Treatment Of Infected Wounds Research Articles

Synergistic Efficacy, Antimicrobial and Wound Healing Potentials of Milled Persea Americana Seed / Syzygium Aromaticum Oil Against Albino Rats and Wound Isolates

This study aimed to investigate the effects of oil avocado extracts, vegetable oil, Goya oil, and clove oil and its healing potential on male and female albino rats and their antibacterial activity against surgical wound isolates. The antimicrobial efficacy of avocado seed oil and cloves extract against surgical wound isolates was investigated using the agar well diffusion method and a microplate reader to detect the killing time rate of each isolate against oil extracts applied topically to the wounds of albino rats. The following bacteria were isolated, Escherichia coli, Pseudomonas aeruginosa, Klebsiella oxytoca, Chrysobacterium meningosepticum, Klebsiella oxytoca, Escherichia coli, Acinetobacter baumannii and Bergeyella zoochelum. The wound healing process was evaluated by measuring the serum and tissue bioassays and tissue repair enzymes. It was observed that Avocado seed oil infused in vegetables has the highest micro-titre reading against Bergeyella zoochelum (0.199) and Avocado oil infused in vegetable oil with cloves (0.100) against Chrysobacterium meningo septicum at 24 and 48 hours, respectively, this denotes bacteriostatics and Avocado oil infused in Goya with cloves against Bergeyella zoochelum (0.046) has the lowest value and Avocado oil infused in n-hexane against Escherichia coli has the highest value (0.080); this denotes bacteriocide activity of extracted oil. It was observed that the surgical wound on the albino rats closed within seven days and the measured tissue and serum bioassay were relatively under standard. The results of this study suggest that avocado seed oil and clove oil have potential natural alternatives to synthetic antimicrobial agents and treatment of wounds and wound infection in albino rats, as the avocado seed oil and clove used in this study inhibited all the surgical wound isolates.

Antimicrobial, Anti‐inflammatory, and Wound Healing Properties of Myrtus communis Leaf Methanolic Extract Ointment on Burn Wound Infection Induced by Methicillin‐Resistant Staphylococcus aureus in Rats

Objective(s). Given the increasing rate of methicillin‐resistant Staphylococcus aureus (MRSA) resistance to antibiotics, the use of plant‐based antimicrobials to treat the infection has been considered. This study is aimed at evaluating the effect of Myrtus communis leaf extract ointment and silver nanoparticles on the healing of burn wounds caused by MRSA in rats. Materials and Methods. In a research experiment, 48 male Wistar rats were anesthetized and second‐degree burns were induced on their backs. The rats’ wounds were then uniformly inoculated with MRSA. Various treatments were applied to the burn wounds daily, including Myrtus ointment, silver nanoparticles, silver nanoparticles‐Myrtus ointment, silver sulfadiazine‐Myrtus ointment, silver sulfadiazine 1%, mupirocin ointment, and a positive control. The study measured the antimicrobial effects, wound area, percentage of wound healing, antioxidant capacities, malondialdehyde, and nitric oxide concentrations in the serum of the rats. Data analysis was performed using GraphPad software, with one‐way ANOVA and Tukey’s tests used to determine the statistical significance of the results. Results. Rats treated with Myrtus ointment, silver nanoparticles‐Myrtus ointment, and mupirocin had reduced bacterial growth compared to the positive control group, nanoparticle ointment, and silver sulfadiazine (P < 0.05). The wound area of the Myrtus ointment group decreased significantly on the seventh and fourteenth days, as well as the level of MDA and nitric oxide, compared to the other groups. In Myrtus and silver sulfadiazine‐Myrtus ointment increased the thickness of the epidermis and dermis compared to the other groups. Conclusion. Based on the anti‐inflammatory, antimicrobial, and wound healing properties of Myrtus, with further studies, an ointment of this plant may be used as a main or complementary treatment for burn wound infections caused by MRSA.

Advances of antimicrobial dressings loaded with antimicrobial agents in infected wounds.

Wound healing is a complex process that is critical for maintaining the barrier function of the skin. However, when a large quantity of microorganisms invade damaged skin for an extended period, they can cause local and systemic inflammatory responses. If left untreated, this condition may lead to chronic infected wounds. Infected wounds significantly escalate wound management costs worldwide and impose a substantial burden on patients and healthcare systems. Recent clinical trial results suggest that the utilization of effective antimicrobial wound dressing could represent the simplest and most cost-effective strategy for treating infected wounds, but there has hitherto been no comprehensive evaluation reported on the efficacy of antimicrobial wound dressings in promoting wound healing. Therefore, this review aims to systematically summarize the various types of antimicrobial wound dressings and the current research on antimicrobial agents, thereby providing new insights for the innovative treatment of infected wounds.

CaO2-Cu2O micromotors accelerate infected wound healing through antibacterial functions, hemostasis, improved cell migration, and inflammatory regulation.

During the wound tissue healing process, the relatively weak driving forces of tissue barriers and concentration gradients lead to a slow and inefficient penetration of bioactive substances into the wound area, consequently showing an impact on the effectiveness of deep wound healing. To overcome these challenges, we constructed biocompatible CaO2-Cu2O "micromotors". These micromotors reacted with the fluids at the wound site, releasing oxygen bubbles and propelling particles deep into the wound tissue. In vitro experimental results revealed that these micromotors not only exhibited antibacterial and hemostatic functions but also facilitated the migration of dermal fibroblasts and vascular endothelial cells, while modulating the inflammatory microenvironment. A methicillin-resistant Staphylococcus aureus infected full-thickness-wound model was created in rats, in which CaO2-Cu2O micromotors markedly expedited the wound healing process. Specifically, CaO2-Cu2O provided a sterile microenvironment for wounds and increased the amounts of M1-type macrophages during infection and inflammation. During the proliferation and remodeling stages, the amount of M1 macrophages gradually decreased, while the amount of M2 macrophages increased, and CaO2-Cu2O did not prolong the inflammatory period. Furthermore, the introduction of a regenerated silk fibroin (RSF) film on the wound surface successfully enhanced the therapeutic effects of CaO2-Cu2O against the infected wound. The combined application of oxygen-producing CaO2-Cu2O micromotors and a RSF film demonstrates significant therapeutic potential and emerges as a promising candidate for the treatment of infected wounds.

Atomically dispersed nanozyme-based synergistic mild photothermal/nanocatalytic therapy for eradicating multidrug-resistant bacteria and accelerating infected wound healing.

Constructing a synergistic multiple-modal antibacterial platform for multi-drug-resistant (MDR) bacterial eradication and effective treatment of infected wounds remains an important and challenging goal. Herein, we developed a multifunctional Cu/Mn dual single-atom nanozyme (Cu/Mn-DSAzymes)-based synergistic mild photothermal/nanocatalytic-therapy for a MDR bacterium-infected wound. Cu/Mn-DSAzymes with collaborative effects exhibit remarkable dual CAT-like and OXD-like enzyme activities and could efficiently catalyze cascade enzymatic reactions with a low level of H2O2 as an initial reactant to produce reparative O2 and lethal ˙O2-. Moreover, a black N-doped carbon nanosheet supports of Cu/Mn-DSAzymes show superior NIR-II-triggered photothermal performance, endowing them with photothermal-enhanced dual enzyme catalysis. In addition, such enhanced dual enzyme catalysis likely improves the susceptibility and lethality of photothermal effects on MDR bacteria. In vitro and in vivo studies demonstrate that Cu/Mn-DSAzyme-mediated synergistic nanocatalytic and photothermal effects possess dramatic antibacterial outcomes against MDR bacteria and evidently reduced inflammation at wound sites. Moreover, the combined photothermal effect and O2 release mediated by Cu/Mn-DSAzymes promotes macrophage polarization to reparative M2 phenotype, collagen deposition, and angiogenesis, considerably accelerating wound healing. Therefore, Cu/Mn-DSAzyme-based synergetic dual-modal antibacterial therapy is a promising strategy for MDR bacterium-infected wound treatment, owing to their excellent antibacterial ability and significant tissue remodeling effects.

Application of Aleppo pine extract for skin burn treatment.

To investigate the Pinus halepensis extracts and determine its healing and antibacterial effects, and to evaluate the treatment of skin burns. Aqueous and ethanolic extracts and topical based on Aleppo pine plant extracts were prepared. Thirty male and female Wistar rats were used to study the cutaneous toxicity of extracts from the bark of P. halepensis. The extracts' healing potential for burn wounds were also assessed by evaluating the clinical and macroscopic aspects of the wounds. The antibacterial activity of crude extracts of P. halepensis as well as its wound healing abilities was verified in this investigation. In animals with acute dermal toxicity, there were no signs of treatment-related toxicity or death. The extracts of these plants could be transformed into phytomedicines for the treatment of infected wounds. The results demonstrated that formulated ointments are successful in treating second-degree burns in rats and may be suitable for the short-term therapeutic treatment of second-degree burns. This study successfully answered our problem, regarding the efficacy of our extract for treating second-degree burns in rats. Further studies are needed to confirm these results by identifying the molecules responsible for these activities and examining their mechanism of action.

Evaluation of the antibacterial properties of commonly used clays from deposits in central and southern Asia

Abstract One potential solution to the rising threat of antibacterial drug resistance is the application of therapeutic clays to treat wound infections. Clays with antibacterial activity have been identified from a range of sources with their antibacterial properties often attributed to the release of toxic metal ions such as Fe(II) and Al(III). Here, clays from Afghanistan, Azerbaijan and Bangladesh that are utilized for washing and healing purposes were examined. Their antibacterial activities were assessed in suspension and as aqueous leachates against representative Gram-negative, Escherichia coli, and Gram-positive, Bacillus subtilis, bacteria. The majority of the clays conferred no deleterious effect and, in fact, tended to promote bacterial growth, likely as a result of released organic and inorganic nutrients. However, one of the clays, obtained from the Dhaka region of Bangladesh, displayed significant bactericidal activity against E. coli and B. subtilis as a clay suspension but not as an aqueous leachate. Further experiments confirmed that contact between clay and the bacteria was necessary for most of the antibacterial effects. Detailed analysis of bulk and <2 μm clay fraction mineralogy and geochemistry revealed no single defining parameter or mineral component that could be used to easily distinguish natural clays with antibacterial properties from those without. Overall, the results suggest a mechanism of antibacterial action of the Dhaka clay that arises from acidic conditions, likely enabled by the absence of calcite in the bulk clay, metal release, the presence of interstratified chlorite-smectite, and direct clay–bacteria interactions.

Discovery of novel antibacterial agent for the infected wound treatment: all-hydrocarbon stapling optimization of LL-37.

Rationale: Antimicrobial peptide LL-37 has been recognized as a favorable alternative to antibiotics due to its broad antibacterial spectrum, low resistance development and diverse biological activities. However, its high manufactory cost, poor proteolytic stability, and unpredictable cytotoxicity seriously hindered its medical translation. Methods: To push the frontiers of its clinical application, all-hydrocarbon stapling strategy was exploited here for the structural modification of KR-12, the core and minimal fragment of LL-37. Results: Based on a library of KR-12 derivatives that designed and synthesized to be stapled at positions of either i, i+4 or i, i+7, structure to activity relationship was investigated. Among them, KR-12(Q5, D9) with the glutamine and aspartic acid residues stapled displayed increased helical content and positive charge. The reinforced α-helical conformation not only protected it from proteolytic hydrolysis but also improved its antibacterial efficacy via effective membrane perturbation and anti-inflammatory efficacy via compact LPS binding. Besides, the increased positive charge endowed it with an enhanced therapeutic index. On infected wound mouse model, it was demonstrated to eliminate bacteria and promote wound closure and regeneration effectively. Conclusion: Overall, the all-hydrocarbon stapling was proven to lay the foundation for the future development of antibacterial agents. KR-12(Q5, D9) could serve as a lead compound for the clinical treatment of bacterial infections.

Uji Aktivitas Antibakteri Ekstrak Metanol Propolis dari Lebah Kelulut (Heterotrigona itama) terhadap Bakteri Pseudomonas aeruginosa dan Staphylococcus aureus

One of the causes of infection is influenced by the occurrence of wounds. Treatment of infected wounds using antibiotics. But antibiotics causes resistance. Then another alternative material from natural ingredients is used, is Propolis from Heterotrigona itama bees. This study aims to determine the inhibition, MIC and MBC of Propolis methanol extract with concentrations of 10%,20%30%,40%,50% against Pseudomonas aeruginosa and Staphylococcus aureus. Research uses experimental research with a non-probability sampling technique, purposive sampling. The extraction method uses methanol solvent maceration. Antibacterial test was carried out by disc diffusion method, positive control of 0.1% clindamycin, negative control of DMSO. The independent variable is the concentration of propolis methanol extract and the dependent variable is the inhibition zone formed and the MIC and MBC values. Analyzed statistically using the ANOVA. Propolis methanol extract inhibited Pseudomonas aeruginosa bacteria at concentrations of 10%:7.74mm, 20%:8.05mm, 30%:10.00mm, 40%:10.05mm, 50%:12,25mm, and can inhibit the growth of Staphylococcus aureus bacteria at concentrations of 10%:7,05mm, 20%:8.00mm, 30%:10.20mm, 40%:11.15mm, 50%:12,05mm. MIC and MBC methanol extract of propolis on the bacteria Pseudomonas aeruginosa and Staphylococcus aureus of 100 mg/ml. Statistical test results showed that all concentrations of propolis methanol extract had a significant difference with the positive control of Clindamycin 0.1%.

Harnessing antimicrobial peptide-coupled photosensitizer to combat drug-resistant biofilm infections through enhanced photodynamic therapy

Bacterial biofilm-associated infection was one of the most serious threats to human health. However, effective drugs for drug-resistance bacteria or biofilms remain rarely reported. Here, we propose an innovative strategy to develop a multifunctional antimicrobial agent with broad-spectrum antibacterial activity by coupling photosensitizers (PSs) with antimicrobial peptides (AMPs). This strategy capitalizes on the ability of PSs to generate reactive oxygen species (ROS) and the membrane-targeting property of AMPs (KRWWKWIRW, a peptide screened by an artificial neural network), synergistically enhancing the antimicrobial activity. In addition, unlike conventional aggregation-caused quenching (ACQ) photosensitizers, aggregation-induced emission (AIE) PSs show stronger fluorescence emission in the aggregated state to help visualize the antibacterial mechanism. In vitro antibacterial experiments demonstrated the excellent killing effects of the developed agent against both Gram-positive (G+) and Gram-negative (G–) bacteria. The bacterial-aggregations induced ability enhanced the photoactivatable antibacterial activity against G– bacteria. Notably, it exhibited a significant effect on destroying MRSA biofilms. Moreover, it also showed remarkable efficacy in treating wound infections in mice in vivo. This multifunctional antimicrobial agent holds significant potential in addressing the challenges posed by bacterial biofilm-associated infections and drug-resistant bacteria.

VAC Therapy as Part of Complex Treatment of Deep Sternal Wound Infection in Cardiosurgical Patients: First Experience

The aim. To improve the immediate and long-term results of treatment of cardiac surgery patients, by determining the feasibility of using wound therapy with negative pressure (vacuum assisted closure [VAC] therapy) as part of the complex tactics of postoperative management of patients with deep sternal wound infection (DSWI).
 Materials and methods. A single-center, retrospective, observational study of the clinical data of 12 patients who underwent open-heart surgery using median sternotomy and who developed a DSWI was conducted. The mean age of the patients was 66.2 ± 2.2 years. The patients were divided into 2 groups, depending on the type of the treatment they received: group 1 included 5 (41.67%) subjects with the installation of a flow-washing system; group 2 included 7 (58.33%) subjects receiving negative pressure wound therapy.
 Results. The use of VAC therapy contributed to the reduction of all indicators characterizing the course of the wound process, compared to patients treated with traditional methods. The duration of hospitalization was 36.2 ± 3.3 days in group 1 and 42 ± 4.0 days in group 2. The level of in-hospital mortality in the studied group receiving negative pressure wound therapy was 14.29% (1 patient) versus 80% (4 patients) in the group with flow-irrigation drainage.
 Conclusions. Deep sternal wound infection is a very serious postoperative complication in cardiac surgical patients with a high in-hospital mortality rate. Diabetes mellitus, obesity, immunopathies are the main risk factors. VAC therapy in patients with DSWI allows to adequately repair the wound in a shorter time while maintaining the patient’s mobility, as well as to significantly reduce the duration of wound drainage and, as a result, the length of hospitalization.

Клініко-імунологічний підхід до лікування інфекції акушерської хірургічної рани в породілей

Purpose - study of the effectiveness of treatment of obstetric surgical wound infection in parturient women with the use of drugs with sorption-detoxification and immunomodulatory properties, which will make it possible to develop and implement a pathogenetically justified method of therapy for this pathology in the postpartum period and obtain a positive economic effect. Materials and methods. To fulfill the purpose of the study, 115 parturient women with purulent wounds of the anterior abdominal wall (after caesarean section) and perineum (episio-, perineotomy) were examined, who, depending on the treatment method, were divided into groups. The Group I - 42 women in labor with purulent wounds, who were treated with organosilicon sorbent gentaxan (application sorption); the Group II - 45 women in labor with purulent wounds, who were treated with organosilicon sorbent Gentaxan (application sorption) and immunomodulator Laferon (intramuscular); the Group III (control) - 28 women in labor with purulent wounds, who were treated with traditional methods. The clinical picture of the healing process was monitored by local symptoms in the wound - hyperemia, edema, tissue infiltration, the number and nature of the compartment. The immune status of women in labour before and after treatment was studied. The material for the study of general immunity was peripheral blood, which was taken from the moment of infection of the obstetric surgical wound. To assess the state of general immunity, the total number of T-lymphocytes (CD3+), their immunoregulatory subpopulations - T-helpers/inducers (CD4+) and T-suppressors/killers (CD8+), the number of B-lymphocytes (CD22+), NK cells (CD16+), the immunoregulatory index (CD4+/CD8+) was calculated. Statistical data processing was carried out using the package of application programs Microsoft Excel 5.0 and using the standard version Statistica 8.0. The difference in indicators was considered statistically significant at Р<0.05. Results and conclusions. The use of drugs with immunomodulatory and sorption properties in the treatment of purulent wounds shows an advantage over traditional methods of therapy, which has increased the effectiveness of treatment of obstetric surgical wound infection in women in labour. In turn, the complex method of treatment with the use of gentaxane and laferon has an advantage over gentaxane monotherapy due to a significant restoration of the indicators of the cellular immune system, which affects faster cleansing of the wound from dead and non-viable tissues, rapid elimination of edema and inflammation in the wound and acceleration of reparative processes. This makes it possible to recommend the above method for widespread clinical use in obstetric practice. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of the participating institution. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.

Juniperus oxycedrus L. ssp. Essential Oil Microneedles: A Promising Antimicrobial and Wound Healing Activity.

The use of essential oil (EO) in treating infected wounds is still challenging. A lot of effort has been made to make such an application more convenient. Recently, microneedles (MNDs) have been considered as a smart dermal delivery system to overcome the poor absorption and distribution, low bioavailability, and skin penetration of some drugs. The aim of our study is to evaluate the wound healing activity of juniper-EO-loaded MNDs (EO MNDs) against wounds with bacterial and fungal infection. The Polyvinylpyrrolidone (PVP) MNDs were prepared using the gel-filled mold technique and loaded with juniper EO. In vivo models were created and wounds on rats were infected with two clinically isolated bacterial strains Pseudomonas aeruginosa and Staphylococcus aureus. Furthermore, Candida albicans was used to mimic fungal infection and juniper EO MNDs were tested. The obtained results showed an improvement in wound healing which started from the third day after application of the juniper EO MNDs, and at the sixth day post-infection, the treated wounds were significantly smaller than untreated wounds. A complete healing was shown by the 12th day after infection. Furthermore, our cytotoxicity results showed a cytotoxic effect of juniper EO MNDs on epithelial cells, which explained the faster wound healing in rats. Our study showed that juniper EO MNDs represent a novel strategy in EO delivery with minimal invasion. Juniper EO MNDs demonstrated significant antimicrobial activity against both the bacterial strains Pseudomonas aeruginosa and Staphylococcus aureus and against one fungal strain, Candida albicans. Finally, application of juniper EO MNDs exerted promising activity in the treatment and healing of wound infection.

A wearable self-powered microneedle system based on conductive drugs for infected wound healing: A new electrical stimulation delivery strategy

Electrical stimulation from wearable triboelectric nanogenerators is promising for wound treatment, but has limitations in healing infected wounds due to its restricted bactericidal efficacy. While combining triboelectric nanogenerators with antibacterial drugs is an effective approach, it faces challenges such as drug-loading content, patient compliance, and biosafety. Here, a wearable, self-powered microneedle system based on conductive drugs is developed for infected wounds through antimicrobial treatment and electrically stimulated tissue repair, in which the electrical stimulation is conducted by the designed drugs. The drug is synthesized through covalent bonding between levofloxacin and carbon quantum dots, eliminating bacteria effectively and endowing the microneedle patch with excellent conductivity. The electrical stimulation from a triboelectric nanogenerator delivered to the wound tissue promotes cell migration, cell proliferation, and collagen deposition. Infected-wound mice models demonstrate that the synergistic action of drugs and electrical stimulation in this system is more effective in promoting the healing of wounds than the sole application of either electrical stimulation or drugs. This study presents an innovative strategy for the treatment of infected wounds and paves the way for new approaches in wearable electronic devices for wound therapy.

Fucoidan-coated cotton dressing functionalized with biomolecules capped silver nanoparticles (LB-Ag NPs–FN–OCG) for rapid healing therapy of infected wounds

The colonization of pathogenic microbes poses a significant clinical barrier that hinders the physiological wound-healing process. Addressing this challenge, we developed a novel wound dressing using a modified cotton gauze dressing coated with fucoidan and functionalized with silver nanoparticles (LB-Ag NPs–FN–OCG) for the rapid treatment of infected wounds. Firstly, phytochemical-capped LB-Ag NPs were synthesized and characterized using high performance liquid chromatography (HPLC), transmission electron microscopy (TEM), and zeta potential analysis. Secondly, different concentrations of LB-Ag NPs (0.1%–1%) were functionalized into FN-OCG to identify appropriate concentrations that were non-toxic with superior antibacterial activities. Screening assays, including antibacterial, hemolysis, chick chorioallantoic membrane (CAM) assay, and cytotoxicity assay, revealed that LB-Ag NPs (0.5%)–FN–OCG were non-toxic and demonstrated greater efficiency in inhibiting bacterial pathogens (Escherichia coli, Salmonella enterica, Staphylococcus aureus, and Listeria monocytogenes) and promoting fibroblast cell (NIH3T3) migration. In vivo assays revealed that LB-Ag NPs (0.5%)–FN–OCG treatment exhibited excellent wound healing activity (99.73 ± 0.01%) compared to other treatments by inhibiting bacterial colonization, maintaining the blood parameters, developing granulation tissue, new blood vessels, and collagen deposition. Overall, this study highlights that LB-Ag NPs (0.5%)–FN–OCG serve as a antibacterial wound dressing for infected wound healing applications.

Novel lactoferrin-conjugated gallium complex to treat Pseudomonas aeruginosa wound infection

Pseudomonas aeruginosa is one of the leading causes of opportunistic infections such as chronic wound infection that could lead to multiple organ failure and death. Gallium (Ga3+) ions are known to inhibit P. aeruginosa growth and biofilm formation but require carrier for localized controlled delivery. Lactoferrin (LTf), a two-lobed protein, can deliver Ga3+ at sites of infection. This study aimed to develop a Ga-LTf complex for the treatment of wound infection. The characterisation of the Ga-LTf complex was conducted using differential scanning calorimetry (DSC), Infra-Red (FTIR) and Inductive Coupled Plasma Optical Emission Spectrometry (ICP-OES). The antibacterial activity was assessed by agar disc diffusion, liquid broth and biofilm inhibition assays using the colony forming units (CFUs). The healing capacity and biocompatibility were evaluated using a P.aeruginosa infected wound in a rat model. DSC analyses showed thermal transition consistent with apo-lactoferrin; FTIR confirmed the complexation of gallium to lactoferrin. ICP-OES confirmed the controlled local delivery of Ga3+. Ga-LTf showed a 0.57 log10 CFUs reduction at 24 h compared with untreated control in planktonic liquid broth assay. Ga-LTf showed the highest antibiofilm activity with a 2.24 log10 CFUs reduction at 24 h. Furthermore, Ga-LTf complex is biocompatible without any adverse effect on brain, kidney, liver and spleen of rats tested in this study. Ga-LTf can be potentially promising novel therapeutic agent to treat pathogenic bacterial infections.

A smart sensor for monitoring antimicrobial interventions in wound infections

Effective therapeutic monitoring of wound infections is crucial for wound care. We explore a novel approach using a previously described 3D-printed, colourimetric indicator to non-invasively monitor antimicrobial interventions in wound infection. The indicator contains a pH-sensitive dye which detects carbon dioxide production from wound pathogens by changing colour from blue to yellow. The sensor accurately reported the minimum inhibitory concentration of antibiotic against Pseudomonas aeruginosa in a sealed 96-well plate. Subinhibitory antibiotic concentrations resulted in the sensor changing colour, whilst remaining blue for inhibitory concentrations. The sensor was applied to a porcine skin wound model with Pseudomonas aeruginosa biofilms, testing several antimicrobial treatments: antibiotic monotherapy, phage monotherapy, and a combination of both. After treatment, the sensor, sealed with the wound, enabled visual monitoring of antimicrobial efficacy. Through comparing post-treatment bioburden and sensor response, greater log-fold reductions in P. aeruginosa following antimicrobial treatment correlated with longer sensor response times. Sensors monitoring unsuccessfully treated biofilms changed colour, while those treated at or above the minimum biofilm eradication concentration elicited no colour change, indicating P. aeruginosa eradication. This sensor holds promise for monitoring wound infection treatment efficacy, improving patient outcomes, and promoting undisturbed wound healing as a non-invasive point-of-care tool.

Exudate-Induced Gelatinizable Nanofiber Membrane with High Exudate Absorption and Super Bactericidal Capacity for Bacteria-Infected Wound Management.

Invasion of bacteria and continuous oozing of exudate are significant causes of interference with the healing of infected wounds. Therefore, an exudate-induced gelatinizable and near-infrared (NIR)-responsive nanofiber membrane composed of polyvinyl alcohol (PVA), carboxymethyl chitosan (CMC), and Fe-doped phosphomolybdic acid (Fe-PMA) with exceptional exudate absorption capacity and potent bactericidal efficacy is developed and denoted as the PVA-FP-CMC membrane. After absorbing exudate, the fiber membrane can transform into a hydrogel membrane, forming coordination bonds between the Fe-PMA and CMC. The unique exudate-induced gelation process imparts the membrane with high exudate absorption and retention capability, and the formed hydrogel also traps the bacteria that thrive in the exudate. Moreover, it is discovered for the first time that the Fe-PMA exhibits an enhanced photothermal conversion capability and photocatalytic activity compared to the PMA. Therefore, the presence of Fe-PMA provides the membrane with a photothermal and photodynamic therapeutic effect for killing bacteria. The PVA-FP-CMC membrane is proven with a liquid absorption ratio of 520.7%, a light-heat conversion efficiency of 41.9%, high-level generation of hydroxyl radical (•OH) and singlet oxygen (1O2), and a bacterial killing ratio of 100% for S. aureus and 99.6% for E. coli. The treatment of infected wounds on the backs of rats further confirms the promotion of wound healing by the PVA-FP-CMC membrane with NIR irradiation. Overall, this novel functional dressing for the synergistic management of bacteria-infected wounds presents a promising therapeutic strategy for tissue repair and regeneration.

Treatment of wound infections linked to neurosurgical implants.

As neurosurgery has advanced technologically, more and more neurosurgical implants are being employed on an aging patient population with several comorbidities. As a result, there is a steady increase in the frequency of infections linked to neurosurgical implants, which causes serious morbidity and mortality as well as abnormalities of the skull and inadequate brain protection. We discuss infections linked to internal and external ventricular and lumbar cerebrospinal fluid drainages, neurostimulators, craniotomies, and cranioplasty in this article. Biofilms, which are challenging to remove, are involved in all implant-associated illnesses. It takes a small quantity of microorganisms to create a biofilm on the implant surface. Skin flora bacteria are implicated in the majority of illnesses. Microorganisms that cause disruptions in wound healing make their way to the implant either during or right after surgery. In about two thirds of patients, implant-associated infections manifest early (within the first month after surgery), whereas the remaining infections present later as a result of low-grade infections or by direct extension from adjacent infections (per continuitatem) to the implants due to soft tissue damage. Except for ventriculo-atrial cerebrospinal fluid shunts, neurosurgical implants are rarely infected by the haematogenous route. This research examines established and clinically validated principles that are applicable to a range of surgical specialties using implants to treat biofilm-associated infections in orthopaedic and trauma cases. Nevertheless, there is little evidence and no evaluation in sizable patient populations to support the success of this extrapolation to neurosurgical patients. An optimal microbiological diagnostic, which includes sonicating removed implants and extending culture incubation times, is necessary for a positive result. Additionally, a strategy combining surgical and antibiotic therapy is needed. Surgical procedures involve a suitable debridement along with implant replacement or exchange, contingent on the biofilm's age and the state of the soft tissue. A protracted biofilm-active therapy is a component of antimicrobial treatment, usually lasting 4-12 weeks. This idea is appealing because it allows implants to be changed or kept in place for a single surgical procedure in a subset of patients. This not only enhances quality of life but also lowers morbidity because each additional neurosurgical procedure increases the risk of secondary complications like intracerebral bleeding or ischemia.

Development of an In Situ Photo-Crosslinking Antimicrobial Collagen Hydrogel for the Treatment of Infected Wounds.

Antimicrobial hydrogels have received considerable attention in the treatment of bacteria-infected wounds. Herein, we develop a neutral, soluble collagen via modification with maleic anhydride, serving as a hydrogel precursor. Maleic anhydride-modified collagen (ColME) could form a gel after exposure to UV light and be loaded with the antimicrobial agents, nisin and levofloxacin, to acquire antimicrobial ability. The ColME hydrogel containing nisin and levofloxacin had good cytocompatibility and effectively killed pathogenic bacterial strains, such as Escherichia coli and Staphylococcus aureus. The antimicrobial ColME hydrogels effectively supported the healing of a full-thickness skin wound infected with S. aureus in a mouse model. Our results demonstrate the potential of antimicrobial hydrogels as effective wound dressings via in situ photogelation for the healing of infected wounds.