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51.
Yang Liu Yoshifumi Baba Takatsugu Ishimoto Hiroyasu Tsutsuki Tianli Zhang Daichi Nomoto Kazuo Okadome Kensuke Yamamura Kazuto Harada Kojiro Eto Yukiharu Hiyoshi Masaaki Iwatsuki Yohei Nagai Shiro Iwagami Yuji Miyamoto Naoya Yoshida Yoshihiro Komohara Masaki Ohmuraya Xiaoming Wang Jaffer A. Ajani Tomohiro Sawa Hideo Baba 《British journal of cancer》2021,124(5):963
Background Fusobacterium nucleatum (F. nucleatum) is a gut microbe implicated in gastrointestinal tumorigenesis. Predicting the chemotherapeutic response is critical to developing personalised therapeutic strategies for oesophageal cancer patients. The present study investigated the relationship between F. nucleatum and chemotherapeutic resistance in oesophageal squamous cell carcinoma (ESCC).Methods We examined the relationship between F. nucleatum and chemotherapy response in 120 ESCC resected specimens and 30 pre-treatment biopsy specimens. In vitro studies using ESCC cell lines and co-culture assays further uncovered the mechanism underlying chemotherapeutic resistance.Results ESCC patients with F. nucleatum infection displayed lesser chemotherapeutic response. The infiltration and subsistence of F. nucleatum in the ESCC cells were observed by transmission electron microscopy and laser scanning confocal microscopy. We also observed that F. nucleatum modulates the endogenous LC3 and ATG7 expression, as well as autophagosome formation to induce chemoresistance against 5-FU, CDDP, and Docetaxel. ATG7 knockdown resulted in reversal of F. nucleatum-induced chemoresistance. In addition, immunohistochemical studies confirmed the correlation between F. nucleatum infection and ATG7 expression in 284 ESCC specimens.Conclusions F. nucleatum confers chemoresistance to ESCC cells by modulating autophagy. These findings suggest that targeting F. nucleatum, during chemotherapy, could result in variable therapeutic outcomes for ESCC patients.Subject terms: Tumour biomarkers, Oesophageal cancer 相似文献
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N Emoto T Tsushima K Shizume T Tanaka M Saji Y Ohba K Wakai M Arai E Ohmura 《Acta endocrinologica》1987,114(2):283-291
Nb2 cell is a rat lymphoma cell line that responds to lactogens such as prolactin and human growth hormone (hGH) with an increased rate of proliferation. We explored the relationship between the biochemical events induced by hGH and its derivatives and their receptor binding activities. hGH stimulated RNA, DNA and protein synthesis of Nb2 cells as a function of time. Stimulation of RNA and protein was maximal at 2-3 h and 12 h, respectively, after the addition of hGH. DNA synthesis, measured by the rate of [3H]thymidine incorporation, reached a maximum after 18-h incubation with hGH. Stimulation of DNA synthesis was elicited by hGH in a dose-dependent manner between 0.45 and 45 pmol/l. The activity of the 20 K hGH variant in stimulating DNA synthesis was approx 30% of that of hGH. In contrast, S1-hGH, which lacks a sequence of ten amino acids (140-149) of hGH, showed a 3.2-fold greater activity than hGH. F1 (amino-terminal sequence 1-134 of hGH) was only 0.06% as active as hGH, and the activity of F2 (C-terminal 42 amino acid residue of hGH) was less than 0.01%. Both fragment 1-15 and 32-46 were without effect. The relative potencies of these hGH derivatives in stimulating DNA synthesis were similar to their relative abilities to inhibit [125I]hGH binding to lactogenic receptors on Nb2 cell. Nb2 cells provide a suitable model to study the relationship between receptor binding and the biochemical events induced by lactogens. 相似文献
55.
Microvascular resistance in response to iodinated contrast media in normal and functionally impaired kidneys
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Osamu Kurihara Masamichi Takano Saori Uchiyama Isamu Fukuizumi Tetsuro Shimura Masato Matsushita Hidenori Komiyama Toru Inami Daisuke Murakami Ryo Munakata Takayoshi Ohba Noritake Hata Yoshihiko Seino Wataru Shimizu 《Clinical and experimental pharmacology & physiology》2015,42(12):1245-1250
Contrast‐induced nephropathy (CIN) is considered to result from intrarenal vasoconstriction, and occurs more frequently in impaired than in normal kidneys. It was hypothesized that iodinated contrast media would markedly change renal blood flow and vascular resistance in functionally impaired kidneys. Thirty‐six patients were enrolled (32 men; mean age, 75.3 ± 7.6 years) undergoing diagnostic coronary angiography and were divided into two groups based on the presence of chronic kidney disease (CKD), defined as an estimated glomerular filtration rate (eGFR) of < 60 mL/min per 1.73 m2 (CKD and non‐CKD groups, n = 18 in both). Average peak velocity (APV) and renal artery resistance index (RI) were measured by Doppler flow wire before and after administration of the iodinated contrast media. The APV and the RI were positively and inversely correlated with the eGFR at baseline, respectively (APV, R = 0.545, P = 0.001; RI, R = ?0.627, P < 0.001). Mean RI was significantly higher (P = 0.015) and APV was significantly lower (P = 0.026) in the CKD than in the non‐CKD group. Both APV (P < 0.001) and RI (P = 0.002) were significantly changed following contrast media administration in the non‐CKD group, but not in the CKD group (APV, P = 0.258; RI, P = 0.707). Although renal arterial resistance was higher in patients with CKD, it was not affected by contrast media administration, suggesting that patients with CKD could have an attenuated response to contrast media. 相似文献
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Sakamoto Kazumasa Ito Kiyoaki Yotsuyanagi Hiroshi Yatsuhashi Hiroshi Tanaka Yasuhito Hige Shuhei Takikawa Yasuhiro Ueno Yoshiyuki Yamamoto Kazuhide Imazeki Fumio Inoue Jun Kurosaki Masayuki Umemura Takeji Toyoda Hidenori Mita Eiji Michitaka Kojiro Maeshiro Tatsuji Yamada Norie Suetsugu Atsushi Kawanaka Miwa Seko Yuya Matsuura Kentaro Okumura Akinori Fukuzawa Yoshitaka Sugiyama Masaya Mizokami Masashi Yoneda Masashi 《Journal of gastroenterology》2022,57(12):971-980
Journal of Gastroenterology - Hepatitis B virus (HBV) is one of the most prevalent chronic viral infections that causes chronic hepatitis B (CHB). In Japan, genotypes B and C account for most of... 相似文献
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Sixty-eight cases of single hepatocellular carcinoma (HCC) with less than 3 cm of diameter were immunohistochemically examined for the expressions of alpha-fetoprotein (AFP) and protein induced by vitamin K absence or antagonist II (PIVKA-II). In cancerous tissues, the expression rate was significantly higher for PIVKA-II (34 cases [50%]) than AFP (21 cases [31%]) (P <.05), suggesting a higher specificity of PIVKA-II to small HCC. Sixteen of the 68 cases (24%) were positive to both AFP and PIVKA-II, and in 8 of the 16 cases, AFP and PIVKA-II expressing areas within a nodule were clearly divided by a fibrous septum. According to histologic grades, PIVKA-II expression was confirmed in 2 of the 15 well-differentiated HCCs, and in the well-differentiated component of 6 of the 12 "nodule-in-nodule"-type well-differentiated HCCs. AFP expression was not found in well-differentiated HCCs, but found in 16 of the 40 moderately differentiated HCCs (40%) and in the moderately differentiated component of 3 of the 12 "nodule-in-nodule"-type well-differentiated HCCs. The positive rate in the tissues was correlated to the serum levels for both AFP and PIVKA-II. In addition, frequency of tissue-PIVKA-II expression was higher than tissue-AFP expression in the cases whose serum protein level was within the normal range. This indicates that AFP and PIVKA-II have different patterns of tissue expression and of secretion to the blood. In comparison with tissue-AFP-negative cases, tissue-AFP-positive HCCs had a larger tumor size, higher frequencies of portal vein invasion and intrahepatic metastasis, a high Ki-67 labeling index, and a lower rate of recurrence-free survival. Thus, tissue-AFP-positive HCCs are suggested to be biologically more malignant than those HCCs that are AFP-negative and PIVKA-II-positive. 相似文献
59.
Masashi Mizokami Etsuro Orito Yukio Gibo Kaoru Suzuki Ken-ichi Ohba Tomoyoshi Ohno Johnson Y. N. Lau 《Liver international》1996,16(1):23-27
Abstract: To determine whether pretreatment HCV-RNA level, hepatitis C virus genotypes, alanine aminotransferase and histology correlate with subsequent response to interferon-α therapy or not, serum HCV-RNA levels and genotype were determined by branched DNA signal amplification assay and genotype-specific polymerase chain reaction in 43 patients with chronic active hepatitis C. Response to recombinant interferon-α 2α (504 million units in total) was defined as complete and sustained CR→SR, n=12), complete response followed by relapse (CR→Rel, n=17), and no response (NR, n=10), excluding dropouts (n=4). Patients who showed CR→SR had a lower HCV-RNA level (0.438 × 106 eq/ml) compared to CR→Rel (2.452 × 106 eq/ml, p=0.008) and NR (4.882 × 106 eq/ml, p=0.009). A higher proportion of patients with CR→SR had type 2a HCV (67%) compared to the CR→Rel (28%) and the NR (0%). There was a trend for type 1b hepatitis C virus infection to have higher serum HCV-RNA levels. There was no correlation between pretreatment HCV-RNA level and alanine aminotransferase. However, no relation between pretreatment HCV-RNA level and liver histology was observed; a high proportion of patients with CAH2a showed CR→SR, compared to those with CAH2b (p=0.001). Moreover, the patients with CAH2b who had low level hepatitis C virus viremia did not show CR→SR. These data indicate that pre-treatment serum HCV-RNA levels, genotype and liver histology are good predictors of subsequent response to interferon-α therapy in Japanese patients with chronic hepatitis C virus infection. 相似文献
60.
Ayabe M Brubaker PH Dobrosielski D Miller HS Ishi K Yahiro T Kiyonaga A Shindo M Tanaka H 《Journal of cardiopulmonary rehabilitation》2004,24(2):80-86
PURPOSE: This investigation aimed to examine the physical activity patterns of cardiac rehabilitation program (CRP) participants. METHODS: The investigation enrolled 53 male and 24 female CRP participants between 46 and 88 years of age. By means of a uniaxial accelerometer (Life-Corder), the amount of physical activity (in kilocalories) and the time spent in physical activity at light (<3 metabolic equivalents [METs]), moderate (3 to 6 METs), and vigorous (>6 METs) intensity were evaluated. In addition to these variables, the MET levels for the CRP and non-CRP periods were calculated. RESULTS: The weekly amount of physical activity energy expenditure averaged 1597 +/- 846 kcal/week, and the time spent in light, moderate, and vigorous physical activity averaged, respectively, 375.5 +/- 124.5 minutes, 125.2 +/- 109.4 minutes, and 5.7 +/- 12.8 minutes per week. These levels were significantly lower on non-CRP days than on CRP days: 177 +/- 113 versus 299 +/- 161 kcal/day and, respectively, 49.3 +/- 19.3 versus 59.7 +/- 19.8 minutes, 10.5 +/- 14.6 versus 26.4 +/- 20.4 minutes, and 0.4 +/- 1.7 versus 1.4 +/- 3.0 minutes per day. CONCLUSIONS: These results indicate that the amount of physical activity was generally adequate on CRP days, but failed to reach target levels on non-CRP days. Thus CRP participants, when it is medically appropriate, should be encouraged to incorporate lifestyle physical activity, additional exercise, or both on non-CRP days to supplement their caloric expenditure from CRP exercise sessions. 相似文献