julilili42/papers huggingface dataset:
Enhancement of gene expression and melanin production of human tyrosinase gene loaded in elastic cationic niosomes
2012-03-23

Abstract Objectives Disturbance in the synthesis of tyrosinase might be one of the major causes of vitiligo. The enhancement of tyrosinase gene expression and melanin production by loading the plasmid in elastic cationic niosomes was investigated in tyrosinase gene knocked out human melanoma (M5) cells and in tyrosine-producing mouse melanoma (B16F10) cells. Methods Niosomes composed of Tween 61/cholesterol/dimethyl dioctadecyl ammonium bromide at 1 : 1 : 0.5 molar ratio were prepared by the freeze-dried empty liposomes method. The thin lipid film was redissolved in distilled water or 25% ethanol to obtain the non-elastic or elastic cationic niosomes, respectively. Key findings The maximum loading of the plasmid in non-elastic and elastic niosomes was 130 and 100 μg per 16 mg of the niosomal contents, respectively. The plasmid-loaded elastic cationic niosomes exhibited high specific tyrosinase activity of 1.66 and 1.50 fold in M5 cells and 6.81 and 4.37 fold in B16F10 cells compared with the free plasmid and the plasmid-loaded non-elastic cationic niosomes, respectively. Conclusions This study has demonstrated not only the enhancement of the expression of human tyrosinase gene by loading in elastic cationic niosomes, but also the potential application of this gene delivery system for the further development of vitiligo gene therapy.
Seeing You or the Scene? Self-Construals Modulate Inhibitory Mechanisms of Attention
2012-03-23

It has often been shown that independent self-construals (emphasizing personal uniqueness) coincide with an analytic, context-independent style of information processing whereas interdependent self-construals (emphasizing relatedness with others) promote holistic, context-dependent processing. The present study suggests that these cognitive variations between different self-construals can be accounted for by higher order cognitive functions for the control of ongoing mental operations (i.e., executive functions). Using an experimental paradigm, we showed naturalistic pictures displaying a face and a place superimposed on each other. On each trial, one of these dimensions served as a target (depicted in magenta), while the other served as a distractor (depicted in gray). The results showed that independency primed participants were less affected by distractors appearing in the presence of a target (i.e., smaller interference effect) than interdependency primed participants. Importantly, the independency primed participants revealed evidence of mental inhibition of distractors, showing longer reaction times when previously ignored distractors subsequently became targets (i.e., a negatively signed priming effect). Thus, our study is the first to suggest that differences in fundamental processes of cognitive control, namely, the inhibition of automatically triggered (but inappropriate) response tendencies, are the driving force behind the many previously reported differences between individuals primed for independency versus interdependency.
The differential effects of school tracking on psychometric intelligence: Do academic-track schools make students smarter?
2012-03-26

Prior research has shown that quantity of schooling affects the development of intelligence in childhood and adolescence. However, it is still debated whether other aspects of schooling--such as ability tracking or, more generally, school quality--can also influence intelligence. In this study, the authors analyzed intelligence gains in academic- and vocational-track schools in Germany, testing for differential effects of school quality (academic vs. vocational track) on psychometric intelligence. Longitudinal data were obtained from a sample of N = 1,038 Grade 7 and 10 students in 49 schools. A nonverbal reasoning test was used as an indicator of general psychometric intelligence, and relevant psychological and social background variables were included in the analyses. Propensity score matching was used to control for selection bias. Results showed a positive effect of attending the academic track.
Interaction with plant transcription factors can mediate nuclear import of phytochrome B
2012-03-26

Phytochromes (phy) are red/far-red–absorbing photoreceptors that regulate the adaption of plant growth and development to changes in ambient light conditions. The nuclear transport of the phytochromes upon light activation is regarded as a key step in phytochrome signaling. Although nuclear import of phyA is regulated by the transport facilitators far red elongated hypocotyl 1 (FHY1) and fhy1-like, an intrinsic nuclear localization signal was proposed to be involved in the nuclear accumulation of phyB. We recently showed that nuclear import of phytochromes can be analyzed in a cell-free system consisting of isolated nuclei of the unicellular green algae Acetabularia acetabulum . We now show that this system is also versatile to elucidate the mechanism of the nuclear transport of phyB. We tested the nuclear transport characteristics of full-length phyB as well as N- and C-terminal phyB fragments in vitro and showed that the nuclear import of phyB can be facilitated by phytochrome-interacting factor 3 (PIF3). In vivo measurements of phyB nuclear accumulation in the absence of PIF1, -3, -4, and -5 indicate that these PIFs are the major transport facilitators during the first hours of deetiolation. Under prolonged irradiations additional factors might be responsible for phyB nuclear transport in the plant.
Predictive factors for neurocognitive function and Quality of Life after surgical treatment for Cushing's disease and acromegaly.
2012-03-26

The current status of disease plays a subordinate role in postoperative outcome concerning QoL and neurocognition in either pathology. A possible explanation might be the considerably improved endocrinopathy after treatment compared to untreated patients, even if no cure is achieved. The lasting impairments might be explained by irreversible changes that have occurred during the active phase of the disease.
Microscopic derivation of Ginzburg-Landau theory
2012-03-26

We give the first rigorous derivation of the celebrated Ginzburg-Landau (GL) theory, starting from the microscopic Bardeen-Cooper-Schrieffer (BCS) model. Close to the critical temperature, GL arises as an effective theory on the macroscopic scale. The relevant scaling limit is semiclassical in nature, and semiclassical analysis, with minimal regularity assumptions, plays an important part in our proof.
What Information Does The Eye Send To The Brain? Recording The Entire Visual Output At A Single Retinal Location
2012-03-26

Right at the first synapse in the mammalian retina, the stream of incoming visual information is split into multiple parallel information channels, preprocessed in the retinal network and relayed to the brain via different types of retinal ganglion cells (RGCs). About 20 different morphological RGC types have been described, with each RGC population tiling the retinal surface with its dendritic arbors. Here, we simultaneously record from all RGC types at one retinal location to obtain a complete sample of the information sent to the brain and to understand how the representation of spatio-temporal information in a local image patch is distributed across different RGC types. Here show that retinal ganglion cells can be clustered into functionally defined classes based on their Ca2+-responses to simple light stimuli. We recorded light-evoked Ca2+ activity at single-cell resolution from groups of more than 500 neighboring RGCs loaded with synthetic Ca2+ indicator dyes in whole-mounted mouse retina using two-photon (2P) microscopy. We used a simple full-field light stimulus composed of luminance changes and a temporal frequency chirp. Over 80% of the cells responded reliably to the full field stimulus. Single cell activity patterns could be clustered into more than 15 functionally distinct types using a simple k-means algorithm, yielding about 40% ON cells, 25% ON/OFF and 15% OFF cells, in agreement with previous reports. In addition, presentation of spatially modulated stimuli such as moving bars and checker-boards allowed us to quickly and reliably identify different previously described functional types such as direction selective GCs. We will further verify the functional clustering by morphological identification or patch-clamp recordings. This is possible because the imaged RGCs remain accessible to microelectrodes and, thus, can be dye-filled for morphological identification or targeted for patch-clamp recordings, in contrast to multi-electrode recordings. We now aim to refine our battery of simple stimuli to be able to functionally cluster all &gt;20 morphologically described RGCs in the mouse retina. Our approach allows us to create an inventory of all retinal ganglion cells present at a single retinal location. This local retinal “information fingerprint” should be very informative, not only for our understanding of neuronal computations in the healthy retina, but also as a research tool for evaluating specific functional deficiencies in diseased or degenerating retinae.
Use of cytomegalovirus hyperimmunoglobulin for prevention of congenital cytomegalovirus disease: a retrospective analysis
2012-03-27

Abstract Aims: The aim of this study was to investigate the current prenatal “off-label use” of cytomegalovirus hyperimmunoglobulin (CMV-HIG) in the prevention and treatment of congenital CMV (cCMV) infection, including the long-term outcome of the children. Methods: This retrospective observational study comprised mothers and their children, born between January 1, 2006, and October 30, 2010. Prenatal CMV-HIG was administered after diagnosis of primary CMV infection of the mother. Clinical and virological data were collected from maternal and pediatric medical and laboratory reports. Follow-up was 12–36 months after birth. Results: Forty-two women and 43 children met the study criteria. In total, 40 mothers and six unborn infants received 115 doses of CMV-HIG. The treatment group (TG; CMV-DNA polymerase chain reaction-positive amniotic fluid) included four mothers; the multinomial group (MG; CMV-positive mother and unknown CMV status of fetus) included 38 mothers (39 infants). For the four unborn infants in TG, CMV-HIG was administered either intraumbilically or into the amniotic fluid; three of the four mothers received intravenous CMV-HIG. Three children in TG remained CMV-positive and were asymptomatic at birth and during follow-up. One infant in TG had symptomatic cCMV infection in utero , at birth, and during follow-up. In MG, 37 of 38 women received intravenous CMV-HIG and two of 39 infants received CMV-HIG in utero . In total, 9 (23.1%) of 39 children in MG were positive for cCMV (including a terminated pregnancy). All eight instances of cCMV infection at birth in MG were asymptomatic at birth and during follow-up. The fetus from the terminated pregnancy showed no sonographic symptoms of cCMV infection. No severe side effect occurred in 115 CMV-HIG applications. Conclusion: CMV-HIG was well tolerated. Compared with published untreated mother-child pairs, we observed a trend toward a smaller risk for intrauterine CMV transmission following CMV-HIG application. Signs of prenatal cCMV disease were not reversed after CMV-HIG.
Late Stage Infection in Sleeping Sickness
2012-03-27

At the turn of the 19(th) century, trypanosomes were identified as the causative agent of sleeping sickness and their presence within the cerebrospinal fluid of late stage sleeping sickness patients was described. However, no definitive proof of how the parasites reach the brain has been presented so far. Analyzing electron micrographs prepared from rodent brains more than 20 days after infection, we present here conclusive evidence that the parasites first enter the brain via the choroid plexus from where they penetrate the epithelial cell layer to reach the ventricular system. Adversely, no trypanosomes were observed within the parenchyma outside blood vessels. We also show that brain infection depends on the formation of long slender trypanosomes and that the cerebrospinal fluid as well as the stroma of the choroid plexus is a hostile environment for the survival of trypanosomes, which enter the pial space including the Virchow-Robin space via the subarachnoid space to escape degradation. Our data suggest that trypanosomes do not intend to colonize the brain but reside near or within the glia limitans, from where they can re-populate blood vessels and disrupt the sleep wake cycles.
The transcription factor Grainy head and the steroid hormone ecdysone cooperate during differentiation of the skin of Drosophila melanogaster
2012-03-27

Abstract The arthropod epidermis is an epithelium that deposits the apical cuticle, which is a stratified extracellular matrix (ECM) protecting the animal against pathogens, preventing dehydration and also serving as an exoskeleton. Differentiation of the cuticle conceivably implies coordinated production, secretion and localization of its components. The underlying molecular mechanisms are poorly explored. In this work, we show that the transcription factor Grainy head and the steroid hormone ecdysone drive the production of two partially overlapping sets of cuticle factors. Nevertheless, Grainy head is needed to modulate the expression of ecdysone signalling factors; the significance of this cross‐talk is yet unclear. In addition, we found that ecdysone signalling negatively regulates its own impact. In conclusion, our findings suggest that at least two independently triggered pathways have evolved in parallel to cooperatively ensure the stereotypic implementation of the cuticle. As Grainy head is also essential for epithelial differentiation in vertebrates, we speculate that it acts to decode the ancient skin programme common to all animals. Full differentiation of the skin necessitates a second, complementing taxon‐specific programme that requires its own decoder, which is represented by ecdysone in arthropods, whereas the vertebrate specific one remains to be identified.
Patterns of sun protection for young children: do we deliver the right sun-protection messages?
2012-03-27

Conflicts of interest None declared. ORIGINAL ARTICLE, p.803 The reduction of ultraviolet (UV) radiation exposure is the main strategy in order to prevent skin cancer, and early childhood before the age of 6 years is regarded as a particularly vulnerable period of life. The article of Li and colleagues1 is based upon a population‐based questionnaire survey of 2619 parents with young children aged 3–6 years. The authors emphasize that patterns of sun protection differ between sunny holidays with a higher degree of sun‐protective activities and everyday outdoor activities with less sun‐protective attention. Interestingly, better knowledge about sun exposure and skin cancer affected the sun‐protective behaviour only in the beach environment, but not in everyday life. Furthermore, with increasing age the attention for sun protection decreased. The data of this study allow additional insight into the sun‐protective behaviour of parents with young children: they rely mainly on the protective effect of sunscreens. In the beach setting 98·6% regularly used sunscreens and 79·2% even several times a day. However, only 29·7% used T‐shirts and only 2·5% long‐sleeved shirts. T‐shirts were used much more often in the garden setting, by 84·6%, but sunscreens (88·6%) were the most frequently used measure of sun protection also in this setting.
Active encoding of decisions about stimulus absence in primate prefrontal cortex neurons
2012-03-28

Judging the presence or absence of a stimulus is likely the most basic perceptual decision. A fundamental difference of detection tasks in contrast to discrimination tasks is that only the stimulus presence decision can be inferred from sensory evidence, whereas the alternative decision about stimulus absence lacks sensory evidence by definition. Detection decisions have been studied in an intentional, action-based framework, in which decisions were regarded as intentions to pursue particular actions. These studies have found that only stimulus-present decisions are actively encoded by neurons, whereas the decision about the absence of a stimulus does not affect default neuronal responses. We tested whether this processing mechanism also holds for abstract detection decisions that are dissociated from motor preparation. We recorded single-neuron activity from the prefrontal cortex (PFC) of monkeys performing a visual detection task that forced a report-independent decision. We not only found neurons that actively encoded the subjective decision of monkeys about the presence of a stimulus, but also cells responding actively for the decision about the absence of stimuli. These results suggest that abstract detection decisions are processed in a different way compared with the previously reported action-based decisions. In a report-independent framework, neuronal networks seem to generate a second set of neurons actively encoding the absence of sensory stimulation, thus translating decisions into abstract categories. This mechanism may allow the brain to “buffer” a decision in a nonmovement-related framework.
Bayesian online clustering of eye movement data
2012-03-28

The task of automatically tracking the visual attention in dynamic visual scenes is highly challenging. To approach it, we propose a Bayesian online learning algorithm. As the visual scene changes and new objects appear, based on a mixture model, the algorithm can identify and tell visual saccades (transitions) from visual fixation clusters (regions of interest). The approach is evaluated on real-world data, collected from eye-tracking experiments in driving sessions.
Impact of polyelectrolytes and their corresponding multilayers to human primary endothelial cells
2012-03-28

The layer-by-layer technique, which allows simple preparation of polyelectrolyte multilayers, came into the focus of research for development of functionalized medical devices. Numerous literature exist that concentrate on the film build-up and the behaviour of cells on polyelectrolyte multilayers. However, in case of very soft polyelectrolyte multilayers, studies of the cell behaviour on these films are sometimes misleading with regard to clinical applications because cells do not die due to cytotoxicity but due to apoptosis by missing cell adhesion. It turns out that the adhesion in vitro, and thus, the viability of cells on polyelectrolyte multilayers is mostly influenced by their mechanical properties. In order to decide, which polyelectrolyte multilayers are suitable for implants, we take this problem into account by putting the substrates with soft films on top of pre-cultured human primary endothelial cells (‘reverse assay’). Hence, the present work aims giving a more complete and reliable study of typical polyelectrolyte multilayers with regard to clinical applications. In particular, coatings consisting of hyaluronic acid and chitosan as natural polymers and sulfonated polystyrene and polyallylamine hydrochlorite as synthetic polymers were studied. The adsorption of polyelectrolytes was characterized by physico-chemical methods which show regular buildup. Biological examination of the native or modified polyelectrolyte multilayers was based on their effect to cell adhesion and morphology of endothelial cells by viability assays, immunostaining and scanning electron microscopy. Using the standard method, which is typically applied in literature – seeding cells on top of films – shows that the best adhesion and thus, viability can be achieved using sulfonated polystyrene/polyallylamine hydrochlorite. However, putting the films on top of endothelial cells reveals that hyaluronic acid/chitosan may also be suitable for clinical applications: This result is especially remarkable, since hyaluronic acid and chitosan mediate per se no cytotoxic effects, whereas the individual polyelectrolytes, sulfonated polystyrene and polyallylamine hydrochlorite, and their complexes show slight cytotoxicity.
Possible dark energy imprints in the gravitational wave spectrum of mixed neutron-dark-energy stars
2012-03-28

In the present paper we study the oscillation spectrum of neutron stars containing both ordinary matter and dark energy in different proportions. Within the model we consider, the equilibrium configurations are numerically constructed and the results show that the properties of the mixed neuron-dark-energy star can differ significantly when the amount of dark energy in the stars is varied. The oscillations of the mixed neuron-dark-energy stars are studied in the Cowling approximation. As a result we find that the frequencies of the fundamental mode and the higher overtones are strongly affected by the dark energy content. This can be used in the future to detect the presence of dark energy in the neutron stars and to constrain the dark-energy models.
Human Pregnane X Receptor Genotype of the Donor but Not of the Recipient Is a Risk Factor for Delayed Graft Function After Renal Transplantation
2012-03-28

Delayed graft function (DGF) is an important complication in renal transplantation, contributing significantly to decrease in long-term allograft survival. In addition to donor- and recipient-related risk factors such as immunosuppression, altered renal excretion of xenobiotics by membrane transporters may influence DGF. Using DNA samples from recipients and donors, we assessed the impact on DGF of genetic variants in P-glycoprotein (ABCB1), multidrug resistance protein 2 (ABCC2), and the nuclear pregnane X receptor (PXR/NR1I2), which regulates the transcription of enzymes and transporters. In our local cohort of renal transplant recipients (n = 178), DGF occurred in 27.5%. The PXR 8055TT genotype of the donor only (not of the recipient) was significantly associated with an increased risk for DGF. This finding emerged from univariate as well as multivariate logistic regression analysis including 16 nongenetic factors and held true after correction for multiple testing. Our findings provide the first evidence that PXR may be associated with risk of DGF, independent of previously identified risk factors.
Platelets Contribute to the Pathogenesis of Experimental Autoimmune Encephalomyelitis
2012-03-29

Rationale: Multiple sclerosis (MS) and its mouse model, experimental autoimmune encephalomyelitis (EAE), are inflammatory disorders of the central nervous system (CNS). The function of platelets in inflammatory and autoimmune pathologies is thus far poorly defined. Objective: We addressed the role of platelets in mediating CNS inflammation in EAE. Methods and Results: We found that platelets were present in human MS lesions as well as in the CNS of mice subjected to EAE but not in the CNS from control nondiseased mice. Platelet depletion at the effector-inflammatory phase of EAE in mice resulted in significantly ameliorated disease development and progression. EAE suppression on platelet depletion was associated with reduced recruitment of leukocytes to the inflamed CNS, as assessed by intravital microscopy, and with a blunted inflammatory response. The platelet-specific receptor glycoprotein Ibα (GPIbα) promotes both platelet adhesion and inflammatory actions of platelets and targeting of GPIbα attenuated EAE in mice. Moreover, targeting another platelet adhesion receptor, glycoprotein IIb/IIIa (GPIIb/IIIa), also reduced EAE severity in mice. Conclusions: Platelets contribute to the pathogenesis of EAE by promoting CNS inflammation. Targeting platelets may therefore represent an important new therapeutic approach for MS treatment.