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991.
Kajimura N Nishikawa M Uchiyama M Kato M Watanabe T Nakajima T Hori T Nakabayashi T Sekimoto M Ogawa K Takano H Imabayashi E Hiroki M Onishi T Uema T Takayama Y Matsuda H Okawa M Takahashi K 《The American journal of psychiatry》2004,161(4):748-751
OBJECTIVE: The authors' goal was to identify differences in regional brain activity between physiological and benzodiazepine-induced sleep to clarify the brain structures involved in the drug's hypnotic effect. METHOD: Using positron emission tomography, they compared regional cerebral blood flow during non-REM sleep in nine volunteers treated with placebo or triazolam, a short-acting benzodiazepine, in a double-blind, crossover design. RESULTS: Blood flow in the basal forebrain and amygdaloid complexes was lower during non-REM sleep when subjects were given triazolam than when they were given placebo. CONCLUSIONS: The hypnotic effect of the benzodiazepines may be mediated mainly by deactivation of the forebrain control system for wakefulness and also by the anxiolytic effect induced by deactivation of the emotional center. 相似文献
992.
Expression of dopamine receptors (DA-Rs) in astrocytes was examined in vitro and in vivo using primary cultured astrocytes and brain slices from rat basal ganglia. Astrocytes from basal ganglia expressed DA D1-, D3-, D4- and D5-receptors and D4-mediated signal transduction in response to DA, suggesting possible involvement of astrocytes in the pharmacological action of atypical antipsychotic drugs and in DA response in some neurological diseases. 相似文献
993.
Little attention has been given to the effects of delirium on the course of depression. In clinical practice, we sometimes observe delirium brought on incidentally by severe physical illness or therapeutic drugs such as tricyclic antidepressants. Recently, investigators have discussed whether delirium can in fact have a beneficial effect on the course of depression. We present three cases of delusional depression in which depressive symptoms resolved after patients recovered from incidental delirium caused in two cases by medication, and by respiratory distress leading to asphyxiation in the third. We surmise that delirium may create a biological effect similar to that of electroconvulsive therapy (ECT), which is widely hailed as an effective treatment for delusional depression. Retrograde amnesia caused by delirium and the supportive milieu during treatment of the delirium may have a beneficial psychological effect on recovery from delusional depression. 相似文献
994.
Ogawa T Takiyama Y Sakoe K Mori K Namekawa M Shimazaki H Nakano I Nishizawa M 《Neurology》2004,62(1):107-109
The authors describe two patients in a Japanese family with autosomal recessive spastic ataxia of Charlevoix-Saguenay. They presented early onset spastic ataxia, sensorimotor neuropathy, nystagmus, slurred speech, and hypermyelinated retinal nerve fibers. The authors identified a homozygous missense mutation (T7492C) in the SACS gene, which resulted in the substitution of arginine for tryptophan at amino acid residue 2498 (W2498R). 相似文献
995.
Expression Levels of Renal Organic Anion Transporters (OATs) and Their Correlation with Anionic Drug Excretion in Patients with Renal Diseases 总被引:3,自引:0,他引:3
Sakurai Y Motohashi H Ueo H Masuda S Saito H Okuda M Mori N Matsuura M Doi T Fukatsu A Ogawa O Inui K 《Pharmaceutical research》2004,21(1):61-67
PURPOSE: Because the urinary excretion of drugs is often decreased in renal diseases, dosage regimens are adjusted to avoid adverse drug reactions. The aim of present study was to clarify the alteration in the levels of renal drug transporters and their correlation with the urinary drug excretion in renal diseases patients. METHODS: We quantified the mRNA levels of human organic anion transporters (hOATs) by real-time polymerase chain reaction and examined the excretion of the anionic drug, cefazolin, in renal disease patients. Moreover, transport of cefazolin by hOAT1 and hOAT3 were examined using HEK293 transfectants. RESULTS: Among four hOATs, the level of hOAT1 mRNA was significantly lower in the kidney of patients with renal diseases than in the normal controls. The elimination constant of cefazolin showed a significant correlation with the values of phenolsulfonphthalein test and mRNA levels of hOAT3. The uptake study using HEK293 transfectants revealed that cefazolin and phenolsulfonphthalein were transported by hOAT3. CONCLUSIONS: These results suggest that hOAT3 plays an important role for anionic drug secretion in patients with renal diseases and that the expression levels of drug transporters may be related to the alteration of renal drug secretion. 相似文献
996.
Hoshino K Ogawa K Hishitani T Isobe T Eto Y 《Journal of the American College of Nutrition》2004,23(5):497S-500S
BACKGROUND: Intravenous administration of magnesium sulphate (MgSO(4)) is a very effective and safe treatment for torsades de pointes (TdP) associated with acquired long QT syndrome (LQTS) in adults. Discussed here is the efficacy of MgSO(4) for TdP in children with congenital and acquired LQTS. METHODS: The optimal MgSO(4) dosage and serum magnesium (SMg) was determined in six consecutive children with TdP; four had congenital LQTS and two had acquired LQTS. A bolus injection of MgSO(4) was given intravenously over 1 to 2 minutes followed by continuous infusion for the next 2 to 7 days. RESULTS: Of the six patients, five responded completely to the initial bolus of 6.1 +/- 4.2 mg/kg (range, 2.3-12 mg/kg). One (a neonate with congenital LQTS) required a total of 30 mg/kg until complete TdP elimination. Continuous infusion was given at rates of 0.3 to 1.0 mg/kg/hr with no recurrence of TdP. SMg concentration was 3.9 +/- 1.0 mg/dL (2.9-5.4 mg/dL) immediately after bolus injection. CONCLUSION: Intravenous MgSO(4) infusion effectively treated TdP in children with LQTS. Optimal bolus dosage, infusion rates and SMg concentration were 3 to 12 mg/kg, 0.5 to 1.0 mg/kg/hr and 3 to 5 mg/dL, respectively. 相似文献
997.
998.
Arsenic trioxide (As2O3) induces clinical remission in acute promyelocytic leukemic patients and apoptosis in various tumor cells in vitro. To develop As2O3-based combination chemotherapy for renal cell carcinoma (RCC), we investigated the cytotoxic effects of As2O3 in combination with chemotherapeutic agents or L-buthionine sulfoximine (BSO), a glutathione (GSH) synthesis inhibitor. Cytotoxicity and synergy were assessed by the MTT assay and isobolographic analysis, respectively. Apoptosis was monitored by Hoechst 33342 staining, flow cytometrical analysis, and DNA fragmentation assay. Treatment of ACHN cells with As2O3 in combination with adriamycin, vinblastine, or 5-fluorouracil induced an antagonistic effect. However, combination treatment with As2O3 and BSO resulted in a synergistic cytotoxic effect. Synergy was also obtained in Caki-1, Caki-2, NC65 cells and freshly derived RCC cells from 6 patients. Simultaneous treatment of ACHN cells with As2O3 and BSO caused significantly more cytotoxicity than the As2O3 first BSO second or the reverse treatment. We further explored the mechanisms underlying this synergistic effect and found that the synergistic cytotoxicity of As2O3 and BSO was realized by inducing apoptosis. This combination markedly decreased intracellular GSH content and GSH-S-transferase (GST) activity. However, neither the intracellular GSH nor GST was decreased by As2O3 with adriamycin, vinblastine, or 5-fluorouracil. Furthermore, the GSH-increasing agents N-acetylcysteine and lipoic acid significantly inhibited the combined cytotoxicity of As2O3 and BSO. These findings indicate that BSO sensitizes RCC cells to As2O3-induced apoptosis through the down-regulation of the intracellular GSH redox system, suggesting the potential application of a combination of As2O3 and BSO for the treatment of RCC. 相似文献
999.
Kurebayashi J Nishimura R Tanaka K Kohno N Kurosumi M Moriya T Ogawa Y Taguchi T 《Breast cancer (Tokyo, Japan)》2004,11(4):389-395
OBJECTIVE: The significance of serum tumor markers in monitoring advanced breast cancer patients is still controversial. To clarify this issue, the Tumor Marker Study Group of the Japanese Breast Cancer Society conducted a prospective study. METHODS: Patients with advanced breast cancer who were treated with systemic therapy between January and December 2002 were recruited from five collaborative institutes in Japan. The patients were monitored every four weeks using three serum tumor markers, CEA, CA 15-3 and NCC-ST-439 during the therapy. RESULTS: Findings from 108 eligible patients were analyzed. The pretreatment positivity rates were 51.9% for CEA, 50% for CA 15-3, and 34.3% for NCC-ST-439. The changes in each marker level at 8 and 12 weeks but not at 4 weeks after the start of therapy seemed to correlate with the response to therapy in pretreatment marker-positive patients but not in negative patients. The Cox proportional hazard model revealed a greater than 20% reduction in CEA, CA 15-3 or NCC-ST-439 levels at 4, 8 and/or 12 weeks after the start of therapy to be an independent predictive factor for longer time-to-progression (TTP) in pretreatment marker-positive patients. CONCLUSION: This prospective study supported the findings obtained from our previous retrospective study that in pretreatment marker-positive patients 1) the changes in serum tumor marker levels after the start of therapy correlate with the response to therapy; and 2) a greater than 20% reduction in the tumor marker levels was a favorable predictive factor for TTP during systemic therapy. When the pretreatment serum level of these markers is over the respective cut-off value, sequential measurement of them may be useful for evaluating the efficacy of treatment as well as monitoring the outcome of patients with advanced breast cancer. 相似文献
1000.
Conjugated docosahexaenoic acid suppresses KPL-1 human breast cancer cell growth in vitro and in vivo: potential mechanisms of action 总被引:3,自引:0,他引:3 下载免费PDF全文
Tsujita-Kyutoku M Yuri T Danbara N Senzaki H Kiyozuka Y Uehara N Takada H Hada T Miyazawa T Ogawa Y Tsubura A 《Breast cancer research : BCR》2004,6(4):R291-R299