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61.
62.
Akinori Mitsui Midori Yoshizawa Hiromichi Matsumoto Emiko Fukui 《Journal of assisted reproduction and genetics》2009,26(1):35-39
Purpose The effects of reciprocal transplantation of meiosis-II chromosomes between senescent and young mouse oocytes were evaluated
based on pre- and post-implantation development ability of resultant embryos.
Methods Karyoplasts including meiosis-II chromosomes of oocytes from senescent Rockefeller mouse/Ms-Rb(6, 15) females (10 to 12 months,
age-related infertile mice) were transferred into cytoplasts of oocytes from young F1 females (3 to 5 months). Reconstructed oocytes were fertilized in vitro, and then the resultant embryos were cultured in
vitro and transferred to recipient mice.
Results The reconstructed oocytes that consisted of aged-karyoplasts and young-cytoplasts showed significantly improved embryonic
development (from 23.2% to 30.0%) and development to term (from 6.3% to 27.1%, P < 0.05) as compared with the oocytes reconstructed from young-karyoplasts and aged-cytoplasts.
Conclusions The present study showed successful rejuvenation for age-related infertility using transplantation of meiosis-II chromosomes
in animal experimental models.
Capsule Transplantation of meiosis-II chromosomes of senescent mouse oocytes into cytoplasts of young mouse oocytes improves subsequent
embryonic and fetal development until birth. 相似文献
63.
Muraoka A Takeda S Matsui M Shimizu T Tohnai I Akiyama S Nakao A 《Hepato-gastroenterology》2004,51(60):1662-1666
BACKGROUND/AIMS: The anti-cancerous effect on hepatocellular carcinoma of a newly established form of thermotherapy, which uses an implant heating system, was evaluated. As a new material for application in hyperthermia, the authors developed a powder type Mg-ferrite complex that produces heat under a relatively low-power magnetic field. METHODOLOGY: This material suspended in Lipiodol was injected into tumors on the backs of mice that consisted of human hepatocellular carcinoma cells. Hyperthermia was performed by directing a magnetic charge on tumor-bearing mice that contained the Mg-ferrite complex. The temperature of the tumor was kept at 42-43 degrees C, while the magnetic field power ranged from 50 to 80G. RESULTS: A 10-min hyperthermia treatment was insufficiently effective against tumor growth. Systemic injection of doxorubicin (ADM) before hyperthermia appeared to enhance the anti-cancerous effect, but the difference was little and did not reach a statistically significant level (repeated measure analysis of variance). The anticancerous effect of hyperthermia for 15 minutes, in contrast, was marked. The nodules had almost completely disappeared by the end of the experiment. CONCLUSIONS: In conclusion, it is suggested that hyperthermotherapy using this newly developed Mg-ferrite complex might become an option for low-invasive therapy for advanced hepatocellular carcinoma in humans. 相似文献
64.
65.
Kaneki T Kawashima A Akamatsu T Tanaka N Kubo K Koizumi T Sekiguchi M Hosaka N Honda T Koike S Adachi W 《Journal of gastroenterology》1999,34(2):253-259
We report a rare case of immunoblastic lymphadenopathy (IBL)-like T-cell lymphoma complicated by multiple gastrointestinal
involvement, which appeared to be ameliorated by chemotherapy but resulted in perforative peritonitis. A 66-year-old Japanese
woman who had generalized lymphadenopathy and eruptions was admitted to our hospital because of bloody stool. Colonoscopic
examination revealed hemorrhagic ulcers in the terminal ileum and a saucer-like ulcer in the cecum. Gastrointestinal endoscopy
revealed several ulcerative or elevated lesions in stomach and duodenum. Biopsy specimens of these lesions and of a lymph
node showed characteristic histological features of IBL-like T-cell lymphoma. The initial treatment with prednisolone (PSL)
and cyclophosphamide (CPA) was effective. Six months after the treatment, however, she developed bloody stool again caused
by multiple ulcerative lesions in the large intestine. The recurrence of the disease was determined histologically, and four
courses of CPA, PSL, vinblastine sulfate and doxorubicin hydrochloride (CHOP) therapy were administered. One month after completing
the CHOP therapy, she developed intestinal obstruction and then acute peritonitis resulting from perforation at an ulcer scar
in the jejunum. Surgical treatment was successful, and histological examination demonstrated no lymphoma cells in the resected
specimen. A gastrointestinal perforation should be recognized as a potential complication of IBL-like T-cell lymphoma, even
during remission.
(Received: June 24, 1998; accepted: Oct. 23, 1998) 相似文献
66.
BACKGROUND AND OBJECTIVE: Although the pathogenesis of interstitial pneumonia and pulmonary fibrosis are not well understood, it has been reported that inflammatory cells, especially neutrophils, and the injurious substances produced by them play important roles in the progression of interstitial pneumonia and subsequent fibrosis. Erythromycin and other 14-membered ring macrolides (14-MRMLs) have been reported to improve the survival of patients with diffuse panbronchiolitis by antineutrophil and several other anti-inflammatory mechanisms. The present study was undertaken to investigate the effects of 14-MRMLs on an experimental model of bleomycin-induced acute lung injury and subsequent fibrosis in mice. METHODS: Bleomycin was administered IV to ICR mice. At 28 days after bleomycin injection, fibrotic foci were histologically observed in left lung tissues, and hydroxyproline content in right lung tissues was chemically analyzed. The inhibitory effects of 14-MRMLs were assessed by overall comparison between control (normal saline solution [NS] alone), untreated (bleomycin alone), and treated (bleomycin plus 14-MRMLs) groups. For evaluation of early-phase inflammation, cell populations in BAL fluid and induction of messenger RNA (mRNA) of adhesion molecules (E-selectin, P-selectin, intercellular adhesion molecule 1 [ICAM-1], and vascular cell adhesion molecule 1 [VCAM-1]) in lung tissues were examined at 0 to 13 days after bleomycin treatment. These parameters were also compared with those for the control (NS alone), 14-MRML untreated (bleomycin alone), and 14-MRML pretreated (bleomycin plus 14-MRML pretreated) groups. RESULTS: Bleomycin-induced pulmonary fibrosis was inhibited by erythromycin and other 14-MRMLs on day 28 after bleomycin injection in ICR mice, especially those pretreated with 14-MRMLs. Hydroxyproline content in lung tissues was also decreased in the 14-MRML-pretreated groups. The number of neutrophils in BAL fluid significantly increased, with two peaks at 1 day and 9 days (from 6 to 11 days) after bleomycin administration. 14-MRMLs significantly inhibited both peaks of neutrophil infiltration into the airspace. Changes in mRNA expression of adhesion molecules (E-selectin, P-selectin, ICAM-1, VCAM-1) were associated with leukocyte migration into the airspace. 14-MRMLs clearly inhibited the induction of VCAM-1 mRNA, and tended to attenuate that of ICAM-1 mRNA, but inhibited the induction of neither E-selectin mRNA nor P-selectin mRNA. CONCLUSION: These findings indicate that attenuation of inflammatory cell migration into the airspace by 14-MRMLs, especially of neutrophils and macrophages, resulted in inhibition of lung injury and subsequent fibrosis. 14-MRMLs clearly attenuated the expression of VCAM-1 mRNA during the early phase of bleomycin-induced lung injury, and this might be one mechanism of inhibition of neutrophil and macrophage migration into the airspace by 14-MRMLs. This may be one mechanism of the anti-inflammatory and antifibrotic effects of 14-MRMLs. These findings suggest that prophylactic administration of 14-MRMLs may be clinically efficacious in preventing acute exacerbation of interstitial pneumonia and acute lung injury. 相似文献
67.
Aging increases, and duodenal ulcer reduces the risk for intestinal metaplasia of the gastric corpus in Japanese patients with dyspepsia 总被引:2,自引:0,他引:2
Tsukui T Kashiwagi R Sakane M Tabata F Akamatsu T Wada K Futagami S Miyake K Sueoka N Hirakawa T Kobayashi M Fujimori T Sakamoto C 《Journal of gastroenterology and hepatology》2001,16(1):15-21
BACKGROUND AND AIMS: The classification of gastritis by using the revised Sydney system suggests that there are two types of Helicobacter pylori-related gastritis. The aim of the present study was to examine the risk factors that might be involved in the presence of either atrophic gastritis or intestinal metaplasia of the gastric corpus of Japanese patients. METHODS: Biopsy samples were obtained from the gastric corpus in 154 patients with dyspepsia, and the degree of atrophy or intestinal metaplasia was determined histologically. The correlation between several variables and presence of atrophy or intestinal metaplasia was evaluated by using multivariate analysis. RESULTS: Among the 11 variables, which included age, peptic ulcer diseases and H. pylori infection, H. pylori infection was the major risk factor associated with the presence of atrophic gastritis or intestinal metaplasia of the gastric corpus. In contrast, duodenal ulcer (DU) disease reduced the risk of contracting both conditions. Age was an independent risk factor only for intestinal metaplasia of the gastric corpus. When 128 H. pylori-positive subjects were analyzed, DU and age were similarly associated with the presence of both conditions. CONCLUSIONS: These results suggest that DU reduces the risk for contracting atrophic gastritis and intestinal metaplasia, and age is an independent risk factor for intestinal metaplasia of the gastric corpus in dyspeptic Japanese patients. 相似文献
68.
Isolation of a somatic-cell mutant defective in phosphatidylserine biosynthesis. 总被引:1,自引:1,他引:1 下载免费PDF全文
O Kuge M Nishijima Y Akamatsu 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(7):1926-1930
Mutant clones of Chinese hamster ovary (CHO) cells defective in the base-exchange reaction of phospholipids with choline were isolated by using an in situ enzymatic assay for the reaction in cell colonies immobilized on polyester cloth. The specific activities of the choline-exchange reaction in extracts of one of the mutants (designated 64) grown at 33 degrees C and 40 degrees C were 13% and 6% of those in parental (CHO-K1) cells, respectively. The choline-exchange activity in the mutant was more thermolabile in cell extracts than that in the parent, suggesting that a mutation in the structural gene for the choline-exchange enzyme might have been induced in this mutant. In culture medium supplemented with lipoprotein-deficient serum, mutant 64 grew almost normally at 33 degrees C but divided only twice at 40 degrees C and then stopped growing. Labeling of intact cells with [32P]Pi showed that mutant 64 was also strikingly defective in the biosynthesis of phosphatidylserine at 40 degrees C but was normal at 33 degrees C. Most temperature-resistant revertants of mutant 64 exhibited nearly normal ability to synthesize phosphatidylserine at 40 degrees C and also showed choline-exchange activity similar to that in parental cells. The addition of phosphatidylserine to medium supplemented with newborn calf serum, in which mutant 64 grew more slowly than parental cells at 40 degrees C, restored the growth rate of the mutant to the parental level. Our findings suggest that the choline-exchange enzyme functions as the major route for the formation of phosphatidylserine and that the temperature-sensitive growth of mutant 64 is due to a defect in phosphatidylserine biosynthesis at 40 degrees C. 相似文献
69.
Teruo Nakamura Tadashi Takeuchi Akinori Terada Yusuke Tando Toshihiro Suda 《Journal of gastrointestinal cancer》1998,23(2):137-143
Summary
Conclusion. Near-infrared spectrometry is a new, rapid, and accurate method for measuring fecal fat that does not require
a great deal of chemical knowledge and that can be used by anyone. This method is considered indispensable for the diagnosis
of pancreatic steatorrhea and treatment follow-up.
Methods. Fecal fats (GLC method, van de Kamer method), neutral sterols (GLC method), bile acids (GLC method) and short-chain fatty
acids (HPLC method) were assayed by the respective conventional methods in 120 subjects, including patients with pancreatic
dysfunction, and the results were compared with the those obtained by near-infrared spectrometry. The correlations between
fecal fat excretion measured by the GLC method (x) and van de Kamer method (x) and by near-infrared spectrometry (y) were expressed by y=1.10 x-0.16 (r=0.949, P<0.01) and y=0.750x+1.654 (r=0.930, p<0.01), respectively.
Results. The sensitivity and specificity of near-infrared spectrometry for fecal fats were 94.9 and 98.2%, respectively, when compared
with the GLC method, and 87.5 and 90.0%, respectively, when compared with the van de Kamer method. In contrast, near-infrared
spectrometry was not nearly as accurate as the conventional methods for determining neutral sterols, bile acids, and short-chain
fatty acids. 相似文献
70.
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