169
Static, Low-Frequency, and Pulsed Magnetic Fields
hemisphere. A total of 87 patients were further analyzed using useful data from both
the combined method and the Wada test. The authors observed a 100% match of the
combined method results with the results of the Wada test, including two patients who
showed expressive and receptive language areas dissociated into bilateral hemispheres.
The results demonstrated that this noninvasive and repeatable method is not only highly
reliable in determining language dominance, but it can also locate the expressive and
receptive language areas separately. The authors suggested that the method is a potent
alternative to the invasive procedures of the Wada test and is useful in treating patients
with brain lesions.
3.5.4 Magnetic Orientation for Tissue Engineering
The effects of magnetic fields, in particular, SMFs, on magnetic orientation for tissue
engineering have been reported (see the review by Ueno, Sekino, and Ogiue-Ikeda
2006). That is, the magnetic control of living cells using magnetic force may translate
into potentially viable tissue and promising medical engineering applications including
nerve regeneration. In this case, recognition of the role of diamagnetic, paramagnetic,
and ferromagnetic materials in vitro and in vivo may help in unraveling the underlying
mechanisms.
Umeno and Ueno (2003) examined the effect of strong SMFs on adherent cells. The
previous study by Iwasaka and Ueno (2003) showed that smooth muscle cells cultured
in 8- or 14-T superconducting magnets for three days exhibited orientational order parallel to the magnetic field direction. To discuss the process and the mechanism of this
orientation, the authors investigated the orientational characteristics of the cell culture
with quantitative measurements: an orientational order parameter and the FT analysis.
The orientational order parameter indicated the degree of orientation. The value of the
parameter was estimated with the FT of microscopic images. The cells cultured under
stronger SMFs exhibited stronger ordering, when they were cultured under a strong
magnetic gradient force of 400 T 2 /m. By contrast, they showed weaker ordering in the
control. The ordering was enhanced under uniform, strong magnetic fields, whereas it
was not affected or was suppressed by strong gradient forces. The authors suggested that
the cells organize themselves to minimize their diamagnetic torsion stresses, which can
be induced in the uniform magnetic fields by the membrane’s diamagnetic anisotropy.
In contrast to the estimation of torque force induced by a uniform SMF, the intense
inhomogeneous SMF acting on diamagnetic materials can generate a strong magnetic
force. Qian et al. (2009) have developed a superconducting magnet platform with largegradient high magnetic field (LG-HMF), which can produce three magnetic force fields
of −1360, 0, and 1312 T 2 /m and three corresponding apparent gravity levels of 0, 1, and
2 g for diamagnetic materials. The authors investigated the effects of different magnetic
force fields on osteoblast-like cell (MG-63 and MC3T3-E1) viability, microtubule actin
cross-linking factor 1 (MACF1) expression, and MACF1’s association with cytoskeleton.
Results showed that cell viability increased to different degrees after 24 hours of exposure to 0 or 1 g conditions, whereas it decreased by about 30% under 2 g conditions
compared with the control conditions. An increase in MACF1 expression at the RNA
or protein level was observed in osteoblast-like cells under the LG-HMF of −1360 T 2 /m
Static, Low-Frequency, and Pulsed Magnetic Fields
hemisphere. A total of 87 patients were further analyzed using useful data from both
the combined method and the Wada test. The authors observed a 100% match of the
combined method results with the results of the Wada test, including two patients who
showed expressive and receptive language areas dissociated into bilateral hemispheres.
The results demonstrated that this noninvasive and repeatable method is not only highly
reliable in determining language dominance, but it can also locate the expressive and
receptive language areas separately. The authors suggested that the method is a potent
alternative to the invasive procedures of the Wada test and is useful in treating patients
with brain lesions.
3.5.4 Magnetic Orientation for Tissue Engineering
The effects of magnetic fields, in particular, SMFs, on magnetic orientation for tissue
engineering have been reported (see the review by Ueno, Sekino, and Ogiue-Ikeda
2006). That is, the magnetic control of living cells using magnetic force may translate
into potentially viable tissue and promising medical engineering applications including
nerve regeneration. In this case, recognition of the role of diamagnetic, paramagnetic,
and ferromagnetic materials in vitro and in vivo may help in unraveling the underlying
mechanisms.
Umeno and Ueno (2003) examined the effect of strong SMFs on adherent cells. The
previous study by Iwasaka and Ueno (2003) showed that smooth muscle cells cultured
in 8- or 14-T superconducting magnets for three days exhibited orientational order parallel to the magnetic field direction. To discuss the process and the mechanism of this
orientation, the authors investigated the orientational characteristics of the cell culture
with quantitative measurements: an orientational order parameter and the FT analysis.
The orientational order parameter indicated the degree of orientation. The value of the
parameter was estimated with the FT of microscopic images. The cells cultured under
stronger SMFs exhibited stronger ordering, when they were cultured under a strong
magnetic gradient force of 400 T 2 /m. By contrast, they showed weaker ordering in the
control. The ordering was enhanced under uniform, strong magnetic fields, whereas it
was not affected or was suppressed by strong gradient forces. The authors suggested that
the cells organize themselves to minimize their diamagnetic torsion stresses, which can
be induced in the uniform magnetic fields by the membrane’s diamagnetic anisotropy.
In contrast to the estimation of torque force induced by a uniform SMF, the intense
inhomogeneous SMF acting on diamagnetic materials can generate a strong magnetic
force. Qian et al. (2009) have developed a superconducting magnet platform with largegradient high magnetic field (LG-HMF), which can produce three magnetic force fields
of −1360, 0, and 1312 T 2 /m and three corresponding apparent gravity levels of 0, 1, and
2 g for diamagnetic materials. The authors investigated the effects of different magnetic
force fields on osteoblast-like cell (MG-63 and MC3T3-E1) viability, microtubule actin
cross-linking factor 1 (MACF1) expression, and MACF1’s association with cytoskeleton.
Results showed that cell viability increased to different degrees after 24 hours of exposure to 0 or 1 g conditions, whereas it decreased by about 30% under 2 g conditions
compared with the control conditions. An increase in MACF1 expression at the RNA
or protein level was observed in osteoblast-like cells under the LG-HMF of −1360 T 2 /m