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https://www.readbyqxmd.com/read/28098946/negative-association-between-mr-spectroscopic-glutamate-markers-and-gray-matter-volume-after-alcohol-withdrawal-in-the-hippocampus-a-translational-study-in-humans-and-rats
#1
Ulrich Frischknecht, Derik Hermann, Nuran Tunc-Skarka, Guo-Ying Wang, Markus Sack, Julia van Eijk, Traute Demirakca, Claudia Falfan-Melgoza, Bertram Krumm, Sandra Dieter, Rainer Spanagel, Falk Kiefer, Karl F Mann, Wolfgang H Sommer, Gabriele Ende, Wolfgang Weber-Fahr
BACKGROUND: Both chronic alcohol consumption and alcohol withdrawal lead to neural tissue damage which partly recovers during abstinence. This study investigated withdrawal-associated changes in glutamatergic compounds, markers of neuronal integrity, and gray matter volumes during acute alcohol withdrawal in the hippocampus, a key region in development and maintenance of alcohol dependence in humans and rats. METHODS: Alcohol-dependent patients (N = 39) underwent magnetic resonance imaging (MRI) and MR spectroscopy (MRS) measurements within 24 hours after the last drink and after 2 weeks of abstinence...
January 18, 2017: Alcoholism, Clinical and Experimental Research
https://www.readbyqxmd.com/read/28098843/perm-hypothesis-the-fundamental-machinery-able-to-elucidate-the-role-of-xenobiotics-and-hormesis-in-cell-survival-and-homeostasis
#2
REVIEW
Salvatore Chirumbolo, Geir Bjørklund
In this article the Proteasome, Endoplasmic Reticulum and Mitochondria (PERM) hypothesis is discussed. The complex machinery made by three homeostatic mechanisms involving the proteasome (P), endoplasmic reticulum (ER) and mitochondria (M) is addressed in order to elucidate the beneficial role of many xenobiotics, either trace metals or phytochemicals, which are spread in the human environment and in dietary habits, exerting their actions on the mechanisms underlying cell survival (apoptosis, cell cycle regulation, DNA repair and turnover, autophagy) and stress response...
January 15, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28098577/mitochondria-initiate-and-regulate-sarcopenia
#3
Stephen E Alway, Junaith S Mohamed, Matthew J Myers
We present the hypothesis that an accumulation of dysfunctional mitochondria initiates a signaling cascade leading to motor neuron and muscle fiber death and culminating in sarcopenia. Interactions between neural and muscle cells that contain dysfunctional mitochondria exacerbate sarcopenia. Preventing sarcopenia will require identifying mitochondrial sources of dysfunction that are reversible.
January 16, 2017: Exercise and Sport Sciences Reviews
https://www.readbyqxmd.com/read/28098523/effects-of-psychological-distance-and-need-for-cognitive-closure-on-impression-formation
#4
Ivan Tomić, Mirjana Tonković, Dragutin Ivanec
Based on theoretical and empirical similarities between Construal level theory of psychological distance and the Need for cognitive closure (NFC) theory, it could be hypothesized that psychological distance and NFC represent constructs that overlap to some degree. Since both theories describe judgmental behavior in terms of schematic processing, we hypothesized that primacy effect, a schema-driven phenomenon, is strengthened under the heightened NFC and psychological distance. We tested this hypothesis in an impression formation experiment while manipulating psychological distance and measuring NFC...
January 2017: Journal of General Psychology
https://www.readbyqxmd.com/read/28098457/surface-forces-and-rheology-of-titanium-dioxide-in-the-presence-of-dicarboxylic-acids-from-molecular-interactions-to-yield-stress
#5
E-Jen Teh, Yee-Kwong Leong, Vincent S J Craig
The surface forces and yield stress of titanium dioxide were measured in the presence of dicarboxylic acids in order to understand the molecular basis for the observed rheological response. The yield stress was measured using the static vane technique whilst the surface forces were characterised using an Atomic Force Microscope. The trans and cis isomers of butenedioic acid (fumaric and maleic acids respectively) were chosen as the relative orientation of the carboxylic groups differs substantially. This enables us to test the hypothesis that an increase in adhesion leads to an increase in yield stress as a consequence of the dicarboxylic acids participating in highly directed bridging...
January 18, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28098351/the-elicitation-of-steady-state-visual-evoked-potentials-during-sleep
#6
James J S Norton, Stephen Umunna, Timothy Bretl
This study confirmed the hypothesis that it is possible to elicit SSVEPs through closed eyelids during NREM sleep. To test this hypothesis, SSVEP amplitudes were measured in eight subjects across two conditions of stimulation (stimulation on and stimulation off) and three brain states (waking, light sleep, and deep sleep). Results showed a significant interaction between stimulation and brain state. In particular, EEG activity at the frequency of stimulation was higher during both light sleep and deep sleep in the stimulation on condition than in the stimulation off condition...
January 18, 2017: Psychophysiology
https://www.readbyqxmd.com/read/28098283/high-precision-localized-proton-gradients-and-fluxes-generated-by-a-microelectrode-device-induce-differential-growth-behaviors-of-pollen-tubes
#7
Chengzhi Hu, Hannes Vogler, Marianne Aellen, Naveen Shamsudhin, Bumjin Jang, Jan T Burri, Nino Läubli, Ueli Grossniklaus, Salvador Pané, Bradley J Nelson
Pollen tubes are tip-growing plant cells that deliver the sperm cells to the ovules for double fertilization of the egg cell and the endosperm. Various directional cues can trigger the reorientation of pollen tube growth direction on their passage through the female tissues. Among the external stimuli, protons serve an important, regulatory role in the control of pollen tube growth. The generation of local guidance cues has been challenging when investigating the mechanisms of perception and processing of such directional triggers in pollen tubes...
January 18, 2017: Lab on a Chip
https://www.readbyqxmd.com/read/28098234/maternal-cortisol-stimulates-neurogenesis-and-affects-larval-behaviour-in-zebrafish
#8
Carol Best, Deborah M Kurrasch, Mathilakath M Vijayan
Excess glucocorticoid transferred from stressed mother to the embryo affects developing vertebrate offspring, but the underlying programming events are unclear. In this study, we tested the hypothesis that increased zygotic glucocorticoid deposition, mimicking a maternal stress scenario, modifies early brain development and larval behaviour in zebrafish (Danio rerio). Cortisol was microinjected into the yolk at one cell-stage, to mimic maternal transfer, and the larvae [96 hours post-fertilization (hpf)] displayed increased activity in light and a reduction in thigmotaxis, a behavioural model for anxiety, suggesting an increased propensity for boldness...
January 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28098155/the-geometric-nature-of-weights-in-real-complex-networks
#9
Antoine Allard, M Ángeles Serrano, Guillermo García-Pérez, Marián Boguñá
The topology of many real complex networks has been conjectured to be embedded in hidden metric spaces, where distances between nodes encode their likelihood of being connected. Besides of providing a natural geometrical interpretation of their complex topologies, this hypothesis yields the recipe for sustainable Internet's routing protocols, sheds light on the hierarchical organization of biochemical pathways in cells, and allows for a rich characterization of the evolution of international trade. Here we present empirical evidence that this geometric interpretation also applies to the weighted organization of real complex networks...
January 18, 2017: Nature Communications
https://www.readbyqxmd.com/read/28098151/juvenile-myelomonocytic-leukemia-associated-variants-are-associated-with-neo-natal-lethal-noonan-syndrome
#10
Heather Mason-Suares, Diana Toledo, Jean Gekas, Katherine A Lafferty, Naomi Meeks, M Cristina Pacheco, David Sharpe, Thomas E Mullen, Matthew S Lebo
Gain-of-function variants in some RAS-MAPK pathway genes, including PTPN11 and NRAS, are associated with RASopathies and/or acquired hematological malignancies, most notably juvenile myelomonocytic leukemia (JMML). With rare exceptions, the spectrum of germline variants causing RASopathies does not overlap with the somatic variants identified in isolated JMML. Studies comparing these variants suggest a stronger gain-of-function activity in the JMML variants. As JMML variants have not been identified as germline defects and have a greater impact on protein function, it has been speculated that they would be embryonic lethal...
January 18, 2017: European Journal of Human Genetics: EJHG
https://www.readbyqxmd.com/read/28097874/through-scaffold-modification-to-3-5-diaryl-4-5-dihydroisoxazoles-new-potent-and-selective-inhibitors-of-monoamine-oxidase-b
#11
Rita Meleddu, Simona Distinto, Roberto Cirilli, Stefano Alcaro, Matilde Yanez, Maria Luisa Sanna, Angela Corona, Claudia Melis, Giulia Bianco, Peter Matyus, Filippo Cottiglia, Elias Maccioni
3,5-Diaryl-4,5-dihydroisoxazoles were synthesized and evaluated as monoamine oxidase (MAO) enzyme inhibitors and iron chelators. All compounds exhibited selective inhibitory activity towards the B isoform of MAO in the nanomolar concentration range. The best performing compound was preliminarily evaluated for its ability to bind iron II and III cations, indicating that neither iron II nor iron III is coordinated. The best compounds racemic mixtures were separated and single enantiomers inhibitory activity evaluated...
December 2017: Journal of Enzyme Inhibition and Medicinal Chemistry
https://www.readbyqxmd.com/read/28097738/enhanced-predictive-signalling-in-schizophrenia
#12
Katharina Schmack, Marcus Rothkirch, Josef Priller, Philipp Sterzer
Positive symptoms of schizophrenia such as delusions and hallucinations are thought to arise from an alteration in predictive mechanisms of the brain. Here, we empirically tested the hypothesis that schizophrenia is associated with an enhanced signalling of higher-level predictions that shape perception into conformity with acquired beliefs. Twenty-one patients with schizophrenia and twenty-eight healthy controls matched for age and gender took part in a functional magnetic resonance imaging (fMRI) experiment that assessed the effect of an experimental manipulation of cognitive beliefs on the perception of an ambiguous visual motion stimulus...
January 18, 2017: Human Brain Mapping
https://www.readbyqxmd.com/read/28097727/energetics-kinetics-and-pathway-of-snare-folding-and-assembly-revealed-by-optical-tweezers
#13
REVIEW
Yongli Zhang
Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) are universal molecular engines that drive membrane fusion. Particularly, synaptic SNAREs mediate fast calcium-triggered fusion of neurotransmitter-containing vesicles with plasma membranes for synaptic transmission, the basis of all thought and action. During membrane fusion, complementary SNAREs located on two apposed membranes (often called t- and v-SNAREs) join together to assemble into a parallel four-helix bundle, releasing the energy to overcome the energy barrier for fusion...
January 18, 2017: Protein Science: a Publication of the Protein Society
https://www.readbyqxmd.com/read/28097672/collective-resistance-despite-complicity-high-identifiers-rise-above-the-legitimization-of-disadvantage-by-the-in-group
#14
Gloria Jiménez-Moya, Rosa Rodríguez-Bailón, Russell Spears, Soledad de Lemus
How do individuals deal with group disadvantage when their fellow in-group members conceive it as legitimate? Integrating research on the normative conflict model (Packer, 2008, Pers. Soc. Psychol. Rev., 12, 50) and collective action, we expect high identifiers to reject the in-group norm of legitimacy that justifies the inequality, and to assert that the group is actually able and willing to contest the disadvantage by collective means. In Study 1 and Study 2, we tested this hypothesis in different intergroup contexts...
January 17, 2017: British Journal of Social Psychology
https://www.readbyqxmd.com/read/28097663/the-evolution-of-male-nuptial-colour-in-a-sexually-dimorphic-group-of-fishes-percidae-etheostomatinae
#15
P J Ciccotto, T C Mendelson
To test hypotheses explaining variation in elaborate male colouration across closely related species groups, ancestral-state reconstructions and tests of phylogenetic signal and correlated evolution were used to examine the evolution of male body and fin colouration in a group of sexually dichromatic stream fishes known as darters (Percidae: Etheostomatinae). The presence or absence of red-orange and blue-green male colour traits were scored across six body regions in 99 darter species using a recently estimated amplified fragment length polymorphism (AFLP) phylogeny for comparative analyses...
January 18, 2017: Journal of Fish Biology
https://www.readbyqxmd.com/read/28097510/when-headache-warns-of-homeostatic-threat-the-metabolic-headaches
#16
REVIEW
Parneet Grewal, Jonathan H Smith
Headache attributable to disorders of homeostasis represents a diverse diagnostic category in which external (i.e., high-altitude) or internal (i.e., fasting) demands exceed homeostatic capacity, resulting in symptomatic headaches. Metabolic headaches, especially fasting headache, have been observed to be common in the general population. In many cases, a history of migraine is a risk factor, consistent with the hypothesis of an adaptive, evolutionary role of headache to warn against environmental and physiological threats...
January 2017: Current Neurology and Neuroscience Reports
https://www.readbyqxmd.com/read/28097448/remission-rate-is-not-dependent-on-the-presence-of-antinuclear-antibodies-in-juvenile-idiopathic-arthritis
#17
M Glerup, T Herlin, M Twilt
Recently, it has been hypothesized that the subcategories of the ILAR classification of juvenile idiopathic arthritis (JIA) are not homogeneous, and that the presence of antinuclear antibodies (ANA) should lead to a separate entity. Therefore, the aim of this study was to evaluate ANA positivity as a predictor of achieving remission. A retrospective single-center cohort study including all JIA patients diagnosed between January 2000 and May 2014. A minimum follow-up of 1 year was required plus the ANA status...
January 17, 2017: Clinical Rheumatology
https://www.readbyqxmd.com/read/28097431/placental-dapk1-and-autophagy-marker-lc3b-ii-are-dysregulated-by-tnf-%C3%AE-in-a-gestational-age-dependent-manner
#18
Andreas Prokesch, Astrid Blaschitz, Tamara Bauer, Gerit Moser, Ursula Hiden, Julianna Zadora, Ralf Dechend, Florian Herse, Martin Gauster
Autophagy, a cell-survival process responsible for degradation of protein aggregates and damaged organelles, is increasingly recognized as another mechanism essential for human placentation. A substantial body of experiments suggests inflammation and oxidative stress as the underlying stimuli for altered placental autophagy, giving rise to placenta dysfunction and pregnancy pathologies. Here, the hypothesis is tested whether or not pro-inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-α are able to influence the expression profile of autophagy genes in human first-trimester villous placenta...
January 17, 2017: Histochemistry and Cell Biology
https://www.readbyqxmd.com/read/28097330/electroencephalographic-periodic-discharges-and-frequency-dependent-brain-tissue-hypoxia-in-acute-brain-injury
#19
Jens Witsch, Hans-Peter Frey, J Michael Schmidt, Angela Velazquez, Cristina M Falo, Michael Reznik, David Roh, Sachin Agarwal, Soojin Park, E Sander Connolly, Jan Claassen
Importance: Periodic discharges (PDs) that do not meet seizure criteria, also termed the ictal interictal continuum, are pervasive on electroencephalographic (EEG) recordings after acute brain injury. However, their association with brain homeostasis and the need for clinical intervention remain unknown. Objective: To determine whether distinct PD patterns can be identified that, similar to electrographic seizures, cause brain tissue hypoxia, a measure of ongoing brain injury...
January 9, 2017: JAMA Neurology
https://www.readbyqxmd.com/read/28097204/genomics-implicates-adaptive-and-innate-immunity-in-alzheimer-s-and-parkinson-s-diseases
#20
Sarah A Gagliano, Jennie G Pouget, John Hardy, Jo Knight, Michael R Barnes, Mina Ryten, Michael E Weale
OBJECTIVES: We assessed the current genetic evidence for the involvement of various cell types and tissue types in the etiology of neurodegenerative diseases, especially in relation to the neuroinflammatory hypothesis of neurodegenerative diseases. METHODS: We obtained large-scale genome-wide association study (GWAS) summary statistics from Parkinson's disease (PD), Alzheimer's disease (AD), and amyotrophic lateral sclerosis (ALS). We used multiple sclerosis (MS), an autoimmune disease of the central nervous system, as a positive control...
December 2016: Annals of Clinical and Translational Neurology
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