49 research outputs found
Transduplication resulted in the incorporation of two protein-coding sequences into the Turmoil-1 transposable element of C. elegans
Transposable elements may acquire unrelated gene fragments into their
sequences in a process called transduplication. Transduplication of
protein-coding genes is common in plants, but is unknown of in animals. Here,
we report that the Turmoil-1 transposable element in C. elegans has
incorporated two protein-coding sequences into its inverted terminal repeat
(ITR) sequences. The ITRs of Turmoil-1 contain a conserved RNA recognition
motif (RRM) that originated from the rsp- 2 gene and a fragment from the
protein-coding region of the cpg-3 gene. We further report that an open reading
frame specific to C. elegans may have been created as a result of a Turmoil-1
insertion. Mutations at the 5' splice site of this open reading frame may have
reactivated the transduplicated RRM moti
Age-dependent effects of microglial inhibition in vivo on Alzheimerâs disease neuropathology using bioactive-conjugated iron oxide nanoparticles
Background: Tau dysfunction is believed to be the primary cause of neurodegenerative disorders referred to as tauopathies, including Alzheimerâs disease, Pickâs disease, frontotemporal dementia and Parkinsonism. The role of microglial cells in the pathogenesis of tauopathies is still unclear. The activation of microglial cells has been correlated with neuroprotective effects through the release of neurotrophic factors and through clearance of cell debris and phagocytosis of cells with intracellular inclusions. In contrast, microglial activation has also been linked with chronic neuroinflammation contributing to the development of neurodegenerative diseases such as tauopathies. Microglial activation has been recently reported to precede tangle formation and the attenuation of tau pathology occurs after immunosuppression of transgenic mice. Methods: Here we report the specific inhibition of microglial cells in rTg4510 tau-mutant mice by using fibrin Îł377-395 peptide conjugated to iron oxide (Îł-Fe2O3) nanoparticles of 21 ± 3.5 nm diameter. Results: Stabilization of the peptide by its covalent conjugation to the Îł-Fe2O3 nanoparticles significantly decreased the number of the microglial cells compared to the same concentration of the free peptide. The specific microglial inhibition induces different effects on tau pathology in an age dependent manner. The reduction of activation of microglial cells at an early age increases the number of neurons with hyperphosphorylated tau in transgenic mice. In contrast, reduction of activation of microglial cells reduced the severity of the tau pathology in older mice. The number of neurons with hyperphosphorylated tau and the number of neurons with tangles are reduced than those in animals not receiving the fibrin Îł377-395 peptide-nanoparticle conjugate. Conclusions: These results demonstrate a differential effect of microglial activity on tau pathology using the fibrin Îł377-395 peptide-nanoparticle conjugate, depending on age and/or stage of the neuropathological accumulation and aggregation
Human-based immune responsive in vitro infection models for validation of novel TLR4 antagonists identified by computational discovery
Infectious diseases are still a major problem worldwide. This includes microbial infections, with a constant increase in resistance to the current anti-infectives employed. Toll-like receptors (TLRs) perform a fundamental role in pathogen recognition and activation of the innate immune response. Promising new approaches to combat infections and inflammatory diseases involve modulation of the host immune system via TLR4. TLR4 and its co-receptors MD2 and CD14 are required for immune response to fungal and bacterial infection by recognition of microbial cell wall components, making it a prime target for drug development. To evaluate the efficacy of anti-infective compounds early on, we have developed a series of human-based immune responsive infection models, including immune responsive 3D-skin infection models for modeling fungal infections. By using computational methods: pharmacophore modeling and molecular docking, we identified a set of 46 potential modulators of TLR4, which were screened in several tests systems of increasing complexity, including immune responsive 3D-skin infection models. We could show a strong suppression of cytokine and chemokine response induced by lipopolysacharide (LPS) and Candida albicans for individual compounds. The development of human-based immune responsive assays provides a more accurate and reliable basis for development of new anti-inflammatory or immune-modulating drugs.Fraunhofer ICON grantInternational Cooperation and Networking grantYissu
Total serum cholinesterase activity predicts hemodynamic changes during exercise and associates with cardiac troponin detection in a sex-dependent manner.
BACKGROUND: Imbalanced autonomic nervous system (ANS) activity is associated with poor cardiovascular outcome. However, clinically validated biomarkers to assess parasympathetic function are not yet available. We sought to evaluate parasympathetic dysfunction by measuring serum cholinesterase activity and to determine its relationship to high sensitive cardiac troponin T (hs-cTnT) as well as traditional non-invasive parameters of ANS function during exercise in apparently healthy individuals. METHODS: We enrolled 1526 individuals (mean age 49â±â11âyr., 75% men) from the Tel Aviv Medical Center Inflammation Survey (TAMCIS). We used the acetylcholine (ACh) analog acetylthiocholine (ATCh) as a substrate that is hydrolyzed by both ACh degrading enzymes and reflects the total serum capacity for acetylcholine hydrolysis, referred to as cholinergic status (CS). All subjects performed a cardiac stress test reviewed on the spot by a cardiologist and multiple physiological and metabolic parameters including hs-cTnT were measured. RESULTS: CS values at rest predicted multiple exercise-hemodynamic changes. Heart rate recovery after exercise was inversely correlated to CS values (pââ5âng/L) presented with elevated CS levels compared to women with undetectable levels; 1423â±â272.5 vs 1347â±â297.9 (pâ=â0.02). An opposite trend was observed in men. Metabolic dysfunction parameters were also associated with CS elevation in both men and women. CONCLUSIONS: Parasympathetic dysfunction assessed by total serum cholinesterase activity predicts hemodynamic changes during exercise. CS is also associated with hs-cTnT detection in women and inversely so in men. Future studies to assess the potential clinical use of this new sex-specific biomarker in cardiovascular disease risk stratification are warranted
Pathological tau disrupts ongoing network activity
SummaryPathological tau leads to dementia and neurodegeneration in tauopathies, including Alzheimerâs disease. It has been shown to disrupt cellular and synaptic functions, yet its effects on the function of the intact neocortical network remain unknown. Using in vivo intracellular and extracellular recordings, we measured ongoing activity of neocortical pyramidal cells during various arousal states in the rTg4510 mouse model of tauopathy, prior to significant cell death, when only a fraction of the neurons show pathological tau. In transgenic mice, membrane potential oscillations are slower during slow-wave sleep and under anesthesia. Intracellular recordings revealed that these changes are due to longer Down states and state transitions of membrane potentials. Firing rates of transgenic neurons are reduced, and firing patterns within Up states are altered, with longer latencies and inter-spike intervals. By changing the activity patterns of a subpopulation of affected neurons, pathological tau reduces the activity of the neocortical network
Multisensory visualâtactile object related network in humans: insights gained using a novel crossmodal adaptation approach
Neuroimaging techniques have provided ample evidence for multisensory integration in humans. However, it is not clear whether this integration occurs at the neuronal level or whether it reflects areal convergence without such integration. To examine this issue as regards visuo-tactile object integration we used the repetition suppression effect, also known as the fMRI-based adaptation paradigm (fMR-A). Under some assumptions, fMR-A can tag specific neuronal populations within an area and investigate their characteristics. This technique has been used extensively in unisensory studies. Here we applied it for the first time to study multisensory integration and identified a network of occipital (LOtv and calcarine sulcus), parietal (aIPS), and prefrontal (precentral sulcus and the insula) areas all showing a clear crossmodal repetition suppression effect. These results provide a crucial first insight into the neuronal basis of visuo-haptic integration of objects in humans and highlight the power of using fMR-A to study multisensory integration using non-invasinve neuroimaging techniques
Addressing climate change with behavioral science:A global intervention tournament in 63 countries
Effectively reducing climate change requires marked, global behavior change. However, it is unclear which strategies are most likely to motivate people to change their climate beliefs and behaviors. Here, we tested 11 expert-crowdsourced interventions on four climate mitigation outcomes: beliefs, policy support, information sharing intention, and an effortful tree-planting behavioral task. Across 59,440 participants from 63 countries, the interventions' effectiveness was small, largely limited to nonclimate skeptics, and differed across outcomes: Beliefs were strengthened mostly by decreasing psychological distance (by 2.3%), policy support by writing a letter to a future-generation member (2.6%), information sharing by negative emotion induction (12.1%), and no intervention increased the more effortful behavior-several interventions even reduced tree planting. Last, the effects of each intervention differed depending on people's initial climate beliefs. These findings suggest that the impact of behavioral climate interventions varies across audiences and target behaviors.</p
Addressing climate change with behavioral science: A global intervention tournament in 63 countries
Effectively reducing climate change requires marked, global behavior change. However, it is unclear which strategies are most likely to motivate people to change their climate beliefs and behaviors. Here, we tested 11 expert-crowdsourced interventions on four climate mitigation outcomes: beliefs, policy support, information sharing intention, and an effortful tree-planting behavioral task. Across 59,440 participants from 63 countries, the interventions' effectiveness was small, largely limited to nonclimate skeptics, and differed across outcomes: Beliefs were strengthened mostly by decreasing psychological distance (by 2.3%), policy support by writing a letter to a future-generation member (2.6%), information sharing by negative emotion induction (12.1%), and no intervention increased the more effortful behavior-several interventions even reduced tree planting. Last, the effects of each intervention differed depending on people's initial climate beliefs. These findings suggest that the impact of behavioral climate interventions varies across audiences and target behaviors