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81.
Evidence for ozone formation in human atherosclerotic arteries   总被引:1,自引:0,他引:1  
Here, we report evidence for the production of ozone in human disease. Signature products unique to cholesterol ozonolysis are present within atherosclerotic tissue at the time of carotid endarterectomy, suggesting that ozone production occurred during lesion development. Furthermore, advanced atherosclerotic plaques generate ozone when the leukocytes within the diseased arteries are activated in vitro. The steroids produced by cholesterol ozonolysis cause effects that are thought to be critical to the pathogenesis of atherosclerosis, including cytotoxicity, lipid-loading in macrophages, and deformation of the apolipoprotein B-100 secondary structure. We propose the trivial designation "atheronals" for this previously unrecognized class of steroids.  相似文献   
82.
Won J  Kim M  Yi YW  Kim YH  Jung N  Kim TK 《Science (New York, N.Y.)》2005,309(5731):121-125
Technologies to assess the molecular targets of biomolecules in living cells are lacking. We have developed a technology called magnetism-based interaction capture (MAGIC) that identifies molecular targets on the basis of induced movement of superparamagnetic nanoparticles inside living cells. Efficient intracellular uptake of superparamagnetic nanoparticles (coated with a small molecule of interest) was mediated by a transducible fusogenic peptide. These nanoprobes captured the small molecule's labeled target protein and were translocated in a direction specified by the magnetic field. Use of MAGIC in genome-wide expression screening identified multiple protein targets of a drug. MAGIC was also used to monitor signal-dependent modification and multiple interactions of proteins.  相似文献   
83.
After far-infrared (FIR) radiation onto rice hull, a methanolic extract was prepared for the determination of antioxidant ability. After 30 min of FIR treatment, the radical scavenging activity and total phenol contents of rice hull extracts increased from 47.74 to 79.63% and from 0.12 to 0.19 mM, respectively, compared to control. Inhibition of lipid peroxidation in extracts was also increased from 41.07 to 47.96%. According to the GC-MS analysis, more phenolic compounds (p-coumaric acid, 3-vinyl-1-oxybenzene, p-hydroxybenzaldehyde, vanillin, p-hydroxybenzoic acid, and 4,7-dihydroxyvanillic acid) were detected in FIR-irradiated rice hull extract. These results indicated that FIR radiation onto rice hull could liberate and activate covalently bound phenolic compounds that have antioxidant activities.  相似文献   
84.
Aerobic soil metabolism of a new herbicide,LGC-42153   总被引:1,自引:0,他引:1  
To elucidate the fate of a new sulfonylurea herbicide, LGC-42153 [N-((4,6-dimethoxypyrimidin-2-yl)aminocarbonyl)-2-(1-methoxyacetoxy-2-fluoropropyl)-3-pyridinesulfonamide], in soil, an aerobic soil metabolism study was carried out for 120 days with [(14)C]LGC-42153 applied to a loamy soil. The material balance ranged from 90.7 to 101.5% of applied herbicide. The half-life of [(14)C]LGC-42153 was calculated to be approximately 9.0 days. The degradation products resulted from the cleavage of the sulfonylurea bridge. The metabolites identified during the study were N-((4,6-dimethoxypyrimidin-2-yl)aminocarbonyl)-2-(1-hydroxy-2-fluoropropyl)-3-pyridinesulfonamide, 2-(1-hydroxy-2-fluoropropyl)-3-pyridinesulfonamide, and 4,6-dimethoxy-2-aminopyrimidine. No significant volatile products or [(14)C]carbon dioxide was observed during the study. Nonextractable (14)C-residue reached 14.4-30.5% of applied material at 120 days after treatment, and radioactivity was distributed mostly in the humin and fulvic acid fractions.  相似文献   
85.
Milk vetch dwarf virus (MDV) is an important member of the genus Nanovirus and is transmitted by the aphid Aphis craccivora. MDV has multiple single-stranded DNA genome components, each approximately 1 kb, and two or three alpha-satellite molecules. It mainly infects plants of the legume family Fabaceae. Recently, papaya (Carica papaya) collected in Yesan, South Korea, displaying symptoms of leaf yellowing and dwarfism, was identified as a new host for MDV. To examine the geographical distribution of MDV, papaya samples with symptoms were harvested in South Korea, Vietnam, and Taiwan in August 2018, along with tomato and pepper samples grown in adjacent fields in Vietnam. The results revealed the presence of MDV not only in papaya but also in pepper and tomato. This MDV infection in members of the Solanaceae family was confirmed by Southern blot hybridization performed using a PCR product of segment S as a probe. Based on sequence analysis of three MDV components (M, S, and C3), we verified the presence of three different isolates of MDV in these three countries and homology between sequences of isolates from papaya and from members of the Solanaceae from Vietnam. Taken together, our results clearly demonstrate MDV infection in Vietnam and Taiwan for the first time and confirm that MDV can infect economically important pepper and tomato.  相似文献   
86.
Gnotobiotic piglets were inoculated intralaryngeally with swine Chlamydia trachomatis strain R33 or orally with swine C. trachmatis strain R27. Archived formalin-fixed, paraffin-embedded tissues from piglets euthanatized 4-7 days postinoculation were examined by in situ hybridization for C. trachomatis nucleic acid using a nonradioactive digoxigenin-labeled DNA probes that targeted specific ribosomal RNA or omp1 mRNA molecules of the swine C. trachomatis strains. Positive hybridization signals were detected in bronchial epithelial cells, bronchiolar epithelial cells, pneumocytes, alveolar and interstitial macrophages, and jejunal and ileal enterocytes. Chlamydia-infected cells had a strong signal that was confined to the intracytoplasmic inclusions. Positive hybridization signals were not detected in tissue sections from an uninfected control piglet or in C. psittaci-infected sheep placenta. The morphology of host cells was preserved despite the relatively high temperature required in parts of the incubation procedure. The data indicate that in situ hybridization can be used to detect swine C. trachomatis in formalin-fixed, paraffin-embedded tissue specimens.  相似文献   
87.
To examine the effects on bitterweed toxicity of dietary factors known to increase thiol concentrations in the body, 36 lambs were fed one of the following diets (12 lambs/diet) for a minimum of 9 days prior to bitterweed administration: diet 1, 10% crude protein; diet 2, 20% crude protein, 0.5% methionine, 0.5% sodium sulfate, and 1,102 IU of vitamin E/kg; and diet 3, diet 2 with 0.5% ethoxyquin hydrochloride added. Four lambs fed each diet were euthanatized prior to bitterweed administration (initial euthanasia group). Four lambs fed each diet were administered bitterweed (0.68% hymenoxon, air-dried basis) at a rate of 0.25% of live weight for 5 consecutive days. The remaining four lambs on each diet served as unchallenged controls. In the initial euthanasia group, diet 2 increased extracellular blood thiol concentrations (1.12 vs 0.94 mg of SH/d1, P less than 0.10), rumen fluid thiol concentrations (4.46 vs 1.88 mg of SH/d1, P less than 0.05), and liver thiol concentrations (263.6 vs 109.3 micrograms SH/g of wet wt, P less than 0.05), compared with diet 1. Ethoxyquin hydrochloride (diet 3) reduced blood thiol concentrations (0.94 vs 1.12 mg of SH/dl, P less than 0.10) and liver thiol concentrations (151.6 vs 263.6 micrograms of SH/g of wet wt, P less than 0.05), compared with diet 2. Kidney thiols were unaffected by treatments.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
88.
Chick embryos at 3 to 15 days of incubation were examined for the developmet and differentiation of the "four rings" of the heart. It was clarified that nodes and bundles of the impulse conducting system in the adult chicken were derived from these rings. This finding was very important for understanding the cardiac conducting system in birds and mammals.  相似文献   
89.
The effects of ethylene glycol monoethyl ether (EGEE) on testicular cell populations in rats were investigated by a flow cytometric method. Rats were administered by gavage with EGEE at the various doses of 0 (saline alone), 100, 200, 400, and 800 mg/kg body weight/day for 4 weeks. The treatment of EGEE caused decreases in the weight of testis and epididymis and in the number of testicular cells. Histopathologically, exfoliation of germ cells into the tubular lumen was observed at the doses of above 200 mg/kg. The treatment of EGEE at the dose of 400 mg/kg caused moderate testicular degeneration. A significant depletion of haploid cells and a disproportionate ratio of diploid and tetraploid cells were observed as determined by flow cytometric analysis. These results indicate that the toxic effect of EGEE on the male reproductive system may be strongly associated with the disproportion of testicular germ cells.  相似文献   
90.
Han MG  Kim SJ 《Avian diseases》2003,47(2):261-271
The efficacy of four different commercial live vaccines (vaccines A, B, C, and D) against the infectious laryngotracheitis virus (ILTV) was assessed in specific-pathogen-free (SPF) chickens. SPF chickens were vaccinated intraocularly at 6 wk old with ILTV live vaccines and were challenged intratracheally with the N91B01 strain of virulent Korean ILTV 2 wk after vaccination. The immunity against ILTV live vaccines was assessed by the incidence of latent infection by the challenge virus in the chickens' tracheas and trigeminal ganglia, the reisolation rate of the challenge virus, and the clinical signs in the chickens challenged with the N91B01 strain of ILTV. The latent infection in chickens was assessed by nested polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Our data showed that the clinical signs and challenge virus isolation were negative in all chickens receiving four difference commercial ILTV live vaccines. The viral DNA of the vaccine strain, but not that of the challenge virus, was detected in chickens vaccinated with vaccine A by nested PCR-RFLP. The viral DNAs of both the vaccine and challenge strains were detected from chickens vaccinated with vaccines B, C, and D. This study showed that only vaccine A can protect chickens from latent infection with the field virulent ILTV. We speculate that the efficacy of infectious laryngotracheitis live vaccines to protect chickens from latent infection with virulent ILTVs can be assessed by nested PCR-RFLP analysis.  相似文献   
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