[Spindle cell carcinoma of the breast with neuroendocrine differentiation. A rare entity simulating a benign tumor]. / Carcinome mammaire à cellules fusiformes et différenciation neuro-endocrine. Une entité rare pouvant simuler une tumeur bénigne.

We report a case of spindle cell carcinoma of the breast with neuroendocrine and mucinous differentiation. Histological diagnosis can be difficult as macroscopic appearance and low grade cytologic features suggest a benign tumor. Differential diagnosis with a fusiform benign tumor of myoepithelial origin should be discussed. Immunohistochemistry is essential to confirm the diagnosis.

[Volvulus of the superior mesenteric area and congenital variation of the colonic fixation. Human Ontogenesis and Physiopathology. Apropos of a case in an adolescent]. / Volvulus du territoire mésentérique supérieur et variation congénitale de fixation colique. Ontogenèse Humaine et Physiopathologie. A propos d'un cas chez un adolescent.

Volvulus of the superior mesenteric territory involving the left and transverse colon is rare. Congenital variations of intestinal fixation have been implicated. We report a case observed in an adolescent which illustrates this hypothesis. There was a fixation of pancreatosplenic region and the left colic angle. The duodenopancreas and the right, transverse and left colon were mobile. Human ontogenesis of the colon could provide a pathophysiologic explanation. During foetal development, the intestine results from unequal growth of the different segments which undergo pressure from the different intra-abdominal contents. The fixation of the different parts of the intestine are independent from each other. Specific circumstances are required for variations in congenital fixation of the colon to led to late events responsible for mechanical volvulus.

Consequences of hormone-induced desensitization of adenylate cyclase in intact cells.

A hypothesis on the role of the hormone-induced desensitization of adenylate cyclase is proposed. It is suggested that the desensitization process could provide the cell with a highly efficient cyclic AMP system for transmitting hormone stimulus without requiring a large energy consumption. Theoretical considerations show that in fact the desensitization phenomenon allows the cyclic AMP system to present a good compromise between the efficiency and economy requirements of the cells.