Degradation control of cellulose scaffold by Malaprade oxidation

2014 ◽  
Vol 1621 ◽  
pp. 191-196
Author(s):  
Wichchulada Konkumnerd ◽  
Suong-Hyu Hyon ◽  
Kazuaki Matsumura
Keyword(s):  
Amino Acid ◽  
Acid Solution ◽  
Room Temperature ◽  
Sodium Periodate ◽  
Periodate Oxidation ◽  
Oxidized Cellulose ◽  
Amino Groups ◽  
Amino Acid Solution ◽  
Before And After ◽  
Aldehyde Groups

ABSTRACTStudy on oxidizing cellulose scaffold to dialdehyde cellulose by sodium periodate (NaIO4) was carried out. Concentration of sodium periodate and the reaction time were effected for aldehyde introduction to cellulose scaffolds. Cellulose powder was dissolved in 1-butyl-3-methylimidazolium chloride, an ionic liquid, at 100°C and maintained at room temperature for 7 days, providing flexible cellulose scaffold. The cellulose scaffold was oxidized using periodate oxidation (Malaprade oxidation), which oxidizes carbohydrate by glycol cleavage to provide dialdehyde. Aldehyde groups introduced into cellulose were quantified by simple iodometry. Oxidized cellulose scaffold was degraded in the amino acid solution triggered by the reaction between aldehyde groups and amino groups. During immersion of the cellulose scaffolds in the amino acid solution, the mass loss of the scaffolds was evaluated by measuring of weight of oxidized cellulose scaffold before and after degradation.

scholarly journals Chemical Binding of Chitosan and Chitosan Nanoparticles onto Oxidized Cellulose

2015 ◽  
Vol 10 (2) ◽  
pp. 155892501501000 ◽  
Author(s):  
Olivera Sauperl ◽  
Mirjana Kostic ◽  
Jovana Milanovic ◽  
Lidija Fras Zemljic
Keyword(s):  
Chitosan Nanoparticles ◽  
Gravimetric Method ◽  
Fiber Surface ◽  
Oxidized Cellulose ◽  
Amino Groups ◽  
Before And After ◽  
The Difference ◽  
The Stability ◽  
Aldehyde Groups ◽  
The Masses

The aim of this study was to analyze binding of chitosan and chitosan nanoparticles onto cellulose via oxidized cellulose. The ability of chitosan and chitosan nanoparticles to be adsorbed onto surfaces was determined by the use of the XPS spectroscopy which provided information about chemical composition of the fiber surface. On the other hand, the gravimetric method was also used by which the amount of chitosan and chitosan nanoparticles bounded onto surface was calculated based on the difference in masses before and after functionalization. The most important was to study the influence of aldehyde groups on the stability of chitosan binding onto cellulose. Thus, desorption of chitosan/chitosan nanoparticles from the fiber surfaces was evaluated by the presence of total nitrogen (TN) in desorption bath as well as by polyelectrolyte titrations. Together with these two methods, desorption was evaluated also by gravimetric method, where the extent of desorption was evaluated on the basis of the differences in the masses of fibers before and after desorption. It is concluded that the chitosan and chitosan nanoparticles are more efficiently bounded onto oxidized cellulose in comparison with the non-oxidized (reference) ones. Despite the binding of the positively-charged amino groups with the negative groups of cellulose and consequently smaller amount of available/residual protonated amino groups that are responsible for bioactivity, such functionalized fibers are still specifically antimicrobial.

Intravenous Alimentation and Insensible Water Loss in Low-Birth- Weight Infants

PEDIATRICS ◽  
1979 ◽  
Vol 63 (4) ◽  
pp. 543-546
Author(s):  
Keith H. Marks ◽  
Timothy P. Farrell ◽  
Zvi Friedman ◽  
M. Jeffrey Maisels
Keyword(s):  
Amino Acid ◽  
Acid Solution ◽  
Water Loss ◽  
Caloric Intake ◽  
Constant Infusion ◽  
Fat Emulsion ◽  
Low Birth Weight Infants ◽  
Amino Acid Solution ◽  
Intravenous Fat Emulsion ◽  
Multiple Measurements

Insensible water loss (IWL) was measured in six premature infants, betWeen 4 and 21 days of age, by continuous weight monitoring on an electronic balance inside an incubator. Multiple measurements of IWL were made during the sequential infusion of 10% dextrose in 0.225% NaCl, 10% dextrose-amino acid solution, or 10% dextrose-amino acid and a commercial intravenous fat emulsion. Each solution was administered for three hours by constant infusion through a scalp vein needle. The order of the infusion was random and a 30-to 60-minute infusion with 5% dextrose water was given between each solution. During the infusion of 10% dextrose in 0.225% NaCl and 10% dextrose + amino acid solution, IWL was 1.0 ± 0.8 gm/kg/ hr and 1.1 ± 0.8 gm/kg/hr, respectively. In contrast, IWL increased significantly to 1.6 ± 0.7 gni/kg/hr when additional calories were given using the 10% dextrose-amino acid with the intravenous fat emulsion (P < .005). There was a positive correlation between caloric intake and IWL. These data suggest that parenteral nutrition solutions with intravenous fat emulsion are rapidly metabolized and the increase in IWL is probably secondary to an increase in thermogenesis.

Effect of Balanced Amino Acid Solution on Protein Metabolism after Surgery

1990 ◽  
Vol 17 (2) ◽  
pp. 100-103
Author(s):  
J. Figueras ◽  
E. Ramos ◽  
J.M. Llop ◽  
N. San-Juan ◽  
J. Marti
Keyword(s):  
Amino Acid ◽  
Acid Solution ◽  
Protein Metabolism ◽  
Amino Acid Solution

Effects of plasma amino acid and hormone levels on renal hemodynamics in humans

1988 ◽  
Vol 255 (3) ◽  
pp. F444-F449 ◽  
Author(s):  
P. Castellino ◽  
C. Giordano ◽  
A. Perna ◽  
R. A. DeFronzo
Keyword(s):  
Growth Hormone ◽  
Amino Acid ◽  
Acid Solution ◽  
Growth Hormone Secretion ◽  
Renal Hemodynamics ◽  
Time Sequence ◽  
Plasma Amino Acid ◽  
Base Line ◽  
Amino Acid Solution ◽  
Hormone Levels

The effect of plasma amino acid and hormone (insulin, glucagon, and growth hormone) levels on renal hemodynamics was studied in 18 healthy subjects. The following four protocols were employed: study 1, a balanced amino acid solution was infused for 3 h to increase plasma amino acid concentrations two to three times base line; study 2, the same amino acid solution was infused with somatostatin (SRIF) and infusions of insulin, glucagon, and growth hormone were concomitantly administered to replace the time sequence of increase in peripheral concentrations of these hormones as observed during study 1; study 3, the same amino acid infusion was administered with SRIF plus infusions of insulin, glucagon, and growth hormone to maintain plasma hormone concentrations constant at the basal level; study 4, SRIF was infused with insulin, glucagon, and growth hormone to reproduce the time sequence of increase of these hormones as observed in study 1; amino acids were not infused in this study. During study 1, glomerular filtration rate (GFR) and renal plasma flow (RPF) rose by 19 and 21%, respectively. During study 2 both the time sequence of and magnitude of rise in GFR and in RPF were similar to the changes observed during study 1. In studies 3 and 4 neither RPF nor GFR changed significantly from base line. These results indicate that 1) hyperaminoacidemia stimulates insulin/glucagon/growth hormone secretion and causes a modest rise in GFR and RPF; and 2) if hyperaminoacidemia is created while maintaining basal hormone levels constant or if plasma insulin/glucagon/growth hormone levels are increased while maintaining the plasma amino acid concentration at basal levels, neither RPF nor GFR rise.(ABSTRACT TRUNCATED AT 250 WORDS)

Therapy of myocardial infarction with metabolic agents

1986 ◽  
Vol 67 (5) ◽  
pp. 325-328
Author(s):  
A. E. Vtorov ◽  
L. A. Leshchinsky ◽  
L. T. Pimenov
Keyword(s):  
Myocardial Infarction ◽  
Amino Acid ◽  
Connective Tissue ◽  
Acid Solution ◽  
Anabolic Steroid ◽  
Amino Acid Solution ◽  
Complex Therapy ◽  
Hospital Rehabilitation ◽  
Tissue Metabolites

The aim of the present work was to study in dynamics the concentration of connective tissue metabolites (free and peptide-bound oxyproline) in patients with myocardial infarction at different stages of in-hospital rehabilitation when using metabolic agents as part of complex therapy: free crystalline amino acid solution - alvesin-nova (GDR) in combination with the anabolic steroid retabolol.

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