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Moussa Ndong Machiko Kazami Tsukasa Suzuki Mariko Uehara Shin-ichi Katsumata Hirohumi Inoue Ken-Ichi Kobayashi Tadahiro Tadokoro Kazuharu Suzuki Yuji Yamamoto 《Nutrition Research》2009,29(9):640-647
Iron deficiency (ID) is one of the most commonly known forms of nutritional deficiencies. Low body iron is thought to induce neurologic defects but may also play a protective role against cancer development by cell growth arrest. Thus, ID may affect cellular pathways controlling cell growth and proliferation, the mechanism of which is still not fully understood. The serine/threonine protein kinase Akt and its downstream target, the mammalian Target of Rapamycin (mTOR), is known to play a crucial role in the regulation of cell growth and survival. Therefore, we hypothesized that Akt/mTOR pathway could be influenced by ID. Three-week-old male Wistar-strain rats were divided into 3 groups and the 2 groups had free access to a control diet (C group) or an iron-deficient diet (D group). The third group (PF group) were pair-fed the control diet to the mean intake of the D group. After 4 weeks, rats were killed and their brains were sampled. In separate experiments, COS-1 cells were cultured with or without the iron chelator deferoxamine. Western blots of brain samples and COS-1 lysates were used to analyze the expression and phosphorylation state of Akt, TSC2, mTOR, and S6 kinase proteins implicated in the Akt/mTOR pathway. Using 2 different ID models, we show for the first time that iron deficiency depresses Akt activity in rats and in COS-1 cells, leading to a decrease in mTOR activity. 相似文献
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CASE REPORT: A 12-year-old boy who had a history of Kawasaki disease 9 years ago experienced a subarachnoid hemorrhage by ruptured right posterior cerebral artery aneurysm. On day 1 operation, as the aneurysm was very fragile and bled easily, two intraoperative ruptures, including a very premature rupture, were encountered. As a result, a left hemiparesis especially severe in the left hand was caused by the right anterior thalamic infarction due to the occlusion of a thalamo-perforating artery arising near the neck of the aneurysm. DISCUSSION: The histopathological examination of the intraoperative excised aneurysmal dome disclosed the thickening of the endothelial inner due to the endothelial hypertrophy and the invasion of inflammatory cells. This finding of the aneurysm was partially mimicking the finding of the coronary artery of the patients with Kawasaki disease. The combination of cerebral aneurysm and Kawasaki disease has never been reported until now, and the etiology of the aneurysm of this patient is unclear. 相似文献
25.
Studies on isolated smooth muscle cells. IX. Application of papain for isolation of single smooth muscle cells from guinea-pig taenia coli 总被引:1,自引:0,他引:1
M Hasegawa M Kobayashi H Oyamada T Kamishima C Yoshida H Ohata I Maruyama K Momose Y Gomi 《Nippon Heikatsukin Gakkai zasshi》1987,23(1):35-46
To prepare single smooth muscle cells from the taenia coli of guinea pig, the application of papain to the enzymatic solution was examined under two conditions: 1) the isolation in a modified Tyrode solution (containing 0.18 mM Ca2+: 0.18 mM Ca2+-Tyrode solution) and 2) the isolation in a high-K+ Tyrode solution (Na+ was replaced by K+, and Ca2+ was not added: high-K+ Tyrode solution). The presence of papain during collagenase digestion reduced contamination of broken cells and cell debris. In the case of the high-K+ Tyrode solution, papain increased the yield of single cells significantly. The cells were contracted in a dose-dependent manner by Ca2+ in the high-K+ Tyrode solution and by carbachol in 0.18 mM Ca2+-Tyrode solution; furthermore, the contractions were antagonized by verapamil and atropine, respectively. Treatment with papain did not affect cell sensitivity to the stimulants. Therefore, our results suggest that the addition of papain is useful for the isolation of single cells to investigate the physiological and pharmacological characteristics of smooth muscle. 相似文献
26.
Minimum incision endoscopic nephrectomy for giant hydronephrosis 总被引:1,自引:0,他引:1
Fumitaka Koga Kazunori Kihara Hitoshi Masuda Yukio Kageyama Satoru Kawakami Tsuyoshi Kobayashi 《International journal of urology》2007,14(8):774-776
Five consecutive patients with symptomatic giant hydronephrosis underwent minimum incision endoscopic nephrectomy. The originally huge renal specimen was retroperitoneally mobilized using both of endoscopy and direct vision, without the use of trocar ports or gas insufflation, via a single minimum incision that narrowly permitted extraction of the specimen. The specimen was successfully extracted from the incision in all patients. Technically, proper deflation of the hydronephrotic sac facilitates mobilization and enables extraction of the specimen. Median (range) size of incision, operative time, and estimated blood loss were 4 cm (3-5), 205 min (156-222), and 210 mL (110-350), respectively. No patient required blood transfusion or encountered operative complications. Postoperative convalescence was short and uneventful; all patients resumed oral intake and ambulance on the day following surgery, and were physically dischargeable from hospital after 2-3 postoperative days. Thus, this technique is a feasible, minimally invasive and safe procedure for symptomatic giant hydronephrosis. 相似文献
27.
Mizuaki Sakura Satoru Kawakami Hitoshi Masuda Tsuyoshi Kobayashi Yukio Kageyama Kazunori Kihara 《International journal of urology》2007,14(12):1109-1112
Since 1998, we have performed minimum incision endoscopic surgery (MIES) for renal cell carcinoma (RCC). For seven dialysis patients with bilateral RCC, we have performed sequential bilateral MIES radical nephrectomy. It was carried out by retroperitoneal approach through a single minimum incision that narrowly permitted extraction of the specimen using endoscopy and direct stereovision, without trocar ports, without gas insufflation and without the insertion of the hands of operators into the operative field. Although six of the seven patients had multiple complications in addition to chronic renal failure (CRF), bilateral kidneys were successfully removed by sequential MIES radical nephrectomy without major operative complication. Postoperative recovery was prompt with all patients resuming oral feeding and walking by the second postoperative day. Sequential bilateral MIES radical nephrectomy, leaving the peritoneal cavity intact and without imposing circulatory stress caused by gas insufflation, is a feasible treatment for bilateral RCCs in dialysis patients. 相似文献
28.
Katsuyoshi Habiro Hiroaki Shimmura Sakiko Kobayashi Motoko Kotani Yasuo Ishida Kazunari Tanabe Hiroshi Toma Ryo Abe 《American journal of transplantation》2005,5(4):702-711
Previously, we reported that allogeneic skin grafts were rapidly rejected by CD28 and CD40 ligand double deficient mice mediated by CD8+ T cells. These results indicated that some elements in addition to CD28- and CD40-mediated costimulation provide stimulatory signals for the activation of donor-specific CD8+ T cells. In this report, we investigated the role of inflammation associated with transplantation on costimulation-independent priming of CD8+ T cell during graft rejection. B6 RAG1 KO mice were transplanted with BALB/c-skin and adoptively transferred with syngeneic CD8+ T cells the same day or 50 days after transplantation. When blockade of CD28- and CD40-mediated costimulation failed to prevent acute rejection of freshly transplanted skin grafts, it efficiently delayed rejection of well-healed skin grafts. These results showed that factors associated with transplantation have essential roles in inducing costimulation blockade-resistant allograft rejection. Costimulation blockade failed to prevent acute graft-infiltration of NK cells and increasing expression of intragraft IL-12 and IL-15. These factors may trigger the graft-infiltration and priming of CD8+ T cells to induce costimulation blockade-resistant allograft rejection. 相似文献
29.
Self-expandable metallic stent for unresectable malignant strictures in the esophagus and cardia 总被引:2,自引:0,他引:2
Shigeru Lee Harushi Osugi Taigo Tokuhara Masashi Takemura Masahiro Kaneko Yoshinori Tanaka Yushi Fujiwara Satoshi Nishizawa Hiroshi Iwasaki Shigefumi Suehiro 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(9):470-476
Objective Self-expandable metallic stent (EMS) placement has been the first choice for dysphagia because of the certainty over its safety,
low invasiveness, and immediate efficacy. However, there still remain some problems in relation to the EMS placement site
and anticancer therapies before and after EMS placement. Methods: Consecutive 78 patients in whom EMS was placed due to the unresectable malignant stricture in the esophagus or cardia from
July 1995 to August 2003 in our department were studied. Results: Gastroesophageal reflux was found in 5 of 8 patients after placement of conventional EMS for the stricture in the gastroesophageal
junction. Meanwhile, acid and bile reflux into the esophagus were not detected by pH and bilirubin monitoring, respectively,
in 6 patients after placement of the EMS with an anti-reflux mechanism for the stricture in the gastroesophageal junction.
The median survival period of all patients after EMS placement was 123 days. The median survival period of 7 patients with
radiotherapy only after EMS placement was 138 days and that of 17 patients with radiotherapy before EMS placement was 60 days,
which was shorter than that of the former (p<0.05). On the other hand, the median survival period after hospital admission
due to dysphagia of these 7 patients was longer than that of 17 patients with radiotherapy only before EMS placement, although,
the difference was not significant. Conclusion: EMS with an antireflux mechanism is not commercially available in Japan and approval is urgently required. The indication
of radiotherapy associated with EMS placement is to be studied further. 相似文献
30.