Prenatal morphogenesis of mammary glands in mouse and rabbit.

Our understanding of prenatal morphogenesis of mammary glands has recently greatly advanced. This review focuses on morphogenesis proper, as well as cellular processes and tissue interactions involved in the progression of the embryonic mammary gland through sequential morphogenic stages in both the mouse and rabbit embryo. We provide a synthesis of both historical and more recent studies of embryonic mammary gland development, as well as arguments to revise old concepts about mechanisms of mammary line and rudiment formation.

Harmful effects of cadmium on olfactory system in mice.

The inhalation of certain metals can result in olfactory epithelial injury, an altered sense of smell, and direct delivery of the metal from the olfactory epithelium to the olfactory bulbs and other parts of the central nervous system. The purpose of this study was to examine whether mice given an intranasal instillation of cadmium would develop altered olfactory function and to assess whether cadmium may be transported directly from the olfactory epithelium to the central nervous system. To evaluate cadmium's ability to induce anosmia and on the basis of olfactory epithelium sensitivity to metals, the aim of this study was first to study cadmium effects on the olfactory function and secondly to check whether cadmium may be transported from the nasal area to the central nervous system.

Culture of neural cells on polymers coated surfaces for biosensor applications.

We focused our study on the olfactory cells growth on biocompatible polymer films electrodeposited on a silicon microsystem. Several substrates such as polyethyleneimine (PEI), polypropyleneimine (PPI), and polypyrrole (PPy), acting as potentially good candidates for cell culture, were tested in order to allow cells to adhere and proliferate. During their growth, the evolution of their morphology was monitored using both confocal microscope and immunohistochemistry, leading to the conclusion of a normal development.

Adhesion and proliferation of cells on new polymers modified biomaterials.

Up to today, several techniques have been used to maintain cells in culture for studying many aspects of cell biology and physiology. More often, cell culture is dependent on proper anchorage of cells to the growth surface. Poly-l-lysine is commonly used as adhesive molecule.

Accumulation of Ym1/2 protein in the mouse olfactory epithelium during regeneration and aging.

A unique feature of the olfactory system is its efficiency to produce new neurons in the adult. Thus, destruction of the olfactory receptor neurons (ORNs) using chemical (intranasal perfusion with ZnSO4) or surgical (axotomy or bulbectomy) methods, leads to an enhanced rate of proliferation of their progenitors and to complete ORNs regeneration. The aim of our study was to identify new factors implied in this regenerative process.

Recovery following peripheral destruction of olfactory neurons in young and adult mice.

Olfactory neurons (ON) which are located in the olfactory epithelium are responsible of odorous molecule detection. A unique feature of these cells is their continuous replacement throughout life due to the proliferation and differentiation of local neural precursors, the basal cells. Thus, experimental destruction of all ON induces a stimulation of basal cell division followed by tissue regeneration.

Cell cycle regulation during mouse olfactory neurogenesis.

The development of the nervous system requires a strict control of cell cycle entry and withdrawal. The olfactory epithelium (OE) is noticeable by its ability to yield new neurons not only during development but also continuously during adulthood. The aim of our study was to investigate, by biochemical and immunohistochemical methods, which cell cycle regulators are involved in the control of neuron production during OE development and maturity.

Region-specific expression of cell cycle inhibitors in the adult brain.

In the adult brain, neural proliferation is almost absent and neurons are generally not renewed. By contrast, in the olfactory organ, olfactory neurons are produced continuously throughout life. To investigate whether specific cell cycle inhibitors are involved in the control of neural quiescence in adulthood, we compared their expression either in different regions of the adult brain weakly or non neurogenic or, for comparison, in the olfactory mucosa.

Functional alterations in the olfactory bulb of the staggerer mutant mouse.

Putative alterations of the functional activity in the staggerer mutant mouse olfactory bulb neuronal network have been studied by recording odor induced evoked field potentials (EFP) in the mitral cells layer. In standard conditions, the main feature observed in mutants was a significant increase in latency preceding the functional response of the mitral cells to the odorant. In these animals, all parameters of the average EFP were widely modified when compared with those recorded in wild mice.

Detection of alpha-L fucose containing carbohydrates in mouse immature olfactory neurons.

The cellular location of alpha-L fucose was studied in mice olfactory epithelium (OE) using the Ulex europaeus agglutinin-I (UEA-I) and Tetragonolobus purpureas agglutinin (TPA). In adult mice, UEA-I and TPA revealed a layer of cells that mostly correspond to immature olfactory neurons. Moreover, autoradiographic studies after 3H-T incorporation showed that UEA-I cell labelling occurred during the week following the division of neural cell precursors.

Structural and immunohistological modifications in olfactory bulb of the staggerer mutant mouse.

In the present study, we describe the structural and cytological changes observed in staggerer mutant olfactory bulbs, as compared to normal mice. On the basis of photonic and ultrastructural observations we tried to define the alterations induced by the mutation: i.e.

Lesbianism in female and coed correctional institutions.

Abstract Questionnaire responses from 13- to 17-year-old girls in four all-female and three coed institutions were used to determine rates and causes of institutional homosexuality. Rates were as high in coed as in single-sexed institutions. The overall rates of homosexuality for all seven institutions were 14% for "going with or being married" to another girl, 10% for passionately kissing, 10% for writing love letters, and 7% for having sex, beyond hugging and kissing, with another girl.

Differential EGF action on nuclear protooncogenes in human endometrial carcinoma RL95-2 cells.

Our aim was to analyze EGF action on nuclear protooncogenes in RL95-2 since it has not been documented so far. Synchronization and partial' growth arrest were obtained by maintaining cells for 15 hours in L-methionine-free medium. After this depletion, EGF transiently increased fos and jun mRNAs: the expression peaked at 45 minutes for c-fos (5.

Ultrastructural changes in guinea pig endometrial cells during the estrous cycle.

In the guinea pig, the estrous cycle is characterized by a constant measurable level of plasma progesterone with two peaks: the first one associated with the peak of plasma estradiol-17 beta occurring at proestrus and the second, during diestrus, more pronounced at the time at which the level of estradiol-17 beta is undetectable. The progesterone receptor content is the highest on day 1 and the lowest on day 10 of the estrous cycle, which lasts 16.3 +/- 1.

Expression of c-fos and c-myc genes in uterus and nonreproductive organs during the implantation period in the rat.

The c-fos and c-myc mRNA levels were investigated in the uterus and nonreproductive organs of rats during the implantation period (from day 5 to 7 of pregnancy). They were determined by densitometric analysis of slot blots and the mean values (n = 4) at a defined age of pregnancy were compared with those observed in nonpregnant control rats (NP group). No significant variations of c-fos level were observed in the liver and brain of pregnant rats.

Additive effect of oestradiol-17 beta and serum on synthesis of deoxyribonucleic acid in guinea-pig endometrial cells in culture.

Normal guinea-pig endometrial cells, grown in primary culture, were made quiescent by serum depletion. Quiescent cells cultured in the control medium (containing 1% fetal calf serum treated with dextran-coated charcoal, DCC-FCS) showed a steady and weak rate of [3H]thymidine incorporation, but the addition of 15% fetal calf serum (FCS) or 10% DCC-FCS to the control medium induced a significant increase of DNA synthesis, demonstrating the responsiveness of the quiescent cells to stimulation. A lower but significant increase in [3H]thymidine incorporation was elicited by epidermal growth factor (EGF, 100 ng/ml) or insulin (10 micrograms/ml) added to the basal medium.

Proliferation of guinea-pig uterine epithelial cells in serum-free culture conditions: effect of 17 beta-estradiol, epidermal growth factor and insulin.

The effects of 17 beta-estradiol (E2), epidermal growth factor (EGF) and insulin, alone or in association on guinea-pig uterine epithelial cell proliferation were examined in serum-free culture conditions. Primary cultures of epithelial cells were made quiescent by serum depletion, then incubated in a chemically defined medium. In this medium, insulin increased DNA synthesis but not in a dose-dependent manner for concentrations ranging from 0.

Establishment of endometrial glandular epithelial cell subculture in a serum-free, hormonally defined medium, on a basement membrane matrix.

Epithelial glands were isolated from guinea-pig endometrium. In order to reduce the requirement for a serum supplement and the contamination by non epithelial cells in primary culture, various coatings of the culture dishes were tested using serum-free Ham's F12 containing defined chemicals including 17 beta-estradiol. While epithelial glands seeded on culture dishes coated with Matrigel, a basement membrane matrix-failed to spread, they formed on poly-D-lysine plus serum-coated dishes, a subconfluent monolayer (5-7 days) enriched in cytokeratin-immunostained cells (78%).

Specific effect of oestrone sulphate on protein synthesis and secretion by cultured epithelial cells from guinea-pig endometrium.

Patterns of induced protein synthesis and secretion in guinea-pig endometrial epithelial cell cultures in response to oestrone sulphate alone and oestrone sulphate plus progesterone were investigated. Epithelial cells were cultured for 3 days in growth medium, then washed three times in a steroid-free medium. For each experiment, anticytokeratin immunostaining was used to discriminate the epithelial cells from the stromal cells.

Ultrastructural changes induced by oestradiol-17 beta, progesterone and oestrone-3-sulphate in guinea-pig endometrial glandular cells grown in primary culture.

The effects of oestradiol-17 beta, progesterone and oestrone-3-sulphate were studied in primary cultures of guinea-pig endometrial glandular epithelial cells. Comparative ultrastructural studies were performed by means of transmission electron microscopy on cells grown either without hormones or with oestradiol-17 beta (2 nmol/l), oestradiol-17 beta (2 nmol/l) plus progesterone (50 nmol/l), or oestrone sulphate (0.1 mumol/l).

Effect of progesterone on protein synthesis and secretion by cultured epithelial cells from guinea-pig endometrium.

The pattern of proteins synthesized and secreted in response to progesterone by guinea-pig endometrial epithelial cell cultured with estradiol-17 beta was investigated. Glandular epithelial cells were maintained in culture for 3 days on growth medium, then washed three times with a steroid-free medium. After this period, 2 x 10(-8) M estradiol-17 beta or 2 x 10(-8) M estradiol-17 beta plus 5 x 10(-7) M progesterone were added to the medium for 48 h.

[Action of estradiol-17 beta, estrone sulfate and progesterone on the growth and differentiation of endometrial epithelial cells of the guinea pig in primary culture].

Endometrial guinea-pig glandular epithelial cells grown in primary culture incorporated [3H] thymidine. After three washings with a steroid-free medium, they were made quiescent and arrested in the G0/G1 phase. However, they remained hormone-responsive and resumed the cellular cycle after stimulation by 10(-6) M oestrone sulphate but not by oestradiol-17 beta.

Oestrone sulphate metabolism in normal human endometrium grown in organ culture.

Samples of human endometrium were maintained in organ culture for 6 days on growth medium. On Day 6, ultrastructural studies were performed on endometrial explants, demonstrating that human endometrium grown in organ culture preserved its normal structure. The effect of oestrone sulphate was studied on the endometrium explants.

Compared effects of oestrogens and oestrone sulphate on the epithelial cell surface of guinea-pig endometrium (in vivo and in vitro studies).

The comparative effect of oestradiol-17 beta, oestrone and oestrone-3-sulphate was examined on guinea-pig endometrium in primary culture. A parallel study was conducted in vivo to appreciate hormonal effects on the uterine luminal surface of ovariectomized guinea-pigs. Scanning electron microscopy studies showed that uterine epithelial cells were responsive to physiological concentrations of E2, E1 and E1S.

Culture of epithelial and stromal cells of guinea-pig endometrium and the effect of oestradiol-17 beta on the epithelial cells.

Epithelial and stromal cells of guinea-pig endometrium were separated by enzymic digestion, isolated by successive centrifugation, and maintained in culture as pure cell types for 5 days on growth medium. On Day 5, ultrastructural studies were performed on the two cell types, demonstrating that epithelial cells can grow as a monolayer composed of cohesive groups of polygonal cells (1.3 X 10(5) cells/cm2), while stromal cells were mostly fibroblastic.