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111.
The discovery of threosyl phosphonate nucleoside (PMDTA, EC50 = 2.53 μM) as a potent anti-HIV agent has led to the synthesis and biological evaluation of 5 ′-deoxyversions of threosyl phosphonate nucleosides from 1,4-dihydroxy-2-butene. The synthesized nucleoside phosphonic acid analogues 14 and 19 were tested for anti-HIV activity as well as cytotoxicity. The adenine analogue 14 exhibits moderate in vitro anti-HIV-1 activity (EC50 = 12.6 μM).  相似文献   
112.
Novel syntheses of 4′-modified cyclopentenyl pyrimidine C-nucleosides were performed via C-C bond formation using SN2 alkylation via the key intermediate mesylates 6 and 16, which were prepared from acyclic ketone derivatives. When antiviral evaluation of synthesized compound was performed against various viruses such as HIV-1, HSV-1 and HSV-2, isocytidine analogue 20 showed moderate anti-HIV activity in CEM cell line (EC50 = 13.1 μmol).7  相似文献   
113.
Novel vinyl branched apiosyl nucleosides were synthesized in this study. Apiosyl sugar moiety was constructed by sequential ozonolysis and reductions. The bases (uracil and thymine) were efficiently coupled by glycosyl condensation procedure (persilyated base and TMSOTf). The antiviral activities of the synthesized compounds were evaluated against the HIV-1, HSV-1, HSV-2, and HCMV. Compound 10β displayed moderate anti-HIV activity (EC50 = 17.3 μg/mL) without exhibiting any cytotoxicity up to 100 μM.  相似文献   
114.
115.
Amethanolic extract of Dipsacus asper, having anti-diabetic activity, was examined as a possible aldose reductase (ALR2) inhibitor, a key enzyme involved in diabetic complications. Bioactivity guided fractionation led to the isolation of ten compounds, ursolic acid (1), oleanolic acid-3-O-α-L-arabinopyranoside (2), daucosterol (3), hederagenin-3-O-α-L-arabinopyranoside (4), sweroside(5), caffeic acid (6), esculetin (7), protocatechualdehyde (8), loganin (9), and vanilic acid (10) from the ethyl acetate fraction of D. asper methanol extract. Among them, compounds 4, 6, 7, and 8 exhibited inhibitory effects on aldose reductase, with IC50 values of 23.70, 16.71, 34.36, and 21.81 μM, respectively. This is the first report on the isolation of these compounds from D. asper, and the ALR2 inhibitory activity of hederagenin-3-O-α-L-arabinopyranoside. These results suggest the successful use of the extract of D. asper for ameliorating diabetic complications.  相似文献   
116.
A series of naphthoquinone-benzothiazole conjugates were synthesized as algicides, and their efficacies against harmful algal blooming species, such as Chattonella marina, Heterosigma akashiwo and Cochlodinium polykrikoides, were examined. The introduction of substituted benzothiazole at the C2 position of 1,4-naphthoquinone (compounds 19) resulted in higher algicidal activity against C. polykrikoides than the C6 conjugates (compounds 1020). On the other hand, of the C6 conjugates, compounds 11 and 12 exhibited better algicidal activity against H. akashiwo, C. marina, and C. polykrikoides than the C2 conjugates. Further structure-activity analysis indicated that a replacement of the methoxy groups with hydroxyl groups (compounds 2126) decreased the algicidal activity significantly. Among the various synthetic naphthoquinonebezothiazole conjugates tested, compound 12 was found to affect the most significant decrease in the level of C. polykrikoides growth, with an IC50 of 0.19 μM. Compound 11 was found to be the most potent inhibitor against H. akashiwo and C. polykrikoides, with IC50 values of 0.32 and 0.12 μM, respectively. Overall, these results highlight a possible method for controlling and inhibiting red tide forming algae using NQ derivatives.  相似文献   
117.
This study aimed to elucidate the mechanisms that may lead to an efficient strategy to induce a suitable host response of the vaginal mucosa upon exposure to intravaginally delivered exogenous compounds. It was hypothesized that the upregulation of intercellular adhesion molecule (ICAM)-1 gene expression may reflect the inflammatory response evoked by exogenous compounds. Major emphasis was placed on ethylenediamine tetraacetic acid (EDTA) which was added as a synergistic agent to conventional spermicidal agents or anti-HIV drugs. The levels of ICAM-1 mRNA were examined as a surrogate marker for inflammatory response in human vaginal epithelial cells upon exposure to EDTA or interleukin (IL)-1β (i.e. positive control, 25 mM). The effects of estrogen on EDTA-induced ICAM-1 expression were also evaluated for the estrogen involvement in the inflammatory process of the vaginal mucosa. ICAM-1 expression in human vaginal cells (VK2/E6E7 cells) increased as EDTA concentration added to human vaginal cell lines increased. The effects of estrogen on EDTA-induced ICAM-1 expression in human vaginal epithelial cells were estrogen-concentration dependent; estrogen at lower concentrations (~1–10 nM) did not affect ICAM-1 expression, whereas estrogen at higher concentrations (~100 nM–1 µM) attenuated ICAM-1 expression. The influence of estrogen in ICAM-1 expression suggests the beneficial effects of estrogen on the regulation of vaginal homeostasis. Identification and quantification of specific surrogate markers for the inflammatory response evoked by exogenous compounds and their regulation by estrogen will lead to an efficient strategy against sexually transmitted diseases including AIDS.  相似文献   
118.
Muskmelon (Cucumis melo L.) wilt caused by Fusarium oxysporum f. sp. melonis leads to severe economic losses. A bio-organic fertilizer (BIO) fortified with an antagonistic strain of Bacillus subtilis Y-IVI was used to control this disease. Pot experiments were carried out to investigate the efficacy and to elucidate biocontrol mechanisms for the disease. BIO significantly reduced the disease incidence. Population of F. oxysporum in plant shoots of the BIO treatment were about 1000-fold lower than the control. Population of Y-IVI remained high in muskmelon rhizosphere of the BIO treatment during the experiment. Concentration of antifungal lipopeptides, iturin A, in the BIO treatment was significantly higher than other treatments. Ten days after transplantation, the salicylic acid content in BIO-treated plant leaves was significantly higher than control. In conclusion, BIO effectively controlled muskmelon wilt, possibly because the antagonistic microbes effectively colonize the plant rhizosphere and shoots to preclude pathogen invasion. Furthermore, Y-IVI produces antifungal lipopeptides in the rhizosphere.  相似文献   
119.
Background aimsMany rodent experiments and human studies on stem cell therapy have shown promising therapeutic approaches to liver diseases. We investigated the clinical outcomes of five patients with liver failure of various causes who received autologous CD34-depleted bone marrow-derived mononuclear cell (BM-MNC) transplantation, including mesenchymal stromal cells, through the hepatic artery.MethodsCD34-depleted BM-MNCs were obtained from five patients waiting for liver transplantation by bone marrow aspiration and using the CliniMACS CD34 Reagent System (Miltenyi Biotech, Bergisch Gladbach, Germany), and autologous hepatic artery infusion was performed. The causes of hepatic decompensation were hepatitis B virus (HBV), hepatitis C virus (HCV), propylthiouracil-induced toxic hepatitis and Wilson disease.ResultsSerum albumin levels improved 1 week after transplantation from 2.8 g/dL, 2.4 g/dL, 2.7 g/dL and 1.9 g/dL to 3.3 g/dL, 3.1 g/dL, 2.8 g/dL and 2.6 g/dL. Transient liver elastography data showed some change from 65 kPa, 33 kPa, 34.8 kPa and undetectable to 46.4 kPa, 19.8 kPa, 29.1 kPa and 67.8 kPa at 4 weeks after transplantation in a patient with Wilson disease, a patient with HCV, and two patients with HBV. Ascites decreased in two patients. One of the patients with HBV underwent liver transplantation 4 months after the infusion, and the hepatic progenitor markers (cytokeratin [CD]-7, CD-8, CD-9, CD-18, CD-19, c-Kit and epithelial cell adhesion molecule [EpCAM]) were highly expressed in the explanted liver.ConclusionsSerum albumin levels, liver stiffness, liver volume, subjective healthiness and quality of life improved in the study patients. Although these findings were observed in a small population, the results may suggest a promising future for autologous CD34-depleted BM-MNC transplantation as a bridge to liver transplantation in patients with liver failure.  相似文献   
120.
Resting state functional magnetic resonance imaging (fMRI) has been commonly used to measure functional connectivity between cortical regions, while diffusion tensor imaging (DTI) can be used to characterize structural connectivity of white matter tracts. In principle combining resting state fMRI and DTI data could allow characterization of structure-function relations of distributed neural networks. However, due to differences in the biophysical origins of their signals and in the tissues to which they apply, there has been no direct integration of these techniques to date. We demonstrate that MRI signal variations and power spectra in a resting state are largely comparable between gray matter and white matter, that there are temporal correlations of fMRI signals that persist over long distances within distinct white matter structures, and that neighboring intervoxel correlations of low frequency resting state signals showed distinct anisotropy in many regions. These observations suggest that MRI signal variations from within white matter in a resting state may convey similar information as their corresponding fluctuations of MRI signals in gray matter. We thus derive a local spatio-temporal correlation tensor which captures directional variations of resting-state correlations and which reveals distinct structures in both white and gray matter. This novel concept is illustrated with in vivo experiments in a resting state, which demonstrate the potential of the technique for mapping the functional structure of neural networks and for direct integration of structure-function relations in the human brain.  相似文献   
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