[Santiago Ramón y Cajal - Neuroanatomist, Artist and Writer]. / Santiago Ramón y Cajal ­ Neuroanatom, Künstler und Literat.

Santiago Ramón y Cajal came from North Spain and was very talented in painting and writing. Actually he wanted to become a painter but his father, who was a medical doctor himself, forced him to study medicine. In the end, he became a famous neuroanatomist, developed the neuron theory and, together with Camillo Golgi, was awarded the Nobel Price for medicine in 1906. In his career, he was very much supported by German scientists, especially by the Würzburg anatomist von Koelliker. He also displayed a lively literary activity. But most of his works are little known to us. Of his 5 "Cuentos de vacaciones" (vacation stories) there is a translation into English only since 2001.

Expression of CDX2 and MUC2 in Barrett's mucosa.

Barrett's mucosa is a risk factor for esophageal adenocarcinoma and should be detected at an early stage. It is defined by the presence of columnar epithelium with goblet cells in the lower esophagus, but histologic diagnosis can be uncertain in the absence of distinct goblet cells. We investigated 55 biopsies from 48 patients with endoscopically plain Barrett's esophagus and performed immunohistochemistry for CDX2 and MUC2. In addition, alcian blue (pH 2,5)/PAS staining was done. In histologically unequivocal Barrett's mucosa, nuclear expression of CDX2 in goblet cells and many columnar cells, as well as cytoplasmic positivity for MUC2 in goblet cells, could be observed. Alcian blue (pH 2,5)/PAS stained acidic mucins in goblet cells and in some non-goblet columnar cells. In six cases, no definite Barrett's mucosa was present, and no expression of MUC2 could be observed. In these biopsies, there was granular cytoplasmic and/or focal nuclear staining for CDX2 in non-goblet columnar epithelial cells, indicating their intestinal differentiation. We suggest that this peculiar mucosa is the precursor of unequivocal Barrett's mucosa and would designate it early Barrett's mucosa. Alcian blue for acidic mucins is inconsistent in this epithelium and does not reliably indicate early intestinal differentiation.