Masao Onodera

Th1 biased response to a novel Porphyromonas gingivalis protein aggravates bone resorption caused by this oral pathogen.

In previous studies we showed that biasing the immune response to Porphyromonas gingivalis antigens to the Th1 phenotype increases inflammatory bone resorption caused by this organism. Using a T cell screening strategy we identified eight P. gingivalis genes coding for proteins that appear to be involved in T-helper cell responses. In the present study, we characterized the protein encoded by the PG_1841 gene and evaluated its relevance in the bone resorption caused by P. gingivalis because subcutaneous infection of mice with this organism resulted in the induction of Th1 biased response to the recombinant PG1841 antigen molecule. Using an immunization regime that strongly biases toward the Th1 phenotype followed by challenge with P. gingivalis in dental pulp tissue, we demonstrate that mice pre-immunized with rPG1841 developed severe bone loss compared with control immunized mice. Pre-immunization of mice with the antigen using a Th2 biasing regime resulted in no exacerbation of the disease. These results support the notion that selected antigens of P. gingivalis are involved in a biased Th1 host response that leads to the severe bone loss caused by this oral pathogen.

Long root of deciduous anterior teeth

A 24-year-old female Japanese patient presented with remarkably long roots of retained deciduous anterior teeth and permanent anterior teeth in the upper and lower jaw. Four lower anterior teeth were extracted for esthetic reasons. The patient had no apparent clinical syndrome related to the teeth or jaw, nor did there appear to be a family history of this condition. The extracted teeth and their lengths were as follows: the lower right deciduous lateral incisor was 25.55 mm long (root length, 18.95 mm); the lower left deciduous lateral incisor was 22.10 mm long (root length, 17.25 mm); the lower right deciduous canine was 27.95 mm long (root length, 20.60 mm); and the lower left deciduous canine was 23.90 mm long (root length, 17.65 mm).

Lymphatic Vessels as a Selective Administration Route of Antitumor Agent

Enucleation of primary lesion and neck dissection of regional lymph nodes are required in operating on a tumor. As a result, rehabilitation is very difficult following treatment of a tumor, because of the large defect and the side effects. The dissection of regional lymph nodes is required in the operation of mammary cancer and uterine cancer, causing edema of the limb. In other words the quality of life of a patient is adversely affected by current surgical methods. This has been improved by the use of Sentinel navigation surgery, but it is reported that this method is impossible to use in the head and neck region due to the existence of the lymphatic network. We surmised that the quality of life of the patient could be maintained by using the lymph vessels as a drug delivery route after involving the lymphatic network. From our past reports [1–4], we are able to elucidate, to a great extent, the detailed architecture of lymphatic vessels in the tongue. However, the network of the lymph nodes in the neck region is very complicated and at present is far from being elucidated. On the other hand, the lymph vessels from every organ connect with the regional lymph nodes as stated in the theory of Sentinel navigation