Differential, multihormonal regulation of the mouse major urinary protein gene family in the liver.

The hormonal requirements for the regulation of the major urinary protein (MUP) mRNA levels in mouse liver have been examined. Previous experiments have shown that administration of testosterone to female or castrated male mice increases MUP mRNA levels approximately fivefold to normal male levels. We have found that thyroxine and the peptide hormone, growth hormone, each had a pronounced effect on MUP mRNA levels. MUP mRNA was reduced 150-fold in growth-hormone-deficient mutant mice (little). The administration of growth hormone and thyroxine induced MUP mRNA approximately 150-fold, and when administered together, they induced MUP mRNA approximately 1,000-fold. testosterone administration. When administered separately to these mice, growth hormone and thyroxine induced with MUP mRNA approximately 150-fold, and when administered together, they induced MUP mRNA approximately 1,000-fold. Testicular feminized mice, which lack a functional major testosterone receptor protein, can also be induced to male levels by treatment with both growth hormone and thyroxine. In addition, we present evidence which indicates that growth hormone, thyroxine, and testosterone differentially regulate the levels of distinct MUP mRNA species.     

Congenital defects of the upper lateral incisors (ULI) and the morphology of other teeth in man

A sample of 192 male propositi with at least one ULI either missing or reduced has been compared with 197 male controls in terms of the morphology of the other teeth. Every class of propositi exhibits modifications in the following characters: Significant differences between propositi and controls were found for molar cusp number and groove pattern, particularly in the lower first molar and in propositi with reduced ULI. Significant differences between propositi and controls were also found with respect to caniniform pattern of the lower first premolar. The Carabelli's cusp is rarer in propositi. A hypothesis to account for these observations is proposed.     

Augmentation of erythroid burst formation by the addition of thymocytes and other myelo-lymphoid cells

Bone marrow from barrier-sustained specific pathogen-free (SPF) CBA and C57BL/6 mice gave relatively low numbers of BFU-E colonies in methylcellulose culture, as compared to conventional mice. Addition of thymocytes to the marrow cultures increased the yield of BFU-E colonies more than fourfold in SPF mice but only 1.5-fold in conventional mice. Colony size was also increased. Increased yield of BFU-E colonies was also obtained by co-culture of bone marrow with lymph node cells or with bone marrow or spleen cells from 900R whole-body-irradiated mice. The effect appeared to be cellular rather than humoral. It was not reproduced by conditioned medium from thymus or pokeweed mitogen stimulated spleen cells. The helper effect of thymus cells was eliminated or reduced by freezing and thawing, or by 48 hours of incubation after irradiation. Treatment of bone marrow cells in vitro with anti-theta serum and complement did not decrease the number of BFU-E colonies. The putative helper cells appear not to be T cells, were non-adherent to the plastic culture dish, and were cortisone resistant and radioresistant. The low BFU-E colony yield from SPF mouse marrow is presumed to be largely the result of deficiency of these non-T helper cells in SPF bone marrow, rather than of BFU-E progenitor cells.     

Differential Giemsa staining of heterochromatic B-chromosomes in Myrmeleotettix maculatus (Thunb.) (Orthoptera: Acrididae)

A modified Giemsa staining technique has been used to investigate the karyotype of the grasshopper Myrmeleotettix maculatus, since this stain appears to be diagnostic for certain repetitive DNAs. The centromeric regions are densely heterochromatic, and further heterochromatic bands occur on the X-chromosome and on both arms of the B-chromosome. The significance of these results is discussed in relation to centromeric structure and B-chromosome structure in this insect, and a possible origin of the B-chromosome is suggested.     

Lack of Sequence Homology Between the 70S RNA of Various RNA Tumor Viruses and the DNA of Simian Virus 40 or Polyoma Virus

No significant hybridization was detected of DNA from simian virus 40 or polyoma virus, and of 70S RNA from avian myeloblastosis virus, murine leukemia virus (Rauscher), murine sarcoma virus (Kirsten), RD-114B, simian sarcoma virus-1, or Mason-Pfizer virus.     

Ultrastructure de l'épithélium tégumentaire de Glossiphonia complanata (L.) (Hirudinée): cellules épithéliales et organes sensoriels de Bayer

Résumé Le tégument de Glossiphonia complanata comprend, outre les cellules épithéliales banales, de nombreux organes particuliers ou organes de Bayer, regroupés essentiellement sur la face dorsale de l'animal. Ils sont formés par une cellule apicale saillante enchassée dans une cellule musculaire en anneau.L'ensemble de ces formations est étudié du point de vue ultrastructural. Des cellules épithéliales partent des fibres nerveuses afférentes, sans doute vecteur des perceptions de stimuli mécaniques de pression au niveau du tégument; la réponse se faisant sans doute par la contraction de la cellule basale de chaque organe de Bayer, innervée par des fibres nerveuses efférentes, entrainant la saillie de la cellule apicale. Le hérissement de ces nombreuses papilles du tégument dorsal pourrait être un signal perçu par le partenaire sexuel, chez cette Hirudinée à fécondation hypodermique.

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Ultrastructure of the integumentary epithelium of Glossiphonia complanata (L.) (hirudinea): Epithelial cells and sensory organs of bayer

Summary The integument of Glossiphonia complanata, built up by epithelial cells, contains numerous particular organs (Bayer organs), mainly on the dorsal side of the animal. They consist of a protuberant apical cell, which is surrounded by a ring-shaped muscle cell. All the integumentary formations are studied from an ultrastructural point of view. From the epithelial cells issue afferent nerve fibres, considered as vectors of the perception of mechanical stimuli of pressure at the level of the integument; the response no doubt operating by the contraction of the basal muscle cell of each Bayer organ, innervated by efferent nerve fibres, bringing forth the protrusion of the apical cell. The erection of these numerous papillae of the dorsal integument might be a signal perceived by the sexual partner, fecundation occurring in this group of leeches under the integument.

     

Heparin augments osteoclast resorption-stimulating activity in serum

Increased numbers of mast cells are commonly seen at sites of increased bone resorption and in osteoporosis. Long-term administration of heparin, a major component of mast cell granules, causes osteoporosis. We therefore tested the effect of heparin on bone resorption by osteoclasts disaggregated from neonatal rat long bones. We found that, in the absence of serum, heparin was without effect on osteoclast function. However, in the presence of newborn calf serum, rat serum, or bovine platelet-poor plasma-derived serum, heparin, in the range 25-100 micrograms/ml, induced an increase in osteoclastic bone resorption. Heparin appeared to act through binding and enhancement of an osteoclast resorption-stimulating activity (ORSA) present in serum. A number of known factors that show an affinity for heparin, including transforming growth factor-beta, platelet-derived growth factors, insulin-like growth factors I or II, acidic or basic fibroblast growth factors, fibronectin, or laminin, could not substitute for ORSA, suggesting that the activity may represent a novel heparin-binding factor. The ability of glycosaminoglycans (GAGs) and related molecules to enhance resorption was dependent on the degree of sulfation and on their size: The high molecular weight GAG heparan sulfate and polysaccharides fucoidan or dextran sulfate showed a similar effect, while low molecular weight heparin, chondroitin-2-sulfate, chondroitin-4-sulfate, and chondroitin-6-sulfate were without effect. We propose that mast cells or heparin therapy increases bone resorption through augmentation of the activity of a factor involved in the local and systemic regulation of osteoclastic bone resorption.