Adenoid cystic carcinoma(ACC) is one of the most common malignant tumors of minor salivary glands and can also arise in a variety of sites in the head and neck including the major salivary glands, the esophagus, the lacrimal glands. ACC shows slow but relentless growth, so it shows long-term recurrence. The various reports about prognostic factors which influence the recurrence pattern are introduced but the reports about prognostic factors are rare in Korean adenoid cystic carcinoma patients. We examined 40 ACC patients who finally diagnosed at Department of Oral Pathology, Seoul National University Dental Hospital. Clinicopathologic and immunohistochemical features were reviewed and factors correlated with recurrence and survival were analyzed. The 5-year survival rate of T3,T4 stage was 31.2%, while that of the T1,T2 stage was 88.2%, and the difference 5-year survival and T stage was statistically significant. The rate of local recurrence was 20% and the rate of distant metastasis was 27.5%. Mean recurrence time were 4.8 years and 5.2 years. There was no significant difference between age, sex, T stage, TNM stage, histologic type and recurrence. But the high T stage and the solid type recurred more frequently. There was no significant difference between recurrence rate, 5-year survival rate and Ki-67, MVD expression. But the higher expression of Ki-67, MVD show the higher recurrence rate and the lower 5-year survival rate

We manufactured the metal hydrides of using a very easy and cheap way that Ti-12%Mg blending powder was mechanically milled with liquid milling media such as isopropyl alcohol (, containing oxygen) and hexane (, no oxygen) as hydrogen source. The synthesized in isopropyl alcohol contained the high oxygen of 11.2%, while one in hexane had the low oxygen content of 0.7%. Such a difference of oxygen content affected the dehydriding behavior, phase transformation, and microstructural evolution at high temperature, which was investigated through X-ray diffraction and DSC measurements, and electron microscope observations

The particle reinforced composite fabricated by a powder-in sheath rolling (PSR) method was severely. deformed by the accumulative roll-bonding (ARB) process. The ARB process was performed up to 8 cycles at ambient temperature without lubricant. The ARBed composite exhibited an ulbricant. grained structure similar to the other ARBed bulky materials. Tensile strength of the composite increased gradually with the number of ARB cycles, but from the 6th cycle it rather decreased slightly. These characteristics of the composite were somewhat different from those of Al powder compact fabricated by the same procedures. The difference in microstructure and mechanical properties between Al powder compact and the composite was discussed

The alumina dispersion-strengthened (DS) C15715 Cu alloy fabricated by a powder metallurgy route was annealed at temperatures ranging from in the air and in vacuum. The effect of the annealing on microstructural stability and room-temperature mechanical properties of the alloy was investigated. The microstructure of the cold rolled OS alloy remained stable until the annealing at in the air and in vacuum. No recrystallization of original grains occurred, but the dislocation density decreased and newly formed subgrains were observed. The alloy annealed at in the air experienced recrystallization and grain growth took place, however annealing in vacuum at did not cause the microstructural change. The mechanical property of the alloy was changed slightly with the annealing if the microstructure remained stable. However, the strength of the specimen that was recrystallized decreased drastically.

Odontogenic ghost cell tumor (OGCT) is considered as a neoplastic counterpart of the calcifying odontogenic cyst (COC). β-catenin mutations have been described in COC suggesting a critical role in its histogenesis. In this study, we report a patient with OGCT contains a missense mutation on codon 3 (ACT -> TCT). Immunohistochemistry showed nuclear, cytoplasmic, and membranous accumulation of β-catenin in the tumor cells. TUNEL assay showed positive signals in nucleated cells adjacent to the ghost cells. Our data suggest that β-catenin plays an important role in the tumorigenesis of OGCT. OGCT may developed by improper differentiation process coordinated by WNT signaling pathway. Further studies are needed to determine a genotypic/phenotypic characteristics of ghost cell containing odontogenic lesions.

In order to obtain novel genes related to the human craniofacial development, molecular cloning and sequencing, and in situ hybridization using craniofacial tissue sections were performed and followed by protein structure simulation. Totally 231 clones were obtained from the subtracted craniofacial tissue cDNA library of human embryo. Random cloning using the non-redundant clones from the craniofacial tissue of human embryo was done and obtained 398 clones from the premade human chondrocyte cDNA library. Their partial sequence data showed that 214 clones of subtracted cDNA library of craniofacial tissue were still non-redundant in Genebank search. And 20 clones among 498 clones of premade chondrocyte cDNA library were known to be undefined genes. Through in situ hybridization screening in the craniofacial tissue sections of 10 weeks old human embryo 36 clones were found to be positive in specific tissues. Depending on the cell types of sirnilar developmental origin, the positive reactions could be divided into five groups. Among the 20 clones of undefined genes from human chondrocyte cDNA library, 7 clones showed characteristic positive reaction in human cartilage tissue by in situ hybridization. From the simulated protein structure, motif analysis and in situ hybridization studies for the 7 undefined clones, Ch89, Ch96, Ch129, Ch285 clones may function in the outer space of the cell constituting a part of matrix protein complex, and Ch276 as a transmembrane protein which might partic ipate in matrix calcification around chondrocytes. Ch153 is a kind of antirnicrobial protein also acting as an inflammation mediator, and Ch334 clone is a zinc finger protein, of which expression increases in human adult tissues We presume these novel genes from human chondrocytes may provide a new path of chondrocyte development and functions of human craniofacial tissues