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1.
Kei Kamide Yoshihiro Kokubo Hironori Hanada Junko Nagura Jin Yang Shin Takiuchi Chihiro Tanaka Mariko Banno Yoshikazu Miwa Masayoshi Yoshii Tetsutaro Matayoshi Hisayo Yasuda Takeshi Horio Akira Okayama Hitonobu Tomoike Yuhei Kawano Toshiyuki Miyata 《Hypertension research》2006,29(4):243-252
Mutations in the gene encoding 11beta-hydroxysteroid dehydrogenase type 2, HSD11B2, cause a rare monogenic juvenile hypertensive syndrome called apparent mineralocorticoid excess (AME). In AME, defective HSD11B2 enzyme activity results in overstimulation of the mineralocorticoid receptor (MR) by cortisol, causing sodium retention, hypokalemia, and salt-dependent hypertension. Here, we have studied whether genetic variations in HDS11B2 are implicated in essential hypertension in Japanese hypertensives and the general population. By sequencing the entire coding region and the promoter region of HDS11B2 in 953 Japanese hypertensives, we identified five missense mutations in 11 patients (L14F, n = 5; R74H, n = 1; R147H, n = 3; T156I, n = 1; R335H, n = 1) and one novel frameshift mutation (4884Gdel, n = 1) in a heterozygous state, in addition to 19 genetic variations. All genetic variations identified were rare, with minor allele frequencies less than 0.005. Four of 12 patients with the missense/frameshift mutations showed renal failure. Four missense mutations, L14F, R74H, R147H, and R335H, were successfully genotyped in the general population, with a sample size of 3,655 individuals (2,175 normotensives and 1,480 hypertensives). Mutations L14F, R74H, R147H, and R335H were identified in hypertensives (n = 6, 8, 3, and 0, respectively) and normotensives (n = 8, 12, 5, and 0, respectively) with a similar frequency, suggesting that these missense mutations may not strongly affect the etiology of essential hypertension. Since the allele frequency of all of the genetic variations identified in this study was rare, an association study was not conducted. Taken together, our results indicate that missense mutations in HSD11B2 do not substantially contribute to essential hypertension in Japanese. 相似文献
2.
Yukiko Hasuike Takeshi Nakanishi Rintarou Moriguchi Yoshinaga Otaki Masayoshi Nanami Yasue Hama Miki Naka Koji Miyagawa Masaaki Izumi Yoshihiro Takamitsu 《Nephrology, dialysis, transplantation》2004,19(6):1474-1479
BACKGROUND: Cyanide is a toxic agent, and its detoxification product, thiocyanate, may be a major pathogenetic substance in uraemia. Recent studies examining the myeloperoxidase(MPO)/thiocyanate system have suggested a link between thiocyanate and atherosclerosis. However, inaccuracies in conventional assays for cyanide and thiocyanate have limited the understanding of their metabolism in haemodialysis (HD) patients. METHODS: We used high-performance liquid chromatography to measure cyanide in erythrocytes and thiocyanate in plasma in 43 HD patients and in a group of 46 healthy controls that included 15 current smokers. To clarify the metabolic conversion of cyanide to thiocyanate in uraemic patients, we also measured cysteine and sulfate. We then used stepwise regression analysis to analyse factors that determine erythrocyte cyanide and plasma thiocyanate. RESULTS: Mean cyanide and thiocyanate were significantly greater in HD patients than in non-smoking controls. However, cyanide was far below lethal concentrations in dialysis patients. Thiocyanate was six to seven times greater in HD patients than in non-smoking controls, and decreases in thiocyanate following dialysis were only 19.3+/-3.5%. Multiple regression analysis showed a positive correlation between cyanide and thiocyanate in controls, but a negative correlation in HD patients. In patients, an inverse relationship between thiocyanate and BUN was also observed. CONCLUSIONS: The elevation of thiocyanate in patients undergoing dialysis probably is secondary to both limited efficiency of HD and deranged metabolism of cyanide and thiocyanate. Because thiocyanate is a preferred substrate for MPO, it may play a role in uraemic complications including cardiovascular events. 相似文献
3.
Non-viral in vivo thrombomodulin gene transfer prevents early loss of thromboresistance of grafted veins. 总被引:1,自引:0,他引:1
Noriyuki Tabuchi Masayoshi Shichiri Aya Shibamiya Takatoshi Koyama Fumie Nakazawa Jihwa Chung Shinsaku Hirosawa Makoto Sunamori 《European journal of cardio-thoracic surgery》2004,26(5):995-1001
OBJECTIVE: Immediate loss of thrombomodulin activity in the endothelium of vein grafts has been demonstrated during 90 min exposure to arterial circulation; this loss of activity is ascribed as an important cause of early thrombosis. Conventional ex vivo gene transfection after vein harvest cannot cover this acute period immediately after implantation. We have established a highly efficient non-viral gene therapy protocol utilizing modified transferrin receptor-facilitated gene transfer. Using this technique, we examined whether in vivo thrombomodulin gene therapy, directed to the endothelium of rat veins 2 days prior to grafting, may prevent thromboresistance impairment of vein grafts under simulated arterial circulation. METHODS: Abdomen of SD rat was opened and cationic liposome:transferrin:thrombomodulin gene complexes or the vector without DNAs were applied to the inferior vena cava of rats while blood flow was reduced by proximal and distal clamping. After 2 days, the transfected veins were harvested and thrombomodulin expression and thromboresistance properties determined before and after exposure to an artificial circuit. RESULTS: The trial of gene transfection using variable doses of DNAs confirmed that 7.5 microg of total DNAs was the most efficient quantity for thrombomodulin gene transfection to IVCs, although accompanying an increase of gene expression in other downstream organs. By transfection of the thrombomodulin gene in IVCs, the generation capacity of activated protein C in venous endothelium increased three-fold compared with veins treated with vector alone (P<0.01). Under simulated arterial circulation, perfusion of veins treated with vector alone decreased thrombomodulin activity to 36% of preperfused levels (P<0.01), whereas transfected grafts preserved the activity at normal vein endothelium levels even after perfusion. Consequently, the increase in endothelial thrombin activity induced by simulated arterial circulation was markedly attenuated in transfected veins (P<0.01), while immunohistochemistry confirmed the preservation of endothelial lining. CONCLUSIONS: Transferrin receptor-facilitated in vivo gene transfer to the inferior vena cava resulted in sufficient thrombomodulin gene expression immediately after graft implantation and subsequent maintenance of thromboresistance even after exposure to arterial pressure. Although further studies are needed, the present results suggest the possibility of gene therapy targeting acute phases of vein graft disease. 相似文献
4.
Masayoshi Tachibana Norio Yasuda Masaki Yoshimatsu Hideo Nishimura Osamu Mizukoshi 《Cancer chemotherapy and pharmacology》1987,19(1):65-68
Summary UFT, a combination of the masked compound of 5-fluorouracil (FT-207) and uracil, was given to head and neck cancer patients for 1 week preoperatively and for 8 weeks postoperatively. Drug concentrations were examined in the surgically removed tissues. The concentrations of FT-207, 5-fluorouracil, and uracil were higher in tumor tissues than in normal tissues. The lymphocyte subpopulations were assessed by cytofluorometry with monoclonal antibodies. There was no evidence that adjuvant chemotherapy with UFT specifically suppresses immunocompetent cells. We therefore conclude that further clinical evaluation of adjuvant chemotherapy with UFT would be worthwhile. 相似文献
5.
Preliminary results of intermittent retrograde cerebral perfusion during proximal aortic arch surgery. 总被引:1,自引:0,他引:1
Shinpei Yoshii Okihiko Akashi Masahiro Kobayashi Atsuo Kojima Samuel J K Abraham Shunya Shindo Yusuke Tada Hiroji Higuchi 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(11):588-593
OBJECTIVE: Continuous retrograde cerebral perfusion during aortic arch surgery is associated with cerebral edema. In this report, we describe the clinical use of a new type of intermittent retrograde cerebral perfusion. SUBJECTS AND METHODS: Fourteen patients with a Stanford type A dissection were included in this study. With the usual method of retrograde cerebral perfusion, about 2,500 mL venous blood is drained from bicaval cannulae into a hard-shell reservoir, and oxygenated blood is perfused through the superior vena caval cannula. The flow rate is 300 mL/min. After about 15 min, retrograde perfusion is discontinued, and drainage from the bicaval cannulae is restarted. When a bloodless field is necessary, perfusion also is discontinued. RESULTS: Two to seven cycles of intermittent retrograde cerebral perfusion were administered (average, 3.1+/-0.4, mean+/-SD). The total retrograde perfusion time was 36.0+/-1.9 min which was equivalent to 74.8% of the circulatory arrest time. No patient developed edema of the upper body. The time to wake-up was 3 to 14 h (average, 6.5+/-1.0 h). No patient suffered any neurologic complications even though the time of circulatory arrest was greater than 60 min in four cases. Head magnetic resonance imaging or computed tomography was performed in 12 cases, and no evidence of hypoxic brain injury was detected. CONCLUSIONS: Our clinical experience using a moderate amount of intermittent retrograde cerebral perfusion is superior to continuous retrograde cerebral perfusion for protecting the brain during aortic arch surgery. 相似文献
6.
Michio Kimura Kayoko Kurosawa-Ohsawa Mikiko Takahashi Masayoshi Koyama Shigeaki Tanaka Tetsuro Matsuishi 《Thrombosis research》1992,67(6):687-696
Ca(++)-dependent monoclonal antibody specific to gamma-carboxyglutamic acid (Gla) domain of protein C was produced. It did not cross-react to the other vitamin K-dependent plasma proteins but to protein C of the other species. Using this monoclonal antibody, PC01, rabbit (170 micrograms), rat (60 micrograms) and mouse (40 micrograms) protein Cs were isolated from 100 ml of their plasma by affinity chromatography. All of these protein Cs were two chain form linked by disulfide bond as well as human protein C and activated by thrombin-thrombomodulin complex. Rat and mouse protein Cs showed similar characters to human protein C. On the other hand rabbit protein C had different M(r) of heavy and light chains and showed lower anticoagulant activity compared with human protein C. 相似文献
7.
S Yoshii T Fuzii T Saitoh R Yamamoto N Ishida Y Hosoi M Tahara 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1992,83(3):374-382
Thirty-five patients with benign prostatic hyperplasia (age range: 45-88 years; average: 67.5 years) underwent local thermotherapy with prostathermer. Clinical therapeutic effect was evaluated in 30 of the 35 patients: 2 patients interrupting from therapy and 3 receiving pretherapeutic indwelling catheters were not included. A total of 6 treatments (2 per week) were performed, each lasting for 60 minutes. As for subjective improvement, improvement of nocturia was noted in 70.0% of all patients and sense of residual urine in 70.7%. Post-therapeutic nocturnal and daytime decreases in urination frequency were statistically significant (p less than 0.01). Objective improvement in residual urine volume occurred in 19 of the 30 cases, and elevation in uroflowmetric maximal flow rate following therapy was statistically significant (p less than 0.05). Among complications ascribable to catheter insertion were urethral bleeding (3 cases), epididymitis (1 case) and pyuria (1 case). Therapeutic result based primarily on subjective symptoms and partly on objective findings was fairly good in 17 cases (about 57%), and slightly good in 25 cases (about 83%). In conclusion, this therapy seems to be useful in the treatment of benign prostatic hyperplasia. 相似文献
8.
Masayoshi Hamawaki Motoharu Narimatsu Hiroshi Yamaguchi Katsuo Nishi Kiyoyuki Eishi 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(3):110-112
A 10-year-old girl having bilateral subclavian steal associated with severe coarctation of the thoracic aorta and an aberrant
right subclavian artery was found, on admission, to have no difference between upper and lower extremity blood pressure, but
echocardiography revealed severe thoracic aorta coarctation and systolic blood pressure in the carotid arteries exceeding
200 mmHg estimated by Doppler ultrasonography. Magnetic resonance imaging and angiography demonstrated bilateral subclavian
steal without esophageal compression. We reconstructed the aortic arch using the left subclavian artery and a reversed Blalock-Park
procedure, then repaired the coarctation with a 14 mm woven double velor vascular graft. The girl was symptom-free following
uncomplicated recovery from surgery. Doppler ultrasonography 2 weeks after surgery showed the pressure gradient across the
aortic arch had decreased from 180 mmHg to 60 mmHg. This residual gradient at the anastomosis between the ascending aorta
and left subclavian artery may improve as native vessels grow. 相似文献
9.
Seiya Kikuchi Akira Ingu Masayoshi Ito 《Annals of thoracic and cardiovascular surgery》2005,11(5):320-323
We report an 18-month-old boy with the association of pectus excavatum and tetralogy of Fallot (TOF). We successfully performed simultaneous pectus repair using sternal elevation without any prosthetic support and total correction of TOF after a prior modified Blalock-Taussig shunt. Retracting a divided costo-sternal complex with a rectus abdominal flap away from the operative field before the cardiac operation provided excellent surgical exposure. The modified Blalock-Taussig shunt prior to the combined repair prevented life-threatening hypoxic spells during dissection of the deformed sternum and costochondral cartilages before institution of cardiopulmonary bypass. 相似文献
10.
Masayoshi Johno Munashi Oishi Masahiro Kohmaru Kohji Yoshimura Tomomichi Ono 《The Journal of dermatology》1994,21(3):197-204
A boy with skin eruptions resembling varicella and specific for Langerhans cell histiocytosis (LCH) is reported. At his initial visit when he was four months old, vesiculopustular lesions were present over the entire body; these had first appeared on the third day post partus. Histopathological, immunohistochemical, and electron microscopical examination confirmed the Langerhans cell phenotype and Birbeck granules in the responsible cells. He also had hydronephrosis, recurrent fever, and cutaneous bacterial infections. His parents refused further medical treatment and he died of diarrhea with cachexia about two years later. LCH may present diagnostic difficulties by manifesting as a skin eruption which resembles varicella. 相似文献