Slow release iodine preparation and wound healing: in vitro effects consistent with lack of in vivo toxicity in human chronic wounds

Supramolecular Structure of the β-Cyclodextrin Metal-Organic Framework Optimizes Iodine Stability and Its Co-delivery with l-Menthol for Antibacterial Applications

The spread of upper respiratory tract (URT) infections harms people's health and causes social burdens. Developing targeted treatment strategies for URT infections that exhibit good biocompatibility, stability, and strong antimicrobial effects remains challenging. The dual antimicrobial and antiviral effects of iodine (I2) in combination with the cooling sensation of l-menthol in the respiratory tract can simultaneously alleviate URT inflammation symptoms. However, as both I2 and l-menthol are volatile, addressing stability issues is crucial. In this study, a potassium iodide β-cyclodextrin metal-organic framework [β-CD-POF(I)] with appropriate particle size was used to coload and deliver I2 and l-menthol. Primarily, β-CD-POF(I) was employed as the most efficient carrier to significantly enhance the stability of I2, surpassing any other known protection strategies in the pharmaceutical field (CD complexations, PVP conjugations, and cadexomer iodine). The mechanism underlying the improvement in stability of I2 by β-CD-POF(I) was investigated through scanning electron microscopy with energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and molecular docking. The results revealed that the key processes involved in improving stability were the inclusion of I2 by β-CD cavities in β-CD-POF(I) and the formation of polyiodide anion between iodine ions and I2. Furthermore, the potential of β-CD-POF(I) to load and deliver drugs was validated, and coloading of l-menthol and I2 demonstrated reliable stability. β-CD-POF(I) achieved a rate of URT deposition ≥95% in vitro, and the combined antibacterial effects of coloaded I2 and l-menthol was better than I2 or PVP-I alone, with no irritation noted following URT administration in rabbits. Therefore, the stable coloading of drugs by β-CD-POF(I), leading to enhanced antimicrobial effects, provides a new strategy for treating URT infections.

Management of soft tissues in patients with periprosthetic joint infection

BACKGROUND

Appropriate soft tissue management represents a critical step in treating periprosthetic joint infection (PJI). This review discusses relevant guidelines that surgeons should follow in the management of soft tissues in PJI treatment. BODY: It is imperative for arthroplasty surgeons to thoroughly debride and rebuild soft tissue with a good blood supply. Relevant guidelines that surgeons should follow rigorously include preoperative evaluation of soft tissue status and plan-making, adequate surgical area exposure, intraoperative removal of all necrotic and infected soft tissues, adequate coverage of soft tissue defects, timely postoperative assessment and management of soft tissues, wound management and proper rehabilitation.

CONCLUSION

Soft tissue management plays a critical role in the treatment of PJI. To improve the infection control rate and postoperative joint function, surgeons should be familiar with these general principles and rigorously practice them in PJI management.

Comparison of the Outcomes of Cadexomer Iodine and Povidone-Iodine Ointments in Wound Management

Background In this era of upcoming newer formulations of topical ointments in the market, selecting an appropriate topical ointment for managing ulcers is challenging with regards to granulation tissue promotion, ulcer size reduction, and decrease in the amount of discharge from the ulcer. This study compares the outcomes of two topical iodine formulations, namely, cadexomer iodine ointment (0.9%) and povidone-iodine ointment (5%), for the management of various types of ulcers. Methodology This prospective, interventional study was conducted in a tertiary care hospital. After screening, 40 patients with ulcers (venous, arterial, diabetic, traumatic, infective) were subjected to simple randomization based on computer-generated random numbers at a ratio of 1:1 for the application of cadexomer (n = 20) (Group A) and povidone-iodine ointment (n = 20) (Group B). Selected patients were subjected to broad-spectrum antibiotics on admission and then shifted to special antibiotics based on the culture and sensitivity report of the wound. The application of these two formulations was done in three settings, each lasting 48 hours. The efficacy of these two formulations was assessed based on the following three parameters: (a) the percentage of granulation tissue promotion, (b) wound size reduction, and (c) decline in wound discharge. The study groups were compared using an unpaired t-test, while the association among the study groups was performed using Fishers' test, Student's t-test, and chi-square test. P-values less than 0.05 were considered significant. Results Significant improvement (p < 0.05) in granulation tissue was observed with cadexomer ointment application compared to povidone-iodine ointment. Statistically significant reductions in ulcer size and discharge from ulcers were seen in both groups; however, clinically, cadexomer ointment was found to be more effective compared to povidone-iodine ointment in reducing ulcer size as well as in reducing the amount of discharge from ulcers. Conclusions Cadexomer iodine ointment proved to be better than povidone-iodine ointment in the management of ulcers regarding the percentage of granulation tissue promotion, ulcer size reduction, and decrease in the amount of discharge from ulcers.

Wound Antiseptics and European Guidelines for Antiseptic Application in Wound Treatment

Issues arising in wound healing are very common, and chronic wound infections affect approximately 1.5% of the population. The main substances used in wound washing, cleansing and treatment are antiseptics. Today, there are many compounds with a known antiseptic activity. Older antiseptics (e.g., boric acid, ethacridine lactate, potassium permanganate, hydrogen peroxide, iodoform, iodine and dyes) are not recommended for wound treatment due to a number of disadvantages. According to the newest guidelines of the Polish Society for Wound Treatment and the German Consensus on Wound Antisepsis, only the following antiseptics should be taken into account for wound treatment: octenidine (OCT), polihexanide (PHMB), povidone-iodine (PVP-I), sodium hypochlorite (NaOCl) and nanosilver. This article provides an overview of the five antiseptics mentioned above, their chemical properties, wound applications, side effects and safety.

Efficacy of topical cadexomer iodine treatment in chronic wounds: Systematic review and meta-analysis of comparative clinical trials

The aim of this study was to summarise the clinical evidence supporting almost 40 years of topical cadexomer iodine (CIOD) use in wound bed preparation by removing barriers to healing such as exudate, slough, bioburden, and infection and allowing chronic wound progression. A systematic review was conducted (Embase/PubMed, November 2020) to identify relevant comparative studies meeting inclusion criteria. Meta‐analyses were performed using a fixed‐effects (I² < 50%) or random‐effects model (I² ≥ 50%) depending on statistical heterogeneity. Dichotomous outcomes were reported as relative risk (RR) and continuous outcomes as mean difference (MD), with 95% confidence intervals. In total, 436 publications were identified of which 13 were comparative trials including outcomes of interest. Significant reductions in exudate, pus/debris, slough, bioburden, and infection were reported in chronic wounds treated with CIOD, compared with standard of care (SOC). Meta‐analyses highlighted the positive impact of CIOD on mean wound area reduction (MD = 2.35 cm², 95% CI = 0.34–4.36, P = .0219) after eight weeks treatment and overall wound healing events compared to SOC; wounds including venous leg ulcers, diabetic foot ulcers, and pressure ulcers treated with CIOD were more than twice as likely to heal than those receiving SOC (RR = 2.30, 95% CI = 1.54–3.45, P < .0001). This meta‐analysis demonstrates the efficacy of CIOD on chronic wounds through removal of barriers to healing. CIOD should be considered in wound bed preparation and treatment protocols.

The role of coordination compounds in virus research. Different approaches and trends

This article aims to provide an overview of the studies focused on using coordination compounds as antiviral agents against different types of viruses. We present various strategies so far used to this end. This article is divided into two sections. The first collects the series of designed antiviral drugs based on coordination compounds. This approach has been developed for many years, starting from the 70s with the discovery of cis-platin (cis-DDP). It has been mainly focused on studying the synergistic effect of a wide variety of new compounds obtained by combining metal ions with organic antiviral ligands. Then, we collect various strategies analyzing the coordination compounds interacting with viruses using different processes such as wrapping viruses, rapid detection of RNA or DNA virus, or nanocarriers. These recent and novel insights help to study viruses from other points of view, allowing to measure their physical and chemical properties. We also highlight a section in which the issue of viruses from a disinfection viewpoint is addressed, using coordination compounds as a tool able to control the release of antiviral and biocide agents. This is an emerging and promising field but this approach is actually little developed. We finally provide a section with a general conclusion and perspectives.

Agar-Iodine Transdermal Patches for Infected Diabetic Wounds

In the present work, we have tested the potency of iodine-loaded agar transdermal patches (5 mg/cm²) for the treatment of infected diabetic wounds in the Wistar rat model. The rats were treated with the newly developed agar-iodine-potassium iodide (KI)-glycerol (AKIG) patch along with two other commercial dressings Iodoflex and Tegaderm as controls. Animals that received treatment with AKIG patches and Iodoflex showed better infection containment as compared to that with Tegaderm-covered control and exhibited complete healing. The antimicrobial property of all the patches was tested on three bacterial species-Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa-found in infected wounds. P. aeruginosa exhibited the highest minimum inhibitory concentration and minimum bactericidal concentration values among the three bacterial species for all the patches. The patch showed values of tensile strength, elongation, water vapor transmission rate, and swelling in the range of 34 ± 5 MPa, 51% ± 5, 2700 ± 110 g/m²/day, and 250% ± 25, respectively, for the agar-KI-iodine patch. The release kinetics of iodine through the agar matrix was found to follow the first-order drug release kinetics.

Therapeutic compression materials and wound dressings for chronic venous insufficiency: A comprehensive review

Chronic venous insufficiency (CVI) is a common disorder worldwide. Related pathophysiological mechanisms reportedly involve venous pooling and reduced venous return, leading to heaviness, aching, itchiness, tiredness, varicosities, pigmentation, and even lower limb ulceration. Approaches adopted to manage CVI at various stages of clinical-etiology-anatomy-pathophysiology include compression therapy, pharmacological treatment, ultrasound treatment, surgery, electrical or wireless microcurrent stimulation, and pulsed electromagnetic treatment. Among these, polymer-based therapeutic compression materials and wound dressings play increasingly key roles in treating all stages of CVI because of their unique physical, mechanical, chemical, and biological functions. However, the characteristics, working mechanisms, and effectiveness of these CVI treatment materials are not comprehensively understood. The present systematic review examines the structures, properties, types, and applications of various polymer-based compression materials and wound dressings used in prophylaxis and treatment of CVI. Existing problems, limitations, and future trends of CVI treatment materials are also discussed. This review could contribute to the design and application of new functional polymer materials and dressings to enhance the efficiency of CVI treatments, thereby facilitating patients' self-care ability and long-term health improvement.

Cadexomer iodine effectively reduces bacterial biofilm in porcine wounds ex vivo and in vivo

Biofilms are prevalent in non-healing chronic wounds and implicated in delayed healing. Tolerance to antimicrobial treatments and the host's immune system leave clinicians with limited interventions against biofilm populations. It is therefore essential that effective treatments be rigorously tested and demonstrate an impact on biofilm across multiple experimental models to guide clinical investigations and protocols. Cadexomer iodine has previously been shown to be effective against biofilm in various in vitro models, against methicillin-resistant Staphylococcus aureus biofilm in mouse wounds, and clinically in diabetic foot ulcers complicated by biofilm. Similarities between porcine and human skin make the pig a favoured model for cutaneous wound studies. Two antiseptic dressings and a gauze control were assessed against mature biofilm grown on ex vivo pig skin and in a pig wound model. Significant reductions in biofilm were observed following treatment with cadexomer iodine across both biofilm models. In contrast, silver carboxymethylcellulose dressings had minimal impact on biofilm in the models, with similar results to the control in the ex vivo model. Microscopy and histopathology indicate that the depth of organisms in wound tissue may impact treatment effectiveness. Further work on the promising biofilm efficacy of cadexomer iodine is needed to determine optimal treatment durations against biofilm.

Improvement of Ulcerations in Treatment-Resistant Chronic Scarring in a Patient with Pyoderma Gangrenosum After Improving Vascular Insufficiency, Gently Removing Necrotic Debris, and Decreasing Wound Fluid

BACKGROUND Classical pyoderma gangrenosum is a rare, inflammatory, neutrophilic dermatosis that commonly presents with severe ulcerations on the lower extremities and is often misdiagnosed and mistreated. Delay in treatments can lead to worsening of the ulcerations and allows for multiple comorbid factors. Pyoderma gangrenosum is most commonly treated with immunosuppressants or anti-inflammatory agents and is often worsened by surgical procedures due to the presence of pathergy. In acute cases, a course of anti-inflammatory treatments works well in alleviating symptoms and reducing ulcerations and residual scarring. However, in chronic cases with the presence of severe scarring and necrotic ulcerations, the simple implementation of systemic immunosuppressants is frequently ineffective alone. Although not mentioned in most case reports on pyoderma gangrenosum, the chronicity of its inflammatory component can lead to necrosis and scarring and subsequent vascular insufficiency. CASE REPORT We present a severe case of chronic ulcerative pyoderma gangrenosum in a patient who had treatment-resistant ulcerations and cribriform edematous scarring with subsequent vascular insufficiency of the right lower extremity. This patient, while receiving topical clobetasol, had marked improvement in the healing of his ulcerations only after starting a novel course of cadexomer iodine, compression stockings, and pentoxifylline. CONCLUSIONS The efficacy of non-anti-inflammatory treatments indicates that chronic pyoderma gangrenosum with extensive scarring is commonly associated with the comorbid factors of vascular insufficiency, necrotic debris, and extensive wound fluid. In cases of ulcerations in chronic pyoderma gangrenosum that are resistant to anti-inflammatory treatments alone, one should identify and address other compounding factors that may inhibit wound healing.

Injectable Nanocurcumin-Formulated Chitosan-g-Pluronic Hydrogel Exhibiting a Great Potential for Burn Treatment

Burn wound healing is a complex multifactorial process that relies on coordinated signaling molecules to succeed. Curcumin is believed to be a potent antioxidant and anti-inflammatory agent; therefore, it can prevent the prolonged presence of oxygen free radicals which is a significant factor causing inhabitation of optimum healing process. This study describes an extension of study about the biofunctional nanocomposite hydrogel platform that was prepared by using curcumin and an amphiphilic chitosan-g-pluronic copolymer specialized in burn wound healing application. This formular (nCur-CP, nanocomposite hydrogel) was a free-flowing sol at ambient temperature and instantly converted into a nonflowing gel at body temperature. In addition, the storage study determined the great stability level of nCur-CP in long time using UV-Vis and DLS. Morphology and distribution of nCur in its nanocomposite hydrogels were observed by SEM and TEM, respectively. In vitro studies suggested that nCur-CP exhibited well fibroblast proliferation and ability in antimicrobacteria. Furthermore, second- and third-degree burn wound models were employed to evaluate the in vivo wound healing activity of the nCur-CP. In the second-degree wound model, the nanocomposite hydrogel group showed a higher regenerated collagen density and thicker epidermis layer formation. In third degree, the nCur-CP group also exhibited enhancement of wound closure. Besides, in both models, the nanocomposite material-treated groups showed higher collagen content, better granulation, and higher wound maturity. Histopathologic examination also implied that the nanocomposite hydrogel based on nanocurcumin and chitosan could enhance burn wound repair. In conclusion, the biocompatible and injectable nanocomposite scaffold might have great potential to apply for wound healing.

Antimicrobial peptide delivery: an emerging therapeutic for the treatment of burn and wounds

The management of wounds and burns is becoming difficult using conventional therapeutics available due to resistance development by microbes. Therefore, there is an utmost need to develop therapeutic alternatives to these agents. Antimicrobial peptides have emerged as a novel class of agents for the effective management of wounds and burns due to their potent nature along with minimal chances of resistance development against them. This article focuses on highlighting the importance of these antimicrobial peptides among the various therapeutic alternatives for burns and wounds. Further, effective delivery strategies for these agents that are being employed and investigated are reported along with an overview of the importance of these agents in the coming years.

Three-Dimensional Printing Antimicrobial and Radiopaque Constructs

Three-dimensional (3D) printing holds tremendous potential as a tool for patient-specific devices. This proof-of- concept study demonstrated the feasibility, antimicrobial properties, and computed tomography(CT) imaging characteristics of iodine/polyvinyl alcohol (PVA) 3D meshes and stents. Under scanning electron microscopy, cross-linked PVA displays smoother and more compacted filament arrangements. X-ray and transaxial CT images of iodized PVA vascular stents show excellent visibility and significantly higher Hounsfield units of radiopacity than control prints. Three-dimensional PVA prints stabilized by glutaraldehyde cross-linking and loaded with iodine through sublimation significantly suppressed Escherichia coli and Staphylococcus aureus growth in human blood agar disk diffusion assays. It is suggested that PVA 3D printing with iodine represents an important new synthetic platform for generating a wide variety of antimicrobial and high-visibility devices.

Surgical management of refractory nasal aspergillosis using iodine cadexomer dressings in three dogs

BACKGROUND

This case series describes surgical management of nasal aspergillosis refractory to conventional medical management or with evidence of cribriform plate osteolysis in three dogs.

METHODS

All dogs had surgical debridement of mucosa, nasal turbinates and necrotic debris via dorsal sinusotomy/rhinotomy. Sinuses were packed with iodine cadexomer-impregnated bandages for several weeks and affixed with tie-over bandages. Bandage changes were performed under sedation in 2/3 cases. Once mature granulation tissue covered all exposed bone, the tie-over bandages were removed and the sinusotomy/rhinotomy closed by apposing the skin edges.

CONCLUSION

This technique was well tolerated, effective and afforded a cure in all three patients. It should be considered in cases of cribriform lysis or lack of clinical response to conventional medical management.

Consensus on Wound Antisepsis: Update 2018

Wound antisepsis has undergone a renaissance due to the introduction of highly effective wound-compatible antimicrobial agents and the spread of multidrug-resistant organisms (MDROs). However, a strict indication must be set for the application of these agents. An infected or critically colonized wound must be treated antiseptically. In addition, systemic antibiotic therapy is required in case the infection spreads. If applied preventively, the Wounds-at-Risk Score allows an assessment of the risk for infection and thus appropriateness of the indication. The content of this updated consensus recommendation still largely consists of discussing properties of octenidine dihydrochloride (OCT), polihexanide, and iodophores. The evaluations of hypochlorite, taurolidine, and silver ions have been updated. For critically colonized and infected chronic wounds as well as for burns, polihexanide is classified as the active agent of choice. The combination 0.1% OCT/phenoxyethanol (PE) solution is suitable for acute, contaminated, and traumatic wounds, including MRSA-colonized wounds due to its deep action. For chronic wounds, preparations with 0.05% OCT are preferable. For bite, stab/puncture, and gunshot wounds, polyvinylpyrrolidone (PVP)-iodine is the first choice, while polihexanide and hypochlorite are superior to PVP-iodine for the treatment of contaminated acute and chronic wounds. For the decolonization of wounds colonized or infected with MDROs, the combination of OCT/PE is preferred. For peritoneal rinsing or rinsing of other cavities with a lack of drainage potential as well as the risk of central nervous system exposure, hypochlorite is the superior active agent. Silver-sulfadiazine is classified as dispensable, while dyes, organic mercury compounds, and hydrogen peroxide alone are classified as obsolete. As promising prospects, acetic acid, the combination of negative pressure wound therapy with the instillation of antiseptics (NPWTi), and cold atmospheric plasma are also subjects of this assessment.

A Comprehensive Review of Topical Odor-Controlling Treatment Options for Chronic Wounds

The process of wound healing is often accompanied by bacterial infection or critical colonization, resulting in protracted inflammation, delayed reepithelization, and production of pungent odors. The malodor produced by these wounds may lower health-related quality of life and produce psychological discomfort and social isolation. Current management focuses on reducing bacterial activity within the wound site and absorbing malodorous gases. For example, charcoal-based materials have been incorporated into dressing for direct adsorption of the responsible gases. In addition, multiple topical agents, including silver, iodine, honey, sugar, and essential oils, have been suggested for incorporation into dressings in an attempt to control the underlying bacterial infection. This review describes options for controlling malodor in chronic wounds, the benefits and drawbacks of each topical agent, and their mode of action. We also discuss the use of subjective odor evaluation techniques to assess the efficacy of odor-controlling therapies. The perspectives of employing novel biomaterials and technologies for wound odor management are also presented.

Application of Materials as Medical Devices with Localized Drug Delivery Capabilities for Enhanced Wound Repair

The plentiful assortment of natural and synthetic materials can be leveraged to accommodate diverse wound types, as well as different stages of the healing process. An ideal material is envisioned to promote tissue repair with minimal inconvenience for patients. Traditional materials employed in the clinical setting often invoke secondary complications, such as infection, pain, foreign body reaction, and chronic inflammation. This review surveys the repertoire of surgical sutures, wound dressings, surgical glues, orthopedic fixation devices and bone fillers with drug eluting capabilities. It highlights the various techniques developed to effectively incorporate drugs into the selected material or blend of materials for both soft and hard tissue repair. The mechanical and chemical attributes of the resultant materials are also discussed, along with their biological outcomes in vitro and/or in vivo. Perspectives and challenges regarding future research endeavors are also delineated for next-generation wound repair materials.

Radiopaque Hemocompatible Ruminant-Sourced Gut Material with Antimicrobial Physiognomies for Biomedical Applications in Diabetics

This study comprises the fabrication of a radiopaque gut material with its mechanical properties conforming to the US Pharmacopeia guidelines giving an antimicrobial advantage for suture application, especially in conditions such as diabetes mellitus, which has a high wound infection rate. Schiff base cross-linking iodination of the material is evinced by the spectroscopic studies, and antimicrobial properties owing to released iodine are evinced through in vitro studies. Modified gut sutures demonstrated favorable physicomechanical features such as appropriate tensile strength (440 ± 20 MPa) and knot strength (270 ± 20) alongside a mean radiopacity value of 139.0 ± 10 in comparison with that of the femoral shaft with 160 ± 10. The diabetic model showed absence of clinical signs of infection, supported by wound swab culture and the absence of necrosis in histology. Hemocompatibility studies evinced the absence of contact platelet activation and hemolysis alongside the customary coagulation response. These promising results highlight the stimulating potential of the process in the development of biomedical applications, necessitating persistent studies for its evidence-based applicability, particularly in diabetic patients.

Choosing a Wound Dressing Based on Common Wound Characteristics

Significance: Chronic wounds are a major healthcare burden.The practitioner should have an appropriate understanding of both the etiology of the wound as well as the optimal type of dressings to use. Fundamental wound characteristics may be used to guide the practitioner's choice of dressings. The identification of optimal dressings to use for a particular wound type is an important element in facilitating wound healing. Recent Advances: Researchers have sought to design wound dressings that aim to optimize each stage in the healing process. In addition, dressings have been designed to target and kill infection-causing bacteria, with the incorporation of antimicrobial agents. Critical Issues: Chronic wounds are frequently dynamic in presentation, and the numerous wound dressings available make dressing selection challenging for the practitioner. Choosing the correct dressing decreases time to healing, provides cost-effective care, and improves patient quality of life. Future Directions: Research into the mechanisms of wound healing has enhanced our ability to heal chronic wounds at a faster rate through the use of moisture-retentive dressings. Newer dressings are incorporating the use of nanotechnology by incorporating miniature electrical sensors into the dressing. These dressings are engineered to detect changes in a wound environment and alert the patient or practitioner by altering the color of the dressing or sending a message to a smartphone. Additional investigations are underway that incorporate biologic material such as stem cells into dressings.

New Twist on an Old Favorite: Gentian Violet and Methylene Blue Antibacterial Foams

Significance: Absorptive antibacterial dressings that assist in controlling bioburden without risks of cytotoxicity or residual absorption can be effectively used for prolonged periods throughout the wound healing continuum. Recent Advances: Until recently, gentian violet and methylene blue (GV/MB) antibacterial dressings have been commercially available only in polyvinyl alcohol (PVA) foam; polyurethane (PU) foam bonded with GV and MB with thin film backing is now commercially available. GV/MB PU foam does not require hydration or a necessary secondary dressing. GV/MB PVA and PU foam dressings were recently granted FDA clearance as antibacterial dressings, as opposed to bacteriostatic dressings as previously classified. Within the class of antibacterial dressings, GV/MB foam dressings are of lower cost alternative to silver- or iodine-based antibacterial dressings with no risk of absorption of any of the foam components into the tissues. Critical Issues: Control of wound bioburden levels by antibacterial agents and absorption of excess exudate are crucial in preventing infections that drastically increase the price of wound care. Use of GV/MB dressings may improve wound healing outcomes and decrease overall costs through super absorption, promotion of autolytic debridement, bioburden reduction, ease of use, and decreased dressing change frequency. Future Directions: Evolution in resistant bacterial strains will drive continual changes in advanced wound care products. Demand will increase for economically priced, versatile wound care dressings that assist in debridement, maintain a moist wound environment, absorb and trap bacterial debris, and decrease dressing change frequency.

Approach to chronic wound infections

Infection is the likeliest single cause of delayed healing in healing of chronic open wounds by secondary intention. If neglected it can progress from contamination to colonization and local infection through to systemic infection, sepsis and multiple organ dysfunction syndrome, and it can be life-threatening. Infection in chronic wounds is not as easy to define as in acute wounds, and is complicated by the presence of biofilms. There is, as yet, no diagnostic for biofilm presence, but it contributes to excessive inflammation - through excessive and prolonged stimulation of nitric oxide, inflammatory cytokines and free radicals - and activation of immune complexes and complement, leading to a delay in healing. Control of biofilm is a key part of chronic wound management. Maintenance debridement and use of topical antimicrobials (antiseptics) are more effective than antibiotics, which should be reserved for treating spreading local and systemic infection. The continuing rise of antimicrobial resistance to antibiotics should lead us to reserve their use for these indications, as no new effective antibiotics are in the research pipeline. Antiseptics are effective through many mechanisms of action, unlike antibiotics, which makes the development of resistance to them unlikely. There is little evidence to support the theoretical risk that antiseptics select resistant pathogens. However, the use of antiseptic dressings for preventing and managing biofilm and infection progression needs further research involving well-designed, randomized controlled trials.

The Topical Evolution: Free Ions, Orthomolecular Agents, Phytochemicals, and Insect-Produced Substances

Significance: A variety of topical antiseptic substances have been used historically to treat open wounds with suspected tissue infection or that are slow to heal. However, the effectiveness of these substances in treating infected or recalcitrant wounds remains controversial. Recent Advances: Newly formulated topical antiseptics delivered through differing dressing technologies, such as ionic substances, hold the potential to limit the development of and treat antibiotic-resistant microbes in open wounds. Other topically delivered substances, such as insect-derived substances, orthomolecular agents, and phytochemicals, also present opportunities to optimize wound healing by decreasing tissue bioburden and facilitating the wound healing process. Critical Issues: Limited systemic perfusion of open wounds in individuals with certain diagnoses, such as peripheral arterial disease or necrotizing infection and the increasing number of antibiotic-resistant wound pathogens, suggests a continued role for topically applied antiseptic agents. Likewise, the failure of wounds to heal when treated with standard of care therapy opens the door to innovative treatment approaches that include the natural substances described in this article. Future Directions: Evidence for the use of select topical antiseptic agents from each of the aforementioned categories will be discussed in this article. Additional well-controlled clinical studies are needed to provide definitive recommendations for many of these topical agents.

Topical and biologic therapies for diabetic foot ulcers

Chronic DFUs are a growing global health concern due to the implied high rates of morbidity and mortality. Standard-of-care modalities sometimes are not sufficient for some recalcitrant ulcers. The use of adjuvant topical therapies including advanced dressings and biologic therapies should be considered in patients whose DFU did not reduce in size after receiving standard care for a period of 4 weeks. These advanced treatments must be used in combination with standard care measures, including debridement, moist wound healing, offloading, and infection control.

Innovative approaches in wound healing: trajectory and advances

Wound is one of the oldest suffering associated with the mankind and its history is as old as humanity. Advances in the field of medical sciences created a pile of knowledge and paved the path for the development of a separate branch specifically devoted for wound healing. The understanding and treatment strategies for wound healing have gone through a great revolution. This article reviews all the aspects of wound healing including the pathway, types and recent advances made in the wound care management in particular moist wound dressings using natural polymers, skin grafts, debridement, growth factor and drug delivery.

Wound healing under the effect of iodine cadexomer in rats

PURPOSE: To assess vthe action of iodine cadexomer in the healing process of surgical wounds in rats and if cytotoxicity occurs with the systemic absorption of iodine. METHODS: Thirty six Wistar rats were used and performed 53 wounds with surgical punch of 6 mm diameter on them. Two lesions were made diametrically opposed on groups with distilled water (GAD) and sodium chloride (GCS); on the right lesions were used bandage with distilled water and on the left ones dressing with sodium chloride. In cadexomer iodine (GCI) group, a punch injury was made only on the left side and the dressing was carried out with cadexomer iodine. The groups were divided in two sub-groups according to the day of death (7 and 14). Microscopically was used H&E staining, through which the inflammation could be observed and also the neovascularization. Staining with Masson trichrome studied fibrosis. TSH and free T4 were used for absorption recognition of iodine, and its toxic potential was performed before death with the animal anesthetized. RESULTS: Microscopic analysis showed more marked intensity of inflammation in group GAD, subgroup 14 days. Neovascularization showed be discrete in GCS sub-group 14 days. Fibrosis was more pronounced in the group GCI. Comparing the types of treatment, there was statistical significance between groups GCI and GCS (p<0.013). The TSH and T4, showed no difference between the control group and GCI in relation to the absorption of iodine. In evaluating the GCI and control groups, within each treatment, statistical significance was found between them (p<0.001) when compared the days of observation. CONCLUSION: Cadexomer iodine had beneficial effects in all phases of the healing process without cytotoxicity due iodine absorption.

Influence of various treatments including povidone-iodine and healing stimulatory reagents in a rabbit ear wound model

Selecting an appropriate treatment for a given case of skin wound is crucial for inducing optimal healing. We used an animal model developed from normal rabbit ears in order to assess the efficacy of treatments for skin wounds with or without a wet dressing, anti microbial reagent or topical wound-stimulatory reagents. The degree of healing in each group was evaluated and compared using four histological parameters: (i) degree of reepithelialisation, (ii) amount of granulation tissue formation, and (iii) the number of capillary lumens and (iv) fibroblasts in the granulation tissue. Treatment using wet dressings resulted in an increase in capillary number compared with the open dry wound. Although the retention of povidone-iodine (PI) in wound tissue after application significantly inhibited reepithelialisation (P < 0.05), rinsing PI off with saline was comparable in effect to using only a wet dressing. The three topical reagents, namely, basic fibroblast growth factor, prostaglandin E1 and dibutyryl cyclic adenosine monophosphate, significantly improved reepithelialisation (P < 0.05). In conclusion, wounds should be kept hydrated by applying topical reagents. If there are any signs of bacterial infection, PI can be applied and rinsed later with saline in order to minimise its cytotoxic effects.

The science of wound bed preparation

The concept of wound bed preparation (WBP) heralded a new era in terms of how we treat wounds. It emphasized the difference between acute and chronic wounds, and it cemented the idea that the processes involved in the healing of acute wounds do not apply completely to the healing of chronic wounds. The arbitrary division of the normal healing process into the phases of hemostasis, inflammation, proliferation, and maturation addresses the events in acute wound healing. We have realized that the impediments to healing in chronic wounds lead to a failure to progress through these phases and are independent factors that make the chronic wound a much more complex condition. A major advance in resolving or addressing the chronic wound has been the concept of WBP. WBP allows us to address the problems of wound healing individually the presence of necrotic tissue, hypoxia, high bacterial burden, corrupt matrix, and senescent cells within the wound bed. In WBP we can optimize our therapeutic agents to accelerate endogenous healing or to increase the effectiveness of advanced therapies.

Critical evaluation of cadexomer-iodine ointment and povidone-iodine sugar ointment

Topical iodine forms are used for infected and necrotic pressure ulcers. Despite antimicrobial advantages several potential disadvantages were observed with controversial results. To clarify the controversy, the reactivity of povidone-iodine (PI) sugar ointment and cadexomer-iodine (CI) ointment toward biological components was investigated. L-Tyrosine as a component of proteins and egg lecithin as a component of lipid membranes were reacted with forms of iodine. Furthermore, water absorption abilities of ointments were investigated. The reactions of PI sugar ointment and CI ointment with L-tyrosine were reversely dependent on iodine concentrations. CI ointment reacted with lecithin in an iodine concentration dependent manner, while PI sugar ointment reacted with lecithin in an iodine concentration independent steady manner. However, at the clinically relevant iodine concentration (0.1, w/v%) PI sugar ointment reacted efficiently with L-tyrosine and less efficiently with lecithin, while CI ointment reacted efficiently with lecithin and less efficiently with L-tyrosine. Water absorption rate constant was 29.9 mg/cm(2)/min(0.5) for PI sugar ointment and 15.3 for CI ointment. Water absorption capacity per weight over 24 h was 26% forPI sugar ointment and 76% for CI ointment [corrected]. These results suggest that PI sugar ointment and CI ointment have different characteristics for iodine reactivity and water absorption.

Topical antimicrobial therapy of chronic wounds healing by secondary intention using iodine products

All open wounds healing by secondary intention are contaminated by bacteria and in chronic wounds this can progress through colonisation to invasive infection. Iodine products reduce bacterial load and are active against most species of micro-organisms, and certainly those encountered in chronic wound care. This review evaluates the use of iodine products in chronic wound care including povidone-iodine solutions and cadexomer iodine. Antiseptics containing iodine are relatively cheap, resistance is unknown and concerns about systemic toxicity are probably overstated. More widespread use of these agents as topical anti-microbials in chronic wound care should be considered to reduce the need for systemic antibiotics when colonisation has progressed to invasive infection with systemic signs.

Treating the chronic wound: A practical approach to the care of nonhealing wounds and wound care dressings

Chronic wounds are a major healthcare problem costing the United States billions of dollars a year. The American Academy of Dermatology has underscored the significance of wound care in dermatological practice. It is critical for all dermatologists to understand the elements of diagnosis and therapy. We emphasize major aspects of diagnosis and present a simple classification of wound dressings with guidelines for usage and relative cost data.

LEARNING OBJECTIVE

After completing this learning activity, participants should be able to diagnose common types of chronic wounds, formulate a therapeutic plan, and describe the major classes of topical therapies and dressings for the chronic wound.

Iodine revisited

Iodine is an antiseptic that has been used in wound care for more than 150 years. Traditional formulations of iodine had serious limitations that were reduced in later products. Much has been written about iodine and opinions on its clinical efficacy are divided. There have been reviews of the chemical properties of iodine, its antimicrobial activity, human physiology, cytotoxicity and its clinical effectiveness, but few have addressed all these aspects. With the recent development of iodine-containing wound care products and the continued publication of laboratory and clinical studies, it seems timely to reassess the evidence relating to the effectiveness of iodine for treating wounds. This literature review attempts to provide an appropriate chemical and physiological background of the characteristics of iodine in order to provide a sound basis for understanding the available microbiological and clinical data. It will show that understanding the factors that contribute to the activity and potential cytotoxicity of iodine are important in evaluating the clinical evidence. Although definitive studies are needed, the sustained delivery of low doses of free iodine offers the potential to inhibit a broad range of microbial species without selecting for resistant strains or inducing cytotoxic effects.

The science of wound bed preparation

The concept of wound bed preparation (WBP) heralded a new era in terms of how we treat wounds. It emphasized the difference between acute and chronic wounds, and it cemented the idea that the processes involved in the healing of acute wounds do not apply completely to the healing of chronic wounds. The arbitrary division of the normal healing process into the phases of hemostasis, inflammation, proliferation, and maturation addresses the events in acute wound healing. We have realized that the impediments to healing in chronic wounds lead to a failure to progress through these phases and are independent factors that make the chronic wound a much more complex condition. A major advance in resolving or addressing the chronic wound has been the concept of WBP. WBP allows us to address the problems of wound healing individually-the presence of necrotic tissue, hypoxia, high bacterial burden, corrupt matrix, and senescent cells within the wound bed. In WBP we can optimize our therapeutic agents to accelerate endogenous healing or to increase the effectiveness of advanced therapies.

Mixture of sugar and povidone-iodine stimulates healing of MRSA-infected skin ulcers on db/db mice

The topical application of a mixture of sugar and povidone-iodine (PI) has been reported to accelerate the healing of cutaneous wounds and ulcers by promoting reepithelialization and granulation tissue formation, as well as by having an anti-microbial effect. In order to clarify the efficacy of a 70% sugar and 3% PI paste (U-PASTA(SP) on infectious skin ulcers, we made a bacterial infection model using methicillin-resistant Staphylococcus aureus (MRSA) on the skin of diabetic db/db mice, and investigated the effect of the paste on the healing process of wounds. Full-thickness wounds were made on the backs of female diabetic mice, (C57BL/ksJ db/db) and inoculated with S. aureus. SP was applied to the closed wounds for 8 days. The degree of repair was evaluated using three histological parameters: The degree of reepithelialization was given a percentage value of 0-100%; the amount of granulation tissue was quantified by measuring the area of granulation (mm(2)); and the number of capillary lumens in the granulation tissue was counted in the complete wound cross-section at 100x magnification. In addition, the colony-forming units (CFU) of MRSA on the wounds were counted. Continuous MRSA infection in the wounds of db/db mice was demonstrated with macroscopic and histopathological images. Wounding and infection caused by MRSA on the back of the diabetic mice significantly induced delayed reepithelialization, granulation tissue formation with inflammatory cell infiltrate and increased CFU on wounds (P < 0.01, respectively) compared to those of the MRSA-infected normal mice. Application of SP significantly accelerated reepithelialization (P < 0.01) and decreased CFU (P < 0.05) of the ulcers in the MRSA-infected wounds, compared to the non-treated group. Histopathological evaluation and CFU on this animal model revealed no significant difference between Methicilin-sensitive Staphylococcus aureus and MRSA infection. These results indicate that wounding on db/db mice provides a useful animal model of bacterial skin infections, and that SP is an effective topical agent for the treatment of diabetic skin ulcers.

Triphala promotes healing of infected full-thickness dermal wound

BACKGROUND

Infection is a major problem in the management of wounds. Even though the development of synthetic antimicrobial agents persists, drug resistance and toxicity hinder their way. Many plants with multi-potent pharmaceutical activities may offer better treatment options, and Triphala (dried fruits of Terminalia chebula, Terminalia bellirica, and Phyllanthus emblica) are potential formulations evaluated for healing activity on infected wound as it possesses numerous activities.

MATERIALS AND METHODS

Alcoholic extract of Triphala has shown in vitro antimicrobial activity against wound pathogens such as Staphylococcus aureus, Pseudomonas aeruginosa, and Streptococcus pyogenes. An ointment was prepared from the Triphala extract (10% w/w) and assessed for in vivo wound healing on infected rat model by rate of healing, bacterial count, biochemical analysis, and expression of matrix metalloproteinases.

RESULTS

The treated group has shown significantly improved wound closure. Assessment of granulation tissue on every fourth day showed significant reduction in bacterial count with significant level of collagen, hexosamine, uronic acid, and superoxide dismutase in the treated group (P < 0.01). Reduction of matrix metalloproteinase expression observed in the treated group by gelatin zymography and immunoblotting confirms our in vivo assessment.

CONCLUSIONS

The above results showed the antibacterial, wound healing, and antioxidant activities of Triphala ointment, necessary for the management of infected wounds. Active principles of the Triphala may be further evaluated and used as an excellent therapeutic formulation for infected wounds.

Cadexomer as well as cadexomer iodine induces the production of proinflammatory cytokines and vascular endothelial growth factor by human macrophages

Although cadexomer iodine is widely used for the treatment of skin ulcers such as decubitus ulcers, the mechanism by which it enhances wound healing is not clear. Recently, it has been demonstrated that macrophages play an important role in wound healing by inducing inflammation and angiogenesis. We examined the effects of cadexomer and cadexomer iodine on tumor necrosis factor (TNF)-alpha, interleukin (IL)-1 beta, IL-6, IL-8, IL-10, IL-12 p 40, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) production by macrophages. Human macrophages were obtained by culturing CD14+ monocytes with macrophage colony stimulating factor (M-CSF) in the presence or absence of cadexomer or cadexomer iodine. The production of cytokines and the expression of mRNA were evaluated by enzyme linked immunosorbent assay (ELISA) of the culture supernatants and by reverse transcriptase polymerase chain reaction (RT-PCR) analysis, respectively. In addition, we examined the tissue concentration of VEGF in the wounds treated with or without cadexomer iodine. Cadexomer and cadexomer iodine significantly increased the expression of IL-1 beta, IL-8, TNF-alpha and VEGF mRNA, while they did not affect that of IL-6, IL-10, IL-12 p 40 or bFGF mRNA. In addition, they significantly increased the production of IL-1 beta and TNF-alpha. Although we could not detect increased production of VEGF in the culture supernatants, the western blot analysis of macrophages demonstrated the increased production of VEGF by the treatment with either cadexomer or cadexomer iodine. The treatment with cadexomer iodine increased the tissue concentration of VEGF in the skin wounds. These data suggest that cadexomer and cadexomer iodine have beneficial effects on wound healing in addition to those related to their antibacterial activity.

Microengineered surface topography facilitates cell grafting from a prototype hydrogel wound dressing with antibacterial capability

Skin wounds derive therapeutic benefit from redeployment of dermal tissues, whether as split-thickness allo- and autografts or as biological dressings comprising cultured cells. However, the clinical outcome is strongly influenced by the techniques used for cell/tissue grafting and also the microbiological status of the wound. Here we report that microtopography incorporated into the surface of a novel polymeric material, derivatized with fibronectin to promote attachment and encourage motility, improved the efficiency of cell transfer onto de-epithelialized human skin ex vivo. The microtopography had two functions, first as a conduit for migrating cells to cross between the vehicle and recipient surface and second to shield adherent cells from destruction by mechanical shearing during handling and application. Quantitative analysis showed that topographic projections (columns) rather than recesses (pits) in the hydrogel surface achieved the highest efficiency of cell transfer. In order to address the crucial relevance of microbiological contamination to the success of wound grafting, the effect of iodine on several common bacterial pathogens was examined using an XTT+C(Q10) kinetic cell viability assay. Increasing concentrations of iodine initially stressed and after 0.5% v/v were subsequently bacteriocidal for Gram-negative Pseudomonas aeruginosa and Escherichia coli and Gram-positive Bacillus subtillis and Staphylococcus aureus. Slightly higher doses of iodine (approx 1-1.5% v/v) were required to kill HaCaT cells outright, but for both pro- and eukaryotes the major determinant of cytotoxicity was absolute dose rather than duration of exposure. Iodine delivered by the hydrogel at low concentration was bacteriostatic but not apparently cytotoxic to epithelial cells as measured by MTT end-point cell viability assay. Zone of inhibition studies confirmed that bacteriocidal quantities of neomycin, phenol red, and silver could also be delivered using the same hydrogel. This research suggests that grafting cell-based biological dressings to wounds using a topographically modified hydrogel dressing capable of simultaneous reducing the microbiological threat to a successful outcome may be a realistic clinical proposition.

Clinical aspects of full-thickness wound healing

Optimal management of full-thickness wounds requires a thorough knowledge of wound-healing principles and practices. In the absence of underlying disease, almost every full-thickness wound will heal with minimal intervention; however, the process can be enhanced by judicious wound management. The first clinical decision to be made is whether to repair the wound or to allow it to heal by second intention. This decision is guided by a host of objective and subjective factors. Reconstruction options include primary closure, flaps, and grafts. Materials to aid reconstruction, including the introduction of tissue adhesives, continue to evolve. Both primary and secondary intention wounds are aided by occlusive dressings and adjutants. A plethora of wound-healing adjuncts have been developed to aid wound healing in diseased states, and a working knowledge of their use is beneficial in managing all full-thickness wounds.