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31.
Momose-Sato Yoko; Sato Katsushige; Hirota Akihiko; Kamino Kohtaro 《Journal of neurophysiology》1998,79(4):2208-2217
32.
Oda Y Funasaka K Kitano M Nakama A Yoshikura T 《Environmental and molecular mutagenesis》2004,43(1):10-19
In the present study, we developed a rapid umu-microplate test system that uses the nitroreductase- and O-acetyltransferase-overproducing Salmonella typhimurium strain NM3009 and the O-acetyltransferase-overproducing S. typhimurium strain NM2009 to detect genotoxic activity in small volume samples. The assay was used to test the genotoxicity of several standard mutagens and environmental samples. Exponentially growing cultures of NM3009, NM2009, and the parental strain TA1535/pSK1002 were incubated in 96-well microplates with test chemicals both in the presence and in the absence of rat liver S9. The relative beta-galactosidase activities were then determined colorimetrically using either chlorophenol red-beta-D-galactopyranoside (CPRG) or O-nitrophenyl-beta-D-galactopyranoside (ONPG) as a measure of umuC gene induction activity. The sensitivities of NM3009 without S9 mix and NM2009 with S9 mix to nitroarenes and aromatic amines were up to 24- to 75-fold higher than those of the parent strain. Induction of umuC gene expression was detected more readily with CPRG than ONPG. The umu-microplate assay also detected genotoxicity in organic extracts of particulate matter from air samples collected in Osaka City, Japan. The pattern of the responses suggested that the genotoxic activity of the particulate extract was due primarily to nitrated polycyclic aromatic hydrocarbons. Our results indicate that the umu-microplate assay may be a useful way of carrying out rapid screens for genotoxicity in small-volume environmental samples. 相似文献
33.
Fukuda T Nogami S Ohya Y 《Genes to cells : devoted to molecular & cellular mechanisms》2003,8(7):587-602
BACKGROUND: Inteins and group I introns found in prokaryotic and eukaryotic organisms occasionally behave as mobile genetic elements. During meiosis of the yeast Saccharomyces cerevisiae, the site-specific endonuclease encoded by VMA1 intein, VDE, triggers a single double-strand break (DSB) at an inteinless allele, leading to VMA1 intein homing. Besides the accumulating information on the in vitro activity of VDE, very little has been known about the molecular mechanism of intein homing in yeast nucleus. RESULTS: We developed an assay to detect the product of VMA1 intein homing in yeast genome. We analysed mutant phenotypes of RecA homologs, Rad51p and Dmc1p, and their interacting proteins, Rad54p and Tid1p, and found that they all play critical roles in intein inheritance. The absence of DSB end processing proteins, Sae2p and those in the Mre11-Rad50-Xrs2 complex, also causes partial reduction in homing efficiency. As with meiotic recombination, crossover events are frequently observed during intein homing. We also observed that the absence of premeiotic DNA replication caused by hydroxyurea (HU) or clb5delta clb6delta mutation reduces VDE-mediated DSBs. CONCLUSION: The repairing system working in intein homing shares molecular machinery with meiotic recombination induced by Spo11p. Moreover, like Spo11p-induced DNA cleavage, premeiotic DNA replication is a prerequisite for a VDE-induced DSB. VMA1 intein thus utilizes several host factors involved in meiotic and recombinational processes to spread its genetic information and guarantee its progeny through establishment of a parasitic relationship with the organism. 相似文献
34.
Pheochromocytoma without specific symptoms 总被引:1,自引:0,他引:1
35.
36.
Machine oils are widely used in metal processing and many workers are exposed to oil mists in the work environment. Some investigators have pointed out such health hazards due to prolonged exposure to oil mist as respiratory disorders, dermatitis, and possible carcinogenesis. In Japan, a permissible limit of oil mists of 3 mg/m3 was recommended in 1977 by the Japan Association of Industrial Health (JAIH) mainly based on the hazardous effects on the respiratory system. After this recommendation was made, only a few studies have been made on the measurement of oil mists and on the health effects in machine workers to determine whether the permissible limit is justifiable or not. In the present study, the levels of oil mists in the air of machine workshops were measured together with personal exposure levels by personal samplers. Oil mists were collected by a sampler head with 2 stages which enabled differentiation of distribution of particulates between larger than 10 microns and 2-10 microns in size. Oil components collected on the stainless steel stages were washed out by sonication in CCl4 solution and measured by an oil meter with infra-red spectrometry against a standard solution of heavy oil class B according to procedures reported elsewhere by the authors. Questionnaire surveys were also conducted on 308 male machine workers composed of 221 workers exposed to oil mists and 87 nonexposed controls. The questions were composed of five items about air quality in the work environment and 18 subjective symptoms during work and daily lives. The symptoms included nasopharyngeal, muco-dermal, gastrointestinal and neuro-muscular symptoms. Statistical analysis was made by the Manthel-Haenszel method for a comparison of "yes" rates of complaints between the exposed and the non-exposed by adjusting the underlying confounding factor of age distribution. 1. The levels of oil mists measured here ranged from 94 to 813 micrograms/m3 in the ambient air and from 107 to 483 micrograms/m3 of personal exposure. There was no obvious difference between the level in the ambient air and that of personal exposure. All these measured levels were under the permissible limit (3 mg/m3) recommended by JAIH in 1977. 2. The observed distribution of particulate size of oil mists from 2 to 10 microns referred to as respirable size was 32.8 +/- 16.1% generated from the grinding machines using water-soluble type of machine oils and 50.0 +/- 12.4% from those using insoluble type.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
37.
Thirty-two patients with advanced breast cancer refractory to combination chemotherapy with cyclophosphamide (CPA), doxorubicin
(ADR) and 5-fluorouracil (5-FU) (CAF) were treated with the combination of mitomycin C, etoposide, doxifluridine and medroxyprogesterone
acetate as second line therapy. Observed responses included 6 patients (18.7%) with complete response (CR) and 7 (21.9%) with
partial response (PR). Two (50%) out of 4 patients who had bone pain due to bone metastasis noted pain relief. CR or PR were
obtained in 4 out of 12 patients who had not responded to the previous CAF therapy. While grade III myelosuppression was observed
in 3 patients, other adverse effects were minimal. It is suggested that this combination therapy may be recommended for advanced
breast cancer patients as a second therapy. 相似文献
38.
Tomoaki Yuhi Akihiko Wada Ryuichi Yamamoto Masanobu Urabe Hiromi Niina Futoshi Izumi Toshihiko Yanagital 《Naunyn-Schmiedeberg's archives of pharmacology》1994,350(2):209-212
We have previously reported that in bovine adrenal chromaffin cells Ptychodiscus brevis toxin-3 (PbTx-3) does not alter the veratridine-induced 22Na influx when given alone, but increases the influx of 22Na when co-applied with either - or -scorpion venom (Wada et al. 1992). In the present study, we characterized [3H]PbTx-3 binding in bovine adrenal chromaffin cells. [3H]PbTx-3 binding was saturable, reversible and of high-affinity with an equilibrium dissociation constant (Kd) of 32.0±4.9 nmol/1 and a maximum binding capacity Bmax of 6.2 ± 1.2 pmol/4 × 106 cells (4.5 ± 0.9 pmol/mg cell protein). A Hill plot revealed the lack of cooperative interaction among the binding sites. Unlabelled PbTx-3 inhibited [3H]PbTx-3 binding with an IC50 of 31 nmol/l. However, tetrodotoxin, veratridine, - and -scorpion venom, or veratridine in combination with either - or -scorpion venom did not alter [3H]PbTx-3 binding. All these results suggest that PbTx-3 binds to a site (site 5) distinct from the previously known four toxin binding sites, which does not gate voltage-dependent Na channels by itself, but is specifically involved in the allosteric modulation of Na channels in adrenal medullary cells.
Correspondence to: A. Wada at the above address 相似文献
39.
Obayashi T Kaneko T Nogami A Naito S Iijima T Murai N Aizaki M 《Kyobu geka. The Japanese journal of thoracic surgery》1999,52(3):229-233
A 74-year-old woman admitted with exertional dyspnea. Echocardiography revealed the giant left ventricular aneurysm. In the hospital course, she fell into sustained monomorphic ventricular tachycardia. Coronary angiogram showed complete obstruction of the LAD. Left ventricular ejection fraction was 20%. The origin of tachycardia seems to be at infero-apicallateral area of LV by electrophysiology study. Because of the failure of RF energy ablation, we planned mapping-guided cryoablation, CABG and endoaneurysmorrhaphy. To prevent air embolism and myocardial ischemic damage for long aortic cross clamp, intraoperative endocardial mapping was carried out on beating heart due to continuous normothermic coronary blood perfusion (300 ml/min) from the aortic root cannula under aortic clamping. Cold crystalloid cardioplegia changed into the root cannula after EPS, focal cryoablation (-100 degrees C) was performed 3 times on cardiac arrest. Sustained VT was not inducible in the following study. CABG and endoaneurysmorrhaphy was performed on repeated cardiac arrest during single aortic clamp. Postoperative course was uneventful, and she discharged 8 weeks after the operation. 相似文献
40.
Kuba H Sato N Uchiyama A Nakafusa Y Mibu R Yoshida K Kuroiwa K Tanaka M 《Surgery today》1999,29(4):375-377
We herein describe a patient with mediastinal lymph node metastases which occurred after both a primary sigmoid colon cancer
and metachronous ovarian metastasis had been resected. The most likely route of metastases to the mediastinum in this case
is the paravertebral venous plexus probably connected to the ovarian metastasis, or so-called remetastasis. This case illustrates
that the mediastinum is thus a possible metastatic site in patients with colon cancer. Surgeons should therefore pay attention
to the mediastinum as well as the lung fields when checking chest X-ray films during a follow-up of patients after a resection
of colon cancer. 相似文献