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71.
Yasuhiro Yoshikawa Hiroshi Tsuruoka Mineo Matsumoto Takeshi Haga Tatsuo Shioda Hiroshi Shibuta Takeshi A. Sato Kazuya Yamanouchi 《Virus genes》1990,4(2):151-161
The nucleotide sequence of a cloned cDNA corresponding to the P+M dicistronic mRNA of a subacute sclerosing panencephalitis (SSPE) virus was determined and compared with data of measles virus (MV). The dicistronic mRNA of the SSPE virus consisted of the 3 proximal 626 nucleotides of P mRNA, intercistronic trinucleotides, a full length of M mRNA, and 75 poly A nucleotides. The part encoding the P protein had a high homology to MV, except at the noncoding region. The terminating consensus sequence of the P gene and the intercistronic trinucleotides of the SSPE virus were CTAC(A)6 and CCT; in MV they are TTAT(A)6 and CTT, respectively. In the M gene, the starting consensus sequence was exactly the same as MV, but at the 5 proximal end, one third of this gene was different: The first ATG codon of the MV M gene signaling opening of the reading frame was changed to ACG in the SSPE virus and one long open reading frame started from the third ATG codon. The stop codon (TAG) of the MV M gene was also changed to CAG in the SSPE virus. Thus, the deduced SSPE-virus M protein lacked 50 amino acids at the amino terminal and had 15 extra amino acids at the carboxyl end when compared with the MV M protein. 相似文献
72.
The present study introduces the principle of atomic force microscopy (AFM) and reviews our results of human metaphase chromosomes
obtained by AFM. AFM imaging of the chromosomes revealed that the chromatid arm was not uniform in structure but had ridges
and grooves along its length, which was most prominent in the late metaphase. The arrangement of these ridges and grooves
was roughly symmetrical with the counterpart of the paired sister chromatids. AFM imaging of banded chromosomes also showed
that the ridges and grooves were related to the G/Q-positive and G/Q-negative bands, respectively. At high magnification,
the chromatid was seen to be produced by the compaction of highly twisted chromatin fiber loops, and its compaction tended
to be stronger in the ridged regions of the chromosomes than in the grooved regions. Our AFM studies also showed the presence
of catenation of chromatin fibers between the ridged portions of the chromatid in the late metaphase. Thus, AFM is useful
for obtaining the three-dimensional surface topography not only in ambient conditions but also in physiological liquid conditions,
and is expected to be an attractive tool for investigating the structure of chromosomes. 相似文献
73.
Takahashi Toshinari Beppu Takanobu Hidaka Yuji Hosoya Tatsuo 《Clinical and experimental nephrology》2021,25(12):1336-1345
Clinical and Experimental Nephrology - Dotinurad is a selective urate reabsorption inhibitor (SURI), which selectively inhibits URAT1 to lower serum uric acid levels in patients with hyperuricemia.... 相似文献
74.
Yoshikuni Kudo Toru Egashira Fusako Takayama Yasumitsu Yamanaka Tatsuo Shimada 《Archives of toxicology》1993,67(7):502-509
To explain the mechanism of renal injury caused by liver ischemia-reperfusion, we investigated biochemical and morphological changes in the liver and kidney in rats. After reperfusion following 60 min of liver ischemia, numerous changes were found. The level of serum transaminases and lipid peroxide formation in the liver tissue increased significantly. Electron microscopic studies revealed that most of the hepatocytes had swollen mitochondria and clumping of the nuclear chromatin. The sinusoidal endothelium was disrupted and the sinusoidal lumen was filled with numerous erythrocytes. Blood endotoxin concentration, plasma lipid peroxide levels, and serum -glucuronidase activities were significantly higher than in the control group. Biochemical and morphological renal injury was also observed. Tissue lipid peroxide levels increased in both the kidney and the liver. Microscopic examination revealed damage to the renal tubules, including interstitial edema, dilatation of the lumen, and granular casts derived from necrotic cells in the proximal convoluted tubule. The levels of urinary N-acetyl--d-glucosaminidase (NAG) in the liver ischemia-reperfusion group were also higher than in the control group. These results suggest that the renal injury was caused by an increase in endotoxin, lipid peroxide, and lysosomal enzymes in the blood following the liver injury induced by the ischemia-reperfusion. 相似文献
75.
Keisuke Yoshihama Hideki Mutai Mariko Sekimizu Fumihiro Ito Shin Saito Shintaro Nakamura Takuya Mikoshiba Ryoto Nagai Akiko Takebayashi Fuyuki Miya Kenjiro Kosaki Hiroyuki Ozawa Tatsuo Matsunaga 《Clinical genetics》2023,103(4):466-471
Carotid body tumor (CBT) is classified as a paraganglioma (PGL). Here, we report the genetic background, protein expression pattern, and clinical findings of 30 Japanese CBT cases. Germline pathogenic or likely pathogenic (P/LP) variants of genes encoding succinate dehydrogenase subunits (SDHs) were detected in 15 of 30 cases (50%). The SDHB variants were the most frequently detected, followed by SDHA and SDHD variants. One case with SDHAF2 variant was bilateral CBT, and other two multiple PGL cases were not detected P/LP variants. The three cases with germline variants that could be tested did not have somatic P/LP variants of the same genes. Immunohistochemical analysis showed negative SDHB signals in CBT tissues in five cases with germline P/LP variants of SDHB, SDHD, or SDHA. In addition, SDHB signals in CBT tissues were negative in four of nine cases without germline P/LP variants of SDHs. These findings suggest the involvement of unidentified molecular mechanisms affecting SDHs. 相似文献
76.
Iwabuchi Satoru Handa Masashi Usuda Katsuo Sato Masami Kondo Takashi Tanita Tatsuo Fujimura Shigefumi 《Surgery today》1994,24(11):1014-1018
A 52-year-old Japanese man with a slow-growing chondroma originating from the sternal bone was referred to our hospital. A subtotal resection of the sternum was performed, hereafter termed the sandwich method, and an originally designed prosthesis made from ultra-high-molecular-weight polyethylene and Marlex mesh was used for reconstruction. The postoperative course was uneventful without any symptoms due to paradoxical movement of the chest or regional abscess, and no disturbance in the movement of the upper limbs, such as a surgical sequelae, was observed. 相似文献
77.
Motonobu Kameyama Kiichi Ishiwata Yuji Tsurumi Jun Itoh Kiyotaka Sato Ryuichi Katakura Takashi Yoshimoto Jun Hatazawa Masatoshi Ito Tatsuo Ido 《Journal of neuro-oncology》1995,23(1):53-61
Summary Positron emission tomography was used to investigate the metabolism of nucleic acids by18F-fluoro-2-deoxyuridine (18F-FUdR) in 22 patients with gliomas. Sixteen cases of high grade glioma clearly demonstrated a region of high activity with a differential absorption rate (DAR) of 0.64 ± 0.34. Six cases of low grade glioma failed to reveal a positive image of the tumor and the DAR in tumor was 0.21 ± 0.042 (p < 0.01). This PET-18F-FUdR study succeeded in differentiating high and low grade gliomas from the view point of nucleic acid metabolism. 相似文献
78.
Yoshikazu Noguchi Tatsuo Makino Takaki Yoshikawa Katsutoshi Nomura Kuniyasu Fukuzawa Akihiko Matsumoto Takuko Yamada 《Surgery today》1996,26(1):36-41
This study was conducted to investigate the role of tumor necrosis factor- (TNF-) and interleukin-2 (IL-2) in inducing cancer cachexia, and the results were compared with those obtained from our previous study on Fisher 344 rats with methylcholanthrene-induced sarcoma. Three groups of male Fisher 344 rats received one of the following regimens: 4×104 IU of human recombinant TNF- per rat per day subcutaneously (sc) for 5 consecutive days (n=5), 3.5×105 U human recombinant IL-2 per rat per day sc for 14 consecutive days (n=5), or normal saline (n=5). The activities of both phosphoenolpyruvate carboxykinase (PEPCK) and malic enzyme (ME) were increased slightly in the IL-2 group. Furthermore, LPL activity was significantly increased in the adipose tissue of the TNF group and in the cardiac muscle of the IL-2 group, but not in that of the TNF group. These results show that there is a significant difference between the metabolic alterations seen in the tumor-bearing state and those induced by either TNF- or IL-2 alone. Thus, it is unlikely that IL-2 or TNF- is the sole mediator of cancer cachexia in this tumor and rat model. 相似文献
79.
Pelvic insufficiency fractures in postmenopausal woman with advanced cervical cancer treated by radiotherapy. 总被引:3,自引:0,他引:3
Ichiro Ogino Naoyuki Okamoto Yoshimi Ono Tatsuo Kitamura Hiroki Nakayama 《Radiotherapy and oncology》2003,68(1):61-67
PURPOSE: To assess the predisposing factors and clinical characteristics of pelvic insufficiency fractures (PIF) in postmenopausal women with pelvic irradiation. MATERIAL AND METHODS: A total 335 postmenopausal patients with cervical cancer of the intact uterus treated with radiation therapy between 1983 and 1998 were reviewed. Total external dose was delivered between 45 and 50.4 Gy with parallel opposed anteroposterior portals. Total brachytherapy dose at point A was delivered between 10 and 36 Gy. PIF were diagnosed by bone scintigraphy and confirmed by computed tomography. The cumulative incidence of symptomatic PIF was estimated by actuarial methods. Potential risk factors (age, weight, type II diabetes, delivery, menopause, total external dose, total brachytherapy dose) were assessed. RESULTS: Fifty-seven (17.0%) of 335 patients were diagnosed as having PIF. Forty-seven patients were symptomatic and ten were asymptomatic. Parameters carrying a significant association with PIF were body weight 49 kg or below (P=0.044) in stepwise logistic regression analysis. The cumulative incidence of symptomatic PIF at 5 years was 17.9% calculated by the Kaplan-Meier method. A body weight of 49 kg or below and more than three deliveries were identified as having a significant effect on symptomatic PIF in univariate analysis (P=0.021, P=0.003, log-rank test) and Cox life table regression analysis (P=0.038, P=0.013). Five patients required narcotic agents and eight patients required hospital admission. CONCLUSIONS: We should consider reducing the dose contribution to the sacrum and sacroilac joints, without underdosing the tumor, especially in postmenopausal women with many deliveries or low body weight. 相似文献
80.
Induction of apoptosis in multi-drug resistant (MDR) human glioblastoma cells by SN-38, a metabolite of the camptothecin derivative CPT-11 总被引:5,自引:0,他引:5
Shouji Nakatsu S. Kondo Yasuko Kondo Dali Yin John W. Peterson Rami Kaakaji Tatsuo Morimura Haruhiko Kikuchi Juji Takeuchi Gene H. Barnett 《Cancer chemotherapy and pharmacology》1997,39(5):417-423
The overexpression of the multidrug resistance (mdr1) gene and its product, P-glycoprotein (P-gp), is thought to limit the successful chemotherapy of human tumors. Recent studies
demonstrate that SN-38, a metabolite of the camptothecin (CPT) derivative CPT-11, has antitumor effects on several tumors,
but the mechanisms responsible for its cytotoxicity remain unclear. We therefore determined whether SN-38 has cytotoxic effects
on MDR human glioblastoma GB-1 cells and non-MDR human glioblastoma U87-MG cells. Furthermore, we determined what role SN-38
plays in the induction of cytotoxicity in these tumor cells. In this study, we demonstrated that SN-38 had significantly stronger
antitumor effects on GB-1 and U-87MG cells than did CPT (P<0.01 and P<0.05, respectively). In addition, findings obtained using a DNA fragmentation assay, Hoechst 33258 staining, in situ end-labeling
and cell cycle analysis demonstrated that SN-38 induced apoptosis in these tumors. Our results suggest that SN-38 has a stronger
antitumor effect on malignant glioma cells regardless of MDR expression than does CPT, and therefore can be considered a new
chemotherapeutic agent potentially effective in the treatment of human primary or recurrent malignant gliomas resistant to
chemotherapy.
Received: 6 October 1995/Accepted 29 June 1996 相似文献