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71.
Ryuichi Kita Naoshi Nishida Yoshihiro Fukuda Hidemasa Azechi Yoko Matsuoka Toshiki Komeda Takehiro Sando Kazuwa Nakao Kanji Ishizaki 《International journal of cancer. Journal international du cancer》1996,67(2):176-180
We examined the genomic status of the p16INK4A (inhibitor of cyclin-dependent kinase 4 A) and cyclin-dependent kinase 4 (CDK4) genes in 62 human hepatocellular carcinomas (HCCs), 5 cholangiocellular carcinomas and 6 cell lines derived from human liver cancers. Although no samples showed the homozygous deletion of the p16INK4A gene, we detected intragenic mutations of the p16INK4A gene in 3 HCCs and one HCC cell line, which led to an amino-acid substitution or a frameshift. In 2 HCC samples with mis-sense mutations of the p16INK4A gene, loss of heterozygosity on 9p22 was also detected, suggesting that the loss of function of p16 was induced during hepatocarcinogenesis. On the other hand, amplification or rearrangement of the CDK4 gene was not detected in any samples examined in this study. These results indicated that the mutations or deletions of the p16INK4A gene are not frequent, but may play a role in a sub-set of human HCC. © 1996 Wiley-Liss, Inc. 相似文献
72.
Kikuaki Yoshida Ayaka Sakaki Yoriko Matsuyama Toshiki Mushino Masanori Matsumoto Takashi Sonoki Shinobu Tamura 《Internal medicine (Tokyo, Japan)》2022,61(3):407
A 57-year-old man without underlying diseases presented with fatigue, loss of appetite, and jaundice 1 week after receiving the first dose of the BNT162b2 mRNA coronavirus disease 2019 (COVID-19) vaccine and showed hemolytic anemia with fragmented erythrocytes and severe thrombocytopenia 2 weeks after receiving the vaccine. An a disintegrin-like and metalloproteinase with thrombospondin type 1 motifs 13 (ADAMTS13) activity level of <10% and ADAMTS13 inhibitor positivity confirmed the diagnosis of acquired thrombotic thrombocytopenic purpura (TTP). Combination therapy with plasma exchange, corticosteroid, and rituximab improved the clinical outcome. We herein report the first Japanese case of TTP possibly associated with vaccination. Physicians should be alert for this rare but life-threatening hematological complication following COVID-19 vaccination. 相似文献
73.
Yuki Wada Toshiki Akiyama Kazuo Harada Tetsuo Honma Hiroshi Naka Susumu Saito Mitsuiro Arisawa 《RSC advances》2021,11(36):22230
A novel platinum nanoparticle catalyst closely located near the surface of titanium oxide, PtNP/TiO2, has been prepared. This catalyst has both the properties of a photocatalyst and a metal nanoparticle catalyst, and acquired environmentally friendly catalytic activity, which cannot be achieved by just one of these catalysts, to afford ethers from benzyl alcohols under the wavelength of 420 nm.A novel platinum nanoparticle catalyst closely located near the surface of titanium oxide, PtNP/TiO2, has been prepared. It has catalytic activity to afford ethers from benzyl alcohols under the wavelength of 420 nm.The electrolysis of water by a heterogeneous metal oxide semiconductor (MOS) photocatalyst, called the Honda–Fujishima effect,1 received considerable attention because it enables the conversion of solar energy. As a result, photoreactions by heterogeneous photocatalysts based on MOS have been reported until now, including numerous practical applications such as carbon dioxide reduction2 and pollutant removal.3Research on photocatalytic reactions using visible light is progressing steadily. Among them, TiO2 has been extensively studied due to its high catalytic activity, low cost, non-toxicity, and long-term stability.4,5Titanium oxide has a very strong oxidizing power, but it does not have a strong reducing power.6 By using a transition metal such as platinum on titanium oxide as a support, its reducing power can be increased, and the amount of hydrogen generated in the electrolysis of water can be improved eight times compared to the case of titanium oxide alone.7Furthermore, when MOS contacts the metal, a potential barrier called Schottky barrier is formed at the interface. The basic characteristic of this Schottky barrier lies in the Schottky barrier height (Φ), which represents the difference between the CB of the MOS distorted by the contact with a metal and the Fermi level (EF) of the metal. Although it has been studied for almost half a century, how to determine the barrier is still not well understood. Due to the formation of the Schottky barrier height, the energy required to move the electrons from the valence band of MOS to the conductor changes from Eg to Φ, and the energy becomes smaller and it changes to a longer wavelength. As a result, a photoreaction with titanium oxide using light with a wavelength longer than 387 nm has also been reported (Scheme 1)8Open in a separate windowScheme 1Effect of sunlight exposure on aerobic oxidation of alcohols with the Pt/TiO2 catalysts.On the other hand, we have recently developed a sulfur-modified Au-supported Pd NP catalyst (SAPd) that is applicable in Suzuki–Miyaura coupling9a,9b and C–H functionalization9c (Scheme 2a). It was constructed by approximately 10 layers of self-assembled Pd(0) NPs (mean size: <5 nm) supported on a sulfur-modified Au surface. We speculated that the self-assembled Pd NPs, which were encapsulated in a sulfated p-xylene polymer matrix,9d were formed using in situ metal NP and nanospace simultaneous organization (PSSO), as illustrated in Scheme 2b: (i) the reduction of a high-valence metal source, (ii) growth of transition metal NPs, (iii) growth of a matrix with appropriately sized nanopores, and (iv) encapsulation of the metal NPs in these nanopores. To prepare SARu,10 SANi,11 SAFe(ii),12 and SAFe(0)13 (Scheme 2a), the PSSO method involves the in situ reduction of a noble metal precursor to produce in situ metal NPs.Open in a separate windowScheme 2(a) Preparation of SAPd, SARu, SANi, SAFe(II) and SAFe(0) by combining in situ PSSO with an organic reductant, (b) in situ metal nanoparticle and nanospace simultaneous organization (PSSO) method and the image of the SAPd structure and (c) the preparation of PtNP/TiO2.In this research project, we decided to create a novel metal NP catalyst having metal NPs near the surface of TiO2 by substituting the gold-supported SAPd for gold with a titanium oxide (TiO2) photocatalyst. Alternatively, by substituting the solid gold support for a photocatalyst, we thought that we could create a novel metal NPs catalyst with an unprecedented reactivity by combining the properties of both photocatalyst and metal nanoparticle catalyst (Scheme 2c). 相似文献
74.
75.
Ryota Amano Shuta Toru Michio Yamane Masanobu Kitagawa Katsuiku Hirokawa Toshiki Uchihara 《Neuropathology》2020,40(4):328-335
Marinesco bodies (MBs) are spherical nuclear inclusions found in pigmented neurons of the substantia nigra. Although MBs are abundant in senescent brains, how they are related to aging processes remains unclear. Here, we performed a morphometric analysis of midbrain pigmented neurons to identify the possible influence of MBs on nuclear size. The transected area of the nucleus (nuclear area) was larger in the presence of MBs and was correlated with the area of MB (MB area) in all tested brains. The MB-associated nuclear enlargement was significant even after MB areas were subtracted from nuclear areas. Moreover, higher MB immunoreactivity of p62 was detected in the nucleoplasm of the enlarged MB-associated nuclei. This study on human brains is the first quantitative approach demonstrating MB-associated nuclear enlargement and progressive accumulation of small nucleoplasmic materials. Although cellular hypertrophy is usually considered to be an indication of the upregulation of cellular function, this might not always be the case. These findings suggest that an age-related decline of ubiquitin-proteasome and autophagy system activity and stagnation of undegradable materials are one of the candidate mechanisms to explain the age-related decline of neural activity in the substantia nigra. 相似文献
76.
Kyoko Itoh Takashi Kasai Yukiko Tsuji Kozo Saito Ikuko Mizuta Yoshinori Harada Shinji Sudoh Toshiki Mizuno Masanori Nakagawa Shinji Fushiki 《Neuropathology》2014,34(3):309-313
Multiple system atrophy (MSA) is an oligodendrogliopathy of presumably sporadic origin, characterized by prominent α‐synuclein inclusions with neuronal multisystem degeneration, although a few Mendelian pedigrees have been reported. Here we report two familial cases of MSA of unknown genetic background. One patient was diagnosed as a possible MSA‐C (cerebellar dysfuntion) case, and the other as clinically possible MSA‐P (parkinsonism), which turned out to be definite MSA, based on a detailed autopsy. The neuropathology showed extensive deposition of α‐synuclein in the glia as well as in the neurons located in the cerebral cortices and hippocampal systems, although neither multiplication of the SNCA gene or mutations in COQ2 gene were identified in the family concerned. 相似文献
77.
Koichiro Irie Takaaki Tomofuji Daisuke Ekuni Yasumasa Endo Kenta Kasuyama Tetsuji Azuma Naofumi Tamaki Toshiki Yoneda Manabu Morita 《Archives of oral biology》2014
Objective
Previous studies have demonstrated the relationship between ageing and oxidative stress. In this study, we examined the effects of topical application of a dentifrice containing anti-oxidative, anti-inflammatory, and anti-bacterial agents (Tomarina®) to the gingival surface on gingival collagen degradation in rats.Design
Fischer 344 male rats (4 or 8 months old) were divided into two groups: experimental group and control group. Tomarina® (the experimental group) or control dentifrice (the control group) was applied 5 days per week for 2 months.Results
In the control group, gingival collagen density decreased with ageing. In the experimental group, the collagen density did not change with ageing, and was greater than that in the control group at 10 months of age (p < 0.0083). In addition, the control group showed an increase in serum oxidative stress with ageing. The experimental group also showed increased serum oxidative stress, but the value was lower than the control group at 10 months of age (p < 0.0083). Furthermore, low expressions of protein oxidative damage in the periodontal tissue were observed in the experimental group, compared to the control group at 6 months and 10 months.Conclusion
These findings indicate that Tomarina® might suppress the effects of ageing on gingival collagen degradation, by decreasing oxidative stress in the rat model. 相似文献78.
79.
80.
Ako E Morisaki T Hasegawa T Hirakawa T Tachimori A Nakazawa K Yamagata S Kanehara I Nishimura S Taenaka N 《Surgical laparoscopy, endoscopy & percutaneous techniques》2010,20(6):e226-e229
Intussusception is rare in adults and it is difficult to diagnose on admission. We present the case of a 43-year-old woman with the chief complaint of nausea and upper abdominal pain. Abdominal multidetector-row computed tomography showed ileo-ileal small bowel intussusception with an intraluminal soft tissue mass with attenuation numbers suggestive of a lipoma. The patient was treated with a laparoscopic-assisted extracorporeal partial resection of the small bowel including ileal lipoma, followed by a functional end-to-end anastomosis. Histologic diagnosis of the resected tumor, 2.4×2.0×2.0 cm, was an intestinal lipoma. This case serves as the basis of a review of small bowel intussusception in adults secondary to lipomas. It focuses on the utility of multidetector-row computed tomography and the cosmetic, physical, and economic benefits of laparoscopic surgery as well as the rarity of the disease. 相似文献