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by control seeding (conventional method; seeding without a magnet). After a 14-day
cultivation period using osteogenic induction medium by Mag-seeding, the levels of two
representative osteogenic markers (alkaline phosphatase and osteocalcin) were found to
be significantly higher than those by control seeding. These results indicate that Magseeding of BMSCs into HA scaffolds is an effective approach to bone tissue engineering.
3.5.5 Treatments of Pain, Cancer, and Other Diseases
The clinical effects of SMFs and PEMFs on pain have been well reviewed (Markov
2007; Colbert et al. 2009). Khoromi et al. (2007) assessed the pain-relieving efficacy of
SMF (20 mT versus 5 mT) in a double-blind, randomized, two-phase crossover study
in patients with chronic lumbar radicular pain. The effect of 20-mT SMF relative to
5-mT SMF appeared to increase throughout the week period. The authors proposed that
larger, longer-duration, sham-controlled trials with 20-mT magnets should be considered in patients with chronic lumbar radicular pain.
Regarding the effects of PEMF on analgesia, Weintraub and Cole (2004) evaluated
a PEMF therapy (30 Hz, 2 mT, 1 h/day, five days a week, for nine days) in refractory
neuropathic pain in the soles of the feet. These pilot data demonstrated that directing
PEMFs to refractory neuropathic pain treatment can provide unexpected short-term
analgesic effects in more than 50% of individuals. The role of placebo is not known and
was not tested. The authors stated that the precise mechanism is unclear, but suggested
that severe and advanced cases are more magnetically sensitive.
The same research group further investigated in patients with carpal tunnel syndrome (CTS) (Weintraub and Cole 2008). The authors revealed that PEMF + SMF
exposure (20 Hz, 5 mT, 0.5 mV/cm, 4 h/day for 2–10 months) in refractory CTS provides
statistically significant short- and long-term pain reduction and mild improvement in
objective neuronal functions. They suggested that neuromodulation appears to influence nociceptive-C and large A-fiber functions, probably through ion/ligand binding.
Shupak et al. (2006) reported the effect of PEMF (<3 kHz, ≤400 μT, 30 minutes) on
pain and anxiety ratings in female rheumatoid arthritis and fibromyalgia patients with
a double-blind, randomized, placebo-controlled design. The results provide some initial
support for the use of PEMF exposure in reducing pain in chronic pain populations
and warrant continued investigation into the use of PEMF exposure for short-term pain
relief. Sutbeyaz et al. (2009) further suggested that PEMF therapy (64 Hz, 40 μT, 30 minutes per session, twice a day for 3 weeks) might improve function, pain, fatigue, and
global status in fibromyalgia patients.
Fernandez, Watson, and Rowbotham (2007) reported that PEMF exposure (1.25 Hz,
3-ms duration, 60 mT, for 30 minutes) had no effect on pain. Weintraub et al. (2009) also
confirmed that a PEMF (25 Hz, 31 mT) was noneffective in reducing neuropathic pain.
However, they proposed future studies with higher dosimetry (300–500 mT), longer
duration of exposure, and larger biopsy cohort.
More recent preclinical studies examining the inhibition of angiogenesis by exposure
to magnetic fields have turned to the use of magnetic fields in the treatment of cancer
(tumor angiogenesis; see also Sections 3.3.1.5 and 3.3.2.1). Brix et al. (2008) evaluated SMF