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71.
ABSTRACT

Environmental risk is a measure of potential threats to the environment and combines the probability that events will cause or lead to degradation of the environment and the severity of that degradation. Evaluation of environmental risk factors requires linguistic terms to be used rather than exact numerical assignments. The fuzzy set theory provides a useful tool for converting linguistic terms into numerical evaluations. In this article, we will try to select the best location for the Faculty of Management of the Istanbul Technical University taking care of the predetermined environmental criteria by using fuzzy TOPSIS. The decision matrix is composed of linguistic evaluations for the alternatives with respect to the environmental risk criteria. The Macka Campus area has been selected after the multicriteria evaluation. A sensitivity analysis is also realized to see if the minor changes in criteria weights cause any change in the ranking of alternatives. Unless the importance of the criteria rock or soil structure, remoteness to health facilities, transportation availability, and transportation costs is changed to be from low to extremely low importance, the Macka Campus is still the selected alternative.  相似文献   
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73.
Newly synthesized basolateral markers can traverse recycling endosomes en route to the surface of Madin-Darby canine kidney cells; however, the routes used by apical proteins are less clear. Here, we functionally inactivated subsets of endocytic compartments and examined the effect on surface delivery of the basolateral marker vesicular stomatitis virus glycoprotein (VSV-G), the raft-associated apical marker influenza hemagglutinin (HA), and the non-raft-associated protein endolyn. Inactivation of transferrin-positive endosomes after internalization of horseradish peroxidase (HRP)-containing conjugates inhibited VSV-G delivery, but did not disrupt apical delivery. In contrast, inhibition of protein export from apical recycling endosomes upon expression of dominant-negative constructs of myosin Vb or Sec15 selectively perturbed apical delivery of endolyn. Ablation of apical endocytic components accessible to HRP-conjugated wheat germ agglutinin (WGA) disrupted delivery of HA but not endolyn. However, delivery of glycosylphosphatidylinositol-anchored endolyn was inhibited by >50% under these conditions, suggesting that the biosynthetic itinerary of a protein is dependent on its targeting mechanism. Our studies demonstrate that apical and basolateral proteins traverse distinct endocytic intermediates en route to the cell surface, and that multiple routes exist for delivery of newly synthesized apical proteins.  相似文献   
74.
It is well accepted that aging and HIV infection are associated with quantitative and functional changes of CMV-specific T cell responses. We studied here the expression of Mip-1β and the T cell maturation marker CD27 within CMVpp65-specific CD4+ and CD8+ T cells in relation to age, HIV and active Tuberculosis (TB) co-infection in a cohort of Tanzanian volunteers (≤16 years of age, n = 108 and ≥18 years, n = 79). Independent of HIV co-infection, IFNγ+ CMVpp65-specific CD4+ T cell frequencies increased with age. In adults, HIV co-infection further increased the frequencies of these cells. A high capacity for Mip-1β production together with a CD27low phenotype was characteristic for these cells in children and adults. Interestingly, in addition to HIV co-infection active TB disease was linked to further down regulation of CD27 and increased capacity of Mip-1β production in CMVpp65-specific CD4+ T cells. These phenotypic and functional changes of CMVpp65-specific CD4 T cells observed during HIV infection and active TB could be associated with increased CMV reactivation rates.  相似文献   
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Some fused heterocyclic compounds as eukaryotic topoisomerase II inhibitors   总被引:2,自引:0,他引:2  
Our previously synthesized 37 compounds, which are 2,5,6-substituted benzoxazole, benzimidazole, benzothiazole, and oxazolo(4,5-b)pyridine derivatives, were tested for their eukaryotic DNA topoisomerase II inhibitory activity in cell free system and 28 were found to inhibit the topoisomerase II at an initial concentration of 100 microg/ml. After further testing at a lower range of concentrations, 12 derivatives, which were considered as positive topoisomerase inhibitors, exhibited IC50 values between 11.4 and 46.8 microM. Etoposide was used as the standard reference drug to compare the inhibitor activity. Among these compounds, 2-phenoxymethylbenzothiazole (3f), 6-nitro-2-(2-methoxyphenyl)benzoxazole (1a), 5-methylcarboxylate-2-phenylthiomethylbenzimidazole (3c), and 6-methyl-2-(2-nitrophenyl)benzoxazole (1c) were found to be more active than the reference drug etoposide. Present results point out that, besides the very well-known bi- and ter-benzimidazoles, compounds with single bicycle fused ring systems in their structure such as benzimidazole, benzoxazole, benzothiazole, and/or oxazolopyridine derivatives also exhibit significant topoisomerase II inhibitory activity.  相似文献   
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78.
Nitric oxide (NO) is known to be produced by macrophages, endothelial cells and neurons and synthesized by an enzyme called nitric oxide synthase (NOS). Various effector mechanisms and infections can affect the NO production. Excessive amount of NO will lead to biochemical reactions, which cause toxic effects. In this study the role of NO has been evaluated in larval toxocarosis, which is a systemic parasite infection caused by T. canis larvae. Infection was established in the Balb/c mice with or without inducible NOS (iNOS) inhibition and the effects of infection and NOS inhibition were observed according to the results of SOD and LPx measurements in brain tissue and NADPH-diaphorase (NADP-d) histochemistry. Results of NADPH-d histochemistry indicate that iNOS inhibition has protective effect on the brains of infected mice and that larval T. canis infection could be related to oxidative stress, and NO production and iNOS inhibition can protect the tissue from damage in this infection.  相似文献   
79.
Baseline biological growth data were obtained under laboratory conditions for four local populations of the phlebotomine sand fly R papatasi (Scopoli, 1786) (Diptera: Psychodidae) in different eco-regions at altitudes between 368 and 1117 m in the Sanliurfa province of Turkey. The developmental time from egg to adult was found to be significantly different among the populations: 36 days for the AKL population (368 m), 43 days for the HHR population (488 m), 45 days for the HMD population (644 m), and 49 days for the ALT population (1117 m), respectively. Based on cohorts of adults in each population, horizontal life tables were constructed. The average longevity was determined to be in the range of 8.75 +/- 2.39 to 11.60 +/- 3.48 days for adult females, and it was found to be slightly longer for adult males. No significant difference was found in life expectancy at emergence, e(x) when x=1, between females and males in general (P>0.05) in all the populations. While significant differences could be demonstrated among populations for predictive parameters such as net reproductive rate, Ro, and generation time, Tc, no significant differences among the populations were found in terms of intrinsic rate of increase, r(m), finite rate of increase, lambda, birth (b) and death (d) rates (P>0.05). Populations that produced offspring earlier in life also produced more total female offspring, since Tc was negatively correlated with Ro among the populations (r = -0.686, 0.01相似文献   
80.
Endothelin (ET)-1 is implicated in the pathophysiology of cardiovascular diseases although its role in obesity anomalies has not been fully elucidated. This study was designed to examine the impact of ET-1 receptor A (ETA) ablation on obesity-induced changes in cardiac geometry and contractile function, as well as the mechanisms involved with a focus on autophagy. Cardiomyocyte-specific ETA receptor knockout (ETAKO) and WT mice were fed either low-fat (10% calorie from fat) or high-fat (45% calorie from fat) diet for 24?weeks. Glucose tolerance test was examined to confirm insulin resistance. High-fat diet intake compromised myocardial geometry (enlarged left ventricular diameters in systole and diastole), morphology (cardiac hypertrophy, increased wall thickness and interstitial fibrosis), contractile function (reduced fractional shortening, ejection fraction and cardiomyocyte shortening) and intracellular Ca2+ handling, the effect of which was significantly attenuated by ETAKO. TUNEL staining revealed overt apoptosis in high-fat-fed group, the effect was reverted by ETAKO. Western blot analysis noted that high-fat intake downregulated leptin receptor and PPARγ, insulin signaling (elevated basal/dampened insulin-stimulated phosphorylation of Akt and IRS1), phosphorylation of AMPK, ACC, upregulated GATA-4, ANP, NFATc3, PPARα, m-TOR/p70s6k signaling, which were attenuated by ETAKO with the exception of AMPK/ACC. Furthermore, high-fat intake suppressed cardiac autophagy, which was abrogated by ETAKO. In cultured murine cardiomyocytes, palmitic acid challenged mimicked high-fat diet-induced hypertrophic and autophagic responses, the effect of which were abolished by the ETA receptor antagonist BQ123 or mTOR inhibitor rapamycin. These results suggest that inhibition of ETA rescues high-fat intake-induced cardiac anomalies possibly through autophagy regulation.  相似文献   
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