Clinicopathologic analysis of carcinoma of the breast in an African population.

A ten-year survey at Kinshasa University Hospital, Zaire, has shown that carcinoma of the breast is relatively common and accounts for 23% of all solid cancers in women. In most respects the growth is similar to that seen elsewhere. However, certain features not usually reported were noted: (1) Patients in Zaire are, overall, about ten years younger than those seen in western populations. (2) Compared with western data, the disease here is significantly associated with multiparity and breast-feeding. The reasons for these differences are not clear at present.

Role of metabolic overload in the initiation of DNA synthesis following partial hepatectomy in the rat.

Changes in hepatic ATP energy charge (EC = ATP +0.5 ADP/ATP + ADP AMP) as an expression of metabolic overload and oxidative phosphorylation were studied conjointly with DNA synthesis after partial hepatectomy (PH) in the male rat. ATP and EC showed a significant decrease while mitochondrial phosphorylative activity was enhanced within 24 h. Confronted with the pattern of DNA synthesis, the above changes were clearly separated in time from the actual process of DNA synthesis. Fasting delayed the recovery of EC as well as the peak value in the rate of thymidine incorporation. Extended glucose infusion prevented the drop of ATP during the entire period of treatment and considerably reduced fat infiltration and glycogen breakdown. In these glucose-infused rats, unchanged blood sugar was associated with tendency for plasma insulin to rise and suppression of the usual posthepatectomy hyperglucagonemia. With these metabolic and hormonal changes, an important delay in the onset and modification of the whole pattern of DNA synthesis were observed. The latter process began consistently only after a late fall of ATP which followed the cessation of glucose infusion. It is suggested that changes in energy metabolism, taken as an expression of hepatocyte metabolic overload following PH, account for the early events involved in the initiation of DNA synthesis, and probably regulate hepatocyte response to systemic hepatotrophic factors.

Fatal metastatic cystosarcoma phylloides in a young woman. Report of a case.

A fatal metastatic cystosarcoma phylloides occurred in an 18-year-old woman. The rapid increase in the tumor size and the histologic pattern shifting to an entirely sarcomatous growth contrasted with the maintenance of good general condition for several months. The hazards of conservative surgery in developing countries are discussed in the framework of this rare case in this age group.

Oxidative phosphorylation, enzyme induction and rat liver regeneration: effect of phenobarbital.

In order to outline the relationship between oxidative phosphorylation, enzyme induction and rat liver regeneration, the effect of one single dose of phenobarbital (PB) on hepatic mitochondria, microsomes and DNA synthesis was investigated. Experiments were performed on intact and partially hepatectomized rats. Results and conclusions can be summarized as follows: (1) While PB has no consistent effect on mitochondrial respiration either in normal or in partially hepatectomized rats, it clearly enhances at the rate of DNA synthesis in hepatectomized rats at 24 h. This suggests that the effect of PB on DNA synthesis is independent from the mitochondrial ATP generating activity. (2) PB causes the accumulation of cytochrome P-450 in intact rat hepatocytes, but this effect is suppressed by partial hepatectomy during the first 24 h. This and the above observation on mitochondria suggest that enzyme induction in these experimental conditions is not associated with an increase in mitochondrial oxidative phosphorylation. (3) The mechanism of the influence of PB on DNA synthesis is unclear, but present data suggest that in one single dose PB may behave in two different ways: in intact liver it causes the accumulation of cytochrome P-450 and in partially resected liver it enhances the rate of DNA synthesis; mitochondria playing apparently no important role in this interaction.

Stimulltion of mitochondrial phosphorylative activity in the regenerating rabbit liver following oral antibiotic treatment.

In this investigation, oral Kanamycin was administered to young male rabbits for 3 days, the control group receiving only water. Partial hepatectomy was then performed in all of them, and mitochondrial activity, energy charge and portal vein ammonia were measured at 12 and 24 h postoperatively. It was found that mitochondria from oral Kanamycin-treated rabbits have higher respiratory control ratios, higher state 3 respiration and higher P/O ratios than the control group, suggesting a further enhancement of phosphorylative activity. Energy charge in the Kanamycin-treated group showed less acute changes suggesting a positive balance in the energy status of those livers. The ammonia level here was much lower than in the control group. These findings suggest that the removal or the decrease of the overloading effect of ammonia resulting from bacterial activities in the intestine, has a beneficial effect on the healing process in liver surgery.

Cancer of the large bowel in the African: a 15-year survey at Kinshasa University Hospital, Zaïre.

In a 15-year survey at Kinshasa University Hospital, 954 solid cancers were recorded. Among these, 46 malignant tumours arose in the colon, rectum and anal canal, a proportion of 4-8 per cent. A review of the patients' age and clinical presentation, and pathology and aetiology of the tumours revealed that: 1. The incidence of this cancer in young Africans is higher than in Western countries. 2. The clinical presentation of this illness in young people is frequently unusual, but older African patients commonly present with classic symptoms. 3. The incidence of mucous carcinoma tends to be higher, but could be explained by the larger number of young people suffering from the condition. 4. Intestinal amoebiasis was associated with cancer in 3 cases. Its significance remains uncertain.