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1.
Cell Mol Biol (Noisy-le-grand) ; 47(5): 935-46, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11728104

ABSTRACT

Physical states of cell-associated water in growing kidney beans was studied by NMR microscopy. 1H-NMR images indicated the changes of water amount in the individual tissues. The seed gradually reduced water and water in the tissues of the pod varied according to growth stages. Images that reflect diffusive motion provide different contrast from that of the proton images; signal intensity was maintained in the tissues containing small amounts of water and showing weak signal on the proton images. These images are related to the activity of metabolism and physiological functions. The parameter-images provided the structural information about cellular matrix, the barrier spacing of water compartments and the reduced permeability of cell-membranes surrounding the compartment, were created based on the restricted diffusion of cell-associated water. The properties of the water compartment changed with the stages of growth in individual tissues of the fruits. Two types of water compartments were detected; one had approximately 65 microm spacing and constant permeability (20-25%) throughout the stages of growth, and another had the smaller and variable spacing (approximately 35 microm), and a lower permeability. The former belongs to the seed and the mesocarp, the exocarp and the epidermis of the pod. While the latter characterizes the properties of the primary tissue in the pod, the endocarp, which increased with development of the pod then showed reduction with the decrease of water in the pod with the fruit growth.


Subject(s)
Phaseolus/growth & development , Water/metabolism , Biological Transport/physiology , Magnetic Resonance Spectroscopy/methods , Phaseolus/cytology , Phaseolus/metabolism
2.
Cell Mol Biol (Noisy-le-grand) ; 47(5): 959-70, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11728106

ABSTRACT

Old ideas often persist long after sound evidence dictates otherwise. I attempt to report one such case in the life sciences, by pointing out what are perceived to be fundamental flaws or questions in conventional wisdom. It is my experience that much evidence not in support of the well accepted membrane pump view of the living cell has been overlooked, forgotten or even ignored. In presenting this idea, the evolution of our knowledge from the establishment of cellular and protoplasmic theory to the emergence of solution theory is presented. The universal hypothesis based on physical chemical principles is presented, followed by the advent of the membrane-situated energy-requiring pump. The experimental demonstration of an inadequate energy supply for the first pump is discussed, followed by a review of new evidence that calls to question the use of dilute solution theory in describing adequately cellular function. Finally, roles for cellular water are suggested to explain the cellular exclusion of sodium and to serve as a barometer for the healthy state. Within the context of a metaphor, I attempt to qualitatively embrace the physical findings. It is concluded that the mobility of water molecules may be considered to change with the progression of normal tissue to a state of disease. These changes in the mobility of water molecules are "fingerprinted" by changes in the molecular motion of the solids.


Subject(s)
Cell Physiological Phenomena , Water/metabolism , Animals , Biological Transport , Cell Membrane/metabolism , Cytoplasm/chemistry , Cytoplasm/metabolism , Water/chemistry
3.
Biochim Biophys Acta ; 1426(1): 17-31, 1999 Jan 04.
Article in English | MEDLINE | ID: mdl-9878679

ABSTRACT

Morning glory seeds in dry conditions (0.099 g H2O/dry wt.) were exposed to electric fields and germinated. The physical state of water in the germinating seeds of both control and exposed groups were examined using 1H-NMR spectroscopy and NMR microscopy. Three water fractions were observed which were characterized by different relaxation times (T1) and chemical shifts. The average region containing long T1 fractions was approximately 50 micrometer in diameter and consisted of half-permeable barriers. The maximum intracellular water transport rate was 2.3x10-5 cm2/s. The treatment with electric field (500 kV/m for 60 min) increased the fraction with the shortest T1 and decreased that with the longest T1. Because the total water content in the treated seeds (3.4 g H2O/dry wt.) was similar to that in the untreated seeds (3.9 g H2O/dry wt.), the treated seeds held more water in a condition in restricted motion than the untreated seeds. It is thought that the membrane systems were affected by the electric polarization which led to an unusual accumulation of water and the hydration of stored macromolecules during the imbibition process. This set of events led to excessive swelling of stored macromolecules, resulting in the disruption of membrane systems and irregular organization of tissue structures.


Subject(s)
Electromagnetic Fields , Plants/radiation effects , Seeds/radiation effects , Water/chemistry , Cell Membrane/chemistry , Cell Membrane/radiation effects , Germination/radiation effects , Magnetic Resonance Spectroscopy/methods , Plants/chemistry , Seeds/cytology
4.
Arch Phys Med Rehabil ; 78(11): 1200-3, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9365349

ABSTRACT

OBJECTIVE: To determine if the chronic pain frequently presented by postpolio patients can be relieved by application of magnetic fields applied directly over an identified pain trigger point. DESIGN: Double-blind randomized clinical trial. SETTING: The postpolio clinic of a large rehabilitation hospital. PATIENTS: Fifty patients with diagnosed postpolio syndrome who reported muscular or arthritic-like pain. INTERVENTION: Application of active or placebo 300 to 500 Gauss magnetic devices to the affected area for 45 minutes. MAIN OUTCOME MEASURE: Score on the McGill Pain Questionnaire. RESULTS: Patients who received the active device experienced an average pain score decrease of 4.4 +/- 3.1 (p < .0001) on a 10-point scale. Those with the placebo devices experienced a decrease of 1.1 +/- 1.6 points (p < .005). The proportion of patients in the active-device group who reported a pain score decrease greater than the average placebo effect was 76%, compared with 19% in the placebo-device group (p < .0001). CONCLUSIONS: The application of a device delivering static magnetic fields of 300 to 500 Gauss over a pain trigger point results in significant and prompt relief of pain in postpolio subjects.


Subject(s)
Magnetics/therapeutic use , Pain Management , Postpoliomyelitis Syndrome/complications , Chi-Square Distribution , Chronic Disease , Double-Blind Method , Female , Humans , Male , Pain/etiology , Pain/physiopathology , Pain Measurement , Pilot Projects
5.
Med Hypotheses ; 44(1): 63-5, 1995 Jan.
Article in English | MEDLINE | ID: mdl-7539883

ABSTRACT

A three-part hypothesis for an objective end point for pain is presented: 1) chronic pain results in a characteristic, but reproducible, pattern for the distribution of T lymphocytes in the various phases of their cell cycle; 2) Significant reduction or complete loss of chronic pain will cause a reproducible change in the distribution of T lymphocytes in their cell cycle; 3) The change in T lymphocytes cell cycle distribution will be a function of the degree of recovery from the pain experience. A preliminary test of the hypothesis is presented. The cell cycle distribution of T cell lymphocytes was determined in a group of 10 subjects (experiencing chronic pain) before and after participating in a 10-day educotherapy program given by a master teacher. Associated with a significant reduction of pain was a highly significant shift of the T cell lymphocytes into the S phase of the cell cycle. This observation is consistent with parts one and two of the hypothesis.


Subject(s)
Cell Cycle/physiology , Pain Management , Palliative Care/methods , T-Lymphocytes/physiology , Chronic Disease , Flow Cytometry , Humans , Lymphocyte Count , Pain/physiopathology , Philosophy , T-Lymphocytes/cytology
6.
Alcohol ; 11(6): 571-6, 1994.
Article in English | MEDLINE | ID: mdl-7865160

ABSTRACT

The traditional belief about ethanol's mechanism of action is based on ethanol's lipophilicity and capability to penetrate and disorder lipid bilayers. This traditional belief is now being supplanted by growing evidence that ethanol has relatively selective actions on certain synaptic receptors, such as those for NMDA, serotonin, and GABA. It was recently argued that these receptor specificities are secondary to a preferential ability of ethanol to displace membrane bound water in the domains of certain receptors. The data obtained in this study are consistent with the original hypothesis: any disorganization of cellular water by ethanol will be detectable by proton nuclear magnetic resonance (NMR) spectroscopy. In particular, the relaxation times of water hydrogen protons reflect how constrained water molecules are by the macromolecules within cells. The relaxation time of "bulk" water is lengthened relative to water molecules that are under the influence of electromagnetic fields of macromolecular surfaces within cells. Here, we tested this hypothesis in living fish, which dosed themselves by swimming in water that had added ethanol. Estimates of brain alcohol at 5 min after initial exposure revealed that the brain concentration was only about 1/3 that of the water in which they were swimming. The average value of the NMR relaxation time T1, but not T2, was decreased at 5 min (when brain concentrations were on the order 100 mM) and reached statistical significance at 10 and 30 min after initial exposure.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Body Water/metabolism , Brain/metabolism , Cyprinidae/metabolism , Ethanol/pharmacology , Magnetic Resonance Spectroscopy , Animals , Brain/drug effects , Ethanol/cerebrospinal fluid , Protons
7.
J Cell Physiol ; 159(2): 197-204, 1994 May.
Article in English | MEDLINE | ID: mdl-8163560

ABSTRACT

The plasma membrane of erythrocytes, as of other cells, is thought to act as the barrier responsible for maintaining intracellular gradients of most ions and small molecular species between the cell and its environment. Controlled application of the nonionic detergent Brij 58 effectively opened the erythrocyte plasma membrane, as judged by electron microscopy and lipid mobilization, but the cytoplasm maintained much of its integrity for about 30 min. Release of K+ correlated well with release of protein into the surrounding medium. The results demonstrate that permeabilization of the erythrocyte plasma membrane does not result in an instantaneous equilibration of small ions, such as K+, between the cell and its environment. A comparison was made between erythrocytes treated with Brij 58 and Triton X-100. The lipid and protein solubilizing actions of Triton X-100 were not as easily separable in time as those of Brij 58. The results of treatment of the erythrocytes with different types of nonionic detergents suggest that the membranolytic and cytoplasmic protein destabilizing actions of nonionic detergents correspond with their hydrophilic-lipophilic balance numbers (HLB values).


Subject(s)
Blood Proteins/metabolism , Erythrocytes/metabolism , Lipids/blood , Octoxynol/pharmacology , Potassium/blood , Animals , Cetomacrogol/pharmacology , Chickens/blood , Electrophoresis, Polyacrylamide Gel , Erythrocytes/drug effects , Erythrocytes/ultrastructure , Kinetics , Polidocanol , Polyethylene Glycols/pharmacology
8.
Magn Reson Med ; 19(2): 214-6, 1991 Jun.
Article in English | MEDLINE | ID: mdl-1881305

ABSTRACT

The purpose of this paper is to present an overview of the diffusive behavior of water in biological tissues. The analysis shows that obstructive barriers would have to occupy very large volume fractions in order to account for the reduction in the diffusion coefficient (D) observed in biological systems. Generally, most models lead to the supposition that a substantial fraction (20-40%) of the cell water is hydration water, or that the diffusion coefficient of the cytoplasmic water is reduced substantially from the free water value. Thus, the conclusion that a substantial fraction of cell water has diffusive properties that are altered by the macromolecules of the cytoplasm seems inescapable. The impact of these findings on MRI remain to be determined.


Subject(s)
Body Water/metabolism , Magnetic Resonance Imaging , Cells/metabolism , Diffusion , Humans , Tissue Distribution
9.
J Cell Physiol ; 146(3): 394-8, 1991 Mar.
Article in English | MEDLINE | ID: mdl-2022694

ABSTRACT

The release of sodium and potassium and the uptake of sucrose molecules was studied in pig lenses incubated in isosmotic sucrose solution in either the presence or absence of 1% Triton X-100 (a non-ionic detergent). This Triton X-100 treatment has been shown to cause severe disruptions of cell membrane integrity. If sodium and potassium were free in the lens fibers as in a dilute aqueous solution, they would be expected to diffuse three to four times faster than sucrose. However, measurements of sodium and potassium release and sucrose uptake in the Triton X-100 treated lenses show a 1:1 equilibration. When pig lenses were incubated in the same solution without detergent, the sucrose uptake was significantly less than the potassium and sodium release. It is postulated that a slow, detergent mediated collapse of protein-water-ion interactions within the lens is the rate-limiting step of the observed equilibration of monovalent cations and sucrose molecules.


Subject(s)
Lens, Crystalline/metabolism , Polyethylene Glycols/pharmacology , Potassium/pharmacokinetics , Sodium/pharmacokinetics , Sucrose/pharmacokinetics , Animals , Biological Transport/drug effects , Biological Transport/physiology , Culture Techniques , Lens, Crystalline/drug effects , Lens, Crystalline/physiology , Octoxynol , Swine/metabolism , Swine/physiology , Water-Electrolyte Balance/drug effects , Water-Electrolyte Balance/physiology
10.
Scanning Microsc Suppl ; 5(4): S1-9; discussion S9-10, 1991.
Article in English | MEDLINE | ID: mdl-1822018

ABSTRACT

A method is presented for obtaining simple approximate solutions for the problem of self-diffusion in an ordered array of obstacles. Our results are compared with some previous exact and approximate solutions, and we find that our method agrees well with the exact results over a large range of the volume fraction of the obstructions. It is shown that there is an important distinction between measurements of the diffusion coefficient by the capillary flow method and the spin-echo method. The modifications for the spin-echo case are given and applied to recent measurements on the anisotropy of the self-diffusion of water in striated muscle and to measurements on cysts of the brine shrimp. The analysis shows that very large volume fractions of obstructive barriers are required in order to account for the reduction in the diffusion coefficient in biological systems. Thus this model analysis leads to the supposition that a substantial fraction (20-40%) of the cell water is hydration water, or that the diffusion coefficient of the cytoplasmic water is reduced substantially from the free water value. In either case, the conclusion that a substantial fraction of cell water has diffusive properties that are altered by the macromolecules of the cytoplasm seems inescapable. In the case of NMR methodology, the measuring times are such that the values for diffusion are often influenced by the presence of macromolecular structures (obstructions) within the cells. This suggests that obstructions make a significant contribution to the value of the NMR diffusion coefficient and that NMR may have practical value for the evaluation of obstruction effects.


Subject(s)
Magnetic Resonance Spectroscopy , Water/metabolism , Animals , Artemia , Biological Transport , Diffusion , Erythrocytes/metabolism , Humans , Mathematics , Muscles/metabolism
11.
Scanning Microsc ; 4(2): 457-64; discussion 464-6, 1990 Jun.
Article in English | MEDLINE | ID: mdl-2205910

ABSTRACT

The relationship between ions, water, and the electrical properties are fundamental to our understanding of cellular function. This paper is primarily directed at reviewing the theoretical explanations for the changes in cellular potential and ionic composition which are associated with early postnatal development of skeletal muscle. The findings are: (a) a two-fold reduction in tissue hydration and a significant reduction of the diffusive motion of cellular water; (b) ten-fold decrease in cellular sodium; (c) six-fold decrease in tissue chloride; (d) the concentrations of intracellular potassium, and of extracellular sodium, potassium and chloride were constant; and (e) the cellular potential changed by 55 mV. A review of the literature concerning the physical state of potassium and water is made. The theoretical explanations of these findings are evaluated in terms of the classical membrane theory and the association induction hypothesis.


Subject(s)
Cell Physiological Phenomena , Muscles/physiology , Potassium/physiology , Animals , Humans , Membrane Potentials
12.
Physiol Chem Phys Med NMR ; 22(4): 219-28, 1990.
Article in English | MEDLINE | ID: mdl-2101934

ABSTRACT

Magnetic resonance (MR) images of three major flight muscles of chicks were obtained with surface coils using a 0.3 Tesla whole body imaging system (FONAR Beta 3000). The two fast muscles, pectoralis major (PM) and posterior latissimus dorsi (PLD), and a slow muscle, anterior latissimus dorsi (ALD), were identified in the axial, coronal, and sagittal images. The signal intensity (SI) of each muscle was electronically measured and its ratio to the background noise (S/N) was determined. Although visually the three muscles showed intermediate SI, the slow and fast muscles could be differentiated on the basis of their S/N values. These values were invariably higher in the slow muscles than in the fast muscles. To understand these differences, the muscles were excised and their mono- and multiexponential MR relaxation times (T1 and T2) were determined at 30 MHz. Multiexponential analysis enhanced the differences between the muscle types. With the sole exception of short T2, all relaxation components of the slow muscles were significantly longer than those of the fast muscles. These results suggest that elevation in the S/N, T1 and T2 values of muscles may not necessarily indicate a pathologic event, but may reflect the preponderance of slow fibers.


Subject(s)
Muscles/anatomy & histology , Animals , Chickens , Magnetic Resonance Imaging , Muscle Relaxation , Muscles/physiology , Thorax/anatomy & histology , Thorax/physiology
13.
Biophys J ; 58(2): 483-91, 1990 Aug.
Article in English | MEDLINE | ID: mdl-19431762

ABSTRACT

The dormant cysts of Artemia undergo cycles of hydration-dehydration without losing viability. Therefore, Artemia cysts serve as an excellent intact cellular system for studying the dynamics of water-protein interactions as a function of hydration. Deuterium spin-lattice (T(1)) and spin-spin (T(2)) relaxation times of water in cysts hydrated with D(2)O have been measured for hydrations between 1.5 and 0.1 g of D(2)O per gram of dry solids. When the relaxation rates (I/T(1), I/T(2)) of (2)H and (17)O are plotted as a function of the reciprocal of hydration (1/H), an abrupt change in slope is observed near 0.6 g of D(2)O (or H(2) (17)O)/gram of dry solids, the hydration at which conventional metabolism is activated in this system. The results have been discussed in terms of the two-site and multisite exchange models for the water-protein interaction as well as protein dynamics models. The (2)H and (17)O relaxation rates as a function of hydration show striking similarities to those observed for anisotropic motion of water molecules in protein crystals.It is suggested here that although the simple two-site exchange model or n-site exchange model could be used to explain our data at high hydration levels, such models are not adequate at low hydration levels (<0.6 g H(2)O/g) where several complex interactions between water and proteins play a predominant role in the relaxation of water nuclei. We further suggest that the abrupt change in the slope of I/T(1) as a function of hydration in the vicinity of 0.6 g H(2)O/g is due to a change in water-protein interactions resulting from a variation in the dynamics of protein motion.

14.
Scanning Microsc ; 3(4): 1241-3; discussion 1244-5, 1989 Dec.
Article in English | MEDLINE | ID: mdl-2633341

ABSTRACT

The action of detergents is thought to be connected primarily with micelle formation. However, detergent monomers can also effect biological systems. It was found in this study that human red blood cells can be disintegrated with Triton X-100 non-ionic detergent at a concentration of 0.007%, lower than the critical micellar concentration (CMC). The time dependent release of hemoglobin and potassium was detected at 37 degrees C and both were sigmoid in character. Although potassium was released faster than hemoglobin, a cooperative relationship between potassium and hemoglobin within the intact red blood cell is suggested by this observation.


Subject(s)
Erythrocytes/metabolism , Hemoglobins/pharmacokinetics , Polyethylene Glycols , Potassium/pharmacokinetics , Erythrocytes/drug effects , Female , Humans , In Vitro Techniques , Male , Octoxynol
15.
Biomed Biochim Acta ; 48(5-6): S548-51, 1989.
Article in English | MEDLINE | ID: mdl-2757629

ABSTRACT

We are proposing that cellular water becomes organized through its interaction with the various macromolecular (particularly protein) matrices of the cell. And a physical consequence of this interaction results in an orderly exclusion of solutes from the aqueous cytoplasm. This orderly solute exclusion, dependent on physical properties of each solute, along with selective electrostatic adsorption of ions determine the total cellular solute concentration in mature cells. We are proposing further that during early postnatal development the water-macromolecular interaction induces less order and high concentrations of sodium can occur. Finally, our current view of cell water may have been in Albert Szent-Gyorgyi's mind when he stated in 1972 that: "Sixty years of research has taught me to look upon water as part and parcel of the living machinery, if not the hub of life. Water is the most extraordinary substance! Partically all its properties are anomalous, which enabled life to use it as building material for its machinery. Life is water dancing to the tune of solids".


Subject(s)
Body Water , Muscle Development , Animals , Chemical Phenomena , Chemistry, Physical , Muscles/cytology , Muscles/physiology , Rats
16.
J Cell Physiol ; 137(2): 299-304, 1988 Nov.
Article in English | MEDLINE | ID: mdl-3056959

ABSTRACT

Ultrastructural observations in combination with electron probe X-ray microanalysis on detergent (Brij 58) permeabilized (disruption of the plasma membrane) nucleated chicken erythrocytes support the view that a large fraction of cytoplasmic and nuclear K+ is not freely diffusible and that adsorption of K+ on detergent released mobilizable proteins exists within the cell. The data also suggest that the detergent proteins are normally immobilized by a detergent-resistant cytoskeleton so that they are not immediately free to diffuse from the cell for several minutes after detergent disruption of the plasma membrane.


Subject(s)
Cell Membrane/physiology , Erythrocytes/cytology , Extracellular Matrix/physiology , Animals , Chickens , Electron Probe Microanalysis , Microscopy, Electron , Microscopy, Phase-Contrast
17.
Scanning Microsc ; 2(1): 267-73, 1988 Mar.
Article in English | MEDLINE | ID: mdl-3259334

ABSTRACT

Nonionic detergents, Triton X-100 and Brij 58, removed, within 2-5 minutes, lipid membrane of suspended thymus lymphocytes and monolayer H-50 cells grown in culture. Studies of hydration, ionic asymmetry, and ionic and protein release kinetics were conducted on these membraneless cellular preparations. The hydration of nuclei isolated by Triton X-100 procedures appears to be influenced strongly by the monovalent ionic concentration of the buffer bathing the organelles. The putative monovalent ionic concentration of the cellular aqueous phase (i.e., 150 meq/L) caused nuclei to swell and coalesce. Monovalent ionic concentrations of 30 meq/L or less caused minimal changes in volume and in morphology. Triton X-100 treatment led to rapid mobilization and solubilization of membrane and cytoplasmic lipids and proteins, and the cellular potassium was reduced to very low levels. Brij 58 treatment of the lymphocytes for 5 minutes led to loss of membrane structure. Potassium, however, was retained at significant levels for over 10 minutes. Potassium and protein release kinetic studies in the H-50 monolayer cells following Brij treatment revealed that potassium and the detergent mobilized proteins may be co-compartmentalized and that 10 minutes or more are required before their release is completed. These results support the view that most of the potassium and "diffusible" proteins are not fully dissolved in the cellular water. Furthermore, the integrity of the membranes does not appear to be essential for the retention of the ions and the proteins.


Subject(s)
Body Fluids/analysis , Cell Membrane Permeability , Detergents/pharmacology , Intracellular Fluid/analysis , Metals/analysis , Surface-Active Agents/pharmacology , T-Lymphocytes/ultrastructure , Animals , Cations , Cattle , Cell Line , Microscopy, Electron/methods , Microscopy, Electron, Scanning/methods , T-Lymphocytes/drug effects
18.
Physiol Chem Phys Med NMR ; 20(1): 15-22, 1988.
Article in English | MEDLINE | ID: mdl-3406136

ABSTRACT

Two human colon cancer cell lines grown in tissue culture were found to have significantly different Nuclear Magnetic Resonance (NMR) relaxation times of water protons in the fresh, intact state and after fragmentation into subcellular fractions. Differences in the protein composition of the subcellular fractions were also demonstrated by protein analysis and gel chromatography. In further studies, these cell lines may be useful to investigate the biochemical basis for the disparity in relaxation times of water protons between tissues which constitutes the basis for Magnetic Resonance Imaging (MRI) tissue contrast.


Subject(s)
Colonic Neoplasms/pathology , Cell Division , Cell Line , Freezing , Humans , Magnetic Resonance Spectroscopy/methods
19.
J Surg Oncol ; 36(1): 1-4, 1987 Sep.
Article in English | MEDLINE | ID: mdl-3041112

ABSTRACT

Proton NMR spectroscopy and imaging of human breast tissue have provided new methods in studying breast carcinomas. Continuous wave proton NMR spectroscopy in this study is able to discriminate breast carcinomas from normal breast tissue on the basis of the integrated area under the water and lipid peaks, width at half height of the water peak, and chemical shift of the lipid peak. In addition, the NMR parameters were correlated with the following clinical and pathologic prognostic indices: TNM tumor stage, nuclear grade, and estrogen receptor status (ER). Width at half height of the lipid peak (1/2 delta lipid) correlated with tumor content and ER. Studies using higher resolution proton or phosphorus NMR spectra may separate signals that can correlate with biological information on breast neoplasms useful to the clinician. Chemical shift of the lipid peak may be used to sharpen contrast on MRI of breast tumors.


Subject(s)
Breast Neoplasms/diagnosis , Breast/pathology , Magnetic Resonance Spectroscopy , Adenofibroma/analysis , Adenofibroma/diagnosis , Adenofibroma/pathology , Breast/analysis , Breast Neoplasms/analysis , Breast Neoplasms/pathology , Carcinoma/analysis , Carcinoma/diagnosis , Carcinoma/pathology , Carcinoma, Intraductal, Noninfiltrating/analysis , Carcinoma, Intraductal, Noninfiltrating/diagnosis , Carcinoma, Intraductal, Noninfiltrating/pathology , Female , Humans , Lipids/analysis , Receptors, Estrogen/analysis
20.
Physiol Chem Phys Med NMR ; 19(1): 3-8, 1987.
Article in English | MEDLINE | ID: mdl-3615642

ABSTRACT

Rat liver cell nuclei isolated in the presence of Ca++ and Mg++ ions were exposed to citrate buffer at different pH levels. Their morphology was studied with the electron microscope and the water content measured. At a low pH the chromatin remained compact, but at neutral pH an intense fibrillarization of the chromatin was observed; and, seemed to be reversible, because of deoxyribonucleoproteins (DNP) filaments which dispersed at a pH of 7 were repacked to their previous site at a pH of 3. The ribonucleo-proteins (RNP)-containing structures did not show the same reversible fibrillarization. In addition to the morphological changes, a large increase in the water content ("water-holding capacity") of the chromatin structures was observed.


Subject(s)
Cell Nucleus/ultrastructure , Liver/ultrastructure , Animals , Cell Fractionation/methods , Chromatin/ultrastructure , Hydrogen-Ion Concentration , Male , Microscopy, Electron/methods , Rats , Rats, Inbred Strains
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