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11.
The existence of cytochrome P450 2D isoforms in the brain has been demonstrated, although their physiological functions remain to be elucidated. In this study we demonstrated that recombinant rat cytochrome P450 2D1 and 2D4 and human cytochrome P450 2D6 possess progesterone 6 beta- and 16 alpha- hydroxylation activities; 2 beta- and 21-hydroxylation activities; and 2 beta-, 6 beta-, 16 alpha- and 21-hydroxylation activities, respectively. Cytochrome P450 2D4 had the lowest K(m) value and the highest maximum velocity value toward these activities. Progesterone 2 beta- and 21-hydroxylation activities were also detected in rat brain microsomes, and these activities were completely inhibited by anticytochrome P450 2D antibodies. The presence of endogenous 2 beta- and 21-hydroxyprogesterones in rat brain tissues was also demonstrated. The mRNAs of cytochrome P450 2D4, CYP11A, and 3 beta-hydroxysteroid dehydrogenase were detected in the rat brain, suggesting that progesterone was generated from cholesterol by CYP11A and 3 beta-hydroxysteroid dehydrogenase and then underwent hydroxylation to hydroxyprogesterones by cytochrome P450 2D4 in rat brain. Collectively, our findings support the idea that cytochrome P450 2D may be involved in the regulation (metabolism and/or synthesis) of endogenous neuroactive steroids, such as progesterone and its derivatives, in brain tissues. 相似文献
12.
Expression of p57/Kip2 protein in extrahepatic bile duct carcinoma and intrahepatic cholangiocellular carcinoma 总被引:21,自引:0,他引:21
Ito Y Takeda T Sasaki Y Sakon M Yamada T Ishiguro S Imaoka S Tsujimoto M Monden M Matsuura N 《Liver》2002,22(2):145-149
BACKGROUND: Evaluation of the biological character of carcinomas requires understanding of cell cycle regulators. P57 (Kip2) belongs to the Cip/Kip family and is known to be one of the universal negative regulators of cell cycle. METHODS: In the present study, therefore, we investigated p57 expression in 37 extrahepatic bile duct carcinomas (BDC) and 28 intrahepatic cholangiocellular carcinomas (CCC). RESULTS: The average p57 labeling index (LI) in BDC and CCC were 60.8 +/- 7.9 and 58.6 +/- 18.6, respectively, which were significantly lower (p = 0.0008 and p = 0.0408, respectively) than those in normal duct epithelia (73.1 +/- 7.9, 70.4 +/- 8.2). p57 LI was significantly lower in BDC and CCC cases with biological aggressive phenotypes such as poor differentiation (p = 0.0260 and p = 0.0069), lymph node metastasis (p = 0.0274 and p = 0.0214), high Ki-67 LI (p = 0.0164 and p = 0.0343) and cyclin D1 overexpression (p = 0.0359 and p = 0.0255). CONCLUSION: These findings suggest that decreased p57 expression is related to the increased activity of cell proliferation and also the progression of these carcinomas. 相似文献
13.
Susumu Hijioka Kazuo Hara Nobumasa Mizuno Hiroshi Imaoka Takeshi Ogura Shin Haba Mohamed A. Mekky Vikram Bhatia Waki Hosoda Yasushi Yatabe Yasuhiro Shimizu Yasumasa Niwa Masahiro Tajika Shinya Kondo Tsutomu Tanaka Kiichi Tamada Kenji Yamao 《Journal of hepato-biliary-pancreatic sciences》2012,19(6):650-655
Background
Obtaining histological evidence of gallbladder carcinoma (GBC) is difficult due to its extraductal nature, and pathological confirmation remains challenging. We compared the diagnostic value and safety of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) with endoscopic retrograde cholangiography (ERC) in patients with suspected GBC.Patients
Eighty-three patients with GBC were evaluated. Prior to definitive management, pathological evidence of GBC was obtained through either ERC cytopathologic sampling (n?=?33), EUS-FNA (n?=?24) or both (n?=?26).Results
Among the 83 patients, 59 (71.0%) with biliary obstruction were sampled using ERC with 47.4% (28/59) sensitivity. In 19 of the remaining 31 cases, EUS-FNA sampling had 100% diagnostic sensitivity. Likewise, 50 (60.2%) of the 83 patients with suspected GBC underwent EUS-FNA of regional lymph nodes or the gallbladder (GB) mass itself with 94.8% sensitivity. The overall diagnostic sensitivity rates of ERC and EUS-FNA were 47.4 and 96%, respectively (P?<?0.001). Post-procedural complications were seen in 6.7% of the ERC group (4/59, all were mild pancreatitis), and in none of the EUS-FNA group (P?=?0.10).Conclusions
Gallbladder carcinoma sampling using ERC and EUS-FNA should be incorporated into the diagnostic workup of GB lesions as complementary tools, and EUS-FNA should be applied in the setting of failed or not indicated ERC. 相似文献14.
Cytokeratin deposits in lymph nodes show distinct clinical significance from lymph node micrometastasis in human esophageal cancers 总被引:6,自引:0,他引:6
Doki Y Ishikawa O Mano M Hiratsuka M Sasaki Y Kameyama M Ohigashi H Murata K Yamada T Miyashiro I Yokoyama S Ishiguro S Imaoka S 《The Journal of surgical research》2002,107(1):75-81
BACKGROUND: Cytokeratin immunostaining is the most common method used to identify micrometastatic cancer cells from the lymph nodes. However, contamination with hyalinized cytokeratin particles, frequently observed in the lymph nodes of esophageal cancer patients, can lead to misinterpretation of cytokeratin immunostaining. MATERIALS AND METHODS: Cytokeratin immunostaining (AE1/AE3) of surgically removed lymph nodes was performed for 41 cases of node-negative, but locally advanced (T3, T4), esophageal cancer patients. Cytokeratin immunoreactivity (CK) was classified as micrometastasis (MM) or cytokeratin deposit (CD) by the presence or absence of tumor nuclei in serial sections given hematoxylin-eosin staining. RESULTS: CK (+) was observed in 18 patients (44%), including 11 with MM (+) (27%) and 10 with CD (+) (24%). There was no correlation between MM and CD, and neither was associated with clinicopathological factors, except for a high incidence of preoperative chemotherapy in CD (+) patients. The presence of CK did not affect postoperative survival of esophageal cancer patients at this limited stage, showing a 5-year survival rate of 57% for CK (+) and 64% for CK (-) (P = 0.6064). Interestingly, patients with MM (+) showed poorer prognosis than MM (-) (5-year survival: 28% vs 79%, P = 0.0188), while CD (+) patients tended to display better prognosis than CD (-) ones (5-year survival: 78% vs 56%, P = 0.1860). CONCLUSIONS: Evaluation by cytokeratin immunostaining of lymph nodes requires careful discrimination of CD from MM, in order to allow MM to be used as a prognostic factor for esophageal cancer patients. 相似文献
15.
Radical resection for pancreatic cancer 总被引:10,自引:0,他引:10
Ishikawa O Ohigashi H Yamada T Sasaki Y Imaoka S Nakaizumi A Uehara H Tanaka S Takenaka A 《Acta gastro-enterologica Belgica》2002,65(3):166-170
Ductal adenocarcinoma of the pancreas is still characterized by (1) poor prognosis after surgery and (2) extreme difficulty in early diagnosis, and we need a breakthrough. For the first problem, we have performed a wide range of lymphatic and connective tissue clearance (extended pancreatectomy) which has succeeded in improving the 5-year survival rate from 8% to 24% via decreasing the incidence of locoregional recurrence. When liver perfusion chemotherapy via the hepatic artery and the portal vein was added to the patients who had received extended pancreatectomy, the 5-year survival rate was further elevated to 40% via decreasing the incidence of hepatic metastasis. We conclude that pancreatic cancer should be treated by the better-balanced treatments between locoregional control and prevention of hepatic metastasis. For the second problem, we have more actively collected pancreatic juice to perform cytodiagnosis even though no obvious tumor was delineated by the conventional imaging diagnoses. When cancer cells were detected in the pancreatic juice, our method of intraoperative cytology was very useful in precisely locating the occult lesion indicating an appropriate range of pancreatectomy. The resected pancreas was proven to have included borderline malignancy and in situ or minimally-invasive carcinoma by the postoperative histology, and disease-free 5-year survival rate was 100%. In the future, we need to detect patients with a high risk of pancreatic cancer and develop a less-painful method to collect the pancreatic juice. 相似文献
16.
Carlo La Vecchia Eva Negri Silvia Franceschi Barbara D’Avanzo Peter Boyle J. Larsson J. Permert G. Del Favero D. Basso P. Fogar M. P. Panozzo T. Meggiato C Ferrara F. D’Angeli L. Brigato M. Plebani Osamu Ishikawa Shoji Nakamori Hiroaki Ohigashi Singi Imaoka Åke AndrénSandberg Joe Ariyama Johan Permert Jörgen Larsson Parviz M. Pour Johan Permert Masashito Mogaki Katherine Kazakoff Lucio Gullo Raffaele Pezzilli Thomas E. Adrian Johan Permert Jörgen Larsson Gunilla T. Westermark 《Journal of gastrointestinal cancer》1994,16(1):81-98
17.
Christian Wittekmd Paul Hermanek Yoshifumi Kawarada Kentaro Yamagiwa Shuji Isaji Ryuji Mizumoto Di Carlo Valerio Zerbi Alessandro Balzano Gianpaolo Tsunoda Tsukasa Eto Toshifumi Tsuchiya Ryoichi Ishikawa Osamu Ohigashi Hiroaki Nakamori Shoji Imaoka Shingi H. G. Beger M. H. Schoenberg D. Birk Eugene P. DiMagno Tomioka Tsutomu Kanematsu Takashi Ariyama Joe Yamamoto Masahiro Ohashi Osamu Hidehumi Ishida Takashi Kamigaki Hirohiko Onoyama Yoichi Saitoh 《Journal of gastrointestinal cancer》1994,16(1):99-120
18.
Detection of Gastric Cancer Micrometastases in Lymph Nodes by Amplification of Keratin 19 mRNA with Reverse Transcriptase-Polymerase Chain Reaction 总被引:10,自引:0,他引:10
19.
A. Hagiwara T. Matsuda S. Tamano M. Kitano S. Imaoka Y. Funae Y. Takesada T. Shirai S. Fukushima 《Cancer letters》1996,110(1-2):155-162
The dose-response relationship between liver tumor promoting activity and cytochrome P-450 (CYP) induction by phenobarbital sodium (PB) was investigated using the liver medium-term bioassay system of Ito. Two weeks after a single dose of N-nitrosodiethylamine (DEN) (200 mg/kg body weight, i.p.), rats were given PB at dietary levels of 500, 250, 125, 60, 30, 15 and 8_parts per million (ppm) for 6 weeks. All rats were subjected to partial hepatectomy at week 3, and were killed at week 8. Quantitative values for glutathione S-transferase placental form positive hepatocytic (GST-P+) foci were increased in the high dose groups dose-dependently. In contrast, the values in the low dose groups were rather lower than that of the control. CYP2B1, 2C6 and 3A2 were predominantly immunostainable in hepatocytes around the central vein. While Western blotting revealed CYP2B1 and 2C6 proteins to be increased with strict dose-dependence, CYP3A2 was only elevated at high doses. Thus, a good correlation between increase of GST-P+ foci and CYP3A2 induction was observed, as well as with CYP2B1 and 2C6 in high dose groups. 相似文献
20.
Laparoscopic management of common bile duct stones: transcystic approach and choledochotomy 总被引:25,自引:0,他引:25
Tokumura H Umezawa A Cao H Sakamoto N Imaoka Y Ouchi A Yamamoto K 《Journal of Hepato-Biliary-Pancreatic Surgery》2002,9(2):206-212
The purpose of this study was to review our experience with laparoscopic common bile duct (CBD) exploration by the transcystic
approach and choledochotomy. We selected the transcystic approach for patients whose CBD stones were less than five in number
and smaller than 9 mm in diameter, and whose CBD was less than 15 mm in diameter on cholangiograms. Among 217 patients with
CBD stones treated laparoscopically, the transcystic approach was performed successfully in 91 of 104 patients in whom it
was attempted (87.5%). The other 126 patients underwent laparoscopic choledochotomy, followed by ductal closure with transcystic
drainage in 59, T-tube drainage in 46, primary ductal closure in 19, and choledochoduodenostomy in 1. Choledochotomy was converted
to open surgery in only 1 patient. The transcystic approach was associated with shorter hospital stay and less morbidity than
choledochotomy. However, choledochotomy also had an acceptably low rate of complications. Bile leaks occurred more frequently
in those with primary ductal closure than in those with transcystic drainage or T-tube drainage. Residual stones were found
in 2 patients with the transcystic approach and in 10 with choledochotomy. The residual stones were removed through the T-tube
tract by choledochoscopy in 7 of these 10 patients. From these results we conclude that laparoscopic management of CBD stones
is feasible for almost all patients with CBD stones. It is considered to be safe and effective and has the advantage of being
a single-stage procedure.
Received: July 7, 2000 / Accepted: October 26, 2000 相似文献