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51.
The backbone and side chain resonance assignments of an engineered intein based on Mycobacterium tuberculosis RecA have been determined based on triple-resonance experiments with the uniformly [13C,15N]-labeled protein.  相似文献   
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Background

Antibodies that inhibit the growth of blood-stage Plasmodium falciparum may play an important role in acquired and vaccine-induced immunity in humans. However, the acquisition and activity of these antibodies is not well understood.

Methods

We tested dialysed serum and purified immunoglobulins from Kenyan children and adults for inhibition of P. falciparum blood-stage growth in vitro using different parasite lines. Serum antibodies were measured by ELISA to blood-stage parasite antigens, extracted from P. falciparum schizonts, and to recombinant merozoite surface protein 1 (42 kDa C-terminal fragment, MSP1-42).

Results

Antibodies to blood-stage antigens present in schizont protein extract and to recombinant MSP1-42 significantly increased with age and were highly correlated. In contrast, growth-inhibitory activity was not strongly associated with age and tended to decline marginally with increasing age and exposure, with young children demonstrating the highest inhibitory activity. Comparison of growth-inhibitory activity among samples collected from the same population at different time points suggested that malaria transmission intensity influenced the level of growth-inhibitory antibodies. Antibodies to recombinant MSP1-42 were not associated with growth inhibition and high immunoglobulin G levels were poorly predictive of inhibitory activity. The level of inhibitory activity against different isolates varied.

Conclusions

Children can acquire growth-inhibitory antibodies at a young age, but once they are acquired they do not appear to be boosted by on-going exposure. Inhibitory antibodies may play a role in protection from early childhood malaria.  相似文献   
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The article reconsiders the concept of ecumene in anthropology, through a focus on Panoan-language-speaking indigenous peoples in Brazil. It explores the notion that ecumenes are intersubjectively forged space-times and it critiques culturalist and evolutionist approaches to the ecumene concept. Drawing on ethnography of Yawanawá and Cashinahua, analysis treats ecumenes as dynamic space-times within which amity and enmity arise and identity politics are forged or falter. These arise phenomenologically over time as bodies acquire knowledge, capacity, creativity, and agency, resulting in the sedimentation and fixation of humanness, seen as contingent and temporary in nature. It is argued that if ecumene is to be a useful category of analysis, it is necessary to put aside heuristic divisions between indigenous and anthropological conceptual and theoretical framing of global historical processes. Ecumene needs be framed with respect to an analysis of graduated sovereignty, predatory capitalism, and institutionalized racism, as Amerindians experience and frame these historically.  相似文献   
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Changes in cell macromolecular composition during different phases of growth correlated with alterations in morphology of the obligately anaerobic bacterium, Bacteroides fragilis, grown in a complex medium.  相似文献   
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Raspberry volatiles are important for perceptions of sensory quality, mould resistance and some have nutraceutical activities. Twelve raspberry character volatiles were quantified, 11 of them in fruit from two seasons, from plants from the Glen Moy × Latham mapping population growing in both open field and under cover (polytunnels). Effects of season and environment were examined for their impact on the content of α-ionone, α-ionol, β-ionone, β-damascenone, linalool, geraniol, benzyl alcohol, (Z)-3-hexenol, acetoin, acetic and hexanoic acids, whilst raspberry ketone was measured in one season. A significant variation was observed in fruit volatiles in all progeny between seasons and method of cultivation. Quantitative trait loci were determined and mapped to six of the seven linkage groups, as were candidate genes in the volatiles pathways.  相似文献   
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