Up-regulation of expression of selected genes in human bone cells with specific capacitively coupled electric fields.

The objective of the described experiments was to determine the electrical parameters that lead to optimal expression of a number of bone-related genes in cultured human bone cells exposed to a capacitively coupled electric field. Human calvarial osteoblasts were grown in modified plastic Cooper dishes in which the cells could be exposed to various capacitively coupled electric fields. The optimal duration of stimulation and optimal duration of response to the electrical field, and the optimal amplitude, frequency and duty cycle were all determined for each of the genes analyzed.

The effect of electrical fields on gene and protein expression in human osteoarthritic cartilage explants.

Background: The destruction of cartilage in patients with osteoarthritis is a consequence of an imbalance between matrix synthesis and degradation. The purpose of the present study was to determine the effects of electrical stimulation on these processes in full-thickness osteoarthritic adult human articular cartilage explants.

Methods: Full-thickness articular cartilage explants from osteoarthritic adult human knee joints were cultured in the absence or presence of interleukin-1beta (IL-1beta) and in the absence or presence of a specifically defined capacitively coupled electrical signal for seven or fourteen days.

The required research rotation in residency: the University of Pennsylvania experience, 1978-1993.

The University of Pennsylvania orthopaedic surgery residency program under the direction of Dr. Carl T. Brighton was uniquely structured to require a year of research as part of a 5-year program.

Up-regulation of bone morphogenetic proteins in cultured murine bone cells with use of specific electric fields.

Background: Capacitively coupled electric stimulation has been successfully used in the treatment of bone nonunions and to effect spinal fusions. However, the pathway of biologic events whereby this is accomplished has not been fully elucidated. To determine whether bone morphogenetic proteins (BMPs) could be involved, the effect of electrical stimulation on BMP gene expression was investigated.

Up-regulation of matrix in bovine articular cartilage explants by electric fields.

Electric stimulation has long been used as a tool to promote connective tissue healing, but the mechanism(s) by which this is accomplished are not yet known. We have previously determined, using mass cultures of fetal bovine articular chondrocytes, a specific set of capacitively coupled electrical stimulation parameters (e.g.

Up-regulation of chondrocyte matrix genes and products by electric fields.

This study tested the hypothesis that selective and specific capacitively coupled electrical signals could stimulate gene expression and matrix production in bovine articular chondrocytes. Starting with a capacitively coupled electric signal that previously was shown to be effective in stimulating proliferation in bovine articular cartilage chondrocytes, dose responses were done sequentially for duration, response time, amplitude, duty cycle, and frequency. Results showed that a 0.

Use of physical forces in bone healing.

During the past two decades, a number of physical modalities have been approved for the management of nonunions and delayed unions. Implantable direct current stimulation is effective in managing established nonunions of the extremities and as an adjuvant in achieving spinal fusion. Pulsed electromagnetic fields and capacitive coupling induce fields through the soft tissue, resulting in low-magnitude voltage and currents at the fracture site.