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991.
Diverse p53 gene aberration in hepatocellular carcinoma detected by dual-color fluorescence in situ hybridization 总被引:3,自引:0,他引:3
Kondo M Marusawa H Ueda Y Katsurada A Kawasome C Takami S Kinoshita M Ikai I Yamaoka Y Chiba T 《Journal of gastroenterology and hepatology》2004,19(9):1066-1073
BACKGROUND AND AIM: In order to evaluate loss of the p53 gene more precisely, we performed dual-color fluorescence in situ hybridization (dual-color FISH) for chromosome 17 and p53 gene together with DNA polymorphism analysis of the p53 gene in hepatocellular carcinoma (HCC). METHODS: Dual-color FISH using probes specific for the centromere of chromosome 17 and the p53 gene was performed for 41 HCC and DNA polymorphism analysis was also performed for them. RESULTS: Of the 34 HCC tested by dual-color FISH, 20 had loss of at least one p53 gene (58.8%). In contrast, of the 32 HCC tested by DNA polymorphism analysis, 23 gave informative results, among which only eight had loss of heterozygosity (LOH) of the p53 gene (34.8%). Notably, among 14 cases positive for loss of the p53 gene by dual-color FISH, seven cases were negative for LOH of the p53 gene. Moreover, dual-color FISH revealed that the percentage of cells that lost at least one p53 gene increased as the HCC became less differentiated (P < 0.01), whereas LOH did not reveal any such correlation. CONCLUSIONS: These data suggest that loss of the p53 gene was present in a considerable number of HCC, and diversity of the p53 gene aberration increases with progression of HCC. Dual-color FISH is an effective method for detection of p53 gene aberration, and it can provide new insight into oncogenesis in HCC. 相似文献
992.
Targeted gene expression without a tissue-specific promoter: Creating mosaic embryos using laser-induced single-cell heat shock
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Marc S. Halfon Hiroyuki Kose Akira Chiba Haig Keshishian 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(12):6255-6260
We have developed a method to target gene expression in the Drosophila embryo to a specific cell without having a promoter that directs expression in that particular cell. Using a digitally enhanced imaging system to identify single cells within the living embryo, we apply a heat shock to each cell individually by using a laser microbeam. A 1- to 2-min laser treatment is sufficient to induce a heat-shock response but is not lethal to the heat-shocked cells. Induction of heat shock was measured in a variety of cell types, including neurons and somatic muscles, by the expression of β-galactosidase from an hsp26-lacZ reporter construct or by expression of a UAS target gene after induction of hsGAL4. We discuss the applicability of this technique to ectopic gene expression studies, lineage tracing, gene inactivation studies, and studies of cells in vitro. Laser heat shock is a versatile technique that can be adapted for use in a variety of research organisms and is useful for any studies in which it is desirable to express a given gene in only a distinct cell or clone of cells, either transiently or constitutively, at a time point of choice. 相似文献
993.
Ikematsu H Nabeshima A Yong C Li W Kajiyama W Hara H Hayashi J Kashiwagi S 《Kansenshōgaku zasshi. The Journal of the Japanese Association for Infectious Diseases》2000,74(5):476-480
An outbreak of an influenza like illness was found in a nursing home in Fukuoka in January, 1999. Results of hemagglutinin inhibition tests with paired sera of patients and rapid diagnosis kit for influenza A indicated that an influenza A (H3N2) outbreak had occurred. A total of 15 patients with influenza like illness from one residential area of the nursing home were administered amantadine, 100 mg per day for five days. Clinical records of 264 residents were surveyed retrospectively from the tenth to the thirty-first of January, 1999. Influenza like illness was found in 112 residents (42.4%). The incidence of influenza like illness differed by residential area, ranging from 27.6% to 54.0%. The mean duration of fever was 3.6 days among patients administered amantadine. The mean duration was 4.4 days for patients not administered amantadine. The incidence of influenza like illness decreased rapidly after amantadine administration in the residential area where amantadine administration was done. These results suggest that amantadine is effective in mitigating influenza symptoms in the elderly. Amantadine may be useful for diminishing the influence of influenza A outbreaks in nursing homes. 相似文献
994.
Hirozumi Sawai Akira Yasuda Nobuo Ochi Jiachi Ma Yoichi Matsuo Takehiro Wakasugi Hiroki Takahashi Hitoshi Funahashi Mikinori Sato Hiromitsu Takeyama 《BMC gastroenterology》2008,8(1):56
Background
The tumour suppressor phosphatase and tensin homolog (PTEN) is an important negative regulator of cell-survival signaling. To evaluate the correlation between PTEN expression and clinicopathological characteristics of colorectal cancer patients with and without liver metastases, we investigated PTEN expression in primary colorectal cancer and colorectal cancer liver metastases. 相似文献995.
New tumor necrosis factor-α-inducing protein released from<Emphasis Type="Italic"> Helicobacter pylori</Emphasis> for gastric cancer progression 总被引:2,自引:0,他引:2
Suganuma M Kurusu M Suzuki K Nishizono A Murakami K Fujioka T Fujiki H 《Journal of cancer research and clinical oncology》2005,131(5):305-313
Purpose To investigate the association between Helicobacter pylori infection and its inflammatory reaction in gastritis, gastric ulcer, and gastric cancer, a new tumor necrosis factor- (TNF-)-inducing protein of H. pylori was studied.Methods The HP0596 gene of H. pylori was identified as the TNF--inducing protein (Tip) gene from genome sequence of H. pylori strain 26695. Using recombinant Tip (rTip) and deleted Tip (rdel-Tip) proteins, the latter of which lacks six amino acids containing two cysteines in the N-terminal domain, we examined their activities in TNF- gene expression and NF-B activation in both Bhas 42 (v-H-ras transfected BALB/3T3) cells and mouse gastric epithelial cell line MGT-40, and in vitro transformation of Bhas 42 cells.Results Tip protein as a homodimer form (38 kDa) was found in both extracts and culture medium of various H. pylori strains. rTip significantly induced TNF- gene expression and NF-B activation in both Bhas 42 cells and MGT-40, and induced in vitro transformation of Bhas 42 cells. However, rdel-Tip did not. Treatment with MG-132, a proteasome inhibitor, inhibited translocation of NF-B p65, and abrogated TNF- induction induced by Tip protein.Conclusion Tip is a new carcinogenic factor released from H. pylori mediated through NF-B activation. 相似文献
996.
Molecular mimicry of mitochondrial and nuclear autoantigens in primary biliary cirrhosis 总被引:2,自引:0,他引:2
Shimoda S Nakamura M Ishibashi H Kawano A Kamihira T Sakamoto N Matsushita S Tanaka A Worman HJ Gershwin ME Harada M 《Gastroenterology》2003,124(7):1915-1925
BACKGROUND & AIMS: The mechanism for development of primary biliary cirrhosis (PBC) remains enigmatic, but molecular mimicry has been implicated because of well-known cross-reactivity of human mitochondrial autoantigens and equivalent bacterial antigens. Virtually all patients with PBC have antimitochondrial autoantibodies (AMA), but, interestingly, approximately 50% also manifest antinuclear antibodies (ANA). METHODS: To determine whether generation of ANA are due to molecular mimicry of mitochondrial peptides, we established 6 T-cell clones selected by a peptide corresponding to the E2 subunit of mitochondrial pyruvate dehydrogenase complex and analyzed for reactivity to mimicry peptides derived from mitochondrial and nuclear autoantigens, including control sequences. RESULTS: For mitochondrial autoantigens, 1 peptide from the E2 subunit of the pyruvate dehydrogenase complex, 1 peptide from the E2 subunit of the oxo-glutarate dehydrogenase complex, 1 peptide from the E2 subunit of the branched-chain 2-oxoacid dehydrogenase complex, and 1 peptide from the E3-binding protein cross-reacted with these T-cell clones. For the nuclear autoantigens, 5 peptides from gp210 and 1 from Sp100 cross-reacted with these clones. Furthermore, 1 of 3 T-cell clones selected by recombinant gp210 protein reacted with a mimicry peptide corresponding to amino acids 188-201 of gp210, indicating that this part of the protein is a naturally processed immunodominant T-cell epitope. CONCLUSIONS: These results demonstrate molecular mimicry between mitochondrial and nuclear autoantigens in PBC and that a mimicry peptide may become an immunodominant T-cell epitope. These data have significance not only for PBC but also for the production of ANA in other disease processes. 相似文献
997.
Masahide Arita M.D. Mitsuo Okada M.D. Akira Motomura M.D. Toshiyuki Matsui M.D. Kiyomi Hosiko M.D. Tsuneyoshi Yao M.D. 《The American journal of gastroenterology》1994,89(2):214-219
The effects of single morning and single bedtime doses of famotidine on intragastric acidity were studied by 24-b intragastric pH monitoring in 16 patients with gastric ulcer. The patients were randomly allocated to tbe following regimen: one group (n = 8) received 40 mg famotidine at 8:30 AM and anotber group (n = 8) received tbo same dose at 10 PM. Tbe morning group showed significant inbibition of gastric acidity during the 24-b and daytime measurements, compared to those of the bedtime group (p < 0.05 in 24 h, p < 0.01 in daytime). Conversely, tbe bedtime group sbowed a sig-nificant inbibition of gastric acidity during tbe nocturnal period compared to tbe morning group (p < 0.01). These results indicate that the relative importance of suppression of gastric acidity on tbe gastric ulcer heal-ing process sbould be evaluated in a clinical trial. 相似文献
998.
999.
Fumi Ohdaira Kazutoshi Nakamura Hideaki Nakayama Makoto Satoh Tetsuro Ohdaira Masami Nakamata Masaki Kohno Akira Iwashima Akira Onda Yoshiaki Kobayashi Katsuya Fujimori Toshio Kiguchi Shuji Izumi Tadaharu Kobayashi Hideo Shinoda Sugata Takahashi Fumitake Gejyo Masaharu Yamamoto 《Sleep & breathing》2007,11(2):93-101
Information on obstructive sleep apnea-hypopnea syndrome (OSAHS) in Japan has been limited. The purposes of this clinical study were to evaluate the demographic characteristics of Japanese OSAHS patients and to assess how demographic factors are associated with OSAHS severity. We analyzed 3,659 OSAHS patients who underwent polysomnographic evaluation between January 2000 and December 2004 at 11 hospitals in Niigata Prefecture, Japan. Data consisted of apnea-hypopnea index (AHI) and demographic characteristics, including sex, age, and body-mass index, for statistical analysis. Levels of obesity were classified according to the WHO criteria. The male-to-female patient ratio for OSAHS was 4.6, and male patients presented more severe OSAHS than female patients. High AHI and a high proportion of moderate to serious OSAHS (AHI > or = 15) were found among the patients in their 30s, as well as female patients in their 70s and male patients in their 80s. The AHI and the proportion of moderate-to-serious OSAHS (AHI > or = 15) were greater in patients classified as underweight than in normal weight patients. In conclusion, there is a higher male predominance in the prevalence of OSAHS, and in both sexes, the results suggest different pathophysiological mechanisms of deteriorating OSAHS between adults under age 55 and adults 55 years or over. In addition, underweight patients exhibit more severe OSAHS than normal weight patients. 相似文献
1000.
Shimaya K Kurihashi A Fuda Y Yajima T Yamami N Shiga T Sakomura Y Matsuda N Ishizuka N Kasanuki H 《International journal of cardiology》2005,98(1):141-145
BACKGROUND: The efficacy of long-term drug therapy for patients with hypertrophic obstructive cardiomyopathy (HOCM) remains unclear. This study was performed to characterize the echocardiographic findings of patients responsive to drug therapy. METHODS: Left ventricular outflow tract (LVOT) gradient and morphologic characteristics of the septum, posterior wall, and mitral valve were measured echocardiographically in 35 Japanese patients. The mean follow-up time was 41+/-22 months. RESULTS: Long-term drug therapy was effective in 14 patients and ineffective in 21 patients. Five of the refractory patients required mitral valve replacement to become free of symptoms. Only 5 of 21 patients whose LVOT gradient was 100 mm Hg were responsive to drug therapy, whereas 9 of 14 patients whose LVOT gradient was <100 mm Hg were responsive to drug therapy. Seven of eight patients with an asymmetric septal hypertrophy (ASH) ratio >==1.3 and LVOT gradient <100 mm Hg were responsive to drug therapy. Only 3 of 16 patients with an ASH ratio <1.3 were responsive to drug therapy. There was no correlation between the efficacy of drug therapy and the morphology of the mitral valve or the width of the LVOT. CONCLUSION: Our results demonstrate that drug therapy effectively reduces the LVOT gradient in patients with asymmetric septal hypertrophy and a less severe LVOT gradient. 相似文献