Mutational background influences P. aeruginosa ciprofloxacin resistance evolution but preserves collateral sensitivity robustness.

Collateral sensitivity is an evolutionary trade-off whereby acquisition of the adaptive phenotype of resistance to an antibiotic leads to the nonadaptive increased susceptibility to another. The feasibility of harnessing such a trade-off to design evolutionary-based approaches for treating bacterial infections has been studied using model strains. However, clinical application of collateral sensitivity requires its conservation among strains presenting different mutational backgrounds. Particularly relevant is studying collateral sensitivity robustness of already-antibiotic-resistant mutants when challenged with a new antimicrobial, a common situation in clinics that has hardly been addressed. We submitted a set of diverse Pseudomonas aeruginosa antibiotic-resistant mutants to short-term evolution in the presence of different antimicrobials. Ciprofloxacin selects different clinically relevant resistance mutations in the preexisting resistant mutants, which gave rise to the same, robust, collateral sensitivity to aztreonam and tobramycin. We then experimentally determined that alternation of ciprofloxacin with aztreonam is more efficient than ciprofloxacin­tobramycin alternation in driving the extinction of the analyzed antibiotic-resistant mutants. Also, we show that the combinations ciprofloxacin­aztreonam or ciprofloxacin­tobramycin are the most effective strategies for eliminating the tested P. aeruginosa antibiotic-resistant mutants. These findings support that the identification of conserved collateral sensitivity patterns may guide the design of evolution-based strategies to treat bacterial infections, including those due to antibiotic-resistant mutants. Besides, this is an example of phenotypic convergence in the absence of parallel evolution that, beyond the antibiotic-resistance field, could facilitate the understanding of evolution processes, where the selective forces giving rise to new, not clearly adaptive phenotypes remain unclear.

Cantharidin (1%), podophyllin (5%), and salicylic acid (30%) formulation in recalcitrant plantar warts: Analysis of 48 patients.

A plantar wart is a benign hyperplasia that appears on the feet due to the human papillomavirus (HPV). One method used for the treatment of recalcitrant plantar warts, those lasting over 2 years or persisting after at least two treatment attempts, is the cantharidin (1%), podophyllin (5%), and salicylic acid (30%) formulation, also known as the CPS formulation. Although this method is in use, there are few studies on it. This study's objective was to ascertain its cure rate. For this retrospective observational study, we reviewed the medical records of patients treated with the CPS formulation at a podiatric clinic specializing in plantar wart treatment. Our sample size was 48 subjects. The CPS formulation had a cure rate of 62.5%. Out of the cured patients, 86.67% (26/30) required one or two applications. There was no observable correlation (p > 0.05) between wart resolution and virus biotype, evolution time, patient's morphological and clinical attributes, location, number of warts, or preceding treatments. The CPS formulation presents a relatively high efficacy rate for treating recalcitrant HPV plantar warts. Still, additional studies are necessary to evaluate its safety and efficiency.

Diagnostic imaging of the diabetic foot: an EANM evidence-based guidance.

PURPOSE: Consensus on the choice of the most accurate imaging strategy in diabetic foot infective and non-infective complications is still lacking. This document provides evidence-based recommendations, aiming at defining which imaging modality should be preferred in different clinical settings. METHODS: This working group includes 8 nuclear medicine physicians appointed by the European Association of Nuclear Medicine (EANM), 3 radiologists and 3 clinicians (one diabetologist, one podiatrist and one infectious diseases specialist) selected for their expertise in diabetic foot. The latter members formulated some clinical questions that are not completely covered by current guidelines. These questions were converted into statements and addressed through a systematic analysis of available literature by using the PICO (Population/Problem-Intervention/Indicator-Comparator-Outcome) strategy. Each consensus statement was scored for level of evidence and for recommendation grade, according to the Oxford Centre for Evidence-Based Medicine (OCEBM) criteria. RESULTS: Nine clinical questions were formulated by clinicians and used to provide 7 evidence-based recommendations: (1) A patient with a positive probe-to-bone test, positive plain X-rays and elevated ESR should be treated for presumptive osteomyelitis (OM). (2) Advanced imaging with MRI and WBC scintigraphy, or [18F]FDG PET/CT, should be considered when it is needed to better evaluate the location, extent or severity of the infection, in order to plan more tailored treatment. (3) In a patient with suspected OM, positive PTB test but negative plain X-rays, advanced imaging with MRI or WBC scintigraphy + SPECT/CT, or with [18F]FDG PET/CT, is needed to accurately assess the extent of the infection. (4) There are no evidence-based data to definitively prefer one imaging modality over the others for detecting OM or STI in fore- mid- and hind-foot. MRI is generally the first advanced imaging modality to be performed. In case of equivocal results, radiolabelled WBC imaging or [18F]FDG PET/CT should be used to detect OM or STI. (5) MRI is the method of choice for diagnosing or excluding Charcot neuro-osteoarthropathy; [18F]FDG PET/CT can be used as an alternative. (6) If assessing whether a patient with a Charcot foot has a superimposed infection, however, WBC scintigraphy may be more accurate than [18F]FDG PET/CT in differentiating OM from Charcot arthropathy. (7) Whenever possible, microbiological or histological assessment should be performed to confirm the diagnosis. (8) Consider appealing to an additional imaging modality in a patient with persisting clinical suspicion of infection, but negative imaging. CONCLUSION: These practical recommendations highlight, and should assist clinicians in understanding, the role of imaging in the diagnostic workup of diabetic foot complications.

Transcriptomic profiling of an evolved Yarrowia lipolytica strain: tackling hexanoic acid fermentation to increase lipid production from short-chain fatty acids.

BACKGROUND: Short-chain fatty acids (SCFAs) are cost-effective carbon sources for an affordable production of lipids. Hexanoic acid, the acid with the longest carbon chain in the SCFAs pool, is produced in anaerobic fermentation of organic residues and its use is very challenging, even inhibiting oleaginous yeasts growth. RESULTS: In this investigation, an adaptive laboratory evolution (ALE) was performed to improve Yarrowia lipolytica ACA DC 50109 tolerance to high hexanoic acid concentrations. Following ALE, the transcriptomic analysis revealed several genetic adaptations that improved the assimilation of this carbon source in the evolved strain compared to the wild type (WT). Indeed, the evolved strain presented a high expression of the up-regulated gene YALI0 E16016g, which codes for FAT1 and is related to lipid droplets formation and responsible for mobilizing long-chain acids within the cell. Strikingly, acetic acid and other carbohydrate transporters were over-expressed in the WT strain. CONCLUSIONS: A more tolerant yeast strain able to attain higher lipid content under the presence of high concentrations of hexanoic acid has been obtained. Results provided novel information regarding the assimilation of hexanoic acid in yeasts.

Magnetoelastic Coupling Evidence by Anisotropic Crossed Thermal Expansion in Magnetocaloric RSrCoFeO6 (R = Sm, Eu) Double Perovskites.

Double perovskite oxides, characterized by their tunable magnetic properties and robust interconnection between the lattice and magnetic degrees of freedom, present an enticing foundation for advanced magnetic refrigeration materials. Herein, we delve into the influence of rare-earth elements on RSrCoFeO6 (R = Sm, Eu) disordered double perovskites by examining their structural, electronic, magnetic, and magnetocaloric properties. Temperature-dependent synchrotron X-ray diffraction analysis confirmed the stability of the orthorhombic phase (Pnma) across a wide temperature range. X-ray photoemission spectroscopy revealed that both Sm and Eu are in the 3+ state, whereas multiple states for Co2+/3+ and Fe3+/4+ are identified. The magnetic investigation and magnetocaloric effect (MCE) analysis brought to light the presence of a long-range antiferromagnetic (AFM) order with a second-order phase transition (SOPT) in both samples. The maximum magnetic entropy change ΔSMmax was approximately 0.9 J/kg K for both samples at applied field 0-7 T, manifesting prominently above Neel temperatures TN ≈ 93 K (Sm) and 84 K (Eu). Nevertheless, different relative cooling powers (RCP) of 112.6 J/kg (Sm) and 95.5 J/kg (Eu) were observed. A detailed analysis of the temperature-dependent lattice parameters shed light on a distinct magnetocaloric effect across the magnetic transition temperature, unveiling an anisotropic thermal expansion [αV = 1.41 × 10-5 K-1 (Sm) and αV = 1.54 × 10-5 K-1 (Eu)] wherein the thermal expansion axial ratio αbSm/αbEu = 0.61 became lower with increasing temperature, which suggests that the Eu sample experiences a greater thermal expansion in the b-axis direction. At the atomic bonding level, the evidence for magnetoelastic coupling around the magnetic transition temperatures TN was found through the anomalies along the average Co/Fe-O bond distance, formal valence, octahedral distortion, as well as an anisotropic lattice expansion.

Unveiling the Structural Properties, Optical Behavior, and Thermoelectric Performance of 2D CsSn2Br5 Halide Obtained by Mechanochemistry.

Metal halide perovskites with a two-dimensional structure are utilized in photovoltaics and optoelectronics. High-crystallinity CsSn2Br5 specimens have been synthesized via ball milling. Differential scanning calorimetry curves show melting at 553 K (endothermic) and recrystallization at 516 K (exothermic). Structural analysis using synchrotron X-ray diffraction data, collected from 100 to 373 K, allows for the determination of Debye model parameters. This analysis provides insights into the relative Cs-Br and Sn-Br chemical bonds within the tetragonal structure (space group: I4/mcm), which remains stable throughout the temperature range studied. Combined with neutron data, X-N techniques permit the identification of the Sn2+ lone electron pair (5s2) in the two-dimensional framework, occupying empty space opposite to the four Sn-Br bonds of the pyramidal [SnBr4] coordination polyhedra. Additionally, diffuse reflectance UV-vis spectroscopy unveils an indirect optical gap of approximately ∼3.3 eV, aligning with the calculated value from the B3LYP-DFT method (∼3.2 eV). The material exhibits a positive Seebeck coefficient as high as 6.5 × 104 µV K-1 at 350 K, which evolves down to negative values of -3.0 × 103 µV K-1 at 550 K, surpassing values reported for other halide perovskites. Notably, the thermal conductivity remains exceptionally low, between 0.32 and 0.25 W m-1 K-1.

Diagnostic Accuracy of Dermatoscopy Versus Microbiological Culture and Polymerase Chain Reaction in the Diagnosis of Onychomycosis: A Cross-Sectional Study.

BACKGROUND: Several clinical signs in dermatoscopy are very characteristic of onychomycosis and can be a quick complement for the diagnosis of onychomycosis. OBJECTIVES: The aim of this study was to evaluate the diagnostic accuracy of dermatoscopy compared to microbiological culture and polymerase chain reaction (PCR), as well as the clinical signs associated with onychomycosis. METHODS: The clinical signs of 125 patients were assessed cross-sectionally using dermatoscopy, and a positive or negative result was assigned. A sample was then taken for PCR and microbiological culture. RESULTS: Of the 125 patients, 69.6% (87/125) had positive results when both laboratory tests were combined. When they were not combined, the prevalence was lower at 48% (60/125) with PCR and at 43.2% (54/125) with culture. Furthermore, 76.8% (96/125) were classified as positive with dermatoscopy with a sensitivity of 1, a specificity of 0.76, positive predictive value of 0.91 and negative predictive value of 1 (with 95% confidence intervals). Of the 96 dermatoscopy-positive samples, 36 were negative with PCR (p < 0.001), 42 were negative with culture (p < 0.001) and nine were negative when both tests were combined (p < 0.001). Clinical signs that were significantly associated with the presence of onychomycosis were subungual hyperkeratosis (dermatoscopy: p = 0.004, odds ratio (OR) = 2.438; PCR + microbiological culture: p = 0.004, OR = 3.221), subungual detritus (p = 0.033, OR = 3.01, only with dermatoscopy) and dermatophytoma (dermatoscopy: p = 0.049, OR = 3.02; PCR + microbiological culture: p = 0.022, OR = 2.40). CONCLUSIONS: The results suggest that dermatoscopy is a good tool for the diagnosis of onychomycosis but should be used as a complementary test or for screening patients to be sampled for laboratory testing. The combination of the three tests can lead to a reduction of false-positive and false-negative clinical and laboratory results. This allows for early diagnosis and specific treatment based on test results.

Inter-observer reliability of the Onychomycosis Severity Index depending on clinical experience: A review of 50 cases.

BACKGROUND: Onychomycosis (ONM) is the most prevalent nail unit pathology, and its severity and monitoring are often based on the visual judgement of clinicians. OBJECTIVE: The objective of this study is to assess the reliability of the Onychomycosis Severity Index (OSI) classification when utilized by three clinicians with varying levels of clinical experience: an experienced podiatrist (with 5 years of experience), a moderately experienced podiatrist (with 2 years of experience) and an inexperienced podiatrist (a recent graduate familiar with the OSI classification but lacking clinical experience). Additionally, we compared the severity assessments made through visual inspection with those determined using the OSI by different clinicians. METHODS: We evaluated reliability using the intraclass correlation index (ICC), analysing 50 images of ONM. RESULTS: The OSI demonstrated a very high level of reliability (ICC: 0.889) across clinicians, irrespective of their experience levels. Conversely, a statistically significant increase in severity was observed when comparing visual assessments with the OSI (p < .001) for ONM severity evaluation. CONCLUSION: The OSI proves to be a reproducible classification system, regardless of the clinical experience of the practitioner employing it.

Evaluation of usability, adherence, and clinical efficacy of therapeutic footwear in persons with diabetes at moderate to high risk of diabetic foot ulcers: A multicenter prospective study.

OBJECTIVE: To evaluate therapeutic footwear expectations and usability of individuals with diabetes and foot complications. DESIGN: A prospective multicenter study was conducted on participants with a high risk of developing a diabetic foot ulcer. SETTING: Participants were enrolled in 11 different specialized diabetic foot units in Spain between March 2022 and June 2023. SUBJECTS: Patients with diabetes at moderate to high risk of foot ulceration receiving first therapeutic footwear prescription. INTERVENTIONS: All the patients included in the research were prescribed with their first pair of therapeutic footwear. MAIN MEASURES: Primary outcome measures were MOS-pre and MOS-post questionnaires evaluating use and usability of prescribed therapeutic footwear. Secondary outcome measures aimed to evaluate footwear clinical efficacy as ulceration rate and self-reported perceived walking distance per day. RESULTS: The use of therapeutic footwear exceeded the patient's pre-provision prediction of their anticipated use in 94% of people (n = 126). Based on the visual analogic satisfaction scale, the median satisfaction of daily wearing their therapeutic footwear was 7 points, Interquartile Range (IQR) [5-8.25]. During the follow-up period, 39 participants (29.1%) experienced diabetic foot ulcer. Perceived walking distance participants reported an improvement in their perceived walking ability during various daily life activities. CONCLUSIONS: Diabetes patients at moderate to high risk of diabetic foot ulcer improved their perception of walking ability after therapeutic footwear prescription. Adherence to the therapeutic footwear prescription resulted in less ulcerations.

Using patient-reported experiences to inform the use of foam dressings for hard-to-heal wounds: perspectives from a wound care expert panel.

Caring for patients with hard-to-heal (chronic) wounds requires a multifaceted approach that addresses their diverse needs, which can contribute to the complexity of care. Wound care providers must have a comprehensive understanding of the patient's comorbid conditions and psychosocial issues to provide personalised and effective treatment. Key quality indicators for effective wound care involves not only selecting appropriate local wound care products, such as foam dressings, but also addressing individual patient experiences of wound-related pain, odour, itch, excessive wound drainage, and self-care needs. The purpose of this review is to inculcate the wound care practice community, research scientists and healthcare industry with a sense of accountability in order to work collaboratively in addressing these unmet care needs.

Clinical efficacy and safety of a silver ion-releasing foam dressing on hard-to-heal wounds: a meta-analysis.

OBJECTIVE: Delayed or stalled healing in open wounds can result from persisting chronic inflammation related to infection and/or persistent bacterial colonisation and biofilm. Treatment of hard-to-heal wounds focuses on debridement and exudate management, but also on infection prevention and control. Silver dressings have been evaluated in randomised clinical trials (RCTs); this meta-analysis evaluated the efficacy and safety of a silver ion-releasing foam dressing (Biatain Ag; Coloplast A/S, Denmark) to treat hard-to-heal wounds. METHOD: Literature databases (PubMed and Cochrane Library) were searched for studies on silver ion-releasing foam dressings in the treatment of hard-to-heal wounds. Individual patient data from four RCTs were obtained and included in the meta-analysis. RESULTS: Findings showed that treatment with the silver ion-releasing foam dressing was associated with a significantly higher relative reduction in wound area after four (least squares-mean difference (LS-MD): -12.55%, 95% confidence interval (CI): (-15.95, -9.16); p<0.01) and six weeks of treatment (LS-MD: -11.94%, 95%CI: (-17.21, -6.68); p<0.01) compared with controls. Significant benefits were also observed for time to disappearance of odour (hazard ratio: 1.61, 95%CI: (1.31, 1.98); p<0.01), relative reduction of exudate (LS-MD: -5.15, 95%CI: (-7.36, -2.94); p<0.01), proportion of patients with periwound erythema (relative risk (RR): 0.81, 95%CI: (0.69; 0.94); p<0.01), and less pain at dressing removal (LS-MD: -0.35, 95%CI: (-0.63, -0.06); p=0.02). No differences regarding safety outcomes were identified. CONCLUSION: This meta-analysis has demonstrated beneficial outcomes and a good tolerability profile for silver ion-releasing foam dressings in the treatment of moderate-to-highly exuding wounds with delayed healing compared with control dressings.

TLC-NOSF dressings as a first-line local treatment of chronic wounds: a systematic review of clinical evidence.

OBJECTIVE: Several national and international guidelines recommend lipidocolloid technology with a nano-oligosaccharide factor (TLC-NOSF) dressings (UrgoStart dressing range, Laboratoires Urgo, France) for treating patients with chronic wounds. However, these dressings are still often reported as second-line options, potentially leading to loss of opportunity for patients and additional costs for payers. This review aimed to explore the reported wound healing and patient outcomes as well as the related costs when the dressings were used as first-line treatment in patients with different types of chronic wounds. METHOD: A systematic review of the literature was conducted. Databases (MEDLINE, Embase, Emcare, and Google Scholar) were searched up to 1 February 2024, without any language or time period limitations. Studies were eligible if the evaluated dressings had been used as a first-line treatment for chronic wounds, that is, as an integral part of the standard of care (SoC) at the patient's first presentation and/or in recent wounds. The main evaluation criteria included: wound healing rate; time to reach wound closure; change in patients' quality of life (QoL); and associated costs. The quality of evidence of the included studies was appraised using well-recognised risk-of-bias tools suitable for different study designs. A narrative synthesis describes the findings in three sections depending on the type of comparison. This report followed the principles of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RESULTS: A total of 17 studies published between 2017 and 2024 met the eligibility criteria. A comparative analysis between TLC-NOSF dressings and standard dressings, both of which were used as first-line treatment, was reported in nine studies. A comparative analysis between the use of TLC-NOSF dressings as first-line and second-line treatments was reported in eight studies, and five studies reported a systematic use of the TLC-NOSF dressing as first-line treatment without a control group. Overall, the included studies had a relatively low risk of bias for the respective types of evidence. Data of 10,191 patients of both sexes and different age groups with a total of 10,203 wounds (diabetic foot ulcers, leg ulcers, pressure injuries, and other types of chronic wounds) were included in the analysis: 7775 treated with the evaluated dressing and 2428 treated with a comparator dressing. The data suggested that using TLC-NOSF as a first-line treatment for chronic wounds consistently resulted in significantly higher healing rates, shorter healing times, and cost savings compared with standard dressings used under similar conditions. Real-life evidence confirmed the results obtained in clinical trials and economic models, within similar ranges, regardless of the settings involved or of the characteristics of the patients and wounds treated. The wound healing rates ranged around 70-80% by week 20/24 and time-to-heal was reported on average around seven weeks, with slightly longer times reported in wounds with a more severe prognosis. Furthermore, the dressings were shown to improve patient QoL, and were well tolerated and accepted, supporting a wider adoption approach. CONCLUSION: The results of this review are aligned with the current guidelines recommending the use of TLC-NOSF dressings in the treatment of patients with chronic wounds. They support its wider implementation as a first-line treatment and as an integral part of SoC for these wounds in the daily practice of all centres involved in their management.

Randomized Double-blind Cost-effectiveness Comparison of Two 10% Urea Creams in Patients with Diabetic Foot Syndrome.

OBJECTIVE: To evaluate the cost-effectiveness of two 10% urea creams in patients with diabetic foot syndrome. METHODS: This was a prospective, longitudinal, single-center, randomized, double-blind, prospective clinical trial that evaluated the skin quality of 20 feet belonging to 10 patients with diabetic foot syndrome after the application of two 10% urea creams purchased from pharmacies and supermarkets. RESULTS: At follow-up, 19 (95%) of the participants' feet showed improved skin quality, irrespective of the cream applied. On visual inspection, participants had a decreased presence of xerosis, hyperkeratosis, and preulcerative signs such as subkeratotic bruising and areas of redness on the dorsum of the toes. At the 3-month follow-up, nine (90%) of the participants stated that they had continued to apply the cream as a method of self-management to prevent complications. CONCLUSIONS: Creams containing 10% urea purchased in supermarkets improve foot skin quality in patients with diabetic foot syndrome, regardless of their cost. Based on these findings, the authors recommend creams containing 10% urea as a self-management tool for patients with diabetic foot syndrome.

Health-related quality of life among Spanish patients with diabetic foot ulcer according to Diabetic Foot Ulcer Scale - Short Form.

AIM: The aim of this study was to investigate the health-related quality of life of Spanish outpatients with diabetic foot ulcer using the Diabetic Foot Scale-Short Form (DFS-SF). MATERIALS AND METHODS: This cross-sectional observational study included 141 outpatients with diabetic foot ulcers (DFU). The DFS-SF was applied in personal interviews conducted by a trained investigator to assess health-related quality of life (HRQoL). RESULTS: The domain related to "worried about ulcers" had the lowest in score [50 (27.5-65.0)], and the highest score was in the physical health domain [76 (60.0-88.0)]. There was a statistically significant difference in the ulcer type and the physical health subscale, finding the lowest values in the physical health subscale in patients with ischaemic diabetic foot ulcers [58 (39.0-70.0), p = 0.007]. In the multivariable analysis the domains Leisure (OR 0.98, 95% CI 0.97-0.99) and worried about ulcers/feet (OR 0.98, 95% CI 0.96-0.99) were identified as significant independent domains in patients with the experience of a previous minor amputation. A significant negative correlation was observed between the SINBAD DFU score and leisure (r = -0.181, p = 0.032), physical health (r = -0.202, p = 0.016), dependence/daily life (r = -0.232, p = 0.006), and the "bothered by ulcer care" (r = -0.239, p = 0.004) domains of the DFS-SF. The ulcer duration had a significant negative correlation with all the domains of DFS-SF. CONCLUSION: The DFS-SF survey is a specific instrument that could be implemented in diabetic foot units as part of the management of patients with DFU to evaluate HRQoL. The domain of "worried about ulcers" had the lowest score in our population suggesting that clinicians should try to work on the emotional state of patients with DFU. The mean duration of DFU was the most influential factor related to worse scores followed by previous amputations. The SINBAD score had significant negative correlations suggesting that HRQoL may be related to the severity of DFU in this study population.

Role of bacterial multidrug efflux pumps during infection.

Multidrug efflux pumps are protein complexes located in the cell envelope that enable bacteria to expel, not only antibiotics, but also a wide array of molecules relevant for infection. Hence, they are important players in microbial pathogenesis. On the one hand, efflux pumps can extrude exogenous compounds, including host-produced antimicrobial molecules. Through this extrusion, pathogens can resist antimicrobial agents and evade host defenses. On the other hand, efflux pumps also have a role in the extrusion of endogenous compounds, such as bacterial intercommunication signaling molecules, virulence factors or metabolites. Therefore, efflux pumps are involved in the modulation of bacterial behavior and virulence, as well as in the maintenance of the bacterial homeostasis under different stresses found within the host. This review delves into the multifaceted roles that efflux pumps have, shedding light on their impact on bacterial virulence and their contribution to bacterial infection. These observations suggest that strategies targeting bacterial efflux pumps could both reinvigorate the efficacy of existing antibiotics and modulate the bacterial pathogenicity to the host. Thus, a comprehensive understanding of bacterial efflux pumps can be pivotal for the development of new effective strategies for the management of infectious diseases.

New experimental model to evaluate the effect of negative pressure wound therapy and viscosity exudates in foam dressings using confocal microscopy.

Negative pressure wound therapy is currently one of the most popular treatment approaches that provide a series of benefits to facilitate healing, including increased local blood perfusion with reduced localized oedema and control of wound exudate. The porous foam dressing is a critical element in the application of this therapy and its choice is based on its ability to manage exudate. Industry standards often employ aqueous solutions devoid of proteins to assess dressing performance. However, such standardized tests fail to capture the intricate dynamics of real wounds, oversimplifying the evaluation process. This study aims to evaluate the technical characteristics of two different commercial polyurethane foam dressings during negative pressure wound therapy. We introduce an innovative experimental model designed to evaluate the effects of this therapy on foam dressings in the presence of viscous exudates. Our findings reveal a proportional increase in dressing fibre occupancy as pressure intensifies, leading to a reduction in dressing pore size. The tests underscore the pressure system's diminished efficacy in fluid extraction with increasing fluid viscosity. Our discussion points to the need of establishing standardized guidelines for foam dressing selection based on pore size and the necessity of incorporating real biological exudates into industrial standards.

Does the use of DACC-coated dressings improve clinical outcomes for hard to heal wounds: A systematic review.

Reports of overuse and antimicrobial resistance have fuelled some clinicians to adopt alternative wound dressings termed to be non-medicated or non-antimicrobials, which still claim antimicrobial or antibacterial activity. In this PROSPERO-registered systematic review, we evaluated the in vivo clinical evidence for the effectiveness of DACC-coated dressings in chronic, hard to heal wound-related outcomes. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) Framework was adopted as the template in constructing this systematic review. The PICO format (Population [or patients], Intervention, Comparison [control], Outcome/s) was used to identify key clinical questions in determining patient outcomes under two domains (infection control and wound healing). A systematic search was performed in PubMed, OVID, Cochrane Library, clinical trial registries and data sources from independent committees. Abstracts of all studies were screened independently by two reviewers, with six further reviewers independently assessing records proceeding to full review. The authors rated the quality of evidence for each of the outcomes critical to decision making. After excluding duplicates, 748 records were screened from the databases, and 13 records were sought for full review. After full review, we excluded a further three records, leaving ten records for data extraction. Three records were narrative reviews, three systematic reviews, two prospective non-comparative before/after studies, one prospective head-to-head comparator cohort study and one retrospective head-to-head comparator cohort study. No RCTs or case versus control studies were identified. The overall quality of clinical evidence for the use of DACC-coated dressing to improve wound infection and wound healing outcomes was assessed as very low. There is an urgent unmet need to perform appropriately designed RCTs or case-control studies. The extracted data provide no clarity and have limited to no evidence to support that using a DACC-coated dressing improves wound infection or wound healing outcomes. Further, there is no evidence to suggest this therapy is either superior to standard of wound care or equivocal to topical antimicrobial agents in the management of infected hard to heal wounds.

Recurrence rates after healing in patients with neuroischemic diabetic foot ulcers healed with and without sucrose octasulfate-impregnated dressings: A 1-year comparative prospective study.

To compare recurrence rates after a 1-year follow-up period of healed neuroischemic diabetic foot ulcers after treatment with or without sucrose octasulfate impregnated dressing. A 1-year prospective study with two arms was conducted between April 2021 and April 2023 on 92 patients with healed neuroischemic diabetic foot ulcers. Patients were divided into two groups; the treatment group, that includes patients healed with a sucrose octasulfate-impregnated dressing, and the control group, which includes patients treated with other local treatments different from sucrose octasulfate-impregnated dressings. After healing, patients were prospectively followed up during 1-year and assessed monthly in the specialised outpatient clinics. The main outcome of the study was ulcer recurrence after wound healing within 1 year follow-up. Secondary outcomes were minor or major amputation and all causes of death. Fifty patients in the treatment group and 42 patients in the control group were included. Fourteen (28%) patients suffered from a reulceration event in the treatment group compared to 28 (66.7%) in the control group, p < 0.001. Time to recurrence in the treatment group was 10 (16.26-2.75) and 11.50 (30.75-5.25) weeks in the control group, p = 0.464. There were no observed differences in the minor amputation rates between the two groups: 15.2% (n = 7) in the treatment group and 7.1% (n = 3) in the control group (p = 0.362). Major amputations and death outcomes were exclusively observed in the treatment group. Specifically, four major amputations (8.7%) in the treatment group were complications arising from recurring events complicated by infection during the SARS-CoV-2 period. Seven patients died due to complications not related with local therapy. The relative risk of recurrence was 20.18 times higher in the control group compared with those treated with octasulfate dressing (p < 0.001). Treatment with sucrose octasulfate-impregnated dressings can decrease recurrence rates of neuroischaemic diabetic foot ulcers more effectively than neutral dressings. Besides, it may enhance the foot's clinical properties in patients with poor microcirculation, which could aid in preventing future recurrences.

Fluid handling by foam wound dressings: From engineering theory to advanced laboratory performance evaluations.

This article describes the contemporary bioengineering theory and practice of evaluating the fluid handling performance of foam-based dressings, with focus on the important and clinically relevant engineering structure-function relationships and on advanced laboratory testing methods for pre-clinical quantitative assessments of this common type of wound dressings. The effects of key wound dressing material-related and treatment-related physical factors on the absorbency and overall fluid handling of foam-based dressings are thoroughly and quantitively analysed. Discussions include exudate viscosity and temperature, action of mechanical forces and the dressing microstructure and associated interactions. Based on this comprehensive review, we propose a newly developed testing method, experimental metrics and clinical benchmarks that are clinically relevant and can set the standard for robust fluid handling performance evaluations. The purpose of this evaluative framework is to translate the physical characteristics and performance determinants of a foam dressing into achievable best clinical outcomes. These guiding principles are key to distinguishing desirable properties of a dressing that contribute to optimal performance in clinical settings.

Rapid Decline of Ceftazidime Resistance in Antibiotic-Free and Sublethal Environments Is Contingent on Genetic Background.

Trade-offs of antibiotic resistance evolution, such as fitness cost and collateral sensitivity (CS), could be exploited to drive evolution toward antibiotic susceptibility. Decline of resistance may occur when resistance to other drug leads to CS to the first one and when compensatory mutations, or genetic reversion of the original ones, reduce fitness cost. Here we describe the impact of antibiotic-free and sublethal environments on declining ceftazidime resistance in different Pseudomonas aeruginosa resistant mutants. We determined that decline of ceftazidime resistance occurs within 450 generations, which is caused by newly acquired mutations and not by reversion of the original ones, and that the original CS of these mutants is preserved. In addition, we observed that the frequency and degree of this decline is contingent on genetic background. Our results are relevant to implement evolution-based therapeutic approaches, as well as to redefine global policies of antibiotic use, such as drug cycling.