Induction of interleukin-2 receptor by tumor necrosis factor α on cultured ovarian tumor-associated lymphocytes

Summary We have recently reported that autologous tumor-specific cytotoxic T lymphocyte (CTL) lines and clones can be developed from lymphocytes infiltrating ovarian malignant ascites (TAL). In this study, we investigated the biological effects of tumor necrosis factor (TNF) in the induction, expansion, long-term proliferation and lytic function of CD8⁺ TAL. TNF up-regulated the IL-2 receptor (IL-2R) chain (Tac antigen) on the surface of CD3⁺ CD8⁺ CD4^– TAL, enhanced the proliferation of autologous tumor-specific CTL, and potentiated their lytic function in long-term cultures. Furthermore, in the induction and expansion phase of CD8⁺ TAL, the presence of TNF was associated with a selective increase in CD8⁺ IL-2R⁺ (Tac⁺) cells, and subsequent decrease in CD4⁺ IL-2R⁺ (Tac⁺) cells. These results suggest that the observed facilitation of the outgrowth of CD8⁺ cells in TAL cultures may be due, at least in part, to the up-regulation of IL-2R, and indicate the usefulness of TNF in the analysis of signalling in autologous tumor-reactive CTL.     

Efficient degradationin vitro of all intermediate filament subunit proteins by the Ca2+-activated neutral thiol proteinase from Ehrlich ascites tumor cells and porcine kidney

Vimentin, desmin, glial fibrillary acidic protein, neurofilament triplet proteins, and a mixture of cytokeratins were digested with Ca²⁺-activated neutral thiol proteinase isolated from Ehrlich ascites tumor (EAT) cells and porcine kidney. All intermediate filament proteins were degraded by the proteinase, although with different rates and Ca²⁺ optima. These results are in part at variance with our previous statement that the Ca²⁺-activated proteinase from EAT cells is specific for vimentin and desmin.     

The key role of residue 5 in angiotensin II

The conformation–biological activity relationships in a series of angiotensin II analogs substituted in position 5 were studied. Results indicated that only analogs with β-branched residue in position 5 possess spectral and biological properties identical to that of parent angiotensin II.     

Application of Response Surface Methodology to Evaluation of Bioconversion Experimental Conditions

Using Candida tenuis, a yeast isolated from the digestive tube of the larva of Phoracantha semipunctata (Cerambycidae, Coleoptera), we were able to demonstrate the bioconversion of citronellal to citronellol. Response surface methodology was used to achieve the optimization of the experimental conditions for that bioconversion process. To study the proposed second-order polynomial model, we used a central composite experimental design with multiple linear regression to estimate the model coefficients of the five selected factors believed to influence the bioconversion process. Only four were demonstrated to be predominant: the incubation pH, temperature, time, and the amount of substrate. The best reduction yields (close to 90%) were obtained with alkaline pH conditions (pH 7.5), a low temperature (25°C), a small amount of substrate (15 μl), and short incubation time (16 h). This methodology was very efficient: only 36 experiments were necessary to assess these conditions, and model adequacy was very satisfactory as the coefficient of determination was 0.9411.     

Metabolic heterogeneity of the proximal and distal kidney tubules

Proximal and distal tubule suspensions were prepared from kidneys of Sprague-Dawley rats by an isolation procedure on a Percoll^R gradient. The marker enzymes alkaline phosphatase (brush border) and hexokinase (cytoplasmic) as well as p-aminohippurate transport capacity, gluconeogenic activity and electron microscopy were used to characterize the two kidney tubule suspensions. The results of this study indicate that cytochrome P-450 is localized to the proximal tubular cells and that the O-deethylation of 7- ethoxycoumarin was higher in the proximal than distal fraction. Both proximal and distal tubules showed glucuronidation and deacetylation capacities and a relatively equal distribution of non-protein sulfhydryls. These studies demonstrate metabolic heterogeneity of the nephron, the proximal tubule being the main site of renal xenobiotic metabolism. Understanding of metabolic heterogeneity of proximal and distal kidney tubules should provide important information regarding cell specific mechanisms of nephrotoxicity.     

Effect of Sodium Chloride and pH on Enterotoxin C Production

Growth and production of enterotoxin C by Staphylococcus aureus strain 137 in 3% + 3% protein hydrolysate powder N-Z Amine NAK broths with 0 to 12% NaCl and an initial pH of 4.00 to 9.83 were studied during an 8-day incubation period at 37 C. Growth was initiated at pH values as low as 4.00 and as high as 9.83 at 0% salt level as long as the inoculum contained at least 10(8) cells per ml. Rate of growth decreased as the NaCl concentration was increased gradually to 12%. Enterotoxin C was produced in broths inoculated with 10(8) cells per ml and above and having initial pH ranges of 4.00 to 9.83, 4.40 to 9.43, 4.50 to 8.55 and respective NaCl concentrations of 0, 4, and 8%. In the presence of 10% NaCl, the pH range supporting enterotoxin C production was 5.45 to 7.30 for an inoculum level of 10(8) cells per ml and 6.38 to 7.30 for 3.6 x 10(6) cells per ml. In repeated experiments in which the inoculum contained 10(8) cells per ml, we failed to demonstrate enterotoxin C production in broths with 12% NaCl and a pH range of 4.50 to 8.55 and concentrated up to 14 times. The effect of NaCl on enterotoxin C production followed the same pattern as its effect on enterotoxin B production. As the concentration of NaCl increased from 0 to 10%, yields of enterotoxin B and C decreased to undetectable amounts.     

Epidemiology of Malignant Melanoma in Central Europe: Risk Factors and Prognostic Predictors. Results of the Central Malignant Melanoma Registry of the German Dermatological Society

The Central Malignant Melanoma Registry (CMMR) of the German Dermatological Society was established in 1983, and 7789 cutaneous malignant melanomas (CMM) were registered by 35 dermatological departments in Germany, Austria and Switzerland until the end of 1989. Population-based incidence rates, risk factors for developing CMM and prognostic parameters for predicting the final outcome were investigated in separate multicenter studies performed by the CMMR. Among the 7789 CMM registered, there was a preponderance of females (57.7%) versus males (42.3%). The age distribution peaked in the 5th and 6th decade of life for both sexes with a mean age of 52 years. The mean detection age was 50 years for superficial spreading melanoma, 53 for nodular melanoma, and 65 for lentigo maligna melanoma. Mean tumor thickness decreased from 2 mm in 1983 to 1.5 mm in 1989, indicating better CMM-awareness of the population and the medical community in this area. 90% of the patients presented with clinical stage I CMM without detectable metastases at first diagnosis. The incidence of CMM in Berlin (West) was assessed based on 960 cases diagnosed between 1980 and 1986. The incidence increased by 49% between 1980-81 and 1985-86, and the age standardized-incidence rate (European standard population) was 9.8 for males and 7.8 for females per 100,000 inhabitants and year in 1985-86. Mortality rates decreased in this period from 3.5 to 2.6 for males and slightly increased for females from 1.2 to 1.6 per 100,000 inhabitants and year. A case control study on the relative risk (RR) for developing CMM revealed the total number of melanocytic nevi (MCN) to be the strongest risk predictor (15x - 50x increased RR), followed by the presence of dysplastic MCN (7x increased RR) and the skin type I (2x increased RR). Interestingly, no differences between CMM-cases and controls were found with respect to the history of sunburns or other parameters of sun exposure in this study. Multivariate analysis of 5093 stage I CMM-patients from four departments with long-term follow-up revealed that tumor thickness is the strongest predictor of survival with an almost linear correlation to the risk of death for tumor thickness up to 6 mm with no further increase in mortality for higher tumor thickness. The best classification of tumor thickness for survival prediction was 1 mm, 1.01 ?2 mm, 2.01 ?4 mm and > 4 mm in our data set on 5093 patients. Sex was found to be the second most important prognostic factor showing a significant advantage for females. Furthermore, a high risk was identified for tumors localized on the upper trunk, upper arm, neck and scalp on the upper trunk, upper arm, neck and scalp (=TANS); the anatomical site, therefore, should be taken into account for a prognostic classification of primary CMM.