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Mitochondrial DNA/protein complexes (nucleoids) appear as discrete entities inside the mitochondrial network when observed by live-cell imaging and immunofluorescence. This somewhat trivial observation in recent years has spurred research towards isolation of these complexes and the identification of nucleoid-associated proteins. Here we show that whole cell formaldehyde crosslinking combined with affinity purification and tandem mass-spectrometry provides a simple and reproducible method to identify potential nucleoid associated proteins. The method avoids spurious mitochondrial isolation and subsequent multifarious nucleoid enrichment protocols and can be implemented to allow for label-free quantification (LFQ) by mass-spectrometry. Using expression of a Flag-tagged Twinkle helicase and appropriate controls we show that this method identifies many previously identified nucleoid associated proteins. Using LFQ to compare HEK293 cells with and without mtDNA, but both expressing Twinkle-FLAG, identifies many proteins that are reduced or absent in the absence of mtDNA. This set not only includes established mtDNA maintenance proteins but also many proteins involved in mitochondrial RNA metabolism and translation and therefore represents what can be considered an mtDNA gene expression proteome. Our data provides a very valuable resource for both basic mitochondrial researchers as well as clinical geneticists working to identify novel disease genes on the basis of exome sequence data.  相似文献   
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Morphological traits of the ilium have consistently been more successful for juvenile sex determination than have techniques applied to other skeletal elements, however relatively little is known about the ontogeny and maturation of size and shape dimorphism in the ilium. We use a geometric morphometric approach to quantitatively separate the ontogeny of size and shape of the ilium, and analyze interpopulation differences in the onset, rate and patterning of sexual dimorphism. We captured the shape of three traits for a total of 191 ilia from Lisbon (Portugal) and London (UK) samples of known age and sex (0–17 years). Our results indicate that a) there is a clear dissociation between the ontogeny of size and shape in males and females, b) the ontogeny of size and shape are each defined by non‐linear trajectories that differ between the sexes, c) there are interpopulation differences in ontogenetic shape trajectories, which point to population‐specific patterning in the attainment of sexual dimorphism, and d) the rate of shape maturation and size maturation is typically higher for females than males. Male and female shape differences in the ilium are brought about by trajectory divergence. Differences in size and shape maturation between the sexes suggest that maturity may confound our ability to discriminate between the sexes by introducing variation not accounted for in age‐based groupings. The accuracy of sex determination methods using the ilium may be improved by the use of different traits for particular age groups, to capture the ontogenetic development of shape in both sexes. Am J Phys Anthropol 156:19–34, 2015 © 2014 Wiley Periodicals, Inc.  相似文献   
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The moccasin assemblage Julian Steward recovered from the Promontory caves in 1930–31 provides a novel example in which material culture can be used to understand the structure of an AD thirteenth century population. Several studies shed light on the relationship between shoe size, foot size, and stature. We develop an anthropometric model for understanding the composition of the Promontory Cave population by using moccasin size as a proxy for foot size. We then predict the stature of the individual who would have worn a moccasin. Stature is closely related to age for children, subadults and adult males. Although there are predictable sex and age factors biasing moccasin discard practices, moccasin dimensions suggest a relatively large proportion of children and subadults occupied the Promontory caves. This bison and antelope hunting population appears to have thrived during its stay on Promontory Point. Am J Phys Anthropol 156:76–89, 2015 © 2014 Wiley Periodicals, Inc.  相似文献   
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Amenity is a term that has re‐emerged within both public policy and environmental management organisations in response to an increasing emphasis on the human benefits derived from ecosystems. However, practical implementation of amenity management has been difficult due to a lack of definitional clarity within operational and academic literature. This article discusses the need for definitional clarity and understanding of the component elements of amenity that are integral to ecological management and reviews the literature on the perceptions and definitions of amenity in varied contexts. This study argues that positive perceptions of amenity benefits of a place are influenced by both physical elements such as sight, sound and smell and social elements such as age, education and cultural values. These elements should be considered by management agencies in a structured manner in order for the full potential of amenity to be realised. We present a conceptual framework to provide definitional clarity to the concept of amenity and highlight the interactions among its constituent elements. For the management of human‐dominated landscapes, considering the relationship between amenity and biodiversity may improve the integration of ecological and social goals.  相似文献   
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The objectives of this study were to characterise four essential oils (EO) chemically and to evaluate their effect on ruminal fermentation and methane emission in vitro. The investigated EO were isolated from Achillea santolina, Artemisia judaica, Schinus terebinthifolius and Mentha microphylla, and supplemented at four levels (0, 25, 50 and 75 microl) to 75 ml of buffered rumen fluid plus 0.5 g of substrate. The main components of the EO were piperitone (49.1%) and camphor (34.5%) in A. judaica, 16-dimethyl 15-cyclooactdaiene (60.5%) in A. santolina, piperitone oxide (46.7%) and cis-piperitone oxide (28%) in M. microphylla, and gamma-muurolene (45.3%) and alpha-thujene (16.0%) in S. terebinthifolius. The EO from A. santolina (at 25 and 50 j1), and all levels of A. judaica increased the gas production significantly, but S. terebinthifolius (at 50 and 75 microl), A. santolina (at 75 microl) and all levels of M. microphylla decreased the gas production significantly in comparison with the control. The highest levels of A. santolina and A. judaica, and all doses from M. microphylla EO inhibited the methane production along with a significant reduction in true degradation of dry matter and organic matter, protozoa count and NH3-N concentration. It is concluded that the evaluated EO have the potential to affect ruminal fermentation efficiency and the EO from M. microphylla could be a promising methane mitigating agent.  相似文献   
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Using laboratory experiments, simulation models, and analytical techniques, we examined the impact of dispersal on the mean densities of patchily distributed populations. Even when dispersal leads to no net additions or removals of individuals from a population, it may nonetheless increase mean population densities if the net immigration rate is positive when populations are growing and negative when they are declining. As a model system for exploring this phenomenon, we used the yeastlike fungus Aureobasidium pullulans. In a laboratory experiment, we showed that dispersal can both ensure persistence and increase mean population densities even when dispersal among populations causes no direct addition or loss of fungal cells. From the laboratory data, we constructed a plausible model of A. pullulans dynamics among apple leaves within an orchard. This simulation model demonstrated that the effect of dispersal on mean densities is enhanced by three factors: weak density dependence of the dynamics within populations, high environmental variability affecting population growth rates, and lack of synchrony among the fluctuations of populations. Using an analytical model, we showed that the underlying mechanisms for this phenomenon are general, suggesting that a large effect of dispersal on mean population densities is possible in many natural systems.  相似文献   
30.
Alpha-fetoprotein impairs APC function and induces their apoptosis   总被引:19,自引:0,他引:19  
alpha-Fetoprotein (AFP) is a tumor-associated Ag, and its serum level is elevated in patients with hepatocellular carcinoma (HCC). In vitro, AFP induces functional impairment of dendritic cells (DCs). This was demonstrated by the down-regulation of CD40 and CD86 molecules and the impairment of allostimulatory function. Also, AFP was found to induce significant apoptosis of DCs, and AFP-treated DCs produced low levels of IL-12 and TNF-alpha, a cytokine pattern that could hamper an efficient antitumor immune response. Ex vivo, APCs of patients with HCC and high levels of AFP produced lower levels of TNF-alpha than that of healthy individuals. In conclusion, these results illustrate that AFP induces dysfunction and apoptosis of APCs, thereby offering a mechanism by which HCC escapes immunological control.  相似文献   
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