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111.
Polyelectrolyte complexes (PEC) were prepared from chitosan as the polycation and several synthesized functional anion polysaccharides, and their effects on cell attachment, morphology, proliferation and differentiation were estimated using normal human osteoblasts (NHOst). After a 1-week incubation, PEC made from polysaccharides having carboxyl groups as polyanions showed low viability of NHOst on it although the NHOst on it showed an enhancement in their differentiation level. On the other hand, NHOst on PEC made from sulfated or phosphated polysaccharides showed similar attachment and morphology to those on the collagen-coated dish. When the number of NHOst was estimated after 1 week, the number on the PEC was ranged from 70% to 130% of those on the collagen-coated dish, indicating few effects of these PEC on cell proliferation. In addition, NHOst on PEC films made from sulfated polysaccharides differentiated to a level very similar to that observed on the collagen-coated dish, indicating that these PEC films maintain the normal potential of NHOst to both proliferate and differentiate. Measurement of gap junctional intercellular communication of NHOst on PEC revealed that PEC did not inhibit communication, suggesting that PEC films have few effects on cell homeostasis. Thus, PEC made from the sulfated polysaccharide may be a useful material as a new scaffold for bone regeneration. 相似文献
112.
Toru Furukawa Rumi Fujisaki Yoshitaro Yoshida Naomi Kanai Makoto Sunamura Tadayoshi Abe Kazunori Takeda Seiki Matsuno Akira Horii 《Modern pathology》2005,18(8):1034-1042
DUSP6/MKP-3 is identified as a candidate tumor suppressor gene for pancreatic cancer. The aim of this study was to elucidate the roles of DUSP6 in the pancreatic carcinogenesis through the pancreatic intraepithelial neoplasia and/or intraductal papillary-mucinous neoplasms, both of which are considered to be precursor lesions of invasive carcinoma of the pancreas, by comparing with involvements of other major tumor suppressive pathways. Expressions of DUSP6, CDKN2A, TP53, and SMAD4 were investigated by immunohistochemistry in a total of 206 lesions of dysplastic ductal precursors and carcinomas retrieved from 52 pancreata with invasive ductal carcinomas and 51 of those with intraductal papillary-mucinous neoplasms. The intensity of staining was evaluated in lesions at different atypical grades and statistically compared among them. Mutations of KRAS2 were analyzed by methods of the allele-specific oligonucleotide hybridization and nucleotide sequencing. In pancreata with invasive ductal carcinomas, expressions of DUSP6 were abrogated exclusively in the invasive carcinoma cells in contrast to its fairly preserved expressions in pancreatic intraepithelial neoplasia. In pancreata with intraductal papillary-mucinous neoplasms, abrogated expressions of DUSP6 were observed in a relatively small fraction of intraductal adenoma/borderlines and intraductal carcinomas. Most of the intraductal adenoma/borderline lesions with abrogation of DUSP6 harbored mutations of KRAS2. None of the molecules was associated with each other in any grade of lesions. Morphological variations of papillae of the intraductal papillary-mucinous neoplasms were evaluated and analyzed for their associations with abrogations of the molecules, which resulted in finding of no significant associations. Our results suggest that the abrogation of DUSP6 is associated exclusively with progression from pancreatic intraepithelial neoplasia to the invasive ductal carcinoma while it is potentially associated with initiation of intraductal papillary-mucinous neoplasms with mutated KRAS2, which is independent of other major tumor suppressive pathways in both types of neoplasms. 相似文献
113.
Tatsuo Michiue Akimasa Fukui Akira Yukita Kenji Sakurai Hiroki Danno Akira Kikuchi Makoto Asashima 《Developmental dynamics》2004,230(1):79-90
Wnt signaling pathways are involved during various stages in the development of many species. In Xenopus, the accumulation of beta-catenin on the dorsal side of embryo is required for induction of the organizer, while the head structure formation requires inhibition of Wnt signaling. Here, we report a role for xIdax, a negative regulator of Wnt signaling. XIdax is expressed in neural tissues at the neurula stage, and in the restricted region of the tadpole brain. Ectopic expression of xIdax inhibits the target gene expression, suggesting that xIdax can inhibit canonical Wnt signaling. To examine the function of xIdax, a morpholino oligo for xIdax (xIdaxMO) was designed. An injection into an animal pole cell caused a loss of forebrain. The anterior neural marker expression is decreased in xIdaxMO-injected embryo, suggesting that xIdax is required for anterior neural development. Moreover, a negative regulator that acts downstream of xIdax rescued this defect. We propose that Idax functions are dependent on the canonical Wnt pathway and are crucial for the anterior neural development. 相似文献
114.
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
115.
Akira Nakagawara Toshimitsu Toyohara Keiichi Ikeda Osami Nada Masazumi Tsuneyoshi 《Virchows Archiv : an international journal of pathology》1986,409(5):571-582
Summary The intratumorous distribution of catecholaminergic clone cells in 23 human neuroblastomas was studied using Falck-Hillarp's method, and the findings compared with the catecholamine (CA) content within the tumour. All the specimens contained elements with CA fluorescence, and the pattern of fluorescence was classified from the distribution of CA-positive cells and neurofibrils, as diffuse cellular (DC); diffuse fibrillary (DF), sporadic (S), clustered (C), island-shaped (I), and bundled (B). The strength of CA fluorescence of both cellular and fibrillary elements correlated well with the CA content within the tumour. In addition, all tumours of urinary VMA-negative cases also contained significantly larger amounts of CA than other, non-functioning, tumours in the paediatric age group. The results of this study suggest that firstly, the ratio of CA-positive cells to CA-positive neuronal processes is proportionately higher in the poorly-differentiated neuroblastomas and that secondly, even tumours negative for urinary VMA or HVA might be polyclonal and contain catecholaminergic elements.This study was supported in part by a Research Grant from the Ministry of Education, Japan (No. 59570549) 相似文献
116.
Yamamoto A Nakayama M Kurosawa Y Sugo K Karasawa H Ogawa T Takasaki T Tashiro M Kurane I 《Journal of virological methods》2002,104(2):195-201
Japanese encephalitis virus-specific IgM is a reliable indicator for serodiagnosis of Japanese encephalitis. A particle agglutination (PA) assay system was developed to detect anti-Japanese encephalitis virus IgM in human serum samples. The newly developed PA assay consisted of hydroxyapatite-coated nylon beads and V-bottom 96-well microplates. Hydroxyapatite-coated nylon beads were coated with Japanese encephalitis virus antigens. Japanese encephalitis virus antigen-coated, hydroxyapatite-coated nylon beads agglutinated in the IgM-captured wells when anti-Japanese encephalitis virus IgM-positive serum samples were used. A button pattern was formed at the bottom of the wells when anti-Japanese encephalitis virus IgM-negative serum samples were used. Thirty anti-Japanese encephalitis virus IgM-positive serum samples from Japanese encephalitis-confirmed cases were tested by the PA assay. All these serum samples were determined to be Japanese encephalitis virus IgM-positive. IgM titers determined by the PA assay corresponded to those determined by enzyme-linked immunosorbent assay. The titers were consistent in two independent PA assays. These results indicate that the newly developed PA assay is a reliable method for detecting anti-Japanese encephalitis virus IgM in human serum samples and that this assay will be a suitable diagnostic system especially in rural areas of Asia. 相似文献
117.
Yoshizawa M Sato T Tanaka A Abe K Takeda H Yambe T Nitta S Nosé Y 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(4):443-448
The present study has proposed a new method for estimating the pressure head (P(t)[mm Hg]) and flow (Q(t)[L/min]) of a centrifugal pump on the basis of voltage (V(t)[V]), current (I(t)[A]), and rotational speed (N(t)[k(rpm)]) of the DC motor for a pump without any additional sensors. In the proposed estimation method, two auto-regressive exogenous (ARX) models are employed. One ARX model has an output, P(t) or Q(t), and three inputs, VI(t) = V(t)I(t) and N(t) and the steady state gain (K) of the system from VI(t) to N(t). It can be assumed that K may include the information on viscosity of blood. The coefficient parameters of this ARX model are identified in an off-line fashion before implantation of the pump. After implantation, P(t) or Q(t) is estimated by the same ARX model with the already identified parameters. The other ARX model is used to identify Kon the basis of VI(t) and N(t) in an on-line fashion every time the viscosity of blood may change. In the experiment, a mock circulatory system consisting of a centrifugal pump and a reservoir with 37% glycerin or water was employed. The root mean square error between measured Q(t) and its estimate obtained from the proposed method was 1.66L/min. On the other hand, a different method based on a single ARX model with inputs of VI(t) and N(t), but without the additional input of K, yielded the corresponding estimation error of 2.22L/min. This means that the proposed method can reduce its estimation error by about 25% in comparison with a method that cannot cope with the change in blood viscosity. 相似文献
118.
Tadashi Narita Tokio Hagiwara Hiroshi Hamana Takehiko Miyasaka Akira Wakayama Tetsuo Hotta 《Macromolecular chemistry and physics.》1987,188(2):273-279
The anionic polymerizations of 2,2,2-trifluoroethyl acrylate ( 1a ), 2,2,2-trifluoroethyl methacrylate ( 1b ), 2,2,2-trifluoro-1-trifluoromethylethyl acrylate ( 2a ), and 2,2,2-trifluoro-1-trifluoromethylethyl methacrylate ( 2b ) were examined with triethylaluminium and diethylaluminium active methylene chelate compounds as initiators. 2b was polymerized with triethylaluminium. Diethyl(ethyl cyanoacetato)aluminium was found to produce polymers of 1a and 1b . Diethyl(acetylacetonato)aluminium and diethyl (dimethyl malonato)aluminium, however, show low reactivity towards these four monomers. The resulting polymers show unimodal molecular weight distribution with number-average molecular weights of 104?105, measured by GPC. The initiation reaction and the copolymerization reactivity with styrene support the anionic polymerization mechanism. 相似文献
119.
Junko Watanabe Masami Taniguchi Kiyoshi Takahashi Takemasa Nakagawa Yukihiro Ooya Akira Akazawa Kazuo Akiyama 《Arerugī》2006,55(11):1421-1428
PURPOSE: To enable international comparison of prevalence in asthma, we translated and evaluated ECRHS Questionnaire, which is introduced in GINA. Considering COPD prevalence in elder people, we added two questions to the ECRHS Questionnaire. METHOD: The Japanese edition of ECRHS Questionnaire was responded by 366 patients who were diagnosed asthma without COPD, 61 patients who were diagnosed COPD without asthma, and 137 healthy persons who were not diagnosed asthma or COPD. We analyzed the answers of the each group and evaluated the validity of the questionnaire to use for the nation-wide prevalence study of adult asthma in future. RESULTS: The question of 'Wheezing at any time in the last 12 months' had the highest Youden's index and validity to pick up asthma patients. The questions of 'Waking up with a feeling of tightness in chest at any time in the last 12 months' and 'Waking up by an attack of shortness of breath at any time in the last 12 month' had the highest specificity to pick up asthma patients. Most of the questions which were related asthma were able to be answered by asthma patients properly, but some questions were improperly answered by patients and healthy persons in elderly. The results in this study showed the less recognition of their diseases in elderly patients than younger patients and the limitation of the study with written questionnaire for elderly people. Not a few COPD patients complained wheezing or whistling in the chests as same as asthma patients in this study. CONCLUSION: We concluded that we had almost enough reliability in the Japanese edition of the ECRHS questionnaire for screening survey of asthma prevalence in Japan. 相似文献
120.
Kazushige Dobashi Kohtaro Asayama Hidemasa Hayashibe Afreen Munim Akira Kawaoi Masahiko Morikawa Shinpei Nakazawa 《Virchows Archiv : an international journal of pathology》1993,423(3):177-184
To determine the late gestational development of copper-zinc (CnZn) and manganese (Mn) superoxide dismutases (SOD) in human lung, immunohistochemical localization was performed for each SOD. The lung samples were taken from five aborted fetuses, four fetuses in which intrauterine death occurred, one full-term neonate, two premature infants with hyaline membrane disease and one premature infant with bronchopulmonary dysplasia (BPD). Morphometry was performed, and the percent area of positive staining was computed. The bronchial epithelium was intensely stained from the early stages of gestation (i.e. 17 weeks), while the staining intensity for both CuZnSOD and MnSOD in the peripheral airways increased gradually during lung development. The mean percent area of the staining for CuZnSOD and MnSOD from 16 to 38 weeks was increased 30-fold and 8-fold, respectively, and further increases were observed postnatally. CuZnSOD staining was markedly decreased in lungs with respiratory disorders. However, proliferating type II pneumocytes were intensely stained for MnSOD in the BPD lungs, making the staining area 3-fold larger than that in the control lungs. These results clearly depict age-related increases in staining for both CuZnSOD and MnSOD and an alteration in SOD distribution associated with neonatal respiratory disorders. 相似文献