פרסומים

Cognitive deficits, especially memory loss, are common following many types of brain insults which are associated with neuroinflammation, although the underlying mechanisms are not entirely clear. The present study aimed to characterize the long-term cognitive and behavioral impairments in a mouse model of neuroinflammation in the absence of other insults and to evaluate the therapeutic potential of D-cycloserine (DCS). DCS is a co-agonist of the NMDA receptor that ameliorates cognitive deficits in models of TBI and stroke. Using a mouse model of global neuroinflammation induced by intracisternal (i.c.) administration of endotoxin (LPS), we found long-lasting microgliosis, memory deficits, impaired LTP, and reduced levels of the obligatory NR1 subunit of the NMDA receptor. A single administration of DCS, 1 day after i.c. LPS reduced microgliosis, reversed the cognitive deficits and restored LTP and NR1 levels. These results demonstrate that neuroinflammation alone, in the absence of trauma or ischemia, can cause persistent (>6 months) memory deficits linked to deranged NNMDA receptor function and suggest a possible role for NMDA co-agonists in reducing the cognitive sequelae of neuroinflammation.

Sensory loss induces cross-modal plasticity, often resulting in altered performance in remaining sensory modalities. Whereas much is known about the macroscopic mechanisms underlying cross-modal plasticity, only scant information exists about its cellular and molecular underpinnings. We found that Caenorhabditis elegans nematodes deprived of a sense of body touch exhibit various changes in behavior, associated with other unimpaired senses. We focused on one such behavioral alteration, enhanced odor sensation, and sought to reveal the neuronal and molecular mechanisms that translate mechanosensory loss into improved olfactory acuity. To this end, we analyzed in mechanosensory mutants food-dependent locomotion patterns that are associated with olfactory responses and found changes that are consistent with enhanced olfaction. The altered locomotion could be reversed in adults by optogenetic stimulation of the touch receptor (mechanosensory) neurons. Furthermore, we revealed that the enhanced odor response is related to a strengthening of inhibitory AWC→AIY synaptic transmission in the olfactory circuit. Consistently, inserting in this circuit an engineered electrical synapse that diminishes AWC inhibition of AIY counteracted the locomotion changes in touch-deficient mutants. We found that this cross-modal signaling between the mechanosensory and olfactory circuits is mediated by neuropeptides, one of which we identified as FLP-20. Our results indicate that under normal function, ongoing touch receptor neuron activation evokes FLP-20 release, suppressing synaptic communication and thus dampening odor sensation. In contrast, in the absence of mechanosensory input, FLP-20 signaling is reduced, synaptic suppression is released, and this enables enhanced olfactory acuity; these changes are long lasting and do not represent ongoing modulation, as revealed by optogenetic experiments. Our work adds to a growing literature on the roles of neuropeptides in cross-modal signaling, by showing how activity-dependent neuropeptide signaling leads to specific cross-modal plastic changes in neural circuit connectivity, enhancing sensory performance.

 

PubMed DOI

 

Sensory loss induces cross-modal plasticity, often resulting in altered performance in remaining sensory modalities. Whereas much is known about the macroscopic mechanisms underlying cross-modal plasticity, only scant information exists about its cellular and molecular underpinnings. We found that Caenorhabditis elegans nematodes deprived of a sense of body touch exhibit various changes in behavior, associated with other unimpaired senses. We focused on one such behavioral alteration, enhanced odor sensation, and sought to reveal the neuronal and molecular mechanisms that translate mechanosensory loss into improved olfactory acuity. To this end, we analyzed in mechanosensory mutants food-dependent locomotion patterns that are associated with olfactory responses and found changes that are consistent with enhanced olfaction. The altered locomotion could be reversed in adults by optogenetic stimulation of the touch receptor (mechanosensory) neurons. Furthermore, we revealed that the enhanced odor response is related to a strengthening of inhibitory AWC→AIY synaptic transmission in the olfactory circuit. Consistently, inserting in this circuit an engineered electrical synapse that diminishes AWC inhibition of AIY counteracted the locomotion changes in touch-deficient mutants. We found that this cross-modal signaling between the mechanosensory and olfactory circuits is mediated by neuropeptides, one of which we identified as FLP-20. Our results indicate that under normal function, ongoing touch receptor neuron activation evokes FLP-20 release, suppressing synaptic communication and thus dampening odor sensation. In contrast, in the absence of mechanosensory input, FLP-20 signaling is reduced, synaptic suppression is released, and this enables enhanced olfactory acuity; these changes are long lasting and do not represent ongoing modulation, as revealed by optogenetic experiments. Our work adds to a growing literature on the roles of neuropeptides in cross-modal signaling, by showing how activity-dependent neuropeptide signaling leads to specific cross-modal plastic changes in neural circuit connectivity, enhancing sensory performance.

Passion fruit is a commercially important crop. The neuroprotective activity of fruit extracts from two hybrid lines of antioxidant ester thiol-rich Passiflora edulis Sims, the commercial “Passion Dream” and novel cultivar 428 (“Dena”) line were studied. Crude extracts from line 428 displayed the strongest dose-dependent neuroprotective activity, preventing glutamate induced cell-death, mitochondrial depolarization and glutathione depletion, when added to the medium of cultured HT4 neurons (p < 0.05). Supplementing diet of mice with the 428 fruit-extract improved survival of dopaminergic neurons by 60% in mice injected with the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MTPT) compared to control-fed MPTP-injected mice (p < 0.05). The neuroprotection conferred by passion fruit extracts in vivo and in vitro shows promise for further research into their bioactive potential for medical exploitation.

Passion fruit is a commercially important crop. The neuroprotective activity of fruit extracts from two hybrid lines of antioxidant ester thiol-rich Passiflora edulis Sims, the commercial “Passion Dream” and novel cultivar 428 (“Dena”) line were studied. Crude extracts from line 428 displayed the strongest dose-dependent neuroprotective activity, preventing glutamate induced cell-death, mitochondrial depolarization and glutathione depletion, when added to the medium of cultured HT4 neurons (p < 0.05). Supplementing diet of mice with the 428 fruit-extract improved survival of dopaminergic neurons by 60% in mice injected with the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MTPT) compared to control-fed MPTP-injected mice (p < 0.05). The neuroprotection conferred by passion fruit extracts in vivo and in vitro shows promise for further research into their bioactive potential for medical exploitation.

Quantitative Trait Loci (QTL) mapping is a powerful technique for dissecting the genetic basis of traits and species differences. Established tomato mapping populations between domesticated tomato (Solanum lycopersicum) and its more distant interfertile relatives typically follow a near isogenic line (NIL) design, such as the S. pennellii Introgression Line (IL) population, with a single wild introgression per line in an otherwise domesticated genetic background. Here, we report on a new advanced backcross QTL mapping resource for tomato, derived from a cross between the M82 tomato cultivar and S. pennellii. This so-called Backcrossed Inbred Line (BIL) population is comprised of a mix of BC2 and BC3 lines, with domesticated tomato as the recurrent parent. The BIL population is complementary to the existing S. pennellii IL population, with which it shares parents. Using the BILs, we mapped traits for leaf complexity, leaflet shape, and flowering time. We demonstrate the utility of the BILs for fine-mapping QTL, particularly QTL initially mapped in the ILs, by fine-mapping several QTL to single or few candidate genes. Moreover, we confirm the value of a backcrossed population with multiple introgressions per line, such as the BILs, for epistatic QTL mapping. Our work was further enabled by the development of our own statistical inference and visualization tools, namely a heterogeneous hidden Markov model for genotyping the lines, and by using state-of-the-art sparse regression techniques for QTL mapping. © 2016 Fulop et al.

ABSTRACT Nowadays, a growing number of researchers are investigating subjective attitudes of people toward their environment with ever-increasing spatial and temporal resolutions. It seems that researchers' interest in daily experiences is not merely a passing research fad, but rather that individuals in current societies find more interest in their own momentary experiences. They talk about their affective states, they spend considerable portions of their income on intangible experiences, and they instantly share personal ‘moments' through various online social media platforms. These trends are even more apparent in the tourism and leisure industries which aim to generate positive experiences among individuals. This research note points out new directions in the exploration of experiences during tourism and leisure activities. It discusses a new relevant concept, subjective momentary experiences on one hand and presents novel methodological opportunities on the other. In order to portray these new trends,...

ABSTRACT Nowadays, a growing number of researchers are investigating subjective attitudes of people toward their environment with ever-increasing spatial and temporal resolutions. It seems that researchers' interest in daily experiences is not merely a passing research fad, but rather that individuals in current societies find more interest in their own momentary experiences. They talk about their affective states, they spend considerable portions of their income on intangible experiences, and they instantly share personal ‘moments' through various online social media platforms. These trends are even more apparent in the tourism and leisure industries which aim to generate positive experiences among individuals. This research note points out new directions in the exploration of experiences during tourism and leisure activities. It discusses a new relevant concept, subjective momentary experiences on one hand and presents novel methodological opportunities on the other. In order to portray these new trends,...

The article focuses on a study which reveals the role of popular culture by shaping the East Asian region by creating transnational markets for cultural commodities and disseminating communalities of lifestyles and concepts. It informs that East Asia experiences cultural renaissance, economic growth and urban consumerism. It also informs about the issues related to the impact of trade, finance, industry and technology on creating an integrated region in East Asia.

The Dead Sea region has faced substantial environmental challenges in recent decades, including water resource scarcity, \~ 1 m annual decreases in the water level, sinkhole development, ascending-brine freshwater pollution, and seismic disturbance risks. Natural processes are significantly affected by human interference as well as by climate change and tectonic developments over the long term. To get a deep understanding of processes and their interactions, innovative scientific approaches that integrate disciplinary research and education are required. The research project DESERVE (Helmholtz Virtual Institute Dead Sea Research Venue) addresses these challenges in an interdisciplinary approach that includes geophysics, hydrology, and meteorology. The project is implemented by a consortium of scientific institutions in neighboring countries of the Dead Sea (Israel, Jordan, Palestine Territories) and participating German Helmholtz Centres (KIT, GFZ, UFZ). A new monitoring network of meteorological, hydrological, and seismic/geodynamic stations has been established, and extensive field research and numerical simulations have been undertaken. For the first time, innovative measurement and modeling techniques have been applied to the extreme conditions of the Dead Sea and its surroundings. The preliminary results show the potential of these methods. First time ever performed eddy covariance measurements give insight into the governing factors of Dead Sea evaporation. High-resolution bathymetric investigations reveal a strong correlation between submarine springs and neo-tectonic patterns. Based on detailed studies of stratigraphy and borehole information, the extension of the subsurface drainage basin of the Dead Sea is now reliably estimated. Originality has been achieved in monitoring flash floods in an arid basin at its outlet and simultaneously in tributaries, supplemented by spatio-temporal rainfall data. Low-altitude, high resolution photogrammetry, allied to satellite image analysis and to geophysical surveys (e.g. shear-wave reflections) has enabled a more detailed characterization of sinkhole morphology and temporal development and the possible subsurface controls thereon. All the above listed efforts and scientific results take place with the interdisciplinary education of young scientists. They are invited to attend joint thematic workshops and winter schools as well as to participate in field experiments

Background: Compartment boundaries are an essential developmental mechanism throughout evolution, designated to act as organizing centers and to regulate and localize differently fated cells. The hindbrain serves as a fascinating example for this phenomenon as its early development is devoted to the formation of repetitive rhombomeres and their well-defined boundaries in all vertebrates. Yet, the actual role of hindbrain boundaries remains unresolved, especially in amniotes. Results: Here, we report that hindbrain boundaries in the chick embryo consist of a subset of cells expressing the key neural stem cell (NSC) gene Sox2. These cells co-express other neural progenitor markers such as Transitin (the avian Nestin), GFAP, Pax6 and chondroitin sulfate proteoglycan. The majority of the Sox2+ cells that reside within the boundary core are slow-dividing, whereas nearer to and within rhombomeres Sox2+ cells are largely proliferating. In vivo analyses and cell tracing experiments revealed the contribution of boundary Sox2+ cells to neurons in a ventricular-to-mantle manner within the boundaries, as well as their lateral contribution to proliferating Sox2+ cells in rhombomeres. The generation of boundary-derived neurospheres from hindbrain cultures confirmed the typical NSC behavior of boundary cells as a multipotent and self-renewing Sox2+ cell population. Inhibition of Sox2 in boundaries led to enhanced and aberrant neural differentiation together with inhibition in cell-proliferation, whereas Sox2 mis-expression attenuated neurogenesis, confirming its significant function in hindbrain neuronal organization. Conclusions: Data obtained in this study deciphers a novel role of hindbrain boundaries as repetitive pools of neural stem/progenitor cells, which provide proliferating progenitors and differentiating neurons in a Sox2-dependent regulation.

A hallmark of insect societies is a division of labor among workers specializing in different tasks. In bumblebees the division of labor is related to body size; relatively small workers are more likely to stay inside the nest and tend (’’nurse’’) brood, whereas their larger sisters are more likely to forage. Despite their ecological and economic importance, very little is known about the endocrine regulation of division of labor in bumblebees. We studied the influence of juvenile hormone OH) on task performance in the bumblebee Bombus terrestris. We first used a radioimmunoassay to measure circulating JH titers in workers specializing in nursing and foraging activities. Next, we developed new protocols for manipulating JH titers by combining a size-adjusted topical treatment with the allatotoxin Precocene-I and replacement therapy with JH-III. Finally, we used this protocol to test the influence of JH on task performance. JH levels were either similar for nurses and foragers (three colonies), or higher in nurses (two colonies). Nurses had better developed ovaries and JH levels were typically positively correlated with ovarian state. Manipulation of JH titers influenced ovarian development and wax secretion, consistent with earlier allatectomy studies. These manipulations however, did not affect nursing or foraging activity, or the likelihood to specialize in nursing or foraging activity. These findings contrast with honeybees in which JH influences age -related division of labor but not adult female fertility. Thus, the evolution of complex societies in bees was associated with modifications in the way JH influences social behavior. (C) 2016 Elsevier Inc. All rights reserved.