Reflections on the effects of nitric oxide produced by a new dressing in the local management of diabetic foot ulcers

First Report on the Phenotypic and Genotypic Susceptibility Profiles to Silver Nitrate in Bacterial Strains Isolated from Infected Leg Ulcers in Romanian Patients

Silver-ion-based antiseptics are widely used in treating chronic leg ulcers and, given the emergence of resistance to such compounds, the investigation of silver susceptibility and resistance profiles of pathogenic strains isolated from this type of wound is a topic of great interest. Therefore, in this study, 125 bacterial strains isolated from 103 patients with venous ulcers were investigated to elucidate their susceptibility to silver-nitrate solutions in planktonic and biofilm growth states, and the associated genetic determinants. The isolated strains, both in the planktonic and biofilm growth phases, showed high sensitivity to the standard concentration of 1/6000 silver-nitrate solution. It was noticed that even at concentrations lower than the clinical one (the first 2–3 binary dilutions in the case of planktonic cultures and the first 6–7 binary dilutions in the case of biofilms), the antiseptic solution proved to maintain its antibacterial activity. The phenotypic results were correlated with the genetic analysis, highlighting the presence of silver-resistance genes (sil operon) in only a few of the tested Staphylococcus sp. (especially in S. aureus) strains, Escherichia coli and Pseudomonas aeruginosa strains. These results demonstrate that despite its large use, this antiseptic remains a viable treatment alternative for the management of chronic leg wounds.

Effect and Mechanism of the Bruton Tyrosine Kinase (Btk) Inhibitor Ibrutinib on Rat Model of Diabetic Foot Ulcers

BACKGROUND Diabetes causes damage to the soft tissue and bone structure of the foot, referred to as "diabetic foot". Ibrutinib is a Bruton tyrosine kinase (Btk) inhibitor, and the role and mechanism of ibrutinib on the diabetic foot have not been elucidated. MATERIAL AND METHODS Male Wister rats were randomly divided into 3 groups: control group, model group, and ibrutinib group. After 14 days, the ulcer wound size of each group was measured, and the ulcer healing rate was calculated. The level of inflammatory factors interleukin (IL)-1ß, tumor necrosis factor (TNF)-alpha, and IL-6 was detected by enzyme-linked immunosorbent assay (ELISA). Real-time polymerase chain reaction (PCR) was used to analyze the changes of Toll-like receptor 2 (TLR2) and TLR4. The expression of vascular endothelial growth factor (VEGF) and the RAGE (receptor for advanced glycation end product/NF-kappaB (nuclear factor-kappa B) pathway was detected by western blot. RESULTS Blood glucose, blood lipids, serum creatinine, and urea nitrogen (BUN) levels were increased in the model group, together with increased levels of IL-1ß, TNF-alpha, IL-6, as well as TLR2 and TLR4 expression, and there were significant differences compared with the control group (P<0.05). Meanwhile, the model group showed decreased VEGF expression and increased expression of RAGE and NF-kappaB. However, ibrutinib reduced blood sugar, blood lipids, creatinine, and urea nitrogen levels, inhibited the secretion of inflammatory factors, promoted ulcer healing, improved ulcer healing rate, decreased the expression of TLR2, TLR4, RAGE, and NF-kappaB, and increased VEGF expression; there were significant differences in the ibrutinib group compared with the model group (P<0.05). CONCLUSIONS The Btk inhibitor ibrutinib can upregulate VEGF expression, inhibit the expression of TLRs, inhibit the secretion of inflammatory factors, and promote the healing of diabetic foot ulcer possibly by regulating the RAGE/NF-kappaB pathway.