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1.
2-5A is an intracellular effector that has been implicated in interferon action, hormonal regulation, and cell growth control. 2-5A action is mediated through its activation of 2-5A-dependent RNase (RNase L, RNase F). Affinity resins [2-5A-cellulose and core (2-5A)-cellulose] were chemically synthesized for purification and immobilization of 2-5A-dependent RNase from mouse L cells and rabbit reticulocyte lysates. The breakdown of poly(U)-[3'-32P]Cp to acid-soluble fragments was demonstrated using the 2-5A-dependent RNase:2-5A -cellulose complex; this activity was enhanced by adding (free) 2-5A. In contrast, RNase activity was measured from the 2-5A-dependent RNase:core (2-5A)-cellulose complex only after the addition of free 2-5A. The rabbit reticulocyte 2-5A-dependent RNase is activated only by tetramer or higher oligomers of 2-5A; therefore there was breakdown of poly(U)-[3'-32P]Cp using core (2-5A)-cellulose-bound reticulocyte 2-5A-dependent RNase after addition of tetramer 2-5A but there was no poly(U) degradation in the presence of trimer 2-5A. The absence of significant general nuclease in the assays was demonstrated by the resistance to breakdown of poly(C)-[3'-32P]Cp (not susceptible to 2-5A-dependent RNase). Moreover, core (2-5A)-cellulose was used to develop a sensitive (subnanomolar) assay for the detection of authentic 2-5A. 2-5A, or the material to be tested, was added to mouse L-cell 2-5A-dependent RNase:core (2-5A)-cellulose complex in the presence of poly(U)-[3'-32P]Cp. The concentration of 2-5A in the sample could be measured from the amount of poly(U) degradation. Several closely related analogs of 2-5A were tested and found to be completely inactive. The technology described herein may be applied to the study of the regulation of 2-5A-dependent RNase, the detection of 2-5A from cells and tissues, and other aspects of the 2-5A system.  相似文献   

2.
(E)-3',5'-diamino-5-(2-bromovinyl)-2',3',5'-trideoxyuridine (5), the diamino analogue of BVDU (1), was synthesized from BVDU. In contrast with BVDU, compound 5 did not show activity against herpes simplex virus or varicella-zoster virus.  相似文献   

3.

Background

Claudins are the main components of tight junctions, structures which are associated with cell polarity and permeability. The aim of this study was to analyze the expression of claudins 1, 3, 4, 5, and 7 in developing human lung tissues from 12 to 40 weeks of gestation.

Methods

47 cases were analyzed by immunohistochemisty for claudins 1, 3, 4, 5 and 7. 23 cases were also investigated by quantitative RT-PCR for claudin-1, -3 and -4.

Results

Claudin-1 was expressed in epithelium of bronchi and large bronchioles from week 12 onwards but it was not detected in epithelium of developing alveoli. Claudin-3, -4 and -7 were strongly expressed in bronchial epithelium from week 12 to week 40, and they were also expressed in alveoli from week 16 to week 40. Claudin-5 was expressed strongly during all periods in endothelial cells. It was expressed also in epithelium of bronchi from week 12 to week 40, and in alveoli during the canalicular period. RT-PCR analyses revealed detectable amounts of RNAs for claudins 1, 3 and 4 in all cases studied.

Conclusion

Claudin-1, -3, -4, -5, and -7 are expressed in developing human lung from week 12 to week 40 with distinct locations and in divergent quantities. The expression of claudin-1 was restricted to the bronchial epithelium, whereas claudin-3, -4 and -7 were positive also in alveolar epithelium as well as in the bronchial epithelium. All claudins studied are linked to the development of airways, whereas claudin-3, -4, -5 and -7, but not claudin-1, are involved in the development of acinus and the differentiation of alveolar epithelial cells.  相似文献   

4.
A series of N1-nicotinoyl-3- (4-hydroxy-3-methyl phenyl)-5-(substituted phenyl)-2-pyrazolines were synthesized by the reaction between isoniazid (INH) and chalcones and were tested for their in vitro anti-viral activity. Among the compounds, the electron withdrawing group substituted analogues 5-(4-chlorophenyl)-3-(4-hydroxy-3-methylphenyl)-4, 5-dihydro-1H-1- pyrazolyl-4-pyridylmethanone (4b), 5-(2-chlorophenyl)-3-(4-hydroxy-3-methylphenyl)-4,5-dihydro-1H-1-pyrazolyl-4-pyri- dylmethanone (4i), 5-(4-fluorophenyl)-3-(4-hydroxy-3-methylphenyl)-4,5-dihydro- 1H-1-pyrazolyl-4-pyridylmethanone (4h) and 5-(2,6-dichlorophenyl)-3-(4-hydroxy-3-methylphenyl)-4,5-dihydro- 1H-1-pyrazolyl-4-pyridyl methanone (4j) were the most promising and the halogeno function appeared to be essential for antiviral activity.  相似文献   

5.
A series of N1-nicotinoyl-3- (4-hydroxy-3-methyl phenyl)-5-(substituted phenyl)-2-pyrazolines were synthesized by the reaction between isoniazid (INH) and chalcones and were tested for their in vitro anti-viral activity. Among the compounds, the electron withdrawing group substituted analogues 5-(4-chlorophenyl)-3-(4-hydroxy-3-methylphenyl)-4, 5-dihydro-1H-1-pyrazolyl-4-pyridylmethanone (4b), 5-(2-chlorophenyl)-3-(4-hydroxy-3-methylphenyl)-4,5-dihydro-1H-1-pyrazolyl-4-pyridylmethanone (4i), 5-(4-fluorophenyl)-3-(4-hydroxy-3-methylphenyl)-4,5-dihydro-1H-1-pyrazolyl-4-pyridylmethanone (4h) and 5-(2,6-dichlorophenyl)-3-(4-hydroxy-3-methylphenyl)-4,5-dihydro-1H-1-pyrazolyl-4-pyridyl methanone (4j) were the most promising and the halogeno function appeared to be essential for antiviral activity.  相似文献   

6.
Cui Z  Zhang J  Wang F  Wang Y  Miao Z  Chen R 《Carbohydrate research》2008,343(15):2530-2534
A convenient method has been developed for the diastereoselective synthesis of methyl 5-deoxy-5-(dialkylphosphono)-5-(dialkylphosphorylamido)-2,3-O-isopropylidene-beta-d-ribofuranosides under mild conditions, namely the reaction of a dialkyl phosphoramidate with a dialkyl phosphite and methyl 2,3-O-isopropylidene-beta-d-ribo-pentodialdo-1,4-furanoside in acetyl chloride in a one-pot procedure.  相似文献   

7.
The mouse Nkx5-1 and Nkx5-2 genes are related to NK genes in Drosophila and encode proteins with very similar homeodomains. In higher vertebrates Nkx5 genes are specifically expressed in the inner ear. Inactivation of the mouse Nkx5-1 gene by homologous recombination revealed a critical role for the formation of vestibular inner ear structures. Here, we investigated biochemical properties of the proteins encoded by the Nkx5 genes. A similar consensus binding sequence was isolated for both Nkx5 proteins using binding site selection. This sequence is related to target sequences previously identified for other Nkx proteins and contains the conserved homeodomain binding core TAAT. An additional, novel and unrelated high affinity binding sequence could be identified for the Nkx5-2 protein.  相似文献   

8.
Various novel 5-(monosubstituted amino)-2-deoxo-2-phenyl-5-deazaflavins derivatives have been synthesized by direct coupling of 5-deazaflavins and N-alkyl or aryl amines. The antitumor activities against human tumor cell lines CCRF-HSB-2 and KB cells have been investigated in vitro and many compounds showed promising potential antitumor activities with less cytotoxicities. AutoDock molecular docking into PTK (PDB code: 1t46) has been done for lead optimization of these compounds as potential PTK inhibitors. Some of the synthesized 5-(monosubstituted amino)-2-deoxo-2-phenyl-5-deazaflavins at the 5-position exhibited reasonable binding affinities into PTK with the hydrogen bond through their C(5)-NH moiety.  相似文献   

9.
The delta 5,9 fatty acids (5Z,9Z)-5,9-hexadecadienoic acid, (5Z,9Z)-5,9-nonadecadienoic acid, and (5Z,9Z)-5,9-eicosadienoic acid were synthesized for the first time in four steps (9-12% overall yield) starting from commercially available 2-(2-bromoethyl)-1,3-dioxolane. The synthetic approach provided enough material to corroborate the structure and stereochemistry of (5Z,9Z)-5,9-nonadecadienoic acid which was recently identified in the flowers of Malvaviscus arboreus (Malvaceae). The novel phospholipids 1-hexadecanoyl-2-[(5Z,9Z)-5,9-eicosadienoyl]-sn-glycer o-3-phosphocholine and 1-octadecanoyl-2-[(5Z,9Z)-5,9-eicosadienoyl]-sn- glycero-3-phosphocholine were also synthesized from commercially available L-alpha-phosphatidylcholine (egg yolk) and characterized by positive ion electrospray mass spectrometry. These are the first examples of unsymmetrical phospholipids with saturated fatty acids at the sn-1 position and delta 5,9 fatty acids at the sn-2 position.  相似文献   

10.
Structure-activity relationship studies on 3-(5-pyridin-2-yl-2H-tetrazol-2-yl)benzonitrile 2 led to the discovery of 2-(2-[3-(pyridin-3-yloxy)phenyl]-2H-tetrazol-5-yl)pyridine (10)-a highly potent and selective mGlu5 receptor antagonist with good brain penetration and in vivo receptor occupancy in rat and cross-species oral bioavailability.  相似文献   

11.
Human cytomegalovirus-induced DNA polymerase and cellular DNA polymerase alpha were purified by successive chromatography on DEAE-cellulose, phosphocellulose, heparin agarose, and single-stranded DNA agarose columns. The purified virus-induced DNA polymerase was resolved to consist of two polypeptides corresponding to molecular weights of 140,000 and 58,000, as analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Virus-induced DNA polymerase and cellular alpha polymerase were examined for their sensitivities to the triphosphates of 1-(2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl)-5-methyluracil (FMAUTP), -5-iodocytosine (FIACTP), and -5-methylcytosine (FMACTP). The inhibitive effects of these triphosphates on the DNA polymerases were competitive with regard to the natural substrates; thus FMAUTP competes with dTTP, and FIACTP and FMACTP compete with dCTP. The inhibition constants (Ki) for FMAUTP, FIACTP, and FMACTP of virus-induced DNA polymerase are 0.06, 0.30, and 0.47 microM, respectively. Cellular DNA polymerase alpha is much less sensitive to these inhibitors, and its Ki values for FMAUTP, FIACTP, and FMACTP are 0.45, 3.10, and 2.90 microM, respectively. In addition, human cytomegalovirus-induced DNA polymerase, but not cellular DNA polymerase alpha, can utilize these analog triphosphates as alternate substrates for their corresponding natural deoxyribonucleoside triphosphates in in vitro DNA synthesis.  相似文献   

12.
A two-year-old girl has the following features of the cri du chat syndrome: microcephaly, hypertelorism, downward slanting of the palpebral fissures, psychomotor retardation and a cat-like cry. She is only of five patients having the cat cry syndrome with 45 chromosomes. Her karyotype is 45,XX, -5, -14, +t(5; 14)(5qter leads to 5p11: : 14q11 leads to 14qter) with the translocation inherited from her mother and maternal grandmother, each of whom is the carrier of a balanced translocation 46,XX,t(5;14)(p11q11). Normal plasma activity for hexosaminidase B suggests the locus for this enzyme is not located in the delected segment of 5 p.  相似文献   

13.
The adipokine adiponectin is well known to affect the function of immune cells and upregulation of CCL2 by adiponectin in monocytes/macrophages has already been reported. In the current study the effect of adiponectin on CCL2, -3, -4, and -5 and their corresponding receptors CCR1, CCR2, and CCR5 has been analyzed. Adiponectin elevates mRNA and protein of the CC chemokines in primary human monocytes. Simultaneously the surface abundance of CCR2 and CCR5 is reduced while CCR1 is not affected. Downregulation of CCR2 by adiponectin is blocked by a CCR2 antagonist although expression of the CCL2 regulated genes CCR2 and TGF-beta 1 is not altered in the adiponectin-incubated monocytes. CCL2, -3, and -5 concentrations measured in supernatants of monocytes of normal-weight (NW), overweight (OW), and type 2 diabetic (T2D) patients positively correlate with BMI and are increased in obesity and T2D. In contrast CCL4 is similarly abundant in the supernatants of all of these monocytes. The degree of adiponectin-mediated induction of the chemokines CCL3, -4, and -5 negatively correlates with their basal levels and upregulation of CCL3 and CCL5 is significantly impaired in OW and T2D cells. Serum concentrations of these chemokines are almost equal in the three groups and do not correlate with the levels in monocyte supernatants. In conclusion these data demonstrate that adiponectin stimulates release of CCL2 to CCL5 in primary human monocytes, and induction in cells of overweight probands is partly impaired. Adiponectin also lowers surface abundance of CCR2 and CCR5 and downregulation of CCR2 seems to depend on autocrine/paracrine effects of CCL2.  相似文献   

14.
Developmental gradients play a central role in axial patterning in hydra. As part of the effort towards elucidating the molecular basis of these gradients as well as investigating the evolution of the mechanisms underlying axial patterning, genes encoding signaling molecules are under investigation. We report the isolation and characterization of HyBMP5-8b, a BMP5-8 orthologue, from hydra. Processes governing axial patterning are continuously active in adult hydra. Expression patterns of HyBMP5-8b in normal animals and during bud formation, hydra's asexual form of reproduction, were examined. These patterns, coupled with changes in patterns of expression in manipulated tissues during head regeneration, foot regeneration as well as under conditions that alter the positional value gradient indicate that the gene is active in two different processes. The gene plays a role in tentacle formation and in patterning the lower end of the body axis.  相似文献   

15.
The reaction of 5-(1-adamantyl)-1,3,4-oxadiazoline-2-thione 2 with iodoethane, 2-dimethylaminoethyl chloride hydrochloride or 2-piperidinoethyl chloride hydrochloride in ethanolic potassium hydroxide yielded the corresponding 5-(1-adamantyl)-2-ethyl or substituted ethylthio-1,3,4-oxadiazoles 3a-c. Interaction of 2 with formaldehyde solution and primary aromatic amines or 1-substituted piperazines, in ethanol at room temperature yielded the corresponding 5-(1-adamantyl)-3-arylaminomethyl-1,3,4-oxadiazoline-2-thiones 4a-m or 5-(1-adamantyl)-3-(4-substituted-1-piperazinylmethyl)-1,3,4-oxadiazoline-2-thiones 5a-h, respectively. All the synthesized compounds were tested for in vitro activities against certain strains of Gram-positive and Gram-negative bacteria and the yeast-like pathogenic fungus Candida albicans. Compounds 2, 5a, and 5e were found as the most active derivatives, particularly against the Gram-positive bacteria. In addition, the antiviral activity of compounds 2, 4a-m, and 5a-h against HIV-1 using the XTT assay was carried out. Compound 2 produced 100%, 43%, and 37% reduction of viral replication at 50, 10, and 2microg/mL concentrations, respectively.  相似文献   

16.
Utilizing X-ray crystal structure analysis, (3S,5R)-5-[4-(2-chlorophenyl)-2,2-dimethyl-5-oxopiperazin-1-yl]piperidine-3-carboxamides were designed and identified as renin inhibitors. The most potent compound 15 demonstrated favorable pharmacokinetic and pharmacodynamic profiles in rat.  相似文献   

17.
Upregulation of key components of the 2',5'-oligoadenylate (2-5A) synthetase/RNase L pathway has been identified in extracts of peripheral blood mononuclear cells from individuals with chronic fatigue [corrected] syndrome, including the presence of a low molecular weight form of RNase L. In this study, analysis of 2',5'-Oligoadenylate (2-5A) binding and activation of the 80- and 37-kDa forms of RNase L has been completed utilizing photolabeling/immunoprecipitation and affinity assays, respectively. Saturation of photolabeling of the 80- and the 37-kDa RNase L with the 2-5A azido photoprobe, [(32)P]pApAp(8-azidoA), was achieved. Half-maximal photoinsertion of [(32)P]pApAp(8-azidoA) occurred at 3.7 x 10(-8) m for the 80-kDa RNase L and at 6.3 x 10(-8) m for the 37-kDa RNase L. Competition experiments using 100-fold excess unlabeled 2-5A photoaffinity probe, pApAp(8-azidoA), and authentic 2-5A (p(3)A(3)) resulted in complete protection against photolabeling, demonstrating that [(32)P]pApAp(8-azidoA) binds specifically to the 2-5A-binding site of the 80- and 37-kDa RNase L. The rate of RNA hydrolysis by the 37-kDa RNase L was three times faster than the 80-kDa RNase L. The data obtained from these 2-5A binding and 2-5A-dependent activation studies demonstrate the utility of [(32)P]pApAp(8-azidoA) for the detection of the 37-kDa RNase L in peripheral blood mononuclear cell extracts.  相似文献   

18.
Measurements of the 1H NMR spectra of the diastereoisomers of 1-(tetrahydro-2-furanyl)-5-fluorouracil, 3-(tetrahydro-2-furanyl)-5-fluorouracil, and 1,3-bis(tetrahydro-2-furanyl)-5-fluorouracil in the presence of tris[3-(2,2,2-trifluoro-1-hydroxyethylidene)-d-camphorato]europium(Eu(TFC)3) as a chiral shift reagent showed differences between the isomers in the chemical shift changes of the protons of C2'-H and C6-H etc.  相似文献   

19.
9-(5',5'-Difluoro-5'-phosphonopentyl)guanine (DFPP-G) and its hypoxanthine analogue (DFPP-H) were modified by introducing a methyl group to all possible positions of the linker connecting a purine and difluoromethylenephosphonic acid moiety to evaluate the effects of the methyl group on inhibition against purine nucleoside phosphorylase. The methyl group on the linker affected the inhibition in a positional-dependent manner. Inhibitory potency of alpha-methyl and beta-methyl-substituted analogues of DFPP-H increased by about 600- to 1000-fold upon converting to cyclopropane nucleotide analogue (+/-)-4.  相似文献   

20.
1,2-Bis-[2-(5-H/Me/Cl/NO2)-1H-benzimidazolyl]-1,2-ethanediols (L1-L4), 1,4-Bis-[2-(5-H/Me/Cl)-1H-benzimidazolyl]-1,2,3,4-butanetetraols (L5-L7) and their complexes with FeCl3, CuCl2, and AgNO3 were synthesized; antibacterial activity of the compounds was determined toward Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, Shigella flexneri, Proteus mirabilis, and antifungal activity against Candida albicans. The AgI complexes have considerable activity toward the microorganisms. Some AgI complexes show higher activity toward S. epidermidis than AgNO3 and cefuroxime. Cu(L3)Cl2 and Fe(L3)Cl3 show an antifungal effect on C. albicans but L3 itself has no activity.  相似文献   

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