Epithelial cell processes in the development of the secondary palate in the mouse.

Ultrastructural studies of palatal shelves of Tuck A mice embryos aged 12.25-14.25 days show discontinuities of the epithelial basement membrane traversed by epithelial cell processes before the onset of midline degenerative changes.     

Chromosome secondary constrictions in different stages of development

Zusammenfassung In den Metaphasen von embryonalen und neugeborenen Amphibien, Reptilien und Säugern wurde eine grössere Anzahl von Satelliten und anderen sekundären Strukturen beobachted als in solchen von ausgewachsenen Tieren. Dies kann bedingt sein durch eine grössere Anzahl von Cistronen der rDNS, die sich aktiv in den Zellen junger Tiere befinden.

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This work was supported by the Brazilian CNPq, FAPESP and FEDIB. The authors aknowledge the technical assistance ofL. F. Napoleone.     

Epithelial cell swelling during incubation of rat small intestine in vitro

Résumé L'augmentation du fluide du tissu de l'intestin grèle incubé in vitro s'accompagne d'un accroissement du volume des cellules épithéliales.     

Regulation of mouse trophoblast giant cell nucleus development in hatched mouse blastocysts by cyclic cytidine 3',5'-monophosphate (cCMP)

The dibutyryl analog of cCMP enlarged the nuclei of trophoblast giant cells and promoted blastocyst development. The result suggests that cCMP has a trophic effect on embryonic development, specifically by altering the size of the trophoblast cell nucleus but does not enhance trophoblast cell proliferation processes.     

Regulation of mouse trophoblast giant cell nucleus development in hatched mouse blastocysts by cyclic cytidine 3′,5′-monophosphate (cCMP)

Summary The dibutyryl analog of cCMP enlarged the nuclei of trophoblast gian cells and promoted blastocyst development. The result suggests that cCMP has a trophic effect on embryonic development, specifically by altering the size of the trophoblast cell nucleus but does not enhance trophoblast cell proliferation processes.     

The relationship between cell division and cell specialization in the mouse intestinal epithelium

Zusammenfassung Der Zusammenhang zwischen der Teilung von Ursprungszellen und der Differenzierung ihrer Tochterzellen wurde anhand von Epithelzellen des Duodenums weisser Mäuser untersucht. Um den Zustand des «steady state» zu erhalten, finden die folgenden Arten von Teilung der Ursprungszellen statt: 1) zwei neue Ursprungszellen; 2) zwei differenzierte Tochterzellen; oder 3) eine neue Ursprungszelle und eine differenzierte Tochterzelle.

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I wish to particularly thank Mrs. Z.Trirogoff for her skilled technical assistance. This work was supported in part by Research Grant No. GM 14749-01, National Institutes of Health and General Research Support Funds, UCLA School of Medicine. Portions of this work were presented before the American Association of Anatomists, Anat. Rec.157, 333 (1967).     

Fluorescent mast cell in precancerous mouse skin

Résumé L'application d'un hydrocarbure cancérigène à la peau de la souris est suivie d'une mastocytose très nette qui évolue dans le tissu conjonctif. Après traitement au formaldéhyde d'une coupe gelée, quelques mastocytes prennent au microscope à fluorescence une couleur brun doré. Par essai direct et par chromatographie sur papier, on a constaté que la substance fluorescente est le dérivé-carboline de la 5-hydroxy-tryptamine.     

Molecular processes involved in B cell acute lymphoblastic leukaemia

B cell leukaemia is one of the most frequent malignancies in the paediatric population, but also affects a significant proportion of adults in developed countries. The majority of infant and paediatric cases initiate the process of leukaemogenesis during foetal development (in utero) through the formation of a chromosomal translocation or the acquisition/deletion of genetic material (hyperdiploidy or hypodiploidy, respectively). This first genetic insult is the major determinant for the prognosis and therapeutic outcome of patients. B cell leukaemia in adults displays similar molecular features as its paediatric counterpart. However, since this disease is highly represented in the infant and paediatric population, this review will focus on this demographic group and summarise the biological, clinical and epidemiological knowledge on B cell acute lymphoblastic leukaemia of four well characterised subtypes: t(4;11) MLL-AF4, t(12;21) ETV6-RUNX1, t(1;19) E2A-PBX1 and t(9;22) BCR-ABL1.     

The behavioral development of the mutant "staggerer" mouse]

The behavioural study, in particular rearing environmental conditions, of the mutant mouse staggerer has shown that such animals may live more than 90 days. (he behavioural diagnosis of this mutation has been possible from the second week of life, using specific tests. A typical "bat posture" permits one to recognize the mutant from the normal Mouse. Locomotory and feeding behaviours also present late and various qualitatige particularities.     

The effect of litter rank on the development of mouse lymph nodes

Zusammenfassung Das Gewicht der Lymphknoten von 6–7 1/2 Wochen alten C57BL- und C3H-Mäusen sank in aufeinanderfolgenden Würfen ab. Umgekehrte Verhältnisse fanden sich bei AKR-Mäusen. Verzögertes Wachstum war für die kleinen Lymphknoten der späteren Würfe bei drei und sechs Wochen alten C57BL-Tieren verantwortlich.     

Comparison of the in vitro development of mouse single blastomeres with and without the zona pellucida

Summary No difference was observed during in vitro development between mouse single blastomeres with and without the zona, pellucida, isolated from 2- and 4-cell stage eggs.     

Comparison of the in vitro development of mouse single blastomeres with and without the zona pellucida

No difference was observed during in vitro development between mouse single blastomeres with and without the zona pellucida, isolated from 2- and 4-cell stage eggs.     

Lactic dehydrogenase isoenzymes in various cell types of mouse liver

Zusammenfassung Mit einer einfachen Methode wird demonstriert, dass Lebergewebe von Mäusen in 2 Fraktionen verschiedener Menge an Bindegewebe zu trennen ist. Die an Bindegewebe reiche Fraktion zeigt Enzymaktivität in LDH 1, 2, 3, 4 und 5. Nach Entfernung des Bindegewebes wird die Aktivität der LDH 1, 2, 3 und 4 Isoenzyme des restierenden Lebergewebes reduziert.     

Effects of 5-bromodeoxyuridine on in vitro development of mouse embryos in the early somitic stage

Summary The inhibitory effect of 5-bromodeoxyuridine on the early somitic stages of mouse embryos was largely prevented in the presence of excess thymidine but only partially prevented by deoxycytidine.     

Changes in the distribution of gamma-glutamyl transferase in the organs of the mouse as a function of development]

In the Mouse, gamma-glutamyl transferase distribution changes with development in the kidney and the liver; on the contrary, its activity remains almost equal and low in other organs. In the liver, a low activity is observed in the fetus and the new-born up to the 3rd day of life; then it is no more measurable. In the kidney, the low enzyme activity of the fetus is multiplied by 10 in the 10 first days of life and by 50 in the 6 first weeks.