Osa Emohare | PubMed Health

PubMed2004

Laser-induced thermal stress and the heat shock response in neural cells.

BACKGROUND: The Ho: YAG laser is used extensively in orthopedic surgery. It offers a minimally invasive method of ablating tissue with precision. Previous studies have explored the effects of laser use on temperature during experimental foraminoplasty. To date, there has been limited work on the effects of thermal stress on cells in this context. Material and methods Cells were exposed either to heated medium or the Ho: YAG laser in the high-power mode. Heated medium was used as a stressor by (I) exposing groups of cells to a constant temperature of 45 degrees C for varying lengths of time: 5, 10, 15 and 20 min, and (II) exposing cells for a fixed length of time (5 min) to varying temperatures: 45 degrees C, 55 degrees C, 65 degrees C with a control treated at 37 degrees C. A third group was subjected to direct laser treatment. The effects of the treatments were assessed using trypan blue staining as a measure of viability and immunocytochemistry was used to measure changes in heat shock protein (HSP) expression. RESULTS: There was a negative correlation between cell viability and HSP expression, and between cell viability and the severity of the treatment. INTERPRETATION: Our findings suggest a possible role for the Ho: YAG laser in spinal foraminoplasty based on the high level of cell viability in the treatment regimen that most closely mirrored the clinical application of the laser.

Animals↗

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Vacuum-assisted closure use in calciphylaxis.

Calciphylaxis-induced chronic wounds are difficult to heal. The value of vacuum-assisted closure (VAC) was assessed in two patients with calciphylaxis. Two middle-aged females with type 2 diabetes were transferred to the burn unit with a clinical diagnosis of necrotizing fasciitis, although the pathologic diagnosis was calciphylaxis. With extensive debridement, antibiotics, and meticulous wound care, one patient had progressive necrosis of her skin from 18 to 48% TBSA, whereas the other progressed from 5 to 10% TBSA only. The patient with the smaller chronic wound healed well and left the hospital at 72 days after admission. Although there was some success with the use of VAC, the patient with the extensive progressive wounds developed a fungal wound infection that did not respond to treatment; she died 78 days after initiation of burn center treatment. Some disadvantages to the usefulness would be extensive contiguous wounds and the lack of an intact skin surface. The VAC system was of value in healing wounds resulting from calciphylaxis.

Calciphylaxis↗