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991.
DNA-binding polarity of human replication protein A positions nucleases in nucleotide excision repair 总被引:15,自引:0,他引:15 下载免费PDF全文
Wouter L. de Laat Esther Appeldoorn Kaoru Sugasawa Eric Weterings Nicolaas G.J. Jaspers Jan H.J. Hoeijmakers 《Genes & development》1998,12(16):2598-2609
The human single-stranded DNA-binding replication A protein (RPA) is involved in various DNA-processing events. By comparing the affinity of hRPA for artificial DNA hairpin structures with 3′- or 5′-protruding single-stranded arms, we found that hRPA binds ssDNA with a defined polarity; a strong ssDNA interaction domain of hRPA is positioned at the 5′ side of its binding region, a weak ssDNA-binding domain resides at the 3′ side. Polarity appears crucial for positioning of the excision repair nucleases XPG and ERCC1–XPF on the DNA. With the 3′-oriented side of hRPA facing a duplex ssDNA junction, hRPA interacts with and stimulates ERCC1–XPF, whereas the 5′-oriented side of hRPA at a DNA junction allows stable binding of XPG to hRPA. Our data pinpoint hRPA to the undamaged strand during nucleotide excision repair. Polarity of hRPA on ssDNA is likely to contribute to the directionality of other hRPA-dependent processes as well. 相似文献
992.
Immunohistochemical,ultrastructural and biochemical studies of an amylase-producing breast carcinoma
Hideo Inaji Hiroki Koyama Masahiko Higashiyama Shinzaburo Noguchi Hitoshi Yamamoto Osamu Ishikawa Kaoru Omichi Takeshi Iwanaga Akira Wada 《Virchows Archiv : an international journal of pathology》1991,419(1):29-33
Summary We describe a breast cancer with ectopic production of amylase, found in the patient's serum, urine and in the tumour. Clinically, serum amylase levels reflected both the progression of the disease and regression induced by various therapies. Using agarose gel electrophoresis and a wheat protein inhibitor assay, the predominant serum amylase appeared to be identical to pancreatic-type isoenzyme. However, the action mode analysis using a new fluorogenic substrate revealed that the serum contained non-salivary, non-pancreatic amylase. The tumour had microscopic features of invasive ductal carcinoma with some argyrophilic differentiation. The component cells stained positively for amylase, and ultrastructurally numerous secretory granules were seen. 相似文献
993.
994.
Tetsuya Murata Toshihiko Soga Kazuhiro Tajima Kaoru Saito Yoshinori Komeda Sergio Ossamu Loshii Taizo Shiraishi Teruyo Sakakura Ryuichl Yatani 《Pathology international》1994,44(2):138-144
Sarcomatoid carcinoma is a rare variant of malignant tumor arising from the urinary tract. This tumor had been termed carcinosarcoma because of its carcinomatous and sarcomatous components. There is still some confusion in the terminology between true carcinosarcoma and sarcomatoid carcinoma; however, the latter is now regarded as primarily a malignant epithelial tumor with pseudosarcomatous transformation.
Four cases of sarcomatoid carcinoma arising from the urinary tract are reported. The patients were a 77 year old female, and three males aged 62, 69 and 80 years. All but the eldest patient complained of gross hematurla. Surgical removal was performed in the younger three cases, and an autopsy was done in the remaining case. All the tumors were macroscopically polypoid. Histopathologic examination revealed fasciculated spindle-cell tumors with myxold stroma or malignant fibrous histiocytoma-like spindle cell tumors. The epithelial nature was proven in these sarcomatous cells by immunohistochemical andlor electron-microscopic examinations. Only a small amount of squamous cell carcinoma components was also evident in the latter three cases. Although the younger three patients were alive at 44, 23 and 39 months'follow-up, respectively, constant careful monitoring Is recommended. 相似文献
Four cases of sarcomatoid carcinoma arising from the urinary tract are reported. The patients were a 77 year old female, and three males aged 62, 69 and 80 years. All but the eldest patient complained of gross hematurla. Surgical removal was performed in the younger three cases, and an autopsy was done in the remaining case. All the tumors were macroscopically polypoid. Histopathologic examination revealed fasciculated spindle-cell tumors with myxold stroma or malignant fibrous histiocytoma-like spindle cell tumors. The epithelial nature was proven in these sarcomatous cells by immunohistochemical andlor electron-microscopic examinations. Only a small amount of squamous cell carcinoma components was also evident in the latter three cases. Although the younger three patients were alive at 44, 23 and 39 months'follow-up, respectively, constant careful monitoring Is recommended. 相似文献
995.
Noriomi Suzuki Takafumi Suzuki Kaoru Ogawa Hiroyuki Yamagishi 《Acta oto-laryngologica》2020,140(9):736-740
AbstractBackground: Individuals with 22q11.2 deletion syndrome (22q11.2DS) exhibit various phenotypes.Objective: To compare the clinical and otorhinolaryngological features of Japanese patients with 22q11.2DS with those of patients reported in Western literature.Materials and methods: We retrospectively assessed the medical records of 17 Japanese patients with 22q11.2DS and compared our findings with previously reported findings in Western literature.Results: Hearing loss was the most frequent complaint (n?=?8, 47%), followed by articulation disorders and/or nasopharyngeal closure failure (n?=?4, 24%) and language development delay (n?=?2, 12%). Ten patients (59%) had hearing loss regardless of the chief complaint (total 15 ears – mild, 9; moderate, 6). Four patients had bilateral hearing loss. One patient (6%) underwent tympanostomy tube placement for refractory exudative otitis media, another (6%) underwent myringoplasty, and three patients (18%) underwent tympanoplasties for chronic otitis media or middle ear malformation. Previous studies in Western countries reported similar results in terms of frequency of hearing loss, severity of hearing loss, and the percentage of middle ear malformations.Conclusions: The otorhinolaryngological characteristics of Japanese patients with 22q11.2DS were similar to those in Western countries. Hearing loss was primarily caused by disorders like otitis media and middle ear malformation.Significance: Our findings may aid treatment planning for Asian patients with 22q11.2DS. 相似文献
996.
Naoki Oishi Seiichi Shinden Sho Kanzaki Hideyuki Saito Yasuhiro Inoue Kaoru Ogawa 《European archives of oto-rhino-laryngology》2013,270(2):443-448
The aim of this study was to assess how tinnitus retraining therapy (TRT) employing monaural noise generators (NGs) affects tinnitus patients. Ninety-five patients with chronic tinnitus were included in this study. All received directive counseling and monaural NGs without any other combination treatment. Effects were evaluated with the Tinnitus Handicap Inventory (THI) 6, 12, and 24 months after the start of treatment. Multiple regression analysis was used to evaluate factors associated with improvement of THI scores. We observed a significant improvement in the average THI scores, which ranged from 59 at baseline to 36 after 6 months and were stable up to 24 months. Severely distressed (SD) patients experienced more benefits from the therapy than moderately distressed (MD) patients. Multiple regression analysis revealed that the presence of transient anxiety symptoms, measured by the state section of the State Trait Anxiety Inventory at the beginning of treatment, were associated the most to a decline in THI scores in SD patients. Pure-tone average at three mid frequencies was a negatively contributing factor. Analysis of MD patients did not provide a good model. In conclusion, TRT employing monaural NGs was an effective intervention especially for SD patients, although plateau of the effects after 6 months may be indicative of limitation of applying NGs monoaurally. Reducing the patients’ hearing handicap may reinforce the effects of TRT in SD patients. Additional evaluation and interventions for both SD and MD patients might be needed. 相似文献
997.
Tatsuya Yamada MD Junzo Takeda MD Kaoru Koyama MD Hiromasa Sekiguchi MD Kazuaki Fukushima MD Taro Kawazoe MD 《Journal of cardiothoracic and vascular anesthesia》1994,8(6)
The effects of volatile anesthetics on active (ventricular relaxation) and passive (chamber stiffness) indices of diastolic function and on left ventricular filling rates in dogs were studied to determine how these agents affect left ventricular diastolic performance. Thirty-five mongrel dogs were randomly assigned to receive sevoflurane, isoflurane, enflurane, or halothane. Left ventricular pressure waveforms, phonocardiograms, and echocardiograms were recorded after administering the anesthetics at concentrations of 0% (control), 1%, 2%, and 3%. Ventricular relaxation was defined as the time constant of the decline in left ventricular pressure. Chamber stiffness was derived from the ventricular pressure-volume relationship during passive filling. Rapid filling rate, slow filling rate, and atrial filling rate were obtained from echocardiograms and phonocardiograms. No change in the time constant or in chamber stiffness was observed at any concentration of sevoflurane or isoflurane. However, the highest studied concentration of enflurane and halothane produced a significant increase in the time constant and in chamber stiffness. Rapid filling rate as well as atrial filling rate decreased significantly with the volatile anesthetics, especially with enflurane and halothane. Sevoflurane and isoflurane did not alter ventricular relaxation or chamber stiffness, but did affect diastolic function as manifested by their alteration of filling rates. In contrast, enflurane and halothane each prolonged ventricular relaxation and increased chamber stiffness. With the administration of the volatile anesthetics, the rapid filling rate decreased with the deterioration of diastolic function; in addition, atrial filling rates decreased and did not compensate for the reduction in early ventricular filling. 相似文献
998.
The present study examined the effects of pre-entry experiences (i.e. career maturity), as well as support networks (i.e. informational and friendship), on newcomers' mental health (i.e. depression, self-esteem, psychosomatic symptoms, and work motivation). We performed a longitudinal study of 890 men and women who first entered the workplace in 2003. Surveys were distributed at two time points: just prior to entering the workplace, and two months after entering. Results indicated that career maturity related positively to newcomers' mental health, and newcomers with high career maturity were more successful in establishing positive relationships with superiors and co-workers. Although, informational support networks positively related to work motivation, friendship networks did not show any direct effects on mental health. These results underscore the crucial roles of career maturity and informational networks in facilitating the transition to the workplace. The results also provide empirical support for an expanded view of the importance of pre-entry experiences to workplace newcomers' mental health. 相似文献
999.
Mizuno S Ito H Hamajima N Tamakoshi A Hirose K Tajima K 《Journal of epidemiology / Japan Epidemiological Association》2004,14(3):94-99
BACKGROUND: Genetic polymorphisms have proposed a new insight in smoking behavior. Genes in serotonin system are one of the candidates because of serotonin's role in mood regulation. A polymorphism C218A in intron 7 of the tryptophan hydroxylase (TPH) gene has been hypothesized in relation to smoking predisposition. METHODS: We examined the association on two Japanese populations: one was from the first-visit outpatients of Aichi Cancer Center Hospital during 3-month period between April and June, 2001 (N=591), and the second was from the examinees who attended a health checkup program supported by the Nagoya municipal government in 2000 (N=446). Written documents on informed consent were obtained and lifestyle questionnaires were recorded. TPH C218A genotypes were determined by the polymerase chain reaction with confronting two-pair primers (PCR-CTPP) method. RESULTS: The frequencies of the C- and A-allele were 52% and 48%, respectively, which was in Hardy-Weinberg equilibrium. As for current smoking status, no associations were statistically observed. It was, however, indicated that smokers with A/A genotype started smoking earlier in their life. Among male health examinees, mean ages at starting smoking were 18.7 (A/A), 19.9 (C/A), and 22.4 years (C/C), (P<0.01). Also, on the Aichi Cancer Center Hospital subjects aged 60 and older, mean ages were 19.0 (A/A), 20.2 (C/A), and 20.3 years (C/C) for males and 22.3 (A/A), 31.0 (C/A), and 33.0 years (C/C) for females (P<0.05). CONCLUSIONS: The present study demonstrated that the TPH C218A polymorphism in intron 7 had no association with current smoking status in Japanese population. The hypothesis of early smoking initiation of A/A genotype was partially in agreement. 相似文献
1000.
Bing Wang Kaoru Tanaka Takanori Katsube Yasuharu Ninomiya Guillaume Vares Qiang Liu Akinori Morita Tetsuo Nakajima Mitsuru Nenoi 《Journal of radiation research》2015,56(5):760-767
Both radiation and stresses cause detrimental effects on humans. Besides possible health effects resulting directly from radiation exposure, the nuclear plant accident is a cause of social psychological stresses. A recent study showed that chronic restraint-induced stresses (CRIS) attenuated Trp53 functions and increased carcinogenesis susceptibility of Trp53-heterozygous mice to total-body X-irradiation (TBXI), having a big impact on the academic world and a sensational effect on the public, especially the residents living in radioactively contaminated areas. It is important to investigate the possible modification effects from CRIS on radiation-induced health consequences in Trp53 wild-type (Trp53wt) animals. Prior to a carcinogenesis study, effects of TBXI on the hematopoietic system under CRIS were investigated in terms of hematological abnormality in the peripheral blood and residual damage in the bone marrow erythrocytes using a mouse restraint model. Five-week-old male Trp53wt C57BL/6J mice were restrained 6 h per day for 28 consecutive days, and TBXI (4 Gy) was given on the 8th day. Results showed that CRIS alone induced a marked decrease in the red blood cell (RBC) and the white blood cell (WBC) count, while TBXI caused significantly lower counts of RBCs, WBCs and blood platelets, and a lower concentration of hemoglobin regardless of CRIS. CRIS alone did not show any significant effect on erythrocyte proliferation and on induction of micronucleated erythrocytes, whereas TBXI markedly inhibited erythrocyte proliferation and induced a significant increase in the incidences of micronucleated erythrocytes, regardless of CRIS. These findings suggest that CRIS does not have a significant impact on radiation-induced detrimental effects on the hematopoietic system in Trp53wt mice. 相似文献