The effect of chloroquine upon the developing lens

Applied to the developing lens of the 14-day-old chick embryo, in organ culture conditions, chloroquine prevented the elongation of the primary lens fibres, destroyed the equatorial ones and provoked vacuolisation and/or destruction in the epithelial cells.     

The effect of chloroquine upon the developing lens

Summary Applied to the developing lens of the 14-day-old chick embryo, in organ culture conditions, chloquine prevented the elongation of the primary lens fibres, destroyed the equatorial ones and provoked vacuolisation and/or destruction in the epithelial cells.This work was supported by a grant from the office of the Chief Scientist, Ministry of Health, Israel     

A simple method for counting nuclei in the preimplantation mouse embryo

Summary An easy and rapid method of counting the number of cells in the preimplantation mouse embryo is described. The procedure increases the speed with which large numbers of embryos can be processed using a simple squash technique. Cell numbers are determined by exposing the embryos to the fluorescent DNA-binding dye, Hoechst 33258, removing the zona pellucida and simply squashing the embryo and counting the number of fluorescent nuclei. An increase in fluorescent intensity and maintenance of nuclear conformation of the squashed preparations are greatly improved by the use of the non-ionic detergent Triton X-100. Viability of dye-treated fertilized one-cell and blastocyst stage embryos is maintained at least up to day 13 of pregnancy following transfer of the embryos to the uteri of pseudopregnant recipients. Additional uses for this staining technique are discussed.Acknowledgment. Financial support was provided by NIH Grant HDD-06210 (KME) and by Basil O'Connor Starter Research Grant No. 5-379 from the March of Dimes Birth Defects Foundation (VEP). We thank Steven Halpern for help with the photography and Jon Flax for expert technical assistance.     

A simple method for counting nuclei in the preimplantation mouse embryo

An easy and rapid method of counting the number of cells in the preimplantation mouse embryo is described. The procedure increases the speed with which large numbers of embryos can be processed using a simple squash technique. Cell numbers are determined by exposing the embryos to the fluorescent DNA-binding dye, Hoechst 33258, removing the zona pellucida and simply squashing the embryo and counting the number of fluorescent nuclei. An increase in fluorescent intensity and maintenance of nuclear conformation of the squashed preparations are greatly improved by the use of the non-ionic detergent Triton X-100. Viability of dye-treated fertilized one-cell and blastocyst stage embryos is maintained at least up to day 13 of pregnancy following transfer of the embryos to the uteri of pseudopregnant recipients. Additional uses for this staining technique are discussed.     

Effects of dibutyryl cyclic AMP on cultured brain cells from chick embryos of different ages

Summary The effect of dibutyryl cyclic AMP on cultivated astroblasts from 8-, 12- and 15-day-old chick embryo brain has been studied. The results show that these cells must have reached some degree of maturation in ovo to become morphologically differentiated by the cyclic nucleotide.     

Effects of dibutyryl cyclic AMP on cultured brain cells from chick embryos of different ages.

The effect of dibutyryl cyclic AMP on cultivated astroblasts from 8-, 12- and 15-day-old chick embryo brain has been studied. The results show that these cells must have reached some degree of maturation in ovo to become morphologically differentiated by the cyclic nucleotide.     

Differentiation of the endodermal epithelium associated with the splanchnic mesoderm]

Allantoic epithelium and epithelium from different levels of the digestive tube of the guail embryo were grafted into chick embryo splanchnopleure so that these epitheliums would come into contact with the mesoderm of the developing host digestive tube at a variety of levels. Under these conditions, the allantoic epithelium develops into an epithelium corresponding to the level of the digestive tube at which it was grafted. By contrast, the presumptive fate of epithelium from the small intestine is not modified by the mesenchyme with which it becomes associated. Mesenchyme from the small intestine, on the other hand, always dictates the type of differentiation in epithelial grafts from other levels of the digestive tube.     

Identification of thromboxane B2 in guinea-pig uterine homogenates

On the basis of gas chromatographic and mass spectrometric evidence, thromboxane B2 has been identified in incubates of homogenised guinea-pig uterus.     

Identification of thromboxane B2 in guinea-pig uterine homogenates

Summary On the basis of gas chromatographic and mass spectrometric evidence, thromboxane B₂ has been identified in incubates of homogenised guinea-pig uterus.This study was supported by the M. R. C.     

A malignant tumour in the female genital tract of Pachygnatha clercki Sundevall, 1823 (Arachnida, Araneae, Tetragnathidae)]

A first case of genuine neoplasm is reported in the order Araneida. This epithelial tumor, proceeding from oviduct ends, invades uterus; malignancy is strongly supported by cell structure and extensive local behavior.     

A sperm GPI-anchored protein elicits sperm-cumulus cross-talk leading to the acrosome reaction

The acrosome reaction has long been thought to be induced by the zona pellucida. Here we report the identification and function of a novel human sperm glycosylphosphatidylinositol (GPI)-anchored membrane protein, NYD-SP8. The release of the protein during sperm-egg interaction and its binding to the cumulus, the first layer of egg investment, elicits cross-talk between the gametes and produces calcium dependant release of progesterone, which lead to the acrosome reaction. An in vivo mouse model of NYD-SP8 immunization is also established showing a reduced fertility rate. Thus, contrary to accepted dogma, our study demonstrates for the first time that, prior to reaching the zona pellucida, sperm may release a surface protein that acts on the cumulus cells leading to the acrosome reaction, which may be important for determining the outcome of fertilization. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Received 11 August 2008; received after revision 18 December 2008; accepted 22 December 2008     

Detection of human antigens on the surface of mouse cells transformed by chromosome transfer]

Mouse embryo cells, transformed in vitro by the transfer of chromosomes from HeLa human tumour cells, express a surface antigen (s) also found on HeLa cells. This antigen(s), which has been detected both by indirect immunofluoresence and by a 125I-protein A binding assay, is not an antigen(s) shared by both Human and Mouse cells.     

Wirkung von Actinomycin auf das Enzymmuster der Rattenniere während der Entwicklung

Summary Actinomycin D causes a marked increase of alkaline phosphatase activity in the zona subcorticalis of the developing rat kidney. The effect is more pronounced in female than in male animals. Acid phosphatase activity increases in males only.     

Tumor induction in mice treated with hydrocortisone and innoculated with polyoma transformed hamster cells]

Tumors have been induced in hydrocortisone treated Mice innoculated with wild-type polyoma transformed Hamster cells. The filtrate from these tumors infects Mouse embryo cells and induces the production of polyoma virus. The polyoma virus has been characterised in the infected cells with anti-polyoma capsid serum.     

Human Genome and Diseases:¶Apaf1 in developmental apoptosis and cancer: how many ways to die?

Apaf1 has been described as the core of the apoptosome. Deficiency in murine Apaf1 leads to embryonic lethality with a phenotype affecting many aspects of developmental apoptosis. In the developing brain, Apaf1 is a death regulator of the neuronal founder cells. Combined intercrosses of mouse lines mutant for members of the mitochondrial death pathway are providing us with some clues about the relative regulation existing among neuronal cell populations. Apaf1-deficient embryos display an interesting phenotype in the inner ear and in limb development, which involves different caspase-dependent and -independent pathways. Moreover, APAF1 is mutated in human melanomas, and its depletion contributes to malignant transformation in a mouse model of cancer. This review has a double aim: the analysis of the alternatives taken by the embryo to bring into the suicidal program different cells at different stages, and the relevance of APAF1 in the onset and progression of cancer. Received 5 March 2001; received after revision 19 April 2001; accepted 4 May 2001     

Scanning and transmission electron microscopic evidence of epithelial phagocytosis of spermatozoa in the terminal region of the vas deferens of the cat

Scanning and transmission electron microscopic observations have been made in the terminal region of the vas deferens of the cat, with emphasis on the occurrence of spermiophagy. The present study has revealed that epithelial cells as well as luminal macrophages are extensively and actively involved in phagocytosis of spermatozoa. The mechanism of the spermiophagy is discussed, in relation to a possible role of the epithelial cells, as one function of the vas deferens.     

Redundant regulation of localization and protein stability of DmPar3

Apical–basal polarity is an important characteristic of epithelia and Drosophila neural stem cells. The conserved Par complex, which consists of the atypical protein kinase C and the scaffold proteins Baz and Par6, is a key player in the establishment of apical–basal cell polarity. Membrane recruitment of Baz has been reported to be accomplished by several mechanisms, which might function in redundancy, to ensure the correct localization of the complex. However, none of the described interactions was sufficient to displace the protein from the apical junctions. Here, we dissected the role of the oligomerization domain and the lipid-binding motif of Baz in vivo in the Drosophila embryo. We found that these domains function in redundancy to ensure the apical junctional localization of Baz: inactivation of only one domain is not sufficient to disrupt the function of Baz during apical–basal polarization of epithelial cells and neural stem cells. In contrast, mutation of both domains results in a strongly impaired protein stability and a phenotype characterized by embryonic lethality and an impaired apical–basal polarity in the embryonic epithelium and neural stem cells, resembling a baz-loss of function allele. Strikingly, the binding of Baz to the transmembrane proteins E-Cadherin, Echinoid, and Starry Night was not affected in this mutant protein. Our findings reveal a redundant function of the oligomerization and the lipid-binding domain, which is required for protein stability, correct subcellular localization, and apical–basal cell polarization.     

Scanning and transmission electron microscopic evidence of epithelial phagocytosis of spermatozoa in the terminal region of the vas deferens of the cat

Summary Scanning and transmission electron microscopic observations have been made in the terminal region of the vas deferens of the cat, with emphasis on the occurrence of spermiophagy. The present study has revealed that epithelial cells as well as luminal macrophages are extensively and actively involved in phagocytosis of spermatozoa. The mechanism of the spermiophagy is discussed, in relation to a possible role of the epithelial cells, as one function of the vas deferens.