bluuebunny/crossref_metadata_2025_split huggingface dataset:
Translation and manipulation of silicon nanomembranes using holographic optical tweezers
Authors: Oehrlein Stefan M , Sanchez-Perez Jose R , Jacobson RB , Flack Frank S , Kershner Ryan J , Lagally Max G 
Published: August 2011

Abstract
We demonstrate the use of holographic optical tweezers for trapping and manipulating silicon nanomembranes. These macroscopic free-standing sheets of single-crystalline silicon are attractive for use in next-generation flexible electronics. We achieve three-dimensional control by attaching a functionalized silica bead to the silicon surface, enabling non-contact trapping and manipulation of planar structures with high aspect ratios (high lateral size to thickness). Using as few as one trap and trapping powers as low as several hundred milliwatts, silicon nanomembranes can be rotated and translated in a solution over large distances.
On the regularity of the solution for the second initial boundary value problem for hyperbolic systems in domains with conical points
Authors: Hung Nguyen Manh , Anh Nguyen Thanh , Chuc Phung Kim 
Published: August 2011

Abstract
In this paper, we deal with the second initial boundary value problem for higher order hyperbolic systems in domains with conical points. We establish several results on the well-posedness and the regularity of solutions.
Gait training with partial body weight support during overground walking for individuals with chronic stroke: a pilot study
Authors: Sousa Catarina O , Barela José A , Prado-Medeiros Christiane L , Salvini Tania F , Barela Ana MF 
Published: August 2011

Abstract

Background
It is not yet established if the use of body weight support (BWS) systems for gait training is effective per se or if it is the combination of BWS and treadmill that improves the locomotion of individuals with gait impairment. This study investigated the effects of gait training on ground level with partial BWS in individuals with stroke during overground walking with no BWS.

Methods
Twelve individuals with chronic stroke (53.17 ± 7.52 years old) participated of a gait training program with BWS during overground walking, and were evaluated before and after the gait training period. In both evaluations, individuals were videotaped walking at a self-selected comfortable speed with no BWS. Measurements were obtained for mean walking speed, step length, stride length and speed, toe-clearance, durations of total double stance and single-limb support, and minimum and maximum foot, shank, thigh, and trunk segmental angles.

Results
After gait training, individuals walked faster, with symmetrical steps, longer and faster strides, and increased toe-clearance. Also, they displayed increased rotation of foot, shank, thigh, and trunk segmental angles on both sides of the body. However, the duration of single-limb support remained asymmetrical between each side of the body after gait training.

Conclusions
Gait training individuals with chronic stroke with BWS during overground walking improved walking in terms of temporal-spatial parameters and segmental angles. This training strategy might be adopted as a safe, specific and promising strategy for gait rehabilitation after stroke.
Exploiting bounded signal flow for graph orientation based on cause–effect pairs
Authors: Dorn Britta , Hüffner Falk , Krüger Dominikus , Niedermeier Rolf , Uhlmann Johannes 
Published: August 2011

Abstract

Background
We consider the following problem: Given an undirected network and a set of sender–receiver pairs, direct all edges such that the maximum number of "signal flows" defined by the pairs can be routed respecting edge directions. This problem has applications in understanding protein interaction based cell regulation mechanisms. Since this problem is NP-hard, research so far concentrated on polynomial-time approximation algorithms and tractable special cases.

Results
We take the viewpoint of parameterized algorithmics and examine several parameters related to the maximum signal flow over vertices or edges. We provide several fixed-parameter tractability results, and in one case a sharp complexity dichotomy between a linear-time solvable case and a slightly more general NP-hard case. We examine the value of these parameters for several real-world network instances.

Conclusions
Several biologically relevant special cases of the NP-hard problem can be solved to optimality. In this way, parameterized analysis yields both deeper insight into the computational complexity and practical solving strategies.
Coordinated increase in inhibitory and excitatory synapses onto retinal ganglion cells during development
Authors: Soto Florentina , Bleckert Adam , Lewis Renate , Kang Yunhee , Kerschensteiner Daniel , Craig Ann Marie , Wong Rachel OL 
Published: August 2011

Abstract

Background
Neuronal output is shaped by a balance of excitation and inhibition. How this balance is attained in the central nervous system during development is not well understood, and is complicated by the fact that, in vivo, GABAergic and glycinergic synaptogenesis precedes that of glutamatergic synapses. Here, we determined the distributions of inhibitory postsynaptic sites on the dendritic arbors of individual neurons, and compared their developmental patterns with that of excitatory postsynaptic sites. We focused on retinal ganglion cells (RGCs), the output neurons of the retina, which receive excitatory input from bipolar cells and inhibitory input from amacrine cells. To visualize and map inhibitory postsynaptic sites, we generated transgenic mice in which RGCs express fluorescently tagged Neuroligin 2 (YFP-NL2) under the control of the Thy1 promoter. By labeling RGC dendrites biolistically in YFP-NL2-expressing retinas, we were able to map the spatial distribution and thus densities of inhibitory postsynaptic sites on the dendritic arbors of individual large-field RGCs across ages.

Results
We demonstrate that YFP-NL2 is present at inhibitory synapses in the inner plexiform layer by its co-localization with gephyrin, the γ2 subunit of the GABAA receptor and glycine receptors. YFP-NL2 puncta were apposed to the vesicular inhibitory transmitter transporter VGAT but not to CtBP2, a marker of presynaptic ribbons found at bipolar cell terminals. Similar patterns of co-localization with synaptic markers were observed for endogenous NL2. We also verified that expression of YFP-NL2 in the transgenic line did not significantly alter spontaneous inhibitory synaptic transmission onto RGCs. Using these mice, we found that, on average, the density of inhibitory synapses on individual arbors increased gradually until eye opening (postnatal day 15). A small centro-peripheral gradient in density found in mature arbors was apparent at the earliest age we examined (postnatal day 8). Unexpectedly, the adult ratio of inhibitory/excitatory postsynaptic sites was rapidly attained, shortly after glutamatergic synaptogenesis commenced (postnatal day 7).

Conclusion
Our observations suggest that bipolar and amacrine cell synaptogenesis onto RGCs appear coordinated to rapidly attain a balanced ratio of excitatory and inhibitory synapse densities prior to the onset of visual experience.
Vitamin C and asthma in children: modification of the effect by age, exposure to dampness and the severity of asthma
Authors: Hemilä Harri , Al‐Biltagi Mohammed , Baset Ahmed A 
Published: August 2011

AbstractBackgroundWe previously found a significant benefit of vitamin C supplementation in asthmatic children.PurposeTo test whether the effect of vitamin C on asthma is heterogeneous over the participant population.MethodsEgyptian asthmatic children between 7 and 10 years of age (n = 60) were included in the cross‐over trial. They were administered 0.2 grams per day of vitamin C and placebo for separate 6‐week periods. The variation in the vitamin C effect on two clinically relevant outcomes was analyzed: the childhood asthma control test (C‐ACT), which measures the severity of asthma symptoms (the scale ranges from 0 to 27 points, < 20 points indicating unsatisfactory asthma control), and FEV1. We used linear modeling to examine the variation of the vitamin C effect in the subgroups.ResultsThe effect of vitamin C on the C‐ACT was significantly modified by age and baseline C‐ACT levels. In the children aged 7.0‐8.2 years with a baseline C‐ACT of 18 to 19 points, vitamin C increased the C‐ACT score by 4.2 points (95% CI: 3.3‐5.3); whereas in the children aged 8.3‐10 years who had a baseline C‐ACT of 14 to 15 points, vitamin C increased the C‐ACT score by only 1.3 points (95% CI: 0.1‐2.5). The effect of vitamin C on the FEV1 levels was significantly modified by age and exposure to dampness. In the children aged 7.0‐8.2 years with no exposure to dampness, vitamin C increased the FEV1 level by 37% (95% CI: 34‐40%), whereas in the children aged 8.3‐10 years with exposure to dampness or mold in their bedroom more than one year prior to the study, vitamin C increased the FEV1 level by only 21% (95% CI: 18‐25%).ConclusionsWe found strong evidence that the effect of vitamin C on asthmatic children is heterogeneous. Further research is needed to confirm our findings and identify the groups of children who would receive the greatest benefit from vitamin C supplementation.
Aryl hydrocarbon receptor-dependent upregulation of Cyp1b1 by TCDD and diesel exhaust particles in rat brain microvessels
Authors: Jacob Aude , Hartz Anika MS , Potin Sophie , Coumoul Xavier , Yousif Salah , Scherrmann Jean-Michel , Bauer Björn , Declèves Xavier 
Published: August 2011

Abstract

Background
AhR activates the transcription of several target genes including CYP1B1. Recently, we showed CYP1B1 as the major cytochrome P450 (CYP) enzyme expressed in human brain microvessels. Here, we studied the effect of AhR activation by environmental pollutants on the expression of Cyp1b1 in rat brain microvessels.

Methods
Expression of AhR and Cyp1b1 was detected in isolated rat brain microvessels. AhR was immunovisualised in brain microvessel endothelial cells. The effect of AhR ligands on Cyp1b1 expression was studied using isolated brain microvessels after ex vivo and/or in vivo exposure to TCDD, heavy hydrocarbons containing diesel exhaust particles (DEP) or Δ9-tetrahydrocannabinol (Δ9-THC).

Results
After ex vivo exposure to TCDD (a highly potent AhR ligand) for 3 h, Cyp1b1 expression was significantly increased by 2.3-fold in brain microvessels. A single i.p. dose of TCDD also increased Cyp1b1 transcripts (22-fold) and Cyp1b1 protein (2-fold) in rat brain microvessels at 72 h after TCDD. Likewise, DEP treatment (in vivo and ex vivo) strongly induced Cyp1b1 protein in brain microvessels. DEP-mediated Cyp1b1 induction was inhibited by actinomycin D, cycloheximide, or by an AhR antagonist. In contrast, a sub-chronic in vivo treatment with Δ9-THC once daily for 7 seven days had no effect on Cyp1b1 expression

Conclusions
Our results show that TCDD and DEP strongly induced Cyp1b1 in rat brain microvessels, likely through AhR activation.
Lipodystrophies: Genetic and Acquired Body Fat Disorders
Authors: Garg Abhimanyu 
Published: August 2011

Abstract

Context:
Lipodystrophies are heterogeneous, genetic or acquired disorders characterized by selective loss of body fat and predisposition to insulin resistance. The extent of fat loss determines the severity of associated metabolic complications such as diabetes mellitus, hypertriglyceridemia, and hepatic steatosis.

Evidence Acquisition and Synthesis:
Both original and review articles were found via PubMed search reporting on clinical features and management of various types of lipodystrophies and were integrated with the author's knowledge of the field.

Conclusion:
The autosomal recessive congenital generalized lipodystrophy and autosomal dominant familial partial lipodystrophy (FPL) are the two most common types of genetic lipodystrophies. Mutations in AGPAT2, BSCL2, CAV1, and PTRF have been reported in congenital generalized lipodystrophy and in LMNA, PPARG, AKT2, and PLIN1 in FPL. CIDEC is the disease gene for autosomal recessive, FPL and LMNA and ZMPSTE24 for autosomal recessive, mandibuloacral dysplasia-associated lipodystrophy. Recently, an autosomal recessive autoinflammatory lipodystrophy syndrome was reported to be due to PSMB8 mutation. Molecular genetic bases of many rare forms of genetic lipodystrophies remain to be elucidated. The most prevalent subtype of acquired lipodystrophy currently occurs with prolonged duration of protease inhibitor-containing, highly-active antiretroviral therapy in HIV-infected patients. The acquired generalized and partial lipodystrophies are mainly autoimmune in origin and display complement abnormalities. Localized lipodystrophies occur due to drug or vaccine injections, pressure, panniculitis, and other unknown reasons. The current management includes cosmetic surgery and early identification and treatment of metabolic and other complications with diet, exercise, hypoglycemic drugs, and lipid-lowering agents.
Acute Decline in Serum Sclerostin in Response to PTH Infusion in Healthy Men
Authors: Yu Elaine W. , Kumbhani Ruchit , Siwila-Sackman Erica , Leder Benjamin Z. 
Published: August 2011

Abstract

Context:
Animal models suggest that the osteoblast-stimulating actions of PTH are mediated by acute suppression of sclerostin, an inhibitor of the anabolic Wnt pathway. The immediate physiological changes in serum sclerostin in response to PTH infusion have not been reported in human studies.

Objective:
We sought to determine the acute physiological effects of PTH infusion on serum sclerostin and bone turnover markers in healthy adult men.

Design, Setting, and Participants:
Fifty-three healthy adult men underwent an 18-h iv infusion of human PTH(1-34) at a dose of 0.55 U/kg · h.

Outcomes:
Serum levels of ionized calcium, sclerostin, and markers of bone formation (osteocalcin and amino-terminal propeptide of type I procollagen) and bone resorption (C-telopeptide and N-telopeptide) were obtained at 0, 6, 12, and 18 h.

Results:
Serum ionized calcium, C-telopeptide, and N-telopeptide increased, and osteocalcin and amino-terminal propeptide of type I procollagen fell linearly throughout the PTH infusion (P &lt; 0.001 for all). Average ± sem sclerostin levels declined from 936 ± 65 to 813 ± 63 pg/ml at 6 h (P &lt; 0.001) and remained stably suppressed for the duration of the PTH infusion. There were no significant correlations between change in sclerostin and change in bone markers.

Conclusions:
Serum sclerostin declined in response to acute PTH infusion within 6 h in healthy adult men. The early plateau in sclerostin suppression may indicate that maximal stimulation of the Wnt pathway is achieved quickly after exposure to PTH. Our findings support the hypothesis that PTH may mediate its anabolic effects in part via suppression of sclerostin.
Treatment of Androgen Excess in Adolescent Girls: Ethinylestradiol-Cyproteroneacetate Versus Low-Dose Pioglitazone-Flutamide-Metformin
Authors: Ibáñez Lourdes , Diaz Marta , Sebastiani Giorgia , Sánchez-Infantes David , Salvador Cristina , Lopez-Bermejo Abel , de Zegher Francis 
Published: August 2011

Abstract

Objective:
The aim was to perform a first comparison between the effects of a classic therapy and those of a novel treatment for androgen excess in adolescent girls.

Design and Setting:
We conducted a randomized, open-labeled trial at a university hospital.

Participants:
Thirty-four adolescents with hyperinsulinemic androgen excess and without risk of pregnancy participated in the study.

Interventions:
Ethinyl estradiol-cyproterone acetate (EE-CA) vs. a low-dose combination of pioglitazone, flutamide, and metformin (PioFluMet) was administered for 6 months.

Main Outcome Measures:
We assessed hirsutism and acne scores; androgen excess; fasting insulin, lipid profile, C-reactive protein, high molecular-weight adiponectin, leptin, follistatin; carotid intima-media thickness; body composition (absorptiometry); and abdominal fat partitioning (magnetic resonance imaging).

Results:
EE-CA and PioFluMet attenuated the androgen excess comparably but had divergent effects on fasting insulinemia; on circulating cholesterol, triglycerides, C-reactive protein, high molecular-weight adiponectin, leptin, and follistatin; on carotid intima-media thickness; on lean mass; and on abdominal, visceral, and hepatic fat, with all these divergences pointing to a healthier condition on low-dose PioFluMet.

Conclusion:
Low-dose PioFluMet compared favorably to EE-CA in adolescents with androgen excess and without pregnancy risk. The efficacy and safety of low-dose PioFluMet remain to be studied over a longer term and in larger cohorts.
Functional aspects of cytidine-guanosine dinucleotides and their locations in genes
Authors: Varga Franz , Karlic Heidrun , Thaler Roman , Klaushofer Klaus 
Published: August 2011

AbstractOriginally, the finding of a particular distribution of cytidine-guanosine dinucleotides (CpGs) in genomic DNA was considered to be an interesting structural feature of eukaryotic genome organization. Despite a global depletion of CpGs, genes are frequently associated with CpG clusters called CpG islands (CGIs). CGIs are prevalently unmethylated but often found methylated in pathologic situations. On the other hand, CpGs outside of CGIs are generally methylated and are found mainly in the heterochromatic fraction of the genome. Hypomethylation of those CpGs is associated with genomic instability in malignancy. Additionally, CpG-rich and CpG-poor regions, as well as CpG-shores, are defined. Usually, the methylation status inversely correlates with gene expression. Methylation of CpGs, as well as demethylation and generation of hydroxmethyl-cytosines, is strictly regulated during development and differentiation. This review deals with the relevance of the organizational features of CpGs and their relation to each other.
Robust semi-coarsening multilevel preconditioning of biquadratic FEM systems
Authors: Lymbery Maria , Margenov Svetozar 
Published: August 2011

Abstract
While a large amount of papers are dealing with robust multilevel methods and algorithms for linear FEM elliptic systems, the related higher order FEM problems are much less studied. Moreover, we know that the standard hierarchical basis two-level splittings deteriorate for strongly anisotropic problems. A first robust multilevel preconditioner for higher order FEM systems obtained after discretizations of elliptic problems with an anisotropic diffusion tensor is presented in this paper. We study the behavior of the constant in the strengthened CBS inequality for semi-coarsening mesh refinement which is a quality measure for hierarchical two-level splittings of the considered biquadratic FEM stiffness matrices. The presented new theoretical estimates are confirmed by numerically computed CBS constants for a rich set of parameters (coarsening factor and anisotropy ratio). In the paper we consider also the problem of solving efficiently systems with the pivot block matrices arising in the hierarchical basis two-level splittings. Combining the proven uniform estimates with the theory of the Algebraic MultiLevel Iteration (AMLI) methods we obtain an optimal order multilevel algorithm whose total computational cost is proportional to the size of the discrete problem with a proportionality constant independent of the anisotropy ratio.
From forest to field: Perennial fruit crop domestication
Authors: Miller Allison J. , Gross Briana L. 
Published: August 2011

•Premise of the study:Archaeological and genetic analyses of seed‐propagated annual crops have greatly advanced our understanding of plant domestication and evolution. Comparatively little is known about perennial plant domestication, a relevant topic for understanding how genes and genomes evolve in long‐lived species, and how perennials respond to selection pressures operating on a relatively short time scale. Here, we focus on long‐lived perennial crops (mainly trees and other woody plants) grown for their fruits.•Key results:We reviewed (1) the basic biology of long‐lived perennials, setting the stage for perennial domestication by considering how these species evolve in nature; (2) the suite of morphological features associated with perennial fruit crops undergoing domestication; (3) the origins and evolution of domesticated perennials grown for their fruits; and (4) the genetic basis of domestication in perennial fruit crops.•Conclusions:Long‐lived perennials have lengthy juvenile phases, extensive outcrossing, widespread hybridization, and limited population structure. Under domestication, these features, combined with clonal propagation, multiple origins, and ongoing crop–wild gene flow, contribute to mild domestication bottlenecks in perennial fruit crops. Morphological changes under domestication have many parallels to annual crops, but with key differences for mating system evolution and mode of reproduction. Quantitative trait loci associated with domestication traits in perennials are mainly of minor effect and may not be stable across years. Future studies that take advantage of genomic approaches and consider demographic history will elucidate the genetics of agriculturally and ecologically important traits in perennial fruit crops and their wild relatives.
Mémoire et musique rap
Authors: Béru Laurent 
Published: August 2011

Résumé Le rap venu des États-Unis émerge dans les banlieues françaises au début des années 1990. Les rappeurs français expriment une réalité sociale difficile. Leur musique cristallise les représentations et les jeux de pouvoir à l’œuvre dans la société française contemporaine. Si certains s’attirent les foudres des pouvoirs publics, la plupart mettent leur verve au service d’un engagement : en empruntant les clivages ethnoraciaux, ils entreprennent de réécrire l’histoire.
The P2X7 Receptor and Pannexin-1 Are Both Required for the Promotion of Multinucleated Macrophages by the Inflammatory Cytokine GM-CSF
Authors: Lemaire Irma , Falzoni Simonetta , Zhang Bin , Pellegatti Patrizia , Di Virgilio Francesco 
Published: August 2011

Abstract
The P2X7 receptor (P2X7R), an ATP-gated ion channel, has been implicated in the process of cell-to-cell fusion into multinucleated macrophages (MA), but its contribution to MA fusion driven by physiological/pathological stimuli is not clearly established. Based on several lines of evidence, we demonstrate that P2X7R is critical for the induction of multinucleated MA by the inflammatory cytokine GM-CSF: 1) pharmacological inhibition of P2X7R with oxidized ATP (oATP), KN-62, and the selective antagonist A740003 abrogated GM-CSF action on rat alveolar MA and murine peritoneal MA; 2) a murine J774 P2X7 low MA clone, selected for defective P2X7R function, was unresponsive; 3) MA from mice lacking P2X7R failed to respond to GM-CSF, in contrast to wild-type. GM-CSF also stimulated ATP-induced membrane permeabilization in J774 P2X7 high MA and rat alveolar MA, an effect absent in the P2X7 low MA clone and inhibited by the P2X7 blockers oATP and KN-62. Notably, the stimulatory effects of GM-CSF on pore formation and MA fusion were both inhibited by blocking functional Pannexin-1 (Panx-1), and GM-CSF failed to stimulate MA fusion in cells from Panx-1 knockout mice. We provide further evidence that extracellular ATP release from peritoneal MA is dependent on P2X7 but not on Panx-1 expression and that its metabolism to adenosine mediates P2X7-dependent MA fusion. These data demonstrate that both P2X7 and Panx-1 are required for GM-CSF promotion of MA fusion but likely act independently through different signaling pathway(s).