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Phosphatidylinositol (PI) signaling during organophosphate (OP) induced convulsions and tissue Ca2+ changes in 10 weeks old male, and 14 weeks old non-pregnant and pregnant female rats, and the offspring of the latter were explored. Brain inositol and inositol-1-phosphate (Ins1P) served as indices of alterations in brain PI signaling, and brain tissue Ca2+ as an index of early neuronal injury. A dose of malaoxon OP, which produced convulsions in about 60% of the exposed rats in different rat groups, was 39.2 for male, and 8.2 mg/kg for pregnant female rats, respectively. Malaoxon (8.2 mg/kg) did not produce convulsions in non-pregnant female rats. All the rats were followed for 1 or 4 hr subsequent to malaoxon. Malaoxon decreased cerebral inositol in both male and female rats, and the decrease was similar in spite of the dose difference. The decrease was larger in the convulsing than in the non-convulsing rats. A tendency towards a decrease of brain inositol also occurred in the offspring. Ins1P levels were markedly increased in male, and also in non-pregnant female rats, but not in the brains of pregnant female rats. Ins1P was not markedly changed in the brains of the offspring. Malaoxon elevated brain tissue Ca2+ in male but not in female rats or their offspring. Cholinergic systems and PI signaling in the brain seem to be associated with OP-induced convulsions both in male and female rats; females seem to be more sensitive than males. Malaoxon may also have slightly modified PI signaling in the offspring brain. Hormonal factors are likely to modify OP CNS toxicity and cholinergic stimulation of brain PI signaling. 相似文献
3.
J Uusi-Simola T Serén T Sepp?l? A Kosunen I Auterinen S Savolainen 《Applied radiation and isotopes》2004,61(5):845-848
Tissue equivalent proportional counter microdosimetry has been applied in the dosimetry of epithermal neutron beams as they can provide an independent and accurate method to determine gamma ray and neutron absorbed doses. Dosimetric comparison has been performed using a tissue equivalent proportional counter, dual ionisation chambers and DORT computer code at FiR 1 boron neutron capture therapy facility in Espoo, Finland. The three methods were applied to determine neutron and gamma ray absorbed doses at 25, 40, 60 and 120 mm depths along the beam centerline in a water-filled PMMA phantom. The determined absorbed doses were found to agree within the limits of the estimated uncertainties. 相似文献
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Male Wistar rats exposed to 5, 10 or 20 p.p.m. 4-methylcyclohexyl-1,6-dicarboxylic acid anhydride vapour for 2-11 weeks showed dose-dependent blood anhydride concentrations. The maximum concentrations were found after two weeks. At five exposure weeks, they were smaller but they did not decrease further thereafter. The change was coincident with increased epoxide hydrase activity in liver. The excretion of 4-methylcyclohexyl-1,6-dicarboxylic acid was detected in the urine. The excretion was linearly related to the exposure in specimens collected during the 10th and 11th week. Brain acetylcholinesterase activity was transiently inhibited by the exposure at the two higher doses while decreased enzyme activity in the isolated spinal cord axons was only found after 11 weeks. This change was simultaneous with increased creatine kinase activity in the cerebellar homogenate. In the occupational setting, acetylcholinesterase activity might only be significantly inhibited in lungs because of the low exposure levels. 相似文献
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Kaisa M. Heiskanen Silvia Münzing Fritz Krombach Kai M. Savolainen 《Archives of toxicology》1997,71(10):627-632
The effects of linoleic acid, linoleic acid anilide, and arachidonic acid on the expression of CD11b/CD18, CD11c/CD18 integrins
and l-selectin on human neutrophils were studied by flow cytometry in a whole blood assay. None of these compounds had any effect
on the basal expression of CD11b, CD11c, or l-selectin in the concentration range of 20–100 μM. However, linoleic acid at a concentration of 1000 μM slightly up-regulated
CD11b and CD11c by a factor of 2.1 and 1.7, respectively. Linoleic acid, linoleic acid anilide, and arachidonic acid did not
affect the formyl-methionyl-leucyl-phenylalanine induced up-regulation of CD11b or CD11c. However, linoleic acid and linoleic
acid anilide slightly inhibited the phorbol myristate acetate (PMA)-induced expression of CD11b, which was decreased by 27
and 21% at concentrations of 100 and 1000 μM, respectively. Likewise, arachidonic acid at 40 μM inhibited the PMA-induced
expression of CD11b by 19%. Our results suggest that linoleic acid, linoleic acid anilide, and arachidonic acid do not dramatically
affect the expression of leukocyte adhesion molecules in a whole blood assay.
Received: 17 February 1997 / Accepted: 5 May 1997 相似文献
8.
Mary ER O'Brien Janet Hardy Sylvia Tan Jackie Walling Brian Peters Sarah Hatty Eve Wiltshaw 《Cancer chemotherapy and pharmacology》1992,30(3):245-248
Summary A total of 16 patients with recurrent epithelial ovarian cancer were treated with sulofenur (LY 186641), a novel oral sulfonylurea. All subjects had received previous chemotherapy. Anaemia occurred in all 16 patients, 14 of whom required a blood transfusion, and 2/16 patients received methylene blue for breathlessness due to methaemaglobinaemia. Treatment was discontinued in 2/16 cases due to rising liver enzyme values, which reverted to normal on cessation of the drug. There was no nausea or alopecia. Only two minor responses were seen. Plasma drug levels were insufficient to result in antitumour activity as extrapolated from animal data. Further studies that attempt to increase the bioavailability and improve the therapeutic index are warranted. 相似文献
9.
Phylogenetic analysis of rhinovirus isolates collected during successive epidemic seasons 总被引:4,自引:0,他引:4
Human rhinoviruses (HRV) have been shown to be the major causative agent for mild respiratory infections, but also associated with more serious diseases, such as acute otitis media and pneumonia in children, and asthma. Despite the economical and medical importance of HRV, little is known about the circulation and genetic diversity of HRV during a given season. The aim of this study was to genetically characterize HRV strains causing acute respiratory infections in a cohort of small children during a 2 years follow-up time. Genetic relationships between 61 HRV field isolates were studied using partial genomic sequencing in the VP4/VP2 region (420 nt) and phylogenetic analysis of these sequences. Sequences from the clinical isolates clustered in the two previously known phylogenetic clades, the designated genetic group 2 (including HRV 14) being more predominant. The maximum genetic variation within group 1 was 32.3% and within group 2 it was 32.7%. Several distinct clusters could be observed, some of which were strictly seasonal, whereas some other variants were detected during several seasons. The results of this study show striking genetic diversity of the HRV strains circulating in a given community during a short time. 相似文献
10.
Antti V. Savolainen 《Macromolecular chemistry and physics.》1973,172(1):213-220
Dynamic differential calorimetry measurements of poly(oxy-2,6-dimethyl-1,4-phenylene) and poly(oxy-2,6-dimethoxy-1,4-phenylene) at the glass transition range show that both the location and the shape of the curves are dependent upon the thermal history of the samples. The shape of the curves can be explained by means of the hole theory. The increase of length of side chain groups causes the glass transition to move to lower temperature which is attributed to the flexibility of the side chain substituents as well as to the decreased intermolecular effects. The apparent activation energies of the glass transition in poly(oxy-2,6-dimethyl-1,4-phenylene) and poly(oxy-2,6-dimethoxy-1,4-phenylene) follow the WILLIAMS -LANDEL -FERRY equation approaching the empirical curve for sterically restricted bulkly polymers devised by LEWIS . 相似文献