The Clinical Application of �Alginon�, or a Plasma Expander of Sodium Alginate at a Low and Limited Degree of Polymerization

The chain termini of polynucleotides formed by limited enzymic fragmentation of wheat embryo ribosomal RNA. Part 1. Studies of snake venom phosphodiesterase

Canadian Journal of Biochemistry ◽

10.1139/o68-013 ◽

1968 ◽

Vol 46 (1) ◽

pp. 81-92 ◽

Cited By ~ 15

Author(s):

B. D. McLennan ◽

B. G. Lane

Keyword(s):

Snake Venom ◽

Ribosomal Rna ◽

Sedimentation Rate ◽

Sharp Decrease ◽

Degree Of Polymerization ◽

Wheat Embryo ◽

Snake Venom Phosphodiesterase ◽

Endonucleolytic Cleavage ◽

Limited Degree ◽

Hydrolysis Of

Snake venom phosphodiesterase induces about fifteen exonucleolytic cleavages for each endonucleolytic cleavage during the first hour of hydrolysis of wheat embryo ribosomal RNA, under the conditions of hydrolysis used in this present investigation. The polynucleotide chains in the ribosomal RNA preparation have an average degree of polymerization in the neighborhood of 1300 nucleotide residues, and there is a mean of between 5 and 10 endonucleolytic breaks per chain during this first hour of phosphodiesterase-induced hydrolysis. The cleavages occur widely throughout most of the polynucleotide chains in the ribosomal RNA preparation, as judged by the sharp decrease in mean sedimentation rate which accompanies a limited degree (about 10%) of exonucleolysis of the RNA. Studies of phosphodiesterase-induced endonucleolysis of wheat embryo soluble RNA are reported, but because of the much lower initial degree of polymerization (about 80 nucleotide residues per polynucleotide chain), the results of endonucleolysis are less pronounced in terms of the proportional increment in chain termini and the proportional decrease of mean sedimentation rate. The endonucleolysis of RNA is discussed in terms of the minor nucleotide components in both ribosomal and soluble RNA, and particular reference is made to pseudouridylate which has been found in relatively high proportion among the chain termini after limited hydrolysis with venom phosphodiesterase.Purified venom phosphodiesterase preparations, devoid of ribonuclease or 5′-nucleotidase contamination, were found to convert nucleoside 2′(3′),5′-diphosphates to 5′-nucleotides under conditions which had virtually no effect on nucleoside 3′-phosphates or nucleoside 5′-phosphates. The possibility that this reaction may be catalyzed by the venom phosphodiesterase itself is discussed.

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Effect of the Addition of Alginate and/or Tetracycline on Brushite Cement Properties

Molecules ◽

10.3390/molecules26113272 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3272

Author(s):

Claudia Morilla ◽

Elianis Perdomo ◽

Ana Karla Hernández ◽

Ramcy Regalado ◽

Amisel Almirall ◽

...

Keyword(s):

Antimicrobial Activity ◽

Calcium Phosphate ◽

Cell Viability ◽

Sodium Alginate ◽

Clinical Application ◽

Bone Defect ◽

Dicalcium Phosphate ◽

Release System ◽

Calcium Phosphate Cements ◽

Compression Resistance

Calcium phosphate cements have the advantage that they can be prepared as a paste that sets in a few minutes and can be easily adapted to the shape of the bone defect, which facilitates its clinical application. In this research, six formulations of brushite (dicalcium phosphate dihydrated) cement were obtained and the effect of the addition of sodium alginate was analyzed, such as its capacity as a tetracycline release system. The samples that contain sodium alginate set in 4 or 5 min and showed a high percentage of injectability (93%). The cements exhibit compression resistance values between 1.6 and 2.6 MPa. The drug was released in a range between 12.6 and 13.2% after 7 days. The antimicrobial activity of all the cements containing antibiotics was proven. All samples reached values of cell viability above 70 percent. We also observed that the addition of the sodium alginate and tetracycline improved the cell viability.

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OSMOTIC PRESSURE, MOLECULAR WEIGHT, AND VISCOSITY OF SODIUM ALGINATE

Canadian Journal of Research ◽

10.1139/cjr50b-016 ◽

1950 ◽

Vol 28b (3) ◽

pp. 105-113 ◽

Cited By ~ 47

Author(s):

F. G. Donnan ◽

R. C. Rose

Keyword(s):

Molecular Weight ◽

Sodium Chloride ◽

Osmotic Pressure ◽

Sodium Alginate ◽

Intrinsic Viscosity ◽

Degree Of Polymerization ◽

Low Concentrations

This work shows how the molecular weight of sodium alginate can be determined by measuring the values of the osmotic pressure, P, in the presence of low concentrations of sodium chloride, and extrapolation of P/C to C = 0, where C is the concentration of sodium alginate. For different samples of sodium alginate the slope of the curve P/C against C was independent of the molecular weight. Molecular weight values from 48,000 to 186,000 were obtained. The intrinsic viscosity of the different samples were linearly related to the degree of polymerization.

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