Conectar
From previous studies, we have shown that viable colony forming units of bacteria and bacterial biofilms are reduced after sequential treatment with a surfactant-based dressing. Here, we sought to test the impact on visible bacterial pigments and the ultrastructural impact following the sequential treatment of the same surfactant-based dressing. Mature Pseudomonas aeruginosa biofilms were grown on ex vivo porcine skin explants, and an imaging-based analysis was used to compare the skin with and without a concentrated surfactant. In explants naturally tinted by bacterial chromophores, wiping alone had no effect, while the use of a surfactant-based dressing reduced coloration. Similarly, daily wiping led to increased immunohistochemical staining for P. aeruginosa antigens, but not in the surfactant group. Confocal immunofluorescent imaging revealed limited bacterial penetration and coating of the dermis and loose pieces of sloughing material. Ultrastructural analysis confirmed that the biofilms were masking the extracellular matrix (ECM), but the surfactant could remove them, re-exposing the ECM. The masking of the ECM may provide another non-inflammatory explanation for delayed healing, as the ECM is no longer accessible for wound cell locomotion. The use of a poloxamer-based surfactant appears to be an effective way to remove bacterial chromophores and the biofilm coating the ECM fibres.
The increased peripheral arterial disease (PAD) incidence associated with aging and increased incidence of cardiovascular conditions underscores the significance of assessing lower limb perfusion. This study aims to report on the correlation and utility of two novel non-invasive instruments: transcutaneous oxygen pressure (TcPO2) and forward-looking infrared (FLIR) thermography. A total of 68 patients diagnosed with diabetic foot ulcer and PAD who underwent vascular studies at a single institution between March 2022 and March 2023 were included. Cases with revascularization indications were treated by a cardiologist. Following the procedure, ambient TcPO2 and FLIR thermography were recorded on postoperative days 1, 7, 14, 21 and 28. In impaired limbs, TcPO2 was 12.3 ± 2 mmHg and FLIR thermography was 28.7 ± 0.9°C. TcPO2 (p = 0.002), FLIR thermography (p = 0.015) and ankle–brachial index (p = 0.047) values significantly reduced with greater vascular obstruction severity. Revascularization (n = 39) significantly improved TcPO2 (12.5 ± 1.7 to 19.1 ± 2.2 mmHg, p = 0.011) and FLIR (28.8 ± 1.8 to 32.6 ± 1.6°C; p = 0.018), especially in severe impaired angiosomes. TcPO2 significantly increased immediately post-procedure, then gradually, whereas the FLIR thermography values plateaued from day 1 to 28 post-procedure. In conclusion, FLIR thermography is a viable non-invasive tool for evaluating lower limb perfusion based on angiosomes, comparable with TcPO2.
Diabetic foot ulcer and diabetic kidney disease are diabetes-related chronic vascular complications that strongly correlate with high morbidity and mortality. Although metformin potentially confers a wound-healing advantage, no well-established clinical evidence supports the benefit of metformin for diabetic foot ulcer. Thus, this study investigated the effect of metformin on diabetic foot ulcer from a large diabetic kidney disease cohort for the first time. This retrospective cohort study enrolled 10 832 patients who visited the nephrology department more than twice at two South Korean tertiary-referral centers between 2001 and 2016. The primary outcome was diabetic foot ulcer events; secondary outcomes included hospitalization, amputation, a composite of amputation or vascular intervention, and Wagner Grade ≥ 3. Multivariate Cox analysis and propensity score matching (PSM) were used to balance baseline intergroup differences between metformin users and non-users. In total, 4748 patients were metformin users, and 6084 patients were metformin non-users. Over a follow-up period of 117.5 ± 66.9 months, the diabetic foot ulcer incidence was 5.2%. After PSM, metformin users showed a lower incidence of diabetic foot ulcer events than metformin non-users (adjusted hazard ratio 0.41; p < 0.001). In a sensitivity analysis of 563 patients with diabetic foot ulcer, metformin usage was associated with lower severity in all four secondary outcomes: hospitalization (adjusted hazard ratio 0.33; p < 0.001); amputation (adjusted hazard ratio 0.44; p = 0.001); composite of amputation or vascular intervention (adjusted hazard ratio 0.47; p < 0.001); and Wagner Grade ≥ 3 (adjusted hazard ratio 0.39; p < 0.001). In conclusion, metformin therapy in patients with diabetic kidney disease can lower diabetic foot ulcer incidence and progression.
FreshRSS 