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1.
A series of new 4-(3-(4-substitutedphenyl)-3a,4-dihydro-3H-indeno[1,2-c]pyrazol-2-yl) benzenesulfonamides (712) was synthesized starting from 2-(4-substitutedbenzylidene)-2,3-dihydro-1H-inden-1-one (16) and 4-hydrazinobenzenesulfonamide. The substituted benzaldehydes from which the key intermediate was prepared by introducing 2- or 4-substituents such as fluorine, hydroxy, methoxy, or the 3,4,5-trimethoxy moieties. The compounds were tested for their cytotoxicity, tumor-specificity and potential as carbonic anhydrase (CA, EC 4.2.1.1) inhibitors. The 3,4,5-trimethoxy and the 4-hydroxy derivatives showed interesting cytotoxic activities, which may be crucial for further anti-tumor activity studies, whereas some of these sulfonamides strongly inhibited both human (h) cytosolic isoforms hCA I and II.  相似文献   
2.
Background:The effect of proteasome inhibitors on atherosclerosis is known to vary depending on the atherosclerosis stage. Previous studies have shown that the highest proteasome expression in atherosclerotic lesions is at the progression stage. Adhesion molecules play a role in the progression stage of atherosclerosis, but no studies have analyzed the effect of proteasome inhibitors on the expression of adhesion molecules at this stage.Methods:This experimental study aimed to analyze the effect of a proteasome inhibitor, namely bortezomib, on the vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule1 (ICAM-1) expressions in blood vessels of rat model of atherosclerosis at the progression stage. This study used 18 male Wistar rats divided into three groups, i.e. group I that is the control group given standard feed, group II induced by atherosclerosis, and group III induced by atherosclerosis and given bortezomib. Atherosclerosis induction was performed using vitamin D3 (700,000 IU/kg) orally by gastric intubation on the 1st day and atherogenic feed given for four days. Bortezomib 50 µg/kgBW/day was administered intra-peritoneally. The expression of VCAM-1 and ICAM-1 molecules was measured using immunohistochemistry and analyzed quantitatively using Adobe Photoshop software.Results:The statistical test showed differences in VCAM-1 expression between atherosclerosis + Bortezomib group and atherosclerosis group, but there were no differences in the expression of ICAM-1 and atherosclerotic lesions between the groups.Conclusion:Administration of bortezomib 50μg/kg for four days in progressive atherosclerosis model rats can inhibit VCAM-1 expression, although it does not affect ICAM-1 expression and cannot inhibit atherosclerotic lesion formation.Key Words: Atherosclerosis, Bortezomib, Proteasome, VCAM-1, ICAM-1  相似文献   
3.
The in vitro effects of melatonin (N-acetyl-5-methoxy-tryptamine) on human carbonic anhydrase isozymes (HCA-I and HCA-II) from human erythrocytes and in vivo effects on rat erythrocytes carbonic anhydrase (CA) were determined. Human erythrocyte carbonic anhydrase isozymes were purified by haemolysate preparation and Sepharose-4B-L tyrosine-sulfanilamide affinity gel chromatography. The HCA-I enzyme, having a specific activity of 7337.5 EU/mg protein, was purified 843-fold with a yield of 60% and the HCA-II enzyme, having a specific activity of 17067EU/mg protein, was purified 1962-fold with a yield of 22.7%. For in vitro experiments, the enzyme activity was minimal at 2 x 10(-4) M melatonin concentration and increased above this concentration. Ten mgkg(-1) melatonin was administered intraperitoneally and showed a stimulatory effect on the enzyme. Time-dependent in vivo studies were conducted for melatonin in Sprague-Dawley type rats. It was found that CA activity in the rat erythrocytes was decreased by the melatonin after 1 and 3 hours to 2500 +/- 500.0 and 1875 +/- 239.4 respectively which were statistically significant (p < 0.05) differences to the control (2660 +/- 235.8). However, CA activity was restored to its normal level after 6h (2666 +/- 235.7) (p > 0.05) probably due to metabolism of the melatonin. The findings indicate that melatonin may be pharmacologically useful in some diseases.  相似文献   
4.
The aim of the study was to examine the effects of zinc supplementation on some hematological parameters. Sixty newborn male broiler chicks were utilized in the study. Zinc (Zn) was added into drinking water at levels of 0, 125, 500, and 1000 mg/kg. In the study, there was no significant difference between control and Zn-supplemented groups in erythrocyte count, hemoglobin amount, hematocrit levels, total leukocyte count, and differential leukocyte % levels, but the α-naphthyl acetate esterase ANAE(+) lymphocyte rate significantly (p<0.05) increased in the 125-ppm Zn-supplemented group compared with the control group. In conclusion, the data obtained may be beneficial in demonstrating the effects of zinc on, at least, these parameters.  相似文献   
5.
In this study, we investigated the levels of serum Zn, Cu, Mg, Mn, Fe, ceruloplasmin (Cp), transferrin (Trf), and albumin in laryngeal carcinoma and correlated their levels with the cancer stage. The sera from 35 patients with laryngeal cancer (10 at stage II, 12 at stage III, and 13 at stage IV) were extracted before treatment and compared with those from the healthy control group (n=15). Although serum Fe and Mn concentrations were lower in the laryngeal cancer groups (for all stages) than in the control group, the difference was not statistically significant (p>0.05). The higher Cu (p<0.001) and Cp (p<0.01) and lower Zn (p<0.01), Mg (p<0.001), and Trf (p<0.01) concentrations were found in laryngeal cancer groups (for each stage) when compared to the control group. In the comparison of stages II, III, and IV (with each other), all parameters were found to be statistically not significant (p>0.05). On the other hand, no meaningful difference was found in terms of the serum albumin level. In our opinion, alterations in the level of trace elements and antioxidant proteins, important for many metabolic processes, in laryngeal cancer may not be a reason for but is, in fact, a consequence of the disease itself.  相似文献   
6.
The remarkable survival ability of Mycobacterium tuberculosis in infected hosts is related to the presence of cell wall-associated mycolic acids. Despite their importance, the mechanisms that modulate expression of these lipids in response to environmental changes are unknown. Here we demonstrate that the enoyl-ACP reductase activity of InhA, an essential enzyme of the mycolic acid biosynthetic pathway and the primary target of the anti-tubercular drug isoniazid, is controlled via phosphorylation. Thr-266 is the unique kinase phosphoacceptor, both in vitro and in vivo. The physiological relevance of Thr-266 phosphorylation was demonstrated using inhA phosphoablative (T266A) or phosphomimetic (T266D/E) mutants. Enoyl reductase activity was severely impaired in the mimetic mutants in vitro, as a consequence of a reduced binding affinity to NADH. Importantly, introduction of inhA_T266D/E failed to complement growth and mycolic acid defects of an inhA-thermosensitive Mycobacterium smegmatis strain, in a similar manner to what is observed following isoniazid treatment. This study suggests that phosphorylation of InhA may represent an unusual mechanism that allows M. tuberculosis to regulate its mycolic acid content, thus offering a new approach to future anti-tuberculosis drug development.  相似文献   
7.
A series of polyphenolic derivatives, including resveratrol, dobutamine, curcumin, catechin and silymarine were investigated for the inhibition of all the catalytically active mammalian isozymes of the metalloprotein carbonic anhydrase (CA, EC 4.2.1.1), that is, CA I–CA XV. These polyphenols effectively inhibited CAs, with KIs in the range of 380 nM–12.02 μM. The various isozymes showed quite diverse inhibition profiles with these compounds, which possess scaffolds not present in other investigated CA inhibitors (CAIs). These data may lead to drug design campaigns of effective CAIs possessing a diverse inhibition mechanism compared to sulfonamide/sulfamate inhibitors, based on such less investigated scaffolds.  相似文献   
8.
Gender differences are related to the manner in which the heart responds to chronic and acute stress conditions of physiological and pathological nature. Depending on dose, sodium selenite acts as an antioxidant proven to have beneficial effects in several pathological conditions G. Drasch, J. Schopfer, and G. N. Schrauzer, Selenium/cadmium ratios in human prostates: indicators of prostate cancer risk of smokers and non-smokers, and relevance to the cancer protective effects of selenium,Biol. Trace Element Res. 103(2), 103–107 (2005); R. G. Kasseroller and G. N. Schrauzer, Treatment of secondary lymphedema of the arm with physical decongestive therapy and sodium selenite: a review,Am. J. Ther. 7(4), 273–279 (2000); G. N. Schrauzer, Anticarcinogenic effects of selenium,Cell. Mol. Life Sci. 57(13–14), 1864–1873 (2000); I. S. Palmer and O. E. Olson, Relative toxicities of selenite and selenate in the drinking water of rats,J. Nutr. 104(3), 306–314 (1974). To date, little is known about the gender-dependent direct effects of toxic doses of selenite on electrophysiology of the cardiovascular system H. A. Schroeder and M. Mitchener, Selenium and tellurium in rats: effect on growth, survival and tumors,J. Nutr. 101(11), 1531–1540 (1971); G. N. Schrauzer, The nutritional significance, metabolism and toxicology of selenomethionine,Adv. Food Nutr. Res. 47, 73–112 (2003). In the present study, the effects of in vitro toxic concentrations of sodium selenite ranging from 10-6 M to 10-3 M were tested on both male and female rat heart preparations. The toxic effects seen in an electrocardiogram and left ventricular pressure were dose and sex dependent at most of the tested concentrations. The present study clearly shows that at toxic doses, stress conditions are induced by selenite, resulting in gender-dependent modifications of the heart function. This modification is more pronounced in the contraction cascade of female rats. Males, on the other hand, had been much more affected in excitation-related parameters.  相似文献   
9.
10.
Although Aβ peptides are causative agents in Alzheimer's disease (AD), the underlying mechanisms are still elusive. We report that Aβ42 induces a translational block by activating AMPK, thereby inhibiting the mTOR pathway. This translational block leads to widespread ER stress, which activates JNK3. JNK3 in turn phosphorylates APP at T668, thereby facilitating its endocytosis and subsequent processing. In support, pharmacologically blocking translation results in a significant increase in Aβ42 in a JNK3-dependent manner. Thus, JNK3 activation, which is?increased in human AD cases and a familial AD (FAD) mouse model, is integral to perpetuating Aβ42 production. Concomitantly, deletion of JNK3 from FAD mice results in a dramatic reduction in Aβ42 levels and overall plaque loads and increased neuronal number and improved cognition. This reveals AD as a metabolic disease that is under tight control by JNK3.  相似文献   
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