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Plasmonics - This study shows development of highly sensitive and stable localized surface plasmon resonance (LSPR)-active U-bent glass and polymeric optical fiber (GOF and POF) sensor probes by a... 相似文献
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Dukka B KC 《BMC structural biology》2009,9(1):12-9
Background
Common structural biology methods (i.e., NMR and molecular dynamics) often produce ensembles of molecular structures. Consequently, averaging of 3D coordinates of molecular structures (proteins and RNA) is a frequent approach to obtain a consensus structure that is representative of the ensemble. However, when the structures are averaged, artifacts can result in unrealistic local geometries, including unphysical bond lengths and angles. 相似文献4.
Mijia Lu Yuexiu Zhang Piyush Dravid Anzhong Li Cong Zeng Mahesh KC Sheetal Trivedi Himanshu Sharma Supranee Chaiwatpongsakorn Ashley Zani Adam Kenney Chuanxi Cai Chengjin Ye Xueya Liang Jianming Qiu Luis Martinez-Sobrido Jacob S. Yount Prosper N. Boyaka Shan-Lu Liu Mark E. Peeples Amit Kapoor Jianrong Li 《Journal of virology》2021,95(20)
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We report a high-sensitivity cell secretome detection method using competitive immuno-aggregation and a micro-Coulter counter. A target cell secretome protein competes with anti-biotin-coated microparticles (MPs) to bind with a biotinylated antibody (Ab), causing decreased aggregation of the functionalized MPs and formation of a mixture of MPs and aggregates. In comparison, without the target cell secretome protein, more microparticles are functionalized, and more aggregates are formed. Thus, a decrease in the average volume of functionalized microparticles/aggregates indicates an increase in cell secretome concentration. This volume change is measured by the micro-Coulter counter, which is used to quantitatively estimate the cell secretome concentration. Vascular endothelial growth factor (VEGF), one of the key cell secretome proteins that regulate angiogenesis and vascular permeabilization, was used as the target protein to demonstrate the sensing principle. A standard calibration curve was generated by testing samples with various VEGF concentrations. A detection range from 0.01 ng/mL to 100.00 ng/mL was achieved. We further demonstrated the quantification of VEGF concentration in exogenous samples collected from the secretome of human mesenchymal stem cells (hMSCs) at different incubation times. The results from the assay agree well with the results of a parallel enzyme-linked immunoabsorbent assay (ELISA) test, indicating the specificity and reliability of the competitive immuno-aggregation assay. With its simple structure and easy sample preparation, this assay not only enables high sensitivity detection of VEGF but also can be readily extended to other types of cell secretome analysis as long as the specific Ab is known. 相似文献
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Wolfgang Lutz Samir KC 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2010,365(1554):2779-2791
The total size of the world population is likely to increase from its current 7 billion to 8–10 billion by 2050. This uncertainty is because of unknown future fertility and mortality trends in different parts of the world. But the young age structure of the population and the fact that in much of Africa and Western Asia, fertility is still very high makes an increase by at least one more billion almost certain. Virtually, all the increase will happen in the developing world. For the second half of the century, population stabilization and the onset of a decline are likely. In addition to the future size of the population, its distribution by age, sex, level of educational attainment and place of residence are of specific importance for studying future food security. The paper provides a detailed discussion of different relevant dimensions in population projections and an evaluation of the methods and assumptions used in current global population projections and in particular those produced by the United Nations and by IIASA. 相似文献
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Michaelidis Constantinos I.; Demary Kristian C.; Lewis Sara M. 《Behavioral ecology》2006,17(3):329-335
The evolutionary dynamic of courtship signaling systems is drivenby the interaction between male trait distributions and femalepreferences. This interaction is complex because females maychoose mates based on multiple components of male signals, andfemale preference functions may vary depending on mate availability,female reproductive state, and environmental conditions. InPhotinus fireflies (Coleoptera: Lampyridae), flying males emitbioluminescent flash signals to locate sedentary females, whichreply selectively to attractive male flash signals with theirown response flash. In this study, we first examined temporalvariation in the paired-pulse flash patterns produced by Photinusgreeni males in the field and found significant among-male variation(70% of total variation) in interpulse intervals (IPIs). Therewas no significant relationship between male IPI and spermatophoresize, suggesting that P. greeni male courtship signals do notprovide females with reliable indicators of male material resources.In laboratory playback experiments, we presented P. greeni femaleswith simulated flash signals to assess how IPI and pulse durationindependently affected the likelihood of female flash response.We also examined the effects of female body mass and time duringthe mating season on female preference functions, hypothesizingthat females would be less discriminating when they were heavier(more fecund) and when mate availability declined. We foundthat P. greeni females discriminated among signals within theirspecies' range based primarily on flash pattern IPI. Neitherthe time during the mating season nor female weight alteredfemale preference functions for IPI, although season did influencefemale response to pulse duration. These results reveal thatP. greeni females discriminate among conspecific males basedprimarily on male IPIs, the same signal character previouslyshown to be important for firefly species recognition. Fieldplayback experiments indicated that female responsiveness peakednear the average IPI given by males at different ambient temperatures,suggesting that fireflies exhibit temperature coupling similarto that seen in many acoustically signaling animals. 相似文献
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Listing J Strangfeld A Rau R Kekow J Gromnica-Ihle E Klopsch T Demary W Burmester GR Zink A 《Arthritis research & therapy》2006,8(3):R66
We investigated the frequency of remission according to the disease activity score (DAS28) definition, modified American Rheumatology Association (ARA) criteria, and the frequency of an achievement of a functional status above defined thresholds ('functional remission', 'physical independence') in rheumatoid arthritis (RA) patients treated with either biologics or conventional DMARDs. We used the data of a prospective cohort study, the German biologics register RABBIT (German acronym for Rheumatoid Arthritis--Observation of Biologic Therapy) to investigate the outcomes in RA patients with two or more DMARD failures who received new treatment with biologics (BIOL; n = 818) or a conventional DMARD (n = 265). Logistic regression analysis was applied to adjust for differences in baseline risks. Taking risk indicators such as previous DMARD failures or baseline clinical status into account, we found that biologics doubled the chance of remission compared to conventional DMARD therapies (DAS28 remission, adjusted odds ratio (OR) 1.95 (95% confidenece interval (CI) 1.2-3.2)); ARA remission, OR 2.05 (95% CI 1.2-3.5)). High remission rates (DAS28 remission, 30.6%; ARA remission, 16.9%) were observed in BIOL patients with a moderate disease activity (DAS28, 3.2 to 5.1) at the start of treatment. These rates decreased to 8.5% in patients with DAS28 > 6. Sustained remission at 6 and 12 months was achieved in <10% of the patients. Severely disabled patients (< or = 50% of full function) receiving biologic therapies were significantly more likely to achieve a status indicating physical independence (> or = 67% of full function) than controls (OR 3.88 (95% CI 1.7-8.8)). 'Functional remission' (> or = 83% of full function) was more often achieved in BIOL than in controls (OR 2.18 (95% CI 1.04-4.6)). In conclusion, our study shows that biologics increase the chance to achieve clinical remission and a status of functional remission or at least physical independence. However, temporary or even sustained remission remain ambitious aims, which are achieved in a minority of patients only. 相似文献
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Michael?B?Kupper Michael?Huhn Holger?Spiegel Julian?KC?Ma Stefan?Barth Rainer?Fischer Ricarda?FinnernEmail author 《BMC biotechnology》2005,5(1):4