Photoinduced hydrogen release from hydrogen boride sheets

Hydrogen boride nanosheets (HB sheets) are facilely synthesized via ion-exchange treatment on magnesium diboride (MgB2) in an acetonitrile solution. Optical absorption and fluorescence spectra of HB sheets indicate that their bandgap energy is 2.8 eV. According to first-principles calculations, optical absorption seen at 2.8 eV is assigned to the electron transition between the sigma-bonding states of B and H orbitals. In addition, density functional theory (DFT) calculations suggest the other allowed transition from the s-bonding state of B and H orbitals to the antibonding state with the gap of 3.8 eV. Significant gaseous H-2 release is found to occur only under photoirradiation, which causes the electron transition from the s-bonding state to the antibonding state even under mild ambient conditions. The amount of H-2 released from the irradiated HB sheets is estimated to be 8 wt%, indicating that the sheets have a high H-2-storage capacity compared with previously reported metal H-2-storage materials

An Up-to-Date Anti-Cancer Treatment Strategy Focusing on HIF-1α Suppression: Its Application for Refractory Ovarian Cancer

Hypoxia inducible factor-1α (HIF-1α) predominantly determines the transcriptional activity of HIF-1, which induces the certain genetic expressions to participate in the proliferation and progression of the tumor. It is supposed that HIF-1α is also an extremely important factor in cancer treatment. Based on the results of our recent analyses using ovarian tumors, which indicated the close association of HIF-1α expression with the acquisition of malignancy and the characterization of histology, we further investigated the possibility of a new strategy of cancer therapy that targeted HIF-1α inhibition in the ovarian carcinoma. The cell line HUOCA-II, which originates from the refractory ovarian clear cell adenocarcinoma, was treated with rapamycin. The inhibitory effect of HIF-1α was analyzed by immunohistochemistry and western blotting. It was demonstrated that inhibition of HIF-1α and vascular endothelial growth factor (VEGF) expressions would lead to the down-regulation of tumor cell proliferation. Interestingly, there was little or no change in GLUT-1 expression by rapamycin administration. Thus, the inhibition of GLUT-1 may also be a key for the new strategy of cancer therapy as well as HIF-1α and VEGF

The Japan Monkey Centre Primates Brain Imaging Repository of high-resolution postmortem magnetic resonance imaging: the second phase of the archive of digital records

超高磁場MRIで見る霊長類「全脳」神経回路の多様性 --分野横断型の霊長類脳標本画像リポジトリ：ヒト脳と精神・神経疾患の理解を加速する国際研究基盤--. 京都大学プレスリリース. 2023-05-22.A comparison of neuroanatomical features of the brain between humans and our evolutionary relatives, nonhuman primates, is key to understanding the human brain system and the neural basis of mental and neurological disorders. Although most comparative MRI studies of human and nonhuman primate brains have been based on brains of primates that had been used as subjects in experiments, it is essential to investigate various species of nonhuman primates in order to elucidate and interpret the diversity of neuroanatomy features among humans and nonhuman primates. To develop a research platform for this purpose, it is necessary to harmonize the scientific contributions of studies with the standards of animal ethics, animal welfare, and the conservation of brain information for long-term continuation of the field. In previous research, we first developed a gated data-repository of anatomical images obtained using 9.4-T ex vivo MRI of postmortem brain samples from 12 nonhuman primate species, and which are stored at the Japan Monkey Centre. In the present study, as a second phase, we released a collection of T2-weighted images and diffusion tensor images obtained in nine species: white-throated capuchin, Bolivian squirrel monkey, stump-tailed macaque, Tibet monkey, Sykes’ monkey, Assamese macaque, pig-tailed macaque, crested macaque, and chimpanzee. Our image repository should facilitate scientific discoveries in the field of comparative neuroscience. This repository can also promote animal ethics and animal welfare in experiments with nonhuman primate models by optimizing methods for in vivo and ex vivo MRI scanning of brains and supporting veterinary neuroradiological education. In addition, the repository is expected to contribute to conservation, preserving information about the brains of various primates, including endangered species, in a permanent digital form

Ganglioside metabolism in a transgenic mouse model of Alzheimer's disease: expression of Chol-1α antigens in the brain

The accumulation of Aβ (amyloid β-protein) is one of the major pathological hallmarks in AD (Alzheimer's disease). Gangliosides, sialic acid-containing glycosphingolipids enriched in the nervous system and frequently used as biomarkers associated with the biochemical pathology of neurological disorders, have been suggested to be involved in the initial aggregation of Aβ. In the present study, we have examined ganglioside metabolism in the brain of a double-Tg (transgenic) mouse model of AD that co-expresses mouse/human chimaeric APP (amyloid precursor protein) with the Swedish mutation and human presenilin-1 with a deletion of exon 9. Although accumulation of Aβ was confirmed in the double-Tg mouse brains and sera, no statistically significant change was detected in the concentration and composition of major ganglio-N-tetraosyl-series gangliosides in the double-Tg brain. Most interestingly, Chol-1α antigens (cholinergic neuron-specific gangliosides), such as GT1aα and GQ1bα, which are minor species in the brain, were found to be increased in the double-Tg mouse brain. We interpret that the occurrence of these gangliosides may represent evidence for generation of cholinergic neurons in the AD brain, as a result of compensatory neurogenesis activated by the presence of Aβ

Cutoff Values of Serum IgG4 and Histopathological IgG4+ Plasma Cells for Diagnosis of Patients with IgG4-Related Disease

IgG4-related disease is a new disease classification established in Japan in the 21st century. Patients with IgG4-related disease display hyper-IgG4-gammaglobulinemia, massive infiltration of IgG4+ plasma cells into tissue, and good response to glucocorticoids. Since IgG4 overexpression is also observed in other disorders, it is necessary to diagnose IgG4-related disease carefully and correctly. We therefore sought to determine cutoff values for serum IgG4 and IgG4/IgG and for IgG4+/IgG+ plasma cells in tissue diagnostic of IgG4-related disease. Patients and Methods. We retrospectively analyzed serum IgG4 concentrations and IgG4/IgG ratio and IgG4+/IgG+ plasma cell ratio in tissues of 132 patients with IgG4-related disease and 48 patients with other disorders. Result. Serum IgG4 >135  mg/dl demonstrated a sensitivity of 97.0% and a specificity of 79.6% in diagnosing IgG4-related disease, and serum IgG4/IgG ratios >8% had a sensitivity and specificity of 95.5% and 87.5%, respectively. IgG4+cell/IgG+ cell ratio in tissues >40% had a sensitivity and specificity of 94.4% and 85.7%, respectively. However, the number of IgG4+ cells was reduced in severely fibrotic parts of tissues. Conclusion. Although a recent unanimous consensus of all relevant researchers in Japan recently established the diagnostic criteria for IgG4-related disease, findings such as ours indicate that further discussion is needed

A new species of Labidocera (Copepoda, Calanoida, Pontellidae) collected from Okinawa, southwestern Japan, with establishment of five Indo-West Pacific species groups in the L. detruncata species complex

Labidocera churaumi sp. n. is described from Okinawa, southwestern Japan. The female of the new species differs from other congeners in genital compound somite with right postero-lateral and left antero-lateral processes. The male is distinguished from other congeners by the structure of the fifth leg. This new species is assigned to a newly proposed species group, the L. madurae species group, within the L. detruncata species complex. In this species complex five Indo-West Pacific species groups are recognized (cervi, detruncata, gangetica, madurae, and pavo) and defined on the basis of difference in sexual dimorphism