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The reaction of Ca(PO4)2O (TTCP) and CaHPO4 (DCPA) in an aqueous solution has been shown to be responsible for the hardening of a calcium phosphate cement. This reaction was investigated by monitoring pH changes and composition of solid phases. In the first set of experiments (no attempt to control pH), 2.5 g each of mixtures of TTCP/DCPA, molar ratio from 0.25 to 2, was placed in 12.5 mL of 0.15 mol/L KCl solution, at initial pH about 7, and the pH was allowed to drift for 24 h. Results show that at any time up to 24 h, the pHs were higher for slurries with higher TTCP/DCPA molar ratios. For the slurries with TTCP/DCPA molar ratio of ≥ 0.83, the 24 h pHs of the slurries were 9 to 11, whereas for those with TTCP/DCPA of ≤ 0.67, the pHs were between 5.3 and 7. The slurries with TTCP/DCPA molar ratios between 0.5 and 1 (Ca/P molar ratio=1.5 to 1.67) reacted completely within 24 h to form hydroxyapatite(OHAp), Ca5(PO4)3OH. In the second set of experiments, 2 g of an equimolar TTCP and DCPA mixture was placed in 20 mL of 0.15 mol/L KCl solution. The pH values were kept constant (6, 8 or 10) by using H3PO4 and Ca(OH)2 or HCl and KOH as titrant solutions. At pH 8, DCPA and TTCP dissolved at about the same rate, whereas at pH 10, DCPA was consumed more rapidly than TTCP. At both pHs, OHAp was the only product formed. However, at pH 6, the composition of reaction products depended on the types of the titrants used. Specifically when H3PO4 and Ca(OH)2 were used, hydrolysis of TTCP was the predominant reaction and both octacalcium phosphate and OHAp were formed. But, when HCl and KOH were used, only OHAp was formed. In this case hydrolysis of TTCP and DCPA appeared to proceed independently with TTCP hydrolysis beginning immediately and progressing slowly through 48 h while the DCPA hydrolysis began several hours after the reaction started but was completed in 24 h. ©2000 Kluwer Academic Publishers [ABSTRACT FROM AUTHOR]

This report describes the clinicopathological findings of a case of sporadic amyotrophic lateral sclerosis (ALS) resembling primary lateral sclerosis (PLS). A Japanese man developed muscle weakness in the distal part of the right upper extremity at age 59. At age 60 he presented with bradycinesia and rigidity. A neurological examination revealed fasciculation and increased deep tendon reflexes in the extremities. He developed decubitus and vesicorectal disturbance 2 months before his death at age 61. The neuropathological examination revealed not only prom-inent degeneration of the pyramidal tracts, evident in the internal capsule, but also loss of Betz’s cells in the motor cortex. There was relative preservation of the neurons in the hypoglossal nuclei and anterior horns of the cervical and lumbar cord. In the anterior horn of the first sacral cord, there were small aggregates of lipofuscin-laden macrophages in locations from which large cells had presumably been lost. Bunina bodies and ubiquitin-immunoreactive neuronal inclusions were present in the anterior horn cells of the spinal cord. On the basis of these clinicopathological findings, we concluded that this case was one of sporadic ALS with predominant involvement of the upper motor neuron system and exhibiting features of PLS. [ABSTRACT FROM AUTHOR]

In order to clarify the mechanism for erosion of glass-ionomer cements, we immersed two commercial luting cements in an acidic buffer solution under various conditions. The amounts of F, Al, Si, and Ca elated from the cement were (1) in proportion to the square root of immersion time, (2) unrelated to shape or volume of the sample, (3) dependent on its surface area, and (4) not affected by shaking of the solution. It was concluded that the dissolution was controlled by the diffusion of those species in the cement matrix, which was influenced by the structure of the matrix and the concentration of HI ion at the cement surface. The unrelated glass particles near the cementsurface were dissolved by the long immersion, and many pores were left in the surface region. [ABSTRACT FROM AUTHOR]

Decomposition of gypsum bonded investments was investigated by means of TG-DTA and X-ray diffraction. The decomposition began at about 900°C and led to the formation of CaSiO3 as a major product and Ca2SiO4 as a minor one. CaO was not formed during the decomposition of any of the investments. The decomposition process followed Jander's equation, [1-(1-α)1/3]2 = kt, and the Ca2+ ion diffusion in CaSiO3 was concluded to be a rate-determining step. [ABSTRACT FROM AUTHOR]

Introduction: Estimating the serum vancomycin (VCM) concentrations of lean and patients with obesity is challenging. Additionally, VCM dosing for Japanese patients undergoing hemodialysis remains particularly unclear. This study aimed to determine the impact of the physical build on serum VCM concentrations of Japanese patients undergoing hemodialysis., Methods: This retrospective cohort study included hospitalized patients undergoing hemodialysis, who received treatment with VCM between May 1, 2019, and December 31, 2021, at Kansai Rosai Hospital, which is a 642-bed acute care hospital in Japan. Patients were divided into the following three groups based on their body mass index (BMI): lean group (≤18.5 kg/m 2 ), normal group (18.5-25 kg/m 2 ), and obese group (≥25 kg/m 2 ). The VCM dose and predialysis serum VCM concentration (PVC) were compared., Results: This study included 191 patients. There were 50 patients in the lean group, 85 in the normal group, and 56 in the obese group. The median loading doses per body weight were 24.0, 22.1, and 21.2 mg/kg for the lean, normal, and obese groups, respectively. The VCM dose per body weight decreased significantly with increasing BMI. The median PVCs of the lean and normal groups were approximately 15 mg/L (not significantly different). However, the median PVC of the obese group was 18.3 mg/L, which was significantly higher (P < 0.001)., Conclusions: The VCM dose per body weight for Japanese patients undergoing hemodialysis should be adjusted based on the BMI., Competing Interests: Declaration of competing interest None., (Copyright © 2024 Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases, and Japanese Society for Infection Prevention and Control. Published by Elsevier Ltd. All rights reserved.)

Mus minutoides is one of the smallest mammals worldwide; however, the regulatory mechanisms underlying its dwarfism have not been examined. Therefore, we aimed to establish M. minutoides induced pluripotent stem cells (iPSCs) using the PiggyBac transposon system for applications in developmental engineering. The established M. minutoides iPSCs were found to express pluripotency markers and could differentiate into neurons. Based on in vitro differentiation analysis, M. minutoides iPSCs formed embryoid bodies expressing marker genes in all three germ layers. Moreover, according to the in vivo analysis, these cells contributed to the formation of teratoma and development of chimeric mice with Mus musculus. Overall, the M. minutoides iPSCs generated in this study possess properties that are comparable to or closely resemble those of naïve pluripotent stem cells (PSCs). These findings suggest these iPSCs have potential utility in various analytical applications, including methods for blastocyst completion., (© 2024. The Author(s).)

Mouse embryos in the early-implantation stage require manipulation under a microscope. While the extraction of DNA, RNA and proteins from a single sample allows for both determination of genetic type and analysis of gene expression, whole mount analysis is not possible. In this study, we explored the applicability of PCR using extraembryonic tissues, especially the decidual side tissue after isolating the embryos from implantation sites to establish a method for determining the genetic type of embryos. The implantation site was resected at each day from the date of vaginal plug confirmation, separated into embryos and deciduae. Genomic DNA were isolated separately from the embryos and the deciduae. PCR was performed using these genomic DNA, and the band patterns were compared after electrophoresis. As a result, we demonstrated that detecting embryo-derived cells in the decidua allows determination of the sex and presence of transgenes without harming the mouse embryos themselves, from 8.5 days of age. This method enables the determination of the genetic type of mouse embryos without damaging. This technique would expand the adaptations for analysis of mouse implanted embryos., (© 2023 Wiley-VCH GmbH. Published by John Wiley & Sons Ltd.)

The African pygmy mouse ( Mus minutoides ) displays a dwarfism phenotype distinctive from closely related species. This study aimed to investigate the growth hormone receptor (Ghr) gene sequence in M. minutoides . We identified several amino acid variations, including the P469L mutation. Our findings suggest that this mutation affects Ghr protein functionality, decreasing Igf1 expression and contributing to the dwarfism observed in M. minutoides . Further studies utilizing genome editing technology are necessary to elucidate the mechanisms involved in mammalian body size determination., Competing Interests: The authors declare that there are no conflicts of interest present., (Copyright: © 2023 by the authors.)