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91.
Invasive alien species are a major threat to biodiversity and human activities, providing a strong incentive to understand the processes by which alien invasion occurs. While it is important to understand the determinants of success at each of several invasion stages—transport, introduction, establishment, and spread—few studies have explored the first of these stages. Here, we quantify and analyze variation in the success of individual animals in surviving the transport stage, based on shipping records of European passerines destined for New Zealand. We mined the original documents of Acclimatisation Societies, established in New Zealand for the purpose of introducing supposedly beneficial alien species, in combination with recently digitized newspaper archives, to produce a unique dataset of 122 ships that carried passerines from Europe to New Zealand between 1850 and 1885. For 37 of these shipments, data on the survival of individual species were available. Using generalized linear mixed models, we explored how survival was related to characteristics of the shipments and the species. We show that species differed greatly in their survival, but none of the tested traits accounted for these differences. Yet, survival increased over time, which mirrors the switch from early haphazard shipments to larger organized shipments. Our results imply that it was the quality of care received by the birds that most affected success at this stage of the invasion process.  相似文献   
92.
We performed exome sequencing for mutation discovery of an ENU (N-ethyl-N-nitrosourea)-derived mouse model characterized by significant elevated plasma alkaline phosphatase (ALP) activities in female and male mutant mice, originally named BAP014 (bone screen alkaline phosphatase #14). We identified a novel loss-of-function mutation within the Fam46a (family with sequence similarity 46, member A) gene (NM_001160378.1:c.469G>T, NP_001153850.1:p.Glu157*). Heterozygous mice of this mouse line (renamed Fam46a E157*Mhda) had significantly high ALP activities and apparently no other differences in morphology compared to wild-type mice. In contrast, homozygous Fam46a E157*Mhda mice showed severe morphological and skeletal abnormalities including short stature along with limb, rib, pelvis, and skull deformities with minimal trabecular bone and reduced cortical bone thickness in long bones. ALP activities of homozygous mutants were almost two-fold higher than in heterozygous mice. Fam46a is weakly expressed in most adult and embryonic tissues with a strong expression in mineralized tissues as calvaria and femur. The FAM46A protein is computationally predicted as a new member of the superfamily of nucleotidyltransferase fold proteins, but little is known about its function. Fam46a E157*Mhda mice are the first mouse model for a mutation within the Fam46a gene.  相似文献   
93.
A highly stable and sensitive amperometric alcohol biosensor was developed by immobilizing alcohol oxidase (AOX) through Polyamidoamine (PAMAM) dendrimers on a cysteamine‐modified gold electrode surface. Ethanol determination is based on the consumption of dissolved oxygen content due to the enzymatic reaction. The decrease in oxygen level was monitored at ?0.7 V vs. Ag/AgCl and correlated with ethanol concentration. Optimization of variables affecting the system was performed. The optimized ethanol biosensor showed a wide linearity from 0.025 to 1.0 mM with 100 s response time and detection limit of (LOD) 0.016 mM. In the characterization studies, besides linearity some parameters such as operational and storage stability, reproducibility, repeatability, and substrate specificity were studied in detail. Stability studies showed a good preservation of the bioanalytical properties of the sensor, 67% of its initial sensitivity was kept after 1 month storage at 4°C. The analytical characteristics of the system were also evaluated for alcohol determination in flow injection analysis (FIA) mode. Finally, proposed biosensor was applied for ethanol analysis in various alcoholic beverage as well as offline monitoring of alcohol production through the yeast cultivation. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010  相似文献   
94.
The Acanthocephala is a phylum of obligate endoparasitic animals comprising four classes (Archiacanthocephala, Palaeacanthocephala, Eoacanthocephala and Polyacanthocephala), although the phylogenetic interrelationships of these classes still remains unresolved. To investigate phylogenetic relationships of major acanthocephalan groups, we characterized the complete mitochondrial genome sequences of two palaeacanthocephalan species Centrorhynchus aluconis and Prosthorhynchus transversus (representing two different families of the order Polymorphida), and Polyacanthorhynchus caballeroi (the first mitogenomic representative of the class Polyacanthocephala) and used these new sequences for phylogenetic analyses, along with 32 platyzoan mtDNAs, including 10 additional acanthocephalans. Phylogenetic analyses using concatenated amino acid sequences for 12 protein‐coding genes with maximum likelihood and Bayesian inference methods supported monophyly of Acanthocephala. Within the phylum, Archiacanthocephala was positioned as the sister to the clade containing all three other acanthocephalan classes, with the polyacanthocephalan species P. caballeroi nested within Eoacanthocephala. This result contradicts morphology‐based classification systems that treated polyacanthorhynchids as one of the palaeacanthocephalan families, and instead suggests Polyacanthocephala is a member of Eoacanthocephala. Within the Palaeacanthocephala, Polymorphida monophyly was strongly supported and this is inconsistent with nuclear rDNA‐based molecular hypotheses that suggest non‐monophyly.  相似文献   
95.
Previous studies have identified two tissue- and cell-specific, yet functionally redundant, sucrose synthase (SuSy) genes, Sh1 and Sus1, which encode biochemically similar isozymes, SH1 and SUS1 (previously referred to as SS1 and SS2, respectively). Here we report evidence for a third SuSy gene in maize, Sus3, which is more similar to dicot than to monocot SuSys. RNA and/or protein blot analyses on developing kernels and other tissues show evidence of expression of Sus3, although at the lowest steady-state levels of the three SuSy gene products and without a unique pattern of tissue specificity. Immunoblots of sh1sus1-1 embryos that are either lacking or deficient for the embryo-specific SUS1 protein have shown a protein band which we attribute to the Sus3 gene, and may contribute to the residual enzyme activity seen in embryos of the double mutant. We also studied developing seeds of the double mutant sh1sus1-1, which is missing 99.5% of SuSy enzyme activity, for evidence of co-regulation of several genes of sugar metabolism. We found a significant reduction in the steady-state levels of Miniature-1 encoded cell wall invertase2, and Sucrose transporter (Sut) mRNAs in the double mutant, relative to the lineage-related sh1Sus1 and sh1Sus1 kernels. Down-regulation of the Mn1 gene was also reflected in significant reductions in cell wall invertase activity. Co-regulatory changes were not seen in the expression of Sucrose phosphate synthase, UDP-glucose pyrophosphorylase, and ADP-glucose pyrophosphorylase.  相似文献   
96.
BackgroundCirculating cell-free fetal DNA has enabled non-invasive prenatal fetal aneuploidy testing without direct discrimination of the maternal and fetal DNA. Testing may be improved by specifically enriching the sample material for fetal DNA. DNA methylation may allow for such a separation of DNA; however, this depends on knowledge of the methylomes of circulating cell-free DNA and its cellular contributors.ResultsWe perform whole genome bisulfite sequencing on a set of unmatched samples including circulating cell-free DNA from non-pregnant and pregnant female donors and genomic DNA from maternal buffy coat and placenta samples. We find CpG cytosines within longer fragments are more likely to be methylated. Comparison of the methylomes of placenta and non-pregnant circulating cell-free DNA reveal many of the 51,259 identified differentially methylated regions are located in domains exhibiting consistent placenta hypomethylation across millions of consecutive bases. We find these placenta hypomethylated domains are consistently located within regions exhibiting low CpG and gene density. Differentially methylated regions identified when comparing placenta to non-pregnant circulating cell-free DNA are recapitulated in pregnant circulating cell-free DNA, confirming the ability to detect differential methylation in circulating cell-free DNA mixtures.ConclusionsWe generate methylome maps for four sample types at single-base resolution, identify a link between DNA methylation and fragment length in circulating cell-free DNA, identify differentially methylated regions between sample groups, and uncover the presence of megabase-size placenta hypomethylated domains.

Electronic supplementary material

The online version of this article (doi:10.1186/s13059-015-0645-x) contains supplementary material, which is available to authorized users.  相似文献   
97.
Deserts are particularly vulnerable to human impacts and have already suffered a substantial loss of biodiversity. In harsh and variable desert environments, large herbivores typically occur at low densities, and their large carnivore predators occur at even lower densities. The continued survival of large carnivores is key to healthy functioning desert ecosystems, and the ability to gather reliable information on these rare low density species, including presence, abundance and density, is critical to their monitoring and management. Here we test camera trap methodologies as a monitoring tool for an extremely rare wide-ranging large felid, the critically endangered Saharan cheetah (Acinonyx jubatus hecki). Two camera trapping surveys were carried out over 2–3 months across a 2,551km2 grid in the Ti-n-hağğen region in the Ahaggar Cultural Park, south central Algeria. A total of 32 records of Saharan cheetah were obtained. We show the behaviour and ecology of the Saharan cheetah is severely constrained by the harsh desert environment, leading them to be more nocturnal, be more wide-ranging, and occur at lower densities relative to cheetah in savannah environments. Density estimates ranged from 0.21–0.55/1,000km2, some of the lowest large carnivore densities ever recorded in Africa, and average home range size over 2–3 months was estimated at 1,583km2. We use our results to predict that, in order to detect presence of cheetah with p>0.95 a survey effort of at least 1,000 camera trap days is required. Our study identifies the Ahaggar Cultural Park as a key area for the conservation of the Saharan cheetah. The Saharan cheetah meets the requirements for a charismatic flagship species that can be used to “market” the Saharan landscape at a sufficiently large scale to help reverse the historical neglect of threatened Saharan ecosystems.  相似文献   
98.
Personalized medicine allows the selection of treatments best suited to an individual patient and disease phenotype. To implement personalized medicine, effective tests predictive of response to treatment or susceptibility to adverse events are needed, and to develop a personalized medicine test, both high quality samples and reliable data are required. We review key features of state-of-the-art proteomic profiling and introduce further analytic developments to build a proteomic toolkit for use in personalized medicine approaches. The combination of novel analytical approaches in proteomic data generation, alignment and comparison permit translation of identified biomarkers into practical assays. We further propose an expanded statistical analysis to understand the sources of variability between individuals in terms of both protein expression and clinical variables and utilize this understanding in a predictive test.  相似文献   
99.
Although nitric oxide (NO) is important for cell signaling and nonspecific immunity in the fruit fly Drosophila melanogaster, little is known about its single NO synthase (dNOS). We expressed the oxygenase domain of dNOS (dNOSoxy), characterized its spectroscopic, kinetic, and catalytic properties, and interpreted them in light of a global kinetic model for NO synthesis. Single turnover reactions with ferrous dNOSoxy showed it could convert Arg to N'omega-hydroxy-l-arginine (NOHA), or NOHA to citrulline and NO, when it was given 6R-tetrahydrobiopterin and O2. The dNOSoxy catalyzed Arg hydroxylation and NOHA oxidation at rates that matched or exceeded the rates catalyzed by the three mammalian NOSoxy enzymes. Consecutive heme-dioxy, ferric heme-NO, and ferric heme species were observed in the NOHA reaction of dNOSoxy, indicating that its catalytic mechanism is the same as in the mammalian NOS. However, NO dissociation from dNOSoxy was 4 to 9 times faster than that from the mammalian NOS enzymes. In contrast, the dNOSoxy ferrous heme-NO complex was relatively unreactive toward O2 and in this way was equivalent to the mammalian neuronal NOS. Our data show that dNOSoxy has unique settings for the kinetic parameters that determine its NO synthesis. Computer simulations reveal that these unique settings should enable dNOS to be a more efficient and active NO synthase than the mammalian NOS enzymes, which may allow it to function more broadly in cell signaling and immune functions in the fruit fly.  相似文献   
100.
Cleft lip and palate is the most common of the congenital conditions affecting the face and cranial bones and is associated with a raised risk of difficulties in infant-caregiver interaction; the reasons for such difficulties are not fully understood. Here, we report two experiments designed to explore how adults respond to infant faces with and without cleft lip, using behavioural measures of attractiveness appraisal ('liking') and willingness to work to view or remove the images ('wanting'). We found that infants with cleft lip were rated as less attractive and were viewed for shorter durations than healthy infants, an effect that was particularly apparent where the cleft lip was severe. Women rated the infant faces as more attractive than men did, but there were no differences in men and women's viewing times of these faces. In a second experiment, we found that the presence of a cleft lip in domestic animals affected adults' 'liking' and 'wanting' responses in a comparable way to that seen for human infants. Adults' responses were also remarkably similar for images of infants and animals with cleft lip, although no gender difference in attractiveness ratings or viewing times emerged for animals. We suggest that the presence of a cleft lip can substantially change the way in which adults respond to human and animal faces. Furthermore, women may respond in different ways to men when asked to appraise infant attractiveness, despite the fact that men and women 'want' to view images of infants for similar durations.  相似文献   
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