Design of Titanium Alloys Insensitive to Thermal History for Additive Manufacturing

Powder bed fusion is the most common technology used for 3D printing, where thermal energy is used to selectively melt/sinter granular materials into solid shapes. The build platform is then lowered, more powder is added, and the process is repeated for the next layer to fully print the design. As a result, the built-up part is repeatedly heated. Therefore, materials that are not sensitive to thermal history are preferred for this process. The Ti–Zr system forms a continuous solid solution for both β- and α-phases. The presence of Fe in Ti alloys is inevitable; however, it provides some beneficial effects. The purpose of this work was to prepare Ti–Zr–Fe alloys and investigate their heat treatment behaviour. Ti-xmass%Zr-1mass%Fe alloys (x = 0, 5, 10) were prepared with arc melting. The formation of a solid solution of Zr in Ti was confirmed on the basis of X-ray diffraction peak shifts and hardening effects. A small amount of β-phase precipitation was suggested by the change in electrical resistivity after isothermal ageing at 673 and 773 K. However, no obvious phase or microstructural changes were observed. The laser scanning increased the volume of the precipitates and also coarsened them, but the effect was limited.Ueda M., Ting Hsuan C., Ikeda M., et al. Design of Titanium Alloys Insensitive to Thermal History for Additive Manufacturing. Crystals 13, 568 (2023); https://doi.org/10.3390/cryst13040568

Activities of Tissue Registry and Tumor Registry in NAGASAKI Area

In Nagasaki area, registry of malignant tumor patients found in hospitals and clinics in the city has been conducted by the Nagasaki City Medical Association with the cooperation of Radiation Effects Research Foundation (RERF) since 1957. The method of diagnosis is various such as 1) autopsy, 2) microscopy, 3) cytologic diagnosis, 4) endoscopic examination findings, 5) operation, 6) radiography, 7) clinical findings, 8) death certificate and 9) others. The number of cases collected during the period of 19 years up to 1975 amounts to 41,780. On the other hand, tissue registry was started in September 1975. In this Registry, all hospitals in Nagasaki Prefecture and RERF where specimens and tissues are obtained and examined for diagnostic and therapeutic purposes are invited to participate. The purpose of the Tissue Registry is to register as many cases as possible occurring in the residents of Nagasaki prefecture and to promote diagnosis, treatment, early detection, and prevention of tumors by analyzing the collected data. Prior to the establishment of the Tumor Registry, it was agreed to provide the best possible tissue diagnosis, clarify incidence and site of tumors, and to provide a central depository where useful and confirmed diagnosis are available as a source of data for medical studies related to tumors. Fortunately, financial assistance was given to the establishment the Tissue Registry through RERF in accordance with a provision of the contract between the National Cancer Institute and the National Academy of Sciences, USA and thus the operation of the Tissue Registry has become available. At commencement of this project, we established two sub-committees ; Pathology Committee and Statistics Committee

A Functional Polymorphism in B and T Lymphocyte Attenuator Is Associated with Susceptibility to Rheumatoid Arthritis

Inhibitory coreceptors are thought to play important roles in maintaining immunological homeostasis, and a defect in the negative signals from inhibitory coreceptors may lead to the development of autoimmune diseases. We have recently identified B and T lymphocyte attenuator (BTLA), a new inhibitory coreceptor expressed on immune cells, and we suggest that BTLA may be involved in the development of autoimmune diseases using BTLA-deficient mice. However, the role of BTLA in the pathogenesis of autoimmune diseases in humans remains unknown. We, therefore, examined the possible association between BTLA and rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and Sjögren's syndrome (SS) by conducting a case-control genetic association study. We found that 590C single-nucleotide polymorphism (SNP) of BTLA gene was significantly associated with susceptibility to RA, but not to SLE or SS. Furthermore, RA patients bearing this 590C SNP developed the disease significantly earlier than the patients without this allele. We also found that BTLA with 590C allele lacked the inhibitory activity on concanavalin A- and anti-CD3 Ab-induced IL-2 production in Jurkat T cells. These results suggest that BTLA is an RA-susceptibility gene and is involved in the protection from autoimmunity in humans

An Autopsy Case of Biliary Cystadenocarcinoma of the Liver

Summary : An autopsy case of a 58-year-old female with biliary cystadenocarcinoma is presented. A large cyst occupied the entire left lobe of the liver associating with multilocular daughter cysts and solid lesion. Histologically, tumor showed papillary, back-to-back glandular, cribriform pattern in the inner surface of the cysts with stromal invasion. Polygonal atypical cells were arranged in cords and adenoid cystic pattern in the solid lesion. Immunohistochemically, EMA was stained in the tumor cells as well as normal hepatocytes. CEA was diffusely stained in the cytoplasm and luminar surfaces of the tumor cells, while CEA was stained only in the luminar surfaces of benign-appearing eptithelial cells of the cysts. Keratin and α-fetoprotein were not stained in the tumor cells. The origin of this tumor remains unknown, although transformation from congenital solitary cyst, biliary cystadenoma and reminiscence of cystadenoma of the pancreas or originally occurrence of cystadenocarcinoma in the liver are considered the basic histogenesis of cytadenocarcinoma of this case

Adamantinoma of the Tibia. - Report of a Case with Findings of Ultrastructural and Immunohistochemical Studies,

A case of tibial adamantinoma in a one-year and ten-month old girl is reported. She had gait disturbance and her roentogenogram showed a well circumscribed radiolucent area in the tibia. Light microscopic examination showed the epithelial component of nests and pseudoglandular arrays in the loose fibrous connective tissue. We finally diagnsed the tumor as adamantinoma of the tibia based on roentogenographical and histological findings. Moreover, the nature of the neoplastic cells was studied by the immunohistochemical and electron microscopic methods. The adamantinoma is regarded as a unique neoplasm capable of differen - tiating into epithelial elements as well as mesenchymal ones . Detection of epithelial component is important to differentiate from similar disorders. The fibrous dysplasia- like lesion in stroma is interpreted as a part of the spectrum of mesenchymal differentiation

A Comparative Study between CT and Histopathologic Findings of Amyloid Goiter

There are only a few reports describing the imaging features of amyloid goiter with adequate histopathologic correlation. We present a case of amyloid goiter, focusing the correlation between CT and autopsy specimen findings. CT showed diffuse low attenuation areas (40-50 H.U. ) which corresponded to the tissue with dense amyloid deposits. There was also focal areas of very low attenuation which contained the adipose tissue. The latter finding is relatively characteristic for amyloid goiter, because fatty infiltration is known to be frequently associated with amyloid goiter : a rare finding in other disorders