Taurolithocholate increases heme catabolism and alters the clearance of antipyrine in the rat

Taurolithocholate has been implicated in human cholestatic syndromes. Its action is believed to be due to an alteration in liver plasma membrane composition. To investigate whether other membranes are similarly affected, we studied the effect of taurolithocholate on hepatic heme turnover by means of a new 14CO breath test. Between 2 and 7 h after taurolithocholate administration, 14CO production was significantly increased, suggesting increased heme catabolism. This was substantiated by the finding of a 47% reduction of microsomal cytochrome P450 content 3 h after taurolithocholate administration. There was a reciprocal increase of 50% in heme oxygenase activity, the key enzyme in heme catabolism. To probe the biological significance of these findings, we measured plasma disappearance of propranolol and antipyrine. Clearance of neither propranolol nor antipyrine was altered by acute taurolithocholate administration. Prolonged administration of taurolithocholate, by contrast, decreased metabolic clearance rate of antipyrine by 48%. This was accompanied by a 25% decrease in microsomal cytochrome P450 content. Our findings suggest that taurolithocholate affects composition and function of the smooth endoplasmic reticulum, and that its action is not limited to the liver plasma membrane.

Influence of common bile duct cannula size on maximal secretory rate of taurocholate in the rat

The common bile duct of male Sprague-Dawley rats was cannulated with either PE 10 or PE 50 tubing. Maximal secretory rate of taurocholate averaged 389 +/- 67 (SD) and 657 +/- 115 nmoles X min-1 X g liver-1 in the PE 10 and PE 50 group, respectively (p less than 0.005). Maximal bile secretory pressure was significantly higher in the PE 10 group (240 +/- 28 vs 174 +/- 8 mm H20; p less than 0.005). When the maximal secretory rate was exceeded, bile flow decreased in both groups but this was accompanied with a decrease in maximal bile secretory pressure in the PE 10 group only. Maximal secretory rate of bile salts is markedly influenced by experimental technique. Use of small caliber common bile duct cannulae leads to partial obstruction and decreases the apparent maximal secretory rate for taurocholate.

Taurocholate, but not taurodehydrocholate, increases biliary permeability to sucrose

To determine whether bile salts alter the permeability of the biliary tree to inert solutes, we investigated the effects of taurocholate and taurodehydrocholate on [14C]sucrose bile-to-plasma ratio in the situ perfused rat liver. Sucrose bile-to-plasma ratio remained virtually constant over a 3-h period in untreated rats. Infusing increasing amounts of taurocholate produced the anticipated dose-dependent increase in bile flow and bile salt secretion up to a maximal secretory rate of 278 nmol X min-1 X g liver-1. When the secretory rate was exceeded, bile flow decreased by 22%. Even at doses below the maximal secretory rate, sucrose bile-to-plasma ratio increased in a dose-dependent fashion. To determine whether this was due to recruitment of more permeable centrizonal hepatocytes, the effect of equimolar amounts of taurodehydrocholate was determined. This nonmicelle-forming bile salt led to more marked choleresis than taurocholate but did not affect sucrose bile-to-plasma ratio. We conclude that taurocholate, but not taurodehydrocholate, leads to a dose-dependent increase in biliary permeability.

Radical mastectomy versus radical mastectomy plus internal mammary dissection. Ten year results of an international cooperative trial in breast cancer

A multicentric randomized trial evaluated the interest of internal mammary dissection on operable breast cancer patients. One thousand four hundred and fifty-three patients were included in the study and were followed for ten years. There is no difference in survival or in relapse-free survival between the two groups. There were significantly more local recurrences in the group without internal mammary dissection, but these recurrences occurred mainly on patients who developed metastases. A great difference between centers was observed in the number of nodes examined and there is therefore a difference in the prognostic value of the number of nodes invaded.

Radical mastectomy versus radical mastectomy plus internal mammary dissection. Five-year results of an international cooperative study

From 1963 to 1968, the international group collected 1580 cases of breast cancer, randomized into two therapeutic groups: radical mastectomy and extended mastectomy. The data were processed on the UNIVAC 1107 computer of the I.N.S.E.R.M. Computing Center. No significant difference was observed between the two groups in the overall five-year survival rate. However, a more detailed analysis, according to certain prognostic features, showed that extended mastectomy improved the results in one subgroup: cancers of inner or medial quadrants, axillary N+. Within this group the difference was highly significant for a smaller subgroup (190 patients) including only tumors T1 and T2. In conclusion, there is no indication for extended mastectomy in any cancers of the outer quadrants or in those of the inner or medial quadrants without axillary involvement. A limited indication for extended mastectomy may be provisionally retained for T1 and T2 cancers of the inner or medial quadrants with axillary involvement.

[Current data on radiotherapy of breast cancer]

At the Symposium in Teheran two aspects of radiotherapy in mammary cancer came up for discussion: post-operative radiotherapy and the possibilities of conservative treatment, combining tumorectomy ("lumpectomy", "tylectomy ") for stage 1 cases. The place of post-operative irradiation was discussed in relationship to the appearance of local recurrences, metastases and the survival rates available from published data (therapeutic trials and retrospective studies) and in relationship with a population of 206 cases treated at the Gustave Roussy Institute between 1963 and 1966. The possible relationship between post-operative irradiation and immunity were mentioned. With identical wide surgical excision the essential role of post-operative irradiation consists of diminishing in a significant fashion the level of local recurrences. With more restricted surgery of the simple mastectomy type one asks whether irradiation could not replace radical node dissections. It should be reserved for the bad N+ cases. A retrospective study of 44 cases coded T1 NO/N1 MO/PevO treated by tumorectomy and cobalt 60 was compared with 44 matching cases which differed only in their local treatment which consisted of wide surgical excision. The survival actuarial rate at 8 years is 88.6% for the more conservatively treated group compared with 73% for the radical group. In order to provide a quite impartial result a WHO therapeutic trial was begun in 1972.