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81.
A new pseudo-peptide of Arg-Gly-Asp (RGD) with inhibitory effect on tumor metastasis and enzymatic degradation of extracellular matrix 总被引:2,自引:0,他引:2
Hideki Fujii Naoyuki Nishikawa Hiroyuki Komazawa Makoto Suzuki Masayoshi Kojima Isamu Itoh Aya Obata Koichi Ayukawa Ichiro Azuma Ikuo Saiki 《Clinical & experimental metastasis》1998,16(1):94-104
A series of pseudo-peptide analogs of the Arg-Gly-Asp (RGD) sequence of fibronectin have been synthe-sized, and their anti-metastatic effects in mice and inhibitory effects on tumor cell invasion in vitro have been examined. The partially modified retro pseudo-peptide of RGD, Rrev-COCH2CO-D (FC-63), was more effective in inhibiting tumor metastasis than the original RGDS peptide. Replacement of the malonyl moiety of FC-63 with a carboxyethylene linkage (Rrev-COCH2CH2-D, FC-303 ) achieved more potent inhibition of lung metastasis of melanoma cells than FC-63. Among the analogs, FC-336, a p-xylylendiamine derivative having two FC-303 moieties, showed the most potent inhibitory effect on experimental lung metastasis produced by i.v. co-injection with B16-BL6 melanoma or colon 26 M3.1 cells in a dose-dependent manner. Multiple administrations of FC-336 after tumor inoculation also showed efficient therapeutic potency against spontaneous lung metastasis of B16-BL6 melanoma in mice. Furthermore, FC-336 effectively inhibited the invasion, migration and adhesion of tumor cells in vitro, but its inhibitory effects were not more than those of RGDS peptide. Zymography analysis revealed that FC-336 inhibited the degradation of gelatin substrate by matrix metalloproteinases (MMPs) produced by tumor cells, while the RGDS peptide did not affect the enzymatic degradation. These findings indicate that the pseudo-peptides of the RGD sequence, possessing the inhibitory property of the degradation by MMPs differently from original RGD-containing peptides, may be advantageous and useful in preventing tumor metastasis. © Rapid Science 1998 相似文献
82.
The effects of verapamil upon cerebrospinal fluid pressure (CSFP) were studied in twenty surgical patients without intracranial pathology who were divided into two groups of ten patients each: verapamil 0.075mg·kg–1 was given in group 1 and 0.15mg·kg–1 was given in group 2. A spinal needle was inserted into the subarachnoid space to permit continuous measurement of CSFP. Intravenous verapamil as a bolus produced a statistically significant increase in CSFP: from 6.0 ± 3.5 (mean ± SD) to 10.5 ± 4.3mmHg in group 1 (P < 0.01), and from 6.2 ± 3.1 to 12.6 ± 3.8mmHg in group 2 (P < 0.01). CSFP after verapamil attained its maximum in 0.5–1.5min, then gradually returned to control levels. Changes in CSFP were always associated with statistically significant decreases in arterial blood pressure and cerebral perfusion pressure, while the heart rate showed variable changes. It is concluded that a clinical dose of verapamil showed variable changes. It is concluded that a clinical dose of verapamil (0.075–0.15mg·kg–1) has no neurological side effects in patients without intracranial hypertension. However, it must be emphasized that verapamil may increase CSFP to undesirable levels and should be avoided in patients with compromised intracranial compliance.(Nishikawa T, Namiki A: The effects of verapamil on cerebrospinal fluid pressure in surgical patients. J Anesth 1: 132–136, 1987) 相似文献
83.
T Tsuda K Kubota K Yasuda S Nishikawa A Sugaya E Sugaya 《Journal of ethnopharmacology》1986,17(3):257-261
The Chinese herbal medicine, "Kanbaku-taiso-to" (KT) which is a mixture of Glycyrrhizae Radix, Triticii Semen and Zizyphi Fructus, sometimes shows marked effects on insomnia, infantile convulsions and emotional irritability. To elucidate the mechanism of the sedative effect of KT, effects of KT on the transmembrane ionic currents and local anesthetic action were examined and the following results were obtained. KT showed an inhibition of sodium, calcium and potassium currents in snail neurons. KT showed an inhibitory effect on pentylenetetrazol-induced bursting activity. KT had local anesthetic action on frog nerve fibers. Together with our previous study, these results suggest that KT has an inhibitory effect on hyperexcitability of the neuronal membrane and this is the main cause of the sedative effect of KT. 相似文献
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Nobuyoshi Kittaka MD PhD Satomi Nakajima MD Takaaki Hatano MD Yukiko Seto MD Hiroki Kusama MD PhD Saki Matsui MD PhD Minako Nishio MD PhD Fumie Fujisawa MD PhD Keiichiro Honma MD PhD Takahiro Nakayama MD PhD Yasuhiro Tamaki MD PhD 《The breast journal》2021,27(11):804-810
The ACOSOG Z0011 trial has resulted in the omission of axillary lymph node dissection (ALND) in early breast cancer patients with one or two metastatic sentinel lymph nodes (SLNs). There has been increasing interest in the necessity of intraoperative assessment of SLNs in patients treated based on the Z0011 criteria. We evaluated the utility of intraoperative assessment in these eligible patients. A total of 1396 patients were treated following the Z0011 criteria from April 2012 to December 2019. We examined the proportion and clinicopathological features of patients who underwent ALND due to three or more metastatic SLNs and the sensitivity of intraoperative assessment. Only 16 (1.1%) patients had three or more metastatic SLNs diagnosed by intraoperative assessment, and they immediately underwent ALND. Of the clinicopathological factors, high clinical tumor stage (p = 0.002) and high Ki-67 labeling index value (p = 0.056) were more likely to be associated with the presence of three or more metastatic SLNs. The major independent risk factor for three or more metastatic SLNs was high clinical tumor stage (OR 3.94 [95% CI 1.42–11.0]; p = 0.009). Intraoperative assessment had low sensitivity (70.5%) and a high false-negative rate (29.5%) in detecting SLN metastases. The main finding of our study was the small proportion of patients who required ALND due to three or more metastatic SLNs according to the Z0011 criteria. The Z0011 strategy enables intraoperative assessment of SLNs to be omitted in early breast cancer patients. 相似文献
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Key words dysrhythmia - isorhythmic dissociation - oscillation 相似文献
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Saeki T Salomon D Gullick W Mandai K Yamagami K Moriwaki S Takashima S Nishikawa Y Tahara E 《International journal of oncology》1994,5(3):445-451
The expression and localization of cripto-1 (CR-1) and epidermal growth factor receptor (EGFR) were assessed by immunocytochemistry in 41 human colorectal carcinomas, 57 adenomas, 9 hyperplastic polyps and in 98 noninvolved colonic mucosa samples that were adjacent to adenoma and/or carcinoma. Thirty-two (78.0%) and 19 (46%) carcinomas showed staining for CR-1 and EGFR, respectively, whereas 24 (42.0%) and 25 (43.8%) of the adenoma samples were reactive with the anti-CR-1 and anti-EGER antibodies, respectively. Two (22.2%) and 1 (11.1%) of the hyperplastic polyps demonstrated moderate levels of staining with anti-CR-1 and anti-EGFR antibodies. In contrast, none of the normal, noninvolved colonic mucosa samples reacted with the CR-1 antibody, whereas only 1 (1.0%) reacted with the EGFR antibody. Between EGFR and CR-1 expression, there was no significant association within either adenomas or carcinomas. A significant difference in the incidence for CR-1 expression was observed between adenomas and carcinomas (p<0.001). Within adenomas, the frequency of CR-1 was related to the histological degree of atypia. Immunostaining for p53 was also observed in 10 (24%) of the carcinomas, in 10 (17%) of the adenomas and in none of the hyperplastic polyps nor colonic mucosa samples. No statistically significant difference for p53 staining was observed between the adenomas and carcinomas. However, adenomas with moderate atypia exhibited relatively strong positive staining for p53 (p<0.05) compared to either adenomas with mild or severe atypia. A slight trend (p<0.05) for coexpression of p53 and CR-1 was detected in adenomas but not in carcinomas. These data demonstrate that CR-1 is a tumor marker for colon carcinomas and additionally that the expression of CR-1 may be an important factor in the early stages of colon cancer development during the adenomacarcinoma transition. 相似文献