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331.
Kraft RE 《Perspectives in biology and medicine》2012,55(2):201-217
Michigan's Appellate Court ruled in 2004 that a pregnancy that resulted from a rape should be considered a bodily injury for sentencing purposes. Interestingly, all three possible outcomes of a pregnancy-abortion, miscarriage, or childbirth-are considered to bring with them significant and substantial physical, psychological, and emotional changes. While the immediate impact of the ruling in People v. Cathey affected only the guilty individual, there are larger implications for this ruling beyond just sentencing guidelines. The ruling can be considered a step forward in prosecuting rapists, but possibly at the expense of reimagining the female body. This article considers the Cathey ruling itself, the potential benefits and consequences of this understanding on feminist discourse, and, crucially, the impact of this decision on abortion discussions. The central question that emerges is, can we both consider pregnancy a harm and believe that this harm is not always wrong-making? 相似文献
332.
333.
Ciesielski SJ Schilke BA Osipiuk J Bigelow L Mulligan R Majewska J Joachimiak A Marszalek J Craig EA Dutkiewicz R 《Journal of molecular biology》2012,417(1-2):1-12
The ubiquitous mitochondrial J-protein Jac1, called HscB in Escherichia coli, and its partner Hsp70 play a critical role in the transfer of Fe-S clusters from the scaffold protein Isu to recipient proteins. Biochemical results from eukaryotic and prokaryotic systems indicate that formation of the Jac1-Isu complex is important for both targeting of the Isu for Hsp70 binding and stimulation of Hsp70's ATPase activity. However, in apparent contradiction, we previously reported that an 8-fold decrease in Jac1's affinity for Isu1 is well tolerated in vivo, raising the question as to whether the Jac1:Isu interaction actually plays an important biological role. Here, we report the determination of the structure of Jac1 from Saccharomyces cerevisiae. Taking advantage of this information and recently published data from the homologous bacterial system, we determined that a total of eight surface-exposed residues play a role in Isu binding, as assessed by a set of biochemical assays. A variant having alanines substituted for these eight residues was unable to support growth of a jac1-Δ strain. However, replacement of three residues caused partial loss of function, resulting in a significant decrease in the Jac1:Isu1 interaction, a slow growth phenotype, and a reduction in the activity of Fe-S cluster-containing enzymes. Thus, we conclude that the Jac1:Isu1 interaction plays an indispensable role in the essential process of mitochondrial Fe-S cluster biogenesis. 相似文献
334.
AZ Worden J Janouskovec D McRose A Engman RM Welsh S Malfatti SG Tringe PJ Keeling 《Current biology : CB》2012,22(17):R675-R677
Eukaryotic phytoplankton play key roles in atmospheric CO(2) uptake and sequestration in marine environments [1,2]. Community shifts attributed to climate change have already been reported in the Arctic ocean, where tiny, photosynthetic picoeukaryotes (≤3 μm diameter) have increased, while larger taxa have decreased [3]. Unfortunately, for vast regions of the world's oceans, little is known about distributions of different genera and levels of genetic variation between ocean basins. This lack of baseline information makes it impossible to assess the impacts of environmental change on phytoplankton diversity, and global carbon cycling. A major knowledge impediment is that these organisms are highly diverse, and most remain uncultured [2]. Metagenomics avoids the culturing step and provides insights into genes present in the environment without some of the biases associated with conventional molecular survey methods. However, connecting metagenomic sequences to the organisms containing them is challenging. For many unicellular eukaryotes the reference genomes needed to make this connection are not available. We circumvented this problem using at-sea fluorescence activated cell sorting (FACS) to separate abundant natural populations of photosynthetic eukaryotes and sequence their DNA, generating reference genome information while eliminating the need for culturing [2]. Here, we present the complete chloroplast genome from an Atlantic picoeukaryote population and discoveries it enabled on the evolution, distribution, and potential carbon sequestration role of a tiny, wild alga. 相似文献
335.
Wilson RP Quintana F Hobson VJ 《Proceedings. Biological sciences / The Royal Society》2012,279(1730):975-980
Variation in the physical characteristics of the environment should impact the movement energetics of animals. Although cognizance of this may help interpret movement ecology, determination of the landscape-dependent energy expenditure of wild animals is problematic. We used accelerometers in animal-attached tags to derive energy expenditure in 54 free-living imperial cormorants Phalacrocorax atriceps and construct an energy landscape of the area around a breeding colony. Examination of the space use of a further 74 birds over 4 years showed that foraging areas selected varied considerably in distance from the colony and water depth, but were characterized by minimal power requirements compared with other areas in the available landscape. This accords with classic optimal foraging concepts, which state that animals should maximize net energy gain by minimizing costs where possible and show how deriving energy landscapes can help understand how and why animals distribute themselves in space. 相似文献
336.
The dorsal lateral geniculate nucleus (dLGN) serves as the primary conduit of retinal information to visual cortex. In addition to retinal input, dLGN receives a large feedback projection from layer VI of visual cortex. Such input modulates thalamic signal transmission in different ways that range from gain control to synchronizing network activity in a stimulus-specific manner. However, the mechanisms underlying such modulation have been difficult to study, in part because of the complex circuitry and diverse cell types this pathway innervates. To address this and overcome some of the technical limitations inherent in studying the corticothalamic (CT) pathway, we adopted a slice preparation in which we were able to stimulate CT terminal arbors in the visual thalamus of the mouse with blue light by using an adeno-associated virus to express the light-gated ion channel, ChIEF, in layer VI neurons. To examine the postsynaptic responses evoked by repetitive CT stimulation, we recorded from identified relay cells in dLGN, as well as GFP expressing GABAergic neurons in the thalamic reticular nucleus (TRN) and intrinsic interneurons of dLGN. Relay neurons exhibited large glutamatergic responses that continued to increase in amplitude with each successive stimulus pulse. While excitatory responses were apparent at postnatal day 10, the strong facilitation noted in adult was not observed until postnatal day 21. GABAergic neurons in TRN exhibited large initial excitatory responses that quickly plateaued during repetitive stimulation, indicating that the degree of facilitation was much larger for relay cells than for TRN neurons. The responses of intrinsic interneurons were smaller and took the form of a slow depolarization. These differences in the pattern of excitation for different thalamic cell types should help provide a framework for understanding how CT feedback alters the activity of visual thalamic circuitry during sensory processing as well as different behavioral or pathophysiological states. 相似文献
337.
Annelies W. Mesman Rory D. de Vries Stephen McQuaid W. Paul Duprex Rik L. de Swart Teunis B. H. Geijtenbeek 《PloS one》2012,7(12)
Measles virus (MV) is a highly contagious virus that is transmitted by aerosols. During systemic infection, CD150+ T and B lymphocytes in blood and lymphoid tissues are the main cells infected by pathogenic MV. However, it is unclear which cell types are the primary targets for MV in the lungs and how the virus reaches the lymphoid tissues. In vitro studies have shown that dendritic cell (DC) C-type lectin DC-SIGN captures MV, leading to infection of DCs as well as transmission to lymphocytes. However, evidence of DC-SIGN-mediated transmission in vivo has not been established. Here we identified DC-SIGNhi DCs as first target cells in vivo and demonstrate that macaque DC-SIGN functions as an attachment receptor for MV. Notably, DC-SIGNhi cells from macaque broncho-alveolar lavage and lymph nodes transmit MV to B lymphocytes, providing in vivo support for an important role for DCs in both initiation and dissemination of MV infection. 相似文献
338.
Fen Z. Hu Rory Eutsey Azad Ahmed Nelson Frazao Evan Powell N. Luisa Hiller Todd Hillman Farrel J. Buchinsky Robert Boissy Benjamin Janto Jennifer Kress-Bennett Mark Longwell Suzanne Ezzo J. Christopher Post Mirjana Nesin Alexander Tomasz Garth D. Ehrlich 《PloS one》2012,7(11)
Two multidrug resistant strains of Streptococcus pneumoniae – SV35-T23 (capsular type 23F) and SV36-T3 (capsular type 3) were recovered from the nasopharynx of two adult patients during an outbreak of pneumococcal disease in a New York hospital in 1996. Both strains belonged to the pandemic lineage PMEN1 but they differed strikingly in virulence when tested in the mouse model of IP infection: as few as 1000 CFU of SV36 killed all mice within 24 hours after inoculation while SV35-T23 was avirulent.Whole genome sequencing (WGS) of the two isolates was performed (i) to test if these two isolates belonging to the same clonal type and recovered from an identical epidemiological scenario only differed in their capsular genes? and (ii) to test if the vast difference in virulence between the strains was mostly – or exclusively – due to the type III capsule. WGS demonstrated extensive differences between the two isolates including over 2500 single nucleotide polymorphisms in core genes and also differences in 36 genetic determinants: 25 of which were unique to SV35-T23 and 11 unique to strain SV36-T3. Nineteen of these differences were capsular genes and 9 bacteriocin genes.Using genetic transformation in the laboratory, the capsular region of SV35-T23 was replaced by the type 3 capsular genes from SV36-T3 to generate the recombinant SV35-T3* which was as virulent as the parental strain SV36-T3* in the murine model and the type 3 capsule was the major virulence factor in the chinchilla model as well. On the other hand, a careful comparison of strains SV36-T3 and the laboratory constructed SV35-T3* in the chinchilla model suggested that some additional determinants present in SV36 but not in the laboratory recombinant may also contribute to the progression of middle ear disease. The nature of this determinants remains to be identified. 相似文献
339.
Ahmed A Earl J Retchless A Hillier SL Rabe LK Cherpes TL Powell E Janto B Eutsey R Hiller NL Boissy R Dahlgren ME Hall BG Costerton JW Post JC Hu FZ Ehrlich GD 《Journal of bacteriology》2012,194(15):3922-3937
Gardnerella vaginalis is associated with a spectrum of clinical conditions, suggesting high degrees of genetic heterogeneity among stains. Seventeen G. vaginalis isolates were subjected to a battery of comparative genomic analyses to determine their level of relatedness. For each measure, the degree of difference among the G. vaginalis strains was the highest observed among 23 pathogenic bacterial species for which at least eight genomes are available. Genome sizes ranged from 1.491 to 1.716 Mb; GC contents ranged from 41.18% to 43.40%; and the core genome, consisting of only 746 genes, makes up only 51.6% of each strain's genome on average and accounts for only 27% of the species supragenome. Neighbor-grouping analyses, using both distributed gene possession data and core gene allelic data, each identified two major sets of strains, each of which is composed of two groups. Each of the four groups has its own characteristic genome size, GC ratio, and greatly expanded core gene content, making the genomic diversity of each group within the range for other bacterial species. To test whether these 4 groups corresponded to genetically isolated clades, we inferred the phylogeny of each distributed gene that was present in at least two strains and absent in at least two strains; this analysis identified frequent homologous recombination within groups but not between groups or sets. G. vaginalis appears to include four nonrecombining groups/clades of organisms with distinct gene pools and genomic properties, which may confer distinct ecological properties. Consequently, it may be appropriate to treat these four groups as separate species. 相似文献
340.
Christopher D. Williams James Moran Owen Doherty Rory J. Mc Donnell Michael J. Gormally Lloyd V. Knutson Jean-Claude Vala 《Aquatic Ecology》2009,43(1):117-133
Sciomyzid flies, which have potential as bio-indicators, were sampled by sweep-net surveys at a turlough in the west of Ireland.
Turloughs are ephemeral wetlands (unique to Ireland), which flood from groundwater in winter and empty in the summer, during
that time, they are frequently grazed. The weekly survey consisted of ten linear sweeps (5 m × 1 m) in each of six homogeneous
and contiguous vegetation zones throughout the summer of 2004. The fauna was dominated by univoltine species with Ilione albiseta being particularly abundant, though species displaying a range of phenologies and life histories were also present. Species
richness and total abundance were significantly higher in the two zones with the highest hydroperiods. Mantel tests showed
that the species matrix was significantly co-structured with permanent features of the physical environment, but not with
stochastic sampling variables related to weather conditions. Mantel correllograms displayed typical patterns of autocorrelation
for hydroperiod, soil moisture and soil pH in each zone and vegetation height, vegetation length and Ellenberg moisture index
(weighted for vegetation composition) in each sweep-path. No patterns of autocorrelation were evident for distance among zones,
area of patch of vegetation zone sampled, area of the vegetation zone on the whole turlough, soil mass-loss-on-ignition and
Ellenberg N and reaction indices. These results provide strong evidence for high microhabitat specificity in Sciomyzidae at
this site and indicate a major influence of vegetation structure and hydrological regime on their ecology.
相似文献
Jean-Claude ValaEmail: |