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61.
To investigate the pathogenesis of hyperlipidemia-induced atherosclerosis, we examined age-dependent changes in platelet activity, blood coagulation and fibrinolysis in susceptibility to a high cholesterol diet (HCD) feeding in male ICR mice. Pretreatment of platelet-rich-plasma from HCD feeding mice for 3 days with epinephrine (300 microM) resulted in a marked enhancement of adenosine 5'-diphosphate (ADP: 0.1 microM) or collagen (0.7 microgram/ml)-stimulated aggregation compared with the same in control mice. Yohimbine as alpha 2-adrenergic blocker antagonized these aggregations in a dose-dependent manner. A significant increase in plasma total cholesterol and VLDL (very low-density lipoprotein)-LDL (low-density lipoprotein)-cholesterol and the liver/body weight ratio was observed in mice fed on HCD for 3 months (3-month HCD mice). In the early phase of this experiment, a significant increase in fibrinogen was observed. In the middle phase, increases in the activity of antithrombin III (ATIII) and alpha 2-plasmin inhibitor (alpha 2-Pl) followed. Plasminogen content gradually decreased in both normal diet and HCD mice throughout the experiment. The activity of plasminogen activator inhibitor (PAI) decreased in 3-month HCD mice. Morphological observation of the aortic arch from 3-month HCD mice revealed apparent atheromatous plaques not seen in control mice. These results suggest that 3-month HCD mice can be a convenient hyperlipidemia-induced atherosclerotic model and the changes in platelet activity, coagulation and fibrinolysis in the early phase may be a cause of pathologic changes in this model.  相似文献   
62.
Adélie penguins Pygoscelis adeliae in Enderby Land, Antarctica feed mainly on Euphausia superba during the chick rearing season in shelf areas where fast sea-ice remains: indicating that E. superba is abundant under the fast sea-ice in these areas. The shelf areas in Enderby Land, therefore, are unique since the previous studies of Adélie penguin diet in Ross Sea, Adélie Land and Prydz Bay show that E. crystallorophias is the most abundant krill species in shelf areas in general.  相似文献   
63.
64.
Glucose-6-phosphate dehydrogenase in a yeast, Hansenula mrakii IFO 0895 is induced when the cells are cultured in a medium containing lipid hydroperoxide. The enzyme was purified from H. mrakii to the homogeneous state on polyacrylamide gel electrophoresis. The molecular weight of the purified enzyme was estimated to be approximately 52kDa by SDS-PAGE and 130 kDa by Sephadex G-150column chromatography, respectively. The enzyme was specific to glucose-6-phosphate and NADP+, and Kmvalues for glucose-6-phosphate and NADP+ were 293µM and 24.1 µM, respectively. The enzyme activity was inhibited by diethylpyrocarbonate and 2, 4, 6-trinitrobenzene sulfonate, and by metal ions such as Zn2 +, Cd2 +, Cu2 +, and Al3 + . tert-Butyl hydroperoxide, a kind of lipid hydroperoxide, slightly(approximately 20%) increased the enzyme activity.  相似文献   
65.
An efficient asymmetric synthesis of the chiral N-(3-chloro-2-hydroxypropyl)anilines (2a and 2b) was achieved through the regioselective ring-opening reaction of chiral epichlorohydrin with aniline. This was applied to an asymmetric synthesis of the enantiomers of 1-[4,4-bis(4-fluorophenyl)butyl]-4-[2-hydroxy-3-(phenylamino)propyl]piperazine 1 as a novel potent dopamine uptake inhibitor. Both enantiomers as trihydrochlorides, 4a.3HCl and 4b.3HCl, could be synthesized in good total yields and optical purities of 100% ee in three steps synthesis, respectively. The absolute configurations of 4a.3HCl and 4b.3HCl were determined using the modified Mosher's method with the related compounds, the intermediates (2a and 2b) and the free bases (4a and 4b). The analytical results indicated that 4a.3HCl and 4b.3HCl have the (S)- and (R)-configuration, respectively, and a series of reactions to provide them proceeded without the apparent influence on the stereochemistry at the chiral centers. In in vitro pharmacological evaluations, 4a.3HCl and 4b.3HCl showed potent dopamine transporter binding affinities, high dopamine, moderate serotonin, and weak norepinephrine uptake inhibitory activities, and 4a.3HCl exhibited a more potent and selective dopamine uptake inhibition over the serotonin or norepinephrine uptake inhibition as compared with 4b.3HCl. An ex vivo evaluation revealed that the oral administrations of both enantiomers at a dose of 30 mg/kg in rats displayed apparent dopamine uptake inhibitory activities and 4a.3HCl had a stronger tendency to inhibit dopamine uptake compared with 4b.3HCl.  相似文献   
66.
Although leishmaniasis is regarded as a significant health problem in Ecuador by the Ministry of Health, and the incidence has increased over the last years, an official map on the geographic distribution of disease and sand fly vectors or a control strategy do not exist yet. This article reviews the current situation based on published information to improve our knowledge and understand the epidemiological situation of leishmaniasis in Ecuador in order to help future research and to develop a national control strategy. The disease is endemic in most provinces throughout Pacific coastal region, Amazonian lowlands, and some inter-Andean valleys with a total 21,805 cases reported during 1990-2003. Whereas cutaneous leishmaniasis (CL) is found throughout Ecuador, mucocutaneous leishmaniasis (MCL) appears to be restricted to the Amazon region; one, parasitologically unconfirmed case of visceral form was reported in 1949. Most human infections are caused by Leishmania (Viannia) spp., which is distributed in the subtropical and tropical lowlands; infections due to L. (Leishmania) spp. are found in the Andean highlands and in the Pacific lowlands as well. The proven vectors are Lutzomyia trapidoi and Lu. ayacuchensis. Canis familiaris, Sciurus vulgaris, Potos flavus, and Tamandua tetradactyla have been found infected with Leishmania spp. It is estimated that around 3000-4500 people may be infected every year, and that 3.1 to 4.5 millions people are estimated to be at risk of contracting leishmaniasis.  相似文献   
67.
Comparative study on the distribution of six species of bitterling in a creek in Fukuoka Prefecture was carried out. The upper part of the creek was fluvial, and the lower part stagnant.Acheilognathus lanceolatus, A. tabira subsp. (b) of Nakamura (1969),A. rhombeus andRhodeus atremius showed wide distribution in the creek throughout their life.A. limbatus seemed to be a fluvial species, andR. ocellatus smithii a lentic species. In the spawning season, however, all the species of bitterling, exceptingR. o. smithii, probably possess a common spawning ground in which mussels occur at a relatively high density. Adult females ofA. lanceolatus, A. tabira subsp. (b) andR. atremius without ripe eggs aggregated in the lower, stagnant parts of the creek. Most juveniles of these species and ofA. rhombeus seemed to grow in the lower part of the creek, and then migrate upward untill their spawning season. No species among the same phylogenetic group has the same set of the life modes (spawning season, spawning sites, aggregation of females without ripe eggs in the lower part of the creek and probability of upstream migration of 0-year-old fish toward spawning sites).  相似文献   
68.
Pollen is a clinically important airborne allergen and one of the major causes of allergic conjunctivitis. A subpopulation of patients with atopic dermatitis (AD) are also known to have exacerbated skin eruptions on the face, especially around the eyelids, after contact with pollen. This pollen-induced skin reaction is now known as pollen dermatitis. Macrophage migration inhibitory factor (MIF) is a pluripotent cytokine that plays an essential role in allergic inflammation. Recent findings suggest that MIF is involved in several allergic disorders, including AD. In this study, MIF knockout (KO), MIF transgenic (Tg) and WT littermate mice were immunized with ragweed (RW) pollen or Japanese cedar (JC) pollen and challenged via eye drops. We observed that the numbers of conjunctiva- and eyelid-infiltrating eosinophils were significantly increased in RW and JC pollen-sensitized MIF Tg compared with WT mice or MIF KO mice. The mRNA expression levels of eotaxin, interleukin (IL)-5 and IL-13 were increased in pollen-sensitized eyelid skin sites of MIF Tg mice. An in vitro analysis revealed that high eotaxin expression was induced in dermal fibroblasts by MIF combined with stimulation of IL-4 or IL-13. This eotaxin expression was inhibited by the treatment with CD74 siRNA in fibroblasts. These findings indicate that MIF can induce eosinophil accumulation in the conjunctiva and eyelid dermis exposed to pollen. Therefore, targeted inhibition of MIF might result as a new option to control pollen-induced allergic conjunctivitis and pollen dermatitis.  相似文献   
69.
The binding site for calcitonin gene-related peptide (CGRP) was solubilized with 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate (CHAPS) in an active form from porcine spinal cord. 125I-labeled human alpha-CGRP (125I-CGRP) binding to the solubilized protein was determined by filtration using a GF/B glass filter. The maximal binding activity (approximately 60% of the crude membrane fraction) was obtained with 5 mM CHAPS. 125I-CGRP binding to the solubilized protein was of high affinity, saturability, and high specificity, having KD and Bmax values of 3.69 pM and 338 fmol/mg of protein, respectively. The binding activity was eluted in a single peak with a molecular mass of 400,000 daltons by gel filtration on TSK gel G4000SW. These results suggest that the solubilized protein may be responsible for the specific binding site.  相似文献   
70.
Two new lindenane sesquiterpene dimers, spicachlorantins A and B (1 and 2), were isolated from the roots of Chloranthus spicatus along with a known related compound, chloramultilide A (3). Their structures and the absolute stereostructures were established by 1D and 2D NMR as well as by CD spectroscopic analyses.  相似文献   
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