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971.
972.
Takemoto Y Hozumi T Sugioka K Watanabe H Matsumura Y Yoshiyama M Takeuchi K Yoshikawa J 《Echocardiography (Mount Kisco, N.Y.)》2006,23(8):658-665
BACKGROUND: A newly developed automated mitral annular tracking method (AMAT) has recently become available and enables us to perform automated analysis of mitral annular dynamics. PURPOSE: To evaluate mitral annular dynamics using AMAT. METHODS: AMAT was performed using a Toshiba Aplio SSA-770 ultrasound system in 15 normal healthy volunteers (group N), 16 patients with anterior MI (group A), and 12 inferior MI (group B). The distance between an annular point at end-diastole and at end-systole (distance D) was automatically measured using AMAT at the basal portion of the anterior, lateral, posterior, inferior, and inferoseptal wall. The angle between the mitral annular plane at end-diastole and the direction of movement of each mitral annular point from end-diastole to end-systole (angle A) was also automatically measured at all five mitral annular points. The coefficients of variation (CV) of both distance D and of angle A were calculated as indices of asynchrony of mitral annular dynamics. RESULTS: CV of distance D in group A (22 +/- 9% (P < 0.01 vs group N)) and group B (22 +/- 10% (P < 0.01 vs group N)) were both significantly larger than in group N (13 +/- 4%). CV of angle A in group A (15 +/- 10% (P < 0.05 vs group N)) and group B (15 +/- 10% (P < 0.05 vs group N)) were also significantly larger than that in group N (8 +/- 3%). CONCLUSION: Automated analysis using AMAT showed that mitral annular dynamics of patients with MI were less symmetrical than in normal healthy volunteers. 相似文献
973.
Seiji Yano Yasuhiko Nishioka Keisuke Izumi Takashi Tsuruo Toshiyuki Tanaka Masayuki Miyasaka Saburo Sone 《International journal of cancer. Journal international du cancer》1996,67(2):211-217
Metastasis is a critical problem in the treatment of human lung cancer. Thus, a suitable animal model of metastasis of human lung cancer is required for in vivo biological and preclinical studies. In this study, we tried to establish a suitable model for this, using SCID mice. Neither human SCLC H69/VP cells (5 × 106) nor squamous-cell carcinoma RERF-LC-AI cells (1 × 106), injected through a tail vein, formed metastases in untreated SCID mice. Pre-treatment of SCID mice with anti-asialo GM1 serum resulted in only a few metastases of H69/VP cells, but pre-treatment with anti-mouse IL-2 receptor β chain Ab (TM-β1) resulted in numerous lymph-node metastases 56 days after tumor inoculation. H69/VP-M cells, an in vivo-selected variant line, formed significant numbers of lymph-node metastases even in SCID mice pre-treated with anti-asialo GM1 serum. SCID mice depleted of NK cells by treatment with TM-β1 showed different patterns of metastasis when inoculated intravenously with the 2 different human lung cancer cell lines (H69/VP and RERF-LC-AI cells): H69/VP cells formed metastases mainly in systemic lymph nodes and the liver, whereas RERF-LC-AI cells formed metastases mainly in the liver and kidneys, with only a few in lymph nodes. A histopathological study showed that the metastatic colonies consisted of cancer cells. The numbers of metastatic colonies formed by the 2 cell lines increased with the number of cells inoculated. TM-β1 treatment of SCID mice efficiently removed NK cells from peripheral blood for at least 6 weeks, whereas, after treatment of the mice with anti-asialo GM1 serum, NK cells were recovered within 9 days. These findings suggest that NK-cell-depleted SCID mice may be useful as a model in biological and pre-clinical studies on metastasis of human lung cancer. © 1996 Wiley-Liss, Inc. 相似文献
974.
Small guanosine triphospatase RhoA and Rho-associated kinase as regulators of trophoblast migration 总被引:6,自引:0,他引:6
Shiokawa S Iwashita M Akimoto Y Nagamatsu S Sakai K Hanashi H Kabir-Salmani M Nakamura Y Uehata M Yoshimura Y 《The Journal of clinical endocrinology and metabolism》2002,87(12):5808-5816
The small guanosine triphosphatase Rho controls cell adhesion and motility through reorganization of the actin cyto-skeleton and regulation of actomyosin contractility. Among the putative target molecules of Rho, a Rho-associated coiled coil-forming protein kinase (ROCK) is thought to participate in Rho-mediated cell adhesion and motility. In the present study, we explored the expression and function of RhoA and ROCK in human trophoblast cells. The colocalization of RhoA, cytokeratin 8/18, and cytokeratin 7 in some cells located in the decidual stromal region indicated that extravillous trophoblast cells expressed RhoA. In double staining for RhoA and ROCK in human chorionic villi, RhoA staining was strongly positive in the cytoplasm of cytotrophoblasts, whereas ROCK stained in the cytoplasm of cytotrophoblasts and syncytiotrophoblasts. Both RhoA and ROCK were stained in cytoplasma of cultured human cytotrophoblast. Cultured human trophoblast cells contained actin stress fibers that were lost after treatment with C3, an exoenzyme produced by Clostridium botulinum. Y-27632, a selective ROCK inhibitor, suppressed RhoA-induced formation of actin stress fibers and formation of focal contact in trophoblast cells. The trophoblast reacquired actin stress fibers and focal contact after withdrawal of Y-27632. Cultured human cytotrophoblast cells from 7-9 wk of gestation migrated into a fibronectin-coated membrane. Both C3 exoenzyme and Y-27632 inhibited cytotrophoblast migration in a dose-dependent manner. In conclusion, cyto-trophoblasts express RhoA and ROCK in their cytoplasm, and RhoA-ROCK is involved in their assembly of actin stress fibers. Suppression of RhoA-ROCK reduces trophoblast migration. These findings suggest that RhoA-ROCK signaling is a key regulator of trophoblast cell migration. 相似文献
975.
Shigeyuki Kuratsu Akira Myoui Yasuhiko Tomita Norifumi Naka Atsumasa Uchida Keiro Ono Katsuyuki Aozasa 《Journal of surgical oncology》1993,54(3):139-145
Accurate histologic grading is essential for making a proper therapy decision in soft-tissue sarcomas (STS). The usefulness of the argyrophilic stain for nucleolar organizer region (AgNOR) in assessing the histologic grade of STS has been examined. One hundred and forty-two patients with STS confined to the extremity and trunk were selected. Tumors were classified based on the criteria of Enzinger and Weiss [“Soft-Tissue Tumors.” St. Louis: C.V. Mosby, 1983]. In addition, non-specific classification was made based on the shape of proliferating cells occupying more than 50% of the field in the sections such as pleomorphic cell, small round cell, spindle cell, epithelioid cell, myxoid, and unclassified tumors. The mean number of AgNOR dots per nucleus of tumor cells was calculated in 200 cells (AgNOR count). Each category of non-specific classification was divided into a high-count group (<8 AgNOR count) and a low-count group (>8 NOR). The low-count group showed a significantly better prognosis than the high-count group in small round cell and spindle cell tumors (P< 0.007 and P< 0.0005, respectively). Similar results were obtained in pleomorphic cell tumors, though they were statistically not significant because of the relatively small number of examined cases. Most patients with epithelioid cell and myxoid tumors were in the low-count group. These findings suggest that the assessment of histologic grading of STS could be made effectively by the non-specific classification and the aid of AgNOR Staining. © 1993 Wiley-Liss, Inc. 相似文献
976.
Sugiura-Ogasawara M Ozaki Y Nakanishi T Kumamoto Y Suzumori K 《American journal of reproductive immunology (New York, N.Y. : 1989)》2005,53(1):50-53
PROBLEM: It is unclear whether chlamydia infection influences the miscarriage rate and immunological factors in patients with recurrent miscarriage. METHOD OF STUDY: Chlamydia DNA, IgA and IgG to Chlamydia trachomatis, natural killer cell activity, complement 3 (C3), C4, hemolytic complement, antinuclear antibodies, antiphospholipid antibodies, prolactin, activated partial thromboplastin time, prothrombin time and fibrinogen were examined in 504 patients with a history of two or more consecutive first-trimester miscarriages. Subsequent pregnancy outcomes were compared between cases with and without antibodies to C. trachomatis. RESULTS: Totals of 10 of 30 and 48 of 201 patients receiving no medication miscarried subsequently with and without chlamydia infection. Chlamydia IgA and/or IgG were associated with a high level of C3 but not other immunological and coagulatory parameters. CONCLUSION: Antibodies to C. trachomatis do not influence subsequent pregnancy outcome in patients with a history of recurrent miscarriage. 相似文献
977.
Ohta S Nitta N Sonoda A Seko A Tanaka T Takahashi M Takemura S Tabata Y Murata K 《European journal of radiology》2009,72(3):534-540
Purpose
To confirm prolonged cisplatin release from drug-loaded gelatin microspheres (GMSs) and their improved chemoembolic anti-cancer effect against VX2 liver tumors in rabbits.Materials and methods
Two groups of twelve rabbits each were treated intraarterially either with 2 mg/kg cisplatin-loaded GMSs (=0.04 mg/kg cisplatin) or 0.04 mg/kg cisplatin solution by administering them into the right renal artery. Platinum concentrations within the renal parenchyma were analyzed immediately following infusion (day 0) and on days 1, 3, and 7 using the atomic absorption method. In a second experiment four groups of five rabbits each with implanted VX2 liver tumors were treated intraarterially through the hepatic artery with the following drugs: 2 mg/kg cisplatin-loaded GMSs (=0.04 mg/kg cisplatin) (group I), 2 mg/kg GMSs without any drug (group II), 1.5 mg/kg cisplatin solution (group III) and saline (group IV). Tumor volumes were analyzed pre-injection and 7 days after with MRI allowing calculating the relative tumor growth rate (%). Degree of liver cell necrosis was assessed on the histopathological specimens.Results
The renal parenchymal platinum concentrations (μg/ml) with 4.51 ± 2.25 (day 0), 1.59 ± 0.70 (day 1), 0.72 ± 0.10 (day 3) and 0.20 ± 0.06 (day 7) were significantly more pronounced after cisplatin-loaded GMS on days one and three compared to cisplatin with 1.99 ± 0.55, 0.08 ± 0.03, 0.18 ± 0.01 and 0.10 ± 0.07, respectively. Relative tumor growth rates resulted in 84.5% ± 26.4 (group I); 241.4% ± 145.1 (II); 331.9% ± 72.2 (III), and 413.6% ± 103.6 (IV) with statistical significant differences between groups I and III, and groups I and IV. Similar degrees of necrosis were observed in both GMSs treated groups, while ballooning of hepatocytes was highest in cisplatin-loaded GMSs.Conclusions
With cisplatin-loaded GMSs more pronounced and prolonged local parenchymal cisplatin concentrations may be achieved offering the advantage of an increased and prolonged anti-cancer effect compared to cisplatin alone or controls. Moreover this proves indirectly the breakdown and release of cisplatin from the GMSs which is of primary importance for drug delivery systems. 相似文献978.
Yasuo Inoue Ichio Aoki Yuki Mori Yuko Kawai Toshihiko Ebisu Yasuhiko Osaka Takashi Houri Katsuyoshi Mineura Toshihiro Higuchi Chuzo Tanaka 《NMR in biomedicine》2010,23(3):304-312
Immediate and certain determination of the treatable area is important for choosing risky treatments such as thrombolysis for brain ischemia, especially in the super‐acute phase. Although it has been suggested that the mismatch between regions displaying ‘large abnormal perfusion’ and ‘small abnormal diffusion’ indicates a treatable area on an MRI, it has also been reported that the mismatch region is an imperfect approximation of the treatable region named the ‘penumbra’. Manganese accumulation reflecting calcium influx into cells was reported previously in a middle cerebral artery occlusion (MCAO) model using activity‐induced manganese‐enhanced (AIM) MRI. However, in the super‐acute phase, there have been no reports about mismatches between areas showing changes to the apparent diffusion coefficient (ADC) and regions that are enhanced in AIM MRI. It is expected that the AIM signal can be enhanced immediately after cerebral ischemia in the necrotic core region due to calcium influx. In this study, a remote embolic rat model, created using titanium‐oxide macrospheres, was used to observe necrotic neural responses in the super‐acute phase after ischemia. In addition, images were evaluated by comparison between ADC, AIM MRI, and histology. The signal enhancement in AIM MRI was detected at 2 min after the cerebral infarction using a remote embolic method. The enhanced area on the AIM MRI was significantly smaller than that on the ADC map. The tissue degeneration highlighted by histological analysis corresponded more closely to the enhanced area on the AIM MRI than that on the ADC map. Thus, the manganese‐enhanced region in brain ischemia might indicate ‘necrotic’ irreversible tissue that underwent calcium influx. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
979.
980.
Tiffany N. Vo Yasuhiko Tabata 《Journal of biomaterials science. Polymer edition》2016,27(12):1277-1290
This work investigated the effects of cellular encapsulation density and differentiation stage on the osteogenic capacity of injectable, dual physically and chemically gelling hydrogels comprised of thermogelling macromers and polyamidoamine crosslinkers. Undifferentiated and osteogenically predifferentiated mesenchymal stem cells (MSCs) were encapsulated within 20 wt% composite hydrogels with gelatin microparticles at densities of six or 15 million cells/mL. We hypothesized that a high encapsulation density and predifferentiation would promote increased cellular interaction and accelerate osteogenesis, leading to enhanced osteogenic potential in vitro. Hydrogels were able to maintain the viability of the encapsulated cells over a period of 28 days, with the high encapsulation density and predifferentiation group possessing the highest DNA content at all time points. Early alkaline phosphatase activity and mineralization were promoted by encapsulation density, whereas this effect by predifferentiation was only observed in the low seeding density groups. Both parameters only demonstrated short-lived effects when examined independently, but jointly led to greater levels of alkaline phosphatase activity and mineralization. The combined effects suggest that there may be optimal encapsulation densities and differentiation periods that need to be investigated to improve MSCs for biomaterial-based therapeutics in bone tissue engineering. 相似文献