Skin Acute Wound Healing: A Comprehensive Review.

Experimental work of the last two decades has revealed the general steps of the wound healing process. This complex network has been organized in three sequential and overlapping steps. The first step of the inflammatory phase is an immediate response to injury; primary sensory neurons sense injury and send danger signals to the brain, to stop bleeding and start inflammation. The following target of the inflammatory phase, led by the peripheral blood mononuclear cells, is to eliminate the pathogens and clean the wound. Once this is completed, the inflammatory phase is resolved and homeostasis is restored. The aim of the proliferative phase, the second phase, is to repair wound damage and begin tissue remodeling. Fibroplasia, reepithelialization, angiogenesis, and peripheral nerve repair are the central actions of this phase. Lastly, the objective of the final phase is to complete tissue remodeling and restore skin integrity. This review provides present day information regarding the status of the participant cells, extracellular matrix, cytokines, chemokines, and growth factors, as well as their interactions with the microenvironment during the wound healing process.

Efficacy and safety evaluation of systemic extremely low frequency magnetic fields used in the healing of diabetic foot ulcers--phase II data.

BACKGROUND AND AIMS: Cellular and animal models investigating extremely low frequency magnetic fields (ELF-MF) have reported promotion of leukocyte-endothelial interactions, angiogenesis, myofibroblast and keratinocyte proliferation, improvement of peripheral neuropathy and diabetic wound healing. In humans, it has also been reported that systemic exposure to ELF-MF stimulates peripheral blood mononuclear cells, promoting angiogenesis and healing of chronic leg ulcers. The aim of the study was to investigate the effect of exposing different blood volumes to specific ELF-MFs (120 Hz sinusoidal waves of 0.4-0.9 mT RMS) to induce healing of diabetic foot ulcers (DFUs). METHODS: Twenty six diabetic patients with non-responsive DFUs were divided into two exposure groups to receive treatment and record healing time. The forearm group, exposed to ELF-MF 2 h/day, twice weekly (3.6 l of blood/session); and the thorax group, exposed 25 min/day, 2 times/week (162.5 l of blood/session). Treatment period was 100 days or upon complete healing. Ulcer recurrences and adverse effects were investigated during short-term (<1 year) and long-term (3.4-7.8 years) follow-up. RESULTS: Mean healing time was 61.48 ± 33.08 days in the forearm group and 62.56 ± 29.33 days for the thorax group. No adverse effects or ulcer recurrences in the original ulcer site were reported during treatment, the short-term follow-up period or the long-term follow-up period in both groups. CONCLUSIONS: Healing time was independent of the amount of blood exposed to ELF-MF used in this trial. ELF-MFs are effective and safe and could be applied to non-healing DFUs in conjunction with other preventive interventions to reduce DFUs complications.

Increased vascular permeability in the circumventricular organs of adult rat brain due to stimulation by extremely low frequency magnetic fields.

It has been demonstrated that the exposure of biological systems to magnetic fields (MFs) can produce several beneficial effects: tissue recovery in chronic wounds, re-establishment of blood circulation after tissue ischemia or in necrotic tissues, improvement after epileptic episodes, angiogenesis, etc. In the current study, the effects of extremely low frequency (ELF) MF on the capillaries of some circumventricular organs (CVOs) are demonstrated; a vasodilator effect is reported as well as an increase in their permeability to non-liposoluble substances. For this study, 96 Wistar male rats (250 g body mass) were used and divided into three groups of 32 rats each: a control group (no treatment); a sham ELF-MF group; and an experimental group subjected to ELF-MF (120 Hz harmonic waves and 0.66 mT, root mean square) by the use of Helmholtz coils. All animals were administered colloidal carbon (CC) intravenously to study, through optical and transmission electron microscopy, the capillary permeability in CVOs and the blood-brain barrier (BBB) in brain areas. An increase in capillary permeability to CC was detected in the ELF-MF-exposed group as well as a significant increase in vascular area (capillary vasodilation); none of these effects were observed in individuals of the control and sham ELF-MF groups. It is important to investigate the mechanisms involved in the phenomena reported here in order to explain the effects of ELF-MF on brain vasculature.

Healing of chronic arterial and venous leg ulcers through systemic effects of electromagnetic fields [corrected].

BACKGROUND: Mitogen-activated autologous peripheral blood mononuclear cells applied locally on the ulcer surface promote healing of chronic arterial and venous leg ulcers. In vitro, extremely low frequency electromagnetic fields (ELF) interact with peripheral blood mononuclear cells (PBMC) via Ca++ channels, activating signal transduction cascades, promoting cytokine synthesis, and changing cell proliferation patterns. METHODS: ELF frequencies were configured to interact in vitro with the proliferation patterns of PBMC obtained from normal human volunteers. These ELF were then applied peripherally as the sole treatment to 26 patients with 42 chronic leg ulcers of predominantly arterial or venous etiology unresponsive to previous medical and/or surgical treatments in a phase I before-after design. RESULTS: At admission, age of ulcers had a skewed distribution with a median of 639 days. Wound healing or deleterious effects began in all patients during the first 2 weeks after ELF exposure, permitting their previously unresponsive ulcers to function as internal controls. After ELF exposure, 69% of all lesions were cured or healed >50% in a period <4 months. Defective wound healing was observed in lesions associated with important arterial occlusion, uncontrolled arterial hypertension, severe lipodermatosclerosis, non-pitting edema, and obesity (body mass index >30). Lesions worsened in patients with autoimmune diseases. CONCLUSIONS: Systemic effects are hypothetically explained by ELF activation of PBMC and their subsequent transportation to the ulcer site via humoral route. This therapy is effective in selected patients with chronic arterial and venous leg ulcers.