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61.
Shibuya R Suzuki T Miki Y Yoshida K Moriya T Ono K Akahira J Ishida T Hirakawa H Evans DB Sasano H 《Endocrine-related cancer》2008,15(1):113-124
It is well known that sex steroids play important roles in the development of invasive ductal carcinoma (IDC) of the human breast. However, biological significance of sex steroids remains largely unclear in ductal carcinoma in situ (DCIS), regarded as a precursor lesion of IDC, which is partly due to the fact that the intratumoral concentration of sex steroids has not been examined in DCIS. Therefore, in this study, we first examined the intratumoral concentrations of estradiol and 5alpha-dihydrotestosterone (DHT) using liquid chromatography/electrospray tandem mass spectrometry in DCIS. Intratumoral concentrations of both estradiol and DHT were threefold higher in DCIS than non-neoplastic breast tissues and estrogen-producing enzymes (aromatase, steroid sulfatase, and 17beta-hydroxysteroid dehydrogenase type 1 (17betaHSD1)), and androgen-producing enzymes (17betaHSD5 and 5alpha-reductase type 1 (5alphaRed1)) were abundantly expressed in DCIS by real-time PCR and immunohistochemical analyses. The intratumoral concentration of DHT was significantly lower in IDC than DCIS, while the expression of aromatase mRNA in carcinoma cells and intratumoral stromal cells was significantly higher in IDC than those in DCIS. Immunohistochemistry for sex steroid-producing enzymes in DCIS demonstrated that 5alphaRed1 immunoreactivity was positively correlated with Ki-67 labeling index and histological grade and was also associated with an increased risk of recurrence in patients with DCIS examined. Results of our study suggest that intratumoral concentrations of estradiol and DHT are increased in DCIS, which is possibly due to intratumoral production of these steroids. Therefore, estradiol and DHT may play important roles in the development of DCIS of the human breast. 相似文献
62.
Katsuhiko Hatake Ichiro Wakabayashi Eizo Kakishita Tadaaki Taniguchi Harumi Ouchi Shigeru Hishida 《Alcoholism, clinical and experimental research》1991,15(1):112-115
Rats were maintained on liquid diets containing ethanol (35% of total calories) or an equicaloric volume of sucrose instead of ethanol for 10 wk. Vascular strips of isolated rat aortas were mounted in organ chambers to record isometric tension. Ethanol in vitro inhibited the endothelium-dependent relaxation responses to acetylcholine and ATP in both pair-fed control and ethanol-fed rats. The inhibitory effect of ethanol was greater in the pair-fed rats. In addition, the magnitudes of these relaxation responses in the absence of ethanol in vitro in pair-fed rats were similar to those in the presence of ethanol in ethanol-fed rats. In the absence of ethanol in vitro, the relaxations in response to acetylcholine and ATP in the ethanol-fed rats were greater than in the pair-fed rats. These results suggest that chronic ethanol consumption can induce tolerance to ethanol-induced inhibition of endothelium-dependent relaxation responses to acetylcholine and ATP, and that the relaxations can become adapted to the presence of plasma levels of ethanol, which may inhibit the relaxation in vivo. The augmented relaxation in the ethanol-fed rats may result from the mechanism causing tolerance to the inhibitory effect of ethanol. 相似文献
63.
64.
Angiotensin-(1-7). A member of circulating angiotensin peptides. 总被引:3,自引:0,他引:3
We measured the concentrations of three principal products of the renin-angiotensin system and seven of their metabolites in the plasma of anesthetized normal dogs and in dogs 24 hours after bilateral nephrectomy. The levels of the angiotensin peptides were measured by high-performance liquid chromatography combined with radioimmunoassay using three specific antibodies that recognized different epitotes in the sequences of angiotensin I, angiotensin II, and angiotensin-(1-7). The analysis revealed that angiotensin-(1-7) is present in the plasma of intact (4.9 +/- 2.2 fmol/ml) and nephrectomized (0.5 +/- 0.5 fmol/ml) dogs. An intravenous injection of purified hog renin (0.01 Goldblatt unit/kg) increased plasma levels of angiotensin I, angiotensin II, and angiotensin-(1-7) both before and after nephrectomy. These changes were associated with parallel increases in the concentrations of fragments of the three parent peptides. Administration of MK-422 led to the disappearance of circulating angiotensin II and its fragments both before and after a second injection of the same dose of renin. In contrast, MK-422 augmented the plasma levels of both angiotensin I and angiotensin-(1-7). The concentrations of these two peptides, but not the blood pressure, were again augmented by a second injection of renin given after blockade of converting enzyme. These effects were observed both before and after bilateral nephrectomy. These findings show that angiotensin-(1-7) circulates in the blood of normal and nephrectomized dogs. In addition, we found that angiotensin-(1-7) is generated in the blood from the cleavage of angiotensin I through a pathway independent of converting enzyme (EC 3.4.15.1). 相似文献
65.
66.
Impact of reflux esophagitis on the esophageal function before and after laparoscopic fundoplication
Masato Hoshino Nobuo Omura Fumiaki Yano Kazuto Tsuboi Se Ryung Yamamoto Shunsuke Akimoto Takahiro Masuda Hideyuki Kashiwagi Katsuhiko Yanaga 《Esophagus》2018,15(4):224-230
Background
High-resolution manometry (HRM), which is breakthrough testing equipment to evaluate esophageal motor function, was developed in Europe and United State and has garnered attention. Moreover, multichannel intraluminal impedance pH (MII-pH) testing has allowed us to grasp all liquid/gas reflux including not only acid but also non-acid reflux. We examined the impact of the presence of reflux esophagitis (RE) on esophageal motor function before and after laparoscopic fundoplication.Materials and methods
The subjects included 100 patients (male: 63 patients, mean age: 54.1?±?15.8) among 145 patients who underwent laparoscopic fundoplication for GERD associated diseases during a 4-year period from October 2012 to September 2016, excluding 6 patients who underwent further surgery, 32 patients on whom HRM was not performed, 3 patients who had technical errors during testing, and 4 patients for whom the status of RE was unknown. Regarding HRM, Mano Scan from Given Imaging Ltd. was used, and for the analysis, Mano View version 3.0 from the same company was used, after which data was calculated based on the Chicago Classification advocated by Pandolfino et al. Moreover, for the MII-pH testing, Sleuth manufactured by Sandhill Scientific. Inc. was used and automatic analysis was conducted by a computer. Postoperative assessments were conducted 3 months following surgery for all. Data was described in the median value and inter-quartile range, with a statistically significant difference defined as p?<?0.05 by Chi square, Mann–Whitney, and Wilcoxon tests.Results
RE+?group (Los Angeles classification A:B:C:D?=?7:9:16:12 patients) included 44 patients (44%), of older age compared to the RE? group (62 vs. 50 years, p?=?0.012) and a higher Body Mass Index value (24.0 vs. 22.5, p?=?0.045); however, no differences were observed in terms of gender and duration of symptoms. In the preoperative findings on MII-pH, the RE+?group demonstrated significantly longer acid reflux time (4.7 vs. 1.3%, p?=?0.005), while in the HRM findings, the RE? group demonstrated a significantly longer abdominal esophagus (0 vs. 0.4 cm, p?=?0.049) and maintained esophageal body motor function (DCI: 1054 vs. 1407 mmHg s cm, p?=?0.021, Intact peristalsis ratio: 90 vs. 100%, p?=?0.037). As to the comparison of the treatment effect before and after laparoscopic fundoplication (Toupet fundoplication for all), significant improvements were observed in both groups in various parameters regarding reflux including acid reflux time, total number of liquid reflux episodes and total number of reflux episodes. Moreover, for both groups, the total length of the lower esophageal sphincter (LES) (RE+?group: 2.7 vs. 3.2 cm, p?=?0.001, RE? group: 3.0 vs. 3.4 cm, p?=?0.003) and the total length of the abdominal esophagus (RE+?group: 0 vs. 1.6 cm, p?<?0.001, RE? group: 0 vs. 1.8 cm, p?=?0.001) were significantly extended following surgery; however, no change was observed in DCI before and after surgery.Conclusions
Regardless of the presence of RE, cardiac function and LES function were improved following laparoscopic Toupet fundoplication, but no changes were observed in esophageal body motor function.67.
Kazutoshi Higuchi Seiji Futagami Hiroshi Yamawaki Makoto Murakami Kumiko Kirita Shuhei Agawa Go Ikeda Hiroto Noda Yasuhiro Kodaka Nobue Ueki Keiko Kaneko Katya Gudis Ryuji Ohashi Katsuhiko Iwakiri 《Journal of Clinical Biochemistry and Nutrition》2021,68(1):86
Since the prevention of early chronic pancreatitis (ECP) into chronic pancreatitis might be critical for the reduction of pancreatic cancer, we tried to clarify the pathophysiology of ECP patients, focusing on ECP patients without alcoholic chronic pancreatitis. 27 ECP patients without alcoholic chronic pancreatitis and 33 patients with functional dyspepsia with pancreatic enzyme abnormalities (FD-P) were enrolled in this study. Diagnosis of ECP was made when imaging findings showed the presence of more than 2 out of 7 endoscopic ultrasound features. Duodenal degranulated eosinophils and glucagon-like peptide 1 producing cells were estimated by immunostaining. There were no significant differences in characteristics and psychogenic factors between ECP and FD-P patients. Interestingly, endoscopic ultrasound score in ECP patients significantly improved, albeit clinical symptoms in ECP patients showed no improvement at one year follow up. The extent of migration of duodenal degranulated eosinophils in FD-P patients was significantly higher compared to that in ECP patients. The levels of elastase-1 and trypsin in ECP patients with improved endoscopic ultrasound features were significantly reduced by the treatment. Further studies will be needed to clarify whether clinical symptoms and endoscopic ultrasound features in ECP patients without alcoholic chronic pancreatitis were improved in longer follow up study. 相似文献
68.
Fumihiko Yasui Masayuki Sudoh Masaaki Arai Michinori Kohara 《Journal of medical virology》2013,85(2):241-249
The influence of the intracellular redox state on the hepatitis C virus (HCV) life cycle is poorly understood. This study demonstrated the anti‐HCV activity of 2,3‐dihydro‐5‐hydroxy‐2,2‐dipentyl‐4,6‐di‐tert‐butylbenzofuran (BO‐653), a synthetic lipophilic antioxidant, and examined whether BO‐653's antioxidant activity is integral to its anti‐HCV activity. The anti‐HCV activity of BO‐653 was investigated in HuH‐7 cells bearing an HCV subgenomic replicon (FLR3‐1 cells) and in HuH‐7 cells infected persistently with HCV (RMT‐tri cells). BO‐653 inhibition of HCV replication was also compared with that of several hydrophilic and lipophilic antioxidants. BO‐653 suppressed HCV replication in FLR3‐1 and RMT‐tri cells in a concentration‐dependent manner. The lipophilic antioxidants had stronger anti‐HCV activities than the hydrophilic antioxidants, and BO‐653 displayed the strongest anti‐HCV activity of all the antioxidants examined. Therefore, the anti‐HCV activity of BO‐653 was examined in chimeric mice harboring human hepatocytes infected with HCV. The combination treatment of BO‐653 and polyethylene glycol‐conjugated interferon‐α (PEG‐IFN) decreased serum HCV RNA titer more than that seen with PEG‐IFN alone. These findings suggest that both the lipophilic property and the antioxidant activity of BO‐653 play an important role in the inhibition of HCV replication. J. Med. Virol. 85:241–249, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
69.
Fumitoshi Sakazaki Hitoshi Ueno Katsuhiko Nakamuro 《Immunopharmacology and immunotoxicology》2013,35(3-4):597-609
The effect of 17β-estradiol (E2) on murine contact hypersensitivity (CHS), thymic atrophy, and hair-cycle change related to growth was investigated. Female mice were ovariectomized. E2 (3.2 μg) was injected subcutaneously along with the sensitizer 4‐ethoxymethylene-2-phenyl-2-oxazolin-5-one (OXA), and a hypersensitive reaction was elicited with OXA on the ear in mice of various ages. E2 enhanced allergy only in 3- and 7-week-old mice, just prior to hair regrowth. Age-related thymus atrophy was repressed in the E2-treated mice compared with the control mice. E2 alone did not cause thymus involution, but it did inhibit thymus involution and regeneration after CHS. 相似文献
70.
Masako Ueyama Kazue Mizuno Dai Hirose Katsuhiko Kamei Ken Ohta 《Journal of infection and chemotherapy》2021,27(5):759-765
This is a case report of allergic fungal rhinosinusitis caused by Schizophyllum commune (S. commune) identified in a patient's nasal mucus and environmental soil sample using (r)DNA sequencing. Although filamentous basidiomycetes, including S. commune, are known as environmental pathogens causing allergic respiratory diseases worldwide, many patients with infections caused by S. commune have not been correctly diagnosed. Repeated exposures to environmental floating fungi supposedly make an easy sensitization and colonization of fungi in the nasal passages, resulting in the onset of allergic fungal rhinosinusitis due to S. commune in our living environments. This report indicates the importance of reconsidering allergic respiratory diseases associated with our living environments. 相似文献