Epithelial and mesenchymal cell interactions with extracellular matrix material in vitro

Epidermal organogenesis (thyroid gland, salivary gland, feather, hair, skin, thymus gland, tooth, etc.) generally follows a basic rule; epithelium exhibits well-documented interdependence with adjacent mesenchyme for a specific path of development (Grobstein, 1967, for review). Koch (1967) demonstrated in rodent embryos that isolates of incisor epithelial and mesenchymal tissue, separated by a millipore filter, continued to develop. When homotypic tissues were placed in juxtaposition to the filter, no evidence of continued differentiation was observed.

Isolated cervical loop tissues of tooth germs from mammalian embryos have been shown to develop into an entire tooth in vitro (Slavkin & Bavetta, 1968 a; Kollar & Baird, 1969). Our laboratory recently reported that isolated tissue preparations (Slavkin & Bavetta, 1968 a) or cell suspensions (Slavkin, Beierle & Bavetta, 1968) of epithelial and mesenchymal cells from the embryonic cervical loop, in recombination on the chick chorioallantoic membrane (CAM), reconstituted and developed into a tooth germ.

Infant vocalizations and their relationship to mature intelligence

Correlations between infant development tests and later intelligence have been found previously to be very low. Through cluster analysis, six clusters of items were extracted from Bayley's California First Year Mental Scale. One item cluster composed principally of vocalizations did significantly correlate with girls' later intelligence, increasingly so with age, and more highly with verbal than performance scores.

Craniometric Memoirs: No. II. The Human and Comparative Anatomy of Cameron's Cranio-facial Axis

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The Structure of the Blastoderm, and the Continuity of the Cell-Elements during the Early Stages of Development

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A Specimen showing Complete Remains of the Left Superior Vena Cava; with a Description of a Venule, which Represents the "Lost" Extra-pericardiac Portion of the Left Duct of Cuvier

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The Cranial Attachment of the Internal Lateral Ligament of the Lower Jaw: with an Investigation into the Fibrogenesis of this Structure

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Further Researches on the Rods and Cones of Vertebrate Retinae

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The Lamina Terminalis and its Relation to the Fornix System

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The Development of the Auditory Nerve in Vertebrates

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The Fascia of the Perineum and Pelvis of the Female, with Special Reference to the Mechanical Supports of the Pelvic Viscera

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The Fascia of the Pelvis

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A Brain with Complete Absence of the Corpus Callosum

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The Histogenesis of Nerve Fibres: A Cytological Study of the Embryonic Cell-Nucleus

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