background: based on classical two-cell, two-gonadotropin theory, in the follicle, follicle-stimulating hormone (fsh) and luteinizing hormone (lh) put on their main effects on the granulosa and theca cells. lh is essential for androgens production. androgens are used for estradiol production by granulosa cells. profound suppression of lh concentrations in some normogonadotropic patients can cau...

Mechanical cues are employed to promote stem cell differentiation and functional tissue formation in tissue engineering and regenerative medicine. We have developed a Magnetic Force Bioreactor (MFB) that delivers highly targeted local forces to cells at a pico-newton level, utilizing magnetic micro- and nano-particles to target cell surface receptors. In this study, we investigated the effects ...

The present experiment examined the effect of aspirin on the escape/avoidance behavioral response to a mechanical stimulus (476 mN von Frey mono®lament) in the place escape avoidance paradigm (PEAP) following subcutaneous administration of carrageenan (CARR). Forty-one male Sprague±Dawley rats received subcutaneous injection of CARR or saline in the left hindpaw and 3 1/2 h later were administe...

OBJECTIVE Magnetoencephalography (MEG) recordings were performed to investigate the cortical activation following tactile-on and tactile-off stimulation. METHODS We used a 306-ch whole-head MEG system and a tactile stimulator driven by a piezoelectric actuator. Tactile stimuli were applied to the tip of right index finger. The interstimulus interval was set at 2000 ms, which included a consta...

Although the neurokinin-1 (NK-1)/substance P (SP) receptor is expressed by neurons throughout the spinal dorsal horn, noxious chemical stimulation in the normal rat only induces internalization of the receptor in cell bodies and dendrites of lamina I. Here we compared the effects of mechanical and thermal stimulation in normal rats and in rats with persistent hindpaw inflammation. Electron micr...

Repetitive activity at the non-myelinated ending of Pacinian corpuscles leaves the following after-effects: (1) With certain parameters of repetitive mechanical stimulation of the ending a depression in generator potential is produced. The effect is fully reversible and has low energy requirements. The effect is a transient decrease in responsiveness of the receptor membrane which is unrelated ...

BACKGROUND Mesenchymal stem cells (MSC) are multipotent cells which can differentiate along osteogenic, chondrogenic, and adipogenic lineages. The present study was designed to investigate the influence of mechanical force as a specific physiological stress on the differentiation of (MSC) to osteoblast-like cells. METHODS Human MSC were cultured in osteoinductive medium with or without cyclic...

The present study was performed to explore the effect of subcutaneous injection of carrageenan into the rat plantar region on hindpaw edema formation and the latency of hindpaw withdrawal to presumed nociceptive stimulation. Subcutaneous injection of carrageenan into the left hindpaw induced a significant increase in the volume of the left hindpaw, leaving the right side unaffected. In addition...

Tidball, James G. Mechanical signal transduction in skeletal muscle growth and adaptation. J Appl Physiol 98: 1900 –1908, 2005; doi:10.1152/japplphysiol. 01178.2004.—The adaptability of skeletal muscle to changes in the mechanical environment has been well characterized at the tissue and system levels, but the mechanisms through which mechanical signals are transduced to chemical signals that i...

The effects of mechanical stability and mechanical stimulation have been studied extensively in vivo using a variety of animal models and stimulators. Early results indicated that stimulation does not significantly contribute to fracture healing. Lately, however, more rigid external stimulators that withstand increased callus formation have identified a contribution of mechanical stimulation in...