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41.
Okamoto T Hashimoto M Samejima H Mori A Wakabayashi M Takeda A Nakamura H Naruse H Bouike Y Araki N 《Immunopharmacology and immunotoxicology》2004,26(4):645-652
Immediate hemolytic transfusion reactions (IHTR) occurred in the course of delayed hemolytic transfusion reactions (DHTR). An 84-year-old man had received a blood transfusion 20 years ago. Progressive anemia developed, because of continuous bleeding from a bladder tumor. He was transfused with concentrated red blood cells (CRC) which were Rh-E antigen negative, because he had anti-E antibodies (day 0). He received CRC on day 3, and underwent resection of bladder tumor on day 6. Although crossmatch-compatible CRCs were prepared for the operation, those were not required and were kept in a refrigerator in the ward. On day 9, when a CRC kept in the ward was transfused, he suddenly had a IHTR. In order to analyze a mechanism of IHTR, the anti-Jk(b) and anti-Di(b) antibodies, anti-HLA antibodies and the concentrations of inflammatory cytokines were measured in serum samples. The anti-Jk(b) and anti-Di(b) antibodies increased prior to IHTR experienced on day 9. The concentrations of IL-6 and IL-1beta increased from day 2, while the concentration of IL-8 increased from day 7. The anti-HLA class I antibody could be detected 2 days before IHTR. Thus, the anti-Jk(b) and anti-Di(b) antibodies induced the production of inflammatory cytokines and symptoms of DHTR and IHTR. The anti-HLA class I antibody could be produced in spite of using the filer for removing leukocytes, and may take part in the induction of IHTR. Further, blood products should be transfused soon after completing a crossmatch test in patients with anti-RBC alloantibodies. 相似文献
42.
Budipitojo T Sasaki M Matsuzaki S Cruzana MB Iwanaga T Kitamura N Yamada J 《Archives of histology and cytology》2003,66(4):337-346
Gastrin-releasing peptide (GRP) has been proposed as a novel regulatory peptide in the reproductive tract. We previously demonstrated that GRP immunoreactivities are found predominantly in the uterine gland epithelial cells of nonpregnant and pregnant cows. The present study focused on the distribution of GRP immunoreactivity and the expression of GRP mRNA in the bovine endometrium during the estrous cycle. Tissues were collected from 21 uterine horns and bodies during the estrous cycle. RT-PCR showed the expected GRP mRNA fragments (284 bp) in the tissues from all stages of the cycle. In situ hybridization results ascertained the expression of the GRP mRNA in the uterine gland epithelial cells and superficial epithelial cells of the endometrium. Positive staining of GRP immunoreactivity in the uterine gland epithelial cells was detected in both the uterine horn and body from all stages of the cycle. In metestrus and diestrus stages, GRP was also detected in the superficial epithelial cells of horn, but not in the body. The degrees of GRP mRNA expression and intensities of GRP immunoreactivity in the endometrium increased from proestrus to diestrus stages. These findings suggest that GRP may be important both in the endometrial remodeling during the estrous cycle and in the implantation and development of blastocysts. 相似文献
43.
Nobuo Donkai Hiroshi Inagaki Kanji Kajiwara Hiroshi Urakawa Manfred Schmidt 《Macromolecular chemistry and physics.》1985,186(12):2623-2638
Imogolite, a natural product in the clay fraction of Japanese soil, was characterized through its dilute solution properties. Various methods were employed for this characterization, including viscosity, sedimentation, static/dynamic light scattering, and small angle X-ray scattering. All these measurements have revealed consistently that imogolite is represented by a rigid thin rod within the accuracy of available theories, where its repeat unit is composed of twelve gibbsite units. Since the evaluation of the chain length from the observed quantities depends on the molecular weight distribution, its effect was also considered where Mw/Mn ≈ 1,2 was estimated from the sedimentation profile. 相似文献
44.
Kanji Kajiwara Nobuo Donkai Yuzuru Hiragi Hiroshi Inagaki 《Macromolecular chemistry and physics.》1986,187(12):2883-2893
The acidic aqueous solution of imogolite is proposed to be an ideal lyotropic system. No temperature dependence was marked on the two phase boundary concentrations (A and B points) of imogolite solutions as predicted by the theories of Flory and Onsager. A satisfactory quantitative agreement was observed with Onsager's theory. The polydispersity of rod lengths was found to shift the A point towards lower concentrations than expected from theory. 相似文献
45.
The effect of bile duct ligation on enzyme activities in the subfractions of the rat liver plasma membrane was investigated. Two subfractions were isolated from the rat liver plasma membrane by homogenization and subsequent centrifugation in a discontinuous sucrose gradient. The light subfraction contained fragments of the bile canalicular surface and the heavy fraction contained fragments of the sinusoidal and lateral surfaces of the hepatocyte. Bile duct ligation decreased NaK ATPase and Mg-ATPase activity in the light subfraction, whereas it had no significant effect on these enzyme activities in the heavy fraction. Leucyl-β-naphthylamidase activity was reduced and alkaline phosphatase activity was increased in both subfractions. These facts suggested that ligation of the bile duct led to loss of the secretory polarity of the liver cell. The in vitro effects of some bile acids on the membranebound enzymes in the light subfraction were investigated, and a possible involvement of chenodeoxycholic acid in the alteration of enzyme activities in the bile canalicular membrane was suggested. 相似文献
46.
Keiichi Tamai Masafumi Toyoshima Nobuyuki Tanaka Noriko Yamamoto Yuji Owada Hiroshi Kiyonari Kazuko Murata Yoshiyuki Ueno Masao Ono Tooru Shimosegawa Nobuo Yaegashi Masahiko Watanabe Kazuo Sugamura 《The American journal of pathology》2008,173(6):1806-1817
The endosomal sorting complex required for transport (ESCRT) proteins form multimolecular complexes that control multivesicular body formation, endosomal sorting, and transport ubiquitinated membrane proteins (including cell-surface receptors) to the endosomes for degradation. There is accumulating evidence that endosomal dysfunction is linked to neural cell degeneration in vitro, but little is known about the relationship between neural disorders and ESCRT proteins in vivo. Here we specifically deleted the hrs gene, ESCRT-0, in the neurons of mice by crossing loxP-flanked hrs mice with transgenic mice expressing the synapsin-I Cre protein (SynI-cre). Histological analyses revealed that both apoptosis and a loss of hippocampal CA3 pyramidal neurons occurred in the hrsflox/flox;SynI-cre mice. Notably, the hrsflox/flox;SynI-cre mice accumulated ubiquitinated proteins, such as glutamate receptors and an autophagy-regulating protein, p62. These molecules are particularly prominent in the hippocampal CA3 neurons and cerebral cortex with advancing age. Accordingly, we found that both locomotor activity and learning ability were severely reduced in the hrsflox/flox;SynI-cre mice. These data suggest that Hrs plays an important role in neural cell survival in vivo and provide an animal model for neurodegenerative diseases that are known to be commonly affected by the generation of proteinaceous aggregates. 相似文献
47.
Expression of cyclin D1, retinoblastoma gene protein, and p16 MTS1 protein in atypical adenomatous hyperplasia and adenocarcinoma of the lung 总被引:2,自引:0,他引:2
Y. Kurasono Takaaki Ito Yoichi Kameda Nobuo Nakamura Hitoshi Kitamura 《Virchows Archiv : an international journal of pathology》1998,432(3):207-215
To clarify the events leading to the disruption of cell growth control that occurs during the development of pulmonary adenocarcinoma
(AC), we used immunohistochemistry to evaluate the expression of G1 cycle regulators, cyclin D1, Rb protein (pRb), and p16
MTS1 protein and the tumour proliferation marker, Ki 67, both in AC of the lung and in its precursor lesion, atypical adenomatous
hyperplasia (AAH). The frequency of lesions with cyclin D1 overexpression was relatively high in AAH (47–89%), but was decreased
in early AC (28%) and overt AC (35%). The loss of pRb expression was rare in both AAH (0–18%) and early AC (0%), and was infrequent
even in overt AC (13%). The loss of p16 expression was also relatively infrequent in both the premalignant and the malignant
lesions (11–25%). Our results suggest that overexpression of cyclin D1 is an early event and plays an important part in tumorigenesis
in the case of lung AC. However, cyclin D1 overexpression is not required for the development and maintenance of a malignant
phenotype. It is likely that some cyclin D1-independent pathways other than Rb and p16 abnormalities have an important role
in the malignant transformation from AAH to early AC.
Received: 8 July 1997 / 26 September 1997 相似文献
48.
Yasuhiko?IwasakiEmail author Nobuo?Nakabayashi Kazuhiko?Ishihara 《Journal of artificial organs》2003,6(4):260-266
To identify the advantages of 2-methacryloyloxyethyl phosphorylcholine (MPC) copolymer-coated polysulfone (PSf) hollow fibers for hemodialyzer and hemofilter minimodules with hollow fibers were made and blood compatibility was evaluated in vitro and ex vivo. Three types of hollow fibers, i.e., pure PSf (no additives), PSf alloyed with poly(1-vinyl-2-pyrrolidone) (PVPy), and PSf coated with the MPC copolymer, were processed in wet conditions. Commercially available hollow fibers (APS) were used as a control sample. The PSf hollow fibers have a condensed structure. A porous structure was observed when the PVPy was alloyed before wet processing, and no effect of the innercoated MPC copolymer on the porous structure was observed. One-tenth-sized minimodules of the conventional hemodialyzer were fabricated with 200 fibers each. The solute permeability of the hollow fibers was evaluated using 10% bovine serum in a buffer solution containing cytochrome C, which is a model protein of 2-microglobulin. After circulation for 2.5h, the solute permeability of APS and PVPy-alloyed PSf hollow fibers decreased to 50% compared with their initial values. In contrast, the value for the hollow fibers innercoated with the MPC copolymer maintained its initial level. The inner surface of the dialysis membranes was observed with a transmission electron microscope and a layer of adsorbed protein on the PSf, APS, and PVPy-alloyed PSf hollow fibers was observed, but not on the MPC copolymer-coated fibers. Blood cell adhesion was then evaluated by circulation of whole rabbit blood without any anticoagulant ex vivo. Many adherent cells were observed on the PVPy-alloyed PSf hollow fibers; however, blood cells did not adhere or aggregate on the MPC copolymer-coated hollow fibers. From these results, we concluded that the in-situ coating of MPC copolymer on PSf hollow fibers is effective in preventing blood coagulation and maintaining the solute permeability of the fibers. 相似文献
49.
Haruo Hagiwara Nobuo Ohwada Takeo Aoki Takeshi Suzuki Kuniaki Takata 《Medical molecular morphology》2008,41(4):221-226
Stromal cells in the lamina propria of the human oviduct mucosa are unique cells that can differentiate into decidual cells
during ectopic pregnancy in the oviduct. The nature of stromal cells is still unknown. In the present study, we investigated
human oviductal stromal cells with transmission electron microscopy and immunohistochemistry and revealed that they had ultrastructural
features similar to myofibroblasts and expressed alpha-smooth muscle actin, a marker used to identify myofibroblasts. Primary
cilia were also one of the characteristic profiles of the stromal cells. These findings showed that the connective tissue-stromal
cells in the human oviduct mucosa are myofibroblasts. They are considered to play an important role in the transport of oocytes
by bringing about contraction of the mucosal folds. 相似文献
50.
Nobuo Takeshima Kiyoji Tanaka Fumio Kobayashi Takemasa Watanabe Takashi Kato 《European journal of applied physiology》1993,67(2):138-143
Summary In this study we attempted to determine the effects of exercise training at the intensity corresponding to lactate threshold (Thla
–) on various health-related variables in sedentary but apparently healthy elderly subjects. Six men and five women volunteers [mean age 68.9 (SD 3.4) years] performed supervised endurance-type training on stationary cycle ergometers for 30 min and recreational activities for 30 min, 3 days a week for 12 weeks. Four men and four women served as the control group [68.8 (SD 4.4) years]. As a result of the training programme, statistically significant increases in maximal oxygen consumption (10%), oxygen consumption at Thla
–(18%), distance covered in 12-min walk, side step, and leg extensor power were found in the training group, while no changes occurred in the control group. The changes in serum cholesterol and triglyceride concentrations from the pre- to post-training period were statistically significant. High-density lipoprotein cholesterol remained unchanged, and low-density lipoprotein cholesterol tended to decrease following the training programme. These data would indicate that exercise training at the intensity corresponding to Thla
–may have favourable effects on overall physical fitness and some serum lipid variables in older individuals. 相似文献