Analgesic Activity of Cinnabarinic Acid in Models of Inflammatory and Neuropathic Pain

Cinnabarinic acid (CA) is a trace kynurenine metabolite, which activates both type-4 metabotropic glutamate (mGlu4) and arylic hydrocarbon (Ah) receptors. We examined the action of CA in models of inflammatory and neuropathic pain moving from the evidence that mGlu4 receptors are involved in the regulation of pain thresholds. Systemic administration of low doses of CA (0.125 and 0.25 mg/kg, i.p.) reduced nocifensive behaviour in the second phase of the formalin test. CA-induced analgesia was abrogated in mGlu4 receptor knockout mice, but was unaffected by treatment with the Ah receptor antagonist, CH223191 (1 mg/Kg, s.c.). Acute injection of low doses of CA (0.25 mg/kg, i.p.) also caused analgesia in mice subjected to Chronic Constriction Injury (CCI) of the sciatic nerve. Electrophysiological recording showed no effect of CA on spinal cord nociceptive neurons and a trend to a lowering effect on the frequency and duration of excitation of the rostral ventromedial medulla (RVM) ON cells in CCI mice. However, local application of CH223191 or the group-III mGlu receptor antagonist, MSOP disclosed a substantial lowering and enhancing effect of CA on both populations of neurons, respectively. When repeatedly administered to CCI mice, CA retained the analgesic activity only when combined with CH223191. Repeated administration of CA plus CH223191 restrained the activity of both spinal nociceptive neurons and RVM ON cells, in full agreement with the analgesic activity. These findings suggest that CA is involved in the regulation of pain transmission, and its overall effect depends on the recruitment of mGlu4 and Ah receptors.

Ambulant vacuum-assisted closure of skin-graft dressing in the lower limbs using a portable mini-VAC device

A skin graft may fail to adhere to the recipient site because of fluid collecting between the graft and the area being treated. We have devised a simple procedure, consisting of a vacuum-sealed dressing, to fix skin grafts on the lower limbs. A fully portable, battery-operated aspirator continuously draws secretions through a vacuum-sealed dressing, preventing accumulation of fluid underneath the graft. Patients are not confined to bed, thus reducing nursing time. The procedure was applied successfully in seven out of nine patients treated for ulcers of the lower limbs.

Multiple CT imaging in pressure sores

In patients affected by pressure sores, bones can be reached easily by the infection. This suggested a new way for a more precise diagnostic evaluation, looking at the most recent technological knowledge, which can offer a better evaluation of single lesions for a better planning of surgical operations. The possibility of performing multiple imaging under a CT guide, as well as a simple technique for contrast permanence within the sore, led the authors to demonstrate the validity of modern CT scanning as a main diagnostic method.

The effect of concomitant chondral injuries accompanying operatively reduced malleolar fractures

The best clinical results in the treatment of malleolar fractures occur when an anatomic reduction is obtained and maintained until the fractures are healed. Ankle pain and/or tibio-talar arthrosis has been reported despite anatomic surgical reduction and stable fixation of the malleoli. This may be due to unrecognized injuries to the cartilaginous surfaces of the tibio-talar joint. Between 1984 and 1987, 63 patients with isolated closed malleolar fractures underwent open reduction and internal fixation using standard AO techniques. Each patient had inspection of the entire talar dome during surgery. There were seven type A, 37 type B, and 19 type C fractures. Thirty-one patients (49%) had injuries to the talar dome cartilage, ranging from mild scuffing to free osteochondral fragments. Twenty-five patients were available for a follow-up evaluation at an average of 25 months after surgery. Thirteen patients had some complaints of pain, eight of whom had talar dome chondral injuries. The overall results, including functional status and ankle range of motion, were significantly poorer in patients with talar dome chondral injuries (p less than or equal to 0.03 and p less than or equal to 0.042, respectively).

The use of a modified tonometer in burn scar therapy

We report on the use of a modified Schiotz tonometer to evaluate the effects of therapies on burn scars. It is now possible to quantify the course of cicatrization with tonometry. Because tonometry affords a precise evaluation of burn scar diagnosis and prognosis, it is possible to avoid arbitrary clinical evaluation of the burn scarring process.