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991.
Zamora CA Sugimoto K Tsurusaki M Yamaguchi M Izaki K Taniguchi T Iwama Y Mimura F Sugimura K 《Journal of vascular and interventional radiology : JVIR》2004,15(8):875-879
A patient with portosystemic encephalopathy, hyperammonemia, and a spontaneous splenorenal shunt was admitted to the authors' institution after a failed attempt at transvenous retrograde shunt obliteration. As an alternative approach, the authors separated splenic and portal flows by embolizing only the proximal splenic vein while leaving the shunt intact. Thus, the splenic flow could escape into the systemic circulation and an extreme increase in portal pressure was avoided. The procedure could provide rapid decreases in blood ammonia levels and a fast resolution of symptoms, but repeated interventions were required. 相似文献
992.
Heterogeneity of cerebral blood flow in frontotemporal lobar degeneration and Alzheimer’s disease 总被引:4,自引:1,他引:3
Nagao M Sugawara Y Ikeda M Fukuhara R Hokoishi K Murase K Mochizuki T Miki H Kikuchi T 《European journal of nuclear medicine and molecular imaging》2004,31(2):162-168
This study was designed to quantify the heterogeneity on cerebral blood flow single-photon emission tomography (SPET) images in frontotemporal lobar degeneration (FTLD) and Alzheimers disease (AD) using a three-dimensional fractal analysis. Twenty-one FTLD patients, 21 AD patients and 11 healthy controls underwent technetium-99m hexamethylpropylene amine oxime SPET scanning. Patients with FTLD and AD matched for sex, age and the severity of dementia as estimated with the Clinical Dementia Rating and were determined to be in the early stage of illness. We delineated the SPET images using a 35% cut-off and a 50% cut-off of the maximal voxel radioactivity and measured the number of voxels included in the contours of two different cut-offs. The fractal dimension (FD) was calculated by relating the logarithms of the cut-offs and the numbers of voxels, and it was defined as the heterogeneity of the cerebral perfusion. We divided the SPET images into two sets, anterior and posterior, with equal numbers of coronal SPET slices. We calculated total FD, anterior FD and posterior FD for total, anterior and posterior SPET images. Anterior FDs for FTLD and AD were 1.55±0.34 and 1.24±0.19 (P=0.0002). The ratios of anterior to posterior FD for FTLD and AD were 1.81±0.41 and 1.32±0.14 (P<0.0001). Use of the anterior FD and the ratio of anterior to posterior FD separated FTLD patients from AD patients and controls with a sensitivity of 85.7% and a specificity of 93.8%. Anterior FD and the ratio of anterior to posterior FD may be useful in distinguishing FTLD from AD. 相似文献
993.
Masumoto K Takahashi Y Nakatsuji T Arima T Kukita J 《Asian journal of surgery / Asian Surgical Association》2004,27(3):238-240
Cow's milk allergic enterocolitis is a common paediatric gastrointestinal disease. However, radiological findings from contrast studies have rarely been reported. We report two Japanese neonate patients with cow's milk allergic enterocolitis with vomiting, bloody stool and unique findings on upper gastrointestinal contrast study. Upper gastrointestinal contrast study showed folds of the small intestine to be thickened, such as in spasm, or ribbon-like cords in both cases. There was also poor passage from the duodenum to the jejunum in one case. In addition, there were spastic findings on lower gastrointestinal contrast study in part of the large colon in one case. Clinicians, including paediatric surgeons, treating neonates with bloody stool and/or vomiting should thus be aware that unique findings on upper and lower gastrointestinal contrast studies may be useful in suspecting cases with cow's milk allergic enterocolitis. 相似文献
994.
Yoshida K Kitauchi T Yoneda T Kimura S Takao M Ishibashi M Hirao Y Kikkawa K 《Clinical and experimental nephrology》2004,8(2):155-159
Post-transplantation renal artery stenosis is recognized at relatively early periods after renal transplantation. We report herein our experience of utilizing transluminal expanded metal stents (Palmaz stent and Wall stent) for post-transplantation renal artery stenosis, and monitoring with intravascular ultrasound (IVUS) imaging. The recipients were a 51-year-old woman (case 1) and a 57-year-old man (case 2), and the grafts were procured from cadaveric donors. Renal function had deteriorated suddenly at 5 months after renal transplantation in case 1 and at 86 months in case 2. The cause of the graft dysfunction was renal arterial stenosis. Color doppler ultrasound imaging and angiography diagnosed post-transplantation renal artery stenosis. The renal artery stenosis was serious, being greater than 90% in both patients. Percutaneous transluminal angioplasty (PTA) was performed, but its effectiveness was not sufficient; therefore, an indwelling endoluminal metallic Palmaz stent and an indwelling Wall stent were placed at the sites of stenosis while monitoring was done with IVUS. No complications were recognized at all. The length and degree of stenosis location became clear by using IVUS, and suitable stents could be selected for the renal artery stenosis. The clinical effect was excellent; the renal function improved to the pre-hospitalization value. We conclude that the Palmaz stent and the Wall stent were useful as a noninvasive strategy for treating post-transplantation renal artery stenosis. This procedure could be performed safely and surely using IVUS. 相似文献
995.
Histone deacetylase inhibitor FK228 activates tumor suppressor Prdx1 with apoptosis induction in esophageal cancer cells. 总被引:2,自引:0,他引:2
Isamu Hoshino Hisahiro Matsubara Naoyuki Hanari Mikito Mori Takanori Nishimori Yasuo Yoneyama Yasunori Akutsu Haruhito Sakata Kazuyuki Matsushita Naohiko Seki Takenori Ochiai 《Clinical cancer research》2005,11(21):7945-7952
PURPOSE: The histone deacetylase inhibitor FK228 shows strong activity as a potent antitumor drug but its precise mechanism is still obscure. The purpose of this study is to reveal the effect of FK228 on gene expression in the cell and to determine the mechanism of the antitumor activity of FK228 for further clinical applications. EXPERIMENTAL DESIGN AND RESULTS: Microarray analysis was applied to verify the gene expression profiles of 4,608 genes after FK228 treatment using human esophageal squamous cell cancer cell lines T.Tn and TE2. Among them, peroxiredoxin 1 (Prdx1), a member of the peroxiredoxin family of antioxidant enzymes having cell growth suppression activity, as well as p21(WAF1), were significantly activated by FK288. In addition, FK228 strongly inhibited the cell growth of T.Tn and TE2 by the induction of apoptosis. Further, chromatin immunoprecipitation analysis revealed that FK228 induced the accumulation of acetylated histones H3 and H4 in Prdx1 promoter, including the Sp1-binding site. In mouse xenograft models of T.Tn and TE2 cells, FK228 injection resulted in significant tumor regression as well as activated Prdx1 expression in tumor tissues. Prdx1 suppression by RNA interference hindered the antitumor effect of FK228. CONCLUSION: Our results indicate that the antitumor effect of FK228 in esophageal cancer cells is shown at least in part through Prdx1 activation by modulating acetylation of histones in the promoter, resulting in tumor growth inhibition with apoptosis induction. 相似文献
996.
Hiroaki Kajiyama Kiyosumi Shibata Mikio Terauchi Takanori Morita Kazuhiko Ino Shigehiko Mizutani Fumitaka Kikkawa 《Clinical cancer research》2005,11(5):1798-1808
Recently, numerous studies have shown that endothelin-1 (ET-1) is expressed in ovarian carcinoma and that ET-1 selectively acts as an autocrine or paracrine growth factor through the endothelin A receptor (ET(A)R), and is involved in cell proliferation, invasiveness, neovascularization, and prevention of apoptosis. Neutral endopeptidase 24.11 (NEP) is a cell surface aminopeptidase with a ubiquitous expression and is capable of degrading a number of bioactive peptides including ET-1. Our previous report showed that stromal NEP expression in ovarian carcinoma was down-regulated as the histologic grade advanced. Here, we confirmed that NEP was expressed in tumor cells as well as stromal tissues in ovarian carcinoma, and investigated the functions of NEP in this carcinoma. We showed that there was a significant decrease in cell proliferation and invasiveness with a reduction in the concentration of ET-1 in the conditioned medium on the NEP overexpression of NEP in ovarian carcinoma cells. In addition, the overexpression of NEP enhanced susceptibility to paclitaxel, resulting in an increased occurrence of apoptotic morphologic change. Furthermore, tumorigenesis was reduced in vivo with the overexpression of NEP, down-regulation of both matrix metalloproteinase-2, and vascular endothelial growth factor expression. This evidence suggests that NEP functionally suppresses the progression of ovarian carcinoma and further study of this enzyme may reveal an effective way to target ET-1 for the treatment of this carcinoma. 相似文献
997.
Arata Horii Takanori Saika Atsuhiko Uno Suetaka Nishiike Kenji Mitani Masato Nishimura Tadashi Kitahara Munehisa Fukushima Aya Nakagawa Chisako Masumura Tomo Sasaki Kaoru Kizawa Takeshi Kubo 《Otology & neurotology》2006,27(6):896-900
OBJECTIVE: To look for factors relating to the vertigo control and hearing changes after intratympanic injections of gentamicin (GM). STUDY DESIGN: Prospective. SETTING: Tertiary referral medical center. PATIENTS: Twenty-eight patients with intractable Ménière's disease. INTERVENTIONS: Three intratympanic injections of GM (once per day for three consecutive days). MAIN OUTCOME MEASURES: Although five patients needed further GM injections or vestibular neurectomy because of poor control (Group I), 23 patients had their vertigo controlled for more than two years without further treatment (Group II). The number of vertigo spells per month, pure-tone audiometry, electrocochleography, caloric response, post-head shake nystagmus, and plasma vasopressin as a stress marker were examined. RESULTS: Before GM injections, there was no difference in the number of vertigo spells per month between Groups I and II. However, the hearing thresholds were higher in Group I. Hearing improvement, increase in percentage of canal paresis and induction of post-head shake nystagmus were observed after GM injections only in Group II. Even in the 11 patients who showed an improvement in hearing of more than 10 dB (hearing improvement group), percentage of canal paresis was increased after GM. More, premedication plasma vasopressin levels were lower in the hearing improvement group as compared with the hearing loss/no changes group. Four of eight patients became negative for dominant negative summating potential in electrocochleography after GM injections in the hearing improvement group. CONCLUSION: Our data indicate that the frequency of vertigo is not a key factor in the vertigo control after GM injections, that induction of vestibular damage in the injected ear is essential for the control of vertigo and this effect is mostly pronounced in patients with milder hearing loss, and that hearing improvement is not only a consequence of good vertigo control but also affected by the stress level before treatment. 相似文献
998.
Effects of single low dose irradiation on subventricular zone cells in juvenile rat brain 总被引:5,自引:0,他引:5
Amano T Inamura T Wu CM Kura S Nakamizo A Inoha S Miyazono M Ikezaki K 《Neurological research》2002,24(8):809-816
Although the juvenile human brain is relatively radioresistant, irradiation can result in brain growth retardation, progressive mental disturbance, and neurologic abnormalities. As neural stem cells or progenitor cells may be a target of radiation injury and may play an important role in the brain's functional recovery, we examined the effects of whole brain irradiation on these cells in juvenile rat. Six-week-old Wistar rats, where the brain is still growing, were irradiated with single doses of 1, 2, or 3 Gy X-ray. We measured their body and brain weights at 30 or 60 days after irradiation. The chronological changes of the subventricular zone (SVZ) were examined at 6 h, 2, 7, 14, 30, or 60 days after irradiation by immunohistochemistry, specifically looking at the neural stem cells or progenitor cells using anti-nestin antibodies specific for these cells. The rate of brain weight gain of irradiated rats significantly decreased in comparison to controls, although that of body weight gain was similar among them. Multiple apoptotic cells appeared in the SVZ at 6 h after irradiation with simultaneous reduction in nestin-positive cells (69% of the control). The cell levels recovered within a week, with the nestin-positive cells reaching maximal numbers (182%) on Day 14. Nestin-positive cells returned to baseline levels within 30 days (96%) and remained unchanged for the subsequent 60 days. The X-ray dosage did not affect these findings. Our findings revealed that single low dose X-ray administration reversibly affected the levels of neural stem and progenitor cells in the SVZ region. These results suggest that continuous multiple administrations of X-rays in clinical treatment may affect irreversible changes on neural stem or progenitor cells, causing brain growth retardation, or dysfunction. 相似文献
999.
Type V phosphodiesterase expression in cerebral arteries with vasospasm after subarachnoid hemorrhage in a canine model 总被引:4,自引:0,他引:4
Cyclic GMP (cGMP) mediates smooth muscle relaxation in the central nervous system. In subarachnoid hemorrhage (SAH), decreases in intrinsic nitric oxide (NO) cause cerebral vasospasms due to the regulation of cGMP formation by NO-mediated pathways. As phosphodiesterase type V (PDE V) selectively hydrolyzes cGMP, we hypothesized that PDE V may function in the initiation of vasospasm. This study sought to identify the altered PDE V expression and activity in the vasospastic artery in a canine SAH model. We also used this system to examine possible therapeutic strategies to prevent vasospasm. Using a canine model of SAH, we induced cerebral vasospasm in the basilar artery (BA). Following angiographic confirmation of vasospasm on day 7, PDE V expression was immunohistochemically identified in smooth muscle cells of the vasospastic BA but not in cells of a control artery. The isolation of PDE enzymes using a sepharose column confirmed increased PDE V activity in the vasospastic artery only through both inhibition studies, using the highly selective PDE V inhibitor, sildenafil citrate, and Western blotting. Preliminary in vivo experiment using an oral PDE V inhibitor at 0.83 mg kg(-1) demonstrated partial relaxation of the spastic BA. PDE V activity was increased from control levels within the BA seven days after SAH. PDE V expression was most prominent in smooth muscle cells following SAH. These results suggest that clinical administration of a PDE V inhibitor may be a useful therapeutic tool in the prevention of vasospasm following SAH. 相似文献
1000.
Iwasaki H Inoue H Mitsuke Y Badran A Ikegaya S Ueda T 《The Journal of laboratory and clinical medicine》2002,140(6):382-386
Evidence for nonantibiotic activity displayed by tetracycline has been extensively reported in the field of antiinflammation. Here, we report a growth-inhibitory effect of doxycycline on CCRF-CEM, a T-lymphoblastic human leukemic cell line. Cells were incubated with doxycycline at concentrations ranging from zero to 50 micromol/L. We examined the hypothesis that induction of apoptosis is one of the mechanisms by which doxycycline inhibits CCRF-CEM proliferation. Caspase-3 activity of cells grown in the presence of 10 micromol/L and 50 micromol/L doxycycline increased dose-dependently after 24 hours in culture. The demonstration that doxycycline induces APO 2.7 expression in CCRF-CEM cells in vitro also supports its capacity for induction of apoptosis. The level of matrix metalloproteinase-2 was significantly lower in the medium cultured with 50 micromol/L doxycycline than the control. These phenomena suggest that this well-tolerated oral agent has the potential to be of value in antileukemic therapy. 相似文献