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971.
972.
Protection of rhesus monkeys against infection with minimally pathogenic simian-human immunodeficiency virus: correlations with neutralizing antibodies and cytotoxic T cells
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Quinnan GV Yu XF Lewis MG Zhang PF Sutter G Silvera P Dong M Choudhary A Sarkis PT Bouma P Zhang Z Montefiori DC Vancott TC Broder CC 《Journal of virology》2005,79(6):3358-3369
We studied the capacity of active immunization of rhesus monkeys with HIV-1 envelope protein (Env) to induce primary virus cross-reactive neutralizing antibodies to prevent infection following intravenous challenge with simian-human immunodeficiency virus (SHIV). Monkeys were immunized with the human immunodeficiency type 1 (HIV-1) strain R2 Env. Initially, the Env was expressed in vivo by an alphavirus replicon particle system, and then it was administered as soluble oligomeric gp140. Concurrently, groups of monkeys received expression vectors that encoded either simian immunodeficiency virus (SIV) gag/pol genes or no SIV genes in vivo to test the additional protective benefit of concurrent induction of virus-specific cell-mediated immune (CMI) responses. Groups of control monkeys received either the gag/pol regimen or sham immunizations. The antibodies induced by the Env immunization regimen neutralized diverse primary HIV-1 strains. Similarly, potent CMI responses were induced by the gag/pol regimen, as measured by gamma interferon enzyme-linked immunospot assays. Differences in the responses among groups of monkeys strongly suggested that there was interference between the Env and gag/pol immunization regimens. Complete protection of some of the monkeys against infection after intravenous challenge with the partially pathogenic SHIV(DH12R (Clone 7)) was associated independently with both neutralizing antibody and CMI responses. Protection was associated with SHIV(DH12 (Clone 7)) serum neutralizing antibody titers of > or =1:80 or with cellular immune responses corresponding to >2,000 spot forming cells per 10(6) peripheral blood mononuclear cells. Immunization was also associated with a reduction in the magnitude and duration of virus load. Induction of cross-reactive, primary HIV-1-neutralizing antibodies is feasible and, when potent, may result in complete protection against infection with a heterologous challenge virus strain. 相似文献
973.
Jang Hoon Kim Nguyen Phuong Thao Yoo Kyong Han Young Suk Lee Bui Thi Thuy Luyen Ha Van Oanh 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):1174-1180
Cholinesterases (ChEs) are enzymes that break down neurotransmitters associated with cognitive function and memory. We isolated cinnamic acids (1 and 2), indolinones (3 and 4), and cycloartane triterpenoid derivatives (5–19) from the roots of Cimicifuga dahurica (Turcz.) Maxim. by chromatography. These compounds were evaluated for their inhibitory activity toward ChEs. Compound 1 was determined to have an IC50 value of 16.7?±?1.9?μM, and to act as a competitive inhibitor of acetylcholinesterase (AChE). Compounds 3, 4 and 14 were found to be noncompetitive with IC50 values of 13.8?±?1.5 and 6.5?±?2.5?μM, and competitive with an IC50 value of 22.6?±?0.4?μM, respectively, against butyrylcholinesterase (BuChE). Our molecular simulation suggested each key amino acid, Tyr337 of AChE and Asn228 of BuChE, which were corresponded with potential inhibitors 1, and 3 and 4, respectively. Compounds 1 and 4 were revealed to be promising compounds for inhibition of AChEs and BuChEs, respectively. 相似文献
974.
Anh Q. Vo Herman He Jiaxiang Zhang Scott Martin Rui Chen Michael A. Repka 《AAPS PharmSciTech》2018,19(8):3425-3429
Continuous manufacturing, a gaining interest paradigm in the pharmaceutical industry, requires in-process monitoring of critical process parameters to ensure product consistency. This study demonstrated the application of Fourier transform near-infrared (FT-NIR) spectroscopy in conjunction with chemometrics modeling for in-line hot melt extrusion process monitoring. The obtained results suggested that inline FT-NIR analysis, along with a tailored NIR reflector, is a viable process analytical tool to monitor active pharmaceutical ingredient concentration as well as processing parameters. 相似文献
975.
Marcus M. Seldin Simon Koplev Prashant Rajbhandari Laurent Vergnes Gregory M. Rosenberg Yonghong Meng Calvin Pan Thuy M.N. Phuong Raffi Gharakhanian Nam Che Selina Mäkinen Diana M. Shih Mete Civelek Brian W. Parks Eric D. Kim Frode Norheim Karthickeyan Chella Krishnan Yehudit Hasin-Brumshtein Aldons J. Lusis 《Cell metabolism》2018,27(5):1138-1155.e6
976.
Revathy Sankaran Pau Loke Show Yu-Shen Cheng Yang Tao Xia Ao Thi Dong Phuong Nguyen Dong Van Quyen 《Molecular biotechnology》2018,60(10):749-761
Microalgae are the most promising sources of protein, which have high potential due to their high-value protein content. Conventional methods of protein harnessing required multiple steps, and they are generally complex, time consuming, and expensive. Currently, the study of integration methods for microalgae cell disruption and protein recovery process as a single-step process is attracting considerable interest. This study aims to investigate the novel approach of integration method of electrolysis and liquid biphasic flotation for protein extraction from wet biomass of Chlorella sorokiniana CY-1 and obtaining the optimal operating conditions for the protein extraction. The optimized conditions were found at 60% (v/v) of 1-propanol as top phase, 250 g/L of dipotassium hydrogen phosphate as bottom phase, crude microalgae loading of 0.1 g, air flowrate of 150 cc/min, flotation time of 10 min, voltage of 20 V and electrode’s tip touching the top phase of LBEF. The protein recovery and separation efficiency after optimization were 23.4106?±?1.2514% and 173.0870?±?4.4752%, respectively. Comparison for LBEF with and without the aid of electric supply was also conducted, and it was found that with the aid of electrolysis, the protein recovery and separation efficiency increased compared to the LBEF without electrolysis. This novel approach minimizes the steps for overall protein recovery from microalgae, time consumption, and cost of operation, which is beneficial in bioprocessing industry. 相似文献
977.
978.
Service Lifetime,Storage Time,and Disposal Pathways of Electronic Equipment: A Swiss Case Study
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Esther Thiébaud Lorenz M. Hilty Mathias Schluep Rolf Widmer Martin Faulstich 《Journal of Industrial Ecology》2018,22(1):196-208
Product lifetime is an essential aspect of dynamic material flow analyses and has been modeled using lifetime distribution functions, mostly average lifetimes. Existing data regarding the lifetime of electronic equipment (EE) are based on diverging definitions of lifetime as well as different temporal and regional scopes. After its active use, EE is often not disposed of immediately, but remains in storage for some time. Specific data on the share of EE that is stored and the time they remain in storage are scarce. This article investigates the service lifetime, storage time, and disposal pathways of ten electronic device types, based on data from an online survey complemented by structured interviews. We distinguish between new and secondhand devices and compute histograms, averages, and medians of the different lifetimes and their change over time. The average service lifetime varies from 3.3 years for mobile phones to 10.8 years for large loudspeakers, the average storage time from 0.8 years for flat panel display televisions to 3.6 years for large loudspeakers. Most service lifetime histograms are positively skewed and show substantial differences among device types. The storage time histograms, being more similar to one another, indicate that the storage behavior is similar for most device types. The data on disposal pathways show that a large proportion of devices are stored and reused before they reach the collection scheme. 相似文献
979.
Thi‐Anh Pham Imran Shair Mohammad Van‐Tuan Vu Xiao‐Long Hu Chaurasiya Birendra Aftab Ulah Cui Guo Xian‐Yu Lü Wen‐Cai Ye Hao Wang 《化学与生物多样性》2018,15(6)
A new phloroglucinol derivative, named eucalyptin B ( 1 ), along with five related known compounds ( 2 – 6 ), was isolated from the fruits of Eucalyptus globulus. Their structures were elucidated by means of 1D‐ and 2D‐NMR spectroscopy, with the absolute configuration of 1 determined by electronic circular dichroism (ECD) calculations. All isolated compounds ( 1 – 6 ) were evaluated for their cytotoxic activities against lung (A549), breast (4T1), and skin (B16F10) cancer cell lines. On the basis of cell viability assay, the cytotoxic activity of eucalyptin B ( 1 ) was further confirmed by apoptosis assay. Additionally, after treatment with eucalyptin B ( 1 ), the apoptosis factor proteins (Bcl2 and Bax) and caspase‐3 levels in A549 cells were also determined by Western‐blot analysis. By cytotoxic assay, eucalyptin B ( 1 ) exhibited potent cytotoxicity against A549 cells with an IC50 value of 1.51 μm and induced concentration dependent apoptosis of up to 49%. Additionally, eucalyptin B ( 1 ) inhibited 5‐fold and increased 10‐folds in the level of Bcl2 and Bax, respectively. Furthermore, the 11‐fold increase in the level of caspase‐3 confirmed eucalyptin B ( 1 ) activated caspase dependent apoptosis pathway. In conclusion, the isolated compound eucalyptin B ( 1 ) has promising cytotoxic activity in tumor cells, especially in A549. 相似文献
980.
A simple, rapid procedure to generate an oxygen-reduced atmosphere suitable for growing Campylobacter jejuni was investigated. A modified AnaeroGenTM system (MAS), consisting of a single AnaeroGenTM anaerobic sachet AM35 (Oxoid Unipath Ltd., Basingstoke, UK) activated in a 9 L anaerobic jar (BBL, Cockeysville, MD), was evaluated and compared with the conventional gassed jar system described in the 8th edition of the U.S. Food and Drug Administration's Bacteriological Analytical Manual (BAM). Enriched cultures of C. jejuni (six replicates at each of five inoculum levels: 10-2 to 102 cfu/mL in artificially contaminated raw milk, raw oyster, crab meat, or mushroom were streaked in duplicate onto four different selective isolation agars for simultaneous incubation in MAS and in the BAM system. No significant differences (p > 0. 05) in recovery rates of C. jejuni were observed for the two systems. The type of isolation agar used did not affect these recovery rates. The quality of growth of C. jejuni at 24, 48 or 72 h was similar in both systems. MAS successfully reduced atmospheric oxygen to a level suitable for the growth of C. jejuni. It was simple and rapid compared to the BAM system, and cost-effective compared to the Oxoid CampyGenTM system specifically designed for the growth of Campylobacter spp. 相似文献