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991.
The novel antitumor compound NC-190 strongly inhibited the growth of FM3A cells with an IC50 of 0.019 microg/ml (0.042 microM) when cultured with NC-190 for 48 h. NC-190 potently suppressed DNA synthesis, with 90% inhibition observed at 0.1 microg/ml of NC-190. RNA and protein syntheses were also suppressed under the same conditions, but to a lesser extent. We then measured the cellular enzymatic activities of DNA polymerase alpha, RNA polymerase, thymidine kinase, thymidylate synthase and Leu-tRNA synthetase of FM3A cells cultured with or without NC-190. Of these 5 enzymes, the activity of thymidine kinase was most strongly suppressed by NC-190, by 77%. Although NC-190 did not directly inhibit the activitiy of thymidine kinase in a cell-free system, expression of mRNA of thymidine kinase was suppressed by 75% in NC-190-treated cells. These results indicate that NC-190 can suppress the expression of the gene for thymidine kinase and the inhibition of thymidine kinase contributes to the inhibition of cell growth by NC-190 together with the inhibition of topoisomerase II.  相似文献   
992.
The rate of propagation of influenza virus in human adenocarcinoma Caco-2 cells was found to negatively correlate with the concentration of fetal bovine serum (FBS) in the culture medium. Virus replicated more rapidly at lower FBS concentrations (0 or 2%) than at higher concentrations (10 or 20%) during an early stage of infection. Basal and interferon (IFN)-induced levels of typical IFN-inducible anti-viral proteins, such as 2',5'-oligoadenylate synthetase, dsRNA-activated protein kinase and MxA, were unaffected by variation in FBS concentrations. But promyelocytic leukemia protein (PML) was expressed in a serum-dependent manner. In particular, the 65 to 70 kDa isoform of PML was markedly upregulated following the addition of serum. In contrast, other isoforms were induced by IFN treatment, and weakly induced by FBS concentrations. Immunofluorescence microscopy indicated that PML was mainly formed nuclear bodies in Caco-2 cells at various FBS concentrations, and the levels of the PML-nuclear bodies were upregulated by FBS. Overexpression of PML isoform consisting of 560 or 633 amino acid residues by transfection of expression plasmid results in significantly delayed viral replication rate in Caco-2 cells. On the other hand, downregulation of PML expression by RNAi enhanced viral replication. These results indicate that PML isoforms which are expressed in a serum-dependent manner suppress the propagation of influenza virus at an early stage of infection.  相似文献   
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994.
A 17 year old male suffered recurrent subarachnoid hemorrhages due to multiple aneurysms in the distal branches of the cerebral arteries. Autopsy revealed arteriopathy as well as the aneurysms. The arteriopathy was widespread, affecting the distal branches of small and medium-sized muscular cerebral arteries, as well as the anterior and posterior spinal arteries, and vasocorona. The arteriopathy was characterized by prominent intimal thickening, discontinuity or absence of the internal elastic lamina, and thinning and/or disappearance of smooth muscle in the tunica media with fibroplasia. Slight intimal thickening was also observed in the arteries of the circle of Willis and its major branches, as well as in the basilar artery. However, the arterioles, venules and veins showed no remarkable features. The arterial lesions were found only in the central nervous system. The multiple aneurysms in the distal branches of the cerebral arteries, which had produced the main symptoms and clinical signs, were due to the arteriopathy.  相似文献   
995.
Calorigenic actions of noradrenaline and glucagon on isolated epididymal fat cells from warmacclimated controls, cold-acclimated and heatacclimated rats were measured by the use of a twin-type conduction microcalorimeter. Both noradrenaline and glucagon stimulated heat production in isolated adipocytes maximally in doses of 1 g/ml and 10g/ml, respectively. Maximal responsiveness of adipocytes per unit cell to noradrenaline was not influenced by cold acclimation, while it was reduced by heat acclimation. Maximal response in total epididymal fat cells to noradrenaline was increased in cold acclimation and not changed in heat acclimation at increased numbers of adipocytes in both cold-acclimated and heatacclimated animals. Maximal response per unit cell as well as per total epididymal fat cells to glucagon was increased in cold acclimation and reduced in heat acclimation.The present results indicate that the modified responses of target adipocytes to noradrenaline and glucagon are involved in the development of temperature acclimation.  相似文献   
996.
Influenza-associated acute encephalopathy in Japanese children in 1994-2002   总被引:6,自引:0,他引:6  
We addressed the incidence of influenza-associated acute encephalopathy, which is distinct from Reye syndrome, in children in Japan. Eighty-nine children with a mean age of 3.8 years were reported to have developed this disease during eight influenza seasons (December 1994-April 2002) in Hokkaido, Japan. None of them had received aspirin. Most of the patients rapidly became comatose with or without convulsions with a mean interval of 1.7 days from the onset of fever to the onset of central nervous system symptoms. Thirty-three (37.1%) patients died and 17 (19.1%) patients had neurological sequelae. A total of 53 (59.6%) cases were proved to have an influenza virus infection. Interleukin-6 and tumor necrosis factor-alpha were markedly elevated in serum and cerebrospinal fluid samples from two patients who died after a rapid, fulminant course. A post-mortem examination of one fatal case revealed vasogenic brain edema with generalized vasculopathy, suggesting that the generalized impairment of vascular endothelial cells caused by highly activated cytokines plays a central role in the pathophysiology of this disease. We conclude that influenza-associated acute encephalopathy may be an underestimated syndrome and is another reason to promote vaccination against influenza in infants and younger children.  相似文献   
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Background: Only a few studies have evaluated the abnormalities of ambulatory blood pressure (ABP) in patients with nephrotic syndrome (NS). Methods: The 24-h ABPs were measured in primary NS patients with acute onset of disease and analyzed in relation to the clinical variables. Results: Our subjects comprised 21 patients: 17 with minimal change disease and 4 with focal segmental glomerulosclerosis. Of these patients, 8 (38%) had daytime hypertension, 13 (62%) had nighttime hypertension, and 13 (62%) were non-dippers (nighttime-to-daytime ratio of ABP: NDR > 0.9). The serum sodium level was correlated with the average 24-h ABP and NDR, after adjustment for other clinical variables, such as the increase in body weight, serum albumin level, and urinary protein excretion. The data from repeated ABP measurements, before and after the achievement of remission, showed a marked decrease in the average 24-h ABP after remission. Furthermore, change in the serum sodium level was significantly correlated with the change in NDR. Conclusion: These results suggest that alteration in renal handling of sodium and water, which might be reflected in serum sodium level, is involved in the abnormality of circadian blood pressure in primary NS patients.  相似文献   
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