Intramolecular Hydrogen Bonds Assisted Construction of Planar Tricyclic Structures for Insensitive and Highly Thermostable Energetic Materials.

Safety is fundamental for the practical development and application of energetic materials. Three tricyclic energetic compounds, namely, 1,3-di(1H-tetrazol-5-yl)-1H-1,2,4-triazol-5-amine (ATDT), 5'-nitro-3-(1H-tetrazol-5-yl)-2'H-[1,3'-bi(1,2,4-triazol)]-5-amine (ATNT), and 1-(3,4-dinitro-1H-pyrazol-5-yl)-3-(1H-tetrazol-5-yl)-1H-1,2,4-triazol-5-amine (ATDNP), were effectively synthesized through a simple two-step synthetic route. The introduction of intramolecular hydrogen bonds resulted in excellent molecular planarity for the three new compounds. Additionally, they exhibit regular crystal packing, leading to numerous intermolecular hydrogen bonds and π-π interactions. Benefiting from planar tricyclic structural features, ATDT, ATNT, and ATDNP are insensitive (IS > 60 J, FS = 360 N) when exposed to external stimuli. Furthermore, ATNT (Td = 361.1 °C) and ATDNP (Td = 317.0 °C) exhibit high decomposition temperatures and satisfying detonation performance. The intermolecular hydrogen bonding that produced this planar tricyclic molecular structure serves as a model for the creation of innovative multiple heterocycle energetic materials with excellent stability.

A new dressing system for accelerating wound recovery after primary total knee arthroplasty: a feasibility study.

PURPOSE: Currently, postoperative wound infection and poor healing of total knee arthroplasty have been perplexing both doctors and patients. We hereby innovatively invented a new dressing system to reduce the incidence of postoperative wound complications. METHODS: We enrolled 100 patients who received primary unilateral total knee arthroplasty and then applied the new dressing system. The data collected included the number of dressing changes, postoperative hospital stay, Visual Analogue Scale score (VAS), the Knee Society Score (KSS), the Knee Injury and Osteoarthritis Outcome Score (KOOS), ASEPSIS scores, The Stony Brook Scar Evaluation Scale (SBSES), wound complications, dressing cost, the frequency of shower and satisfaction. Subsequently, a statistical analysis of the data was performed. RESULTS: Our findings demonstrated the average number of postoperative dressing changes was 1.09 ± 0.38, and the average postoperative hospital stay was 3.72 ± 0.98 days. The average cost throughout a treatment cycle was 68.97 ± 12.54 US dollars. Collectively, the results of VAS, KSS, and KOOS revealed that the pain and function of patients were continuously improved. The results of the four indexes of the ASEPSIS score were 0, whereas the SBSES score was 3.58 ± 0.52 and 4.69 ± 0.46 at two weeks and one month after the operation, respectively. We observed no wound complications until one month after the operation. Remarkably, the satisfaction rate of the patients was 91.85 ± 4.99% one month after the operation. CONCLUSION: In this study, we invented a new dressing system for surgical wounds after total knee arthroplasty and further confirmed its clinical feasibility and safety. CHINESE CLINICAL TRIAL REGISTRY: ChiCTR2000033814, Registered 13/ June/2020.

Film dressings from Thai mango seed kernel extracts versus nanocrystalline silver dressings in antibacterial properties.

Introduction: The extract from the Mango Seed Kernel (MSK) has been documented to exhibit antibacterial activity against Gram-positive and Gram-negative bacteria, including Staphylococcus aureus and Pseudomonas aeruginosa. This suggests that biomaterials containing MSK extract could be a viable alternative to conventional wound treatments, such as nanocrystalline silver dressings. Despite this potential, there is a notable gap in the literature regarding comparing the antibacterial effectiveness of MSK film dressings with nanocrystalline silver dressings. This study aimed to develop film dressings containing MSK extract and evaluate their antibacterial properties compared to nanocrystalline silver dressings. Additionally, the study aimed to assess other vital physical properties of these dressings critical for effective wound care. Materials and methods: We prepared MSK film dressings from two cultivars of mango from Thailand, 'Chokanan' and 'Namdokmai'. The inhibition-zone method was employed to determine the antibacterial property. The morphology and chemical characterization of the prepared MSK film dressings were examined with scanning electron microscopy (SEM) and Fourier-Transform Infrared Spectroscopy (FTIR), respectively. The absorption of pseudo-wound exudate and water vapor transmission rate (WVTR) of film dressings were evaluated. Results: The results showed that 40% of MSKC film dressing had the highest inhibition zone (20.00 ± 0.00 mm against S. aureus and 17.00 ± 1.00 mm against P. aeruginosa) and 20%, 30%, and 40% of MSKC and MSKN film dressings had inhibition zones similar to nanocrystalline silver dressing for both S. aureus and P. aeruginosa (p > 0.05). In addition, all concentrations of the MSK film dressings had low absorption capacity, and Chokanan MSK (MSKC) film dressings had a higher WVTR than Namdokmai MSK (MSKN) film dressings. Conclusion: 20%, 30%, and 40% of MSK film dressing is nearly as effective as nanocrystalline silver dressing. Therefore, it has the potential to be an alternative antibacterial dressing and is suitable for wounds with low exudate levels.

Accuracy, Repeatability, and Reproducibility of a Hand-Held Structured-Light 3D Scanner across Multi-Site Settings in Lower Limb Prosthetics.

The aim of this work was to assess the accuracy, repeatability, and reproducibility of a hand-held, structured-light 3D scanner (EINScan Pro 2X Plus with High Definition Prime Pack, SHINING 3D Tech. Co., Ltd., Hangzhou, China), to support its potential use in multi-site settings on lower limb prosthetics. Four limb models with different shapes were fabricated and scanned with a metrological 3D scanner (EINScan Laser FreeScan 5X, SHINING 3D Tech. Co., Ltd., Hangzhou, China) by a professional operator (OP0). Limb models were then mailed to three sites where two operators (OP1, OP2) scanned them using their own structured-light 3D scanner (same model). OP1 scanned limb models twice (OP1-A, OP1-B). OP0, OP1-A, and OP2 scans were compared for accuracy, OP1-A and OP1-B for repeatability, and OP1-A and OP2 for reproducibility. Among all comparisons, the mean radial error was <0.25 mm, mean angular error was <4°, and root mean square error of the radial distance was <1 mm. Moreover, limits of agreement were <3.5% for perimeters and volumes. By comparing these results with respect to clinically-relevant thresholds and to the literature available on other 3D scanners, we conclude that the EINScan Pro 2X Plus 3D Scanner with High Definition Prime Pack has good accuracy, repeatability, and reproducibility, supporting its use in multi-site settings.

Recent Advances in the Synthesis of the Marine-Derived Alkaloid Fascaplysin and Its Metabolites Homofascaplysins A-C.

The fascaplysin and homofascaplysin class of marine natural products has a characteristic 12H-pyrido[1,2-a:3,4-b']diindole pentacyclic structure. Fascaplysin was isolated in 1988 from the marine sponge Fascaplysinopsis bergquist sp. The analogs of fascaplysin, such as homofascaplysins A, B, and C, were discovered late in the Fijian sponge F. reticulate, and also have potent antimicrobial activity and strong cytotoxicity against L-1210 mouse leukemia. In this review, the total synthesis of fascaplysin and its analogs, such as homofascaplysins A, B, and C, will be reviewed, which will offer useful information for medicinal chemistry researchers who are interested in the exploration of marine alkaloids.

The frictional energy absorber effectiveness and its impact on the pressure ulcer prevention performance of multilayer dressings.

Pressure ulcers including heel ulcers remain a global healthcare concern. This study comprehensively evaluates the biomechanical effectiveness of the market-popular ALLEVYN® LIFE multilayer dressing in preventing heel ulcers. It focuses on the contribution of the frictional sliding occurring between the non-bonded, fully independent layers of this dressing type when the dressing is protecting the body from friction and shear. The layer-on-layer sliding phenomenon, which this dressing design enables, named here the frictional energy absorber effectiveness (FEAE), absorbs approximately 30%-45% of the mechanical energy resulting from the foot weight, friction and shear acting to distort soft tissues in a supine position, thereby reducing the risk of heel ulcers. Introducing the novel theoretical FEAE formulation, new laboratory methods to quantify the FEAE and a review of relevant clinical studies, this research underlines the importance of the FEAE in protecting the heels of at-risk patients. The work builds on a decade of research published by our group in analysing and evaluating dressing designs for pressure ulcer prevention and will be useful for clinicians, manufacturers, regulators and reimbursing bodies in assessing the effectiveness of dressings indicated or considered for prophylactic use.

The hemostatic and comforting effects of oral adhesive bandages in tooth extraction: a randomized controlled clinical study.

OBJECTIVES: To compare oral adhesive bandages with the classic compression method and evaluate the clinical efficacy of this wound dressing material in improving postoperative comfort, wound healing, and hemostasis in tooth extraction. MATERIALS AND METHODS: The study was designed as a randomized controlled clinical trial. A total of 120 patients were recruited and randomly assigned to the study group and the control group. In the study group, oral adhesive bandages were used as wound dressing. In the control group, patients bit on cotton balls and gauze, as usual. Hemorrhage, comfort, and healing levels were evaluated at postoperative 1 h, 24 h, and 7 days. The adhesion time of the oral adhesive bandages was also recorded. RESULTS: The average adhesion time of the oral adhesive bandages was 26.6 h. At postoperative 1 and 24 h, the hemostatic levels of the oral adhesive bandage group were significantly higher than those of the control group. The oral adhesive bandage group also reported significantly higher comfort scores than the control group. Both groups had similar healing levels and side effects. But the mean score for wound healing was slightly higher in the oral adhesive bandage group. CONCLUSIONS: Oral adhesive bandages were more effective than cotton balls and gauze in providing hemostatic and comfort effects on extraction wounds. CLINICAL RELEVANCE: Oral adhesive bandages possess clinical value in the management of extraction wounds.

Use of person-centred music to manage wound dressing-related pain: a mixed method case study.

OBJECTIVE: To determine whether person-centred music (PCMusic) contributes to reducing pain during painful leg ulcer dressing change procedures indicated by: decreased levels of indicators related to stress; decreased pain scores; and a more favourable treatment climate during the dressing change procedure. METHOD: A case study of a 51-year-old female patient with chronic inherited disease weakening her connective tissues. Quantitative data entailed temporal measurements of stress indicators including: heart pulse rate; oxygen saturation (SpO2); saliva cortisol; and a visual analogue scale (VAS). Qualitative data comprised phenomenological treatment descriptions and patient/licensed practical nurse (LPN) questionnaires. RESULTS: The patient's body temperature remained steady throughout all treatments. Blood pressure was excluded due to missing data. No significant pulse rate differences in relation to music/no music could be observed during treatment. Comparing PCMusic to the patient's own other music (POOM), the pulse rate was greater in both magnitude and variation when the patient listened to POOM. Oxygen saturation showed no significant difference between PCMusic and music/no music. No significant difference was observed pre-/post-debridement with music. Similarly, no significant difference was observed pre-/post-debridement with no music. Treatment with no music showed the highest VAS score; PCMusic treatments had the lowest scores. Qualitative data showed that both patient and LPNs found that PCMusic decreased pain during dressing change. CONCLUSION: The results of this case study indicate that PCMusic is a suitable complementary treatment to decrease patient pain. Patients' general health status is important when using quantitative stress/pain marker measurements. For cohort selection in future studies, we suggest healthy patients undergoing slightly painful or unpleasant treatments, patients in postoperative care and obstetric care.

Changes in wound symptoms and quality of life of patients with newly diagnosed malignant fungating wounds.

OBJECTIVE: This study examined changes in wound symptoms and the health-related quality of life (HRQoL) of patients with newly diagnosed malignant fungating wounds, and explored the factors that impacted the changes in HRQoL. METHOD: This prospective longitudinal study included patients from three hospitals in China who had been diagnosed with malignant fungating wounds. Questionnaires were used to assess patients' HRQoL and their wound symptoms at the time of diagnosis (T0), as well as at one, three and six (T1, T2 and T3, respectively) months following the treatment period. Factors related to changes in HRQoL were analysed using generalised estimating equation models. RESULTS: A total of 162 patients were included in the study. The patients reported low overall HRQoL. In three health-related dimensions (functional status, social relations and mental health), patients reported lower functional status at the time of wound diagnosis (T0), which then increased slowly with treatment over time. A lower QoL was associated with odour, exudate, bleeding, pruritus, a low performance status and the need for the dressing of wounds. CONCLUSION: The HRQoL of patients with malignant fungating wounds exhibited significant changes across different periods. It is thus of great importance to formulate pragmatic, patient and family-centred palliative wound care management strategies.

Acute Burn Care.

LEARNING OBJECTIVES: After studying this article and viewing the videos, the participant should be able to: 1. Describe the current epidemiology of burn injuries. 2. Understand burn pathophysiology and perform a wound assessment. 3. Summarize the initial emergency management of a burn patient. 4. Calculate the anticipated fluid resuscitation requirements for a burn injury, and diagnose the complications of overresuscitation. 5. Describe the diagnosis and management of inhalation injury. 6. List the goals of wound care for superficial and deep burns, and describe the closed dressing technique. 7. Perform excision of a burn wound. 8. Compare various wound closure techniques using autografts and skin substitutes. SUMMARY: Plastic surgeons are essential members of the multidisciplinary burn team. Burn injuries remain common, and plastic surgeons have an opportunity to develop and innovate the field of acute burn care in light of workforce shortages. Burn pathophysiology is complex and dynamic, which informs the challenges encountered during the perioperative phase. Accurate burn wound assessment remains difficult, with implications for diagnosis and management. A systematic approach is required when stabilizing a major burn and/or inhalation injury with newly updated fluid resuscitation and triage guidelines. Wound care continues to evolve, with an emphasis on a closed dressing technique. For deeper burns, new surgical techniques are emerging for surgical débridement, along with improvements to traditional methods of tangential excision. Following excision, a number of established and novel techniques are available to close the wound with either autografts or skin substitutes.

Effect of dressing with different antiseptic agents on reproductive parameters in rats undergoing abdominal incision.

Antiseptic agents used in the postoperative period affect the functions of many tissues in the body, including the testicles. In this study, the effect of dressings administered with different antiseptic agents on testicular functions in rats that underwent abdominal incisions was investigated. A total of 48 Sprague-Dawley rats were used in the study. Each of the rats in the study group underwent a 4 cm-long skin and muscle operation. The incision was then stitched immediately. Antiseptics, hemp seed oil, hemp leaf oil, and cannabidiol oil were then administered to the rats for 10 days to provide antisepsis. The rats were sacrificed 24 hours after the last administration, and testicular tissues were removed. Testicular tissues were used for histopathological examination and biochemical analysis, while epididymal tissue was used for sperm analysis. According to the results, the MDA level in the antiseptic-administered group was higher than in the other experimental groups (p<0.05). Levels of SOD, CAT activities, and GSH content were found to be lower in the antiseptic group than in the hemp seed oil, hemp leaf oil, and cannabidiol oil groups (p<0.05). In testicular histology, the SEED group had the highest Johnsen score, and the antiseptic group had the lowest score (p<0.05). While JAK, P-JAK2, STAT3, PSTAT3, and NF-κB were generally higher in the antiseptic group compared to the other groups, they were lower in the SEED group. Additionally, sperm total motility rate and epididymal sperm density were highest in the SEED group (p<0.05). As a result, it was determined that cannabidiol seed oil had a good effect on testicular histology and sperm quality in male rats during the wound healing process.

A standardized wound infection model for antimicrobial testing of wound dressings in vitro.

To investigate the effectiveness of antimicrobial agents against wound infections, experiments using either 2D cultures with planktonic microorganisms or animal infection models are frequently carried out. However, the transferability of the results to human skin is limited by the lack of complexity of the 2D models or by the poor translation of the results from animal models. Hence, there is a need for wound infection models capable of assessing antimicrobial agents. In this study, an easily standardized wound infection model was established. This model consists of a mechanically wounded human skin model on a collagen matrix infected with various clinically relevant bacteria. Infection of the model led to recognition of the pathogens and induction of an inflammatory response. The untreated infection spread over time, causing significant tissue damage. By applying an antimicrobial-releasing wound dressing, the bacterial load could be reduced and the success of the treatment could be further measured by a decrease in the inflammatory reaction. In conclusion, this wound infection model can be used to evaluate new antimicrobial therapeutics as well as to study host-pathogen interactions.

An investigation of the antimicrobial efficacy of a nonwoven CMC PHMB dressing and the ability of the dressing to absorb wound slough.

OBJECTIVE: To conduct an in vitro investigation into the slough absorption and retention attributes of a gelling fiber dressing composed of CMC fibers and PHMB (Dressing A), and to assess its antimicrobial efficacy under compression. MATERIALS AND METHODS: Dressing A is indicated for use with secondary dressings or bandaging, and conditions that replicate this compression element were applied. Dressing A was compared with 5 other dressings. Antimicrobial efficacy testing was conducted over a 7-day challenge period. RESULTS: Dressing A absorbed an average of 33 g/100 cm2 per sample of viscous solution, 28% more than the other dressings tested. A greater than or equal to 6-log reduction of all microorganisms tested was achieved within 168 hours with Dressing A. CONCLUSION: The CMC PHMB gelling fiber dressing is able to absorb and retain viscous solutions (simulated slough). The antimicrobial efficacy of the dressing under compression was demonstrated by total eradication of all microorganisms tested.

Short macrocyclic peptides in sponge genomes.

Sponges (Porifera) contain many peptide-specialized metabolites with potent biological activities and significant roles in shaping marine ecology. It is well established that symbiotic bacteria produce bioactive "sponge" peptides, both on the ribosome (RiPPs) and nonribosomally. Here, we demonstrate that sponges themselves also produce many bioactive macrocyclic peptides, such as phakellistatins and related proline-rich macrocyclic peptides (PRMPs). Using the Stylissa carteri sponge transcriptome, methods were developed to find sequences encoding 46 distinct RiPP-type core peptides, of which ten encoded previously identified PRMP sequences. With this basis set, the genome and transcriptome of the sponge Axinella corrugata was interrogated to find 35 PRMP precursor peptides encoding 31 unique core peptide sequences. At least 11 of these produced cyclic peptides that were present in the sponge and could be characterized by mass spectrometry, including stylissamides A-D and seven previously undescribed compounds. Precursor peptides were encoded in the A. corrugata genome, confirming their animal origin. The peptides contained signal peptide sequences and highly repetitive recognition sequence-core peptide elements with up to 25 PRMP copies in a single precursor. In comparison to sponges without PRMPs, PRMP sponges are incredibly enriched in potentially secreted polypeptides, with >23,000 individual signal peptide encoding genes found in a single transcriptome. The similarities between PRMP biosynthetic genes and neuropeptides in terms of their biosynthetic logic suggest a fundamental biology linked to circular peptides, possibly indicating a widespread and underappreciated diversity of signaling peptide post-translational modifications across the animal kingdom.

Modified in-vitro AATCC-100 procedure to measure viable bacteria from wound dressings.

Chronic wounds are reoccurring healthcare problems in the United States and cost up to $50 billion annually. Improper wound care results in complications such as wound debridement, surgical amputation, and increased morbidity/ mortality due to opportunistic infections. To eliminate wound infections, many antimicrobial dressings are developed and submitted to FDA for evaluation. AATCC-100 is a standard method widely used to evaluate cloth wound dressings. This method, requires enrichment, followed by culturing to measure the concentration of culturable organisms; a caveat to this method could result in neglected viable but nonculturable (VBNC) bacteria and overestimate the antimicrobial properties of wound dressings. Therefore, the objectives of this study were to assess this accepted protocol with quantitative real-time polymerase chain reaction (qRT-PCR), to measure time dependent antimicrobial efficacy of wound dressing, and to examine for potential viable bacteria but non-culturable as compared with traditional plating methods. The test organisms included opportunistic pathogens: Pseudomonas aeruginosa (ATCC 15692) and Staphylococcus aureus (ATCC 43300). To mimic a wound dressing environment, samples of commercially available wound dressings (McKesson Inc.) with silver ion (positive control) and dressings without silver ion (positive control) were assessed under sterile conditions. All samples were examined by the original protocol (the extended AATCC-100 method) and qRT-PCR. The expression of specific housekeeping genes was measured (proC for P. aeruginosa and 16s rRNA for S. aureus). Based on these tests, log reduction of experimental conditions was compared to identify time dependent and precise antimicrobial properties from wound dressing samples. These results showed antimicrobial properties of wound dressings diminished as incubation days are increased for both methods from day 1 PCR result of 4.31 ± 0.54 and day 1 plating result of 6.31 ± 3.04 to day 3 PCR result of 1.22 ± 0.97 and day 3 plating result of 5.89 ± 2.41. These results show that data from qRT-PCR generally produced lower standard deviation than that of culture methods, hence shown to be more precise. Complementary parallel analysis of samples using both methods better characterized antimicrobial properties of the tested samples.

The Breakfast and Dressing Conflict Task: Preliminary Evidence of Its Validity to Measure Online Self-Awareness After Acquired Brain Injury.

IMPORTANCE: Impaired self-awareness (SA) of deficits after an acquired brain injury (ABI) severely affects patients' independence in activities of daily living (ADLs). However, any assessment tool permits an exhaustive evaluation of SA in the context of ADLs. OBJECTIVE: To study the validity of the Breakfast and Dressing Conflict Task (BD Conflict Task) to assess online SA (awareness of performance in the context of a given task) in patients with ABI; to study its interactions with offline SA (general awareness); and to test the validity of a simplified measure of performance monitoring, the ADL Conflict-Monitoring Index. DESIGN: Convergent validity and correlational study. SETTING: Research laboratory, hospitals, and homes. PARTICIPANTS: Thirty patients with ABI and 28 neurologically healthy controls. OUTCOMES AND MEASURES: Using the BD Conflict Task, measures of emergent awareness, self-regulation, anticipatory awareness, and self-evaluation were assessed and their convergent validity and relationship with offline SA were analyzed. The ADL Conflict-Monitoring Index was calculated, and its convergent validity was tested. RESULTS: The online SA variables of the BD Conflict Task showed convergent validity with traditional online SA measures. Offline SA correlated with emergent and anticipatory awareness in the Breakfast Task. The ADL Conflict-Monitoring Index proved to be a valid measure of patients' performance monitoring. CONCLUSIONS AND RELEVANCE: These preliminary findings suggest that the BD Conflict Task is a valid tool to assess online SA in patients with ABI and provide further understanding of the online SA-offline SA interaction. Furthermore, the ADL Conflict-Monitoring Index may be a valid and easy-to-use monitoring measure in clinical settings. Plain-Language Summary: Patients with acquired brain injury (ABI) and reduced awareness of their cognitive deficits face problems performing activities of daily living (ADLs) and may show signs of unsafe behaviors. Being aware of one's own abilities involves anticipating problems before starting a task, detecting and correcting errors during the task, and evaluating performance afterward. This study provides preliminary validity for the Breakfast and Dressing Conflict Task, a new tool that assesses aspects of self-awareness simultaneously in the context of familiar and significant ADLs. Furthermore, the tool simplifies the assessment of detecting and correcting errors with an easy-to-use index, making it suitable for use in clinical settings.

Physical characterization, biocompatibility, and antimicrobial activity of polyvinyl alcohol/sodium alginate blend doped with TiO2 nanoparticles for wound dressing applications.

The ability of wound dressing materials to tackle skin pathogens colonization that is associated with open wound infections is limited. Recently, green-synthesized metal oxide nanoparticles has received a lot of attention to overcome this limitation. However, titanium dioxide nanoparticles (TiO2-NPs) exhibit exceptional antibacterial properties. In this work, several concentrations (0, 1, 3, and 5 wt.%) of TiO2 NPs prepared using Aloe vera leaf extract were added to a blend of polyvinyl alcohol and sodium alginate (PVA:SA). This nanocomposite was designed to enhance the healing process of wounds. The interaction between the PVA:SA composite and the TiO2 NPs was confirmed by FTIR. The thermal behavior of the nanocomposite films was investigated using DSC and TGA. The experimental results indicate that the glass transition temperatures of the nanocomposites increased by increasing the added amount of TiO2 NPs to be 53.7 °C (1 wt.%), 55.8 °C (3 wt.%), and 60.6 °C (5 wt.%), which were consistently lower than the glass transition temperature of the matrix material (69.6 °C). The Dynamic Mechanical Analysis was examined. The nanocomposite doped with 5 wt.% of TiO2 NPs detected a high storage modulus (21.6 × 108). Based on swelling and degradation studies, the prepared PVA:SA:TiO2 nanocomposite films have an excellent swelling rate, and the inclusion of TiO2 NPs increases the stability of the polymeric matrix. The PVA:SA:TiO2 nanocomposite films exhibited a superior antibacterial efficacy against Gram-positive bacteria such as Bacillus cereus and Staphylococcus aureus, compared to their effectiveness against Gram-negative bacteria like Escherichia coli. Moreover, the nanocomposite films were biocompatible with Human Skin Fibroblast. Therefore, the developed PVA:SA:TiO2 nanocomposite films suit wound dressing applications.

Cytotoxicity and concentration of silver ions released from dressings in the treatment of infected wounds: a systematic review.

Introduction: Silver-releasing dressings are used in the treatment of infected wounds. Despite their widespread use, neither the amount of silver released nor the potential in vivo toxicity is known. The aim of this study was to evaluate the cytotoxic effects and the amount of silver released from commercially available dressings with infected wounds. Methods: The review was conducted according to the PRISMA statement. The Web of Science, PubMed, Embase, Scopus, and CINAHL databases were searched for studies from 2002 through December 2022. The criteria were as follows: population (human patients with infected wounds); intervention (commercial dressings with clinical silver authorized for use in humans); and outcomes (concentrations of silver ions released into tissues and plasma). Any study based on silver-free dressings, experimental dressings, or dressings not for clinical use in humans should be excluded. According to the type of study, systematic reviews, experimental, quasi-experimental, and observational studies in English, Spanish, or Portuguese were considered. The quality of the selected studies was assessed using the JBI critical appraisal tools. Studies that assessed at least 65% of the included items were included. Data were extracted independently by two reviewers. Results: 740 articles were found and five were finally selected (all of them quasi-experimental). Heterogeneity was found in terms of study design, application of silver dressings, and methods of assessment, which limited the comparability between studies. Conclusion: In vivo comparative studies of clinical dressings for control of infection lack a standardized methodology that allows observation of all the variables of silver performance at local and systemic levels, as well as evaluation of its cytotoxicity. It cannot be concluded whether the assessed concentrations of released silver in commercial dressings for the topical treatment of infected wounds are cytotoxic to skin cells. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022351041, PROSPERO [CRD42022351041].

Variable effects of exposure to ionic silver in wound-associated bacterial pathogens.

Silver compounds are used in wound dressings to reduce bioburden. Where infection is not rapidly resolved, bacteria may be exposed to sub-therapeutic concentrations of antimicrobials over prolonged periods of time. In this study, a panel of chronic wound bacteria, Pseudomonas aeruginosa (two strains), Staphylococcus aureus, and Escherichia coli, were exposed to silver nitrate on agar. Phenotypic characterization was achieved using broth microdilution sensitivity testing, a crystal violet biofilm assay, and a wax moth pathogenesis model. Repeated exposure to ionic silver did not result in planktonic phenotypic silver resistance in any of the test panels, although S. aureus demonstrated reversible increases in minimum bactericidal concentration. An ulcer-derived P. aeruginosa exhibited marked reductions in biofilm eradication concentration as well as significantly increased biofilm formation and wax moth killing when compared to the same progenitor. These changes were reversible, trending towards baseline measurements following 10 passages on silver-free media. Changes in virulence and biofilm formation in the other test bacteria were generally limited. In summary, phenotypic adaptation following exposure to ionic silver was manifested other than through changes in planktonic susceptibility. Significant changes in pseudomonas biofilm formation and sensitivity could have implications for wound care regimes and therefore warrant further investigation.

Optimization of emulsification conditions with rice bran concentrates for the preliminary formulation of potential vegan dressings and their characterization.

A fraction of rice bran (RB), generated during the brown rice polishing, is utilized to extract oil, resulting in defatted RB (DRB). The aim of this study was to optimize the emulsification conditions to enhance the value of this byproduct by formulating potential vegan dressings and characterizing them. Enzymatic hydrolysis of the starch present in DRB yields the DRB concentrate (DRBC). A central composite design was applied and the results were analyzed using response surface methodology to select optimal conditions for an oil-in-water emulsion formula. Two formulations were chosen: one corresponds to the optimal conditions, with 26.5% of oil and 73.5% of DRBC dispersion (eoptimal), and the other one with 21.7% of oil and 78.3% of dispersion (eED8). The eoptimal formulation exhibited significantly lower mean De Brouckere diameter (D4,3) value and higher viscosity when compared with eED8. For both emulsions, the particle size distribution and D4,3 remained unchanged during storage, whereas viscosity decreased, and backscattering (BS) increased. Initially, both emulsions exhibited solid viscoelastic behavior, which was partially lost during quiescent storage. The increase in BS was attributed to particle disaggregation, ultimately leading to the aforementioned change in rheological behavior. In conclusion, although the designed emulsions underwent microstructural changes, they were stable against gravitational separation. To improve stability during quiescent storage, it is suggested to incorporate a thickening agent. Hence, it is propose to procced with the development of a vegan dressing based on the eoptimal emulsion, as it exhibits superior physicochemical properties.