[in Japanese]

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The development of the head and neck skeletons is so complicated. In all vertebrates, the skeletons of the head and neck are made up of the chondrocranium, the sensory capsules, the membrane bone and the viscerocranium. In mammals, the chondrocranium ossifies to form the bone of the skull base. Membrane bones form the roof of the skull. Membrane bones directly ossify from the mesenchyme. Viscerocranium support the pharyngeal arches. In humans, there are six pairs of pharyngeal arches which contain a pair of cartilages. The fifth arch forms as short-lived rudiment which promptly regresses. In primitive vertebrates, the first arch cartilage called Meckel's cartilage gives rise to the bones of the upper and lower jaws. The jaws of higher vertebrate, including humans, are formed almost entirely by intramembranous ossification, and the cartilages of the first arch give rise to the incus and malleus in the middle ear. The cartilages of the second arch called Reichert's cartilage give rise to the stapes, the styloid process of the temporal bone, stylohyoid ligament and lesser horn of the hyoid bone. The cartilages of the third arch give rise to the greater horn of the hyoid bone. The cartilages of the forth and sixth arch fuse to form the thyroid, cricoid, arytenoid, corniculate and cuniform cartilages of the larynx.   This time, we made the model in order to demonstrate this complicated development. In this model, neurocranium, sensory capsules, viscerocranium and membrane bones painted in different colors respectively are placed on the board. The cartilages and bones are made of wood or paper clay, and disappearing or developing parts are detachable with the help of magnets. This model helps us to teach students the development of the branchial cartilages effectively.

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Activity of the sternocleidomastoid muscle, as one of the accessory inspiratory muscles, becomes remarkable when pulmonary diseases patients need muscular support for respiration in addition to the diaphragm. The present study inspected the relationship between the stages of emphysema and the size of sternocleidomastoid muscles with 42 voluntarily donated cadavers (average age 85.0 years). Severity of emphysema was evaluated by observation under a microscope, and by measurement of the long axis of pulmonary alveoli. The ratio of sectional areas of the sternocleidomastoid muscles to that of biceps brachii muscles was calculated, and was compared with the severity of emphysema for each cadaver. Among the female group with pulmonary diseases as the cause of death, the severity of emphysema showed a significant correlation to the sectional area ratio of sternocleidomastoid vs. biceps brachii muscles. This correlation was more obvious in women compared to men. This data suggests that the severity of emphysema can be predicted by observing the sternocleidomastoid muscles on the patients' body surface.

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At Shiga University of Medical Science, we have recently started practice visits to human dissection classes for co-medical students. As the number of co-medical schools that including an increase in human dissection classes, various problems are therefore expected to occur. We therefore established an educational method to optimize the effectiveness of such classes. For PT / OT students and the attending teachers who participated in dissection classes in 2010, we conducted an investigation regarding the efficacy of our teaching method. According to the survey results, many favorable opinions were obtained about our presentation and seminar methods, in which we showed the learning points in advance of the dissection classes. Such learning was found to not only increase student motivation, but it also enabled students to better understand the cadaver donation system.  These classes are taught to students the importance of maintaining privacy and secrecy at the highest levels. Therefore, it became clear that our teaching methods, for PT / OT students, to be extremely effective. According to this survey, many PT/OT students preferred locomotor system oriented training, and requested an increase in the length of time for such dissection classes. We therefore plan to continually improve on the our program so that PT / OT students may obtain the most benefits from such human dissection classes.

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A novel function of heparin has been found to enhance cellular adhesion and suppression of the growth of tumor cell colonies mediated by the binding of heparin to a kringle domain of urokinase-type plasminogen activator (uPA) -receptor on cell surfaces. Our present study was to evaluate the effect of heparin on tumor cell invasion and metastasis by computer-simulations with Fick's diffusion equation as well as with gradient percolation. The distribution of both the cellular and computer-emerged colonies were not random but heterogeneous during the formation of colonies. Our numerical analysis by Fick's equation demonstrated that the increment of the amount of heparin allows the decrease of diffusion constant (D) and thus cells are not capable of migration suggesting that heparin suppressed tumor cell invasion and metastasis.

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