2006, Vol.19, No.2

Anatomy & Biological Anthropology 2023 KCI Impact Factor : 0.33

pISSN : 2671-5651 / eISSN : 2671-566X
https://journal.kci.go.kr/aba

Radiographic research was performed to know the frequency of two-phalanged fifth toe and its relation to presence of the ossification centers in normal Korean children. Previous study showed more than 74% of the incidence in adulthood and less than 30% in childhood. Fifty children (33 male and 17 female, aged 2 to 15; mean age 9.6) were studied by plain foot radiographs focused on the fifth toe. In the 3~8 yr old 20 subjects, secondary ossification center of distal phalangeal bone was seen as a ossicle (small bone) placed at proximal to the distal phalanx. Secondary ossification center of middle phalangeal bone and the bony shaft of the phalanx was hard to distinguish. So keeping up the objectivity, regardless of distinguishable ossification center or the bony shaft of phalanges, ossicles seen on the 5th toe was counted to classify the presumptive type of the toe. Epiphyseal ossification center of proximal phalanx was excluded from the count. There were three types of the fifth toe which has 2 ossicles to 4 ossicles. Overall incidence of the type of 2 ossicles was 24% (12/50). Above 12 yr old group the incidence was 61% (11/18), and above 13 yr old group the incidence was 75% (9/12). The incidence of biphalangism came closer to the adult’s after late childhood. This finding represent that progress of biphalangealization completed after late childhood. It seems that the progress starts earlier than 3 yr old. We made the hypothesis by the incidence of 30% (6/20) of the type which has 4 ossicles on the fifth toe at 3~8 yr old group. Four ossicles might be a secondary ossification center of distal phalanx and the bony shaft of distal, middle and proximal phalanx. They might form a distal interphalageal joint and the triphalangeal toe. To know more about the morphogenesis of biphalalngeal 5th toe, further progressive study in childhood is needed.

Ionizing radiation exerts harmful effect during the limb development, but the exact mechanism is still largely unknown. In this study, 2 Gy of X-ray irradiated to the rat fetuses on gestation day of 13.7 when the hindlimb buds appear, and sacrificed at GD 14.7, GD 15.7 and GD 16.7, respectively. To reveal the changes of apoptotic figures between control and experimental groups, TUNEL immunohistochemistry and confocal laser scanning microscopy were carried. Mean body weight of fetuses of irradiated groups were decreased significantly compared to the control group. Numerical digit anomalies and asymmetries between right and left sides were increased significantly in the irradiated group compared to control group. Some digit anomalies were increased significantly in the right side. Radiation-induced decrement of the density of apoptotic figures on GD 14.7 was presumed to be related with foot and digit anomalies.

Cardiac dendritic cells are considered to play an important role in the immunoresponse of the heart. However, It is unknown that changes of shapes and numbers of these cells in the heart. The aim of this study is to reveal age-related changes of MHC class II positive dendritic cells in cardiac muscle of rat. Male Sprague-Dawley rats (1 month, 12 months, and 24 months old) were used in this study. Animals were deeply anesthetized with 3.5% chloral hydrate (1 mL/100 g) and hearts removed. Immunostaining was done according to standard methods used routinely. In brief, tissue sections were incubated with primary antibodies generated in mouse anti-rat MHC class II antibody for single immunostains. Tissue sections were observed by using light microscope and dendritic cells were counted. Average numbers of MHC class II-positive dendritic cells were 1.4 cells per unit area (0.2 mm2) at 1 month old rat, 2.8 cells at 12 months old rat, and 4.6 cells at 24 months old rat, and then numbers of dendritic cells were increased according to ages. According as age increases, cytoplasmic processes of MHC class II-immunoreactive dendritic cells became longer and more complex and aggregated together. It’s suggested that age-related changes of MHC class II positive dendritic cells in the cardiac muscle would be related to immunity.