Search

Chronic wounds result from the body's inability to heal, causing pain, pathogen entry, limited treatment options, and societal burden. Diabetic foot ulcers are particularly challenging, often leading to severe complications like leg amputation. A clinical study tested AMNIODERM+ ® , a new device with a lyophilized human amniotic membrane (HAM), on chronic diabetic foot ulcers. Participants had diabetic neuropathic or neuroischemic leg wounds (2-16 cm 2 ) unhealed by 20% after six weeks of standard care. This study showed significant wound healing improvements with AMNIODERM+ ® . The median wound size reduction after 12 weeks was 95.5%, far exceeding the null hypothesis of 20% change. Additionally, 65% of patients achieved complete ulceration healing, surpassing the 50% efficacy requirement. The median time to full closure was 11.4 weeks, with the proportion of completely healed patients rising progressively, reaching 55% by week 11. These findings, from the clinical trial "Freeze-dried amniotic membrane in the treatment of nonhealing wounds", suggest AMNIODERM+ ® as a promising future treatment for chronic diabetic foot ulcers. The published results were obtained as part of a clinical trial entitled "Freeze-dried amniotic membrane in the treatment of nonhealing wounds: a single-arm, retrospectively-perspective clinical trial", EUDAMED Nr. CIV-SK-22-10-041146.

Nanofibers are well known as a beneficial type of structure for tissue engineering. As a result of the high acquisition cost of the natural polymers and their environmentally problematic treatment (toxic dissolution agents), artificial polymers seem to be the better choice for medical use. In the present study, polycaprolactone nano-sized fibrous structures were prepared by the electrospinning method. The impact of material morphology (random or parallelly oriented fibers versus continuous layer) and the presence of a fraction of hydroxyapatite nanoparticles on cell proliferation was tested. In addition, the effect of improving the material wettability by a low temperature argon discharge plasma treatment was evaluated, too. We have shown that both hydroxyapatite particles as well as plasma surface treatment are beneficial for the cell proliferation. The significant impact of both influences was evident during the first 48 h of the test: the hydroxyapatite particles in polycaprolactone fibers accelerated the proliferation by 10% compared to the control, and the plasma-treated ones enhanced proliferation by 30%.

Electrospinning as a versatile technique producing nanofibers was employed to study the influence of the processing parameters and chemical and physical parameters of solutions on poly(vinylidene fluoride) (PVDF) fibers' morphology, crystallinity, phase composition and dielectric and piezoelectric characteristics. PVDF fibrous layers with nano- and micro-sized fiber diameters were prepared by a controlled and reliable electrospinning process. The fibers with diameters from 276 nm to 1392 nm were spun at a voltage of 25 kV-50 kV from the pure PVDF solutions or in the presence of a surfactant-Hexadecyltrimethylammonium bromide (CTAB). Although the presence of the CTAB decreased the fibers' diameter and increased the electroactive phase content, the piezoelectric performance of the PVDF material was evidently deteriorated. The maximum piezoelectric activity was achieved in the fibrous PVDF material without the use of the surfactant, when a piezoelectric charge of 33 pC N -1 was measured in the transversal direction on a mean fiber diameter of 649 nm. In this direction, the material showed a higher piezoelectric activity than in the longitudinal direction.

Background and Purpose: NMDA receptors are glutamatergic ionotropic receptors involved in excitatory neurotransmission, synaptic plasticity and excitotoxic cell death. Many allosteric modulators can influence the activity of these receptors positively or negatively, with behavioural consequences. 20-Oxo-5β-pregnan-3α-yl sulphate (pregnanolone sulphate; PA-6) is an endogenous neurosteroid that inhibits NMDA receptors and is neuroprotective. We tested the hypothesis that the interaction of PA-6 with the plasma membrane is critical for its inhibitory effect at NMDA receptors., Experimental Approach: Electrophysiological recordings and live microscopy were performed on heterologous HEK293 cells expressing GluN1/GluN2B receptors and cultured rat hippocampal neurons., Key Results: Our experiments showed that the kinetics of the steroid inhibition were slow and not typical of drug-receptor interaction in an aqueous solution. In addition, the recovery from steroid inhibition was accelerated by β- and γ-cyclodextrin. Values of IC(50) assessed for novel synthetic C3 analogues of PA-6 differed by more than 30-fold and were positively correlated with the lipophilicity of the PA-6 analogues. Finally, the onset of inhibition induced by C3 analogues of PA-6 ranged from use-dependent to use-independent. The onset and offset of cell staining by fluorescent analogues of PA-6 were slower than those of steroid-induced inhibition of current responses mediated by NMDA receptors., Conclusion and Implications: We conclude that steroid accumulation in the plasma membrane is the route by which it accesses a binding site on the NMDA receptor. Thus, our results provide a possible structural framework for pharmacologically targeting the transmembrane domains of the receptor., (© 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.)