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91.
Yu Kitaoka Yumiko Takahashi Masanao Machida Kohei Takeda Tohru Takemasa Hideo Hatta 《The journal of physiological sciences : JPS》2014,64(1):59-64
It is now evident that exercise training leads to increases in monocarboxylate transporter (MCT)1 and MCT4, but little is known about the mechanisms of coupling muscle contraction with these changes. The aim of this study was to investigate the effect of 5-aminoimidazole-4-carboxamide-1-beta-d-ribofuranoside (AICAR) induced activation of AMP-activated protein kinase (AMPK) on MCT1, MCT4, and GLUT4 in denervated muscle. Protein levels of MCT4 and GLUT4 after 10 days of denervation were significantly decreased in mice gastrocnemius muscle, while MCT1 protein levels were not altered. AICAR treatment for 10 days significantly increased MCT4, and GLUT4 protein levels in innervated muscle as shown in previous studies. We found that the MCT1 protein level was also increased in AICAR treated innervated muscle. AICAR treatment prevented the decline in MCT4 and GLUT4 protein levels in denervated muscle. Thus, the current study suggests that MCT1 and MCT4 protein expression in muscles, as well as GLUT4, may be regulated by AMPK-mediated signal pathways, and AMPK activation can prevent denervation-induced decline in MCT4 protein. 相似文献
92.
Control of expression of Agrobacterium vir genes by synergistic actions of phenolic signal molecules and monosaccharides 总被引:26,自引:1,他引:26 下载免费PDF全文
Shimoda N Toyoda-Yamamoto A Nagamine J Usami S Katayama M Sakagami Y Machida Y 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(17):6684-6688
Most virulence (vir) genes of Agrobacterium tumefaciens that are required for the formation of crown gall tumors are expressed in response to such plant signal molecules as acetosyringone and lignin precursors. The phenolic signals are transduced through a receptor VirA protein in the inner membrane of the bacterial cell. The expression of these genes triggers the transfer of a specific DNA segment, called transferred DNA (T-DNA), from the Ti plasmid to plant cells, and its integration into their nuclear DNA. We show here that a group of aldoses (L-arabinose, D-xylose, D-lyxose, D-glucose, D-mannose, D-idose, D-galactose, and D-talose) can markedly enhance acetosyringone-dependent expression of vir genes when the concentration of acetosyringone is limited (10 microM) but does not enhance the expression of noninducible genes. Likewise, a 2-deoxy-D-glucose, a nonmetabolized sugar, is also effective. When a deletion was introduced into the virA gene in the region encoding the periplasmic portion of the VirA protein, enhancement by glucose disappeared, but vir expression was induced by acetosyringone in this mutant. These results suggest that these sugars directly enhance a signaling process initiated by phenolic inducers that results in an increase in expression of the vir genes. 相似文献
93.
In this paper, the regioselective reactions of kaolinite and methoxy-modified kaolinite (MeO-Kaol), methanol-expanded kaolinite, with octadecyltrimethylammonium salts are compared. This study mainly concerns the reactions of kaolinite or MeO-Kaol with octadecyltrimethylammonium chloride (C18TAC) in methanol and the subsequent exhaustive washing of the resultant products with ethanol. X-ray diffraction patterns of the products reveal no intercalation of C18TAC between pristine kaolinite layers. Additionally, intercalation and subsequent deintercalation of C18TAC proceed in the product using MeO-Kaol. In the Fourier-transform infrared spectra, the intensities of CH2 stretching bands of the product prepared using MeO-Kaol drastically increase compared to those using kaolinite. In addition, CH2 stretching bands of the product using kaolinite are hardly observed without enlarging the spectrum. The product using MeO-Kaol also displays mass loss in the range of 200–300 °C in the thermogravimetric curve and a nitrogen content with 0.15 mass% estimated using the CHN analysis. These results therefore demonstrate an increase in the available reactive edges in the layered crystal material following an expansion of the stacked layers. 相似文献
94.
Matsuo Koji Mandelbaum Rachel S. Machida Hiroko Yoshihara Kosuke Matsuzaki Shinya Klar Maximilian Muggia Franco M. Roman Lynda D. Wright Jason D. 《Archives of gynecology and obstetrics》2020,301(5):1235-1245
Archives of Gynecology and Obstetrics - To examine trends, characteristics and outcomes of women who develop both ovarian and breast cancers. This is a retrospective study examining the... 相似文献
95.
Comparison of inflammation‐based prognostic scores as predictors of tumor recurrence in patients with hepatocellular carcinoma after curative resection 下载免费PDF全文
96.
Pathogenesis of idiopathic scoliosis. Experimental study in rats. 总被引:19,自引:0,他引:19
STUDY DESIGN: A radiographic examination of pinealectomized rats to observe the development of scoliosis and halt the condition by administration of melatonin. OBJECTIVES: To discover whether pinealectomy has the same effect in mammals as shown in the chicken, and to determine whether the bipedal condition is important for development of scoliosis. SUMMARY OF BACKGROUND DATA: Pinealectomizing chickens shortly after hatching consistently resulted in scoliosis closely resembling human idiopathic scoliosis. It has not been determined whether this phenomenon is restricted solely to chickens, or if this experimental model is applicable to other animals, especially those more closely related to humans. METHODS: A sham operation in five bipedal rats served as the control in this study. Pinealectomy was performed in 10 quadrupedal rats, pinealectomy in 20 bipedal rats, and pinealectomy with implantation of melatonin pellet in 10 bipedal rats. Spinal radiographs were used to measure the degree of scoliosis at 3 months after surgery. RESULTS: Scoliosis developed only in pinealectomized bipedal rats and not in quadrupedal rats. It developed in none of the sham operation group and in only 1 of 10 pinealectomized bipedal rats with melatonin treatment. CONCLUSIONS: Melatonin deficiency secondary to pinealectomy alone does not produce scoliosis if the quadrupedal condition is maintained. The bipedal condition, such as that in chickens or humans, plays an important role in the development of scoliosis. The findings suggest a critical influence of a postural mechanism for the development of scoliosis. 相似文献
97.
Suguru Yamashita Nobutaka Tanaka Michiro Takahashi Motoki Nagai Takatoshi Furuya Yoshio Suzuki Yukihiro Nomura 《World journal of gastrointestinal surgery》2013,5(3):68-72
We present a 70-year-old man who was referred for surgery with uncontrollable hypoglycemia. Ultrasonography and abdominal contrast computed tomography revealed a hypervascular tumor of 1 cm in diameter in the pancreatic tail. With a diagnosis of insulinoma, we performed a distal pancreatectomy. The patient showed a good postoperative course without any complications. The patient’s early morning fasting hypoglycemia disappeared. The respective levels of C-peptide and insulin dropped from 14.9 ng/mL and 4860 μIU/mL preoperatively to 5.3 ng/mL and 553 μIU/mL after surgery. A histopathological examination demonstrated that the tumor was a pancreatic neuroendocrine tumor, grade 1. Immunostaining was negative for insulin and positive for CD56, chromogranin A, synaptophysin and glucagon. These findings suggested that the tumor was clinically an insulinoma but histopathologically a glucagonoma. Among all insulinoma cases reported between 1985 and 2010, only 5 cases were associated with independent glucagonoma. In this report, we characterize and discuss this rare type of insulinoma by describing the case we experienced in detail. 相似文献
98.
Surgical Resection of Hilar Cholangiocarcinoma: Analysis of Survival and Postoperative Complications
Background Surgery is the only potentially curative treatment for hilar bile duct cancer. This study sought to evaluate the efficacy
and feasibility of surgical management of hilar bile duct carcinoma, including radical hepatectomy, at a single institution.
Methods We performed a retrospective review of 49 consecutive patients who underwent surgery at our hospital between 1990 and 2003.
Results Altogether, 44 of 49 patients underwent radical hepatectomy combined with caudate lobectomy and lymphadenectomy. One and four
patients underwent partial hepatectomy or bile duct resection, respectively. No patients underwent preoperative portal vein
embolization. The 5-year survival rate was 39.7%, with a median survival time of 3.75 years. The postoperative morbidity and
mortality rates were 46.8% and 2.0%, respectively. Cox’s proportional hazard model revealed that lymph node status and the
residual tumor factor were independent prognostic factors. Multivariate analysis revealed that preoperative hyperbilirubinemia,
postoperative complications, and extended surgical procedures were independently associated with postoperative hyperbilirubinemia.
After potentially curative resection, 39.4% of patients suffered from disease recurrence. In 60% of the total cases, the sites
of recurrence were distant metastases.
Conclusion Surgery, including radical hepatectomy combined with caudate lobectomy and lymph node dissection, is a feasible, effective
treatment for hilar bile duct cancer. 相似文献
99.
Suguru Ohira M.D. Kiyoshi Doi M.D. Ph.D. Sachiko Maeda M.D. Hitoshi Yaku M.D. Ph.D. 《Echocardiography (Mount Kisco, N.Y.)》2014,31(9):E275-E277
We describe a rare complication after the resection of the left atrial (LA) myxoma. After tumor resection, a large defect of the endocardium was reinforced with an autologous pericardial patch. Transesophageal echocardiography demonstrated a hematoma and pulsatile flow beneath the patch, without patch perforation or detachment. Bleeding increased after closure of the sternum. Intramural hematoma and oozing rupture of the LA were diagnosed. A small intramural vessel of the LA was identified as the main causative site of bleeding. The pericardial patch was repositioned with fibrin glue. Fibrin sheets and glue were applied for reinforcement of the LA from outside. 相似文献
100.