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101.
According to one influential account, face processing atypicalities in autism reflect reduced reward value of faces, which results in limited attention to faces during development and a consequent failure to acquire face expertise. Surprisingly, however, there is a paucity of work directly investigating the reward value of faces for individuals with autism and the evidence for diminished face rewards in this population remains equivocal. In the current study, we measured how hard children with autism would work to view faces, using an effortful key-press sequence, and whether they were sensitive to the differential reward value of attractive and unattractive faces. Contrary to expectations, cognitively able children with autism did not differ from typically developing children of similar age and ability in their willingness to work to view faces. Moreover, the effort expended was strongly positively correlated with facial attractiveness ratings in both groups of children. There was also no evidence of atypical reward values for other, less social categories (cars and inverted faces) in the children with autism. These results speak against the possibility that face recognition difficulties in autism are explained by atypical reward value of faces.  相似文献   
102.

Petroleum pollution is a major concern in Antarctica due to the persistent nature of its hydrocarbon components coupled with the region’s extreme environmental conditions, which means that bioremediation approaches are largely inapplicable at present. The current study assessed the ability of the psychrotolerant phenol-degrader, Rhodococcus sp. strain AQ5-07, to assimilate diesel fuel as the sole carbon source. Factors expected to influence the efficiency of diesel degradation, including the initial hydrocarbon concentration, nitrogen source concentration and type, temperature, pH and salinity were studied. Strain AQ5-07 displayed optimal cell growth and biodegradation activity at 1% v/v initial diesel concentration, 1 g/L NH4Cl concentration, pH 7 and 1% NaCl during one-factor-at-a-time (OFAT) analyses. Strain AQ5-07 was psychrotolerant based on its optimum growth temperature being near 20 °C. In conventionally optimised media, strain AQ5-07 showed total petroleum hydrocarbons (TPH) mineralisation of 75.83%. However, the optimised condition for TPH mineralisation predicted through statistical response surface methodology (RSM) enhanced the reduction to 90.39% within a 2 days incubation. Our preliminary data support strain AQ5-07 being a potential candidate for real-field soil bioremediation by specifically adopting sludge-phase bioreactor system in chronically cold environments such as Antarctica. The study also confirmed the utility of RSM in medium optimisation.

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103.

Strain MG, isolated from an acidic pond sediment on the island of Milos (Greece), is proposed as a novel species of ferrous iron- and sulfur-oxidizing Acidithiobacillus. Currently, four of the eight validated species of this genus oxidize ferrous iron, and strain MG shares many key characteristics with these four, including the capacities for catalyzing the oxidative dissolution of pyrite and for anaerobic growth via ferric iron respiration. Strain MG also grows aerobically on hydrogen and anaerobically on hydrogen coupled to ferric iron reduction. While the 16S rRNA genes of the iron-oxidizing Acidi-thiobacillus species (and strain MG) are located in a distinct phylogenetic clade and are closely related (98–99% 16S rRNA gene identity), genomic relatedness indexes (ANI/dDDH) revealed strong genomic divergence between strain MG and all sequenced type strains of the taxon, and placed MG as the first cultured representative of an ancestral phylotype of iron oxidizing acidithiobacilli. Strain MG is proposed as a novel species, Acidithiobacillus ferrianus sp. nov. The type strain is MGT (= DSM 107098T = JCM 33084T). Similar strains have been found as isolates or indicated by cloned 16S rRNA genes from several mineral sulfide mine sites.

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104.
Plant and Soil - The genus Denhamia(Celastraceae) includes fifteen Australian species, many of which have a propensity for manganese (Mn) (hyper)accumulation. Among the key aims of this study were...  相似文献   
105.
Antisense oligonucleotides (ASOs) have emerged as a new class of drugs to treat a wide range of diseases, including neurological indications. Spinraza, an ASO that modulates splicing of SMN2 RNA, has shown profound disease modifying effects in Spinal Muscular Atrophy (SMA) patients, energizing efforts to develop ASOs for other neurological diseases. While SMA specifically affects spinal motor neurons, other neurological diseases affect different central nervous system (CNS) regions, neuronal and non-neuronal cells. Therefore, it is important to characterize ASO distribution and activity in all major CNS structures and cell types to have a better understanding of which neurological diseases are amenable to ASO therapy. Here we present for the first time the atlas of ASO distribution and activity in the CNS of mice, rats, and non-human primates (NHP), species commonly used in preclinical therapeutic development. Following central administration of an ASO to rodents, we observe widespread distribution and target RNA reduction throughout the CNS in neurons, oligodendrocytes, astrocytes and microglia. This is also the case in NHP, despite a larger CNS volume and more complex neuroarchitecture. Our results demonstrate that ASO drugs are well suited for treating a wide range of neurological diseases for which no effective treatments are available.  相似文献   
106.
Dispersal is a key process in population and evolutionary ecology. Individual decisions are affected by fitness consequences of dispersal, but these are difficult to measure in wild populations. A long‐term dataset on a geographically closed bird population, the Mauritius kestrel, offers a rare opportunity to explore fitness consequences. Females dispersed further when the availability of local breeding sites was limited, whereas male dispersal correlated with phenotypic traits. Female but not male fitness was lower when they dispersed longer distances compared to settling close to home. These results suggest a cost of dispersal in females. We found evidence of both short‐ and long‐term fitness consequences of natal dispersal in females, including reduced fecundity in early life and more rapid aging in later life. Taken together, our results indicate that dispersal in early life might shape life history strategies in wild populations.  相似文献   
107.

Background

Although the ultrastructure of the schistosome esophageal gland was described >35 years ago, its role in the processing of ingested blood has never been established. The current study was prompted by our identification of MEG-4.1 expression in the gland and the observation of erythrocyte uncoating in the posterior esophagus.

Methodology/Principal Findings

The salient feature of the posterior esophagus, characterized by confocal and electron microscopy, is the enormous increase in membrane surface area provided by the plate-like extensions and basal invaginations of the lining syncytium, with unique crystalloid vesicles releasing their contents between the plates. The feeding process was shown by video microscopy to be divided into two phases, blood first accumulating in the anterior lumen before passing as a bolus to the posterior. There it streamed around a plug of material revealed by confocal microscopy as tethered leucocytes. These were present in far larger numbers than predicted from the volume of the lumen, and in varying states of damage and destruction. Intact erythrocytes were detected in the anterior esophagus but not observed thereafter, implying that their lysis occurred rapidly as they enter the posterior. Two further genes, MEGs 4.2 and 14, were shown to be expressed exclusively in the esophageal gland. Bioinformatics predicted that MEGs 4.1 and 4.2 possessed a common hydrophobic region with a shared motif, while antibodies to SjMEG-4.1 showed it was bound to leucocytes in the esophageal lumen. It was also predicted that MEGs 4.1 and 14 were heavily O-glycosylated and this was confirmed for the former by 2D-electrophoresis and Western blotting.

Conclusions/Significance

The esophageal gland and its products play a central role in the processing of ingested blood. The binding of host antibodies in the esophageal lumen shows that some constituents are antibody targets and could provide a new source of vaccine candidates.  相似文献   
108.
The tumor suppressor PTEN is now understood to regulate cellular processes at the cytoplasmic membrane, where it classically regulates PI3K signaling, as well as in the nucleus where multiple roles in controlling cell cycle and genome stability have been elucidated. Mechanisms that dictate nuclear import and, less extensively, nuclear export of PTEN have been described, however the relevance of these processes in disease states, particularly cancer, remain largely unknown. We investigated the impact of acid ceramidase on the nuclear-cytoplasmic trafficking of PTEN. Immunohistochemical analysis of a human prostate tissue microarray revealed that nuclear PTEN was lost in patients whose tumors had elevated acid ceramidase. We found that acid ceramidase promotes a reduction in nuclear PTEN that is dependent upon sphingosine 1-phosphate-mediated activation of Akt. We were further able to show that sphingosine 1-phosphate promotes formation of a complex between Crm1 and PTEN, and that leptomycin B prevents acid ceramidase and sphingosine 1-phosphate mediated loss of nuclear PTEN, suggesting an active exportin-mediated event. To investigate whether the tumor promoting aspects of acid ceramidase in prostate cancer depend upon its ability to export PTEN from the nucleus, we used enforced nuclear expression of PTEN to study docetaxel-induced apoptosis and cell killing, proliferation, and xenoengraftment. Interestingly, while acid ceramidase was able to protect cells expressing wild type PTEN from docetaxel, promote proliferation and xenoengraftment, acid ceramidase had no impact in cells expressing PTEN-NLS. These findings suggest that acid ceramidase, through sphingosine 1-phosphate, promotes nuclear export of PTEN as a means of promoting tumor formation, cell proliferation, and resistance to therapy.  相似文献   
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