جستجوی مقالات مرتبط با کلیدواژه "زخم پوش" در نشریات گروه "پزشکی"

Bacterial nanocellulose as a natural hydrogel with unique properties such as high biocompatibility, and non-toxicity has been investigated as a modern dressing in recent years. Accordingly, this research aimed to improve the physical and chemical properties of this biopolymer for biomedical uses by eco-printing clove plant on bacterial cellulose.

For this purpose, the purified layers of bacterial nanocellulose were printed using different amounts of clove in an eco-print method, and consequently, the properties were investigated with ATR-FTIR, XRD, FEESEM, hydrophilicity, and antibacterial activity tests.

The characterization tests confirmed the chemical nature, crystal structure and nanofibrous substrate of bacterial cellulose. Also, the eco-print process did not have a negative effect on the surface hydrophilic properties of the finished samples, and in addition, the water absorption capacity of the sample treated with 10 grams of clove plant was increased by two times compared to the untreated sample. Additionally, all the samples showed antibacterial properties against two Gram-negative (Escherichia coli) and positive (Staphylococcus aureus) bacteria, while increasing the amount of clove active substance on the samples intensified the antimicrobial properties of the layers. Accordingly, the treated samples with 10 gr of clove resulted in the formation of a 30-mm diameter inhibition zone for both bacteria mentioned above.

Based on the findings of this research, it can be concluded that the bacterial nanocellulose treated with clove plant has a high capacity as a modern environmentally friendly wound dressing.

Wound dressing materials allocate a great portion of skin and draught maintenance in the global medical market.  In previous times the conventional dressing materials as natural and synthesized bondage, Cotton and gas were used for caring of skin wounds. Nowadays the production of modern wound dressing of higher restorative capabilities has attracted the attentions. These modern wound dressing can precipitate the re-epithelization, collagen synthesis and angiogenesis. These modern wound dressing materials can reduce the PH and perform as a barrier to bacterial penetration. There are several methods available for production of fibers and nanofibers. Between these methods electrospinning has attracted much interests. By this procedure it is possible to produce composite fibers and porous mats. The cells can penetrate to these pores and grow appropriately. The manufactured fibers usually have proper uniformity and the dimensions can vary from several nanometers to micrometers. These fibers can be used in different applications such as the filters, the fortifiers, the scaffolds and the wound dressing materials. The biocompatible materials are among the best choices for fabrication of the wound dressing, They can provide the necessary condition for growth of derma and epidermal layers. The multi-polymers Mat fibers have been used for tissue engineering applications, as they have the capability of the simulation of the extracellular Matrix. Drug addition to these scaffolds can enhance the function of this system and improve the restoration capabilities.  The electrospun wound dressing materials facilitate the tissue growth. The electrospun nano-fibers have similar structures to that of the skin and have higher compatibility with blood. They make the wound and tissue restoration possible. In this research the production of two layers wound dressing materials has been conducted by the electrospinning Method. The downward layers of these wound dressing materials have been manufactured from polyvinyl alcohol. Polyvinyl alcohol is a synthetic polymer which has proper electrospinning properties, and therefore it can be used for nanofibers production. The fibers have high tensile strength and an appropriate flexibility. This material is one of the oldest and most common materials that have been utilized for drug delivery systems, wound dressing and wound maintenance, contact lens and artificial limbs. This polymer is biocompatible, and due to the hydroxyl groups, it has reasonable water absorption. Also for infection inhibition vancomycin drug has been loaded in this layer.

Many different wound dressing fabrication methods have been used for many years. Among these techniques, electrospinning has attracted a lot of attention. This simple and cost-effective method produces nano and micro fibers substrates which simulate extracellular matrixes and provide a suitable porous structure for cell adhesion and proliferation. In this study, electrospinning was used for the fabrication of two-layer wound dressing, consisted from chitosan and poly (lactide-co-glycolide) acid (PLGA) as the first layer and polyvinyl alcohol (PVA) and vancomycin as the second layer. For the first layer electrospinning, the solution of chitosan, poly-lactic co-glycolic acid has been provided and transmitted to 5 ml syringe and located in the place.  the syringe tip attached to the electrical current source and the electrospun fibers were collected it on a aluminum foil covered collector. The ejection action was performed by the flow rate of 2 ml per hour and the electrospun fibers were manufactured on a 50 mm diameter collector.  In this research, the distance between the nozzle and the collector was 120mm and the rotating speed of the collector was 16 RPM. The device voltage was set at 15 kilovolts. For electrospinning of the second layer the solution of polyvinyl alcohol and vancomycin was provided and transmitted into 5ml syringe, just like previous steps.  The injection process was performed by the volume rate of 1 ml per hour and electrospun fibers were gathered on the 15 mm diameter collector.  In this level, the distance between the nozzle and the Collector was 200mm, the rotating speed was 10 RPM and the device voltage was set at 15 kilovolts. For cross-linking, the samples were located on the vapor of glutaraldehyde and HCL by the molar ratio of 1:10 for 12 hours.

Electrospun two layer wound dressing microstructure was evaluated by scanning electron microscopy (SEM). It was observed that both layers have homogenous bead free interconnected porous structures. Image measurement software revealed that fiber diameters ranged from 0.2 to 1.2 micrometer, which can provide a proper substrate for cell proliferation. Functional groups of raw materials and chemical bonding between layers were assessed by FTIR analysis. In order to evaluate layers absorption capacity, they were soaked in PBS solution for 24 hours. They showed about 112.4±10.2 % PBS absorption after 24 hours. So they can absorb wound secretions and keep the wound environment dry. Biodegradation tests showed that 32.7 % of these two layer wound dressing was degraded after 3-weeks immersion in PBS solution. Drug release tests demonstrated a burst release of vancomycin in the first hours which followed by decreasing releasing rates. These releasing manner lowered infection appearance in the wound site. Antibacterial activity is an important factor in wound dressing and the co-existence of chitosan and vancomycin provided approximately 98.72 % bacterial reduction in the antibacterial assay. Although the antibacterial test showed a significant reduction in bacterial growth, the MTT test showed that these scaffolds are biocompatible and provide a favorable environment for cell attachment and proliferation.

The images of the microstructure electrospun substrates depicted that electrospun two-layer polyvinyl alcohol vancomycin and poly lactic co-glycolic acid chitosan substrate has a porous fiber structure, in a way that these pores are interconnected.  The fibers of two layers have no beads and they have relatively homogeneous distribution. The water absorption of these scaffolds showed suitable inflation strength in 24-hours of submerge in phosphate buffer saline.  Also the degradation capability of the samples demonstrated the approximately 32% degradation of the structure in 3-weeks.  It illustrated convenient degradation time of wound dressing and it is in good correspondence with previous researchers. Drug delivery assessment of vancomycin from these samples was relatively explosive in the initial hours.  But it reached an equilibrium state in some hours.  The initial explosive delivery can lead to eradication of the initial bacteria and it is a key factor in wound dressing applications. The antibacterial assessment of their structure demonstrated high antibacterial capabilities due to the existence of chitosan and vancomycin in these scaffolds. About 98% of the batteries at the dose of 10 mg/lit were perished.  Also the cellular viability investigation for these scaffolds proved non-toxicity and biocompatibility. The cultured cells on the scaffolds had normal morphology. According to acquired results in this study, it seems that these two layer electrospinning substrates can be useful for wound healing.

Severe hemorrhage is the leading cause of death in comilitary and civilian trauma. Approximately half of road crash fatalities occur due to severe hemorrhage before hospital arrival. In severe cases of bleeding, the use of agents that accelerate blood coagulation (hemostatic agents) is required. The aim of this study was to review on the hemostatic agents and products, from research to commercial stages, and categorizing them based on the physiology of hemostasis. Moreover, the applications and adverse effects of each category have been reviewed and compared; it can be an important step towards optimal clinical application of products and novel original reasearch design continuing the previous studies.

Literature search was conducted in scientific databases of PubMed, Scopus, Science Direct, SID, Magiran and IranMedex without filtering release date, by combining related keywords including hemostatic agents, bleeding, dressings and trauma. The abstracts were screened by two reaserchers independently to select the appropriate studies.

In this study, according to the basics of blood coagulation, the hemostatic agents and products were classified into five groups based on the mechanism of action including: (1) coagulants and procoagulants, (2) the concentrators of coagvlant factors, (3) mechanical cougulaton substrates, (4) physiologic coagulants and (5) chemical coagulants. The mechanism of action, applications, and side effects have been compared in each category.

Each hemostatic product can be more effective in special situations, in military and civilian trauma, due to their potency and mechanisms of action.

Among various carrier materials capable of drug controlled-release, silica xerogels have been found to be noteworthy for loading and sustaining drug release. These silica xerogels were synthesized through sol-gel technology using Tetraethylortosilicate (TEOS) as a silica precursor.

This study was an experimental basic research, which aimed to characterize the effect of adding chitosan to silica xerogels on Morphology, surface area and topography as well as mechanical behavior of the hybrid films. Furthermore, the lidocaine hydrochloride was incorporated on to the hybrid chitosan-silica xerogels and drug release behavior of the hybrid xerogels was evaluated and compared with pure silica xerogels. In addition, the covalent bond between chitosan chains and silica network was verified by FTIR; MTT assay was performed to evaluate cytotoxicity of the final system.

The release profile of hybrid xerogels showed biphasic mode of release and approximately 71 % accumulative release rate. Chitosan slightly decreased burst effect and release rate, but extended release period in comparison with silica xerogel. Moreover, blending of chitosan and TEOS enhanced tensile elongation and reduced the average pore size of TEOS-based xerogels.

In conclusion, this in vitro study showed that the sol–gel method is useful for entrapping lidocaine hydrochloride in the pores of xerogels and its controlled release. Likewise, blending of chitosan and TEOS improves tensile mechanical properties of resulted biocompatible films. Hence, the final organic-inorganic films are capable to be applied as a coating or thin films in biomedical applications.

One of the goals of medical science in current communities is wound healing in shorter time and with less side effects. The nettle extract in the presence of chitosanchr('39')s natural polymer can have antimicrobial and repairing properties. It also improves the recovery speed with less complications and less time.

For different tests, we produced a chitosan film with different percentages of 10%, 20%, 40% of nettle extract and a control sample without plant extracts. These tests include scanning electron microscopy (SEM), percentage of water absorption, antibacterial properties, percentage of inflation, degradability rate.

The sample with high percentage of plant extract had a higher porosity surface than other samples and could be considered as a suitable wound dressing. Using two gram positive bacteria (Staphylococcus aureus) and gram negative (Pseudomonas aeruginosa) from the body of patients in Taleghani Hospital of Tehran to evaluate the antimicrobial activity of the film containing nettle extract and chitosan was used. The results of Staphylococcus aureus bacteria are better than Pseudomonas aeruginosa. Results were calculated with Prism software.

A wound dressing should be capable of absorbing extra secretions from the wound, antibacterial, smoot cutting without damaging the wound , biodegradable. The results of this study indicate that the wound dressing prepared in this project can have the conditions of an ideal wound dressing.

Introdution: Wound healing is a complex and dynamic process, which requires to be prepared a suitable environment to promote healing process. Wound dressing is one of the most important external factors affecting the wound healing process. With the advancement in technology, more than 1000 types of modern wound dressings have been developed. Wound dressings are either based on natural materials or on the basis of synthetic and chemical materials. In addition to the protective and covering role, which modern wound dressings play, they have a chemical and physical interaction with wound bed addition. They carry antibiotics, drugs and nanoparticles and play an important role in maintaining moisture or hydration the wound; all of these factors can facilitate the wound healing process. In this study, the wound healing process and the properties of wound dressings were presented first and then the types of wound dressings and their applications were investigated. This study, with comprehensive information on the types of modern wound dressings and their advantages and drawbacks, will help a physician in the proper selection of an appropriate wound dressing.

The aim of this study was to assess the applied characteristics of wound covers containing nanoliposomic essential oil of ajwain, with suitable antimicrobial properties and lack of cytotoxicity. Liposomal formulations of the ajwain essential oil containing DSPE-PEG, cholesterol, span60 and SPC80 were prepared using a thin layer method. The rooting and spray methods on a cellulose fabric were used to produce skin wound cover. In addition to in vitro intracellular penetration and measurement of minimum inhibitory concentration of the product, textile characteristics, antimicrobial activity and 96 hours release of the essence in the wound cover were studied. Ethical Considerations: In this study, all principles of research ethics were considered. The loading efficiency of the liposomal formulation was more than 85%. The small particle dispersion index (PDI = 0.02) in the form of the PEGylated formulation indicates optimal dispersion of the particles which reduces the buildup of the drug in the cutaneous application. The standard AATCC microbial test showed inhibitory effect of the wound cover on bacteria, especially E. coli. Textile tests indicated acceptable properties of the produced wound cover, too. Altogether, this wound cover showed acceptable features in combating the two selected bacteria responsible for infectious skin ulcers.

Diabetes is one of the most common chronic diseases. Diabetes mellitus is a metabolic disorder in the metabolism of fats, carbohydrates and proteins in the body which were caused by the changes in insulin secretion in the body. Diabetes is malfunctioning in the body’s vessels. This research aimed to develop a wound dressing that causes the damaged vessels to be reconstructed and it can improve diabetic wounds as soon as possible. Methods and Materials: In the present study, Chitosan was selected as a biocompatible and biodegradable polymer to form a wound dressing. Moreover, different cross linkers including betaglycerphosphate (BGP), triple polyphosphate (TPP) and alginate (ALg) were added as a Chtoson compositematerial material. Wound dressing has been made from Chitosan with beta-glycerophosphate, tripolyphate and alginate. In the scanning electron microscopy test,the CS-AL sample had the best structure for the number of cavities and uniformity of cavities. In the water absorption test, CS-AL sample had the best water absorption among other samples (3854%).In the wound dressing airborne test, only CS-AL wound dressing was achieved the minimum air permeation value. In the test of degradibility, the CS-AL sample was 80% degraded after 14 days, which is the appropriate percentage for ulcers. In addition, the GSNO was loaded into this wound dressing. Based on the results of this graval test, we see a peak generated at 540 nm including the release of nitric oxide gas from GSNO powder and GSNO containing ulcer. Discussion and Conclusion: After performing scanning electron microscopy, air permeation testing, water absorption and degradability, the CS-ALg specimen has the best conditions for producing the final wound dressing, then the GSNO powder was added as a release agent for nitric oxide to the wound dressing and the release of gas Nitric oxide was evaluated from the wound dressing. The constructed wound dressing, releases the Nitric oxide gas successfully in regarding to our study results.

Production of skin dressings or substitutes is one of the most important tissue engineering fields. Since copper is an important agent in skin extracellular matrix synthesis, we investigated the effect of collagen-gelatin-bioglass scaffolds containing copper in accelerating the healing process of full-thickness skin wound in mouse model.
We used 12 mice with two identical skin wounds on their back (with 5 mm diameter, circular, and full-thickness), one wound as control, second dressed with collagen-gelatin-bioglass scaffold, and third dressed with collagen-gelatin-bioglass scaffold containing copper. After 14 days, the wound healing process was analyzed using both macroscopic and microscopic (after hematoxylin and eosin staining) methods.
Findings: The wound dressings had porous structure, and were biocompatible. They improved the healing process of full-thickness wound in mouse model. This process was statistically much better in the dressings comprising copper (P Since wounds dressed with collagen-gelatin-bioglass scaffold containing copper improved wound healing in animal models, it can be suggested as a new approach in design and synthesis of wound dressings for human.