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The principal legacy of Evans‐Pritchard's 1937 ethnography Witchcraft, oracles and magic among the Azande has been to associate debates over the rationality of witchcraft with its social categorization as a facet of misfortune and enmity. In combination with Evans‐Pritchard's own scepticism regarding witches, this allowed the rationality debate to isolate witchcraft as a distinctive special case. This logical exceptionalism was at odds with Evans‐Pritchard's own assertion of witchcraft's ordinariness, and is not supported by comparable ethnography from the Ladakh region of the Himalayas or by the unabridged versions of Oracles, both of which point towards an indigenous understanding of witchcraft as one variation on a spectrum of everyday action and craft. Instead, a revised reading of Oracles suggests that even the most basic quotidian representations of personal agency raise larger questions as to anthropology's understanding of how humans ascribe action and personhood, a debate which stands at the heart of its status as a science.  相似文献   

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Chlamydia pneumoniae is an obligate intracellular Gram‐negative bacterium with a unique biphasic developmental cycle that can cause persistent infections. In humans, Chlamydia causes airway infection and has been implicated in chronic inflammatory diseases, such as asthma and atherosclerosis. In addition, recent studies demonstrated that patients with severe periodontitis can harbor C. pneumoniae, which can increase the risk for a host inflammatory response with weighty clinical sequelae. Previous studies have established that periodontal pathogenic bacteria (i.e. Gram‐negative bacteria) can induce the synthesis and release of cytokines and other inflammatory mediators in human gingival fibroblasts. HGF are resident cells of the periodontium that respond to receptor stimulation by producing a variety of substances including cytokines and growth factors. Our results demonstrate that after 48 hr of incubation with viable C. pneumoniae HGF showed a proliferative response, as seen by both colorimetric MTT assay and direct cell count (30% and 35%, respectively). In addition, HGF incubated with viable or UV light‐inactivated C. pneumoniae organisms showed an increase in the levels of IL‐6 and IL‐10, but not IL‐4; on the contrary, HGF infected with heat‐killed bacteria did not show a significant production of any of the cytokines considered. In conclusion, the present study suggests that C. pneumoniae may modulate the expression of IL‐6 and IL‐10 by human gingival fibroblasts. Further studies are warranted to clarify the molecular mechanisms of C. pneumoniae in the regulation of cytokine expression by host cells and to elaborate the relevant clinical implications.  相似文献   

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Cystine‐knot peptides sharing a common fold but displaying a notably large diversity within the primary structure of flanking loops have shown great potential as scaffolds for the development of therapeutic and diagnostic agents. In this study, we demonstrated that the cystine‐knot peptide MCoTI‐II, a trypsin inhibitor from Momordica cochinchinensis, can be engineered to bind to cytotoxic T lymphocyte‐associated antigen 4 (CTLA‐4), an inhibitory receptor expressed by T lymphocytes, that has emerged as a target for the treatment of metastatic melanoma. Directed evolution was used to convert a cystine‐knot trypsin inhibitor into a CTLA‐4 binder by screening a library of variants using yeast surface display. A set of cystine‐knot peptides possessing dissociation constants in the micromolar range was obtained; the most potent variant was synthesized chemically. Successive conjugation with neutravidin, fusion to antibody Fc domain or the oligomerization domain of C4b binding protein resulted in oligovalent variants that possessed enhanced (up to 400‐fold) dissociation constants in the nanomolar range. Our data indicate that display of multiple knottin peptides on an oligomeric scaffold protein is a valid strategy to improve their functional affinity with ramifications for applications in diagnostics and therapy. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

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This article explores how people in the former Maoist heartland of Nepal adopted previously transgressive norms and practices during the decade of the People's War (1996‐2006). By examining the rise in practices of beef‐eating and inter‐caste commensality, this article suggests that the temporal dimension of wartime ‘when different rules apply’ was crucial in making people accept new ideas and break established norms on a scale atypical for the ‘normal’ times of peace. Analysing the agency of Maoist activists, who self‐consciously tried to implement a project of radical social transformation, and those people who were caught in the midst of the Maoist transformative endeavour, this article argues that the contours of the ‘new society’ emerged not only due to revolutionaries’ intentional actions but also because of the ‘exceptional’ nature of wartime, which forced people to radically re‐create their daily lives. By transgressing social norms, ‘ordinary’ people did not deliberately undermine the normative order, but rather responded to the constraints of wartime, when people's agency and ethical choices were mostly driven by the need to secure the survival of their families and ensure the continuity of life itself.  相似文献   

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We investigated the in vitro folding of an oxidized proinsulin (methionine‐arginine human lyspro‐proinsulin S‐sulfonate), using cysteine as a reducing agent at 5°C and high pH (10.5–11). Folding intermediates were detected and characterized by means of matrix‐assisted laser desorption ionization mass spectrometry (MALDI‐MS), reversed‐phase chromatography (RPC), size‐exclusion chromatography, and gel electrophoresis. The folding kinetics and yield depended on the protein and cysteine concentrations. RPC coupled with MALDI‐MS analyses indicated a sequential formation of intermediates with one, two, and three disulfide bonds. The MALDI‐MS analysis of Glu‐C digested, purified intermediates indicated that an intra‐A‐chain disulfide bond formed first among A6, A7, and A11. Various non‐native intra‐A (A20 with A6, A7, or A11), intra‐B (between B7 and B19), and inter‐A‐B disulfide bonds were observed in the intermediates with two disulfide bonds. The intermediates with three disulfide bonds had mainly the non‐native intra‐A and intra‐B bonds. At a cysteine‐to‐proinsulin‐SH ratio of 3.5, all intermediates with the non‐native disulfide bonds were converted to properly folded proinsulin via disulfide bond reshuffling, which was the slowest step. Aggregation via the formation of intermolecular disulfide bonds of early intermediates was the major cause of yield loss. At a higher cysteine‐to‐proinsulin‐SH ratio, some intermediates and folded MR‐KPB‐hPI were reduced to proteins with thiolate anions, which caused unfolding and even more yield loss than what resulted from aggregation of the early intermediates. Reducing protein concentration, while keeping an optimal cysteine‐to‐protein ratio, can improve folding yield significantly. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010  相似文献   

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Inflammation plays a major role in progression of rheumatoid arthritis, a disease treated with antagonists of tumor necrosis factor‐alpha (TNF‐α) and interleukin 1β (IL‐1β). New in vitro testing systems are needed to evaluate efficacies of new anti‐inflammatory biological drugs, ideally in a patient‐specific manner. To address this need, we studied microspheroids containing 10,000 human osteoarthritic primary chondrocytes (OACs) or chondrogenically differentiated mesenchymal stem cells (MSCs), obtained from three donors. Hypothesizing that this system can recapitulate clinically observed effects of anti‐inflammatory drugs, spheroids were exposed to TNF‐α, IL‐1β, or to supernatant containing secretome from activated macrophages (MCM). The anti‐inflammatory efficacies of anti‐TNF‐α biologicals adalimumab, infliximab, and etanercept, and the anti‐IL‐1β agent anakinra were assessed in short‐term microspheroid and long‐term macrospheroid cultures (100,000 OACs). While gene and protein expressions were evaluated in microspheroids, diameters, amounts of DNA, glycosaminoglycans, and hydroxiproline were measured in macrospheroids. The tested drugs significantly decreased the inflammation induced by TNF‐α or IL‐1β. The differences in potency of anti‐TNF‐α biologicals at 24 h and 3 weeks after their addition to inflamed spheroids were comparable, showing high predictability of short‐term cultures. Moreover, the data obtained with microspheroids grown from OACs and chondrogenically differentiated MSCs were comparable, suggesting that MSCs could be used for this type of in vitro testing. We propose that in vitro gene expression measured after the first 24 h in cultures of chondrogenically differentiated MSCs can be used to determine the functionality of anti‐TNF‐α drugs in personalized and preclinical studies. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1045–1058, 2018  相似文献   

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Previous studies have shown that the perceived times of voluntary actions and their effects are perceived as shifted towards each other, so that the interval between action and outcome seems shortened. This has been referred to as 'intentional binding' (IB). However, the generality of this effect remains unclear. Here we demonstrate that Intentional Binding also occurs in complex control situations. Using an aircraft supervision task with different autopilot settings, our results first indicated a strong relation between measures of IB and different levels of system automation. Second, measures of IB were related to explicit agency judgement in this applied setting. We discuss the implications for the underlying mechanisms, and for sense of agency in automated environments.  相似文献   

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Human mesenchymal stem cells (hMSCs) are colony‐forming unit fibroblasts (CFU‐F) derived from adult bone marrow and have significant potential for many cell‐based tissue‐engineering applications. Their therapeutic potential, however, is restricted by their diminishing plasticity as they are expanded in culture. In this study, we used N‐isopropylacrylamide (NIPAM)‐based thermoresponsive polyelectrolyte multilayer (N‐PEMU) films as culture substrates to support hMSC expansion and evaluated their effects on cell properties. The N‐PEMU films were made via layer‐by‐layer adsorption of thermoresponsive monomers copolymerized with charged monomers, positively charged allylamine hydrochloride (PAH), or negatively charged styrene sulfonic acid (PSS) and compared to fetal bovine serum (FBS) coated surfaces. Surface charges were shown to alter the extracellular matrix (ECM) structure and subsequently regulate hMSC responses including adhesion, proliferation, integrin expression, detachment, and colony forming ability. The positively charged thermal responsive surfaces improved cell adhesion and growth in a range comparable to control surfaces while maintaining significantly higher CFU‐F forming ability. Immunostaining and Western blot results indicate that the improved cell adhesion and growth on the positively charged surfaces resulted from the elevated adhesion of ECM proteins such as fibronectin on the positively charge surfaces. These results demonstrate that the layer‐by‐layer approach is an efficient way to form PNIPAM‐based thermal responsive surfaces for hMSC growth and removal without enzymatic treatment. The results also show that surface charge regulates ECM adhesion, which in turn influences not only cell adhesion but also CFU‐forming ability and their multi‐lineage differentiation potential. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010  相似文献   

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The landscape of human phosphorylation networks has not been systematically explored, representing vast, unchartered territories within cellular signaling networks. Although a large number of in vivo phosphorylated residues have been identified by mass spectrometry (MS)‐based approaches, assigning the upstream kinases to these residues requires biochemical analysis of kinase‐substrate relationships (KSRs). Here, we developed a new strategy, called CEASAR, based on functional protein microarrays and bioinformatics to experimentally identify substrates for 289 unique kinases, resulting in 3656 high‐quality KSRs. We then generated consensus phosphorylation motifs for each of the kinases and integrated this information, along with information about in vivo phosphorylation sites determined by MS, to construct a high‐resolution map of phosphorylation networks that connects 230 kinases to 2591 in vivo phosphorylation sites in 652 substrates. The value of this data set is demonstrated through the discovery of a new role for PKA downstream of Btk (Bruton's tyrosine kinase) during B‐cell receptor signaling. Overall, these studies provide global insights into kinase‐mediated signaling pathways and promise to advance our understanding of cellular signaling processes in humans.  相似文献   

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When humans wage war, it is not unusual for battlefields to be strewn with dead warriors. These warriors typically were men in their reproductive prime who, had they not died in battle, might have gone on to father more children. Typically, they are also genetically unrelated to one another. We know of no other animal species in which reproductively capable, genetically unrelated individuals risk their lives in this manner. Because the immense private costs borne by individual warriors create benefits that are shared widely by others in their group, warfare is a stark evolutionary puzzle that is difficult to explain. Although several scholars have posited models of the evolution of human warfare, 1 - 6 these models do not adequately explain how humans solve the problem of collective action in warfare at the evolutionarily novel scale of hundreds of genetically unrelated individuals. We propose that group‐structured cultural selection explains this phenomenon.  相似文献   

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Cationic lytic‐type peptides have been studied for clinical application in various infections and cancers, but their functional cellular mechanisms remain unclear. We generated anti‐cancer epithelial growth factor receptor (EGFR)‐lytic hybrid peptide, a 32‐amino‐acid peptide composed of an EGFR‐binding sequence and lytic sequence. In this study, we investigated the distribution of EGFR‐lytic hybrid peptide in BxPC‐3 human pancreatic cancer cells by an immunocytochemical (ICC) method. Distribution of EGFR protein expression was unchanged after treatment with EGFR‐lytic peptide compared with non‐treated cells. In confocal laser scanning microscopy, immunostaining of EGFR‐lytic peptide was observed in the cytoplasm, mostly in the form of granules. Some staining was also localized on the mitochondrial membrane. At the ultrastructure level, cells treated with EGFR‐lytic peptide had a low electron density, disappearance of microvilli, and swollen mitochondria. Fragments of cell membrane were also observed in the proximity of the membrane. In immunoelectron microscopy, EGFR‐lytic peptide was observed in the cell membrane and cytoplasm. A number of granules were considered swollen mitochondria. Activation of the caspase pathway as a result of mitochondrial dysfunction was also examined to determine the cytotoxic activity of EGFR‐lytic peptide; however, no effect on cell death after EGFR‐lytic treatment was observed, and moreover, apoptosis was not found to play a critical role in the cell death mechanism. These results suggest that EGFR‐lytic peptide is localized on cell and mitochondrial membranes, with disintegration of the cell membrane contributing mainly to cell death. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

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Butyrate‐producing bacteria play an important role in the human colon, supplying energy to the gut epithelium and regulating host cell responses. In order to explore the diversity and culturability of this functional group, we designed degenerate primers to amplify butyryl‐CoA:acetate CoA‐transferase sequences from faecal samples provided by 10 healthy volunteers. Eighty‐eight per cent of amplified sequences showed > 98% DNA sequence identity to CoA‐transferases from cultured butyrate‐producing bacteria, and these fell into 12 operational taxonomic units (OTUs). The four most prevalent OTUs corresponded to Eubacterium rectale, Roseburia faecis, Eubacterium hallii and an unnamed cultured species SS2/1. The remaining 12% of sequences, however, belonged to 20 OTUs that are assumed to come from uncultured butyrate‐producing strains. Samples taken after ingestion of inulin showed significant (P = 0.019) increases in Faecalibacterium prausnitzii. Because several of the dominant butyrate producers differ in their DNA % G+C content, analysis of thermal melt curves obtained for PCR amplicons of the butyryl‐CoA:acetate CoA‐transferase gene provides a convenient and rapid qualitative assessment of the major butyrate producing groups present in a given sample. This type of analysis therefore provides an excellent source of information on functionally important groups within the colonic microbial community.  相似文献   

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