Organ culture of suckling rat intestine: Comparative study of various hormones on brush border enzymes

Summary Jejunal mucosa of 6 d-old rats were cultured for 24 and 48 h in the presence of thyroxine, insulin, pentagastrin, glucagon, epidermal growth factor (EGF) or dibutyryl-A-3:5-MP cyclic with or without dexamethasone (DX). The enzymes were assayed on the purified brush borders. The various agents added alone to the basic culture medium had no effect with the exception of DX on the levels of enzyme activities. Dexamethasone alone induced sucrase, stimulated maltase, and protected other brush border enzyme activities (aminopeptidase, lactase, and alkaline phosphatase). When added to DX-supplemented medium, only the following factors modified the levels of enzymatic activities observed with DX alone. Insulin (10⁻⁶ M) increased maltase, alkaline phosphatase, and lactase activity to a greater extent than DX at 24 h culture, the effect being maintained at 48 h on alkaline phosphatase only. At 48 h culture, both EGF (10⁻⁸ M) and dbcAMP (10⁻³ M) decreased DX-induced sucrase activity. The latter agent also depressed DX-stimulated aminopeptidase activity. This work was supported by the Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, and a grant 79.7.1243 from the Délégation Générale a la Recherche Scientifique et Technique. P. M. S. is a recipient of a grant from Fondation de la Recherche Médicale (France).     

A brief history of genome research and bioinformatics in France

The development of in silico genomics has progressed slowly in France for a number of political reasons. Two administrative organizations, the Groupement de Recherche sur les Génomes (GREG) and the Groupement de Recherche 1029 (GDR 1029) of the Centre National de la Recherche Scientifique (CNRS) have been established. These organizations have created the dynamics that hopefully will place France (which coordinated consortia that completed several of the first large microbial genomes) among the developed nations that support Large-Scale Biology.     

Decontamination of bacterial infection of monolayer cultures with a specific bacteriophage

Summary A few cell lines and primary monolayer cultures were accidentally infected by bacteria. These cultures were successfully decontaminated by means of the specific bacteriophage virus after quick identification of the responsible bacteria. This method presents a practical interest for preservation of valuable cultures. This work is supported by the Institut National de la Sante et de la Recherche Medicale (France) and the Fondation pour la Recherche Medicale (France).     

Erythroid precursors cultured from adult mice are sensitive to H2O2 toxicity

Summary The growth of late erythroid precursors (CFU-Es) from adult bone marrow is inhibited when Iscove's modified Dulbecco's medium supplied in liquid form is used. Catalase and other H₂O₂ destroying compounds restore the capacity of culture medium to support colony development. However early precursors from adult bone marrow and fetal liver CFU-Es were resistant to H₂O₂. This work was supported by grants from the Centre National de la Recherche Scientifique, the Institut National de la Santé et de la Recherche Médicale and the Fédération Nationale des Centres de Lutte contre le Cancer.     

Skin color and climate in Central Africa: A comparison of three populations

In order to test the hypothesis that in Central Africa variation in melanin concentration in the human skin largely results from adaptation to ultraviolet radiation, skin reflectance of the inner surface of the arm was measured at 685 nm in three samples: a sample of 415 Sara, who have a long history of habitation in the very sunny savanna of Chad; a sample of 278 Oto, a Konda caste that migrated to the equatorial forest of Zaire less than two millennia ago;and a sample of 122 Twa, a Konda caste that has been in the equatorial forest longer than the Oto. The predicted Sara-Oto-Twa sequence was confirmed and is at least partly genetically based.The study presented here is a part of an International Biological Programme/Human Adaptability Program project, which has been supported by the French and Belgian International Biological Programme committees, by Recherche Coopérative sur Programme 117 of Centre National de la Recherche Scientifique, in the Chad by Institut National Tchadien pour les Sciences Humaines, and in Zaire by Office National pour la Recherche et le Développement and Institut pour Recherche Scientifique au Congo.     

Establishment of a continuous cell line from fibrotic schistosomal granulomas in mice livers

Summary A continuous murine cell line (GRX) was obtained from fibrotic granulomas induced in C3H/HeN mice liver by experimental infection withSchistosoma mansoni. This anchorage-dependent line produces composite connective tissue/extracellular matrix, displays morphological characteristics of myofibroblasts, and can, under appropriate conditions, accumulate fat droplets. GRX cells produce viral particles of retrovirus type. We consider GRX cell line to be representative of liver connective tissue cells, responsible for fibroplasia in liver fibrotic and granulomatous reactions. This research was supported by Centre National de la Recherche Scientifique, France; Financiadora de Estudos e Projetos (FINEP), Brasil; and Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), Brasil.     

Regulation of vascular development by fibroblast growth factors

Fibroblast growth factors (FGFs) are potent stimulators of angiogenesis in vitro and in vivo. However, the precise role of FGFs and vascular development in normal and pathological tissue has long remained ill defined. Recently, substantial progress has been made toward a better understanding of their role. Genetic studies in mice or in culture systems indicate a role for FGFs in vessel assembly and sprouting. FGFs also stimulate blood vessel branching and lymphangiogenesis. The molecular mechanisms by which FGFs mediate angiogenesis are also better understood. Finally, the FGF/FGF-receptor system has become a focus for the development of novel therapeutic strategies for the treatment of angiogenesis-related diseases such as tissue ischemia.Work described herein from our laboratory was supported by grants from the Ligue Nationale contre le Cancer, the Association de la Recherche sur le Cancer, Rétina France, the Institut National de la Santé et de la Recherche Médicale (INSERM), and the Ministère de la Recherche     

In vitro cytodifferentiation of perinatal rat islet cells within a tridimensional matrix of collagen

Summary Cell suspensions prepared by collagenase digestion of pancreases obtained from rat fetuses (21.5 d old) and newborns (2.5 d old) were mixed with a collagen solution and inoculated on a collagen base layer. At the onset of the culture, most acinar cells became necrotic, whereas other epithelial cells proliferated. Most of the cell clusters arranged themselves into simple polarozed structures composed of epithelial cells forming hollow spheres, and from these budded neoformed endocrine islets. Scarce fibroblasts were located close to these structures. Immunocytochemical localization of insulin and glucagon, as well as ultrastructural characteristics of the cell types revealed an intrainsular distribution similar to the in vivo localization. Tridimensional matrix of collagen offers, to perinatal pancreatic cells in culture, an environment close to the in vivo conditions: cells reorganize themselves in tissuelike structures and cell interactions concerned in the cytodifferentiation of pancreatic islets occur. This system allows for the study of undifferentiated epithelial cells—the presumed stem cells—differentiating and differentiated endocrine cells in the same preparation. B.A. is supported by a doctoral scholarship from the Institut pour l'Encouragement de la Recherche Scientifique dans l'Industrie et l'Agriculture, Brussels. This work was supported by grants from the Fonds National de la Recherche Scientifique, Brussels, and from Petrofina S.A., Brussels.     

2-Aminopurine induced mutations in T4 bacteriophage

Summary Treatment of E. coli B bacteria by the base analogue 2-aminopurine, before infection with T4 phages, induces mutations of the transition type into the virus. Treatment of the phage-bacterium complex, only during the first four minutes of the latent period i.e. at a moment where no phage DNA is synthetized, is also mutagenic. The kinetics of acquisition and loss by treated bacteria of mutagenicity and the action of various metabolic inhibitors show that the base analogue is stored into the bacterial or the phage messenger RNA from which it is reused to be incorporated into the phage DNA.This investigation was supported by the Centre National de la Recherche Scientifique (L. A. No 86 et 136), l'Institut Pasteur, la Délégation Générale à la Recherche Scientifique and la Fondation pour la Recherche Medicale.     

Effect of sodium butyrate on the hepatoma cell cycle: Possible use for cell synchronization

Summary Exposure of HTC cells to sodium butyrate caused inhibition of growth. The site of growth inhibition was studied by time-lapse cinematography and [³H]thymidine incorporation studies. Evidence is presented that sodiunm butyrate affected the cell cycle at a specific point immediately after mitosis. Inasmuch as it does not modify the interphase duration after its removal, butyrate may be used for HTC synchronization. This work was supported by l'Institut Nationale de la Santé et de la Recherche Médicale and la Centre Nationale de la Recherche Scientifique (L. T. and J. K.).     

The role of Nod signal structures in the determination of host specificity in the Rhizobium-legume symbiosis

During the past five years the structure of nodulation signals from more than a dozen different Rhizobium species has been elucidated. In addition, the role of numerous nod genes in the biosynthesis of the lipooligosaccharides has been identified. This review discusses how Nod signal structure is determined by the specificity of the various biosynthetic steps and how this influences variation in host specificity. Until recently, it appeared that the decorations of a common lipochitooligosaccharide core determine the host-specific recognition of the signals, possibly via specific receptors in the host plant cell. A number of recent publications, however, suggest that beyond the interaction of Nod signals with a putative receptor, certain structural features of Nod factors are involved in controlling the concentration of the signals during their uptake by the root tissue.The authors are with the Institut des Sciences Végétales, Centre National de la Recherche Scientifique, Avenue de la Terrasse, F-91198 Gif-sur-Yvette, France; A. Kondorosi is also with the Institute of Genetics, Biological Research Center, Hungarian Academy of Sciences P.O Box 521, H-6701 Szeged, Hungary.     

Established cell lines of mouse marrow adherent cells producing differentiation factor(s) for the granulocyte-macrophage lineage

Summary Two continuous cell lines derived from long-term cultures of AKR mouse bone marrow adherent cells were isolated. These cell lines release colony stimulating activity (CSA), a factor that induces in vitro differentiation of granulocyte-macrophage progenitor cells. The colony forming cells and cluster forming cells in mouse marrow responsive to CSA from cell line conditioned medium were compared with those responsive to CSA from mouse lung conditioned medium (MLCM). Colony forming cells were characterized by analysis of their density distribution after equilibrium centrifugation in density gradient. Cluster forming cells were characterized by analyzing the progeny of individual clusters after transfer to fresh semisolid culture medium containing MLCM. The results obtained indicate that the CSA from cell line conditioned medium closely compares with the CSA from MLCM in terms of the populations of colony and cluster forming cells stimulated. This work was supported by a research grant from the Institut National de la Santé et de la Recherche Médicale (CRL 802620), Paris, France.     

Differences and similarities of industrial and institutional promotions

The Délégation à la Recherche Clinique d'Ile-de-France et de l'Assistance Publique/H?pitaux de Paris (AP-HP) has elaborated a pragmatic approach for the monitoring of institutionally sponsored clinical studies. The mandatory practices aiming at preventing enrolled volunteers from risks and results from fraud and poor quality have been reviewed and a four-stage graduate monitoring has been defined, which is applied since 2002. This system needs to be scientifically assessed and adapted to the permanent evolution of national and international regulations. double dagger.     

Pattern of DNA synthesis in the meristematic cells of sinapis

Summary High-resolution autoradiographs were made of ultrathin sections in the shoot apex and the very young leaves of Sinapis alba fed with tritiated thymidine for 4 hours. Three types of labeled nuclei were found. (1) Those labeled in both the dispersed and the condensed chromatin, (2) those labeled only in the dispersed chromatin, and (3) those labeled only in the condensed chromatin.A distinct cytoplasmic labeling was found. Proplastids and mitochondria were the only significantly labeled entities in the cytoplasm. DNA synthesis in these organelles seems to be synchronized with DNA synthesis in the nucleus.This work was carried out at the Department of Botany, University of California, Berkeley, during the tenure of a fellowship from I.R.S.I.A. (Institut pour l'Encouragement de la Recherche Scientifique dans l'Industrie et l'Agriculture), Belgium.     

Discussing epigenetics in Southern California: A report from the International Symposium on Epigenetic Control and Cellular Plasticity,UCI, December 15–16, 2011

With the goal of discussing how epigenetic control and chromatin remodeling contribute to the various processes that lead to cellular plasticity and disease, this symposium marks the collaboration between the Institut National de la Santé et de la Recherche Médicale (INSERM) in France and the University of California, Irvine (UCI). Organized by Paolo Sassone-Corsi (UCI) and held at the Beckman Center of the National Academy of Sciences at the UCI campus December 15–16, 2011, this was the first of a series of international conferences on epigenetics dedicated to the scientific community in Southern California. The meeting also served as the official kick off for the newly formed Center for Epigenetics and Metabolism at the School of Medicine, UCI (http://cem.igb.uci.edu).     

Discussing epigenetics in Southern California: A report from the International Symposium on Epigenetic Control and Cellular Plasticity,UCI, December 15–16, 2011

With the goal of discussing how epigenetic control and chromatin remodeling contribute to the various processes that lead to cellular plasticity and disease, this symposium marks the collaboration between the Institut National de la Santé et de la Recherche Médicale (INSERM) in France and the University of California, Irvine (UCI). Organized by Paolo Sassone-Corsi (UCI) and held at the Beckman Center of the National Academy of Sciences at the UCI campus December 15–16, 2011, this was the first of a series of international conferences on epigenetics dedicated to the scientific community in Southern California. The meeting also served as the official kick off for the newly formed Center for Epigenetics and Metabolism at the School of Medicine, UCI (http://cem.igb.uci.edu).     

Allelism relationships between diuron-resistant, antimycin-resistant and funiculosin-resistant loci of the mitochondrial map in Saccharomyces cerevisiae.

Summary Using allelism tests, two diuron (DIU1, DIU2), one funiculosin (FUN1), and two antimycin (ANA1, ANA2) resistance loci are resolved into two mitochondrial drug-resistant genetic loci. DIU1 is allelic to ANA2 and FUN1. DIU2 is allelic to ANA1.Chercheur qualifié du Fonds National de la Recherche Scientifique     

Functional diversity within the rudimentary locus of Drosophila melanogaster

Summary The rudimentary locus of Drosophila melanogaster is shown to be at least bifunctional. Mutants in different regions of the locus have either no CPSase or no ATCase activity; some mutants lack both activities. The results are discussed in correlation with the complementation and genetic map of the locus.Supported by National Research Council of Canada, grant A-1764 and National Cancer Institute of Canada, grant 6051 to D. T. Suzuki.Researcher, Centre National de la Recherche Scientifique, France and recipient of European Molecular Biology Organization Fellowship.     

Laminin provides a better substrate than fibronectin for attachment,growth, and differentiation of 1003 embryonal carcinoma cells

Summary Culture of cells in hormonally defined media has allowed (a) the demonstration of physiological responses from cells usually unable to express them in vitro and (b) the study of the effects on growth and differentiation of diffusible factors and attachment factors. The embryonal carcinoma line 1003 forms multidifferentiated tumors in vivo but is unable to differentiate in vitro when grown in serum-containing medium. In a defined medium containing insulin, transferrin, selenium, and fibronectin as attachment factors, 1003 cells grow for several generations and differentiate into neurons and embryonic mesenchyme (Darmon et al., 1981, Dev. Biol. 85: 463–473). In the present work the effects of fibronectin and laminin were compared. In the presence of laminin the cells attached and spread better, grew faster, and could be plated at lower densities. Neurite extension was also better under these conditions and most importantly, it was found that laminin induced an important formation of muscular tissue when the cells had been seeded at low densities. Multinucleated myotubes could be stained with antibodies directed against embryonic muscular myosin. Coating the dishes with polylysine or adding FGF or serum-spreading factor to the medium allowed growth of low-density cultures with fibronectin instead of laminin but muscular differentiation was not detected under these conditions. Addition of fibronectin to laminin-containing medium did not inhibit muscular differentiation. Presented in the symposium on Plant and Animal Physiology in Vitro at the 33rd Annual Meeting of the Tissue Culture Association, San Diego, California, June 6–10, 1982. This research was supported in part by grants from the “Centre National de la Recherche Scientifique” (LA 269), the “Délégation Générale à la Recherche Scientifique et Technique,” the Fondation pour la Recherche Médicale Fran?aise,” the “Institut National de la Santé et de la Recherche Medicale,” the “Ligue Nationale Fran?aise centre le Cancer,” and the “Fondation André Meyer.” This symposium was supported in part by the following organizations: Bellco Glass, Inc., California Branch of the Tissue Culture Association, Collaborative Research, Hana Media, Hybridtech, K C Biological, Inc., and Millipore Corporation.     

Individualisation au microscope optique des grains de proteine secretes par la glande mammaire

Resumé Les grains de protéine sécrétés par la glande mammaire, révélés par le microscope électronique, peuvent s'individualiser au microscope optique à condition d'employer une technique assez fine.

---

Summary The protein granules secreted by the mammary gland and first revealed by electron microscopy can be seen in the light microscope, if appropriate techniques are emploied.

---

---

Avec l'aide du Centre National de la Recherche Scientifique et de l'Institut National de la Santé et de la Recherche Médicale.