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61.
Tetsuya Kawashima Yoshiyuki Yokota Mitsuhiro Yokoyama Hiroshi Itoh 《Pathology international》1993,43(6):304-312
The pathomorphologic features of hypertrophic cardiomyopathy simulating dilated cardiomyopathy in the late stage (HCM-DCM) were compared with those of ordinary hypertrophic cardiomyopathy (HCM). Seven autopsied hearts with HCM-DCM and 11 with HCM were assessed quantitatively using an image analyzer. Unlike HCM, significant left ventricular enlargement and wall thinning were observed in HCM-DCM, and the percentage areas of massive fibrosis and disarray were significantly greater. In HCM-DCM, the disarray was distributed diffusely, whereas massive fibrosis was distributed more intensively in the ventricular septum and anterior wall than in the lateral and posterior wall. Narrowing of intramyocardial small arteries was observed more frequently in HCM-DCM, especially in the ventricular septum and anterior wall, than in HCM. These results suggest that the enlargement and wall thinning of the left ventricle in HCM-DCM are attributable to non-uniform progression of massive fibrosis, which is closely related to small-arterial lesions. 相似文献
62.
Unique properties of fetal lymphoid progenitors identified according to RAG1 gene expression 总被引:3,自引:0,他引:3
Yokota T Kouro T Hirose J Igarashi H Garrett KP Gregory SC Sakaguchi N Owen JJ Kincade PW 《Immunity》2003,19(3):365-375
RAG1/GFP knockin mice were exploited to isolate and characterize fetal lymphoid progenitors. CD11b and IL-7Ralpha are expressed in a developmental stage-dependent fashion, revealing how substantial numbers of early lymphoid progenitors were discarded or neglected in previous studies. The myeloerythroid potential of fetal progenitors in clonal assays declined in synchrony with activation of the RAG1 locus but was not completely extinguished. Lymphoid differentiation corresponded to patterns of gene expression previously found for adult marrow, but no fraction of fetal liver was enriched with respect to B + T progenitors. Also, unlike adults, fetal lymphoid progenitors transiently expressed endothelial cell markers. These findings help to reconcile discrepancies in previous reports and suggest that the fetal immune system arises via unique mechanisms. 相似文献
63.
Alterations in the INK4a/ARF locus and their effects on the growth of human osteosarcoma cell lines 总被引:4,自引:0,他引:4
Park YB Park MJ Kimura K Shimizu K Lee SH Yokota J 《Cancer Genetics and Cytogenetics》2002,133(2):105-111
Two different proteins, p16(INK4a) and p14(ARF), encoded by the INK4a/ARF locus play important roles in the RB and p53 pathways, respectively. This study was performed to determine genetic and epigenetic alterations in the INK4a/ARF locus and their effects on the growth of osteosarcoma. Among six cell lines examined, both p16(INK4a) and p14(ARF) exons were homozygously deleted in two cell lines, MG63 and HOS, and both p16(INK4a) and p14(ARF) promoters were methylated in one cell line, U2OS. Wild-type mRNA and proteins for p16(INK4a) and p14(ARF) were expressed in three other cell lines, SaOS2, HuO9, and G292. Transfection studies were performed using two cell lines, U2OS and MG63. Both the RB and p53 genes were wild types in U2OS, whereas p53 but not RB was mutated in MG63. Both p16(INK4a) and p14(ARF) suppressed the growth of U2OS, whereas p16(INK4a) but not p14(ARF) suppressed the growth of MG63. p53 only did not suppress the growth of MG63 either; however, coexpression of p14(ARF) with p53 increased the fraction of the G0/G1 phase in MG63 cells. The data presented here demonstrate the importance of genetic and epigenetic alterations in the INK4a/ARF locus for the growth of osteosarcoma and thus will be useful to further understand the biologic behavior of osteosarcoma in association with the defects in the p53 and RB pathways. 相似文献
64.
Takahashi K Nishiyama C Nishiyama M Okumura K Ra C Ohtake Y Yokota T 《European journal of immunology》2001,31(2):590-599
The high-affinity IgE receptor, FcepsilonRI, is a key regulatory molecule in the allergic reaction. During the course of studies to find cis-acting elements for FcepsilonRI alpha chain gene expression, a CAGCTG sequence located in the first intron was revealed to serve as a crucial enhancer element. Electromobility shift assays using antibodies and in vitro translation products showed that the CAGCTG element was recognized by the USF1/USF2 complex. As was the case for other intronic cis-elements, the CAGCTG element regulated the promoter in an orientation- and position-dependent manner. Overexpression of USF2 antisense repressed the FcepsilonRI alpha chain gene promoter and decreased the amount of alpha chain mRNA in mast cell lines. All these results indicated that the USF1/USF2 complex activates the human FcepsilonRI alpha chain gene expression via the CAGCTG element in the first intron. 相似文献
65.
Toyoji Kakuchi Toshiyuki Hasegawa Hiroshi Sasaki Hiroshi Ohmori Kazumi Yamaguchi Kazuaki Yokota 《Macromolecular chemistry and physics.》1989,190(9):2091-2097
Chiral poly(crown ether)s were synthesized by cationic cyclopolymerization of (S)-2,2′-bis(2-vinyloxyethoxy)-3,3′-dimethyl-1,1′-binaphthyl [(S)- 1b ] and (R)-2,2′-bis[2-(2-vinyloxyethoxy)-ethoxy]-3,3′-dimethyl (or 3,3′-diphenyl)-1,1′-binaphthyl [(R)- 3b or (R)- 3c ]. The substituents in the 3,3′-positions of binaphthyl moiety disturb the intramolecular cyclization in the polymerization of monomer (S)- 1b , but have no influence on the cyclopolymerization tendency of monomers (R)- 3b and (R)- 3c . The polymers from (R)- 3b and (R)- 3c [(R)- 4b and (R)- 4c ] have a higher ability of chiral recognition towards a-amino acids, such as phenylglycine, phenylalanine, valine, and methionine, than the polymer from (R)- 3a [(R)- 4a ], which has no substituent in 3,3′-positions. The methyl and the phenyl substituents in the 3,3′-positions undoubtedly act as additional barrier causing an increase in the ability of chiral recognition, though the effect is less than expected from the result of model crown ethers. 相似文献
66.
The anatomical relationship between the kidney position and its arterial supply was investigated in 21 mammals, 1 bird, and 3 reptiles (n = 1 for each species) and in 43 human cadavers. The following observations were made. (1) Although the right kidney was located caudal to the left kidney in 29 out of 43 human cadavers (67.4%), the origin of the right renal artery from the aorta was located cranial to the origin of the left renal artery in 36 human cadavers (83.7%). Therefore, the relative positions of the kidneys do not correspond with the relative origins of the renal arteries in humans. (2) Among the mammals that were examined, the position of the kidney and the branching level of the renal artery on the right side were usually cranial to those on the left side. (3) In the bird and most reptiles that were examined, kidneys were typically located in the pelvic region and were supplied by segmental arterial branches. These results suggest that the right kidney and its arterial supply are generally located cranial to the left kidney in phylogeny of mammals. While the presence of a human accessory renal artery in 9 out of 86 sides (10.5%) and a cranial origin of the left renal artery relative to the right renal artery in 7 out of 43 cadavers (16.3%), shows some variation in the arterial supply to the kidneys, the origin of the renal arteries can generally be used as phylogenetic landmarks indicating the relative positions of the kidneys. Hence, from an ontological perspective, the human right kidney may be initially situated cranial to the left kidney during the early stages of development. Thereafter, the human right kidney may shift downwards secondary. 相似文献
67.
K Yokota Y Kato N Kobayashi M Fujikawa H Nishimura O Akazawa T Ebara Z Ishii Y Hiki 《Gan to kagaku ryoho. Cancer & chemotherapy》1986,13(11):3256-3260
The patient was a 65-year-old male who came to our hospital with a complaint of dysphagia. He was admitted to hospital following a diagnosis of combined tumor in the esophagus and stomach as revealed by X-ray fluoroscopy. For preoperative chemotherapy, he was given oral administration of BLM-polyacrylate pasta, 30 mg/day for 25 days and 15 mg/day for 5 days, up to a total dose of 825 mg. This regimen successfully reduced the tumor in the esophageal area. No signs of pulmonary dysfunction, changes in blood cell count and blood chemistry of any other abnormalities in his general status were seen as side-effects of the BLM-polyacrylate pasta. Thoracic-esophagectomy and total gastrectomy were performed on November 7, 1983. He has been maintaining a good quality of life without any signs of recurrence of the tumor for the last two years and six months after the operation. The esophageal tumor was identified as moderately differentiated squamous cell carcinoma with A0N0M0Pl0 and grade of invasion "mp", while the gastric tumor was moderately differentiated adenocarcinoma with H0P0S0N0 and invasion grade "m" in the early stage of IIa + IIc type. 相似文献
68.
Koichi Yasuda Hideki Minatogawa Yasuhiro Dekura Seishin Takao Masaya Tamura Nayuta Tsushima Takayoshi Suzuki Satoshi Kano Takatsugu Mizumachi Takashi Mori Kentaro Nishioka Motoyasu Shido Norio Katoh Hiroshi Taguchi Noriyuki Fujima Rikiya Onimaru Isao Yokota Keiji Kobashi Shinichi Shimizu Akihiro Homma Hiroki Shirato Hidefumi Aoyama 《Journal of radiation research》2021,62(2):329
Pharyngeal cancer patients treated with intensity-modulated proton therapy (IMPT) using a model-based approach were retrospectively reviewed, and acute toxicities were analyzed. From June 2016 to March 2019, 15 pharyngeal (7 naso-, 5 oro- and 3 hypo-pharyngeal) cancer patients received IMPT with robust optimization. Simulation plans for IMPT and intensity-modulated X-ray therapy (IMXT) were generated before treatment. We also reviewed 127 pharyngeal cancer patients with IMXT in the same treatment period. In the simulation planning comparison, all of the normal-tissue complication probability values for dysphagia, dysgeusia, tube-feeding dependence and xerostomia were lower for IMPT than for IMXT in the 15 patients. After completing IMPT, 13 patients completed the evaluation, and 12 of these patients had a complete response. The proportions of patients who experienced grade 2 or worse acute toxicities in the IMPT and IMXT cohorts were 21.4 and 56.5% for dysphagia (P < 0.05), 46.7 and 76.3% for dysgeusia (P < 0.05), 73.3 and 62.8% for xerostomia (P = 0.43), 73.3 and 90.6% for mucositis (P = 0.08) and 66.7 and 76.4% for dermatitis (P = 0.42), respectively. Multivariate analysis revealed that IMPT was independently associated with a lower rate of grade 2 or worse dysphagia and dysgeusia. After propensity score matching, 12 pairs of IMPT and IMXT patients were selected. Dysphagia was also statistically lower in IMPT than in IMXT (P < 0.05). IMPT using a model-based approach may have clinical benefits for acute dysphagia. 相似文献
69.
Assay method for Vibrio cholerae and Escherichia coli enterotoxins by automated counting of floating chinese hamster ovary cells in culture medium. 下载免费PDF全文
As Chinese hamster ovary (CHO) cells on plastic proliferate, many cells float off into the medium instead of piling up after they form a monolayer. Fewer cells were floating in the medium when CHO cells were incubated with cholera toxin at a concentration as low as 10 pg/ml. The toxin increased the adhesiveness of the cells forming confluent monolayers so that the floating cells accumulated on the adherent monolayers. On the basis of this finding, a simple, quantitative assay method for cholera and Escherichia coli enterotoxins was devised by cultivating CHO cells in a Linbro multidish and counting the cells in the medium with a Coulter Counter. The method was sensitive enough to detect toxins in 100- to 200-fold-diluted culture media of toxigenic E. coli strains. Little or no activity was detected by this method in the culture medium of nontoxigenic E. coli. 相似文献
70.
Fundal atrophic gastritis and Helicobacter pylori have been implicated as possible etiologic factors in gastric cancer. This case-control study was performed to determine which risk factor is more closely related to gastric cancer. The endoscopic Congo red test was performed to evaluate the extent of fundal atrophic gastritis in 43 patients with gastric cancer and 86 cancer-free control subjects, who were individually matched by age, sex, and date of endoscopy (within 3 months). The prevalance of H. pylori infection and severe fundal gastritis were significantly higher in patients with differentiated adenocarcinoma, but not with undifferentiated adenocarcinoma, than in control subjects. The odds ratios for differentiated and undifferentiated adenocarcinomas were 6.85 (95% confidence interval, 1.94-11.82) and 1.50 (95% CI, 0.84-3.11), respectively. However, the odds ratio of H. pylori infection was greater than that of severe fundal gastritis. Moreover, multivariate analysis provided similar results. H. pylori infection is an independent indicator of a higher risk of the differentiated adenocarcinomas of the stomach than is severe fundal gastritis. 相似文献