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131.
(2-Bromo-3,4-dimethoxyphenyl) (3,4-dimethoxyphenyl)methanone (10) and its derivatives with Br, one dibromide and isomeric three tribromides, were synthesized. Demethylation of these compounds afforded a series of new bromophenols. Inhibition of human cytosolic carbonic anhydrase II (hCA II) isozyme by these new bromophenols and naturally occurring 3,4,6-tribromo-5-(2,5-dibromo-3,4-dihydroxybenzyl)benzene-1,2-diol (3), and 5,5'-methylenebis(3,4,6-tribromo-benzene-1,2-diol) (4) was investigated. The synthesized compounds showed carbonic anhydrase inhibitory capacities with IC(50) values in the range of 0.7-372 μM against hCA II. Some bromophenols investigated here showed effective hCA II inhibitory activity and might be used as leads for generating novel carbonic anhydrase inhibitors which are valuable drug candidates for the treatment of glaucoma, epilepsy, gastric and duodenal ulcers, neurological disorders, or osteoporosis.  相似文献   
132.
Studies on carbonic anhydrase (CA, EC 4.2.1.1) inhibitors have increased due to several therapeutic applications while there are few investigations on activators. Here we investigated CA inhibitory and activatory capacities of a series of dopaminergic compounds on human carbonic anhydrase (hCA) isozymes I, II, and VI. 2-Amino-1,2,3,4-tetrahydronaphthalene-6,7-diol hydrobromide and 2-amino-1,2,3,4-tetrahydronaphthalene-5,6-diol hydrobromide were found to show effective inhibitory action on hCA I and II whereas 2-amino-5,6-dibromoindan hydrobromide and 2-amino-5-bromoindan hydrobromide exhibited only moderate inhibition against both isoforms, being more effective inhibitors of hCA VI. K(i) values of the molecules 3-6 were in the range of 41.12-363 μM against hCA I, of 0.381-470 μM against hCA II and of 0.578-1.152 μM against hCA VI, respectively. Compound 7 behaved as a CA activator with K(A) values of 27.3 μM against hCA I, of 18.4 μM against hCA II and of 8.73 μM against hCA VI, respectively.  相似文献   
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ABSTRACT: BACKGROUND: Coral reefs are areas of maximum biodiversity, but the parasites of coral reef fishes, and especially their species richness, are not well known. Over an 8-year period, parasites were collected from 24 species of Lutjanidae, Nemipteridae and Caesionidae off New Caledonia, South Pacific. RESULTS: Host-parasite and parasite-host lists are provided, with a total of 207 host-parasite combinations and 58 parasite species identified at the species level, with 27 new host records. Results are presented for isopods, copepods, monogeneans, digeneans, cestodes and nematodes. When results are restricted to well-sampled reef fish species (sample size[THIN SPACE]>[THIN SPACE]30), the number of host-parasite combinations is 20[EN DASH]25 per fish species, and the number of parasites identified at the species level is 9[EN DASH]13 per fish species. Lutjanids include reef-associated fish and deeper sea fish from the outer slopes of the coral reef: fish from both milieus were compared. Surprisingly, parasite biodiversity was higher in deeper sea fish than in reef fish (host-parasite combinations: 12.50 vs 10.13, number of species per fish 3.75 vs 3.00); however, we identified four biases which diminish the validity of this comparison. Finally, these results and previously published results allow us to propose a generalization of parasite biodiversity for four major families of reef-associated fishes (Lutjanidae, Nemipteridae, Serranidae and Lethrinidae): well-sampled fish have a mean of 20 host-parasite combinations per fish species, and the number of parasites identified at the species level is 10 per fish species. CONCLUSIONS: Since all precautions have been taken to minimize taxon numbers, it is safe to affirm than the number of fish parasites is at least ten times the number of fish species in coral reefs, for species of similar size or larger than the species in the four families studied; this is a major improvement to our estimate of biodiversity in coral reefs. Our results suggest that extinction of a coral reef fish species would eventually result in the coextinction of at least ten species of parasites.  相似文献   
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Therapeutic effect of interferon-β (IFN-β) treatment has been associated with modulation of the balance between Th1, Th17, Th2 and regulatory T (Treg) cells, whereas the impact of disease modifying drugs on Th9-immunity in multiple sclerosis (MS) has not been studied. To investigate the short-term effects of IFN-β treatment on cytokines in MS, we determined serum levels of IL-17, IL-23, IL-10, IL-4, IFN-γ, IL-9 and TGF-β in relapsing remitting MS patients before and 2 months after IFN-β treatment by ELISA. MS patients showed increased IL-17, IL-23 and IL-4 levels and decreased IL-9 levels as compared to healthy controls. IFN-β treatment only reduced IL-17 and IL-23 levels, whereas the levels of other cytokines remained unchanged. IFN-β treatment appears to exert its earliest therapeutic effect on Th17-immunity. The influence of IL-9 on MS pathogenesis needs to be further studied.  相似文献   
137.
Ek C  Whary MT  Ihrig M  Bravo LE  Correa P  Fox JG 《Helicobacter》2012,17(2):107-115
Background: Helicobacter pylori‐infected children from coastal Tumaco, Colombia, have more parasitism, and adults have lower gastric cancer risk compared with high‐altitude Pasto/Tuquerres residents. Because helminth and Toxoplasma gondii infections alter helicobacter gastritis in rodent models, we determined whether seropositivity to Ascaris lumbricoides or T. gondii was associated with Th2‐IgG1 or Th1‐IgG2 responses to H. pylori. Methods: Sera (240) from the two populations were evaluated for A. lumbricoides and T. gondii seropositivity and results correlated with IgE and IgG isotype responses to H. pylori. Results: Most Tumaco children and adults were seropositive for A. lumbricoides (89%, 66%), T. gondii (59%, 98%), or both (45%, 66%). In contrast, seropositivity among Pasto/Tuquerres children was much lower (9%A. lumbricoides, 11%T. gondii, and 2% dual positive) but increased in adults (58%A. lumbricoides, 82%T. gondii, and 41% dual positive). A. lumbricoides seropositivity correlated with elevated IgE and anti‐inflammatory Th2‐IgG1 responses to H. pylori, while T. gondiigondii seropositivity was linked to elevated IgE, pro‐inflammatory Th1‐IgG2, IgG3, and IgG4 responses to H. pylori. Individuals with high T. gondii titers had reduced Th1‐IgG2, IgG3, and IgG4 responses to H. pylori. Conclusions: Results support regional differences for childhood parasitism and indicate A. lumbricoides and T. gondii infections may impact inflammatory responses to H. pylori and partially explain differences in gastric cancer risk in Colombia.  相似文献   
138.
This study was designed to investigate whether the short-term extracorporeal shockwave lithotripsy (ESWL) exposure to kidney produces an oxidative stress and a change in some trace element levels in liver and diaphragm muscles of rats. Twelve male Wistar albino rats were divided randomly into two groups, each consisting of six rats. The animals in the first group did not receive any treatment and served as control group. The right-side kidneys of animals in group 2 were treated with two-thousand 18 kV shock waves while anesthetized with 50 mg kg(-1) ketamine. The localization of the right kidney was achieved after contrast medium injection through a tail vein under fluoroscopy control. The animals were killed 72 h after the ESWL treatment, and liver and diaphragm muscles were harvested for the determination of tissue oxidative stress and trace element levels. Although the malondialdehyde level increased, superoxide dismutase and glutathione peroxidase enzyme activities decreased in the livers and diaphragm muscles of ESWL-treated rats. Although glutathione level increased in liver, it decreased in diaphragm muscles of ESWL-treated animals. Fe, Mg and Mn levels decreased, and Cu and Pb levels increased in the livers of ESWL-treated animals. Fe and Cu levels increased, and Mg, Pb, Mn and Zn levels decreased in the diaphragm muscles of ESWL-treated animals. It also causes a decrease or increase in many mineral levels in liver and diaphragm muscles, which is an undesirable condition for the normal physiological function of tissues.  相似文献   
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140.
In this study, we aimed to investigate the distribution pattern of ubiquitin and p97/VCP in the rat retina during postnatal development. Eyeballs from 1-, 4-, 10-, 36- and 72-week-old rats were examined by immunohistochemistry, and protein colocalization was determined by immunofluorescence microscopy. In the 1-week-old rat retina, p97/VCP was strongly expressed in the neuroblast layer, however no ubiquitin immunoreactivity was observed. p97/VCP immunoreactivity was present in the ganglion cell layer (GCL), inner nuclear layer (INL), outer nuclear layer (ONL), inner segment (IS) of the photoreceptor layer, and retinal pigment epithelium in the 4- and 10-week-old rat retinas. p97/VCP immunoreactivity increased significantly in the 10-week-old rat retinas. Ubiquitin was barely seen in the 4-week-old rat retinas, and ubiquitin expression was weak in the GCL and the IPL of the 10-week-old rat retinas. In the 36- and 72-week-old rats, the presence of ubiquitin was remarkable in the IS, INL, IPL and GCL, however, p97/VCP immunoreactivity was significantly decreased. Colocalization of ubiquitin and p97/VCP was also observed in the INL, IS, GCL and ONL of 36- and 72-week-old rat retinas. Our results indicate that p97/VCP immunoreactivity in the retina significantly decreases after rats reach 10 weeks of age, whereas ubiquitin immunoreactivity increases with aging. These results suggest that an altered expression pattern of p97/VCP and ubiquitin in the developing rat retina may associate with age-related retinal degeneration.  相似文献   
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