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61.
Suppression of UV-induced mutations by wild-type p53 protein in human osteosarcoma cells 总被引:2,自引:0,他引:2
We have examined whether the tumour suppressor p53 protein suppressedUV-induced mutations in the hypoxathine-guanine phosphoribosyltransferase (HPRT) gene and in the supF gene of the shuttlevector plasmid pMY189. We used human osteosarcoma Saos-LP12cells, in which wild type (wt) p53 protein was induced by treatmentwith isopopyl-(ß-D-thiogalactopyranoside. The inductionof wt p53 protein suppressed UV-induced mutations but not spontaneousmutations in the HPRT gene. The frequency of UV-induced mutationsinduced by UV-irradiation of the plasmid was also significantlylower in cells with induced wt p53 protein than in the uninducedcells. In addition, we found that frequency of G : C to A :T transition mutations which occurred at the 3' base pair ofdipyrimidine sites were significantly lower in the cells withinduced wt p53 protein than in the uninduced cells. These findingssuggestthat wt p53 protein may play roles in modulating DNArepair pathway, resulting in the suppression of UV-induced mutations.
1To whom correspondence should be addressed 相似文献
62.
Noriaki Kameda Mineyuki Kagesawa Nobuyuki Hiruta Michio Akima Megumi Ohki Tsukasa Matsumoto 《Pathology international》1987,37(2):291-303
A 62-year-old female with primary leiomyosarcoma of the left femur is reported with a review of 21 cases reported in the literature. The resected specimen showed that the tumor extended from the femoral head to the diaphysis for 13cm in length. The tumor showed mainly intramedullary proliferation, but extraosseous growth was also noted at the great trochanter. Microscopic examination revealed well differentiated leiomyosarcoma characterized by interlacing bundles of fusiform cells with eosinophilic cytoplasm and rod-shaped hyperchromatic nuclei. PAP stain of actin on the tumor cells was positive. On electron microscopy, microfilament of 6–8 nm in diameter, dense bodies, plnocytotic vesicles, marginal attachment plate, and basal lamina were noted. The patient died with pulmonary metastasis, 1 year and 7 months after the operation. An autopsy showed metastases in the right pelvic cavity and bilateral lungs, and confirmed the primary site to be the left femur. 相似文献
63.
Hideo Yamaguchi Takayuki Nojima Tomonori Yagi Takeshi Masuda Tetsuto Sasaki 《Pathology international》1988,38(2):235-240
A rare case of high-grade surface osteosarcoma of the left ilum is reported. Trephine biopsy performed on a 31-year-old woman suffering from a huge tumor of the left buttock revealed high-grade osteosarcoma, and hemipel-vectomy was undertaken. The surgical specimen showed that the tumor was present on the surface of the left ilium. Ten months after the operation, the patient died of brain metastasis. From these results, we considered this case to be one of high-grade surface osteosarcoma. ACTA PATHOL JPN 38: 235 -240, 1988. 相似文献
64.
65.
Polymerase chain reaction (PCR) was applied to identify tissue-embedded ascarid nematode larvae. Two sequences of the internal transcribed spacer (ITS) regions of ribosomal DNA (rDNA), ITS1 and ITS2, of the ascarid parasites were amplified and compared with those of ascarid-nematodes registered in a DNA database (GenBank). The ITS sequences of the PCR products obtained from the ascarid parasite specimen in our laboratory were compatible with those of registered adult Ascaris and Toxocara parasites. PCR amplification of the ITS regions was sensitive enough to detect a single larva of Ascaris suum mixed with porcine liver tissue. Using this method, ascarid larvae embedded in the liver of a naturally infected turkey were identified as Toxocara canis. These results suggest that even a single larva embedded in tissues from patients with larva migrans could be identified by sequencing the ITS regions. 相似文献
66.
Doo Kyung Moon Kohtaro Osakada Tsukasa Maruyama Takakazu Yamamoto 《Macromolecular chemistry and physics.》1992,193(7):1723-1728
Oxidative polymerization of aniline using the H2O2-FeSO4 system gave polyaniline under mild conditions. The prepared powdery emeraldine base, a form of polyaniline, is blue black and shows high solubility in organic solvents (e.g., ca. 200 mg/mL in N-methylpyrrolidone). The number-average molecular weight (M n) of the polymer obtained was 1,3–1,7 · 104 (via gel permeation chromatography vs. polystyrene) and M w/M n = 1,6–2,2. Poly(2-ethylaniline) and poly-(2-propylaniline) with high molecular weights were also synthesized by this procedure in high yield. 相似文献
67.
Chang Richard L.; Huang Mou-Tuan; Wood Alexander W.; Wong Ching-Quo; Newmark Harold L.; Yagi Haruhiko; Sayer Jane M.; Jerina Donald M.; Conney Allan H. 《Carcinogenesis》1985,6(8):1127-1133
Ellagic acid, quercetin and robinetin were tested for theirability to antagonize the tumor-initiating activity of benzo[a]pyrene(B[a]P) and (±)-7ß, 8-dihydroxy-9, 10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene(B[a]P 7,8-diol-9,10-epoxide-2), the ultimate carcinogenic metaboliteof benzo[a]pyrene. Ellagic acid, robinetin or quercetin (2500nmol) had no tumor-initiating activity on mouse skin, but thetopical application of 2500 nmol of ellagic acid 5 min beforea tumor-initiating dose of 200 nmol of B[a]P 7,8-diol-9,10-epoxide-2caused a 5966% inhibition in the number of skin tumorsper mouse that were observed after 1520 weeks of promotionwith 12-O-tetradecanoylphorbol-13-acetate. Similar treatmentwith 2500 nmol of robinetin or quercetin caused a statisticallyinsignificant 1624% inhibition in the tumor-initiatingactivity of 200 nmol of B[a]P 7,8-diol-9,10-epoxide-2 applied5 min later. Treatment of mice with 2500 nmol of ellagic acid5 min before the application of 50 nmol of B[a]P inhibited themean number of skin tumors per mouse by 2833% after 1520weeks of promotion, but these decreases were not statisticallysignificant. Robinetin and quercetin had little or no effecton the tumor-initiating activity of B[a]P on mouse skin. Treatmentof preweanling mice with 1/7, 2/7 and 4/7 of the total doseof ellagic acid (300 nmol), robinetin (1400 nmol), myricetin(1400 nmol) or quercetin (1400 nmol) i.p. on their first, eighthand fifteenth day of life, respectively, did not cause the formationof tumors in animals that were killed 911 months later.Similar treatment of preweanling mice with the above doses ofthe phenolic compounds 10 min before the i.p. injection of atotal dose of 30 nmol of B[a]P 7,8-diol-9,10-epoxide-2 duringthe animal's first 15 days of life caused a 4475% inhibitionin the number of diol-epoxide-induced pulmonary tumors per mouse.Similar treatment with these plant phenols had little or noeffect on B[a]P-induced pulmonary tumors. 相似文献
68.
Goto Y Takahashi K Harada J Sugiura Y Aso K Takanami C Nakajima K Yagi Y Urano H 《Journal of anesthesia》1987,1(2):178-182
Concerning the classification of ventilators, Elam (1958), Faireley (1959), and Hunter (1961) reported some simple ones such as pressure limited, volume limited, pressure preset, or volume preset models. Mapleson (1969) also classified them by the generating force or cycling together with the above-mentioned types.The latest ventilators applicable to patients with respiratory failure usually have some cut-off function at high airway pressures as a safety measure. Therefore, all of them belong to the pressure limited type. Some ventilators are of two types such as the time cycled and pressure cycled type.Therefore, we attempted to classify ventilators into four groups, i.e. the time cycled, volume cycled, pressure cycled and selective time-pressure cycled types according to the fundamental mode of ventilator function, the so-called change of cycling from inspiration to expiration. Each group was further divided into subgroups according to preset dials such as respiratory rate, I/E ratio, inspiration time, expiration time, tidal volume, flow rate and airway pressure.By this method, fifty one ventilators on the market in Japan can be classified without overlapping. Although this classification seems complex, it will be of use in selecting ventilators by emphasizing preset dials according to the users needs, ability or both.(Goto Y, Takahashi K, Harada J et al.: A consideration on the new classification of latest lung ventilators. J Anesth 1: 178–182, 1987) 相似文献
69.
Mary Jane Yagi Mohammed Zanjani James F. Holland J. George Bekesi 《Cancer chemotherapy and pharmacology》1984,12(2):70-76
Summary A new synthetic tripeptide (p-F-Phe-m-bis-(2-chloroethyl)amino-Phe-Met ethoxy HCl), PTT.119, was demonstrated to have significant cancericidal activity against seven in vitro tumor cell lines of different origins and etiologies and against primary human AMML, ALL, and hairy cell leukemias. Viabilities of each murine tumor and rabbit, marmoset, and human leukemia and lymphoma line were significantly reduced by treatment with 1–50 g PTT.119 in media containing serum. Continuous 24-h exposure or pulse treatment as short as 15 and 30 min with the tripeptide resulted in irreversible damage to the tumor cells. Under identical treatment conditions, freshly isolated human leukemic cells, particularly ALL lymphoblasts, were even more susceptible to PTT.119 than any of the tested tumor cell models.Examination of the parameters of PTT.119 activity revealed that reductions of tumor cell survival were dependent on the concentration of the tripeptide. Prolongation of PTT.119 exposure from 15 min to 24 h increased the rates of tumor cell death but did not proportionally reduce the numbers of surviving cells. Assessment of tumor cell viabilities for 5 consecutive days following pulse exposure to PTT.119 demonstrated increasing reductions in tumor cell survival, which were greatest 5 days after treatment with the tripeptide.The cancericidal activity of PTT.119 was compared with its three parental components either as individual agents or as a mixture. Both the alkylator moiety, m-sarcolysin (m.L.SL) alone or together with p-fluoro-phenylalanine and l-methionine ethoxy HCl, and l-PAM (l-phenylalanine mustard), the p-isomer of m.L.SL, were 1.5- to 3-fold less cytotoxic to L1210 leukemia and MJY-alpha mammary tumor cells than PTT.119. Covalent linkage of the amino acid residues to m.L.SL yielded a molecule with greatly augmented cancericidal activity capable of acting against a broad spectrum of tumor cells. 相似文献
70.
Kenya Kusunose Yuichiro Okushi Yoshihiro Okayama Robert Zheng Miho Abe Michikazu Nakai Yoko Sumita Takayuki Ise Takeshi Tobiume Koji Yamaguchi Shusuke Yagi Daiju Fukuda Hirotsugu Yamada Takeshi Soeki Tetsuzo Wakatsuki Masataka Sata 《Nutrients》2021,13(2)
A broad range of chronic conditions, including heart failure (HF), have been associated with vitamin D deficiency. Existing clinical trials involving vitamin D supplementation in chronic HF patients have been inconclusive. We sought to evaluate the outcomes of patients with vitamin D supplementation, compared with a matched cohort using real-world big data of HF hospitalization. This study was based on the Diagnosis Procedure Combination database in the Japanese Registry of All Cardiac and Vascular Datasets (JROAD-DPC). After exclusion criteria, we identified 93,692 patients who were first hospitalized with HF between April 2012 and March 2017 (mean age was 79 ± 12 years, and 52.2% were male). Propensity score (PS) was estimated with logistic regression model, with vitamin D supplementation as the dependent variable and clinically relevant covariates. On PS-matched analysis with 10,974 patients, patients with vitamin D supplementation had lower total in-hospital mortality (6.5 vs. 9.4%, odds ratio: 0.67, p < 0.001) and in-hospital mortality within 7 days and 30 days (0.9 vs. 2.5%, OR, 0.34, and 3.8 vs. 6.5%, OR: 0.56, both p < 0.001). In the sub-group analysis, mortalities in patients with age < 75, diabetes, dyslipidemia, atrial arrhythmia, cancer, renin-angiotensin system blocker, and β-blocker were not affected by vitamin D supplementation. Patients with vitamin D supplementation had a lower in-hospital mortality for HF than patients without vitamin D supplementation in the propensity matched cohort. The identification of specific clinical characteristics in patients benefitting from vitamin D may be useful for determining targets of future randomized control trials. 相似文献