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101.
102.
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
103.
Kasahara K Taguchi T Yamasaki I Kamada M Yuri K Shuin T 《Cancer Genetics and Cytogenetics》2002,137(1):59-63
In this study, we examined nine cases of advanced Japanese prostate cancer by comparative genomic hybridization (CGH) to detect chromosomal imbalances across the entire genome and to identify several new regions likely to contain genes important to the development and progression of this disease. These cases had been previously examined for numerical chromosomal aberrations by fluorescence in situ hybridization (FISH). By CGH, the following regions were found to be over-represented (gains), with fluorescence ratio values higher than the threshold: 4p, 6p, 8q, 11q, 12q, 15q, 16p, 17q, 20, and 21 (>4 cases); underrepresentation (losses) involved: 1q, 4q, 5q, 6q, 13q, 14q, and 22 (>4 cases). The shortest regions of overlap (SRO) of gains were noted at 8q24.1 through q24.3, 12q23, and 17q23 through q24 (>5 cases). The SRO of losses were seen at 5q14 through q21, 6q16.1 through q21, 13q21.3 through q22, and 14q21 (>5 cases). Notably, the gain of chromosomes 8 and 12 by CGH was in agreement with the FISH data, suggesting that the gain of chromosomes 8 and 12 may play an important role in prostate carcinogenesis. The genes on the SRO regions were also discussed in relation to oncogenes and bone metastases. 相似文献
104.
Persistent effect of a low dose of preadministered diethylnitrosamine on the induction of enzyme-altered foci in rat liver 总被引:1,自引:0,他引:1
Takahashi Seiichi; Tsutsumi Masahiro; Nakae Dai; Denda Ayumi; Kinugasa Tetsuo; Konishi Yoichi 《Carcinogenesis》1987,8(4):509-513
The effect of a low dose of preadministered diethylnitrosamine(DEN) on the induction of enzyme-altered foci in the liversof male full-grown Fischer 344 rats was studied. As a pretreatment,DEN at a dose of 10 mg/kg body wt was injected i.p. At varioustimes after DEN pretreatment a complete initiation, consistingof administration of the same dose of DEN by the same routein rats subjected to partial hepatectomy (PH), was performed,followed by application of selection pressure. Enzyme-alteredfoci stained with -glutamyltrans-peptidase (-GTP) and glutathioneS-transferase placental form (GST-P) were then assayed. Decreasesin the numbers and areas of foci in the rats which receivedsaline + PH 14 or 28 days after DEN pretreatment were observedin comparison with rats which received saline + PH immediatelyafter DEN. On the other hand, the numbers and areas of fociwere not decreased in rats which received the complete initiation,consisting of DEN + PH, at various times after DEN pretreatmentwhen compared with rats which received these at the same timeas the DEN pretreatment. This persistent effect of DEN pretreatmenton the complete initiation lasted up to 182 days after the timeof DEN pretreatment. In this experiment, GST-P was found tobe a more sensitive marker for the detection of putative preneoplasticliver-cell foci than -GTP. 相似文献
105.
Nakagawa Ichiro Park HunSoo Kotsugi Masashi Motoyama Yasushi Myochin Kaoru Takeshima Yasuhiro Matsuda Ryosuke Nishimura Fumihiko Yamada Syuichi Takatani Tsunenori Kichikawa Kimihiko Nakase Hiroyuki 《Neurosurgical review》2021,44(3):1493-1501
Neurosurgical Review - The present study aimed to determine the incidence of intraprocedural motor-evoked potential (MEP) changes and to correlate them with intraprocedural ischemic complications... 相似文献
106.
107.
Mitsuhiro Fukao Yuichi Hattori Morio Kanno Ichiro Sakuma Akira Kitabatake 《British journal of pharmacology》1997,120(7):1328-1334
- The aim of the present study was to identify the sources of Ca2+ contributing to acetylcholine (ACh)-induced release of endothelium-derived hyperpolarizing factor (EDHF) from endothelial cells of rat mesenteric artery and to assess the pathway involved. The changes in membrane potentials of smooth muscles by ACh measured with the microelectrode technique were evaluated as a marker for EDHF release.
- ACh elicited membrane hyperpolarization of smooth muscle cells in an endothelium-dependent manner. The hyperpolarizing response was not affected by treatment with 10 μM indomethacin, 300 μM NG-nitro-L-arginine or 10 μM oxyhaemoglobin, thereby indicating that the hyperpolarization is not mediated by prostanoids or nitric oxide but is presumably by EDHF.
- In the presence of extracellular Ca2+, 1 μM ACh generated a hyperpolarization composed of the transient and sustained components. By contrast, in Ca2+-free medium, ACh produced only transient hyperpolarization.
- Pretreatment with 100 nM thapsigargin and 3 μM cyclopiazonic acid, endoplasmic reticulum Ca2+-ATPase inhibitors, completely abolished ACh-induced hyperpolarization. Pretreatment with 20 mM caffeine also markedly attenuated ACh-induced hyperpolarization. However, the overall pattern and peak amplitude of hyperpolarization were unaffected by pretreatment with 1 μM ryanodine.
- In the presence of 5 mM Ni2+ or 3 mM Mn2+, the hyperpolarizing response to ACh was transient, and the sustained component of hyperpolarization was not observed. On the other hand, 1 μM nifedipine had no effect on ACh-induced hyperpolarization.
- ACh-induced hyperpolarization was nearly completely eliminated by 500 nM U-73122 or 200 μM 2-nitro-4-carboxyphenyl-N,N-diphenylcarbamate, inhibitors of phospholipase C, but was unchanged by 500 nM U-73343, an inactive form of U-73122. Pretreatment with 20 nM staurosporine, an inhibitor of protein kinase C, did not modify ACh-induced hyperpolarization.
- These results indicate that the ACh-induced release of EDHF from endothelial cells of rat mesenteric artery is possibly initiated by Ca2+ release from inositol 1,4,5-trisphosphate (IP3)-sensitive Ca2+ pool as a consequence of stimulation of phospholipid hydrolysis due to phospholipase C activation, and maintained by Ca2+ influx via a Ni2+- and Mn2+-sensitive pathway distinct from L-type Ca2+ channels. The Ca2+-influx mechanism seems to be activated following IP3-induced depletion of the pool.
108.
Nishiyama M Nakae K Yukawa S Hashimoto T Inaba G Mochizuki M Sakane T 《Environmental health and preventive medicine》1999,4(3):130-134
The 4th nationwide epidemiological survey on Behçet disease (BD), which included all patients with BD at 1,200 hospitals selected at random from 10,081 hospitals in Japan, was carried out by the BD Research Committee of the Ministry of Health and Welfare in 1991 to examine the epidemiological features of BD in Japan by comparing with previous surveys. 3,938 patients from these hospitals were examined by the Japanese diagnostic criteria of BD (JCBD) revised in 1987 and the International criteria for classification of BD (ICBD). Among these 3,938 patients, 622 patients were only suspected of having BD or clinical signs of the disease were unknown, and most of these patients were incompatible with the ICBD. So these patients were excluded from the study of epidemiological features. The average patients age has risen 7–8 years over the last 20 years and the average age of onset in both sexes increased by about 3 years from 1972 to 1991. While a decrease in the sex ratio was seen in the complete-type and the incomplete-type BD without ocular symptoms, a sustained high sex ratio was shown in incomplete-type BD with ocular symptoms. The positive rate of HLA-B51 antigen was 54.9% (men: 56.9%, women: 52.2%) significantly higher than die 15–16% in healthy subjects but it might have been gradually decreasing. Also the clinical course of BD has become too mild for prognosis. According to diese epidemiological features of BD, the clinical manifestation of BD in Japan might have become the Western type of BD. 相似文献
109.
Sakurada I Kido T Suwazono Y Kobayashi E Kinouchi N Nogawa K 《Environmental health and preventive medicine》1999,4(1):30-33
An investigation on the health status of 79 male preparatory school students lodging at a dormitory in Japan was carried out
by questionnaire on lifestyles, subjective symptoms and mental status, as compared with two control groups: 73 medical students
and 36 new employees. About 83 % of them slept less than 6 hours and 70 % of them did not exercise. Many students are troubled
with back pain or lumbago(47%), sensation of incomplete bladder emptying(l6%), loss of visual acuity(55%) and eye fatigue(65%).
Self-rating depression scale score of preparatory school students was not significantly higher than those of the control groups.
The lifestyles of preparatory school students found to be very restricted and strained. However, no significant differences
on mental adverse health effects was found among three groups. 相似文献
110.
Use of ultrasound-guided percutaneous needle biopsy in the diagnosis of mediastinal tumors 总被引:1,自引:0,他引:1
Yoshimi Otani Ichiro Yoshida Susumu Ishikawa Akio Ohtaki Osamu Kawashima Toru Takahashi Yasushi Sato Yasuo Morishita 《Surgery today》1996,26(12):990-992
We herein report the usefulness of ultrasoundguided percutaneous needle biopsy for histological diagnosis in 18 patients with mediastinal tumors. Computed tomography revealed these tumors to be in contact with the chest wall. The preoperative diagnosis was thymoma in 7 patients, germinoma in 5, neurogenic tumor in 3, and other in 3. The most commonly encountered indication for an ultrasound-guided percutaneous needle biopsy was an anterior mediastinal lesion (78%; 14 of 18 patients). In 16 (89%) of the 18 patients, the biopsy diagnosis corresponded to the post-operative diagnosis. No complications were encountered in any of the patients. This new technique of ultrasound-guided percutaneous needle biopsy is both relatively simple and highly accurate and may thus be useful for outpatients. Preoperative ultrasound-guided percutaneous needle biopsy is thus considered to be a safe and reliable method for the histological diagnosis of mediastinal tumors, and a good alternative to traditional biopsy techniques such as mediastinoscopy or thoracotomy.Presented at the 11th Biennial Asian Congress on Thoracic and Cardiovascular Surgery, Kuala Lumpur, Malaysia, November, 21–25, 1993. 相似文献