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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.
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   
3.
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   
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5.
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   
6.
The dysferlinopathies (e.g. LGMD2b, Myoshi myopathy) are progressive, adult-onset muscle wasting syndromes caused by mutations in the gene coding for dysferlin. Dysferlin is a large (~200kDa) membrane-anchored protein, required for maintenance of plasmalemmal integrity in muscle fibers. To facilitate analysis of dysferlin function in muscle cells, we have established a dysferlin-deficient myogenic cell line (GREG cells) from the A/J mouse, a genetic model for dysferlinopathy. GREG cells have no detectable dysferlin expression, but proliferate normally in growth medium and fuse into functional myotubes in differentiation medium. GREG myotubes exhibit deficiencies in plasma membrane repair, as measured by laser wounding in the presence of FM1-43 dye. Under the wounding conditions used, the majority (~66%) of GREG myotubes lack membrane repair capacity, while no membrane repair deficiency was observed in dysferlin-normal C2C12 myotubes, assayed under the same conditions. We discuss the possibility that the observed heterogeneity in membrane resealing represents genetic compensation for dysferlin deficiency.  相似文献   
7.
The collective migration of cells in the form of cohesive tissues is a hallmark of both morphogenesis and repair. The extrinsic cues that direct these complex migrations usually act by regulating the dynamics of a specific subset of cells, those at the leading edge. Given that normally the function of tissue migration is to lay down multicellular structures, such as branched epithelial networks or sensory organs, it is surprising how little is known about the mechanisms that organize cells behind the leading edge. Cells of the zebrafish lateral line primordium switch from mesenchyme-like leader cells to epithelial rosettes that develop into mechanosensory organs. Here, we show that this transition is regulated by an Fgf signaling circuit that is active within the migrating primordium. Point sources of Fgf ligand drive surrounding cells towards a ;non-leader' fate by increasing their epithelial character, a prerequisite for rosette formation. We demonstrate that the dynamic expression of Fgf ligands determines the spatiotemporal pattern of epithelialization underlying sensory organ formation in the lateral line. Furthermore, this work uncovers a surprising link between internal tissue organization and collective migration.  相似文献   
8.
Although our knowledge about Brucella virulence factors and the host response increase rapidly, the mechanisms of immune evasion by the pathogen and causes of chronic disease are still unknown. Here, we aimed to investigate the immunological factors which belong to CD8+ T cells and their roles in the transition of brucellosis from acute to chronic infection. Using miRNA microarray, more than 2000 miRNAs were screened in CD8+ T cells of patients with acute or chronic brucellosis and healthy controls that were sorted from peripheral blood with flow cytometry and validated through qRT-PCR. Findings were evaluated using GeneSpring GX (Agilent) 13.0 software and KEGG pathway analysis. Expression of two miRNAs were determined to display a significant fold change in chronic group when compared with acute or control groups. Both miRNAs (miR-126-5p and miR-4753-3p) were decreased (p <0.05 or fold change > 2). These miRNAs have the potential to be the regulators of CD8+ T cell-related marker genes for chronic brucellosis infections. The differentially expressed miRNAs and their predicted target genes are involved in MAPK signaling pathway, cytokine-cytokine receptor interactions, endocytosis, regulation of actin cytoskeleton, and focal adhesion indicating their potential roles in chronic brucellosis and its progression. It is the first study of miRNA expression analysis of human CD8+ T cells to clarify the mechanism of inveteracy in brucellosis.  相似文献   
9.
In this study, the possible uses of glassworts as potential food ingredients and their antiproliferative activity against colorectal adenocarcinoma cells together with their antioxidant and phytochemical profiles were investigated for the first time. MeOH extracts of five different taxa collected from different localities were screened for their antioxidant capacities by DPPH (IC50 2.91 – 5.49 mg/ml) and ABTS (24.4 – 38.5 μmol TE/g extract) assays. Salicornia freitagii exhibited the highest DPPH radical scavenging activity. LC/MS/MS analysis displayed that vanillic acid and p‐coumaric acid were two main phenolic compounds in the extract. Salicornia freitagii extracts also exhibited high antiproliferative activity against HT‐29 (IC50 1.67 mg/ml) and Caco‐2 (IC50 3.03 mg/ml) cells for 72 h. Mineral analysis indicated that all the species with different proportions of elemental components contained high amount of cations. These results indicate that investigated glassworts, with their high phenolic and mineral contents and also notable antioxidant and cytotoxic properties, may be utilized as a promising source of therapeutics.  相似文献   
10.
The aim of the present study was to determine the respective role of 1,25-dihydroxyvitamin D3 on vaginal epithelium and 1,25-dihydroxyvitamin D3 receptor expression in ovariectomized rats and vitamin D3 treated rats. Bilateral ovariectomies were performed in 20 mature, non-pregnant Wistar female rats. All the animals were divided into 2 groups consisting of 10 rats each. Group I served as control. In group II, animals were injected intramuscularly with vitamin D3 (50, 00 IU/kg). Two weeks after the injections, vaginas of animals in group I and group II were removed removed and processed for immunohistochemistry. Epithelial differentiation, 1,25-dihydroxyvitamin D3 receptor and cornifin beta expression were investigated in vaginal epithelium of control group (ovariectomized) and vitamin D3 treated rats. Vaginal epithelial cells from vitamin D3 treated animals changed into highly- stratified keratinizing layers. 1,25-dihydroxyvitamin D3 receptor and cornifin beta as a marker of squamous differentiation were present in ovariectomized rats treated with 1,25-dihydroxyvitamin D3. In contrast, cornifin beta and 1,25-dihydroxyvitamin D3 receptor were absent in all layers of vaginal epithelium in control group. We demonstrated for the first time that 1,25-dihydroxyvitamin D3 induced proliferation of vaginal epithelium consistent with the cornifin beta expression and 1,25-dihydroxyvitamin D3 up-regulated 1,25-dihydroxyvitamin D3 receptor expression in vaginal epithelium.  相似文献   
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