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951.
Genetic and molecular analysis of the Enhancer (En) transposable element system of Zea mays 总被引:8,自引:7,他引:8
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Pereira A Schwarz-Sommer Z Gierl A Bertram I Peterson PA Saedler H 《The EMBO journal》1985,4(1):17-23
A newly isolated, unstable mutation wx-844::En-1 of Zea mays was proven to be caused by the insertion of the autonomous transposable element En into the Waxy (Wx) gene. Molecular analysis revealed that En-1 is 8.4 kb long, has a 13-bp long perfect inverted repeat at its termini and generates a 3-bp target site duplication. En-1 is integrated into an intron located approximately in the middle of the transcribed region of the Wx gene. Structural evidence is presented indicating that a receptor component (Inhibitor) can arise by internal deletion of an autonomous En element. 相似文献
952.
Daniel S. La Emily A. Peterson Christiane Bode Alessandro A. Boezio Howard Bregman Margaret Y. Chu-Moyer James Coats Erin F. DiMauro Thomas A. Dineen Bingfan Du Hua Gao Russell Graceffa Hakan Gunaydin Angel Guzman-Perez Robert Fremeau Xin Huang Christopher Ilch Thomas J. Kornecook Matthew M. Weiss 《Bioorganic & medicinal chemistry letters》2017,27(15):3477-3485
The voltage-gated sodium channel NaV1.7 has received much attention from the scientific community due to compelling human genetic data linking gain- and loss-of-function mutations to pain phenotypes. Despite this genetic validation of NaV1.7 as a target for pain, high quality pharmacological tools facilitate further understanding of target biology, establishment of target coverage requirements and subsequent progression into the clinic. Within the sulfonamide class of inhibitors, reduced potency on rat NaV1.7 versus human NaV1.7 was observed, rendering in vivo rat pharmacology studies challenging. Herein, we report the discovery and optimization of novel benzoxazine sulfonamide inhibitors of human, rat and mouse NaV1.7 which enabled pharmacological assessment in traditional behavioral rodent models of pain and in turn, established a connection between formalin-induced pain and histamine-induced pruritus in mice. The latter represents a simple and efficient means of measuring target engagement. 相似文献
953.
Magnus Lovén Wallerius Joacim Näslund Barbara Koeck Jörgen I. Johnsson 《Ethology : formerly Zeitschrift fur Tierpsychologie》2017,123(12):933-941
The introduction of non‐native brook trout (Salvelinus fontinalis) in Europe has led to displacement and decreasing populations of native brown trout (Salmo trutta). Some studies have found that brown trout shift to a diet niche similar to brook trout when the two species live in sympatry, which conflicts with the competitive exclusion principle. A change in feeding niche may be a sign of early interspecific association and social learning, leading to behavioral changes. As a first step to address this possibility, it is essential to assess the interspecific association between the species during the early ontogenetic life stages. In this study, we therefore assess whether juvenile brown trout associate with non‐native juvenile brook trout to the same extent as with conspecifics by setting up two experiments: (i) a binomial choice test allowing visual and chemical cues to estimate the species specificity of group preference, and (ii) an association test without physical barriers to estimate the degree of association of a focal brown trout with a group of either conspecifics or heterospecifics. In experiment (1), we found that focal juvenile brown trout preferred to associate with the stimuli groups and did not discriminate either against conspecific or heterospecific groups. Furthermore, more active individuals showed stronger preference for the stimuli group than less active ones, regardless of species. In experiment (2), we found that brook trout groups had a tighter group structure than brown trout groups, and that focal brown trout showed stronger association with brook trout than with brown trout. These results indicate that brown trout may associate with brook trout at an early life stage, which would allow for interspecific social learning to occur. Future studies should look closer into causes and consequences of interspecific association and social learning, including potential effects on the phenotype selection in brown trout populations. 相似文献
954.
955.
Magnus Fiskesjö 《Anthropological Forum》2017,27(4):340-364
ABSTRACTThe Wa spirit world implies a certain rootedness. Knowledge of the location and propensities of spirits is necessary to engage their capricious menace through divination diagnostics and sacrificial remedies. Even as outsiders have attempted to introduce modern medicine, spirit neighbours and enemies continue to figure prominently in Wa health, disease and death. I outline how these practices for managing the menaces of the spirit world survived the demise of the political autonomy of the Wa in the 1950s and 1960s, when the ancient Wa lands were divided and annexed by the nation-states of China and Burma. Finally, I discuss the disastrous consequences of recent forced displacements of large numbers of people, which caused many unnecessary deaths by disrupted the victim’s established ways of dealing with disease as anchored in the local landscape. 相似文献
956.
Survey data on people’s reported attitudes towards ethnic minorities are sometimes used as a proxy for ethnic discrimination. However, there is weak empirical evidence of a link between reported attitudes and discrimination. In this article, we use survey data on people’s attitudes towards ethnic minorities combined with a direct measure of ethnic discrimination from a field experiment in the Swedish housing market to re-examine this policy-relevant issue. We find clear evidence of a link between reported attitudes towards ethnic minorities and the extent of ethnic discrimination: in regions where attitudes are more negative, there is more discrimination, and vice versa. Thus, in contrast to most prior studies, our results suggest that reported attitudes may be a useful predictor of ethnic discrimination. 相似文献
957.
Marie Krogh Nielsen Sven Magnus Hector Kelly Allen Yousif Subhi Torben Lykke Sørensen 《Immunity & ageing : I & A》2017,14(1):18
Background
Neutrophil dysfunction plays a key role in the development of diseases characterized by inflammation and angiogenesis. Here, we studied the systemic expression of neutrophil markers reflecting activation, adhesion, and resolution of inflammation in patients with neovascular age-related macular degeneration (AMD).Results
This was a prospective case-control study of patients with neovascular AMD and age-matched healthy control individuals. Patients were recruited from an outpatient program, and control individuals were recruited amongst patients’ relatives. Current smokers and individuals with either active immune-disease or ongoing cancer were not included, as these factors are known to affect neutrophil function. Fresh-drawn venous blood was processed for flow cytometric analysis of neutrophil markers. We determined percentages of positive cells and compared expression levels using fluorescence intensity measures. We found conditional differences on marker expression between patients with neovascular AMD (n = 29) and controls (n = 28): no differences were found when looking broadly, but several differences emerged when focusing on non-smokers. Here, patients with neovascular AMD had increased expression of the activity marker cluster of differentiation (CD) 66b (P = 0.003; Mann-Whitney U test), decreased expression of adhesion marker CD162 (P = 0.044; Mann-Whitney U test), and lower expression of the resolution of inflammation marker C-X-C chemokine receptor 2 (P = 0.044; Mann-Whitney U test).Conclusions
We present novel evidence suggesting that the activity of circulating neutrophils, sensitive to smoking, may differ in patients with neovascular AMD.958.
Anna C. Peterson Bruno M. Ghersi Fernando Alda Cadhla Firth Matthew J. Frye Ying Bai Lynn M. Osikowicz Claudia Riegel W. Ian Lipkin Michael Y. Kosoy Michael J. Blum 《EcoHealth》2017,14(4):771-782
It is becoming increasingly likely that rodents will drive future disease epidemics with the continued expansion of cities worldwide. Though transmission risk is a growing concern, relatively little is known about pathogens carried by urban rats. Here, we assess whether the diversity and prevalence of Bartonella bacteria differ according to the (co)occurrence of rat hosts across New Orleans, LA (NO), where both Norway (Rattus norvegicus) and roof rats (Rattus rattus) are found, relative to New York City (NYC) which only harbors Norway rats. We detected human pathogenic Bartonella species in both NYC and New Orleans rodents. We found that Norway rats in New Orleans harbored a more diverse assemblage of Bartonella than Norway rats in NYC and that Norway rats harbored a more diverse and distinct assemblage of Bartonella compared to roof rats in New Orleans. Additionally, Norway rats were more likely to be infected with Bartonella than roof rats in New Orleans. Flea infestation appears to be an important predictor of Bartonella infection in Norway rats across both cities. These findings illustrate that pathogen infections can be heterogeneous in urban rodents and indicate that further study of host species interactions could clarify variation in spillover risk across cities. 相似文献
959.
960.