Antibacterial catechol-based hyaluronic acid, chitosan and poly (N-vinyl pyrrolidone) coatings onto Ti6Al4V surfaces for application as biomedical implant

2021 ◽  
Author(s):  
Jon Andrade del Olmo ◽  
Leyre Pérez-Álvarez ◽  
Miguel Ángel Pacha-Olivenza ◽  
Leire Ruiz-Rubio ◽  
Oihane Gartziandia ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Vinyl Pyrrolidone ◽  
Biomedical Implant

A comparative study of dissolving hyaluronic acid microneedles with trehalose and poly(vinyl pyrrolidone) for efficient peptide drug delivery

2018 ◽  
Vol 6 (10) ◽  
pp. 2566-2570 ◽  
Author(s):  
Hong Kee Kim ◽  
Soo Hyeon Lee ◽  
Boo Yong Lee ◽  
Sung Jin Kim ◽  
Chang Yub Sung ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Hyaluronic Acid ◽  
Comparative Study ◽  
Vinyl Pyrrolidone ◽  
Peptide Drug ◽  
Pharmacokinetic Properties ◽  
Poly Vinyl Pyrrolidone

We studied the role of the additives trehalose and poly(vinyl pyrrolidone) in the physical and pharmacokinetic properties of peptide drug incorporated microneedles.

scholarly journals Effect on rabbits’ intraocular structure by cross-linked hyaluronic formations as vitreous substitute

2019 ◽  
Author(s):  
Yan Gong ◽  
Kai Chen ◽  
Yue Wu ◽  
Xiaohong Guo ◽  
Tao Zhang
Keyword(s):  
Hyaluronic Acid ◽  
Intraocular Pressure ◽  
Uv Light ◽  
Vitreous Body ◽  
Polymer Materials ◽  
Vinyl Pyrrolidone ◽  
Synthetic Hydrogel ◽  
Vitreous Substitutes ◽  
Acid Test

Abstract Purpose: To observe the effects of cross-linked hyaluronic hydrogel on retina struct and intraocular biocompatibility in rabbits. Methods: the polymer-derived hyaluronic acid which was formed by UV light cross-linked with N-vinyl-pyrrolidone. Free hyaluronic acid levels were detected by spectrophotometric method. Vitrectomy was then performed in the rabbits, and then cross-linked hyaluronic acid hydrogels of different concentrations were injected. Intraocular pressure measurements, cornea check-up, and B-ultrasound examination were performed during the follow-up period. After six weeks’ follow-up, the rabbits were sacrificed, and both eyes were removed. The eyeballs were fixed for HE staining, and the polymer materials were observed under electron microscopy. Results: The synthetic hydrogel present a transparent substance with a refractive index similar to that of the human vitreous body, which also had sufficient viscosity and elasticity for intraocular usage by rheological measurements. The results of the free hyaluronic acid test showed that the hydrogel had little degrade within one month. The results of the histology, intraocular pressure, B-ultrasound and retinal ultrastructure suggested that cross-linked hyaluronic acid hydrogel had superior tissue biocompatibility intraocular for six weeks. Conclusions: Hyaluronic acid-based cross-linked biopolymers had good biocompatibility in rabbit, which also shown promising potential as vitreous substitutes in clinical practice.

scholarly journals The substantiation of the choice of a gel former for developing the gel composition with hyaluronic acid and decametoxin

2021 ◽  
pp. 10-14
Author(s):  
G. Melnyik ◽  
T. Yarnykh ◽  
M. Buryak
Keyword(s):  
Hyaluronic Acid ◽  
Chronic Wounds ◽  
Corn Starch ◽  
Experimental Studies ◽  
Statistical Processing ◽  
Modern Medicine ◽  
Pathological Process ◽  
Vinyl Pyrrolidone ◽  
Gelling Agent ◽  
Mechanical Parameters

Topicality. Bedsores are an urgent problem of modern medicine both at the outpatient and inpatient stage. For the treatment of infected bedsores it is advisable to use drugs that have a complex effect focused on various parts of the pathological process. For the treatment of chronic wounds and bedsores together with the inhibition of the growth of microorganisms the drug must provide the optimal conditions for the growth of granulation, have a reparative and anti-inflammatory effect. Aim. To experimentally substantiate the composition of the gel base with hyaluronic acid and decamethoxine. Materials and methods. To select the structure-forming component in the gel base, the possibility of using “Ultrez 10 NF” carbomer, “Aristoflex AVC” (copolymer of acrylamidomethylpropanesulfonic acid and vinyl pyrrolidone) from Clariant Surfactants company, “Structure XL” (hydropropylated corn starch) as a gelling agent was studied. Organoleptic, physicochemical, structural and mechanical parameters of gel model samples were determined according to the methods of the State Pharmacopoeia of Ukraine. The statistical processing of the results was performed using the Statistica 6.0 program. Results and discussion. The choice of the optimal gelling agent was performed taking into account the results of the study of organoleptic, physicochemical, structural and mechanical parameters of gel model samples. The experimental studies conducted allowed to choose the optimal gelling agent – “Aristoflex AVC” in the concentration of 1 %. It is easily dispersed with water and does not require the addition of a neutralizer. It has been proven that the base selected has the optimal consumer, structural-mechanical, and physicochemical properties. Conclusions. Based on the organoleptic, physicochemical, structural-mechanical studies the composition of the gel base with hyaluronic acid and decamethoxine has been experimentally substantiated.

Healing of Circular Defects in the Rabbit Medial Meniscus Can Occur Spontaneously and Is not Improved by Intra-Articular Hyaluronic Acid

1996 ◽  
Vol 09 (02) ◽  
pp. 60-5 ◽  
Author(s):  
N. Hope ◽  
P. Ghosh ◽  
S. Collier
Keyword(s):  
Hyaluronic Acid ◽  
Medial Meniscus ◽  
Chondroitin Sulphate ◽  
Rabbit Model ◽  
Type Ii Collagen ◽  
Type Ii ◽  
Keratan Sulphate ◽  
Meniscal Healing ◽  
Meniscus Healing ◽  
Made In

SummaryThe aim of this study was to determine the effects of intra-articular hyaluronic acid on meniscal healing. Circular defects, 1.0 mm in diameter, were made in the anterior third of the medial meniscus in rabbits. In one joint, 0.4 ml hyaluronic acid (Healon®) was instilled, and in the contralateral (control) joint, 0.4 ml Ringer’s saline. Four rabbits were killed after four, eight and 12 weeks and the menisci examined histologically. By eight weeks most of the lesions had healed by filling with hyaline-like cartilage. Healing was not improved by hyaluronic acid treatment. The repair tissue stained strongly with alcian blue, and the presence of type II collagen, keratan sulphate, and chondroitin sulphate was demonstrated by immunohistochemical localisation. In contrast to the circular defects, longitudinal incisions made in the medial menisci of a further six rabbits did not show any healing after 12 weeks, indicating that the shape of the lesion largely determined the potential for healing.The effect of hyaluronic acid on meniscal healing was tested in a rabbit model. With one millimeter circular lesions in the medial meniscus, healing by filling with hyalinelike cartilage was not significantly affected by the application of hyaluronic acid intra-articularly at the time of surgery, compared to saline controls, as assessed histologically four, eight and 12 weeks after the operation.

A COMPARISON BETWEEN THE EXOPHTHALMOS INHIBITING EFFECTS OF SODIUM-D- AND SODIUM-L-THYROXINE IN GUINEA PIGS

1962 ◽  
Vol 41 (4) ◽  
pp. 619-624 ◽  
Author(s):  
Björn Tengroth ◽  
Uno Zackrisson
Keyword(s):  
Hyaluronic Acid ◽  
Pituitary Gland ◽  
Guinea Pigs ◽  
Anterior Lobe ◽  
Optical Isomers ◽  
Connective Tissues ◽  
Response Curves ◽  
Experimental Animals ◽  
Inhibiting Effect ◽  
Caloric Effect

ABSTRACT The general change in the connective tissues which occurs in animals with experimentally produced exophthalmos, consists in an increase in the amount of hyaluronic acid, which binds the water in the connective tissue. Many regard this process as a stimulation of the mucinous system in the connective tissues, and consider this an explanation of the phenomenon of exophthalmos. When the experimental animals are injected with thyroxine or thyroid extract, the reaction observed is opposite to that seen following the injection of the anterior lobe of the pituitary gland. In the former case, there is a reduction in the amount of hyaluronic acid and consequently a decrease in the water content in the connective tissues. In the experiments in question, Na-d-thyroxine and Na-l-thyroxine), in crystalline form, were tested for their inhibiting effect on the development of exophthalmos in experimental animals. The animals used were male albino guinea-pigs. An extract of the anterior lobe of the pituitary gland (TSH Organon)) was used to produce exophthalmos. In previous work (Tengroth 1961), it was shown, using an X-ray measuring technique, that d-thyroxine, despite its poor caloric effect, like l-thyroxine had an exophthalmos-inhibiting effect. When comparing the dose-response curves of the exophthalmos-inhibiting properties of both these optical isomers, it appears that d-thyroxine has an inhibiting effect which is significantly greater than that of l-thyroxine. The significance of this observation is discussed.

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