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101.
Prediction of mammalian microRNA targets   总被引:143,自引:0,他引:143  
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Herein we report investigations into the p38alpha MAP kinase activity of trisubstituted imidazoles that led to the identification of compounds possessing highly potent in vivo activity. The SAR of a novel series of imidazopyridines is demonstrated as well, resulting in compounds possessing cellular potency and enhanced in vivo activity in the rat collagen-induced arthritis model of chronic inflammation.  相似文献   
104.
Detachment and incubation of Elodea leaves promoted callose synthesis in all cells, especially in epidermal pits and in sieve tubes. Phloem was detected in the midrib by fluorescent staining of callose induced to form on sieve plates. In EM views of mature sieve elements nucleus and tonoplast were lacking, mictoplasm replaced cytoplasm, mitochondria were fewer in number, and large plastids contained crystalline inclusion bodies. Slime was present as compact aggregates and as individual fibrils in mictoplasm and sieve pores. Deposition of callose is considered in relation to the blockage concept of callose function.  相似文献   
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The construction and operation of a low-cost poultry waste digester   总被引:1,自引:0,他引:1  
A simple and low-cost poultry waste digester (PWD) was constructed to treat the waste from 4000 caged laying hens on University Research Unit No. 2 at North Carolina State University. The system was built basically of a plastic lining with insulation, a heating system, a hot-water tank, and other metering equipment. It was operated at 50 degrees C and pH 7.5-8.0. The initiation of methane production was achieved using the indigenous microflora in the poultry waste. At an optimal loading rate (7.5 kg volatile solids/m(3) day), the PWD produced biogas (55% methane) at a rate of 4.0 m(3)/m(3) day. The PWD was biologically stable and able to tolerate temporary overloads and shutdowns. A higher loading rate failed to maintain a high gas production rate and caused drops in methane content and pH value. Under optimal conditions, a positive energy balance was demonstrated with a net surplus of 50.6% of the gross energy. For methane production, the PWD system was proved to be technically feasible. The simple design and inexpensive materials used for this model could significantly reduce the cost of digestion compared to more conventional systems. More studies are needed to determine the durability, the required maintenance of the system, and the most economical method of biogas and solid residue utilization.  相似文献   
107.

Background

Influenza viruses are a major cause of morbidity and mortality around the world. More recently, a swine-origin influenza A (H1N1) virus that is spreading via human-to-human transmission has become a serious public concern. Although vaccination is the primary strategy for preventing infections, influenza antiviral drugs play an important role in a comprehensive approach to controlling illness and transmission. In addition, a search for influenza-inhibiting drugs is particularly important in the face of high rate of emergence of influenza strains resistant to several existing influenza antivirals.

Methods

We searched for novel anti-influenza inhibitors using a cell-based neutralization (inhibition of virus-induced cytopathic effect) assay. After screening 20,800 randomly selected compounds from a library from ChemDiv, Inc., we found that BPR1P0034 has sub-micromolar antiviral activity. The compound was resynthesized in five steps by conventional chemical techniques. Lead optimization and a structure-activity analysis were used to improve potency. Time-of-addition assay was performed to target an event in the virus life cycle.

Results

The 50% effective inhibitory concentration (IC50) of BPR1P0034 was 0.42 ± 0.11 μM, when measured with a plaque reduction assay. Viral protein and RNA synthesis of A/WSN/33 (H1N1) was inhibited by BPR1P0034 and the virus-induced cytopathic effects were thus significantly reduced. BPR1P0034 exhibited broad inhibition spectrum for influenza viruses but showed no antiviral effect for enteroviruses and echovirus 9. In a time-of-addition assay, in which the compound was added at different stages along the viral replication cycle (such as at adsorption or after adsorption), its antiviral activity was more efficient in cells treated with the test compound between 0 and 2 h, right after viral infection, implying that an early step of viral replication might be the target of the compound. These results suggest that BPR1P0034 targets the virus during viral uncoating or viral RNA importation into the nucleus.

Conclusions

To the best of our knowledge, BPR1P0034 is the first pyrazole-based anti-influenza compound ever identified and characterized from high throughput screening to show potent (sub-μM) antiviral activity. We conclude that BPR1P0034 has potential antiviral activity, which offers an opportunity for the development of a new anti-influenza virus agent.  相似文献   
108.
Exposure to air pollution [particulate matter, particles <10 microm (PM(10))] causes a systemic inflammatory response that includes stimulation of the bone marrow (BM) and progression of atherosclerosis. Monocytes are known to play a key role in atherogenesis by migration into subendothelial lesions where they appear as foam cells. The present study was designed to quantify the BM monocyte response in Watanabe heritable hyperlipidemic (WHHL) rabbits after PM(10) exposure. WHHL rabbits were given twice weekly intrapharyngeal instillations of 5 mg of PM(10) for 4 wk to a total of 40 mg and compared with control WHHL or New Zealand White (NZW) rabbits. The thymidine analog 5'-bromo-2'-deoxyuridine was used to label dividing cells in the BM and a monoclonal antibody to identify monocytes in peripheral blood. The transit time of monocytes through the BM was faster in WHHL than in NZW rabbits (30.4 +/- 1.9 h vs. 35.2 +/- 0.9 h, WHHL vs. NZW; P < 0.05). PM(10) instillation exposure increased circulating band cell counts, caused rapid release of monocytes from the BM, and further shortened their transit time through the BM to 23.2 +/- 1.6 h (P < 0.05). The percentage of alveolar macrophages containing particles in the lung correlated with the BM transit time of monocytes (r(2) = 0.45, P <0.05). We conclude that atherosclerosis increases the release of monocytes from the BM, and PM(10) exposure accelerates this process in relation to the amount of particles phagocytosed by alveolar macrophages.  相似文献   
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