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41.
Yoshiyuki Kurata Machiko Oshida Hironori Take Takayasu Furubayashi Hirohisa Nakao Yoshiaki Tomiyama Yoshio Kanayama Nobuo Nagao Yasuto Okubo Takeshi Yonezawa and Seiichiro Tarui 《Vox sanguinis》1989,57(3):199-204
A new method was studied for eliminating HLA class I antigens from the surface of platelets without damaging the cells. Platelets were exposed to an acid solution (pH 3.0) to eliminate the antigenicity of HLA class I antigens. The reduction in antigenicities of HLA class I common antigen and individual HLA class I antigens by acid treatment was marked. Patients' sera which contained multispecific HLA antibodies reacted with PBS-treated platelets, but not with acid-treated platelets. No changes were observed in the antigenicities of glycoprotein Ib or glycoprotein IIb/IIIa. The viability of acid-treated platelets was 83%. Ultrastructural investigations revealed no significant difference between the PBS-treated platelets and acid-treated platelets. The platelet function studies showed that the aggregation of acid-treated platelets induced by various agonists was only slightly reduced compared with PBS-treated platelets. We propose that acid-treated platelets are promising for clinical use in patients refractory to platelet transfusions and may be superior to chloroquine-treated platelets for analysis of the specificity of antiplatelet antibodies. 相似文献
42.
Up-regulation of transferrin receptor 1 in chronic hepatitis C: Implication in excess hepatic iron accumulation. 总被引:3,自引:0,他引:3
Hiroyuki Saito Yoshinori Fujimoto Takaaki Ohtake Yasuaki Suzuki Shinobu Sakurai Yayoi Hosoki Katsuya Ikuta Yoshihiro Torimoto Yutaka Kohgo 《Hepatology research》2005,31(4):203-210
BACKGROUND/AIMS:: To clarify the mechanism of excess hepatic iron accumulation in chronic hepatitis C, we investigated the expressions of transferrin receptor 1 and divalent metal transporter 1 in hepatocytes, both of which are involved in cellular iron uptake, in relation to the degree of hepatic iron accumulation and hepatic fibrosis by immunohistochemistrical study. METHODS:: Forty-six hepatic tissues with chronic hepatitis C and five normal hepatic tissues were examined. Chemical detection of hepatic iron accumulation was performed by Perl's Prussian blue stain. The immunohistochemistrical study was performed by avidin-biotin complex method with alkaline phosphatase. RESULTS:: In chronic hepatitis C: (1) Hepatic iron accumulation was significantly increased in relation to the advance of the fibrosis. (2) Divalent metal transporter 1 decreased significantly in relation to the advance of hepatic fibrosis. (3) Transferrin receptor 1 expression was always detected, although not in normal hepatic tissues; there was no relation between expression levels and the degree of hepatic fibrosis. CONCLUSIONS:: These data demonstrated that the transferrin receptor 1 expression was up-regulated irrespective of the degree of hepatic iron accumulation, suggesting that the up-regulation of transferrin receptor 1 might act as one of the key mechanisms implicated in the accumulation of hepatic iron in chronic hepatitis C. 相似文献
43.
Expression of GPIV and Naka antigen on monocytes in Naka -negative subjects whose platelets lack GPIV
Hironori Take Hirokazu Kashiwagi Yoshiaki Tomiyama Shigenori Honda Yumiko Honda Hajime Mizutani Takayasu Furubayashi Takahiro Karasuno Tetsuo Nishiura Yoshio Kanayama Yoshiyuki Kurata Yuji Matsuzawa 《British journal of haematology》1993,84(3):387-391
Summary. The platelet antigen Naka was once considered to be a platelet-specific alloantigen and is carried on platelet membrane glycoprotein (GP) IV. Recent studies suggest that Naka -negative subjects lack platelet GPIV. GPIV is an important adhesive receptor and expressed on the surface of monocytes as well as of platelets. In the present study, flow cytometry was used to detect GPIV and Naka antigen on the surface of monocytes. Naka antigen was expressed on monocytes as well as on platelets in Naka -positive subjects ( n = 6) (P-GPIV-positive subjects). To our surprise, monocytes of Naka -negative subjects ( n = 7) (P-GPIV-negative subjects) having no anti-Naka antibody in their serum expressed GPIV and Naka antigen to almost the same degree as did the monocytes of P-GPIV-positive subjects. Competitive experiments using OKM5 (a monoclonal antibody against GPIV) and anti-Naka antibody showed that the epitope of anti-Naka antibody on monocytes was very close to that of OKM5. In two P-GPIV-negative subjects having anti-Naka antibody in their serum, GPIV and Naka antigen were not expressed on the surface of either monocytes or platelets. These results indicate that the GPIV molecules and Naka antigen are expressed on the surface of monocytes in the majority of P-GPIV-negative subjects, but that in a very few P-GPIV-negative subjects neither GPIV nor Naka antigen is expressed on the surface of their monocytes. We hypothesize that P-GPIV-negative subjects who carry neither GPIV nor Naka antigen on their monocytes produce anti-Naka antibody as a result of transfusion or pregnancy. 相似文献
44.
45.
Shinobu Osanai Toru Takahashi Hiroyuki Enomoto Nobuyuki Satoh Osamu Yahara Yuji Akiba Satoru Fujiuchi Hitoshi Nakano Yoshinobu Ohsaki and Kenjiro Kikuchi 《Respirology (Carlton, Vic.)》2001,6(2):163-166
We describe a case of a 21-year-old man with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) who presented with hypoxic ventilatory depression. He had chronic hypoventilation, which was not explained by weakness of respiratory muscles. His hypercapnic ventilatory response was not impaired. In contrast, hypoxic ventilatory depression was observed in the isocapnic progressive hypoxic response test. After exposure to hypoxic conditions, his respiratory frequency decreased and tidal volume was unchanged. The hypoxic ventilatory depression was partially blocked by pretreatment with aminophylline. In conclusion, we need to be careful with patients with MELAS who are hypoxaemic because a vicious circle of hypoxia and hypoventilation can occur. 相似文献
46.
Keiji Yamamoto Uichi Ikeda Yoko Ikeda Yoshitane Seino Tetsuo Takayasu Shin-Ichi Ooki Tsutomu Yamaguchi Kanae Fukushima Tsuguo Hasegawa Naohiro Shinohara Kazuyuki Shimada 《Heart and vessels》1993,8(3):166-169
Summary While mural thrombus accompanied by an abdominal aortic aneurysm (AAA) is not rare, the growth rate of such a thrombus has not yet been adequately documented. We present here a very rare case of a 62-year-old female patient with an AAA in whom the mural thrombus in the aneurysm grew very rapidly over a short period. We could follow the growth of the mural thrombus in the AAA by two-dimensional (2-D) abdominal echography. Patients with an AAA must be closely monitored by this technique which is able to detect the presence of the thrombus and allow evaluation of its growth. 相似文献
47.
48.
Akira Endo Hirotaka Koizumi Makiko Takahashi Tomohiro Tamura Shinobu Tatsunami Yoshiyuki Watanabe Masayuki Takagi 《Virchows Archiv : an international journal of pathology》2013,462(2):131-139
Sessile serrated adenoma/polyps (SSA/Ps) of the colon are thought to be precursors of sporadic carcinomas. Although it is suggested that SSA/P may grow rapidly from the early stage, its cell kinetics remains obscure. To solve this problem, we analyzed the mitotic and apoptotic activity of normal crypts, microvesicular hyperplastic polyps (MVHPs), and tubular adenomas (TAs), using phospho-histone H3 and cleaved caspase 3 immunohistochemistry. The mitotic index for SSA/Ps (mean, 5.63) and TAs (6.98) was significantly higher than those for normal crypts (2.72) and MVHPs (2.86). Of all tested lesions, the apoptotic index was lowest for SSA/Ps (0.96; normal, 2.71; MVHPs, 2.62; TAs, 6.01) with statistically significant differences. The net growth ratio was close to 1.0 in normal crypts (1.07) while remaining low in MVHPs (1.06) and TAs (1.38), but was markedly elevated in SSA/Ps (7.32, P?<?0.01) due to the large imbalance between mitosis and apoptosis. As to apoptosis regulatory proteins, expression of anti-apoptotic Bcl-2 was significantly reduced or undetectable in MVHPs and SSA/Ps, while TAs showed stronger staining than normal crypts. Expression of pro-apoptotic Bax and its activators, Bim and Bad, was significantly reduced in MVHPs and SSA/Ps. We suggest that other complex mechanisms may act synergistically with Bax, Bim, or Bad deficiency to regulate apoptosis suppression in SSA/Ps. 相似文献
49.
Norzila Kusnin Nor Azah Yusof Jaafar Abdullah Suriana Sabri Faruq Mohammad Shuhaimi Mustafa Nurul Asyikeen Ab Mutalib Shinobu Sato Shigeori Takenaka Nor Azizah Parmin Hamad A. Al-Lohedan 《RSC advances》2020,10(46):27336
In this study, an electrochemical DNA biosensor was developed based on the fabrication of silicon nanowires/platinum nanoparticles (SiNWs/PtNPs) on a screen-printed carbon electrode (SPCE) for the detection of Sus scrofa mitochondrial DNA (mtDNA) in food utilizing a new hybrid indicator, ferrocenylnaphthalene diimide (FND). The morphology and elemental composition of the SiNWs/PtNPs-modified SPCE was analyzed by field emission scanning electron microscopy (FESEM) combined with energy dispersive X-ray spectroscopy (EDX). Cyclic voltammetry (CV) was used to study the electrical contact between the PtNPs and the screen-printed working electrode through SiNWs, while electrochemical impedance spectroscopy (EIS) was used to measure the charge transfer resistance of the modified electrode. The results clearly showed that the SiNWs/PtNPs were successfully coated onto the electrode and the effective surface area for the SiNWs/PtNPs-modified SPCE was increased 16.8 times as compared with that of the bare SPCE. Differential pulse voltammetry used for the detection of porcine DNA with FND as an intercalator confirmed its specific binding to the double-stranded DNA (dsDNA) sequences. The developed biosensor showed a selective response towards complementary target DNA and was able to distinguish non-complementary and mismatched DNA oligonucleotides. The SiNWs/PtNPs-modified SPCE that was fortified with DNA hybridization demonstrated good linearity in the range of 3 × 10−9 M to 3 × 10−5 M (R2 = 0.96) with a detection limit of 2.4 × 10−9 M. A cross-reactivity study against various types of meat and processed food showed good reliability for porcine samples.An electrochemical DNA biosensor was developed based on the fabrication of silicon nanowires/platinum nanoparticles on a screen-printed carbon electrode for the detection of Sus scrofa mitochondrial DNA in food. 相似文献