the p53 gene belong to the most common genetic alterations in human cancer that have been implicated in tumorigenesis and tumor progression. Although p53 expression appears to be correlated with prognosis in patients with breast cancer and some other types of cancer, its prognostic role in gastric cancer is still uncertain. In the present study, therefore, the prognostic impact of p53 expression was evaluated in 418 patients with curatively resected gastric carcinomas without residual tumor (RO‐resection). Methods. Tumor sections of 418 RO‐resected gastric carcinomas were stained with the monoclonal antibody DO‐1 after microwave processing. p53 expression was statistically compared with clinico‐pathologic features and postoperative survival. Results. p53 expression was detected in 57.5% of all tumors, with strong inter‐ and intratumor heterogeneity. No immunoreactivity was observed in the normal mucosa adjacent to the tumor. Statistically, no significant correlation between p53 overexpression and depth of invasion, lymph node involvement, or grade of tumor differentiation was detected. The correlations with blood vessel invasion (P = 0.049) and lymphatic vessel invasion (P = 0.047) were of marginal significance. Survival analysis revealed no significant impact of p53 expression on survival, the 5‐year survival rates were 40.6% ± 7.8% for patients with p53 positive tumors and 49.2% ± 8.9% for patients with p53 negative tumors (P = 0.43). Furthermore, no correlation with survival was found when four different levels of p53 expression were analyzed (P = 0.51). p53 expression had no influence on survival, in either the lymph node positive or negative groups. Conclusions. The data suggest that the immunohisto‐chemical detection of p53 expression is at present not a predictor of outcome of patients with gastric cancer or to identify subgroups of patients who may be at higher risk.

Penile vibrostimulation (PVS), a noninvasive repeatable method, has been shown in the squirrel monkey to yield semen of higher quality than rectal probe electro‐ejaculation (RPE). The present study aimed at establishing the conditions for PVS to collect ejaculates from marmoset monkeys. Ten adult males were trained on the appropriate handling before each was subject to six to 12 PVS tests. Ejaculation was stimulated using a FertiCare® personal vibrator fitted with a 2 cm × 0.5 cm i.d. glass tube. The stimulus was repeatedly applied over a frequency of 75–95 Hz and amplitude of 1–2 mm for up to 20 min. Ejaculates were analyzed for volume, total sperm number, sperm concentration, and proportion of living and motile sperm. Ejaculates were obtained in 31 of 88 PVS tests; 87.1% of the ejaculations occurred at 80–85 Hz frequency and 1–1.5 mm amplitude. In 18 tests ejaculates were produced within 49.7 seconds. Ejaculates were characterized by (mean values): volume 31.9 μl, total sperm number 34.2 × 106/ejaculate, concentration 1,154.2 × 106 sperm/ml, live sperm 74.6%, motile sperm 59.6%. Total number and concentration of spermatozoa were significantly enhanced in singly living males. PVS yielded three to four times more spermatozoa than comparable previously published values for RPE. Enhancing the success rate by preselecting males for responsiveness may render PVS the sperm collection method of choice in marmoset monkeys. Am. J. Primatol. 52:149–154, 2000. © 2000 Wiley‐Liss, Inc.

Summary The prognostic significance of tumour cell proliferation was investigated in a series of 418 gastric carcinomas using the monoclonal antibody MIB-1. Owing to strong intratumoural heterogeneity of MIB-1 expression three different proliferation indices (PIs) were determined in all carcinomas: (1) PImax in areas of maximal tumour cell proliferation, (2) PIrand in areas randomly distributed over the whole tumour, (3) Plfront in areas exclusively located at the tumour invasion front. There was a strong intertumoral heterogeneity with

The availability of sufficient amounts of spermatozoa of high quality is one of the main limiting factors in reproductive research and development of reproductive technologies in marmoset monkeys (Callithrix jacchus). Penile vibrostimulation (PVS) has been successfully used in semen collection in the squirrel monkey but with poor success rate in the marmoset. We report here on an improved protocol for PVS with a success rate of almost 90%. Ejaculates obtained by PVS were of enhanced quality compared with those obtained by rectal probe electro-ejaculation (RPE). PVS ejaculates contained on average three to fourfold higher numbers of total and motile spermatozoa. Assessment of sperm kinematics using computer-assisted sperm analysis indicated that there are also functional differences between spermatozoa collected by PVS and RPE. Marmoset spermatozoa in samples obtained by RPE swim in a more convoluted manner compared with those obtained by PVS.