Leo Loeb

The experimental production of the maternal part of the placenta in the rabbit.

In a former communication 2 I stated that I had been able to produce at will, decidual tumors in the uterus of the guinea-pig by making deep incisions into the wall of the uterus, at certain periods of the sexual cycle. The nodules thus produced belong to that class of formations which I designated as “transitory tumors.” Since then, further investigations 3 have demonstrated that these deciduomata are produced under the influence of an internal secretion of the ovaries. There are indications that it is the corpus luteum which produces this internal secretion. If such a “preparing substance” has been secreted by the ovaries, indifferent stimuli are sufficient to call forth the development of the deciduomata. In the guinea-pig the new formations show a structure identical with that of the decidua. Large cells of connective tissue origin show an epithelial arrangement. The nuclei of many cells are hypertrophic, the cytoplasm is, on the whole, solid, and stains well with eosin. The decidual tissue of the placenta of the rabbit differs in some important respects from that of the guinea-pig, if we compare the placentas at the corresponding stages of development. In the rabbit the decidual cells are quite vacuolar and the blood vessels show an interesting change. At a very early period the endothelial lining becomes transformed into syncytial and plasmodial masses. It was of interest to determine whether the deciduae produced experimentally in the guinea-pig and in the rabbit differed in the same way as the normal deciduae in these two species. The following experiments were, therefore, carried out : 1 In four female rabbits which had been kept separated from males for some time previous to the operation and which were not pregnant, no deciduomata were formed after the usual incisions into the uterus had been made. We found only edematous mucosa on microscopic examination,

Zur Analyse der Entstehungsbedingungen der Thromben und Lebernekrosen nach intravenöser Injektion von Äther

die fnnktionelle Anpassung der Ge~Bwand. Ztlbl. f. allg. Path. usw, 1908, Bd. 19, S. 936. --3. R ii s s 1 e, Uber Hypertrophie und Organkorrelation. ~finch. med. Wschr. 1908, Nr. 8. 4. S c h e e 1, GefitBmessungen und Arteriosklerose. Vireh. Arch. 1908, Bd. 191, S. 135. 5. S c h i e 1 e W i e g a n d t , Uber Wanddicke und Umfang der Arterien des menschliehen K6rpers. Virch. Arch. 1880, Bd. 82, S. 27. 6. S u t e r , Uber das Verhalten des Aortenumfangs unter physiologischen und pathologisehen Bedingungen. Arch. f. exper. Path. u. Ther. 1897, Bd. 39, S. 289. 7. T h o r e 1, Pathologie der Kreislauforgane. Lubarsch-Ostertag, Ergebn. d. allg. Path. u. path. Anat. 1903, I, S. 936, 9. Jhrg. ~ 8. T h o r e 1, Pathologie der Kreislauiorgane. Lubarsch-Ostertag, Ergebn. d. allg. Path. u. path. Anat. 1907, II, S. 458, 11. Jhrg.

Über den Einfluß des Lichtes auf die Färbung und die Entwicklung von Eiern von Asterias in Lösungen verschiedener Farbstoffe

Dureh die Untersuchungen einer Reihe yon Forsehern (RAAB, V. TAPPEINER nnd JODLBAUER, LEDOUX-LEBARD, STRAUB, EDLEFSEN and andre 1)) wurde festgestellt, dab fiuoreseierende Stoffe, wie z. B. Eosin, au f Zellen und ffewisse Fe rmente im Lichte eine viel sch~idliehere Wi rkung ausUben als im Dunkeln. Im folgenden sollen einige Befunde mitgeteilt werden, die an Zellen (Seesterneiern) erhoben warden, welehe in Misehungen ver-