scholarly journals Ultracentrifuge studies of histone fractions from calf thymus deoxyribonucleoprotein

1969 ◽  
Vol 114 (2) ◽  
pp. 227-235 ◽  
Author(s):  
P A Edwards ◽  
K V Shooter
Keyword(s):  
Sodium Chloride ◽  
Guanidine Hydrochloride ◽  
Chloride Concentration ◽  
Sedimentation Coefficient ◽  
Apparent Molecular Weight ◽  
Concentrated Solutions ◽  
Molecular Weights ◽  
Sodium Chloride Solutions ◽  
Low Concentrations ◽  
Calf Thymus

Molecular weights and sedimentation coefficients of four major fractions of calf thymus histones were measured. The minimum molecular weights were determined in concentrated solutions of guanidine hydrochloride. The results indicate that, with the possible exception of fraction F3, the fractions are heterogeneous. Comparisons in 0·1m-sodium chloride suggest that fraction F1 does not aggregate and show that fractions F2(a) and F3 aggregate to form larger complexes than does fraction F2(b). The degree of aggregation of each fraction is independent of pH in the range pH1–7. Detailed studies with fraction F2(b) have confirmed that the change in sedimentation coefficient observed as the sodium chloride concentration of the solution is increased results from increases in the apparent molecular weight of the sedimenting units. It has been found that the molecules of fraction F2(b) are present as single molecules only in sodium chloride solutions of 33mm or less. At these low concentrations the effects of charge greatly increase the concentration dependence of the sedimentation rate; the results can, however, be interpreted by using the theory developed by Alexandrowicz & Daniel (1963) and Daniel & Alexandrowicz (1963).

The Quantab strip in the measurement of urinary chloride and sodium concentrations.

1984 ◽  
Vol 30 (10) ◽  
pp. 1705-1707 ◽  
Author(s):  
P J Sloan ◽  
G Beevers ◽  
F E Baxter
Keyword(s):  
Sodium Chloride ◽  
Chloride Concentration ◽  
Sodium Concentration ◽  
Epidemiological Studies ◽  
Observer Variation ◽  
Salt Diet ◽  
Sodium Chloride Solutions ◽  
Urinary Chloride ◽  
Chemical Assay ◽  
Low Salt

Abstract The "Quantab" strip (Ames) measures chloride in fluids. For sodium chloride solutions and urine we found very good correlations between the Quantab reading and the chloride concentration as measured by chemical assay (r = 0.95 for chloride and r = 0.85 for sodium in urine). The strip gave reproducible results over the temperature range 4 to 37 degrees C. There was very little inter- and intra-observer variation in reading the strip. Although 10 to 23 min is required to complete the reaction, the strip reading is stable thereafter. We suggest that the strip could be useful in epidemiological studies of urinary sodium concentration and clinically in helping patients adhere to a low-salt diet.

Differences between deep pain responses to hypertonic and hypotonic saline solutions

1962 ◽  
Vol 17 (5) ◽  
pp. 841-843 ◽  
Author(s):  
Murray E. Jarvik ◽  
B. Berthold Wolff
Keyword(s):  
Sodium Chloride ◽  
Human Subjects ◽  
Chloride Concentration ◽  
Gluteus Medius ◽  
Aqueous Sodium ◽  
Sodium Chloride Solutions ◽  
Hypotonic Saline ◽  
Saline Solutions ◽  
Subjective Reports ◽  
Pain Responses

Different concentrations of both hypertonic and hypotonic aqueous sodium chloride solutions (0.2 ml) were injected into 24 hypodermic needles inserted in the gluteus medius muscles of 12 human subjects. It was found that a) both duration and intensity of deep pain responses were related to sodium chloride concentration; b) both latency and duration of pain responses were significantly greater with hypertonic than with hypotonic saline solutions; and c) hypertonic saline tended to induce subjective reports of a diffuse, dull ache, whereas hypotonic saline produced descriptions of a sharp, pricking, and well-localized pain. Submitted on April 3, 1962

scholarly journals Self-association of dermatan sulphate proteoglycans from bovine sclera

1981 ◽  
Vol 197 (2) ◽  
pp. 483-490 ◽  
Author(s):  
L Cöster ◽  
L A Fransson ◽  
J Sheehan ◽  
I A Nieduszynski ◽  
C F Phelps
Keyword(s):  
Molecular Weight ◽  
Light Scattering ◽  
Guanidine Hydrochloride ◽  
Apparent Molecular Weight ◽  
Sedimentation Equilibrium ◽  
Gel Chromatography ◽  
Side Chains ◽  
Dermatan Sulphate ◽  
Molecular Weights ◽  
High Particle

1. Two proteodermatan sulphate fractions (I and II) from bovine sclera were studied by gel chromatography, light-scattering and ultracentrifugation under various conditions. 2. Gel chromatography of proteoglycans in the absence or presence of hyaluronate was performed under associative conditions. No effect on the elution profile was noted. 3. Ultracentrifugation experiments (sedimentation-velocity and sedimentation-equilibrium) with proteoglycan I and II in 6 M-guanidine hydrochloride gave molecular weights (Mw) of 160000-220000 and 70000-100000 respectively. As the protein contents were 45% and 60% respectively, it may be calculated that proteoglycan I contained four to five side chains, whereas proteoglycan II contained one or two. Sedimentation-equilibrium runs performed in 0.15 M-NaCl gave an apparent molecular weight (Mw) of 500000-800000 for proteoglycan I and 90000-110000 for proteoglycan II. 4. In light-scattering experiments both proteoglycans I and II yielded high particle weights in 0.15 M-NaCl (3.1 × 10(6) and 3.4 × 10(6) daltons respectively). In the presence of 6 M-guanidine hydrochloride the molecular weights decreased to 410000 and 130000 respectively. The particle weights in 0.15 M-NaCl were not altered by the addition of hyaluronate or hyaluronate oligosaccharides. 5. The dermatan sulphate side chains of scleral proteoglycans (L-iduronate/D-glucuronate ratio 7:13) gave a particle weight of 100000 daltons in 0.15 M-NaCl. In 1.00 M-KCl/0.02M-EDTA the molecular weight was 24000. Addition of free scleral dermatan sulphate chains to a solution of proteoglycan II promoted further multimerization of the macromolecule.

scholarly journals Repassivation Potential of Alloy 22 in Sodium and Calcium Chloride Brines

2008 ◽  
Vol 1107 ◽  
Author(s):  
Raul B. Rebak ◽  
Gabriel O. Ilevbare ◽  
Ricardo M. Carranza
Keyword(s):  
Sodium Chloride ◽  
Calcium Chloride ◽  
Crevice Corrosion ◽  
Nitrate Concentration ◽  
Chloride Concentration ◽  
Chloride Solutions ◽  
Sodium Chloride Solutions ◽  
Repassivation Potential ◽  
Alloy 22 ◽  
Cyclic Potentiodynamic Polarization

AbstractA comprehensive matrix of 60 tests was designed to explore the effect of calcium chloride vs. sodium chloride and the ratio R of nitrate concentration over chloride concentration on the repassivation potential of Alloy 22. Tests were conducted using the cyclic potentiodynamic polarization (CPP) technique at 75°C and at 90°C. Results show that at a ratio R of 0.18 and higher nitrate was able to inhibit the crevice corrosion in Alloy 22 induced by chloride. Current results fail to show in a consistent way a different effect on the repassivation potential of Alloy 22 for calcium chloride solutions than for sodium chloride solutions

Molecular Transformations in DNA under the Influence of UV-radiation

2020 ◽  
Vol 04 ◽  
Author(s):  
Vigen G. Barkhudaryan ◽  
Gayane V. Ananyan ◽  
Nelli H. Karapetyan
Keyword(s):  
Uv Radiation ◽  
Uv Irradiation ◽  
Absorption Spectroscopy ◽  
Calf Thymus Dna ◽  
Dilute Solutions ◽  
Concentrated Solutions ◽  
Buffer Solution ◽  
Low Concentration ◽  
Calf Thymus ◽  
Dna Solutions

Background: The processes of destruction and crosslinking of macromolecules occur simultaneously under the influence of ultraviolet (UV) radiation in synthetic polymers, dry DNA and their concentrated solutions. Objective: The effect of UV radiation on calf thymus DNA in dilute solutions subjected to UV- irradiation was studied in this work. Method: The calf thymus DNA was studied in dilute solutions using viscometry, absorption spectroscopy and electrophoresis. Results: It was shown, that at a low concentration of DNA in the buffer solution ([DNA] = 85 μg / ml) under the influence of UV radiation, the processes of destruction of macromolecules and an increase in their flexibility predominate, which is accompanied by a gradual decrease in the viscosity of their solution. In addition, due to the low concentration of the solution, intramolecular crosslinking of macromolecules predominates, which also reduces their size and, consequently, the viscosity of the solution. Conclusion: It was concluded, that in dilute DNA solutions, due to the predominance of the processes of intramolecular crosslinking of macromolecules over intermolecular, only constant processes of decreasing the sizes of DNA macromolecules occur. As a result, its solubility remains virtually unchanged during UV irradiation. The described comments are also excellently confirmed by the results of absorption spectroscopy and electrophoresis

scholarly journals Nuclear matrix of HeLa S3 cells. Polypeptide composition during adenovirus infection and in phases of the cell cycle.

1977 ◽  
Vol 72 (1) ◽  
pp. 194-208 ◽  
Author(s):  
L D Hodge ◽  
P Mancini ◽  
F M Davis ◽  
P Heywood
Keyword(s):  
Cell Cycle ◽  
Molecular Weight ◽  
Nuclear Matrix ◽  
Apparent Molecular Weight ◽  
Molecular Weight Range ◽  
Weight Range ◽  
Molecular Weights ◽  
Liver Nuclei ◽  
Hela S3 ◽  
Biochemical Analyses

A subnuclear fraction has been isolated from HeLa S3 nuclei after treatment with high salt buffer, deoxyribonuclease, and dithiothreitol. This fraction retains the approximate size and shape of nuclei and resembles the nuclear matrix recently isolated from rat liver nuclei. Ultrastructural and biochemical analyses indicate that this structure consists of nonmembranous elements as well as some membranous elements. Its chemical composition is 87% protein, 12% phospholipid, 1% DNA, and 0.1% RNA by weight. The protein constituents are resolved in SDS-polyacrylamide slab gels into 30-35 distinguishable bands in the apparent molecular weight range of 14,000 - 200,000 with major peptides at 14,000 - 18,000 and 45,000 - 75,000. Analysis of newly synthesized polypeptides by cylindrical gel electrophoresis reveals another cluster in the 90,000-130,000 molecular weight range. Infection with adenovirus results in an altered polypeptide profile. Additional polypeptides with apparent molecular weights of 21,000, 23,000, and 92,000 become major components by 22 h after infection. Concomitantly, some peptides in the 45,000-75,000 mol wt range become less prominent. In synchronized cells the relative staining capacity of the six bands in the 45,000-75,000 mol wt range changes during the cell cycle. Synthesis of at least some matrix polypeptides occures in all phases of the cell cycle, although there is decreased synthesis in late S/G2. In the absence of protein synthesis after cell division, at least some polypeptides in the 45,000-75,000 mol wt range survive nuclear dispersal and subsequent reformation during mitosis. The possible significance of this subnuclear structure with regard to structure-function relationships within the nucleus during virus replication and during the life cycle of the cell is discussed.

scholarly journals The mechanism of in vitro clot lysis induced by vascular plasminogen activator

Blood ◽  
1984 ◽  
Vol 63 (6) ◽  
pp. 1331-1337 ◽  
Author(s):  
C Tran-Thang ◽  
EK Kruithof ◽  
F Bachmann
Keyword(s):  
Plasminogen Activator ◽  
Whole Blood ◽  
Apparent Molecular Weight ◽  
Clot Lysis ◽  
Initial Concentration ◽  
Low Concentrations ◽  
Sds Page ◽  
Tissue Plasminogen ◽  
Low Rate

Abstract The contribution of vascular plasminogen activator (v-PA) to the lysis of whole blood and plasma clots was investigated. v-PA released into the circulation after infusion of deamino-D-arginine vasopressin (DDAVP) was shown to bind quantitatively to plasma clots. Its apparent molecular weight, determined by the SDS-PAGE fibrin-agarose underlay method, was approximately 68,000 daltons, and its activity was quenched by antibodies against human tissue plasminogen activator (t-PA). Clots prepared from post-DDAVP plasma or post-DDAVP whole blood, rich in v- PA, did not lyse when incubated in imidazole buffer or normal plasma, as determined by the release of 125I from radiolabeled clots. However, clots made of v-PA-poor plasma or whole blood, incubated in v-PA-rich plasma, underwent substantial lysis. The concentration of PA in clots incubated in v-PA-rich plasma progressively increased in relation to the initial concentration of v-PA in the surrounding plasma. The results suggest that, at low concentrations of circulating v-PA, a hemostatic plug will lyse at a very low rate. However, when the v-PA concentration in the clot environment is increased, v-PA will accumulate progressively onto fibrin and induce thrombolysis.

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