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51.
Takashi Akasaki Yusuke Ohya Junya Kuroda Kimika Eto Isao Abe Hideki Sumimoto Mitsuo Iida 《Hypertension research》2006,29(10):813-820
Although vascular cells express multiple members of the Nox family of nicotinamide adenine dinucleotide phosphate (NAD(P)H) oxidase, including gp91phox, Nox1, and Nox4, the reasons for the different expressions and specific roles of these members in vascular injury in chronic hypertension have remained unclear. Thus, we quantified the mRNA expressions of these NAD(P)H oxidase components by real-time polymerase chain reaction and evaluated superoxide production and morphological changes in the aortas of 32-week-old stroke-prone spontaneously hypertensive rats (SHRSP) and age-matched Wistar Kyoto rats (WKY). The aortic media of SHRSP had an approximately 2.5-fold greater level of Nox4 mRNA and an approximately 10-fold greater level of Nox1 mRNA than WKY. The mRNA expressions of gp91phox and p22phox in SHRSP and WKY were comparable. SHRSP were treated from 24 weeks of age for 8 weeks with either high or low doses of candesartan (4 mg/kg/day or 0.2 mg/kg/day), or a combination of hydralazine (30 mg/kg/day) and hydrochlorothiazide (4.5 mg/kg/day). The high-dose candesartan or the hydralazine plus hydrochlorothiazide decreased the blood pressure of SHRSP to that of WKY, whereas the low-dose candesartan exerted no significant antihypertensive action. Media thickening and fibrosis, as well as the increased production of superoxide in SHRSP, were nearly normalized with high-dose candesartan and partially corrected with low-dose candesartan or hydralazine plus hydrochlorothiazide. These changes by antihypertensive treatment paralleled the decrease in mRNA expression of Nox4 and Nox1. These results suggest that blood pressure and angiotensin II type 1 receptor activation are involved in the up-regulation of Nox1 and Nox4 expression, which could contribute to vascular injury during chronic hypertension. 相似文献
52.
The association of MTHFR and CBS variants with the doubling time and responsiveness to several chemodrugs was analyzed in 26 human cancer xenografts. The tumors homozygous for the absence of insertion (NN) for the CBS 844ins68bp were more chemosensitive than those with insertion (NI) to TS-1 (P=0.0048), suggesting a potential effect of this variant on fluoropyrimidine efficacy. Furthermore, the doubling time of tumors with a variant C allele (AC or CC) in MTHFR-A1298C was significantly longer than that of tumors with a normal allele (AA) (P=0.0008). Twenty-nine cellular proliferation-related genes were associated with MTHFR-A1298C genotyping and with the doubling time. 相似文献
53.
Hiromi Kataoka Takashi Joh Yusuke Inoue Naotaka Ogasawara Tadayuki Oshima Satoshi Tanida Makoto Sasaki Haruhisa Nakao Takahiro Nakazawa Hirotaka Ohara 《Digestive endoscopy》2006,18(4):294-297
A 75‐year‐old male was admitted to the gastroenterology unit of Nagoya City University Hospital due to epigastralgia after surgical treatment for right renal cancer. Endoscopy revealed advanced type 1 gastric cancer in the corpus of the stomach and multiple polypoid lesions in the stomach and duodenum. X‐ray examination of the small intestine using barium showed multiple polyps in the upper jejunum. Faint pigmentation on the palm was also detected. Peutz‐Jeghers syndrome (PJS) was diagnosed, despite a lack of family history. Total gastrectomy, resection of part of the upper jejunum and intraoperative endoscopic polypectomy of duodenal polyps was performed. This is the second reported case of PJS associated with renal cancer. We also detected a missense mutation in the tumor suppressor gene STK11 that, when mutated, is causative for PJS. 相似文献
54.
Shigeo Nakamura Takashi Koshikawa Tsuneko Sato Kayoko Hayashi Taizan Suchi 《Pathology international》1992,42(10):745-750
We describe a 54-year-old woman with primary pulmonary adenocarcinoma showing a characteristic papillary architecture and prominent cilia formation. Immunohistochemically, the tumor cells were positive for carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA) and Leu Ml, and negative for lactoferrin and surfactant apoprotein. An ultrastructural study also indicated differentiation toward bronchial surface epithelial cells. To our knowledge, this type of neoplasm has not been reported as peripheral-type adenocarcinoma of the lung. Acta Pathol Jpn 42: 745–750, 1992. 相似文献
55.
Yoshie Ochiai Kazuhiro Kurisu Takashi Kajiwara Hiroshi Kumeda Ryuji Tominaga 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(2):81-83
We describe a case of type B aortic dissection with large ascending aortic aneurysm occurring 12.8 years after aortic root
replacement (Cabrol procedure) in a non-Marfan patient with cystic medial necrosis of the aorta. We have successfully performed
an extended total aortic arch replacement using a four-branched graft through the “L-indsion” approach (a combination of a
left anterior thoracotomy and upper half median sternotomy). Of note, a histological specimen from the aneurysmal ascending
aortic wall revealed “healed aortic dissection” with fibrous tissue replacing the media and intima in addition to multiple
foci of cystic medial necrosis. 相似文献
56.
Y Moriyama Y Morishita H Toyohira S Shimokawa Y Umebayashi H Saigengi S Kawashima A Taira 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(7):538-542
Four patients with descending thoracic aortic aneurysm were successfully operated on under temporary bypass with an antithrombogenic tube and a Bio-Medicus centrifugal pump. The bypass flow ranged from 1.0 to 2.4 l/min with the mean femoral artery pressure of 50 to 70 mmHg. No complications such as paraplegia, hepatic dysfunction or renal failure were encountered in all the patients. Temporary increment of the serum amylase level occurred in all the patients, but any apparent clinical symptoms were not present. The temporary bypass method with an antithrombogenic tube and a centrifugal pump is useful and reliable for surgical treatment of descending thoracic aortic aneurysm. 相似文献
57.
Kimie Sai Takashi Umemura Atsuya Takagi Ryuichi Hasegawa Yuji Kurokawa 《Cancer science》1992,83(1):45-51
The roles of glutathione (GSH), cysteine, vitamin C., liposome-encapsulated superoxide dismutase (L-SOD) and vitamin E in preventing oxidative DNA damage and cytotoxicity in the rat kidney after administration of potassium bromate (KBrO3 ) to male F344 rats were investigated by measuring 8-hydroxydeoxyguanosine (8-OH-dG), an oxidative DNA product, lipid peroxidation (LPO) levels and relative kidney weight (RKW). Combined pre- and posttreatment of animals with 2 × 800 mg/kg GSH i.p. inhibited the increase of 8-OH-dG, LPO levels and RKW caused by 80 mg/kg KBrO3 i.p. administration. In contrast, pretreatment with 0.3 ml/kg diethylmaleate (DEM) i.p., a depletor of tissue GSH, was associated with elevation of 8-OH-dG, LPO levels and RKW after a 20 mg/kg KBrO3 i.p. treatment, which itself caused no change. Administration of KBrO3 itself reduced renal non-protein thiol levels, but this was inhibited by the two doses of exogenous GSH. Combined treatment with DEM and KBrO3 lowered the non-protein thiol level in the kidney more than did DEM treatment alone. Protective effects against the oxidative damage caused by KBrO3 were also observed for pre- and posttreatment with 400 mg/kg cysteine i.p., another sulfhydryl compound, and daily i.g. application of 200 mg/kg vitamin C for 5 days. However, no influence was evident after pre- and posttreatment with 18,000 U/kg L-SOD i.p. or daily i.g. 100 mg/kg of vitamin E for 5 days. The results suggest that intracellular GSH plays an essential protective role against renal oxidative DNA damage and nephrotoxicity caused by KBrO3 . 相似文献
58.
Reversible low-molecular-weight proteinuria in patients with distal renal tubular acidosis 总被引:2,自引:0,他引:2
Takashi Igarashi Hidehiko Kawato Shigehiko Kamoshita 《Pediatric nephrology (Berlin, Germany)》1990,4(6):593-596
Four patients with untreated renal tubular acidosis had a urinary excretion of low-molecular-weight (LMW) proteins which was restored to normal by alkali therapy. Hypokalaemic proximal tubular damage in untreated patients with distal renal tubular acidosis is believed to be the cause of LMW proteinuria. An examination of urinary excretion of LMW proteins is useful for determining hypokalaemic proximal tubular dysfunction, as well as the efficiency of alkali therapy. 相似文献
59.
Tetsumori Yamashima Takaomi C. Saido Masatoshi Takita Atsuo Miyazawa Jun Yamano Atsuo Miyakawa Hisashi Nishijyo Junkoh Yamashita Seiichi Kawashima Taketoshi Ono Tohru Yoshioka 《The European journal of neuroscience》1996,8(9):1932-1944
To clarify the mechanism of postischaemic delayed cornu Ammonis (CA)-1 neuronal death, we studied correlations among calpain activation and its subcellular localization, the immunoreactivity of phosphatidylinositol 4,5-bisphosphate (PIP2) and Ca2+ mobilization in the monkey hippocampus by two independent experimental approaches: in vivo transient brain ischaemia and in vitro hypoxia-hypoglycaemia of hippocampal acute slices. The CA-1 sector undergoing 20 min of ischaemia in vivo showed microscopically a small number of neuronal deaths on day 1 and almost global neuronal loss on day 5 after ischaemia. Immediately after ischaemia, CA-1 neurons ultrastructurally showed vacuolation and/or disruption of the lysosomes. Western blotting using antibodies against inactivated or activated μ-calpain demonstrated μ-calpain activation specifically in the CA-1 sector immediately after ischaemia. This finding was confirmed in the perikarya of CA-1 neurons by immunohistochemistry. CA-1 neurons on day 1 showed sustained activation of μ-calpain, and increased immunostaining for inactivated and activated forms of μ- and m-calpains and for PIP2. Activated μ-calpain and PIP2 were found to be localized at the vacuolated lysosomal membrane or endoplasmic reticulum and mitochondrial membrane respectively, by immunoelectron microscopy. Calcium imaging data using hippocampal acute slices showed that hypoxia-hypoglycaemia in vitro provoked intense Ca2+ mobilization with increased PIP2 immunostaining specifically in CA-1 neurons. These data suggest that transient brain ischaemia increases intracellular Ca2+ and PIP2 breakdown, which will activate calpain proteolytic activity. Therefore, we suggest that activated calpain at the lysosomal membrane, with the possible release of biodegrading enzyme, will cause postischaemic CA-1 neuronal death. 相似文献
60.
Yasuhiko Tamada Hiromichi Takama Toshihiko Ikeya Takashi Yokochi Hijiri Mori Yoshinari Matsumoto 《The Journal of dermatology》1995,22(12):913-916
Lewis Y (Ley) antigen, a difucosylated tetrasaccharide found on type 2 blood group oligosaccharides of glycolipids and glycoproteins, is thought to be a phenotypic marker predictive of cell differentiation. The distribution of this antigen in human anagen hair follicles was examined by immunohistochemical staining using a monoclonal antibody (AH-6) to Ley. In the bulbar and suprabulbar portion of anagen hair follicles, Ley antigen was detected in the three layers of the inner root sheath. Subsequently, the positive staining became translocated to the innermost layer of the outer root sheath in the middle part of the hair follicles. In the upper portion of the hair follicles, Ley antigen was found in the outer cells of the outer root sheath. These findings suggested that the expression of Ley antigen in the anagen hair follicles was correlated with the processes of keratinization or terminal differentiation. 相似文献