Development of a Chitosan-Vaseline Gauze Dressing with Wound-Healing Properties in Murine Models

Spiroconjugated 1,2,3-triazolo[5,1-b]1,3,4-thiadiazine stimulates functional activity of fibroblasts under skin injury regeneration

Background and purpose

One of the most important mechanisms of tissue regeneration is the high functional activity of cells, including proliferation. Currently, there are practically no effective skin cell activators on the pharmaceutical market. The purpose of this work was to demonstrate the stimulating effect of spiroconjugated 1,2,3-triazolo[5,1-b]1,3,4-thiadiazine (STT) on the functional activity of fibroblasts.

Experimental approach

STT containing ointment for dermal application was made. To assess in vivo effect of the STT a linear wound model in rats was tested. A combination of histological techniques and mechanical testing was employed to estimate the stimulating effect of STT on the functional activity of fibroblasts.

Findings/Results

The STT significantly increased the number of fibroblasts as well as the density and order of produced collagen fibers in the dermis during the wound healing process. As a result, a tissue was formed at the site of damage with the structure corresponding to normal skin. In addition, skin functions were restored, in particular mechanically.

Conclusion and implications

The results suggested the stimulating effect of the STT on fibroblast activity and demonstrated its potential for skin regeneration.

Current status and progress in research on dressing management for diabetic foot ulcer

Diabetic foot ulcer (DFU) is a major complication of diabetes and is associated with a high risk of lower limb amputation and mortality. During their lifetime, 19%-34% of patients with diabetes can develop DFU. It is estimated that 61% of DFU become infected and 15% of those with DFU require amputation. Furthermore, developing a DFU increases the risk of mortality by 50%-68% at 5 years, higher than some cancers. Current standard management of DFU includes surgical debridement, the use of topical dressings and wound decompression, vascular assessment, and glycemic control. Among these methods, local treatment with dressings builds a protective physical barrier, maintains a moist environment, and drains the exudate from DFU wounds. This review summarizes the development, pathophysiology, and healing mechanisms of DFU. The latest research progress and the main application of dressings in laboratory and clinical stage are also summarized. The dressings discussed in this review include traditional dressings (gauze, oil yarn, traditional Chinese medicine, and others), basic dressings (hydrogel, hydrocolloid, sponge, foam, film agents, and others), bacteriostatic dressings, composite dressings (collagen, nanomaterials, chitosan dressings, and others), bioactive dressings (scaffold dressings with stem cells, decellularized wound matrix, autologous platelet enrichment plasma, and others), and dressings that use modern technology (3D bioprinting, photothermal effects, bioelectric dressings, microneedle dressings, smart bandages, orthopedic prosthetics and regenerative medicine). The dressing management challenges and limitations are also summarized. The purpose of this review is to help readers understand the pathogenesis and healing mechanism of DFU, help physicians select dressings correctly, provide an updated overview of the potential of biomaterials and devices and their application in DFU management, and provide ideas for further exploration and development of dressings. Proper use of dressings can promote DFU healing, reduce the cost of treating DFU, and reduce patient pain.

Investigation of miscibiliy and physicochemical properties of synthetic polypeptide with collagen blends and their wound healing characteristics

A suitable condition is needed to foster a rapid recovery of wounds, which is a dynamic and intricate process. The development and characterization of mats of plastic-like peptide polymer (PLP) with collagen for wound healing applications are reported in this work. Viscosity parameters such as the Huggins coefficient [KH], the intrinsic viscosity [η], α by Sun, ∆[η]m by Garcia ∆B and μ suggested by Chee, ∆K, and β advocated by Jiang and Han, recommend the miscibility of the polypeptide in solution phase. Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and X-ray diffraction (XRD) methods in a solid phase. Thermal characteristics using a differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA) showed higher stability for the blends than the pure polymers. The collagen and PLP blends showed exceptional in vitro cytocompatibility, and the in vivo wound-healing studies on the Sprague-Dawley rats demonstrated faster wound healing within two weeks compared to the cotton gauze-treated injuries. Therefore, these membranes can be a possible alternative for treating skin injuries.

Multifunctional hydrogel wound dressing with rapid on-demand degradation property based on aliphatic polycarbonate and chitosan

The multifunctional hydrogel dressings are effective strategy to treat chronic wounds of diabetes. In addition, the ability of selective degradation on demand to change dressings could provide better patient compliance. Here, an injectable, self-healing hydrogel with rapid degradability on-demand is designed to promote the healing of diabetes wounds. The block copolymer formed by aldehyde modified aliphatic cyclic carbonate monomer with polyethylene glycol (MBP) and chitosan (CS) were crosslinked through the Schiff base bond to obtain a hydrogel with excellent injectability and self-healing ability. Due to the presence of carbonate bonds in MBP, it showed the rapid on-demand degradation characteristics triggered by N-acetylcysteine (NAC). At the same time, gallic acid (GA) was loaded into the hydrogel, giving the hydrogel dressing antioxidant. In vivo and in vitro experiments showed that the hydrogel wound dressing possesses good natures, such as antibacterial, antioxidant, and friendly cell compatibility, which could promote wound healing. Overall, the multifunctional hydrogel wound dressings with rapid on-demand degradation characteristics are more practical for clinical applications.

Effects of Essential Oils on Scars and Wound Healing: A Systematic Review

Essential oils (EOs) have been considered as a potential alternative therapy for wound healing and scar reduction. The aim of this article was to provide a comprehensive review examining the effects of EOs on wound healing and scars. PubMed, Cochrane, Ovid, and Embase computerized searches were performed through June 2020. Two independent reviewers conducted data extraction, with search results reviewed by the senior author following the PRISMA protocol. Three manuscripts examining three different EO-containing topical agents were analyzed. Outcomes include healing rate, erythema, pain, pruritus, patient discomfort, physician satisfaction, percent wound reduction, wound/scar surface perimeter area, and qualitative dermatological evaluation. All articles concluded that the EO-containing topical agents resulted in either superior or noninferior outcomes in comparison with controls. Hypericum-Calendula oil obtained lower wound surface perimeter area. Erythema (p = 0.001) was significantly decreased by the peppermint EO-containing topical agent. Physicians also reported greater satisfaction (p < 0.001) in wound appearance with use of the peppermint EO-containing topical agent. A paucity of studies have examined EO use for wound healing and scar reduction. Treatment with EO-containing topical agents resulted in decreased erythema with increased physician satisfaction of wound appearance. Future studies should assess what level of purity is needed for improved results and which EO, or combination of EOs, is most beneficial.

Vaseline gauze packing for the treatment of acute hemorrhagic rectal ulcer: Two case reports

RATIONALE

Acute hemorrhagic rectal ulcer (AHRU) is a relatively rare condition characterized by sudden onset, painlessness, and massive hematochezia in patients with severe underlying conditions. When AHRU is encountered, they can often be successfully controlled endoscopically, though recurrent bleeding is common and an alternative treatment must be sought if initial endoscopic treatment fails. We report 2 cases of AHRU which were successfully treated with Vaseline gauze packing after the failure of endoscopic hemostasis.

PATIENT CONCERNS

The first patient was an 88-year-old female that visited our emergency department with hematochezia. She was immobilized because of a left pelvic bone fracture resulting from a slip-down. The initial endoscopy showed fresh blood in her rectum with diffuse ulceration near the dentate line but no active bleeding. However, Massive hematochezia has recurred during conservation. A second patient, an 86-year-old female, debilitated because of schizophrenia, dementia, and past subdural hemorrhage, visited our emergency department, also with massive hematochezia. Her initial endoscopy showed deep ulceration near the dentate line. After admission, she experienced massive hematochezia from an AHRU with an exposed vessel but endoscopic hemostasis failed to control bleeding.

DIAGNOSES

Both patients were diagnosed as AHRU based on the endoscopic findings.

INTERVENTIONS

In both cases, Vaseline gauze packing was performed for bleeding control.

OUTCOMES

After Vaseline gauze packing, no further bleeding occurred and follow-up endoscopy showed definitive improvement of ulcers.

LESSONS

Based on these cases, we suggest that Vaseline gauze packing may be the alternative treatment for the AHRU which is located near the dentate line when endoscopic hemostasis is difficult or failed. Although further research is needed, Vaseline gauze packing has several potential advantages for the treatment of AHRU, especially in cases involving critically ill elderly patients.

Repair of multiple hand defects with superficial circumflex iliac artery perforator flap

BACKGROUND

Reconstruction and repair of multiple defects in the hand is a combination of function, sensation and aesthetics. The reconstruction using the superficial circumflex iliac artery perforator flap has become popular, which overcomes the inherent shortcomings of traditional inguinal flaps by preserving the deep fascia. In this report, we present our experience in the design and clinical application of the superficial circumflex iliac artery perforator flap, which we used to repair multiple defects in the hand.

METHODS

From January 2015 to December 2020, 41 patients received free superficial circumflex iliac artery perforator flap to repair multiple hand defects. All flaps were carefully designed according to the hand defect including 21 single and 20 bilobed flaps. The area of ​​the donor area is 2.5 cm × 3.0cm∼8.0 cm × 6.5 cm. We followed up all patients regularly and completed standardized assessments of outcomes based on post-reconstruction hand function and esthetic scores.

RESULTS

41 cases of flaps survived completely.3 cases of vascular crisis was relieved after surgical exploration, 1 case of mild distal necrosis was healed after dressing change, 1 case of pigmentation happened. There were 41 patients, 27 males and 14 females, with an average age of 40.5 years (4 to 59 years old). The defects included 20 cases opisthenars and 21 cases palms. The wounds were irregular, with exposed or damaged tendons, nerves or bones. All flaps were followed for a mean of 10.5 months (3 to 15 months). The functional and esthetic outcomes were satisfactory for all flaps without complications such as hand spasms, adhesions and scar contractures CONCLUSION: The superficial circumflex iliac artery perforator flap's donor site was concealed, relatively stable perforators, easy dissection. Recipient site condition was good and acceptable for the patients. It is a significant choice for multiple hand defects.

The Fabrication of Docetaxel-Containing Emulsion for Drug Release Kinetics and Lipid Peroxidation

Docetaxel (DTX)-based formulation development is still confronted with significant challenges, due to its refractory solubility and side effects on normal tissues. Inspired by the application of the transdermal drug delivery model to topical treatment, we developed a biocompatible and slow-release DTX-containing emulsion via self-assembly prepared by a high-speed electric stirring method and optimized the formulation. The results of accelerated the emulsion stability experiment showed that the emulsion prepared at 10,000 rpm/min had a stability of 89.15 ± 2.05%. The ADME, skin irritation, skin toxicity and molecular interaction between DTX and excipients were predicted via Discovery Studio 2016 software. In addition, DTX addition in oil or water phases of the emulsion showed different release rates in vitro and ex vivo. The DTX release ex vivo of the DTX/O-containing emulsion and the DTX/W-containing emulsion were 45.07 ± 5.41% and 96.48 ± 4.54%, respectively. In vitro antioxidant assays and anti-lipid peroxidation models revealed the antioxidant potential of DTX. However, DTX-containing emulsions could maintain and even enhance the antioxidant effect, both scavenging free radicals in vitro and inhibiting the process of lipid peroxidation.

Preparation and in vitro biocompatibility of PBAT and chitosan composites for novel biodegradable cardiac occluders

The biodegradable composites were prepared by melt blending of chitosan (CS) and poly(butyleneadipate-co-terephthalate) (PBAT). By utilizing Fourier transformed infrared spectroscopy, scanning electron microscopy-energy dispersive spectroscopy, mechanical properties analysis, water contact angle measuring, differential scanning calorimetry, and thermogravimetric analysis, it was demonstrated that the CS of the PBAT-CS10 composite was relatively evenly dispersed in the PBAT matrix, the mechanical properties were significantly improved, the hydrophilicity was increased, the cold crystallization temperature was increased, and a good range of melt working temperature was obtained. The PBAT-CS10 composite was used to fabricate a cardiac occluder by fused deposition modeling of three-dimensional printing, and finite element analysis, and in vitro implantation testing proved the occluder’s mechanical support and sealing function under extreme boundary conditions. In vitro degradation experiments, neutral red uptake cytotoxicity assay, CCK-8 cell proliferation detection, immunofluorescence staining of the cytoskeleton, cell apoptosis detection, and reactive oxygen species assay were all performed on the composite, confirming that it and the occluder made of it could be hydrolyzed under physiological conditions and had no adverse effects on the cell membrane, lysosome membrane, cell proliferation, cell morphology, cell apoptosis, or ROS level, and had good biocompatibility.

Efficiency of Multifunctional Antibacterial Hydrogels for Chronic Wound Healing in Diabetes: A Comprehensive Review

Diabetic chronic wounds or amputation, which are complications of diabetes mellitus (DM), are a cause of great suffering for diabetics. In addition to the lack of oxygen, elevated reactive oxygen species (ROS) and reduced vascularization, microbial invasion is also a critical factor that induces non-healing chronic diabetic wounds, ie, wounds still remaining in the stage of inflammation, after which the wound tissue begins to age and becomes necrotic. To clear up the infection, alleviate the inflammation in the wound and prevent necrosis, many kinds of hydrogel have been fabricated to eliminate infections with pathogens. The unique properties of hydrogels make them ideally suited to wound dressings because they provide a moist environment for wound healing and act as a barrier against bacteria. This review article will mainly cover the recent developments and innovations of antibacterial hydrogels for diabetic chronic wound healing.

SF/PVP nanofiber wound dressings loaded with phlorizin: preparation, characterization, in vivo and in vitro evaluation

Electrospinning-based wound dressings have multiple functions such as antibacterial, anti-inflammatory, and therapeutic, and are important in skin wound care. Herein, we designed a phlorizin (PHL)-loaded silk protein/polyvinylpyrrolidone (SF/PVP) composite nanofibrous membrane, which can be used as multiple wound dressings. In particular, SF/PVP/PHL scaffolds have high porosity and mechanical properties, exhibiting suitable permeability and hydrophilicity. The SF/PVP/PHL scaffolds containing PHL also have excellent antibacterial and antioxidant activities. Furthermore, the nanofiber significantly accelerated the wound healing process in a full-thickness skin injury model by enhancing wound re-epithelialization and collagen deposition density, increasing the content of macrophage antigen (CD68), platelet-endothelial cell adhesion molecule (CD31), proliferating cell nuclear antigen (PCNA) and inhibiting the expression of α-smooth muscle actin (α-SMA) at the wound site. The mechanism may be related to the inhibition of activation of phosphatidylinositol 3-kinase/serine-threonine kinase/ target of rapamycin (PI3K/AKT/mTOR) signaling pathway to enhance autophagy. Therefore, SF/PVP/PHL nanofibers can ideally meet the various requirements of the wound healing process and are promising wound dressing candidates for future clinical applications.

Effects of Natural Brown Cotton Bleached Gauze on Wound Healing

Natural brown cotton has favorable antibacterial and antioxidant properties. In this study, we explored the effect of gauze made from natural brown cotton after scouring and bleaching on wound healing in rats. In this work, a control experiment was adopted. The control group used absorbent cotton gauze, and the experimental group utilized natural brown cotton bleached gauze. The materials were applied to rat models to explore the effects of the two dressings on wound healing. By analyzing the wound healing state of rats, calculating the healing rate, and combining the pathological HE staining, Masson staining, and CD31 immunohistochemical staining, the results showed that both gauzes have positive effects on the wound healing of the rats. Moreover, compared with the control group, the wound healing rate of rats in the experimental group increased by 14.81%, the number of inflammatory cells decreased by 12.93%, the number of new blood vessels increased by 6.88%, the growth rate of the granulation tissue area was 10.76%, the step-up rate of the area occupied by collagen was 33.71%, and the increase rate of optical density value was 10.00%. This study found that natural brown cotton bleached gauze has a better effect on wound healing than ordinary absorbent cotton gauze, and can be used as medical dressings.

Application and nursing key points of wet dressings on the intestinal stoma after enterostomy

Patients with severe intestinal injury caused by trauma and malignant intestinal diseases require an artificial anus to be established through enterostomy to replace the original perineal anus for defecation. Although enterostomy has brought a new way of defecation to patients, the nursing requirements for an intestinal stoma after enterostomy are high. If complications arise from improper postoperative wound care, the quality of life of patients will be seriously reduced, and the psychological burden will be aggravated. This study compared the nursing effect of wet dressings and traditional dry dressings on patients undergoing enterostomy. Results showed that compared to patients using dry dressings, patients who used wet dressings had significantly lower postoperative dressing change frequency and complication rate, less pain during dressing change, and shorter hospital stays and intestinal stoma incision healing time. This suggests that wet dressings can promote wound healing in patients with enterostomy. In addition, it was found that compared to patients using dry dressings, the postoperative sleep quality, mood score, and quality of life of patients using wet dressings were significantly better. Evaluation of patient care comfort and satisfaction revealed that patients who used wet dressings felt significantly more comfortable and satisfied with their care than those who used dry dressings. Therefore, this study argues that wet dressings can facilitate the wound healing of the intestinal stoma in patients with enterostomy more than dry dressings, and better alleviate the bad moods and improve the quality of life of patients. Wet dressing can be used as a preferred nursing method for patients undergoing enterostomy.

Effects of chitosan-collagen dressing on wound healing in vitro and in vivo assays

The present study was designed to fabricate a new chitosan-collagen sponge (CCS) for potential wound dressing applications. CCS was fabricated by a 3.0% chitosan mixture with a 1.0% type I collagen (7:3(w/w)) through freeze-drying. Then the dressing was prepared to evaluate its properties through a series of tests. The new-made dressing demonstrated its safety toward NIH3T3 cells. Furthermore, the CCS showed the significant surround inhibition zone than empty controls inoculated by E. coli and S. aureus. Moreover, the moisture rates of CCS were increased more rapidly than the collagen and blank sponge groups. The results revealed that the CCS had the characteristics of nontoxicity, biocompatibility, good antibacterial activity, and water retention. We used a full-thickness excisional wound healing model to evaluate the in vivo efficacy of the new dressing. The results showed remarkable healing at 14th day post-operation compared with injuries treated with collagen only as a negative control in addition to chitosan only. Our results suggest that the chitosan-collagen wound dressing were identified as a new promising candidate for further wound application.

Flexible electrical stimulation device with Chitosan-Vaseline® dressing accelerates wound healing in diabetes

The healing process of diabetic wounds is typically disordered and prolonged and requires both angiogenesis and epithelialization. Disruptions of the endogenous electric fields (EFs) may lead to disordered cell migration. Electrical stimulation (ES) that mimics endogenous EFs is a promising method in treating diabetic wounds; however, a microenvironment that facilitates cell migration and a convenient means that can be used to apply ES are also required. Chitosan-Vaseline® gauze (CVG) has been identified to facilitate wound healing; it also promotes moisture retention and immune regulation and has antibacterial activity. For this study, we created a wound dressing using CVG together with a flexible ES device and further evaluated its potential as a treatment for diabetic wounds. We found that high voltage monophasic pulsed current (HVMPC) promoted healing of diabetic wounds in vivo. In studies carried out in vitro, we found that HVMPC promoted the proliferation and migration of human umbilical vein endothelial cells (HUVECs) by activating PI3K/Akt and ERK1/2 signaling. Overall, we determined that the flexible ES-chitosan dressing may promoted healing of diabetic wounds by accelerating angiogenesis, enhancing epithelialization, and inhibiting scar formation. These findings provide support for the ongoing development of this multidisciplinary product for the care and treatment of diabetic wounds.