scholarly journals THE ISOLATION OF CELL NUCLEI IN NON-AQUEOUS MEDIA

1952 ◽  
Vol 35 (3) ◽  
pp. 529-557 ◽  
Author(s):  
V. Allfrey ◽  
H. Stern ◽  
A. E. Mirsky ◽  
H. Saetren
Keyword(s):  
Citric Acid ◽  
Serum Proteins ◽  
Aqueous Media ◽  
Organic Media ◽  
Cell Nuclei ◽  
Intracellular Enzyme ◽  
Cytoplasmic Proteins ◽  
Immunological Tests ◽  
Avian Erythrocytes ◽  
Enzyme Distribution

1. A modified Behrens procedure is described for the isolation of nuclei from avian erythrocytes and from the liver, kidney, thymus, pancreas, heart, and intestinal mucosa of the calf or horse. 2. The purity of these nuclei has been established by staining reactions, enzyme studies, and immunological tests for serum proteins. 3. Evidence is presented to show that a transport of cytoplasmic proteins into the nucleus does not occur during the isolation. 4. Nuclei prepared in non-aqueous media contain considerably more protein and a very different enzyme composition from that observed in nuclei prepared by "homogenization" techniques in dilute citric acid. 5. The suitability of nuclei prepared in organic media for the study of intracellular enzyme distribution is discussed.

scholarly journals Quantification of Cell Nuclei Isolated from Hepatocytes by Cell Lysis with Nonionic Detergent in Citric Acid.

1991 ◽  
Vol 16 (3) ◽  
pp. 203-207 ◽  
Author(s):  
Yoshifumi Horiuti ◽  
Motohiro Ogishima ◽  
Kazuo Yano ◽  
Yuzo Shibuya
Keyword(s):  
Citric Acid ◽  
Cell Lysis ◽  
Cell Nuclei ◽  
Nonionic Detergent

scholarly journals UPTAKE OF GLYCINE-N15 BY COMPONENTS OF CELL NUCLEI

1952 ◽  
Vol 36 (2) ◽  
pp. 173-179 ◽  
Author(s):  
Marie M. Daly ◽  
V. G. Allfrey ◽  
A. E. Mirsky
Keyword(s):  
Metabolic Rates ◽  
Cytoplasmic Protein ◽  
Cell Nuclei ◽  
Residual Protein ◽  
Avian Erythrocytes ◽  
Mammalian Liver

1. The uptake of glycine-N15 by components of cell nuclei was studied. The nuclear components were derived both from tissues with high metabolic rates-mammalian liver, kidney, and pancreas-and from cells with relatively low rates of metabolism-avian erythrocytes and echinoderm sperm. N15 uptake by nuclear components of liver, kidney, and pancreas was far more rapid than by those of erythrocytes and sperm. 2. The nuclear components of liver, kidney, and pancreas for which measurements were made were DNA, histone, and residual protein of chromatin. Uptake into DNA was low, into histone higher, and into residual protein much higher still, being comparable with that into mixed cytoplasmic protein. 3. A comparison of the uptake of N15 by the chromosomal components, histone and DNA of liver, pancreas, and kidney showed that chromosomal "activity" varies in different cells and also in the same cell depending upon its over-all activity.

The effect of ligand, solvent and Cu(0) source on the efficient polymerization of polyether acrylates and methacrylates in aqueous and organic media

2015 ◽  
Vol 6 (32) ◽  
pp. 5940-5950 ◽  
Author(s):  
Alexandre Simula ◽  
Vasiliki Nikolaou ◽  
Fehaid Alsubaie ◽  
Athina Anastasaki ◽  
David M. Haddleton
Keyword(s):  
Radical Polymerization ◽  
Aqueous Media ◽  
Organic Media ◽  
Reversible Deactivation ◽  
Reversible Deactivation Radical Polymerization

The synthesis of well-defined telechelic polyacrylates and polymethacrylates in organic and aqueous media via Cu(0)-mediated reversible-deactivation radical polymerization is thoroughly investigated.

scholarly journals The Effect of the PVA/Chitosan/Citric Acid Ratio on the Hydrophilicity of Electrospun Nanofiber Meshes

Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3557
Author(s):  
Zsuzsanna Czibulya ◽  
Attila Csík ◽  
Ferenc Tóth ◽  
Petra Pál ◽  
István Csarnovics ◽  
...  
Keyword(s):  
Citric Acid ◽  
Polyvinyl Alcohol ◽  
Aqueous Media ◽  
Physical Parameters ◽  
Negative Effects ◽  
Force Microscopy ◽  
Angle Measurements ◽  
Acid Ratio ◽  
Cross Linkage ◽  
Dental Applications

In this study, scaffolds were prepared via an electrospinning method for application in oral cavities. The hydrophilicity of the fiber mesh is of paramount importance, as it promotes cell spreading; however, the most commonly used polyvinyl alcohol (PVA) and other hydrophilic fiber meshes immediately disintegrate in aqueous media. In contrast, the excessive hydrophobicity of the scaffolds already inhibits cells adhesion on the surface. Therefore, the hydrophilicity of the fiber meshes needed to be optimized. Scaffolds with different polyvinyl alcohol (PVA)/chitosan/citric acid ratios were prepared. The addition of chitosan and the heat initiated cross-linkage of the polymers via citric acid enhanced the scaffolds’ hydrophobicity. The optimization of this property could be followed by contact angle measurements, and the increased number of cross-linkages were also supported by IR spectroscopy results. The fibers’ physical parameters were monitored via low-vacuum scanning electron microscopy (SEM) and atomic force microscopy (AFM). As biocompatibility is essential for dental applications, Alamar Blue assay was used to prove that meshes do not have any negative effects on dental pulp stem cells. Our results showed that the optimization of the fiber nets was successful, as they will not disintegrate in intraoral cavities during dental applications.

Bioactive Ceramic And Model Surfaces Adsorb Ligands and Factors That Stimulate Cellular Function

2000 ◽  
Vol 6 (S2) ◽  
pp. 992-993
Author(s):  
Russell J. Composto ◽  
Paul Ducheyne ◽  
Elsie Effah Kaufman
Keyword(s):  
Bioactive Glass ◽  
Serum Proteins ◽  
Rutherford Backscattering Spectrometry ◽  
Ionic Composition ◽  
Aqueous Media ◽  
Force Microscopy ◽  
Atomic Force ◽  
Kinetics Of Formation ◽  
Physical And Chemical

Microscopy and microanalysis techniques have played an important role in our understanding of how biomaterials interact with their environment. In first part of this study, we will focus on the behavior of bioactive glass, whereas in the second a model surface will be investigated. Upon implantation bioactive glass undergoes a series of reactions that leads to the formation of a calcium phosphate-rich layer. Most in vitro studies of the changes that occur on the surface of bioactive glass have employed the use of buffer solutions with compositions reflecting the ionic composition of interstitial fluid. Although these studies have documented the physical and chemical changes associated with bioactive glass immersed in aqueous media, they do not reveal the effect of serum proteins and cells which are present at the implantation site. In the present study, we document, using atomic force microscopy (AFM) and Rutherford backscattering spectrometry (RBS), significant differences in reaction layer composition, thickness, morphology and kinetics of formation arising from the presence of serum proteins.

A green adsorbent for the removal of BTEX from aqueous media

RSC Advances ◽  
2016 ◽  
Vol 6 (17) ◽  
pp. 14290-14305 ◽  
Author(s):  
M. Arshadi ◽  
H. Shakeri ◽  
J. W. L. Salvacion
Keyword(s):  
Citric Acid ◽  
Adsorption Mechanism ◽  
Aqueous Media ◽  
Green Adsorbent ◽  
Benzene Toluene

Ostrich bone waste (OBW) was modified chemically with citric acid and used as a bioadsorbent. The uptake of benzene, toluene, ethylbenzene, andp-xylene (BTEX) and the adsorption mechanism of BTEX by the green adsorbent (OBW-NaOH–CA) were studied.

Movement of Cytoplasmic Proteins into Nuclei Induced to Enlarge and Initiate DNA or RNA Synthesis

1969 ◽  
Vol 5 (2) ◽  
pp. 333-349 ◽  
Author(s):  
R. W. MERRIAM
Keyword(s):  
Protein Synthesis ◽  
Initial Period ◽  
Nuclear Material ◽  
Nucleic Acid Metabolism ◽  
Cell Nuclei ◽  
Material Loss ◽  
Brain Nuclei ◽  
Cytoplasmic Proteins ◽  
Chromosomal Changes ◽  
Nuclear Enlargement

In other studies it has been shown that somatic cell nuclei, which normally do not divide, are induced to enlarge and synthesize DNA when introduced into the cytoplasm of egg cells of Xenopus laevis. Introduction of such nuclei into the cytoplasm of large oocytes, however, causes nuclei to enlarge in a different way and to synthesize RNA but not DNA. In this study the proteins of eggs and oocytes were labelled with radioactive amino acids. Brain or blastula nuclei were then injected into cells containing labelled proteins under conditions in which protein synthesis was inhibited. Movement of cytoplasmic proteins was studied by observing the increase in acid-insoluble label over the injected nuclei by quantitative autoradiography. To prevent nuclear protein synthesis during the experiments, puromycin was injected with the nuclei. An estimation of the size of the labelled amino acid pool, a demonstration of the inhibitory effects of puromycin, and comparison of the amount of labelled material with and without puromycin all showed that protein synthesis in the nuclei played an insignificant role during the course of the experiments. A movement of acid-insoluble label from cytoplasm of egg cells into injected brain nuclei was noted even before they had begun to swell or synthesize DNA. In the initial period of nuclear enlargement there was a disappearance of the heterochromatic clumps characteristic of brain nuclei. This period coincided with a very rapid uptake of label to concentrations about twice that of the surrounding cytoplasm. A subsequent phase of nuclear swelling was characterized by a dilution of stainable nuclear material, loss of basophilia, and establishment of acidophilia of the nuclear contents. Cytoplasmic proteins continued to enter nuclei during this phase, but at a slower rate. Extraction of the soluble materials of labelled eggs with 0.01 M NaCl at pH 7.8 and a subsequent fractionation of the extract showed that there were many radioactive compounds present with molecular weights greater than 5000. The synthesis of DNA was initiated even before nuclear swelling could be detected, proceeding at least through the early stages of swelling. The induction of enlargement in blastula nuclei by oocyte cytoplasm containing labelled proteins was also accompanied by an uptake of label from the cytoplasm. In this case, although the uptake of unlabelled acidophilic material was much greater, the uptake of labelled proteins was much slower than that observed in the egg. The results are discussed in terms of chromosomal changes which occur during nuclear enlargement and during concomitant changes in nucleic acid metabolism.

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