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991.
Nishimoto H Wada T Kuroda K Yoshida Y Okuguchi T Ogasawara K Ogawa A Hiraga M Takahashi A 《No shinkei geka. Neurological surgery》2003,31(3):297-301
We report a case of the development of cavum septi pellucidi and cavum Vergae after head trauma in a 29-year-old female patient. After the accident, cavum septi pellucidi and cavum Vergae gradually expanded. Using magnetic resonance imaging, we followed up the patient for 33 months after the head trauma. Preoperatively, metrizamide CT cisternography was performed in order to investigate CSF flow between the cavum septi pellucidi/cavum Vergae and the subarachnoid space. Using neuroendoscopy, we succeeded in opening the wall of the cavum septi pellucidi via anterior horn of the right lateral ventricle. Cystography was performed during the operation. The volume of the cavum septi pellucidi/cavum Vergae decreased remarkably. In this case, our CSF flow studies revealed that CSF flowed into the posterior part of the cavum Vergae from the third ventricle and did not flow backward to the third ventricle. Therefore, we considered that the development of cavum septi pellucidi/cavum Vergae was related to a one-way valve mechanism between the posterior part of the cavum Vergae and the third ventricle. 相似文献
992.
Facial linear scars with concave and erythematous appearance sometimes occur after long observation even if adequate conservative treatments have been applied. Because the regenerated epithelium is thin, those scars are seen as red or pink, and are sometimes accompanied with postinflammatory hyperpigmentation. For these scars, flashlamp-pumped pulsed dye of the wavelength of 585 nm and pulse-width of 450 µs was used, and acceptable results were obtained. Three cases required one treatment and one case needed two, and any side effects were not recognized. Compared with the carbon dioxide laser, which often shows severe scarring as a side effect, the pulsed dye laser with a short down time is useful. 相似文献
993.
Uchida K Arakawa Y Ohyama K Sirakawa M Tsuji R Yokoyama M Imataka K Sato M Shimizu Y 《Neurologia medico-chirurgica》2003,43(7):356-359
A 40-year-old female presented with growth hormone (GH)-secreting pituitary adenoma associated with primary moyamoya disease manifesting as amenorrhea, acromegaly, and transient ischemic attack. Magnetic resonance (MR) imaging revealed a tumor mass extending from the sella turcica to the suprasellar cistern, and MR angiography demonstrated stenoses in the bilateral internal carotid arteries with basal moyamoya vessels. Her blood GH and insulin-like growth factor (IGF-1) levels were elevated to 78.94 and 923.0 ng/ml, respectively. The patient underwent removal of the pituitary adenoma because her ischemic symptoms disappeared after oral aspirin medication. Subtotal resection resulted in persistence of the high blood GH and IGF-1 levels. Postoperative MR angiography showed progression of the stenoses in the bilateral internal carotid arteries. Excess systemic GH and IGF-1 may participate in the progression of vascular disease and so could have caused the deterioration of the moyamoya disease. 相似文献
994.
Renal involvement in children with influenza A virus infection 总被引:2,自引:0,他引:2
Watanabe T Yoshikawa H Abe Y Yamazaki S Uehara Y Abe T 《Pediatric nephrology (Berlin, Germany)》2003,18(6):541-544
Renal involvement in influenza A virus infection has been rarely reported. To define the clinical characteristics and the factors contributing to the development of renal involvement in influenza A virus infection, we reviewed the clinical characteristics, laboratory data, pediatric risk of mortality (PRISM) score, and the number of systemic inflammatory response syndrome (SIRS) criteria and dysfunctional organs in 45 hospitalized children with influenza A virus infection. Eleven (24.4%) patients had renal involvement. All patients with renal involvement suffered from sepsis and multiple organ dysfunction syndrome (MODS) and 5 developed acute renal failure (ARF). The incidences of dehydration, hypotension, disseminated intravascular coagulation (DIC), and rhabdomyolysis were significantly higher in patients with renal involvement. PRISM scores, the numbers of SIRS criteria and dysfunctional organs, and mortality rate were also higher in patients with renal involvement. Influenza A RNA was absent in the renal tissues of 3 patients with ARF. These results suggested that renal involvement in influenza A virus infection occurred in patients with sepsis and MODS; dehydration, hypotension, DIC, and rhabdomyolysis were factors contributing to its development; direct viral injury to the kidney did not seem to occur in influenza A virus infection. 相似文献
995.
Proliferation of vascular smooth muscle cells stimulated by reactive oxygen species (ROS) may play a pivotal role in the pathogenesis of atherosclerosis. To clarify mechanisms by which ROS promote vascular atherogenesis, effects of fluvastatin, amlodipine, ozagrel (thromboxane synthetase inhibitor), GF109203X (a protein kinase C inhibitor) and Y27632 (a ROCK inhibitor) on the proliferation of guinea-pig basilar artery smooth muscle cells (GBa-SM3) in a 5% FBS culture medium were studied over 3 d in the presence or absence of a free radical scavenger, edaravone. Viability of cells at the end of incubation was measured by the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) test. Results demonstrated that fluvastatin and amlodipine by themselves possess antiproliferative effects on the GBa-SM3 cells at 10-100 microM and 0.1-1 microM, respectively. While edaravone possessed no antiproliferative effect by itself at 100 microM, it significantly (p<0.05) augmented the antiproliferative effects of fluvastatin and amlodipine. In addition, ozagrel, GF109203X and Y27632 possessed no appreciable effects on the cell growth by themselves. However, coincubation of edaravone at 100 microM with these agents elicited significant antiproliferative effects for ozagrel, GF109203X and Y27632 at 10-100 microM, 1-10 microM and 0.1-1 microM, respectively. In conclusion, edaravone may have clinically beneficial interactions with fluvastatin, amlodipine and ozagrel regarding the prevention of vascular atherosclerosis. The interactions between edaravone and the inhibitors of protein kinase C and ROCK were suggestive of possible contributions of ROS-triggered intracellular signals associated with these enzymes to vascular atherogenesis, but further studies are required for confirmation. 相似文献
996.
Pulmonary gene delivery by chitosan-pDNA complex powder prepared by a supercritical carbon dioxide process 总被引:3,自引:0,他引:3
Okamoto H Nishida S Todo H Sakakura Y Iida K Danjo K 《Journal of pharmaceutical sciences》2003,92(2):371-380
Chitosan-plasmid DNA (pDNA) complex powders as a pulmonary gene delivery system were prepared with a supercritical carbon dioxide (CO(2)) process and their in vivo activity was evaluated. The powders with mannitol as a carrier were prepared by dispersing aqueous solutions of a luciferase expression plasmid driven by the cytomegalovirus promoter (pCMV-Luc) with or without chitosan as a cationic vector in a supercritical CO(2)/ethanol admixture. The supercritical CO(2) process with a V-shaped nozzle successfully produced chitosan-pDNA powders. The addition of chitosan suppressed the degradation of pCMV-Luc during the supercritical CO(2) process and increased the yield of powders. The luciferase activity in mouse lung was evaluated after pulmonary administration of the powders or pCMV-Luc solutions. The chitosan-pDNA powders increased the luciferase activity in mouse lung compared with pCMV-Luc powders without chitosan or pCMV-Luc solutions with or without chitosan. The chitosan-pDNA powder with an N/P ratio = 5 increased the luciferase activity to 2700% of that of the pCMV-Luc solution. These results suggest that gene powder with chitosan is a useful pulmonary gene delivery system. 相似文献
997.
Evidence for the involvement of GABA(A) receptor blockade in convulsions induced by cephalosporins 总被引:8,自引:0,他引:8
Sugimoto M Uchida I Mashimo T Yamazaki S Hatano K Ikeda F Mochizuki Y Terai T Matsuoka N 《Neuropharmacology》2003,45(3):304-314
There is accumulating evidence that most beta-lactam antibiotics (i.e., cephalosporins and penicillins) have some degree of convulsive activity, both in laboratory animals as well as in clinical settings. The proposed mechanism is suppression of inhibitory postsynaptic responses, mainly mediated by gamma-amino butyric acid (GABA)(A)-receptors (GABA(A)-R). However, comprehensive studies on the convulsive activities of various beta-lactam antibiotics in vivo and in vitro have not been performed. We have therefore examined the convulsive activities of seven different cephalosporins using both in vivo and in vitro models: intracerebroventricular (ICV) administration in mouse; [(3)H]muscimol binding assay (BA) in mouse brain synaptosome; and inhibition of recombinant mouse alpha1beta2gamma2s GABA(A)-Rs in Xenopus oocyte (GR). The rank orders of convulsive activities in mouse (cefazolin>cefoselis>cefotiam>cefpirome>cefepime>ceftazidime>cefozopran) correlated with those of inhibitory potencies on [(3)H]muscimol binding and GABA-induced currents of GABA(A)-R in vitro, with correlation coefficients of ICV:GR, ICV:BA and BA:GR of 0.882, 0.821 and 0.832, respectively. In contrast, none of the antibiotics had affinities for N-methyl-D-aspartate (NMDA) receptors nor facilitatory actions on NMDA receptor-mediated current in oocytes. These results clearly demonstrate that the mechanism of cephalosporin-induced convulsions is mediated predominantly through the inhibition of GABA(A)-R function and not through NMDA receptor modulation. 相似文献
998.
Antimicrobial activity of hinokitiol (beta-thujaplicin), which is a major component of the essential oil of Chamaecyparis obtuse, against Legionella pneumophila was investigated experimentally. The quantitative antibacterial assay of hinokitiol was carried out by the disk-diffusion method. The test concentrations of hinokitiol were 0.39 to 25.0 micrograms/disk, and the lowest concentrations of hinokitiol that showed growth inhibition against L. pneumophila were 1.56 micrograms/disk on B-SYE agar and 0.39 microgram/disk on B-SYE agar without iron. 相似文献
999.
Takahashi H Kaku K Tanaka T Uchida Y 《[Nihon kōshū eisei zasshi] Japanese journal of public health》2003,50(2):130-135
PURPOSE: To investigate zoonosis and vector surveillance systems in major countries, conducted by quarantine, health and environment authorities, and compare the results with the current Japanese systems. METHODS: We elaborated a questionnaire for zoonosis and vector surveillance systems regarding target diseases, vectors, period and area of operation, type of surveillance (active and/or positive), and feedback mechanisms which was then mailed to ten countries having strong trade and tourism links with Japan. We visited some authorities for further discussions. RESULTS: Eight countries which responded answered that all were conducting zoonosis and vector surveillance. Target diseases included those designated by the International Health Regulations and others with a higher priority for control and prevention in the individual countries. The type of surveillance was classified as: regular monitoring of the vector population, active detection of pathogens in vectors during a specific time period of a year, and intensive pathogen characterization when problems occurred. CONCLUSIONS: The significance of zoonosis and vector surveillance was recognized through this investigation, where we found differences in target diseases, and type of operation. The results should be utilized for generation of more useful and efficient surveillance systems in Japan. 相似文献
1000.
Hakura A Suzuki S Sawada S Sugihara T Hori Y Uchida K Kerns WD Sagami F Motooka S Satoh T 《Regulatory toxicology and pharmacology : RTP》2003,37(1):20-27
The purpose of the present study was to examine the inter-individual variation in the mutagenicity of chemicals using a variety of human S9 fractions. For this purpose, three procarcinogens, 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), benzo[a]pyrene (BP), and dimethylnitrosamine (DMN), were selected for the Ames test and their mutagenicity was examined using human liver S9 fractions prepared from 18 different donors and one pooled liver S9 fraction prepared from 15 different donors. In addition, rat S9 fraction prepared from male rats pretreated with phenobarbital and 5,6-benzoflavone (PB/BF) was used as reference in order to examine the mutagenic differences between human and rat (PB/BF) S9 fractions. The data demonstrate a large inter-individual diversity in the mutagenic response to procarcinogens. The mutagenicity of IQ and BP in the presence of a human liver S9 fraction (lot HLS-014) was equal to that observed in the presence of rat (PB/BF) S9 fraction. The mutagenicity of IQ and BP in the presence of a pooled human liver S9 fraction was lower (90 and 95%, respectively) than that observed in the presence of rat (PB/BF) S9. On the contrary, the mutagenicity of DMN in the presence of either a selected human liver S9 fraction (lot HLS-014) or pooled fraction was 8-fold higher than that found in the presence of rat (PB/BF) S9 fraction. Human liver S9 fraction (lot HLS-014) had one of the highest cytochrome P450 enzyme activities among the 18 different donors and higher than the pooled human liver S9 fraction. These results suggest that the use of both selected human liver S9 fractions with high metabolic activity (e.g., lot HLS-014 as used in this study) and a pooled S9 fraction with moderate metabolic activity could be used as a means to evaluate the inter-individual variability in mutagenic response to chemicals and to confirm positive responses from studies completed with rodent S9. 相似文献